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Nate Begeman4ebd8052005-09-01 23:24:04 +00001//===-- DAGCombiner.cpp - Implement a DAG node combiner -------------------===//
Nate Begeman1d4d4142005-09-01 00:19:25 +00002//
3// The LLVM Compiler Infrastructure
4//
Chris Lattner4ee451d2007-12-29 20:36:04 +00005// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
Nate Begeman1d4d4142005-09-01 00:19:25 +00007//
8//===----------------------------------------------------------------------===//
9//
10// This pass combines dag nodes to form fewer, simpler DAG nodes. It can be run
11// both before and after the DAG is legalized.
Scott Michelfdc40a02009-02-17 22:15:04 +000012//
Dan Gohman41287002009-04-25 17:09:45 +000013// This pass is not a substitute for the LLVM IR instcombine pass. This pass is
14// primarily intended to handle simplification opportunities that are implicit
15// in the LLVM IR and exposed by the various codegen lowering phases.
16//
Nate Begeman1d4d4142005-09-01 00:19:25 +000017//===----------------------------------------------------------------------===//
18
19#define DEBUG_TYPE "dagcombine"
Nate Begeman1d4d4142005-09-01 00:19:25 +000020#include "llvm/CodeGen/SelectionDAG.h"
Chris Lattnerc76d4412007-05-16 06:37:59 +000021#include "llvm/ADT/SmallPtrSet.h"
22#include "llvm/ADT/Statistic.h"
Chandler Carruthd04a8d42012-12-03 16:50:05 +000023#include "llvm/Analysis/AliasAnalysis.h"
24#include "llvm/CodeGen/MachineFrameInfo.h"
25#include "llvm/CodeGen/MachineFunction.h"
26#include "llvm/DataLayout.h"
27#include "llvm/DerivedTypes.h"
28#include "llvm/LLVMContext.h"
Jim Laskeyd1aed7a2006-09-21 16:28:59 +000029#include "llvm/Support/CommandLine.h"
Chris Lattnerc76d4412007-05-16 06:37:59 +000030#include "llvm/Support/Debug.h"
Torok Edwin7d696d82009-07-11 13:10:19 +000031#include "llvm/Support/ErrorHandling.h"
Chris Lattnerc76d4412007-05-16 06:37:59 +000032#include "llvm/Support/MathExtras.h"
Chris Lattnerbbbfa992009-08-23 06:35:02 +000033#include "llvm/Support/raw_ostream.h"
Chandler Carruthd04a8d42012-12-03 16:50:05 +000034#include "llvm/Target/TargetLowering.h"
35#include "llvm/Target/TargetMachine.h"
36#include "llvm/Target/TargetOptions.h"
Chris Lattnera500fc62005-09-09 23:53:39 +000037#include <algorithm>
Nate Begeman1d4d4142005-09-01 00:19:25 +000038using namespace llvm;
39
Chris Lattnercd3245a2006-12-19 22:41:21 +000040STATISTIC(NodesCombined , "Number of dag nodes combined");
41STATISTIC(PreIndexedNodes , "Number of pre-indexed nodes created");
42STATISTIC(PostIndexedNodes, "Number of post-indexed nodes created");
Evan Cheng8b944d32009-05-28 00:35:15 +000043STATISTIC(OpsNarrowed , "Number of load/op/store narrowed");
Evan Cheng31959b12011-02-02 01:06:55 +000044STATISTIC(LdStFP2Int , "Number of fp load/store pairs transformed to int");
Chris Lattnercd3245a2006-12-19 22:41:21 +000045
Nate Begeman1d4d4142005-09-01 00:19:25 +000046namespace {
Jim Laskey71382342006-10-07 23:37:56 +000047 static cl::opt<bool>
Owen Anderson0dcc8142010-09-19 21:01:26 +000048 CombinerAA("combiner-alias-analysis", cl::Hidden,
Jim Laskey26f7fa72006-10-17 19:33:52 +000049 cl::desc("Turn on alias analysis during testing"));
Jim Laskey3ad175b2006-10-12 15:22:24 +000050
Jim Laskey07a27092006-10-18 19:08:31 +000051 static cl::opt<bool>
52 CombinerGlobalAA("combiner-global-alias-analysis", cl::Hidden,
53 cl::desc("Include global information in alias analysis"));
54
Jim Laskeybc588b82006-10-05 15:07:25 +000055//------------------------------ DAGCombiner ---------------------------------//
56
Nick Lewycky6726b6d2009-10-25 06:33:48 +000057 class DAGCombiner {
Nate Begeman1d4d4142005-09-01 00:19:25 +000058 SelectionDAG &DAG;
Dan Gohman79ce2762009-01-15 19:20:50 +000059 const TargetLowering &TLI;
Duncan Sands25cf2272008-11-24 14:53:14 +000060 CombineLevel Level;
Bill Wendling98a366d2009-04-29 23:29:43 +000061 CodeGenOpt::Level OptLevel;
Duncan Sands25cf2272008-11-24 14:53:14 +000062 bool LegalOperations;
63 bool LegalTypes;
Nate Begeman1d4d4142005-09-01 00:19:25 +000064
65 // Worklist of all of the nodes that need to be simplified.
James Molloy6660c052012-02-16 09:17:04 +000066 //
67 // This has the semantics that when adding to the worklist,
68 // the item added must be next to be processed. It should
69 // also only appear once. The naive approach to this takes
70 // linear time.
71 //
72 // To reduce the insert/remove time to logarithmic, we use
73 // a set and a vector to maintain our worklist.
74 //
75 // The set contains the items on the worklist, but does not
76 // maintain the order they should be visited.
77 //
78 // The vector maintains the order nodes should be visited, but may
79 // contain duplicate or removed nodes. When choosing a node to
80 // visit, we pop off the order stack until we find an item that is
81 // also in the contents set. All operations are O(log N).
82 SmallPtrSet<SDNode*, 64> WorkListContents;
Benjamin Kramerd5f76902012-03-10 00:23:58 +000083 SmallVector<SDNode*, 64> WorkListOrder;
Nate Begeman1d4d4142005-09-01 00:19:25 +000084
Jim Laskeyc7c3f112006-10-16 20:52:31 +000085 // AA - Used for DAG load/store alias analysis.
86 AliasAnalysis &AA;
87
Nate Begeman1d4d4142005-09-01 00:19:25 +000088 /// AddUsersToWorkList - When an instruction is simplified, add all users of
89 /// the instruction to the work lists because they might get more simplified
90 /// now.
91 ///
92 void AddUsersToWorkList(SDNode *N) {
93 for (SDNode::use_iterator UI = N->use_begin(), UE = N->use_end();
Nate Begeman4ebd8052005-09-01 23:24:04 +000094 UI != UE; ++UI)
Dan Gohman89684502008-07-27 20:43:25 +000095 AddToWorkList(*UI);
Nate Begeman1d4d4142005-09-01 00:19:25 +000096 }
97
Dan Gohman389079b2007-10-08 17:57:15 +000098 /// visit - call the node-specific routine that knows how to fold each
99 /// particular type of node.
Dan Gohman475871a2008-07-27 21:46:04 +0000100 SDValue visit(SDNode *N);
Dan Gohman389079b2007-10-08 17:57:15 +0000101
Chris Lattner24664722006-03-01 04:53:38 +0000102 public:
James Molloy6afa3f72012-02-16 09:48:07 +0000103 /// AddToWorkList - Add to the work list making sure its instance is at the
James Molloy6660c052012-02-16 09:17:04 +0000104 /// back (next to be processed.)
Chris Lattner5750df92006-03-01 04:03:14 +0000105 void AddToWorkList(SDNode *N) {
James Molloy6660c052012-02-16 09:17:04 +0000106 WorkListContents.insert(N);
107 WorkListOrder.push_back(N);
Chris Lattner5750df92006-03-01 04:03:14 +0000108 }
Jim Laskey6ff23e52006-10-04 16:53:27 +0000109
Chris Lattnerf8dc0612008-02-03 06:49:24 +0000110 /// removeFromWorkList - remove all instances of N from the worklist.
111 ///
112 void removeFromWorkList(SDNode *N) {
James Molloy6660c052012-02-16 09:17:04 +0000113 WorkListContents.erase(N);
Chris Lattner01a22022005-10-10 22:04:48 +0000114 }
Scott Michelfdc40a02009-02-17 22:15:04 +0000115
Dan Gohman475871a2008-07-27 21:46:04 +0000116 SDValue CombineTo(SDNode *N, const SDValue *To, unsigned NumTo,
Evan Cheng0b0cd912009-03-28 05:57:29 +0000117 bool AddTo = true);
Scott Michelfdc40a02009-02-17 22:15:04 +0000118
Dan Gohman475871a2008-07-27 21:46:04 +0000119 SDValue CombineTo(SDNode *N, SDValue Res, bool AddTo = true) {
Jim Laskey274062c2006-10-13 23:32:28 +0000120 return CombineTo(N, &Res, 1, AddTo);
Chris Lattner24664722006-03-01 04:53:38 +0000121 }
Scott Michelfdc40a02009-02-17 22:15:04 +0000122
Dan Gohman475871a2008-07-27 21:46:04 +0000123 SDValue CombineTo(SDNode *N, SDValue Res0, SDValue Res1,
Evan Cheng0b0cd912009-03-28 05:57:29 +0000124 bool AddTo = true) {
Dan Gohman475871a2008-07-27 21:46:04 +0000125 SDValue To[] = { Res0, Res1 };
Jim Laskey274062c2006-10-13 23:32:28 +0000126 return CombineTo(N, To, 2, AddTo);
Chris Lattner24664722006-03-01 04:53:38 +0000127 }
Dan Gohmane5af2d32009-01-29 01:59:02 +0000128
129 void CommitTargetLoweringOpt(const TargetLowering::TargetLoweringOpt &TLO);
Scott Michelfdc40a02009-02-17 22:15:04 +0000130
131 private:
132
Chris Lattner012f2412006-02-17 21:58:01 +0000133 /// SimplifyDemandedBits - Check the specified integer node value to see if
Chris Lattnerb2742f42006-03-01 19:55:35 +0000134 /// it can be simplified or if things it uses can be simplified by bit
Chris Lattner012f2412006-02-17 21:58:01 +0000135 /// propagation. If so, return true.
Dan Gohman475871a2008-07-27 21:46:04 +0000136 bool SimplifyDemandedBits(SDValue Op) {
Dan Gohman87862e72009-12-11 21:31:27 +0000137 unsigned BitWidth = Op.getValueType().getScalarType().getSizeInBits();
138 APInt Demanded = APInt::getAllOnesValue(BitWidth);
Dan Gohman7b8d4a92008-02-27 00:25:32 +0000139 return SimplifyDemandedBits(Op, Demanded);
140 }
141
Dan Gohman475871a2008-07-27 21:46:04 +0000142 bool SimplifyDemandedBits(SDValue Op, const APInt &Demanded);
Chris Lattner87514ca2005-10-10 22:31:19 +0000143
Chris Lattner448f2192006-11-11 00:39:41 +0000144 bool CombineToPreIndexedLoadStore(SDNode *N);
145 bool CombineToPostIndexedLoadStore(SDNode *N);
Scott Michelfdc40a02009-02-17 22:15:04 +0000146
Evan Cheng95c57ea2010-04-24 04:43:44 +0000147 void ReplaceLoadWithPromotedLoad(SDNode *Load, SDNode *ExtLoad);
148 SDValue PromoteOperand(SDValue Op, EVT PVT, bool &Replace);
149 SDValue SExtPromoteOperand(SDValue Op, EVT PVT);
150 SDValue ZExtPromoteOperand(SDValue Op, EVT PVT);
Evan Cheng64b7bf72010-04-16 06:14:10 +0000151 SDValue PromoteIntBinOp(SDValue Op);
Evan Cheng07c4e102010-04-22 20:19:46 +0000152 SDValue PromoteIntShiftOp(SDValue Op);
Evan Cheng4c26e932010-04-19 19:29:22 +0000153 SDValue PromoteExtend(SDValue Op);
154 bool PromoteLoad(SDValue Op);
Scott Michelfdc40a02009-02-17 22:15:04 +0000155
Nick Lewyckyc06b5bf2011-06-16 01:15:49 +0000156 void ExtendSetCCUses(SmallVector<SDNode*, 4> SetCCs,
157 SDValue Trunc, SDValue ExtLoad, DebugLoc DL,
158 ISD::NodeType ExtType);
159
Dan Gohman389079b2007-10-08 17:57:15 +0000160 /// combine - call the node-specific routine that knows how to fold each
161 /// particular type of node. If that doesn't do anything, try the
162 /// target-specific DAG combines.
Dan Gohman475871a2008-07-27 21:46:04 +0000163 SDValue combine(SDNode *N);
Nate Begeman1d4d4142005-09-01 00:19:25 +0000164
165 // Visitation implementation - Implement dag node combining for different
166 // node types. The semantics are as follows:
167 // Return Value:
Evan Cheng17a568b2008-08-29 22:21:44 +0000168 // SDValue.getNode() == 0 - No change was made
169 // SDValue.getNode() == N - N was replaced, is dead and has been handled.
170 // otherwise - N should be replaced by the returned Operand.
Nate Begeman1d4d4142005-09-01 00:19:25 +0000171 //
Dan Gohman475871a2008-07-27 21:46:04 +0000172 SDValue visitTokenFactor(SDNode *N);
173 SDValue visitMERGE_VALUES(SDNode *N);
174 SDValue visitADD(SDNode *N);
175 SDValue visitSUB(SDNode *N);
176 SDValue visitADDC(SDNode *N);
Craig Toppercc274522012-01-07 09:06:39 +0000177 SDValue visitSUBC(SDNode *N);
Dan Gohman475871a2008-07-27 21:46:04 +0000178 SDValue visitADDE(SDNode *N);
Craig Toppercc274522012-01-07 09:06:39 +0000179 SDValue visitSUBE(SDNode *N);
Dan Gohman475871a2008-07-27 21:46:04 +0000180 SDValue visitMUL(SDNode *N);
181 SDValue visitSDIV(SDNode *N);
182 SDValue visitUDIV(SDNode *N);
183 SDValue visitSREM(SDNode *N);
184 SDValue visitUREM(SDNode *N);
185 SDValue visitMULHU(SDNode *N);
186 SDValue visitMULHS(SDNode *N);
187 SDValue visitSMUL_LOHI(SDNode *N);
188 SDValue visitUMUL_LOHI(SDNode *N);
Benjamin Kramerf55d26e2011-05-21 18:31:55 +0000189 SDValue visitSMULO(SDNode *N);
190 SDValue visitUMULO(SDNode *N);
Dan Gohman475871a2008-07-27 21:46:04 +0000191 SDValue visitSDIVREM(SDNode *N);
192 SDValue visitUDIVREM(SDNode *N);
193 SDValue visitAND(SDNode *N);
194 SDValue visitOR(SDNode *N);
195 SDValue visitXOR(SDNode *N);
196 SDValue SimplifyVBinOp(SDNode *N);
Craig Topperdd201ff2012-09-11 01:45:21 +0000197 SDValue SimplifyVUnaryOp(SDNode *N);
Dan Gohman475871a2008-07-27 21:46:04 +0000198 SDValue visitSHL(SDNode *N);
199 SDValue visitSRA(SDNode *N);
200 SDValue visitSRL(SDNode *N);
201 SDValue visitCTLZ(SDNode *N);
Chandler Carruth63974b22011-12-13 01:56:10 +0000202 SDValue visitCTLZ_ZERO_UNDEF(SDNode *N);
Dan Gohman475871a2008-07-27 21:46:04 +0000203 SDValue visitCTTZ(SDNode *N);
Chandler Carruth63974b22011-12-13 01:56:10 +0000204 SDValue visitCTTZ_ZERO_UNDEF(SDNode *N);
Dan Gohman475871a2008-07-27 21:46:04 +0000205 SDValue visitCTPOP(SDNode *N);
206 SDValue visitSELECT(SDNode *N);
207 SDValue visitSELECT_CC(SDNode *N);
208 SDValue visitSETCC(SDNode *N);
209 SDValue visitSIGN_EXTEND(SDNode *N);
210 SDValue visitZERO_EXTEND(SDNode *N);
211 SDValue visitANY_EXTEND(SDNode *N);
212 SDValue visitSIGN_EXTEND_INREG(SDNode *N);
213 SDValue visitTRUNCATE(SDNode *N);
Wesley Peckbf17cfa2010-11-23 03:31:01 +0000214 SDValue visitBITCAST(SDNode *N);
Dan Gohman475871a2008-07-27 21:46:04 +0000215 SDValue visitBUILD_PAIR(SDNode *N);
216 SDValue visitFADD(SDNode *N);
217 SDValue visitFSUB(SDNode *N);
218 SDValue visitFMUL(SDNode *N);
Owen Anderson062c0a52012-05-02 22:17:40 +0000219 SDValue visitFMA(SDNode *N);
Dan Gohman475871a2008-07-27 21:46:04 +0000220 SDValue visitFDIV(SDNode *N);
221 SDValue visitFREM(SDNode *N);
222 SDValue visitFCOPYSIGN(SDNode *N);
223 SDValue visitSINT_TO_FP(SDNode *N);
224 SDValue visitUINT_TO_FP(SDNode *N);
225 SDValue visitFP_TO_SINT(SDNode *N);
226 SDValue visitFP_TO_UINT(SDNode *N);
227 SDValue visitFP_ROUND(SDNode *N);
228 SDValue visitFP_ROUND_INREG(SDNode *N);
229 SDValue visitFP_EXTEND(SDNode *N);
230 SDValue visitFNEG(SDNode *N);
231 SDValue visitFABS(SDNode *N);
Owen Anderson7c626d32012-08-13 23:32:49 +0000232 SDValue visitFCEIL(SDNode *N);
233 SDValue visitFTRUNC(SDNode *N);
234 SDValue visitFFLOOR(SDNode *N);
Dan Gohman475871a2008-07-27 21:46:04 +0000235 SDValue visitBRCOND(SDNode *N);
236 SDValue visitBR_CC(SDNode *N);
237 SDValue visitLOAD(SDNode *N);
238 SDValue visitSTORE(SDNode *N);
239 SDValue visitINSERT_VECTOR_ELT(SDNode *N);
240 SDValue visitEXTRACT_VECTOR_ELT(SDNode *N);
241 SDValue visitBUILD_VECTOR(SDNode *N);
242 SDValue visitCONCAT_VECTORS(SDNode *N);
Bruno Cardoso Lopese97190f2011-09-20 23:19:33 +0000243 SDValue visitEXTRACT_SUBVECTOR(SDNode *N);
Dan Gohman475871a2008-07-27 21:46:04 +0000244 SDValue visitVECTOR_SHUFFLE(SDNode *N);
Jim Grosbach9a526492010-06-23 16:07:42 +0000245 SDValue visitMEMBARRIER(SDNode *N);
Chris Lattner01a22022005-10-10 22:04:48 +0000246
Dan Gohman475871a2008-07-27 21:46:04 +0000247 SDValue XformToShuffleWithZero(SDNode *N);
Bill Wendling35247c32009-01-30 00:45:56 +0000248 SDValue ReassociateOps(unsigned Opc, DebugLoc DL, SDValue LHS, SDValue RHS);
Scott Michelfdc40a02009-02-17 22:15:04 +0000249
Dan Gohman475871a2008-07-27 21:46:04 +0000250 SDValue visitShiftByConstant(SDNode *N, unsigned Amt);
Chris Lattnere70da202007-12-06 07:33:36 +0000251
Dan Gohman475871a2008-07-27 21:46:04 +0000252 bool SimplifySelectOps(SDNode *SELECT, SDValue LHS, SDValue RHS);
253 SDValue SimplifyBinOpWithSameOpcodeHands(SDNode *N);
Bill Wendling836ca7d2009-01-30 23:59:18 +0000254 SDValue SimplifySelect(DebugLoc DL, SDValue N0, SDValue N1, SDValue N2);
Scott Michelfdc40a02009-02-17 22:15:04 +0000255 SDValue SimplifySelectCC(DebugLoc DL, SDValue N0, SDValue N1, SDValue N2,
256 SDValue N3, ISD::CondCode CC,
Bill Wendling836ca7d2009-01-30 23:59:18 +0000257 bool NotExtCompare = false);
Owen Andersone50ed302009-08-10 22:56:29 +0000258 SDValue SimplifySetCC(EVT VT, SDValue N0, SDValue N1, ISD::CondCode Cond,
Dale Johannesenff97d4f2009-02-03 00:47:48 +0000259 DebugLoc DL, bool foldBooleans = true);
Scott Michelfdc40a02009-02-17 22:15:04 +0000260 SDValue SimplifyNodeWithTwoResults(SDNode *N, unsigned LoOp,
Chris Lattner5eee4272008-01-26 01:09:19 +0000261 unsigned HiOp);
Owen Andersone50ed302009-08-10 22:56:29 +0000262 SDValue CombineConsecutiveLoads(SDNode *N, EVT VT);
Wesley Peckbf17cfa2010-11-23 03:31:01 +0000263 SDValue ConstantFoldBITCASTofBUILD_VECTOR(SDNode *, EVT);
Dan Gohman475871a2008-07-27 21:46:04 +0000264 SDValue BuildSDIV(SDNode *N);
265 SDValue BuildUDIV(SDNode *N);
Evan Cheng9568e5c2011-06-21 06:01:08 +0000266 SDValue MatchBSwapHWordLow(SDNode *N, SDValue N0, SDValue N1,
267 bool DemandHighBits = true);
268 SDValue MatchBSwapHWord(SDNode *N, SDValue N0, SDValue N1);
Bill Wendling317bd702009-01-30 21:14:50 +0000269 SDNode *MatchRotate(SDValue LHS, SDValue RHS, DebugLoc DL);
Dan Gohman475871a2008-07-27 21:46:04 +0000270 SDValue ReduceLoadWidth(SDNode *N);
Evan Cheng8b944d32009-05-28 00:35:15 +0000271 SDValue ReduceLoadOpStoreWidth(SDNode *N);
Evan Cheng31959b12011-02-02 01:06:55 +0000272 SDValue TransformFPLoadStorePair(SDNode *N);
Michael Liaofac14ab2012-10-23 23:06:52 +0000273 SDValue reduceBuildVecExtToExtBuildVec(SDNode *N);
Michael Liao1a5cc712012-10-24 04:14:18 +0000274 SDValue reduceBuildVecConvertToConvertBuildVec(SDNode *N);
Scott Michelfdc40a02009-02-17 22:15:04 +0000275
Dan Gohman475871a2008-07-27 21:46:04 +0000276 SDValue GetDemandedBits(SDValue V, const APInt &Mask);
Scott Michelfdc40a02009-02-17 22:15:04 +0000277
Jim Laskey6ff23e52006-10-04 16:53:27 +0000278 /// GatherAllAliases - Walk up chain skipping non-aliasing memory nodes,
279 /// looking for aliasing nodes and adding them to the Aliases vector.
Dan Gohman475871a2008-07-27 21:46:04 +0000280 void GatherAllAliases(SDNode *N, SDValue OriginalChain,
281 SmallVector<SDValue, 8> &Aliases);
Jim Laskey6ff23e52006-10-04 16:53:27 +0000282
Jim Laskey096c22e2006-10-18 12:29:57 +0000283 /// isAlias - Return true if there is any possibility that the two addresses
284 /// overlap.
Dan Gohman475871a2008-07-27 21:46:04 +0000285 bool isAlias(SDValue Ptr1, int64_t Size1,
Jim Laskey096c22e2006-10-18 12:29:57 +0000286 const Value *SrcValue1, int SrcValueOffset1,
Nate Begemanb6aef5c2009-09-15 00:18:30 +0000287 unsigned SrcValueAlign1,
Dan Gohmanf96e4bd2010-10-20 00:31:05 +0000288 const MDNode *TBAAInfo1,
Dan Gohman475871a2008-07-27 21:46:04 +0000289 SDValue Ptr2, int64_t Size2,
Nate Begemanb6aef5c2009-09-15 00:18:30 +0000290 const Value *SrcValue2, int SrcValueOffset2,
Dan Gohmanf96e4bd2010-10-20 00:31:05 +0000291 unsigned SrcValueAlign2,
292 const MDNode *TBAAInfo2) const;
Scott Michelfdc40a02009-02-17 22:15:04 +0000293
Nadav Rotem90e11dc2012-11-29 00:00:08 +0000294 /// isAlias - Return true if there is any possibility that the two addresses
295 /// overlap.
296 bool isAlias(LSBaseSDNode *Op0, LSBaseSDNode *Op1);
297
Jim Laskey7ca56af2006-10-11 13:47:09 +0000298 /// FindAliasInfo - Extracts the relevant alias information from the memory
299 /// node. Returns true if the operand was a load.
300 bool FindAliasInfo(SDNode *N,
Dan Gohman475871a2008-07-27 21:46:04 +0000301 SDValue &Ptr, int64_t &Size,
Nate Begemanb6aef5c2009-09-15 00:18:30 +0000302 const Value *&SrcValue, int &SrcValueOffset,
Dan Gohmanf96e4bd2010-10-20 00:31:05 +0000303 unsigned &SrcValueAlignment,
304 const MDNode *&TBAAInfo) const;
Scott Michelfdc40a02009-02-17 22:15:04 +0000305
Jim Laskey279f0532006-09-25 16:29:54 +0000306 /// FindBetterChain - Walk up chain skipping non-aliasing memory nodes,
Jim Laskey6ff23e52006-10-04 16:53:27 +0000307 /// looking for a better chain (aliasing node.)
Dan Gohman475871a2008-07-27 21:46:04 +0000308 SDValue FindBetterChain(SDNode *N, SDValue Chain);
Duncan Sands92abc622009-01-31 15:50:11 +0000309
Nadav Rotemc653de62012-10-03 16:11:15 +0000310 /// Merge consecutive store operations into a wide store.
311 /// This optimization uses wide integers or vectors when possible.
312 /// \return True if some memory operations were changed.
313 bool MergeConsecutiveStores(StoreSDNode *N);
314
Chris Lattner2392ae72010-04-15 04:48:01 +0000315 public:
Bill Wendling98a366d2009-04-29 23:29:43 +0000316 DAGCombiner(SelectionDAG &D, AliasAnalysis &A, CodeGenOpt::Level OL)
Eli Friedman50185242011-11-12 00:35:34 +0000317 : DAG(D), TLI(D.getTargetLoweringInfo()), Level(BeforeLegalizeTypes),
Chris Lattner2392ae72010-04-15 04:48:01 +0000318 OptLevel(OL), LegalOperations(false), LegalTypes(false), AA(A) {}
Scott Michelfdc40a02009-02-17 22:15:04 +0000319
Nate Begeman1d4d4142005-09-01 00:19:25 +0000320 /// Run - runs the dag combiner on all nodes in the work list
Duncan Sands25cf2272008-11-24 14:53:14 +0000321 void Run(CombineLevel AtLevel);
Wesley Peckbf17cfa2010-11-23 03:31:01 +0000322
Chris Lattner2392ae72010-04-15 04:48:01 +0000323 SelectionDAG &getDAG() const { return DAG; }
Wesley Peckbf17cfa2010-11-23 03:31:01 +0000324
Chris Lattner2392ae72010-04-15 04:48:01 +0000325 /// getShiftAmountTy - Returns a type large enough to hold any valid
326 /// shift amount - before type legalization these can be huge.
Owen Anderson95771af2011-02-25 21:41:48 +0000327 EVT getShiftAmountTy(EVT LHSTy) {
328 return LegalTypes ? TLI.getShiftAmountTy(LHSTy) : TLI.getPointerTy();
Chris Lattner2392ae72010-04-15 04:48:01 +0000329 }
Wesley Peckbf17cfa2010-11-23 03:31:01 +0000330
Chris Lattner2392ae72010-04-15 04:48:01 +0000331 /// isTypeLegal - This method returns true if we are running before type
332 /// legalization or if the specified VT is legal.
333 bool isTypeLegal(const EVT &VT) {
334 if (!LegalTypes) return true;
335 return TLI.isTypeLegal(VT);
336 }
Nate Begeman1d4d4142005-09-01 00:19:25 +0000337 };
338}
339
Chris Lattnerf8dc0612008-02-03 06:49:24 +0000340
341namespace {
342/// WorkListRemover - This class is a DAGUpdateListener that removes any deleted
343/// nodes from the worklist.
Nick Lewycky6726b6d2009-10-25 06:33:48 +0000344class WorkListRemover : public SelectionDAG::DAGUpdateListener {
Chris Lattnerf8dc0612008-02-03 06:49:24 +0000345 DAGCombiner &DC;
346public:
Jakob Stoklund Olesenbc7d4482012-04-20 22:08:46 +0000347 explicit WorkListRemover(DAGCombiner &dc)
348 : SelectionDAG::DAGUpdateListener(dc.getDAG()), DC(dc) {}
Scott Michelfdc40a02009-02-17 22:15:04 +0000349
Duncan Sandsedfcf592008-06-11 11:42:12 +0000350 virtual void NodeDeleted(SDNode *N, SDNode *E) {
Chris Lattnerf8dc0612008-02-03 06:49:24 +0000351 DC.removeFromWorkList(N);
352 }
Chris Lattnerf8dc0612008-02-03 06:49:24 +0000353};
354}
355
Chris Lattner24664722006-03-01 04:53:38 +0000356//===----------------------------------------------------------------------===//
357// TargetLowering::DAGCombinerInfo implementation
358//===----------------------------------------------------------------------===//
359
360void TargetLowering::DAGCombinerInfo::AddToWorklist(SDNode *N) {
361 ((DAGCombiner*)DC)->AddToWorkList(N);
362}
363
Cameron Zwariched3caf92011-04-02 02:40:26 +0000364void TargetLowering::DAGCombinerInfo::RemoveFromWorklist(SDNode *N) {
365 ((DAGCombiner*)DC)->removeFromWorkList(N);
366}
367
Dan Gohman475871a2008-07-27 21:46:04 +0000368SDValue TargetLowering::DAGCombinerInfo::
Evan Cheng0b0cd912009-03-28 05:57:29 +0000369CombineTo(SDNode *N, const std::vector<SDValue> &To, bool AddTo) {
370 return ((DAGCombiner*)DC)->CombineTo(N, &To[0], To.size(), AddTo);
Chris Lattner24664722006-03-01 04:53:38 +0000371}
372
Dan Gohman475871a2008-07-27 21:46:04 +0000373SDValue TargetLowering::DAGCombinerInfo::
Evan Cheng0b0cd912009-03-28 05:57:29 +0000374CombineTo(SDNode *N, SDValue Res, bool AddTo) {
375 return ((DAGCombiner*)DC)->CombineTo(N, Res, AddTo);
Chris Lattner24664722006-03-01 04:53:38 +0000376}
377
378
Dan Gohman475871a2008-07-27 21:46:04 +0000379SDValue TargetLowering::DAGCombinerInfo::
Evan Cheng0b0cd912009-03-28 05:57:29 +0000380CombineTo(SDNode *N, SDValue Res0, SDValue Res1, bool AddTo) {
381 return ((DAGCombiner*)DC)->CombineTo(N, Res0, Res1, AddTo);
Chris Lattner24664722006-03-01 04:53:38 +0000382}
383
Dan Gohmane5af2d32009-01-29 01:59:02 +0000384void TargetLowering::DAGCombinerInfo::
385CommitTargetLoweringOpt(const TargetLowering::TargetLoweringOpt &TLO) {
386 return ((DAGCombiner*)DC)->CommitTargetLoweringOpt(TLO);
387}
Chris Lattner24664722006-03-01 04:53:38 +0000388
Chris Lattner24664722006-03-01 04:53:38 +0000389//===----------------------------------------------------------------------===//
Chris Lattner29446522007-05-14 22:04:50 +0000390// Helper Functions
391//===----------------------------------------------------------------------===//
392
393/// isNegatibleForFree - Return 1 if we can compute the negated form of the
394/// specified expression for the same cost as the expression itself, or 2 if we
395/// can compute the negated form more cheaply than the expression itself.
Duncan Sands25cf2272008-11-24 14:53:14 +0000396static char isNegatibleForFree(SDValue Op, bool LegalOperations,
Owen Andersonafd3d562012-03-06 00:29:31 +0000397 const TargetLowering &TLI,
Nick Lewycky8a8d4792011-12-02 22:16:29 +0000398 const TargetOptions *Options,
Chris Lattner0254e702008-02-26 07:04:54 +0000399 unsigned Depth = 0) {
Chris Lattner29446522007-05-14 22:04:50 +0000400 // fneg is removable even if it has multiple uses.
401 if (Op.getOpcode() == ISD::FNEG) return 2;
Scott Michelfdc40a02009-02-17 22:15:04 +0000402
Chris Lattner29446522007-05-14 22:04:50 +0000403 // Don't allow anything with multiple uses.
404 if (!Op.hasOneUse()) return 0;
Scott Michelfdc40a02009-02-17 22:15:04 +0000405
Chris Lattner3adf9512007-05-25 02:19:06 +0000406 // Don't recurse exponentially.
407 if (Depth > 6) return 0;
Scott Michelfdc40a02009-02-17 22:15:04 +0000408
Chris Lattner29446522007-05-14 22:04:50 +0000409 switch (Op.getOpcode()) {
410 default: return false;
411 case ISD::ConstantFP:
Chris Lattner0254e702008-02-26 07:04:54 +0000412 // Don't invert constant FP values after legalize. The negated constant
413 // isn't necessarily legal.
Duncan Sands25cf2272008-11-24 14:53:14 +0000414 return LegalOperations ? 0 : 1;
Chris Lattner29446522007-05-14 22:04:50 +0000415 case ISD::FADD:
416 // FIXME: determine better conditions for this xform.
Nick Lewycky8a8d4792011-12-02 22:16:29 +0000417 if (!Options->UnsafeFPMath) return 0;
Scott Michelfdc40a02009-02-17 22:15:04 +0000418
Owen Andersonafd3d562012-03-06 00:29:31 +0000419 // After operation legalization, it might not be legal to create new FSUBs.
420 if (LegalOperations &&
421 !TLI.isOperationLegalOrCustom(ISD::FSUB, Op.getValueType()))
422 return 0;
423
Craig Topper956342b2012-09-09 22:58:45 +0000424 // fold (fneg (fadd A, B)) -> (fsub (fneg A), B)
Owen Andersonafd3d562012-03-06 00:29:31 +0000425 if (char V = isNegatibleForFree(Op.getOperand(0), LegalOperations, TLI,
426 Options, Depth + 1))
Chris Lattner29446522007-05-14 22:04:50 +0000427 return V;
Bill Wendlingd34470c2009-01-30 23:10:18 +0000428 // fold (fneg (fadd A, B)) -> (fsub (fneg B), A)
Owen Andersonafd3d562012-03-06 00:29:31 +0000429 return isNegatibleForFree(Op.getOperand(1), LegalOperations, TLI, Options,
Nick Lewycky8a8d4792011-12-02 22:16:29 +0000430 Depth + 1);
Chris Lattner29446522007-05-14 22:04:50 +0000431 case ISD::FSUB:
Scott Michelfdc40a02009-02-17 22:15:04 +0000432 // We can't turn -(A-B) into B-A when we honor signed zeros.
Nick Lewycky8a8d4792011-12-02 22:16:29 +0000433 if (!Options->UnsafeFPMath) return 0;
Scott Michelfdc40a02009-02-17 22:15:04 +0000434
Bill Wendlingd34470c2009-01-30 23:10:18 +0000435 // fold (fneg (fsub A, B)) -> (fsub B, A)
Chris Lattner29446522007-05-14 22:04:50 +0000436 return 1;
Scott Michelfdc40a02009-02-17 22:15:04 +0000437
Chris Lattner29446522007-05-14 22:04:50 +0000438 case ISD::FMUL:
439 case ISD::FDIV:
Nick Lewycky8a8d4792011-12-02 22:16:29 +0000440 if (Options->HonorSignDependentRoundingFPMath()) return 0;
Scott Michelfdc40a02009-02-17 22:15:04 +0000441
Bill Wendlingd34470c2009-01-30 23:10:18 +0000442 // fold (fneg (fmul X, Y)) -> (fmul (fneg X), Y) or (fmul X, (fneg Y))
Owen Andersonafd3d562012-03-06 00:29:31 +0000443 if (char V = isNegatibleForFree(Op.getOperand(0), LegalOperations, TLI,
444 Options, Depth + 1))
Chris Lattner29446522007-05-14 22:04:50 +0000445 return V;
Scott Michelfdc40a02009-02-17 22:15:04 +0000446
Owen Andersonafd3d562012-03-06 00:29:31 +0000447 return isNegatibleForFree(Op.getOperand(1), LegalOperations, TLI, Options,
Nick Lewycky8a8d4792011-12-02 22:16:29 +0000448 Depth + 1);
Scott Michelfdc40a02009-02-17 22:15:04 +0000449
Chris Lattner29446522007-05-14 22:04:50 +0000450 case ISD::FP_EXTEND:
451 case ISD::FP_ROUND:
452 case ISD::FSIN:
Owen Andersonafd3d562012-03-06 00:29:31 +0000453 return isNegatibleForFree(Op.getOperand(0), LegalOperations, TLI, Options,
Nick Lewycky8a8d4792011-12-02 22:16:29 +0000454 Depth + 1);
Chris Lattner29446522007-05-14 22:04:50 +0000455 }
456}
457
458/// GetNegatedExpression - If isNegatibleForFree returns true, this function
459/// returns the newly negated expression.
Dan Gohman475871a2008-07-27 21:46:04 +0000460static SDValue GetNegatedExpression(SDValue Op, SelectionDAG &DAG,
Duncan Sands25cf2272008-11-24 14:53:14 +0000461 bool LegalOperations, unsigned Depth = 0) {
Chris Lattner29446522007-05-14 22:04:50 +0000462 // fneg is removable even if it has multiple uses.
463 if (Op.getOpcode() == ISD::FNEG) return Op.getOperand(0);
Scott Michelfdc40a02009-02-17 22:15:04 +0000464
Chris Lattner29446522007-05-14 22:04:50 +0000465 // Don't allow anything with multiple uses.
466 assert(Op.hasOneUse() && "Unknown reuse!");
Scott Michelfdc40a02009-02-17 22:15:04 +0000467
Chris Lattner3adf9512007-05-25 02:19:06 +0000468 assert(Depth <= 6 && "GetNegatedExpression doesn't match isNegatibleForFree");
Chris Lattner29446522007-05-14 22:04:50 +0000469 switch (Op.getOpcode()) {
Torok Edwinc23197a2009-07-14 16:55:14 +0000470 default: llvm_unreachable("Unknown code");
Dale Johannesenc4dd3c32007-08-31 23:34:27 +0000471 case ISD::ConstantFP: {
472 APFloat V = cast<ConstantFPSDNode>(Op)->getValueAPF();
473 V.changeSign();
474 return DAG.getConstantFP(V, Op.getValueType());
475 }
Chris Lattner29446522007-05-14 22:04:50 +0000476 case ISD::FADD:
477 // FIXME: determine better conditions for this xform.
Nick Lewycky8a8d4792011-12-02 22:16:29 +0000478 assert(DAG.getTarget().Options.UnsafeFPMath);
Scott Michelfdc40a02009-02-17 22:15:04 +0000479
Bill Wendlingd34470c2009-01-30 23:10:18 +0000480 // fold (fneg (fadd A, B)) -> (fsub (fneg A), B)
Nick Lewycky8a8d4792011-12-02 22:16:29 +0000481 if (isNegatibleForFree(Op.getOperand(0), LegalOperations,
Owen Andersonafd3d562012-03-06 00:29:31 +0000482 DAG.getTargetLoweringInfo(),
Nick Lewycky8a8d4792011-12-02 22:16:29 +0000483 &DAG.getTarget().Options, Depth+1))
Bill Wendling35247c32009-01-30 00:45:56 +0000484 return DAG.getNode(ISD::FSUB, Op.getDebugLoc(), Op.getValueType(),
Scott Michelfdc40a02009-02-17 22:15:04 +0000485 GetNegatedExpression(Op.getOperand(0), DAG,
Duncan Sands25cf2272008-11-24 14:53:14 +0000486 LegalOperations, Depth+1),
Chris Lattner29446522007-05-14 22:04:50 +0000487 Op.getOperand(1));
Bill Wendlingd34470c2009-01-30 23:10:18 +0000488 // fold (fneg (fadd A, B)) -> (fsub (fneg B), A)
Bill Wendling35247c32009-01-30 00:45:56 +0000489 return DAG.getNode(ISD::FSUB, Op.getDebugLoc(), Op.getValueType(),
Scott Michelfdc40a02009-02-17 22:15:04 +0000490 GetNegatedExpression(Op.getOperand(1), DAG,
Duncan Sands25cf2272008-11-24 14:53:14 +0000491 LegalOperations, Depth+1),
Chris Lattner29446522007-05-14 22:04:50 +0000492 Op.getOperand(0));
493 case ISD::FSUB:
Scott Michelfdc40a02009-02-17 22:15:04 +0000494 // We can't turn -(A-B) into B-A when we honor signed zeros.
Nick Lewycky8a8d4792011-12-02 22:16:29 +0000495 assert(DAG.getTarget().Options.UnsafeFPMath);
Dan Gohman23ff1822007-07-02 15:48:56 +0000496
Bill Wendlingd34470c2009-01-30 23:10:18 +0000497 // fold (fneg (fsub 0, B)) -> B
Dan Gohman23ff1822007-07-02 15:48:56 +0000498 if (ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(Op.getOperand(0)))
Dale Johannesenc4dd3c32007-08-31 23:34:27 +0000499 if (N0CFP->getValueAPF().isZero())
Dan Gohman23ff1822007-07-02 15:48:56 +0000500 return Op.getOperand(1);
Scott Michelfdc40a02009-02-17 22:15:04 +0000501
Bill Wendlingd34470c2009-01-30 23:10:18 +0000502 // fold (fneg (fsub A, B)) -> (fsub B, A)
Bill Wendling35247c32009-01-30 00:45:56 +0000503 return DAG.getNode(ISD::FSUB, Op.getDebugLoc(), Op.getValueType(),
504 Op.getOperand(1), Op.getOperand(0));
Scott Michelfdc40a02009-02-17 22:15:04 +0000505
Chris Lattner29446522007-05-14 22:04:50 +0000506 case ISD::FMUL:
507 case ISD::FDIV:
Nick Lewycky8a8d4792011-12-02 22:16:29 +0000508 assert(!DAG.getTarget().Options.HonorSignDependentRoundingFPMath());
Scott Michelfdc40a02009-02-17 22:15:04 +0000509
Bill Wendlingd34470c2009-01-30 23:10:18 +0000510 // fold (fneg (fmul X, Y)) -> (fmul (fneg X), Y)
Nick Lewycky8a8d4792011-12-02 22:16:29 +0000511 if (isNegatibleForFree(Op.getOperand(0), LegalOperations,
Owen Andersonafd3d562012-03-06 00:29:31 +0000512 DAG.getTargetLoweringInfo(),
Nick Lewycky8a8d4792011-12-02 22:16:29 +0000513 &DAG.getTarget().Options, Depth+1))
Bill Wendling35247c32009-01-30 00:45:56 +0000514 return DAG.getNode(Op.getOpcode(), Op.getDebugLoc(), Op.getValueType(),
Scott Michelfdc40a02009-02-17 22:15:04 +0000515 GetNegatedExpression(Op.getOperand(0), DAG,
Duncan Sands25cf2272008-11-24 14:53:14 +0000516 LegalOperations, Depth+1),
Chris Lattner29446522007-05-14 22:04:50 +0000517 Op.getOperand(1));
Scott Michelfdc40a02009-02-17 22:15:04 +0000518
Bill Wendlingd34470c2009-01-30 23:10:18 +0000519 // fold (fneg (fmul X, Y)) -> (fmul X, (fneg Y))
Bill Wendling35247c32009-01-30 00:45:56 +0000520 return DAG.getNode(Op.getOpcode(), Op.getDebugLoc(), Op.getValueType(),
Chris Lattner29446522007-05-14 22:04:50 +0000521 Op.getOperand(0),
Chris Lattner0254e702008-02-26 07:04:54 +0000522 GetNegatedExpression(Op.getOperand(1), DAG,
Duncan Sands25cf2272008-11-24 14:53:14 +0000523 LegalOperations, Depth+1));
Scott Michelfdc40a02009-02-17 22:15:04 +0000524
Chris Lattner29446522007-05-14 22:04:50 +0000525 case ISD::FP_EXTEND:
Chris Lattner29446522007-05-14 22:04:50 +0000526 case ISD::FSIN:
Bill Wendling35247c32009-01-30 00:45:56 +0000527 return DAG.getNode(Op.getOpcode(), Op.getDebugLoc(), Op.getValueType(),
Scott Michelfdc40a02009-02-17 22:15:04 +0000528 GetNegatedExpression(Op.getOperand(0), DAG,
Duncan Sands25cf2272008-11-24 14:53:14 +0000529 LegalOperations, Depth+1));
Chris Lattner0bd48932008-01-17 07:00:52 +0000530 case ISD::FP_ROUND:
Bill Wendling35247c32009-01-30 00:45:56 +0000531 return DAG.getNode(ISD::FP_ROUND, Op.getDebugLoc(), Op.getValueType(),
Scott Michelfdc40a02009-02-17 22:15:04 +0000532 GetNegatedExpression(Op.getOperand(0), DAG,
Duncan Sands25cf2272008-11-24 14:53:14 +0000533 LegalOperations, Depth+1),
Chris Lattner0bd48932008-01-17 07:00:52 +0000534 Op.getOperand(1));
Chris Lattner29446522007-05-14 22:04:50 +0000535 }
536}
Chris Lattner24664722006-03-01 04:53:38 +0000537
538
Nate Begeman4ebd8052005-09-01 23:24:04 +0000539// isSetCCEquivalent - Return true if this node is a setcc, or is a select_cc
540// that selects between the values 1 and 0, making it equivalent to a setcc.
Scott Michelfdc40a02009-02-17 22:15:04 +0000541// Also, set the incoming LHS, RHS, and CC references to the appropriate
Nate Begeman646d7e22005-09-02 21:18:40 +0000542// nodes based on the type of node we are checking. This simplifies life a
543// bit for the callers.
Dan Gohman475871a2008-07-27 21:46:04 +0000544static bool isSetCCEquivalent(SDValue N, SDValue &LHS, SDValue &RHS,
545 SDValue &CC) {
Nate Begeman646d7e22005-09-02 21:18:40 +0000546 if (N.getOpcode() == ISD::SETCC) {
547 LHS = N.getOperand(0);
548 RHS = N.getOperand(1);
549 CC = N.getOperand(2);
Nate Begeman4ebd8052005-09-01 23:24:04 +0000550 return true;
Nate Begeman646d7e22005-09-02 21:18:40 +0000551 }
Scott Michelfdc40a02009-02-17 22:15:04 +0000552 if (N.getOpcode() == ISD::SELECT_CC &&
Nate Begeman1d4d4142005-09-01 00:19:25 +0000553 N.getOperand(2).getOpcode() == ISD::Constant &&
554 N.getOperand(3).getOpcode() == ISD::Constant &&
Dan Gohman002e5d02008-03-13 22:13:53 +0000555 cast<ConstantSDNode>(N.getOperand(2))->getAPIntValue() == 1 &&
Nate Begeman646d7e22005-09-02 21:18:40 +0000556 cast<ConstantSDNode>(N.getOperand(3))->isNullValue()) {
557 LHS = N.getOperand(0);
558 RHS = N.getOperand(1);
559 CC = N.getOperand(4);
Nate Begeman1d4d4142005-09-01 00:19:25 +0000560 return true;
Nate Begeman646d7e22005-09-02 21:18:40 +0000561 }
Nate Begeman1d4d4142005-09-01 00:19:25 +0000562 return false;
563}
564
Nate Begeman99801192005-09-07 23:25:52 +0000565// isOneUseSetCC - Return true if this is a SetCC-equivalent operation with only
566// one use. If this is true, it allows the users to invert the operation for
567// free when it is profitable to do so.
Dan Gohman475871a2008-07-27 21:46:04 +0000568static bool isOneUseSetCC(SDValue N) {
569 SDValue N0, N1, N2;
Gabor Greifba36cb52008-08-28 21:40:38 +0000570 if (isSetCCEquivalent(N, N0, N1, N2) && N.getNode()->hasOneUse())
Nate Begeman4ebd8052005-09-01 23:24:04 +0000571 return true;
572 return false;
573}
574
Bill Wendling35247c32009-01-30 00:45:56 +0000575SDValue DAGCombiner::ReassociateOps(unsigned Opc, DebugLoc DL,
576 SDValue N0, SDValue N1) {
Owen Andersone50ed302009-08-10 22:56:29 +0000577 EVT VT = N0.getValueType();
Nate Begemancd4d58c2006-02-03 06:46:56 +0000578 if (N0.getOpcode() == Opc && isa<ConstantSDNode>(N0.getOperand(1))) {
579 if (isa<ConstantSDNode>(N1)) {
Bill Wendling35247c32009-01-30 00:45:56 +0000580 // reassoc. (op (op x, c1), c2) -> (op x, (op c1, c2))
Bill Wendling6af76182009-01-30 20:50:00 +0000581 SDValue OpNode =
582 DAG.FoldConstantArithmetic(Opc, VT,
583 cast<ConstantSDNode>(N0.getOperand(1)),
584 cast<ConstantSDNode>(N1));
Bill Wendlingd69c3142009-01-30 02:23:43 +0000585 return DAG.getNode(Opc, DL, VT, N0.getOperand(0), OpNode);
Dan Gohman71dc7c92011-05-17 22:20:36 +0000586 }
587 if (N0.hasOneUse()) {
Sylvestre Ledru94c22712012-09-27 10:14:43 +0000588 // reassoc. (op (op x, c1), y) -> (op (op x, y), c1) iff x+c1 has one use
Bill Wendling35247c32009-01-30 00:45:56 +0000589 SDValue OpNode = DAG.getNode(Opc, N0.getDebugLoc(), VT,
590 N0.getOperand(0), N1);
Gabor Greifba36cb52008-08-28 21:40:38 +0000591 AddToWorkList(OpNode.getNode());
Bill Wendling35247c32009-01-30 00:45:56 +0000592 return DAG.getNode(Opc, DL, VT, OpNode, N0.getOperand(1));
Nate Begemancd4d58c2006-02-03 06:46:56 +0000593 }
594 }
Bill Wendling35247c32009-01-30 00:45:56 +0000595
Nate Begemancd4d58c2006-02-03 06:46:56 +0000596 if (N1.getOpcode() == Opc && isa<ConstantSDNode>(N1.getOperand(1))) {
597 if (isa<ConstantSDNode>(N0)) {
Bill Wendling35247c32009-01-30 00:45:56 +0000598 // reassoc. (op c2, (op x, c1)) -> (op x, (op c1, c2))
Bill Wendling6af76182009-01-30 20:50:00 +0000599 SDValue OpNode =
600 DAG.FoldConstantArithmetic(Opc, VT,
601 cast<ConstantSDNode>(N1.getOperand(1)),
602 cast<ConstantSDNode>(N0));
Bill Wendlingd69c3142009-01-30 02:23:43 +0000603 return DAG.getNode(Opc, DL, VT, N1.getOperand(0), OpNode);
Dan Gohman71dc7c92011-05-17 22:20:36 +0000604 }
605 if (N1.hasOneUse()) {
Sylvestre Ledru94c22712012-09-27 10:14:43 +0000606 // reassoc. (op y, (op x, c1)) -> (op (op x, y), c1) iff x+c1 has one use
Bill Wendlingd69c3142009-01-30 02:23:43 +0000607 SDValue OpNode = DAG.getNode(Opc, N0.getDebugLoc(), VT,
Bill Wendling35247c32009-01-30 00:45:56 +0000608 N1.getOperand(0), N0);
Gabor Greifba36cb52008-08-28 21:40:38 +0000609 AddToWorkList(OpNode.getNode());
Bill Wendling35247c32009-01-30 00:45:56 +0000610 return DAG.getNode(Opc, DL, VT, OpNode, N1.getOperand(1));
Nate Begemancd4d58c2006-02-03 06:46:56 +0000611 }
612 }
Bill Wendling35247c32009-01-30 00:45:56 +0000613
Dan Gohman475871a2008-07-27 21:46:04 +0000614 return SDValue();
Nate Begemancd4d58c2006-02-03 06:46:56 +0000615}
616
Dan Gohman475871a2008-07-27 21:46:04 +0000617SDValue DAGCombiner::CombineTo(SDNode *N, const SDValue *To, unsigned NumTo,
618 bool AddTo) {
Chris Lattnerf8dc0612008-02-03 06:49:24 +0000619 assert(N->getNumValues() == NumTo && "Broken CombineTo call!");
620 ++NodesCombined;
David Greenef1090292010-01-05 01:25:00 +0000621 DEBUG(dbgs() << "\nReplacing.1 ";
Chris Lattnerbbbfa992009-08-23 06:35:02 +0000622 N->dump(&DAG);
David Greenef1090292010-01-05 01:25:00 +0000623 dbgs() << "\nWith: ";
Chris Lattnerbbbfa992009-08-23 06:35:02 +0000624 To[0].getNode()->dump(&DAG);
David Greenef1090292010-01-05 01:25:00 +0000625 dbgs() << " and " << NumTo-1 << " other values\n";
Chris Lattnerbbbfa992009-08-23 06:35:02 +0000626 for (unsigned i = 0, e = NumTo; i != e; ++i)
Jakob Stoklund Olesen9f0d4e62009-12-03 05:15:35 +0000627 assert((!To[i].getNode() ||
628 N->getValueType(i) == To[i].getValueType()) &&
Dan Gohman764fd0c2009-01-21 15:17:51 +0000629 "Cannot combine value to value of different type!"));
Chris Lattnerf8dc0612008-02-03 06:49:24 +0000630 WorkListRemover DeadNodes(*this);
Jakob Stoklund Olesenbc7d4482012-04-20 22:08:46 +0000631 DAG.ReplaceAllUsesWith(N, To);
Chris Lattnerf8dc0612008-02-03 06:49:24 +0000632 if (AddTo) {
633 // Push the new nodes and any users onto the worklist
634 for (unsigned i = 0, e = NumTo; i != e; ++i) {
Chris Lattnerd1980a52009-03-12 06:52:53 +0000635 if (To[i].getNode()) {
636 AddToWorkList(To[i].getNode());
637 AddUsersToWorkList(To[i].getNode());
638 }
Chris Lattnerf8dc0612008-02-03 06:49:24 +0000639 }
640 }
Scott Michelfdc40a02009-02-17 22:15:04 +0000641
Dan Gohmandbe664a2009-01-19 21:44:21 +0000642 // Finally, if the node is now dead, remove it from the graph. The node
643 // may not be dead if the replacement process recursively simplified to
644 // something else needing this node.
645 if (N->use_empty()) {
646 // Nodes can be reintroduced into the worklist. Make sure we do not
647 // process a node that has been replaced.
648 removeFromWorkList(N);
Scott Michelfdc40a02009-02-17 22:15:04 +0000649
Dan Gohmandbe664a2009-01-19 21:44:21 +0000650 // Finally, since the node is now dead, remove it from the graph.
651 DAG.DeleteNode(N);
652 }
Dan Gohman475871a2008-07-27 21:46:04 +0000653 return SDValue(N, 0);
Chris Lattnerf8dc0612008-02-03 06:49:24 +0000654}
655
Evan Chenge5b51ac2010-04-17 06:13:15 +0000656void DAGCombiner::
657CommitTargetLoweringOpt(const TargetLowering::TargetLoweringOpt &TLO) {
Scott Michelfdc40a02009-02-17 22:15:04 +0000658 // Replace all uses. If any nodes become isomorphic to other nodes and
Chris Lattnerf8dc0612008-02-03 06:49:24 +0000659 // are deleted, make sure to remove them from our worklist.
660 WorkListRemover DeadNodes(*this);
Jakob Stoklund Olesenbc7d4482012-04-20 22:08:46 +0000661 DAG.ReplaceAllUsesOfValueWith(TLO.Old, TLO.New);
Dan Gohmane5af2d32009-01-29 01:59:02 +0000662
Chris Lattnerf8dc0612008-02-03 06:49:24 +0000663 // Push the new node and any (possibly new) users onto the worklist.
Gabor Greifba36cb52008-08-28 21:40:38 +0000664 AddToWorkList(TLO.New.getNode());
665 AddUsersToWorkList(TLO.New.getNode());
Scott Michelfdc40a02009-02-17 22:15:04 +0000666
Chris Lattnerf8dc0612008-02-03 06:49:24 +0000667 // Finally, if the node is now dead, remove it from the graph. The node
668 // may not be dead if the replacement process recursively simplified to
669 // something else needing this node.
Gabor Greifba36cb52008-08-28 21:40:38 +0000670 if (TLO.Old.getNode()->use_empty()) {
671 removeFromWorkList(TLO.Old.getNode());
Scott Michelfdc40a02009-02-17 22:15:04 +0000672
Chris Lattnerf8dc0612008-02-03 06:49:24 +0000673 // If the operands of this node are only used by the node, they will now
674 // be dead. Make sure to visit them first to delete dead nodes early.
Gabor Greifba36cb52008-08-28 21:40:38 +0000675 for (unsigned i = 0, e = TLO.Old.getNode()->getNumOperands(); i != e; ++i)
676 if (TLO.Old.getNode()->getOperand(i).getNode()->hasOneUse())
677 AddToWorkList(TLO.Old.getNode()->getOperand(i).getNode());
Scott Michelfdc40a02009-02-17 22:15:04 +0000678
Gabor Greifba36cb52008-08-28 21:40:38 +0000679 DAG.DeleteNode(TLO.Old.getNode());
Chris Lattnerf8dc0612008-02-03 06:49:24 +0000680 }
Dan Gohmane5af2d32009-01-29 01:59:02 +0000681}
682
683/// SimplifyDemandedBits - Check the specified integer node value to see if
684/// it can be simplified or if things it uses can be simplified by bit
685/// propagation. If so, return true.
686bool DAGCombiner::SimplifyDemandedBits(SDValue Op, const APInt &Demanded) {
Evan Chenge5b51ac2010-04-17 06:13:15 +0000687 TargetLowering::TargetLoweringOpt TLO(DAG, LegalTypes, LegalOperations);
Dan Gohmane5af2d32009-01-29 01:59:02 +0000688 APInt KnownZero, KnownOne;
689 if (!TLI.SimplifyDemandedBits(Op, Demanded, KnownZero, KnownOne, TLO))
690 return false;
Scott Michelfdc40a02009-02-17 22:15:04 +0000691
Dan Gohmane5af2d32009-01-29 01:59:02 +0000692 // Revisit the node.
693 AddToWorkList(Op.getNode());
Scott Michelfdc40a02009-02-17 22:15:04 +0000694
Dan Gohmane5af2d32009-01-29 01:59:02 +0000695 // Replace the old value with the new one.
696 ++NodesCombined;
Wesley Peckbf17cfa2010-11-23 03:31:01 +0000697 DEBUG(dbgs() << "\nReplacing.2 ";
Chris Lattnerbbbfa992009-08-23 06:35:02 +0000698 TLO.Old.getNode()->dump(&DAG);
David Greenef1090292010-01-05 01:25:00 +0000699 dbgs() << "\nWith: ";
Chris Lattnerbbbfa992009-08-23 06:35:02 +0000700 TLO.New.getNode()->dump(&DAG);
David Greenef1090292010-01-05 01:25:00 +0000701 dbgs() << '\n');
Scott Michelfdc40a02009-02-17 22:15:04 +0000702
Dan Gohmane5af2d32009-01-29 01:59:02 +0000703 CommitTargetLoweringOpt(TLO);
Chris Lattnerf8dc0612008-02-03 06:49:24 +0000704 return true;
705}
706
Evan Cheng95c57ea2010-04-24 04:43:44 +0000707void DAGCombiner::ReplaceLoadWithPromotedLoad(SDNode *Load, SDNode *ExtLoad) {
708 DebugLoc dl = Load->getDebugLoc();
709 EVT VT = Load->getValueType(0);
710 SDValue Trunc = DAG.getNode(ISD::TRUNCATE, dl, VT, SDValue(ExtLoad, 0));
Evan Cheng4c26e932010-04-19 19:29:22 +0000711
Evan Cheng95c57ea2010-04-24 04:43:44 +0000712 DEBUG(dbgs() << "\nReplacing.9 ";
713 Load->dump(&DAG);
714 dbgs() << "\nWith: ";
715 Trunc.getNode()->dump(&DAG);
716 dbgs() << '\n');
717 WorkListRemover DeadNodes(*this);
Jakob Stoklund Olesenbc7d4482012-04-20 22:08:46 +0000718 DAG.ReplaceAllUsesOfValueWith(SDValue(Load, 0), Trunc);
719 DAG.ReplaceAllUsesOfValueWith(SDValue(Load, 1), SDValue(ExtLoad, 1));
Evan Cheng95c57ea2010-04-24 04:43:44 +0000720 removeFromWorkList(Load);
721 DAG.DeleteNode(Load);
Evan Chengac7eae52010-04-27 19:48:13 +0000722 AddToWorkList(Trunc.getNode());
Evan Cheng95c57ea2010-04-24 04:43:44 +0000723}
724
725SDValue DAGCombiner::PromoteOperand(SDValue Op, EVT PVT, bool &Replace) {
726 Replace = false;
Evan Cheng4c26e932010-04-19 19:29:22 +0000727 DebugLoc dl = Op.getDebugLoc();
Evan Chenge5b51ac2010-04-17 06:13:15 +0000728 if (LoadSDNode *LD = dyn_cast<LoadSDNode>(Op)) {
Evan Chengac7eae52010-04-27 19:48:13 +0000729 EVT MemVT = LD->getMemoryVT();
730 ISD::LoadExtType ExtType = ISD::isNON_EXTLoad(LD)
Owen Anderson95771af2011-02-25 21:41:48 +0000731 ? (TLI.isLoadExtLegal(ISD::ZEXTLOAD, MemVT) ? ISD::ZEXTLOAD
Eric Christopher503a64d2010-12-09 04:48:06 +0000732 : ISD::EXTLOAD)
Evan Chengac7eae52010-04-27 19:48:13 +0000733 : LD->getExtensionType();
Evan Cheng95c57ea2010-04-24 04:43:44 +0000734 Replace = true;
Stuart Hastingsa9011292011-02-16 16:23:55 +0000735 return DAG.getExtLoad(ExtType, dl, PVT,
Evan Chenge5b51ac2010-04-17 06:13:15 +0000736 LD->getChain(), LD->getBasePtr(),
Chris Lattner3d6ccfb2010-09-21 17:04:51 +0000737 LD->getPointerInfo(),
Evan Chengac7eae52010-04-27 19:48:13 +0000738 MemVT, LD->isVolatile(),
Evan Chenge5b51ac2010-04-17 06:13:15 +0000739 LD->isNonTemporal(), LD->getAlignment());
740 }
741
Evan Cheng4c26e932010-04-19 19:29:22 +0000742 unsigned Opc = Op.getOpcode();
Evan Chengcaf77402010-04-23 19:10:30 +0000743 switch (Opc) {
744 default: break;
745 case ISD::AssertSext:
Evan Cheng4c26e932010-04-19 19:29:22 +0000746 return DAG.getNode(ISD::AssertSext, dl, PVT,
Evan Cheng95c57ea2010-04-24 04:43:44 +0000747 SExtPromoteOperand(Op.getOperand(0), PVT),
Evan Cheng4c26e932010-04-19 19:29:22 +0000748 Op.getOperand(1));
Evan Chengcaf77402010-04-23 19:10:30 +0000749 case ISD::AssertZext:
Evan Cheng4c26e932010-04-19 19:29:22 +0000750 return DAG.getNode(ISD::AssertZext, dl, PVT,
Evan Cheng95c57ea2010-04-24 04:43:44 +0000751 ZExtPromoteOperand(Op.getOperand(0), PVT),
Evan Cheng4c26e932010-04-19 19:29:22 +0000752 Op.getOperand(1));
Evan Chengcaf77402010-04-23 19:10:30 +0000753 case ISD::Constant: {
754 unsigned ExtOpc =
Evan Cheng4c26e932010-04-19 19:29:22 +0000755 Op.getValueType().isByteSized() ? ISD::SIGN_EXTEND : ISD::ZERO_EXTEND;
Evan Chengcaf77402010-04-23 19:10:30 +0000756 return DAG.getNode(ExtOpc, dl, PVT, Op);
Wesley Peckbf17cfa2010-11-23 03:31:01 +0000757 }
Evan Chengcaf77402010-04-23 19:10:30 +0000758 }
759
760 if (!TLI.isOperationLegal(ISD::ANY_EXTEND, PVT))
Evan Chenge5b51ac2010-04-17 06:13:15 +0000761 return SDValue();
Evan Chengcaf77402010-04-23 19:10:30 +0000762 return DAG.getNode(ISD::ANY_EXTEND, dl, PVT, Op);
Evan Cheng64b7bf72010-04-16 06:14:10 +0000763}
764
Evan Cheng95c57ea2010-04-24 04:43:44 +0000765SDValue DAGCombiner::SExtPromoteOperand(SDValue Op, EVT PVT) {
Evan Chenge5b51ac2010-04-17 06:13:15 +0000766 if (!TLI.isOperationLegal(ISD::SIGN_EXTEND_INREG, PVT))
767 return SDValue();
768 EVT OldVT = Op.getValueType();
769 DebugLoc dl = Op.getDebugLoc();
Evan Cheng95c57ea2010-04-24 04:43:44 +0000770 bool Replace = false;
771 SDValue NewOp = PromoteOperand(Op, PVT, Replace);
772 if (NewOp.getNode() == 0)
Evan Chenge5b51ac2010-04-17 06:13:15 +0000773 return SDValue();
Evan Chengac7eae52010-04-27 19:48:13 +0000774 AddToWorkList(NewOp.getNode());
Evan Cheng95c57ea2010-04-24 04:43:44 +0000775
776 if (Replace)
777 ReplaceLoadWithPromotedLoad(Op.getNode(), NewOp.getNode());
778 return DAG.getNode(ISD::SIGN_EXTEND_INREG, dl, NewOp.getValueType(), NewOp,
Evan Chenge5b51ac2010-04-17 06:13:15 +0000779 DAG.getValueType(OldVT));
780}
781
Evan Cheng95c57ea2010-04-24 04:43:44 +0000782SDValue DAGCombiner::ZExtPromoteOperand(SDValue Op, EVT PVT) {
Evan Chenge5b51ac2010-04-17 06:13:15 +0000783 EVT OldVT = Op.getValueType();
784 DebugLoc dl = Op.getDebugLoc();
Evan Cheng95c57ea2010-04-24 04:43:44 +0000785 bool Replace = false;
786 SDValue NewOp = PromoteOperand(Op, PVT, Replace);
787 if (NewOp.getNode() == 0)
Evan Chenge5b51ac2010-04-17 06:13:15 +0000788 return SDValue();
Evan Chengac7eae52010-04-27 19:48:13 +0000789 AddToWorkList(NewOp.getNode());
Evan Cheng95c57ea2010-04-24 04:43:44 +0000790
791 if (Replace)
792 ReplaceLoadWithPromotedLoad(Op.getNode(), NewOp.getNode());
793 return DAG.getZeroExtendInReg(NewOp, dl, OldVT);
Evan Chenge5b51ac2010-04-17 06:13:15 +0000794}
795
Evan Cheng64b7bf72010-04-16 06:14:10 +0000796/// PromoteIntBinOp - Promote the specified integer binary operation if the
797/// target indicates it is beneficial. e.g. On x86, it's usually better to
798/// promote i16 operations to i32 since i16 instructions are longer.
799SDValue DAGCombiner::PromoteIntBinOp(SDValue Op) {
800 if (!LegalOperations)
801 return SDValue();
802
803 EVT VT = Op.getValueType();
804 if (VT.isVector() || !VT.isInteger())
805 return SDValue();
806
Evan Chenge5b51ac2010-04-17 06:13:15 +0000807 // If operation type is 'undesirable', e.g. i16 on x86, consider
808 // promoting it.
809 unsigned Opc = Op.getOpcode();
810 if (TLI.isTypeDesirableForOp(Opc, VT))
811 return SDValue();
812
Evan Cheng64b7bf72010-04-16 06:14:10 +0000813 EVT PVT = VT;
Evan Chenge5b51ac2010-04-17 06:13:15 +0000814 // Consult target whether it is a good idea to promote this operation and
815 // what's the right type to promote it to.
816 if (TLI.IsDesirableToPromoteOp(Op, PVT)) {
Evan Cheng64b7bf72010-04-16 06:14:10 +0000817 assert(PVT != VT && "Don't know what type to promote to!");
818
Evan Cheng95c57ea2010-04-24 04:43:44 +0000819 bool Replace0 = false;
820 SDValue N0 = Op.getOperand(0);
821 SDValue NN0 = PromoteOperand(N0, PVT, Replace0);
822 if (NN0.getNode() == 0)
Evan Cheng07c4e102010-04-22 20:19:46 +0000823 return SDValue();
824
Evan Cheng95c57ea2010-04-24 04:43:44 +0000825 bool Replace1 = false;
826 SDValue N1 = Op.getOperand(1);
Evan Chengaad753b2010-05-10 19:03:57 +0000827 SDValue NN1;
828 if (N0 == N1)
829 NN1 = NN0;
830 else {
831 NN1 = PromoteOperand(N1, PVT, Replace1);
832 if (NN1.getNode() == 0)
833 return SDValue();
834 }
Evan Cheng07c4e102010-04-22 20:19:46 +0000835
Evan Cheng95c57ea2010-04-24 04:43:44 +0000836 AddToWorkList(NN0.getNode());
Evan Chengaad753b2010-05-10 19:03:57 +0000837 if (NN1.getNode())
838 AddToWorkList(NN1.getNode());
Evan Cheng95c57ea2010-04-24 04:43:44 +0000839
840 if (Replace0)
841 ReplaceLoadWithPromotedLoad(N0.getNode(), NN0.getNode());
842 if (Replace1)
843 ReplaceLoadWithPromotedLoad(N1.getNode(), NN1.getNode());
Evan Cheng07c4e102010-04-22 20:19:46 +0000844
Evan Chengac7eae52010-04-27 19:48:13 +0000845 DEBUG(dbgs() << "\nPromoting ";
846 Op.getNode()->dump(&DAG));
Evan Cheng07c4e102010-04-22 20:19:46 +0000847 DebugLoc dl = Op.getDebugLoc();
848 return DAG.getNode(ISD::TRUNCATE, dl, VT,
Evan Cheng95c57ea2010-04-24 04:43:44 +0000849 DAG.getNode(Opc, dl, PVT, NN0, NN1));
Evan Cheng07c4e102010-04-22 20:19:46 +0000850 }
851 return SDValue();
852}
853
854/// PromoteIntShiftOp - Promote the specified integer shift operation if the
855/// target indicates it is beneficial. e.g. On x86, it's usually better to
856/// promote i16 operations to i32 since i16 instructions are longer.
857SDValue DAGCombiner::PromoteIntShiftOp(SDValue Op) {
858 if (!LegalOperations)
859 return SDValue();
860
861 EVT VT = Op.getValueType();
862 if (VT.isVector() || !VT.isInteger())
863 return SDValue();
864
865 // If operation type is 'undesirable', e.g. i16 on x86, consider
866 // promoting it.
867 unsigned Opc = Op.getOpcode();
868 if (TLI.isTypeDesirableForOp(Opc, VT))
869 return SDValue();
870
871 EVT PVT = VT;
872 // Consult target whether it is a good idea to promote this operation and
873 // what's the right type to promote it to.
874 if (TLI.IsDesirableToPromoteOp(Op, PVT)) {
875 assert(PVT != VT && "Don't know what type to promote to!");
876
Evan Cheng95c57ea2010-04-24 04:43:44 +0000877 bool Replace = false;
Evan Chenge5b51ac2010-04-17 06:13:15 +0000878 SDValue N0 = Op.getOperand(0);
879 if (Opc == ISD::SRA)
Evan Cheng95c57ea2010-04-24 04:43:44 +0000880 N0 = SExtPromoteOperand(Op.getOperand(0), PVT);
Evan Chenge5b51ac2010-04-17 06:13:15 +0000881 else if (Opc == ISD::SRL)
Evan Cheng95c57ea2010-04-24 04:43:44 +0000882 N0 = ZExtPromoteOperand(Op.getOperand(0), PVT);
Evan Chenge5b51ac2010-04-17 06:13:15 +0000883 else
Evan Cheng95c57ea2010-04-24 04:43:44 +0000884 N0 = PromoteOperand(N0, PVT, Replace);
Evan Chenge5b51ac2010-04-17 06:13:15 +0000885 if (N0.getNode() == 0)
886 return SDValue();
Evan Cheng95c57ea2010-04-24 04:43:44 +0000887
Evan Chenge5b51ac2010-04-17 06:13:15 +0000888 AddToWorkList(N0.getNode());
Evan Cheng95c57ea2010-04-24 04:43:44 +0000889 if (Replace)
890 ReplaceLoadWithPromotedLoad(Op.getOperand(0).getNode(), N0.getNode());
Evan Cheng64b7bf72010-04-16 06:14:10 +0000891
Evan Chengac7eae52010-04-27 19:48:13 +0000892 DEBUG(dbgs() << "\nPromoting ";
893 Op.getNode()->dump(&DAG));
Evan Cheng64b7bf72010-04-16 06:14:10 +0000894 DebugLoc dl = Op.getDebugLoc();
895 return DAG.getNode(ISD::TRUNCATE, dl, VT,
Evan Cheng07c4e102010-04-22 20:19:46 +0000896 DAG.getNode(Opc, dl, PVT, N0, Op.getOperand(1)));
Evan Cheng64b7bf72010-04-16 06:14:10 +0000897 }
898 return SDValue();
899}
900
Evan Cheng4c26e932010-04-19 19:29:22 +0000901SDValue DAGCombiner::PromoteExtend(SDValue Op) {
902 if (!LegalOperations)
903 return SDValue();
904
905 EVT VT = Op.getValueType();
906 if (VT.isVector() || !VT.isInteger())
907 return SDValue();
908
909 // If operation type is 'undesirable', e.g. i16 on x86, consider
910 // promoting it.
911 unsigned Opc = Op.getOpcode();
912 if (TLI.isTypeDesirableForOp(Opc, VT))
913 return SDValue();
914
915 EVT PVT = VT;
916 // Consult target whether it is a good idea to promote this operation and
917 // what's the right type to promote it to.
918 if (TLI.IsDesirableToPromoteOp(Op, PVT)) {
919 assert(PVT != VT && "Don't know what type to promote to!");
920 // fold (aext (aext x)) -> (aext x)
921 // fold (aext (zext x)) -> (zext x)
922 // fold (aext (sext x)) -> (sext x)
Evan Chengac7eae52010-04-27 19:48:13 +0000923 DEBUG(dbgs() << "\nPromoting ";
924 Op.getNode()->dump(&DAG));
Evan Cheng4c26e932010-04-19 19:29:22 +0000925 return DAG.getNode(Op.getOpcode(), Op.getDebugLoc(), VT, Op.getOperand(0));
926 }
927 return SDValue();
928}
929
930bool DAGCombiner::PromoteLoad(SDValue Op) {
931 if (!LegalOperations)
932 return false;
933
934 EVT VT = Op.getValueType();
935 if (VT.isVector() || !VT.isInteger())
936 return false;
937
938 // If operation type is 'undesirable', e.g. i16 on x86, consider
939 // promoting it.
940 unsigned Opc = Op.getOpcode();
941 if (TLI.isTypeDesirableForOp(Opc, VT))
942 return false;
943
944 EVT PVT = VT;
945 // Consult target whether it is a good idea to promote this operation and
946 // what's the right type to promote it to.
947 if (TLI.IsDesirableToPromoteOp(Op, PVT)) {
948 assert(PVT != VT && "Don't know what type to promote to!");
949
950 DebugLoc dl = Op.getDebugLoc();
951 SDNode *N = Op.getNode();
952 LoadSDNode *LD = cast<LoadSDNode>(N);
Evan Chengac7eae52010-04-27 19:48:13 +0000953 EVT MemVT = LD->getMemoryVT();
954 ISD::LoadExtType ExtType = ISD::isNON_EXTLoad(LD)
Owen Anderson95771af2011-02-25 21:41:48 +0000955 ? (TLI.isLoadExtLegal(ISD::ZEXTLOAD, MemVT) ? ISD::ZEXTLOAD
Eric Christopher503a64d2010-12-09 04:48:06 +0000956 : ISD::EXTLOAD)
Evan Chengac7eae52010-04-27 19:48:13 +0000957 : LD->getExtensionType();
Stuart Hastingsa9011292011-02-16 16:23:55 +0000958 SDValue NewLD = DAG.getExtLoad(ExtType, dl, PVT,
Evan Cheng4c26e932010-04-19 19:29:22 +0000959 LD->getChain(), LD->getBasePtr(),
Chris Lattner3d6ccfb2010-09-21 17:04:51 +0000960 LD->getPointerInfo(),
Evan Chengac7eae52010-04-27 19:48:13 +0000961 MemVT, LD->isVolatile(),
Evan Cheng4c26e932010-04-19 19:29:22 +0000962 LD->isNonTemporal(), LD->getAlignment());
963 SDValue Result = DAG.getNode(ISD::TRUNCATE, dl, VT, NewLD);
964
Evan Cheng95c57ea2010-04-24 04:43:44 +0000965 DEBUG(dbgs() << "\nPromoting ";
Evan Cheng4c26e932010-04-19 19:29:22 +0000966 N->dump(&DAG);
Evan Cheng95c57ea2010-04-24 04:43:44 +0000967 dbgs() << "\nTo: ";
Evan Cheng4c26e932010-04-19 19:29:22 +0000968 Result.getNode()->dump(&DAG);
969 dbgs() << '\n');
970 WorkListRemover DeadNodes(*this);
Jakob Stoklund Olesenbc7d4482012-04-20 22:08:46 +0000971 DAG.ReplaceAllUsesOfValueWith(SDValue(N, 0), Result);
972 DAG.ReplaceAllUsesOfValueWith(SDValue(N, 1), NewLD.getValue(1));
Evan Cheng4c26e932010-04-19 19:29:22 +0000973 removeFromWorkList(N);
974 DAG.DeleteNode(N);
Evan Chengac7eae52010-04-27 19:48:13 +0000975 AddToWorkList(Result.getNode());
Evan Cheng4c26e932010-04-19 19:29:22 +0000976 return true;
977 }
978 return false;
979}
980
Evan Chenge5b51ac2010-04-17 06:13:15 +0000981
Chris Lattner29446522007-05-14 22:04:50 +0000982//===----------------------------------------------------------------------===//
983// Main DAG Combiner implementation
984//===----------------------------------------------------------------------===//
985
Duncan Sands25cf2272008-11-24 14:53:14 +0000986void DAGCombiner::Run(CombineLevel AtLevel) {
987 // set the instance variables, so that the various visit routines may use it.
988 Level = AtLevel;
Eli Friedman50185242011-11-12 00:35:34 +0000989 LegalOperations = Level >= AfterLegalizeVectorOps;
990 LegalTypes = Level >= AfterLegalizeTypes;
Nate Begeman4ebd8052005-09-01 23:24:04 +0000991
Evan Cheng17a568b2008-08-29 22:21:44 +0000992 // Add all the dag nodes to the worklist.
Evan Cheng17a568b2008-08-29 22:21:44 +0000993 for (SelectionDAG::allnodes_iterator I = DAG.allnodes_begin(),
994 E = DAG.allnodes_end(); I != E; ++I)
James Molloy6660c052012-02-16 09:17:04 +0000995 AddToWorkList(I);
Duncan Sands25cf2272008-11-24 14:53:14 +0000996
Evan Cheng17a568b2008-08-29 22:21:44 +0000997 // Create a dummy node (which is not added to allnodes), that adds a reference
998 // to the root node, preventing it from being deleted, and tracking any
999 // changes of the root.
1000 HandleSDNode Dummy(DAG.getRoot());
Scott Michelfdc40a02009-02-17 22:15:04 +00001001
Jim Laskey26f7fa72006-10-17 19:33:52 +00001002 // The root of the dag may dangle to deleted nodes until the dag combiner is
1003 // done. Set it to null to avoid confusion.
Dan Gohman475871a2008-07-27 21:46:04 +00001004 DAG.setRoot(SDValue());
Scott Michelfdc40a02009-02-17 22:15:04 +00001005
James Molloy6660c052012-02-16 09:17:04 +00001006 // while the worklist isn't empty, find a node and
Evan Cheng17a568b2008-08-29 22:21:44 +00001007 // try and combine it.
James Molloy6660c052012-02-16 09:17:04 +00001008 while (!WorkListContents.empty()) {
1009 SDNode *N;
1010 // The WorkListOrder holds the SDNodes in order, but it may contain duplicates.
1011 // In order to avoid a linear scan, we use a set (O(log N)) to hold what the
1012 // worklist *should* contain, and check the node we want to visit is should
1013 // actually be visited.
1014 do {
Benjamin Kramerd5f76902012-03-10 00:23:58 +00001015 N = WorkListOrder.pop_back_val();
James Molloy6660c052012-02-16 09:17:04 +00001016 } while (!WorkListContents.erase(N));
Scott Michelfdc40a02009-02-17 22:15:04 +00001017
Evan Cheng17a568b2008-08-29 22:21:44 +00001018 // If N has no uses, it is dead. Make sure to revisit all N's operands once
1019 // N is deleted from the DAG, since they too may now be dead or may have a
1020 // reduced number of uses, allowing other xforms.
1021 if (N->use_empty() && N != &Dummy) {
1022 for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i)
1023 AddToWorkList(N->getOperand(i).getNode());
Scott Michelfdc40a02009-02-17 22:15:04 +00001024
Evan Cheng17a568b2008-08-29 22:21:44 +00001025 DAG.DeleteNode(N);
1026 continue;
Nate Begeman1d4d4142005-09-01 00:19:25 +00001027 }
Scott Michelfdc40a02009-02-17 22:15:04 +00001028
Evan Cheng17a568b2008-08-29 22:21:44 +00001029 SDValue RV = combine(N);
Scott Michelfdc40a02009-02-17 22:15:04 +00001030
Evan Cheng17a568b2008-08-29 22:21:44 +00001031 if (RV.getNode() == 0)
1032 continue;
Scott Michelfdc40a02009-02-17 22:15:04 +00001033
Evan Cheng17a568b2008-08-29 22:21:44 +00001034 ++NodesCombined;
Scott Michelfdc40a02009-02-17 22:15:04 +00001035
Evan Cheng17a568b2008-08-29 22:21:44 +00001036 // If we get back the same node we passed in, rather than a new node or
1037 // zero, we know that the node must have defined multiple values and
Scott Michelfdc40a02009-02-17 22:15:04 +00001038 // CombineTo was used. Since CombineTo takes care of the worklist
Evan Cheng17a568b2008-08-29 22:21:44 +00001039 // mechanics for us, we have no work to do in this case.
1040 if (RV.getNode() == N)
1041 continue;
Scott Michelfdc40a02009-02-17 22:15:04 +00001042
Evan Cheng17a568b2008-08-29 22:21:44 +00001043 assert(N->getOpcode() != ISD::DELETED_NODE &&
1044 RV.getNode()->getOpcode() != ISD::DELETED_NODE &&
1045 "Node was deleted but visit returned new node!");
Chris Lattner729c6d12006-05-27 00:43:02 +00001046
Wesley Peckbf17cfa2010-11-23 03:31:01 +00001047 DEBUG(dbgs() << "\nReplacing.3 ";
Chris Lattnerbbbfa992009-08-23 06:35:02 +00001048 N->dump(&DAG);
David Greenef1090292010-01-05 01:25:00 +00001049 dbgs() << "\nWith: ";
Chris Lattnerbbbfa992009-08-23 06:35:02 +00001050 RV.getNode()->dump(&DAG);
David Greenef1090292010-01-05 01:25:00 +00001051 dbgs() << '\n');
Eric Christopher7332e6e2011-07-14 01:12:15 +00001052
Devang Patel9728ea22011-05-23 22:04:42 +00001053 // Transfer debug value.
1054 DAG.TransferDbgValues(SDValue(N, 0), RV);
Evan Cheng17a568b2008-08-29 22:21:44 +00001055 WorkListRemover DeadNodes(*this);
1056 if (N->getNumValues() == RV.getNode()->getNumValues())
Jakob Stoklund Olesenbc7d4482012-04-20 22:08:46 +00001057 DAG.ReplaceAllUsesWith(N, RV.getNode());
Evan Cheng17a568b2008-08-29 22:21:44 +00001058 else {
1059 assert(N->getValueType(0) == RV.getValueType() &&
1060 N->getNumValues() == 1 && "Type mismatch");
1061 SDValue OpV = RV;
Jakob Stoklund Olesenbc7d4482012-04-20 22:08:46 +00001062 DAG.ReplaceAllUsesWith(N, &OpV);
Evan Cheng17a568b2008-08-29 22:21:44 +00001063 }
Scott Michelfdc40a02009-02-17 22:15:04 +00001064
Evan Cheng17a568b2008-08-29 22:21:44 +00001065 // Push the new node and any users onto the worklist
1066 AddToWorkList(RV.getNode());
1067 AddUsersToWorkList(RV.getNode());
Scott Michelfdc40a02009-02-17 22:15:04 +00001068
Evan Cheng17a568b2008-08-29 22:21:44 +00001069 // Add any uses of the old node to the worklist in case this node is the
1070 // last one that uses them. They may become dead after this node is
1071 // deleted.
1072 for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i)
1073 AddToWorkList(N->getOperand(i).getNode());
Scott Michelfdc40a02009-02-17 22:15:04 +00001074
Dan Gohmandbe664a2009-01-19 21:44:21 +00001075 // Finally, if the node is now dead, remove it from the graph. The node
1076 // may not be dead if the replacement process recursively simplified to
1077 // something else needing this node.
1078 if (N->use_empty()) {
1079 // Nodes can be reintroduced into the worklist. Make sure we do not
1080 // process a node that has been replaced.
1081 removeFromWorkList(N);
Scott Michelfdc40a02009-02-17 22:15:04 +00001082
Dan Gohmandbe664a2009-01-19 21:44:21 +00001083 // Finally, since the node is now dead, remove it from the graph.
1084 DAG.DeleteNode(N);
1085 }
Evan Cheng17a568b2008-08-29 22:21:44 +00001086 }
Scott Michelfdc40a02009-02-17 22:15:04 +00001087
Chris Lattner95038592005-10-05 06:35:28 +00001088 // If the root changed (e.g. it was a dead load, update the root).
1089 DAG.setRoot(Dummy.getValue());
Hal Finkel31490ba2012-04-16 03:33:22 +00001090 DAG.RemoveDeadNodes();
Nate Begeman1d4d4142005-09-01 00:19:25 +00001091}
1092
Dan Gohman475871a2008-07-27 21:46:04 +00001093SDValue DAGCombiner::visit(SDNode *N) {
Evan Chengb3a3d5e2010-04-28 07:10:39 +00001094 switch (N->getOpcode()) {
Nate Begeman1d4d4142005-09-01 00:19:25 +00001095 default: break;
Nate Begeman4942a962005-09-01 00:33:32 +00001096 case ISD::TokenFactor: return visitTokenFactor(N);
Chris Lattnerfec42eb2008-02-13 07:25:05 +00001097 case ISD::MERGE_VALUES: return visitMERGE_VALUES(N);
Nate Begeman646d7e22005-09-02 21:18:40 +00001098 case ISD::ADD: return visitADD(N);
1099 case ISD::SUB: return visitSUB(N);
Chris Lattner91153682007-03-04 20:03:15 +00001100 case ISD::ADDC: return visitADDC(N);
Craig Toppercc274522012-01-07 09:06:39 +00001101 case ISD::SUBC: return visitSUBC(N);
Chris Lattner91153682007-03-04 20:03:15 +00001102 case ISD::ADDE: return visitADDE(N);
Craig Toppercc274522012-01-07 09:06:39 +00001103 case ISD::SUBE: return visitSUBE(N);
Nate Begeman646d7e22005-09-02 21:18:40 +00001104 case ISD::MUL: return visitMUL(N);
1105 case ISD::SDIV: return visitSDIV(N);
1106 case ISD::UDIV: return visitUDIV(N);
1107 case ISD::SREM: return visitSREM(N);
1108 case ISD::UREM: return visitUREM(N);
1109 case ISD::MULHU: return visitMULHU(N);
1110 case ISD::MULHS: return visitMULHS(N);
Dan Gohman389079b2007-10-08 17:57:15 +00001111 case ISD::SMUL_LOHI: return visitSMUL_LOHI(N);
1112 case ISD::UMUL_LOHI: return visitUMUL_LOHI(N);
Benjamin Kramerf55d26e2011-05-21 18:31:55 +00001113 case ISD::SMULO: return visitSMULO(N);
1114 case ISD::UMULO: return visitUMULO(N);
Dan Gohman389079b2007-10-08 17:57:15 +00001115 case ISD::SDIVREM: return visitSDIVREM(N);
1116 case ISD::UDIVREM: return visitUDIVREM(N);
Nate Begeman646d7e22005-09-02 21:18:40 +00001117 case ISD::AND: return visitAND(N);
1118 case ISD::OR: return visitOR(N);
1119 case ISD::XOR: return visitXOR(N);
1120 case ISD::SHL: return visitSHL(N);
1121 case ISD::SRA: return visitSRA(N);
1122 case ISD::SRL: return visitSRL(N);
1123 case ISD::CTLZ: return visitCTLZ(N);
Chandler Carruth63974b22011-12-13 01:56:10 +00001124 case ISD::CTLZ_ZERO_UNDEF: return visitCTLZ_ZERO_UNDEF(N);
Nate Begeman646d7e22005-09-02 21:18:40 +00001125 case ISD::CTTZ: return visitCTTZ(N);
Chandler Carruth63974b22011-12-13 01:56:10 +00001126 case ISD::CTTZ_ZERO_UNDEF: return visitCTTZ_ZERO_UNDEF(N);
Nate Begeman646d7e22005-09-02 21:18:40 +00001127 case ISD::CTPOP: return visitCTPOP(N);
Nate Begeman452d7beb2005-09-16 00:54:12 +00001128 case ISD::SELECT: return visitSELECT(N);
1129 case ISD::SELECT_CC: return visitSELECT_CC(N);
1130 case ISD::SETCC: return visitSETCC(N);
Nate Begeman646d7e22005-09-02 21:18:40 +00001131 case ISD::SIGN_EXTEND: return visitSIGN_EXTEND(N);
1132 case ISD::ZERO_EXTEND: return visitZERO_EXTEND(N);
Chris Lattner5ffc0662006-05-05 05:58:59 +00001133 case ISD::ANY_EXTEND: return visitANY_EXTEND(N);
Nate Begeman646d7e22005-09-02 21:18:40 +00001134 case ISD::SIGN_EXTEND_INREG: return visitSIGN_EXTEND_INREG(N);
1135 case ISD::TRUNCATE: return visitTRUNCATE(N);
Wesley Peckbf17cfa2010-11-23 03:31:01 +00001136 case ISD::BITCAST: return visitBITCAST(N);
Evan Cheng9bfa03c2008-05-12 23:04:07 +00001137 case ISD::BUILD_PAIR: return visitBUILD_PAIR(N);
Chris Lattner01b3d732005-09-28 22:28:18 +00001138 case ISD::FADD: return visitFADD(N);
1139 case ISD::FSUB: return visitFSUB(N);
1140 case ISD::FMUL: return visitFMUL(N);
Owen Anderson062c0a52012-05-02 22:17:40 +00001141 case ISD::FMA: return visitFMA(N);
Chris Lattner01b3d732005-09-28 22:28:18 +00001142 case ISD::FDIV: return visitFDIV(N);
1143 case ISD::FREM: return visitFREM(N);
Chris Lattner12d83032006-03-05 05:30:57 +00001144 case ISD::FCOPYSIGN: return visitFCOPYSIGN(N);
Nate Begeman646d7e22005-09-02 21:18:40 +00001145 case ISD::SINT_TO_FP: return visitSINT_TO_FP(N);
1146 case ISD::UINT_TO_FP: return visitUINT_TO_FP(N);
1147 case ISD::FP_TO_SINT: return visitFP_TO_SINT(N);
1148 case ISD::FP_TO_UINT: return visitFP_TO_UINT(N);
1149 case ISD::FP_ROUND: return visitFP_ROUND(N);
1150 case ISD::FP_ROUND_INREG: return visitFP_ROUND_INREG(N);
1151 case ISD::FP_EXTEND: return visitFP_EXTEND(N);
1152 case ISD::FNEG: return visitFNEG(N);
1153 case ISD::FABS: return visitFABS(N);
Owen Anderson7c626d32012-08-13 23:32:49 +00001154 case ISD::FFLOOR: return visitFFLOOR(N);
1155 case ISD::FCEIL: return visitFCEIL(N);
1156 case ISD::FTRUNC: return visitFTRUNC(N);
Nate Begeman44728a72005-09-19 22:34:01 +00001157 case ISD::BRCOND: return visitBRCOND(N);
Nate Begeman44728a72005-09-19 22:34:01 +00001158 case ISD::BR_CC: return visitBR_CC(N);
Chris Lattner01a22022005-10-10 22:04:48 +00001159 case ISD::LOAD: return visitLOAD(N);
Chris Lattner87514ca2005-10-10 22:31:19 +00001160 case ISD::STORE: return visitSTORE(N);
Chris Lattnerca242442006-03-19 01:27:56 +00001161 case ISD::INSERT_VECTOR_ELT: return visitINSERT_VECTOR_ELT(N);
Evan Cheng513da432007-10-06 08:19:55 +00001162 case ISD::EXTRACT_VECTOR_ELT: return visitEXTRACT_VECTOR_ELT(N);
Dan Gohman7f321562007-06-25 16:23:39 +00001163 case ISD::BUILD_VECTOR: return visitBUILD_VECTOR(N);
1164 case ISD::CONCAT_VECTORS: return visitCONCAT_VECTORS(N);
Bruno Cardoso Lopese97190f2011-09-20 23:19:33 +00001165 case ISD::EXTRACT_SUBVECTOR: return visitEXTRACT_SUBVECTOR(N);
Chris Lattner66445d32006-03-28 22:11:53 +00001166 case ISD::VECTOR_SHUFFLE: return visitVECTOR_SHUFFLE(N);
Jim Grosbach9a526492010-06-23 16:07:42 +00001167 case ISD::MEMBARRIER: return visitMEMBARRIER(N);
Nate Begeman1d4d4142005-09-01 00:19:25 +00001168 }
Dan Gohman475871a2008-07-27 21:46:04 +00001169 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00001170}
1171
Dan Gohman475871a2008-07-27 21:46:04 +00001172SDValue DAGCombiner::combine(SDNode *N) {
Dan Gohman475871a2008-07-27 21:46:04 +00001173 SDValue RV = visit(N);
Dan Gohman389079b2007-10-08 17:57:15 +00001174
1175 // If nothing happened, try a target-specific DAG combine.
Gabor Greifba36cb52008-08-28 21:40:38 +00001176 if (RV.getNode() == 0) {
Dan Gohman389079b2007-10-08 17:57:15 +00001177 assert(N->getOpcode() != ISD::DELETED_NODE &&
1178 "Node was deleted but visit returned NULL!");
1179
1180 if (N->getOpcode() >= ISD::BUILTIN_OP_END ||
1181 TLI.hasTargetDAGCombine((ISD::NodeType)N->getOpcode())) {
1182
1183 // Expose the DAG combiner to the target combiner impls.
Scott Michelfdc40a02009-02-17 22:15:04 +00001184 TargetLowering::DAGCombinerInfo
Jakob Stoklund Olesen78d12642009-07-24 18:22:59 +00001185 DagCombineInfo(DAG, !LegalTypes, !LegalOperations, false, this);
Dan Gohman389079b2007-10-08 17:57:15 +00001186
1187 RV = TLI.PerformDAGCombine(N, DagCombineInfo);
1188 }
1189 }
1190
Evan Chengb3a3d5e2010-04-28 07:10:39 +00001191 // If nothing happened still, try promoting the operation.
1192 if (RV.getNode() == 0) {
1193 switch (N->getOpcode()) {
1194 default: break;
1195 case ISD::ADD:
1196 case ISD::SUB:
1197 case ISD::MUL:
1198 case ISD::AND:
1199 case ISD::OR:
1200 case ISD::XOR:
1201 RV = PromoteIntBinOp(SDValue(N, 0));
1202 break;
1203 case ISD::SHL:
1204 case ISD::SRA:
1205 case ISD::SRL:
1206 RV = PromoteIntShiftOp(SDValue(N, 0));
1207 break;
1208 case ISD::SIGN_EXTEND:
1209 case ISD::ZERO_EXTEND:
1210 case ISD::ANY_EXTEND:
1211 RV = PromoteExtend(SDValue(N, 0));
1212 break;
1213 case ISD::LOAD:
1214 if (PromoteLoad(SDValue(N, 0)))
1215 RV = SDValue(N, 0);
1216 break;
1217 }
1218 }
1219
Scott Michelfdc40a02009-02-17 22:15:04 +00001220 // If N is a commutative binary node, try commuting it to enable more
Evan Cheng08b11732008-03-22 01:55:50 +00001221 // sdisel CSE.
Scott Michelfdc40a02009-02-17 22:15:04 +00001222 if (RV.getNode() == 0 &&
Evan Cheng08b11732008-03-22 01:55:50 +00001223 SelectionDAG::isCommutativeBinOp(N->getOpcode()) &&
1224 N->getNumValues() == 1) {
Dan Gohman475871a2008-07-27 21:46:04 +00001225 SDValue N0 = N->getOperand(0);
1226 SDValue N1 = N->getOperand(1);
Bill Wendling5c71acf2009-01-30 01:13:16 +00001227
Evan Cheng08b11732008-03-22 01:55:50 +00001228 // Constant operands are canonicalized to RHS.
1229 if (isa<ConstantSDNode>(N0) || !isa<ConstantSDNode>(N1)) {
Dan Gohman475871a2008-07-27 21:46:04 +00001230 SDValue Ops[] = { N1, N0 };
Evan Cheng08b11732008-03-22 01:55:50 +00001231 SDNode *CSENode = DAG.getNodeIfExists(N->getOpcode(), N->getVTList(),
1232 Ops, 2);
Evan Chengea100462008-03-24 23:55:16 +00001233 if (CSENode)
Dan Gohman475871a2008-07-27 21:46:04 +00001234 return SDValue(CSENode, 0);
Evan Cheng08b11732008-03-22 01:55:50 +00001235 }
1236 }
1237
Dan Gohman389079b2007-10-08 17:57:15 +00001238 return RV;
Scott Michelfdc40a02009-02-17 22:15:04 +00001239}
Dan Gohman389079b2007-10-08 17:57:15 +00001240
Chris Lattner6270f682006-10-08 22:57:01 +00001241/// getInputChainForNode - Given a node, return its input chain if it has one,
1242/// otherwise return a null sd operand.
Dan Gohman475871a2008-07-27 21:46:04 +00001243static SDValue getInputChainForNode(SDNode *N) {
Chris Lattner6270f682006-10-08 22:57:01 +00001244 if (unsigned NumOps = N->getNumOperands()) {
Owen Anderson825b72b2009-08-11 20:47:22 +00001245 if (N->getOperand(0).getValueType() == MVT::Other)
Chris Lattner6270f682006-10-08 22:57:01 +00001246 return N->getOperand(0);
Owen Anderson825b72b2009-08-11 20:47:22 +00001247 else if (N->getOperand(NumOps-1).getValueType() == MVT::Other)
Chris Lattner6270f682006-10-08 22:57:01 +00001248 return N->getOperand(NumOps-1);
1249 for (unsigned i = 1; i < NumOps-1; ++i)
Owen Anderson825b72b2009-08-11 20:47:22 +00001250 if (N->getOperand(i).getValueType() == MVT::Other)
Chris Lattner6270f682006-10-08 22:57:01 +00001251 return N->getOperand(i);
1252 }
Bill Wendling5c71acf2009-01-30 01:13:16 +00001253 return SDValue();
Chris Lattner6270f682006-10-08 22:57:01 +00001254}
1255
Dan Gohman475871a2008-07-27 21:46:04 +00001256SDValue DAGCombiner::visitTokenFactor(SDNode *N) {
Chris Lattner6270f682006-10-08 22:57:01 +00001257 // If N has two operands, where one has an input chain equal to the other,
1258 // the 'other' chain is redundant.
1259 if (N->getNumOperands() == 2) {
Gabor Greifba36cb52008-08-28 21:40:38 +00001260 if (getInputChainForNode(N->getOperand(0).getNode()) == N->getOperand(1))
Chris Lattner6270f682006-10-08 22:57:01 +00001261 return N->getOperand(0);
Gabor Greifba36cb52008-08-28 21:40:38 +00001262 if (getInputChainForNode(N->getOperand(1).getNode()) == N->getOperand(0))
Chris Lattner6270f682006-10-08 22:57:01 +00001263 return N->getOperand(1);
1264 }
Scott Michelfdc40a02009-02-17 22:15:04 +00001265
Chris Lattnerc76d4412007-05-16 06:37:59 +00001266 SmallVector<SDNode *, 8> TFs; // List of token factors to visit.
Dan Gohman475871a2008-07-27 21:46:04 +00001267 SmallVector<SDValue, 8> Ops; // Ops for replacing token factor.
Scott Michelfdc40a02009-02-17 22:15:04 +00001268 SmallPtrSet<SDNode*, 16> SeenOps;
Chris Lattnerc76d4412007-05-16 06:37:59 +00001269 bool Changed = false; // If we should replace this token factor.
Scott Michelfdc40a02009-02-17 22:15:04 +00001270
Jim Laskey6ff23e52006-10-04 16:53:27 +00001271 // Start out with this token factor.
Jim Laskey279f0532006-09-25 16:29:54 +00001272 TFs.push_back(N);
Scott Michelfdc40a02009-02-17 22:15:04 +00001273
Jim Laskey71382342006-10-07 23:37:56 +00001274 // Iterate through token factors. The TFs grows when new token factors are
Jim Laskeybc588b82006-10-05 15:07:25 +00001275 // encountered.
1276 for (unsigned i = 0; i < TFs.size(); ++i) {
1277 SDNode *TF = TFs[i];
Scott Michelfdc40a02009-02-17 22:15:04 +00001278
Jim Laskey6ff23e52006-10-04 16:53:27 +00001279 // Check each of the operands.
1280 for (unsigned i = 0, ie = TF->getNumOperands(); i != ie; ++i) {
Dan Gohman475871a2008-07-27 21:46:04 +00001281 SDValue Op = TF->getOperand(i);
Scott Michelfdc40a02009-02-17 22:15:04 +00001282
Jim Laskey6ff23e52006-10-04 16:53:27 +00001283 switch (Op.getOpcode()) {
1284 case ISD::EntryToken:
Jim Laskeybc588b82006-10-05 15:07:25 +00001285 // Entry tokens don't need to be added to the list. They are
1286 // rededundant.
1287 Changed = true;
Jim Laskey6ff23e52006-10-04 16:53:27 +00001288 break;
Scott Michelfdc40a02009-02-17 22:15:04 +00001289
Jim Laskey6ff23e52006-10-04 16:53:27 +00001290 case ISD::TokenFactor:
Nate Begemanb6aef5c2009-09-15 00:18:30 +00001291 if (Op.hasOneUse() &&
Gabor Greifba36cb52008-08-28 21:40:38 +00001292 std::find(TFs.begin(), TFs.end(), Op.getNode()) == TFs.end()) {
Jim Laskey6ff23e52006-10-04 16:53:27 +00001293 // Queue up for processing.
Gabor Greifba36cb52008-08-28 21:40:38 +00001294 TFs.push_back(Op.getNode());
Jim Laskey6ff23e52006-10-04 16:53:27 +00001295 // Clean up in case the token factor is removed.
Gabor Greifba36cb52008-08-28 21:40:38 +00001296 AddToWorkList(Op.getNode());
Jim Laskey6ff23e52006-10-04 16:53:27 +00001297 Changed = true;
1298 break;
Jim Laskey279f0532006-09-25 16:29:54 +00001299 }
Jim Laskey6ff23e52006-10-04 16:53:27 +00001300 // Fall thru
Scott Michelfdc40a02009-02-17 22:15:04 +00001301
Jim Laskey6ff23e52006-10-04 16:53:27 +00001302 default:
Chris Lattnerc76d4412007-05-16 06:37:59 +00001303 // Only add if it isn't already in the list.
Gabor Greifba36cb52008-08-28 21:40:38 +00001304 if (SeenOps.insert(Op.getNode()))
Jim Laskeybc588b82006-10-05 15:07:25 +00001305 Ops.push_back(Op);
Chris Lattnerc76d4412007-05-16 06:37:59 +00001306 else
1307 Changed = true;
Jim Laskey6ff23e52006-10-04 16:53:27 +00001308 break;
Jim Laskey279f0532006-09-25 16:29:54 +00001309 }
1310 }
Jim Laskey6ff23e52006-10-04 16:53:27 +00001311 }
Wesley Peckbf17cfa2010-11-23 03:31:01 +00001312
Dan Gohman475871a2008-07-27 21:46:04 +00001313 SDValue Result;
Jim Laskey6ff23e52006-10-04 16:53:27 +00001314
1315 // If we've change things around then replace token factor.
1316 if (Changed) {
Dan Gohman30359592008-01-29 13:02:09 +00001317 if (Ops.empty()) {
Jim Laskey6ff23e52006-10-04 16:53:27 +00001318 // The entry token is the only possible outcome.
1319 Result = DAG.getEntryNode();
1320 } else {
1321 // New and improved token factor.
Bill Wendling5c71acf2009-01-30 01:13:16 +00001322 Result = DAG.getNode(ISD::TokenFactor, N->getDebugLoc(),
Owen Anderson825b72b2009-08-11 20:47:22 +00001323 MVT::Other, &Ops[0], Ops.size());
Nate Begemanded49632005-10-13 03:11:28 +00001324 }
Bill Wendling5c71acf2009-01-30 01:13:16 +00001325
Jim Laskey274062c2006-10-13 23:32:28 +00001326 // Don't add users to work list.
1327 return CombineTo(N, Result, false);
Nate Begemanded49632005-10-13 03:11:28 +00001328 }
Scott Michelfdc40a02009-02-17 22:15:04 +00001329
Jim Laskey6ff23e52006-10-04 16:53:27 +00001330 return Result;
Nate Begeman1d4d4142005-09-01 00:19:25 +00001331}
1332
Chris Lattnerfec42eb2008-02-13 07:25:05 +00001333/// MERGE_VALUES can always be eliminated.
Dan Gohman475871a2008-07-27 21:46:04 +00001334SDValue DAGCombiner::visitMERGE_VALUES(SDNode *N) {
Chris Lattnerfec42eb2008-02-13 07:25:05 +00001335 WorkListRemover DeadNodes(*this);
Dan Gohman00edf392009-08-10 23:43:19 +00001336 // Replacing results may cause a different MERGE_VALUES to suddenly
1337 // be CSE'd with N, and carry its uses with it. Iterate until no
1338 // uses remain, to ensure that the node can be safely deleted.
Pete Cooper3affd9e2012-06-20 19:35:43 +00001339 // First add the users of this node to the work list so that they
1340 // can be tried again once they have new operands.
1341 AddUsersToWorkList(N);
Dan Gohman00edf392009-08-10 23:43:19 +00001342 do {
1343 for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i)
Jakob Stoklund Olesenbc7d4482012-04-20 22:08:46 +00001344 DAG.ReplaceAllUsesOfValueWith(SDValue(N, i), N->getOperand(i));
Dan Gohman00edf392009-08-10 23:43:19 +00001345 } while (!N->use_empty());
Chris Lattnerfec42eb2008-02-13 07:25:05 +00001346 removeFromWorkList(N);
1347 DAG.DeleteNode(N);
Dan Gohman475871a2008-07-27 21:46:04 +00001348 return SDValue(N, 0); // Return N so it doesn't get rechecked!
Chris Lattnerfec42eb2008-02-13 07:25:05 +00001349}
1350
Evan Cheng42d7ccf2007-01-19 17:51:44 +00001351static
Bill Wendlingd69c3142009-01-30 02:23:43 +00001352SDValue combineShlAddConstant(DebugLoc DL, SDValue N0, SDValue N1,
1353 SelectionDAG &DAG) {
Owen Andersone50ed302009-08-10 22:56:29 +00001354 EVT VT = N0.getValueType();
Dan Gohman475871a2008-07-27 21:46:04 +00001355 SDValue N00 = N0.getOperand(0);
1356 SDValue N01 = N0.getOperand(1);
Evan Cheng42d7ccf2007-01-19 17:51:44 +00001357 ConstantSDNode *N01C = dyn_cast<ConstantSDNode>(N01);
Bill Wendlingd69c3142009-01-30 02:23:43 +00001358
Gabor Greifba36cb52008-08-28 21:40:38 +00001359 if (N01C && N00.getOpcode() == ISD::ADD && N00.getNode()->hasOneUse() &&
Evan Cheng42d7ccf2007-01-19 17:51:44 +00001360 isa<ConstantSDNode>(N00.getOperand(1))) {
Bill Wendlingd69c3142009-01-30 02:23:43 +00001361 // fold (add (shl (add x, c1), c2), ) -> (add (add (shl x, c2), c1<<c2), )
1362 N0 = DAG.getNode(ISD::ADD, N0.getDebugLoc(), VT,
1363 DAG.getNode(ISD::SHL, N00.getDebugLoc(), VT,
1364 N00.getOperand(0), N01),
1365 DAG.getNode(ISD::SHL, N01.getDebugLoc(), VT,
1366 N00.getOperand(1), N01));
1367 return DAG.getNode(ISD::ADD, DL, VT, N0, N1);
Evan Cheng42d7ccf2007-01-19 17:51:44 +00001368 }
Bill Wendlingd69c3142009-01-30 02:23:43 +00001369
Dan Gohman475871a2008-07-27 21:46:04 +00001370 return SDValue();
Evan Cheng42d7ccf2007-01-19 17:51:44 +00001371}
1372
Dan Gohman475871a2008-07-27 21:46:04 +00001373SDValue DAGCombiner::visitADD(SDNode *N) {
1374 SDValue N0 = N->getOperand(0);
1375 SDValue N1 = N->getOperand(1);
Nate Begeman646d7e22005-09-02 21:18:40 +00001376 ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0);
1377 ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1);
Owen Andersone50ed302009-08-10 22:56:29 +00001378 EVT VT = N0.getValueType();
Dan Gohman7f321562007-06-25 16:23:39 +00001379
1380 // fold vector ops
Duncan Sands83ec4b62008-06-06 12:08:01 +00001381 if (VT.isVector()) {
Dan Gohman475871a2008-07-27 21:46:04 +00001382 SDValue FoldedVOp = SimplifyVBinOp(N);
Gabor Greifba36cb52008-08-28 21:40:38 +00001383 if (FoldedVOp.getNode()) return FoldedVOp;
Craig Topper48b509c2012-12-10 08:12:29 +00001384
1385 // fold (add x, 0) -> x, vector edition
1386 if (ISD::isBuildVectorAllZeros(N1.getNode()))
1387 return N0;
1388 if (ISD::isBuildVectorAllZeros(N0.getNode()))
1389 return N1;
Dan Gohman05d92fe2007-07-13 20:03:40 +00001390 }
Bill Wendling2476e5d2008-12-10 22:36:00 +00001391
Dan Gohman613e0d82007-07-03 14:03:57 +00001392 // fold (add x, undef) -> undef
Dan Gohman70fb1ae2007-07-10 15:19:29 +00001393 if (N0.getOpcode() == ISD::UNDEF)
1394 return N0;
1395 if (N1.getOpcode() == ISD::UNDEF)
Dan Gohman613e0d82007-07-03 14:03:57 +00001396 return N1;
Nate Begeman1d4d4142005-09-01 00:19:25 +00001397 // fold (add c1, c2) -> c1+c2
Nate Begeman646d7e22005-09-02 21:18:40 +00001398 if (N0C && N1C)
Bill Wendlingf3cbca22008-09-24 10:25:02 +00001399 return DAG.FoldConstantArithmetic(ISD::ADD, VT, N0C, N1C);
Nate Begeman99801192005-09-07 23:25:52 +00001400 // canonicalize constant to RHS
Nate Begemana0e221d2005-10-18 00:28:13 +00001401 if (N0C && !N1C)
Bill Wendlingf4eb2262009-01-30 02:31:17 +00001402 return DAG.getNode(ISD::ADD, N->getDebugLoc(), VT, N1, N0);
Nate Begeman1d4d4142005-09-01 00:19:25 +00001403 // fold (add x, 0) -> x
Nate Begeman646d7e22005-09-02 21:18:40 +00001404 if (N1C && N1C->isNullValue())
Nate Begeman83e75ec2005-09-06 04:43:02 +00001405 return N0;
Dan Gohman6520e202008-10-18 02:06:02 +00001406 // fold (add Sym, c) -> Sym+c
1407 if (GlobalAddressSDNode *GA = dyn_cast<GlobalAddressSDNode>(N0))
Duncan Sands25cf2272008-11-24 14:53:14 +00001408 if (!LegalOperations && TLI.isOffsetFoldingLegal(GA) && N1C &&
Dan Gohman6520e202008-10-18 02:06:02 +00001409 GA->getOpcode() == ISD::GlobalAddress)
Devang Patel0d881da2010-07-06 22:08:15 +00001410 return DAG.getGlobalAddress(GA->getGlobal(), N1C->getDebugLoc(), VT,
Dan Gohman6520e202008-10-18 02:06:02 +00001411 GA->getOffset() +
1412 (uint64_t)N1C->getSExtValue());
Chris Lattner4aafb4f2006-01-12 20:22:43 +00001413 // fold ((c1-A)+c2) -> (c1+c2)-A
1414 if (N1C && N0.getOpcode() == ISD::SUB)
1415 if (ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0.getOperand(0)))
Bill Wendlingf4eb2262009-01-30 02:31:17 +00001416 return DAG.getNode(ISD::SUB, N->getDebugLoc(), VT,
Dan Gohman002e5d02008-03-13 22:13:53 +00001417 DAG.getConstant(N1C->getAPIntValue()+
1418 N0C->getAPIntValue(), VT),
Chris Lattner4aafb4f2006-01-12 20:22:43 +00001419 N0.getOperand(1));
Nate Begemancd4d58c2006-02-03 06:46:56 +00001420 // reassociate add
Bill Wendling35247c32009-01-30 00:45:56 +00001421 SDValue RADD = ReassociateOps(ISD::ADD, N->getDebugLoc(), N0, N1);
Gabor Greifba36cb52008-08-28 21:40:38 +00001422 if (RADD.getNode() != 0)
Nate Begemancd4d58c2006-02-03 06:46:56 +00001423 return RADD;
Nate Begeman1d4d4142005-09-01 00:19:25 +00001424 // fold ((0-A) + B) -> B-A
1425 if (N0.getOpcode() == ISD::SUB && isa<ConstantSDNode>(N0.getOperand(0)) &&
1426 cast<ConstantSDNode>(N0.getOperand(0))->isNullValue())
Bill Wendlingf4eb2262009-01-30 02:31:17 +00001427 return DAG.getNode(ISD::SUB, N->getDebugLoc(), VT, N1, N0.getOperand(1));
Nate Begeman1d4d4142005-09-01 00:19:25 +00001428 // fold (A + (0-B)) -> A-B
1429 if (N1.getOpcode() == ISD::SUB && isa<ConstantSDNode>(N1.getOperand(0)) &&
1430 cast<ConstantSDNode>(N1.getOperand(0))->isNullValue())
Bill Wendlingf4eb2262009-01-30 02:31:17 +00001431 return DAG.getNode(ISD::SUB, N->getDebugLoc(), VT, N0, N1.getOperand(1));
Chris Lattner01b3d732005-09-28 22:28:18 +00001432 // fold (A+(B-A)) -> B
1433 if (N1.getOpcode() == ISD::SUB && N0 == N1.getOperand(1))
Nate Begeman83e75ec2005-09-06 04:43:02 +00001434 return N1.getOperand(0);
Dale Johannesen56eca912008-11-27 00:43:21 +00001435 // fold ((B-A)+A) -> B
1436 if (N0.getOpcode() == ISD::SUB && N1 == N0.getOperand(1))
1437 return N0.getOperand(0);
Dale Johannesen221cd2f2008-12-02 01:30:54 +00001438 // fold (A+(B-(A+C))) to (B-C)
1439 if (N1.getOpcode() == ISD::SUB && N1.getOperand(1).getOpcode() == ISD::ADD &&
Bill Wendlingf4eb2262009-01-30 02:31:17 +00001440 N0 == N1.getOperand(1).getOperand(0))
1441 return DAG.getNode(ISD::SUB, N->getDebugLoc(), VT, N1.getOperand(0),
Dale Johannesen221cd2f2008-12-02 01:30:54 +00001442 N1.getOperand(1).getOperand(1));
Dale Johannesen221cd2f2008-12-02 01:30:54 +00001443 // fold (A+(B-(C+A))) to (B-C)
1444 if (N1.getOpcode() == ISD::SUB && N1.getOperand(1).getOpcode() == ISD::ADD &&
Bill Wendlingf4eb2262009-01-30 02:31:17 +00001445 N0 == N1.getOperand(1).getOperand(1))
1446 return DAG.getNode(ISD::SUB, N->getDebugLoc(), VT, N1.getOperand(0),
Dale Johannesen221cd2f2008-12-02 01:30:54 +00001447 N1.getOperand(1).getOperand(0));
Dale Johannesen7c7bc722008-12-23 23:47:22 +00001448 // fold (A+((B-A)+or-C)) to (B+or-C)
Dale Johannesen34d79852008-12-02 18:40:40 +00001449 if ((N1.getOpcode() == ISD::SUB || N1.getOpcode() == ISD::ADD) &&
1450 N1.getOperand(0).getOpcode() == ISD::SUB &&
Bill Wendlingf4eb2262009-01-30 02:31:17 +00001451 N0 == N1.getOperand(0).getOperand(1))
1452 return DAG.getNode(N1.getOpcode(), N->getDebugLoc(), VT,
1453 N1.getOperand(0).getOperand(0), N1.getOperand(1));
Dale Johannesen34d79852008-12-02 18:40:40 +00001454
Dale Johannesen221cd2f2008-12-02 01:30:54 +00001455 // fold (A-B)+(C-D) to (A+C)-(B+D) when A or C is constant
1456 if (N0.getOpcode() == ISD::SUB && N1.getOpcode() == ISD::SUB) {
1457 SDValue N00 = N0.getOperand(0);
1458 SDValue N01 = N0.getOperand(1);
1459 SDValue N10 = N1.getOperand(0);
1460 SDValue N11 = N1.getOperand(1);
Bill Wendlingf4eb2262009-01-30 02:31:17 +00001461
1462 if (isa<ConstantSDNode>(N00) || isa<ConstantSDNode>(N10))
1463 return DAG.getNode(ISD::SUB, N->getDebugLoc(), VT,
1464 DAG.getNode(ISD::ADD, N0.getDebugLoc(), VT, N00, N10),
1465 DAG.getNode(ISD::ADD, N1.getDebugLoc(), VT, N01, N11));
Dale Johannesen221cd2f2008-12-02 01:30:54 +00001466 }
Chris Lattner947c2892006-03-13 06:51:27 +00001467
Dan Gohman475871a2008-07-27 21:46:04 +00001468 if (!VT.isVector() && SimplifyDemandedBits(SDValue(N, 0)))
1469 return SDValue(N, 0);
Scott Michelfdc40a02009-02-17 22:15:04 +00001470
Sylvestre Ledru94c22712012-09-27 10:14:43 +00001471 // fold (a+b) -> (a|b) iff a and b share no bits.
Duncan Sands83ec4b62008-06-06 12:08:01 +00001472 if (VT.isInteger() && !VT.isVector()) {
Dan Gohman948d8ea2008-02-20 16:33:30 +00001473 APInt LHSZero, LHSOne;
1474 APInt RHSZero, RHSOne;
Rafael Espindola26c8dcc2012-04-04 12:51:34 +00001475 DAG.ComputeMaskedBits(N0, LHSZero, LHSOne);
Bill Wendlingf4eb2262009-01-30 02:31:17 +00001476
Dan Gohman948d8ea2008-02-20 16:33:30 +00001477 if (LHSZero.getBoolValue()) {
Rafael Espindola26c8dcc2012-04-04 12:51:34 +00001478 DAG.ComputeMaskedBits(N1, RHSZero, RHSOne);
Scott Michelfdc40a02009-02-17 22:15:04 +00001479
Chris Lattner947c2892006-03-13 06:51:27 +00001480 // If all possibly-set bits on the LHS are clear on the RHS, return an OR.
1481 // If all possibly-set bits on the RHS are clear on the LHS, return an OR.
Rafael Espindola26c8dcc2012-04-04 12:51:34 +00001482 if ((RHSZero & ~LHSZero) == ~LHSZero || (LHSZero & ~RHSZero) == ~RHSZero)
Bill Wendlingf4eb2262009-01-30 02:31:17 +00001483 return DAG.getNode(ISD::OR, N->getDebugLoc(), VT, N0, N1);
Chris Lattner947c2892006-03-13 06:51:27 +00001484 }
1485 }
Evan Cheng3ef554d2006-11-06 08:14:30 +00001486
Evan Cheng42d7ccf2007-01-19 17:51:44 +00001487 // fold (add (shl (add x, c1), c2), ) -> (add (add (shl x, c2), c1<<c2), )
Gabor Greifba36cb52008-08-28 21:40:38 +00001488 if (N0.getOpcode() == ISD::SHL && N0.getNode()->hasOneUse()) {
Bill Wendlingd69c3142009-01-30 02:23:43 +00001489 SDValue Result = combineShlAddConstant(N->getDebugLoc(), N0, N1, DAG);
Gabor Greifba36cb52008-08-28 21:40:38 +00001490 if (Result.getNode()) return Result;
Evan Cheng42d7ccf2007-01-19 17:51:44 +00001491 }
Gabor Greifba36cb52008-08-28 21:40:38 +00001492 if (N1.getOpcode() == ISD::SHL && N1.getNode()->hasOneUse()) {
Bill Wendlingd69c3142009-01-30 02:23:43 +00001493 SDValue Result = combineShlAddConstant(N->getDebugLoc(), N1, N0, DAG);
Gabor Greifba36cb52008-08-28 21:40:38 +00001494 if (Result.getNode()) return Result;
Evan Cheng42d7ccf2007-01-19 17:51:44 +00001495 }
1496
Dan Gohmancd9e1552010-01-19 23:30:49 +00001497 // fold (add x, shl(0 - y, n)) -> sub(x, shl(y, n))
1498 if (N1.getOpcode() == ISD::SHL &&
1499 N1.getOperand(0).getOpcode() == ISD::SUB)
1500 if (ConstantSDNode *C =
1501 dyn_cast<ConstantSDNode>(N1.getOperand(0).getOperand(0)))
1502 if (C->getAPIntValue() == 0)
1503 return DAG.getNode(ISD::SUB, N->getDebugLoc(), VT, N0,
1504 DAG.getNode(ISD::SHL, N->getDebugLoc(), VT,
1505 N1.getOperand(0).getOperand(1),
1506 N1.getOperand(1)));
1507 if (N0.getOpcode() == ISD::SHL &&
1508 N0.getOperand(0).getOpcode() == ISD::SUB)
1509 if (ConstantSDNode *C =
1510 dyn_cast<ConstantSDNode>(N0.getOperand(0).getOperand(0)))
1511 if (C->getAPIntValue() == 0)
1512 return DAG.getNode(ISD::SUB, N->getDebugLoc(), VT, N1,
1513 DAG.getNode(ISD::SHL, N->getDebugLoc(), VT,
1514 N0.getOperand(0).getOperand(1),
1515 N0.getOperand(1)));
1516
Owen Andersonbc146b02010-09-21 20:42:50 +00001517 if (N1.getOpcode() == ISD::AND) {
1518 SDValue AndOp0 = N1.getOperand(0);
Wesley Peckbf17cfa2010-11-23 03:31:01 +00001519 ConstantSDNode *AndOp1 = dyn_cast<ConstantSDNode>(N1->getOperand(1));
Owen Andersonbc146b02010-09-21 20:42:50 +00001520 unsigned NumSignBits = DAG.ComputeNumSignBits(AndOp0);
1521 unsigned DestBits = VT.getScalarType().getSizeInBits();
Wesley Peckbf17cfa2010-11-23 03:31:01 +00001522
Owen Andersonbc146b02010-09-21 20:42:50 +00001523 // (add z, (and (sbbl x, x), 1)) -> (sub z, (sbbl x, x))
1524 // and similar xforms where the inner op is either ~0 or 0.
1525 if (NumSignBits == DestBits && AndOp1 && AndOp1->isOne()) {
1526 DebugLoc DL = N->getDebugLoc();
1527 return DAG.getNode(ISD::SUB, DL, VT, N->getOperand(0), AndOp0);
1528 }
1529 }
1530
Benjamin Kramerf50125e2010-12-22 23:17:45 +00001531 // add (sext i1), X -> sub X, (zext i1)
1532 if (N0.getOpcode() == ISD::SIGN_EXTEND &&
1533 N0.getOperand(0).getValueType() == MVT::i1 &&
1534 !TLI.isOperationLegal(ISD::SIGN_EXTEND, MVT::i1)) {
1535 DebugLoc DL = N->getDebugLoc();
1536 SDValue ZExt = DAG.getNode(ISD::ZERO_EXTEND, DL, VT, N0.getOperand(0));
1537 return DAG.getNode(ISD::SUB, DL, VT, N1, ZExt);
1538 }
1539
Evan Chengb3a3d5e2010-04-28 07:10:39 +00001540 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00001541}
1542
Dan Gohman475871a2008-07-27 21:46:04 +00001543SDValue DAGCombiner::visitADDC(SDNode *N) {
1544 SDValue N0 = N->getOperand(0);
1545 SDValue N1 = N->getOperand(1);
Chris Lattner91153682007-03-04 20:03:15 +00001546 ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0);
1547 ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1);
Owen Andersone50ed302009-08-10 22:56:29 +00001548 EVT VT = N0.getValueType();
Scott Michelfdc40a02009-02-17 22:15:04 +00001549
Chris Lattner91153682007-03-04 20:03:15 +00001550 // If the flag result is dead, turn this into an ADD.
Craig Topper704e1a02012-01-07 18:31:09 +00001551 if (!N->hasAnyUseOfValue(1))
Craig Toppercc274522012-01-07 09:06:39 +00001552 return CombineTo(N, DAG.getNode(ISD::ADD, N->getDebugLoc(), VT, N0, N1),
Dale Johannesen874ae252009-06-02 03:12:52 +00001553 DAG.getNode(ISD::CARRY_FALSE,
Chris Lattnerf1b4eaf2010-12-21 02:38:05 +00001554 N->getDebugLoc(), MVT::Glue));
Scott Michelfdc40a02009-02-17 22:15:04 +00001555
Chris Lattner91153682007-03-04 20:03:15 +00001556 // canonicalize constant to RHS.
Dan Gohman0a4627d2008-06-23 15:29:14 +00001557 if (N0C && !N1C)
Bill Wendling14036c02009-01-30 02:38:00 +00001558 return DAG.getNode(ISD::ADDC, N->getDebugLoc(), N->getVTList(), N1, N0);
Scott Michelfdc40a02009-02-17 22:15:04 +00001559
Chris Lattnerb6541762007-03-04 20:40:38 +00001560 // fold (addc x, 0) -> x + no carry out
1561 if (N1C && N1C->isNullValue())
Dale Johannesen874ae252009-06-02 03:12:52 +00001562 return CombineTo(N, N0, DAG.getNode(ISD::CARRY_FALSE,
Chris Lattnerf1b4eaf2010-12-21 02:38:05 +00001563 N->getDebugLoc(), MVT::Glue));
Scott Michelfdc40a02009-02-17 22:15:04 +00001564
Sylvestre Ledru94c22712012-09-27 10:14:43 +00001565 // fold (addc a, b) -> (or a, b), CARRY_FALSE iff a and b share no bits.
Dan Gohman948d8ea2008-02-20 16:33:30 +00001566 APInt LHSZero, LHSOne;
1567 APInt RHSZero, RHSOne;
Rafael Espindola26c8dcc2012-04-04 12:51:34 +00001568 DAG.ComputeMaskedBits(N0, LHSZero, LHSOne);
Bill Wendling14036c02009-01-30 02:38:00 +00001569
Dan Gohman948d8ea2008-02-20 16:33:30 +00001570 if (LHSZero.getBoolValue()) {
Rafael Espindola26c8dcc2012-04-04 12:51:34 +00001571 DAG.ComputeMaskedBits(N1, RHSZero, RHSOne);
Scott Michelfdc40a02009-02-17 22:15:04 +00001572
Chris Lattnerb6541762007-03-04 20:40:38 +00001573 // If all possibly-set bits on the LHS are clear on the RHS, return an OR.
1574 // If all possibly-set bits on the RHS are clear on the LHS, return an OR.
Rafael Espindola26c8dcc2012-04-04 12:51:34 +00001575 if ((RHSZero & ~LHSZero) == ~LHSZero || (LHSZero & ~RHSZero) == ~RHSZero)
Bill Wendling14036c02009-01-30 02:38:00 +00001576 return CombineTo(N, DAG.getNode(ISD::OR, N->getDebugLoc(), VT, N0, N1),
Dale Johannesen874ae252009-06-02 03:12:52 +00001577 DAG.getNode(ISD::CARRY_FALSE,
Chris Lattnerf1b4eaf2010-12-21 02:38:05 +00001578 N->getDebugLoc(), MVT::Glue));
Chris Lattnerb6541762007-03-04 20:40:38 +00001579 }
Scott Michelfdc40a02009-02-17 22:15:04 +00001580
Dan Gohman475871a2008-07-27 21:46:04 +00001581 return SDValue();
Chris Lattner91153682007-03-04 20:03:15 +00001582}
1583
Dan Gohman475871a2008-07-27 21:46:04 +00001584SDValue DAGCombiner::visitADDE(SDNode *N) {
1585 SDValue N0 = N->getOperand(0);
1586 SDValue N1 = N->getOperand(1);
1587 SDValue CarryIn = N->getOperand(2);
Chris Lattner91153682007-03-04 20:03:15 +00001588 ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0);
1589 ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1);
Scott Michelfdc40a02009-02-17 22:15:04 +00001590
Chris Lattner91153682007-03-04 20:03:15 +00001591 // canonicalize constant to RHS
Dan Gohman0a4627d2008-06-23 15:29:14 +00001592 if (N0C && !N1C)
Bill Wendling14036c02009-01-30 02:38:00 +00001593 return DAG.getNode(ISD::ADDE, N->getDebugLoc(), N->getVTList(),
1594 N1, N0, CarryIn);
Scott Michelfdc40a02009-02-17 22:15:04 +00001595
Chris Lattnerb6541762007-03-04 20:40:38 +00001596 // fold (adde x, y, false) -> (addc x, y)
Dale Johannesen874ae252009-06-02 03:12:52 +00001597 if (CarryIn.getOpcode() == ISD::CARRY_FALSE)
Craig Toppercc274522012-01-07 09:06:39 +00001598 return DAG.getNode(ISD::ADDC, N->getDebugLoc(), N->getVTList(), N0, N1);
Scott Michelfdc40a02009-02-17 22:15:04 +00001599
Dan Gohman475871a2008-07-27 21:46:04 +00001600 return SDValue();
Chris Lattner91153682007-03-04 20:03:15 +00001601}
1602
Eric Christopher7bccf6a2011-02-16 04:50:12 +00001603// Since it may not be valid to emit a fold to zero for vector initializers
1604// check if we can before folding.
1605static SDValue tryFoldToZero(DebugLoc DL, const TargetLowering &TLI, EVT VT,
Owen Anderson95771af2011-02-25 21:41:48 +00001606 SelectionDAG &DAG, bool LegalOperations) {
Eric Christopher7bccf6a2011-02-16 04:50:12 +00001607 if (!VT.isVector()) {
1608 return DAG.getConstant(0, VT);
Dan Gohman71dc7c92011-05-17 22:20:36 +00001609 }
1610 if (!LegalOperations || TLI.isOperationLegal(ISD::BUILD_VECTOR, VT)) {
Eric Christopher7bccf6a2011-02-16 04:50:12 +00001611 // Produce a vector of zeros.
1612 SDValue El = DAG.getConstant(0, VT.getVectorElementType());
1613 std::vector<SDValue> Ops(VT.getVectorNumElements(), El);
1614 return DAG.getNode(ISD::BUILD_VECTOR, DL, VT,
1615 &Ops[0], Ops.size());
1616 }
1617 return SDValue();
1618}
1619
Dan Gohman475871a2008-07-27 21:46:04 +00001620SDValue DAGCombiner::visitSUB(SDNode *N) {
1621 SDValue N0 = N->getOperand(0);
1622 SDValue N1 = N->getOperand(1);
Gabor Greifba36cb52008-08-28 21:40:38 +00001623 ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0.getNode());
1624 ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1.getNode());
Eric Christopher7332e6e2011-07-14 01:12:15 +00001625 ConstantSDNode *N1C1 = N1.getOpcode() != ISD::ADD ? 0 :
1626 dyn_cast<ConstantSDNode>(N1.getOperand(1).getNode());
Owen Andersone50ed302009-08-10 22:56:29 +00001627 EVT VT = N0.getValueType();
Scott Michelfdc40a02009-02-17 22:15:04 +00001628
Dan Gohman7f321562007-06-25 16:23:39 +00001629 // fold vector ops
Duncan Sands83ec4b62008-06-06 12:08:01 +00001630 if (VT.isVector()) {
Dan Gohman475871a2008-07-27 21:46:04 +00001631 SDValue FoldedVOp = SimplifyVBinOp(N);
Gabor Greifba36cb52008-08-28 21:40:38 +00001632 if (FoldedVOp.getNode()) return FoldedVOp;
Craig Topper48b509c2012-12-10 08:12:29 +00001633
1634 // fold (sub x, 0) -> x, vector edition
1635 if (ISD::isBuildVectorAllZeros(N1.getNode()))
1636 return N0;
Dan Gohman05d92fe2007-07-13 20:03:40 +00001637 }
Bill Wendling2476e5d2008-12-10 22:36:00 +00001638
Chris Lattner854077d2005-10-17 01:07:11 +00001639 // fold (sub x, x) -> 0
Eric Christopher169e1552011-02-16 01:10:03 +00001640 // FIXME: Refactor this and xor and other similar operations together.
Eric Christopher7bccf6a2011-02-16 04:50:12 +00001641 if (N0 == N1)
1642 return tryFoldToZero(N->getDebugLoc(), TLI, VT, DAG, LegalOperations);
Nate Begeman1d4d4142005-09-01 00:19:25 +00001643 // fold (sub c1, c2) -> c1-c2
Nate Begeman646d7e22005-09-02 21:18:40 +00001644 if (N0C && N1C)
Bill Wendlingf3cbca22008-09-24 10:25:02 +00001645 return DAG.FoldConstantArithmetic(ISD::SUB, VT, N0C, N1C);
Chris Lattner05b57432005-10-11 06:07:15 +00001646 // fold (sub x, c) -> (add x, -c)
1647 if (N1C)
Bill Wendlingb0702e02009-01-30 02:42:10 +00001648 return DAG.getNode(ISD::ADD, N->getDebugLoc(), VT, N0,
Dan Gohman002e5d02008-03-13 22:13:53 +00001649 DAG.getConstant(-N1C->getAPIntValue(), VT));
Evan Cheng1ad0e8b2010-01-18 21:38:44 +00001650 // Canonicalize (sub -1, x) -> ~x, i.e. (xor x, -1)
1651 if (N0C && N0C->isAllOnesValue())
1652 return DAG.getNode(ISD::XOR, N->getDebugLoc(), VT, N1, N0);
Benjamin Kramer2c94b422011-01-29 12:34:05 +00001653 // fold A-(A-B) -> B
1654 if (N1.getOpcode() == ISD::SUB && N0 == N1.getOperand(0))
1655 return N1.getOperand(1);
Nate Begeman1d4d4142005-09-01 00:19:25 +00001656 // fold (A+B)-A -> B
Chris Lattner01b3d732005-09-28 22:28:18 +00001657 if (N0.getOpcode() == ISD::ADD && N0.getOperand(0) == N1)
Nate Begeman83e75ec2005-09-06 04:43:02 +00001658 return N0.getOperand(1);
Nate Begeman1d4d4142005-09-01 00:19:25 +00001659 // fold (A+B)-B -> A
Chris Lattner01b3d732005-09-28 22:28:18 +00001660 if (N0.getOpcode() == ISD::ADD && N0.getOperand(1) == N1)
Scott Michelfdc40a02009-02-17 22:15:04 +00001661 return N0.getOperand(0);
Eric Christopher7332e6e2011-07-14 01:12:15 +00001662 // fold C2-(A+C1) -> (C2-C1)-A
1663 if (N1.getOpcode() == ISD::ADD && N0C && N1C1) {
Nadav Rotem6dfabb62012-09-20 08:53:31 +00001664 SDValue NewC = DAG.getConstant(N0C->getAPIntValue() - N1C1->getAPIntValue(),
1665 VT);
Eric Christopher7332e6e2011-07-14 01:12:15 +00001666 return DAG.getNode(ISD::SUB, N->getDebugLoc(), VT, NewC,
Bill Wendling96cb1122012-07-19 00:04:14 +00001667 N1.getOperand(0));
Eric Christopher7332e6e2011-07-14 01:12:15 +00001668 }
Dale Johannesen7c7bc722008-12-23 23:47:22 +00001669 // fold ((A+(B+or-C))-B) -> A+or-C
Dale Johannesenfd3b7b72008-12-16 22:13:49 +00001670 if (N0.getOpcode() == ISD::ADD &&
Dale Johannesenf9cbc1f2008-12-23 23:01:27 +00001671 (N0.getOperand(1).getOpcode() == ISD::SUB ||
1672 N0.getOperand(1).getOpcode() == ISD::ADD) &&
Dale Johannesenfd3b7b72008-12-16 22:13:49 +00001673 N0.getOperand(1).getOperand(0) == N1)
Bill Wendlingb0702e02009-01-30 02:42:10 +00001674 return DAG.getNode(N0.getOperand(1).getOpcode(), N->getDebugLoc(), VT,
1675 N0.getOperand(0), N0.getOperand(1).getOperand(1));
Dale Johannesenf9cbc1f2008-12-23 23:01:27 +00001676 // fold ((A+(C+B))-B) -> A+C
1677 if (N0.getOpcode() == ISD::ADD &&
1678 N0.getOperand(1).getOpcode() == ISD::ADD &&
1679 N0.getOperand(1).getOperand(1) == N1)
Bill Wendlingb0702e02009-01-30 02:42:10 +00001680 return DAG.getNode(ISD::ADD, N->getDebugLoc(), VT,
1681 N0.getOperand(0), N0.getOperand(1).getOperand(0));
Dale Johannesen58e39b02008-12-23 01:59:54 +00001682 // fold ((A-(B-C))-C) -> A-B
1683 if (N0.getOpcode() == ISD::SUB &&
1684 N0.getOperand(1).getOpcode() == ISD::SUB &&
1685 N0.getOperand(1).getOperand(1) == N1)
Bill Wendlingb0702e02009-01-30 02:42:10 +00001686 return DAG.getNode(ISD::SUB, N->getDebugLoc(), VT,
1687 N0.getOperand(0), N0.getOperand(1).getOperand(0));
Bill Wendlingb0702e02009-01-30 02:42:10 +00001688
Dan Gohman613e0d82007-07-03 14:03:57 +00001689 // If either operand of a sub is undef, the result is undef
Dan Gohman70fb1ae2007-07-10 15:19:29 +00001690 if (N0.getOpcode() == ISD::UNDEF)
1691 return N0;
1692 if (N1.getOpcode() == ISD::UNDEF)
1693 return N1;
Dan Gohman7f321562007-06-25 16:23:39 +00001694
Dan Gohman6520e202008-10-18 02:06:02 +00001695 // If the relocation model supports it, consider symbol offsets.
1696 if (GlobalAddressSDNode *GA = dyn_cast<GlobalAddressSDNode>(N0))
Duncan Sands25cf2272008-11-24 14:53:14 +00001697 if (!LegalOperations && TLI.isOffsetFoldingLegal(GA)) {
Dan Gohman6520e202008-10-18 02:06:02 +00001698 // fold (sub Sym, c) -> Sym-c
1699 if (N1C && GA->getOpcode() == ISD::GlobalAddress)
Devang Patel0d881da2010-07-06 22:08:15 +00001700 return DAG.getGlobalAddress(GA->getGlobal(), N1C->getDebugLoc(), VT,
Dan Gohman6520e202008-10-18 02:06:02 +00001701 GA->getOffset() -
1702 (uint64_t)N1C->getSExtValue());
1703 // fold (sub Sym+c1, Sym+c2) -> c1-c2
1704 if (GlobalAddressSDNode *GB = dyn_cast<GlobalAddressSDNode>(N1))
1705 if (GA->getGlobal() == GB->getGlobal())
1706 return DAG.getConstant((uint64_t)GA->getOffset() - GB->getOffset(),
1707 VT);
1708 }
1709
Evan Chengb3a3d5e2010-04-28 07:10:39 +00001710 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00001711}
1712
Craig Toppercc274522012-01-07 09:06:39 +00001713SDValue DAGCombiner::visitSUBC(SDNode *N) {
1714 SDValue N0 = N->getOperand(0);
1715 SDValue N1 = N->getOperand(1);
1716 ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0);
1717 ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1);
1718 EVT VT = N0.getValueType();
1719
1720 // If the flag result is dead, turn this into an SUB.
Craig Topper704e1a02012-01-07 18:31:09 +00001721 if (!N->hasAnyUseOfValue(1))
Craig Toppercc274522012-01-07 09:06:39 +00001722 return CombineTo(N, DAG.getNode(ISD::SUB, N->getDebugLoc(), VT, N0, N1),
1723 DAG.getNode(ISD::CARRY_FALSE, N->getDebugLoc(),
1724 MVT::Glue));
1725
1726 // fold (subc x, x) -> 0 + no borrow
1727 if (N0 == N1)
1728 return CombineTo(N, DAG.getConstant(0, VT),
1729 DAG.getNode(ISD::CARRY_FALSE, N->getDebugLoc(),
1730 MVT::Glue));
1731
1732 // fold (subc x, 0) -> x + no borrow
1733 if (N1C && N1C->isNullValue())
1734 return CombineTo(N, N0, DAG.getNode(ISD::CARRY_FALSE, N->getDebugLoc(),
1735 MVT::Glue));
1736
1737 // Canonicalize (sub -1, x) -> ~x, i.e. (xor x, -1) + no borrow
1738 if (N0C && N0C->isAllOnesValue())
1739 return CombineTo(N, DAG.getNode(ISD::XOR, N->getDebugLoc(), VT, N1, N0),
1740 DAG.getNode(ISD::CARRY_FALSE, N->getDebugLoc(),
1741 MVT::Glue));
1742
1743 return SDValue();
1744}
1745
1746SDValue DAGCombiner::visitSUBE(SDNode *N) {
1747 SDValue N0 = N->getOperand(0);
1748 SDValue N1 = N->getOperand(1);
1749 SDValue CarryIn = N->getOperand(2);
1750
1751 // fold (sube x, y, false) -> (subc x, y)
1752 if (CarryIn.getOpcode() == ISD::CARRY_FALSE)
1753 return DAG.getNode(ISD::SUBC, N->getDebugLoc(), N->getVTList(), N0, N1);
1754
1755 return SDValue();
1756}
1757
Dan Gohman475871a2008-07-27 21:46:04 +00001758SDValue DAGCombiner::visitMUL(SDNode *N) {
1759 SDValue N0 = N->getOperand(0);
1760 SDValue N1 = N->getOperand(1);
Nate Begeman646d7e22005-09-02 21:18:40 +00001761 ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0);
1762 ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1);
Owen Andersone50ed302009-08-10 22:56:29 +00001763 EVT VT = N0.getValueType();
Scott Michelfdc40a02009-02-17 22:15:04 +00001764
Dan Gohman7f321562007-06-25 16:23:39 +00001765 // fold vector ops
Duncan Sands83ec4b62008-06-06 12:08:01 +00001766 if (VT.isVector()) {
Dan Gohman475871a2008-07-27 21:46:04 +00001767 SDValue FoldedVOp = SimplifyVBinOp(N);
Gabor Greifba36cb52008-08-28 21:40:38 +00001768 if (FoldedVOp.getNode()) return FoldedVOp;
Dan Gohman05d92fe2007-07-13 20:03:40 +00001769 }
Scott Michelfdc40a02009-02-17 22:15:04 +00001770
Dan Gohman613e0d82007-07-03 14:03:57 +00001771 // fold (mul x, undef) -> 0
Dan Gohmand595b5f2007-07-10 14:20:37 +00001772 if (N0.getOpcode() == ISD::UNDEF || N1.getOpcode() == ISD::UNDEF)
Dan Gohman613e0d82007-07-03 14:03:57 +00001773 return DAG.getConstant(0, VT);
Nate Begeman1d4d4142005-09-01 00:19:25 +00001774 // fold (mul c1, c2) -> c1*c2
Nate Begeman646d7e22005-09-02 21:18:40 +00001775 if (N0C && N1C)
Bill Wendlingf3cbca22008-09-24 10:25:02 +00001776 return DAG.FoldConstantArithmetic(ISD::MUL, VT, N0C, N1C);
Nate Begeman99801192005-09-07 23:25:52 +00001777 // canonicalize constant to RHS
Nate Begemana0e221d2005-10-18 00:28:13 +00001778 if (N0C && !N1C)
Bill Wendling9c8148a2009-01-30 02:45:56 +00001779 return DAG.getNode(ISD::MUL, N->getDebugLoc(), VT, N1, N0);
Nate Begeman1d4d4142005-09-01 00:19:25 +00001780 // fold (mul x, 0) -> 0
Nate Begeman646d7e22005-09-02 21:18:40 +00001781 if (N1C && N1C->isNullValue())
Nate Begeman83e75ec2005-09-06 04:43:02 +00001782 return N1;
Nate Begeman1d4d4142005-09-01 00:19:25 +00001783 // fold (mul x, -1) -> 0-x
Nate Begeman646d7e22005-09-02 21:18:40 +00001784 if (N1C && N1C->isAllOnesValue())
Bill Wendling9c8148a2009-01-30 02:45:56 +00001785 return DAG.getNode(ISD::SUB, N->getDebugLoc(), VT,
1786 DAG.getConstant(0, VT), N0);
Nate Begeman1d4d4142005-09-01 00:19:25 +00001787 // fold (mul x, (1 << c)) -> x << c
Dan Gohman002e5d02008-03-13 22:13:53 +00001788 if (N1C && N1C->getAPIntValue().isPowerOf2())
Bill Wendling9c8148a2009-01-30 02:45:56 +00001789 return DAG.getNode(ISD::SHL, N->getDebugLoc(), VT, N0,
Dan Gohman002e5d02008-03-13 22:13:53 +00001790 DAG.getConstant(N1C->getAPIntValue().logBase2(),
Owen Anderson95771af2011-02-25 21:41:48 +00001791 getShiftAmountTy(N0.getValueType())));
Chris Lattner3e6099b2005-10-30 06:41:49 +00001792 // fold (mul x, -(1 << c)) -> -(x << c) or (-x) << c
Chris Lattner66b8bc32009-03-09 20:22:18 +00001793 if (N1C && (-N1C->getAPIntValue()).isPowerOf2()) {
1794 unsigned Log2Val = (-N1C->getAPIntValue()).logBase2();
Scott Michelfdc40a02009-02-17 22:15:04 +00001795 // FIXME: If the input is something that is easily negated (e.g. a
Chris Lattner3e6099b2005-10-30 06:41:49 +00001796 // single-use add), we should put the negate there.
Bill Wendling9c8148a2009-01-30 02:45:56 +00001797 return DAG.getNode(ISD::SUB, N->getDebugLoc(), VT,
1798 DAG.getConstant(0, VT),
Bill Wendling73e16b22009-01-30 02:49:26 +00001799 DAG.getNode(ISD::SHL, N->getDebugLoc(), VT, N0,
Owen Anderson95771af2011-02-25 21:41:48 +00001800 DAG.getConstant(Log2Val,
1801 getShiftAmountTy(N0.getValueType()))));
Chris Lattner66b8bc32009-03-09 20:22:18 +00001802 }
Chris Lattner0b1a85f2006-03-01 03:44:24 +00001803 // (mul (shl X, c1), c2) -> (mul X, c2 << c1)
Bill Wendling73e16b22009-01-30 02:49:26 +00001804 if (N1C && N0.getOpcode() == ISD::SHL &&
Chris Lattner0b1a85f2006-03-01 03:44:24 +00001805 isa<ConstantSDNode>(N0.getOperand(1))) {
Bill Wendling9c8148a2009-01-30 02:45:56 +00001806 SDValue C3 = DAG.getNode(ISD::SHL, N->getDebugLoc(), VT,
1807 N1, N0.getOperand(1));
Gabor Greifba36cb52008-08-28 21:40:38 +00001808 AddToWorkList(C3.getNode());
Bill Wendling9c8148a2009-01-30 02:45:56 +00001809 return DAG.getNode(ISD::MUL, N->getDebugLoc(), VT,
1810 N0.getOperand(0), C3);
Chris Lattner0b1a85f2006-03-01 03:44:24 +00001811 }
Scott Michelfdc40a02009-02-17 22:15:04 +00001812
Chris Lattner0b1a85f2006-03-01 03:44:24 +00001813 // Change (mul (shl X, C), Y) -> (shl (mul X, Y), C) when the shift has one
1814 // use.
1815 {
Dan Gohman475871a2008-07-27 21:46:04 +00001816 SDValue Sh(0,0), Y(0,0);
Chris Lattner0b1a85f2006-03-01 03:44:24 +00001817 // Check for both (mul (shl X, C), Y) and (mul Y, (shl X, C)).
1818 if (N0.getOpcode() == ISD::SHL && isa<ConstantSDNode>(N0.getOperand(1)) &&
Gabor Greifba36cb52008-08-28 21:40:38 +00001819 N0.getNode()->hasOneUse()) {
Chris Lattner0b1a85f2006-03-01 03:44:24 +00001820 Sh = N0; Y = N1;
Scott Michelfdc40a02009-02-17 22:15:04 +00001821 } else if (N1.getOpcode() == ISD::SHL &&
Gabor Greif12632d22008-08-30 19:29:20 +00001822 isa<ConstantSDNode>(N1.getOperand(1)) &&
1823 N1.getNode()->hasOneUse()) {
Chris Lattner0b1a85f2006-03-01 03:44:24 +00001824 Sh = N1; Y = N0;
1825 }
Bill Wendling73e16b22009-01-30 02:49:26 +00001826
Gabor Greifba36cb52008-08-28 21:40:38 +00001827 if (Sh.getNode()) {
Bill Wendling9c8148a2009-01-30 02:45:56 +00001828 SDValue Mul = DAG.getNode(ISD::MUL, N->getDebugLoc(), VT,
1829 Sh.getOperand(0), Y);
1830 return DAG.getNode(ISD::SHL, N->getDebugLoc(), VT,
1831 Mul, Sh.getOperand(1));
Chris Lattner0b1a85f2006-03-01 03:44:24 +00001832 }
1833 }
Bill Wendling73e16b22009-01-30 02:49:26 +00001834
Chris Lattnera1deca32006-03-04 23:33:26 +00001835 // fold (mul (add x, c1), c2) -> (add (mul x, c2), c1*c2)
Scott Michelfdc40a02009-02-17 22:15:04 +00001836 if (N1C && N0.getOpcode() == ISD::ADD && N0.getNode()->hasOneUse() &&
Bill Wendling9c8148a2009-01-30 02:45:56 +00001837 isa<ConstantSDNode>(N0.getOperand(1)))
1838 return DAG.getNode(ISD::ADD, N->getDebugLoc(), VT,
1839 DAG.getNode(ISD::MUL, N0.getDebugLoc(), VT,
1840 N0.getOperand(0), N1),
1841 DAG.getNode(ISD::MUL, N1.getDebugLoc(), VT,
1842 N0.getOperand(1), N1));
Scott Michelfdc40a02009-02-17 22:15:04 +00001843
Nate Begemancd4d58c2006-02-03 06:46:56 +00001844 // reassociate mul
Bill Wendling35247c32009-01-30 00:45:56 +00001845 SDValue RMUL = ReassociateOps(ISD::MUL, N->getDebugLoc(), N0, N1);
Gabor Greifba36cb52008-08-28 21:40:38 +00001846 if (RMUL.getNode() != 0)
Nate Begemancd4d58c2006-02-03 06:46:56 +00001847 return RMUL;
Dan Gohman7f321562007-06-25 16:23:39 +00001848
Evan Chengb3a3d5e2010-04-28 07:10:39 +00001849 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00001850}
1851
Dan Gohman475871a2008-07-27 21:46:04 +00001852SDValue DAGCombiner::visitSDIV(SDNode *N) {
1853 SDValue N0 = N->getOperand(0);
1854 SDValue N1 = N->getOperand(1);
Gabor Greifba36cb52008-08-28 21:40:38 +00001855 ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0.getNode());
1856 ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1.getNode());
Owen Andersone50ed302009-08-10 22:56:29 +00001857 EVT VT = N->getValueType(0);
Nate Begeman1d4d4142005-09-01 00:19:25 +00001858
Dan Gohman7f321562007-06-25 16:23:39 +00001859 // fold vector ops
Duncan Sands83ec4b62008-06-06 12:08:01 +00001860 if (VT.isVector()) {
Dan Gohman475871a2008-07-27 21:46:04 +00001861 SDValue FoldedVOp = SimplifyVBinOp(N);
Gabor Greifba36cb52008-08-28 21:40:38 +00001862 if (FoldedVOp.getNode()) return FoldedVOp;
Dan Gohman05d92fe2007-07-13 20:03:40 +00001863 }
Scott Michelfdc40a02009-02-17 22:15:04 +00001864
Nate Begeman1d4d4142005-09-01 00:19:25 +00001865 // fold (sdiv c1, c2) -> c1/c2
Nate Begeman646d7e22005-09-02 21:18:40 +00001866 if (N0C && N1C && !N1C->isNullValue())
Bill Wendlingf3cbca22008-09-24 10:25:02 +00001867 return DAG.FoldConstantArithmetic(ISD::SDIV, VT, N0C, N1C);
Nate Begeman405e3ec2005-10-21 00:02:42 +00001868 // fold (sdiv X, 1) -> X
Eli Friedmanfd58cd72011-10-27 02:06:39 +00001869 if (N1C && N1C->getAPIntValue() == 1LL)
Nate Begeman405e3ec2005-10-21 00:02:42 +00001870 return N0;
1871 // fold (sdiv X, -1) -> 0-X
1872 if (N1C && N1C->isAllOnesValue())
Bill Wendling944d34b2009-01-30 02:52:17 +00001873 return DAG.getNode(ISD::SUB, N->getDebugLoc(), VT,
1874 DAG.getConstant(0, VT), N0);
Chris Lattner094c8fc2005-10-07 06:10:46 +00001875 // If we know the sign bits of both operands are zero, strength reduce to a
1876 // udiv instead. Handles (X&15) /s 4 -> X&15 >> 2
Duncan Sands83ec4b62008-06-06 12:08:01 +00001877 if (!VT.isVector()) {
Dan Gohman2e68b6f2008-02-25 21:11:39 +00001878 if (DAG.SignBitIsZero(N1) && DAG.SignBitIsZero(N0))
Bill Wendling944d34b2009-01-30 02:52:17 +00001879 return DAG.getNode(ISD::UDIV, N->getDebugLoc(), N1.getValueType(),
1880 N0, N1);
Chris Lattnerf32aac32008-01-27 23:32:17 +00001881 }
Nate Begemancd6a6ed2006-02-17 07:26:20 +00001882 // fold (sdiv X, pow2) -> simple ops after legalize
Eli Friedman1c663fe2011-12-07 03:55:52 +00001883 if (N1C && !N1C->isNullValue() &&
Eli Friedmanfd58cd72011-10-27 02:06:39 +00001884 (N1C->getAPIntValue().isPowerOf2() ||
1885 (-N1C->getAPIntValue()).isPowerOf2())) {
Nate Begeman405e3ec2005-10-21 00:02:42 +00001886 // If dividing by powers of two is cheap, then don't perform the following
1887 // fold.
1888 if (TLI.isPow2DivCheap())
Dan Gohman475871a2008-07-27 21:46:04 +00001889 return SDValue();
Bill Wendling944d34b2009-01-30 02:52:17 +00001890
Eli Friedmanfd58cd72011-10-27 02:06:39 +00001891 unsigned lg2 = N1C->getAPIntValue().countTrailingZeros();
Bill Wendling944d34b2009-01-30 02:52:17 +00001892
Chris Lattner8f4880b2006-02-16 08:02:36 +00001893 // Splat the sign bit into the register
Bill Wendling944d34b2009-01-30 02:52:17 +00001894 SDValue SGN = DAG.getNode(ISD::SRA, N->getDebugLoc(), VT, N0,
1895 DAG.getConstant(VT.getSizeInBits()-1,
Owen Anderson95771af2011-02-25 21:41:48 +00001896 getShiftAmountTy(N0.getValueType())));
Gabor Greifba36cb52008-08-28 21:40:38 +00001897 AddToWorkList(SGN.getNode());
Bill Wendling944d34b2009-01-30 02:52:17 +00001898
Chris Lattner8f4880b2006-02-16 08:02:36 +00001899 // Add (N0 < 0) ? abs2 - 1 : 0;
Bill Wendling944d34b2009-01-30 02:52:17 +00001900 SDValue SRL = DAG.getNode(ISD::SRL, N->getDebugLoc(), VT, SGN,
1901 DAG.getConstant(VT.getSizeInBits() - lg2,
Owen Anderson95771af2011-02-25 21:41:48 +00001902 getShiftAmountTy(SGN.getValueType())));
Bill Wendling944d34b2009-01-30 02:52:17 +00001903 SDValue ADD = DAG.getNode(ISD::ADD, N->getDebugLoc(), VT, N0, SRL);
Gabor Greifba36cb52008-08-28 21:40:38 +00001904 AddToWorkList(SRL.getNode());
1905 AddToWorkList(ADD.getNode()); // Divide by pow2
Bill Wendling944d34b2009-01-30 02:52:17 +00001906 SDValue SRA = DAG.getNode(ISD::SRA, N->getDebugLoc(), VT, ADD,
Owen Anderson95771af2011-02-25 21:41:48 +00001907 DAG.getConstant(lg2, getShiftAmountTy(ADD.getValueType())));
Bill Wendling944d34b2009-01-30 02:52:17 +00001908
Nate Begeman405e3ec2005-10-21 00:02:42 +00001909 // If we're dividing by a positive value, we're done. Otherwise, we must
1910 // negate the result.
Eli Friedmanfd58cd72011-10-27 02:06:39 +00001911 if (N1C->getAPIntValue().isNonNegative())
Nate Begeman405e3ec2005-10-21 00:02:42 +00001912 return SRA;
Bill Wendling944d34b2009-01-30 02:52:17 +00001913
Gabor Greifba36cb52008-08-28 21:40:38 +00001914 AddToWorkList(SRA.getNode());
Bill Wendling944d34b2009-01-30 02:52:17 +00001915 return DAG.getNode(ISD::SUB, N->getDebugLoc(), VT,
1916 DAG.getConstant(0, VT), SRA);
Nate Begeman405e3ec2005-10-21 00:02:42 +00001917 }
Bill Wendling944d34b2009-01-30 02:52:17 +00001918
Nate Begeman69575232005-10-20 02:15:44 +00001919 // if integer divide is expensive and we satisfy the requirements, emit an
1920 // alternate sequence.
Eli Friedmanfd58cd72011-10-27 02:06:39 +00001921 if (N1C && !N1C->isNullValue() && !TLI.isIntDivCheap()) {
Dan Gohman475871a2008-07-27 21:46:04 +00001922 SDValue Op = BuildSDIV(N);
Gabor Greifba36cb52008-08-28 21:40:38 +00001923 if (Op.getNode()) return Op;
Nate Begeman69575232005-10-20 02:15:44 +00001924 }
Dan Gohman7f321562007-06-25 16:23:39 +00001925
Dan Gohman613e0d82007-07-03 14:03:57 +00001926 // undef / X -> 0
1927 if (N0.getOpcode() == ISD::UNDEF)
1928 return DAG.getConstant(0, VT);
1929 // X / undef -> undef
1930 if (N1.getOpcode() == ISD::UNDEF)
1931 return N1;
Dan Gohman7f321562007-06-25 16:23:39 +00001932
Dan Gohman475871a2008-07-27 21:46:04 +00001933 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00001934}
1935
Dan Gohman475871a2008-07-27 21:46:04 +00001936SDValue DAGCombiner::visitUDIV(SDNode *N) {
1937 SDValue N0 = N->getOperand(0);
1938 SDValue N1 = N->getOperand(1);
Gabor Greifba36cb52008-08-28 21:40:38 +00001939 ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0.getNode());
1940 ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1.getNode());
Owen Andersone50ed302009-08-10 22:56:29 +00001941 EVT VT = N->getValueType(0);
Scott Michelfdc40a02009-02-17 22:15:04 +00001942
Dan Gohman7f321562007-06-25 16:23:39 +00001943 // fold vector ops
Duncan Sands83ec4b62008-06-06 12:08:01 +00001944 if (VT.isVector()) {
Dan Gohman475871a2008-07-27 21:46:04 +00001945 SDValue FoldedVOp = SimplifyVBinOp(N);
Gabor Greifba36cb52008-08-28 21:40:38 +00001946 if (FoldedVOp.getNode()) return FoldedVOp;
Dan Gohman05d92fe2007-07-13 20:03:40 +00001947 }
Scott Michelfdc40a02009-02-17 22:15:04 +00001948
Nate Begeman1d4d4142005-09-01 00:19:25 +00001949 // fold (udiv c1, c2) -> c1/c2
Nate Begeman646d7e22005-09-02 21:18:40 +00001950 if (N0C && N1C && !N1C->isNullValue())
Bill Wendlingf3cbca22008-09-24 10:25:02 +00001951 return DAG.FoldConstantArithmetic(ISD::UDIV, VT, N0C, N1C);
Nate Begeman1d4d4142005-09-01 00:19:25 +00001952 // fold (udiv x, (1 << c)) -> x >>u c
Dan Gohman002e5d02008-03-13 22:13:53 +00001953 if (N1C && N1C->getAPIntValue().isPowerOf2())
Scott Michelfdc40a02009-02-17 22:15:04 +00001954 return DAG.getNode(ISD::SRL, N->getDebugLoc(), VT, N0,
Dan Gohman002e5d02008-03-13 22:13:53 +00001955 DAG.getConstant(N1C->getAPIntValue().logBase2(),
Owen Anderson95771af2011-02-25 21:41:48 +00001956 getShiftAmountTy(N0.getValueType())));
Sylvestre Ledru94c22712012-09-27 10:14:43 +00001957 // fold (udiv x, (shl c, y)) -> x >>u (log2(c)+y) iff c is power of 2
Nate Begemanfb5e4bd2006-02-05 07:20:23 +00001958 if (N1.getOpcode() == ISD::SHL) {
1959 if (ConstantSDNode *SHC = dyn_cast<ConstantSDNode>(N1.getOperand(0))) {
Dan Gohman002e5d02008-03-13 22:13:53 +00001960 if (SHC->getAPIntValue().isPowerOf2()) {
Owen Andersone50ed302009-08-10 22:56:29 +00001961 EVT ADDVT = N1.getOperand(1).getValueType();
Bill Wendling07d85142009-01-30 02:55:25 +00001962 SDValue Add = DAG.getNode(ISD::ADD, N->getDebugLoc(), ADDVT,
1963 N1.getOperand(1),
1964 DAG.getConstant(SHC->getAPIntValue()
1965 .logBase2(),
1966 ADDVT));
Gabor Greifba36cb52008-08-28 21:40:38 +00001967 AddToWorkList(Add.getNode());
Bill Wendling07d85142009-01-30 02:55:25 +00001968 return DAG.getNode(ISD::SRL, N->getDebugLoc(), VT, N0, Add);
Nate Begemanfb5e4bd2006-02-05 07:20:23 +00001969 }
1970 }
1971 }
Nate Begeman69575232005-10-20 02:15:44 +00001972 // fold (udiv x, c) -> alternate
Dan Gohman002e5d02008-03-13 22:13:53 +00001973 if (N1C && !N1C->isNullValue() && !TLI.isIntDivCheap()) {
Dan Gohman475871a2008-07-27 21:46:04 +00001974 SDValue Op = BuildUDIV(N);
Gabor Greifba36cb52008-08-28 21:40:38 +00001975 if (Op.getNode()) return Op;
Chris Lattnere9936d12005-10-22 18:50:15 +00001976 }
Dan Gohman7f321562007-06-25 16:23:39 +00001977
Dan Gohman613e0d82007-07-03 14:03:57 +00001978 // undef / X -> 0
1979 if (N0.getOpcode() == ISD::UNDEF)
1980 return DAG.getConstant(0, VT);
1981 // X / undef -> undef
1982 if (N1.getOpcode() == ISD::UNDEF)
1983 return N1;
Dan Gohman7f321562007-06-25 16:23:39 +00001984
Dan Gohman475871a2008-07-27 21:46:04 +00001985 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00001986}
1987
Dan Gohman475871a2008-07-27 21:46:04 +00001988SDValue DAGCombiner::visitSREM(SDNode *N) {
1989 SDValue N0 = N->getOperand(0);
1990 SDValue N1 = N->getOperand(1);
Nate Begeman646d7e22005-09-02 21:18:40 +00001991 ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0);
1992 ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1);
Owen Andersone50ed302009-08-10 22:56:29 +00001993 EVT VT = N->getValueType(0);
Scott Michelfdc40a02009-02-17 22:15:04 +00001994
Nate Begeman1d4d4142005-09-01 00:19:25 +00001995 // fold (srem c1, c2) -> c1%c2
Nate Begeman646d7e22005-09-02 21:18:40 +00001996 if (N0C && N1C && !N1C->isNullValue())
Bill Wendlingf3cbca22008-09-24 10:25:02 +00001997 return DAG.FoldConstantArithmetic(ISD::SREM, VT, N0C, N1C);
Nate Begeman07ed4172005-10-10 21:26:48 +00001998 // If we know the sign bits of both operands are zero, strength reduce to a
1999 // urem instead. Handles (X & 0x0FFFFFFF) %s 16 -> X&15
Duncan Sands83ec4b62008-06-06 12:08:01 +00002000 if (!VT.isVector()) {
Dan Gohman2e68b6f2008-02-25 21:11:39 +00002001 if (DAG.SignBitIsZero(N1) && DAG.SignBitIsZero(N0))
Bill Wendling6d3bf8c2009-01-30 02:57:00 +00002002 return DAG.getNode(ISD::UREM, N->getDebugLoc(), VT, N0, N1);
Chris Lattneree339f42008-01-27 23:21:58 +00002003 }
Scott Michelfdc40a02009-02-17 22:15:04 +00002004
Dan Gohman77003042007-11-26 23:46:11 +00002005 // If X/C can be simplified by the division-by-constant logic, lower
2006 // X%C to the equivalent of X-X/C*C.
Chris Lattner26d29902006-10-12 20:58:32 +00002007 if (N1C && !N1C->isNullValue()) {
Bill Wendling6d3bf8c2009-01-30 02:57:00 +00002008 SDValue Div = DAG.getNode(ISD::SDIV, N->getDebugLoc(), VT, N0, N1);
Gabor Greifba36cb52008-08-28 21:40:38 +00002009 AddToWorkList(Div.getNode());
2010 SDValue OptimizedDiv = combine(Div.getNode());
2011 if (OptimizedDiv.getNode() && OptimizedDiv.getNode() != Div.getNode()) {
Bill Wendling6d3bf8c2009-01-30 02:57:00 +00002012 SDValue Mul = DAG.getNode(ISD::MUL, N->getDebugLoc(), VT,
2013 OptimizedDiv, N1);
2014 SDValue Sub = DAG.getNode(ISD::SUB, N->getDebugLoc(), VT, N0, Mul);
Gabor Greifba36cb52008-08-28 21:40:38 +00002015 AddToWorkList(Mul.getNode());
Dan Gohman77003042007-11-26 23:46:11 +00002016 return Sub;
2017 }
Chris Lattner26d29902006-10-12 20:58:32 +00002018 }
Scott Michelfdc40a02009-02-17 22:15:04 +00002019
Dan Gohman613e0d82007-07-03 14:03:57 +00002020 // undef % X -> 0
2021 if (N0.getOpcode() == ISD::UNDEF)
2022 return DAG.getConstant(0, VT);
2023 // X % undef -> undef
2024 if (N1.getOpcode() == ISD::UNDEF)
2025 return N1;
Dan Gohman7f321562007-06-25 16:23:39 +00002026
Dan Gohman475871a2008-07-27 21:46:04 +00002027 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00002028}
2029
Dan Gohman475871a2008-07-27 21:46:04 +00002030SDValue DAGCombiner::visitUREM(SDNode *N) {
2031 SDValue N0 = N->getOperand(0);
2032 SDValue N1 = N->getOperand(1);
Nate Begeman646d7e22005-09-02 21:18:40 +00002033 ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0);
2034 ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1);
Owen Andersone50ed302009-08-10 22:56:29 +00002035 EVT VT = N->getValueType(0);
Scott Michelfdc40a02009-02-17 22:15:04 +00002036
Nate Begeman1d4d4142005-09-01 00:19:25 +00002037 // fold (urem c1, c2) -> c1%c2
Nate Begeman646d7e22005-09-02 21:18:40 +00002038 if (N0C && N1C && !N1C->isNullValue())
Bill Wendlingf3cbca22008-09-24 10:25:02 +00002039 return DAG.FoldConstantArithmetic(ISD::UREM, VT, N0C, N1C);
Nate Begeman07ed4172005-10-10 21:26:48 +00002040 // fold (urem x, pow2) -> (and x, pow2-1)
Dan Gohman002e5d02008-03-13 22:13:53 +00002041 if (N1C && !N1C->isNullValue() && N1C->getAPIntValue().isPowerOf2())
Bill Wendling6d3bf8c2009-01-30 02:57:00 +00002042 return DAG.getNode(ISD::AND, N->getDebugLoc(), VT, N0,
Dan Gohman002e5d02008-03-13 22:13:53 +00002043 DAG.getConstant(N1C->getAPIntValue()-1,VT));
Nate Begemanc031e332006-02-05 07:36:48 +00002044 // fold (urem x, (shl pow2, y)) -> (and x, (add (shl pow2, y), -1))
2045 if (N1.getOpcode() == ISD::SHL) {
2046 if (ConstantSDNode *SHC = dyn_cast<ConstantSDNode>(N1.getOperand(0))) {
Dan Gohman002e5d02008-03-13 22:13:53 +00002047 if (SHC->getAPIntValue().isPowerOf2()) {
Dan Gohman475871a2008-07-27 21:46:04 +00002048 SDValue Add =
Bill Wendling6d3bf8c2009-01-30 02:57:00 +00002049 DAG.getNode(ISD::ADD, N->getDebugLoc(), VT, N1,
Duncan Sands83ec4b62008-06-06 12:08:01 +00002050 DAG.getConstant(APInt::getAllOnesValue(VT.getSizeInBits()),
Dan Gohman002e5d02008-03-13 22:13:53 +00002051 VT));
Gabor Greifba36cb52008-08-28 21:40:38 +00002052 AddToWorkList(Add.getNode());
Bill Wendling6d3bf8c2009-01-30 02:57:00 +00002053 return DAG.getNode(ISD::AND, N->getDebugLoc(), VT, N0, Add);
Nate Begemanc031e332006-02-05 07:36:48 +00002054 }
2055 }
2056 }
Scott Michelfdc40a02009-02-17 22:15:04 +00002057
Dan Gohman77003042007-11-26 23:46:11 +00002058 // If X/C can be simplified by the division-by-constant logic, lower
2059 // X%C to the equivalent of X-X/C*C.
Chris Lattner26d29902006-10-12 20:58:32 +00002060 if (N1C && !N1C->isNullValue()) {
Bill Wendling6d3bf8c2009-01-30 02:57:00 +00002061 SDValue Div = DAG.getNode(ISD::UDIV, N->getDebugLoc(), VT, N0, N1);
Dan Gohman942ca7f2008-09-08 16:59:01 +00002062 AddToWorkList(Div.getNode());
Gabor Greifba36cb52008-08-28 21:40:38 +00002063 SDValue OptimizedDiv = combine(Div.getNode());
2064 if (OptimizedDiv.getNode() && OptimizedDiv.getNode() != Div.getNode()) {
Bill Wendling6d3bf8c2009-01-30 02:57:00 +00002065 SDValue Mul = DAG.getNode(ISD::MUL, N->getDebugLoc(), VT,
2066 OptimizedDiv, N1);
2067 SDValue Sub = DAG.getNode(ISD::SUB, N->getDebugLoc(), VT, N0, Mul);
Gabor Greifba36cb52008-08-28 21:40:38 +00002068 AddToWorkList(Mul.getNode());
Dan Gohman77003042007-11-26 23:46:11 +00002069 return Sub;
2070 }
Chris Lattner26d29902006-10-12 20:58:32 +00002071 }
Scott Michelfdc40a02009-02-17 22:15:04 +00002072
Dan Gohman613e0d82007-07-03 14:03:57 +00002073 // undef % X -> 0
2074 if (N0.getOpcode() == ISD::UNDEF)
2075 return DAG.getConstant(0, VT);
2076 // X % undef -> undef
2077 if (N1.getOpcode() == ISD::UNDEF)
2078 return N1;
Dan Gohman7f321562007-06-25 16:23:39 +00002079
Dan Gohman475871a2008-07-27 21:46:04 +00002080 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00002081}
2082
Dan Gohman475871a2008-07-27 21:46:04 +00002083SDValue DAGCombiner::visitMULHS(SDNode *N) {
2084 SDValue N0 = N->getOperand(0);
2085 SDValue N1 = N->getOperand(1);
Nate Begeman646d7e22005-09-02 21:18:40 +00002086 ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1);
Owen Andersone50ed302009-08-10 22:56:29 +00002087 EVT VT = N->getValueType(0);
Chris Lattnerde1c3602010-12-13 08:39:01 +00002088 DebugLoc DL = N->getDebugLoc();
Scott Michelfdc40a02009-02-17 22:15:04 +00002089
Nate Begeman1d4d4142005-09-01 00:19:25 +00002090 // fold (mulhs x, 0) -> 0
Nate Begeman646d7e22005-09-02 21:18:40 +00002091 if (N1C && N1C->isNullValue())
Nate Begeman83e75ec2005-09-06 04:43:02 +00002092 return N1;
Nate Begeman1d4d4142005-09-01 00:19:25 +00002093 // fold (mulhs x, 1) -> (sra x, size(x)-1)
Dan Gohman002e5d02008-03-13 22:13:53 +00002094 if (N1C && N1C->getAPIntValue() == 1)
Bill Wendling326411d2009-01-30 03:00:18 +00002095 return DAG.getNode(ISD::SRA, N->getDebugLoc(), N0.getValueType(), N0,
2096 DAG.getConstant(N0.getValueType().getSizeInBits() - 1,
Owen Anderson95771af2011-02-25 21:41:48 +00002097 getShiftAmountTy(N0.getValueType())));
Dan Gohman613e0d82007-07-03 14:03:57 +00002098 // fold (mulhs x, undef) -> 0
Dan Gohmand595b5f2007-07-10 14:20:37 +00002099 if (N0.getOpcode() == ISD::UNDEF || N1.getOpcode() == ISD::UNDEF)
Dan Gohman613e0d82007-07-03 14:03:57 +00002100 return DAG.getConstant(0, VT);
Dan Gohman7f321562007-06-25 16:23:39 +00002101
Chris Lattnerde1c3602010-12-13 08:39:01 +00002102 // If the type twice as wide is legal, transform the mulhs to a wider multiply
2103 // plus a shift.
2104 if (VT.isSimple() && !VT.isVector()) {
2105 MVT Simple = VT.getSimpleVT();
2106 unsigned SimpleSize = Simple.getSizeInBits();
2107 EVT NewVT = EVT::getIntegerVT(*DAG.getContext(), SimpleSize*2);
2108 if (TLI.isOperationLegal(ISD::MUL, NewVT)) {
2109 N0 = DAG.getNode(ISD::SIGN_EXTEND, DL, NewVT, N0);
2110 N1 = DAG.getNode(ISD::SIGN_EXTEND, DL, NewVT, N1);
2111 N1 = DAG.getNode(ISD::MUL, DL, NewVT, N0, N1);
Chris Lattner1a0fbe22010-12-15 05:51:39 +00002112 N1 = DAG.getNode(ISD::SRL, DL, NewVT, N1,
Owen Anderson95771af2011-02-25 21:41:48 +00002113 DAG.getConstant(SimpleSize, getShiftAmountTy(N1.getValueType())));
Chris Lattnerde1c3602010-12-13 08:39:01 +00002114 return DAG.getNode(ISD::TRUNCATE, DL, VT, N1);
2115 }
2116 }
Owen Anderson95771af2011-02-25 21:41:48 +00002117
Dan Gohman475871a2008-07-27 21:46:04 +00002118 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00002119}
2120
Dan Gohman475871a2008-07-27 21:46:04 +00002121SDValue DAGCombiner::visitMULHU(SDNode *N) {
2122 SDValue N0 = N->getOperand(0);
2123 SDValue N1 = N->getOperand(1);
Nate Begeman646d7e22005-09-02 21:18:40 +00002124 ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1);
Owen Andersone50ed302009-08-10 22:56:29 +00002125 EVT VT = N->getValueType(0);
Chris Lattnerde1c3602010-12-13 08:39:01 +00002126 DebugLoc DL = N->getDebugLoc();
Scott Michelfdc40a02009-02-17 22:15:04 +00002127
Nate Begeman1d4d4142005-09-01 00:19:25 +00002128 // fold (mulhu x, 0) -> 0
Nate Begeman646d7e22005-09-02 21:18:40 +00002129 if (N1C && N1C->isNullValue())
Nate Begeman83e75ec2005-09-06 04:43:02 +00002130 return N1;
Nate Begeman1d4d4142005-09-01 00:19:25 +00002131 // fold (mulhu x, 1) -> 0
Dan Gohman002e5d02008-03-13 22:13:53 +00002132 if (N1C && N1C->getAPIntValue() == 1)
Nate Begeman83e75ec2005-09-06 04:43:02 +00002133 return DAG.getConstant(0, N0.getValueType());
Dan Gohman613e0d82007-07-03 14:03:57 +00002134 // fold (mulhu x, undef) -> 0
Dan Gohmand595b5f2007-07-10 14:20:37 +00002135 if (N0.getOpcode() == ISD::UNDEF || N1.getOpcode() == ISD::UNDEF)
Dan Gohman613e0d82007-07-03 14:03:57 +00002136 return DAG.getConstant(0, VT);
Dan Gohman7f321562007-06-25 16:23:39 +00002137
Chris Lattnerde1c3602010-12-13 08:39:01 +00002138 // If the type twice as wide is legal, transform the mulhu to a wider multiply
2139 // plus a shift.
2140 if (VT.isSimple() && !VT.isVector()) {
2141 MVT Simple = VT.getSimpleVT();
2142 unsigned SimpleSize = Simple.getSizeInBits();
2143 EVT NewVT = EVT::getIntegerVT(*DAG.getContext(), SimpleSize*2);
2144 if (TLI.isOperationLegal(ISD::MUL, NewVT)) {
2145 N0 = DAG.getNode(ISD::ZERO_EXTEND, DL, NewVT, N0);
2146 N1 = DAG.getNode(ISD::ZERO_EXTEND, DL, NewVT, N1);
2147 N1 = DAG.getNode(ISD::MUL, DL, NewVT, N0, N1);
2148 N1 = DAG.getNode(ISD::SRL, DL, NewVT, N1,
Owen Anderson95771af2011-02-25 21:41:48 +00002149 DAG.getConstant(SimpleSize, getShiftAmountTy(N1.getValueType())));
Chris Lattnerde1c3602010-12-13 08:39:01 +00002150 return DAG.getNode(ISD::TRUNCATE, DL, VT, N1);
2151 }
2152 }
Owen Anderson95771af2011-02-25 21:41:48 +00002153
Dan Gohman475871a2008-07-27 21:46:04 +00002154 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00002155}
2156
Dan Gohman389079b2007-10-08 17:57:15 +00002157/// SimplifyNodeWithTwoResults - Perform optimizations common to nodes that
2158/// compute two values. LoOp and HiOp give the opcodes for the two computations
2159/// that are being performed. Return true if a simplification was made.
2160///
Scott Michelfdc40a02009-02-17 22:15:04 +00002161SDValue DAGCombiner::SimplifyNodeWithTwoResults(SDNode *N, unsigned LoOp,
Dan Gohman475871a2008-07-27 21:46:04 +00002162 unsigned HiOp) {
Dan Gohman389079b2007-10-08 17:57:15 +00002163 // If the high half is not needed, just compute the low half.
Evan Cheng44711942007-11-08 09:25:29 +00002164 bool HiExists = N->hasAnyUseOfValue(1);
2165 if (!HiExists &&
Duncan Sands25cf2272008-11-24 14:53:14 +00002166 (!LegalOperations ||
Dan Gohman389079b2007-10-08 17:57:15 +00002167 TLI.isOperationLegal(LoOp, N->getValueType(0)))) {
Bill Wendling826d1142009-01-30 03:08:40 +00002168 SDValue Res = DAG.getNode(LoOp, N->getDebugLoc(), N->getValueType(0),
2169 N->op_begin(), N->getNumOperands());
Chris Lattner5eee4272008-01-26 01:09:19 +00002170 return CombineTo(N, Res, Res);
Dan Gohman389079b2007-10-08 17:57:15 +00002171 }
2172
2173 // If the low half is not needed, just compute the high half.
Evan Cheng44711942007-11-08 09:25:29 +00002174 bool LoExists = N->hasAnyUseOfValue(0);
2175 if (!LoExists &&
Duncan Sands25cf2272008-11-24 14:53:14 +00002176 (!LegalOperations ||
Dan Gohman389079b2007-10-08 17:57:15 +00002177 TLI.isOperationLegal(HiOp, N->getValueType(1)))) {
Bill Wendling826d1142009-01-30 03:08:40 +00002178 SDValue Res = DAG.getNode(HiOp, N->getDebugLoc(), N->getValueType(1),
2179 N->op_begin(), N->getNumOperands());
Chris Lattner5eee4272008-01-26 01:09:19 +00002180 return CombineTo(N, Res, Res);
Dan Gohman389079b2007-10-08 17:57:15 +00002181 }
2182
Evan Cheng44711942007-11-08 09:25:29 +00002183 // If both halves are used, return as it is.
2184 if (LoExists && HiExists)
Dan Gohman475871a2008-07-27 21:46:04 +00002185 return SDValue();
Evan Cheng44711942007-11-08 09:25:29 +00002186
2187 // If the two computed results can be simplified separately, separate them.
Evan Cheng44711942007-11-08 09:25:29 +00002188 if (LoExists) {
Bill Wendling826d1142009-01-30 03:08:40 +00002189 SDValue Lo = DAG.getNode(LoOp, N->getDebugLoc(), N->getValueType(0),
2190 N->op_begin(), N->getNumOperands());
Gabor Greifba36cb52008-08-28 21:40:38 +00002191 AddToWorkList(Lo.getNode());
2192 SDValue LoOpt = combine(Lo.getNode());
2193 if (LoOpt.getNode() && LoOpt.getNode() != Lo.getNode() &&
Duncan Sands25cf2272008-11-24 14:53:14 +00002194 (!LegalOperations ||
Duncan Sandsd4b9c172008-06-13 19:07:40 +00002195 TLI.isOperationLegal(LoOpt.getOpcode(), LoOpt.getValueType())))
Chris Lattner5eee4272008-01-26 01:09:19 +00002196 return CombineTo(N, LoOpt, LoOpt);
Dan Gohman389079b2007-10-08 17:57:15 +00002197 }
2198
Evan Cheng44711942007-11-08 09:25:29 +00002199 if (HiExists) {
Bill Wendling826d1142009-01-30 03:08:40 +00002200 SDValue Hi = DAG.getNode(HiOp, N->getDebugLoc(), N->getValueType(1),
Duncan Sands25cf2272008-11-24 14:53:14 +00002201 N->op_begin(), N->getNumOperands());
Gabor Greifba36cb52008-08-28 21:40:38 +00002202 AddToWorkList(Hi.getNode());
2203 SDValue HiOpt = combine(Hi.getNode());
2204 if (HiOpt.getNode() && HiOpt != Hi &&
Duncan Sands25cf2272008-11-24 14:53:14 +00002205 (!LegalOperations ||
Duncan Sandsd4b9c172008-06-13 19:07:40 +00002206 TLI.isOperationLegal(HiOpt.getOpcode(), HiOpt.getValueType())))
Chris Lattner5eee4272008-01-26 01:09:19 +00002207 return CombineTo(N, HiOpt, HiOpt);
Evan Cheng44711942007-11-08 09:25:29 +00002208 }
Bill Wendling826d1142009-01-30 03:08:40 +00002209
Dan Gohman475871a2008-07-27 21:46:04 +00002210 return SDValue();
Dan Gohman389079b2007-10-08 17:57:15 +00002211}
2212
Dan Gohman475871a2008-07-27 21:46:04 +00002213SDValue DAGCombiner::visitSMUL_LOHI(SDNode *N) {
2214 SDValue Res = SimplifyNodeWithTwoResults(N, ISD::MUL, ISD::MULHS);
Gabor Greifba36cb52008-08-28 21:40:38 +00002215 if (Res.getNode()) return Res;
Dan Gohman389079b2007-10-08 17:57:15 +00002216
Chris Lattner33e77d32010-12-15 06:04:19 +00002217 EVT VT = N->getValueType(0);
2218 DebugLoc DL = N->getDebugLoc();
2219
2220 // If the type twice as wide is legal, transform the mulhu to a wider multiply
2221 // plus a shift.
2222 if (VT.isSimple() && !VT.isVector()) {
2223 MVT Simple = VT.getSimpleVT();
2224 unsigned SimpleSize = Simple.getSizeInBits();
2225 EVT NewVT = EVT::getIntegerVT(*DAG.getContext(), SimpleSize*2);
2226 if (TLI.isOperationLegal(ISD::MUL, NewVT)) {
2227 SDValue Lo = DAG.getNode(ISD::SIGN_EXTEND, DL, NewVT, N->getOperand(0));
2228 SDValue Hi = DAG.getNode(ISD::SIGN_EXTEND, DL, NewVT, N->getOperand(1));
2229 Lo = DAG.getNode(ISD::MUL, DL, NewVT, Lo, Hi);
2230 // Compute the high part as N1.
2231 Hi = DAG.getNode(ISD::SRL, DL, NewVT, Lo,
Owen Anderson95771af2011-02-25 21:41:48 +00002232 DAG.getConstant(SimpleSize, getShiftAmountTy(Lo.getValueType())));
Chris Lattner33e77d32010-12-15 06:04:19 +00002233 Hi = DAG.getNode(ISD::TRUNCATE, DL, VT, Hi);
2234 // Compute the low part as N0.
2235 Lo = DAG.getNode(ISD::TRUNCATE, DL, VT, Lo);
2236 return CombineTo(N, Lo, Hi);
2237 }
2238 }
Owen Anderson95771af2011-02-25 21:41:48 +00002239
Dan Gohman475871a2008-07-27 21:46:04 +00002240 return SDValue();
Dan Gohman389079b2007-10-08 17:57:15 +00002241}
2242
Dan Gohman475871a2008-07-27 21:46:04 +00002243SDValue DAGCombiner::visitUMUL_LOHI(SDNode *N) {
2244 SDValue Res = SimplifyNodeWithTwoResults(N, ISD::MUL, ISD::MULHU);
Gabor Greifba36cb52008-08-28 21:40:38 +00002245 if (Res.getNode()) return Res;
Dan Gohman389079b2007-10-08 17:57:15 +00002246
Chris Lattner33e77d32010-12-15 06:04:19 +00002247 EVT VT = N->getValueType(0);
2248 DebugLoc DL = N->getDebugLoc();
Owen Anderson95771af2011-02-25 21:41:48 +00002249
Chris Lattner33e77d32010-12-15 06:04:19 +00002250 // If the type twice as wide is legal, transform the mulhu to a wider multiply
2251 // plus a shift.
2252 if (VT.isSimple() && !VT.isVector()) {
2253 MVT Simple = VT.getSimpleVT();
2254 unsigned SimpleSize = Simple.getSizeInBits();
2255 EVT NewVT = EVT::getIntegerVT(*DAG.getContext(), SimpleSize*2);
2256 if (TLI.isOperationLegal(ISD::MUL, NewVT)) {
2257 SDValue Lo = DAG.getNode(ISD::ZERO_EXTEND, DL, NewVT, N->getOperand(0));
2258 SDValue Hi = DAG.getNode(ISD::ZERO_EXTEND, DL, NewVT, N->getOperand(1));
2259 Lo = DAG.getNode(ISD::MUL, DL, NewVT, Lo, Hi);
2260 // Compute the high part as N1.
2261 Hi = DAG.getNode(ISD::SRL, DL, NewVT, Lo,
Owen Anderson95771af2011-02-25 21:41:48 +00002262 DAG.getConstant(SimpleSize, getShiftAmountTy(Lo.getValueType())));
Chris Lattner33e77d32010-12-15 06:04:19 +00002263 Hi = DAG.getNode(ISD::TRUNCATE, DL, VT, Hi);
2264 // Compute the low part as N0.
2265 Lo = DAG.getNode(ISD::TRUNCATE, DL, VT, Lo);
2266 return CombineTo(N, Lo, Hi);
2267 }
2268 }
Owen Anderson95771af2011-02-25 21:41:48 +00002269
Dan Gohman475871a2008-07-27 21:46:04 +00002270 return SDValue();
Dan Gohman389079b2007-10-08 17:57:15 +00002271}
2272
Benjamin Kramerf55d26e2011-05-21 18:31:55 +00002273SDValue DAGCombiner::visitSMULO(SDNode *N) {
2274 // (smulo x, 2) -> (saddo x, x)
2275 if (ConstantSDNode *C2 = dyn_cast<ConstantSDNode>(N->getOperand(1)))
2276 if (C2->getAPIntValue() == 2)
2277 return DAG.getNode(ISD::SADDO, N->getDebugLoc(), N->getVTList(),
2278 N->getOperand(0), N->getOperand(0));
2279
2280 return SDValue();
2281}
2282
2283SDValue DAGCombiner::visitUMULO(SDNode *N) {
2284 // (umulo x, 2) -> (uaddo x, x)
2285 if (ConstantSDNode *C2 = dyn_cast<ConstantSDNode>(N->getOperand(1)))
2286 if (C2->getAPIntValue() == 2)
2287 return DAG.getNode(ISD::UADDO, N->getDebugLoc(), N->getVTList(),
2288 N->getOperand(0), N->getOperand(0));
2289
2290 return SDValue();
2291}
2292
Dan Gohman475871a2008-07-27 21:46:04 +00002293SDValue DAGCombiner::visitSDIVREM(SDNode *N) {
2294 SDValue Res = SimplifyNodeWithTwoResults(N, ISD::SDIV, ISD::SREM);
Gabor Greifba36cb52008-08-28 21:40:38 +00002295 if (Res.getNode()) return Res;
Scott Michelfdc40a02009-02-17 22:15:04 +00002296
Dan Gohman475871a2008-07-27 21:46:04 +00002297 return SDValue();
Dan Gohman389079b2007-10-08 17:57:15 +00002298}
2299
Dan Gohman475871a2008-07-27 21:46:04 +00002300SDValue DAGCombiner::visitUDIVREM(SDNode *N) {
2301 SDValue Res = SimplifyNodeWithTwoResults(N, ISD::UDIV, ISD::UREM);
Gabor Greifba36cb52008-08-28 21:40:38 +00002302 if (Res.getNode()) return Res;
Scott Michelfdc40a02009-02-17 22:15:04 +00002303
Dan Gohman475871a2008-07-27 21:46:04 +00002304 return SDValue();
Dan Gohman389079b2007-10-08 17:57:15 +00002305}
2306
Chris Lattner35e5c142006-05-05 05:51:50 +00002307/// SimplifyBinOpWithSameOpcodeHands - If this is a binary operator with
2308/// two operands of the same opcode, try to simplify it.
Dan Gohman475871a2008-07-27 21:46:04 +00002309SDValue DAGCombiner::SimplifyBinOpWithSameOpcodeHands(SDNode *N) {
2310 SDValue N0 = N->getOperand(0), N1 = N->getOperand(1);
Owen Andersone50ed302009-08-10 22:56:29 +00002311 EVT VT = N0.getValueType();
Chris Lattner35e5c142006-05-05 05:51:50 +00002312 assert(N0.getOpcode() == N1.getOpcode() && "Bad input!");
Scott Michelfdc40a02009-02-17 22:15:04 +00002313
Dan Gohmanff00a552010-01-14 03:08:49 +00002314 // Bail early if none of these transforms apply.
2315 if (N0.getNode()->getNumOperands() == 0) return SDValue();
2316
Chris Lattner540121f2006-05-05 06:31:05 +00002317 // For each of OP in AND/OR/XOR:
2318 // fold (OP (zext x), (zext y)) -> (zext (OP x, y))
2319 // fold (OP (sext x), (sext y)) -> (sext (OP x, y))
2320 // fold (OP (aext x), (aext y)) -> (aext (OP x, y))
Dan Gohman4e39e9d2010-06-24 14:30:44 +00002321 // fold (OP (trunc x), (trunc y)) -> (trunc (OP x, y)) (if trunc isn't free)
Nate Begeman93e0ed32009-12-03 07:11:29 +00002322 //
2323 // do not sink logical op inside of a vector extend, since it may combine
2324 // into a vsetcc.
Evan Chengd40d03e2010-01-06 19:38:29 +00002325 EVT Op0VT = N0.getOperand(0).getValueType();
2326 if ((N0.getOpcode() == ISD::ZERO_EXTEND ||
Dan Gohman97121ba2009-04-08 00:15:30 +00002327 N0.getOpcode() == ISD::SIGN_EXTEND ||
Evan Chenge5b51ac2010-04-17 06:13:15 +00002328 // Avoid infinite looping with PromoteIntBinOp.
2329 (N0.getOpcode() == ISD::ANY_EXTEND &&
2330 (!LegalTypes || TLI.isTypeDesirableForOp(N->getOpcode(), Op0VT))) ||
Dan Gohman4e39e9d2010-06-24 14:30:44 +00002331 (N0.getOpcode() == ISD::TRUNCATE &&
2332 (!TLI.isZExtFree(VT, Op0VT) ||
2333 !TLI.isTruncateFree(Op0VT, VT)) &&
2334 TLI.isTypeLegal(Op0VT))) &&
Nate Begeman93e0ed32009-12-03 07:11:29 +00002335 !VT.isVector() &&
Evan Chengd40d03e2010-01-06 19:38:29 +00002336 Op0VT == N1.getOperand(0).getValueType() &&
2337 (!LegalOperations || TLI.isOperationLegal(N->getOpcode(), Op0VT))) {
Bill Wendlingb74c8672009-01-30 19:25:47 +00002338 SDValue ORNode = DAG.getNode(N->getOpcode(), N0.getDebugLoc(),
2339 N0.getOperand(0).getValueType(),
2340 N0.getOperand(0), N1.getOperand(0));
Gabor Greifba36cb52008-08-28 21:40:38 +00002341 AddToWorkList(ORNode.getNode());
Bill Wendlingb74c8672009-01-30 19:25:47 +00002342 return DAG.getNode(N0.getOpcode(), N->getDebugLoc(), VT, ORNode);
Chris Lattner35e5c142006-05-05 05:51:50 +00002343 }
Scott Michelfdc40a02009-02-17 22:15:04 +00002344
Chris Lattnera3dc3f62006-05-05 06:10:43 +00002345 // For each of OP in SHL/SRL/SRA/AND...
2346 // fold (and (OP x, z), (OP y, z)) -> (OP (and x, y), z)
2347 // fold (or (OP x, z), (OP y, z)) -> (OP (or x, y), z)
2348 // fold (xor (OP x, z), (OP y, z)) -> (OP (xor x, y), z)
Chris Lattner35e5c142006-05-05 05:51:50 +00002349 if ((N0.getOpcode() == ISD::SHL || N0.getOpcode() == ISD::SRL ||
Chris Lattnera3dc3f62006-05-05 06:10:43 +00002350 N0.getOpcode() == ISD::SRA || N0.getOpcode() == ISD::AND) &&
Chris Lattner35e5c142006-05-05 05:51:50 +00002351 N0.getOperand(1) == N1.getOperand(1)) {
Bill Wendlingb74c8672009-01-30 19:25:47 +00002352 SDValue ORNode = DAG.getNode(N->getOpcode(), N0.getDebugLoc(),
2353 N0.getOperand(0).getValueType(),
2354 N0.getOperand(0), N1.getOperand(0));
Gabor Greifba36cb52008-08-28 21:40:38 +00002355 AddToWorkList(ORNode.getNode());
Bill Wendlingb74c8672009-01-30 19:25:47 +00002356 return DAG.getNode(N0.getOpcode(), N->getDebugLoc(), VT,
2357 ORNode, N0.getOperand(1));
Chris Lattner35e5c142006-05-05 05:51:50 +00002358 }
Scott Michelfdc40a02009-02-17 22:15:04 +00002359
Nadav Rotem4ac90812012-04-01 19:31:22 +00002360 // Simplify xor/and/or (bitcast(A), bitcast(B)) -> bitcast(op (A,B))
2361 // Only perform this optimization after type legalization and before
2362 // LegalizeVectorOprs. LegalizeVectorOprs promotes vector operations by
2363 // adding bitcasts. For example (xor v4i32) is promoted to (v2i64), and
2364 // we don't want to undo this promotion.
2365 // We also handle SCALAR_TO_VECTOR because xor/or/and operations are cheaper
2366 // on scalars.
Nadav Rotem6dfabb62012-09-20 08:53:31 +00002367 if ((N0.getOpcode() == ISD::BITCAST ||
2368 N0.getOpcode() == ISD::SCALAR_TO_VECTOR) &&
2369 Level == AfterLegalizeTypes) {
Nadav Rotem4ac90812012-04-01 19:31:22 +00002370 SDValue In0 = N0.getOperand(0);
2371 SDValue In1 = N1.getOperand(0);
2372 EVT In0Ty = In0.getValueType();
2373 EVT In1Ty = In1.getValueType();
Nadav Rotem6dfabb62012-09-20 08:53:31 +00002374 DebugLoc DL = N->getDebugLoc();
2375 // If both incoming values are integers, and the original types are the
2376 // same.
Nadav Rotem4ac90812012-04-01 19:31:22 +00002377 if (In0Ty.isInteger() && In1Ty.isInteger() && In0Ty == In1Ty) {
Nadav Rotem6dfabb62012-09-20 08:53:31 +00002378 SDValue Op = DAG.getNode(N->getOpcode(), DL, In0Ty, In0, In1);
2379 SDValue BC = DAG.getNode(N0.getOpcode(), DL, VT, Op);
Nadav Rotem4ac90812012-04-01 19:31:22 +00002380 AddToWorkList(Op.getNode());
2381 return BC;
2382 }
2383 }
2384
2385 // Xor/and/or are indifferent to the swizzle operation (shuffle of one value).
2386 // Simplify xor/and/or (shuff(A), shuff(B)) -> shuff(op (A,B))
2387 // If both shuffles use the same mask, and both shuffle within a single
2388 // vector, then it is worthwhile to move the swizzle after the operation.
2389 // The type-legalizer generates this pattern when loading illegal
2390 // vector types from memory. In many cases this allows additional shuffle
2391 // optimizations.
Craig Topperf9204232012-04-09 07:19:09 +00002392 if (N0.getOpcode() == ISD::VECTOR_SHUFFLE && Level < AfterLegalizeDAG &&
2393 N0.getOperand(1).getOpcode() == ISD::UNDEF &&
2394 N1.getOperand(1).getOpcode() == ISD::UNDEF) {
Nadav Rotem4ac90812012-04-01 19:31:22 +00002395 ShuffleVectorSDNode *SVN0 = cast<ShuffleVectorSDNode>(N0);
2396 ShuffleVectorSDNode *SVN1 = cast<ShuffleVectorSDNode>(N1);
Craig Topperf9204232012-04-09 07:19:09 +00002397
2398 assert(N0.getOperand(0).getValueType() == N1.getOperand(1).getValueType() &&
2399 "Inputs to shuffles are not the same type");
Nadav Rotem4ac90812012-04-01 19:31:22 +00002400
2401 unsigned NumElts = VT.getVectorNumElements();
Nadav Rotem4ac90812012-04-01 19:31:22 +00002402
2403 // Check that both shuffles use the same mask. The masks are known to be of
2404 // the same length because the result vector type is the same.
2405 bool SameMask = true;
2406 for (unsigned i = 0; i != NumElts; ++i) {
2407 int Idx0 = SVN0->getMaskElt(i);
2408 int Idx1 = SVN1->getMaskElt(i);
2409 if (Idx0 != Idx1) {
2410 SameMask = false;
2411 break;
2412 }
2413 }
2414
Craig Topperf9204232012-04-09 07:19:09 +00002415 if (SameMask) {
2416 SDValue Op = DAG.getNode(N->getOpcode(), N->getDebugLoc(), VT,
2417 N0.getOperand(0), N1.getOperand(0));
Nadav Rotem4ac90812012-04-01 19:31:22 +00002418 AddToWorkList(Op.getNode());
Craig Topperf9204232012-04-09 07:19:09 +00002419 return DAG.getVectorShuffle(VT, N->getDebugLoc(), Op,
2420 DAG.getUNDEF(VT), &SVN0->getMask()[0]);
Nadav Rotem4ac90812012-04-01 19:31:22 +00002421 }
2422 }
Craig Topperf9204232012-04-09 07:19:09 +00002423
Dan Gohman475871a2008-07-27 21:46:04 +00002424 return SDValue();
Chris Lattner35e5c142006-05-05 05:51:50 +00002425}
2426
Dan Gohman475871a2008-07-27 21:46:04 +00002427SDValue DAGCombiner::visitAND(SDNode *N) {
2428 SDValue N0 = N->getOperand(0);
2429 SDValue N1 = N->getOperand(1);
2430 SDValue LL, LR, RL, RR, CC0, CC1;
Nate Begeman646d7e22005-09-02 21:18:40 +00002431 ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0);
2432 ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1);
Owen Andersone50ed302009-08-10 22:56:29 +00002433 EVT VT = N1.getValueType();
Dan Gohman6900a392010-03-04 00:23:16 +00002434 unsigned BitWidth = VT.getScalarType().getSizeInBits();
Scott Michelfdc40a02009-02-17 22:15:04 +00002435
Dan Gohman7f321562007-06-25 16:23:39 +00002436 // fold vector ops
Duncan Sands83ec4b62008-06-06 12:08:01 +00002437 if (VT.isVector()) {
Dan Gohman475871a2008-07-27 21:46:04 +00002438 SDValue FoldedVOp = SimplifyVBinOp(N);
Gabor Greifba36cb52008-08-28 21:40:38 +00002439 if (FoldedVOp.getNode()) return FoldedVOp;
Craig Topper9472b4f2012-12-08 22:49:19 +00002440
2441 // fold (and x, 0) -> 0, vector edition
2442 if (ISD::isBuildVectorAllZeros(N0.getNode()))
2443 return N0;
2444 if (ISD::isBuildVectorAllZeros(N1.getNode()))
2445 return N1;
2446
2447 // fold (and x, -1) -> x, vector edition
2448 if (ISD::isBuildVectorAllOnes(N0.getNode()))
2449 return N1;
2450 if (ISD::isBuildVectorAllOnes(N1.getNode()))
2451 return N0;
Dan Gohman05d92fe2007-07-13 20:03:40 +00002452 }
Scott Michelfdc40a02009-02-17 22:15:04 +00002453
Dan Gohman613e0d82007-07-03 14:03:57 +00002454 // fold (and x, undef) -> 0
Dan Gohmand595b5f2007-07-10 14:20:37 +00002455 if (N0.getOpcode() == ISD::UNDEF || N1.getOpcode() == ISD::UNDEF)
Dan Gohman613e0d82007-07-03 14:03:57 +00002456 return DAG.getConstant(0, VT);
Nate Begeman1d4d4142005-09-01 00:19:25 +00002457 // fold (and c1, c2) -> c1&c2
Nate Begeman646d7e22005-09-02 21:18:40 +00002458 if (N0C && N1C)
Bill Wendlingf3cbca22008-09-24 10:25:02 +00002459 return DAG.FoldConstantArithmetic(ISD::AND, VT, N0C, N1C);
Nate Begeman99801192005-09-07 23:25:52 +00002460 // canonicalize constant to RHS
Nate Begemana0e221d2005-10-18 00:28:13 +00002461 if (N0C && !N1C)
Bill Wendlingfc4b6772009-02-01 11:19:36 +00002462 return DAG.getNode(ISD::AND, N->getDebugLoc(), VT, N1, N0);
Nate Begeman1d4d4142005-09-01 00:19:25 +00002463 // fold (and x, -1) -> x
Nate Begeman646d7e22005-09-02 21:18:40 +00002464 if (N1C && N1C->isAllOnesValue())
Nate Begeman83e75ec2005-09-06 04:43:02 +00002465 return N0;
2466 // if (and x, c) is known to be zero, return 0
Dan Gohman475871a2008-07-27 21:46:04 +00002467 if (N1C && DAG.MaskedValueIsZero(SDValue(N, 0),
Dan Gohman2e68b6f2008-02-25 21:11:39 +00002468 APInt::getAllOnesValue(BitWidth)))
Nate Begeman83e75ec2005-09-06 04:43:02 +00002469 return DAG.getConstant(0, VT);
Nate Begemancd4d58c2006-02-03 06:46:56 +00002470 // reassociate and
Bill Wendling35247c32009-01-30 00:45:56 +00002471 SDValue RAND = ReassociateOps(ISD::AND, N->getDebugLoc(), N0, N1);
Gabor Greifba36cb52008-08-28 21:40:38 +00002472 if (RAND.getNode() != 0)
Nate Begemancd4d58c2006-02-03 06:46:56 +00002473 return RAND;
Bill Wendling7d9f2b92010-03-03 00:35:56 +00002474 // fold (and (or x, C), D) -> D if (C & D) == D
Nate Begeman5dc7e862005-11-02 18:42:59 +00002475 if (N1C && N0.getOpcode() == ISD::OR)
Nate Begeman1d4d4142005-09-01 00:19:25 +00002476 if (ConstantSDNode *ORI = dyn_cast<ConstantSDNode>(N0.getOperand(1)))
Dan Gohman002e5d02008-03-13 22:13:53 +00002477 if ((ORI->getAPIntValue() & N1C->getAPIntValue()) == N1C->getAPIntValue())
Nate Begeman83e75ec2005-09-06 04:43:02 +00002478 return N1;
Chris Lattner3603cd62006-02-02 07:17:31 +00002479 // fold (and (any_ext V), c) -> (zero_ext V) if 'and' only clears top bits.
2480 if (N1C && N0.getOpcode() == ISD::ANY_EXTEND) {
Dan Gohman475871a2008-07-27 21:46:04 +00002481 SDValue N0Op0 = N0.getOperand(0);
Dan Gohman2e68b6f2008-02-25 21:11:39 +00002482 APInt Mask = ~N1C->getAPIntValue();
Jay Foad40f8f622010-12-07 08:25:19 +00002483 Mask = Mask.trunc(N0Op0.getValueSizeInBits());
Dan Gohman2e68b6f2008-02-25 21:11:39 +00002484 if (DAG.MaskedValueIsZero(N0Op0, Mask)) {
Bill Wendling2627a882009-01-30 20:43:18 +00002485 SDValue Zext = DAG.getNode(ISD::ZERO_EXTEND, N->getDebugLoc(),
2486 N0.getValueType(), N0Op0);
Scott Michelfdc40a02009-02-17 22:15:04 +00002487
Chris Lattner1ec05d12006-03-01 21:47:21 +00002488 // Replace uses of the AND with uses of the Zero extend node.
2489 CombineTo(N, Zext);
Scott Michelfdc40a02009-02-17 22:15:04 +00002490
Chris Lattner3603cd62006-02-02 07:17:31 +00002491 // We actually want to replace all uses of the any_extend with the
2492 // zero_extend, to avoid duplicating things. This will later cause this
2493 // AND to be folded.
Gabor Greifba36cb52008-08-28 21:40:38 +00002494 CombineTo(N0.getNode(), Zext);
Dan Gohman475871a2008-07-27 21:46:04 +00002495 return SDValue(N, 0); // Return N so it doesn't get rechecked!
Chris Lattner3603cd62006-02-02 07:17:31 +00002496 }
2497 }
James Molloy6259dcd2012-02-20 12:02:38 +00002498 // similarly fold (and (X (load ([non_ext|any_ext|zero_ext] V))), c) ->
2499 // (X (load ([non_ext|zero_ext] V))) if 'and' only clears top bits which must
2500 // already be zero by virtue of the width of the base type of the load.
2501 //
2502 // the 'X' node here can either be nothing or an extract_vector_elt to catch
2503 // more cases.
2504 if ((N0.getOpcode() == ISD::EXTRACT_VECTOR_ELT &&
2505 N0.getOperand(0).getOpcode() == ISD::LOAD) ||
2506 N0.getOpcode() == ISD::LOAD) {
2507 LoadSDNode *Load = cast<LoadSDNode>( (N0.getOpcode() == ISD::LOAD) ?
2508 N0 : N0.getOperand(0) );
2509
2510 // Get the constant (if applicable) the zero'th operand is being ANDed with.
2511 // This can be a pure constant or a vector splat, in which case we treat the
2512 // vector as a scalar and use the splat value.
2513 APInt Constant = APInt::getNullValue(1);
2514 if (const ConstantSDNode *C = dyn_cast<ConstantSDNode>(N1)) {
2515 Constant = C->getAPIntValue();
2516 } else if (BuildVectorSDNode *Vector = dyn_cast<BuildVectorSDNode>(N1)) {
2517 APInt SplatValue, SplatUndef;
2518 unsigned SplatBitSize;
2519 bool HasAnyUndefs;
2520 bool IsSplat = Vector->isConstantSplat(SplatValue, SplatUndef,
2521 SplatBitSize, HasAnyUndefs);
2522 if (IsSplat) {
2523 // Undef bits can contribute to a possible optimisation if set, so
2524 // set them.
2525 SplatValue |= SplatUndef;
2526
2527 // The splat value may be something like "0x00FFFFFF", which means 0 for
2528 // the first vector value and FF for the rest, repeating. We need a mask
2529 // that will apply equally to all members of the vector, so AND all the
2530 // lanes of the constant together.
2531 EVT VT = Vector->getValueType(0);
2532 unsigned BitWidth = VT.getVectorElementType().getSizeInBits();
Silviu Baranga3d5e1612012-09-05 08:57:21 +00002533
2534 // If the splat value has been compressed to a bitlength lower
2535 // than the size of the vector lane, we need to re-expand it to
2536 // the lane size.
2537 if (BitWidth > SplatBitSize)
2538 for (SplatValue = SplatValue.zextOrTrunc(BitWidth);
2539 SplatBitSize < BitWidth;
2540 SplatBitSize = SplatBitSize * 2)
2541 SplatValue |= SplatValue.shl(SplatBitSize);
2542
James Molloy6259dcd2012-02-20 12:02:38 +00002543 Constant = APInt::getAllOnesValue(BitWidth);
Silviu Baranga3d5e1612012-09-05 08:57:21 +00002544 for (unsigned i = 0, n = SplatBitSize/BitWidth; i < n; ++i)
James Molloy6259dcd2012-02-20 12:02:38 +00002545 Constant &= SplatValue.lshr(i*BitWidth).zextOrTrunc(BitWidth);
2546 }
2547 }
2548
2549 // If we want to change an EXTLOAD to a ZEXTLOAD, ensure a ZEXTLOAD is
2550 // actually legal and isn't going to get expanded, else this is a false
2551 // optimisation.
2552 bool CanZextLoadProfitably = TLI.isLoadExtLegal(ISD::ZEXTLOAD,
2553 Load->getMemoryVT());
2554
2555 // Resize the constant to the same size as the original memory access before
2556 // extension. If it is still the AllOnesValue then this AND is completely
2557 // unneeded.
2558 Constant =
2559 Constant.zextOrTrunc(Load->getMemoryVT().getScalarType().getSizeInBits());
2560
2561 bool B;
2562 switch (Load->getExtensionType()) {
2563 default: B = false; break;
2564 case ISD::EXTLOAD: B = CanZextLoadProfitably; break;
2565 case ISD::ZEXTLOAD:
2566 case ISD::NON_EXTLOAD: B = true; break;
2567 }
2568
2569 if (B && Constant.isAllOnesValue()) {
2570 // If the load type was an EXTLOAD, convert to ZEXTLOAD in order to
2571 // preserve semantics once we get rid of the AND.
2572 SDValue NewLoad(Load, 0);
2573 if (Load->getExtensionType() == ISD::EXTLOAD) {
2574 NewLoad = DAG.getLoad(Load->getAddressingMode(), ISD::ZEXTLOAD,
2575 Load->getValueType(0), Load->getDebugLoc(),
2576 Load->getChain(), Load->getBasePtr(),
2577 Load->getOffset(), Load->getMemoryVT(),
2578 Load->getMemOperand());
2579 // Replace uses of the EXTLOAD with the new ZEXTLOAD.
Hal Finkeld65e4632012-06-20 15:42:48 +00002580 if (Load->getNumValues() == 3) {
2581 // PRE/POST_INC loads have 3 values.
2582 SDValue To[] = { NewLoad.getValue(0), NewLoad.getValue(1),
2583 NewLoad.getValue(2) };
2584 CombineTo(Load, To, 3, true);
2585 } else {
2586 CombineTo(Load, NewLoad.getValue(0), NewLoad.getValue(1));
2587 }
James Molloy6259dcd2012-02-20 12:02:38 +00002588 }
2589
2590 // Fold the AND away, taking care not to fold to the old load node if we
2591 // replaced it.
2592 CombineTo(N, (N0.getNode() == Load) ? NewLoad : N0);
2593
2594 return SDValue(N, 0); // Return N so it doesn't get rechecked!
2595 }
2596 }
Nate Begeman39ee1ac2005-09-09 19:49:52 +00002597 // fold (and (setcc x), (setcc y)) -> (setcc (and x, y))
2598 if (isSetCCEquivalent(N0, LL, LR, CC0) && isSetCCEquivalent(N1, RL, RR, CC1)){
2599 ISD::CondCode Op0 = cast<CondCodeSDNode>(CC0)->get();
2600 ISD::CondCode Op1 = cast<CondCodeSDNode>(CC1)->get();
Scott Michelfdc40a02009-02-17 22:15:04 +00002601
Nate Begeman39ee1ac2005-09-09 19:49:52 +00002602 if (LR == RR && isa<ConstantSDNode>(LR) && Op0 == Op1 &&
Duncan Sands83ec4b62008-06-06 12:08:01 +00002603 LL.getValueType().isInteger()) {
Bill Wendling2627a882009-01-30 20:43:18 +00002604 // fold (and (seteq X, 0), (seteq Y, 0)) -> (seteq (or X, Y), 0)
Dan Gohman002e5d02008-03-13 22:13:53 +00002605 if (cast<ConstantSDNode>(LR)->isNullValue() && Op1 == ISD::SETEQ) {
Bill Wendling2627a882009-01-30 20:43:18 +00002606 SDValue ORNode = DAG.getNode(ISD::OR, N0.getDebugLoc(),
2607 LR.getValueType(), LL, RL);
Gabor Greifba36cb52008-08-28 21:40:38 +00002608 AddToWorkList(ORNode.getNode());
Bill Wendling2627a882009-01-30 20:43:18 +00002609 return DAG.getSetCC(N->getDebugLoc(), VT, ORNode, LR, Op1);
Nate Begeman39ee1ac2005-09-09 19:49:52 +00002610 }
Bill Wendling2627a882009-01-30 20:43:18 +00002611 // fold (and (seteq X, -1), (seteq Y, -1)) -> (seteq (and X, Y), -1)
Nate Begeman39ee1ac2005-09-09 19:49:52 +00002612 if (cast<ConstantSDNode>(LR)->isAllOnesValue() && Op1 == ISD::SETEQ) {
Bill Wendling2627a882009-01-30 20:43:18 +00002613 SDValue ANDNode = DAG.getNode(ISD::AND, N0.getDebugLoc(),
2614 LR.getValueType(), LL, RL);
Gabor Greifba36cb52008-08-28 21:40:38 +00002615 AddToWorkList(ANDNode.getNode());
Bill Wendling2627a882009-01-30 20:43:18 +00002616 return DAG.getSetCC(N->getDebugLoc(), VT, ANDNode, LR, Op1);
Nate Begeman39ee1ac2005-09-09 19:49:52 +00002617 }
Bill Wendling2627a882009-01-30 20:43:18 +00002618 // fold (and (setgt X, -1), (setgt Y, -1)) -> (setgt (or X, Y), -1)
Nate Begeman39ee1ac2005-09-09 19:49:52 +00002619 if (cast<ConstantSDNode>(LR)->isAllOnesValue() && Op1 == ISD::SETGT) {
Bill Wendling2627a882009-01-30 20:43:18 +00002620 SDValue ORNode = DAG.getNode(ISD::OR, N0.getDebugLoc(),
2621 LR.getValueType(), LL, RL);
Gabor Greifba36cb52008-08-28 21:40:38 +00002622 AddToWorkList(ORNode.getNode());
Bill Wendling2627a882009-01-30 20:43:18 +00002623 return DAG.getSetCC(N->getDebugLoc(), VT, ORNode, LR, Op1);
Nate Begeman39ee1ac2005-09-09 19:49:52 +00002624 }
2625 }
2626 // canonicalize equivalent to ll == rl
2627 if (LL == RR && LR == RL) {
2628 Op1 = ISD::getSetCCSwappedOperands(Op1);
2629 std::swap(RL, RR);
2630 }
2631 if (LL == RL && LR == RR) {
Duncan Sands83ec4b62008-06-06 12:08:01 +00002632 bool isInteger = LL.getValueType().isInteger();
Nate Begeman39ee1ac2005-09-09 19:49:52 +00002633 ISD::CondCode Result = ISD::getSetCCAndOperation(Op0, Op1, isInteger);
Chris Lattner6e1c6232008-10-28 07:11:07 +00002634 if (Result != ISD::SETCC_INVALID &&
Patrik Hagglund34525f92012-12-11 11:14:33 +00002635 (!LegalOperations || TLI.isCondCodeLegal(Result, LL.getValueType())))
Bill Wendling2627a882009-01-30 20:43:18 +00002636 return DAG.getSetCC(N->getDebugLoc(), N0.getValueType(),
2637 LL, LR, Result);
Nate Begeman39ee1ac2005-09-09 19:49:52 +00002638 }
2639 }
Chris Lattner35e5c142006-05-05 05:51:50 +00002640
Bill Wendling2627a882009-01-30 20:43:18 +00002641 // Simplify: (and (op x...), (op y...)) -> (op (and x, y))
Chris Lattner35e5c142006-05-05 05:51:50 +00002642 if (N0.getOpcode() == N1.getOpcode()) {
Dan Gohman475871a2008-07-27 21:46:04 +00002643 SDValue Tmp = SimplifyBinOpWithSameOpcodeHands(N);
Gabor Greifba36cb52008-08-28 21:40:38 +00002644 if (Tmp.getNode()) return Tmp;
Nate Begeman39ee1ac2005-09-09 19:49:52 +00002645 }
Scott Michelfdc40a02009-02-17 22:15:04 +00002646
Nate Begemande996292006-02-03 22:24:05 +00002647 // fold (and (sign_extend_inreg x, i16 to i32), 1) -> (and x, 1)
2648 // fold (and (sra)) -> (and (srl)) when possible.
Duncan Sands83ec4b62008-06-06 12:08:01 +00002649 if (!VT.isVector() &&
Dan Gohman475871a2008-07-27 21:46:04 +00002650 SimplifyDemandedBits(SDValue(N, 0)))
2651 return SDValue(N, 0);
Evan Chengd40d03e2010-01-06 19:38:29 +00002652
Nate Begemanded49632005-10-13 03:11:28 +00002653 // fold (zext_inreg (extload x)) -> (zextload x)
Gabor Greifba36cb52008-08-28 21:40:38 +00002654 if (ISD::isEXTLoad(N0.getNode()) && ISD::isUNINDEXEDLoad(N0.getNode())) {
Evan Cheng466685d2006-10-09 20:57:25 +00002655 LoadSDNode *LN0 = cast<LoadSDNode>(N0);
Dan Gohman8a55ce42009-09-23 21:02:20 +00002656 EVT MemVT = LN0->getMemoryVT();
Nate Begemanbfd65a02005-10-13 18:34:58 +00002657 // If we zero all the possible extended bits, then we can turn this into
2658 // a zextload if we are running before legalize or the operation is legal.
Dan Gohman6900a392010-03-04 00:23:16 +00002659 unsigned BitWidth = N1.getValueType().getScalarType().getSizeInBits();
Dan Gohman2e68b6f2008-02-25 21:11:39 +00002660 if (DAG.MaskedValueIsZero(N1, APInt::getHighBitsSet(BitWidth,
Dan Gohman6900a392010-03-04 00:23:16 +00002661 BitWidth - MemVT.getScalarType().getSizeInBits())) &&
Duncan Sands25cf2272008-11-24 14:53:14 +00002662 ((!LegalOperations && !LN0->isVolatile()) ||
Dan Gohman8a55ce42009-09-23 21:02:20 +00002663 TLI.isLoadExtLegal(ISD::ZEXTLOAD, MemVT))) {
Stuart Hastingsa9011292011-02-16 16:23:55 +00002664 SDValue ExtLoad = DAG.getExtLoad(ISD::ZEXTLOAD, N0.getDebugLoc(), VT,
Bill Wendling2627a882009-01-30 20:43:18 +00002665 LN0->getChain(), LN0->getBasePtr(),
Chris Lattner3d6ccfb2010-09-21 17:04:51 +00002666 LN0->getPointerInfo(), MemVT,
David Greene1e559442010-02-15 17:00:31 +00002667 LN0->isVolatile(), LN0->isNonTemporal(),
2668 LN0->getAlignment());
Chris Lattner5750df92006-03-01 04:03:14 +00002669 AddToWorkList(N);
Gabor Greifba36cb52008-08-28 21:40:38 +00002670 CombineTo(N0.getNode(), ExtLoad, ExtLoad.getValue(1));
Dan Gohman475871a2008-07-27 21:46:04 +00002671 return SDValue(N, 0); // Return N so it doesn't get rechecked!
Nate Begemanded49632005-10-13 03:11:28 +00002672 }
2673 }
Sylvestre Ledru94c22712012-09-27 10:14:43 +00002674 // fold (zext_inreg (sextload x)) -> (zextload x) iff load has one use
Gabor Greifba36cb52008-08-28 21:40:38 +00002675 if (ISD::isSEXTLoad(N0.getNode()) && ISD::isUNINDEXEDLoad(N0.getNode()) &&
Evan Cheng83060c52007-03-07 08:07:03 +00002676 N0.hasOneUse()) {
Evan Cheng466685d2006-10-09 20:57:25 +00002677 LoadSDNode *LN0 = cast<LoadSDNode>(N0);
Dan Gohman8a55ce42009-09-23 21:02:20 +00002678 EVT MemVT = LN0->getMemoryVT();
Nate Begemanbfd65a02005-10-13 18:34:58 +00002679 // If we zero all the possible extended bits, then we can turn this into
2680 // a zextload if we are running before legalize or the operation is legal.
Dan Gohman6900a392010-03-04 00:23:16 +00002681 unsigned BitWidth = N1.getValueType().getScalarType().getSizeInBits();
Dan Gohman2e68b6f2008-02-25 21:11:39 +00002682 if (DAG.MaskedValueIsZero(N1, APInt::getHighBitsSet(BitWidth,
Dan Gohman6900a392010-03-04 00:23:16 +00002683 BitWidth - MemVT.getScalarType().getSizeInBits())) &&
Duncan Sands25cf2272008-11-24 14:53:14 +00002684 ((!LegalOperations && !LN0->isVolatile()) ||
Dan Gohman8a55ce42009-09-23 21:02:20 +00002685 TLI.isLoadExtLegal(ISD::ZEXTLOAD, MemVT))) {
Stuart Hastingsa9011292011-02-16 16:23:55 +00002686 SDValue ExtLoad = DAG.getExtLoad(ISD::ZEXTLOAD, N0.getDebugLoc(), VT,
Bill Wendling2627a882009-01-30 20:43:18 +00002687 LN0->getChain(),
Chris Lattner3d6ccfb2010-09-21 17:04:51 +00002688 LN0->getBasePtr(), LN0->getPointerInfo(),
2689 MemVT,
David Greene1e559442010-02-15 17:00:31 +00002690 LN0->isVolatile(), LN0->isNonTemporal(),
2691 LN0->getAlignment());
Chris Lattner5750df92006-03-01 04:03:14 +00002692 AddToWorkList(N);
Gabor Greifba36cb52008-08-28 21:40:38 +00002693 CombineTo(N0.getNode(), ExtLoad, ExtLoad.getValue(1));
Dan Gohman475871a2008-07-27 21:46:04 +00002694 return SDValue(N, 0); // Return N so it doesn't get rechecked!
Nate Begemanded49632005-10-13 03:11:28 +00002695 }
2696 }
Scott Michelfdc40a02009-02-17 22:15:04 +00002697
Chris Lattner35a9f5a2006-02-28 06:49:37 +00002698 // fold (and (load x), 255) -> (zextload x, i8)
2699 // fold (and (extload x, i16), 255) -> (zextload x, i8)
Evan Chengd40d03e2010-01-06 19:38:29 +00002700 // fold (and (any_ext (extload x, i16)), 255) -> (zextload x, i8)
2701 if (N1C && (N0.getOpcode() == ISD::LOAD ||
2702 (N0.getOpcode() == ISD::ANY_EXTEND &&
2703 N0.getOperand(0).getOpcode() == ISD::LOAD))) {
2704 bool HasAnyExt = N0.getOpcode() == ISD::ANY_EXTEND;
2705 LoadSDNode *LN0 = HasAnyExt
2706 ? cast<LoadSDNode>(N0.getOperand(0))
2707 : cast<LoadSDNode>(N0);
Evan Cheng466685d2006-10-09 20:57:25 +00002708 if (LN0->getExtensionType() != ISD::SEXTLOAD &&
Chris Lattnerbd1fccf2010-01-07 21:59:23 +00002709 LN0->isUnindexed() && N0.hasOneUse() && LN0->hasOneUse()) {
Duncan Sands8eab8a22008-06-09 11:32:28 +00002710 uint32_t ActiveBits = N1C->getAPIntValue().getActiveBits();
Evan Chengd40d03e2010-01-06 19:38:29 +00002711 if (ActiveBits > 0 && APIntOps::isMask(ActiveBits, N1C->getAPIntValue())){
2712 EVT ExtVT = EVT::getIntegerVT(*DAG.getContext(), ActiveBits);
2713 EVT LoadedVT = LN0->getMemoryVT();
Duncan Sands8eab8a22008-06-09 11:32:28 +00002714
Evan Chengd40d03e2010-01-06 19:38:29 +00002715 if (ExtVT == LoadedVT &&
2716 (!LegalOperations || TLI.isLoadExtLegal(ISD::ZEXTLOAD, ExtVT))) {
Chris Lattneref7634c2010-01-07 21:53:27 +00002717 EVT LoadResultTy = HasAnyExt ? LN0->getValueType(0) : VT;
Wesley Peckbf17cfa2010-11-23 03:31:01 +00002718
2719 SDValue NewLoad =
Stuart Hastingsa9011292011-02-16 16:23:55 +00002720 DAG.getExtLoad(ISD::ZEXTLOAD, LN0->getDebugLoc(), LoadResultTy,
Chris Lattneref7634c2010-01-07 21:53:27 +00002721 LN0->getChain(), LN0->getBasePtr(),
Chris Lattner3d6ccfb2010-09-21 17:04:51 +00002722 LN0->getPointerInfo(),
David Greene1e559442010-02-15 17:00:31 +00002723 ExtVT, LN0->isVolatile(), LN0->isNonTemporal(),
2724 LN0->getAlignment());
Chris Lattneref7634c2010-01-07 21:53:27 +00002725 AddToWorkList(N);
2726 CombineTo(LN0, NewLoad, NewLoad.getValue(1));
2727 return SDValue(N, 0); // Return N so it doesn't get rechecked!
2728 }
Wesley Peckbf17cfa2010-11-23 03:31:01 +00002729
Chris Lattneref7634c2010-01-07 21:53:27 +00002730 // Do not change the width of a volatile load.
2731 // Do not generate loads of non-round integer types since these can
2732 // be expensive (and would be wrong if the type is not byte sized).
2733 if (!LN0->isVolatile() && LoadedVT.bitsGT(ExtVT) && ExtVT.isRound() &&
2734 (!LegalOperations || TLI.isLoadExtLegal(ISD::ZEXTLOAD, ExtVT))) {
2735 EVT PtrType = LN0->getOperand(1).getValueType();
Bill Wendling2627a882009-01-30 20:43:18 +00002736
Chris Lattneref7634c2010-01-07 21:53:27 +00002737 unsigned Alignment = LN0->getAlignment();
2738 SDValue NewPtr = LN0->getBasePtr();
2739
2740 // For big endian targets, we need to add an offset to the pointer
2741 // to load the correct bytes. For little endian systems, we merely
2742 // need to read fewer bytes from the same pointer.
2743 if (TLI.isBigEndian()) {
Evan Chengd40d03e2010-01-06 19:38:29 +00002744 unsigned LVTStoreBytes = LoadedVT.getStoreSize();
2745 unsigned EVTStoreBytes = ExtVT.getStoreSize();
2746 unsigned PtrOff = LVTStoreBytes - EVTStoreBytes;
Chris Lattneref7634c2010-01-07 21:53:27 +00002747 NewPtr = DAG.getNode(ISD::ADD, LN0->getDebugLoc(), PtrType,
2748 NewPtr, DAG.getConstant(PtrOff, PtrType));
2749 Alignment = MinAlign(Alignment, PtrOff);
Evan Chengd40d03e2010-01-06 19:38:29 +00002750 }
Chris Lattneref7634c2010-01-07 21:53:27 +00002751
2752 AddToWorkList(NewPtr.getNode());
Wesley Peckbf17cfa2010-11-23 03:31:01 +00002753
Chris Lattneref7634c2010-01-07 21:53:27 +00002754 EVT LoadResultTy = HasAnyExt ? LN0->getValueType(0) : VT;
2755 SDValue Load =
Stuart Hastingsa9011292011-02-16 16:23:55 +00002756 DAG.getExtLoad(ISD::ZEXTLOAD, LN0->getDebugLoc(), LoadResultTy,
Chris Lattneref7634c2010-01-07 21:53:27 +00002757 LN0->getChain(), NewPtr,
Chris Lattner3d6ccfb2010-09-21 17:04:51 +00002758 LN0->getPointerInfo(),
David Greene1e559442010-02-15 17:00:31 +00002759 ExtVT, LN0->isVolatile(), LN0->isNonTemporal(),
2760 Alignment);
Chris Lattneref7634c2010-01-07 21:53:27 +00002761 AddToWorkList(N);
2762 CombineTo(LN0, Load, Load.getValue(1));
2763 return SDValue(N, 0); // Return N so it doesn't get rechecked!
Duncan Sandsdc846502007-10-28 12:59:45 +00002764 }
Evan Cheng466685d2006-10-09 20:57:25 +00002765 }
Chris Lattner15045b62006-02-28 06:35:35 +00002766 }
2767 }
Scott Michelfdc40a02009-02-17 22:15:04 +00002768
Evan Chenga9e13ba2012-07-17 18:54:11 +00002769 if (N0.getOpcode() == ISD::ADD && N1.getOpcode() == ISD::SRL &&
2770 VT.getSizeInBits() <= 64) {
2771 if (ConstantSDNode *ADDI = dyn_cast<ConstantSDNode>(N0.getOperand(1))) {
2772 APInt ADDC = ADDI->getAPIntValue();
2773 if (!TLI.isLegalAddImmediate(ADDC.getSExtValue())) {
2774 // Look for (and (add x, c1), (lshr y, c2)). If C1 wasn't a legal
2775 // immediate for an add, but it is legal if its top c2 bits are set,
2776 // transform the ADD so the immediate doesn't need to be materialized
2777 // in a register.
2778 if (ConstantSDNode *SRLI = dyn_cast<ConstantSDNode>(N1.getOperand(1))) {
2779 APInt Mask = APInt::getHighBitsSet(VT.getSizeInBits(),
2780 SRLI->getZExtValue());
2781 if (DAG.MaskedValueIsZero(N0.getOperand(1), Mask)) {
2782 ADDC |= Mask;
2783 if (TLI.isLegalAddImmediate(ADDC.getSExtValue())) {
2784 SDValue NewAdd =
2785 DAG.getNode(ISD::ADD, N0.getDebugLoc(), VT,
2786 N0.getOperand(0), DAG.getConstant(ADDC, VT));
2787 CombineTo(N0.getNode(), NewAdd);
2788 return SDValue(N, 0); // Return N so it doesn't get rechecked!
2789 }
2790 }
2791 }
2792 }
2793 }
2794 }
Evan Chenga9e13ba2012-07-17 18:54:11 +00002795
Evan Chengb3a3d5e2010-04-28 07:10:39 +00002796 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00002797}
2798
Evan Cheng9568e5c2011-06-21 06:01:08 +00002799/// MatchBSwapHWord - Match (a >> 8) | (a << 8) as (bswap a) >> 16
2800///
2801SDValue DAGCombiner::MatchBSwapHWordLow(SDNode *N, SDValue N0, SDValue N1,
2802 bool DemandHighBits) {
2803 if (!LegalOperations)
2804 return SDValue();
2805
2806 EVT VT = N->getValueType(0);
2807 if (VT != MVT::i64 && VT != MVT::i32 && VT != MVT::i16)
2808 return SDValue();
2809 if (!TLI.isOperationLegal(ISD::BSWAP, VT))
2810 return SDValue();
2811
2812 // Recognize (and (shl a, 8), 0xff), (and (srl a, 8), 0xff00)
2813 bool LookPassAnd0 = false;
2814 bool LookPassAnd1 = false;
2815 if (N0.getOpcode() == ISD::AND && N0.getOperand(0).getOpcode() == ISD::SRL)
2816 std::swap(N0, N1);
2817 if (N1.getOpcode() == ISD::AND && N1.getOperand(0).getOpcode() == ISD::SHL)
2818 std::swap(N0, N1);
2819 if (N0.getOpcode() == ISD::AND) {
2820 if (!N0.getNode()->hasOneUse())
2821 return SDValue();
2822 ConstantSDNode *N01C = dyn_cast<ConstantSDNode>(N0.getOperand(1));
2823 if (!N01C || N01C->getZExtValue() != 0xFF00)
2824 return SDValue();
2825 N0 = N0.getOperand(0);
2826 LookPassAnd0 = true;
2827 }
2828
2829 if (N1.getOpcode() == ISD::AND) {
2830 if (!N1.getNode()->hasOneUse())
2831 return SDValue();
2832 ConstantSDNode *N11C = dyn_cast<ConstantSDNode>(N1.getOperand(1));
2833 if (!N11C || N11C->getZExtValue() != 0xFF)
2834 return SDValue();
2835 N1 = N1.getOperand(0);
2836 LookPassAnd1 = true;
2837 }
2838
2839 if (N0.getOpcode() == ISD::SRL && N1.getOpcode() == ISD::SHL)
2840 std::swap(N0, N1);
2841 if (N0.getOpcode() != ISD::SHL || N1.getOpcode() != ISD::SRL)
2842 return SDValue();
2843 if (!N0.getNode()->hasOneUse() ||
2844 !N1.getNode()->hasOneUse())
2845 return SDValue();
2846
2847 ConstantSDNode *N01C = dyn_cast<ConstantSDNode>(N0.getOperand(1));
2848 ConstantSDNode *N11C = dyn_cast<ConstantSDNode>(N1.getOperand(1));
2849 if (!N01C || !N11C)
2850 return SDValue();
2851 if (N01C->getZExtValue() != 8 || N11C->getZExtValue() != 8)
2852 return SDValue();
2853
2854 // Look for (shl (and a, 0xff), 8), (srl (and a, 0xff00), 8)
2855 SDValue N00 = N0->getOperand(0);
2856 if (!LookPassAnd0 && N00.getOpcode() == ISD::AND) {
2857 if (!N00.getNode()->hasOneUse())
2858 return SDValue();
2859 ConstantSDNode *N001C = dyn_cast<ConstantSDNode>(N00.getOperand(1));
2860 if (!N001C || N001C->getZExtValue() != 0xFF)
2861 return SDValue();
2862 N00 = N00.getOperand(0);
2863 LookPassAnd0 = true;
2864 }
2865
2866 SDValue N10 = N1->getOperand(0);
2867 if (!LookPassAnd1 && N10.getOpcode() == ISD::AND) {
2868 if (!N10.getNode()->hasOneUse())
2869 return SDValue();
2870 ConstantSDNode *N101C = dyn_cast<ConstantSDNode>(N10.getOperand(1));
2871 if (!N101C || N101C->getZExtValue() != 0xFF00)
2872 return SDValue();
2873 N10 = N10.getOperand(0);
2874 LookPassAnd1 = true;
2875 }
2876
2877 if (N00 != N10)
2878 return SDValue();
2879
2880 // Make sure everything beyond the low halfword is zero since the SRL 16
2881 // will clear the top bits.
2882 unsigned OpSizeInBits = VT.getSizeInBits();
2883 if (DemandHighBits && OpSizeInBits > 16 &&
2884 (!LookPassAnd0 || !LookPassAnd1) &&
2885 !DAG.MaskedValueIsZero(N10, APInt::getHighBitsSet(OpSizeInBits, 16)))
2886 return SDValue();
Eric Christopher7332e6e2011-07-14 01:12:15 +00002887
Evan Cheng9568e5c2011-06-21 06:01:08 +00002888 SDValue Res = DAG.getNode(ISD::BSWAP, N->getDebugLoc(), VT, N00);
2889 if (OpSizeInBits > 16)
2890 Res = DAG.getNode(ISD::SRL, N->getDebugLoc(), VT, Res,
2891 DAG.getConstant(OpSizeInBits-16, getShiftAmountTy(VT)));
2892 return Res;
2893}
2894
2895/// isBSwapHWordElement - Return true if the specified node is an element
2896/// that makes up a 32-bit packed halfword byteswap. i.e.
2897/// ((x&0xff)<<8)|((x&0xff00)>>8)|((x&0x00ff0000)<<8)|((x&0xff000000)>>8)
2898static bool isBSwapHWordElement(SDValue N, SmallVector<SDNode*,4> &Parts) {
2899 if (!N.getNode()->hasOneUse())
2900 return false;
2901
2902 unsigned Opc = N.getOpcode();
2903 if (Opc != ISD::AND && Opc != ISD::SHL && Opc != ISD::SRL)
2904 return false;
2905
2906 ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N.getOperand(1));
2907 if (!N1C)
2908 return false;
2909
2910 unsigned Num;
2911 switch (N1C->getZExtValue()) {
2912 default:
2913 return false;
2914 case 0xFF: Num = 0; break;
2915 case 0xFF00: Num = 1; break;
2916 case 0xFF0000: Num = 2; break;
2917 case 0xFF000000: Num = 3; break;
2918 }
2919
2920 // Look for (x & 0xff) << 8 as well as ((x << 8) & 0xff00).
2921 SDValue N0 = N.getOperand(0);
2922 if (Opc == ISD::AND) {
2923 if (Num == 0 || Num == 2) {
2924 // (x >> 8) & 0xff
2925 // (x >> 8) & 0xff0000
2926 if (N0.getOpcode() != ISD::SRL)
2927 return false;
2928 ConstantSDNode *C = dyn_cast<ConstantSDNode>(N0.getOperand(1));
2929 if (!C || C->getZExtValue() != 8)
2930 return false;
2931 } else {
2932 // (x << 8) & 0xff00
2933 // (x << 8) & 0xff000000
2934 if (N0.getOpcode() != ISD::SHL)
2935 return false;
2936 ConstantSDNode *C = dyn_cast<ConstantSDNode>(N0.getOperand(1));
2937 if (!C || C->getZExtValue() != 8)
2938 return false;
2939 }
2940 } else if (Opc == ISD::SHL) {
2941 // (x & 0xff) << 8
2942 // (x & 0xff0000) << 8
2943 if (Num != 0 && Num != 2)
2944 return false;
2945 ConstantSDNode *C = dyn_cast<ConstantSDNode>(N.getOperand(1));
2946 if (!C || C->getZExtValue() != 8)
2947 return false;
2948 } else { // Opc == ISD::SRL
2949 // (x & 0xff00) >> 8
2950 // (x & 0xff000000) >> 8
2951 if (Num != 1 && Num != 3)
2952 return false;
2953 ConstantSDNode *C = dyn_cast<ConstantSDNode>(N.getOperand(1));
2954 if (!C || C->getZExtValue() != 8)
2955 return false;
2956 }
2957
2958 if (Parts[Num])
2959 return false;
2960
2961 Parts[Num] = N0.getOperand(0).getNode();
2962 return true;
2963}
2964
2965/// MatchBSwapHWord - Match a 32-bit packed halfword bswap. That is
2966/// ((x&0xff)<<8)|((x&0xff00)>>8)|((x&0x00ff0000)<<8)|((x&0xff000000)>>8)
2967/// => (rotl (bswap x), 16)
2968SDValue DAGCombiner::MatchBSwapHWord(SDNode *N, SDValue N0, SDValue N1) {
2969 if (!LegalOperations)
2970 return SDValue();
2971
2972 EVT VT = N->getValueType(0);
2973 if (VT != MVT::i32)
2974 return SDValue();
2975 if (!TLI.isOperationLegal(ISD::BSWAP, VT))
2976 return SDValue();
2977
2978 SmallVector<SDNode*,4> Parts(4, (SDNode*)0);
2979 // Look for either
2980 // (or (or (and), (and)), (or (and), (and)))
2981 // (or (or (or (and), (and)), (and)), (and))
2982 if (N0.getOpcode() != ISD::OR)
2983 return SDValue();
2984 SDValue N00 = N0.getOperand(0);
2985 SDValue N01 = N0.getOperand(1);
2986
2987 if (N1.getOpcode() == ISD::OR) {
2988 // (or (or (and), (and)), (or (and), (and)))
2989 SDValue N000 = N00.getOperand(0);
2990 if (!isBSwapHWordElement(N000, Parts))
2991 return SDValue();
2992
2993 SDValue N001 = N00.getOperand(1);
2994 if (!isBSwapHWordElement(N001, Parts))
2995 return SDValue();
2996 SDValue N010 = N01.getOperand(0);
2997 if (!isBSwapHWordElement(N010, Parts))
2998 return SDValue();
2999 SDValue N011 = N01.getOperand(1);
3000 if (!isBSwapHWordElement(N011, Parts))
3001 return SDValue();
3002 } else {
3003 // (or (or (or (and), (and)), (and)), (and))
3004 if (!isBSwapHWordElement(N1, Parts))
3005 return SDValue();
3006 if (!isBSwapHWordElement(N01, Parts))
3007 return SDValue();
3008 if (N00.getOpcode() != ISD::OR)
3009 return SDValue();
3010 SDValue N000 = N00.getOperand(0);
3011 if (!isBSwapHWordElement(N000, Parts))
3012 return SDValue();
3013 SDValue N001 = N00.getOperand(1);
3014 if (!isBSwapHWordElement(N001, Parts))
3015 return SDValue();
3016 }
3017
3018 // Make sure the parts are all coming from the same node.
3019 if (Parts[0] != Parts[1] || Parts[0] != Parts[2] || Parts[0] != Parts[3])
3020 return SDValue();
3021
3022 SDValue BSwap = DAG.getNode(ISD::BSWAP, N->getDebugLoc(), VT,
3023 SDValue(Parts[0],0));
3024
3025 // Result of the bswap should be rotated by 16. If it's not legal, than
3026 // do (x << 16) | (x >> 16).
3027 SDValue ShAmt = DAG.getConstant(16, getShiftAmountTy(VT));
3028 if (TLI.isOperationLegalOrCustom(ISD::ROTL, VT))
3029 return DAG.getNode(ISD::ROTL, N->getDebugLoc(), VT, BSwap, ShAmt);
Craig Topper0eb5dad2012-09-29 07:18:53 +00003030 if (TLI.isOperationLegalOrCustom(ISD::ROTR, VT))
Evan Cheng9568e5c2011-06-21 06:01:08 +00003031 return DAG.getNode(ISD::ROTR, N->getDebugLoc(), VT, BSwap, ShAmt);
3032 return DAG.getNode(ISD::OR, N->getDebugLoc(), VT,
3033 DAG.getNode(ISD::SHL, N->getDebugLoc(), VT, BSwap, ShAmt),
3034 DAG.getNode(ISD::SRL, N->getDebugLoc(), VT, BSwap, ShAmt));
3035}
3036
Dan Gohman475871a2008-07-27 21:46:04 +00003037SDValue DAGCombiner::visitOR(SDNode *N) {
3038 SDValue N0 = N->getOperand(0);
3039 SDValue N1 = N->getOperand(1);
3040 SDValue LL, LR, RL, RR, CC0, CC1;
Nate Begeman646d7e22005-09-02 21:18:40 +00003041 ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0);
3042 ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1);
Owen Andersone50ed302009-08-10 22:56:29 +00003043 EVT VT = N1.getValueType();
Scott Michelfdc40a02009-02-17 22:15:04 +00003044
Dan Gohman7f321562007-06-25 16:23:39 +00003045 // fold vector ops
Duncan Sands83ec4b62008-06-06 12:08:01 +00003046 if (VT.isVector()) {
Dan Gohman475871a2008-07-27 21:46:04 +00003047 SDValue FoldedVOp = SimplifyVBinOp(N);
Gabor Greifba36cb52008-08-28 21:40:38 +00003048 if (FoldedVOp.getNode()) return FoldedVOp;
Craig Topper9472b4f2012-12-08 22:49:19 +00003049
3050 // fold (or x, 0) -> x, vector edition
3051 if (ISD::isBuildVectorAllZeros(N0.getNode()))
3052 return N1;
3053 if (ISD::isBuildVectorAllZeros(N1.getNode()))
3054 return N0;
3055
3056 // fold (or x, -1) -> -1, vector edition
3057 if (ISD::isBuildVectorAllOnes(N0.getNode()))
3058 return N0;
3059 if (ISD::isBuildVectorAllOnes(N1.getNode()))
3060 return N1;
Dan Gohman05d92fe2007-07-13 20:03:40 +00003061 }
Scott Michelfdc40a02009-02-17 22:15:04 +00003062
Dan Gohman613e0d82007-07-03 14:03:57 +00003063 // fold (or x, undef) -> -1
Bob Wilson86749492010-06-28 23:40:25 +00003064 if (!LegalOperations &&
3065 (N0.getOpcode() == ISD::UNDEF || N1.getOpcode() == ISD::UNDEF)) {
Nate Begeman93e0ed32009-12-03 07:11:29 +00003066 EVT EltVT = VT.isVector() ? VT.getVectorElementType() : VT;
3067 return DAG.getConstant(APInt::getAllOnesValue(EltVT.getSizeInBits()), VT);
3068 }
Nate Begeman1d4d4142005-09-01 00:19:25 +00003069 // fold (or c1, c2) -> c1|c2
Nate Begeman646d7e22005-09-02 21:18:40 +00003070 if (N0C && N1C)
Bill Wendlingf3cbca22008-09-24 10:25:02 +00003071 return DAG.FoldConstantArithmetic(ISD::OR, VT, N0C, N1C);
Nate Begeman99801192005-09-07 23:25:52 +00003072 // canonicalize constant to RHS
Nate Begemana0e221d2005-10-18 00:28:13 +00003073 if (N0C && !N1C)
Bill Wendling09025642009-01-30 20:59:34 +00003074 return DAG.getNode(ISD::OR, N->getDebugLoc(), VT, N1, N0);
Nate Begeman1d4d4142005-09-01 00:19:25 +00003075 // fold (or x, 0) -> x
Nate Begeman646d7e22005-09-02 21:18:40 +00003076 if (N1C && N1C->isNullValue())
Nate Begeman83e75ec2005-09-06 04:43:02 +00003077 return N0;
Nate Begeman1d4d4142005-09-01 00:19:25 +00003078 // fold (or x, -1) -> -1
Nate Begeman646d7e22005-09-02 21:18:40 +00003079 if (N1C && N1C->isAllOnesValue())
Nate Begeman83e75ec2005-09-06 04:43:02 +00003080 return N1;
Sylvestre Ledru94c22712012-09-27 10:14:43 +00003081 // fold (or x, c) -> c iff (x & ~c) == 0
Dan Gohman2e68b6f2008-02-25 21:11:39 +00003082 if (N1C && DAG.MaskedValueIsZero(N0, ~N1C->getAPIntValue()))
Nate Begeman83e75ec2005-09-06 04:43:02 +00003083 return N1;
Evan Cheng9568e5c2011-06-21 06:01:08 +00003084
3085 // Recognize halfword bswaps as (bswap + rotl 16) or (bswap + shl 16)
3086 SDValue BSwap = MatchBSwapHWord(N, N0, N1);
3087 if (BSwap.getNode() != 0)
3088 return BSwap;
3089 BSwap = MatchBSwapHWordLow(N, N0, N1);
3090 if (BSwap.getNode() != 0)
3091 return BSwap;
3092
Nate Begemancd4d58c2006-02-03 06:46:56 +00003093 // reassociate or
Bill Wendling35247c32009-01-30 00:45:56 +00003094 SDValue ROR = ReassociateOps(ISD::OR, N->getDebugLoc(), N0, N1);
Gabor Greifba36cb52008-08-28 21:40:38 +00003095 if (ROR.getNode() != 0)
Nate Begemancd4d58c2006-02-03 06:46:56 +00003096 return ROR;
3097 // Canonicalize (or (and X, c1), c2) -> (and (or X, c2), c1|c2)
Sylvestre Ledru94c22712012-09-27 10:14:43 +00003098 // iff (c1 & c2) == 0.
Gabor Greifba36cb52008-08-28 21:40:38 +00003099 if (N1C && N0.getOpcode() == ISD::AND && N0.getNode()->hasOneUse() &&
Chris Lattner731d3482005-10-27 05:06:38 +00003100 isa<ConstantSDNode>(N0.getOperand(1))) {
Chris Lattner731d3482005-10-27 05:06:38 +00003101 ConstantSDNode *C1 = cast<ConstantSDNode>(N0.getOperand(1));
Bill Wendling32f9eb22010-03-03 01:58:01 +00003102 if ((C1->getAPIntValue() & N1C->getAPIntValue()) != 0)
Bill Wendling7d9f2b92010-03-03 00:35:56 +00003103 return DAG.getNode(ISD::AND, N->getDebugLoc(), VT,
3104 DAG.getNode(ISD::OR, N0.getDebugLoc(), VT,
3105 N0.getOperand(0), N1),
3106 DAG.FoldConstantArithmetic(ISD::OR, VT, N1C, C1));
Nate Begeman223df222005-09-08 20:18:10 +00003107 }
Nate Begeman39ee1ac2005-09-09 19:49:52 +00003108 // fold (or (setcc x), (setcc y)) -> (setcc (or x, y))
3109 if (isSetCCEquivalent(N0, LL, LR, CC0) && isSetCCEquivalent(N1, RL, RR, CC1)){
3110 ISD::CondCode Op0 = cast<CondCodeSDNode>(CC0)->get();
3111 ISD::CondCode Op1 = cast<CondCodeSDNode>(CC1)->get();
Scott Michelfdc40a02009-02-17 22:15:04 +00003112
Nate Begeman39ee1ac2005-09-09 19:49:52 +00003113 if (LR == RR && isa<ConstantSDNode>(LR) && Op0 == Op1 &&
Duncan Sands83ec4b62008-06-06 12:08:01 +00003114 LL.getValueType().isInteger()) {
Bill Wendling09025642009-01-30 20:59:34 +00003115 // fold (or (setne X, 0), (setne Y, 0)) -> (setne (or X, Y), 0)
3116 // fold (or (setlt X, 0), (setlt Y, 0)) -> (setne (or X, Y), 0)
Scott Michelfdc40a02009-02-17 22:15:04 +00003117 if (cast<ConstantSDNode>(LR)->isNullValue() &&
Nate Begeman39ee1ac2005-09-09 19:49:52 +00003118 (Op1 == ISD::SETNE || Op1 == ISD::SETLT)) {
Bill Wendling09025642009-01-30 20:59:34 +00003119 SDValue ORNode = DAG.getNode(ISD::OR, LR.getDebugLoc(),
3120 LR.getValueType(), LL, RL);
Gabor Greifba36cb52008-08-28 21:40:38 +00003121 AddToWorkList(ORNode.getNode());
Bill Wendling09025642009-01-30 20:59:34 +00003122 return DAG.getSetCC(N->getDebugLoc(), VT, ORNode, LR, Op1);
Nate Begeman39ee1ac2005-09-09 19:49:52 +00003123 }
Bill Wendling09025642009-01-30 20:59:34 +00003124 // fold (or (setne X, -1), (setne Y, -1)) -> (setne (and X, Y), -1)
3125 // fold (or (setgt X, -1), (setgt Y -1)) -> (setgt (and X, Y), -1)
Scott Michelfdc40a02009-02-17 22:15:04 +00003126 if (cast<ConstantSDNode>(LR)->isAllOnesValue() &&
Nate Begeman39ee1ac2005-09-09 19:49:52 +00003127 (Op1 == ISD::SETNE || Op1 == ISD::SETGT)) {
Bill Wendling09025642009-01-30 20:59:34 +00003128 SDValue ANDNode = DAG.getNode(ISD::AND, LR.getDebugLoc(),
3129 LR.getValueType(), LL, RL);
Gabor Greifba36cb52008-08-28 21:40:38 +00003130 AddToWorkList(ANDNode.getNode());
Bill Wendling09025642009-01-30 20:59:34 +00003131 return DAG.getSetCC(N->getDebugLoc(), VT, ANDNode, LR, Op1);
Nate Begeman39ee1ac2005-09-09 19:49:52 +00003132 }
3133 }
3134 // canonicalize equivalent to ll == rl
3135 if (LL == RR && LR == RL) {
3136 Op1 = ISD::getSetCCSwappedOperands(Op1);
3137 std::swap(RL, RR);
3138 }
3139 if (LL == RL && LR == RR) {
Duncan Sands83ec4b62008-06-06 12:08:01 +00003140 bool isInteger = LL.getValueType().isInteger();
Nate Begeman39ee1ac2005-09-09 19:49:52 +00003141 ISD::CondCode Result = ISD::getSetCCOrOperation(Op0, Op1, isInteger);
Chris Lattner6e1c6232008-10-28 07:11:07 +00003142 if (Result != ISD::SETCC_INVALID &&
Patrik Hagglund34525f92012-12-11 11:14:33 +00003143 (!LegalOperations || TLI.isCondCodeLegal(Result, LL.getValueType())))
Bill Wendling09025642009-01-30 20:59:34 +00003144 return DAG.getSetCC(N->getDebugLoc(), N0.getValueType(),
3145 LL, LR, Result);
Nate Begeman39ee1ac2005-09-09 19:49:52 +00003146 }
3147 }
Scott Michelfdc40a02009-02-17 22:15:04 +00003148
Bill Wendling09025642009-01-30 20:59:34 +00003149 // Simplify: (or (op x...), (op y...)) -> (op (or x, y))
Chris Lattner35e5c142006-05-05 05:51:50 +00003150 if (N0.getOpcode() == N1.getOpcode()) {
Dan Gohman475871a2008-07-27 21:46:04 +00003151 SDValue Tmp = SimplifyBinOpWithSameOpcodeHands(N);
Gabor Greifba36cb52008-08-28 21:40:38 +00003152 if (Tmp.getNode()) return Tmp;
Nate Begeman39ee1ac2005-09-09 19:49:52 +00003153 }
Scott Michelfdc40a02009-02-17 22:15:04 +00003154
Bill Wendling09025642009-01-30 20:59:34 +00003155 // (or (and X, C1), (and Y, C2)) -> (and (or X, Y), C3) if possible.
Chris Lattner1ec72732006-09-14 21:11:37 +00003156 if (N0.getOpcode() == ISD::AND &&
3157 N1.getOpcode() == ISD::AND &&
3158 N0.getOperand(1).getOpcode() == ISD::Constant &&
3159 N1.getOperand(1).getOpcode() == ISD::Constant &&
3160 // Don't increase # computations.
Gabor Greifba36cb52008-08-28 21:40:38 +00003161 (N0.getNode()->hasOneUse() || N1.getNode()->hasOneUse())) {
Chris Lattner1ec72732006-09-14 21:11:37 +00003162 // We can only do this xform if we know that bits from X that are set in C2
3163 // but not in C1 are already zero. Likewise for Y.
Dan Gohman2e68b6f2008-02-25 21:11:39 +00003164 const APInt &LHSMask =
3165 cast<ConstantSDNode>(N0.getOperand(1))->getAPIntValue();
3166 const APInt &RHSMask =
3167 cast<ConstantSDNode>(N1.getOperand(1))->getAPIntValue();
Scott Michelfdc40a02009-02-17 22:15:04 +00003168
Dan Gohmanea859be2007-06-22 14:59:07 +00003169 if (DAG.MaskedValueIsZero(N0.getOperand(0), RHSMask&~LHSMask) &&
3170 DAG.MaskedValueIsZero(N1.getOperand(0), LHSMask&~RHSMask)) {
Bill Wendling09025642009-01-30 20:59:34 +00003171 SDValue X = DAG.getNode(ISD::OR, N0.getDebugLoc(), VT,
3172 N0.getOperand(0), N1.getOperand(0));
3173 return DAG.getNode(ISD::AND, N->getDebugLoc(), VT, X,
3174 DAG.getConstant(LHSMask | RHSMask, VT));
Chris Lattner1ec72732006-09-14 21:11:37 +00003175 }
3176 }
Scott Michelfdc40a02009-02-17 22:15:04 +00003177
Chris Lattner516b9622006-09-14 20:50:57 +00003178 // See if this is some rotate idiom.
Bill Wendling317bd702009-01-30 21:14:50 +00003179 if (SDNode *Rot = MatchRotate(N0, N1, N->getDebugLoc()))
Dan Gohman475871a2008-07-27 21:46:04 +00003180 return SDValue(Rot, 0);
Chris Lattner35e5c142006-05-05 05:51:50 +00003181
Dan Gohman4e39e9d2010-06-24 14:30:44 +00003182 // Simplify the operands using demanded-bits information.
3183 if (!VT.isVector() &&
3184 SimplifyDemandedBits(SDValue(N, 0)))
3185 return SDValue(N, 0);
3186
Evan Chengb3a3d5e2010-04-28 07:10:39 +00003187 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00003188}
3189
Chris Lattner516b9622006-09-14 20:50:57 +00003190/// MatchRotateHalf - Match "(X shl/srl V1) & V2" where V2 may not be present.
Dan Gohman475871a2008-07-27 21:46:04 +00003191static bool MatchRotateHalf(SDValue Op, SDValue &Shift, SDValue &Mask) {
Chris Lattner516b9622006-09-14 20:50:57 +00003192 if (Op.getOpcode() == ISD::AND) {
Reid Spencer3ed469c2006-11-02 20:25:50 +00003193 if (isa<ConstantSDNode>(Op.getOperand(1))) {
Chris Lattner516b9622006-09-14 20:50:57 +00003194 Mask = Op.getOperand(1);
3195 Op = Op.getOperand(0);
3196 } else {
3197 return false;
3198 }
3199 }
Scott Michelfdc40a02009-02-17 22:15:04 +00003200
Chris Lattner516b9622006-09-14 20:50:57 +00003201 if (Op.getOpcode() == ISD::SRL || Op.getOpcode() == ISD::SHL) {
3202 Shift = Op;
3203 return true;
3204 }
Bill Wendling09025642009-01-30 20:59:34 +00003205
Scott Michelfdc40a02009-02-17 22:15:04 +00003206 return false;
Chris Lattner516b9622006-09-14 20:50:57 +00003207}
3208
Chris Lattner516b9622006-09-14 20:50:57 +00003209// MatchRotate - Handle an 'or' of two operands. If this is one of the many
3210// idioms for rotate, and if the target supports rotation instructions, generate
3211// a rot[lr].
Bill Wendling317bd702009-01-30 21:14:50 +00003212SDNode *DAGCombiner::MatchRotate(SDValue LHS, SDValue RHS, DebugLoc DL) {
Duncan Sandsd4b9c172008-06-13 19:07:40 +00003213 // Must be a legal type. Expanded 'n promoted things won't work with rotates.
Owen Andersone50ed302009-08-10 22:56:29 +00003214 EVT VT = LHS.getValueType();
Chris Lattner516b9622006-09-14 20:50:57 +00003215 if (!TLI.isTypeLegal(VT)) return 0;
3216
3217 // The target must have at least one rotate flavor.
Dan Gohmanf560ffa2009-01-28 17:46:25 +00003218 bool HasROTL = TLI.isOperationLegalOrCustom(ISD::ROTL, VT);
3219 bool HasROTR = TLI.isOperationLegalOrCustom(ISD::ROTR, VT);
Chris Lattner516b9622006-09-14 20:50:57 +00003220 if (!HasROTL && !HasROTR) return 0;
Duncan Sandsd4b9c172008-06-13 19:07:40 +00003221
Chris Lattner516b9622006-09-14 20:50:57 +00003222 // Match "(X shl/srl V1) & V2" where V2 may not be present.
Dan Gohman475871a2008-07-27 21:46:04 +00003223 SDValue LHSShift; // The shift.
3224 SDValue LHSMask; // AND value if any.
Chris Lattner516b9622006-09-14 20:50:57 +00003225 if (!MatchRotateHalf(LHS, LHSShift, LHSMask))
3226 return 0; // Not part of a rotate.
3227
Dan Gohman475871a2008-07-27 21:46:04 +00003228 SDValue RHSShift; // The shift.
3229 SDValue RHSMask; // AND value if any.
Chris Lattner516b9622006-09-14 20:50:57 +00003230 if (!MatchRotateHalf(RHS, RHSShift, RHSMask))
3231 return 0; // Not part of a rotate.
Scott Michelfdc40a02009-02-17 22:15:04 +00003232
Chris Lattner516b9622006-09-14 20:50:57 +00003233 if (LHSShift.getOperand(0) != RHSShift.getOperand(0))
3234 return 0; // Not shifting the same value.
3235
3236 if (LHSShift.getOpcode() == RHSShift.getOpcode())
3237 return 0; // Shifts must disagree.
Scott Michelfdc40a02009-02-17 22:15:04 +00003238
Chris Lattner516b9622006-09-14 20:50:57 +00003239 // Canonicalize shl to left side in a shl/srl pair.
3240 if (RHSShift.getOpcode() == ISD::SHL) {
3241 std::swap(LHS, RHS);
3242 std::swap(LHSShift, RHSShift);
3243 std::swap(LHSMask , RHSMask );
3244 }
3245
Duncan Sands83ec4b62008-06-06 12:08:01 +00003246 unsigned OpSizeInBits = VT.getSizeInBits();
Dan Gohman475871a2008-07-27 21:46:04 +00003247 SDValue LHSShiftArg = LHSShift.getOperand(0);
3248 SDValue LHSShiftAmt = LHSShift.getOperand(1);
3249 SDValue RHSShiftAmt = RHSShift.getOperand(1);
Chris Lattner516b9622006-09-14 20:50:57 +00003250
3251 // fold (or (shl x, C1), (srl x, C2)) -> (rotl x, C1)
3252 // fold (or (shl x, C1), (srl x, C2)) -> (rotr x, C2)
Scott Michelc9dc1142007-04-02 21:36:32 +00003253 if (LHSShiftAmt.getOpcode() == ISD::Constant &&
3254 RHSShiftAmt.getOpcode() == ISD::Constant) {
Dan Gohmanf5aeb1a2008-09-12 16:56:44 +00003255 uint64_t LShVal = cast<ConstantSDNode>(LHSShiftAmt)->getZExtValue();
3256 uint64_t RShVal = cast<ConstantSDNode>(RHSShiftAmt)->getZExtValue();
Chris Lattner516b9622006-09-14 20:50:57 +00003257 if ((LShVal + RShVal) != OpSizeInBits)
3258 return 0;
3259
Craig Topper32b73432012-09-29 06:54:22 +00003260 SDValue Rot = DAG.getNode(HasROTL ? ISD::ROTL : ISD::ROTR, DL, VT,
3261 LHSShiftArg, HasROTL ? LHSShiftAmt : RHSShiftAmt);
Scott Michelfdc40a02009-02-17 22:15:04 +00003262
Chris Lattner516b9622006-09-14 20:50:57 +00003263 // If there is an AND of either shifted operand, apply it to the result.
Gabor Greifba36cb52008-08-28 21:40:38 +00003264 if (LHSMask.getNode() || RHSMask.getNode()) {
Dan Gohman220a8232008-03-03 23:51:38 +00003265 APInt Mask = APInt::getAllOnesValue(OpSizeInBits);
Scott Michelfdc40a02009-02-17 22:15:04 +00003266
Gabor Greifba36cb52008-08-28 21:40:38 +00003267 if (LHSMask.getNode()) {
Dan Gohman220a8232008-03-03 23:51:38 +00003268 APInt RHSBits = APInt::getLowBitsSet(OpSizeInBits, LShVal);
3269 Mask &= cast<ConstantSDNode>(LHSMask)->getAPIntValue() | RHSBits;
Chris Lattner516b9622006-09-14 20:50:57 +00003270 }
Gabor Greifba36cb52008-08-28 21:40:38 +00003271 if (RHSMask.getNode()) {
Dan Gohman220a8232008-03-03 23:51:38 +00003272 APInt LHSBits = APInt::getHighBitsSet(OpSizeInBits, RShVal);
3273 Mask &= cast<ConstantSDNode>(RHSMask)->getAPIntValue() | LHSBits;
Chris Lattner516b9622006-09-14 20:50:57 +00003274 }
Scott Michelfdc40a02009-02-17 22:15:04 +00003275
Bill Wendling317bd702009-01-30 21:14:50 +00003276 Rot = DAG.getNode(ISD::AND, DL, VT, Rot, DAG.getConstant(Mask, VT));
Chris Lattner516b9622006-09-14 20:50:57 +00003277 }
Scott Michelfdc40a02009-02-17 22:15:04 +00003278
Gabor Greifba36cb52008-08-28 21:40:38 +00003279 return Rot.getNode();
Chris Lattner516b9622006-09-14 20:50:57 +00003280 }
Scott Michelfdc40a02009-02-17 22:15:04 +00003281
Chris Lattner516b9622006-09-14 20:50:57 +00003282 // If there is a mask here, and we have a variable shift, we can't be sure
3283 // that we're masking out the right stuff.
Gabor Greifba36cb52008-08-28 21:40:38 +00003284 if (LHSMask.getNode() || RHSMask.getNode())
Chris Lattner516b9622006-09-14 20:50:57 +00003285 return 0;
Scott Michelfdc40a02009-02-17 22:15:04 +00003286
Chris Lattner516b9622006-09-14 20:50:57 +00003287 // fold (or (shl x, y), (srl x, (sub 32, y))) -> (rotl x, y)
3288 // fold (or (shl x, y), (srl x, (sub 32, y))) -> (rotr x, (sub 32, y))
Scott Michelc9dc1142007-04-02 21:36:32 +00003289 if (RHSShiftAmt.getOpcode() == ISD::SUB &&
3290 LHSShiftAmt == RHSShiftAmt.getOperand(1)) {
Scott Michelfdc40a02009-02-17 22:15:04 +00003291 if (ConstantSDNode *SUBC =
Scott Michelc9dc1142007-04-02 21:36:32 +00003292 dyn_cast<ConstantSDNode>(RHSShiftAmt.getOperand(0))) {
Dan Gohman002e5d02008-03-13 22:13:53 +00003293 if (SUBC->getAPIntValue() == OpSizeInBits) {
Craig Topper32b73432012-09-29 06:54:22 +00003294 return DAG.getNode(HasROTL ? ISD::ROTL : ISD::ROTR, DL, VT, LHSShiftArg,
3295 HasROTL ? LHSShiftAmt : RHSShiftAmt).getNode();
Anton Korobeynikov4c71dfe2008-02-20 11:10:28 +00003296 }
Chris Lattner516b9622006-09-14 20:50:57 +00003297 }
3298 }
Scott Michelfdc40a02009-02-17 22:15:04 +00003299
Chris Lattner516b9622006-09-14 20:50:57 +00003300 // fold (or (shl x, (sub 32, y)), (srl x, r)) -> (rotr x, y)
3301 // fold (or (shl x, (sub 32, y)), (srl x, r)) -> (rotl x, (sub 32, y))
Scott Michelc9dc1142007-04-02 21:36:32 +00003302 if (LHSShiftAmt.getOpcode() == ISD::SUB &&
3303 RHSShiftAmt == LHSShiftAmt.getOperand(1)) {
Scott Michelfdc40a02009-02-17 22:15:04 +00003304 if (ConstantSDNode *SUBC =
Scott Michelc9dc1142007-04-02 21:36:32 +00003305 dyn_cast<ConstantSDNode>(LHSShiftAmt.getOperand(0))) {
Dan Gohman002e5d02008-03-13 22:13:53 +00003306 if (SUBC->getAPIntValue() == OpSizeInBits) {
Craig Topper32b73432012-09-29 06:54:22 +00003307 return DAG.getNode(HasROTR ? ISD::ROTR : ISD::ROTL, DL, VT, LHSShiftArg,
3308 HasROTR ? RHSShiftAmt : LHSShiftAmt).getNode();
Anton Korobeynikov4c71dfe2008-02-20 11:10:28 +00003309 }
Scott Michelc9dc1142007-04-02 21:36:32 +00003310 }
3311 }
3312
Dan Gohman74feef22008-10-17 01:23:35 +00003313 // Look for sign/zext/any-extended or truncate cases:
Craig Topper0eb5dad2012-09-29 07:18:53 +00003314 if ((LHSShiftAmt.getOpcode() == ISD::SIGN_EXTEND ||
3315 LHSShiftAmt.getOpcode() == ISD::ZERO_EXTEND ||
3316 LHSShiftAmt.getOpcode() == ISD::ANY_EXTEND ||
3317 LHSShiftAmt.getOpcode() == ISD::TRUNCATE) &&
3318 (RHSShiftAmt.getOpcode() == ISD::SIGN_EXTEND ||
3319 RHSShiftAmt.getOpcode() == ISD::ZERO_EXTEND ||
3320 RHSShiftAmt.getOpcode() == ISD::ANY_EXTEND ||
3321 RHSShiftAmt.getOpcode() == ISD::TRUNCATE)) {
Dan Gohman475871a2008-07-27 21:46:04 +00003322 SDValue LExtOp0 = LHSShiftAmt.getOperand(0);
3323 SDValue RExtOp0 = RHSShiftAmt.getOperand(0);
Scott Michelc9dc1142007-04-02 21:36:32 +00003324 if (RExtOp0.getOpcode() == ISD::SUB &&
3325 RExtOp0.getOperand(1) == LExtOp0) {
3326 // fold (or (shl x, (*ext y)), (srl x, (*ext (sub 32, y)))) ->
Bill Wendlingc5cbda12008-08-31 00:37:27 +00003327 // (rotl x, y)
Scott Michelc9dc1142007-04-02 21:36:32 +00003328 // fold (or (shl x, (*ext y)), (srl x, (*ext (sub 32, y)))) ->
Bill Wendlingc5cbda12008-08-31 00:37:27 +00003329 // (rotr x, (sub 32, y))
Dan Gohman74feef22008-10-17 01:23:35 +00003330 if (ConstantSDNode *SUBC =
3331 dyn_cast<ConstantSDNode>(RExtOp0.getOperand(0))) {
Dan Gohman002e5d02008-03-13 22:13:53 +00003332 if (SUBC->getAPIntValue() == OpSizeInBits) {
Bill Wendling317bd702009-01-30 21:14:50 +00003333 return DAG.getNode(HasROTL ? ISD::ROTL : ISD::ROTR, DL, VT,
3334 LHSShiftArg,
Gabor Greif12632d22008-08-30 19:29:20 +00003335 HasROTL ? LHSShiftAmt : RHSShiftAmt).getNode();
Scott Michelc9dc1142007-04-02 21:36:32 +00003336 }
3337 }
3338 } else if (LExtOp0.getOpcode() == ISD::SUB &&
3339 RExtOp0 == LExtOp0.getOperand(1)) {
Scott Michelfdc40a02009-02-17 22:15:04 +00003340 // fold (or (shl x, (*ext (sub 32, y))), (srl x, (*ext y))) ->
Bill Wendlingc5cbda12008-08-31 00:37:27 +00003341 // (rotr x, y)
Bill Wendling353dea22008-08-31 01:04:56 +00003342 // fold (or (shl x, (*ext (sub 32, y))), (srl x, (*ext y))) ->
Bill Wendlingc5cbda12008-08-31 00:37:27 +00003343 // (rotl x, (sub 32, y))
Dan Gohman74feef22008-10-17 01:23:35 +00003344 if (ConstantSDNode *SUBC =
3345 dyn_cast<ConstantSDNode>(LExtOp0.getOperand(0))) {
Dan Gohman002e5d02008-03-13 22:13:53 +00003346 if (SUBC->getAPIntValue() == OpSizeInBits) {
Bill Wendling317bd702009-01-30 21:14:50 +00003347 return DAG.getNode(HasROTR ? ISD::ROTR : ISD::ROTL, DL, VT,
3348 LHSShiftArg,
Bill Wendling353dea22008-08-31 01:04:56 +00003349 HasROTR ? RHSShiftAmt : LHSShiftAmt).getNode();
Scott Michelc9dc1142007-04-02 21:36:32 +00003350 }
3351 }
Chris Lattner516b9622006-09-14 20:50:57 +00003352 }
3353 }
Scott Michelfdc40a02009-02-17 22:15:04 +00003354
Chris Lattner516b9622006-09-14 20:50:57 +00003355 return 0;
3356}
3357
Dan Gohman475871a2008-07-27 21:46:04 +00003358SDValue DAGCombiner::visitXOR(SDNode *N) {
3359 SDValue N0 = N->getOperand(0);
3360 SDValue N1 = N->getOperand(1);
3361 SDValue LHS, RHS, CC;
Nate Begeman646d7e22005-09-02 21:18:40 +00003362 ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0);
3363 ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1);
Owen Andersone50ed302009-08-10 22:56:29 +00003364 EVT VT = N0.getValueType();
Scott Michelfdc40a02009-02-17 22:15:04 +00003365
Dan Gohman7f321562007-06-25 16:23:39 +00003366 // fold vector ops
Duncan Sands83ec4b62008-06-06 12:08:01 +00003367 if (VT.isVector()) {
Dan Gohman475871a2008-07-27 21:46:04 +00003368 SDValue FoldedVOp = SimplifyVBinOp(N);
Gabor Greifba36cb52008-08-28 21:40:38 +00003369 if (FoldedVOp.getNode()) return FoldedVOp;
Craig Topper9472b4f2012-12-08 22:49:19 +00003370
3371 // fold (xor x, 0) -> x, vector edition
3372 if (ISD::isBuildVectorAllZeros(N0.getNode()))
3373 return N1;
3374 if (ISD::isBuildVectorAllZeros(N1.getNode()))
3375 return N0;
Dan Gohman05d92fe2007-07-13 20:03:40 +00003376 }
Scott Michelfdc40a02009-02-17 22:15:04 +00003377
Evan Cheng26471c42008-03-25 20:08:07 +00003378 // fold (xor undef, undef) -> 0. This is a common idiom (misuse).
3379 if (N0.getOpcode() == ISD::UNDEF && N1.getOpcode() == ISD::UNDEF)
3380 return DAG.getConstant(0, VT);
Dan Gohman613e0d82007-07-03 14:03:57 +00003381 // fold (xor x, undef) -> undef
Dan Gohman70fb1ae2007-07-10 15:19:29 +00003382 if (N0.getOpcode() == ISD::UNDEF)
3383 return N0;
3384 if (N1.getOpcode() == ISD::UNDEF)
Dan Gohman613e0d82007-07-03 14:03:57 +00003385 return N1;
Nate Begeman1d4d4142005-09-01 00:19:25 +00003386 // fold (xor c1, c2) -> c1^c2
Nate Begeman646d7e22005-09-02 21:18:40 +00003387 if (N0C && N1C)
Bill Wendlingf3cbca22008-09-24 10:25:02 +00003388 return DAG.FoldConstantArithmetic(ISD::XOR, VT, N0C, N1C);
Nate Begeman99801192005-09-07 23:25:52 +00003389 // canonicalize constant to RHS
Nate Begemana0e221d2005-10-18 00:28:13 +00003390 if (N0C && !N1C)
Bill Wendling317bd702009-01-30 21:14:50 +00003391 return DAG.getNode(ISD::XOR, N->getDebugLoc(), VT, N1, N0);
Nate Begeman1d4d4142005-09-01 00:19:25 +00003392 // fold (xor x, 0) -> x
Nate Begeman646d7e22005-09-02 21:18:40 +00003393 if (N1C && N1C->isNullValue())
Nate Begeman83e75ec2005-09-06 04:43:02 +00003394 return N0;
Nate Begemancd4d58c2006-02-03 06:46:56 +00003395 // reassociate xor
Bill Wendling35247c32009-01-30 00:45:56 +00003396 SDValue RXOR = ReassociateOps(ISD::XOR, N->getDebugLoc(), N0, N1);
Gabor Greifba36cb52008-08-28 21:40:38 +00003397 if (RXOR.getNode() != 0)
Nate Begemancd4d58c2006-02-03 06:46:56 +00003398 return RXOR;
Bill Wendlingae89bb12008-11-11 08:25:46 +00003399
Nate Begeman1d4d4142005-09-01 00:19:25 +00003400 // fold !(x cc y) -> (x !cc y)
Dan Gohman002e5d02008-03-13 22:13:53 +00003401 if (N1C && N1C->getAPIntValue() == 1 && isSetCCEquivalent(N0, LHS, RHS, CC)) {
Duncan Sands83ec4b62008-06-06 12:08:01 +00003402 bool isInt = LHS.getValueType().isInteger();
Nate Begeman646d7e22005-09-02 21:18:40 +00003403 ISD::CondCode NotCC = ISD::getSetCCInverse(cast<CondCodeSDNode>(CC)->get(),
3404 isInt);
Bill Wendlingae89bb12008-11-11 08:25:46 +00003405
Patrik Hagglund34525f92012-12-11 11:14:33 +00003406 if (!LegalOperations || TLI.isCondCodeLegal(NotCC, LHS.getValueType())) {
Bill Wendlingae89bb12008-11-11 08:25:46 +00003407 switch (N0.getOpcode()) {
3408 default:
Torok Edwinc23197a2009-07-14 16:55:14 +00003409 llvm_unreachable("Unhandled SetCC Equivalent!");
Bill Wendlingae89bb12008-11-11 08:25:46 +00003410 case ISD::SETCC:
Bill Wendling317bd702009-01-30 21:14:50 +00003411 return DAG.getSetCC(N->getDebugLoc(), VT, LHS, RHS, NotCC);
Bill Wendlingae89bb12008-11-11 08:25:46 +00003412 case ISD::SELECT_CC:
Bill Wendling317bd702009-01-30 21:14:50 +00003413 return DAG.getSelectCC(N->getDebugLoc(), LHS, RHS, N0.getOperand(2),
Bill Wendlingae89bb12008-11-11 08:25:46 +00003414 N0.getOperand(3), NotCC);
3415 }
3416 }
Nate Begeman1d4d4142005-09-01 00:19:25 +00003417 }
Bill Wendlingae89bb12008-11-11 08:25:46 +00003418
Chris Lattner61c5ff42007-09-10 21:39:07 +00003419 // fold (not (zext (setcc x, y))) -> (zext (not (setcc x, y)))
Dan Gohman002e5d02008-03-13 22:13:53 +00003420 if (N1C && N1C->getAPIntValue() == 1 && N0.getOpcode() == ISD::ZERO_EXTEND &&
Gabor Greif12632d22008-08-30 19:29:20 +00003421 N0.getNode()->hasOneUse() &&
3422 isSetCCEquivalent(N0.getOperand(0), LHS, RHS, CC)){
Dan Gohman475871a2008-07-27 21:46:04 +00003423 SDValue V = N0.getOperand(0);
Scott Michelfdc40a02009-02-17 22:15:04 +00003424 V = DAG.getNode(ISD::XOR, N0.getDebugLoc(), V.getValueType(), V,
Duncan Sands272dce02007-10-10 09:54:50 +00003425 DAG.getConstant(1, V.getValueType()));
Gabor Greifba36cb52008-08-28 21:40:38 +00003426 AddToWorkList(V.getNode());
Bill Wendling317bd702009-01-30 21:14:50 +00003427 return DAG.getNode(ISD::ZERO_EXTEND, N->getDebugLoc(), VT, V);
Chris Lattner61c5ff42007-09-10 21:39:07 +00003428 }
Scott Michelfdc40a02009-02-17 22:15:04 +00003429
Sylvestre Ledru94c22712012-09-27 10:14:43 +00003430 // fold (not (or x, y)) -> (and (not x), (not y)) iff x or y are setcc
Owen Anderson825b72b2009-08-11 20:47:22 +00003431 if (N1C && N1C->getAPIntValue() == 1 && VT == MVT::i1 &&
Nate Begeman99801192005-09-07 23:25:52 +00003432 (N0.getOpcode() == ISD::OR || N0.getOpcode() == ISD::AND)) {
Dan Gohman475871a2008-07-27 21:46:04 +00003433 SDValue LHS = N0.getOperand(0), RHS = N0.getOperand(1);
Nate Begeman99801192005-09-07 23:25:52 +00003434 if (isOneUseSetCC(RHS) || isOneUseSetCC(LHS)) {
3435 unsigned NewOpcode = N0.getOpcode() == ISD::AND ? ISD::OR : ISD::AND;
Bill Wendling317bd702009-01-30 21:14:50 +00003436 LHS = DAG.getNode(ISD::XOR, LHS.getDebugLoc(), VT, LHS, N1); // LHS = ~LHS
3437 RHS = DAG.getNode(ISD::XOR, RHS.getDebugLoc(), VT, RHS, N1); // RHS = ~RHS
Gabor Greifba36cb52008-08-28 21:40:38 +00003438 AddToWorkList(LHS.getNode()); AddToWorkList(RHS.getNode());
Bill Wendling317bd702009-01-30 21:14:50 +00003439 return DAG.getNode(NewOpcode, N->getDebugLoc(), VT, LHS, RHS);
Nate Begeman1d4d4142005-09-01 00:19:25 +00003440 }
3441 }
Sylvestre Ledru94c22712012-09-27 10:14:43 +00003442 // fold (not (or x, y)) -> (and (not x), (not y)) iff x or y are constants
Scott Michelfdc40a02009-02-17 22:15:04 +00003443 if (N1C && N1C->isAllOnesValue() &&
Nate Begeman99801192005-09-07 23:25:52 +00003444 (N0.getOpcode() == ISD::OR || N0.getOpcode() == ISD::AND)) {
Dan Gohman475871a2008-07-27 21:46:04 +00003445 SDValue LHS = N0.getOperand(0), RHS = N0.getOperand(1);
Nate Begeman99801192005-09-07 23:25:52 +00003446 if (isa<ConstantSDNode>(RHS) || isa<ConstantSDNode>(LHS)) {
3447 unsigned NewOpcode = N0.getOpcode() == ISD::AND ? ISD::OR : ISD::AND;
Bill Wendling317bd702009-01-30 21:14:50 +00003448 LHS = DAG.getNode(ISD::XOR, LHS.getDebugLoc(), VT, LHS, N1); // LHS = ~LHS
3449 RHS = DAG.getNode(ISD::XOR, RHS.getDebugLoc(), VT, RHS, N1); // RHS = ~RHS
Gabor Greifba36cb52008-08-28 21:40:38 +00003450 AddToWorkList(LHS.getNode()); AddToWorkList(RHS.getNode());
Bill Wendling317bd702009-01-30 21:14:50 +00003451 return DAG.getNode(NewOpcode, N->getDebugLoc(), VT, LHS, RHS);
Nate Begeman1d4d4142005-09-01 00:19:25 +00003452 }
3453 }
Bill Wendling317bd702009-01-30 21:14:50 +00003454 // fold (xor (xor x, c1), c2) -> (xor x, (xor c1, c2))
Nate Begeman223df222005-09-08 20:18:10 +00003455 if (N1C && N0.getOpcode() == ISD::XOR) {
3456 ConstantSDNode *N00C = dyn_cast<ConstantSDNode>(N0.getOperand(0));
3457 ConstantSDNode *N01C = dyn_cast<ConstantSDNode>(N0.getOperand(1));
3458 if (N00C)
Bill Wendling317bd702009-01-30 21:14:50 +00003459 return DAG.getNode(ISD::XOR, N->getDebugLoc(), VT, N0.getOperand(1),
3460 DAG.getConstant(N1C->getAPIntValue() ^
Dan Gohman002e5d02008-03-13 22:13:53 +00003461 N00C->getAPIntValue(), VT));
Nate Begeman223df222005-09-08 20:18:10 +00003462 if (N01C)
Bill Wendling317bd702009-01-30 21:14:50 +00003463 return DAG.getNode(ISD::XOR, N->getDebugLoc(), VT, N0.getOperand(0),
3464 DAG.getConstant(N1C->getAPIntValue() ^
Dan Gohman002e5d02008-03-13 22:13:53 +00003465 N01C->getAPIntValue(), VT));
Nate Begeman223df222005-09-08 20:18:10 +00003466 }
3467 // fold (xor x, x) -> 0
Eric Christopher7bccf6a2011-02-16 04:50:12 +00003468 if (N0 == N1)
3469 return tryFoldToZero(N->getDebugLoc(), TLI, VT, DAG, LegalOperations);
Scott Michelfdc40a02009-02-17 22:15:04 +00003470
Chris Lattner35e5c142006-05-05 05:51:50 +00003471 // Simplify: xor (op x...), (op y...) -> (op (xor x, y))
3472 if (N0.getOpcode() == N1.getOpcode()) {
Dan Gohman475871a2008-07-27 21:46:04 +00003473 SDValue Tmp = SimplifyBinOpWithSameOpcodeHands(N);
Gabor Greifba36cb52008-08-28 21:40:38 +00003474 if (Tmp.getNode()) return Tmp;
Nate Begeman39ee1ac2005-09-09 19:49:52 +00003475 }
Scott Michelfdc40a02009-02-17 22:15:04 +00003476
Chris Lattner3e104b12006-04-08 04:15:24 +00003477 // Simplify the expression using non-local knowledge.
Duncan Sands83ec4b62008-06-06 12:08:01 +00003478 if (!VT.isVector() &&
Dan Gohman475871a2008-07-27 21:46:04 +00003479 SimplifyDemandedBits(SDValue(N, 0)))
3480 return SDValue(N, 0);
Scott Michelfdc40a02009-02-17 22:15:04 +00003481
Evan Chengb3a3d5e2010-04-28 07:10:39 +00003482 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00003483}
3484
Chris Lattnere70da202007-12-06 07:33:36 +00003485/// visitShiftByConstant - Handle transforms common to the three shifts, when
3486/// the shift amount is a constant.
Dan Gohman475871a2008-07-27 21:46:04 +00003487SDValue DAGCombiner::visitShiftByConstant(SDNode *N, unsigned Amt) {
Gabor Greifba36cb52008-08-28 21:40:38 +00003488 SDNode *LHS = N->getOperand(0).getNode();
Dan Gohman475871a2008-07-27 21:46:04 +00003489 if (!LHS->hasOneUse()) return SDValue();
Scott Michelfdc40a02009-02-17 22:15:04 +00003490
Chris Lattnere70da202007-12-06 07:33:36 +00003491 // We want to pull some binops through shifts, so that we have (and (shift))
3492 // instead of (shift (and)), likewise for add, or, xor, etc. This sort of
3493 // thing happens with address calculations, so it's important to canonicalize
3494 // it.
3495 bool HighBitSet = false; // Can we transform this if the high bit is set?
Scott Michelfdc40a02009-02-17 22:15:04 +00003496
Chris Lattnere70da202007-12-06 07:33:36 +00003497 switch (LHS->getOpcode()) {
Dan Gohman475871a2008-07-27 21:46:04 +00003498 default: return SDValue();
Chris Lattnere70da202007-12-06 07:33:36 +00003499 case ISD::OR:
3500 case ISD::XOR:
3501 HighBitSet = false; // We can only transform sra if the high bit is clear.
3502 break;
3503 case ISD::AND:
3504 HighBitSet = true; // We can only transform sra if the high bit is set.
3505 break;
3506 case ISD::ADD:
Scott Michelfdc40a02009-02-17 22:15:04 +00003507 if (N->getOpcode() != ISD::SHL)
Dan Gohman475871a2008-07-27 21:46:04 +00003508 return SDValue(); // only shl(add) not sr[al](add).
Chris Lattnere70da202007-12-06 07:33:36 +00003509 HighBitSet = false; // We can only transform sra if the high bit is clear.
3510 break;
3511 }
Scott Michelfdc40a02009-02-17 22:15:04 +00003512
Chris Lattnere70da202007-12-06 07:33:36 +00003513 // We require the RHS of the binop to be a constant as well.
3514 ConstantSDNode *BinOpCst = dyn_cast<ConstantSDNode>(LHS->getOperand(1));
Dan Gohman475871a2008-07-27 21:46:04 +00003515 if (!BinOpCst) return SDValue();
Bill Wendling88103372009-01-30 21:37:17 +00003516
3517 // FIXME: disable this unless the input to the binop is a shift by a constant.
3518 // If it is not a shift, it pessimizes some common cases like:
Chris Lattnerd3fd6d22007-12-06 07:47:55 +00003519 //
Bill Wendling88103372009-01-30 21:37:17 +00003520 // void foo(int *X, int i) { X[i & 1235] = 1; }
3521 // int bar(int *X, int i) { return X[i & 255]; }
Gabor Greifba36cb52008-08-28 21:40:38 +00003522 SDNode *BinOpLHSVal = LHS->getOperand(0).getNode();
Scott Michelfdc40a02009-02-17 22:15:04 +00003523 if ((BinOpLHSVal->getOpcode() != ISD::SHL &&
Chris Lattnerd3fd6d22007-12-06 07:47:55 +00003524 BinOpLHSVal->getOpcode() != ISD::SRA &&
3525 BinOpLHSVal->getOpcode() != ISD::SRL) ||
3526 !isa<ConstantSDNode>(BinOpLHSVal->getOperand(1)))
Dan Gohman475871a2008-07-27 21:46:04 +00003527 return SDValue();
Scott Michelfdc40a02009-02-17 22:15:04 +00003528
Owen Andersone50ed302009-08-10 22:56:29 +00003529 EVT VT = N->getValueType(0);
Scott Michelfdc40a02009-02-17 22:15:04 +00003530
Bill Wendling88103372009-01-30 21:37:17 +00003531 // If this is a signed shift right, and the high bit is modified by the
3532 // logical operation, do not perform the transformation. The highBitSet
3533 // boolean indicates the value of the high bit of the constant which would
3534 // cause it to be modified for this operation.
Chris Lattnere70da202007-12-06 07:33:36 +00003535 if (N->getOpcode() == ISD::SRA) {
Dan Gohman220a8232008-03-03 23:51:38 +00003536 bool BinOpRHSSignSet = BinOpCst->getAPIntValue().isNegative();
3537 if (BinOpRHSSignSet != HighBitSet)
Dan Gohman475871a2008-07-27 21:46:04 +00003538 return SDValue();
Chris Lattnere70da202007-12-06 07:33:36 +00003539 }
Scott Michelfdc40a02009-02-17 22:15:04 +00003540
Chris Lattnere70da202007-12-06 07:33:36 +00003541 // Fold the constants, shifting the binop RHS by the shift amount.
Bill Wendling88103372009-01-30 21:37:17 +00003542 SDValue NewRHS = DAG.getNode(N->getOpcode(), LHS->getOperand(1).getDebugLoc(),
3543 N->getValueType(0),
3544 LHS->getOperand(1), N->getOperand(1));
Chris Lattnere70da202007-12-06 07:33:36 +00003545
3546 // Create the new shift.
Eric Christopher503a64d2010-12-09 04:48:06 +00003547 SDValue NewShift = DAG.getNode(N->getOpcode(),
3548 LHS->getOperand(0).getDebugLoc(),
Bill Wendling88103372009-01-30 21:37:17 +00003549 VT, LHS->getOperand(0), N->getOperand(1));
Chris Lattnere70da202007-12-06 07:33:36 +00003550
3551 // Create the new binop.
Bill Wendling88103372009-01-30 21:37:17 +00003552 return DAG.getNode(LHS->getOpcode(), N->getDebugLoc(), VT, NewShift, NewRHS);
Chris Lattnere70da202007-12-06 07:33:36 +00003553}
3554
Dan Gohman475871a2008-07-27 21:46:04 +00003555SDValue DAGCombiner::visitSHL(SDNode *N) {
3556 SDValue N0 = N->getOperand(0);
3557 SDValue N1 = N->getOperand(1);
Nate Begeman646d7e22005-09-02 21:18:40 +00003558 ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0);
3559 ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1);
Owen Andersone50ed302009-08-10 22:56:29 +00003560 EVT VT = N0.getValueType();
Dan Gohman87862e72009-12-11 21:31:27 +00003561 unsigned OpSizeInBits = VT.getScalarType().getSizeInBits();
Scott Michelfdc40a02009-02-17 22:15:04 +00003562
Nate Begeman1d4d4142005-09-01 00:19:25 +00003563 // fold (shl c1, c2) -> c1<<c2
Nate Begeman646d7e22005-09-02 21:18:40 +00003564 if (N0C && N1C)
Bill Wendlingf3cbca22008-09-24 10:25:02 +00003565 return DAG.FoldConstantArithmetic(ISD::SHL, VT, N0C, N1C);
Nate Begeman1d4d4142005-09-01 00:19:25 +00003566 // fold (shl 0, x) -> 0
Nate Begeman646d7e22005-09-02 21:18:40 +00003567 if (N0C && N0C->isNullValue())
Nate Begeman83e75ec2005-09-06 04:43:02 +00003568 return N0;
Nate Begeman1d4d4142005-09-01 00:19:25 +00003569 // fold (shl x, c >= size(x)) -> undef
Dan Gohmanf5aeb1a2008-09-12 16:56:44 +00003570 if (N1C && N1C->getZExtValue() >= OpSizeInBits)
Dale Johannesene8d72302009-02-06 23:05:02 +00003571 return DAG.getUNDEF(VT);
Nate Begeman1d4d4142005-09-01 00:19:25 +00003572 // fold (shl x, 0) -> x
Nate Begeman646d7e22005-09-02 21:18:40 +00003573 if (N1C && N1C->isNullValue())
Nate Begeman83e75ec2005-09-06 04:43:02 +00003574 return N0;
Chad Rosier92bcd962011-06-14 22:29:10 +00003575 // fold (shl undef, x) -> 0
3576 if (N0.getOpcode() == ISD::UNDEF)
3577 return DAG.getConstant(0, VT);
Nate Begeman1d4d4142005-09-01 00:19:25 +00003578 // if (shl x, c) is known to be zero, return 0
Dan Gohman475871a2008-07-27 21:46:04 +00003579 if (DAG.MaskedValueIsZero(SDValue(N, 0),
Dan Gohman87862e72009-12-11 21:31:27 +00003580 APInt::getAllOnesValue(OpSizeInBits)))
Nate Begeman83e75ec2005-09-06 04:43:02 +00003581 return DAG.getConstant(0, VT);
Duncan Sandsb0d5cdd2009-02-01 18:06:53 +00003582 // fold (shl x, (trunc (and y, c))) -> (shl x, (and (trunc y), (trunc c))).
Evan Chengeb9f8922008-08-30 02:03:58 +00003583 if (N1.getOpcode() == ISD::TRUNCATE &&
Evan Cheng242ebd12008-09-22 18:19:24 +00003584 N1.getOperand(0).getOpcode() == ISD::AND &&
3585 N1.hasOneUse() && N1.getOperand(0).hasOneUse()) {
Evan Chengeb9f8922008-08-30 02:03:58 +00003586 SDValue N101 = N1.getOperand(0).getOperand(1);
Evan Cheng242ebd12008-09-22 18:19:24 +00003587 if (ConstantSDNode *N101C = dyn_cast<ConstantSDNode>(N101)) {
Owen Andersone50ed302009-08-10 22:56:29 +00003588 EVT TruncVT = N1.getValueType();
Evan Cheng242ebd12008-09-22 18:19:24 +00003589 SDValue N100 = N1.getOperand(0).getOperand(0);
Duncan Sandsb0d5cdd2009-02-01 18:06:53 +00003590 APInt TruncC = N101C->getAPIntValue();
Jay Foad40f8f622010-12-07 08:25:19 +00003591 TruncC = TruncC.trunc(TruncVT.getSizeInBits());
Bill Wendling88103372009-01-30 21:37:17 +00003592 return DAG.getNode(ISD::SHL, N->getDebugLoc(), VT, N0,
Bill Wendlingfc4b6772009-02-01 11:19:36 +00003593 DAG.getNode(ISD::AND, N->getDebugLoc(), TruncVT,
3594 DAG.getNode(ISD::TRUNCATE,
3595 N->getDebugLoc(),
3596 TruncVT, N100),
Dan Gohmance9bc122009-01-27 20:39:34 +00003597 DAG.getConstant(TruncC, TruncVT)));
Evan Chengeb9f8922008-08-30 02:03:58 +00003598 }
3599 }
3600
Dan Gohman475871a2008-07-27 21:46:04 +00003601 if (N1C && SimplifyDemandedBits(SDValue(N, 0)))
3602 return SDValue(N, 0);
Bill Wendling88103372009-01-30 21:37:17 +00003603
3604 // fold (shl (shl x, c1), c2) -> 0 or (shl x, (add c1, c2))
Scott Michelfdc40a02009-02-17 22:15:04 +00003605 if (N1C && N0.getOpcode() == ISD::SHL &&
Nate Begeman1d4d4142005-09-01 00:19:25 +00003606 N0.getOperand(1).getOpcode() == ISD::Constant) {
Dan Gohmanf5aeb1a2008-09-12 16:56:44 +00003607 uint64_t c1 = cast<ConstantSDNode>(N0.getOperand(1))->getZExtValue();
3608 uint64_t c2 = N1C->getZExtValue();
Dale Johannesenc72b18c2010-12-21 21:55:50 +00003609 if (c1 + c2 >= OpSizeInBits)
Nate Begeman83e75ec2005-09-06 04:43:02 +00003610 return DAG.getConstant(0, VT);
Bill Wendling88103372009-01-30 21:37:17 +00003611 return DAG.getNode(ISD::SHL, N->getDebugLoc(), VT, N0.getOperand(0),
Nate Begeman83e75ec2005-09-06 04:43:02 +00003612 DAG.getConstant(c1 + c2, N1.getValueType()));
Nate Begeman1d4d4142005-09-01 00:19:25 +00003613 }
Dale Johannesenc72b18c2010-12-21 21:55:50 +00003614
3615 // fold (shl (ext (shl x, c1)), c2) -> (ext (shl x, (add c1, c2)))
3616 // For this to be valid, the second form must not preserve any of the bits
3617 // that are shifted out by the inner shift in the first form. This means
3618 // the outer shift size must be >= the number of bits added by the ext.
3619 // As a corollary, we don't care what kind of ext it is.
3620 if (N1C && (N0.getOpcode() == ISD::ZERO_EXTEND ||
3621 N0.getOpcode() == ISD::ANY_EXTEND ||
3622 N0.getOpcode() == ISD::SIGN_EXTEND) &&
3623 N0.getOperand(0).getOpcode() == ISD::SHL &&
3624 isa<ConstantSDNode>(N0.getOperand(0)->getOperand(1))) {
Owen Anderson95771af2011-02-25 21:41:48 +00003625 uint64_t c1 =
Dale Johannesenc72b18c2010-12-21 21:55:50 +00003626 cast<ConstantSDNode>(N0.getOperand(0)->getOperand(1))->getZExtValue();
3627 uint64_t c2 = N1C->getZExtValue();
3628 EVT InnerShiftVT = N0.getOperand(0).getValueType();
3629 uint64_t InnerShiftSize = InnerShiftVT.getScalarType().getSizeInBits();
3630 if (c2 >= OpSizeInBits - InnerShiftSize) {
3631 if (c1 + c2 >= OpSizeInBits)
3632 return DAG.getConstant(0, VT);
3633 return DAG.getNode(ISD::SHL, N0->getDebugLoc(), VT,
3634 DAG.getNode(N0.getOpcode(), N0->getDebugLoc(), VT,
3635 N0.getOperand(0)->getOperand(0)),
3636 DAG.getConstant(c1 + c2, N1.getValueType()));
3637 }
3638 }
3639
Eli Friedman2a6d9eb2011-06-09 22:14:44 +00003640 // fold (shl (srl x, c1), c2) -> (and (shl x, (sub c2, c1), MASK) or
3641 // (and (srl x, (sub c1, c2), MASK)
Chandler Carruth62dfc512012-01-05 11:05:55 +00003642 // Only fold this if the inner shift has no other uses -- if it does, folding
3643 // this will increase the total number of instructions.
3644 if (N1C && N0.getOpcode() == ISD::SRL && N0.hasOneUse() &&
Nate Begeman1d4d4142005-09-01 00:19:25 +00003645 N0.getOperand(1).getOpcode() == ISD::Constant) {
Dan Gohmanf5aeb1a2008-09-12 16:56:44 +00003646 uint64_t c1 = cast<ConstantSDNode>(N0.getOperand(1))->getZExtValue();
Evan Chengd101a722009-07-21 05:40:15 +00003647 if (c1 < VT.getSizeInBits()) {
3648 uint64_t c2 = N1C->getZExtValue();
Eli Friedman2a6d9eb2011-06-09 22:14:44 +00003649 APInt Mask = APInt::getHighBitsSet(VT.getSizeInBits(),
3650 VT.getSizeInBits() - c1);
3651 SDValue Shift;
3652 if (c2 > c1) {
3653 Mask = Mask.shl(c2-c1);
3654 Shift = DAG.getNode(ISD::SHL, N->getDebugLoc(), VT, N0.getOperand(0),
3655 DAG.getConstant(c2-c1, N1.getValueType()));
3656 } else {
3657 Mask = Mask.lshr(c1-c2);
3658 Shift = DAG.getNode(ISD::SRL, N->getDebugLoc(), VT, N0.getOperand(0),
3659 DAG.getConstant(c1-c2, N1.getValueType()));
3660 }
3661 return DAG.getNode(ISD::AND, N0.getDebugLoc(), VT, Shift,
3662 DAG.getConstant(Mask, VT));
Evan Chengd101a722009-07-21 05:40:15 +00003663 }
Nate Begeman1d4d4142005-09-01 00:19:25 +00003664 }
Bill Wendling88103372009-01-30 21:37:17 +00003665 // fold (shl (sra x, c1), c1) -> (and x, (shl -1, c1))
Dan Gohman5cbd37e2009-08-06 09:18:59 +00003666 if (N1C && N0.getOpcode() == ISD::SRA && N1 == N0.getOperand(1)) {
3667 SDValue HiBitsMask =
3668 DAG.getConstant(APInt::getHighBitsSet(VT.getSizeInBits(),
3669 VT.getSizeInBits() -
3670 N1C->getZExtValue()),
3671 VT);
Bill Wendling88103372009-01-30 21:37:17 +00003672 return DAG.getNode(ISD::AND, N->getDebugLoc(), VT, N0.getOperand(0),
Dan Gohman5cbd37e2009-08-06 09:18:59 +00003673 HiBitsMask);
3674 }
Scott Michelfdc40a02009-02-17 22:15:04 +00003675
Evan Chenge5b51ac2010-04-17 06:13:15 +00003676 if (N1C) {
3677 SDValue NewSHL = visitShiftByConstant(N, N1C->getZExtValue());
3678 if (NewSHL.getNode())
3679 return NewSHL;
3680 }
3681
Evan Chengb3a3d5e2010-04-28 07:10:39 +00003682 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00003683}
3684
Dan Gohman475871a2008-07-27 21:46:04 +00003685SDValue DAGCombiner::visitSRA(SDNode *N) {
3686 SDValue N0 = N->getOperand(0);
3687 SDValue N1 = N->getOperand(1);
Nate Begeman646d7e22005-09-02 21:18:40 +00003688 ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0);
3689 ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1);
Owen Andersone50ed302009-08-10 22:56:29 +00003690 EVT VT = N0.getValueType();
Dan Gohman87862e72009-12-11 21:31:27 +00003691 unsigned OpSizeInBits = VT.getScalarType().getSizeInBits();
Scott Michelfdc40a02009-02-17 22:15:04 +00003692
Bill Wendling88103372009-01-30 21:37:17 +00003693 // fold (sra c1, c2) -> (sra c1, c2)
Nate Begeman646d7e22005-09-02 21:18:40 +00003694 if (N0C && N1C)
Bill Wendlingf3cbca22008-09-24 10:25:02 +00003695 return DAG.FoldConstantArithmetic(ISD::SRA, VT, N0C, N1C);
Nate Begeman1d4d4142005-09-01 00:19:25 +00003696 // fold (sra 0, x) -> 0
Nate Begeman646d7e22005-09-02 21:18:40 +00003697 if (N0C && N0C->isNullValue())
Nate Begeman83e75ec2005-09-06 04:43:02 +00003698 return N0;
Nate Begeman1d4d4142005-09-01 00:19:25 +00003699 // fold (sra -1, x) -> -1
Nate Begeman646d7e22005-09-02 21:18:40 +00003700 if (N0C && N0C->isAllOnesValue())
Nate Begeman83e75ec2005-09-06 04:43:02 +00003701 return N0;
Bill Wendling88103372009-01-30 21:37:17 +00003702 // fold (sra x, (setge c, size(x))) -> undef
Dan Gohman87862e72009-12-11 21:31:27 +00003703 if (N1C && N1C->getZExtValue() >= OpSizeInBits)
Dale Johannesene8d72302009-02-06 23:05:02 +00003704 return DAG.getUNDEF(VT);
Nate Begeman1d4d4142005-09-01 00:19:25 +00003705 // fold (sra x, 0) -> x
Nate Begeman646d7e22005-09-02 21:18:40 +00003706 if (N1C && N1C->isNullValue())
Nate Begeman83e75ec2005-09-06 04:43:02 +00003707 return N0;
Nate Begemanfb7217b2006-02-17 19:54:08 +00003708 // fold (sra (shl x, c1), c1) -> sext_inreg for some c1 and target supports
3709 // sext_inreg.
3710 if (N1C && N0.getOpcode() == ISD::SHL && N1 == N0.getOperand(1)) {
Dan Gohman87862e72009-12-11 21:31:27 +00003711 unsigned LowBits = OpSizeInBits - (unsigned)N1C->getZExtValue();
Dan Gohmand1996362010-01-09 02:13:55 +00003712 EVT ExtVT = EVT::getIntegerVT(*DAG.getContext(), LowBits);
3713 if (VT.isVector())
3714 ExtVT = EVT::getVectorVT(*DAG.getContext(),
3715 ExtVT, VT.getVectorNumElements());
3716 if ((!LegalOperations ||
3717 TLI.isOperationLegal(ISD::SIGN_EXTEND_INREG, ExtVT)))
Bill Wendling88103372009-01-30 21:37:17 +00003718 return DAG.getNode(ISD::SIGN_EXTEND_INREG, N->getDebugLoc(), VT,
Dan Gohmand1996362010-01-09 02:13:55 +00003719 N0.getOperand(0), DAG.getValueType(ExtVT));
Nate Begemanfb7217b2006-02-17 19:54:08 +00003720 }
Duncan Sandsd4b9c172008-06-13 19:07:40 +00003721
Bill Wendling88103372009-01-30 21:37:17 +00003722 // fold (sra (sra x, c1), c2) -> (sra x, (add c1, c2))
Chris Lattner71d9ebc2006-02-28 06:23:04 +00003723 if (N1C && N0.getOpcode() == ISD::SRA) {
3724 if (ConstantSDNode *C1 = dyn_cast<ConstantSDNode>(N0.getOperand(1))) {
Dan Gohmanf5aeb1a2008-09-12 16:56:44 +00003725 unsigned Sum = N1C->getZExtValue() + C1->getZExtValue();
Dan Gohman87862e72009-12-11 21:31:27 +00003726 if (Sum >= OpSizeInBits) Sum = OpSizeInBits-1;
Bill Wendling88103372009-01-30 21:37:17 +00003727 return DAG.getNode(ISD::SRA, N->getDebugLoc(), VT, N0.getOperand(0),
Chris Lattner71d9ebc2006-02-28 06:23:04 +00003728 DAG.getConstant(Sum, N1C->getValueType(0)));
3729 }
3730 }
Christopher Lamb15cbde32008-03-19 08:30:06 +00003731
Bill Wendling88103372009-01-30 21:37:17 +00003732 // fold (sra (shl X, m), (sub result_size, n))
3733 // -> (sign_extend (trunc (shl X, (sub (sub result_size, n), m)))) for
Scott Michelfdc40a02009-02-17 22:15:04 +00003734 // result_size - n != m.
3735 // If truncate is free for the target sext(shl) is likely to result in better
Christopher Lambb9b04282008-03-20 04:31:39 +00003736 // code.
Christopher Lamb15cbde32008-03-19 08:30:06 +00003737 if (N0.getOpcode() == ISD::SHL) {
3738 // Get the two constanst of the shifts, CN0 = m, CN = n.
3739 const ConstantSDNode *N01C = dyn_cast<ConstantSDNode>(N0.getOperand(1));
3740 if (N01C && N1C) {
Christopher Lambb9b04282008-03-20 04:31:39 +00003741 // Determine what the truncate's result bitsize and type would be.
Owen Andersone50ed302009-08-10 22:56:29 +00003742 EVT TruncVT =
Eric Christopher503a64d2010-12-09 04:48:06 +00003743 EVT::getIntegerVT(*DAG.getContext(),
3744 OpSizeInBits - N1C->getZExtValue());
Christopher Lambb9b04282008-03-20 04:31:39 +00003745 // Determine the residual right-shift amount.
Torok Edwin6bb49582009-05-23 17:29:48 +00003746 signed ShiftAmt = N1C->getZExtValue() - N01C->getZExtValue();
Duncan Sandsd4b9c172008-06-13 19:07:40 +00003747
Scott Michelfdc40a02009-02-17 22:15:04 +00003748 // If the shift is not a no-op (in which case this should be just a sign
3749 // extend already), the truncated to type is legal, sign_extend is legal
Dan Gohmanf451cb82010-02-10 16:03:48 +00003750 // on that type, and the truncate to that type is both legal and free,
Christopher Lambb9b04282008-03-20 04:31:39 +00003751 // perform the transform.
Torok Edwin6bb49582009-05-23 17:29:48 +00003752 if ((ShiftAmt > 0) &&
Dan Gohmanf560ffa2009-01-28 17:46:25 +00003753 TLI.isOperationLegalOrCustom(ISD::SIGN_EXTEND, TruncVT) &&
3754 TLI.isOperationLegalOrCustom(ISD::TRUNCATE, VT) &&
Evan Cheng260e07e2008-03-20 02:18:41 +00003755 TLI.isTruncateFree(VT, TruncVT)) {
Christopher Lambb9b04282008-03-20 04:31:39 +00003756
Owen Anderson95771af2011-02-25 21:41:48 +00003757 SDValue Amt = DAG.getConstant(ShiftAmt,
3758 getShiftAmountTy(N0.getOperand(0).getValueType()));
Bill Wendling88103372009-01-30 21:37:17 +00003759 SDValue Shift = DAG.getNode(ISD::SRL, N0.getDebugLoc(), VT,
3760 N0.getOperand(0), Amt);
3761 SDValue Trunc = DAG.getNode(ISD::TRUNCATE, N0.getDebugLoc(), TruncVT,
3762 Shift);
3763 return DAG.getNode(ISD::SIGN_EXTEND, N->getDebugLoc(),
3764 N->getValueType(0), Trunc);
Christopher Lamb15cbde32008-03-19 08:30:06 +00003765 }
3766 }
3767 }
Scott Michelfdc40a02009-02-17 22:15:04 +00003768
Duncan Sandsb0d5cdd2009-02-01 18:06:53 +00003769 // fold (sra x, (trunc (and y, c))) -> (sra x, (and (trunc y), (trunc c))).
Evan Chengeb9f8922008-08-30 02:03:58 +00003770 if (N1.getOpcode() == ISD::TRUNCATE &&
Evan Cheng242ebd12008-09-22 18:19:24 +00003771 N1.getOperand(0).getOpcode() == ISD::AND &&
3772 N1.hasOneUse() && N1.getOperand(0).hasOneUse()) {
Evan Chengeb9f8922008-08-30 02:03:58 +00003773 SDValue N101 = N1.getOperand(0).getOperand(1);
Evan Cheng242ebd12008-09-22 18:19:24 +00003774 if (ConstantSDNode *N101C = dyn_cast<ConstantSDNode>(N101)) {
Owen Andersone50ed302009-08-10 22:56:29 +00003775 EVT TruncVT = N1.getValueType();
Evan Cheng242ebd12008-09-22 18:19:24 +00003776 SDValue N100 = N1.getOperand(0).getOperand(0);
Duncan Sandsb0d5cdd2009-02-01 18:06:53 +00003777 APInt TruncC = N101C->getAPIntValue();
Jay Foad40f8f622010-12-07 08:25:19 +00003778 TruncC = TruncC.trunc(TruncVT.getScalarType().getSizeInBits());
Bill Wendling88103372009-01-30 21:37:17 +00003779 return DAG.getNode(ISD::SRA, N->getDebugLoc(), VT, N0,
Bill Wendling9729c5a2009-01-31 03:12:48 +00003780 DAG.getNode(ISD::AND, N->getDebugLoc(),
Bill Wendling88103372009-01-30 21:37:17 +00003781 TruncVT,
Bill Wendling9729c5a2009-01-31 03:12:48 +00003782 DAG.getNode(ISD::TRUNCATE,
3783 N->getDebugLoc(),
3784 TruncVT, N100),
Dan Gohmance9bc122009-01-27 20:39:34 +00003785 DAG.getConstant(TruncC, TruncVT)));
Evan Chengeb9f8922008-08-30 02:03:58 +00003786 }
3787 }
3788
Benjamin Kramer9b108a32011-01-30 16:38:43 +00003789 // fold (sra (trunc (sr x, c1)), c2) -> (trunc (sra x, c1+c2))
3790 // if c1 is equal to the number of bits the trunc removes
3791 if (N0.getOpcode() == ISD::TRUNCATE &&
3792 (N0.getOperand(0).getOpcode() == ISD::SRL ||
3793 N0.getOperand(0).getOpcode() == ISD::SRA) &&
3794 N0.getOperand(0).hasOneUse() &&
3795 N0.getOperand(0).getOperand(1).hasOneUse() &&
3796 N1C && isa<ConstantSDNode>(N0.getOperand(0).getOperand(1))) {
3797 EVT LargeVT = N0.getOperand(0).getValueType();
3798 ConstantSDNode *LargeShiftAmt =
3799 cast<ConstantSDNode>(N0.getOperand(0).getOperand(1));
3800
3801 if (LargeVT.getScalarType().getSizeInBits() - OpSizeInBits ==
3802 LargeShiftAmt->getZExtValue()) {
3803 SDValue Amt =
3804 DAG.getConstant(LargeShiftAmt->getZExtValue() + N1C->getZExtValue(),
Owen Anderson95771af2011-02-25 21:41:48 +00003805 getShiftAmountTy(N0.getOperand(0).getOperand(0).getValueType()));
Benjamin Kramer9b108a32011-01-30 16:38:43 +00003806 SDValue SRA = DAG.getNode(ISD::SRA, N->getDebugLoc(), LargeVT,
3807 N0.getOperand(0).getOperand(0), Amt);
3808 return DAG.getNode(ISD::TRUNCATE, N->getDebugLoc(), VT, SRA);
3809 }
3810 }
3811
Scott Michelfdc40a02009-02-17 22:15:04 +00003812 // Simplify, based on bits shifted out of the LHS.
Dan Gohman475871a2008-07-27 21:46:04 +00003813 if (N1C && SimplifyDemandedBits(SDValue(N, 0)))
3814 return SDValue(N, 0);
Scott Michelfdc40a02009-02-17 22:15:04 +00003815
3816
Nate Begeman1d4d4142005-09-01 00:19:25 +00003817 // If the sign bit is known to be zero, switch this to a SRL.
Dan Gohman2e68b6f2008-02-25 21:11:39 +00003818 if (DAG.SignBitIsZero(N0))
Bill Wendling88103372009-01-30 21:37:17 +00003819 return DAG.getNode(ISD::SRL, N->getDebugLoc(), VT, N0, N1);
Chris Lattnere70da202007-12-06 07:33:36 +00003820
Evan Chenge5b51ac2010-04-17 06:13:15 +00003821 if (N1C) {
3822 SDValue NewSRA = visitShiftByConstant(N, N1C->getZExtValue());
3823 if (NewSRA.getNode())
3824 return NewSRA;
3825 }
3826
Evan Chengb3a3d5e2010-04-28 07:10:39 +00003827 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00003828}
3829
Dan Gohman475871a2008-07-27 21:46:04 +00003830SDValue DAGCombiner::visitSRL(SDNode *N) {
3831 SDValue N0 = N->getOperand(0);
3832 SDValue N1 = N->getOperand(1);
Nate Begeman646d7e22005-09-02 21:18:40 +00003833 ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0);
3834 ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1);
Owen Andersone50ed302009-08-10 22:56:29 +00003835 EVT VT = N0.getValueType();
Dan Gohman87862e72009-12-11 21:31:27 +00003836 unsigned OpSizeInBits = VT.getScalarType().getSizeInBits();
Scott Michelfdc40a02009-02-17 22:15:04 +00003837
Nate Begeman1d4d4142005-09-01 00:19:25 +00003838 // fold (srl c1, c2) -> c1 >>u c2
Nate Begeman646d7e22005-09-02 21:18:40 +00003839 if (N0C && N1C)
Bill Wendlingf3cbca22008-09-24 10:25:02 +00003840 return DAG.FoldConstantArithmetic(ISD::SRL, VT, N0C, N1C);
Nate Begeman1d4d4142005-09-01 00:19:25 +00003841 // fold (srl 0, x) -> 0
Nate Begeman646d7e22005-09-02 21:18:40 +00003842 if (N0C && N0C->isNullValue())
Nate Begeman83e75ec2005-09-06 04:43:02 +00003843 return N0;
Nate Begeman1d4d4142005-09-01 00:19:25 +00003844 // fold (srl x, c >= size(x)) -> undef
Dan Gohmanf5aeb1a2008-09-12 16:56:44 +00003845 if (N1C && N1C->getZExtValue() >= OpSizeInBits)
Dale Johannesene8d72302009-02-06 23:05:02 +00003846 return DAG.getUNDEF(VT);
Nate Begeman1d4d4142005-09-01 00:19:25 +00003847 // fold (srl x, 0) -> x
Nate Begeman646d7e22005-09-02 21:18:40 +00003848 if (N1C && N1C->isNullValue())
Nate Begeman83e75ec2005-09-06 04:43:02 +00003849 return N0;
Nate Begeman1d4d4142005-09-01 00:19:25 +00003850 // if (srl x, c) is known to be zero, return 0
Dan Gohman475871a2008-07-27 21:46:04 +00003851 if (N1C && DAG.MaskedValueIsZero(SDValue(N, 0),
Dan Gohman2e68b6f2008-02-25 21:11:39 +00003852 APInt::getAllOnesValue(OpSizeInBits)))
Nate Begeman83e75ec2005-09-06 04:43:02 +00003853 return DAG.getConstant(0, VT);
Scott Michelfdc40a02009-02-17 22:15:04 +00003854
Bill Wendling88103372009-01-30 21:37:17 +00003855 // fold (srl (srl x, c1), c2) -> 0 or (srl x, (add c1, c2))
Scott Michelfdc40a02009-02-17 22:15:04 +00003856 if (N1C && N0.getOpcode() == ISD::SRL &&
Nate Begeman1d4d4142005-09-01 00:19:25 +00003857 N0.getOperand(1).getOpcode() == ISD::Constant) {
Dan Gohmanf5aeb1a2008-09-12 16:56:44 +00003858 uint64_t c1 = cast<ConstantSDNode>(N0.getOperand(1))->getZExtValue();
3859 uint64_t c2 = N1C->getZExtValue();
Dale Johannesenc72b18c2010-12-21 21:55:50 +00003860 if (c1 + c2 >= OpSizeInBits)
Nate Begeman83e75ec2005-09-06 04:43:02 +00003861 return DAG.getConstant(0, VT);
Bill Wendling88103372009-01-30 21:37:17 +00003862 return DAG.getNode(ISD::SRL, N->getDebugLoc(), VT, N0.getOperand(0),
Nate Begeman83e75ec2005-09-06 04:43:02 +00003863 DAG.getConstant(c1 + c2, N1.getValueType()));
Nate Begeman1d4d4142005-09-01 00:19:25 +00003864 }
Wesley Peckbf17cfa2010-11-23 03:31:01 +00003865
Dale Johannesenf5daf8b2010-12-17 21:45:49 +00003866 // fold (srl (trunc (srl x, c1)), c2) -> 0 or (trunc (srl x, (add c1, c2)))
Dale Johannesenf5daf8b2010-12-17 21:45:49 +00003867 if (N1C && N0.getOpcode() == ISD::TRUNCATE &&
3868 N0.getOperand(0).getOpcode() == ISD::SRL &&
Dale Johannesen025cc6e2010-12-20 20:10:50 +00003869 isa<ConstantSDNode>(N0.getOperand(0)->getOperand(1))) {
Owen Anderson95771af2011-02-25 21:41:48 +00003870 uint64_t c1 =
Dale Johannesenf5daf8b2010-12-17 21:45:49 +00003871 cast<ConstantSDNode>(N0.getOperand(0)->getOperand(1))->getZExtValue();
3872 uint64_t c2 = N1C->getZExtValue();
Dale Johannesenc72b18c2010-12-21 21:55:50 +00003873 EVT InnerShiftVT = N0.getOperand(0).getValueType();
3874 EVT ShiftCountVT = N0.getOperand(0)->getOperand(1).getValueType();
Dale Johannesenf5daf8b2010-12-17 21:45:49 +00003875 uint64_t InnerShiftSize = InnerShiftVT.getScalarType().getSizeInBits();
Dale Johannesen025cc6e2010-12-20 20:10:50 +00003876 // This is only valid if the OpSizeInBits + c1 = size of inner shift.
Dale Johannesenf5daf8b2010-12-17 21:45:49 +00003877 if (c1 + OpSizeInBits == InnerShiftSize) {
3878 if (c1 + c2 >= InnerShiftSize)
3879 return DAG.getConstant(0, VT);
3880 return DAG.getNode(ISD::TRUNCATE, N0->getDebugLoc(), VT,
Owen Anderson95771af2011-02-25 21:41:48 +00003881 DAG.getNode(ISD::SRL, N0->getDebugLoc(), InnerShiftVT,
Dale Johannesenf5daf8b2010-12-17 21:45:49 +00003882 N0.getOperand(0)->getOperand(0),
Dale Johannesenc72b18c2010-12-21 21:55:50 +00003883 DAG.getConstant(c1 + c2, ShiftCountVT)));
Dale Johannesenf5daf8b2010-12-17 21:45:49 +00003884 }
3885 }
3886
Chris Lattnerefcddc32010-04-15 05:28:43 +00003887 // fold (srl (shl x, c), c) -> (and x, cst2)
3888 if (N1C && N0.getOpcode() == ISD::SHL && N0.getOperand(1) == N1 &&
3889 N0.getValueSizeInBits() <= 64) {
3890 uint64_t ShAmt = N1C->getZExtValue()+64-N0.getValueSizeInBits();
3891 return DAG.getNode(ISD::AND, N->getDebugLoc(), VT, N0.getOperand(0),
3892 DAG.getConstant(~0ULL >> ShAmt, VT));
3893 }
Wesley Peckbf17cfa2010-11-23 03:31:01 +00003894
Scott Michelfdc40a02009-02-17 22:15:04 +00003895
Chris Lattner06afe072006-05-05 22:53:17 +00003896 // fold (srl (anyextend x), c) -> (anyextend (srl x, c))
3897 if (N1C && N0.getOpcode() == ISD::ANY_EXTEND) {
3898 // Shifting in all undef bits?
Owen Andersone50ed302009-08-10 22:56:29 +00003899 EVT SmallVT = N0.getOperand(0).getValueType();
Dan Gohmanf5aeb1a2008-09-12 16:56:44 +00003900 if (N1C->getZExtValue() >= SmallVT.getSizeInBits())
Dale Johannesene8d72302009-02-06 23:05:02 +00003901 return DAG.getUNDEF(VT);
Chris Lattner06afe072006-05-05 22:53:17 +00003902
Evan Chenge5b51ac2010-04-17 06:13:15 +00003903 if (!LegalTypes || TLI.isTypeDesirableForOp(ISD::SRL, SmallVT)) {
Owen Andersona34d9362011-04-14 17:30:49 +00003904 uint64_t ShiftAmt = N1C->getZExtValue();
Evan Chenge5b51ac2010-04-17 06:13:15 +00003905 SDValue SmallShift = DAG.getNode(ISD::SRL, N0.getDebugLoc(), SmallVT,
Owen Andersona34d9362011-04-14 17:30:49 +00003906 N0.getOperand(0),
3907 DAG.getConstant(ShiftAmt, getShiftAmountTy(SmallVT)));
Evan Chenge5b51ac2010-04-17 06:13:15 +00003908 AddToWorkList(SmallShift.getNode());
3909 return DAG.getNode(ISD::ANY_EXTEND, N->getDebugLoc(), VT, SmallShift);
3910 }
Chris Lattner06afe072006-05-05 22:53:17 +00003911 }
Scott Michelfdc40a02009-02-17 22:15:04 +00003912
Chris Lattner3657ffe2006-10-12 20:23:19 +00003913 // fold (srl (sra X, Y), 31) -> (srl X, 31). This srl only looks at the sign
3914 // bit, which is unmodified by sra.
Bill Wendling88103372009-01-30 21:37:17 +00003915 if (N1C && N1C->getZExtValue() + 1 == VT.getSizeInBits()) {
Chris Lattner3657ffe2006-10-12 20:23:19 +00003916 if (N0.getOpcode() == ISD::SRA)
Bill Wendling88103372009-01-30 21:37:17 +00003917 return DAG.getNode(ISD::SRL, N->getDebugLoc(), VT, N0.getOperand(0), N1);
Chris Lattner3657ffe2006-10-12 20:23:19 +00003918 }
Scott Michelfdc40a02009-02-17 22:15:04 +00003919
Sylvestre Ledru94c22712012-09-27 10:14:43 +00003920 // fold (srl (ctlz x), "5") -> x iff x has one bit set (the low bit).
Scott Michelfdc40a02009-02-17 22:15:04 +00003921 if (N1C && N0.getOpcode() == ISD::CTLZ &&
Duncan Sands83ec4b62008-06-06 12:08:01 +00003922 N1C->getAPIntValue() == Log2_32(VT.getSizeInBits())) {
Dan Gohman948d8ea2008-02-20 16:33:30 +00003923 APInt KnownZero, KnownOne;
Rafael Espindola26c8dcc2012-04-04 12:51:34 +00003924 DAG.ComputeMaskedBits(N0.getOperand(0), KnownZero, KnownOne);
Scott Michelfdc40a02009-02-17 22:15:04 +00003925
Chris Lattner350bec02006-04-02 06:11:11 +00003926 // If any of the input bits are KnownOne, then the input couldn't be all
3927 // zeros, thus the result of the srl will always be zero.
Dan Gohman948d8ea2008-02-20 16:33:30 +00003928 if (KnownOne.getBoolValue()) return DAG.getConstant(0, VT);
Scott Michelfdc40a02009-02-17 22:15:04 +00003929
Chris Lattner350bec02006-04-02 06:11:11 +00003930 // If all of the bits input the to ctlz node are known to be zero, then
3931 // the result of the ctlz is "32" and the result of the shift is one.
Rafael Espindola26c8dcc2012-04-04 12:51:34 +00003932 APInt UnknownBits = ~KnownZero;
Chris Lattner350bec02006-04-02 06:11:11 +00003933 if (UnknownBits == 0) return DAG.getConstant(1, VT);
Scott Michelfdc40a02009-02-17 22:15:04 +00003934
Chris Lattner350bec02006-04-02 06:11:11 +00003935 // Otherwise, check to see if there is exactly one bit input to the ctlz.
Bill Wendling88103372009-01-30 21:37:17 +00003936 if ((UnknownBits & (UnknownBits - 1)) == 0) {
Chris Lattner350bec02006-04-02 06:11:11 +00003937 // Okay, we know that only that the single bit specified by UnknownBits
Bill Wendling88103372009-01-30 21:37:17 +00003938 // could be set on input to the CTLZ node. If this bit is set, the SRL
3939 // will return 0, if it is clear, it returns 1. Change the CTLZ/SRL pair
3940 // to an SRL/XOR pair, which is likely to simplify more.
Dan Gohman948d8ea2008-02-20 16:33:30 +00003941 unsigned ShAmt = UnknownBits.countTrailingZeros();
Dan Gohman475871a2008-07-27 21:46:04 +00003942 SDValue Op = N0.getOperand(0);
Bill Wendling88103372009-01-30 21:37:17 +00003943
Chris Lattner350bec02006-04-02 06:11:11 +00003944 if (ShAmt) {
Bill Wendling88103372009-01-30 21:37:17 +00003945 Op = DAG.getNode(ISD::SRL, N0.getDebugLoc(), VT, Op,
Owen Anderson95771af2011-02-25 21:41:48 +00003946 DAG.getConstant(ShAmt, getShiftAmountTy(Op.getValueType())));
Gabor Greifba36cb52008-08-28 21:40:38 +00003947 AddToWorkList(Op.getNode());
Chris Lattner350bec02006-04-02 06:11:11 +00003948 }
Bill Wendling88103372009-01-30 21:37:17 +00003949
3950 return DAG.getNode(ISD::XOR, N->getDebugLoc(), VT,
3951 Op, DAG.getConstant(1, VT));
Chris Lattner350bec02006-04-02 06:11:11 +00003952 }
3953 }
Evan Chengeb9f8922008-08-30 02:03:58 +00003954
Duncan Sandsb0d5cdd2009-02-01 18:06:53 +00003955 // fold (srl x, (trunc (and y, c))) -> (srl x, (and (trunc y), (trunc c))).
Evan Chengeb9f8922008-08-30 02:03:58 +00003956 if (N1.getOpcode() == ISD::TRUNCATE &&
Evan Cheng242ebd12008-09-22 18:19:24 +00003957 N1.getOperand(0).getOpcode() == ISD::AND &&
3958 N1.hasOneUse() && N1.getOperand(0).hasOneUse()) {
Evan Chengeb9f8922008-08-30 02:03:58 +00003959 SDValue N101 = N1.getOperand(0).getOperand(1);
Evan Cheng242ebd12008-09-22 18:19:24 +00003960 if (ConstantSDNode *N101C = dyn_cast<ConstantSDNode>(N101)) {
Owen Andersone50ed302009-08-10 22:56:29 +00003961 EVT TruncVT = N1.getValueType();
Evan Cheng242ebd12008-09-22 18:19:24 +00003962 SDValue N100 = N1.getOperand(0).getOperand(0);
Duncan Sandsb0d5cdd2009-02-01 18:06:53 +00003963 APInt TruncC = N101C->getAPIntValue();
Jay Foad40f8f622010-12-07 08:25:19 +00003964 TruncC = TruncC.trunc(TruncVT.getSizeInBits());
Bill Wendling88103372009-01-30 21:37:17 +00003965 return DAG.getNode(ISD::SRL, N->getDebugLoc(), VT, N0,
Bill Wendling9729c5a2009-01-31 03:12:48 +00003966 DAG.getNode(ISD::AND, N->getDebugLoc(),
Bill Wendling88103372009-01-30 21:37:17 +00003967 TruncVT,
Bill Wendling9729c5a2009-01-31 03:12:48 +00003968 DAG.getNode(ISD::TRUNCATE,
3969 N->getDebugLoc(),
3970 TruncVT, N100),
Dan Gohmance9bc122009-01-27 20:39:34 +00003971 DAG.getConstant(TruncC, TruncVT)));
Evan Chengeb9f8922008-08-30 02:03:58 +00003972 }
3973 }
Scott Michelfdc40a02009-02-17 22:15:04 +00003974
Chris Lattner61a4c072007-04-18 03:06:49 +00003975 // fold operands of srl based on knowledge that the low bits are not
3976 // demanded.
Dan Gohman475871a2008-07-27 21:46:04 +00003977 if (N1C && SimplifyDemandedBits(SDValue(N, 0)))
3978 return SDValue(N, 0);
Scott Michelfdc40a02009-02-17 22:15:04 +00003979
Evan Cheng9ab2b982009-12-18 21:31:31 +00003980 if (N1C) {
3981 SDValue NewSRL = visitShiftByConstant(N, N1C->getZExtValue());
3982 if (NewSRL.getNode())
3983 return NewSRL;
3984 }
3985
Dan Gohman4e39e9d2010-06-24 14:30:44 +00003986 // Attempt to convert a srl of a load into a narrower zero-extending load.
3987 SDValue NarrowLoad = ReduceLoadWidth(N);
3988 if (NarrowLoad.getNode())
3989 return NarrowLoad;
3990
Evan Cheng9ab2b982009-12-18 21:31:31 +00003991 // Here is a common situation. We want to optimize:
3992 //
3993 // %a = ...
3994 // %b = and i32 %a, 2
3995 // %c = srl i32 %b, 1
3996 // brcond i32 %c ...
3997 //
3998 // into
Wesley Peckbf17cfa2010-11-23 03:31:01 +00003999 //
Evan Cheng9ab2b982009-12-18 21:31:31 +00004000 // %a = ...
4001 // %b = and %a, 2
4002 // %c = setcc eq %b, 0
4003 // brcond %c ...
4004 //
4005 // However when after the source operand of SRL is optimized into AND, the SRL
4006 // itself may not be optimized further. Look for it and add the BRCOND into
4007 // the worklist.
Evan Chengd40d03e2010-01-06 19:38:29 +00004008 if (N->hasOneUse()) {
4009 SDNode *Use = *N->use_begin();
4010 if (Use->getOpcode() == ISD::BRCOND)
4011 AddToWorkList(Use);
4012 else if (Use->getOpcode() == ISD::TRUNCATE && Use->hasOneUse()) {
4013 // Also look pass the truncate.
4014 Use = *Use->use_begin();
4015 if (Use->getOpcode() == ISD::BRCOND)
4016 AddToWorkList(Use);
4017 }
4018 }
Evan Cheng9ab2b982009-12-18 21:31:31 +00004019
Evan Chengb3a3d5e2010-04-28 07:10:39 +00004020 return SDValue();
Evan Cheng4c26e932010-04-19 19:29:22 +00004021}
4022
Dan Gohman475871a2008-07-27 21:46:04 +00004023SDValue DAGCombiner::visitCTLZ(SDNode *N) {
4024 SDValue N0 = N->getOperand(0);
Owen Andersone50ed302009-08-10 22:56:29 +00004025 EVT VT = N->getValueType(0);
Nate Begeman1d4d4142005-09-01 00:19:25 +00004026
4027 // fold (ctlz c1) -> c2
Chris Lattner310b5782006-05-06 23:06:26 +00004028 if (isa<ConstantSDNode>(N0))
Bill Wendling34584e62009-01-30 22:02:18 +00004029 return DAG.getNode(ISD::CTLZ, N->getDebugLoc(), VT, N0);
Dan Gohman475871a2008-07-27 21:46:04 +00004030 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00004031}
4032
Chandler Carruth63974b22011-12-13 01:56:10 +00004033SDValue DAGCombiner::visitCTLZ_ZERO_UNDEF(SDNode *N) {
4034 SDValue N0 = N->getOperand(0);
4035 EVT VT = N->getValueType(0);
4036
4037 // fold (ctlz_zero_undef c1) -> c2
4038 if (isa<ConstantSDNode>(N0))
4039 return DAG.getNode(ISD::CTLZ_ZERO_UNDEF, N->getDebugLoc(), VT, N0);
4040 return SDValue();
4041}
4042
Dan Gohman475871a2008-07-27 21:46:04 +00004043SDValue DAGCombiner::visitCTTZ(SDNode *N) {
4044 SDValue N0 = N->getOperand(0);
Owen Andersone50ed302009-08-10 22:56:29 +00004045 EVT VT = N->getValueType(0);
Scott Michelfdc40a02009-02-17 22:15:04 +00004046
Nate Begeman1d4d4142005-09-01 00:19:25 +00004047 // fold (cttz c1) -> c2
Chris Lattner310b5782006-05-06 23:06:26 +00004048 if (isa<ConstantSDNode>(N0))
Bill Wendling34584e62009-01-30 22:02:18 +00004049 return DAG.getNode(ISD::CTTZ, N->getDebugLoc(), VT, N0);
Dan Gohman475871a2008-07-27 21:46:04 +00004050 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00004051}
4052
Chandler Carruth63974b22011-12-13 01:56:10 +00004053SDValue DAGCombiner::visitCTTZ_ZERO_UNDEF(SDNode *N) {
4054 SDValue N0 = N->getOperand(0);
4055 EVT VT = N->getValueType(0);
4056
4057 // fold (cttz_zero_undef c1) -> c2
4058 if (isa<ConstantSDNode>(N0))
4059 return DAG.getNode(ISD::CTTZ_ZERO_UNDEF, N->getDebugLoc(), VT, N0);
4060 return SDValue();
4061}
4062
Dan Gohman475871a2008-07-27 21:46:04 +00004063SDValue DAGCombiner::visitCTPOP(SDNode *N) {
4064 SDValue N0 = N->getOperand(0);
Owen Andersone50ed302009-08-10 22:56:29 +00004065 EVT VT = N->getValueType(0);
Scott Michelfdc40a02009-02-17 22:15:04 +00004066
Nate Begeman1d4d4142005-09-01 00:19:25 +00004067 // fold (ctpop c1) -> c2
Chris Lattner310b5782006-05-06 23:06:26 +00004068 if (isa<ConstantSDNode>(N0))
Bill Wendling34584e62009-01-30 22:02:18 +00004069 return DAG.getNode(ISD::CTPOP, N->getDebugLoc(), VT, N0);
Dan Gohman475871a2008-07-27 21:46:04 +00004070 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00004071}
4072
Dan Gohman475871a2008-07-27 21:46:04 +00004073SDValue DAGCombiner::visitSELECT(SDNode *N) {
4074 SDValue N0 = N->getOperand(0);
4075 SDValue N1 = N->getOperand(1);
4076 SDValue N2 = N->getOperand(2);
Nate Begeman452d7beb2005-09-16 00:54:12 +00004077 ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0);
4078 ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1);
4079 ConstantSDNode *N2C = dyn_cast<ConstantSDNode>(N2);
Owen Andersone50ed302009-08-10 22:56:29 +00004080 EVT VT = N->getValueType(0);
4081 EVT VT0 = N0.getValueType();
Nate Begeman44728a72005-09-19 22:34:01 +00004082
Bill Wendling34584e62009-01-30 22:02:18 +00004083 // fold (select C, X, X) -> X
Nate Begeman452d7beb2005-09-16 00:54:12 +00004084 if (N1 == N2)
4085 return N1;
Bill Wendling34584e62009-01-30 22:02:18 +00004086 // fold (select true, X, Y) -> X
Nate Begeman452d7beb2005-09-16 00:54:12 +00004087 if (N0C && !N0C->isNullValue())
4088 return N1;
Bill Wendling34584e62009-01-30 22:02:18 +00004089 // fold (select false, X, Y) -> Y
Nate Begeman452d7beb2005-09-16 00:54:12 +00004090 if (N0C && N0C->isNullValue())
4091 return N2;
Bill Wendling34584e62009-01-30 22:02:18 +00004092 // fold (select C, 1, X) -> (or C, X)
Owen Anderson825b72b2009-08-11 20:47:22 +00004093 if (VT == MVT::i1 && N1C && N1C->getAPIntValue() == 1)
Bill Wendling34584e62009-01-30 22:02:18 +00004094 return DAG.getNode(ISD::OR, N->getDebugLoc(), VT, N0, N2);
4095 // fold (select C, 0, 1) -> (xor C, 1)
Bob Wilson67ba2232009-01-22 22:05:48 +00004096 if (VT.isInteger() &&
Owen Anderson825b72b2009-08-11 20:47:22 +00004097 (VT0 == MVT::i1 ||
Bob Wilson67ba2232009-01-22 22:05:48 +00004098 (VT0.isInteger() &&
Nadav Rotem6dfabb62012-09-20 08:53:31 +00004099 TLI.getBooleanContents(false) ==
4100 TargetLowering::ZeroOrOneBooleanContent)) &&
Dan Gohman002e5d02008-03-13 22:13:53 +00004101 N1C && N2C && N1C->isNullValue() && N2C->getAPIntValue() == 1) {
Bill Wendling34584e62009-01-30 22:02:18 +00004102 SDValue XORNode;
Evan Cheng571c4782007-08-18 05:57:05 +00004103 if (VT == VT0)
Bill Wendling34584e62009-01-30 22:02:18 +00004104 return DAG.getNode(ISD::XOR, N->getDebugLoc(), VT0,
4105 N0, DAG.getConstant(1, VT0));
4106 XORNode = DAG.getNode(ISD::XOR, N0.getDebugLoc(), VT0,
4107 N0, DAG.getConstant(1, VT0));
Gabor Greifba36cb52008-08-28 21:40:38 +00004108 AddToWorkList(XORNode.getNode());
Duncan Sands8e4eb092008-06-08 20:54:56 +00004109 if (VT.bitsGT(VT0))
Bill Wendling34584e62009-01-30 22:02:18 +00004110 return DAG.getNode(ISD::ZERO_EXTEND, N->getDebugLoc(), VT, XORNode);
4111 return DAG.getNode(ISD::TRUNCATE, N->getDebugLoc(), VT, XORNode);
Evan Cheng571c4782007-08-18 05:57:05 +00004112 }
Bill Wendling34584e62009-01-30 22:02:18 +00004113 // fold (select C, 0, X) -> (and (not C), X)
Owen Anderson825b72b2009-08-11 20:47:22 +00004114 if (VT == VT0 && VT == MVT::i1 && N1C && N1C->isNullValue()) {
Bill Wendling7581bfa2009-01-30 23:03:19 +00004115 SDValue NOTNode = DAG.getNOT(N0.getDebugLoc(), N0, VT);
Bob Wilson4c245462009-01-22 17:39:32 +00004116 AddToWorkList(NOTNode.getNode());
Bill Wendling7581bfa2009-01-30 23:03:19 +00004117 return DAG.getNode(ISD::AND, N->getDebugLoc(), VT, NOTNode, N2);
Nate Begeman452d7beb2005-09-16 00:54:12 +00004118 }
Bill Wendling34584e62009-01-30 22:02:18 +00004119 // fold (select C, X, 1) -> (or (not C), X)
Owen Anderson825b72b2009-08-11 20:47:22 +00004120 if (VT == VT0 && VT == MVT::i1 && N2C && N2C->getAPIntValue() == 1) {
Bill Wendling34584e62009-01-30 22:02:18 +00004121 SDValue NOTNode = DAG.getNOT(N0.getDebugLoc(), N0, VT);
Bob Wilson4c245462009-01-22 17:39:32 +00004122 AddToWorkList(NOTNode.getNode());
Bill Wendling7581bfa2009-01-30 23:03:19 +00004123 return DAG.getNode(ISD::OR, N->getDebugLoc(), VT, NOTNode, N1);
Nate Begeman452d7beb2005-09-16 00:54:12 +00004124 }
Bill Wendling34584e62009-01-30 22:02:18 +00004125 // fold (select C, X, 0) -> (and C, X)
Owen Anderson825b72b2009-08-11 20:47:22 +00004126 if (VT == MVT::i1 && N2C && N2C->isNullValue())
Bill Wendling34584e62009-01-30 22:02:18 +00004127 return DAG.getNode(ISD::AND, N->getDebugLoc(), VT, N0, N1);
4128 // fold (select X, X, Y) -> (or X, Y)
4129 // fold (select X, 1, Y) -> (or X, Y)
Owen Anderson825b72b2009-08-11 20:47:22 +00004130 if (VT == MVT::i1 && (N0 == N1 || (N1C && N1C->getAPIntValue() == 1)))
Bill Wendling34584e62009-01-30 22:02:18 +00004131 return DAG.getNode(ISD::OR, N->getDebugLoc(), VT, N0, N2);
4132 // fold (select X, Y, X) -> (and X, Y)
4133 // fold (select X, Y, 0) -> (and X, Y)
Owen Anderson825b72b2009-08-11 20:47:22 +00004134 if (VT == MVT::i1 && (N0 == N2 || (N2C && N2C->getAPIntValue() == 0)))
Bill Wendling34584e62009-01-30 22:02:18 +00004135 return DAG.getNode(ISD::AND, N->getDebugLoc(), VT, N0, N1);
Scott Michelfdc40a02009-02-17 22:15:04 +00004136
Chris Lattner40c62d52005-10-18 06:04:22 +00004137 // If we can fold this based on the true/false value, do so.
4138 if (SimplifySelectOps(N, N1, N2))
Dan Gohman475871a2008-07-27 21:46:04 +00004139 return SDValue(N, 0); // Don't revisit N.
Duncan Sandsd4b9c172008-06-13 19:07:40 +00004140
Nate Begeman44728a72005-09-19 22:34:01 +00004141 // fold selects based on a setcc into other things, such as min/max/abs
Anton Korobeynikov4c71dfe2008-02-20 11:10:28 +00004142 if (N0.getOpcode() == ISD::SETCC) {
Nate Begeman750ac1b2006-02-01 07:19:44 +00004143 // FIXME:
Owen Anderson825b72b2009-08-11 20:47:22 +00004144 // Check against MVT::Other for SELECT_CC, which is a workaround for targets
Nate Begeman750ac1b2006-02-01 07:19:44 +00004145 // having to say they don't support SELECT_CC on every type the DAG knows
4146 // about, since there is no way to mark an opcode illegal at all value types
Owen Anderson825b72b2009-08-11 20:47:22 +00004147 if (TLI.isOperationLegalOrCustom(ISD::SELECT_CC, MVT::Other) &&
Dan Gohman4ea48042009-08-02 16:19:38 +00004148 TLI.isOperationLegalOrCustom(ISD::SELECT_CC, VT))
Bill Wendling34584e62009-01-30 22:02:18 +00004149 return DAG.getNode(ISD::SELECT_CC, N->getDebugLoc(), VT,
4150 N0.getOperand(0), N0.getOperand(1),
Nate Begeman750ac1b2006-02-01 07:19:44 +00004151 N1, N2, N0.getOperand(2));
Chris Lattner600fec32009-03-11 05:08:08 +00004152 return SimplifySelect(N->getDebugLoc(), N0, N1, N2);
Anton Korobeynikov4c71dfe2008-02-20 11:10:28 +00004153 }
Bill Wendling34584e62009-01-30 22:02:18 +00004154
Dan Gohman475871a2008-07-27 21:46:04 +00004155 return SDValue();
Nate Begeman452d7beb2005-09-16 00:54:12 +00004156}
4157
Dan Gohman475871a2008-07-27 21:46:04 +00004158SDValue DAGCombiner::visitSELECT_CC(SDNode *N) {
4159 SDValue N0 = N->getOperand(0);
4160 SDValue N1 = N->getOperand(1);
4161 SDValue N2 = N->getOperand(2);
4162 SDValue N3 = N->getOperand(3);
4163 SDValue N4 = N->getOperand(4);
Nate Begeman44728a72005-09-19 22:34:01 +00004164 ISD::CondCode CC = cast<CondCodeSDNode>(N4)->get();
Scott Michelfdc40a02009-02-17 22:15:04 +00004165
Nate Begeman44728a72005-09-19 22:34:01 +00004166 // fold select_cc lhs, rhs, x, x, cc -> x
4167 if (N2 == N3)
4168 return N2;
Scott Michelfdc40a02009-02-17 22:15:04 +00004169
Chris Lattner5f42a242006-09-20 06:19:26 +00004170 // Determine if the condition we're dealing with is constant
Duncan Sands5480c042009-01-01 15:52:00 +00004171 SDValue SCC = SimplifySetCC(TLI.getSetCCResultType(N0.getValueType()),
Dale Johannesenff97d4f2009-02-03 00:47:48 +00004172 N0, N1, CC, N->getDebugLoc(), false);
Gabor Greifba36cb52008-08-28 21:40:38 +00004173 if (SCC.getNode()) AddToWorkList(SCC.getNode());
Chris Lattner5f42a242006-09-20 06:19:26 +00004174
Gabor Greifba36cb52008-08-28 21:40:38 +00004175 if (ConstantSDNode *SCCC = dyn_cast_or_null<ConstantSDNode>(SCC.getNode())) {
Dan Gohman002e5d02008-03-13 22:13:53 +00004176 if (!SCCC->isNullValue())
Chris Lattner5f42a242006-09-20 06:19:26 +00004177 return N2; // cond always true -> true val
4178 else
4179 return N3; // cond always false -> false val
4180 }
Scott Michelfdc40a02009-02-17 22:15:04 +00004181
Chris Lattner5f42a242006-09-20 06:19:26 +00004182 // Fold to a simpler select_cc
Gabor Greifba36cb52008-08-28 21:40:38 +00004183 if (SCC.getNode() && SCC.getOpcode() == ISD::SETCC)
Scott Michelfdc40a02009-02-17 22:15:04 +00004184 return DAG.getNode(ISD::SELECT_CC, N->getDebugLoc(), N2.getValueType(),
4185 SCC.getOperand(0), SCC.getOperand(1), N2, N3,
Chris Lattner5f42a242006-09-20 06:19:26 +00004186 SCC.getOperand(2));
Scott Michelfdc40a02009-02-17 22:15:04 +00004187
Chris Lattner40c62d52005-10-18 06:04:22 +00004188 // If we can fold this based on the true/false value, do so.
4189 if (SimplifySelectOps(N, N2, N3))
Dan Gohman475871a2008-07-27 21:46:04 +00004190 return SDValue(N, 0); // Don't revisit N.
Scott Michelfdc40a02009-02-17 22:15:04 +00004191
Nate Begeman44728a72005-09-19 22:34:01 +00004192 // fold select_cc into other things, such as min/max/abs
Bill Wendling836ca7d2009-01-30 23:59:18 +00004193 return SimplifySelectCC(N->getDebugLoc(), N0, N1, N2, N3, CC);
Nate Begeman452d7beb2005-09-16 00:54:12 +00004194}
4195
Dan Gohman475871a2008-07-27 21:46:04 +00004196SDValue DAGCombiner::visitSETCC(SDNode *N) {
Nate Begeman452d7beb2005-09-16 00:54:12 +00004197 return SimplifySetCC(N->getValueType(0), N->getOperand(0), N->getOperand(1),
Dale Johannesenff97d4f2009-02-03 00:47:48 +00004198 cast<CondCodeSDNode>(N->getOperand(2))->get(),
4199 N->getDebugLoc());
Nate Begeman452d7beb2005-09-16 00:54:12 +00004200}
4201
Evan Cheng3c3ddb32007-10-29 19:58:20 +00004202// ExtendUsesToFormExtLoad - Trying to extend uses of a load to enable this:
Dan Gohman57fc82d2009-04-09 03:51:29 +00004203// "fold ({s|z|a}ext (load x)) -> ({s|z|a}ext (truncate ({s|z|a}extload x)))"
Evan Cheng3c3ddb32007-10-29 19:58:20 +00004204// transformation. Returns true if extension are possible and the above
Scott Michelfdc40a02009-02-17 22:15:04 +00004205// mentioned transformation is profitable.
Dan Gohman475871a2008-07-27 21:46:04 +00004206static bool ExtendUsesToFormExtLoad(SDNode *N, SDValue N0,
Evan Cheng3c3ddb32007-10-29 19:58:20 +00004207 unsigned ExtOpc,
4208 SmallVector<SDNode*, 4> &ExtendNodes,
Dan Gohman79ce2762009-01-15 19:20:50 +00004209 const TargetLowering &TLI) {
Evan Cheng3c3ddb32007-10-29 19:58:20 +00004210 bool HasCopyToRegUses = false;
4211 bool isTruncFree = TLI.isTruncateFree(N->getValueType(0), N0.getValueType());
Gabor Greif12632d22008-08-30 19:29:20 +00004212 for (SDNode::use_iterator UI = N0.getNode()->use_begin(),
4213 UE = N0.getNode()->use_end();
Evan Cheng3c3ddb32007-10-29 19:58:20 +00004214 UI != UE; ++UI) {
Dan Gohman89684502008-07-27 20:43:25 +00004215 SDNode *User = *UI;
Evan Cheng3c3ddb32007-10-29 19:58:20 +00004216 if (User == N)
4217 continue;
Dan Gohman57fc82d2009-04-09 03:51:29 +00004218 if (UI.getUse().getResNo() != N0.getResNo())
4219 continue;
Evan Cheng3c3ddb32007-10-29 19:58:20 +00004220 // FIXME: Only extend SETCC N, N and SETCC N, c for now.
Dan Gohman57fc82d2009-04-09 03:51:29 +00004221 if (ExtOpc != ISD::ANY_EXTEND && User->getOpcode() == ISD::SETCC) {
Evan Cheng3c3ddb32007-10-29 19:58:20 +00004222 ISD::CondCode CC = cast<CondCodeSDNode>(User->getOperand(2))->get();
4223 if (ExtOpc == ISD::ZERO_EXTEND && ISD::isSignedIntSetCC(CC))
4224 // Sign bits will be lost after a zext.
4225 return false;
4226 bool Add = false;
4227 for (unsigned i = 0; i != 2; ++i) {
Dan Gohman475871a2008-07-27 21:46:04 +00004228 SDValue UseOp = User->getOperand(i);
Evan Cheng3c3ddb32007-10-29 19:58:20 +00004229 if (UseOp == N0)
4230 continue;
4231 if (!isa<ConstantSDNode>(UseOp))
4232 return false;
4233 Add = true;
4234 }
4235 if (Add)
4236 ExtendNodes.push_back(User);
Dan Gohman57fc82d2009-04-09 03:51:29 +00004237 continue;
Evan Cheng3c3ddb32007-10-29 19:58:20 +00004238 }
Dan Gohman57fc82d2009-04-09 03:51:29 +00004239 // If truncates aren't free and there are users we can't
4240 // extend, it isn't worthwhile.
4241 if (!isTruncFree)
4242 return false;
4243 // Remember if this value is live-out.
4244 if (User->getOpcode() == ISD::CopyToReg)
4245 HasCopyToRegUses = true;
Evan Cheng3c3ddb32007-10-29 19:58:20 +00004246 }
4247
4248 if (HasCopyToRegUses) {
4249 bool BothLiveOut = false;
4250 for (SDNode::use_iterator UI = N->use_begin(), UE = N->use_end();
4251 UI != UE; ++UI) {
Dan Gohman57fc82d2009-04-09 03:51:29 +00004252 SDUse &Use = UI.getUse();
4253 if (Use.getResNo() == 0 && Use.getUser()->getOpcode() == ISD::CopyToReg) {
4254 BothLiveOut = true;
4255 break;
Evan Cheng3c3ddb32007-10-29 19:58:20 +00004256 }
4257 }
4258 if (BothLiveOut)
4259 // Both unextended and extended values are live out. There had better be
Bob Wilsonbebfbc52010-11-28 06:51:19 +00004260 // a good reason for the transformation.
Evan Cheng3c3ddb32007-10-29 19:58:20 +00004261 return ExtendNodes.size();
4262 }
4263 return true;
4264}
4265
Nick Lewyckyc06b5bf2011-06-16 01:15:49 +00004266void DAGCombiner::ExtendSetCCUses(SmallVector<SDNode*, 4> SetCCs,
4267 SDValue Trunc, SDValue ExtLoad, DebugLoc DL,
4268 ISD::NodeType ExtType) {
4269 // Extend SetCC uses if necessary.
4270 for (unsigned i = 0, e = SetCCs.size(); i != e; ++i) {
4271 SDNode *SetCC = SetCCs[i];
4272 SmallVector<SDValue, 4> Ops;
4273
4274 for (unsigned j = 0; j != 2; ++j) {
4275 SDValue SOp = SetCC->getOperand(j);
4276 if (SOp == Trunc)
4277 Ops.push_back(ExtLoad);
4278 else
4279 Ops.push_back(DAG.getNode(ExtType, DL, ExtLoad->getValueType(0), SOp));
4280 }
4281
4282 Ops.push_back(SetCC->getOperand(2));
4283 CombineTo(SetCC, DAG.getNode(ISD::SETCC, DL, SetCC->getValueType(0),
4284 &Ops[0], Ops.size()));
4285 }
4286}
4287
Dan Gohman475871a2008-07-27 21:46:04 +00004288SDValue DAGCombiner::visitSIGN_EXTEND(SDNode *N) {
4289 SDValue N0 = N->getOperand(0);
Owen Andersone50ed302009-08-10 22:56:29 +00004290 EVT VT = N->getValueType(0);
Nate Begeman1d4d4142005-09-01 00:19:25 +00004291
Nate Begeman1d4d4142005-09-01 00:19:25 +00004292 // fold (sext c1) -> c1
Reid Spencer3ed469c2006-11-02 20:25:50 +00004293 if (isa<ConstantSDNode>(N0))
Bill Wendling6ce610f2009-01-30 22:23:15 +00004294 return DAG.getNode(ISD::SIGN_EXTEND, N->getDebugLoc(), VT, N0);
Scott Michelfdc40a02009-02-17 22:15:04 +00004295
Nate Begeman1d4d4142005-09-01 00:19:25 +00004296 // fold (sext (sext x)) -> (sext x)
Chris Lattner310b5782006-05-06 23:06:26 +00004297 // fold (sext (aext x)) -> (sext x)
4298 if (N0.getOpcode() == ISD::SIGN_EXTEND || N0.getOpcode() == ISD::ANY_EXTEND)
Bill Wendling6ce610f2009-01-30 22:23:15 +00004299 return DAG.getNode(ISD::SIGN_EXTEND, N->getDebugLoc(), VT,
4300 N0.getOperand(0));
Scott Michelfdc40a02009-02-17 22:15:04 +00004301
Chris Lattner22558872007-02-26 03:13:59 +00004302 if (N0.getOpcode() == ISD::TRUNCATE) {
Dan Gohman1fdfa6a2008-05-20 20:56:33 +00004303 // fold (sext (truncate (load x))) -> (sext (smaller load x))
4304 // fold (sext (truncate (srl (load x), c))) -> (sext (smaller load (x+c/n)))
Gabor Greifba36cb52008-08-28 21:40:38 +00004305 SDValue NarrowLoad = ReduceLoadWidth(N0.getNode());
4306 if (NarrowLoad.getNode()) {
Dale Johannesen61734eb2010-05-25 17:50:03 +00004307 SDNode* oye = N0.getNode()->getOperand(0).getNode();
4308 if (NarrowLoad.getNode() != N0.getNode()) {
Gabor Greifba36cb52008-08-28 21:40:38 +00004309 CombineTo(N0.getNode(), NarrowLoad);
Dale Johannesen61734eb2010-05-25 17:50:03 +00004310 // CombineTo deleted the truncate, if needed, but not what's under it.
4311 AddToWorkList(oye);
4312 }
Dan Gohmanc7b34442009-04-27 02:00:55 +00004313 return SDValue(N, 0); // Return N so it doesn't get rechecked!
Evan Cheng0b063de2007-03-23 02:16:52 +00004314 }
Evan Chengc88138f2007-03-22 01:54:19 +00004315
Dan Gohman1fdfa6a2008-05-20 20:56:33 +00004316 // See if the value being truncated is already sign extended. If so, just
4317 // eliminate the trunc/sext pair.
Dan Gohman475871a2008-07-27 21:46:04 +00004318 SDValue Op = N0.getOperand(0);
Dan Gohmand1996362010-01-09 02:13:55 +00004319 unsigned OpBits = Op.getValueType().getScalarType().getSizeInBits();
4320 unsigned MidBits = N0.getValueType().getScalarType().getSizeInBits();
4321 unsigned DestBits = VT.getScalarType().getSizeInBits();
Dan Gohmanea859be2007-06-22 14:59:07 +00004322 unsigned NumSignBits = DAG.ComputeNumSignBits(Op);
Scott Michelfdc40a02009-02-17 22:15:04 +00004323
Chris Lattner22558872007-02-26 03:13:59 +00004324 if (OpBits == DestBits) {
4325 // Op is i32, Mid is i8, and Dest is i32. If Op has more than 24 sign
4326 // bits, it is already ready.
4327 if (NumSignBits > DestBits-MidBits)
4328 return Op;
4329 } else if (OpBits < DestBits) {
4330 // Op is i32, Mid is i8, and Dest is i64. If Op has more than 24 sign
4331 // bits, just sext from i32.
4332 if (NumSignBits > OpBits-MidBits)
Bill Wendling6ce610f2009-01-30 22:23:15 +00004333 return DAG.getNode(ISD::SIGN_EXTEND, N->getDebugLoc(), VT, Op);
Chris Lattner22558872007-02-26 03:13:59 +00004334 } else {
4335 // Op is i64, Mid is i8, and Dest is i32. If Op has more than 56 sign
4336 // bits, just truncate to i32.
4337 if (NumSignBits > OpBits-MidBits)
Bill Wendling6ce610f2009-01-30 22:23:15 +00004338 return DAG.getNode(ISD::TRUNCATE, N->getDebugLoc(), VT, Op);
Chris Lattner6007b842006-09-21 06:00:20 +00004339 }
Scott Michelfdc40a02009-02-17 22:15:04 +00004340
Chris Lattner22558872007-02-26 03:13:59 +00004341 // fold (sext (truncate x)) -> (sextinreg x).
Duncan Sands25cf2272008-11-24 14:53:14 +00004342 if (!LegalOperations || TLI.isOperationLegal(ISD::SIGN_EXTEND_INREG,
4343 N0.getValueType())) {
Dan Gohmand1996362010-01-09 02:13:55 +00004344 if (OpBits < DestBits)
Bill Wendling6ce610f2009-01-30 22:23:15 +00004345 Op = DAG.getNode(ISD::ANY_EXTEND, N0.getDebugLoc(), VT, Op);
Dan Gohmand1996362010-01-09 02:13:55 +00004346 else if (OpBits > DestBits)
Bill Wendling6ce610f2009-01-30 22:23:15 +00004347 Op = DAG.getNode(ISD::TRUNCATE, N0.getDebugLoc(), VT, Op);
4348 return DAG.getNode(ISD::SIGN_EXTEND_INREG, N->getDebugLoc(), VT, Op,
Dan Gohmand1996362010-01-09 02:13:55 +00004349 DAG.getValueType(N0.getValueType()));
Chris Lattner22558872007-02-26 03:13:59 +00004350 }
Chris Lattner6007b842006-09-21 06:00:20 +00004351 }
Scott Michelfdc40a02009-02-17 22:15:04 +00004352
Evan Cheng110dec22005-12-14 02:19:23 +00004353 // fold (sext (load x)) -> (sext (truncate (sextload x)))
Nadav Rotem8c20ec52011-02-24 21:01:34 +00004354 // None of the supported targets knows how to perform load and sign extend
Nadav Rotemfcd96192011-02-27 07:40:43 +00004355 // on vectors in one instruction. We only perform this transformation on
4356 // scalars.
Nadav Rotem8c20ec52011-02-24 21:01:34 +00004357 if (ISD::isNON_EXTLoad(N0.getNode()) && !VT.isVector() &&
Duncan Sands25cf2272008-11-24 14:53:14 +00004358 ((!LegalOperations && !cast<LoadSDNode>(N0)->isVolatile()) ||
Evan Cheng03294662008-10-14 21:26:46 +00004359 TLI.isLoadExtLegal(ISD::SEXTLOAD, N0.getValueType()))) {
Evan Cheng3c3ddb32007-10-29 19:58:20 +00004360 bool DoXform = true;
4361 SmallVector<SDNode*, 4> SetCCs;
4362 if (!N0.hasOneUse())
4363 DoXform = ExtendUsesToFormExtLoad(N, N0, ISD::SIGN_EXTEND, SetCCs, TLI);
4364 if (DoXform) {
4365 LoadSDNode *LN0 = cast<LoadSDNode>(N0);
Stuart Hastingsa9011292011-02-16 16:23:55 +00004366 SDValue ExtLoad = DAG.getExtLoad(ISD::SEXTLOAD, N->getDebugLoc(), VT,
Dan Gohman57fc82d2009-04-09 03:51:29 +00004367 LN0->getChain(),
Chris Lattner3d6ccfb2010-09-21 17:04:51 +00004368 LN0->getBasePtr(), LN0->getPointerInfo(),
Duncan Sands25cf2272008-11-24 14:53:14 +00004369 N0.getValueType(),
David Greene1e559442010-02-15 17:00:31 +00004370 LN0->isVolatile(), LN0->isNonTemporal(),
4371 LN0->getAlignment());
Evan Cheng3c3ddb32007-10-29 19:58:20 +00004372 CombineTo(N, ExtLoad);
Bill Wendling6ce610f2009-01-30 22:23:15 +00004373 SDValue Trunc = DAG.getNode(ISD::TRUNCATE, N0.getDebugLoc(),
4374 N0.getValueType(), ExtLoad);
Gabor Greifba36cb52008-08-28 21:40:38 +00004375 CombineTo(N0.getNode(), Trunc, ExtLoad.getValue(1));
Nick Lewyckyc06b5bf2011-06-16 01:15:49 +00004376 ExtendSetCCUses(SetCCs, Trunc, ExtLoad, N->getDebugLoc(),
4377 ISD::SIGN_EXTEND);
Dan Gohman475871a2008-07-27 21:46:04 +00004378 return SDValue(N, 0); // Return N so it doesn't get rechecked!
Evan Cheng3c3ddb32007-10-29 19:58:20 +00004379 }
Nate Begeman3df4d522005-10-12 20:40:40 +00004380 }
Chris Lattnerad25d4e2005-12-14 19:05:06 +00004381
4382 // fold (sext (sextload x)) -> (sext (truncate (sextload x)))
4383 // fold (sext ( extload x)) -> (sext (truncate (sextload x)))
Gabor Greifba36cb52008-08-28 21:40:38 +00004384 if ((ISD::isSEXTLoad(N0.getNode()) || ISD::isEXTLoad(N0.getNode())) &&
4385 ISD::isUNINDEXEDLoad(N0.getNode()) && N0.hasOneUse()) {
Evan Cheng466685d2006-10-09 20:57:25 +00004386 LoadSDNode *LN0 = cast<LoadSDNode>(N0);
Dan Gohman8a55ce42009-09-23 21:02:20 +00004387 EVT MemVT = LN0->getMemoryVT();
Duncan Sands25cf2272008-11-24 14:53:14 +00004388 if ((!LegalOperations && !LN0->isVolatile()) ||
Dan Gohman8a55ce42009-09-23 21:02:20 +00004389 TLI.isLoadExtLegal(ISD::SEXTLOAD, MemVT)) {
Stuart Hastingsa9011292011-02-16 16:23:55 +00004390 SDValue ExtLoad = DAG.getExtLoad(ISD::SEXTLOAD, N->getDebugLoc(), VT,
Bill Wendling6ce610f2009-01-30 22:23:15 +00004391 LN0->getChain(),
Chris Lattner3d6ccfb2010-09-21 17:04:51 +00004392 LN0->getBasePtr(), LN0->getPointerInfo(),
4393 MemVT,
David Greene1e559442010-02-15 17:00:31 +00004394 LN0->isVolatile(), LN0->isNonTemporal(),
4395 LN0->getAlignment());
Jim Laskeyf6c4ccf2006-12-15 21:38:30 +00004396 CombineTo(N, ExtLoad);
Gabor Greif12632d22008-08-30 19:29:20 +00004397 CombineTo(N0.getNode(),
Bill Wendling6ce610f2009-01-30 22:23:15 +00004398 DAG.getNode(ISD::TRUNCATE, N0.getDebugLoc(),
4399 N0.getValueType(), ExtLoad),
Jim Laskeyf6c4ccf2006-12-15 21:38:30 +00004400 ExtLoad.getValue(1));
Dan Gohman475871a2008-07-27 21:46:04 +00004401 return SDValue(N, 0); // Return N so it doesn't get rechecked!
Jim Laskeyf6c4ccf2006-12-15 21:38:30 +00004402 }
Chris Lattnerad25d4e2005-12-14 19:05:06 +00004403 }
Scott Michelfdc40a02009-02-17 22:15:04 +00004404
Nick Lewyckyc06b5bf2011-06-16 01:15:49 +00004405 // fold (sext (and/or/xor (load x), cst)) ->
4406 // (and/or/xor (sextload x), (sext cst))
4407 if ((N0.getOpcode() == ISD::AND || N0.getOpcode() == ISD::OR ||
4408 N0.getOpcode() == ISD::XOR) &&
4409 isa<LoadSDNode>(N0.getOperand(0)) &&
4410 N0.getOperand(1).getOpcode() == ISD::Constant &&
4411 TLI.isLoadExtLegal(ISD::SEXTLOAD, N0.getValueType()) &&
4412 (!LegalOperations && TLI.isOperationLegal(N0.getOpcode(), VT))) {
4413 LoadSDNode *LN0 = cast<LoadSDNode>(N0.getOperand(0));
4414 if (LN0->getExtensionType() != ISD::ZEXTLOAD) {
4415 bool DoXform = true;
4416 SmallVector<SDNode*, 4> SetCCs;
4417 if (!N0.hasOneUse())
4418 DoXform = ExtendUsesToFormExtLoad(N, N0.getOperand(0), ISD::SIGN_EXTEND,
4419 SetCCs, TLI);
4420 if (DoXform) {
4421 SDValue ExtLoad = DAG.getExtLoad(ISD::SEXTLOAD, LN0->getDebugLoc(), VT,
4422 LN0->getChain(), LN0->getBasePtr(),
4423 LN0->getPointerInfo(),
4424 LN0->getMemoryVT(),
4425 LN0->isVolatile(),
4426 LN0->isNonTemporal(),
4427 LN0->getAlignment());
4428 APInt Mask = cast<ConstantSDNode>(N0.getOperand(1))->getAPIntValue();
4429 Mask = Mask.sext(VT.getSizeInBits());
4430 SDValue And = DAG.getNode(N0.getOpcode(), N->getDebugLoc(), VT,
4431 ExtLoad, DAG.getConstant(Mask, VT));
4432 SDValue Trunc = DAG.getNode(ISD::TRUNCATE,
4433 N0.getOperand(0).getDebugLoc(),
4434 N0.getOperand(0).getValueType(), ExtLoad);
4435 CombineTo(N, And);
4436 CombineTo(N0.getOperand(0).getNode(), Trunc, ExtLoad.getValue(1));
4437 ExtendSetCCUses(SetCCs, Trunc, ExtLoad, N->getDebugLoc(),
4438 ISD::SIGN_EXTEND);
4439 return SDValue(N, 0); // Return N so it doesn't get rechecked!
4440 }
4441 }
4442 }
4443
Chris Lattner20a35c32007-04-11 05:32:27 +00004444 if (N0.getOpcode() == ISD::SETCC) {
Chris Lattner2b7a2712009-07-08 00:31:33 +00004445 // sext(setcc) -> sext_in_reg(vsetcc) for vectors.
Dan Gohman3ce89f42010-04-30 17:19:19 +00004446 // Only do this before legalize for now.
4447 if (VT.isVector() && !LegalOperations) {
4448 EVT N0VT = N0.getOperand(0).getValueType();
Nadav Rotem2e506192012-04-11 08:26:11 +00004449 // On some architectures (such as SSE/NEON/etc) the SETCC result type is
4450 // of the same size as the compared operands. Only optimize sext(setcc())
4451 // if this is the case.
4452 EVT SVT = TLI.getSetCCResultType(N0VT);
4453
4454 // We know that the # elements of the results is the same as the
4455 // # elements of the compare (and the # elements of the compare result
4456 // for that matter). Check to see that they are the same size. If so,
4457 // we know that the element size of the sext'd result matches the
4458 // element size of the compare operands.
4459 if (VT.getSizeInBits() == SVT.getSizeInBits())
Duncan Sands28b77e92011-09-06 19:07:46 +00004460 return DAG.getSetCC(N->getDebugLoc(), VT, N0.getOperand(0),
Duncan Sands34727662010-07-12 08:16:59 +00004461 N0.getOperand(1),
4462 cast<CondCodeSDNode>(N0.getOperand(2))->get());
Dan Gohman3ce89f42010-04-30 17:19:19 +00004463 // If the desired elements are smaller or larger than the source
4464 // elements we can use a matching integer vector type and then
4465 // truncate/sign extend
Craig Topper0eb5dad2012-09-29 07:18:53 +00004466 EVT MatchingElementType =
4467 EVT::getIntegerVT(*DAG.getContext(),
4468 N0VT.getScalarType().getSizeInBits());
4469 EVT MatchingVectorType =
4470 EVT::getVectorVT(*DAG.getContext(), MatchingElementType,
4471 N0VT.getVectorNumElements());
Nadav Rotem2e506192012-04-11 08:26:11 +00004472
Craig Topper0eb5dad2012-09-29 07:18:53 +00004473 if (SVT == MatchingVectorType) {
4474 SDValue VsetCC = DAG.getSetCC(N->getDebugLoc(), MatchingVectorType,
4475 N0.getOperand(0), N0.getOperand(1),
4476 cast<CondCodeSDNode>(N0.getOperand(2))->get());
4477 return DAG.getSExtOrTrunc(VsetCC, N->getDebugLoc(), VT);
Dan Gohman3ce89f42010-04-30 17:19:19 +00004478 }
Chris Lattner2b7a2712009-07-08 00:31:33 +00004479 }
Dan Gohman3ce89f42010-04-30 17:19:19 +00004480
Chris Lattner2b7a2712009-07-08 00:31:33 +00004481 // sext(setcc x, y, cc) -> (select_cc x, y, -1, 0, cc)
Dan Gohmana7bcef12010-04-24 01:17:30 +00004482 unsigned ElementWidth = VT.getScalarType().getSizeInBits();
Dan Gohman5cbd37e2009-08-06 09:18:59 +00004483 SDValue NegOne =
Dan Gohmana7bcef12010-04-24 01:17:30 +00004484 DAG.getConstant(APInt::getAllOnesValue(ElementWidth), VT);
Scott Michelfdc40a02009-02-17 22:15:04 +00004485 SDValue SCC =
Bill Wendling836ca7d2009-01-30 23:59:18 +00004486 SimplifySelectCC(N->getDebugLoc(), N0.getOperand(0), N0.getOperand(1),
Dan Gohman5cbd37e2009-08-06 09:18:59 +00004487 NegOne, DAG.getConstant(0, VT),
Chris Lattner1eba01e2007-04-11 06:50:51 +00004488 cast<CondCodeSDNode>(N0.getOperand(2))->get(), true);
Gabor Greifba36cb52008-08-28 21:40:38 +00004489 if (SCC.getNode()) return SCC;
Evan Cheng8c7ecaf2010-01-26 02:00:44 +00004490 if (!LegalOperations ||
4491 TLI.isOperationLegal(ISD::SETCC, TLI.getSetCCResultType(VT)))
4492 return DAG.getNode(ISD::SELECT, N->getDebugLoc(), VT,
4493 DAG.getSetCC(N->getDebugLoc(),
4494 TLI.getSetCCResultType(VT),
4495 N0.getOperand(0), N0.getOperand(1),
4496 cast<CondCodeSDNode>(N0.getOperand(2))->get()),
4497 NegOne, DAG.getConstant(0, VT));
Wesley Peckbf17cfa2010-11-23 03:31:01 +00004498 }
Scott Michelfdc40a02009-02-17 22:15:04 +00004499
Dan Gohman8f0ad582008-04-28 16:58:24 +00004500 // fold (sext x) -> (zext x) if the sign bit is known zero.
Duncan Sands25cf2272008-11-24 14:53:14 +00004501 if ((!LegalOperations || TLI.isOperationLegal(ISD::ZERO_EXTEND, VT)) &&
Dan Gohman187db7b2008-04-28 18:47:17 +00004502 DAG.SignBitIsZero(N0))
Bill Wendling6ce610f2009-01-30 22:23:15 +00004503 return DAG.getNode(ISD::ZERO_EXTEND, N->getDebugLoc(), VT, N0);
Scott Michelfdc40a02009-02-17 22:15:04 +00004504
Evan Chengb3a3d5e2010-04-28 07:10:39 +00004505 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00004506}
4507
Rafael Espindoladecbc432012-04-09 16:06:03 +00004508// isTruncateOf - If N is a truncate of some other value, return true, record
4509// the value being truncated in Op and which of Op's bits are zero in KnownZero.
4510// This function computes KnownZero to avoid a duplicated call to
4511// ComputeMaskedBits in the caller.
4512static bool isTruncateOf(SelectionDAG &DAG, SDValue N, SDValue &Op,
4513 APInt &KnownZero) {
4514 APInt KnownOne;
4515 if (N->getOpcode() == ISD::TRUNCATE) {
4516 Op = N->getOperand(0);
4517 DAG.ComputeMaskedBits(Op, KnownZero, KnownOne);
4518 return true;
4519 }
4520
4521 if (N->getOpcode() != ISD::SETCC || N->getValueType(0) != MVT::i1 ||
4522 cast<CondCodeSDNode>(N->getOperand(2))->get() != ISD::SETNE)
4523 return false;
4524
4525 SDValue Op0 = N->getOperand(0);
4526 SDValue Op1 = N->getOperand(1);
4527 assert(Op0.getValueType() == Op1.getValueType());
4528
4529 ConstantSDNode *COp0 = dyn_cast<ConstantSDNode>(Op0);
4530 ConstantSDNode *COp1 = dyn_cast<ConstantSDNode>(Op1);
Rafael Espindolafdb230a2012-04-10 00:16:22 +00004531 if (COp0 && COp0->isNullValue())
Rafael Espindoladecbc432012-04-09 16:06:03 +00004532 Op = Op1;
Rafael Espindolafdb230a2012-04-10 00:16:22 +00004533 else if (COp1 && COp1->isNullValue())
Rafael Espindoladecbc432012-04-09 16:06:03 +00004534 Op = Op0;
4535 else
4536 return false;
4537
4538 DAG.ComputeMaskedBits(Op, KnownZero, KnownOne);
4539
4540 if (!(KnownZero | APInt(Op.getValueSizeInBits(), 1)).isAllOnesValue())
4541 return false;
4542
4543 return true;
4544}
4545
Dan Gohman475871a2008-07-27 21:46:04 +00004546SDValue DAGCombiner::visitZERO_EXTEND(SDNode *N) {
4547 SDValue N0 = N->getOperand(0);
Owen Andersone50ed302009-08-10 22:56:29 +00004548 EVT VT = N->getValueType(0);
Nate Begeman1d4d4142005-09-01 00:19:25 +00004549
Nate Begeman1d4d4142005-09-01 00:19:25 +00004550 // fold (zext c1) -> c1
Reid Spencer3ed469c2006-11-02 20:25:50 +00004551 if (isa<ConstantSDNode>(N0))
Bill Wendling6ce610f2009-01-30 22:23:15 +00004552 return DAG.getNode(ISD::ZERO_EXTEND, N->getDebugLoc(), VT, N0);
Nate Begeman1d4d4142005-09-01 00:19:25 +00004553 // fold (zext (zext x)) -> (zext x)
Chris Lattner310b5782006-05-06 23:06:26 +00004554 // fold (zext (aext x)) -> (zext x)
4555 if (N0.getOpcode() == ISD::ZERO_EXTEND || N0.getOpcode() == ISD::ANY_EXTEND)
Bill Wendling6ce610f2009-01-30 22:23:15 +00004556 return DAG.getNode(ISD::ZERO_EXTEND, N->getDebugLoc(), VT,
4557 N0.getOperand(0));
Chris Lattner6007b842006-09-21 06:00:20 +00004558
Chandler Carruthf103b3d2012-01-11 08:41:08 +00004559 // fold (zext (truncate x)) -> (zext x) or
4560 // (zext (truncate x)) -> (truncate x)
4561 // This is valid when the truncated bits of x are already zero.
4562 // FIXME: We should extend this to work for vectors too.
Rafael Espindoladecbc432012-04-09 16:06:03 +00004563 SDValue Op;
4564 APInt KnownZero;
4565 if (!VT.isVector() && isTruncateOf(DAG, N0, Op, KnownZero)) {
4566 APInt TruncatedBits =
4567 (Op.getValueSizeInBits() == N0.getValueSizeInBits()) ?
4568 APInt(Op.getValueSizeInBits(), 0) :
4569 APInt::getBitsSet(Op.getValueSizeInBits(),
4570 N0.getValueSizeInBits(),
4571 std::min(Op.getValueSizeInBits(),
4572 VT.getSizeInBits()));
Rafael Espindola26c8dcc2012-04-04 12:51:34 +00004573 if (TruncatedBits == (KnownZero & TruncatedBits)) {
Chandler Carruthf103b3d2012-01-11 08:41:08 +00004574 if (VT.bitsGT(Op.getValueType()))
4575 return DAG.getNode(ISD::ZERO_EXTEND, N->getDebugLoc(), VT, Op);
4576 if (VT.bitsLT(Op.getValueType()))
4577 return DAG.getNode(ISD::TRUNCATE, N->getDebugLoc(), VT, Op);
4578
4579 return Op;
4580 }
4581 }
4582
Evan Chengc88138f2007-03-22 01:54:19 +00004583 // fold (zext (truncate (load x))) -> (zext (smaller load x))
4584 // fold (zext (truncate (srl (load x), c))) -> (zext (small load (x+c/n)))
Dale Johannesen2041a0e2007-03-30 21:38:07 +00004585 if (N0.getOpcode() == ISD::TRUNCATE) {
Gabor Greifba36cb52008-08-28 21:40:38 +00004586 SDValue NarrowLoad = ReduceLoadWidth(N0.getNode());
4587 if (NarrowLoad.getNode()) {
Dale Johannesen61734eb2010-05-25 17:50:03 +00004588 SDNode* oye = N0.getNode()->getOperand(0).getNode();
4589 if (NarrowLoad.getNode() != N0.getNode()) {
Gabor Greifba36cb52008-08-28 21:40:38 +00004590 CombineTo(N0.getNode(), NarrowLoad);
Dale Johannesen61734eb2010-05-25 17:50:03 +00004591 // CombineTo deleted the truncate, if needed, but not what's under it.
4592 AddToWorkList(oye);
4593 }
Eli Friedmane545d382011-04-16 23:25:34 +00004594 return SDValue(N, 0); // Return N so it doesn't get rechecked!
Evan Cheng0b063de2007-03-23 02:16:52 +00004595 }
Evan Chengc88138f2007-03-22 01:54:19 +00004596 }
4597
Chris Lattner6007b842006-09-21 06:00:20 +00004598 // fold (zext (truncate x)) -> (and x, mask)
4599 if (N0.getOpcode() == ISD::TRUNCATE &&
Dan Gohman4e39e9d2010-06-24 14:30:44 +00004600 (!LegalOperations || TLI.isOperationLegal(ISD::AND, VT))) {
Dan Gohman394d6292010-11-03 01:47:46 +00004601
4602 // fold (zext (truncate (load x))) -> (zext (smaller load x))
4603 // fold (zext (truncate (srl (load x), c))) -> (zext (smaller load (x+c/n)))
4604 SDValue NarrowLoad = ReduceLoadWidth(N0.getNode());
4605 if (NarrowLoad.getNode()) {
4606 SDNode* oye = N0.getNode()->getOperand(0).getNode();
4607 if (NarrowLoad.getNode() != N0.getNode()) {
4608 CombineTo(N0.getNode(), NarrowLoad);
4609 // CombineTo deleted the truncate, if needed, but not what's under it.
4610 AddToWorkList(oye);
4611 }
4612 return SDValue(N, 0); // Return N so it doesn't get rechecked!
4613 }
4614
Dan Gohman475871a2008-07-27 21:46:04 +00004615 SDValue Op = N0.getOperand(0);
Duncan Sands8e4eb092008-06-08 20:54:56 +00004616 if (Op.getValueType().bitsLT(VT)) {
Bill Wendling9729c5a2009-01-31 03:12:48 +00004617 Op = DAG.getNode(ISD::ANY_EXTEND, N->getDebugLoc(), VT, Op);
Elena Demikhovsky1da58672012-04-22 09:39:03 +00004618 AddToWorkList(Op.getNode());
Duncan Sands8e4eb092008-06-08 20:54:56 +00004619 } else if (Op.getValueType().bitsGT(VT)) {
Bill Wendling9729c5a2009-01-31 03:12:48 +00004620 Op = DAG.getNode(ISD::TRUNCATE, N->getDebugLoc(), VT, Op);
Elena Demikhovsky1da58672012-04-22 09:39:03 +00004621 AddToWorkList(Op.getNode());
Chris Lattner6007b842006-09-21 06:00:20 +00004622 }
Dan Gohman87862e72009-12-11 21:31:27 +00004623 return DAG.getZeroExtendInReg(Op, N->getDebugLoc(),
4624 N0.getValueType().getScalarType());
Chris Lattner6007b842006-09-21 06:00:20 +00004625 }
Scott Michelfdc40a02009-02-17 22:15:04 +00004626
Dan Gohman97121ba2009-04-08 00:15:30 +00004627 // Fold (zext (and (trunc x), cst)) -> (and x, cst),
4628 // if either of the casts is not free.
Chris Lattner111c2282006-09-21 06:14:31 +00004629 if (N0.getOpcode() == ISD::AND &&
4630 N0.getOperand(0).getOpcode() == ISD::TRUNCATE &&
Dan Gohman97121ba2009-04-08 00:15:30 +00004631 N0.getOperand(1).getOpcode() == ISD::Constant &&
4632 (!TLI.isTruncateFree(N0.getOperand(0).getOperand(0).getValueType(),
4633 N0.getValueType()) ||
4634 !TLI.isZExtFree(N0.getValueType(), VT))) {
Dan Gohman475871a2008-07-27 21:46:04 +00004635 SDValue X = N0.getOperand(0).getOperand(0);
Duncan Sands8e4eb092008-06-08 20:54:56 +00004636 if (X.getValueType().bitsLT(VT)) {
Bill Wendling9729c5a2009-01-31 03:12:48 +00004637 X = DAG.getNode(ISD::ANY_EXTEND, X.getDebugLoc(), VT, X);
Duncan Sands8e4eb092008-06-08 20:54:56 +00004638 } else if (X.getValueType().bitsGT(VT)) {
Bill Wendling9729c5a2009-01-31 03:12:48 +00004639 X = DAG.getNode(ISD::TRUNCATE, X.getDebugLoc(), VT, X);
Chris Lattner111c2282006-09-21 06:14:31 +00004640 }
Dan Gohman220a8232008-03-03 23:51:38 +00004641 APInt Mask = cast<ConstantSDNode>(N0.getOperand(1))->getAPIntValue();
Jay Foad40f8f622010-12-07 08:25:19 +00004642 Mask = Mask.zext(VT.getSizeInBits());
Bill Wendling6ce610f2009-01-30 22:23:15 +00004643 return DAG.getNode(ISD::AND, N->getDebugLoc(), VT,
4644 X, DAG.getConstant(Mask, VT));
Chris Lattner111c2282006-09-21 06:14:31 +00004645 }
Scott Michelfdc40a02009-02-17 22:15:04 +00004646
Evan Cheng110dec22005-12-14 02:19:23 +00004647 // fold (zext (load x)) -> (zext (truncate (zextload x)))
Nadav Rotemed9b9342011-02-20 12:37:50 +00004648 // None of the supported targets knows how to perform load and vector_zext
Nadav Rotemfcd96192011-02-27 07:40:43 +00004649 // on vectors in one instruction. We only perform this transformation on
4650 // scalars.
Nadav Rotemed9b9342011-02-20 12:37:50 +00004651 if (ISD::isNON_EXTLoad(N0.getNode()) && !VT.isVector() &&
Duncan Sands25cf2272008-11-24 14:53:14 +00004652 ((!LegalOperations && !cast<LoadSDNode>(N0)->isVolatile()) ||
Evan Cheng03294662008-10-14 21:26:46 +00004653 TLI.isLoadExtLegal(ISD::ZEXTLOAD, N0.getValueType()))) {
Evan Cheng3c3ddb32007-10-29 19:58:20 +00004654 bool DoXform = true;
4655 SmallVector<SDNode*, 4> SetCCs;
4656 if (!N0.hasOneUse())
4657 DoXform = ExtendUsesToFormExtLoad(N, N0, ISD::ZERO_EXTEND, SetCCs, TLI);
4658 if (DoXform) {
4659 LoadSDNode *LN0 = cast<LoadSDNode>(N0);
Stuart Hastingsa9011292011-02-16 16:23:55 +00004660 SDValue ExtLoad = DAG.getExtLoad(ISD::ZEXTLOAD, N->getDebugLoc(), VT,
Bill Wendling6ce610f2009-01-30 22:23:15 +00004661 LN0->getChain(),
Chris Lattner3d6ccfb2010-09-21 17:04:51 +00004662 LN0->getBasePtr(), LN0->getPointerInfo(),
Duncan Sands25cf2272008-11-24 14:53:14 +00004663 N0.getValueType(),
David Greene1e559442010-02-15 17:00:31 +00004664 LN0->isVolatile(), LN0->isNonTemporal(),
4665 LN0->getAlignment());
Evan Cheng3c3ddb32007-10-29 19:58:20 +00004666 CombineTo(N, ExtLoad);
Bill Wendling6ce610f2009-01-30 22:23:15 +00004667 SDValue Trunc = DAG.getNode(ISD::TRUNCATE, N0.getDebugLoc(),
4668 N0.getValueType(), ExtLoad);
Gabor Greifba36cb52008-08-28 21:40:38 +00004669 CombineTo(N0.getNode(), Trunc, ExtLoad.getValue(1));
Bill Wendling6ce610f2009-01-30 22:23:15 +00004670
Nick Lewyckyc06b5bf2011-06-16 01:15:49 +00004671 ExtendSetCCUses(SetCCs, Trunc, ExtLoad, N->getDebugLoc(),
4672 ISD::ZERO_EXTEND);
Dan Gohman475871a2008-07-27 21:46:04 +00004673 return SDValue(N, 0); // Return N so it doesn't get rechecked!
Evan Cheng3c3ddb32007-10-29 19:58:20 +00004674 }
Evan Cheng110dec22005-12-14 02:19:23 +00004675 }
Chris Lattnerad25d4e2005-12-14 19:05:06 +00004676
Nick Lewyckyc06b5bf2011-06-16 01:15:49 +00004677 // fold (zext (and/or/xor (load x), cst)) ->
4678 // (and/or/xor (zextload x), (zext cst))
4679 if ((N0.getOpcode() == ISD::AND || N0.getOpcode() == ISD::OR ||
4680 N0.getOpcode() == ISD::XOR) &&
4681 isa<LoadSDNode>(N0.getOperand(0)) &&
4682 N0.getOperand(1).getOpcode() == ISD::Constant &&
4683 TLI.isLoadExtLegal(ISD::ZEXTLOAD, N0.getValueType()) &&
4684 (!LegalOperations && TLI.isOperationLegal(N0.getOpcode(), VT))) {
4685 LoadSDNode *LN0 = cast<LoadSDNode>(N0.getOperand(0));
4686 if (LN0->getExtensionType() != ISD::SEXTLOAD) {
4687 bool DoXform = true;
4688 SmallVector<SDNode*, 4> SetCCs;
4689 if (!N0.hasOneUse())
4690 DoXform = ExtendUsesToFormExtLoad(N, N0.getOperand(0), ISD::ZERO_EXTEND,
4691 SetCCs, TLI);
4692 if (DoXform) {
4693 SDValue ExtLoad = DAG.getExtLoad(ISD::ZEXTLOAD, LN0->getDebugLoc(), VT,
4694 LN0->getChain(), LN0->getBasePtr(),
4695 LN0->getPointerInfo(),
4696 LN0->getMemoryVT(),
4697 LN0->isVolatile(),
4698 LN0->isNonTemporal(),
4699 LN0->getAlignment());
4700 APInt Mask = cast<ConstantSDNode>(N0.getOperand(1))->getAPIntValue();
4701 Mask = Mask.zext(VT.getSizeInBits());
4702 SDValue And = DAG.getNode(N0.getOpcode(), N->getDebugLoc(), VT,
4703 ExtLoad, DAG.getConstant(Mask, VT));
4704 SDValue Trunc = DAG.getNode(ISD::TRUNCATE,
4705 N0.getOperand(0).getDebugLoc(),
4706 N0.getOperand(0).getValueType(), ExtLoad);
4707 CombineTo(N, And);
4708 CombineTo(N0.getOperand(0).getNode(), Trunc, ExtLoad.getValue(1));
4709 ExtendSetCCUses(SetCCs, Trunc, ExtLoad, N->getDebugLoc(),
4710 ISD::ZERO_EXTEND);
4711 return SDValue(N, 0); // Return N so it doesn't get rechecked!
4712 }
4713 }
4714 }
4715
Chris Lattnerad25d4e2005-12-14 19:05:06 +00004716 // fold (zext (zextload x)) -> (zext (truncate (zextload x)))
4717 // fold (zext ( extload x)) -> (zext (truncate (zextload x)))
Gabor Greifba36cb52008-08-28 21:40:38 +00004718 if ((ISD::isZEXTLoad(N0.getNode()) || ISD::isEXTLoad(N0.getNode())) &&
4719 ISD::isUNINDEXEDLoad(N0.getNode()) && N0.hasOneUse()) {
Evan Cheng466685d2006-10-09 20:57:25 +00004720 LoadSDNode *LN0 = cast<LoadSDNode>(N0);
Dan Gohman8a55ce42009-09-23 21:02:20 +00004721 EVT MemVT = LN0->getMemoryVT();
Duncan Sands25cf2272008-11-24 14:53:14 +00004722 if ((!LegalOperations && !LN0->isVolatile()) ||
Dan Gohman8a55ce42009-09-23 21:02:20 +00004723 TLI.isLoadExtLegal(ISD::ZEXTLOAD, MemVT)) {
Stuart Hastingsa9011292011-02-16 16:23:55 +00004724 SDValue ExtLoad = DAG.getExtLoad(ISD::ZEXTLOAD, N->getDebugLoc(), VT,
Bill Wendling6ce610f2009-01-30 22:23:15 +00004725 LN0->getChain(),
Chris Lattner3d6ccfb2010-09-21 17:04:51 +00004726 LN0->getBasePtr(), LN0->getPointerInfo(),
4727 MemVT,
David Greene1e559442010-02-15 17:00:31 +00004728 LN0->isVolatile(), LN0->isNonTemporal(),
4729 LN0->getAlignment());
Duncan Sandsd4b9c172008-06-13 19:07:40 +00004730 CombineTo(N, ExtLoad);
Gabor Greif12632d22008-08-30 19:29:20 +00004731 CombineTo(N0.getNode(),
Bill Wendling6ce610f2009-01-30 22:23:15 +00004732 DAG.getNode(ISD::TRUNCATE, N0.getDebugLoc(), N0.getValueType(),
4733 ExtLoad),
Duncan Sandsd4b9c172008-06-13 19:07:40 +00004734 ExtLoad.getValue(1));
Dan Gohman475871a2008-07-27 21:46:04 +00004735 return SDValue(N, 0); // Return N so it doesn't get rechecked!
Duncan Sandsd4b9c172008-06-13 19:07:40 +00004736 }
Chris Lattnerad25d4e2005-12-14 19:05:06 +00004737 }
Scott Michelfdc40a02009-02-17 22:15:04 +00004738
Chris Lattner20a35c32007-04-11 05:32:27 +00004739 if (N0.getOpcode() == ISD::SETCC) {
Evan Cheng0a942db2010-05-19 01:08:17 +00004740 if (!LegalOperations && VT.isVector()) {
4741 // zext(setcc) -> (and (vsetcc), (1, 1, ...) for vectors.
4742 // Only do this before legalize for now.
4743 EVT N0VT = N0.getOperand(0).getValueType();
4744 EVT EltVT = VT.getVectorElementType();
4745 SmallVector<SDValue,8> OneOps(VT.getVectorNumElements(),
4746 DAG.getConstant(1, EltVT));
Dan Gohman71dc7c92011-05-17 22:20:36 +00004747 if (VT.getSizeInBits() == N0VT.getSizeInBits())
Evan Cheng0a942db2010-05-19 01:08:17 +00004748 // We know that the # elements of the results is the same as the
4749 // # elements of the compare (and the # elements of the compare result
4750 // for that matter). Check to see that they are the same size. If so,
4751 // we know that the element size of the sext'd result matches the
4752 // element size of the compare operands.
4753 return DAG.getNode(ISD::AND, N->getDebugLoc(), VT,
Duncan Sands28b77e92011-09-06 19:07:46 +00004754 DAG.getSetCC(N->getDebugLoc(), VT, N0.getOperand(0),
Evan Cheng0a942db2010-05-19 01:08:17 +00004755 N0.getOperand(1),
4756 cast<CondCodeSDNode>(N0.getOperand(2))->get()),
4757 DAG.getNode(ISD::BUILD_VECTOR, N->getDebugLoc(), VT,
4758 &OneOps[0], OneOps.size()));
Dan Gohman71dc7c92011-05-17 22:20:36 +00004759
4760 // If the desired elements are smaller or larger than the source
4761 // elements we can use a matching integer vector type and then
4762 // truncate/sign extend
4763 EVT MatchingElementType =
4764 EVT::getIntegerVT(*DAG.getContext(),
4765 N0VT.getScalarType().getSizeInBits());
4766 EVT MatchingVectorType =
4767 EVT::getVectorVT(*DAG.getContext(), MatchingElementType,
4768 N0VT.getVectorNumElements());
4769 SDValue VsetCC =
Duncan Sands28b77e92011-09-06 19:07:46 +00004770 DAG.getSetCC(N->getDebugLoc(), MatchingVectorType, N0.getOperand(0),
Dan Gohman71dc7c92011-05-17 22:20:36 +00004771 N0.getOperand(1),
4772 cast<CondCodeSDNode>(N0.getOperand(2))->get());
4773 return DAG.getNode(ISD::AND, N->getDebugLoc(), VT,
4774 DAG.getSExtOrTrunc(VsetCC, N->getDebugLoc(), VT),
4775 DAG.getNode(ISD::BUILD_VECTOR, N->getDebugLoc(), VT,
4776 &OneOps[0], OneOps.size()));
Evan Cheng0a942db2010-05-19 01:08:17 +00004777 }
4778
4779 // zext(setcc x,y,cc) -> select_cc x, y, 1, 0, cc
Scott Michelfdc40a02009-02-17 22:15:04 +00004780 SDValue SCC =
Bill Wendling836ca7d2009-01-30 23:59:18 +00004781 SimplifySelectCC(N->getDebugLoc(), N0.getOperand(0), N0.getOperand(1),
Chris Lattner20a35c32007-04-11 05:32:27 +00004782 DAG.getConstant(1, VT), DAG.getConstant(0, VT),
Chris Lattner1eba01e2007-04-11 06:50:51 +00004783 cast<CondCodeSDNode>(N0.getOperand(2))->get(), true);
Gabor Greifba36cb52008-08-28 21:40:38 +00004784 if (SCC.getNode()) return SCC;
Chris Lattner20a35c32007-04-11 05:32:27 +00004785 }
Scott Michelfdc40a02009-02-17 22:15:04 +00004786
Evan Cheng9818c042009-12-15 03:00:32 +00004787 // (zext (shl (zext x), cst)) -> (shl (zext x), cst)
Evan Cheng99b653c2009-12-15 00:41:36 +00004788 if ((N0.getOpcode() == ISD::SHL || N0.getOpcode() == ISD::SRL) &&
Evan Cheng9818c042009-12-15 03:00:32 +00004789 isa<ConstantSDNode>(N0.getOperand(1)) &&
Evan Cheng99b653c2009-12-15 00:41:36 +00004790 N0.getOperand(0).getOpcode() == ISD::ZERO_EXTEND &&
4791 N0.hasOneUse()) {
Chris Lattnere0751182011-02-13 19:09:16 +00004792 SDValue ShAmt = N0.getOperand(1);
4793 unsigned ShAmtVal = cast<ConstantSDNode>(ShAmt)->getZExtValue();
Evan Cheng9818c042009-12-15 03:00:32 +00004794 if (N0.getOpcode() == ISD::SHL) {
Chris Lattnere0751182011-02-13 19:09:16 +00004795 SDValue InnerZExt = N0.getOperand(0);
Evan Cheng9818c042009-12-15 03:00:32 +00004796 // If the original shl may be shifting out bits, do not perform this
4797 // transformation.
Chris Lattnere0751182011-02-13 19:09:16 +00004798 unsigned KnownZeroBits = InnerZExt.getValueType().getSizeInBits() -
4799 InnerZExt.getOperand(0).getValueType().getSizeInBits();
4800 if (ShAmtVal > KnownZeroBits)
Evan Cheng9818c042009-12-15 03:00:32 +00004801 return SDValue();
4802 }
Chris Lattnere0751182011-02-13 19:09:16 +00004803
4804 DebugLoc DL = N->getDebugLoc();
Owen Anderson95771af2011-02-25 21:41:48 +00004805
4806 // Ensure that the shift amount is wide enough for the shifted value.
Chris Lattnere0751182011-02-13 19:09:16 +00004807 if (VT.getSizeInBits() >= 256)
4808 ShAmt = DAG.getNode(ISD::ZERO_EXTEND, DL, MVT::i32, ShAmt);
Owen Anderson95771af2011-02-25 21:41:48 +00004809
Chris Lattnere0751182011-02-13 19:09:16 +00004810 return DAG.getNode(N0.getOpcode(), DL, VT,
4811 DAG.getNode(ISD::ZERO_EXTEND, DL, VT, N0.getOperand(0)),
4812 ShAmt);
Evan Cheng99b653c2009-12-15 00:41:36 +00004813 }
4814
Evan Chengb3a3d5e2010-04-28 07:10:39 +00004815 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00004816}
4817
Dan Gohman475871a2008-07-27 21:46:04 +00004818SDValue DAGCombiner::visitANY_EXTEND(SDNode *N) {
4819 SDValue N0 = N->getOperand(0);
Owen Andersone50ed302009-08-10 22:56:29 +00004820 EVT VT = N->getValueType(0);
Scott Michelfdc40a02009-02-17 22:15:04 +00004821
Chris Lattner5ffc0662006-05-05 05:58:59 +00004822 // fold (aext c1) -> c1
Chris Lattner310b5782006-05-06 23:06:26 +00004823 if (isa<ConstantSDNode>(N0))
Bill Wendlingfc4b6772009-02-01 11:19:36 +00004824 return DAG.getNode(ISD::ANY_EXTEND, N->getDebugLoc(), VT, N0);
Chris Lattner5ffc0662006-05-05 05:58:59 +00004825 // fold (aext (aext x)) -> (aext x)
4826 // fold (aext (zext x)) -> (zext x)
4827 // fold (aext (sext x)) -> (sext x)
4828 if (N0.getOpcode() == ISD::ANY_EXTEND ||
4829 N0.getOpcode() == ISD::ZERO_EXTEND ||
4830 N0.getOpcode() == ISD::SIGN_EXTEND)
Bill Wendling683c9572009-01-30 22:27:33 +00004831 return DAG.getNode(N0.getOpcode(), N->getDebugLoc(), VT, N0.getOperand(0));
Scott Michelfdc40a02009-02-17 22:15:04 +00004832
Evan Chengc88138f2007-03-22 01:54:19 +00004833 // fold (aext (truncate (load x))) -> (aext (smaller load x))
4834 // fold (aext (truncate (srl (load x), c))) -> (aext (small load (x+c/n)))
4835 if (N0.getOpcode() == ISD::TRUNCATE) {
Gabor Greifba36cb52008-08-28 21:40:38 +00004836 SDValue NarrowLoad = ReduceLoadWidth(N0.getNode());
4837 if (NarrowLoad.getNode()) {
Dale Johannesen86234c32010-05-25 18:47:23 +00004838 SDNode* oye = N0.getNode()->getOperand(0).getNode();
4839 if (NarrowLoad.getNode() != N0.getNode()) {
Gabor Greifba36cb52008-08-28 21:40:38 +00004840 CombineTo(N0.getNode(), NarrowLoad);
Dale Johannesen86234c32010-05-25 18:47:23 +00004841 // CombineTo deleted the truncate, if needed, but not what's under it.
4842 AddToWorkList(oye);
4843 }
Eli Friedmane545d382011-04-16 23:25:34 +00004844 return SDValue(N, 0); // Return N so it doesn't get rechecked!
Evan Cheng0b063de2007-03-23 02:16:52 +00004845 }
Evan Chengc88138f2007-03-22 01:54:19 +00004846 }
4847
Chris Lattner84750582006-09-20 06:29:17 +00004848 // fold (aext (truncate x))
4849 if (N0.getOpcode() == ISD::TRUNCATE) {
Dan Gohman475871a2008-07-27 21:46:04 +00004850 SDValue TruncOp = N0.getOperand(0);
Chris Lattner84750582006-09-20 06:29:17 +00004851 if (TruncOp.getValueType() == VT)
Sylvestre Ledru94c22712012-09-27 10:14:43 +00004852 return TruncOp; // x iff x size == zext size.
Duncan Sands8e4eb092008-06-08 20:54:56 +00004853 if (TruncOp.getValueType().bitsGT(VT))
Bill Wendling683c9572009-01-30 22:27:33 +00004854 return DAG.getNode(ISD::TRUNCATE, N->getDebugLoc(), VT, TruncOp);
4855 return DAG.getNode(ISD::ANY_EXTEND, N->getDebugLoc(), VT, TruncOp);
Chris Lattner84750582006-09-20 06:29:17 +00004856 }
Scott Michelfdc40a02009-02-17 22:15:04 +00004857
Dan Gohman97121ba2009-04-08 00:15:30 +00004858 // Fold (aext (and (trunc x), cst)) -> (and x, cst)
4859 // if the trunc is not free.
Chris Lattner0e4b9222006-09-21 06:40:43 +00004860 if (N0.getOpcode() == ISD::AND &&
4861 N0.getOperand(0).getOpcode() == ISD::TRUNCATE &&
Dan Gohman97121ba2009-04-08 00:15:30 +00004862 N0.getOperand(1).getOpcode() == ISD::Constant &&
4863 !TLI.isTruncateFree(N0.getOperand(0).getOperand(0).getValueType(),
4864 N0.getValueType())) {
Dan Gohman475871a2008-07-27 21:46:04 +00004865 SDValue X = N0.getOperand(0).getOperand(0);
Duncan Sands8e4eb092008-06-08 20:54:56 +00004866 if (X.getValueType().bitsLT(VT)) {
Bill Wendling9729c5a2009-01-31 03:12:48 +00004867 X = DAG.getNode(ISD::ANY_EXTEND, N->getDebugLoc(), VT, X);
Duncan Sands8e4eb092008-06-08 20:54:56 +00004868 } else if (X.getValueType().bitsGT(VT)) {
Bill Wendling9729c5a2009-01-31 03:12:48 +00004869 X = DAG.getNode(ISD::TRUNCATE, N->getDebugLoc(), VT, X);
Chris Lattner0e4b9222006-09-21 06:40:43 +00004870 }
Dan Gohman220a8232008-03-03 23:51:38 +00004871 APInt Mask = cast<ConstantSDNode>(N0.getOperand(1))->getAPIntValue();
Jay Foad40f8f622010-12-07 08:25:19 +00004872 Mask = Mask.zext(VT.getSizeInBits());
Bill Wendling683c9572009-01-30 22:27:33 +00004873 return DAG.getNode(ISD::AND, N->getDebugLoc(), VT,
4874 X, DAG.getConstant(Mask, VT));
Chris Lattner0e4b9222006-09-21 06:40:43 +00004875 }
Scott Michelfdc40a02009-02-17 22:15:04 +00004876
Chris Lattner5ffc0662006-05-05 05:58:59 +00004877 // fold (aext (load x)) -> (aext (truncate (extload x)))
Nadav Rotem8c20ec52011-02-24 21:01:34 +00004878 // None of the supported targets knows how to perform load and any_ext
Nadav Rotemfcd96192011-02-27 07:40:43 +00004879 // on vectors in one instruction. We only perform this transformation on
4880 // scalars.
Nadav Rotem8c20ec52011-02-24 21:01:34 +00004881 if (ISD::isNON_EXTLoad(N0.getNode()) && !VT.isVector() &&
Duncan Sands25cf2272008-11-24 14:53:14 +00004882 ((!LegalOperations && !cast<LoadSDNode>(N0)->isVolatile()) ||
Evan Cheng03294662008-10-14 21:26:46 +00004883 TLI.isLoadExtLegal(ISD::EXTLOAD, N0.getValueType()))) {
Dan Gohman57fc82d2009-04-09 03:51:29 +00004884 bool DoXform = true;
4885 SmallVector<SDNode*, 4> SetCCs;
4886 if (!N0.hasOneUse())
4887 DoXform = ExtendUsesToFormExtLoad(N, N0, ISD::ANY_EXTEND, SetCCs, TLI);
4888 if (DoXform) {
4889 LoadSDNode *LN0 = cast<LoadSDNode>(N0);
Stuart Hastingsa9011292011-02-16 16:23:55 +00004890 SDValue ExtLoad = DAG.getExtLoad(ISD::EXTLOAD, N->getDebugLoc(), VT,
Dan Gohman57fc82d2009-04-09 03:51:29 +00004891 LN0->getChain(),
Chris Lattner3d6ccfb2010-09-21 17:04:51 +00004892 LN0->getBasePtr(), LN0->getPointerInfo(),
Dan Gohman57fc82d2009-04-09 03:51:29 +00004893 N0.getValueType(),
David Greene1e559442010-02-15 17:00:31 +00004894 LN0->isVolatile(), LN0->isNonTemporal(),
4895 LN0->getAlignment());
Dan Gohman57fc82d2009-04-09 03:51:29 +00004896 CombineTo(N, ExtLoad);
4897 SDValue Trunc = DAG.getNode(ISD::TRUNCATE, N0.getDebugLoc(),
4898 N0.getValueType(), ExtLoad);
4899 CombineTo(N0.getNode(), Trunc, ExtLoad.getValue(1));
Nick Lewyckyc06b5bf2011-06-16 01:15:49 +00004900 ExtendSetCCUses(SetCCs, Trunc, ExtLoad, N->getDebugLoc(),
4901 ISD::ANY_EXTEND);
Dan Gohman57fc82d2009-04-09 03:51:29 +00004902 return SDValue(N, 0); // Return N so it doesn't get rechecked!
4903 }
Chris Lattner5ffc0662006-05-05 05:58:59 +00004904 }
Scott Michelfdc40a02009-02-17 22:15:04 +00004905
Chris Lattner5ffc0662006-05-05 05:58:59 +00004906 // fold (aext (zextload x)) -> (aext (truncate (zextload x)))
4907 // fold (aext (sextload x)) -> (aext (truncate (sextload x)))
4908 // fold (aext ( extload x)) -> (aext (truncate (extload x)))
Evan Cheng83060c52007-03-07 08:07:03 +00004909 if (N0.getOpcode() == ISD::LOAD &&
Gabor Greifba36cb52008-08-28 21:40:38 +00004910 !ISD::isNON_EXTLoad(N0.getNode()) && ISD::isUNINDEXEDLoad(N0.getNode()) &&
Evan Cheng466685d2006-10-09 20:57:25 +00004911 N0.hasOneUse()) {
4912 LoadSDNode *LN0 = cast<LoadSDNode>(N0);
Dan Gohman8a55ce42009-09-23 21:02:20 +00004913 EVT MemVT = LN0->getMemoryVT();
Stuart Hastingsa9011292011-02-16 16:23:55 +00004914 SDValue ExtLoad = DAG.getExtLoad(LN0->getExtensionType(), N->getDebugLoc(),
4915 VT, LN0->getChain(), LN0->getBasePtr(),
Chris Lattner3d6ccfb2010-09-21 17:04:51 +00004916 LN0->getPointerInfo(), MemVT,
David Greene1e559442010-02-15 17:00:31 +00004917 LN0->isVolatile(), LN0->isNonTemporal(),
4918 LN0->getAlignment());
Chris Lattner5ffc0662006-05-05 05:58:59 +00004919 CombineTo(N, ExtLoad);
Evan Cheng45299662008-08-29 23:20:46 +00004920 CombineTo(N0.getNode(),
Bill Wendling683c9572009-01-30 22:27:33 +00004921 DAG.getNode(ISD::TRUNCATE, N0.getDebugLoc(),
4922 N0.getValueType(), ExtLoad),
Chris Lattner5ffc0662006-05-05 05:58:59 +00004923 ExtLoad.getValue(1));
Dan Gohman475871a2008-07-27 21:46:04 +00004924 return SDValue(N, 0); // Return N so it doesn't get rechecked!
Chris Lattner5ffc0662006-05-05 05:58:59 +00004925 }
Scott Michelfdc40a02009-02-17 22:15:04 +00004926
Chris Lattner20a35c32007-04-11 05:32:27 +00004927 if (N0.getOpcode() == ISD::SETCC) {
Evan Cheng0a942db2010-05-19 01:08:17 +00004928 // aext(setcc) -> sext_in_reg(vsetcc) for vectors.
4929 // Only do this before legalize for now.
4930 if (VT.isVector() && !LegalOperations) {
4931 EVT N0VT = N0.getOperand(0).getValueType();
4932 // We know that the # elements of the results is the same as the
4933 // # elements of the compare (and the # elements of the compare result
4934 // for that matter). Check to see that they are the same size. If so,
4935 // we know that the element size of the sext'd result matches the
4936 // element size of the compare operands.
4937 if (VT.getSizeInBits() == N0VT.getSizeInBits())
Duncan Sands28b77e92011-09-06 19:07:46 +00004938 return DAG.getSetCC(N->getDebugLoc(), VT, N0.getOperand(0),
Duncan Sands34727662010-07-12 08:16:59 +00004939 N0.getOperand(1),
4940 cast<CondCodeSDNode>(N0.getOperand(2))->get());
Evan Cheng0a942db2010-05-19 01:08:17 +00004941 // If the desired elements are smaller or larger than the source
4942 // elements we can use a matching integer vector type and then
4943 // truncate/sign extend
4944 else {
Duncan Sands34727662010-07-12 08:16:59 +00004945 EVT MatchingElementType =
4946 EVT::getIntegerVT(*DAG.getContext(),
4947 N0VT.getScalarType().getSizeInBits());
4948 EVT MatchingVectorType =
4949 EVT::getVectorVT(*DAG.getContext(), MatchingElementType,
4950 N0VT.getVectorNumElements());
4951 SDValue VsetCC =
Duncan Sands28b77e92011-09-06 19:07:46 +00004952 DAG.getSetCC(N->getDebugLoc(), MatchingVectorType, N0.getOperand(0),
Duncan Sands34727662010-07-12 08:16:59 +00004953 N0.getOperand(1),
4954 cast<CondCodeSDNode>(N0.getOperand(2))->get());
4955 return DAG.getSExtOrTrunc(VsetCC, N->getDebugLoc(), VT);
Evan Cheng0a942db2010-05-19 01:08:17 +00004956 }
4957 }
4958
4959 // aext(setcc x,y,cc) -> select_cc x, y, 1, 0, cc
Scott Michelfdc40a02009-02-17 22:15:04 +00004960 SDValue SCC =
Bill Wendling836ca7d2009-01-30 23:59:18 +00004961 SimplifySelectCC(N->getDebugLoc(), N0.getOperand(0), N0.getOperand(1),
Chris Lattner1eba01e2007-04-11 06:50:51 +00004962 DAG.getConstant(1, VT), DAG.getConstant(0, VT),
Chris Lattnerc24bbad2007-04-11 16:51:53 +00004963 cast<CondCodeSDNode>(N0.getOperand(2))->get(), true);
Gabor Greifba36cb52008-08-28 21:40:38 +00004964 if (SCC.getNode())
Chris Lattnerc56a81d2007-04-11 06:43:25 +00004965 return SCC;
Chris Lattner20a35c32007-04-11 05:32:27 +00004966 }
Scott Michelfdc40a02009-02-17 22:15:04 +00004967
Evan Chengb3a3d5e2010-04-28 07:10:39 +00004968 return SDValue();
Chris Lattner5ffc0662006-05-05 05:58:59 +00004969}
4970
Chris Lattner2b4c2792007-10-13 06:35:54 +00004971/// GetDemandedBits - See if the specified operand can be simplified with the
4972/// knowledge that only the bits specified by Mask are used. If so, return the
Dan Gohman475871a2008-07-27 21:46:04 +00004973/// simpler operand, otherwise return a null SDValue.
4974SDValue DAGCombiner::GetDemandedBits(SDValue V, const APInt &Mask) {
Chris Lattner2b4c2792007-10-13 06:35:54 +00004975 switch (V.getOpcode()) {
4976 default: break;
Lang Hames5207bf22011-11-08 18:56:23 +00004977 case ISD::Constant: {
4978 const ConstantSDNode *CV = cast<ConstantSDNode>(V.getNode());
4979 assert(CV != 0 && "Const value should be ConstSDNode.");
4980 const APInt &CVal = CV->getAPIntValue();
4981 APInt NewVal = CVal & Mask;
4982 if (NewVal != CVal) {
4983 return DAG.getConstant(NewVal, V.getValueType());
4984 }
4985 break;
4986 }
Chris Lattner2b4c2792007-10-13 06:35:54 +00004987 case ISD::OR:
4988 case ISD::XOR:
4989 // If the LHS or RHS don't contribute bits to the or, drop them.
4990 if (DAG.MaskedValueIsZero(V.getOperand(0), Mask))
4991 return V.getOperand(1);
4992 if (DAG.MaskedValueIsZero(V.getOperand(1), Mask))
4993 return V.getOperand(0);
4994 break;
Chris Lattnere33544c2007-10-13 06:58:48 +00004995 case ISD::SRL:
4996 // Only look at single-use SRLs.
Gabor Greifba36cb52008-08-28 21:40:38 +00004997 if (!V.getNode()->hasOneUse())
Chris Lattnere33544c2007-10-13 06:58:48 +00004998 break;
4999 if (ConstantSDNode *RHSC = dyn_cast<ConstantSDNode>(V.getOperand(1))) {
5000 // See if we can recursively simplify the LHS.
Dan Gohmanf5aeb1a2008-09-12 16:56:44 +00005001 unsigned Amt = RHSC->getZExtValue();
Bill Wendling8509c902009-01-30 22:33:24 +00005002
Dan Gohmancc91d632009-01-03 19:22:06 +00005003 // Watch out for shift count overflow though.
5004 if (Amt >= Mask.getBitWidth()) break;
Dan Gohman2e68b6f2008-02-25 21:11:39 +00005005 APInt NewMask = Mask << Amt;
Dan Gohman475871a2008-07-27 21:46:04 +00005006 SDValue SimplifyLHS = GetDemandedBits(V.getOperand(0), NewMask);
Bill Wendling8509c902009-01-30 22:33:24 +00005007 if (SimplifyLHS.getNode())
Scott Michelfdc40a02009-02-17 22:15:04 +00005008 return DAG.getNode(ISD::SRL, V.getDebugLoc(), V.getValueType(),
Chris Lattnere33544c2007-10-13 06:58:48 +00005009 SimplifyLHS, V.getOperand(1));
Chris Lattnere33544c2007-10-13 06:58:48 +00005010 }
Chris Lattner2b4c2792007-10-13 06:35:54 +00005011 }
Dan Gohman475871a2008-07-27 21:46:04 +00005012 return SDValue();
Chris Lattner2b4c2792007-10-13 06:35:54 +00005013}
5014
Evan Chengc88138f2007-03-22 01:54:19 +00005015/// ReduceLoadWidth - If the result of a wider load is shifted to right of N
5016/// bits and then truncated to a narrower type and where N is a multiple
5017/// of number of bits of the narrower type, transform it to a narrower load
5018/// from address + N / num of bits of new type. If the result is to be
5019/// extended, also fold the extension to form a extending load.
Dan Gohman475871a2008-07-27 21:46:04 +00005020SDValue DAGCombiner::ReduceLoadWidth(SDNode *N) {
Evan Chengc88138f2007-03-22 01:54:19 +00005021 unsigned Opc = N->getOpcode();
Dan Gohman4e39e9d2010-06-24 14:30:44 +00005022
Evan Chengc88138f2007-03-22 01:54:19 +00005023 ISD::LoadExtType ExtType = ISD::NON_EXTLOAD;
Dan Gohman475871a2008-07-27 21:46:04 +00005024 SDValue N0 = N->getOperand(0);
Owen Andersone50ed302009-08-10 22:56:29 +00005025 EVT VT = N->getValueType(0);
5026 EVT ExtVT = VT;
Evan Chengc88138f2007-03-22 01:54:19 +00005027
Dan Gohman7f8613e2008-08-14 20:04:46 +00005028 // This transformation isn't valid for vector loads.
5029 if (VT.isVector())
5030 return SDValue();
5031
Dan Gohmand1996362010-01-09 02:13:55 +00005032 // Special case: SIGN_EXTEND_INREG is basically truncating to ExtVT then
Evan Chenge177e302007-03-23 22:13:36 +00005033 // extended to VT.
Evan Chengc88138f2007-03-22 01:54:19 +00005034 if (Opc == ISD::SIGN_EXTEND_INREG) {
5035 ExtType = ISD::SEXTLOAD;
Owen Andersone50ed302009-08-10 22:56:29 +00005036 ExtVT = cast<VTSDNode>(N->getOperand(1))->getVT();
Dan Gohman4e39e9d2010-06-24 14:30:44 +00005037 } else if (Opc == ISD::SRL) {
Chris Lattner90b03642010-12-21 18:05:22 +00005038 // Another special-case: SRL is basically zero-extending a narrower value.
Dan Gohman4e39e9d2010-06-24 14:30:44 +00005039 ExtType = ISD::ZEXTLOAD;
5040 N0 = SDValue(N, 0);
5041 ConstantSDNode *N01 = dyn_cast<ConstantSDNode>(N0.getOperand(1));
5042 if (!N01) return SDValue();
5043 ExtVT = EVT::getIntegerVT(*DAG.getContext(),
5044 VT.getSizeInBits() - N01->getZExtValue());
Evan Chengc88138f2007-03-22 01:54:19 +00005045 }
Richard Osborne4e3740e2011-01-31 17:41:44 +00005046 if (LegalOperations && !TLI.isLoadExtLegal(ExtType, ExtVT))
5047 return SDValue();
Evan Chengc88138f2007-03-22 01:54:19 +00005048
Owen Andersone50ed302009-08-10 22:56:29 +00005049 unsigned EVTBits = ExtVT.getSizeInBits();
Owen Anderson95771af2011-02-25 21:41:48 +00005050
Chris Lattner7a2a7fa2010-12-22 08:01:44 +00005051 // Do not generate loads of non-round integer types since these can
5052 // be expensive (and would be wrong if the type is not byte sized).
5053 if (!ExtVT.isRound())
5054 return SDValue();
Owen Anderson95771af2011-02-25 21:41:48 +00005055
Evan Chengc88138f2007-03-22 01:54:19 +00005056 unsigned ShAmt = 0;
Chris Lattner7a2a7fa2010-12-22 08:01:44 +00005057 if (N0.getOpcode() == ISD::SRL && N0.hasOneUse()) {
Evan Chengc88138f2007-03-22 01:54:19 +00005058 if (ConstantSDNode *N01 = dyn_cast<ConstantSDNode>(N0.getOperand(1))) {
Dan Gohmanf5aeb1a2008-09-12 16:56:44 +00005059 ShAmt = N01->getZExtValue();
Evan Chengc88138f2007-03-22 01:54:19 +00005060 // Is the shift amount a multiple of size of VT?
5061 if ((ShAmt & (EVTBits-1)) == 0) {
5062 N0 = N0.getOperand(0);
Eli Friedmand68eea22009-08-19 08:46:10 +00005063 // Is the load width a multiple of size of VT?
5064 if ((N0.getValueType().getSizeInBits() & (EVTBits-1)) != 0)
Dan Gohman475871a2008-07-27 21:46:04 +00005065 return SDValue();
Evan Chengc88138f2007-03-22 01:54:19 +00005066 }
Wesley Peckbf17cfa2010-11-23 03:31:01 +00005067
Chris Lattnercbf68df2010-12-22 08:02:57 +00005068 // At this point, we must have a load or else we can't do the transform.
5069 if (!isa<LoadSDNode>(N0)) return SDValue();
Owen Anderson95771af2011-02-25 21:41:48 +00005070
Chandler Carruth1c49fda2012-12-11 00:36:57 +00005071 // Because a SRL must be assumed to *need* to zero-extend the high bits
5072 // (as opposed to anyext the high bits), we can't combine the zextload
5073 // lowering of SRL and an sextload.
5074 if (cast<LoadSDNode>(N0)->getExtensionType() == ISD::SEXTLOAD)
5075 return SDValue();
5076
Chris Lattner2831a192010-10-01 05:36:09 +00005077 // If the shift amount is larger than the input type then we're not
5078 // accessing any of the loaded bytes. If the load was a zextload/extload
5079 // then the result of the shift+trunc is zero/undef (handled elsewhere).
Chris Lattnercbf68df2010-12-22 08:02:57 +00005080 if (ShAmt >= cast<LoadSDNode>(N0)->getMemoryVT().getSizeInBits())
Chris Lattner2831a192010-10-01 05:36:09 +00005081 return SDValue();
Evan Chengc88138f2007-03-22 01:54:19 +00005082 }
5083 }
5084
Dan Gohman394d6292010-11-03 01:47:46 +00005085 // If the load is shifted left (and the result isn't shifted back right),
5086 // we can fold the truncate through the shift.
5087 unsigned ShLeftAmt = 0;
5088 if (ShAmt == 0 && N0.getOpcode() == ISD::SHL && N0.hasOneUse() &&
Chris Lattner4c32bc22010-12-22 07:36:50 +00005089 ExtVT == VT && TLI.isNarrowingProfitable(N0.getValueType(), VT)) {
Dan Gohman394d6292010-11-03 01:47:46 +00005090 if (ConstantSDNode *N01 = dyn_cast<ConstantSDNode>(N0.getOperand(1))) {
5091 ShLeftAmt = N01->getZExtValue();
5092 N0 = N0.getOperand(0);
5093 }
5094 }
Owen Anderson95771af2011-02-25 21:41:48 +00005095
Chris Lattner4c32bc22010-12-22 07:36:50 +00005096 // If we haven't found a load, we can't narrow it. Don't transform one with
5097 // multiple uses, this would require adding a new load.
5098 if (!isa<LoadSDNode>(N0) || !N0.hasOneUse() ||
5099 // Don't change the width of a volatile load.
5100 cast<LoadSDNode>(N0)->isVolatile())
5101 return SDValue();
Owen Anderson95771af2011-02-25 21:41:48 +00005102
Chris Lattner7a2a7fa2010-12-22 08:01:44 +00005103 // Verify that we are actually reducing a load width here.
5104 if (cast<LoadSDNode>(N0)->getMemoryVT().getSizeInBits() < EVTBits)
Chris Lattner4c32bc22010-12-22 07:36:50 +00005105 return SDValue();
Owen Anderson95771af2011-02-25 21:41:48 +00005106
Chris Lattner4c32bc22010-12-22 07:36:50 +00005107 LoadSDNode *LN0 = cast<LoadSDNode>(N0);
5108 EVT PtrType = N0.getOperand(1).getValueType();
Bill Wendling8509c902009-01-30 22:33:24 +00005109
Evan Cheng16436df2012-06-26 01:19:33 +00005110 if (PtrType == MVT::Untyped || PtrType.isExtended())
5111 // It's not possible to generate a constant of extended or untyped type.
5112 return SDValue();
5113
Chris Lattner4c32bc22010-12-22 07:36:50 +00005114 // For big endian targets, we need to adjust the offset to the pointer to
5115 // load the correct bytes.
5116 if (TLI.isBigEndian()) {
5117 unsigned LVTStoreBits = LN0->getMemoryVT().getStoreSizeInBits();
5118 unsigned EVTStoreBits = ExtVT.getStoreSizeInBits();
5119 ShAmt = LVTStoreBits - EVTStoreBits - ShAmt;
Evan Chengc88138f2007-03-22 01:54:19 +00005120 }
5121
Chris Lattner4c32bc22010-12-22 07:36:50 +00005122 uint64_t PtrOff = ShAmt / 8;
5123 unsigned NewAlign = MinAlign(LN0->getAlignment(), PtrOff);
5124 SDValue NewPtr = DAG.getNode(ISD::ADD, LN0->getDebugLoc(),
5125 PtrType, LN0->getBasePtr(),
5126 DAG.getConstant(PtrOff, PtrType));
5127 AddToWorkList(NewPtr.getNode());
5128
Chris Lattner7a2a7fa2010-12-22 08:01:44 +00005129 SDValue Load;
5130 if (ExtType == ISD::NON_EXTLOAD)
5131 Load = DAG.getLoad(VT, N0.getDebugLoc(), LN0->getChain(), NewPtr,
5132 LN0->getPointerInfo().getWithOffset(PtrOff),
Pete Cooperd752e0f2011-11-08 18:42:53 +00005133 LN0->isVolatile(), LN0->isNonTemporal(),
5134 LN0->isInvariant(), NewAlign);
Chris Lattner7a2a7fa2010-12-22 08:01:44 +00005135 else
Stuart Hastingsa9011292011-02-16 16:23:55 +00005136 Load = DAG.getExtLoad(ExtType, N0.getDebugLoc(), VT, LN0->getChain(),NewPtr,
Chris Lattner7a2a7fa2010-12-22 08:01:44 +00005137 LN0->getPointerInfo().getWithOffset(PtrOff),
5138 ExtVT, LN0->isVolatile(), LN0->isNonTemporal(),
5139 NewAlign);
Chris Lattner4c32bc22010-12-22 07:36:50 +00005140
5141 // Replace the old load's chain with the new load's chain.
5142 WorkListRemover DeadNodes(*this);
Jakob Stoklund Olesenbc7d4482012-04-20 22:08:46 +00005143 DAG.ReplaceAllUsesOfValueWith(N0.getValue(1), Load.getValue(1));
Chris Lattner4c32bc22010-12-22 07:36:50 +00005144
5145 // Shift the result left, if we've swallowed a left shift.
5146 SDValue Result = Load;
5147 if (ShLeftAmt != 0) {
Owen Anderson95771af2011-02-25 21:41:48 +00005148 EVT ShImmTy = getShiftAmountTy(Result.getValueType());
Chris Lattner4c32bc22010-12-22 07:36:50 +00005149 if (!isUIntN(ShImmTy.getSizeInBits(), ShLeftAmt))
5150 ShImmTy = VT;
5151 Result = DAG.getNode(ISD::SHL, N0.getDebugLoc(), VT,
5152 Result, DAG.getConstant(ShLeftAmt, ShImmTy));
5153 }
5154
5155 // Return the new loaded value.
5156 return Result;
Evan Chengc88138f2007-03-22 01:54:19 +00005157}
5158
Dan Gohman475871a2008-07-27 21:46:04 +00005159SDValue DAGCombiner::visitSIGN_EXTEND_INREG(SDNode *N) {
5160 SDValue N0 = N->getOperand(0);
5161 SDValue N1 = N->getOperand(1);
Owen Andersone50ed302009-08-10 22:56:29 +00005162 EVT VT = N->getValueType(0);
5163 EVT EVT = cast<VTSDNode>(N1)->getVT();
Dan Gohman87862e72009-12-11 21:31:27 +00005164 unsigned VTBits = VT.getScalarType().getSizeInBits();
Dan Gohmand1996362010-01-09 02:13:55 +00005165 unsigned EVTBits = EVT.getScalarType().getSizeInBits();
Scott Michelfdc40a02009-02-17 22:15:04 +00005166
Nate Begeman1d4d4142005-09-01 00:19:25 +00005167 // fold (sext_in_reg c1) -> c1
Chris Lattnereaeda562006-05-08 20:59:41 +00005168 if (isa<ConstantSDNode>(N0) || N0.getOpcode() == ISD::UNDEF)
Bill Wendling8509c902009-01-30 22:33:24 +00005169 return DAG.getNode(ISD::SIGN_EXTEND_INREG, N->getDebugLoc(), VT, N0, N1);
Scott Michelfdc40a02009-02-17 22:15:04 +00005170
Chris Lattner541a24f2006-05-06 22:43:44 +00005171 // If the input is already sign extended, just drop the extension.
Dan Gohman87862e72009-12-11 21:31:27 +00005172 if (DAG.ComputeNumSignBits(N0) >= VTBits-EVTBits+1)
Chris Lattneree4ea922006-05-06 09:30:03 +00005173 return N0;
Scott Michelfdc40a02009-02-17 22:15:04 +00005174
Nate Begeman646d7e22005-09-02 21:18:40 +00005175 // fold (sext_in_reg (sext_in_reg x, VT2), VT1) -> (sext_in_reg x, minVT) pt2
5176 if (N0.getOpcode() == ISD::SIGN_EXTEND_INREG &&
Duncan Sands8e4eb092008-06-08 20:54:56 +00005177 EVT.bitsLT(cast<VTSDNode>(N0.getOperand(1))->getVT())) {
Bill Wendling8509c902009-01-30 22:33:24 +00005178 return DAG.getNode(ISD::SIGN_EXTEND_INREG, N->getDebugLoc(), VT,
5179 N0.getOperand(0), N1);
Nate Begeman646d7e22005-09-02 21:18:40 +00005180 }
Chris Lattner4b37e872006-05-08 21:18:59 +00005181
Dan Gohman75dcf082008-07-31 00:50:31 +00005182 // fold (sext_in_reg (sext x)) -> (sext x)
5183 // fold (sext_in_reg (aext x)) -> (sext x)
5184 // if x is small enough.
5185 if (N0.getOpcode() == ISD::SIGN_EXTEND || N0.getOpcode() == ISD::ANY_EXTEND) {
5186 SDValue N00 = N0.getOperand(0);
Evan Cheng003d7c42010-04-16 22:26:19 +00005187 if (N00.getValueType().getScalarType().getSizeInBits() <= EVTBits &&
5188 (!LegalOperations || TLI.isOperationLegal(ISD::SIGN_EXTEND, VT)))
Bill Wendling8509c902009-01-30 22:33:24 +00005189 return DAG.getNode(ISD::SIGN_EXTEND, N->getDebugLoc(), VT, N00, N1);
Dan Gohman75dcf082008-07-31 00:50:31 +00005190 }
5191
Chris Lattner95a5e052007-04-17 19:03:21 +00005192 // fold (sext_in_reg x) -> (zext_in_reg x) if the sign bit is known zero.
Dan Gohman2e68b6f2008-02-25 21:11:39 +00005193 if (DAG.MaskedValueIsZero(N0, APInt::getBitsSet(VTBits, EVTBits-1, EVTBits)))
Bill Wendlingfc4b6772009-02-01 11:19:36 +00005194 return DAG.getZeroExtendInReg(N0, N->getDebugLoc(), EVT);
Scott Michelfdc40a02009-02-17 22:15:04 +00005195
Chris Lattner95a5e052007-04-17 19:03:21 +00005196 // fold operands of sext_in_reg based on knowledge that the top bits are not
5197 // demanded.
Dan Gohman475871a2008-07-27 21:46:04 +00005198 if (SimplifyDemandedBits(SDValue(N, 0)))
5199 return SDValue(N, 0);
Scott Michelfdc40a02009-02-17 22:15:04 +00005200
Evan Chengc88138f2007-03-22 01:54:19 +00005201 // fold (sext_in_reg (load x)) -> (smaller sextload x)
5202 // fold (sext_in_reg (srl (load x), c)) -> (smaller sextload (x+c/evtbits))
Dan Gohman475871a2008-07-27 21:46:04 +00005203 SDValue NarrowLoad = ReduceLoadWidth(N);
Gabor Greifba36cb52008-08-28 21:40:38 +00005204 if (NarrowLoad.getNode())
Evan Chengc88138f2007-03-22 01:54:19 +00005205 return NarrowLoad;
5206
Bill Wendling8509c902009-01-30 22:33:24 +00005207 // fold (sext_in_reg (srl X, 24), i8) -> (sra X, 24)
Sylvestre Ledru94c22712012-09-27 10:14:43 +00005208 // fold (sext_in_reg (srl X, 23), i8) -> (sra X, 23) iff possible.
Chris Lattner4b37e872006-05-08 21:18:59 +00005209 // We already fold "(sext_in_reg (srl X, 25), i8) -> srl X, 25" above.
5210 if (N0.getOpcode() == ISD::SRL) {
5211 if (ConstantSDNode *ShAmt = dyn_cast<ConstantSDNode>(N0.getOperand(1)))
Dan Gohman87862e72009-12-11 21:31:27 +00005212 if (ShAmt->getZExtValue()+EVTBits <= VTBits) {
Sylvestre Ledru94c22712012-09-27 10:14:43 +00005213 // We can turn this into an SRA iff the input to the SRL is already sign
Chris Lattner4b37e872006-05-08 21:18:59 +00005214 // extended enough.
Dan Gohmanea859be2007-06-22 14:59:07 +00005215 unsigned InSignBits = DAG.ComputeNumSignBits(N0.getOperand(0));
Dan Gohman87862e72009-12-11 21:31:27 +00005216 if (VTBits-(ShAmt->getZExtValue()+EVTBits) < InSignBits)
Bill Wendling8509c902009-01-30 22:33:24 +00005217 return DAG.getNode(ISD::SRA, N->getDebugLoc(), VT,
5218 N0.getOperand(0), N0.getOperand(1));
Chris Lattner4b37e872006-05-08 21:18:59 +00005219 }
5220 }
Evan Chengc88138f2007-03-22 01:54:19 +00005221
Nate Begemanded49632005-10-13 03:11:28 +00005222 // fold (sext_inreg (extload x)) -> (sextload x)
Scott Michelfdc40a02009-02-17 22:15:04 +00005223 if (ISD::isEXTLoad(N0.getNode()) &&
Gabor Greifba36cb52008-08-28 21:40:38 +00005224 ISD::isUNINDEXEDLoad(N0.getNode()) &&
Dan Gohmanb625f2f2008-01-30 00:15:11 +00005225 EVT == cast<LoadSDNode>(N0)->getMemoryVT() &&
Duncan Sands25cf2272008-11-24 14:53:14 +00005226 ((!LegalOperations && !cast<LoadSDNode>(N0)->isVolatile()) ||
Evan Cheng03294662008-10-14 21:26:46 +00005227 TLI.isLoadExtLegal(ISD::SEXTLOAD, EVT))) {
Evan Cheng466685d2006-10-09 20:57:25 +00005228 LoadSDNode *LN0 = cast<LoadSDNode>(N0);
Stuart Hastingsa9011292011-02-16 16:23:55 +00005229 SDValue ExtLoad = DAG.getExtLoad(ISD::SEXTLOAD, N->getDebugLoc(), VT,
Bill Wendling8509c902009-01-30 22:33:24 +00005230 LN0->getChain(),
Chris Lattner3d6ccfb2010-09-21 17:04:51 +00005231 LN0->getBasePtr(), LN0->getPointerInfo(),
5232 EVT,
David Greene1e559442010-02-15 17:00:31 +00005233 LN0->isVolatile(), LN0->isNonTemporal(),
5234 LN0->getAlignment());
Chris Lattnerd4771842005-12-14 19:25:30 +00005235 CombineTo(N, ExtLoad);
Gabor Greifba36cb52008-08-28 21:40:38 +00005236 CombineTo(N0.getNode(), ExtLoad, ExtLoad.getValue(1));
Dan Gohman475871a2008-07-27 21:46:04 +00005237 return SDValue(N, 0); // Return N so it doesn't get rechecked!
Nate Begemanded49632005-10-13 03:11:28 +00005238 }
Sylvestre Ledru94c22712012-09-27 10:14:43 +00005239 // fold (sext_inreg (zextload x)) -> (sextload x) iff load has one use
Gabor Greifba36cb52008-08-28 21:40:38 +00005240 if (ISD::isZEXTLoad(N0.getNode()) && ISD::isUNINDEXEDLoad(N0.getNode()) &&
Evan Cheng83060c52007-03-07 08:07:03 +00005241 N0.hasOneUse() &&
Dan Gohmanb625f2f2008-01-30 00:15:11 +00005242 EVT == cast<LoadSDNode>(N0)->getMemoryVT() &&
Duncan Sands25cf2272008-11-24 14:53:14 +00005243 ((!LegalOperations && !cast<LoadSDNode>(N0)->isVolatile()) ||
Evan Cheng03294662008-10-14 21:26:46 +00005244 TLI.isLoadExtLegal(ISD::SEXTLOAD, EVT))) {
Evan Cheng466685d2006-10-09 20:57:25 +00005245 LoadSDNode *LN0 = cast<LoadSDNode>(N0);
Stuart Hastingsa9011292011-02-16 16:23:55 +00005246 SDValue ExtLoad = DAG.getExtLoad(ISD::SEXTLOAD, N->getDebugLoc(), VT,
Bill Wendling8509c902009-01-30 22:33:24 +00005247 LN0->getChain(),
Chris Lattner3d6ccfb2010-09-21 17:04:51 +00005248 LN0->getBasePtr(), LN0->getPointerInfo(),
5249 EVT,
David Greene1e559442010-02-15 17:00:31 +00005250 LN0->isVolatile(), LN0->isNonTemporal(),
5251 LN0->getAlignment());
Chris Lattnerd4771842005-12-14 19:25:30 +00005252 CombineTo(N, ExtLoad);
Gabor Greifba36cb52008-08-28 21:40:38 +00005253 CombineTo(N0.getNode(), ExtLoad, ExtLoad.getValue(1));
Dan Gohman475871a2008-07-27 21:46:04 +00005254 return SDValue(N, 0); // Return N so it doesn't get rechecked!
Nate Begemanded49632005-10-13 03:11:28 +00005255 }
Evan Cheng9568e5c2011-06-21 06:01:08 +00005256
5257 // Form (sext_inreg (bswap >> 16)) or (sext_inreg (rotl (bswap) 16))
5258 if (EVTBits <= 16 && N0.getOpcode() == ISD::OR) {
5259 SDValue BSwap = MatchBSwapHWordLow(N0.getNode(), N0.getOperand(0),
5260 N0.getOperand(1), false);
5261 if (BSwap.getNode() != 0)
5262 return DAG.getNode(ISD::SIGN_EXTEND_INREG, N->getDebugLoc(), VT,
5263 BSwap, N1);
5264 }
5265
Dan Gohman475871a2008-07-27 21:46:04 +00005266 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00005267}
5268
Dan Gohman475871a2008-07-27 21:46:04 +00005269SDValue DAGCombiner::visitTRUNCATE(SDNode *N) {
5270 SDValue N0 = N->getOperand(0);
Owen Andersone50ed302009-08-10 22:56:29 +00005271 EVT VT = N->getValueType(0);
Nadav Rotem7e413e9c2012-02-03 13:18:25 +00005272 bool isLE = TLI.isLittleEndian();
Nate Begeman1d4d4142005-09-01 00:19:25 +00005273
5274 // noop truncate
5275 if (N0.getValueType() == N->getValueType(0))
Nate Begeman83e75ec2005-09-06 04:43:02 +00005276 return N0;
Nate Begeman1d4d4142005-09-01 00:19:25 +00005277 // fold (truncate c1) -> c1
Chris Lattner310b5782006-05-06 23:06:26 +00005278 if (isa<ConstantSDNode>(N0))
Bill Wendling67a67682009-01-30 22:44:24 +00005279 return DAG.getNode(ISD::TRUNCATE, N->getDebugLoc(), VT, N0);
Nate Begeman1d4d4142005-09-01 00:19:25 +00005280 // fold (truncate (truncate x)) -> (truncate x)
5281 if (N0.getOpcode() == ISD::TRUNCATE)
Bill Wendling67a67682009-01-30 22:44:24 +00005282 return DAG.getNode(ISD::TRUNCATE, N->getDebugLoc(), VT, N0.getOperand(0));
Nate Begeman1d4d4142005-09-01 00:19:25 +00005283 // fold (truncate (ext x)) -> (ext x) or (truncate x) or x
Chris Lattner7f893c02010-04-07 18:13:33 +00005284 if (N0.getOpcode() == ISD::ZERO_EXTEND ||
5285 N0.getOpcode() == ISD::SIGN_EXTEND ||
Chris Lattnerb72773b2006-05-05 22:56:26 +00005286 N0.getOpcode() == ISD::ANY_EXTEND) {
Duncan Sands8e4eb092008-06-08 20:54:56 +00005287 if (N0.getOperand(0).getValueType().bitsLT(VT))
Nate Begeman1d4d4142005-09-01 00:19:25 +00005288 // if the source is smaller than the dest, we still need an extend
Bill Wendling67a67682009-01-30 22:44:24 +00005289 return DAG.getNode(N0.getOpcode(), N->getDebugLoc(), VT,
5290 N0.getOperand(0));
Craig Topper0eb5dad2012-09-29 07:18:53 +00005291 if (N0.getOperand(0).getValueType().bitsGT(VT))
Nate Begeman1d4d4142005-09-01 00:19:25 +00005292 // if the source is larger than the dest, than we just need the truncate
Bill Wendling67a67682009-01-30 22:44:24 +00005293 return DAG.getNode(ISD::TRUNCATE, N->getDebugLoc(), VT, N0.getOperand(0));
Craig Topper0eb5dad2012-09-29 07:18:53 +00005294 // if the source and dest are the same type, we can drop both the extend
5295 // and the truncate.
5296 return N0.getOperand(0);
Nate Begeman1d4d4142005-09-01 00:19:25 +00005297 }
Evan Cheng007b69e2007-03-21 20:14:05 +00005298
Nadav Rotemcc870a82012-02-05 11:39:23 +00005299 // Fold extract-and-trunc into a narrow extract. For example:
5300 // i64 x = EXTRACT_VECTOR_ELT(v2i64 val, i32 1)
5301 // i32 y = TRUNCATE(i64 x)
5302 // -- becomes --
5303 // v16i8 b = BITCAST (v2i64 val)
5304 // i8 x = EXTRACT_VECTOR_ELT(v16i8 b, i32 8)
5305 //
5306 // Note: We only run this optimization after type legalization (which often
Nadav Rotem7e413e9c2012-02-03 13:18:25 +00005307 // creates this pattern) and before operation legalization after which
5308 // we need to be more careful about the vector instructions that we generate.
5309 if (N0.getOpcode() == ISD::EXTRACT_VECTOR_ELT &&
5310 LegalTypes && !LegalOperations && N0->hasOneUse()) {
5311
5312 EVT VecTy = N0.getOperand(0).getValueType();
5313 EVT ExTy = N0.getValueType();
5314 EVT TrTy = N->getValueType(0);
5315
5316 unsigned NumElem = VecTy.getVectorNumElements();
5317 unsigned SizeRatio = ExTy.getSizeInBits()/TrTy.getSizeInBits();
5318
5319 EVT NVT = EVT::getVectorVT(*DAG.getContext(), TrTy, SizeRatio * NumElem);
5320 assert(NVT.getSizeInBits() == VecTy.getSizeInBits() && "Invalid Size");
5321
5322 SDValue EltNo = N0->getOperand(1);
5323 if (isa<ConstantSDNode>(EltNo) && isTypeLegal(NVT)) {
5324 int Elt = cast<ConstantSDNode>(EltNo)->getZExtValue();
Jim Grosbacha249f7d2012-05-08 20:56:07 +00005325 EVT IndexTy = N0->getOperand(1).getValueType();
Nadav Rotem7e413e9c2012-02-03 13:18:25 +00005326 int Index = isLE ? (Elt*SizeRatio) : (Elt*SizeRatio + (SizeRatio-1));
5327
5328 SDValue V = DAG.getNode(ISD::BITCAST, N->getDebugLoc(),
5329 NVT, N0.getOperand(0));
5330
5331 return DAG.getNode(ISD::EXTRACT_VECTOR_ELT,
5332 N->getDebugLoc(), TrTy, V,
Jim Grosbacha249f7d2012-05-08 20:56:07 +00005333 DAG.getConstant(Index, IndexTy));
Nadav Rotem7e413e9c2012-02-03 13:18:25 +00005334 }
5335 }
5336
Chris Lattner2b4c2792007-10-13 06:35:54 +00005337 // See if we can simplify the input to this truncate through knowledge that
Nadav Rotem8c20ec52011-02-24 21:01:34 +00005338 // only the low bits are being used.
5339 // For example "trunc (or (shl x, 8), y)" // -> trunc y
Nadav Rotemfcd96192011-02-27 07:40:43 +00005340 // Currently we only perform this optimization on scalars because vectors
Nadav Rotem8c20ec52011-02-24 21:01:34 +00005341 // may have different active low bits.
5342 if (!VT.isVector()) {
5343 SDValue Shorter =
5344 GetDemandedBits(N0, APInt::getLowBitsSet(N0.getValueSizeInBits(),
5345 VT.getSizeInBits()));
5346 if (Shorter.getNode())
5347 return DAG.getNode(ISD::TRUNCATE, N->getDebugLoc(), VT, Shorter);
5348 }
Nate Begeman3df4d522005-10-12 20:40:40 +00005349 // fold (truncate (load x)) -> (smaller load x)
Evan Cheng007b69e2007-03-21 20:14:05 +00005350 // fold (truncate (srl (load x), c)) -> (smaller load (x+c/evtbits))
Dan Gohman4e39e9d2010-06-24 14:30:44 +00005351 if (!LegalTypes || TLI.isTypeDesirableForOp(N0.getOpcode(), VT)) {
5352 SDValue Reduced = ReduceLoadWidth(N);
5353 if (Reduced.getNode())
5354 return Reduced;
5355 }
Michael Liao07edaf32012-10-17 23:45:54 +00005356 // fold (trunc (concat ... x ...)) -> (concat ..., (trunc x), ...)),
5357 // where ... are all 'undef'.
5358 if (N0.getOpcode() == ISD::CONCAT_VECTORS && !LegalTypes) {
5359 SmallVector<EVT, 8> VTs;
5360 SDValue V;
5361 unsigned Idx = 0;
5362 unsigned NumDefs = 0;
5363
5364 for (unsigned i = 0, e = N0.getNumOperands(); i != e; ++i) {
5365 SDValue X = N0.getOperand(i);
5366 if (X.getOpcode() != ISD::UNDEF) {
5367 V = X;
5368 Idx = i;
5369 NumDefs++;
5370 }
5371 // Stop if more than one members are non-undef.
5372 if (NumDefs > 1)
5373 break;
5374 VTs.push_back(EVT::getVectorVT(*DAG.getContext(),
5375 VT.getVectorElementType(),
5376 X.getValueType().getVectorNumElements()));
5377 }
5378
5379 if (NumDefs == 0)
5380 return DAG.getUNDEF(VT);
5381
5382 if (NumDefs == 1) {
5383 assert(V.getNode() && "The single defined operand is empty!");
5384 SmallVector<SDValue, 8> Opnds;
5385 for (unsigned i = 0, e = VTs.size(); i != e; ++i) {
5386 if (i != Idx) {
5387 Opnds.push_back(DAG.getUNDEF(VTs[i]));
5388 continue;
5389 }
5390 SDValue NV = DAG.getNode(ISD::TRUNCATE, V.getDebugLoc(), VTs[i], V);
5391 AddToWorkList(NV.getNode());
5392 Opnds.push_back(NV);
5393 }
5394 return DAG.getNode(ISD::CONCAT_VECTORS, N->getDebugLoc(), VT,
5395 &Opnds[0], Opnds.size());
5396 }
5397 }
Dan Gohman4e39e9d2010-06-24 14:30:44 +00005398
5399 // Simplify the operands using demanded-bits information.
5400 if (!VT.isVector() &&
5401 SimplifyDemandedBits(SDValue(N, 0)))
5402 return SDValue(N, 0);
5403
Evan Chenge5b51ac2010-04-17 06:13:15 +00005404 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00005405}
5406
Evan Cheng9bfa03c2008-05-12 23:04:07 +00005407static SDNode *getBuildPairElt(SDNode *N, unsigned i) {
Dan Gohman475871a2008-07-27 21:46:04 +00005408 SDValue Elt = N->getOperand(i);
Evan Cheng9bfa03c2008-05-12 23:04:07 +00005409 if (Elt.getOpcode() != ISD::MERGE_VALUES)
Gabor Greifba36cb52008-08-28 21:40:38 +00005410 return Elt.getNode();
5411 return Elt.getOperand(Elt.getResNo()).getNode();
Evan Cheng9bfa03c2008-05-12 23:04:07 +00005412}
5413
5414/// CombineConsecutiveLoads - build_pair (load, load) -> load
Scott Michelfdc40a02009-02-17 22:15:04 +00005415/// if load locations are consecutive.
Owen Andersone50ed302009-08-10 22:56:29 +00005416SDValue DAGCombiner::CombineConsecutiveLoads(SDNode *N, EVT VT) {
Evan Cheng9bfa03c2008-05-12 23:04:07 +00005417 assert(N->getOpcode() == ISD::BUILD_PAIR);
5418
Nate Begemanabc01992009-06-05 21:37:30 +00005419 LoadSDNode *LD1 = dyn_cast<LoadSDNode>(getBuildPairElt(N, 0));
5420 LoadSDNode *LD2 = dyn_cast<LoadSDNode>(getBuildPairElt(N, 1));
Chris Lattnerfa459012010-09-21 16:08:50 +00005421 if (!LD1 || !LD2 || !ISD::isNON_EXTLoad(LD1) || !LD1->hasOneUse() ||
5422 LD1->getPointerInfo().getAddrSpace() !=
5423 LD2->getPointerInfo().getAddrSpace())
Dan Gohman475871a2008-07-27 21:46:04 +00005424 return SDValue();
Owen Andersone50ed302009-08-10 22:56:29 +00005425 EVT LD1VT = LD1->getValueType(0);
Bill Wendling67a67682009-01-30 22:44:24 +00005426
Evan Cheng9bfa03c2008-05-12 23:04:07 +00005427 if (ISD::isNON_EXTLoad(LD2) &&
5428 LD2->hasOneUse() &&
Duncan Sandsd4b9c172008-06-13 19:07:40 +00005429 // If both are volatile this would reduce the number of volatile loads.
5430 // If one is volatile it might be ok, but play conservative and bail out.
Nate Begemanabc01992009-06-05 21:37:30 +00005431 !LD1->isVolatile() &&
5432 !LD2->isVolatile() &&
Evan Cheng64fa4a92009-12-09 01:36:00 +00005433 DAG.isConsecutiveLoad(LD2, LD1, LD1VT.getSizeInBits()/8, 1)) {
Nate Begemanabc01992009-06-05 21:37:30 +00005434 unsigned Align = LD1->getAlignment();
Micah Villmow3574eca2012-10-08 16:38:25 +00005435 unsigned NewAlign = TLI.getDataLayout()->
Owen Anderson23b9b192009-08-12 00:36:31 +00005436 getABITypeAlignment(VT.getTypeForEVT(*DAG.getContext()));
Bill Wendling67a67682009-01-30 22:44:24 +00005437
Duncan Sandsd4b9c172008-06-13 19:07:40 +00005438 if (NewAlign <= Align &&
Duncan Sands25cf2272008-11-24 14:53:14 +00005439 (!LegalOperations || TLI.isOperationLegal(ISD::LOAD, VT)))
Nate Begemanabc01992009-06-05 21:37:30 +00005440 return DAG.getLoad(VT, N->getDebugLoc(), LD1->getChain(),
Chris Lattnerfa459012010-09-21 16:08:50 +00005441 LD1->getBasePtr(), LD1->getPointerInfo(),
Pete Cooperd752e0f2011-11-08 18:42:53 +00005442 false, false, false, Align);
Evan Cheng9bfa03c2008-05-12 23:04:07 +00005443 }
Bill Wendling67a67682009-01-30 22:44:24 +00005444
Dan Gohman475871a2008-07-27 21:46:04 +00005445 return SDValue();
Evan Cheng9bfa03c2008-05-12 23:04:07 +00005446}
5447
Wesley Peckbf17cfa2010-11-23 03:31:01 +00005448SDValue DAGCombiner::visitBITCAST(SDNode *N) {
Dan Gohman475871a2008-07-27 21:46:04 +00005449 SDValue N0 = N->getOperand(0);
Owen Andersone50ed302009-08-10 22:56:29 +00005450 EVT VT = N->getValueType(0);
Chris Lattner94683772005-12-23 05:30:37 +00005451
Dan Gohman7f321562007-06-25 16:23:39 +00005452 // If the input is a BUILD_VECTOR with all constant elements, fold this now.
5453 // Only do this before legalize, since afterward the target may be depending
5454 // on the bitconvert.
5455 // First check to see if this is all constant.
Duncan Sands25cf2272008-11-24 14:53:14 +00005456 if (!LegalTypes &&
Gabor Greifba36cb52008-08-28 21:40:38 +00005457 N0.getOpcode() == ISD::BUILD_VECTOR && N0.getNode()->hasOneUse() &&
Duncan Sands83ec4b62008-06-06 12:08:01 +00005458 VT.isVector()) {
Dan Gohman7f321562007-06-25 16:23:39 +00005459 bool isSimple = true;
5460 for (unsigned i = 0, e = N0.getNumOperands(); i != e; ++i)
5461 if (N0.getOperand(i).getOpcode() != ISD::UNDEF &&
5462 N0.getOperand(i).getOpcode() != ISD::Constant &&
5463 N0.getOperand(i).getOpcode() != ISD::ConstantFP) {
Scott Michelfdc40a02009-02-17 22:15:04 +00005464 isSimple = false;
Dan Gohman7f321562007-06-25 16:23:39 +00005465 break;
5466 }
Scott Michelfdc40a02009-02-17 22:15:04 +00005467
Owen Andersone50ed302009-08-10 22:56:29 +00005468 EVT DestEltVT = N->getValueType(0).getVectorElementType();
Duncan Sands83ec4b62008-06-06 12:08:01 +00005469 assert(!DestEltVT.isVector() &&
Dan Gohman7f321562007-06-25 16:23:39 +00005470 "Element type of vector ValueType must not be vector!");
Bill Wendling67a67682009-01-30 22:44:24 +00005471 if (isSimple)
Wesley Peckbf17cfa2010-11-23 03:31:01 +00005472 return ConstantFoldBITCASTofBUILD_VECTOR(N0.getNode(), DestEltVT);
Dan Gohman7f321562007-06-25 16:23:39 +00005473 }
Scott Michelfdc40a02009-02-17 22:15:04 +00005474
Dan Gohman3dd168d2008-09-05 01:58:21 +00005475 // If the input is a constant, let getNode fold it.
Chris Lattner94683772005-12-23 05:30:37 +00005476 if (isa<ConstantSDNode>(N0) || isa<ConstantFPSDNode>(N0)) {
Wesley Peckbf17cfa2010-11-23 03:31:01 +00005477 SDValue Res = DAG.getNode(ISD::BITCAST, N->getDebugLoc(), VT, N0);
Dan Gohmana407ca12009-08-10 23:15:10 +00005478 if (Res.getNode() != N) {
5479 if (!LegalOperations ||
5480 TLI.isOperationLegal(Res.getNode()->getOpcode(), VT))
5481 return Res;
5482
5483 // Folding it resulted in an illegal node, and it's too late to
5484 // do that. Clean up the old node and forego the transformation.
5485 // Ideally this won't happen very often, because instcombine
5486 // and the earlier dagcombine runs (where illegal nodes are
5487 // permitted) should have folded most of them already.
5488 DAG.DeleteNode(Res.getNode());
5489 }
Chris Lattner94683772005-12-23 05:30:37 +00005490 }
Scott Michelfdc40a02009-02-17 22:15:04 +00005491
Bill Wendling67a67682009-01-30 22:44:24 +00005492 // (conv (conv x, t1), t2) -> (conv x, t2)
Wesley Peckbf17cfa2010-11-23 03:31:01 +00005493 if (N0.getOpcode() == ISD::BITCAST)
5494 return DAG.getNode(ISD::BITCAST, N->getDebugLoc(), VT,
Bill Wendling67a67682009-01-30 22:44:24 +00005495 N0.getOperand(0));
Chris Lattner6258fb22006-04-02 02:53:43 +00005496
Chris Lattner57104102005-12-23 05:44:41 +00005497 // fold (conv (load x)) -> (load (conv*)x)
Evan Cheng513da432007-10-06 08:19:55 +00005498 // If the resultant load doesn't need a higher alignment than the original!
Gabor Greifba36cb52008-08-28 21:40:38 +00005499 if (ISD::isNormalLoad(N0.getNode()) && N0.hasOneUse() &&
Duncan Sandsd4b9c172008-06-13 19:07:40 +00005500 // Do not change the width of a volatile load.
5501 !cast<LoadSDNode>(N0)->isVolatile() &&
Duncan Sands25cf2272008-11-24 14:53:14 +00005502 (!LegalOperations || TLI.isOperationLegal(ISD::LOAD, VT))) {
Evan Cheng466685d2006-10-09 20:57:25 +00005503 LoadSDNode *LN0 = cast<LoadSDNode>(N0);
Micah Villmow3574eca2012-10-08 16:38:25 +00005504 unsigned Align = TLI.getDataLayout()->
Owen Anderson23b9b192009-08-12 00:36:31 +00005505 getABITypeAlignment(VT.getTypeForEVT(*DAG.getContext()));
Evan Cheng59d5b682007-05-07 21:27:48 +00005506 unsigned OrigAlign = LN0->getAlignment();
Bill Wendling67a67682009-01-30 22:44:24 +00005507
Evan Cheng59d5b682007-05-07 21:27:48 +00005508 if (Align <= OrigAlign) {
Bill Wendling67a67682009-01-30 22:44:24 +00005509 SDValue Load = DAG.getLoad(VT, N->getDebugLoc(), LN0->getChain(),
Chris Lattnerfa459012010-09-21 16:08:50 +00005510 LN0->getBasePtr(), LN0->getPointerInfo(),
David Greene1e559442010-02-15 17:00:31 +00005511 LN0->isVolatile(), LN0->isNonTemporal(),
Pete Cooperd752e0f2011-11-08 18:42:53 +00005512 LN0->isInvariant(), OrigAlign);
Evan Cheng59d5b682007-05-07 21:27:48 +00005513 AddToWorkList(N);
Gabor Greif12632d22008-08-30 19:29:20 +00005514 CombineTo(N0.getNode(),
Wesley Peckbf17cfa2010-11-23 03:31:01 +00005515 DAG.getNode(ISD::BITCAST, N0.getDebugLoc(),
Bill Wendling67a67682009-01-30 22:44:24 +00005516 N0.getValueType(), Load),
Evan Cheng59d5b682007-05-07 21:27:48 +00005517 Load.getValue(1));
5518 return Load;
5519 }
Chris Lattner57104102005-12-23 05:44:41 +00005520 }
Duncan Sandsd4b9c172008-06-13 19:07:40 +00005521
Bill Wendling67a67682009-01-30 22:44:24 +00005522 // fold (bitconvert (fneg x)) -> (xor (bitconvert x), signbit)
5523 // fold (bitconvert (fabs x)) -> (and (bitconvert x), (not signbit))
Chris Lattner3bd39d42008-01-27 17:42:27 +00005524 // This often reduces constant pool loads.
Owen Anderson29f60f32012-04-02 22:10:29 +00005525 if (((N0.getOpcode() == ISD::FNEG && !TLI.isFNegFree(VT)) ||
5526 (N0.getOpcode() == ISD::FABS && !TLI.isFAbsFree(VT))) &&
Nadav Rotem91a7e012012-09-13 14:54:28 +00005527 N0.getNode()->hasOneUse() && VT.isInteger() &&
5528 !VT.isVector() && !N0.getValueType().isVector()) {
Wesley Peckbf17cfa2010-11-23 03:31:01 +00005529 SDValue NewConv = DAG.getNode(ISD::BITCAST, N0.getDebugLoc(), VT,
Bill Wendling67a67682009-01-30 22:44:24 +00005530 N0.getOperand(0));
Gabor Greifba36cb52008-08-28 21:40:38 +00005531 AddToWorkList(NewConv.getNode());
Scott Michelfdc40a02009-02-17 22:15:04 +00005532
Duncan Sands83ec4b62008-06-06 12:08:01 +00005533 APInt SignBit = APInt::getSignBit(VT.getSizeInBits());
Chris Lattner3bd39d42008-01-27 17:42:27 +00005534 if (N0.getOpcode() == ISD::FNEG)
Bill Wendling67a67682009-01-30 22:44:24 +00005535 return DAG.getNode(ISD::XOR, N->getDebugLoc(), VT,
5536 NewConv, DAG.getConstant(SignBit, VT));
Chris Lattner3bd39d42008-01-27 17:42:27 +00005537 assert(N0.getOpcode() == ISD::FABS);
Bill Wendling67a67682009-01-30 22:44:24 +00005538 return DAG.getNode(ISD::AND, N->getDebugLoc(), VT,
5539 NewConv, DAG.getConstant(~SignBit, VT));
Chris Lattner3bd39d42008-01-27 17:42:27 +00005540 }
Scott Michelfdc40a02009-02-17 22:15:04 +00005541
Bill Wendling67a67682009-01-30 22:44:24 +00005542 // fold (bitconvert (fcopysign cst, x)) ->
5543 // (or (and (bitconvert x), sign), (and cst, (not sign)))
5544 // Note that we don't handle (copysign x, cst) because this can always be
5545 // folded to an fneg or fabs.
Gabor Greifba36cb52008-08-28 21:40:38 +00005546 if (N0.getOpcode() == ISD::FCOPYSIGN && N0.getNode()->hasOneUse() &&
Chris Lattnerf32aac32008-01-27 23:32:17 +00005547 isa<ConstantFPSDNode>(N0.getOperand(0)) &&
Duncan Sands83ec4b62008-06-06 12:08:01 +00005548 VT.isInteger() && !VT.isVector()) {
5549 unsigned OrigXWidth = N0.getOperand(1).getValueType().getSizeInBits();
Owen Anderson23b9b192009-08-12 00:36:31 +00005550 EVT IntXVT = EVT::getIntegerVT(*DAG.getContext(), OrigXWidth);
Chris Lattner2392ae72010-04-15 04:48:01 +00005551 if (isTypeLegal(IntXVT)) {
Wesley Peckbf17cfa2010-11-23 03:31:01 +00005552 SDValue X = DAG.getNode(ISD::BITCAST, N0.getDebugLoc(),
Bill Wendling67a67682009-01-30 22:44:24 +00005553 IntXVT, N0.getOperand(1));
Duncan Sands25cf2272008-11-24 14:53:14 +00005554 AddToWorkList(X.getNode());
Chris Lattner3bd39d42008-01-27 17:42:27 +00005555
Duncan Sands25cf2272008-11-24 14:53:14 +00005556 // If X has a different width than the result/lhs, sext it or truncate it.
5557 unsigned VTWidth = VT.getSizeInBits();
5558 if (OrigXWidth < VTWidth) {
Bill Wendling9729c5a2009-01-31 03:12:48 +00005559 X = DAG.getNode(ISD::SIGN_EXTEND, N->getDebugLoc(), VT, X);
Duncan Sands25cf2272008-11-24 14:53:14 +00005560 AddToWorkList(X.getNode());
5561 } else if (OrigXWidth > VTWidth) {
5562 // To get the sign bit in the right place, we have to shift it right
5563 // before truncating.
Bill Wendling9729c5a2009-01-31 03:12:48 +00005564 X = DAG.getNode(ISD::SRL, X.getDebugLoc(),
Bill Wendling67a67682009-01-30 22:44:24 +00005565 X.getValueType(), X,
Duncan Sands25cf2272008-11-24 14:53:14 +00005566 DAG.getConstant(OrigXWidth-VTWidth, X.getValueType()));
5567 AddToWorkList(X.getNode());
Bill Wendling9729c5a2009-01-31 03:12:48 +00005568 X = DAG.getNode(ISD::TRUNCATE, X.getDebugLoc(), VT, X);
Duncan Sands25cf2272008-11-24 14:53:14 +00005569 AddToWorkList(X.getNode());
5570 }
Scott Michelfdc40a02009-02-17 22:15:04 +00005571
Duncan Sands25cf2272008-11-24 14:53:14 +00005572 APInt SignBit = APInt::getSignBit(VT.getSizeInBits());
Bill Wendling9729c5a2009-01-31 03:12:48 +00005573 X = DAG.getNode(ISD::AND, X.getDebugLoc(), VT,
Bill Wendling67a67682009-01-30 22:44:24 +00005574 X, DAG.getConstant(SignBit, VT));
Duncan Sands25cf2272008-11-24 14:53:14 +00005575 AddToWorkList(X.getNode());
Chris Lattner3bd39d42008-01-27 17:42:27 +00005576
Wesley Peckbf17cfa2010-11-23 03:31:01 +00005577 SDValue Cst = DAG.getNode(ISD::BITCAST, N0.getDebugLoc(),
Bill Wendling67a67682009-01-30 22:44:24 +00005578 VT, N0.getOperand(0));
Bill Wendling9729c5a2009-01-31 03:12:48 +00005579 Cst = DAG.getNode(ISD::AND, Cst.getDebugLoc(), VT,
Bill Wendling67a67682009-01-30 22:44:24 +00005580 Cst, DAG.getConstant(~SignBit, VT));
Duncan Sands25cf2272008-11-24 14:53:14 +00005581 AddToWorkList(Cst.getNode());
Chris Lattner3bd39d42008-01-27 17:42:27 +00005582
Bill Wendling67a67682009-01-30 22:44:24 +00005583 return DAG.getNode(ISD::OR, N->getDebugLoc(), VT, X, Cst);
Duncan Sands25cf2272008-11-24 14:53:14 +00005584 }
Chris Lattner3bd39d42008-01-27 17:42:27 +00005585 }
Evan Cheng9bfa03c2008-05-12 23:04:07 +00005586
Sylvestre Ledru94c22712012-09-27 10:14:43 +00005587 // bitconvert(build_pair(ld, ld)) -> ld iff load locations are consecutive.
Evan Cheng9bfa03c2008-05-12 23:04:07 +00005588 if (N0.getOpcode() == ISD::BUILD_PAIR) {
Gabor Greifba36cb52008-08-28 21:40:38 +00005589 SDValue CombineLD = CombineConsecutiveLoads(N0.getNode(), VT);
5590 if (CombineLD.getNode())
Evan Cheng9bfa03c2008-05-12 23:04:07 +00005591 return CombineLD;
5592 }
Scott Michelfdc40a02009-02-17 22:15:04 +00005593
Dan Gohman475871a2008-07-27 21:46:04 +00005594 return SDValue();
Chris Lattner94683772005-12-23 05:30:37 +00005595}
5596
Dan Gohman475871a2008-07-27 21:46:04 +00005597SDValue DAGCombiner::visitBUILD_PAIR(SDNode *N) {
Owen Andersone50ed302009-08-10 22:56:29 +00005598 EVT VT = N->getValueType(0);
Evan Cheng9bfa03c2008-05-12 23:04:07 +00005599 return CombineConsecutiveLoads(N, VT);
5600}
5601
Wesley Peckbf17cfa2010-11-23 03:31:01 +00005602/// ConstantFoldBITCASTofBUILD_VECTOR - We know that BV is a build_vector
Scott Michelfdc40a02009-02-17 22:15:04 +00005603/// node with Constant, ConstantFP or Undef operands. DstEltVT indicates the
Chris Lattner6258fb22006-04-02 02:53:43 +00005604/// destination element value type.
Dan Gohman475871a2008-07-27 21:46:04 +00005605SDValue DAGCombiner::
Wesley Peckbf17cfa2010-11-23 03:31:01 +00005606ConstantFoldBITCASTofBUILD_VECTOR(SDNode *BV, EVT DstEltVT) {
Owen Andersone50ed302009-08-10 22:56:29 +00005607 EVT SrcEltVT = BV->getValueType(0).getVectorElementType();
Scott Michelfdc40a02009-02-17 22:15:04 +00005608
Chris Lattner6258fb22006-04-02 02:53:43 +00005609 // If this is already the right type, we're done.
Dan Gohman475871a2008-07-27 21:46:04 +00005610 if (SrcEltVT == DstEltVT) return SDValue(BV, 0);
Scott Michelfdc40a02009-02-17 22:15:04 +00005611
Duncan Sands83ec4b62008-06-06 12:08:01 +00005612 unsigned SrcBitSize = SrcEltVT.getSizeInBits();
5613 unsigned DstBitSize = DstEltVT.getSizeInBits();
Scott Michelfdc40a02009-02-17 22:15:04 +00005614
Chris Lattner6258fb22006-04-02 02:53:43 +00005615 // If this is a conversion of N elements of one type to N elements of another
5616 // type, convert each element. This handles FP<->INT cases.
5617 if (SrcBitSize == DstBitSize) {
Nate Begemane0efc212010-07-27 18:02:18 +00005618 EVT VT = EVT::getVectorVT(*DAG.getContext(), DstEltVT,
5619 BV->getValueType(0).getVectorNumElements());
5620
5621 // Due to the FP element handling below calling this routine recursively,
5622 // we can end up with a scalar-to-vector node here.
5623 if (BV->getOpcode() == ISD::SCALAR_TO_VECTOR)
Wesley Peckbf17cfa2010-11-23 03:31:01 +00005624 return DAG.getNode(ISD::SCALAR_TO_VECTOR, BV->getDebugLoc(), VT,
5625 DAG.getNode(ISD::BITCAST, BV->getDebugLoc(),
Nate Begemane0efc212010-07-27 18:02:18 +00005626 DstEltVT, BV->getOperand(0)));
Wesley Peckbf17cfa2010-11-23 03:31:01 +00005627
Dan Gohman475871a2008-07-27 21:46:04 +00005628 SmallVector<SDValue, 8> Ops;
Dan Gohman7f321562007-06-25 16:23:39 +00005629 for (unsigned i = 0, e = BV->getNumOperands(); i != e; ++i) {
Bob Wilsonb1303d02009-04-13 22:05:19 +00005630 SDValue Op = BV->getOperand(i);
5631 // If the vector element type is not legal, the BUILD_VECTOR operands
5632 // are promoted and implicitly truncated. Make that explicit here.
Bob Wilsonc8851652009-04-20 17:27:09 +00005633 if (Op.getValueType() != SrcEltVT)
5634 Op = DAG.getNode(ISD::TRUNCATE, BV->getDebugLoc(), SrcEltVT, Op);
Wesley Peckbf17cfa2010-11-23 03:31:01 +00005635 Ops.push_back(DAG.getNode(ISD::BITCAST, BV->getDebugLoc(),
Bob Wilsonb1303d02009-04-13 22:05:19 +00005636 DstEltVT, Op));
Gabor Greifba36cb52008-08-28 21:40:38 +00005637 AddToWorkList(Ops.back().getNode());
Chris Lattner3e104b12006-04-08 04:15:24 +00005638 }
Evan Chenga87008d2009-02-25 22:49:59 +00005639 return DAG.getNode(ISD::BUILD_VECTOR, BV->getDebugLoc(), VT,
5640 &Ops[0], Ops.size());
Chris Lattner6258fb22006-04-02 02:53:43 +00005641 }
Scott Michelfdc40a02009-02-17 22:15:04 +00005642
Chris Lattner6258fb22006-04-02 02:53:43 +00005643 // Otherwise, we're growing or shrinking the elements. To avoid having to
5644 // handle annoying details of growing/shrinking FP values, we convert them to
5645 // int first.
Duncan Sands83ec4b62008-06-06 12:08:01 +00005646 if (SrcEltVT.isFloatingPoint()) {
Chris Lattner6258fb22006-04-02 02:53:43 +00005647 // Convert the input float vector to a int vector where the elements are the
5648 // same sizes.
Owen Anderson825b72b2009-08-11 20:47:22 +00005649 assert((SrcEltVT == MVT::f32 || SrcEltVT == MVT::f64) && "Unknown FP VT!");
Owen Anderson23b9b192009-08-12 00:36:31 +00005650 EVT IntVT = EVT::getIntegerVT(*DAG.getContext(), SrcEltVT.getSizeInBits());
Wesley Peckbf17cfa2010-11-23 03:31:01 +00005651 BV = ConstantFoldBITCASTofBUILD_VECTOR(BV, IntVT).getNode();
Chris Lattner6258fb22006-04-02 02:53:43 +00005652 SrcEltVT = IntVT;
5653 }
Scott Michelfdc40a02009-02-17 22:15:04 +00005654
Chris Lattner6258fb22006-04-02 02:53:43 +00005655 // Now we know the input is an integer vector. If the output is a FP type,
5656 // convert to integer first, then to FP of the right size.
Duncan Sands83ec4b62008-06-06 12:08:01 +00005657 if (DstEltVT.isFloatingPoint()) {
Owen Anderson825b72b2009-08-11 20:47:22 +00005658 assert((DstEltVT == MVT::f32 || DstEltVT == MVT::f64) && "Unknown FP VT!");
Owen Anderson23b9b192009-08-12 00:36:31 +00005659 EVT TmpVT = EVT::getIntegerVT(*DAG.getContext(), DstEltVT.getSizeInBits());
Wesley Peckbf17cfa2010-11-23 03:31:01 +00005660 SDNode *Tmp = ConstantFoldBITCASTofBUILD_VECTOR(BV, TmpVT).getNode();
Scott Michelfdc40a02009-02-17 22:15:04 +00005661
Chris Lattner6258fb22006-04-02 02:53:43 +00005662 // Next, convert to FP elements of the same size.
Wesley Peckbf17cfa2010-11-23 03:31:01 +00005663 return ConstantFoldBITCASTofBUILD_VECTOR(Tmp, DstEltVT);
Chris Lattner6258fb22006-04-02 02:53:43 +00005664 }
Scott Michelfdc40a02009-02-17 22:15:04 +00005665
Chris Lattner6258fb22006-04-02 02:53:43 +00005666 // Okay, we know the src/dst types are both integers of differing types.
5667 // Handling growing first.
Duncan Sands83ec4b62008-06-06 12:08:01 +00005668 assert(SrcEltVT.isInteger() && DstEltVT.isInteger());
Chris Lattner6258fb22006-04-02 02:53:43 +00005669 if (SrcBitSize < DstBitSize) {
5670 unsigned NumInputsPerOutput = DstBitSize/SrcBitSize;
Scott Michelfdc40a02009-02-17 22:15:04 +00005671
Dan Gohman475871a2008-07-27 21:46:04 +00005672 SmallVector<SDValue, 8> Ops;
Dan Gohman7f321562007-06-25 16:23:39 +00005673 for (unsigned i = 0, e = BV->getNumOperands(); i != e;
Chris Lattner6258fb22006-04-02 02:53:43 +00005674 i += NumInputsPerOutput) {
5675 bool isLE = TLI.isLittleEndian();
Dan Gohman220a8232008-03-03 23:51:38 +00005676 APInt NewBits = APInt(DstBitSize, 0);
Chris Lattner6258fb22006-04-02 02:53:43 +00005677 bool EltIsUndef = true;
5678 for (unsigned j = 0; j != NumInputsPerOutput; ++j) {
5679 // Shift the previously computed bits over.
5680 NewBits <<= SrcBitSize;
Dan Gohman475871a2008-07-27 21:46:04 +00005681 SDValue Op = BV->getOperand(i+ (isLE ? (NumInputsPerOutput-j-1) : j));
Chris Lattner6258fb22006-04-02 02:53:43 +00005682 if (Op.getOpcode() == ISD::UNDEF) continue;
5683 EltIsUndef = false;
Scott Michelfdc40a02009-02-17 22:15:04 +00005684
Jay Foad40f8f622010-12-07 08:25:19 +00005685 NewBits |= cast<ConstantSDNode>(Op)->getAPIntValue().
Dan Gohman58c25872010-04-12 02:24:01 +00005686 zextOrTrunc(SrcBitSize).zext(DstBitSize);
Chris Lattner6258fb22006-04-02 02:53:43 +00005687 }
Scott Michelfdc40a02009-02-17 22:15:04 +00005688
Chris Lattner6258fb22006-04-02 02:53:43 +00005689 if (EltIsUndef)
Dale Johannesene8d72302009-02-06 23:05:02 +00005690 Ops.push_back(DAG.getUNDEF(DstEltVT));
Chris Lattner6258fb22006-04-02 02:53:43 +00005691 else
5692 Ops.push_back(DAG.getConstant(NewBits, DstEltVT));
5693 }
5694
Owen Anderson23b9b192009-08-12 00:36:31 +00005695 EVT VT = EVT::getVectorVT(*DAG.getContext(), DstEltVT, Ops.size());
Evan Chenga87008d2009-02-25 22:49:59 +00005696 return DAG.getNode(ISD::BUILD_VECTOR, BV->getDebugLoc(), VT,
5697 &Ops[0], Ops.size());
Chris Lattner6258fb22006-04-02 02:53:43 +00005698 }
Scott Michelfdc40a02009-02-17 22:15:04 +00005699
Chris Lattner6258fb22006-04-02 02:53:43 +00005700 // Finally, this must be the case where we are shrinking elements: each input
5701 // turns into multiple outputs.
Evan Chengefec7512008-02-18 23:04:32 +00005702 bool isS2V = ISD::isScalarToVector(BV);
Chris Lattner6258fb22006-04-02 02:53:43 +00005703 unsigned NumOutputsPerInput = SrcBitSize/DstBitSize;
Owen Anderson23b9b192009-08-12 00:36:31 +00005704 EVT VT = EVT::getVectorVT(*DAG.getContext(), DstEltVT,
5705 NumOutputsPerInput*BV->getNumOperands());
Dan Gohman475871a2008-07-27 21:46:04 +00005706 SmallVector<SDValue, 8> Ops;
Bill Wendlingb0162f52009-01-30 22:53:48 +00005707
Dan Gohman7f321562007-06-25 16:23:39 +00005708 for (unsigned i = 0, e = BV->getNumOperands(); i != e; ++i) {
Chris Lattner6258fb22006-04-02 02:53:43 +00005709 if (BV->getOperand(i).getOpcode() == ISD::UNDEF) {
5710 for (unsigned j = 0; j != NumOutputsPerInput; ++j)
Dale Johannesene8d72302009-02-06 23:05:02 +00005711 Ops.push_back(DAG.getUNDEF(DstEltVT));
Chris Lattner6258fb22006-04-02 02:53:43 +00005712 continue;
5713 }
Bill Wendlingb0162f52009-01-30 22:53:48 +00005714
Jay Foad40f8f622010-12-07 08:25:19 +00005715 APInt OpVal = cast<ConstantSDNode>(BV->getOperand(i))->
5716 getAPIntValue().zextOrTrunc(SrcBitSize);
Bill Wendlingb0162f52009-01-30 22:53:48 +00005717
Chris Lattner6258fb22006-04-02 02:53:43 +00005718 for (unsigned j = 0; j != NumOutputsPerInput; ++j) {
Jay Foad40f8f622010-12-07 08:25:19 +00005719 APInt ThisVal = OpVal.trunc(DstBitSize);
Chris Lattner6258fb22006-04-02 02:53:43 +00005720 Ops.push_back(DAG.getConstant(ThisVal, DstEltVT));
Jay Foad40f8f622010-12-07 08:25:19 +00005721 if (isS2V && i == 0 && j == 0 && ThisVal.zext(SrcBitSize) == OpVal)
Evan Chengefec7512008-02-18 23:04:32 +00005722 // Simply turn this into a SCALAR_TO_VECTOR of the new type.
Bill Wendlingb0162f52009-01-30 22:53:48 +00005723 return DAG.getNode(ISD::SCALAR_TO_VECTOR, BV->getDebugLoc(), VT,
5724 Ops[0]);
Dan Gohman220a8232008-03-03 23:51:38 +00005725 OpVal = OpVal.lshr(DstBitSize);
Chris Lattner6258fb22006-04-02 02:53:43 +00005726 }
5727
5728 // For big endian targets, swap the order of the pieces of each element.
Duncan Sands0753fc12008-02-11 10:37:04 +00005729 if (TLI.isBigEndian())
Chris Lattner6258fb22006-04-02 02:53:43 +00005730 std::reverse(Ops.end()-NumOutputsPerInput, Ops.end());
5731 }
Bill Wendlingb0162f52009-01-30 22:53:48 +00005732
Evan Chenga87008d2009-02-25 22:49:59 +00005733 return DAG.getNode(ISD::BUILD_VECTOR, BV->getDebugLoc(), VT,
5734 &Ops[0], Ops.size());
Chris Lattner6258fb22006-04-02 02:53:43 +00005735}
5736
Dan Gohman475871a2008-07-27 21:46:04 +00005737SDValue DAGCombiner::visitFADD(SDNode *N) {
5738 SDValue N0 = N->getOperand(0);
5739 SDValue N1 = N->getOperand(1);
Nate Begemana0e221d2005-10-18 00:28:13 +00005740 ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(N0);
5741 ConstantFPSDNode *N1CFP = dyn_cast<ConstantFPSDNode>(N1);
Owen Andersone50ed302009-08-10 22:56:29 +00005742 EVT VT = N->getValueType(0);
Scott Michelfdc40a02009-02-17 22:15:04 +00005743
Dan Gohman7f321562007-06-25 16:23:39 +00005744 // fold vector ops
Duncan Sands83ec4b62008-06-06 12:08:01 +00005745 if (VT.isVector()) {
Dan Gohman475871a2008-07-27 21:46:04 +00005746 SDValue FoldedVOp = SimplifyVBinOp(N);
Gabor Greifba36cb52008-08-28 21:40:38 +00005747 if (FoldedVOp.getNode()) return FoldedVOp;
Dan Gohman05d92fe2007-07-13 20:03:40 +00005748 }
Scott Michelfdc40a02009-02-17 22:15:04 +00005749
Lang Hames01806942012-06-14 20:37:15 +00005750 // fold (fadd c1, c2) -> c1 + c2
Ulrich Weigande669c932012-10-29 18:35:49 +00005751 if (N0CFP && N1CFP)
Bill Wendlingb0162f52009-01-30 22:53:48 +00005752 return DAG.getNode(ISD::FADD, N->getDebugLoc(), VT, N0, N1);
Nate Begemana0e221d2005-10-18 00:28:13 +00005753 // canonicalize constant to RHS
5754 if (N0CFP && !N1CFP)
Bill Wendlingb0162f52009-01-30 22:53:48 +00005755 return DAG.getNode(ISD::FADD, N->getDebugLoc(), VT, N1, N0);
5756 // fold (fadd A, 0) -> A
Nick Lewycky8a8d4792011-12-02 22:16:29 +00005757 if (DAG.getTarget().Options.UnsafeFPMath && N1CFP &&
5758 N1CFP->getValueAPF().isZero())
Dan Gohman760f86f2009-01-22 21:58:43 +00005759 return N0;
Bill Wendlingb0162f52009-01-30 22:53:48 +00005760 // fold (fadd A, (fneg B)) -> (fsub A, B)
Owen Andersonafd3d562012-03-06 00:29:31 +00005761 if ((!LegalOperations || TLI.isOperationLegalOrCustom(ISD::FSUB, VT)) &&
Nadav Rotem6dfabb62012-09-20 08:53:31 +00005762 isNegatibleForFree(N1, LegalOperations, TLI, &DAG.getTarget().Options) == 2)
Bill Wendlingb0162f52009-01-30 22:53:48 +00005763 return DAG.getNode(ISD::FSUB, N->getDebugLoc(), VT, N0,
Duncan Sands25cf2272008-11-24 14:53:14 +00005764 GetNegatedExpression(N1, DAG, LegalOperations));
Bill Wendlingb0162f52009-01-30 22:53:48 +00005765 // fold (fadd (fneg A), B) -> (fsub B, A)
Owen Andersonafd3d562012-03-06 00:29:31 +00005766 if ((!LegalOperations || TLI.isOperationLegalOrCustom(ISD::FSUB, VT)) &&
Nadav Rotem6dfabb62012-09-20 08:53:31 +00005767 isNegatibleForFree(N0, LegalOperations, TLI, &DAG.getTarget().Options) == 2)
Bill Wendlingb0162f52009-01-30 22:53:48 +00005768 return DAG.getNode(ISD::FSUB, N->getDebugLoc(), VT, N1,
Duncan Sands25cf2272008-11-24 14:53:14 +00005769 GetNegatedExpression(N0, DAG, LegalOperations));
Scott Michelfdc40a02009-02-17 22:15:04 +00005770
Chris Lattnerddae4bd2007-01-08 23:04:05 +00005771 // If allowed, fold (fadd (fadd x, c1), c2) -> (fadd x, (fadd c1, c2))
Nick Lewycky8a8d4792011-12-02 22:16:29 +00005772 if (DAG.getTarget().Options.UnsafeFPMath && N1CFP &&
5773 N0.getOpcode() == ISD::FADD && N0.getNode()->hasOneUse() &&
5774 isa<ConstantFPSDNode>(N0.getOperand(1)))
Bill Wendlingb0162f52009-01-30 22:53:48 +00005775 return DAG.getNode(ISD::FADD, N->getDebugLoc(), VT, N0.getOperand(0),
Bill Wendlingfc4b6772009-02-01 11:19:36 +00005776 DAG.getNode(ISD::FADD, N->getDebugLoc(), VT,
5777 N0.getOperand(1), N1));
Scott Michelfdc40a02009-02-17 22:15:04 +00005778
Owen Anderson607ebde2012-11-01 02:00:53 +00005779 // If allow, fold (fadd (fneg x), x) -> 0.0
5780 if (DAG.getTarget().Options.UnsafeFPMath &&
5781 N0.getOpcode() == ISD::FNEG && N0.getOperand(0) == N1) {
5782 return DAG.getConstantFP(0.0, VT);
5783 }
5784
5785 // If allow, fold (fadd x, (fneg x)) -> 0.0
5786 if (DAG.getTarget().Options.UnsafeFPMath &&
5787 N1.getOpcode() == ISD::FNEG && N1.getOperand(0) == N0) {
5788 return DAG.getConstantFP(0.0, VT);
5789 }
5790
Owen Anderson43da6c72012-08-30 23:35:16 +00005791 // In unsafe math mode, we can fold chains of FADD's of the same value
5792 // into multiplications. This transform is not safe in general because
5793 // we are reducing the number of rounding steps.
5794 if (DAG.getTarget().Options.UnsafeFPMath &&
5795 TLI.isOperationLegalOrCustom(ISD::FMUL, VT) &&
5796 !N0CFP && !N1CFP) {
5797 if (N0.getOpcode() == ISD::FMUL) {
5798 ConstantFPSDNode *CFP00 = dyn_cast<ConstantFPSDNode>(N0.getOperand(0));
5799 ConstantFPSDNode *CFP01 = dyn_cast<ConstantFPSDNode>(N0.getOperand(1));
5800
5801 // (fadd (fmul c, x), x) -> (fmul c+1, x)
5802 if (CFP00 && !CFP01 && N0.getOperand(1) == N1) {
5803 SDValue NewCFP = DAG.getNode(ISD::FADD, N->getDebugLoc(), VT,
5804 SDValue(CFP00, 0),
5805 DAG.getConstantFP(1.0, VT));
5806 return DAG.getNode(ISD::FMUL, N->getDebugLoc(), VT,
5807 N1, NewCFP);
5808 }
5809
5810 // (fadd (fmul x, c), x) -> (fmul c+1, x)
5811 if (CFP01 && !CFP00 && N0.getOperand(0) == N1) {
5812 SDValue NewCFP = DAG.getNode(ISD::FADD, N->getDebugLoc(), VT,
5813 SDValue(CFP01, 0),
5814 DAG.getConstantFP(1.0, VT));
5815 return DAG.getNode(ISD::FMUL, N->getDebugLoc(), VT,
5816 N1, NewCFP);
5817 }
5818
5819 // (fadd (fadd x, x), x) -> (fmul 3.0, x)
5820 if (!CFP00 && !CFP01 && N0.getOperand(0) == N0.getOperand(1) &&
5821 N0.getOperand(0) == N1) {
5822 return DAG.getNode(ISD::FMUL, N->getDebugLoc(), VT,
5823 N1, DAG.getConstantFP(3.0, VT));
5824 }
5825
5826 // (fadd (fmul c, x), (fadd x, x)) -> (fmul c+2, x)
5827 if (CFP00 && !CFP01 && N1.getOpcode() == ISD::FADD &&
5828 N1.getOperand(0) == N1.getOperand(1) &&
5829 N0.getOperand(1) == N1.getOperand(0)) {
5830 SDValue NewCFP = DAG.getNode(ISD::FADD, N->getDebugLoc(), VT,
5831 SDValue(CFP00, 0),
5832 DAG.getConstantFP(2.0, VT));
5833 return DAG.getNode(ISD::FMUL, N->getDebugLoc(), VT,
5834 N0.getOperand(1), NewCFP);
5835 }
5836
5837 // (fadd (fmul x, c), (fadd x, x)) -> (fmul c+2, x)
5838 if (CFP01 && !CFP00 && N1.getOpcode() == ISD::FADD &&
5839 N1.getOperand(0) == N1.getOperand(1) &&
5840 N0.getOperand(0) == N1.getOperand(0)) {
5841 SDValue NewCFP = DAG.getNode(ISD::FADD, N->getDebugLoc(), VT,
5842 SDValue(CFP01, 0),
5843 DAG.getConstantFP(2.0, VT));
5844 return DAG.getNode(ISD::FMUL, N->getDebugLoc(), VT,
5845 N0.getOperand(0), NewCFP);
5846 }
5847 }
5848
5849 if (N1.getOpcode() == ISD::FMUL) {
5850 ConstantFPSDNode *CFP10 = dyn_cast<ConstantFPSDNode>(N1.getOperand(0));
5851 ConstantFPSDNode *CFP11 = dyn_cast<ConstantFPSDNode>(N1.getOperand(1));
5852
5853 // (fadd x, (fmul c, x)) -> (fmul c+1, x)
5854 if (CFP10 && !CFP11 && N1.getOperand(1) == N0) {
5855 SDValue NewCFP = DAG.getNode(ISD::FADD, N->getDebugLoc(), VT,
5856 SDValue(CFP10, 0),
5857 DAG.getConstantFP(1.0, VT));
5858 return DAG.getNode(ISD::FMUL, N->getDebugLoc(), VT,
5859 N0, NewCFP);
5860 }
5861
5862 // (fadd x, (fmul x, c)) -> (fmul c+1, x)
5863 if (CFP11 && !CFP10 && N1.getOperand(0) == N0) {
5864 SDValue NewCFP = DAG.getNode(ISD::FADD, N->getDebugLoc(), VT,
5865 SDValue(CFP11, 0),
5866 DAG.getConstantFP(1.0, VT));
5867 return DAG.getNode(ISD::FMUL, N->getDebugLoc(), VT,
5868 N0, NewCFP);
5869 }
5870
5871 // (fadd x, (fadd x, x)) -> (fmul 3.0, x)
5872 if (!CFP10 && !CFP11 && N1.getOperand(0) == N1.getOperand(1) &&
5873 N1.getOperand(0) == N0) {
5874 return DAG.getNode(ISD::FMUL, N->getDebugLoc(), VT,
5875 N0, DAG.getConstantFP(3.0, VT));
5876 }
5877
5878 // (fadd (fadd x, x), (fmul c, x)) -> (fmul c+2, x)
5879 if (CFP10 && !CFP11 && N1.getOpcode() == ISD::FADD &&
5880 N1.getOperand(0) == N1.getOperand(1) &&
5881 N0.getOperand(1) == N1.getOperand(0)) {
5882 SDValue NewCFP = DAG.getNode(ISD::FADD, N->getDebugLoc(), VT,
5883 SDValue(CFP10, 0),
5884 DAG.getConstantFP(2.0, VT));
5885 return DAG.getNode(ISD::FMUL, N->getDebugLoc(), VT,
5886 N0.getOperand(1), NewCFP);
5887 }
5888
5889 // (fadd (fadd x, x), (fmul x, c)) -> (fmul c+2, x)
5890 if (CFP11 && !CFP10 && N1.getOpcode() == ISD::FADD &&
5891 N1.getOperand(0) == N1.getOperand(1) &&
5892 N0.getOperand(0) == N1.getOperand(0)) {
5893 SDValue NewCFP = DAG.getNode(ISD::FADD, N->getDebugLoc(), VT,
5894 SDValue(CFP11, 0),
5895 DAG.getConstantFP(2.0, VT));
5896 return DAG.getNode(ISD::FMUL, N->getDebugLoc(), VT,
5897 N0.getOperand(0), NewCFP);
5898 }
5899 }
5900
5901 // (fadd (fadd x, x), (fadd x, x)) -> (fmul 4.0, x)
5902 if (N0.getOpcode() == ISD::FADD && N1.getOpcode() == ISD::FADD &&
5903 N0.getOperand(0) == N0.getOperand(1) &&
5904 N1.getOperand(0) == N1.getOperand(1) &&
5905 N0.getOperand(0) == N1.getOperand(0)) {
5906 return DAG.getNode(ISD::FMUL, N->getDebugLoc(), VT,
5907 N0.getOperand(0),
5908 DAG.getConstantFP(4.0, VT));
5909 }
5910 }
5911
Lang Hamesd693caf2012-06-19 22:51:23 +00005912 // FADD -> FMA combines:
Lang Hamese0231412012-06-22 01:09:09 +00005913 if ((DAG.getTarget().Options.AllowFPOpFusion == FPOpFusion::Fast ||
Lang Hamesd693caf2012-06-19 22:51:23 +00005914 DAG.getTarget().Options.UnsafeFPMath) &&
5915 DAG.getTarget().getTargetLowering()->isFMAFasterThanMulAndAdd(VT) &&
Elena Demikhovsky1503aba2012-08-01 12:06:00 +00005916 TLI.isOperationLegalOrCustom(ISD::FMA, VT)) {
Lang Hamesd693caf2012-06-19 22:51:23 +00005917
5918 // fold (fadd (fmul x, y), z) -> (fma x, y, z)
5919 if (N0.getOpcode() == ISD::FMUL && N0->hasOneUse()) {
5920 return DAG.getNode(ISD::FMA, N->getDebugLoc(), VT,
5921 N0.getOperand(0), N0.getOperand(1), N1);
5922 }
Owen Anderson43da6c72012-08-30 23:35:16 +00005923
Michael Liaob79bff52012-09-01 04:09:16 +00005924 // fold (fadd x, (fmul y, z)) -> (fma y, z, x)
Lang Hamesd693caf2012-06-19 22:51:23 +00005925 // Note: Commutes FADD operands.
5926 if (N1.getOpcode() == ISD::FMUL && N1->hasOneUse()) {
5927 return DAG.getNode(ISD::FMA, N->getDebugLoc(), VT,
5928 N1.getOperand(0), N1.getOperand(1), N0);
5929 }
5930 }
5931
Dan Gohman475871a2008-07-27 21:46:04 +00005932 return SDValue();
Chris Lattner01b3d732005-09-28 22:28:18 +00005933}
5934
Dan Gohman475871a2008-07-27 21:46:04 +00005935SDValue DAGCombiner::visitFSUB(SDNode *N) {
5936 SDValue N0 = N->getOperand(0);
5937 SDValue N1 = N->getOperand(1);
Nate Begemana0e221d2005-10-18 00:28:13 +00005938 ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(N0);
5939 ConstantFPSDNode *N1CFP = dyn_cast<ConstantFPSDNode>(N1);
Owen Andersone50ed302009-08-10 22:56:29 +00005940 EVT VT = N->getValueType(0);
Elena Demikhovsky1503aba2012-08-01 12:06:00 +00005941 DebugLoc dl = N->getDebugLoc();
Scott Michelfdc40a02009-02-17 22:15:04 +00005942
Dan Gohman7f321562007-06-25 16:23:39 +00005943 // fold vector ops
Duncan Sands83ec4b62008-06-06 12:08:01 +00005944 if (VT.isVector()) {
Dan Gohman475871a2008-07-27 21:46:04 +00005945 SDValue FoldedVOp = SimplifyVBinOp(N);
Gabor Greifba36cb52008-08-28 21:40:38 +00005946 if (FoldedVOp.getNode()) return FoldedVOp;
Dan Gohman05d92fe2007-07-13 20:03:40 +00005947 }
Scott Michelfdc40a02009-02-17 22:15:04 +00005948
Nate Begemana0e221d2005-10-18 00:28:13 +00005949 // fold (fsub c1, c2) -> c1-c2
Ulrich Weigande669c932012-10-29 18:35:49 +00005950 if (N0CFP && N1CFP)
Bill Wendlingfc4b6772009-02-01 11:19:36 +00005951 return DAG.getNode(ISD::FSUB, N->getDebugLoc(), VT, N0, N1);
Bill Wendlingb0162f52009-01-30 22:53:48 +00005952 // fold (fsub A, 0) -> A
Nick Lewycky8a8d4792011-12-02 22:16:29 +00005953 if (DAG.getTarget().Options.UnsafeFPMath &&
5954 N1CFP && N1CFP->getValueAPF().isZero())
Dan Gohmana90c8e62009-01-23 19:10:37 +00005955 return N0;
Bill Wendlingb0162f52009-01-30 22:53:48 +00005956 // fold (fsub 0, B) -> -B
Nick Lewycky8a8d4792011-12-02 22:16:29 +00005957 if (DAG.getTarget().Options.UnsafeFPMath &&
5958 N0CFP && N0CFP->getValueAPF().isZero()) {
Owen Andersonafd3d562012-03-06 00:29:31 +00005959 if (isNegatibleForFree(N1, LegalOperations, TLI, &DAG.getTarget().Options))
Duncan Sands25cf2272008-11-24 14:53:14 +00005960 return GetNegatedExpression(N1, DAG, LegalOperations);
Dan Gohman760f86f2009-01-22 21:58:43 +00005961 if (!LegalOperations || TLI.isOperationLegal(ISD::FNEG, VT))
Elena Demikhovsky1503aba2012-08-01 12:06:00 +00005962 return DAG.getNode(ISD::FNEG, dl, VT, N1);
Dan Gohman23ff1822007-07-02 15:48:56 +00005963 }
Bill Wendlingb0162f52009-01-30 22:53:48 +00005964 // fold (fsub A, (fneg B)) -> (fadd A, B)
Owen Andersonafd3d562012-03-06 00:29:31 +00005965 if (isNegatibleForFree(N1, LegalOperations, TLI, &DAG.getTarget().Options))
Elena Demikhovsky1503aba2012-08-01 12:06:00 +00005966 return DAG.getNode(ISD::FADD, dl, VT, N0,
Duncan Sands25cf2272008-11-24 14:53:14 +00005967 GetNegatedExpression(N1, DAG, LegalOperations));
Scott Michelfdc40a02009-02-17 22:15:04 +00005968
Bill Wendling5a894342012-03-15 05:12:00 +00005969 // If 'unsafe math' is enabled, fold
Owen Anderson713e9532012-05-07 20:51:25 +00005970 // (fsub x, x) -> 0.0 &
Bill Wendling5a894342012-03-15 05:12:00 +00005971 // (fsub x, (fadd x, y)) -> (fneg y) &
5972 // (fsub x, (fadd y, x)) -> (fneg y)
5973 if (DAG.getTarget().Options.UnsafeFPMath) {
Owen Anderson713e9532012-05-07 20:51:25 +00005974 if (N0 == N1)
5975 return DAG.getConstantFP(0.0f, VT);
5976
Bill Wendling5a894342012-03-15 05:12:00 +00005977 if (N1.getOpcode() == ISD::FADD) {
5978 SDValue N10 = N1->getOperand(0);
5979 SDValue N11 = N1->getOperand(1);
5980
5981 if (N10 == N0 && isNegatibleForFree(N11, LegalOperations, TLI,
5982 &DAG.getTarget().Options))
5983 return GetNegatedExpression(N11, DAG, LegalOperations);
5984 else if (N11 == N0 && isNegatibleForFree(N10, LegalOperations, TLI,
5985 &DAG.getTarget().Options))
5986 return GetNegatedExpression(N10, DAG, LegalOperations);
5987 }
5988 }
5989
Lang Hamesd693caf2012-06-19 22:51:23 +00005990 // FSUB -> FMA combines:
Lang Hamese0231412012-06-22 01:09:09 +00005991 if ((DAG.getTarget().Options.AllowFPOpFusion == FPOpFusion::Fast ||
Lang Hamesd693caf2012-06-19 22:51:23 +00005992 DAG.getTarget().Options.UnsafeFPMath) &&
5993 DAG.getTarget().getTargetLowering()->isFMAFasterThanMulAndAdd(VT) &&
Elena Demikhovsky1503aba2012-08-01 12:06:00 +00005994 TLI.isOperationLegalOrCustom(ISD::FMA, VT)) {
Lang Hamesd693caf2012-06-19 22:51:23 +00005995
5996 // fold (fsub (fmul x, y), z) -> (fma x, y, (fneg z))
5997 if (N0.getOpcode() == ISD::FMUL && N0->hasOneUse()) {
Elena Demikhovsky1503aba2012-08-01 12:06:00 +00005998 return DAG.getNode(ISD::FMA, dl, VT,
Lang Hamesd693caf2012-06-19 22:51:23 +00005999 N0.getOperand(0), N0.getOperand(1),
Elena Demikhovsky1503aba2012-08-01 12:06:00 +00006000 DAG.getNode(ISD::FNEG, dl, VT, N1));
Lang Hamesd693caf2012-06-19 22:51:23 +00006001 }
6002
6003 // fold (fsub x, (fmul y, z)) -> (fma (fneg y), z, x)
6004 // Note: Commutes FSUB operands.
6005 if (N1.getOpcode() == ISD::FMUL && N1->hasOneUse()) {
Elena Demikhovsky1503aba2012-08-01 12:06:00 +00006006 return DAG.getNode(ISD::FMA, dl, VT,
6007 DAG.getNode(ISD::FNEG, dl, VT,
Lang Hamesd693caf2012-06-19 22:51:23 +00006008 N1.getOperand(0)),
6009 N1.getOperand(1), N0);
6010 }
Elena Demikhovsky1503aba2012-08-01 12:06:00 +00006011
6012 // fold (fsub (-(fmul, x, y)), z) -> (fma (fneg x), y, (fneg z))
6013 if (N0.getOpcode() == ISD::FNEG &&
6014 N0.getOperand(0).getOpcode() == ISD::FMUL &&
6015 N0->hasOneUse() && N0.getOperand(0).hasOneUse()) {
6016 SDValue N00 = N0.getOperand(0).getOperand(0);
6017 SDValue N01 = N0.getOperand(0).getOperand(1);
6018 return DAG.getNode(ISD::FMA, dl, VT,
6019 DAG.getNode(ISD::FNEG, dl, VT, N00), N01,
6020 DAG.getNode(ISD::FNEG, dl, VT, N1));
6021 }
Lang Hamesd693caf2012-06-19 22:51:23 +00006022 }
6023
Dan Gohman475871a2008-07-27 21:46:04 +00006024 return SDValue();
Chris Lattner01b3d732005-09-28 22:28:18 +00006025}
6026
Dan Gohman475871a2008-07-27 21:46:04 +00006027SDValue DAGCombiner::visitFMUL(SDNode *N) {
6028 SDValue N0 = N->getOperand(0);
6029 SDValue N1 = N->getOperand(1);
Nate Begeman11af4ea2005-10-17 20:40:11 +00006030 ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(N0);
6031 ConstantFPSDNode *N1CFP = dyn_cast<ConstantFPSDNode>(N1);
Owen Andersone50ed302009-08-10 22:56:29 +00006032 EVT VT = N->getValueType(0);
Owen Andersonafd3d562012-03-06 00:29:31 +00006033 const TargetLowering &TLI = DAG.getTargetLoweringInfo();
Chris Lattner01b3d732005-09-28 22:28:18 +00006034
Dan Gohman7f321562007-06-25 16:23:39 +00006035 // fold vector ops
Duncan Sands83ec4b62008-06-06 12:08:01 +00006036 if (VT.isVector()) {
Dan Gohman475871a2008-07-27 21:46:04 +00006037 SDValue FoldedVOp = SimplifyVBinOp(N);
Gabor Greifba36cb52008-08-28 21:40:38 +00006038 if (FoldedVOp.getNode()) return FoldedVOp;
Dan Gohman05d92fe2007-07-13 20:03:40 +00006039 }
Scott Michelfdc40a02009-02-17 22:15:04 +00006040
Nate Begeman11af4ea2005-10-17 20:40:11 +00006041 // fold (fmul c1, c2) -> c1*c2
Ulrich Weigande669c932012-10-29 18:35:49 +00006042 if (N0CFP && N1CFP)
Bill Wendlinga03e74b2009-01-30 22:57:07 +00006043 return DAG.getNode(ISD::FMUL, N->getDebugLoc(), VT, N0, N1);
Nate Begeman11af4ea2005-10-17 20:40:11 +00006044 // canonicalize constant to RHS
Nate Begemana0e221d2005-10-18 00:28:13 +00006045 if (N0CFP && !N1CFP)
Bill Wendlinga03e74b2009-01-30 22:57:07 +00006046 return DAG.getNode(ISD::FMUL, N->getDebugLoc(), VT, N1, N0);
6047 // fold (fmul A, 0) -> 0
Nick Lewycky8a8d4792011-12-02 22:16:29 +00006048 if (DAG.getTarget().Options.UnsafeFPMath &&
6049 N1CFP && N1CFP->getValueAPF().isZero())
Dan Gohman760f86f2009-01-22 21:58:43 +00006050 return N1;
Dan Gohman77b81fe2009-06-04 17:12:12 +00006051 // fold (fmul A, 0) -> 0, vector edition.
Nick Lewycky8a8d4792011-12-02 22:16:29 +00006052 if (DAG.getTarget().Options.UnsafeFPMath &&
6053 ISD::isBuildVectorAllZeros(N1.getNode()))
Dan Gohman77b81fe2009-06-04 17:12:12 +00006054 return N1;
Owen Anderson363e4b92012-05-02 21:32:35 +00006055 // fold (fmul A, 1.0) -> A
6056 if (N1CFP && N1CFP->isExactlyValue(1.0))
6057 return N0;
Nate Begeman11af4ea2005-10-17 20:40:11 +00006058 // fold (fmul X, 2.0) -> (fadd X, X)
6059 if (N1CFP && N1CFP->isExactlyValue(+2.0))
Bill Wendlinga03e74b2009-01-30 22:57:07 +00006060 return DAG.getNode(ISD::FADD, N->getDebugLoc(), VT, N0, N0);
Dan Gohmaneb1fedc2009-08-10 16:50:32 +00006061 // fold (fmul X, -1.0) -> (fneg X)
Chris Lattner29446522007-05-14 22:04:50 +00006062 if (N1CFP && N1CFP->isExactlyValue(-1.0))
Dan Gohman760f86f2009-01-22 21:58:43 +00006063 if (!LegalOperations || TLI.isOperationLegal(ISD::FNEG, VT))
Bill Wendlinga03e74b2009-01-30 22:57:07 +00006064 return DAG.getNode(ISD::FNEG, N->getDebugLoc(), VT, N0);
Scott Michelfdc40a02009-02-17 22:15:04 +00006065
Bill Wendlinga03e74b2009-01-30 22:57:07 +00006066 // fold (fmul (fneg X), (fneg Y)) -> (fmul X, Y)
Owen Andersonafd3d562012-03-06 00:29:31 +00006067 if (char LHSNeg = isNegatibleForFree(N0, LegalOperations, TLI,
Nick Lewycky8a8d4792011-12-02 22:16:29 +00006068 &DAG.getTarget().Options)) {
Owen Andersonafd3d562012-03-06 00:29:31 +00006069 if (char RHSNeg = isNegatibleForFree(N1, LegalOperations, TLI,
Nick Lewycky8a8d4792011-12-02 22:16:29 +00006070 &DAG.getTarget().Options)) {
Chris Lattner29446522007-05-14 22:04:50 +00006071 // Both can be negated for free, check to see if at least one is cheaper
6072 // negated.
6073 if (LHSNeg == 2 || RHSNeg == 2)
Bill Wendlinga03e74b2009-01-30 22:57:07 +00006074 return DAG.getNode(ISD::FMUL, N->getDebugLoc(), VT,
Duncan Sands25cf2272008-11-24 14:53:14 +00006075 GetNegatedExpression(N0, DAG, LegalOperations),
6076 GetNegatedExpression(N1, DAG, LegalOperations));
Chris Lattner29446522007-05-14 22:04:50 +00006077 }
6078 }
Scott Michelfdc40a02009-02-17 22:15:04 +00006079
Chris Lattnerddae4bd2007-01-08 23:04:05 +00006080 // If allowed, fold (fmul (fmul x, c1), c2) -> (fmul x, (fmul c1, c2))
Nick Lewycky8a8d4792011-12-02 22:16:29 +00006081 if (DAG.getTarget().Options.UnsafeFPMath &&
6082 N1CFP && N0.getOpcode() == ISD::FMUL &&
Gabor Greifba36cb52008-08-28 21:40:38 +00006083 N0.getNode()->hasOneUse() && isa<ConstantFPSDNode>(N0.getOperand(1)))
Bill Wendlinga03e74b2009-01-30 22:57:07 +00006084 return DAG.getNode(ISD::FMUL, N->getDebugLoc(), VT, N0.getOperand(0),
Scott Michelfdc40a02009-02-17 22:15:04 +00006085 DAG.getNode(ISD::FMUL, N->getDebugLoc(), VT,
Dale Johannesende064702009-02-06 21:50:26 +00006086 N0.getOperand(1), N1));
Scott Michelfdc40a02009-02-17 22:15:04 +00006087
Dan Gohman475871a2008-07-27 21:46:04 +00006088 return SDValue();
Chris Lattner01b3d732005-09-28 22:28:18 +00006089}
6090
Owen Anderson062c0a52012-05-02 22:17:40 +00006091SDValue DAGCombiner::visitFMA(SDNode *N) {
6092 SDValue N0 = N->getOperand(0);
6093 SDValue N1 = N->getOperand(1);
6094 SDValue N2 = N->getOperand(2);
6095 ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(N0);
6096 ConstantFPSDNode *N1CFP = dyn_cast<ConstantFPSDNode>(N1);
6097 EVT VT = N->getValueType(0);
Owen Anderson58d57292012-09-01 06:04:27 +00006098 DebugLoc dl = N->getDebugLoc();
Owen Anderson062c0a52012-05-02 22:17:40 +00006099
Owen Anderson607ebde2012-11-01 02:00:53 +00006100 if (DAG.getTarget().Options.UnsafeFPMath) {
6101 if (N0CFP && N0CFP->isZero())
6102 return N2;
6103 if (N1CFP && N1CFP->isZero())
6104 return N2;
6105 }
Owen Anderson062c0a52012-05-02 22:17:40 +00006106 if (N0CFP && N0CFP->isExactlyValue(1.0))
6107 return DAG.getNode(ISD::FADD, N->getDebugLoc(), VT, N1, N2);
6108 if (N1CFP && N1CFP->isExactlyValue(1.0))
6109 return DAG.getNode(ISD::FADD, N->getDebugLoc(), VT, N0, N2);
6110
Owen Anderson85ef6f42012-05-30 18:50:39 +00006111 // Canonicalize (fma c, x, y) -> (fma x, c, y)
Owen Andersonf917d202012-05-30 18:54:50 +00006112 if (N0CFP && !N1CFP)
Owen Anderson85ef6f42012-05-30 18:50:39 +00006113 return DAG.getNode(ISD::FMA, N->getDebugLoc(), VT, N1, N0, N2);
6114
Owen Anderson58d57292012-09-01 06:04:27 +00006115 // (fma x, c1, (fmul x, c2)) -> (fmul x, c1+c2)
6116 if (DAG.getTarget().Options.UnsafeFPMath && N1CFP &&
6117 N2.getOpcode() == ISD::FMUL &&
6118 N0 == N2.getOperand(0) &&
6119 N2.getOperand(1).getOpcode() == ISD::ConstantFP) {
6120 return DAG.getNode(ISD::FMUL, dl, VT, N0,
6121 DAG.getNode(ISD::FADD, dl, VT, N1, N2.getOperand(1)));
6122 }
6123
6124
6125 // (fma (fmul x, c1), c2, y) -> (fma x, c1*c2, y)
6126 if (DAG.getTarget().Options.UnsafeFPMath &&
6127 N0.getOpcode() == ISD::FMUL && N1CFP &&
6128 N0.getOperand(1).getOpcode() == ISD::ConstantFP) {
6129 return DAG.getNode(ISD::FMA, dl, VT,
6130 N0.getOperand(0),
6131 DAG.getNode(ISD::FMUL, dl, VT, N1, N0.getOperand(1)),
6132 N2);
6133 }
6134
6135 // (fma x, 1, y) -> (fadd x, y)
6136 // (fma x, -1, y) -> (fadd (fneg x), y)
6137 if (N1CFP) {
6138 if (N1CFP->isExactlyValue(1.0))
6139 return DAG.getNode(ISD::FADD, dl, VT, N0, N2);
6140
6141 if (N1CFP->isExactlyValue(-1.0) &&
6142 (!LegalOperations || TLI.isOperationLegal(ISD::FNEG, VT))) {
6143 SDValue RHSNeg = DAG.getNode(ISD::FNEG, dl, VT, N0);
6144 AddToWorkList(RHSNeg.getNode());
6145 return DAG.getNode(ISD::FADD, dl, VT, N2, RHSNeg);
6146 }
6147 }
6148
6149 // (fma x, c, x) -> (fmul x, (c+1))
6150 if (DAG.getTarget().Options.UnsafeFPMath && N1CFP && N0 == N2) {
6151 return DAG.getNode(ISD::FMUL, dl, VT,
6152 N0,
6153 DAG.getNode(ISD::FADD, dl, VT,
6154 N1, DAG.getConstantFP(1.0, VT)));
6155 }
6156
6157 // (fma x, c, (fneg x)) -> (fmul x, (c-1))
6158 if (DAG.getTarget().Options.UnsafeFPMath && N1CFP &&
6159 N2.getOpcode() == ISD::FNEG && N2.getOperand(0) == N0) {
6160 return DAG.getNode(ISD::FMUL, dl, VT,
6161 N0,
6162 DAG.getNode(ISD::FADD, dl, VT,
6163 N1, DAG.getConstantFP(-1.0, VT)));
6164 }
6165
6166
Owen Anderson062c0a52012-05-02 22:17:40 +00006167 return SDValue();
6168}
6169
Dan Gohman475871a2008-07-27 21:46:04 +00006170SDValue DAGCombiner::visitFDIV(SDNode *N) {
6171 SDValue N0 = N->getOperand(0);
6172 SDValue N1 = N->getOperand(1);
Nate Begemana148d982006-01-18 22:35:16 +00006173 ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(N0);
6174 ConstantFPSDNode *N1CFP = dyn_cast<ConstantFPSDNode>(N1);
Owen Andersone50ed302009-08-10 22:56:29 +00006175 EVT VT = N->getValueType(0);
Owen Andersonafd3d562012-03-06 00:29:31 +00006176 const TargetLowering &TLI = DAG.getTargetLoweringInfo();
Chris Lattner01b3d732005-09-28 22:28:18 +00006177
Dan Gohman7f321562007-06-25 16:23:39 +00006178 // fold vector ops
Duncan Sands83ec4b62008-06-06 12:08:01 +00006179 if (VT.isVector()) {
Dan Gohman475871a2008-07-27 21:46:04 +00006180 SDValue FoldedVOp = SimplifyVBinOp(N);
Gabor Greifba36cb52008-08-28 21:40:38 +00006181 if (FoldedVOp.getNode()) return FoldedVOp;
Dan Gohman05d92fe2007-07-13 20:03:40 +00006182 }
Scott Michelfdc40a02009-02-17 22:15:04 +00006183
Nate Begemana148d982006-01-18 22:35:16 +00006184 // fold (fdiv c1, c2) -> c1/c2
Ulrich Weigande669c932012-10-29 18:35:49 +00006185 if (N0CFP && N1CFP)
Bill Wendlinga03e74b2009-01-30 22:57:07 +00006186 return DAG.getNode(ISD::FDIV, N->getDebugLoc(), VT, N0, N1);
Scott Michelfdc40a02009-02-17 22:15:04 +00006187
Duncan Sands3ef3fcf2012-04-08 18:08:12 +00006188 // fold (fdiv X, c2) -> fmul X, 1/c2 if losing precision is acceptable.
Ulrich Weigande669c932012-10-29 18:35:49 +00006189 if (N1CFP && DAG.getTarget().Options.UnsafeFPMath) {
Duncan Sands961d6662012-04-07 20:04:00 +00006190 // Compute the reciprocal 1.0 / c2.
6191 APFloat N1APF = N1CFP->getValueAPF();
6192 APFloat Recip(N1APF.getSemantics(), 1); // 1.0
6193 APFloat::opStatus st = Recip.divide(N1APF, APFloat::rmNearestTiesToEven);
Duncan Sands507bb7a2012-04-10 20:35:27 +00006194 // Only do the transform if the reciprocal is a legal fp immediate that
6195 // isn't too nasty (eg NaN, denormal, ...).
6196 if ((st == APFloat::opOK || st == APFloat::opInexact) && // Not too nasty
Anton Korobeynikov999821c2012-04-10 13:22:49 +00006197 (!LegalOperations ||
6198 // FIXME: custom lowering of ConstantFP might fail (see e.g. ARM
6199 // backend)... we should handle this gracefully after Legalize.
6200 // TLI.isOperationLegalOrCustom(llvm::ISD::ConstantFP, VT) ||
6201 TLI.isOperationLegal(llvm::ISD::ConstantFP, VT) ||
6202 TLI.isFPImmLegal(Recip, VT)))
Duncan Sands961d6662012-04-07 20:04:00 +00006203 return DAG.getNode(ISD::FMUL, N->getDebugLoc(), VT, N0,
6204 DAG.getConstantFP(Recip, VT));
6205 }
Scott Michelfdc40a02009-02-17 22:15:04 +00006206
Bill Wendlinga03e74b2009-01-30 22:57:07 +00006207 // (fdiv (fneg X), (fneg Y)) -> (fdiv X, Y)
Owen Andersonafd3d562012-03-06 00:29:31 +00006208 if (char LHSNeg = isNegatibleForFree(N0, LegalOperations, TLI,
Nick Lewycky8a8d4792011-12-02 22:16:29 +00006209 &DAG.getTarget().Options)) {
Owen Andersonafd3d562012-03-06 00:29:31 +00006210 if (char RHSNeg = isNegatibleForFree(N1, LegalOperations, TLI,
Nick Lewycky8a8d4792011-12-02 22:16:29 +00006211 &DAG.getTarget().Options)) {
Chris Lattner29446522007-05-14 22:04:50 +00006212 // Both can be negated for free, check to see if at least one is cheaper
6213 // negated.
6214 if (LHSNeg == 2 || RHSNeg == 2)
Scott Michelfdc40a02009-02-17 22:15:04 +00006215 return DAG.getNode(ISD::FDIV, N->getDebugLoc(), VT,
Duncan Sands25cf2272008-11-24 14:53:14 +00006216 GetNegatedExpression(N0, DAG, LegalOperations),
6217 GetNegatedExpression(N1, DAG, LegalOperations));
Chris Lattner29446522007-05-14 22:04:50 +00006218 }
6219 }
Scott Michelfdc40a02009-02-17 22:15:04 +00006220
Dan Gohman475871a2008-07-27 21:46:04 +00006221 return SDValue();
Chris Lattner01b3d732005-09-28 22:28:18 +00006222}
6223
Dan Gohman475871a2008-07-27 21:46:04 +00006224SDValue DAGCombiner::visitFREM(SDNode *N) {
6225 SDValue N0 = N->getOperand(0);
6226 SDValue N1 = N->getOperand(1);
Nate Begemana148d982006-01-18 22:35:16 +00006227 ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(N0);
6228 ConstantFPSDNode *N1CFP = dyn_cast<ConstantFPSDNode>(N1);
Owen Andersone50ed302009-08-10 22:56:29 +00006229 EVT VT = N->getValueType(0);
Chris Lattner01b3d732005-09-28 22:28:18 +00006230
Nate Begemana148d982006-01-18 22:35:16 +00006231 // fold (frem c1, c2) -> fmod(c1,c2)
Ulrich Weigande669c932012-10-29 18:35:49 +00006232 if (N0CFP && N1CFP)
Bill Wendlinga03e74b2009-01-30 22:57:07 +00006233 return DAG.getNode(ISD::FREM, N->getDebugLoc(), VT, N0, N1);
Dan Gohman7f321562007-06-25 16:23:39 +00006234
Dan Gohman475871a2008-07-27 21:46:04 +00006235 return SDValue();
Chris Lattner01b3d732005-09-28 22:28:18 +00006236}
6237
Dan Gohman475871a2008-07-27 21:46:04 +00006238SDValue DAGCombiner::visitFCOPYSIGN(SDNode *N) {
6239 SDValue N0 = N->getOperand(0);
6240 SDValue N1 = N->getOperand(1);
Chris Lattner12d83032006-03-05 05:30:57 +00006241 ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(N0);
6242 ConstantFPSDNode *N1CFP = dyn_cast<ConstantFPSDNode>(N1);
Owen Andersone50ed302009-08-10 22:56:29 +00006243 EVT VT = N->getValueType(0);
Chris Lattner12d83032006-03-05 05:30:57 +00006244
Ulrich Weigande669c932012-10-29 18:35:49 +00006245 if (N0CFP && N1CFP) // Constant fold
Bill Wendlingfc4b6772009-02-01 11:19:36 +00006246 return DAG.getNode(ISD::FCOPYSIGN, N->getDebugLoc(), VT, N0, N1);
Scott Michelfdc40a02009-02-17 22:15:04 +00006247
Chris Lattner12d83032006-03-05 05:30:57 +00006248 if (N1CFP) {
Dale Johannesene6c17422007-08-26 01:18:27 +00006249 const APFloat& V = N1CFP->getValueAPF();
Sylvestre Ledru94c22712012-09-27 10:14:43 +00006250 // copysign(x, c1) -> fabs(x) iff ispos(c1)
6251 // copysign(x, c1) -> fneg(fabs(x)) iff isneg(c1)
Dan Gohman760f86f2009-01-22 21:58:43 +00006252 if (!V.isNegative()) {
6253 if (!LegalOperations || TLI.isOperationLegal(ISD::FABS, VT))
Bill Wendling0225a1d2009-01-30 23:15:49 +00006254 return DAG.getNode(ISD::FABS, N->getDebugLoc(), VT, N0);
Dan Gohman760f86f2009-01-22 21:58:43 +00006255 } else {
6256 if (!LegalOperations || TLI.isOperationLegal(ISD::FNEG, VT))
Bill Wendling0225a1d2009-01-30 23:15:49 +00006257 return DAG.getNode(ISD::FNEG, N->getDebugLoc(), VT,
Bill Wendling9729c5a2009-01-31 03:12:48 +00006258 DAG.getNode(ISD::FABS, N0.getDebugLoc(), VT, N0));
Dan Gohman760f86f2009-01-22 21:58:43 +00006259 }
Chris Lattner12d83032006-03-05 05:30:57 +00006260 }
Scott Michelfdc40a02009-02-17 22:15:04 +00006261
Chris Lattner12d83032006-03-05 05:30:57 +00006262 // copysign(fabs(x), y) -> copysign(x, y)
6263 // copysign(fneg(x), y) -> copysign(x, y)
6264 // copysign(copysign(x,z), y) -> copysign(x, y)
6265 if (N0.getOpcode() == ISD::FABS || N0.getOpcode() == ISD::FNEG ||
6266 N0.getOpcode() == ISD::FCOPYSIGN)
Bill Wendling0225a1d2009-01-30 23:15:49 +00006267 return DAG.getNode(ISD::FCOPYSIGN, N->getDebugLoc(), VT,
6268 N0.getOperand(0), N1);
Chris Lattner12d83032006-03-05 05:30:57 +00006269
6270 // copysign(x, abs(y)) -> abs(x)
6271 if (N1.getOpcode() == ISD::FABS)
Bill Wendling0225a1d2009-01-30 23:15:49 +00006272 return DAG.getNode(ISD::FABS, N->getDebugLoc(), VT, N0);
Scott Michelfdc40a02009-02-17 22:15:04 +00006273
Chris Lattner12d83032006-03-05 05:30:57 +00006274 // copysign(x, copysign(y,z)) -> copysign(x, z)
6275 if (N1.getOpcode() == ISD::FCOPYSIGN)
Bill Wendling0225a1d2009-01-30 23:15:49 +00006276 return DAG.getNode(ISD::FCOPYSIGN, N->getDebugLoc(), VT,
6277 N0, N1.getOperand(1));
Scott Michelfdc40a02009-02-17 22:15:04 +00006278
Chris Lattner12d83032006-03-05 05:30:57 +00006279 // copysign(x, fp_extend(y)) -> copysign(x, y)
6280 // copysign(x, fp_round(y)) -> copysign(x, y)
6281 if (N1.getOpcode() == ISD::FP_EXTEND || N1.getOpcode() == ISD::FP_ROUND)
Bill Wendling0225a1d2009-01-30 23:15:49 +00006282 return DAG.getNode(ISD::FCOPYSIGN, N->getDebugLoc(), VT,
6283 N0, N1.getOperand(0));
Scott Michelfdc40a02009-02-17 22:15:04 +00006284
Dan Gohman475871a2008-07-27 21:46:04 +00006285 return SDValue();
Chris Lattner12d83032006-03-05 05:30:57 +00006286}
6287
Dan Gohman475871a2008-07-27 21:46:04 +00006288SDValue DAGCombiner::visitSINT_TO_FP(SDNode *N) {
6289 SDValue N0 = N->getOperand(0);
Nate Begeman646d7e22005-09-02 21:18:40 +00006290 ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0);
Owen Andersone50ed302009-08-10 22:56:29 +00006291 EVT VT = N->getValueType(0);
6292 EVT OpVT = N0.getValueType();
Chris Lattnercda88752008-06-26 00:16:49 +00006293
Nate Begeman1d4d4142005-09-01 00:19:25 +00006294 // fold (sint_to_fp c1) -> c1fp
Ulrich Weigande669c932012-10-29 18:35:49 +00006295 if (N0C &&
Stuart Hastings7e334182011-03-02 19:36:30 +00006296 // ...but only if the target supports immediate floating-point values
Eli Friedman50185242011-11-12 00:35:34 +00006297 (!LegalOperations ||
Evan Cheng9568e5c2011-06-21 06:01:08 +00006298 TLI.isOperationLegalOrCustom(llvm::ISD::ConstantFP, VT)))
Bill Wendling0225a1d2009-01-30 23:15:49 +00006299 return DAG.getNode(ISD::SINT_TO_FP, N->getDebugLoc(), VT, N0);
Scott Michelfdc40a02009-02-17 22:15:04 +00006300
Chris Lattnercda88752008-06-26 00:16:49 +00006301 // If the input is a legal type, and SINT_TO_FP is not legal on this target,
6302 // but UINT_TO_FP is legal on this target, try to convert.
Dan Gohmanf560ffa2009-01-28 17:46:25 +00006303 if (!TLI.isOperationLegalOrCustom(ISD::SINT_TO_FP, OpVT) &&
6304 TLI.isOperationLegalOrCustom(ISD::UINT_TO_FP, OpVT)) {
Scott Michelfdc40a02009-02-17 22:15:04 +00006305 // If the sign bit is known to be zero, we can change this to UINT_TO_FP.
Chris Lattnercda88752008-06-26 00:16:49 +00006306 if (DAG.SignBitIsZero(N0))
Bill Wendling0225a1d2009-01-30 23:15:49 +00006307 return DAG.getNode(ISD::UINT_TO_FP, N->getDebugLoc(), VT, N0);
Chris Lattnercda88752008-06-26 00:16:49 +00006308 }
Bill Wendling0225a1d2009-01-30 23:15:49 +00006309
Nadav Rotemed1a3352012-07-23 07:59:50 +00006310 // The next optimizations are desireable only if SELECT_CC can be lowered.
6311 // Check against MVT::Other for SELECT_CC, which is a workaround for targets
6312 // having to say they don't support SELECT_CC on every type the DAG knows
6313 // about, since there is no way to mark an opcode illegal at all value types
6314 // (See also visitSELECT)
6315 if (TLI.isOperationLegalOrCustom(ISD::SELECT_CC, MVT::Other)) {
6316 // fold (sint_to_fp (setcc x, y, cc)) -> (select_cc x, y, -1.0, 0.0,, cc)
6317 if (N0.getOpcode() == ISD::SETCC && N0.getValueType() == MVT::i1 &&
6318 !VT.isVector() &&
6319 (!LegalOperations ||
6320 TLI.isOperationLegalOrCustom(llvm::ISD::ConstantFP, VT))) {
6321 SDValue Ops[] =
6322 { N0.getOperand(0), N0.getOperand(1),
6323 DAG.getConstantFP(-1.0, VT) , DAG.getConstantFP(0.0, VT),
6324 N0.getOperand(2) };
6325 return DAG.getNode(ISD::SELECT_CC, N->getDebugLoc(), VT, Ops, 5);
6326 }
Owen Andersond9bf71f2012-07-09 20:31:12 +00006327
Nadav Rotemed1a3352012-07-23 07:59:50 +00006328 // fold (sint_to_fp (zext (setcc x, y, cc))) ->
6329 // (select_cc x, y, 1.0, 0.0,, cc)
6330 if (N0.getOpcode() == ISD::ZERO_EXTEND &&
6331 N0.getOperand(0).getOpcode() == ISD::SETCC &&!VT.isVector() &&
6332 (!LegalOperations ||
6333 TLI.isOperationLegalOrCustom(llvm::ISD::ConstantFP, VT))) {
6334 SDValue Ops[] =
6335 { N0.getOperand(0).getOperand(0), N0.getOperand(0).getOperand(1),
6336 DAG.getConstantFP(1.0, VT) , DAG.getConstantFP(0.0, VT),
6337 N0.getOperand(0).getOperand(2) };
6338 return DAG.getNode(ISD::SELECT_CC, N->getDebugLoc(), VT, Ops, 5);
6339 }
Owen Andersond9bf71f2012-07-09 20:31:12 +00006340 }
6341
Dan Gohman475871a2008-07-27 21:46:04 +00006342 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00006343}
6344
Dan Gohman475871a2008-07-27 21:46:04 +00006345SDValue DAGCombiner::visitUINT_TO_FP(SDNode *N) {
6346 SDValue N0 = N->getOperand(0);
Nate Begeman646d7e22005-09-02 21:18:40 +00006347 ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0);
Owen Andersone50ed302009-08-10 22:56:29 +00006348 EVT VT = N->getValueType(0);
6349 EVT OpVT = N0.getValueType();
Nate Begemana148d982006-01-18 22:35:16 +00006350
Nate Begeman1d4d4142005-09-01 00:19:25 +00006351 // fold (uint_to_fp c1) -> c1fp
Ulrich Weigande669c932012-10-29 18:35:49 +00006352 if (N0C &&
Stuart Hastings7e334182011-03-02 19:36:30 +00006353 // ...but only if the target supports immediate floating-point values
Eli Friedman50185242011-11-12 00:35:34 +00006354 (!LegalOperations ||
Evan Cheng9568e5c2011-06-21 06:01:08 +00006355 TLI.isOperationLegalOrCustom(llvm::ISD::ConstantFP, VT)))
Bill Wendling0225a1d2009-01-30 23:15:49 +00006356 return DAG.getNode(ISD::UINT_TO_FP, N->getDebugLoc(), VT, N0);
Scott Michelfdc40a02009-02-17 22:15:04 +00006357
Chris Lattnercda88752008-06-26 00:16:49 +00006358 // If the input is a legal type, and UINT_TO_FP is not legal on this target,
6359 // but SINT_TO_FP is legal on this target, try to convert.
Dan Gohmanf560ffa2009-01-28 17:46:25 +00006360 if (!TLI.isOperationLegalOrCustom(ISD::UINT_TO_FP, OpVT) &&
6361 TLI.isOperationLegalOrCustom(ISD::SINT_TO_FP, OpVT)) {
Scott Michelfdc40a02009-02-17 22:15:04 +00006362 // If the sign bit is known to be zero, we can change this to SINT_TO_FP.
Chris Lattnercda88752008-06-26 00:16:49 +00006363 if (DAG.SignBitIsZero(N0))
Bill Wendling0225a1d2009-01-30 23:15:49 +00006364 return DAG.getNode(ISD::SINT_TO_FP, N->getDebugLoc(), VT, N0);
Chris Lattnercda88752008-06-26 00:16:49 +00006365 }
Scott Michelfdc40a02009-02-17 22:15:04 +00006366
Nadav Rotemed1a3352012-07-23 07:59:50 +00006367 // The next optimizations are desireable only if SELECT_CC can be lowered.
6368 // Check against MVT::Other for SELECT_CC, which is a workaround for targets
6369 // having to say they don't support SELECT_CC on every type the DAG knows
6370 // about, since there is no way to mark an opcode illegal at all value types
6371 // (See also visitSELECT)
6372 if (TLI.isOperationLegalOrCustom(ISD::SELECT_CC, MVT::Other)) {
6373 // fold (uint_to_fp (setcc x, y, cc)) -> (select_cc x, y, -1.0, 0.0,, cc)
Owen Andersond9bf71f2012-07-09 20:31:12 +00006374
Nadav Rotemed1a3352012-07-23 07:59:50 +00006375 if (N0.getOpcode() == ISD::SETCC && !VT.isVector() &&
6376 (!LegalOperations ||
6377 TLI.isOperationLegalOrCustom(llvm::ISD::ConstantFP, VT))) {
6378 SDValue Ops[] =
6379 { N0.getOperand(0), N0.getOperand(1),
6380 DAG.getConstantFP(1.0, VT), DAG.getConstantFP(0.0, VT),
6381 N0.getOperand(2) };
6382 return DAG.getNode(ISD::SELECT_CC, N->getDebugLoc(), VT, Ops, 5);
6383 }
6384 }
Owen Andersond9bf71f2012-07-09 20:31:12 +00006385
Dan Gohman475871a2008-07-27 21:46:04 +00006386 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00006387}
6388
Dan Gohman475871a2008-07-27 21:46:04 +00006389SDValue DAGCombiner::visitFP_TO_SINT(SDNode *N) {
6390 SDValue N0 = N->getOperand(0);
Nate Begemana148d982006-01-18 22:35:16 +00006391 ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(N0);
Owen Andersone50ed302009-08-10 22:56:29 +00006392 EVT VT = N->getValueType(0);
Scott Michelfdc40a02009-02-17 22:15:04 +00006393
Nate Begeman1d4d4142005-09-01 00:19:25 +00006394 // fold (fp_to_sint c1fp) -> c1
Nate Begeman646d7e22005-09-02 21:18:40 +00006395 if (N0CFP)
Bill Wendling0225a1d2009-01-30 23:15:49 +00006396 return DAG.getNode(ISD::FP_TO_SINT, N->getDebugLoc(), VT, N0);
6397
Dan Gohman475871a2008-07-27 21:46:04 +00006398 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00006399}
6400
Dan Gohman475871a2008-07-27 21:46:04 +00006401SDValue DAGCombiner::visitFP_TO_UINT(SDNode *N) {
6402 SDValue N0 = N->getOperand(0);
Nate Begemana148d982006-01-18 22:35:16 +00006403 ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(N0);
Owen Andersone50ed302009-08-10 22:56:29 +00006404 EVT VT = N->getValueType(0);
Scott Michelfdc40a02009-02-17 22:15:04 +00006405
Nate Begeman1d4d4142005-09-01 00:19:25 +00006406 // fold (fp_to_uint c1fp) -> c1
Ulrich Weigande669c932012-10-29 18:35:49 +00006407 if (N0CFP)
Bill Wendling0225a1d2009-01-30 23:15:49 +00006408 return DAG.getNode(ISD::FP_TO_UINT, N->getDebugLoc(), VT, N0);
6409
Dan Gohman475871a2008-07-27 21:46:04 +00006410 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00006411}
6412
Dan Gohman475871a2008-07-27 21:46:04 +00006413SDValue DAGCombiner::visitFP_ROUND(SDNode *N) {
6414 SDValue N0 = N->getOperand(0);
6415 SDValue N1 = N->getOperand(1);
Nate Begemana148d982006-01-18 22:35:16 +00006416 ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(N0);
Owen Andersone50ed302009-08-10 22:56:29 +00006417 EVT VT = N->getValueType(0);
Scott Michelfdc40a02009-02-17 22:15:04 +00006418
Nate Begeman1d4d4142005-09-01 00:19:25 +00006419 // fold (fp_round c1fp) -> c1fp
Ulrich Weigande669c932012-10-29 18:35:49 +00006420 if (N0CFP)
Bill Wendling0225a1d2009-01-30 23:15:49 +00006421 return DAG.getNode(ISD::FP_ROUND, N->getDebugLoc(), VT, N0, N1);
Scott Michelfdc40a02009-02-17 22:15:04 +00006422
Chris Lattner79dbea52006-03-13 06:26:26 +00006423 // fold (fp_round (fp_extend x)) -> x
6424 if (N0.getOpcode() == ISD::FP_EXTEND && VT == N0.getOperand(0).getValueType())
6425 return N0.getOperand(0);
Scott Michelfdc40a02009-02-17 22:15:04 +00006426
Chris Lattner0aa5e6f2008-01-24 06:45:35 +00006427 // fold (fp_round (fp_round x)) -> (fp_round x)
6428 if (N0.getOpcode() == ISD::FP_ROUND) {
6429 // This is a value preserving truncation if both round's are.
6430 bool IsTrunc = N->getConstantOperandVal(1) == 1 &&
Gabor Greifba36cb52008-08-28 21:40:38 +00006431 N0.getNode()->getConstantOperandVal(1) == 1;
Bill Wendling0225a1d2009-01-30 23:15:49 +00006432 return DAG.getNode(ISD::FP_ROUND, N->getDebugLoc(), VT, N0.getOperand(0),
Chris Lattner0aa5e6f2008-01-24 06:45:35 +00006433 DAG.getIntPtrConstant(IsTrunc));
6434 }
Scott Michelfdc40a02009-02-17 22:15:04 +00006435
Chris Lattner79dbea52006-03-13 06:26:26 +00006436 // fold (fp_round (copysign X, Y)) -> (copysign (fp_round X), Y)
Gabor Greifba36cb52008-08-28 21:40:38 +00006437 if (N0.getOpcode() == ISD::FCOPYSIGN && N0.getNode()->hasOneUse()) {
Bill Wendling0225a1d2009-01-30 23:15:49 +00006438 SDValue Tmp = DAG.getNode(ISD::FP_ROUND, N0.getDebugLoc(), VT,
6439 N0.getOperand(0), N1);
Gabor Greifba36cb52008-08-28 21:40:38 +00006440 AddToWorkList(Tmp.getNode());
Bill Wendling0225a1d2009-01-30 23:15:49 +00006441 return DAG.getNode(ISD::FCOPYSIGN, N->getDebugLoc(), VT,
6442 Tmp, N0.getOperand(1));
Chris Lattner79dbea52006-03-13 06:26:26 +00006443 }
Scott Michelfdc40a02009-02-17 22:15:04 +00006444
Dan Gohman475871a2008-07-27 21:46:04 +00006445 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00006446}
6447
Dan Gohman475871a2008-07-27 21:46:04 +00006448SDValue DAGCombiner::visitFP_ROUND_INREG(SDNode *N) {
6449 SDValue N0 = N->getOperand(0);
Owen Andersone50ed302009-08-10 22:56:29 +00006450 EVT VT = N->getValueType(0);
6451 EVT EVT = cast<VTSDNode>(N->getOperand(1))->getVT();
Nate Begeman646d7e22005-09-02 21:18:40 +00006452 ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(N0);
Scott Michelfdc40a02009-02-17 22:15:04 +00006453
Nate Begeman1d4d4142005-09-01 00:19:25 +00006454 // fold (fp_round_inreg c1fp) -> c1fp
Chris Lattner2392ae72010-04-15 04:48:01 +00006455 if (N0CFP && isTypeLegal(EVT)) {
Dan Gohman4fbd7962008-09-12 18:08:03 +00006456 SDValue Round = DAG.getConstantFP(*N0CFP->getConstantFPValue(), EVT);
Bill Wendling0225a1d2009-01-30 23:15:49 +00006457 return DAG.getNode(ISD::FP_EXTEND, N->getDebugLoc(), VT, Round);
Nate Begeman1d4d4142005-09-01 00:19:25 +00006458 }
Bill Wendling0225a1d2009-01-30 23:15:49 +00006459
Dan Gohman475871a2008-07-27 21:46:04 +00006460 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00006461}
6462
Dan Gohman475871a2008-07-27 21:46:04 +00006463SDValue DAGCombiner::visitFP_EXTEND(SDNode *N) {
6464 SDValue N0 = N->getOperand(0);
Nate Begemana148d982006-01-18 22:35:16 +00006465 ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(N0);
Owen Andersone50ed302009-08-10 22:56:29 +00006466 EVT VT = N->getValueType(0);
Scott Michelfdc40a02009-02-17 22:15:04 +00006467
Chris Lattner5938bef2007-12-29 06:55:23 +00006468 // If this is fp_round(fpextend), don't fold it, allow ourselves to be folded.
Scott Michelfdc40a02009-02-17 22:15:04 +00006469 if (N->hasOneUse() &&
Dan Gohmane7852d02009-01-26 04:35:06 +00006470 N->use_begin()->getOpcode() == ISD::FP_ROUND)
Dan Gohman475871a2008-07-27 21:46:04 +00006471 return SDValue();
Chris Lattner0bd48932008-01-17 07:00:52 +00006472
Nate Begeman1d4d4142005-09-01 00:19:25 +00006473 // fold (fp_extend c1fp) -> c1fp
Ulrich Weigande669c932012-10-29 18:35:49 +00006474 if (N0CFP)
Bill Wendling0225a1d2009-01-30 23:15:49 +00006475 return DAG.getNode(ISD::FP_EXTEND, N->getDebugLoc(), VT, N0);
Chris Lattner0bd48932008-01-17 07:00:52 +00006476
6477 // Turn fp_extend(fp_round(X, 1)) -> x since the fp_round doesn't affect the
6478 // value of X.
Gabor Greif12632d22008-08-30 19:29:20 +00006479 if (N0.getOpcode() == ISD::FP_ROUND
6480 && N0.getNode()->getConstantOperandVal(1) == 1) {
Dan Gohman475871a2008-07-27 21:46:04 +00006481 SDValue In = N0.getOperand(0);
Chris Lattner0bd48932008-01-17 07:00:52 +00006482 if (In.getValueType() == VT) return In;
Duncan Sands8e4eb092008-06-08 20:54:56 +00006483 if (VT.bitsLT(In.getValueType()))
Bill Wendling0225a1d2009-01-30 23:15:49 +00006484 return DAG.getNode(ISD::FP_ROUND, N->getDebugLoc(), VT,
6485 In, N0.getOperand(1));
6486 return DAG.getNode(ISD::FP_EXTEND, N->getDebugLoc(), VT, In);
Chris Lattner0bd48932008-01-17 07:00:52 +00006487 }
Scott Michelfdc40a02009-02-17 22:15:04 +00006488
Chris Lattner0bd48932008-01-17 07:00:52 +00006489 // fold (fpext (load x)) -> (fpext (fptrunc (extload x)))
Gabor Greifba36cb52008-08-28 21:40:38 +00006490 if (ISD::isNON_EXTLoad(N0.getNode()) && N0.hasOneUse() &&
Duncan Sands25cf2272008-11-24 14:53:14 +00006491 ((!LegalOperations && !cast<LoadSDNode>(N0)->isVolatile()) ||
Evan Cheng03294662008-10-14 21:26:46 +00006492 TLI.isLoadExtLegal(ISD::EXTLOAD, N0.getValueType()))) {
Evan Cheng466685d2006-10-09 20:57:25 +00006493 LoadSDNode *LN0 = cast<LoadSDNode>(N0);
Stuart Hastingsa9011292011-02-16 16:23:55 +00006494 SDValue ExtLoad = DAG.getExtLoad(ISD::EXTLOAD, N->getDebugLoc(), VT,
Bill Wendling0225a1d2009-01-30 23:15:49 +00006495 LN0->getChain(),
Chris Lattner3d6ccfb2010-09-21 17:04:51 +00006496 LN0->getBasePtr(), LN0->getPointerInfo(),
Duncan Sands25cf2272008-11-24 14:53:14 +00006497 N0.getValueType(),
David Greene1e559442010-02-15 17:00:31 +00006498 LN0->isVolatile(), LN0->isNonTemporal(),
6499 LN0->getAlignment());
Chris Lattnere564dbb2006-05-05 21:34:35 +00006500 CombineTo(N, ExtLoad);
Bill Wendling0225a1d2009-01-30 23:15:49 +00006501 CombineTo(N0.getNode(),
6502 DAG.getNode(ISD::FP_ROUND, N0.getDebugLoc(),
6503 N0.getValueType(), ExtLoad, DAG.getIntPtrConstant(1)),
Chris Lattnere564dbb2006-05-05 21:34:35 +00006504 ExtLoad.getValue(1));
Dan Gohman475871a2008-07-27 21:46:04 +00006505 return SDValue(N, 0); // Return N so it doesn't get rechecked!
Chris Lattnere564dbb2006-05-05 21:34:35 +00006506 }
Duncan Sandsd4b9c172008-06-13 19:07:40 +00006507
Dan Gohman475871a2008-07-27 21:46:04 +00006508 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00006509}
6510
Dan Gohman475871a2008-07-27 21:46:04 +00006511SDValue DAGCombiner::visitFNEG(SDNode *N) {
6512 SDValue N0 = N->getOperand(0);
Anton Korobeynikov2bcf60a2009-10-20 21:37:45 +00006513 EVT VT = N->getValueType(0);
Nate Begemana148d982006-01-18 22:35:16 +00006514
Craig Topperdd201ff2012-09-11 01:45:21 +00006515 if (VT.isVector()) {
6516 SDValue FoldedVOp = SimplifyVUnaryOp(N);
6517 if (FoldedVOp.getNode()) return FoldedVOp;
Craig Topper956342b2012-09-09 22:58:45 +00006518 }
6519
Owen Andersonafd3d562012-03-06 00:29:31 +00006520 if (isNegatibleForFree(N0, LegalOperations, DAG.getTargetLoweringInfo(),
6521 &DAG.getTarget().Options))
Duncan Sands25cf2272008-11-24 14:53:14 +00006522 return GetNegatedExpression(N0, DAG, LegalOperations);
Dan Gohman23ff1822007-07-02 15:48:56 +00006523
Chris Lattner3bd39d42008-01-27 17:42:27 +00006524 // Transform fneg(bitconvert(x)) -> bitconvert(x^sign) to avoid loading
6525 // constant pool values.
Owen Anderson29f60f32012-04-02 22:10:29 +00006526 if (!TLI.isFNegFree(VT) && N0.getOpcode() == ISD::BITCAST &&
Anton Korobeynikov2bcf60a2009-10-20 21:37:45 +00006527 !VT.isVector() &&
6528 N0.getNode()->hasOneUse() &&
6529 N0.getOperand(0).getValueType().isInteger()) {
Dan Gohman475871a2008-07-27 21:46:04 +00006530 SDValue Int = N0.getOperand(0);
Owen Andersone50ed302009-08-10 22:56:29 +00006531 EVT IntVT = Int.getValueType();
Duncan Sands83ec4b62008-06-06 12:08:01 +00006532 if (IntVT.isInteger() && !IntVT.isVector()) {
Duncan Sandsb0d5cdd2009-02-01 18:06:53 +00006533 Int = DAG.getNode(ISD::XOR, N0.getDebugLoc(), IntVT, Int,
6534 DAG.getConstant(APInt::getSignBit(IntVT.getSizeInBits()), IntVT));
Gabor Greifba36cb52008-08-28 21:40:38 +00006535 AddToWorkList(Int.getNode());
Wesley Peckbf17cfa2010-11-23 03:31:01 +00006536 return DAG.getNode(ISD::BITCAST, N->getDebugLoc(),
Anton Korobeynikov2bcf60a2009-10-20 21:37:45 +00006537 VT, Int);
Chris Lattner3bd39d42008-01-27 17:42:27 +00006538 }
6539 }
Scott Michelfdc40a02009-02-17 22:15:04 +00006540
Owen Anderson58d57292012-09-01 06:04:27 +00006541 // (fneg (fmul c, x)) -> (fmul -c, x)
6542 if (N0.getOpcode() == ISD::FMUL) {
6543 ConstantFPSDNode *CFP1 = dyn_cast<ConstantFPSDNode>(N0.getOperand(1));
6544 if (CFP1) {
6545 return DAG.getNode(ISD::FMUL, N->getDebugLoc(), VT,
6546 N0.getOperand(0),
6547 DAG.getNode(ISD::FNEG, N->getDebugLoc(), VT,
6548 N0.getOperand(1)));
6549 }
6550 }
6551
Dan Gohman475871a2008-07-27 21:46:04 +00006552 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00006553}
6554
Owen Anderson7c626d32012-08-13 23:32:49 +00006555SDValue DAGCombiner::visitFCEIL(SDNode *N) {
6556 SDValue N0 = N->getOperand(0);
6557 ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(N0);
6558 EVT VT = N->getValueType(0);
6559
6560 // fold (fceil c1) -> fceil(c1)
Ulrich Weigande669c932012-10-29 18:35:49 +00006561 if (N0CFP)
Owen Anderson7c626d32012-08-13 23:32:49 +00006562 return DAG.getNode(ISD::FCEIL, N->getDebugLoc(), VT, N0);
6563
6564 return SDValue();
6565}
6566
6567SDValue DAGCombiner::visitFTRUNC(SDNode *N) {
6568 SDValue N0 = N->getOperand(0);
6569 ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(N0);
6570 EVT VT = N->getValueType(0);
6571
6572 // fold (ftrunc c1) -> ftrunc(c1)
Ulrich Weigande669c932012-10-29 18:35:49 +00006573 if (N0CFP)
Owen Anderson7c626d32012-08-13 23:32:49 +00006574 return DAG.getNode(ISD::FTRUNC, N->getDebugLoc(), VT, N0);
6575
6576 return SDValue();
6577}
6578
6579SDValue DAGCombiner::visitFFLOOR(SDNode *N) {
6580 SDValue N0 = N->getOperand(0);
6581 ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(N0);
6582 EVT VT = N->getValueType(0);
6583
6584 // fold (ffloor c1) -> ffloor(c1)
Ulrich Weigande669c932012-10-29 18:35:49 +00006585 if (N0CFP)
Owen Anderson7c626d32012-08-13 23:32:49 +00006586 return DAG.getNode(ISD::FFLOOR, N->getDebugLoc(), VT, N0);
6587
6588 return SDValue();
6589}
6590
Dan Gohman475871a2008-07-27 21:46:04 +00006591SDValue DAGCombiner::visitFABS(SDNode *N) {
6592 SDValue N0 = N->getOperand(0);
Nate Begemana148d982006-01-18 22:35:16 +00006593 ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(N0);
Owen Andersone50ed302009-08-10 22:56:29 +00006594 EVT VT = N->getValueType(0);
Scott Michelfdc40a02009-02-17 22:15:04 +00006595
Craig Topperdd201ff2012-09-11 01:45:21 +00006596 if (VT.isVector()) {
6597 SDValue FoldedVOp = SimplifyVUnaryOp(N);
6598 if (FoldedVOp.getNode()) return FoldedVOp;
6599 }
6600
Nate Begeman1d4d4142005-09-01 00:19:25 +00006601 // fold (fabs c1) -> fabs(c1)
Ulrich Weigande669c932012-10-29 18:35:49 +00006602 if (N0CFP)
Bill Wendlingc0debad2009-01-30 23:27:35 +00006603 return DAG.getNode(ISD::FABS, N->getDebugLoc(), VT, N0);
Nate Begeman1d4d4142005-09-01 00:19:25 +00006604 // fold (fabs (fabs x)) -> (fabs x)
Chris Lattner12d83032006-03-05 05:30:57 +00006605 if (N0.getOpcode() == ISD::FABS)
Nate Begeman83e75ec2005-09-06 04:43:02 +00006606 return N->getOperand(0);
Nate Begeman1d4d4142005-09-01 00:19:25 +00006607 // fold (fabs (fneg x)) -> (fabs x)
Chris Lattner12d83032006-03-05 05:30:57 +00006608 // fold (fabs (fcopysign x, y)) -> (fabs x)
6609 if (N0.getOpcode() == ISD::FNEG || N0.getOpcode() == ISD::FCOPYSIGN)
Bill Wendlingc0debad2009-01-30 23:27:35 +00006610 return DAG.getNode(ISD::FABS, N->getDebugLoc(), VT, N0.getOperand(0));
Scott Michelfdc40a02009-02-17 22:15:04 +00006611
Chris Lattner3bd39d42008-01-27 17:42:27 +00006612 // Transform fabs(bitconvert(x)) -> bitconvert(x&~sign) to avoid loading
6613 // constant pool values.
Owen Anderson29f60f32012-04-02 22:10:29 +00006614 if (!TLI.isFAbsFree(VT) &&
6615 N0.getOpcode() == ISD::BITCAST && N0.getNode()->hasOneUse() &&
Duncan Sands83ec4b62008-06-06 12:08:01 +00006616 N0.getOperand(0).getValueType().isInteger() &&
6617 !N0.getOperand(0).getValueType().isVector()) {
Dan Gohman475871a2008-07-27 21:46:04 +00006618 SDValue Int = N0.getOperand(0);
Owen Andersone50ed302009-08-10 22:56:29 +00006619 EVT IntVT = Int.getValueType();
Duncan Sands83ec4b62008-06-06 12:08:01 +00006620 if (IntVT.isInteger() && !IntVT.isVector()) {
Scott Michelfdc40a02009-02-17 22:15:04 +00006621 Int = DAG.getNode(ISD::AND, N0.getDebugLoc(), IntVT, Int,
Duncan Sandsb0d5cdd2009-02-01 18:06:53 +00006622 DAG.getConstant(~APInt::getSignBit(IntVT.getSizeInBits()), IntVT));
Gabor Greifba36cb52008-08-28 21:40:38 +00006623 AddToWorkList(Int.getNode());
Wesley Peckbf17cfa2010-11-23 03:31:01 +00006624 return DAG.getNode(ISD::BITCAST, N->getDebugLoc(),
Bill Wendlingc0debad2009-01-30 23:27:35 +00006625 N->getValueType(0), Int);
Chris Lattner3bd39d42008-01-27 17:42:27 +00006626 }
6627 }
Scott Michelfdc40a02009-02-17 22:15:04 +00006628
Dan Gohman475871a2008-07-27 21:46:04 +00006629 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00006630}
6631
Dan Gohman475871a2008-07-27 21:46:04 +00006632SDValue DAGCombiner::visitBRCOND(SDNode *N) {
6633 SDValue Chain = N->getOperand(0);
6634 SDValue N1 = N->getOperand(1);
6635 SDValue N2 = N->getOperand(2);
Scott Michelfdc40a02009-02-17 22:15:04 +00006636
Dan Gohmane0f06c72009-11-17 00:47:23 +00006637 // If N is a constant we could fold this into a fallthrough or unconditional
6638 // branch. However that doesn't happen very often in normal code, because
6639 // Instcombine/SimplifyCFG should have handled the available opportunities.
6640 // If we did this folding here, it would be necessary to update the
6641 // MachineBasicBlock CFG, which is awkward.
6642
Nate Begeman750ac1b2006-02-01 07:19:44 +00006643 // fold a brcond with a setcc condition into a BR_CC node if BR_CC is legal
6644 // on the target.
Scott Michelfdc40a02009-02-17 22:15:04 +00006645 if (N1.getOpcode() == ISD::SETCC &&
Owen Anderson825b72b2009-08-11 20:47:22 +00006646 TLI.isOperationLegalOrCustom(ISD::BR_CC, MVT::Other)) {
6647 return DAG.getNode(ISD::BR_CC, N->getDebugLoc(), MVT::Other,
Bill Wendlingc0debad2009-01-30 23:27:35 +00006648 Chain, N1.getOperand(2),
Nate Begeman750ac1b2006-02-01 07:19:44 +00006649 N1.getOperand(0), N1.getOperand(1), N2);
6650 }
Bill Wendlingc0debad2009-01-30 23:27:35 +00006651
Evan Cheng2a135ae2010-10-04 22:41:01 +00006652 if ((N1.hasOneUse() && N1.getOpcode() == ISD::SRL) ||
6653 ((N1.getOpcode() == ISD::TRUNCATE && N1.hasOneUse()) &&
6654 (N1.getOperand(0).hasOneUse() &&
6655 N1.getOperand(0).getOpcode() == ISD::SRL))) {
6656 SDNode *Trunc = 0;
6657 if (N1.getOpcode() == ISD::TRUNCATE) {
6658 // Look pass the truncate.
6659 Trunc = N1.getNode();
6660 N1 = N1.getOperand(0);
6661 }
Evan Chengd40d03e2010-01-06 19:38:29 +00006662
Bill Wendlinga02a3dd2009-03-26 06:14:09 +00006663 // Match this pattern so that we can generate simpler code:
6664 //
6665 // %a = ...
6666 // %b = and i32 %a, 2
6667 // %c = srl i32 %b, 1
6668 // brcond i32 %c ...
6669 //
6670 // into
Wesley Peckbf17cfa2010-11-23 03:31:01 +00006671 //
Bill Wendlinga02a3dd2009-03-26 06:14:09 +00006672 // %a = ...
Evan Chengd40d03e2010-01-06 19:38:29 +00006673 // %b = and i32 %a, 2
Bill Wendlinga02a3dd2009-03-26 06:14:09 +00006674 // %c = setcc eq %b, 0
6675 // brcond %c ...
6676 //
6677 // This applies only when the AND constant value has one bit set and the
6678 // SRL constant is equal to the log2 of the AND constant. The back-end is
6679 // smart enough to convert the result into a TEST/JMP sequence.
6680 SDValue Op0 = N1.getOperand(0);
6681 SDValue Op1 = N1.getOperand(1);
6682
6683 if (Op0.getOpcode() == ISD::AND &&
Bill Wendlinga02a3dd2009-03-26 06:14:09 +00006684 Op1.getOpcode() == ISD::Constant) {
Bill Wendlinga02a3dd2009-03-26 06:14:09 +00006685 SDValue AndOp1 = Op0.getOperand(1);
6686
6687 if (AndOp1.getOpcode() == ISD::Constant) {
6688 const APInt &AndConst = cast<ConstantSDNode>(AndOp1)->getAPIntValue();
6689
6690 if (AndConst.isPowerOf2() &&
6691 cast<ConstantSDNode>(Op1)->getAPIntValue()==AndConst.logBase2()) {
6692 SDValue SetCC =
6693 DAG.getSetCC(N->getDebugLoc(),
6694 TLI.getSetCCResultType(Op0.getValueType()),
6695 Op0, DAG.getConstant(0, Op0.getValueType()),
6696 ISD::SETNE);
6697
Evan Chengd40d03e2010-01-06 19:38:29 +00006698 SDValue NewBRCond = DAG.getNode(ISD::BRCOND, N->getDebugLoc(),
6699 MVT::Other, Chain, SetCC, N2);
6700 // Don't add the new BRCond into the worklist or else SimplifySelectCC
6701 // will convert it back to (X & C1) >> C2.
6702 CombineTo(N, NewBRCond, false);
6703 // Truncate is dead.
6704 if (Trunc) {
6705 removeFromWorkList(Trunc);
6706 DAG.DeleteNode(Trunc);
6707 }
Bill Wendlinga02a3dd2009-03-26 06:14:09 +00006708 // Replace the uses of SRL with SETCC
Evan Cheng2c755ba2010-02-27 07:36:59 +00006709 WorkListRemover DeadNodes(*this);
Jakob Stoklund Olesenbc7d4482012-04-20 22:08:46 +00006710 DAG.ReplaceAllUsesOfValueWith(N1, SetCC);
Bill Wendlinga02a3dd2009-03-26 06:14:09 +00006711 removeFromWorkList(N1.getNode());
6712 DAG.DeleteNode(N1.getNode());
Evan Chengd40d03e2010-01-06 19:38:29 +00006713 return SDValue(N, 0); // Return N so it doesn't get rechecked!
Bill Wendlinga02a3dd2009-03-26 06:14:09 +00006714 }
6715 }
6716 }
Evan Cheng2a135ae2010-10-04 22:41:01 +00006717
6718 if (Trunc)
6719 // Restore N1 if the above transformation doesn't match.
6720 N1 = N->getOperand(1);
Bill Wendlinga02a3dd2009-03-26 06:14:09 +00006721 }
Wesley Peckbf17cfa2010-11-23 03:31:01 +00006722
Evan Cheng2c755ba2010-02-27 07:36:59 +00006723 // Transform br(xor(x, y)) -> br(x != y)
6724 // Transform br(xor(xor(x,y), 1)) -> br (x == y)
6725 if (N1.hasOneUse() && N1.getOpcode() == ISD::XOR) {
6726 SDNode *TheXor = N1.getNode();
6727 SDValue Op0 = TheXor->getOperand(0);
6728 SDValue Op1 = TheXor->getOperand(1);
6729 if (Op0.getOpcode() == Op1.getOpcode()) {
6730 // Avoid missing important xor optimizations.
6731 SDValue Tmp = visitXOR(TheXor);
Bill Wendling86c5abb2010-04-20 01:25:01 +00006732 if (Tmp.getNode() && Tmp.getNode() != TheXor) {
Evan Cheng2c755ba2010-02-27 07:36:59 +00006733 DEBUG(dbgs() << "\nReplacing.8 ";
6734 TheXor->dump(&DAG);
6735 dbgs() << "\nWith: ";
6736 Tmp.getNode()->dump(&DAG);
6737 dbgs() << '\n');
6738 WorkListRemover DeadNodes(*this);
Jakob Stoklund Olesenbc7d4482012-04-20 22:08:46 +00006739 DAG.ReplaceAllUsesOfValueWith(N1, Tmp);
Evan Cheng2c755ba2010-02-27 07:36:59 +00006740 removeFromWorkList(TheXor);
6741 DAG.DeleteNode(TheXor);
6742 return DAG.getNode(ISD::BRCOND, N->getDebugLoc(),
6743 MVT::Other, Chain, Tmp, N2);
6744 }
6745 }
6746
6747 if (Op0.getOpcode() != ISD::SETCC && Op1.getOpcode() != ISD::SETCC) {
6748 bool Equal = false;
6749 if (ConstantSDNode *RHSCI = dyn_cast<ConstantSDNode>(Op0))
6750 if (RHSCI->getAPIntValue() == 1 && Op0.hasOneUse() &&
6751 Op0.getOpcode() == ISD::XOR) {
6752 TheXor = Op0.getNode();
6753 Equal = true;
6754 }
6755
Evan Cheng2a135ae2010-10-04 22:41:01 +00006756 EVT SetCCVT = N1.getValueType();
Evan Cheng2c755ba2010-02-27 07:36:59 +00006757 if (LegalTypes)
6758 SetCCVT = TLI.getSetCCResultType(SetCCVT);
6759 SDValue SetCC = DAG.getSetCC(TheXor->getDebugLoc(),
6760 SetCCVT,
6761 Op0, Op1,
6762 Equal ? ISD::SETEQ : ISD::SETNE);
6763 // Replace the uses of XOR with SETCC
6764 WorkListRemover DeadNodes(*this);
Jakob Stoklund Olesenbc7d4482012-04-20 22:08:46 +00006765 DAG.ReplaceAllUsesOfValueWith(N1, SetCC);
Evan Cheng2a135ae2010-10-04 22:41:01 +00006766 removeFromWorkList(N1.getNode());
6767 DAG.DeleteNode(N1.getNode());
Evan Cheng2c755ba2010-02-27 07:36:59 +00006768 return DAG.getNode(ISD::BRCOND, N->getDebugLoc(),
6769 MVT::Other, Chain, SetCC, N2);
6770 }
6771 }
Bill Wendlinga02a3dd2009-03-26 06:14:09 +00006772
Dan Gohman475871a2008-07-27 21:46:04 +00006773 return SDValue();
Nate Begeman44728a72005-09-19 22:34:01 +00006774}
6775
Chris Lattner3ea0b472005-10-05 06:47:48 +00006776// Operand List for BR_CC: Chain, CondCC, CondLHS, CondRHS, DestBB.
6777//
Dan Gohman475871a2008-07-27 21:46:04 +00006778SDValue DAGCombiner::visitBR_CC(SDNode *N) {
Chris Lattner3ea0b472005-10-05 06:47:48 +00006779 CondCodeSDNode *CC = cast<CondCodeSDNode>(N->getOperand(1));
Dan Gohman475871a2008-07-27 21:46:04 +00006780 SDValue CondLHS = N->getOperand(2), CondRHS = N->getOperand(3);
Scott Michelfdc40a02009-02-17 22:15:04 +00006781
Dan Gohmane0f06c72009-11-17 00:47:23 +00006782 // If N is a constant we could fold this into a fallthrough or unconditional
6783 // branch. However that doesn't happen very often in normal code, because
6784 // Instcombine/SimplifyCFG should have handled the available opportunities.
6785 // If we did this folding here, it would be necessary to update the
6786 // MachineBasicBlock CFG, which is awkward.
6787
Duncan Sands8eab8a22008-06-09 11:32:28 +00006788 // Use SimplifySetCC to simplify SETCC's.
Duncan Sands5480c042009-01-01 15:52:00 +00006789 SDValue Simp = SimplifySetCC(TLI.getSetCCResultType(CondLHS.getValueType()),
Dale Johannesenff97d4f2009-02-03 00:47:48 +00006790 CondLHS, CondRHS, CC->get(), N->getDebugLoc(),
6791 false);
Gabor Greifba36cb52008-08-28 21:40:38 +00006792 if (Simp.getNode()) AddToWorkList(Simp.getNode());
Chris Lattner30f73e72006-10-14 03:52:46 +00006793
Nate Begemane17daeb2005-10-05 21:43:42 +00006794 // fold to a simpler setcc
Gabor Greifba36cb52008-08-28 21:40:38 +00006795 if (Simp.getNode() && Simp.getOpcode() == ISD::SETCC)
Owen Anderson825b72b2009-08-11 20:47:22 +00006796 return DAG.getNode(ISD::BR_CC, N->getDebugLoc(), MVT::Other,
Bill Wendlingc0debad2009-01-30 23:27:35 +00006797 N->getOperand(0), Simp.getOperand(2),
6798 Simp.getOperand(0), Simp.getOperand(1),
6799 N->getOperand(4));
6800
Dan Gohman475871a2008-07-27 21:46:04 +00006801 return SDValue();
Nate Begeman44728a72005-09-19 22:34:01 +00006802}
6803
Evan Chengc4b527a2012-01-13 01:37:24 +00006804/// canFoldInAddressingMode - Return true if 'Use' is a load or a store that
6805/// uses N as its base pointer and that N may be folded in the load / store
Evan Cheng03be3622012-03-06 23:33:32 +00006806/// addressing mode.
Evan Chengc4b527a2012-01-13 01:37:24 +00006807static bool canFoldInAddressingMode(SDNode *N, SDNode *Use,
6808 SelectionDAG &DAG,
6809 const TargetLowering &TLI) {
6810 EVT VT;
6811 if (LoadSDNode *LD = dyn_cast<LoadSDNode>(Use)) {
6812 if (LD->isIndexed() || LD->getBasePtr().getNode() != N)
6813 return false;
6814 VT = Use->getValueType(0);
6815 } else if (StoreSDNode *ST = dyn_cast<StoreSDNode>(Use)) {
6816 if (ST->isIndexed() || ST->getBasePtr().getNode() != N)
6817 return false;
6818 VT = ST->getValue().getValueType();
6819 } else
6820 return false;
6821
Nadav Rotemad6aedc2012-10-08 23:06:34 +00006822 AddrMode AM;
Evan Chengc4b527a2012-01-13 01:37:24 +00006823 if (N->getOpcode() == ISD::ADD) {
6824 ConstantSDNode *Offset = dyn_cast<ConstantSDNode>(N->getOperand(1));
6825 if (Offset)
Evan Cheng03be3622012-03-06 23:33:32 +00006826 // [reg +/- imm]
Evan Chengc4b527a2012-01-13 01:37:24 +00006827 AM.BaseOffs = Offset->getSExtValue();
6828 else
Evan Cheng03be3622012-03-06 23:33:32 +00006829 // [reg +/- reg]
6830 AM.Scale = 1;
Evan Chengc4b527a2012-01-13 01:37:24 +00006831 } else if (N->getOpcode() == ISD::SUB) {
6832 ConstantSDNode *Offset = dyn_cast<ConstantSDNode>(N->getOperand(1));
6833 if (Offset)
Evan Cheng03be3622012-03-06 23:33:32 +00006834 // [reg +/- imm]
Evan Chengc4b527a2012-01-13 01:37:24 +00006835 AM.BaseOffs = -Offset->getSExtValue();
6836 else
Evan Cheng03be3622012-03-06 23:33:32 +00006837 // [reg +/- reg]
6838 AM.Scale = 1;
Evan Chengc4b527a2012-01-13 01:37:24 +00006839 } else
6840 return false;
6841
6842 return TLI.isLegalAddressingMode(AM, VT.getTypeForEVT(*DAG.getContext()));
6843}
6844
Duncan Sandsec87aa82008-06-15 20:12:31 +00006845/// CombineToPreIndexedLoadStore - Try turning a load / store into a
6846/// pre-indexed load / store when the base pointer is an add or subtract
Chris Lattner448f2192006-11-11 00:39:41 +00006847/// and it has other uses besides the load / store. After the
6848/// transformation, the new indexed load / store has effectively folded
6849/// the add / subtract in and all of its other uses are redirected to the
6850/// new load / store.
6851bool DAGCombiner::CombineToPreIndexedLoadStore(SDNode *N) {
Eli Friedman50185242011-11-12 00:35:34 +00006852 if (Level < AfterLegalizeDAG)
Chris Lattner448f2192006-11-11 00:39:41 +00006853 return false;
6854
6855 bool isLoad = true;
Dan Gohman475871a2008-07-27 21:46:04 +00006856 SDValue Ptr;
Owen Andersone50ed302009-08-10 22:56:29 +00006857 EVT VT;
Chris Lattner448f2192006-11-11 00:39:41 +00006858 if (LoadSDNode *LD = dyn_cast<LoadSDNode>(N)) {
Chris Lattnerddf89562008-01-17 19:59:44 +00006859 if (LD->isIndexed())
Evan Chenge90460e2006-12-16 06:25:23 +00006860 return false;
Dan Gohmanb625f2f2008-01-30 00:15:11 +00006861 VT = LD->getMemoryVT();
Evan Cheng83060c52007-03-07 08:07:03 +00006862 if (!TLI.isIndexedLoadLegal(ISD::PRE_INC, VT) &&
Chris Lattner448f2192006-11-11 00:39:41 +00006863 !TLI.isIndexedLoadLegal(ISD::PRE_DEC, VT))
6864 return false;
6865 Ptr = LD->getBasePtr();
6866 } else if (StoreSDNode *ST = dyn_cast<StoreSDNode>(N)) {
Chris Lattnerddf89562008-01-17 19:59:44 +00006867 if (ST->isIndexed())
Evan Chenge90460e2006-12-16 06:25:23 +00006868 return false;
Dan Gohmanb625f2f2008-01-30 00:15:11 +00006869 VT = ST->getMemoryVT();
Chris Lattner448f2192006-11-11 00:39:41 +00006870 if (!TLI.isIndexedStoreLegal(ISD::PRE_INC, VT) &&
6871 !TLI.isIndexedStoreLegal(ISD::PRE_DEC, VT))
6872 return false;
6873 Ptr = ST->getBasePtr();
6874 isLoad = false;
Bill Wendlingc0debad2009-01-30 23:27:35 +00006875 } else {
Chris Lattner448f2192006-11-11 00:39:41 +00006876 return false;
Bill Wendlingc0debad2009-01-30 23:27:35 +00006877 }
Chris Lattner448f2192006-11-11 00:39:41 +00006878
Chris Lattner9f1794e2006-11-11 00:56:29 +00006879 // If the pointer is not an add/sub, or if it doesn't have multiple uses, bail
6880 // out. There is no reason to make this a preinc/predec.
6881 if ((Ptr.getOpcode() != ISD::ADD && Ptr.getOpcode() != ISD::SUB) ||
Gabor Greifba36cb52008-08-28 21:40:38 +00006882 Ptr.getNode()->hasOneUse())
Chris Lattner9f1794e2006-11-11 00:56:29 +00006883 return false;
Chris Lattner448f2192006-11-11 00:39:41 +00006884
Chris Lattner9f1794e2006-11-11 00:56:29 +00006885 // Ask the target to do addressing mode selection.
Dan Gohman475871a2008-07-27 21:46:04 +00006886 SDValue BasePtr;
6887 SDValue Offset;
Chris Lattner9f1794e2006-11-11 00:56:29 +00006888 ISD::MemIndexedMode AM = ISD::UNINDEXED;
6889 if (!TLI.getPreIndexedAddressParts(N, BasePtr, Offset, AM, DAG))
6890 return false;
Evan Chenga7d4a042007-05-03 23:52:19 +00006891 // Don't create a indexed load / store with zero offset.
6892 if (isa<ConstantSDNode>(Offset) &&
Dan Gohman002e5d02008-03-13 22:13:53 +00006893 cast<ConstantSDNode>(Offset)->isNullValue())
Evan Chenga7d4a042007-05-03 23:52:19 +00006894 return false;
Scott Michelfdc40a02009-02-17 22:15:04 +00006895
Chris Lattner41e53fd2006-11-11 01:00:15 +00006896 // Try turning it into a pre-indexed load / store except when:
Evan Chengc843abe2007-05-24 02:35:39 +00006897 // 1) The new base ptr is a frame index.
6898 // 2) If N is a store and the new base ptr is either the same as or is a
Chris Lattner9f1794e2006-11-11 00:56:29 +00006899 // predecessor of the value being stored.
Evan Chengc843abe2007-05-24 02:35:39 +00006900 // 3) Another use of old base ptr is a predecessor of N. If ptr is folded
Chris Lattner9f1794e2006-11-11 00:56:29 +00006901 // that would create a cycle.
Evan Chengc843abe2007-05-24 02:35:39 +00006902 // 4) All uses are load / store ops that use it as old base ptr.
Chris Lattner448f2192006-11-11 00:39:41 +00006903
Chris Lattner41e53fd2006-11-11 01:00:15 +00006904 // Check #1. Preinc'ing a frame index would require copying the stack pointer
6905 // (plus the implicit offset) to a register to preinc anyway.
Evan Chengcaab1292009-05-06 18:25:01 +00006906 if (isa<FrameIndexSDNode>(BasePtr) || isa<RegisterSDNode>(BasePtr))
Chris Lattner41e53fd2006-11-11 01:00:15 +00006907 return false;
Scott Michelfdc40a02009-02-17 22:15:04 +00006908
Chris Lattner41e53fd2006-11-11 01:00:15 +00006909 // Check #2.
Chris Lattner9f1794e2006-11-11 00:56:29 +00006910 if (!isLoad) {
Dan Gohman475871a2008-07-27 21:46:04 +00006911 SDValue Val = cast<StoreSDNode>(N)->getValue();
Gabor Greifba36cb52008-08-28 21:40:38 +00006912 if (Val == BasePtr || BasePtr.getNode()->isPredecessorOf(Val.getNode()))
Chris Lattner9f1794e2006-11-11 00:56:29 +00006913 return false;
Chris Lattner448f2192006-11-11 00:39:41 +00006914 }
Chris Lattner9f1794e2006-11-11 00:56:29 +00006915
Evan Chengc843abe2007-05-24 02:35:39 +00006916 // Now check for #3 and #4.
Chris Lattner9f1794e2006-11-11 00:56:29 +00006917 bool RealUse = false;
Lang Hames944520f2011-07-07 04:31:51 +00006918
6919 // Caches for hasPredecessorHelper
6920 SmallPtrSet<const SDNode *, 32> Visited;
6921 SmallVector<const SDNode *, 16> Worklist;
6922
Gabor Greifba36cb52008-08-28 21:40:38 +00006923 for (SDNode::use_iterator I = Ptr.getNode()->use_begin(),
6924 E = Ptr.getNode()->use_end(); I != E; ++I) {
Dan Gohman89684502008-07-27 20:43:25 +00006925 SDNode *Use = *I;
Chris Lattner9f1794e2006-11-11 00:56:29 +00006926 if (Use == N)
6927 continue;
Lang Hames944520f2011-07-07 04:31:51 +00006928 if (N->hasPredecessorHelper(Use, Visited, Worklist))
Chris Lattner9f1794e2006-11-11 00:56:29 +00006929 return false;
6930
Evan Chengc4b527a2012-01-13 01:37:24 +00006931 // If Ptr may be folded in addressing mode of other use, then it's
6932 // not profitable to do this transformation.
6933 if (!canFoldInAddressingMode(Ptr.getNode(), Use, DAG, TLI))
Chris Lattner9f1794e2006-11-11 00:56:29 +00006934 RealUse = true;
6935 }
Bill Wendlingc0debad2009-01-30 23:27:35 +00006936
Chris Lattner9f1794e2006-11-11 00:56:29 +00006937 if (!RealUse)
6938 return false;
6939
Dan Gohman475871a2008-07-27 21:46:04 +00006940 SDValue Result;
Chris Lattner9f1794e2006-11-11 00:56:29 +00006941 if (isLoad)
Bill Wendlingc0debad2009-01-30 23:27:35 +00006942 Result = DAG.getIndexedLoad(SDValue(N,0), N->getDebugLoc(),
6943 BasePtr, Offset, AM);
Chris Lattner9f1794e2006-11-11 00:56:29 +00006944 else
Bill Wendlingc0debad2009-01-30 23:27:35 +00006945 Result = DAG.getIndexedStore(SDValue(N,0), N->getDebugLoc(),
6946 BasePtr, Offset, AM);
Chris Lattner9f1794e2006-11-11 00:56:29 +00006947 ++PreIndexedNodes;
6948 ++NodesCombined;
David Greenef1090292010-01-05 01:25:00 +00006949 DEBUG(dbgs() << "\nReplacing.4 ";
Chris Lattnerbbbfa992009-08-23 06:35:02 +00006950 N->dump(&DAG);
David Greenef1090292010-01-05 01:25:00 +00006951 dbgs() << "\nWith: ";
Chris Lattnerbbbfa992009-08-23 06:35:02 +00006952 Result.getNode()->dump(&DAG);
David Greenef1090292010-01-05 01:25:00 +00006953 dbgs() << '\n');
Chris Lattnerf8dc0612008-02-03 06:49:24 +00006954 WorkListRemover DeadNodes(*this);
Chris Lattner9f1794e2006-11-11 00:56:29 +00006955 if (isLoad) {
Jakob Stoklund Olesenbc7d4482012-04-20 22:08:46 +00006956 DAG.ReplaceAllUsesOfValueWith(SDValue(N, 0), Result.getValue(0));
6957 DAG.ReplaceAllUsesOfValueWith(SDValue(N, 1), Result.getValue(2));
Chris Lattner9f1794e2006-11-11 00:56:29 +00006958 } else {
Jakob Stoklund Olesenbc7d4482012-04-20 22:08:46 +00006959 DAG.ReplaceAllUsesOfValueWith(SDValue(N, 0), Result.getValue(1));
Chris Lattner9f1794e2006-11-11 00:56:29 +00006960 }
6961
Chris Lattner9f1794e2006-11-11 00:56:29 +00006962 // Finally, since the node is now dead, remove it from the graph.
6963 DAG.DeleteNode(N);
6964
6965 // Replace the uses of Ptr with uses of the updated base value.
Jakob Stoklund Olesenbc7d4482012-04-20 22:08:46 +00006966 DAG.ReplaceAllUsesOfValueWith(Ptr, Result.getValue(isLoad ? 1 : 0));
Gabor Greifba36cb52008-08-28 21:40:38 +00006967 removeFromWorkList(Ptr.getNode());
6968 DAG.DeleteNode(Ptr.getNode());
Chris Lattner9f1794e2006-11-11 00:56:29 +00006969
6970 return true;
Chris Lattner448f2192006-11-11 00:39:41 +00006971}
6972
Duncan Sandsec87aa82008-06-15 20:12:31 +00006973/// CombineToPostIndexedLoadStore - Try to combine a load / store with a
Chris Lattner448f2192006-11-11 00:39:41 +00006974/// add / sub of the base pointer node into a post-indexed load / store.
6975/// The transformation folded the add / subtract into the new indexed
6976/// load / store effectively and all of its uses are redirected to the
6977/// new load / store.
6978bool DAGCombiner::CombineToPostIndexedLoadStore(SDNode *N) {
Eli Friedman50185242011-11-12 00:35:34 +00006979 if (Level < AfterLegalizeDAG)
Chris Lattner448f2192006-11-11 00:39:41 +00006980 return false;
6981
6982 bool isLoad = true;
Dan Gohman475871a2008-07-27 21:46:04 +00006983 SDValue Ptr;
Owen Andersone50ed302009-08-10 22:56:29 +00006984 EVT VT;
Chris Lattner448f2192006-11-11 00:39:41 +00006985 if (LoadSDNode *LD = dyn_cast<LoadSDNode>(N)) {
Chris Lattnerddf89562008-01-17 19:59:44 +00006986 if (LD->isIndexed())
Evan Chenge90460e2006-12-16 06:25:23 +00006987 return false;
Dan Gohmanb625f2f2008-01-30 00:15:11 +00006988 VT = LD->getMemoryVT();
Chris Lattner448f2192006-11-11 00:39:41 +00006989 if (!TLI.isIndexedLoadLegal(ISD::POST_INC, VT) &&
6990 !TLI.isIndexedLoadLegal(ISD::POST_DEC, VT))
6991 return false;
6992 Ptr = LD->getBasePtr();
6993 } else if (StoreSDNode *ST = dyn_cast<StoreSDNode>(N)) {
Chris Lattnerddf89562008-01-17 19:59:44 +00006994 if (ST->isIndexed())
Evan Chenge90460e2006-12-16 06:25:23 +00006995 return false;
Dan Gohmanb625f2f2008-01-30 00:15:11 +00006996 VT = ST->getMemoryVT();
Chris Lattner448f2192006-11-11 00:39:41 +00006997 if (!TLI.isIndexedStoreLegal(ISD::POST_INC, VT) &&
6998 !TLI.isIndexedStoreLegal(ISD::POST_DEC, VT))
6999 return false;
7000 Ptr = ST->getBasePtr();
7001 isLoad = false;
Bill Wendlingc0debad2009-01-30 23:27:35 +00007002 } else {
Chris Lattner448f2192006-11-11 00:39:41 +00007003 return false;
Bill Wendlingc0debad2009-01-30 23:27:35 +00007004 }
Chris Lattner448f2192006-11-11 00:39:41 +00007005
Gabor Greifba36cb52008-08-28 21:40:38 +00007006 if (Ptr.getNode()->hasOneUse())
Chris Lattner9f1794e2006-11-11 00:56:29 +00007007 return false;
Scott Michelfdc40a02009-02-17 22:15:04 +00007008
Gabor Greifba36cb52008-08-28 21:40:38 +00007009 for (SDNode::use_iterator I = Ptr.getNode()->use_begin(),
7010 E = Ptr.getNode()->use_end(); I != E; ++I) {
Dan Gohman89684502008-07-27 20:43:25 +00007011 SDNode *Op = *I;
Chris Lattner9f1794e2006-11-11 00:56:29 +00007012 if (Op == N ||
7013 (Op->getOpcode() != ISD::ADD && Op->getOpcode() != ISD::SUB))
7014 continue;
7015
Dan Gohman475871a2008-07-27 21:46:04 +00007016 SDValue BasePtr;
7017 SDValue Offset;
Chris Lattner9f1794e2006-11-11 00:56:29 +00007018 ISD::MemIndexedMode AM = ISD::UNINDEXED;
7019 if (TLI.getPostIndexedAddressParts(N, Op, BasePtr, Offset, AM, DAG)) {
Evan Chenga7d4a042007-05-03 23:52:19 +00007020 // Don't create a indexed load / store with zero offset.
7021 if (isa<ConstantSDNode>(Offset) &&
Dan Gohman002e5d02008-03-13 22:13:53 +00007022 cast<ConstantSDNode>(Offset)->isNullValue())
Evan Chenga7d4a042007-05-03 23:52:19 +00007023 continue;
Chris Lattner448f2192006-11-11 00:39:41 +00007024
Chris Lattner9f1794e2006-11-11 00:56:29 +00007025 // Try turning it into a post-indexed load / store except when
Evan Chengc4b527a2012-01-13 01:37:24 +00007026 // 1) All uses are load / store ops that use it as base ptr (and
7027 // it may be folded as addressing mmode).
Chris Lattner9f1794e2006-11-11 00:56:29 +00007028 // 2) Op must be independent of N, i.e. Op is neither a predecessor
7029 // nor a successor of N. Otherwise, if Op is folded that would
7030 // create a cycle.
7031
Evan Chengcaab1292009-05-06 18:25:01 +00007032 if (isa<FrameIndexSDNode>(BasePtr) || isa<RegisterSDNode>(BasePtr))
7033 continue;
7034
Chris Lattner9f1794e2006-11-11 00:56:29 +00007035 // Check for #1.
7036 bool TryNext = false;
Gabor Greifba36cb52008-08-28 21:40:38 +00007037 for (SDNode::use_iterator II = BasePtr.getNode()->use_begin(),
7038 EE = BasePtr.getNode()->use_end(); II != EE; ++II) {
Dan Gohman89684502008-07-27 20:43:25 +00007039 SDNode *Use = *II;
Gabor Greifba36cb52008-08-28 21:40:38 +00007040 if (Use == Ptr.getNode())
Chris Lattner448f2192006-11-11 00:39:41 +00007041 continue;
7042
Chris Lattner9f1794e2006-11-11 00:56:29 +00007043 // If all the uses are load / store addresses, then don't do the
7044 // transformation.
7045 if (Use->getOpcode() == ISD::ADD || Use->getOpcode() == ISD::SUB){
7046 bool RealUse = false;
7047 for (SDNode::use_iterator III = Use->use_begin(),
7048 EEE = Use->use_end(); III != EEE; ++III) {
Dan Gohman89684502008-07-27 20:43:25 +00007049 SDNode *UseUse = *III;
Evan Chengc4b527a2012-01-13 01:37:24 +00007050 if (!canFoldInAddressingMode(Use, UseUse, DAG, TLI))
Chris Lattner9f1794e2006-11-11 00:56:29 +00007051 RealUse = true;
7052 }
Chris Lattner448f2192006-11-11 00:39:41 +00007053
Chris Lattner9f1794e2006-11-11 00:56:29 +00007054 if (!RealUse) {
7055 TryNext = true;
7056 break;
Chris Lattner448f2192006-11-11 00:39:41 +00007057 }
7058 }
Chris Lattner9f1794e2006-11-11 00:56:29 +00007059 }
Bill Wendlingc0debad2009-01-30 23:27:35 +00007060
Chris Lattner9f1794e2006-11-11 00:56:29 +00007061 if (TryNext)
7062 continue;
Chris Lattner448f2192006-11-11 00:39:41 +00007063
Chris Lattner9f1794e2006-11-11 00:56:29 +00007064 // Check for #2
Evan Cheng917be682008-03-04 00:41:45 +00007065 if (!Op->isPredecessorOf(N) && !N->isPredecessorOf(Op)) {
Dan Gohman475871a2008-07-27 21:46:04 +00007066 SDValue Result = isLoad
Bill Wendlingc0debad2009-01-30 23:27:35 +00007067 ? DAG.getIndexedLoad(SDValue(N,0), N->getDebugLoc(),
7068 BasePtr, Offset, AM)
7069 : DAG.getIndexedStore(SDValue(N,0), N->getDebugLoc(),
7070 BasePtr, Offset, AM);
Chris Lattner9f1794e2006-11-11 00:56:29 +00007071 ++PostIndexedNodes;
7072 ++NodesCombined;
David Greenef1090292010-01-05 01:25:00 +00007073 DEBUG(dbgs() << "\nReplacing.5 ";
Chris Lattnerbbbfa992009-08-23 06:35:02 +00007074 N->dump(&DAG);
David Greenef1090292010-01-05 01:25:00 +00007075 dbgs() << "\nWith: ";
Chris Lattnerbbbfa992009-08-23 06:35:02 +00007076 Result.getNode()->dump(&DAG);
David Greenef1090292010-01-05 01:25:00 +00007077 dbgs() << '\n');
Chris Lattnerf8dc0612008-02-03 06:49:24 +00007078 WorkListRemover DeadNodes(*this);
Chris Lattner9f1794e2006-11-11 00:56:29 +00007079 if (isLoad) {
Jakob Stoklund Olesenbc7d4482012-04-20 22:08:46 +00007080 DAG.ReplaceAllUsesOfValueWith(SDValue(N, 0), Result.getValue(0));
7081 DAG.ReplaceAllUsesOfValueWith(SDValue(N, 1), Result.getValue(2));
Chris Lattner9f1794e2006-11-11 00:56:29 +00007082 } else {
Jakob Stoklund Olesenbc7d4482012-04-20 22:08:46 +00007083 DAG.ReplaceAllUsesOfValueWith(SDValue(N, 0), Result.getValue(1));
Chris Lattner448f2192006-11-11 00:39:41 +00007084 }
Chris Lattner9f1794e2006-11-11 00:56:29 +00007085
Chris Lattner9f1794e2006-11-11 00:56:29 +00007086 // Finally, since the node is now dead, remove it from the graph.
7087 DAG.DeleteNode(N);
7088
7089 // Replace the uses of Use with uses of the updated base value.
Dan Gohman475871a2008-07-27 21:46:04 +00007090 DAG.ReplaceAllUsesOfValueWith(SDValue(Op, 0),
Jakob Stoklund Olesenbc7d4482012-04-20 22:08:46 +00007091 Result.getValue(isLoad ? 1 : 0));
Chris Lattner9f1794e2006-11-11 00:56:29 +00007092 removeFromWorkList(Op);
Chris Lattner9f1794e2006-11-11 00:56:29 +00007093 DAG.DeleteNode(Op);
Chris Lattner9f1794e2006-11-11 00:56:29 +00007094 return true;
Chris Lattner448f2192006-11-11 00:39:41 +00007095 }
7096 }
7097 }
Bill Wendlingc0debad2009-01-30 23:27:35 +00007098
Chris Lattner448f2192006-11-11 00:39:41 +00007099 return false;
7100}
7101
Dan Gohman475871a2008-07-27 21:46:04 +00007102SDValue DAGCombiner::visitLOAD(SDNode *N) {
Evan Cheng466685d2006-10-09 20:57:25 +00007103 LoadSDNode *LD = cast<LoadSDNode>(N);
Dan Gohman475871a2008-07-27 21:46:04 +00007104 SDValue Chain = LD->getChain();
7105 SDValue Ptr = LD->getBasePtr();
Scott Michelfdc40a02009-02-17 22:15:04 +00007106
Evan Cheng45a7ca92007-05-01 00:38:21 +00007107 // If load is not volatile and there are no uses of the loaded value (and
7108 // the updated indexed value in case of indexed loads), change uses of the
7109 // chain value into uses of the chain input (i.e. delete the dead load).
7110 if (!LD->isVolatile()) {
Owen Anderson825b72b2009-08-11 20:47:22 +00007111 if (N->getValueType(1) == MVT::Other) {
Evan Cheng498f5592007-05-01 08:53:39 +00007112 // Unindexed loads.
Craig Topper704e1a02012-01-07 18:31:09 +00007113 if (!N->hasAnyUseOfValue(0)) {
Evan Cheng02c42852008-01-16 23:11:54 +00007114 // It's not safe to use the two value CombineTo variant here. e.g.
7115 // v1, chain2 = load chain1, loc
7116 // v2, chain3 = load chain2, loc
7117 // v3 = add v2, c
Chris Lattner125991a2008-01-24 07:57:06 +00007118 // Now we replace use of chain2 with chain1. This makes the second load
7119 // isomorphic to the one we are deleting, and thus makes this load live.
David Greenef1090292010-01-05 01:25:00 +00007120 DEBUG(dbgs() << "\nReplacing.6 ";
Chris Lattnerbbbfa992009-08-23 06:35:02 +00007121 N->dump(&DAG);
David Greenef1090292010-01-05 01:25:00 +00007122 dbgs() << "\nWith chain: ";
Chris Lattnerbbbfa992009-08-23 06:35:02 +00007123 Chain.getNode()->dump(&DAG);
David Greenef1090292010-01-05 01:25:00 +00007124 dbgs() << "\n");
Chris Lattnerf8dc0612008-02-03 06:49:24 +00007125 WorkListRemover DeadNodes(*this);
Jakob Stoklund Olesenbc7d4482012-04-20 22:08:46 +00007126 DAG.ReplaceAllUsesOfValueWith(SDValue(N, 1), Chain);
Bill Wendlingc0debad2009-01-30 23:27:35 +00007127
Chris Lattner125991a2008-01-24 07:57:06 +00007128 if (N->use_empty()) {
7129 removeFromWorkList(N);
7130 DAG.DeleteNode(N);
7131 }
Bill Wendlingc0debad2009-01-30 23:27:35 +00007132
Dan Gohman475871a2008-07-27 21:46:04 +00007133 return SDValue(N, 0); // Return N so it doesn't get rechecked!
Evan Cheng02c42852008-01-16 23:11:54 +00007134 }
Evan Cheng498f5592007-05-01 08:53:39 +00007135 } else {
7136 // Indexed loads.
Owen Anderson825b72b2009-08-11 20:47:22 +00007137 assert(N->getValueType(2) == MVT::Other && "Malformed indexed loads?");
Craig Topper704e1a02012-01-07 18:31:09 +00007138 if (!N->hasAnyUseOfValue(0) && !N->hasAnyUseOfValue(1)) {
Dale Johannesene8d72302009-02-06 23:05:02 +00007139 SDValue Undef = DAG.getUNDEF(N->getValueType(0));
Evan Cheng2c755ba2010-02-27 07:36:59 +00007140 DEBUG(dbgs() << "\nReplacing.7 ";
Chris Lattnerbbbfa992009-08-23 06:35:02 +00007141 N->dump(&DAG);
David Greenef1090292010-01-05 01:25:00 +00007142 dbgs() << "\nWith: ";
Chris Lattnerbbbfa992009-08-23 06:35:02 +00007143 Undef.getNode()->dump(&DAG);
David Greenef1090292010-01-05 01:25:00 +00007144 dbgs() << " and 2 other values\n");
Chris Lattnerf8dc0612008-02-03 06:49:24 +00007145 WorkListRemover DeadNodes(*this);
Jakob Stoklund Olesenbc7d4482012-04-20 22:08:46 +00007146 DAG.ReplaceAllUsesOfValueWith(SDValue(N, 0), Undef);
Dan Gohman475871a2008-07-27 21:46:04 +00007147 DAG.ReplaceAllUsesOfValueWith(SDValue(N, 1),
Jakob Stoklund Olesenbc7d4482012-04-20 22:08:46 +00007148 DAG.getUNDEF(N->getValueType(1)));
7149 DAG.ReplaceAllUsesOfValueWith(SDValue(N, 2), Chain);
Evan Cheng02c42852008-01-16 23:11:54 +00007150 removeFromWorkList(N);
Evan Cheng02c42852008-01-16 23:11:54 +00007151 DAG.DeleteNode(N);
Dan Gohman475871a2008-07-27 21:46:04 +00007152 return SDValue(N, 0); // Return N so it doesn't get rechecked!
Evan Cheng45a7ca92007-05-01 00:38:21 +00007153 }
Evan Cheng45a7ca92007-05-01 00:38:21 +00007154 }
7155 }
Scott Michelfdc40a02009-02-17 22:15:04 +00007156
Chris Lattner01a22022005-10-10 22:04:48 +00007157 // If this load is directly stored, replace the load value with the stored
7158 // value.
7159 // TODO: Handle store large -> read small portion.
Jim Laskeyc2b19f32006-10-11 17:47:52 +00007160 // TODO: Handle TRUNCSTORE/LOADEXT
Evan Cheng9ef82ce2011-03-11 00:48:56 +00007161 if (ISD::isNormalLoad(N) && !LD->isVolatile()) {
Gabor Greifba36cb52008-08-28 21:40:38 +00007162 if (ISD::isNON_TRUNCStore(Chain.getNode())) {
Evan Cheng8b2794a2006-10-13 21:14:26 +00007163 StoreSDNode *PrevST = cast<StoreSDNode>(Chain);
7164 if (PrevST->getBasePtr() == Ptr &&
7165 PrevST->getValue().getValueType() == N->getValueType(0))
Jim Laskeyc2b19f32006-10-11 17:47:52 +00007166 return CombineTo(N, Chain.getOperand(1), Chain);
Evan Cheng8b2794a2006-10-13 21:14:26 +00007167 }
Jim Laskeyc2b19f32006-10-11 17:47:52 +00007168 }
Scott Michelfdc40a02009-02-17 22:15:04 +00007169
Evan Cheng255f20f2010-04-01 06:04:33 +00007170 // Try to infer better alignment information than the load already has.
7171 if (OptLevel != CodeGenOpt::None && LD->isUnindexed()) {
Evan Chenged1c0c72011-11-28 22:37:34 +00007172 if (unsigned Align = DAG.InferPtrAlignment(Ptr)) {
7173 if (Align > LD->getAlignment())
7174 return DAG.getExtLoad(LD->getExtensionType(), N->getDebugLoc(),
7175 LD->getValueType(0),
7176 Chain, Ptr, LD->getPointerInfo(),
7177 LD->getMemoryVT(),
7178 LD->isVolatile(), LD->isNonTemporal(), Align);
Evan Cheng255f20f2010-04-01 06:04:33 +00007179 }
7180 }
7181
Jim Laskey7ca56af2006-10-11 13:47:09 +00007182 if (CombinerAA) {
Jim Laskey279f0532006-09-25 16:29:54 +00007183 // Walk up chain skipping non-aliasing memory nodes.
Dan Gohman475871a2008-07-27 21:46:04 +00007184 SDValue BetterChain = FindBetterChain(N, Chain);
Scott Michelfdc40a02009-02-17 22:15:04 +00007185
Jim Laskey6ff23e52006-10-04 16:53:27 +00007186 // If there is a better chain.
Jim Laskey279f0532006-09-25 16:29:54 +00007187 if (Chain != BetterChain) {
Dan Gohman475871a2008-07-27 21:46:04 +00007188 SDValue ReplLoad;
Jim Laskeyc2b19f32006-10-11 17:47:52 +00007189
Jim Laskey279f0532006-09-25 16:29:54 +00007190 // Replace the chain to void dependency.
Jim Laskeyc2b19f32006-10-11 17:47:52 +00007191 if (LD->getExtensionType() == ISD::NON_EXTLOAD) {
Bill Wendlingc0debad2009-01-30 23:27:35 +00007192 ReplLoad = DAG.getLoad(N->getValueType(0), LD->getDebugLoc(),
Chris Lattnerfa459012010-09-21 16:08:50 +00007193 BetterChain, Ptr, LD->getPointerInfo(),
David Greene1e559442010-02-15 17:00:31 +00007194 LD->isVolatile(), LD->isNonTemporal(),
Pete Cooperd752e0f2011-11-08 18:42:53 +00007195 LD->isInvariant(), LD->getAlignment());
Jim Laskeyc2b19f32006-10-11 17:47:52 +00007196 } else {
Stuart Hastingsa9011292011-02-16 16:23:55 +00007197 ReplLoad = DAG.getExtLoad(LD->getExtensionType(), LD->getDebugLoc(),
7198 LD->getValueType(0),
Chris Lattnerfa459012010-09-21 16:08:50 +00007199 BetterChain, Ptr, LD->getPointerInfo(),
Dan Gohmanb625f2f2008-01-30 00:15:11 +00007200 LD->getMemoryVT(),
Scott Michelfdc40a02009-02-17 22:15:04 +00007201 LD->isVolatile(),
David Greene1e559442010-02-15 17:00:31 +00007202 LD->isNonTemporal(),
Christopher Lamb95c218a2007-04-22 23:15:30 +00007203 LD->getAlignment());
Jim Laskeyc2b19f32006-10-11 17:47:52 +00007204 }
Jim Laskey279f0532006-09-25 16:29:54 +00007205
Jim Laskey6ff23e52006-10-04 16:53:27 +00007206 // Create token factor to keep old chain connected.
Bill Wendlingc0debad2009-01-30 23:27:35 +00007207 SDValue Token = DAG.getNode(ISD::TokenFactor, N->getDebugLoc(),
Owen Anderson825b72b2009-08-11 20:47:22 +00007208 MVT::Other, Chain, ReplLoad.getValue(1));
Wesley Peckbf17cfa2010-11-23 03:31:01 +00007209
Nate Begemanb6aef5c2009-09-15 00:18:30 +00007210 // Make sure the new and old chains are cleaned up.
7211 AddToWorkList(Token.getNode());
Wesley Peckbf17cfa2010-11-23 03:31:01 +00007212
Jim Laskey274062c2006-10-13 23:32:28 +00007213 // Replace uses with load result and token factor. Don't add users
7214 // to work list.
7215 return CombineTo(N, ReplLoad.getValue(0), Token, false);
Jim Laskey279f0532006-09-25 16:29:54 +00007216 }
7217 }
7218
Evan Cheng7fc033a2006-11-03 03:06:21 +00007219 // Try transforming N to an indexed load.
Evan Chengbbd6f6e2006-11-07 09:03:05 +00007220 if (CombineToPreIndexedLoadStore(N) || CombineToPostIndexedLoadStore(N))
Dan Gohman475871a2008-07-27 21:46:04 +00007221 return SDValue(N, 0);
Evan Cheng7fc033a2006-11-03 03:06:21 +00007222
Dan Gohman475871a2008-07-27 21:46:04 +00007223 return SDValue();
Chris Lattner01a22022005-10-10 22:04:48 +00007224}
7225
Chris Lattner2392ae72010-04-15 04:48:01 +00007226/// CheckForMaskedLoad - Check to see if V is (and load (ptr), imm), where the
7227/// load is having specific bytes cleared out. If so, return the byte size
7228/// being masked out and the shift amount.
7229static std::pair<unsigned, unsigned>
7230CheckForMaskedLoad(SDValue V, SDValue Ptr, SDValue Chain) {
7231 std::pair<unsigned, unsigned> Result(0, 0);
Wesley Peckbf17cfa2010-11-23 03:31:01 +00007232
Chris Lattner2392ae72010-04-15 04:48:01 +00007233 // Check for the structure we're looking for.
7234 if (V->getOpcode() != ISD::AND ||
7235 !isa<ConstantSDNode>(V->getOperand(1)) ||
7236 !ISD::isNormalLoad(V->getOperand(0).getNode()))
7237 return Result;
Wesley Peckbf17cfa2010-11-23 03:31:01 +00007238
Chris Lattnere6987582010-04-15 06:10:49 +00007239 // Check the chain and pointer.
Chris Lattner2392ae72010-04-15 04:48:01 +00007240 LoadSDNode *LD = cast<LoadSDNode>(V->getOperand(0));
Chris Lattnere6987582010-04-15 06:10:49 +00007241 if (LD->getBasePtr() != Ptr) return Result; // Not from same pointer.
Wesley Peckbf17cfa2010-11-23 03:31:01 +00007242
Chris Lattnere6987582010-04-15 06:10:49 +00007243 // The store should be chained directly to the load or be an operand of a
7244 // tokenfactor.
7245 if (LD == Chain.getNode())
7246 ; // ok.
7247 else if (Chain->getOpcode() != ISD::TokenFactor)
7248 return Result; // Fail.
7249 else {
7250 bool isOk = false;
7251 for (unsigned i = 0, e = Chain->getNumOperands(); i != e; ++i)
7252 if (Chain->getOperand(i).getNode() == LD) {
7253 isOk = true;
7254 break;
7255 }
7256 if (!isOk) return Result;
7257 }
Wesley Peckbf17cfa2010-11-23 03:31:01 +00007258
Chris Lattner2392ae72010-04-15 04:48:01 +00007259 // This only handles simple types.
7260 if (V.getValueType() != MVT::i16 &&
7261 V.getValueType() != MVT::i32 &&
7262 V.getValueType() != MVT::i64)
7263 return Result;
7264
7265 // Check the constant mask. Invert it so that the bits being masked out are
7266 // 0 and the bits being kept are 1. Use getSExtValue so that leading bits
7267 // follow the sign bit for uniformity.
7268 uint64_t NotMask = ~cast<ConstantSDNode>(V->getOperand(1))->getSExtValue();
7269 unsigned NotMaskLZ = CountLeadingZeros_64(NotMask);
7270 if (NotMaskLZ & 7) return Result; // Must be multiple of a byte.
7271 unsigned NotMaskTZ = CountTrailingZeros_64(NotMask);
7272 if (NotMaskTZ & 7) return Result; // Must be multiple of a byte.
7273 if (NotMaskLZ == 64) return Result; // All zero mask.
Wesley Peckbf17cfa2010-11-23 03:31:01 +00007274
Chris Lattner2392ae72010-04-15 04:48:01 +00007275 // See if we have a continuous run of bits. If so, we have 0*1+0*
7276 if (CountTrailingOnes_64(NotMask >> NotMaskTZ)+NotMaskTZ+NotMaskLZ != 64)
7277 return Result;
7278
7279 // Adjust NotMaskLZ down to be from the actual size of the int instead of i64.
7280 if (V.getValueType() != MVT::i64 && NotMaskLZ)
7281 NotMaskLZ -= 64-V.getValueSizeInBits();
Wesley Peckbf17cfa2010-11-23 03:31:01 +00007282
Chris Lattner2392ae72010-04-15 04:48:01 +00007283 unsigned MaskedBytes = (V.getValueSizeInBits()-NotMaskLZ-NotMaskTZ)/8;
7284 switch (MaskedBytes) {
Wesley Peckbf17cfa2010-11-23 03:31:01 +00007285 case 1:
7286 case 2:
Chris Lattner2392ae72010-04-15 04:48:01 +00007287 case 4: break;
7288 default: return Result; // All one mask, or 5-byte mask.
7289 }
Wesley Peckbf17cfa2010-11-23 03:31:01 +00007290
Chris Lattner2392ae72010-04-15 04:48:01 +00007291 // Verify that the first bit starts at a multiple of mask so that the access
7292 // is aligned the same as the access width.
7293 if (NotMaskTZ && NotMaskTZ/8 % MaskedBytes) return Result;
Wesley Peckbf17cfa2010-11-23 03:31:01 +00007294
Chris Lattner2392ae72010-04-15 04:48:01 +00007295 Result.first = MaskedBytes;
7296 Result.second = NotMaskTZ/8;
7297 return Result;
7298}
7299
7300
7301/// ShrinkLoadReplaceStoreWithStore - Check to see if IVal is something that
7302/// provides a value as specified by MaskInfo. If so, replace the specified
7303/// store with a narrower store of truncated IVal.
7304static SDNode *
7305ShrinkLoadReplaceStoreWithStore(const std::pair<unsigned, unsigned> &MaskInfo,
7306 SDValue IVal, StoreSDNode *St,
7307 DAGCombiner *DC) {
7308 unsigned NumBytes = MaskInfo.first;
7309 unsigned ByteShift = MaskInfo.second;
7310 SelectionDAG &DAG = DC->getDAG();
Wesley Peckbf17cfa2010-11-23 03:31:01 +00007311
Chris Lattner2392ae72010-04-15 04:48:01 +00007312 // Check to see if IVal is all zeros in the part being masked in by the 'or'
7313 // that uses this. If not, this is not a replacement.
7314 APInt Mask = ~APInt::getBitsSet(IVal.getValueSizeInBits(),
7315 ByteShift*8, (ByteShift+NumBytes)*8);
7316 if (!DAG.MaskedValueIsZero(IVal, Mask)) return 0;
Wesley Peckbf17cfa2010-11-23 03:31:01 +00007317
Chris Lattner2392ae72010-04-15 04:48:01 +00007318 // Check that it is legal on the target to do this. It is legal if the new
7319 // VT we're shrinking to (i8/i16/i32) is legal or we're still before type
7320 // legalization.
7321 MVT VT = MVT::getIntegerVT(NumBytes*8);
7322 if (!DC->isTypeLegal(VT))
7323 return 0;
Wesley Peckbf17cfa2010-11-23 03:31:01 +00007324
Chris Lattner2392ae72010-04-15 04:48:01 +00007325 // Okay, we can do this! Replace the 'St' store with a store of IVal that is
7326 // shifted by ByteShift and truncated down to NumBytes.
7327 if (ByteShift)
7328 IVal = DAG.getNode(ISD::SRL, IVal->getDebugLoc(), IVal.getValueType(), IVal,
Owen Anderson95771af2011-02-25 21:41:48 +00007329 DAG.getConstant(ByteShift*8,
7330 DC->getShiftAmountTy(IVal.getValueType())));
Chris Lattner2392ae72010-04-15 04:48:01 +00007331
7332 // Figure out the offset for the store and the alignment of the access.
7333 unsigned StOffset;
7334 unsigned NewAlign = St->getAlignment();
7335
7336 if (DAG.getTargetLoweringInfo().isLittleEndian())
7337 StOffset = ByteShift;
7338 else
7339 StOffset = IVal.getValueType().getStoreSize() - ByteShift - NumBytes;
Wesley Peckbf17cfa2010-11-23 03:31:01 +00007340
Chris Lattner2392ae72010-04-15 04:48:01 +00007341 SDValue Ptr = St->getBasePtr();
7342 if (StOffset) {
7343 Ptr = DAG.getNode(ISD::ADD, IVal->getDebugLoc(), Ptr.getValueType(),
7344 Ptr, DAG.getConstant(StOffset, Ptr.getValueType()));
7345 NewAlign = MinAlign(NewAlign, StOffset);
7346 }
Wesley Peckbf17cfa2010-11-23 03:31:01 +00007347
Chris Lattner2392ae72010-04-15 04:48:01 +00007348 // Truncate down to the new size.
7349 IVal = DAG.getNode(ISD::TRUNCATE, IVal->getDebugLoc(), VT, IVal);
Wesley Peckbf17cfa2010-11-23 03:31:01 +00007350
Chris Lattner2392ae72010-04-15 04:48:01 +00007351 ++OpsNarrowed;
Wesley Peckbf17cfa2010-11-23 03:31:01 +00007352 return DAG.getStore(St->getChain(), St->getDebugLoc(), IVal, Ptr,
Chris Lattner6229d0a2010-09-21 18:41:36 +00007353 St->getPointerInfo().getWithOffset(StOffset),
Chris Lattner2392ae72010-04-15 04:48:01 +00007354 false, false, NewAlign).getNode();
7355}
7356
Evan Cheng8b944d32009-05-28 00:35:15 +00007357
7358/// ReduceLoadOpStoreWidth - Look for sequence of load / op / store where op is
7359/// one of 'or', 'xor', and 'and' of immediates. If 'op' is only touching some
7360/// of the loaded bits, try narrowing the load and store if it would end up
7361/// being a win for performance or code size.
7362SDValue DAGCombiner::ReduceLoadOpStoreWidth(SDNode *N) {
7363 StoreSDNode *ST = cast<StoreSDNode>(N);
Evan Chengcdcecc02009-05-28 18:41:02 +00007364 if (ST->isVolatile())
7365 return SDValue();
7366
Evan Cheng8b944d32009-05-28 00:35:15 +00007367 SDValue Chain = ST->getChain();
7368 SDValue Value = ST->getValue();
7369 SDValue Ptr = ST->getBasePtr();
Owen Andersone50ed302009-08-10 22:56:29 +00007370 EVT VT = Value.getValueType();
Evan Cheng8b944d32009-05-28 00:35:15 +00007371
7372 if (ST->isTruncatingStore() || VT.isVector() || !Value.hasOneUse())
Evan Chengcdcecc02009-05-28 18:41:02 +00007373 return SDValue();
Evan Cheng8b944d32009-05-28 00:35:15 +00007374
7375 unsigned Opc = Value.getOpcode();
Wesley Peckbf17cfa2010-11-23 03:31:01 +00007376
Chris Lattner2392ae72010-04-15 04:48:01 +00007377 // If this is "store (or X, Y), P" and X is "(and (load P), cst)", where cst
7378 // is a byte mask indicating a consecutive number of bytes, check to see if
7379 // Y is known to provide just those bytes. If so, we try to replace the
7380 // load + replace + store sequence with a single (narrower) store, which makes
7381 // the load dead.
7382 if (Opc == ISD::OR) {
7383 std::pair<unsigned, unsigned> MaskedLoad;
7384 MaskedLoad = CheckForMaskedLoad(Value.getOperand(0), Ptr, Chain);
7385 if (MaskedLoad.first)
7386 if (SDNode *NewST = ShrinkLoadReplaceStoreWithStore(MaskedLoad,
7387 Value.getOperand(1), ST,this))
7388 return SDValue(NewST, 0);
Wesley Peckbf17cfa2010-11-23 03:31:01 +00007389
Chris Lattner2392ae72010-04-15 04:48:01 +00007390 // Or is commutative, so try swapping X and Y.
7391 MaskedLoad = CheckForMaskedLoad(Value.getOperand(1), Ptr, Chain);
7392 if (MaskedLoad.first)
7393 if (SDNode *NewST = ShrinkLoadReplaceStoreWithStore(MaskedLoad,
7394 Value.getOperand(0), ST,this))
7395 return SDValue(NewST, 0);
7396 }
Wesley Peckbf17cfa2010-11-23 03:31:01 +00007397
Evan Cheng8b944d32009-05-28 00:35:15 +00007398 if ((Opc != ISD::OR && Opc != ISD::XOR && Opc != ISD::AND) ||
7399 Value.getOperand(1).getOpcode() != ISD::Constant)
Evan Chengcdcecc02009-05-28 18:41:02 +00007400 return SDValue();
Evan Cheng8b944d32009-05-28 00:35:15 +00007401
7402 SDValue N0 = Value.getOperand(0);
Dan Gohman24bde5b2010-09-02 21:18:42 +00007403 if (ISD::isNormalLoad(N0.getNode()) && N0.hasOneUse() &&
7404 Chain == SDValue(N0.getNode(), 1)) {
Evan Cheng8b944d32009-05-28 00:35:15 +00007405 LoadSDNode *LD = cast<LoadSDNode>(N0);
Chris Lattnerfa459012010-09-21 16:08:50 +00007406 if (LD->getBasePtr() != Ptr ||
7407 LD->getPointerInfo().getAddrSpace() !=
7408 ST->getPointerInfo().getAddrSpace())
Evan Chengcdcecc02009-05-28 18:41:02 +00007409 return SDValue();
Evan Cheng8b944d32009-05-28 00:35:15 +00007410
7411 // Find the type to narrow it the load / op / store to.
7412 SDValue N1 = Value.getOperand(1);
7413 unsigned BitWidth = N1.getValueSizeInBits();
7414 APInt Imm = cast<ConstantSDNode>(N1)->getAPIntValue();
7415 if (Opc == ISD::AND)
7416 Imm ^= APInt::getAllOnesValue(BitWidth);
Evan Chengd3c76bb2009-05-28 23:52:18 +00007417 if (Imm == 0 || Imm.isAllOnesValue())
7418 return SDValue();
Evan Cheng8b944d32009-05-28 00:35:15 +00007419 unsigned ShAmt = Imm.countTrailingZeros();
7420 unsigned MSB = BitWidth - Imm.countLeadingZeros() - 1;
7421 unsigned NewBW = NextPowerOf2(MSB - ShAmt);
Owen Anderson23b9b192009-08-12 00:36:31 +00007422 EVT NewVT = EVT::getIntegerVT(*DAG.getContext(), NewBW);
Evan Cheng8b944d32009-05-28 00:35:15 +00007423 while (NewBW < BitWidth &&
Evan Chengcdcecc02009-05-28 18:41:02 +00007424 !(TLI.isOperationLegalOrCustom(Opc, NewVT) &&
Evan Cheng8b944d32009-05-28 00:35:15 +00007425 TLI.isNarrowingProfitable(VT, NewVT))) {
7426 NewBW = NextPowerOf2(NewBW);
Owen Anderson23b9b192009-08-12 00:36:31 +00007427 NewVT = EVT::getIntegerVT(*DAG.getContext(), NewBW);
Evan Cheng8b944d32009-05-28 00:35:15 +00007428 }
Evan Chengcdcecc02009-05-28 18:41:02 +00007429 if (NewBW >= BitWidth)
7430 return SDValue();
Evan Cheng8b944d32009-05-28 00:35:15 +00007431
7432 // If the lsb changed does not start at the type bitwidth boundary,
7433 // start at the previous one.
7434 if (ShAmt % NewBW)
7435 ShAmt = (((ShAmt + NewBW - 1) / NewBW) * NewBW) - NewBW;
Manman Ren981b9632012-12-12 01:13:50 +00007436 APInt Mask = APInt::getBitsSet(BitWidth, ShAmt,
7437 std::min(BitWidth, ShAmt + NewBW));
Evan Cheng8b944d32009-05-28 00:35:15 +00007438 if ((Imm & Mask) == Imm) {
7439 APInt NewImm = (Imm & Mask).lshr(ShAmt).trunc(NewBW);
7440 if (Opc == ISD::AND)
7441 NewImm ^= APInt::getAllOnesValue(NewBW);
7442 uint64_t PtrOff = ShAmt / 8;
7443 // For big endian targets, we need to adjust the offset to the pointer to
7444 // load the correct bytes.
7445 if (TLI.isBigEndian())
Evan Chengcdcecc02009-05-28 18:41:02 +00007446 PtrOff = (BitWidth + 7 - NewBW) / 8 - PtrOff;
Evan Cheng8b944d32009-05-28 00:35:15 +00007447
7448 unsigned NewAlign = MinAlign(LD->getAlignment(), PtrOff);
Chris Lattnerdb125cf2011-07-18 04:54:35 +00007449 Type *NewVTTy = NewVT.getTypeForEVT(*DAG.getContext());
Micah Villmow3574eca2012-10-08 16:38:25 +00007450 if (NewAlign < TLI.getDataLayout()->getABITypeAlignment(NewVTTy))
Evan Chengcdcecc02009-05-28 18:41:02 +00007451 return SDValue();
7452
Evan Cheng8b944d32009-05-28 00:35:15 +00007453 SDValue NewPtr = DAG.getNode(ISD::ADD, LD->getDebugLoc(),
7454 Ptr.getValueType(), Ptr,
7455 DAG.getConstant(PtrOff, Ptr.getValueType()));
7456 SDValue NewLD = DAG.getLoad(NewVT, N0.getDebugLoc(),
7457 LD->getChain(), NewPtr,
Chris Lattnerfa459012010-09-21 16:08:50 +00007458 LD->getPointerInfo().getWithOffset(PtrOff),
David Greene1e559442010-02-15 17:00:31 +00007459 LD->isVolatile(), LD->isNonTemporal(),
Pete Cooperd752e0f2011-11-08 18:42:53 +00007460 LD->isInvariant(), NewAlign);
Evan Cheng8b944d32009-05-28 00:35:15 +00007461 SDValue NewVal = DAG.getNode(Opc, Value.getDebugLoc(), NewVT, NewLD,
7462 DAG.getConstant(NewImm, NewVT));
7463 SDValue NewST = DAG.getStore(Chain, N->getDebugLoc(),
7464 NewVal, NewPtr,
Chris Lattnerfa459012010-09-21 16:08:50 +00007465 ST->getPointerInfo().getWithOffset(PtrOff),
David Greene1e559442010-02-15 17:00:31 +00007466 false, false, NewAlign);
Evan Cheng8b944d32009-05-28 00:35:15 +00007467
7468 AddToWorkList(NewPtr.getNode());
7469 AddToWorkList(NewLD.getNode());
7470 AddToWorkList(NewVal.getNode());
7471 WorkListRemover DeadNodes(*this);
Jakob Stoklund Olesenbc7d4482012-04-20 22:08:46 +00007472 DAG.ReplaceAllUsesOfValueWith(N0.getValue(1), NewLD.getValue(1));
Evan Cheng8b944d32009-05-28 00:35:15 +00007473 ++OpsNarrowed;
7474 return NewST;
7475 }
7476 }
7477
Evan Chengcdcecc02009-05-28 18:41:02 +00007478 return SDValue();
Evan Cheng8b944d32009-05-28 00:35:15 +00007479}
7480
Evan Cheng31959b12011-02-02 01:06:55 +00007481/// TransformFPLoadStorePair - For a given floating point load / store pair,
7482/// if the load value isn't used by any other operations, then consider
7483/// transforming the pair to integer load / store operations if the target
7484/// deems the transformation profitable.
7485SDValue DAGCombiner::TransformFPLoadStorePair(SDNode *N) {
7486 StoreSDNode *ST = cast<StoreSDNode>(N);
7487 SDValue Chain = ST->getChain();
7488 SDValue Value = ST->getValue();
7489 if (ISD::isNormalStore(ST) && ISD::isNormalLoad(Value.getNode()) &&
7490 Value.hasOneUse() &&
7491 Chain == SDValue(Value.getNode(), 1)) {
7492 LoadSDNode *LD = cast<LoadSDNode>(Value);
7493 EVT VT = LD->getMemoryVT();
7494 if (!VT.isFloatingPoint() ||
7495 VT != ST->getMemoryVT() ||
7496 LD->isNonTemporal() ||
7497 ST->isNonTemporal() ||
7498 LD->getPointerInfo().getAddrSpace() != 0 ||
7499 ST->getPointerInfo().getAddrSpace() != 0)
7500 return SDValue();
7501
7502 EVT IntVT = EVT::getIntegerVT(*DAG.getContext(), VT.getSizeInBits());
7503 if (!TLI.isOperationLegal(ISD::LOAD, IntVT) ||
7504 !TLI.isOperationLegal(ISD::STORE, IntVT) ||
7505 !TLI.isDesirableToTransformToIntegerOp(ISD::LOAD, VT) ||
7506 !TLI.isDesirableToTransformToIntegerOp(ISD::STORE, VT))
7507 return SDValue();
7508
7509 unsigned LDAlign = LD->getAlignment();
7510 unsigned STAlign = ST->getAlignment();
Chris Lattnerdb125cf2011-07-18 04:54:35 +00007511 Type *IntVTTy = IntVT.getTypeForEVT(*DAG.getContext());
Micah Villmow3574eca2012-10-08 16:38:25 +00007512 unsigned ABIAlign = TLI.getDataLayout()->getABITypeAlignment(IntVTTy);
Evan Cheng31959b12011-02-02 01:06:55 +00007513 if (LDAlign < ABIAlign || STAlign < ABIAlign)
7514 return SDValue();
7515
7516 SDValue NewLD = DAG.getLoad(IntVT, Value.getDebugLoc(),
7517 LD->getChain(), LD->getBasePtr(),
7518 LD->getPointerInfo(),
Pete Cooperd752e0f2011-11-08 18:42:53 +00007519 false, false, false, LDAlign);
Evan Cheng31959b12011-02-02 01:06:55 +00007520
7521 SDValue NewST = DAG.getStore(NewLD.getValue(1), N->getDebugLoc(),
7522 NewLD, ST->getBasePtr(),
7523 ST->getPointerInfo(),
7524 false, false, STAlign);
7525
7526 AddToWorkList(NewLD.getNode());
7527 AddToWorkList(NewST.getNode());
7528 WorkListRemover DeadNodes(*this);
Jakob Stoklund Olesenbc7d4482012-04-20 22:08:46 +00007529 DAG.ReplaceAllUsesOfValueWith(Value.getValue(1), NewLD.getValue(1));
Evan Cheng31959b12011-02-02 01:06:55 +00007530 ++LdStFP2Int;
7531 return NewST;
7532 }
7533
7534 return SDValue();
7535}
7536
Nadav Rotemc653de62012-10-03 16:11:15 +00007537/// Returns the base pointer and an integer offset from that object.
7538static std::pair<SDValue, int64_t> GetPointerBaseAndOffset(SDValue Ptr) {
7539 if (Ptr->getOpcode() == ISD::ADD && isa<ConstantSDNode>(Ptr->getOperand(1))) {
7540 int64_t Offset = cast<ConstantSDNode>(Ptr->getOperand(1))->getSExtValue();
7541 SDValue Base = Ptr->getOperand(0);
7542 return std::make_pair(Base, Offset);
7543 }
7544
7545 return std::make_pair(Ptr, 0);
7546}
7547
7548/// Holds a pointer to an LSBaseSDNode as well as information on where it
7549/// is located in a sequence of memory operations connected by a chain.
7550struct MemOpLink {
7551 MemOpLink (LSBaseSDNode *N, int64_t Offset, unsigned Seq):
7552 MemNode(N), OffsetFromBase(Offset), SequenceNum(Seq) { }
7553 // Ptr to the mem node.
7554 LSBaseSDNode *MemNode;
7555 // Offset from the base ptr.
7556 int64_t OffsetFromBase;
7557 // What is the sequence number of this mem node.
7558 // Lowest mem operand in the DAG starts at zero.
7559 unsigned SequenceNum;
7560};
7561
7562/// Sorts store nodes in a link according to their offset from a shared
7563// base ptr.
7564struct ConsecutiveMemoryChainSorter {
7565 bool operator()(MemOpLink LHS, MemOpLink RHS) {
7566 return LHS.OffsetFromBase < RHS.OffsetFromBase;
7567 }
7568};
7569
7570bool DAGCombiner::MergeConsecutiveStores(StoreSDNode* St) {
7571 EVT MemVT = St->getMemoryVT();
7572 int64_t ElementSizeBytes = MemVT.getSizeInBits()/8;
7573
7574 // Don't merge vectors into wider inputs.
7575 if (MemVT.isVector() || !MemVT.isSimple())
7576 return false;
7577
7578 // Perform an early exit check. Do not bother looking at stored values that
7579 // are not constants or loads.
7580 SDValue StoredVal = St->getValue();
7581 bool IsLoadSrc = isa<LoadSDNode>(StoredVal);
7582 if (!isa<ConstantSDNode>(StoredVal) && !isa<ConstantFPSDNode>(StoredVal) &&
7583 !IsLoadSrc)
7584 return false;
7585
7586 // Only look at ends of store sequences.
7587 SDValue Chain = SDValue(St, 1);
7588 if (Chain->hasOneUse() && Chain->use_begin()->getOpcode() == ISD::STORE)
7589 return false;
7590
7591 // This holds the base pointer and the offset in bytes from the base pointer.
7592 std::pair<SDValue, int64_t> BasePtr =
7593 GetPointerBaseAndOffset(St->getBasePtr());
7594
7595 // We must have a base and an offset.
7596 if (!BasePtr.first.getNode())
7597 return false;
7598
7599 // Do not handle stores to undef base pointers.
7600 if (BasePtr.first.getOpcode() == ISD::UNDEF)
7601 return false;
7602
Nadav Rotem90e11dc2012-11-29 00:00:08 +00007603 // Save the LoadSDNodes that we find in the chain.
7604 // We need to make sure that these nodes do not interfere with
7605 // any of the store nodes.
7606 SmallVector<LSBaseSDNode*, 8> AliasLoadNodes;
7607
7608 // Save the StoreSDNodes that we find in the chain.
Nadav Rotemc653de62012-10-03 16:11:15 +00007609 SmallVector<MemOpLink, 8> StoreNodes;
Nadav Rotem90e11dc2012-11-29 00:00:08 +00007610
Nadav Rotemc653de62012-10-03 16:11:15 +00007611 // Walk up the chain and look for nodes with offsets from the same
7612 // base pointer. Stop when reaching an instruction with a different kind
7613 // or instruction which has a different base pointer.
7614 unsigned Seq = 0;
7615 StoreSDNode *Index = St;
7616 while (Index) {
7617 // If the chain has more than one use, then we can't reorder the mem ops.
7618 if (Index != St && !SDValue(Index, 1)->hasOneUse())
7619 break;
7620
7621 // Find the base pointer and offset for this memory node.
7622 std::pair<SDValue, int64_t> Ptr =
7623 GetPointerBaseAndOffset(Index->getBasePtr());
7624
7625 // Check that the base pointer is the same as the original one.
7626 if (Ptr.first.getNode() != BasePtr.first.getNode())
7627 break;
7628
7629 // Check that the alignment is the same.
7630 if (Index->getAlignment() != St->getAlignment())
7631 break;
7632
7633 // The memory operands must not be volatile.
7634 if (Index->isVolatile() || Index->isIndexed())
7635 break;
7636
7637 // No truncation.
7638 if (StoreSDNode *St = dyn_cast<StoreSDNode>(Index))
7639 if (St->isTruncatingStore())
7640 break;
7641
7642 // The stored memory type must be the same.
7643 if (Index->getMemoryVT() != MemVT)
7644 break;
7645
7646 // We do not allow unaligned stores because we want to prevent overriding
7647 // stores.
7648 if (Index->getAlignment()*8 != MemVT.getSizeInBits())
7649 break;
7650
7651 // We found a potential memory operand to merge.
7652 StoreNodes.push_back(MemOpLink(Index, Ptr.second, Seq++));
7653
Nadav Rotem90e11dc2012-11-29 00:00:08 +00007654 // Find the next memory operand in the chain. If the next operand in the
7655 // chain is a store then move up and continue the scan with the next
7656 // memory operand. If the next operand is a load save it and use alias
7657 // information to check if it interferes with anything.
7658 SDNode *NextInChain = Index->getChain().getNode();
7659 while (1) {
Nadav Rotemdde785c2012-12-06 17:34:13 +00007660 if (StoreSDNode *STn = dyn_cast<StoreSDNode>(NextInChain)) {
Nadav Rotem90e11dc2012-11-29 00:00:08 +00007661 // We found a store node. Use it for the next iteration.
Nadav Rotemdde785c2012-12-06 17:34:13 +00007662 Index = STn;
Nadav Rotem90e11dc2012-11-29 00:00:08 +00007663 break;
7664 } else if (LoadSDNode *Ldn = dyn_cast<LoadSDNode>(NextInChain)) {
7665 // Save the load node for later. Continue the scan.
7666 AliasLoadNodes.push_back(Ldn);
7667 NextInChain = Ldn->getChain().getNode();
7668 continue;
7669 } else {
7670 Index = NULL;
7671 break;
7672 }
7673 }
Nadav Rotemc653de62012-10-03 16:11:15 +00007674 }
7675
7676 // Check if there is anything to merge.
7677 if (StoreNodes.size() < 2)
7678 return false;
7679
7680 // Sort the memory operands according to their distance from the base pointer.
7681 std::sort(StoreNodes.begin(), StoreNodes.end(),
7682 ConsecutiveMemoryChainSorter());
7683
7684 // Scan the memory operations on the chain and find the first non-consecutive
7685 // store memory address.
7686 unsigned LastConsecutiveStore = 0;
7687 int64_t StartAddress = StoreNodes[0].OffsetFromBase;
Nadav Rotemdde785c2012-12-06 17:34:13 +00007688 for (unsigned i = 0, e = StoreNodes.size(); i < e; ++i) {
7689
7690 // Check that the addresses are consecutive starting from the second
7691 // element in the list of stores.
7692 if (i > 0) {
7693 int64_t CurrAddress = StoreNodes[i].OffsetFromBase;
7694 if (CurrAddress - StartAddress != (ElementSizeBytes * i))
7695 break;
7696 }
Nadav Rotemc653de62012-10-03 16:11:15 +00007697
Nadav Rotem90e11dc2012-11-29 00:00:08 +00007698 bool Alias = false;
7699 // Check if this store interferes with any of the loads that we found.
7700 for (unsigned ld = 0, lde = AliasLoadNodes.size(); ld < lde; ++ld)
7701 if (isAlias(AliasLoadNodes[ld], StoreNodes[i].MemNode)) {
7702 Alias = true;
7703 break;
7704 }
Nadav Rotem90e11dc2012-11-29 00:00:08 +00007705 // We found a load that alias with this store. Stop the sequence.
7706 if (Alias)
7707 break;
7708
Nadav Rotemc653de62012-10-03 16:11:15 +00007709 // Mark this node as useful.
7710 LastConsecutiveStore = i;
7711 }
7712
7713 // The node with the lowest store address.
7714 LSBaseSDNode *FirstInChain = StoreNodes[0].MemNode;
7715
7716 // Store the constants into memory as one consecutive store.
7717 if (!IsLoadSrc) {
Nadav Rotemc653de62012-10-03 16:11:15 +00007718 unsigned LastLegalType = 0;
Nadav Rotemea2c50c2012-10-04 22:35:15 +00007719 unsigned LastLegalVectorType = 0;
7720 bool NonZero = false;
Nadav Rotemc653de62012-10-03 16:11:15 +00007721 for (unsigned i=0; i<LastConsecutiveStore+1; ++i) {
7722 StoreSDNode *St = cast<StoreSDNode>(StoreNodes[i].MemNode);
7723 SDValue StoredVal = St->getValue();
Nadav Rotemea2c50c2012-10-04 22:35:15 +00007724
7725 if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(StoredVal)) {
Benjamin Kramerebd7eab2012-10-05 18:19:44 +00007726 NonZero |= !C->isNullValue();
Nadav Rotemea2c50c2012-10-04 22:35:15 +00007727 } else if (ConstantFPSDNode *C = dyn_cast<ConstantFPSDNode>(StoredVal)) {
Benjamin Kramerebd7eab2012-10-05 18:19:44 +00007728 NonZero |= !C->getConstantFPValue()->isNullValue();
Nadav Rotemea2c50c2012-10-04 22:35:15 +00007729 } else {
7730 // Non constant.
Nadav Rotemc653de62012-10-03 16:11:15 +00007731 break;
Nadav Rotemea2c50c2012-10-04 22:35:15 +00007732 }
Nadav Rotemc653de62012-10-03 16:11:15 +00007733
Nadav Rotemc653de62012-10-03 16:11:15 +00007734 // Find a legal type for the constant store.
7735 unsigned StoreBW = (i+1) * ElementSizeBytes * 8;
7736 EVT StoreTy = EVT::getIntegerVT(*DAG.getContext(), StoreBW);
7737 if (TLI.isTypeLegal(StoreTy))
7738 LastLegalType = i+1;
Nadav Rotemea2c50c2012-10-04 22:35:15 +00007739
7740 // Find a legal type for the vector store.
7741 EVT Ty = EVT::getVectorVT(*DAG.getContext(), MemVT, i+1);
7742 if (TLI.isTypeLegal(Ty))
7743 LastLegalVectorType = i + 1;
Nadav Rotemc653de62012-10-03 16:11:15 +00007744 }
7745
Nadav Rotemea2c50c2012-10-04 22:35:15 +00007746 // We only use vectors if the constant is known to be zero.
7747 if (NonZero)
7748 LastLegalVectorType = 0;
7749
Nadav Rotemc653de62012-10-03 16:11:15 +00007750 // Check if we found a legal integer type to store.
Nadav Rotemea2c50c2012-10-04 22:35:15 +00007751 if (LastLegalType == 0 && LastLegalVectorType == 0)
Nadav Rotemc653de62012-10-03 16:11:15 +00007752 return false;
7753
Nadav Rotemea2c50c2012-10-04 22:35:15 +00007754 bool UseVector = LastLegalVectorType > LastLegalType;
7755 unsigned NumElem = UseVector ? LastLegalVectorType : LastLegalType;
7756
7757 // Make sure we have something to merge.
7758 if (NumElem < 2)
7759 return false;
Nadav Rotemc653de62012-10-03 16:11:15 +00007760
7761 unsigned EarliestNodeUsed = 0;
7762 for (unsigned i=0; i < NumElem; ++i) {
7763 // Find a chain for the new wide-store operand. Notice that some
7764 // of the store nodes that we found may not be selected for inclusion
7765 // in the wide store. The chain we use needs to be the chain of the
7766 // earliest store node which is *used* and replaced by the wide store.
7767 if (StoreNodes[i].SequenceNum > StoreNodes[EarliestNodeUsed].SequenceNum)
7768 EarliestNodeUsed = i;
7769 }
7770
7771 // The earliest Node in the DAG.
7772 LSBaseSDNode *EarliestOp = StoreNodes[EarliestNodeUsed].MemNode;
Nadav Rotemc653de62012-10-03 16:11:15 +00007773 DebugLoc DL = StoreNodes[0].MemNode->getDebugLoc();
Nadav Rotemc653de62012-10-03 16:11:15 +00007774
Nadav Rotemea2c50c2012-10-04 22:35:15 +00007775 SDValue StoredVal;
7776 if (UseVector) {
7777 // Find a legal type for the vector store.
7778 EVT Ty = EVT::getVectorVT(*DAG.getContext(), MemVT, NumElem);
7779 assert(TLI.isTypeLegal(Ty) && "Illegal vector store");
7780 StoredVal = DAG.getConstant(0, Ty);
7781 } else {
7782 unsigned StoreBW = NumElem * ElementSizeBytes * 8;
7783 APInt StoreInt(StoreBW, 0);
7784
7785 // Construct a single integer constant which is made of the smaller
7786 // constant inputs.
7787 bool IsLE = TLI.isLittleEndian();
7788 for (unsigned i = 0; i < NumElem ; ++i) {
7789 unsigned Idx = IsLE ?(NumElem - 1 - i) : i;
7790 StoreSDNode *St = cast<StoreSDNode>(StoreNodes[Idx].MemNode);
7791 SDValue Val = St->getValue();
7792 StoreInt<<=ElementSizeBytes*8;
7793 if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Val)) {
7794 StoreInt|=C->getAPIntValue().zext(StoreBW);
7795 } else if (ConstantFPSDNode *C = dyn_cast<ConstantFPSDNode>(Val)) {
7796 StoreInt|= C->getValueAPF().bitcastToAPInt().zext(StoreBW);
7797 } else {
7798 assert(false && "Invalid constant element type");
7799 }
Nadav Rotemc653de62012-10-03 16:11:15 +00007800 }
Nadav Rotemea2c50c2012-10-04 22:35:15 +00007801
7802 // Create the new Load and Store operations.
7803 EVT StoreTy = EVT::getIntegerVT(*DAG.getContext(), StoreBW);
7804 StoredVal = DAG.getConstant(StoreInt, StoreTy);
Nadav Rotemc653de62012-10-03 16:11:15 +00007805 }
7806
Nadav Rotemea2c50c2012-10-04 22:35:15 +00007807 SDValue NewStore = DAG.getStore(EarliestOp->getChain(), DL, StoredVal,
Nadav Rotemc653de62012-10-03 16:11:15 +00007808 FirstInChain->getBasePtr(),
7809 FirstInChain->getPointerInfo(),
7810 false, false,
7811 FirstInChain->getAlignment());
7812
7813 // Replace the first store with the new store
7814 CombineTo(EarliestOp, NewStore);
7815 // Erase all other stores.
7816 for (unsigned i = 0; i < NumElem ; ++i) {
7817 if (StoreNodes[i].MemNode == EarliestOp)
7818 continue;
7819 StoreSDNode *St = cast<StoreSDNode>(StoreNodes[i].MemNode);
Rafael Espindola8e2b8ae2012-11-14 05:08:56 +00007820 // ReplaceAllUsesWith will replace all uses that existed when it was
7821 // called, but graph optimizations may cause new ones to appear. For
7822 // example, the case in pr14333 looks like
7823 //
7824 // St's chain -> St -> another store -> X
7825 //
7826 // And the only difference from St to the other store is the chain.
7827 // When we change it's chain to be St's chain they become identical,
7828 // get CSEed and the net result is that X is now a use of St.
7829 // Since we know that St is redundant, just iterate.
7830 while (!St->use_empty())
7831 DAG.ReplaceAllUsesWith(SDValue(St, 0), St->getChain());
Nadav Rotemc653de62012-10-03 16:11:15 +00007832 removeFromWorkList(St);
7833 DAG.DeleteNode(St);
7834 }
7835
7836 return true;
7837 }
7838
7839 // Below we handle the case of multiple consecutive stores that
7840 // come from multiple consecutive loads. We merge them into a single
7841 // wide load and a single wide store.
7842
7843 // Look for load nodes which are used by the stored values.
7844 SmallVector<MemOpLink, 8> LoadNodes;
7845
7846 // Find acceptable loads. Loads need to have the same chain (token factor),
7847 // must not be zext, volatile, indexed, and they must be consecutive.
7848 SDValue LdBasePtr;
7849 for (unsigned i=0; i<LastConsecutiveStore+1; ++i) {
7850 StoreSDNode *St = cast<StoreSDNode>(StoreNodes[i].MemNode);
7851 LoadSDNode *Ld = dyn_cast<LoadSDNode>(St->getValue());
7852 if (!Ld) break;
7853
7854 // Loads must only have one use.
7855 if (!Ld->hasNUsesOfValue(1, 0))
7856 break;
7857
7858 // Check that the alignment is the same as the stores.
7859 if (Ld->getAlignment() != St->getAlignment())
7860 break;
7861
7862 // The memory operands must not be volatile.
7863 if (Ld->isVolatile() || Ld->isIndexed())
7864 break;
7865
7866 // We do not accept ext loads.
7867 if (Ld->getExtensionType() != ISD::NON_EXTLOAD)
7868 break;
7869
7870 // The stored memory type must be the same.
7871 if (Ld->getMemoryVT() != MemVT)
7872 break;
7873
7874 std::pair<SDValue, int64_t> LdPtr =
7875 GetPointerBaseAndOffset(Ld->getBasePtr());
7876
7877 // If this is not the first ptr that we check.
7878 if (LdBasePtr.getNode()) {
7879 // The base ptr must be the same.
7880 if (LdPtr.first != LdBasePtr)
7881 break;
7882 } else {
7883 // Check that all other base pointers are the same as this one.
7884 LdBasePtr = LdPtr.first;
7885 }
7886
7887 // We found a potential memory operand to merge.
7888 LoadNodes.push_back(MemOpLink(Ld, LdPtr.second, 0));
7889 }
7890
7891 if (LoadNodes.size() < 2)
7892 return false;
7893
7894 // Scan the memory operations on the chain and find the first non-consecutive
7895 // load memory address. These variables hold the index in the store node
7896 // array.
7897 unsigned LastConsecutiveLoad = 0;
7898 // This variable refers to the size and not index in the array.
7899 unsigned LastLegalVectorType = 0;
7900 unsigned LastLegalIntegerType = 0;
7901 StartAddress = LoadNodes[0].OffsetFromBase;
Nadav Rotem2e7d3812012-10-03 19:30:31 +00007902 SDValue FirstChain = LoadNodes[0].MemNode->getChain();
7903 for (unsigned i = 1; i < LoadNodes.size(); ++i) {
7904 // All loads much share the same chain.
7905 if (LoadNodes[i].MemNode->getChain() != FirstChain)
7906 break;
7907
Nadav Rotemc653de62012-10-03 16:11:15 +00007908 int64_t CurrAddress = LoadNodes[i].OffsetFromBase;
7909 if (CurrAddress - StartAddress != (ElementSizeBytes * i))
7910 break;
7911 LastConsecutiveLoad = i;
7912
7913 // Find a legal type for the vector store.
7914 EVT StoreTy = EVT::getVectorVT(*DAG.getContext(), MemVT, i+1);
7915 if (TLI.isTypeLegal(StoreTy))
7916 LastLegalVectorType = i + 1;
7917
7918 // Find a legal type for the integer store.
7919 unsigned StoreBW = (i+1) * ElementSizeBytes * 8;
7920 StoreTy = EVT::getIntegerVT(*DAG.getContext(), StoreBW);
7921 if (TLI.isTypeLegal(StoreTy))
7922 LastLegalIntegerType = i + 1;
7923 }
7924
7925 // Only use vector types if the vector type is larger than the integer type.
7926 // If they are the same, use integers.
7927 bool UseVectorTy = LastLegalVectorType > LastLegalIntegerType;
7928 unsigned LastLegalType = std::max(LastLegalVectorType, LastLegalIntegerType);
7929
7930 // We add +1 here because the LastXXX variables refer to location while
7931 // the NumElem refers to array/index size.
7932 unsigned NumElem = std::min(LastConsecutiveStore, LastConsecutiveLoad) + 1;
7933 NumElem = std::min(LastLegalType, NumElem);
7934
7935 if (NumElem < 2)
7936 return false;
7937
7938 // The earliest Node in the DAG.
7939 unsigned EarliestNodeUsed = 0;
7940 LSBaseSDNode *EarliestOp = StoreNodes[EarliestNodeUsed].MemNode;
7941 for (unsigned i=1; i<NumElem; ++i) {
7942 // Find a chain for the new wide-store operand. Notice that some
7943 // of the store nodes that we found may not be selected for inclusion
7944 // in the wide store. The chain we use needs to be the chain of the
7945 // earliest store node which is *used* and replaced by the wide store.
7946 if (StoreNodes[i].SequenceNum > StoreNodes[EarliestNodeUsed].SequenceNum)
7947 EarliestNodeUsed = i;
7948 }
7949
7950 // Find if it is better to use vectors or integers to load and store
7951 // to memory.
7952 EVT JointMemOpVT;
7953 if (UseVectorTy) {
7954 JointMemOpVT = EVT::getVectorVT(*DAG.getContext(), MemVT, NumElem);
7955 } else {
7956 unsigned StoreBW = NumElem * ElementSizeBytes * 8;
7957 JointMemOpVT = EVT::getIntegerVT(*DAG.getContext(), StoreBW);
7958 }
7959
7960 DebugLoc LoadDL = LoadNodes[0].MemNode->getDebugLoc();
7961 DebugLoc StoreDL = StoreNodes[0].MemNode->getDebugLoc();
7962
7963 LoadSDNode *FirstLoad = cast<LoadSDNode>(LoadNodes[0].MemNode);
7964 SDValue NewLoad = DAG.getLoad(JointMemOpVT, LoadDL,
7965 FirstLoad->getChain(),
7966 FirstLoad->getBasePtr(),
7967 FirstLoad->getPointerInfo(),
7968 false, false, false,
7969 FirstLoad->getAlignment());
7970
7971 SDValue NewStore = DAG.getStore(EarliestOp->getChain(), StoreDL, NewLoad,
7972 FirstInChain->getBasePtr(),
7973 FirstInChain->getPointerInfo(), false, false,
7974 FirstInChain->getAlignment());
7975
Nadav Rotem2e7d3812012-10-03 19:30:31 +00007976 // Replace one of the loads with the new load.
7977 LoadSDNode *Ld = cast<LoadSDNode>(LoadNodes[0].MemNode);
7978 DAG.ReplaceAllUsesOfValueWith(SDValue(Ld, 1),
7979 SDValue(NewLoad.getNode(), 1));
7980
7981 // Remove the rest of the load chains.
7982 for (unsigned i = 1; i < NumElem ; ++i) {
Nadav Rotemc653de62012-10-03 16:11:15 +00007983 // Replace all chain users of the old load nodes with the chain of the new
7984 // load node.
7985 LoadSDNode *Ld = cast<LoadSDNode>(LoadNodes[i].MemNode);
Nadav Rotem2e7d3812012-10-03 19:30:31 +00007986 DAG.ReplaceAllUsesOfValueWith(SDValue(Ld, 1), Ld->getChain());
7987 }
Nadav Rotemc653de62012-10-03 16:11:15 +00007988
Nadav Rotem2e7d3812012-10-03 19:30:31 +00007989 // Replace the first store with the new store.
7990 CombineTo(EarliestOp, NewStore);
7991 // Erase all other stores.
7992 for (unsigned i = 0; i < NumElem ; ++i) {
Nadav Rotemc653de62012-10-03 16:11:15 +00007993 // Remove all Store nodes.
7994 if (StoreNodes[i].MemNode == EarliestOp)
7995 continue;
7996 StoreSDNode *St = cast<StoreSDNode>(StoreNodes[i].MemNode);
7997 DAG.ReplaceAllUsesOfValueWith(SDValue(St, 0), St->getChain());
7998 removeFromWorkList(St);
7999 DAG.DeleteNode(St);
8000 }
8001
8002 return true;
8003}
8004
Dan Gohman475871a2008-07-27 21:46:04 +00008005SDValue DAGCombiner::visitSTORE(SDNode *N) {
Evan Cheng8b2794a2006-10-13 21:14:26 +00008006 StoreSDNode *ST = cast<StoreSDNode>(N);
Dan Gohman475871a2008-07-27 21:46:04 +00008007 SDValue Chain = ST->getChain();
8008 SDValue Value = ST->getValue();
8009 SDValue Ptr = ST->getBasePtr();
Scott Michelfdc40a02009-02-17 22:15:04 +00008010
Evan Cheng59d5b682007-05-07 21:27:48 +00008011 // If this is a store of a bit convert, store the input value if the
Evan Cheng2c4f9432007-05-09 21:49:47 +00008012 // resultant store does not need a higher alignment than the original.
Wesley Peckbf17cfa2010-11-23 03:31:01 +00008013 if (Value.getOpcode() == ISD::BITCAST && !ST->isTruncatingStore() &&
Chris Lattnerddf89562008-01-17 19:59:44 +00008014 ST->isUnindexed()) {
Dan Gohman1ba519b2009-02-20 23:29:13 +00008015 unsigned OrigAlign = ST->getAlignment();
Owen Andersone50ed302009-08-10 22:56:29 +00008016 EVT SVT = Value.getOperand(0).getValueType();
Micah Villmow3574eca2012-10-08 16:38:25 +00008017 unsigned Align = TLI.getDataLayout()->
Owen Anderson23b9b192009-08-12 00:36:31 +00008018 getABITypeAlignment(SVT.getTypeForEVT(*DAG.getContext()));
Duncan Sandsd4b9c172008-06-13 19:07:40 +00008019 if (Align <= OrigAlign &&
Duncan Sands25cf2272008-11-24 14:53:14 +00008020 ((!LegalOperations && !ST->isVolatile()) ||
Dan Gohmanf560ffa2009-01-28 17:46:25 +00008021 TLI.isOperationLegalOrCustom(ISD::STORE, SVT)))
Bill Wendlingc144a572009-01-30 23:36:47 +00008022 return DAG.getStore(Chain, N->getDebugLoc(), Value.getOperand(0),
Chris Lattner6229d0a2010-09-21 18:41:36 +00008023 Ptr, ST->getPointerInfo(), ST->isVolatile(),
David Greene1e559442010-02-15 17:00:31 +00008024 ST->isNonTemporal(), OrigAlign);
Jim Laskey279f0532006-09-25 16:29:54 +00008025 }
Owen Andersona34d9362011-04-14 17:30:49 +00008026
Chris Lattnerb3452ea2011-04-09 02:32:02 +00008027 // Turn 'store undef, Ptr' -> nothing.
8028 if (Value.getOpcode() == ISD::UNDEF && ST->isUnindexed())
8029 return Chain;
Duncan Sandsd4b9c172008-06-13 19:07:40 +00008030
Nate Begeman2cbba892006-12-11 02:23:46 +00008031 // Turn 'store float 1.0, Ptr' -> 'store int 0x12345678, Ptr'
Nate Begeman2cbba892006-12-11 02:23:46 +00008032 if (ConstantFPSDNode *CFP = dyn_cast<ConstantFPSDNode>(Value)) {
Duncan Sandsd4b9c172008-06-13 19:07:40 +00008033 // NOTE: If the original store is volatile, this transform must not increase
8034 // the number of stores. For example, on x86-32 an f64 can be stored in one
8035 // processor operation but an i64 (which is not legal) requires two. So the
8036 // transform should not be done in this case.
Evan Cheng25ece662006-12-11 17:25:19 +00008037 if (Value.getOpcode() != ISD::TargetConstantFP) {
Dan Gohman475871a2008-07-27 21:46:04 +00008038 SDValue Tmp;
Owen Anderson825b72b2009-08-11 20:47:22 +00008039 switch (CFP->getValueType(0).getSimpleVT().SimpleTy) {
Torok Edwinc23197a2009-07-14 16:55:14 +00008040 default: llvm_unreachable("Unknown FP type");
Pete Cooper438c0402012-06-21 18:00:39 +00008041 case MVT::f16: // We don't do this for these yet.
8042 case MVT::f80:
Owen Anderson825b72b2009-08-11 20:47:22 +00008043 case MVT::f128:
8044 case MVT::ppcf128:
Dale Johannesenc7b21d52007-09-18 18:36:59 +00008045 break;
Owen Anderson825b72b2009-08-11 20:47:22 +00008046 case MVT::f32:
Chris Lattner2392ae72010-04-15 04:48:01 +00008047 if ((isTypeLegal(MVT::i32) && !LegalOperations && !ST->isVolatile()) ||
Owen Anderson825b72b2009-08-11 20:47:22 +00008048 TLI.isOperationLegalOrCustom(ISD::STORE, MVT::i32)) {
Dale Johannesen9d5f4562007-09-12 03:30:33 +00008049 Tmp = DAG.getConstant((uint32_t)CFP->getValueAPF().
Owen Anderson825b72b2009-08-11 20:47:22 +00008050 bitcastToAPInt().getZExtValue(), MVT::i32);
Bill Wendlingc144a572009-01-30 23:36:47 +00008051 return DAG.getStore(Chain, N->getDebugLoc(), Tmp,
Chris Lattner6229d0a2010-09-21 18:41:36 +00008052 Ptr, ST->getPointerInfo(), ST->isVolatile(),
David Greene1e559442010-02-15 17:00:31 +00008053 ST->isNonTemporal(), ST->getAlignment());
Chris Lattner62be1a72006-12-12 04:16:14 +00008054 }
8055 break;
Owen Anderson825b72b2009-08-11 20:47:22 +00008056 case MVT::f64:
Chris Lattner2392ae72010-04-15 04:48:01 +00008057 if ((TLI.isTypeLegal(MVT::i64) && !LegalOperations &&
Dan Gohmanf560ffa2009-01-28 17:46:25 +00008058 !ST->isVolatile()) ||
Owen Anderson825b72b2009-08-11 20:47:22 +00008059 TLI.isOperationLegalOrCustom(ISD::STORE, MVT::i64)) {
Dale Johannesen7111b022008-10-09 18:53:47 +00008060 Tmp = DAG.getConstant(CFP->getValueAPF().bitcastToAPInt().
Owen Anderson825b72b2009-08-11 20:47:22 +00008061 getZExtValue(), MVT::i64);
Bill Wendlingc144a572009-01-30 23:36:47 +00008062 return DAG.getStore(Chain, N->getDebugLoc(), Tmp,
Chris Lattner6229d0a2010-09-21 18:41:36 +00008063 Ptr, ST->getPointerInfo(), ST->isVolatile(),
David Greene1e559442010-02-15 17:00:31 +00008064 ST->isNonTemporal(), ST->getAlignment());
Chris Lattnerb3452ea2011-04-09 02:32:02 +00008065 }
Owen Andersona34d9362011-04-14 17:30:49 +00008066
Chris Lattnerb3452ea2011-04-09 02:32:02 +00008067 if (!ST->isVolatile() &&
8068 TLI.isOperationLegalOrCustom(ISD::STORE, MVT::i32)) {
Duncan Sandsdc846502007-10-28 12:59:45 +00008069 // Many FP stores are not made apparent until after legalize, e.g. for
Chris Lattner62be1a72006-12-12 04:16:14 +00008070 // argument passing. Since this is so common, custom legalize the
8071 // 64-bit integer store into two 32-bit stores.
Dale Johannesen7111b022008-10-09 18:53:47 +00008072 uint64_t Val = CFP->getValueAPF().bitcastToAPInt().getZExtValue();
Owen Anderson825b72b2009-08-11 20:47:22 +00008073 SDValue Lo = DAG.getConstant(Val & 0xFFFFFFFF, MVT::i32);
8074 SDValue Hi = DAG.getConstant(Val >> 32, MVT::i32);
Duncan Sands0753fc12008-02-11 10:37:04 +00008075 if (TLI.isBigEndian()) std::swap(Lo, Hi);
Chris Lattner62be1a72006-12-12 04:16:14 +00008076
Dan Gohmand6fd1bc2007-07-09 22:18:38 +00008077 unsigned Alignment = ST->getAlignment();
8078 bool isVolatile = ST->isVolatile();
David Greene1e559442010-02-15 17:00:31 +00008079 bool isNonTemporal = ST->isNonTemporal();
Dan Gohmand6fd1bc2007-07-09 22:18:38 +00008080
Bill Wendlingc144a572009-01-30 23:36:47 +00008081 SDValue St0 = DAG.getStore(Chain, ST->getDebugLoc(), Lo,
Chris Lattner6229d0a2010-09-21 18:41:36 +00008082 Ptr, ST->getPointerInfo(),
David Greene1e559442010-02-15 17:00:31 +00008083 isVolatile, isNonTemporal,
8084 ST->getAlignment());
Bill Wendlingc144a572009-01-30 23:36:47 +00008085 Ptr = DAG.getNode(ISD::ADD, N->getDebugLoc(), Ptr.getValueType(), Ptr,
Chris Lattner62be1a72006-12-12 04:16:14 +00008086 DAG.getConstant(4, Ptr.getValueType()));
Duncan Sandsdc846502007-10-28 12:59:45 +00008087 Alignment = MinAlign(Alignment, 4U);
Bill Wendlingc144a572009-01-30 23:36:47 +00008088 SDValue St1 = DAG.getStore(Chain, ST->getDebugLoc(), Hi,
Chris Lattner6229d0a2010-09-21 18:41:36 +00008089 Ptr, ST->getPointerInfo().getWithOffset(4),
8090 isVolatile, isNonTemporal,
David Greene1e559442010-02-15 17:00:31 +00008091 Alignment);
Owen Anderson825b72b2009-08-11 20:47:22 +00008092 return DAG.getNode(ISD::TokenFactor, N->getDebugLoc(), MVT::Other,
Bill Wendlingc144a572009-01-30 23:36:47 +00008093 St0, St1);
Chris Lattner62be1a72006-12-12 04:16:14 +00008094 }
Bill Wendlingc144a572009-01-30 23:36:47 +00008095
Chris Lattner62be1a72006-12-12 04:16:14 +00008096 break;
Evan Cheng25ece662006-12-11 17:25:19 +00008097 }
Nate Begeman2cbba892006-12-11 02:23:46 +00008098 }
Nate Begeman2cbba892006-12-11 02:23:46 +00008099 }
8100
Evan Cheng255f20f2010-04-01 06:04:33 +00008101 // Try to infer better alignment information than the store already has.
8102 if (OptLevel != CodeGenOpt::None && ST->isUnindexed()) {
Evan Chenged1c0c72011-11-28 22:37:34 +00008103 if (unsigned Align = DAG.InferPtrAlignment(Ptr)) {
8104 if (Align > ST->getAlignment())
8105 return DAG.getTruncStore(Chain, N->getDebugLoc(), Value,
8106 Ptr, ST->getPointerInfo(), ST->getMemoryVT(),
8107 ST->isVolatile(), ST->isNonTemporal(), Align);
Evan Cheng255f20f2010-04-01 06:04:33 +00008108 }
8109 }
8110
Evan Cheng31959b12011-02-02 01:06:55 +00008111 // Try transforming a pair floating point load / store ops to integer
8112 // load / store ops.
8113 SDValue NewST = TransformFPLoadStorePair(N);
8114 if (NewST.getNode())
8115 return NewST;
8116
Scott Michelfdc40a02009-02-17 22:15:04 +00008117 if (CombinerAA) {
Jim Laskey279f0532006-09-25 16:29:54 +00008118 // Walk up chain skipping non-aliasing memory nodes.
Dan Gohman475871a2008-07-27 21:46:04 +00008119 SDValue BetterChain = FindBetterChain(N, Chain);
Scott Michelfdc40a02009-02-17 22:15:04 +00008120
Jim Laskey6ff23e52006-10-04 16:53:27 +00008121 // If there is a better chain.
Jim Laskey279f0532006-09-25 16:29:54 +00008122 if (Chain != BetterChain) {
Dan Gohman475871a2008-07-27 21:46:04 +00008123 SDValue ReplStore;
Nate Begemanb6aef5c2009-09-15 00:18:30 +00008124
8125 // Replace the chain to avoid dependency.
Jim Laskeyd4edf2c2006-10-14 12:14:27 +00008126 if (ST->isTruncatingStore()) {
Bill Wendlingc144a572009-01-30 23:36:47 +00008127 ReplStore = DAG.getTruncStore(BetterChain, N->getDebugLoc(), Value, Ptr,
Chris Lattnerda2d8e12010-09-21 17:42:31 +00008128 ST->getPointerInfo(),
David Greene1e559442010-02-15 17:00:31 +00008129 ST->getMemoryVT(), ST->isVolatile(),
8130 ST->isNonTemporal(), ST->getAlignment());
Jim Laskeyd4edf2c2006-10-14 12:14:27 +00008131 } else {
Bill Wendlingc144a572009-01-30 23:36:47 +00008132 ReplStore = DAG.getStore(BetterChain, N->getDebugLoc(), Value, Ptr,
Chris Lattner6229d0a2010-09-21 18:41:36 +00008133 ST->getPointerInfo(),
David Greene1e559442010-02-15 17:00:31 +00008134 ST->isVolatile(), ST->isNonTemporal(),
8135 ST->getAlignment());
Jim Laskeyd4edf2c2006-10-14 12:14:27 +00008136 }
Scott Michelfdc40a02009-02-17 22:15:04 +00008137
Jim Laskey279f0532006-09-25 16:29:54 +00008138 // Create token to keep both nodes around.
Bill Wendlingc144a572009-01-30 23:36:47 +00008139 SDValue Token = DAG.getNode(ISD::TokenFactor, N->getDebugLoc(),
Owen Anderson825b72b2009-08-11 20:47:22 +00008140 MVT::Other, Chain, ReplStore);
Bill Wendlingc144a572009-01-30 23:36:47 +00008141
Nate Begemanb6aef5c2009-09-15 00:18:30 +00008142 // Make sure the new and old chains are cleaned up.
8143 AddToWorkList(Token.getNode());
8144
Jim Laskey274062c2006-10-13 23:32:28 +00008145 // Don't add users to work list.
8146 return CombineTo(N, Token, false);
Jim Laskey279f0532006-09-25 16:29:54 +00008147 }
Jim Laskeyd1aed7a2006-09-21 16:28:59 +00008148 }
Scott Michelfdc40a02009-02-17 22:15:04 +00008149
Evan Cheng33dbedc2006-11-05 09:31:14 +00008150 // Try transforming N to an indexed store.
Evan Chengbbd6f6e2006-11-07 09:03:05 +00008151 if (CombineToPreIndexedLoadStore(N) || CombineToPostIndexedLoadStore(N))
Dan Gohman475871a2008-07-27 21:46:04 +00008152 return SDValue(N, 0);
Evan Cheng33dbedc2006-11-05 09:31:14 +00008153
Chris Lattner3c872852007-12-29 06:26:16 +00008154 // FIXME: is there such a thing as a truncating indexed store?
Chris Lattnerddf89562008-01-17 19:59:44 +00008155 if (ST->isTruncatingStore() && ST->isUnindexed() &&
Nadav Rotembaff46f2011-06-15 11:19:12 +00008156 Value.getValueType().isInteger()) {
Chris Lattner2b4c2792007-10-13 06:35:54 +00008157 // See if we can simplify the input to this truncstore with knowledge that
8158 // only the low bits are being used. For example:
8159 // "truncstore (or (shl x, 8), y), i8" -> "truncstore y, i8"
Scott Michelfdc40a02009-02-17 22:15:04 +00008160 SDValue Shorter =
Dan Gohman2e68b6f2008-02-25 21:11:39 +00008161 GetDemandedBits(Value,
Nadav Rotembaff46f2011-06-15 11:19:12 +00008162 APInt::getLowBitsSet(
8163 Value.getValueType().getScalarType().getSizeInBits(),
8164 ST->getMemoryVT().getScalarType().getSizeInBits()));
Gabor Greifba36cb52008-08-28 21:40:38 +00008165 AddToWorkList(Value.getNode());
8166 if (Shorter.getNode())
Bill Wendlingc144a572009-01-30 23:36:47 +00008167 return DAG.getTruncStore(Chain, N->getDebugLoc(), Shorter,
Chris Lattnerda2d8e12010-09-21 17:42:31 +00008168 Ptr, ST->getPointerInfo(), ST->getMemoryVT(),
David Greene1e559442010-02-15 17:00:31 +00008169 ST->isVolatile(), ST->isNonTemporal(),
8170 ST->getAlignment());
Scott Michelfdc40a02009-02-17 22:15:04 +00008171
Chris Lattnere33544c2007-10-13 06:58:48 +00008172 // Otherwise, see if we can simplify the operation with
8173 // SimplifyDemandedBits, which only works if the value has a single use.
Dan Gohman7b8d4a92008-02-27 00:25:32 +00008174 if (SimplifyDemandedBits(Value,
Eric Christopher503a64d2010-12-09 04:48:06 +00008175 APInt::getLowBitsSet(
8176 Value.getValueType().getScalarType().getSizeInBits(),
8177 ST->getMemoryVT().getScalarType().getSizeInBits())))
Dan Gohman475871a2008-07-27 21:46:04 +00008178 return SDValue(N, 0);
Chris Lattner2b4c2792007-10-13 06:35:54 +00008179 }
Scott Michelfdc40a02009-02-17 22:15:04 +00008180
Chris Lattner3c872852007-12-29 06:26:16 +00008181 // If this is a load followed by a store to the same location, then the store
8182 // is dead/noop.
8183 if (LoadSDNode *Ld = dyn_cast<LoadSDNode>(Value)) {
Dan Gohmanb625f2f2008-01-30 00:15:11 +00008184 if (Ld->getBasePtr() == Ptr && ST->getMemoryVT() == Ld->getMemoryVT() &&
Chris Lattnerddf89562008-01-17 19:59:44 +00008185 ST->isUnindexed() && !ST->isVolatile() &&
Chris Lattner07649d92008-01-08 23:08:06 +00008186 // There can't be any side effects between the load and store, such as
8187 // a call or store.
Dan Gohman475871a2008-07-27 21:46:04 +00008188 Chain.reachesChainWithoutSideEffects(SDValue(Ld, 1))) {
Chris Lattner3c872852007-12-29 06:26:16 +00008189 // The store is dead, remove it.
8190 return Chain;
8191 }
8192 }
Duncan Sandsd4b9c172008-06-13 19:07:40 +00008193
Chris Lattnerddf89562008-01-17 19:59:44 +00008194 // If this is an FP_ROUND or TRUNC followed by a store, fold this into a
8195 // truncating store. We can do this even if this is already a truncstore.
8196 if ((Value.getOpcode() == ISD::FP_ROUND || Value.getOpcode() == ISD::TRUNCATE)
Gabor Greifba36cb52008-08-28 21:40:38 +00008197 && Value.getNode()->hasOneUse() && ST->isUnindexed() &&
Chris Lattnerddf89562008-01-17 19:59:44 +00008198 TLI.isTruncStoreLegal(Value.getOperand(0).getValueType(),
Dan Gohmanb625f2f2008-01-30 00:15:11 +00008199 ST->getMemoryVT())) {
Bill Wendlingc144a572009-01-30 23:36:47 +00008200 return DAG.getTruncStore(Chain, N->getDebugLoc(), Value.getOperand(0),
Chris Lattnerda2d8e12010-09-21 17:42:31 +00008201 Ptr, ST->getPointerInfo(), ST->getMemoryVT(),
David Greene1e559442010-02-15 17:00:31 +00008202 ST->isVolatile(), ST->isNonTemporal(),
8203 ST->getAlignment());
Chris Lattnerddf89562008-01-17 19:59:44 +00008204 }
Duncan Sandsd4b9c172008-06-13 19:07:40 +00008205
Nadav Rotemc653de62012-10-03 16:11:15 +00008206 // Only perform this optimization before the types are legal, because we
Nadav Rotemea2c50c2012-10-04 22:35:15 +00008207 // don't want to perform this optimization on every DAGCombine invocation.
Nadav Rotema569a802012-12-02 17:14:09 +00008208 if (!LegalTypes) {
8209 bool EverChanged = false;
8210
8211 do {
8212 // There can be multiple store sequences on the same chain.
8213 // Keep trying to merge store sequences until we are unable to do so
8214 // or until we merge the last store on the chain.
8215 bool Changed = MergeConsecutiveStores(ST);
8216 EverChanged |= Changed;
8217 if (!Changed) break;
8218 } while (ST->getOpcode() != ISD::DELETED_NODE);
8219
8220 if (EverChanged)
8221 return SDValue(N, 0);
8222 }
Nadav Rotemc653de62012-10-03 16:11:15 +00008223
Evan Cheng8b944d32009-05-28 00:35:15 +00008224 return ReduceLoadOpStoreWidth(N);
Chris Lattner87514ca2005-10-10 22:31:19 +00008225}
8226
Dan Gohman475871a2008-07-27 21:46:04 +00008227SDValue DAGCombiner::visitINSERT_VECTOR_ELT(SDNode *N) {
8228 SDValue InVec = N->getOperand(0);
8229 SDValue InVal = N->getOperand(1);
8230 SDValue EltNo = N->getOperand(2);
Eli Friedman9db817f2011-09-09 21:04:06 +00008231 DebugLoc dl = N->getDebugLoc();
Scott Michelfdc40a02009-02-17 22:15:04 +00008232
Bob Wilson492fd452010-05-19 23:42:58 +00008233 // If the inserted element is an UNDEF, just use the input vector.
8234 if (InVal.getOpcode() == ISD::UNDEF)
8235 return InVec;
8236
Nadav Rotem609d54e2011-02-12 14:40:33 +00008237 EVT VT = InVec.getValueType();
8238
Owen Anderson95771af2011-02-25 21:41:48 +00008239 // If we can't generate a legal BUILD_VECTOR, exit
Nadav Rotem609d54e2011-02-12 14:40:33 +00008240 if (LegalOperations && !TLI.isOperationLegal(ISD::BUILD_VECTOR, VT))
8241 return SDValue();
8242
Eli Friedman9db817f2011-09-09 21:04:06 +00008243 // Check that we know which element is being inserted
8244 if (!isa<ConstantSDNode>(EltNo))
8245 return SDValue();
8246 unsigned Elt = cast<ConstantSDNode>(EltNo)->getZExtValue();
Scott Michelfdc40a02009-02-17 22:15:04 +00008247
Eli Friedman9db817f2011-09-09 21:04:06 +00008248 // Check that the operand is a BUILD_VECTOR (or UNDEF, which can essentially
8249 // be converted to a BUILD_VECTOR). Fill in the Ops vector with the
8250 // vector elements.
8251 SmallVector<SDValue, 8> Ops;
8252 if (InVec.getOpcode() == ISD::BUILD_VECTOR) {
8253 Ops.append(InVec.getNode()->op_begin(),
8254 InVec.getNode()->op_end());
8255 } else if (InVec.getOpcode() == ISD::UNDEF) {
8256 unsigned NElts = VT.getVectorNumElements();
8257 Ops.append(NElts, DAG.getUNDEF(InVal.getValueType()));
8258 } else {
8259 return SDValue();
Nate Begeman9008ca62009-04-27 18:41:29 +00008260 }
Eli Friedman9db817f2011-09-09 21:04:06 +00008261
8262 // Insert the element
8263 if (Elt < Ops.size()) {
8264 // All the operands of BUILD_VECTOR must have the same type;
8265 // we enforce that here.
8266 EVT OpVT = Ops[0].getValueType();
8267 if (InVal.getValueType() != OpVT)
8268 InVal = OpVT.bitsGT(InVal.getValueType()) ?
8269 DAG.getNode(ISD::ANY_EXTEND, dl, OpVT, InVal) :
8270 DAG.getNode(ISD::TRUNCATE, dl, OpVT, InVal);
8271 Ops[Elt] = InVal;
8272 }
8273
8274 // Return the new vector
8275 return DAG.getNode(ISD::BUILD_VECTOR, dl,
8276 VT, &Ops[0], Ops.size());
Chris Lattnerca242442006-03-19 01:27:56 +00008277}
8278
Dan Gohman475871a2008-07-27 21:46:04 +00008279SDValue DAGCombiner::visitEXTRACT_VECTOR_ELT(SDNode *N) {
Mon P Wang7ac9cdf2009-01-17 00:07:25 +00008280 // (vextract (scalar_to_vector val, 0) -> val
8281 SDValue InVec = N->getOperand(0);
Nadav Rotemba05c912012-01-17 21:44:01 +00008282 EVT VT = InVec.getValueType();
8283 EVT NVT = N->getValueType(0);
Mon P Wang7ac9cdf2009-01-17 00:07:25 +00008284
Duncan Sandsc356f332011-05-09 08:03:33 +00008285 if (InVec.getOpcode() == ISD::SCALAR_TO_VECTOR) {
8286 // Check if the result type doesn't match the inserted element type. A
8287 // SCALAR_TO_VECTOR may truncate the inserted element and the
8288 // EXTRACT_VECTOR_ELT may widen the extracted vector.
8289 SDValue InOp = InVec.getOperand(0);
Duncan Sandsc356f332011-05-09 08:03:33 +00008290 if (InOp.getValueType() != NVT) {
8291 assert(InOp.getValueType().isInteger() && NVT.isInteger());
8292 return DAG.getSExtOrTrunc(InOp, InVec.getDebugLoc(), NVT);
8293 }
8294 return InOp;
8295 }
Evan Cheng77f0b7a2008-05-13 08:35:03 +00008296
Nadav Rotemba05c912012-01-17 21:44:01 +00008297 SDValue EltNo = N->getOperand(1);
8298 bool ConstEltNo = isa<ConstantSDNode>(EltNo);
8299
8300 // Transform: (EXTRACT_VECTOR_ELT( VECTOR_SHUFFLE )) -> EXTRACT_VECTOR_ELT.
8301 // We only perform this optimization before the op legalization phase because
Nadav Rotem6dfabb62012-09-20 08:53:31 +00008302 // we may introduce new vector instructions which are not backed by TD
8303 // patterns. For example on AVX, extracting elements from a wide vector
8304 // without using extract_subvector.
Nadav Rotemba05c912012-01-17 21:44:01 +00008305 if (InVec.getOpcode() == ISD::VECTOR_SHUFFLE
8306 && ConstEltNo && !LegalOperations) {
8307 int Elt = cast<ConstantSDNode>(EltNo)->getZExtValue();
8308 int NumElem = VT.getVectorNumElements();
8309 ShuffleVectorSDNode *SVOp = cast<ShuffleVectorSDNode>(InVec);
8310 // Find the new index to extract from.
8311 int OrigElt = SVOp->getMaskElt(Elt);
8312
8313 // Extracting an undef index is undef.
8314 if (OrigElt == -1)
8315 return DAG.getUNDEF(NVT);
8316
8317 // Select the right vector half to extract from.
8318 if (OrigElt < NumElem) {
8319 InVec = InVec->getOperand(0);
8320 } else {
8321 InVec = InVec->getOperand(1);
8322 OrigElt -= NumElem;
8323 }
8324
Jim Grosbacha249f7d2012-05-08 20:56:07 +00008325 EVT IndexTy = N->getOperand(1).getValueType();
Nadav Rotemba05c912012-01-17 21:44:01 +00008326 return DAG.getNode(ISD::EXTRACT_VECTOR_ELT, N->getDebugLoc(), NVT,
Jim Grosbacha249f7d2012-05-08 20:56:07 +00008327 InVec, DAG.getConstant(OrigElt, IndexTy));
Nadav Rotemba05c912012-01-17 21:44:01 +00008328 }
8329
Evan Cheng77f0b7a2008-05-13 08:35:03 +00008330 // Perform only after legalization to ensure build_vector / vector_shuffle
8331 // optimizations have already been done.
Duncan Sands25cf2272008-11-24 14:53:14 +00008332 if (!LegalOperations) return SDValue();
Evan Cheng77f0b7a2008-05-13 08:35:03 +00008333
Mon P Wang7ac9cdf2009-01-17 00:07:25 +00008334 // (vextract (v4f32 load $addr), c) -> (f32 load $addr+c*size)
8335 // (vextract (v4f32 s2v (f32 load $addr)), c) -> (f32 load $addr+c*size)
8336 // (vextract (v4f32 shuffle (load $addr), <1,u,u,u>), 0) -> (f32 load $addr)
Evan Cheng513da432007-10-06 08:19:55 +00008337
Nadav Rotemba05c912012-01-17 21:44:01 +00008338 if (ConstEltNo) {
Eric Christophercaebdd42010-11-03 09:36:40 +00008339 int Elt = cast<ConstantSDNode>(EltNo)->getZExtValue();
Evan Cheng513da432007-10-06 08:19:55 +00008340 bool NewLoad = false;
Mon P Wanga60b5232008-12-11 00:26:16 +00008341 bool BCNumEltsChanged = false;
Owen Andersone50ed302009-08-10 22:56:29 +00008342 EVT ExtVT = VT.getVectorElementType();
8343 EVT LVT = ExtVT;
Bill Wendlingc144a572009-01-30 23:36:47 +00008344
Evan Cheng84387ea2012-03-13 22:00:52 +00008345 // If the result of load has to be truncated, then it's not necessarily
8346 // profitable.
Evan Chenga03d3662012-03-13 22:16:11 +00008347 if (NVT.bitsLT(LVT) && !TLI.isTruncateFree(LVT, NVT))
Evan Cheng84387ea2012-03-13 22:00:52 +00008348 return SDValue();
8349
Wesley Peckbf17cfa2010-11-23 03:31:01 +00008350 if (InVec.getOpcode() == ISD::BITCAST) {
Eli Friedmand6e25602011-12-26 22:49:32 +00008351 // Don't duplicate a load with other uses.
8352 if (!InVec.hasOneUse())
8353 return SDValue();
8354
Owen Andersone50ed302009-08-10 22:56:29 +00008355 EVT BCVT = InVec.getOperand(0).getValueType();
8356 if (!BCVT.isVector() || ExtVT.bitsGT(BCVT.getVectorElementType()))
Dan Gohman475871a2008-07-27 21:46:04 +00008357 return SDValue();
Mon P Wanga60b5232008-12-11 00:26:16 +00008358 if (VT.getVectorNumElements() != BCVT.getVectorNumElements())
8359 BCNumEltsChanged = true;
Evan Cheng77f0b7a2008-05-13 08:35:03 +00008360 InVec = InVec.getOperand(0);
Owen Andersone50ed302009-08-10 22:56:29 +00008361 ExtVT = BCVT.getVectorElementType();
Evan Cheng77f0b7a2008-05-13 08:35:03 +00008362 NewLoad = true;
8363 }
Evan Cheng513da432007-10-06 08:19:55 +00008364
Evan Cheng77f0b7a2008-05-13 08:35:03 +00008365 LoadSDNode *LN0 = NULL;
Nate Begeman5a5ca152009-04-29 05:20:52 +00008366 const ShuffleVectorSDNode *SVN = NULL;
Bill Wendlingc144a572009-01-30 23:36:47 +00008367 if (ISD::isNormalLoad(InVec.getNode())) {
Evan Cheng77f0b7a2008-05-13 08:35:03 +00008368 LN0 = cast<LoadSDNode>(InVec);
Bill Wendlingc144a572009-01-30 23:36:47 +00008369 } else if (InVec.getOpcode() == ISD::SCALAR_TO_VECTOR &&
Owen Andersone50ed302009-08-10 22:56:29 +00008370 InVec.getOperand(0).getValueType() == ExtVT &&
Bill Wendlingc144a572009-01-30 23:36:47 +00008371 ISD::isNormalLoad(InVec.getOperand(0).getNode())) {
Eli Friedmand6e25602011-12-26 22:49:32 +00008372 // Don't duplicate a load with other uses.
8373 if (!InVec.hasOneUse())
8374 return SDValue();
8375
Evan Cheng77f0b7a2008-05-13 08:35:03 +00008376 LN0 = cast<LoadSDNode>(InVec.getOperand(0));
Nate Begeman5a5ca152009-04-29 05:20:52 +00008377 } else if ((SVN = dyn_cast<ShuffleVectorSDNode>(InVec))) {
Evan Cheng77f0b7a2008-05-13 08:35:03 +00008378 // (vextract (vector_shuffle (load $addr), v2, <1, u, u, u>), 1)
8379 // =>
8380 // (load $addr+1*size)
Scott Michelfdc40a02009-02-17 22:15:04 +00008381
Eli Friedmand6e25602011-12-26 22:49:32 +00008382 // Don't duplicate a load with other uses.
8383 if (!InVec.hasOneUse())
8384 return SDValue();
8385
Mon P Wanga60b5232008-12-11 00:26:16 +00008386 // If the bit convert changed the number of elements, it is unsafe
8387 // to examine the mask.
8388 if (BCNumEltsChanged)
8389 return SDValue();
Nate Begeman5a5ca152009-04-29 05:20:52 +00008390
8391 // Select the input vector, guarding against out of range extract vector.
8392 unsigned NumElems = VT.getVectorNumElements();
Eric Christophercaebdd42010-11-03 09:36:40 +00008393 int Idx = (Elt > (int)NumElems) ? -1 : SVN->getMaskElt(Elt);
Nate Begeman5a5ca152009-04-29 05:20:52 +00008394 InVec = (Idx < (int)NumElems) ? InVec.getOperand(0) : InVec.getOperand(1);
8395
Eli Friedmand6e25602011-12-26 22:49:32 +00008396 if (InVec.getOpcode() == ISD::BITCAST) {
8397 // Don't duplicate a load with other uses.
8398 if (!InVec.hasOneUse())
8399 return SDValue();
8400
Evan Cheng77f0b7a2008-05-13 08:35:03 +00008401 InVec = InVec.getOperand(0);
Eli Friedmand6e25602011-12-26 22:49:32 +00008402 }
Gabor Greifba36cb52008-08-28 21:40:38 +00008403 if (ISD::isNormalLoad(InVec.getNode())) {
Evan Cheng77f0b7a2008-05-13 08:35:03 +00008404 LN0 = cast<LoadSDNode>(InVec);
Ted Kremenekd0e88f32010-04-08 18:49:30 +00008405 Elt = (Idx < (int)NumElems) ? Idx : Idx - (int)NumElems;
Evan Cheng513da432007-10-06 08:19:55 +00008406 }
8407 }
Bill Wendlingc144a572009-01-30 23:36:47 +00008408
Eli Friedmand6e25602011-12-26 22:49:32 +00008409 // Make sure we found a non-volatile load and the extractelement is
8410 // the only use.
Nadav Rotem42febc62011-05-11 14:40:50 +00008411 if (!LN0 || !LN0->hasNUsesOfValue(1,0) || LN0->isVolatile())
Dan Gohman475871a2008-07-27 21:46:04 +00008412 return SDValue();
Evan Cheng77f0b7a2008-05-13 08:35:03 +00008413
Eric Christopherd81f17a2010-11-03 20:44:42 +00008414 // If Idx was -1 above, Elt is going to be -1, so just return undef.
8415 if (Elt == -1)
Eli Friedmaned4b4272011-07-25 22:25:42 +00008416 return DAG.getUNDEF(LVT);
Eric Christopherd81f17a2010-11-03 20:44:42 +00008417
Evan Cheng77f0b7a2008-05-13 08:35:03 +00008418 unsigned Align = LN0->getAlignment();
8419 if (NewLoad) {
8420 // Check the resultant load doesn't need a higher alignment than the
8421 // original load.
Bill Wendlingc144a572009-01-30 23:36:47 +00008422 unsigned NewAlign =
Micah Villmow3574eca2012-10-08 16:38:25 +00008423 TLI.getDataLayout()
Eric Christopher503a64d2010-12-09 04:48:06 +00008424 ->getABITypeAlignment(LVT.getTypeForEVT(*DAG.getContext()));
Bill Wendlingc144a572009-01-30 23:36:47 +00008425
Dan Gohmanf560ffa2009-01-28 17:46:25 +00008426 if (NewAlign > Align || !TLI.isOperationLegalOrCustom(ISD::LOAD, LVT))
Dan Gohman475871a2008-07-27 21:46:04 +00008427 return SDValue();
Bill Wendlingc144a572009-01-30 23:36:47 +00008428
Evan Cheng77f0b7a2008-05-13 08:35:03 +00008429 Align = NewAlign;
8430 }
8431
Dan Gohman475871a2008-07-27 21:46:04 +00008432 SDValue NewPtr = LN0->getBasePtr();
Chris Lattnerfa459012010-09-21 16:08:50 +00008433 unsigned PtrOff = 0;
Wesley Peckbf17cfa2010-11-23 03:31:01 +00008434
Eric Christopherd81f17a2010-11-03 20:44:42 +00008435 if (Elt) {
Chris Lattnerfa459012010-09-21 16:08:50 +00008436 PtrOff = LVT.getSizeInBits() * Elt / 8;
Owen Andersone50ed302009-08-10 22:56:29 +00008437 EVT PtrType = NewPtr.getValueType();
Evan Cheng77f0b7a2008-05-13 08:35:03 +00008438 if (TLI.isBigEndian())
Duncan Sands83ec4b62008-06-06 12:08:01 +00008439 PtrOff = VT.getSizeInBits() / 8 - PtrOff;
Bill Wendlingc144a572009-01-30 23:36:47 +00008440 NewPtr = DAG.getNode(ISD::ADD, N->getDebugLoc(), PtrType, NewPtr,
Evan Cheng77f0b7a2008-05-13 08:35:03 +00008441 DAG.getConstant(PtrOff, PtrType));
8442 }
Bill Wendlingc144a572009-01-30 23:36:47 +00008443
Eli Friedman4db4add2011-11-16 23:50:22 +00008444 // The replacement we need to do here is a little tricky: we need to
8445 // replace an extractelement of a load with a load.
8446 // Use ReplaceAllUsesOfValuesWith to do the replacement.
Eli Friedmand6e25602011-12-26 22:49:32 +00008447 // Note that this replacement assumes that the extractvalue is the only
8448 // use of the load; that's okay because we don't want to perform this
8449 // transformation in other cases anyway.
Evan Cheng84387ea2012-03-13 22:00:52 +00008450 SDValue Load;
Evan Chenga03d3662012-03-13 22:16:11 +00008451 SDValue Chain;
Evan Cheng84387ea2012-03-13 22:00:52 +00008452 if (NVT.bitsGT(LVT)) {
8453 // If the result type of vextract is wider than the load, then issue an
8454 // extending load instead.
8455 ISD::LoadExtType ExtType = TLI.isLoadExtLegal(ISD::ZEXTLOAD, LVT)
8456 ? ISD::ZEXTLOAD : ISD::EXTLOAD;
8457 Load = DAG.getExtLoad(ExtType, N->getDebugLoc(), NVT, LN0->getChain(),
8458 NewPtr, LN0->getPointerInfo().getWithOffset(PtrOff),
8459 LVT, LN0->isVolatile(), LN0->isNonTemporal(),Align);
Evan Chenga03d3662012-03-13 22:16:11 +00008460 Chain = Load.getValue(1);
8461 } else {
Evan Cheng84387ea2012-03-13 22:00:52 +00008462 Load = DAG.getLoad(LVT, N->getDebugLoc(), LN0->getChain(), NewPtr,
8463 LN0->getPointerInfo().getWithOffset(PtrOff),
8464 LN0->isVolatile(), LN0->isNonTemporal(),
8465 LN0->isInvariant(), Align);
Evan Chenga03d3662012-03-13 22:16:11 +00008466 Chain = Load.getValue(1);
8467 if (NVT.bitsLT(LVT))
8468 Load = DAG.getNode(ISD::TRUNCATE, N->getDebugLoc(), NVT, Load);
8469 else
8470 Load = DAG.getNode(ISD::BITCAST, N->getDebugLoc(), NVT, Load);
8471 }
Eli Friedman4db4add2011-11-16 23:50:22 +00008472 WorkListRemover DeadNodes(*this);
8473 SDValue From[] = { SDValue(N, 0), SDValue(LN0,1) };
Evan Chenga03d3662012-03-13 22:16:11 +00008474 SDValue To[] = { Load, Chain };
Jakob Stoklund Olesenbc7d4482012-04-20 22:08:46 +00008475 DAG.ReplaceAllUsesOfValuesWith(From, To, 2);
Eli Friedman4db4add2011-11-16 23:50:22 +00008476 // Since we're explcitly calling ReplaceAllUses, add the new node to the
8477 // worklist explicitly as well.
8478 AddToWorkList(Load.getNode());
Craig Topper0c9da212012-03-20 05:28:39 +00008479 AddUsersToWorkList(Load.getNode()); // Add users too
Eli Friedman4db4add2011-11-16 23:50:22 +00008480 // Make sure to revisit this node to clean it up; it will usually be dead.
8481 AddToWorkList(N);
8482 return SDValue(N, 0);
Evan Cheng513da432007-10-06 08:19:55 +00008483 }
Bill Wendlingc144a572009-01-30 23:36:47 +00008484
Dan Gohman475871a2008-07-27 21:46:04 +00008485 return SDValue();
Evan Cheng513da432007-10-06 08:19:55 +00008486}
Evan Cheng513da432007-10-06 08:19:55 +00008487
Michael Liaofac14ab2012-10-23 23:06:52 +00008488// Simplify (build_vec (ext )) to (bitcast (build_vec ))
8489SDValue DAGCombiner::reduceBuildVecExtToExtBuildVec(SDNode *N) {
8490 // We perform this optimization post type-legalization because
8491 // the type-legalizer often scalarizes integer-promoted vectors.
8492 // Performing this optimization before may create bit-casts which
8493 // will be type-legalized to complex code sequences.
8494 // We perform this optimization only before the operation legalizer because we
8495 // may introduce illegal operations.
8496 if (Level != AfterLegalizeVectorOps && Level != AfterLegalizeTypes)
8497 return SDValue();
8498
Dan Gohman7f321562007-06-25 16:23:39 +00008499 unsigned NumInScalars = N->getNumOperands();
Nadav Rotemb00418a2011-10-29 21:23:04 +00008500 DebugLoc dl = N->getDebugLoc();
Owen Andersone50ed302009-08-10 22:56:29 +00008501 EVT VT = N->getValueType(0);
Nadav Rotemb87bdac2012-07-15 08:38:23 +00008502
Nadav Rotemb00418a2011-10-29 21:23:04 +00008503 // Check to see if this is a BUILD_VECTOR of a bunch of values
8504 // which come from any_extend or zero_extend nodes. If so, we can create
8505 // a new BUILD_VECTOR using bit-casts which may enable other BUILD_VECTOR
Nadav Rotemf47368b2011-10-31 20:08:25 +00008506 // optimizations. We do not handle sign-extend because we can't fill the sign
8507 // using shuffles.
Nadav Rotemb00418a2011-10-29 21:23:04 +00008508 EVT SourceType = MVT::Other;
Craig Topperd3b58892012-01-17 09:09:48 +00008509 bool AllAnyExt = true;
Nadav Rotemb87bdac2012-07-15 08:38:23 +00008510
Craig Topperd3b58892012-01-17 09:09:48 +00008511 for (unsigned i = 0; i != NumInScalars; ++i) {
Nadav Rotemb00418a2011-10-29 21:23:04 +00008512 SDValue In = N->getOperand(i);
8513 // Ignore undef inputs.
8514 if (In.getOpcode() == ISD::UNDEF) continue;
8515
8516 bool AnyExt = In.getOpcode() == ISD::ANY_EXTEND;
8517 bool ZeroExt = In.getOpcode() == ISD::ZERO_EXTEND;
8518
Nadav Rotemf47368b2011-10-31 20:08:25 +00008519 // Abort if the element is not an extension.
Nadav Rotemb00418a2011-10-29 21:23:04 +00008520 if (!ZeroExt && !AnyExt) {
Nadav Rotemf47368b2011-10-31 20:08:25 +00008521 SourceType = MVT::Other;
Nadav Rotemb00418a2011-10-29 21:23:04 +00008522 break;
8523 }
8524
8525 // The input is a ZeroExt or AnyExt. Check the original type.
8526 EVT InTy = In.getOperand(0).getValueType();
8527
8528 // Check that all of the widened source types are the same.
8529 if (SourceType == MVT::Other)
Nadav Rotemf47368b2011-10-31 20:08:25 +00008530 // First time.
Nadav Rotemb00418a2011-10-29 21:23:04 +00008531 SourceType = InTy;
8532 else if (InTy != SourceType) {
8533 // Multiple income types. Abort.
Nadav Rotemf47368b2011-10-31 20:08:25 +00008534 SourceType = MVT::Other;
Nadav Rotemb00418a2011-10-29 21:23:04 +00008535 break;
8536 }
8537
8538 // Check if all of the extends are ANY_EXTENDs.
Craig Topperd3b58892012-01-17 09:09:48 +00008539 AllAnyExt &= AnyExt;
Nadav Rotemb00418a2011-10-29 21:23:04 +00008540 }
8541
Nadav Rotemf47368b2011-10-31 20:08:25 +00008542 // In order to have valid types, all of the inputs must be extended from the
8543 // same source type and all of the inputs must be any or zero extend.
8544 // Scalar sizes must be a power of two.
Michael Liaofac14ab2012-10-23 23:06:52 +00008545 EVT OutScalarTy = VT.getScalarType();
Nadav Rotem2ee746b2012-02-12 15:05:31 +00008546 bool ValidTypes = SourceType != MVT::Other &&
Nadav Rotemf47368b2011-10-31 20:08:25 +00008547 isPowerOf2_32(OutScalarTy.getSizeInBits()) &&
8548 isPowerOf2_32(SourceType.getSizeInBits());
8549
Nadav Rotem6431ff92012-03-15 08:49:06 +00008550 // Create a new simpler BUILD_VECTOR sequence which other optimizations can
8551 // turn into a single shuffle instruction.
Michael Liaofac14ab2012-10-23 23:06:52 +00008552 if (!ValidTypes)
8553 return SDValue();
Nadav Rotemb00418a2011-10-29 21:23:04 +00008554
Michael Liaofac14ab2012-10-23 23:06:52 +00008555 bool isLE = TLI.isLittleEndian();
8556 unsigned ElemRatio = OutScalarTy.getSizeInBits()/SourceType.getSizeInBits();
8557 assert(ElemRatio > 1 && "Invalid element size ratio");
8558 SDValue Filler = AllAnyExt ? DAG.getUNDEF(SourceType):
8559 DAG.getConstant(0, SourceType);
Nadav Rotemb00418a2011-10-29 21:23:04 +00008560
Michael Liaofac14ab2012-10-23 23:06:52 +00008561 unsigned NewBVElems = ElemRatio * VT.getVectorNumElements();
8562 SmallVector<SDValue, 8> Ops(NewBVElems, Filler);
Nadav Rotemb00418a2011-10-29 21:23:04 +00008563
Michael Liaofac14ab2012-10-23 23:06:52 +00008564 // Populate the new build_vector
Jakub Staszakadf38912012-10-24 00:38:25 +00008565 for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i) {
Michael Liaofac14ab2012-10-23 23:06:52 +00008566 SDValue Cast = N->getOperand(i);
8567 assert((Cast.getOpcode() == ISD::ANY_EXTEND ||
8568 Cast.getOpcode() == ISD::ZERO_EXTEND ||
8569 Cast.getOpcode() == ISD::UNDEF) && "Invalid cast opcode");
8570 SDValue In;
8571 if (Cast.getOpcode() == ISD::UNDEF)
8572 In = DAG.getUNDEF(SourceType);
8573 else
8574 In = Cast->getOperand(0);
8575 unsigned Index = isLE ? (i * ElemRatio) :
8576 (i * ElemRatio + (ElemRatio - 1));
Nadav Rotemb00418a2011-10-29 21:23:04 +00008577
Michael Liaofac14ab2012-10-23 23:06:52 +00008578 assert(Index < Ops.size() && "Invalid index");
8579 Ops[Index] = In;
Nadav Rotemb00418a2011-10-29 21:23:04 +00008580 }
Chris Lattnerca242442006-03-19 01:27:56 +00008581
Michael Liaofac14ab2012-10-23 23:06:52 +00008582 // The type of the new BUILD_VECTOR node.
8583 EVT VecVT = EVT::getVectorVT(*DAG.getContext(), SourceType, NewBVElems);
8584 assert(VecVT.getSizeInBits() == VT.getSizeInBits() &&
8585 "Invalid vector size");
8586 // Check if the new vector type is legal.
8587 if (!isTypeLegal(VecVT)) return SDValue();
8588
8589 // Make the new BUILD_VECTOR.
8590 SDValue BV = DAG.getNode(ISD::BUILD_VECTOR, dl, VecVT, &Ops[0], Ops.size());
8591
8592 // The new BUILD_VECTOR node has the potential to be further optimized.
8593 AddToWorkList(BV.getNode());
8594 // Bitcast to the desired type.
8595 return DAG.getNode(ISD::BITCAST, dl, VT, BV);
8596}
8597
Michael Liao1a5cc712012-10-24 04:14:18 +00008598SDValue DAGCombiner::reduceBuildVecConvertToConvertBuildVec(SDNode *N) {
8599 EVT VT = N->getValueType(0);
8600
8601 unsigned NumInScalars = N->getNumOperands();
8602 DebugLoc dl = N->getDebugLoc();
8603
8604 EVT SrcVT = MVT::Other;
8605 unsigned Opcode = ISD::DELETED_NODE;
8606 unsigned NumDefs = 0;
8607
8608 for (unsigned i = 0; i != NumInScalars; ++i) {
8609 SDValue In = N->getOperand(i);
8610 unsigned Opc = In.getOpcode();
8611
8612 if (Opc == ISD::UNDEF)
8613 continue;
8614
8615 // If all scalar values are floats and converted from integers.
8616 if (Opcode == ISD::DELETED_NODE &&
8617 (Opc == ISD::UINT_TO_FP || Opc == ISD::SINT_TO_FP)) {
8618 Opcode = Opc;
8619 // If not supported by target, bail out.
8620 if (TLI.getOperationAction(Opcode, VT) != TargetLowering::Legal &&
8621 TLI.getOperationAction(Opcode, VT) != TargetLowering::Custom)
8622 return SDValue();
8623 }
8624 if (Opc != Opcode)
8625 return SDValue();
8626
8627 EVT InVT = In.getOperand(0).getValueType();
8628
8629 // If all scalar values are typed differently, bail out. It's chosen to
8630 // simplify BUILD_VECTOR of integer types.
8631 if (SrcVT == MVT::Other)
8632 SrcVT = InVT;
8633 if (SrcVT != InVT)
8634 return SDValue();
8635 NumDefs++;
8636 }
8637
8638 // If the vector has just one element defined, it's not worth to fold it into
8639 // a vectorized one.
8640 if (NumDefs < 2)
8641 return SDValue();
8642
8643 assert((Opcode == ISD::UINT_TO_FP || Opcode == ISD::SINT_TO_FP)
8644 && "Should only handle conversion from integer to float.");
8645 assert(SrcVT != MVT::Other && "Cannot determine source type!");
8646
8647 EVT NVT = EVT::getVectorVT(*DAG.getContext(), SrcVT, NumInScalars);
8648 SmallVector<SDValue, 8> Opnds;
8649 for (unsigned i = 0; i != NumInScalars; ++i) {
8650 SDValue In = N->getOperand(i);
8651
8652 if (In.getOpcode() == ISD::UNDEF)
8653 Opnds.push_back(DAG.getUNDEF(SrcVT));
8654 else
8655 Opnds.push_back(In.getOperand(0));
8656 }
8657 SDValue BV = DAG.getNode(ISD::BUILD_VECTOR, dl, NVT,
8658 &Opnds[0], Opnds.size());
8659 AddToWorkList(BV.getNode());
8660
8661 return DAG.getNode(Opcode, dl, VT, BV);
8662}
8663
Michael Liaofac14ab2012-10-23 23:06:52 +00008664SDValue DAGCombiner::visitBUILD_VECTOR(SDNode *N) {
8665 unsigned NumInScalars = N->getNumOperands();
8666 DebugLoc dl = N->getDebugLoc();
8667 EVT VT = N->getValueType(0);
8668
8669 // A vector built entirely of undefs is undef.
8670 if (ISD::allOperandsUndef(N))
8671 return DAG.getUNDEF(VT);
8672
8673 SDValue V = reduceBuildVecExtToExtBuildVec(N);
8674 if (V.getNode())
8675 return V;
8676
Michael Liao1a5cc712012-10-24 04:14:18 +00008677 V = reduceBuildVecConvertToConvertBuildVec(N);
8678 if (V.getNode())
8679 return V;
8680
Dan Gohman7f321562007-06-25 16:23:39 +00008681 // Check to see if this is a BUILD_VECTOR of a bunch of EXTRACT_VECTOR_ELT
8682 // operations. If so, and if the EXTRACT_VECTOR_ELT vector inputs come from
8683 // at most two distinct vectors, turn this into a shuffle node.
Duncan Sands00294ca2012-03-19 15:35:44 +00008684
8685 // May only combine to shuffle after legalize if shuffle is legal.
8686 if (LegalOperations &&
8687 !TLI.isOperationLegalOrCustom(ISD::VECTOR_SHUFFLE, VT))
8688 return SDValue();
8689
Dan Gohman475871a2008-07-27 21:46:04 +00008690 SDValue VecIn1, VecIn2;
Chris Lattnerd7648c82006-03-28 20:28:38 +00008691 for (unsigned i = 0; i != NumInScalars; ++i) {
8692 // Ignore undef inputs.
8693 if (N->getOperand(i).getOpcode() == ISD::UNDEF) continue;
Scott Michelfdc40a02009-02-17 22:15:04 +00008694
Dan Gohman7f321562007-06-25 16:23:39 +00008695 // If this input is something other than a EXTRACT_VECTOR_ELT with a
Chris Lattnerd7648c82006-03-28 20:28:38 +00008696 // constant index, bail out.
Dan Gohman7f321562007-06-25 16:23:39 +00008697 if (N->getOperand(i).getOpcode() != ISD::EXTRACT_VECTOR_ELT ||
Chris Lattnerd7648c82006-03-28 20:28:38 +00008698 !isa<ConstantSDNode>(N->getOperand(i).getOperand(1))) {
Dan Gohman475871a2008-07-27 21:46:04 +00008699 VecIn1 = VecIn2 = SDValue(0, 0);
Chris Lattnerd7648c82006-03-28 20:28:38 +00008700 break;
8701 }
Scott Michelfdc40a02009-02-17 22:15:04 +00008702
Nadav Rotem2ee746b2012-02-12 15:05:31 +00008703 // We allow up to two distinct input vectors.
Dan Gohman475871a2008-07-27 21:46:04 +00008704 SDValue ExtractedFromVec = N->getOperand(i).getOperand(0);
Chris Lattnerd7648c82006-03-28 20:28:38 +00008705 if (ExtractedFromVec == VecIn1 || ExtractedFromVec == VecIn2)
8706 continue;
Scott Michelfdc40a02009-02-17 22:15:04 +00008707
Gabor Greifba36cb52008-08-28 21:40:38 +00008708 if (VecIn1.getNode() == 0) {
Chris Lattnerd7648c82006-03-28 20:28:38 +00008709 VecIn1 = ExtractedFromVec;
Gabor Greifba36cb52008-08-28 21:40:38 +00008710 } else if (VecIn2.getNode() == 0) {
Chris Lattnerd7648c82006-03-28 20:28:38 +00008711 VecIn2 = ExtractedFromVec;
8712 } else {
8713 // Too many inputs.
Dan Gohman475871a2008-07-27 21:46:04 +00008714 VecIn1 = VecIn2 = SDValue(0, 0);
Chris Lattnerd7648c82006-03-28 20:28:38 +00008715 break;
8716 }
8717 }
Scott Michelfdc40a02009-02-17 22:15:04 +00008718
Nadav Rotem2ee746b2012-02-12 15:05:31 +00008719 // If everything is good, we can make a shuffle operation.
Gabor Greifba36cb52008-08-28 21:40:38 +00008720 if (VecIn1.getNode()) {
Nate Begeman9008ca62009-04-27 18:41:29 +00008721 SmallVector<int, 8> Mask;
Chris Lattnerd7648c82006-03-28 20:28:38 +00008722 for (unsigned i = 0; i != NumInScalars; ++i) {
8723 if (N->getOperand(i).getOpcode() == ISD::UNDEF) {
Nate Begeman9008ca62009-04-27 18:41:29 +00008724 Mask.push_back(-1);
Chris Lattnerd7648c82006-03-28 20:28:38 +00008725 continue;
8726 }
Scott Michelfdc40a02009-02-17 22:15:04 +00008727
Rafael Espindola15684b22009-04-24 12:40:33 +00008728 // If extracting from the first vector, just use the index directly.
Nate Begeman9008ca62009-04-27 18:41:29 +00008729 SDValue Extract = N->getOperand(i);
Mon P Wang93b74152009-03-17 06:33:10 +00008730 SDValue ExtVal = Extract.getOperand(1);
Chris Lattnerd7648c82006-03-28 20:28:38 +00008731 if (Extract.getOperand(0) == VecIn1) {
Nate Begeman5a5ca152009-04-29 05:20:52 +00008732 unsigned ExtIndex = cast<ConstantSDNode>(ExtVal)->getZExtValue();
8733 if (ExtIndex > VT.getVectorNumElements())
8734 return SDValue();
Wesley Peckbf17cfa2010-11-23 03:31:01 +00008735
Nate Begeman5a5ca152009-04-29 05:20:52 +00008736 Mask.push_back(ExtIndex);
Chris Lattnerd7648c82006-03-28 20:28:38 +00008737 continue;
8738 }
8739
8740 // Otherwise, use InIdx + VecSize
Mon P Wang93b74152009-03-17 06:33:10 +00008741 unsigned Idx = cast<ConstantSDNode>(ExtVal)->getZExtValue();
Nate Begeman9008ca62009-04-27 18:41:29 +00008742 Mask.push_back(Idx+NumInScalars);
Chris Lattnerd7648c82006-03-28 20:28:38 +00008743 }
Scott Michelfdc40a02009-02-17 22:15:04 +00008744
Nadav Rotem2ee746b2012-02-12 15:05:31 +00008745 // We can't generate a shuffle node with mismatched input and output types.
8746 // Attempt to transform a single input vector to the correct type.
8747 if ((VT != VecIn1.getValueType())) {
8748 // We don't support shuffeling between TWO values of different types.
8749 if (VecIn2.getNode() != 0)
8750 return SDValue();
8751
8752 // We only support widening of vectors which are half the size of the
8753 // output registers. For example XMM->YMM widening on X86 with AVX.
8754 if (VecIn1.getValueType().getSizeInBits()*2 != VT.getSizeInBits())
8755 return SDValue();
8756
James Molloy8cd08bf2012-09-10 14:01:21 +00008757 // If the input vector type has a different base type to the output
8758 // vector type, bail out.
8759 if (VecIn1.getValueType().getVectorElementType() !=
8760 VT.getVectorElementType())
8761 return SDValue();
8762
Stepan Dyatkovskiyfdeb9fe2012-08-22 09:33:55 +00008763 // Widen the input vector by adding undef values.
Michael Liaofac14ab2012-10-23 23:06:52 +00008764 VecIn1 = DAG.getNode(ISD::CONCAT_VECTORS, dl, VT,
Stepan Dyatkovskiyfdeb9fe2012-08-22 09:33:55 +00008765 VecIn1, DAG.getUNDEF(VecIn1.getValueType()));
Nadav Rotem2ee746b2012-02-12 15:05:31 +00008766 }
8767
8768 // If VecIn2 is unused then change it to undef.
8769 VecIn2 = VecIn2.getNode() ? VecIn2 : DAG.getUNDEF(VT);
8770
Nadav Rotem6dfabb62012-09-20 08:53:31 +00008771 // Check that we were able to transform all incoming values to the same
8772 // type.
Nadav Rotem0877fdf2012-02-13 12:42:26 +00008773 if (VecIn2.getValueType() != VecIn1.getValueType() ||
8774 VecIn1.getValueType() != VT)
8775 return SDValue();
8776
Nadav Rotem2ee746b2012-02-12 15:05:31 +00008777 // Only type-legal BUILD_VECTOR nodes are converted to shuffle nodes.
Nadav Rotem0877fdf2012-02-13 12:42:26 +00008778 if (!isTypeLegal(VT))
Duncan Sands25cf2272008-11-24 14:53:14 +00008779 return SDValue();
8780
Dan Gohman7f321562007-06-25 16:23:39 +00008781 // Return the new VECTOR_SHUFFLE node.
Nate Begeman9008ca62009-04-27 18:41:29 +00008782 SDValue Ops[2];
Chris Lattnerbd564bf2006-08-08 02:23:42 +00008783 Ops[0] = VecIn1;
Nadav Rotem2ee746b2012-02-12 15:05:31 +00008784 Ops[1] = VecIn2;
Michael Liaofac14ab2012-10-23 23:06:52 +00008785 return DAG.getVectorShuffle(VT, dl, Ops[0], Ops[1], &Mask[0]);
Chris Lattnerd7648c82006-03-28 20:28:38 +00008786 }
Scott Michelfdc40a02009-02-17 22:15:04 +00008787
Dan Gohman475871a2008-07-27 21:46:04 +00008788 return SDValue();
Chris Lattnerd7648c82006-03-28 20:28:38 +00008789}
8790
Dan Gohman475871a2008-07-27 21:46:04 +00008791SDValue DAGCombiner::visitCONCAT_VECTORS(SDNode *N) {
Dan Gohman7f321562007-06-25 16:23:39 +00008792 // TODO: Check to see if this is a CONCAT_VECTORS of a bunch of
8793 // EXTRACT_SUBVECTOR operations. If so, and if the EXTRACT_SUBVECTOR vector
8794 // inputs come from at most two distinct vectors, turn this into a shuffle
8795 // node.
8796
8797 // If we only have one input vector, we don't need to do any concatenation.
Bill Wendlingc144a572009-01-30 23:36:47 +00008798 if (N->getNumOperands() == 1)
Dan Gohman7f321562007-06-25 16:23:39 +00008799 return N->getOperand(0);
Dan Gohman7f321562007-06-25 16:23:39 +00008800
Nadav Rotemb7e230d2012-07-14 21:30:27 +00008801 // Check if all of the operands are undefs.
Nadav Rotemb87bdac2012-07-15 08:38:23 +00008802 if (ISD::allOperandsUndef(N))
Nadav Rotemb7e230d2012-07-14 21:30:27 +00008803 return DAG.getUNDEF(N->getValueType(0));
8804
Dan Gohman475871a2008-07-27 21:46:04 +00008805 return SDValue();
Dan Gohman7f321562007-06-25 16:23:39 +00008806}
8807
Bruno Cardoso Lopese97190f2011-09-20 23:19:33 +00008808SDValue DAGCombiner::visitEXTRACT_SUBVECTOR(SDNode* N) {
8809 EVT NVT = N->getValueType(0);
8810 SDValue V = N->getOperand(0);
8811
8812 if (V->getOpcode() == ISD::INSERT_SUBVECTOR) {
8813 // Handle only simple case where vector being inserted and vector
8814 // being extracted are of same type, and are half size of larger vectors.
8815 EVT BigVT = V->getOperand(0).getValueType();
8816 EVT SmallVT = V->getOperand(1).getValueType();
8817 if (NVT != SmallVT || NVT.getSizeInBits()*2 != BigVT.getSizeInBits())
8818 return SDValue();
8819
Eli Friedman26323442011-12-07 00:11:56 +00008820 // Only handle cases where both indexes are constants with the same type.
Michael Liao13429e22012-10-17 20:48:33 +00008821 ConstantSDNode *ExtIdx = dyn_cast<ConstantSDNode>(N->getOperand(1));
8822 ConstantSDNode *InsIdx = dyn_cast<ConstantSDNode>(V->getOperand(2));
Bruno Cardoso Lopese97190f2011-09-20 23:19:33 +00008823
Eli Friedman26323442011-12-07 00:11:56 +00008824 if (InsIdx && ExtIdx &&
8825 InsIdx->getValueType(0).getSizeInBits() <= 64 &&
8826 ExtIdx->getValueType(0).getSizeInBits() <= 64) {
8827 // Combine:
8828 // (extract_subvec (insert_subvec V1, V2, InsIdx), ExtIdx)
8829 // Into:
8830 // indices are equal => V1
8831 // otherwise => (extract_subvec V1, ExtIdx)
8832 if (InsIdx->getZExtValue() == ExtIdx->getZExtValue())
8833 return V->getOperand(1);
8834 return DAG.getNode(ISD::EXTRACT_SUBVECTOR, N->getDebugLoc(), NVT,
8835 V->getOperand(0), N->getOperand(1));
8836 }
Bruno Cardoso Lopese97190f2011-09-20 23:19:33 +00008837 }
8838
Michael Liao13429e22012-10-17 20:48:33 +00008839 if (V->getOpcode() == ISD::CONCAT_VECTORS) {
8840 // Combine:
8841 // (extract_subvec (concat V1, V2, ...), i)
8842 // Into:
8843 // Vi if possible
Michael Liao9aecdb52012-10-19 03:17:00 +00008844 // Only operand 0 is checked as 'concat' assumes all inputs of the same type.
8845 if (V->getOperand(0).getValueType() != NVT)
8846 return SDValue();
Michael Liao13429e22012-10-17 20:48:33 +00008847 unsigned Idx = dyn_cast<ConstantSDNode>(N->getOperand(1))->getZExtValue();
8848 unsigned NumElems = NVT.getVectorNumElements();
8849 assert((Idx % NumElems) == 0 &&
8850 "IDX in concat is not a multiple of the result vector length.");
8851 return V->getOperand(Idx / NumElems);
8852 }
8853
Bruno Cardoso Lopese97190f2011-09-20 23:19:33 +00008854 return SDValue();
8855}
8856
Dan Gohman475871a2008-07-27 21:46:04 +00008857SDValue DAGCombiner::visitVECTOR_SHUFFLE(SDNode *N) {
Owen Andersone50ed302009-08-10 22:56:29 +00008858 EVT VT = N->getValueType(0);
Nate Begeman9008ca62009-04-27 18:41:29 +00008859 unsigned NumElts = VT.getVectorNumElements();
Chris Lattnerf1d0c622006-03-31 22:16:43 +00008860
Mon P Wangaeb06d22008-11-10 04:46:22 +00008861 SDValue N0 = N->getOperand(0);
Craig Topper481b79c2012-01-04 08:07:43 +00008862 SDValue N1 = N->getOperand(1);
Mon P Wangaeb06d22008-11-10 04:46:22 +00008863
Craig Topperae1bec52012-04-09 05:16:56 +00008864 assert(N0.getValueType() == VT && "Vector shuffle must be normalized in DAG");
Mon P Wangaeb06d22008-11-10 04:46:22 +00008865
Craig Topper481b79c2012-01-04 08:07:43 +00008866 // Canonicalize shuffle undef, undef -> undef
8867 if (N0.getOpcode() == ISD::UNDEF && N1.getOpcode() == ISD::UNDEF)
8868 return DAG.getUNDEF(VT);
8869
8870 ShuffleVectorSDNode *SVN = cast<ShuffleVectorSDNode>(N);
8871
8872 // Canonicalize shuffle v, v -> v, undef
8873 if (N0 == N1) {
8874 SmallVector<int, 8> NewMask;
8875 for (unsigned i = 0; i != NumElts; ++i) {
8876 int Idx = SVN->getMaskElt(i);
8877 if (Idx >= (int)NumElts) Idx -= NumElts;
8878 NewMask.push_back(Idx);
8879 }
8880 return DAG.getVectorShuffle(VT, N->getDebugLoc(), N0, DAG.getUNDEF(VT),
8881 &NewMask[0]);
8882 }
8883
8884 // Canonicalize shuffle undef, v -> v, undef. Commute the shuffle mask.
8885 if (N0.getOpcode() == ISD::UNDEF) {
8886 SmallVector<int, 8> NewMask;
8887 for (unsigned i = 0; i != NumElts; ++i) {
8888 int Idx = SVN->getMaskElt(i);
Craig Topper4b206bd2012-04-09 05:55:33 +00008889 if (Idx >= 0) {
8890 if (Idx < (int)NumElts)
8891 Idx += NumElts;
8892 else
8893 Idx -= NumElts;
8894 }
8895 NewMask.push_back(Idx);
Craig Topper481b79c2012-01-04 08:07:43 +00008896 }
8897 return DAG.getVectorShuffle(VT, N->getDebugLoc(), N1, DAG.getUNDEF(VT),
8898 &NewMask[0]);
8899 }
8900
8901 // Remove references to rhs if it is undef
8902 if (N1.getOpcode() == ISD::UNDEF) {
8903 bool Changed = false;
8904 SmallVector<int, 8> NewMask;
8905 for (unsigned i = 0; i != NumElts; ++i) {
8906 int Idx = SVN->getMaskElt(i);
8907 if (Idx >= (int)NumElts) {
8908 Idx = -1;
8909 Changed = true;
8910 }
8911 NewMask.push_back(Idx);
8912 }
8913 if (Changed)
8914 return DAG.getVectorShuffle(VT, N->getDebugLoc(), N0, N1, &NewMask[0]);
8915 }
Evan Chenge7bec0d2006-07-20 22:44:41 +00008916
Bob Wilson0f1db1a2010-10-28 17:06:14 +00008917 // If it is a splat, check if the argument vector is another splat or a
8918 // build_vector with all scalar elements the same.
Bob Wilson0f1db1a2010-10-28 17:06:14 +00008919 if (SVN->isSplat() && SVN->getSplatIndex() < (int)NumElts) {
Gabor Greifba36cb52008-08-28 21:40:38 +00008920 SDNode *V = N0.getNode();
Evan Cheng917ec982006-07-21 08:25:53 +00008921
Dan Gohman7f321562007-06-25 16:23:39 +00008922 // If this is a bit convert that changes the element type of the vector but
Evan Cheng59569222006-10-16 22:49:37 +00008923 // not the number of vector elements, look through it. Be careful not to
8924 // look though conversions that change things like v4f32 to v2f64.
Wesley Peckbf17cfa2010-11-23 03:31:01 +00008925 if (V->getOpcode() == ISD::BITCAST) {
Dan Gohman475871a2008-07-27 21:46:04 +00008926 SDValue ConvInput = V->getOperand(0);
Evan Cheng29257862008-07-22 20:42:56 +00008927 if (ConvInput.getValueType().isVector() &&
8928 ConvInput.getValueType().getVectorNumElements() == NumElts)
Gabor Greifba36cb52008-08-28 21:40:38 +00008929 V = ConvInput.getNode();
Evan Cheng59569222006-10-16 22:49:37 +00008930 }
8931
Dan Gohman7f321562007-06-25 16:23:39 +00008932 if (V->getOpcode() == ISD::BUILD_VECTOR) {
Bob Wilson0f1db1a2010-10-28 17:06:14 +00008933 assert(V->getNumOperands() == NumElts &&
8934 "BUILD_VECTOR has wrong number of operands");
8935 SDValue Base;
8936 bool AllSame = true;
8937 for (unsigned i = 0; i != NumElts; ++i) {
8938 if (V->getOperand(i).getOpcode() != ISD::UNDEF) {
8939 Base = V->getOperand(i);
8940 break;
Evan Cheng917ec982006-07-21 08:25:53 +00008941 }
Evan Cheng917ec982006-07-21 08:25:53 +00008942 }
Bob Wilson0f1db1a2010-10-28 17:06:14 +00008943 // Splat of <u, u, u, u>, return <u, u, u, u>
8944 if (!Base.getNode())
8945 return N0;
8946 for (unsigned i = 0; i != NumElts; ++i) {
8947 if (V->getOperand(i) != Base) {
8948 AllSame = false;
8949 break;
8950 }
8951 }
8952 // Splat of <x, x, x, x>, return <x, x, x, x>
8953 if (AllSame)
8954 return N0;
Evan Cheng917ec982006-07-21 08:25:53 +00008955 }
8956 }
Nadav Rotem4ac90812012-04-01 19:31:22 +00008957
8958 // If this shuffle node is simply a swizzle of another shuffle node,
Nadav Rotemd16c8d02012-04-07 21:19:08 +00008959 // and it reverses the swizzle of the previous shuffle then we can
8960 // optimize shuffle(shuffle(x, undef), undef) -> x.
Nadav Rotem4ac90812012-04-01 19:31:22 +00008961 if (N0.getOpcode() == ISD::VECTOR_SHUFFLE && Level < AfterLegalizeDAG &&
8962 N1.getOpcode() == ISD::UNDEF) {
8963
Nadav Rotem4ac90812012-04-01 19:31:22 +00008964 ShuffleVectorSDNode *OtherSV = cast<ShuffleVectorSDNode>(N0);
8965
Nadav Rotemd16c8d02012-04-07 21:19:08 +00008966 // Shuffle nodes can only reverse shuffles with a single non-undef value.
8967 if (N0.getOperand(1).getOpcode() != ISD::UNDEF)
8968 return SDValue();
8969
Craig Topperae1bec52012-04-09 05:16:56 +00008970 // The incoming shuffle must be of the same type as the result of the
8971 // current shuffle.
8972 assert(OtherSV->getOperand(0).getValueType() == VT &&
8973 "Shuffle types don't match");
Nadav Rotem4ac90812012-04-01 19:31:22 +00008974
8975 for (unsigned i = 0; i != NumElts; ++i) {
8976 int Idx = SVN->getMaskElt(i);
Craig Topperae1bec52012-04-09 05:16:56 +00008977 assert(Idx < (int)NumElts && "Index references undef operand");
Nadav Rotem4ac90812012-04-01 19:31:22 +00008978 // Next, this index comes from the first value, which is the incoming
8979 // shuffle. Adopt the incoming index.
8980 if (Idx >= 0)
8981 Idx = OtherSV->getMaskElt(Idx);
8982
Nadav Rotemd16c8d02012-04-07 21:19:08 +00008983 // The combined shuffle must map each index to itself.
Craig Topperae1bec52012-04-09 05:16:56 +00008984 if (Idx >= 0 && (unsigned)Idx != i)
Nadav Rotemd16c8d02012-04-07 21:19:08 +00008985 return SDValue();
Nadav Rotem4ac90812012-04-01 19:31:22 +00008986 }
Nadav Rotemd16c8d02012-04-07 21:19:08 +00008987
8988 return OtherSV->getOperand(0);
Nadav Rotem4ac90812012-04-01 19:31:22 +00008989 }
8990
Dan Gohman475871a2008-07-27 21:46:04 +00008991 return SDValue();
Chris Lattnerf1d0c622006-03-31 22:16:43 +00008992}
8993
Jim Grosbach9a526492010-06-23 16:07:42 +00008994SDValue DAGCombiner::visitMEMBARRIER(SDNode* N) {
8995 if (!TLI.getShouldFoldAtomicFences())
8996 return SDValue();
8997
8998 SDValue atomic = N->getOperand(0);
8999 switch (atomic.getOpcode()) {
9000 case ISD::ATOMIC_CMP_SWAP:
9001 case ISD::ATOMIC_SWAP:
9002 case ISD::ATOMIC_LOAD_ADD:
9003 case ISD::ATOMIC_LOAD_SUB:
9004 case ISD::ATOMIC_LOAD_AND:
9005 case ISD::ATOMIC_LOAD_OR:
9006 case ISD::ATOMIC_LOAD_XOR:
9007 case ISD::ATOMIC_LOAD_NAND:
9008 case ISD::ATOMIC_LOAD_MIN:
9009 case ISD::ATOMIC_LOAD_MAX:
9010 case ISD::ATOMIC_LOAD_UMIN:
9011 case ISD::ATOMIC_LOAD_UMAX:
9012 break;
9013 default:
9014 return SDValue();
9015 }
9016
9017 SDValue fence = atomic.getOperand(0);
9018 if (fence.getOpcode() != ISD::MEMBARRIER)
9019 return SDValue();
9020
9021 switch (atomic.getOpcode()) {
9022 case ISD::ATOMIC_CMP_SWAP:
9023 return SDValue(DAG.UpdateNodeOperands(atomic.getNode(),
9024 fence.getOperand(0),
9025 atomic.getOperand(1), atomic.getOperand(2),
9026 atomic.getOperand(3)), atomic.getResNo());
9027 case ISD::ATOMIC_SWAP:
9028 case ISD::ATOMIC_LOAD_ADD:
9029 case ISD::ATOMIC_LOAD_SUB:
9030 case ISD::ATOMIC_LOAD_AND:
9031 case ISD::ATOMIC_LOAD_OR:
9032 case ISD::ATOMIC_LOAD_XOR:
9033 case ISD::ATOMIC_LOAD_NAND:
9034 case ISD::ATOMIC_LOAD_MIN:
9035 case ISD::ATOMIC_LOAD_MAX:
9036 case ISD::ATOMIC_LOAD_UMIN:
9037 case ISD::ATOMIC_LOAD_UMAX:
9038 return SDValue(DAG.UpdateNodeOperands(atomic.getNode(),
9039 fence.getOperand(0),
9040 atomic.getOperand(1), atomic.getOperand(2)),
9041 atomic.getResNo());
9042 default:
9043 return SDValue();
9044 }
9045}
9046
Evan Cheng44f1f092006-04-20 08:56:16 +00009047/// XformToShuffleWithZero - Returns a vector_shuffle if it able to transform
Dan Gohman7f321562007-06-25 16:23:39 +00009048/// an AND to a vector_shuffle with the destination vector and a zero vector.
9049/// e.g. AND V, <0xffffffff, 0, 0xffffffff, 0>. ==>
Evan Cheng44f1f092006-04-20 08:56:16 +00009050/// vector_shuffle V, Zero, <0, 4, 2, 4>
Dan Gohman475871a2008-07-27 21:46:04 +00009051SDValue DAGCombiner::XformToShuffleWithZero(SDNode *N) {
Owen Andersone50ed302009-08-10 22:56:29 +00009052 EVT VT = N->getValueType(0);
Nate Begeman9008ca62009-04-27 18:41:29 +00009053 DebugLoc dl = N->getDebugLoc();
Dan Gohman475871a2008-07-27 21:46:04 +00009054 SDValue LHS = N->getOperand(0);
9055 SDValue RHS = N->getOperand(1);
Dan Gohman7f321562007-06-25 16:23:39 +00009056 if (N->getOpcode() == ISD::AND) {
Wesley Peckbf17cfa2010-11-23 03:31:01 +00009057 if (RHS.getOpcode() == ISD::BITCAST)
Evan Cheng44f1f092006-04-20 08:56:16 +00009058 RHS = RHS.getOperand(0);
Dan Gohman7f321562007-06-25 16:23:39 +00009059 if (RHS.getOpcode() == ISD::BUILD_VECTOR) {
Nate Begeman9008ca62009-04-27 18:41:29 +00009060 SmallVector<int, 8> Indices;
9061 unsigned NumElts = RHS.getNumOperands();
Evan Cheng44f1f092006-04-20 08:56:16 +00009062 for (unsigned i = 0; i != NumElts; ++i) {
Dan Gohman475871a2008-07-27 21:46:04 +00009063 SDValue Elt = RHS.getOperand(i);
Evan Cheng44f1f092006-04-20 08:56:16 +00009064 if (!isa<ConstantSDNode>(Elt))
Dan Gohman475871a2008-07-27 21:46:04 +00009065 return SDValue();
Craig Topperb7135e52012-04-09 05:59:53 +00009066
9067 if (cast<ConstantSDNode>(Elt)->isAllOnesValue())
Nate Begeman9008ca62009-04-27 18:41:29 +00009068 Indices.push_back(i);
Evan Cheng44f1f092006-04-20 08:56:16 +00009069 else if (cast<ConstantSDNode>(Elt)->isNullValue())
Nate Begeman9008ca62009-04-27 18:41:29 +00009070 Indices.push_back(NumElts);
Evan Cheng44f1f092006-04-20 08:56:16 +00009071 else
Dan Gohman475871a2008-07-27 21:46:04 +00009072 return SDValue();
Evan Cheng44f1f092006-04-20 08:56:16 +00009073 }
9074
9075 // Let's see if the target supports this vector_shuffle.
Owen Andersone50ed302009-08-10 22:56:29 +00009076 EVT RVT = RHS.getValueType();
Nate Begeman9008ca62009-04-27 18:41:29 +00009077 if (!TLI.isVectorClearMaskLegal(Indices, RVT))
Dan Gohman475871a2008-07-27 21:46:04 +00009078 return SDValue();
Evan Cheng44f1f092006-04-20 08:56:16 +00009079
Dan Gohman7f321562007-06-25 16:23:39 +00009080 // Return the new VECTOR_SHUFFLE node.
Dan Gohman8a55ce42009-09-23 21:02:20 +00009081 EVT EltVT = RVT.getVectorElementType();
Nate Begeman9008ca62009-04-27 18:41:29 +00009082 SmallVector<SDValue,8> ZeroOps(RVT.getVectorNumElements(),
Dan Gohman8a55ce42009-09-23 21:02:20 +00009083 DAG.getConstant(0, EltVT));
Nate Begeman9008ca62009-04-27 18:41:29 +00009084 SDValue Zero = DAG.getNode(ISD::BUILD_VECTOR, N->getDebugLoc(),
9085 RVT, &ZeroOps[0], ZeroOps.size());
Wesley Peckbf17cfa2010-11-23 03:31:01 +00009086 LHS = DAG.getNode(ISD::BITCAST, dl, RVT, LHS);
Nate Begeman9008ca62009-04-27 18:41:29 +00009087 SDValue Shuf = DAG.getVectorShuffle(RVT, dl, LHS, Zero, &Indices[0]);
Wesley Peckbf17cfa2010-11-23 03:31:01 +00009088 return DAG.getNode(ISD::BITCAST, dl, VT, Shuf);
Evan Cheng44f1f092006-04-20 08:56:16 +00009089 }
9090 }
Bill Wendling836ca7d2009-01-30 23:59:18 +00009091
Dan Gohman475871a2008-07-27 21:46:04 +00009092 return SDValue();
Evan Cheng44f1f092006-04-20 08:56:16 +00009093}
9094
Dan Gohman7f321562007-06-25 16:23:39 +00009095/// SimplifyVBinOp - Visit a binary vector operation, like ADD.
Dan Gohman475871a2008-07-27 21:46:04 +00009096SDValue DAGCombiner::SimplifyVBinOp(SDNode *N) {
Dan Gohman7f321562007-06-25 16:23:39 +00009097 // After legalize, the target may be depending on adds and other
9098 // binary ops to provide legal ways to construct constants or other
9099 // things. Simplifying them may result in a loss of legality.
Duncan Sands25cf2272008-11-24 14:53:14 +00009100 if (LegalOperations) return SDValue();
Dan Gohman7f321562007-06-25 16:23:39 +00009101
Bob Wilsond7273432010-12-17 23:06:49 +00009102 assert(N->getValueType(0).isVector() &&
9103 "SimplifyVBinOp only works on vectors!");
Dan Gohman7f321562007-06-25 16:23:39 +00009104
Dan Gohman475871a2008-07-27 21:46:04 +00009105 SDValue LHS = N->getOperand(0);
9106 SDValue RHS = N->getOperand(1);
9107 SDValue Shuffle = XformToShuffleWithZero(N);
Gabor Greifba36cb52008-08-28 21:40:38 +00009108 if (Shuffle.getNode()) return Shuffle;
Evan Cheng44f1f092006-04-20 08:56:16 +00009109
Dan Gohman7f321562007-06-25 16:23:39 +00009110 // If the LHS and RHS are BUILD_VECTOR nodes, see if we can constant fold
Chris Lattneredab1b92006-04-02 03:25:57 +00009111 // this operation.
Scott Michelfdc40a02009-02-17 22:15:04 +00009112 if (LHS.getOpcode() == ISD::BUILD_VECTOR &&
Dan Gohman7f321562007-06-25 16:23:39 +00009113 RHS.getOpcode() == ISD::BUILD_VECTOR) {
Dan Gohman475871a2008-07-27 21:46:04 +00009114 SmallVector<SDValue, 8> Ops;
Dan Gohman7f321562007-06-25 16:23:39 +00009115 for (unsigned i = 0, e = LHS.getNumOperands(); i != e; ++i) {
Dan Gohman475871a2008-07-27 21:46:04 +00009116 SDValue LHSOp = LHS.getOperand(i);
9117 SDValue RHSOp = RHS.getOperand(i);
Chris Lattneredab1b92006-04-02 03:25:57 +00009118 // If these two elements can't be folded, bail out.
9119 if ((LHSOp.getOpcode() != ISD::UNDEF &&
9120 LHSOp.getOpcode() != ISD::Constant &&
9121 LHSOp.getOpcode() != ISD::ConstantFP) ||
9122 (RHSOp.getOpcode() != ISD::UNDEF &&
9123 RHSOp.getOpcode() != ISD::Constant &&
9124 RHSOp.getOpcode() != ISD::ConstantFP))
9125 break;
Bill Wendling836ca7d2009-01-30 23:59:18 +00009126
Evan Cheng7b336a82006-05-31 06:08:35 +00009127 // Can't fold divide by zero.
Dan Gohman7f321562007-06-25 16:23:39 +00009128 if (N->getOpcode() == ISD::SDIV || N->getOpcode() == ISD::UDIV ||
9129 N->getOpcode() == ISD::FDIV) {
Evan Cheng7b336a82006-05-31 06:08:35 +00009130 if ((RHSOp.getOpcode() == ISD::Constant &&
Gabor Greifba36cb52008-08-28 21:40:38 +00009131 cast<ConstantSDNode>(RHSOp.getNode())->isNullValue()) ||
Evan Cheng7b336a82006-05-31 06:08:35 +00009132 (RHSOp.getOpcode() == ISD::ConstantFP &&
Gabor Greifba36cb52008-08-28 21:40:38 +00009133 cast<ConstantFPSDNode>(RHSOp.getNode())->getValueAPF().isZero()))
Evan Cheng7b336a82006-05-31 06:08:35 +00009134 break;
9135 }
Bill Wendling836ca7d2009-01-30 23:59:18 +00009136
Bob Wilsond7273432010-12-17 23:06:49 +00009137 EVT VT = LHSOp.getValueType();
Bob Wilsondb2b18f2011-10-18 17:34:47 +00009138 EVT RVT = RHSOp.getValueType();
9139 if (RVT != VT) {
9140 // Integer BUILD_VECTOR operands may have types larger than the element
9141 // size (e.g., when the element type is not legal). Prior to type
9142 // legalization, the types may not match between the two BUILD_VECTORS.
9143 // Truncate one of the operands to make them match.
9144 if (RVT.getSizeInBits() > VT.getSizeInBits()) {
9145 RHSOp = DAG.getNode(ISD::TRUNCATE, N->getDebugLoc(), VT, RHSOp);
9146 } else {
9147 LHSOp = DAG.getNode(ISD::TRUNCATE, N->getDebugLoc(), RVT, LHSOp);
9148 VT = RVT;
9149 }
9150 }
Bob Wilsond7273432010-12-17 23:06:49 +00009151 SDValue FoldOp = DAG.getNode(N->getOpcode(), LHS.getDebugLoc(), VT,
Evan Chenga0839882010-05-18 00:03:40 +00009152 LHSOp, RHSOp);
9153 if (FoldOp.getOpcode() != ISD::UNDEF &&
9154 FoldOp.getOpcode() != ISD::Constant &&
9155 FoldOp.getOpcode() != ISD::ConstantFP)
9156 break;
9157 Ops.push_back(FoldOp);
9158 AddToWorkList(FoldOp.getNode());
Chris Lattneredab1b92006-04-02 03:25:57 +00009159 }
Scott Michelfdc40a02009-02-17 22:15:04 +00009160
Bob Wilsond7273432010-12-17 23:06:49 +00009161 if (Ops.size() == LHS.getNumOperands())
9162 return DAG.getNode(ISD::BUILD_VECTOR, N->getDebugLoc(),
9163 LHS.getValueType(), &Ops[0], Ops.size());
Chris Lattneredab1b92006-04-02 03:25:57 +00009164 }
Scott Michelfdc40a02009-02-17 22:15:04 +00009165
Dan Gohman475871a2008-07-27 21:46:04 +00009166 return SDValue();
Chris Lattneredab1b92006-04-02 03:25:57 +00009167}
9168
Craig Topperdd201ff2012-09-11 01:45:21 +00009169/// SimplifyVUnaryOp - Visit a binary vector operation, like FABS/FNEG.
9170SDValue DAGCombiner::SimplifyVUnaryOp(SDNode *N) {
9171 // After legalize, the target may be depending on adds and other
9172 // binary ops to provide legal ways to construct constants or other
9173 // things. Simplifying them may result in a loss of legality.
9174 if (LegalOperations) return SDValue();
9175
9176 assert(N->getValueType(0).isVector() &&
9177 "SimplifyVUnaryOp only works on vectors!");
9178
9179 SDValue N0 = N->getOperand(0);
9180
9181 if (N0.getOpcode() != ISD::BUILD_VECTOR)
9182 return SDValue();
9183
9184 // Operand is a BUILD_VECTOR node, see if we can constant fold it.
9185 SmallVector<SDValue, 8> Ops;
9186 for (unsigned i = 0, e = N0.getNumOperands(); i != e; ++i) {
9187 SDValue Op = N0.getOperand(i);
9188 if (Op.getOpcode() != ISD::UNDEF &&
9189 Op.getOpcode() != ISD::ConstantFP)
9190 break;
9191 EVT EltVT = Op.getValueType();
9192 SDValue FoldOp = DAG.getNode(N->getOpcode(), N0.getDebugLoc(), EltVT, Op);
9193 if (FoldOp.getOpcode() != ISD::UNDEF &&
9194 FoldOp.getOpcode() != ISD::ConstantFP)
9195 break;
9196 Ops.push_back(FoldOp);
9197 AddToWorkList(FoldOp.getNode());
9198 }
9199
9200 if (Ops.size() != N0.getNumOperands())
9201 return SDValue();
9202
9203 return DAG.getNode(ISD::BUILD_VECTOR, N->getDebugLoc(),
9204 N0.getValueType(), &Ops[0], Ops.size());
9205}
9206
Bill Wendling836ca7d2009-01-30 23:59:18 +00009207SDValue DAGCombiner::SimplifySelect(DebugLoc DL, SDValue N0,
9208 SDValue N1, SDValue N2){
Nate Begemanf845b452005-10-08 00:29:44 +00009209 assert(N0.getOpcode() ==ISD::SETCC && "First argument must be a SetCC node!");
Scott Michelfdc40a02009-02-17 22:15:04 +00009210
Bill Wendling836ca7d2009-01-30 23:59:18 +00009211 SDValue SCC = SimplifySelectCC(DL, N0.getOperand(0), N0.getOperand(1), N1, N2,
Nate Begemanf845b452005-10-08 00:29:44 +00009212 cast<CondCodeSDNode>(N0.getOperand(2))->get());
Bill Wendling836ca7d2009-01-30 23:59:18 +00009213
Nate Begemanf845b452005-10-08 00:29:44 +00009214 // If we got a simplified select_cc node back from SimplifySelectCC, then
9215 // break it down into a new SETCC node, and a new SELECT node, and then return
9216 // the SELECT node, since we were called with a SELECT node.
Gabor Greifba36cb52008-08-28 21:40:38 +00009217 if (SCC.getNode()) {
Nate Begemanf845b452005-10-08 00:29:44 +00009218 // Check to see if we got a select_cc back (to turn into setcc/select).
9219 // Otherwise, just return whatever node we got back, like fabs.
9220 if (SCC.getOpcode() == ISD::SELECT_CC) {
Bill Wendling836ca7d2009-01-30 23:59:18 +00009221 SDValue SETCC = DAG.getNode(ISD::SETCC, N0.getDebugLoc(),
9222 N0.getValueType(),
Scott Michelfdc40a02009-02-17 22:15:04 +00009223 SCC.getOperand(0), SCC.getOperand(1),
Bill Wendling836ca7d2009-01-30 23:59:18 +00009224 SCC.getOperand(4));
Gabor Greifba36cb52008-08-28 21:40:38 +00009225 AddToWorkList(SETCC.getNode());
Bill Wendling836ca7d2009-01-30 23:59:18 +00009226 return DAG.getNode(ISD::SELECT, SCC.getDebugLoc(), SCC.getValueType(),
9227 SCC.getOperand(2), SCC.getOperand(3), SETCC);
Nate Begemanf845b452005-10-08 00:29:44 +00009228 }
Bill Wendling836ca7d2009-01-30 23:59:18 +00009229
Nate Begemanf845b452005-10-08 00:29:44 +00009230 return SCC;
9231 }
Dan Gohman475871a2008-07-27 21:46:04 +00009232 return SDValue();
Nate Begeman44728a72005-09-19 22:34:01 +00009233}
9234
Chris Lattner40c62d52005-10-18 06:04:22 +00009235/// SimplifySelectOps - Given a SELECT or a SELECT_CC node, where LHS and RHS
9236/// are the two values being selected between, see if we can simplify the
Chris Lattner729c6d12006-05-27 00:43:02 +00009237/// select. Callers of this should assume that TheSelect is deleted if this
9238/// returns true. As such, they should return the appropriate thing (e.g. the
9239/// node) back to the top-level of the DAG combiner loop to avoid it being
9240/// looked at.
Scott Michelfdc40a02009-02-17 22:15:04 +00009241bool DAGCombiner::SimplifySelectOps(SDNode *TheSelect, SDValue LHS,
Dan Gohman475871a2008-07-27 21:46:04 +00009242 SDValue RHS) {
Scott Michelfdc40a02009-02-17 22:15:04 +00009243
Nadav Rotemf94fdb62011-02-11 19:57:47 +00009244 // Cannot simplify select with vector condition
9245 if (TheSelect->getOperand(0).getValueType().isVector()) return false;
9246
Chris Lattner40c62d52005-10-18 06:04:22 +00009247 // If this is a select from two identical things, try to pull the operation
9248 // through the select.
Chris Lattner18061612010-09-21 15:46:59 +00009249 if (LHS.getOpcode() != RHS.getOpcode() ||
9250 !LHS.hasOneUse() || !RHS.hasOneUse())
9251 return false;
Wesley Peckbf17cfa2010-11-23 03:31:01 +00009252
Chris Lattner18061612010-09-21 15:46:59 +00009253 // If this is a load and the token chain is identical, replace the select
9254 // of two loads with a load through a select of the address to load from.
9255 // This triggers in things like "select bool X, 10.0, 123.0" after the FP
9256 // constants have been dropped into the constant pool.
9257 if (LHS.getOpcode() == ISD::LOAD) {
9258 LoadSDNode *LLD = cast<LoadSDNode>(LHS);
9259 LoadSDNode *RLD = cast<LoadSDNode>(RHS);
Wesley Peckbf17cfa2010-11-23 03:31:01 +00009260
Chris Lattner18061612010-09-21 15:46:59 +00009261 // Token chains must be identical.
9262 if (LHS.getOperand(0) != RHS.getOperand(0) ||
Duncan Sandsd4b9c172008-06-13 19:07:40 +00009263 // Do not let this transformation reduce the number of volatile loads.
Chris Lattner18061612010-09-21 15:46:59 +00009264 LLD->isVolatile() || RLD->isVolatile() ||
9265 // If this is an EXTLOAD, the VT's must match.
9266 LLD->getMemoryVT() != RLD->getMemoryVT() ||
Duncan Sandsdcfd3a72010-11-18 20:05:18 +00009267 // If this is an EXTLOAD, the kind of extension must match.
9268 (LLD->getExtensionType() != RLD->getExtensionType() &&
9269 // The only exception is if one of the extensions is anyext.
9270 LLD->getExtensionType() != ISD::EXTLOAD &&
9271 RLD->getExtensionType() != ISD::EXTLOAD) ||
Dan Gohman75832d72009-10-31 14:14:04 +00009272 // FIXME: this discards src value information. This is
9273 // over-conservative. It would be beneficial to be able to remember
Mon P Wangfe240b12010-01-11 20:12:49 +00009274 // both potential memory locations. Since we are discarding
9275 // src value info, don't do the transformation if the memory
9276 // locations are not in the default address space.
Chris Lattner18061612010-09-21 15:46:59 +00009277 LLD->getPointerInfo().getAddrSpace() != 0 ||
9278 RLD->getPointerInfo().getAddrSpace() != 0)
9279 return false;
Wesley Peckbf17cfa2010-11-23 03:31:01 +00009280
Chris Lattnerf1658062010-09-21 15:58:55 +00009281 // Check that the select condition doesn't reach either load. If so,
9282 // folding this will induce a cycle into the DAG. If not, this is safe to
9283 // xform, so create a select of the addresses.
Chris Lattner18061612010-09-21 15:46:59 +00009284 SDValue Addr;
9285 if (TheSelect->getOpcode() == ISD::SELECT) {
Chris Lattnerf1658062010-09-21 15:58:55 +00009286 SDNode *CondNode = TheSelect->getOperand(0).getNode();
9287 if ((LLD->hasAnyUseOfValue(1) && LLD->isPredecessorOf(CondNode)) ||
9288 (RLD->hasAnyUseOfValue(1) && RLD->isPredecessorOf(CondNode)))
9289 return false;
Nadav Rotem1c5bf3f2012-10-18 18:06:48 +00009290 // The loads must not depend on one another.
9291 if (LLD->isPredecessorOf(RLD) ||
9292 RLD->isPredecessorOf(LLD))
9293 return false;
Chris Lattnerf1658062010-09-21 15:58:55 +00009294 Addr = DAG.getNode(ISD::SELECT, TheSelect->getDebugLoc(),
9295 LLD->getBasePtr().getValueType(),
9296 TheSelect->getOperand(0), LLD->getBasePtr(),
9297 RLD->getBasePtr());
Chris Lattner18061612010-09-21 15:46:59 +00009298 } else { // Otherwise SELECT_CC
Chris Lattnerf1658062010-09-21 15:58:55 +00009299 SDNode *CondLHS = TheSelect->getOperand(0).getNode();
9300 SDNode *CondRHS = TheSelect->getOperand(1).getNode();
9301
9302 if ((LLD->hasAnyUseOfValue(1) &&
9303 (LLD->isPredecessorOf(CondLHS) || LLD->isPredecessorOf(CondRHS))) ||
Chris Lattner77d95212012-03-27 16:27:21 +00009304 (RLD->hasAnyUseOfValue(1) &&
9305 (RLD->isPredecessorOf(CondLHS) || RLD->isPredecessorOf(CondRHS))))
Chris Lattnerf1658062010-09-21 15:58:55 +00009306 return false;
Wesley Peckbf17cfa2010-11-23 03:31:01 +00009307
Chris Lattnerf1658062010-09-21 15:58:55 +00009308 Addr = DAG.getNode(ISD::SELECT_CC, TheSelect->getDebugLoc(),
9309 LLD->getBasePtr().getValueType(),
9310 TheSelect->getOperand(0),
9311 TheSelect->getOperand(1),
9312 LLD->getBasePtr(), RLD->getBasePtr(),
9313 TheSelect->getOperand(4));
Chris Lattner18061612010-09-21 15:46:59 +00009314 }
9315
Chris Lattnerf1658062010-09-21 15:58:55 +00009316 SDValue Load;
9317 if (LLD->getExtensionType() == ISD::NON_EXTLOAD) {
9318 Load = DAG.getLoad(TheSelect->getValueType(0),
9319 TheSelect->getDebugLoc(),
9320 // FIXME: Discards pointer info.
9321 LLD->getChain(), Addr, MachinePointerInfo(),
9322 LLD->isVolatile(), LLD->isNonTemporal(),
Pete Cooperd752e0f2011-11-08 18:42:53 +00009323 LLD->isInvariant(), LLD->getAlignment());
Chris Lattnerf1658062010-09-21 15:58:55 +00009324 } else {
Duncan Sandsb9064bb2010-11-18 21:16:28 +00009325 Load = DAG.getExtLoad(LLD->getExtensionType() == ISD::EXTLOAD ?
9326 RLD->getExtensionType() : LLD->getExtensionType(),
Chris Lattnerf1658062010-09-21 15:58:55 +00009327 TheSelect->getDebugLoc(),
Stuart Hastingsa9011292011-02-16 16:23:55 +00009328 TheSelect->getValueType(0),
Chris Lattnerf1658062010-09-21 15:58:55 +00009329 // FIXME: Discards pointer info.
9330 LLD->getChain(), Addr, MachinePointerInfo(),
9331 LLD->getMemoryVT(), LLD->isVolatile(),
9332 LLD->isNonTemporal(), LLD->getAlignment());
Chris Lattner40c62d52005-10-18 06:04:22 +00009333 }
Chris Lattnerf1658062010-09-21 15:58:55 +00009334
9335 // Users of the select now use the result of the load.
9336 CombineTo(TheSelect, Load);
9337
9338 // Users of the old loads now use the new load's chain. We know the
9339 // old-load value is dead now.
9340 CombineTo(LHS.getNode(), Load.getValue(0), Load.getValue(1));
9341 CombineTo(RHS.getNode(), Load.getValue(0), Load.getValue(1));
9342 return true;
Chris Lattner40c62d52005-10-18 06:04:22 +00009343 }
Scott Michelfdc40a02009-02-17 22:15:04 +00009344
Chris Lattner40c62d52005-10-18 06:04:22 +00009345 return false;
9346}
9347
Chris Lattner600fec32009-03-11 05:08:08 +00009348/// SimplifySelectCC - Simplify an expression of the form (N0 cond N1) ? N2 : N3
9349/// where 'cond' is the comparison specified by CC.
Scott Michelfdc40a02009-02-17 22:15:04 +00009350SDValue DAGCombiner::SimplifySelectCC(DebugLoc DL, SDValue N0, SDValue N1,
Dan Gohman475871a2008-07-27 21:46:04 +00009351 SDValue N2, SDValue N3,
9352 ISD::CondCode CC, bool NotExtCompare) {
Chris Lattner600fec32009-03-11 05:08:08 +00009353 // (x ? y : y) -> y.
9354 if (N2 == N3) return N2;
Wesley Peckbf17cfa2010-11-23 03:31:01 +00009355
Owen Andersone50ed302009-08-10 22:56:29 +00009356 EVT VT = N2.getValueType();
Gabor Greifba36cb52008-08-28 21:40:38 +00009357 ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1.getNode());
9358 ConstantSDNode *N2C = dyn_cast<ConstantSDNode>(N2.getNode());
9359 ConstantSDNode *N3C = dyn_cast<ConstantSDNode>(N3.getNode());
Nate Begemanf845b452005-10-08 00:29:44 +00009360
9361 // Determine if the condition we're dealing with is constant
Duncan Sands5480c042009-01-01 15:52:00 +00009362 SDValue SCC = SimplifySetCC(TLI.getSetCCResultType(N0.getValueType()),
Dale Johannesenff97d4f2009-02-03 00:47:48 +00009363 N0, N1, CC, DL, false);
Gabor Greifba36cb52008-08-28 21:40:38 +00009364 if (SCC.getNode()) AddToWorkList(SCC.getNode());
9365 ConstantSDNode *SCCC = dyn_cast_or_null<ConstantSDNode>(SCC.getNode());
Nate Begemanf845b452005-10-08 00:29:44 +00009366
9367 // fold select_cc true, x, y -> x
Dan Gohman002e5d02008-03-13 22:13:53 +00009368 if (SCCC && !SCCC->isNullValue())
Nate Begemanf845b452005-10-08 00:29:44 +00009369 return N2;
9370 // fold select_cc false, x, y -> y
Dan Gohman002e5d02008-03-13 22:13:53 +00009371 if (SCCC && SCCC->isNullValue())
Nate Begemanf845b452005-10-08 00:29:44 +00009372 return N3;
Scott Michelfdc40a02009-02-17 22:15:04 +00009373
Nate Begemanf845b452005-10-08 00:29:44 +00009374 // Check to see if we can simplify the select into an fabs node
9375 if (ConstantFPSDNode *CFP = dyn_cast<ConstantFPSDNode>(N1)) {
9376 // Allow either -0.0 or 0.0
Dale Johannesen87503a62007-08-25 22:10:57 +00009377 if (CFP->getValueAPF().isZero()) {
Nate Begemanf845b452005-10-08 00:29:44 +00009378 // select (setg[te] X, +/-0.0), X, fneg(X) -> fabs
9379 if ((CC == ISD::SETGE || CC == ISD::SETGT) &&
9380 N0 == N2 && N3.getOpcode() == ISD::FNEG &&
9381 N2 == N3.getOperand(0))
Bill Wendling836ca7d2009-01-30 23:59:18 +00009382 return DAG.getNode(ISD::FABS, DL, VT, N0);
Scott Michelfdc40a02009-02-17 22:15:04 +00009383
Nate Begemanf845b452005-10-08 00:29:44 +00009384 // select (setl[te] X, +/-0.0), fneg(X), X -> fabs
9385 if ((CC == ISD::SETLT || CC == ISD::SETLE) &&
9386 N0 == N3 && N2.getOpcode() == ISD::FNEG &&
9387 N2.getOperand(0) == N3)
Bill Wendling836ca7d2009-01-30 23:59:18 +00009388 return DAG.getNode(ISD::FABS, DL, VT, N3);
Nate Begemanf845b452005-10-08 00:29:44 +00009389 }
9390 }
Wesley Peckbf17cfa2010-11-23 03:31:01 +00009391
Chris Lattner600fec32009-03-11 05:08:08 +00009392 // Turn "(a cond b) ? 1.0f : 2.0f" into "load (tmp + ((a cond b) ? 0 : 4)"
9393 // where "tmp" is a constant pool entry containing an array with 1.0 and 2.0
9394 // in it. This is a win when the constant is not otherwise available because
9395 // it replaces two constant pool loads with one. We only do this if the FP
9396 // type is known to be legal, because if it isn't, then we are before legalize
9397 // types an we want the other legalization to happen first (e.g. to avoid
Mon P Wang0b7a7862009-03-14 00:25:19 +00009398 // messing with soft float) and if the ConstantFP is not legal, because if
9399 // it is legal, we may not need to store the FP constant in a constant pool.
Chris Lattner600fec32009-03-11 05:08:08 +00009400 if (ConstantFPSDNode *TV = dyn_cast<ConstantFPSDNode>(N2))
9401 if (ConstantFPSDNode *FV = dyn_cast<ConstantFPSDNode>(N3)) {
9402 if (TLI.isTypeLegal(N2.getValueType()) &&
Mon P Wang0b7a7862009-03-14 00:25:19 +00009403 (TLI.getOperationAction(ISD::ConstantFP, N2.getValueType()) !=
9404 TargetLowering::Legal) &&
Chris Lattner600fec32009-03-11 05:08:08 +00009405 // If both constants have multiple uses, then we won't need to do an
9406 // extra load, they are likely around in registers for other users.
9407 (TV->hasOneUse() || FV->hasOneUse())) {
9408 Constant *Elts[] = {
9409 const_cast<ConstantFP*>(FV->getConstantFPValue()),
9410 const_cast<ConstantFP*>(TV->getConstantFPValue())
9411 };
Chris Lattnerdb125cf2011-07-18 04:54:35 +00009412 Type *FPTy = Elts[0]->getType();
Micah Villmow3574eca2012-10-08 16:38:25 +00009413 const DataLayout &TD = *TLI.getDataLayout();
Wesley Peckbf17cfa2010-11-23 03:31:01 +00009414
Chris Lattner600fec32009-03-11 05:08:08 +00009415 // Create a ConstantArray of the two constants.
Jay Foad26701082011-06-22 09:24:39 +00009416 Constant *CA = ConstantArray::get(ArrayType::get(FPTy, 2), Elts);
Chris Lattner600fec32009-03-11 05:08:08 +00009417 SDValue CPIdx = DAG.getConstantPool(CA, TLI.getPointerTy(),
9418 TD.getPrefTypeAlignment(FPTy));
Evan Cheng1606e8e2009-03-13 07:51:59 +00009419 unsigned Alignment = cast<ConstantPoolSDNode>(CPIdx)->getAlignment();
Chris Lattner600fec32009-03-11 05:08:08 +00009420
9421 // Get the offsets to the 0 and 1 element of the array so that we can
9422 // select between them.
9423 SDValue Zero = DAG.getIntPtrConstant(0);
Duncan Sands777d2302009-05-09 07:06:46 +00009424 unsigned EltSize = (unsigned)TD.getTypeAllocSize(Elts[0]->getType());
Chris Lattner600fec32009-03-11 05:08:08 +00009425 SDValue One = DAG.getIntPtrConstant(EltSize);
Wesley Peckbf17cfa2010-11-23 03:31:01 +00009426
Chris Lattner600fec32009-03-11 05:08:08 +00009427 SDValue Cond = DAG.getSetCC(DL,
9428 TLI.getSetCCResultType(N0.getValueType()),
9429 N0, N1, CC);
Dan Gohman7b316c92011-09-22 23:01:29 +00009430 AddToWorkList(Cond.getNode());
Chris Lattner600fec32009-03-11 05:08:08 +00009431 SDValue CstOffset = DAG.getNode(ISD::SELECT, DL, Zero.getValueType(),
9432 Cond, One, Zero);
Dan Gohman7b316c92011-09-22 23:01:29 +00009433 AddToWorkList(CstOffset.getNode());
Chris Lattner600fec32009-03-11 05:08:08 +00009434 CPIdx = DAG.getNode(ISD::ADD, DL, TLI.getPointerTy(), CPIdx,
9435 CstOffset);
Dan Gohman7b316c92011-09-22 23:01:29 +00009436 AddToWorkList(CPIdx.getNode());
Chris Lattner600fec32009-03-11 05:08:08 +00009437 return DAG.getLoad(TV->getValueType(0), DL, DAG.getEntryNode(), CPIdx,
Chris Lattner85ca1062010-09-21 07:32:19 +00009438 MachinePointerInfo::getConstantPool(), false,
Pete Cooperd752e0f2011-11-08 18:42:53 +00009439 false, false, Alignment);
Chris Lattner600fec32009-03-11 05:08:08 +00009440
9441 }
Wesley Peckbf17cfa2010-11-23 03:31:01 +00009442 }
Scott Michelfdc40a02009-02-17 22:15:04 +00009443
Nate Begemanf845b452005-10-08 00:29:44 +00009444 // Check to see if we can perform the "gzip trick", transforming
Bill Wendling836ca7d2009-01-30 23:59:18 +00009445 // (select_cc setlt X, 0, A, 0) -> (and (sra X, (sub size(X), 1), A)
Chris Lattnere3152e52006-09-20 06:41:35 +00009446 if (N1C && N3C && N3C->isNullValue() && CC == ISD::SETLT &&
Dan Gohman002e5d02008-03-13 22:13:53 +00009447 (N1C->isNullValue() || // (a < 0) ? b : 0
9448 (N1C->getAPIntValue() == 1 && N0 == N2))) { // (a < 1) ? a : 0
Owen Andersone50ed302009-08-10 22:56:29 +00009449 EVT XType = N0.getValueType();
9450 EVT AType = N2.getValueType();
Duncan Sands8e4eb092008-06-08 20:54:56 +00009451 if (XType.bitsGE(AType)) {
Sylvestre Ledru94c22712012-09-27 10:14:43 +00009452 // and (sra X, size(X)-1, A) -> "and (srl X, C2), A" iff A is a
Nate Begeman07ed4172005-10-10 21:26:48 +00009453 // single-bit constant.
Dan Gohman002e5d02008-03-13 22:13:53 +00009454 if (N2C && ((N2C->getAPIntValue() & (N2C->getAPIntValue()-1)) == 0)) {
9455 unsigned ShCtV = N2C->getAPIntValue().logBase2();
Duncan Sands83ec4b62008-06-06 12:08:01 +00009456 ShCtV = XType.getSizeInBits()-ShCtV-1;
Owen Anderson95771af2011-02-25 21:41:48 +00009457 SDValue ShCt = DAG.getConstant(ShCtV,
9458 getShiftAmountTy(N0.getValueType()));
Bill Wendling9729c5a2009-01-31 03:12:48 +00009459 SDValue Shift = DAG.getNode(ISD::SRL, N0.getDebugLoc(),
Bill Wendling836ca7d2009-01-30 23:59:18 +00009460 XType, N0, ShCt);
Gabor Greifba36cb52008-08-28 21:40:38 +00009461 AddToWorkList(Shift.getNode());
Bill Wendling836ca7d2009-01-30 23:59:18 +00009462
Duncan Sands8e4eb092008-06-08 20:54:56 +00009463 if (XType.bitsGT(AType)) {
Bill Wendling9729c5a2009-01-31 03:12:48 +00009464 Shift = DAG.getNode(ISD::TRUNCATE, DL, AType, Shift);
Gabor Greifba36cb52008-08-28 21:40:38 +00009465 AddToWorkList(Shift.getNode());
Nate Begemanf845b452005-10-08 00:29:44 +00009466 }
Bill Wendling836ca7d2009-01-30 23:59:18 +00009467
9468 return DAG.getNode(ISD::AND, DL, AType, Shift, N2);
Nate Begemanf845b452005-10-08 00:29:44 +00009469 }
Bill Wendling836ca7d2009-01-30 23:59:18 +00009470
Bill Wendling9729c5a2009-01-31 03:12:48 +00009471 SDValue Shift = DAG.getNode(ISD::SRA, N0.getDebugLoc(),
Bill Wendling836ca7d2009-01-30 23:59:18 +00009472 XType, N0,
9473 DAG.getConstant(XType.getSizeInBits()-1,
Owen Anderson95771af2011-02-25 21:41:48 +00009474 getShiftAmountTy(N0.getValueType())));
Gabor Greifba36cb52008-08-28 21:40:38 +00009475 AddToWorkList(Shift.getNode());
Bill Wendling836ca7d2009-01-30 23:59:18 +00009476
Duncan Sands8e4eb092008-06-08 20:54:56 +00009477 if (XType.bitsGT(AType)) {
Bill Wendling9729c5a2009-01-31 03:12:48 +00009478 Shift = DAG.getNode(ISD::TRUNCATE, DL, AType, Shift);
Gabor Greifba36cb52008-08-28 21:40:38 +00009479 AddToWorkList(Shift.getNode());
Nate Begemanf845b452005-10-08 00:29:44 +00009480 }
Bill Wendling836ca7d2009-01-30 23:59:18 +00009481
9482 return DAG.getNode(ISD::AND, DL, AType, Shift, N2);
Nate Begemanf845b452005-10-08 00:29:44 +00009483 }
9484 }
Scott Michelfdc40a02009-02-17 22:15:04 +00009485
Owen Andersoned1088a2010-09-22 22:58:22 +00009486 // fold (select_cc seteq (and x, y), 0, 0, A) -> (and (shr (shl x)) A)
9487 // where y is has a single bit set.
9488 // A plaintext description would be, we can turn the SELECT_CC into an AND
9489 // when the condition can be materialized as an all-ones register. Any
9490 // single bit-test can be materialized as an all-ones register with
9491 // shift-left and shift-right-arith.
9492 if (CC == ISD::SETEQ && N0->getOpcode() == ISD::AND &&
9493 N0->getValueType(0) == VT &&
Wesley Peckbf17cfa2010-11-23 03:31:01 +00009494 N1C && N1C->isNullValue() &&
Owen Andersoned1088a2010-09-22 22:58:22 +00009495 N2C && N2C->isNullValue()) {
9496 SDValue AndLHS = N0->getOperand(0);
9497 ConstantSDNode *ConstAndRHS = dyn_cast<ConstantSDNode>(N0->getOperand(1));
9498 if (ConstAndRHS && ConstAndRHS->getAPIntValue().countPopulation() == 1) {
9499 // Shift the tested bit over the sign bit.
9500 APInt AndMask = ConstAndRHS->getAPIntValue();
9501 SDValue ShlAmt =
Owen Anderson95771af2011-02-25 21:41:48 +00009502 DAG.getConstant(AndMask.countLeadingZeros(),
9503 getShiftAmountTy(AndLHS.getValueType()));
Owen Andersoned1088a2010-09-22 22:58:22 +00009504 SDValue Shl = DAG.getNode(ISD::SHL, N0.getDebugLoc(), VT, AndLHS, ShlAmt);
Wesley Peckbf17cfa2010-11-23 03:31:01 +00009505
Owen Andersoned1088a2010-09-22 22:58:22 +00009506 // Now arithmetic right shift it all the way over, so the result is either
9507 // all-ones, or zero.
9508 SDValue ShrAmt =
Owen Anderson95771af2011-02-25 21:41:48 +00009509 DAG.getConstant(AndMask.getBitWidth()-1,
9510 getShiftAmountTy(Shl.getValueType()));
Owen Andersoned1088a2010-09-22 22:58:22 +00009511 SDValue Shr = DAG.getNode(ISD::SRA, N0.getDebugLoc(), VT, Shl, ShrAmt);
Wesley Peckbf17cfa2010-11-23 03:31:01 +00009512
Owen Andersoned1088a2010-09-22 22:58:22 +00009513 return DAG.getNode(ISD::AND, DL, VT, Shr, N3);
9514 }
9515 }
9516
Nate Begeman07ed4172005-10-10 21:26:48 +00009517 // fold select C, 16, 0 -> shl C, 4
Dan Gohman002e5d02008-03-13 22:13:53 +00009518 if (N2C && N3C && N3C->isNullValue() && N2C->getAPIntValue().isPowerOf2() &&
Duncan Sands28b77e92011-09-06 19:07:46 +00009519 TLI.getBooleanContents(N0.getValueType().isVector()) ==
9520 TargetLowering::ZeroOrOneBooleanContent) {
Scott Michelfdc40a02009-02-17 22:15:04 +00009521
Chris Lattner1eba01e2007-04-11 06:50:51 +00009522 // If the caller doesn't want us to simplify this into a zext of a compare,
9523 // don't do it.
Dan Gohman002e5d02008-03-13 22:13:53 +00009524 if (NotExtCompare && N2C->getAPIntValue() == 1)
Dan Gohman475871a2008-07-27 21:46:04 +00009525 return SDValue();
Scott Michelfdc40a02009-02-17 22:15:04 +00009526
Nate Begeman07ed4172005-10-10 21:26:48 +00009527 // Get a SetCC of the condition
Owen Andersonefcc1ae2012-11-03 00:17:26 +00009528 // NOTE: Don't create a SETCC if it's not legal on this target.
9529 if (!LegalOperations ||
9530 TLI.isOperationLegal(ISD::SETCC,
9531 LegalTypes ? TLI.getSetCCResultType(N0.getValueType()) : MVT::i1)) {
9532 SDValue Temp, SCC;
9533 // cast from setcc result type to select result type
9534 if (LegalTypes) {
9535 SCC = DAG.getSetCC(DL, TLI.getSetCCResultType(N0.getValueType()),
9536 N0, N1, CC);
9537 if (N2.getValueType().bitsLT(SCC.getValueType()))
9538 Temp = DAG.getZeroExtendInReg(SCC, N2.getDebugLoc(),
9539 N2.getValueType());
9540 else
9541 Temp = DAG.getNode(ISD::ZERO_EXTEND, N2.getDebugLoc(),
9542 N2.getValueType(), SCC);
9543 } else {
9544 SCC = DAG.getSetCC(N0.getDebugLoc(), MVT::i1, N0, N1, CC);
Bill Wendling9729c5a2009-01-31 03:12:48 +00009545 Temp = DAG.getNode(ISD::ZERO_EXTEND, N2.getDebugLoc(),
Bill Wendling836ca7d2009-01-30 23:59:18 +00009546 N2.getValueType(), SCC);
Owen Andersonefcc1ae2012-11-03 00:17:26 +00009547 }
9548
9549 AddToWorkList(SCC.getNode());
9550 AddToWorkList(Temp.getNode());
9551
9552 if (N2C->getAPIntValue() == 1)
9553 return Temp;
9554
9555 // shl setcc result by log2 n2c
9556 return DAG.getNode(ISD::SHL, DL, N2.getValueType(), Temp,
9557 DAG.getConstant(N2C->getAPIntValue().logBase2(),
9558 getShiftAmountTy(Temp.getValueType())));
Nate Begemanb0d04a72006-02-18 02:40:58 +00009559 }
Nate Begeman07ed4172005-10-10 21:26:48 +00009560 }
Scott Michelfdc40a02009-02-17 22:15:04 +00009561
Nate Begemanf845b452005-10-08 00:29:44 +00009562 // Check to see if this is the equivalent of setcc
9563 // FIXME: Turn all of these into setcc if setcc if setcc is legal
9564 // otherwise, go ahead with the folds.
Dan Gohman002e5d02008-03-13 22:13:53 +00009565 if (0 && N3C && N3C->isNullValue() && N2C && (N2C->getAPIntValue() == 1ULL)) {
Owen Andersone50ed302009-08-10 22:56:29 +00009566 EVT XType = N0.getValueType();
Duncan Sands25cf2272008-11-24 14:53:14 +00009567 if (!LegalOperations ||
Duncan Sands5480c042009-01-01 15:52:00 +00009568 TLI.isOperationLegal(ISD::SETCC, TLI.getSetCCResultType(XType))) {
Bill Wendling836ca7d2009-01-30 23:59:18 +00009569 SDValue Res = DAG.getSetCC(DL, TLI.getSetCCResultType(XType), N0, N1, CC);
Nate Begemanf845b452005-10-08 00:29:44 +00009570 if (Res.getValueType() != VT)
Bill Wendling836ca7d2009-01-30 23:59:18 +00009571 Res = DAG.getNode(ISD::ZERO_EXTEND, DL, VT, Res);
Nate Begemanf845b452005-10-08 00:29:44 +00009572 return Res;
9573 }
Scott Michelfdc40a02009-02-17 22:15:04 +00009574
Bill Wendling836ca7d2009-01-30 23:59:18 +00009575 // fold (seteq X, 0) -> (srl (ctlz X, log2(size(X))))
Scott Michelfdc40a02009-02-17 22:15:04 +00009576 if (N1C && N1C->isNullValue() && CC == ISD::SETEQ &&
Duncan Sands25cf2272008-11-24 14:53:14 +00009577 (!LegalOperations ||
Duncan Sands184a8762008-06-14 17:48:34 +00009578 TLI.isOperationLegal(ISD::CTLZ, XType))) {
Bill Wendling9729c5a2009-01-31 03:12:48 +00009579 SDValue Ctlz = DAG.getNode(ISD::CTLZ, N0.getDebugLoc(), XType, N0);
Scott Michelfdc40a02009-02-17 22:15:04 +00009580 return DAG.getNode(ISD::SRL, DL, XType, Ctlz,
Duncan Sands83ec4b62008-06-06 12:08:01 +00009581 DAG.getConstant(Log2_32(XType.getSizeInBits()),
Owen Anderson95771af2011-02-25 21:41:48 +00009582 getShiftAmountTy(Ctlz.getValueType())));
Nate Begemanf845b452005-10-08 00:29:44 +00009583 }
Bill Wendling836ca7d2009-01-30 23:59:18 +00009584 // fold (setgt X, 0) -> (srl (and (-X, ~X), size(X)-1))
Scott Michelfdc40a02009-02-17 22:15:04 +00009585 if (N1C && N1C->isNullValue() && CC == ISD::SETGT) {
Bill Wendling836ca7d2009-01-30 23:59:18 +00009586 SDValue NegN0 = DAG.getNode(ISD::SUB, N0.getDebugLoc(),
9587 XType, DAG.getConstant(0, XType), N0);
Bill Wendling7581bfa2009-01-30 23:03:19 +00009588 SDValue NotN0 = DAG.getNOT(N0.getDebugLoc(), N0, XType);
Bill Wendling836ca7d2009-01-30 23:59:18 +00009589 return DAG.getNode(ISD::SRL, DL, XType,
Bill Wendlingfc4b6772009-02-01 11:19:36 +00009590 DAG.getNode(ISD::AND, DL, XType, NegN0, NotN0),
Duncan Sands83ec4b62008-06-06 12:08:01 +00009591 DAG.getConstant(XType.getSizeInBits()-1,
Owen Anderson95771af2011-02-25 21:41:48 +00009592 getShiftAmountTy(XType)));
Nate Begemanf845b452005-10-08 00:29:44 +00009593 }
Bill Wendling836ca7d2009-01-30 23:59:18 +00009594 // fold (setgt X, -1) -> (xor (srl (X, size(X)-1), 1))
Nate Begemanf845b452005-10-08 00:29:44 +00009595 if (N1C && N1C->isAllOnesValue() && CC == ISD::SETGT) {
Bill Wendling9729c5a2009-01-31 03:12:48 +00009596 SDValue Sign = DAG.getNode(ISD::SRL, N0.getDebugLoc(), XType, N0,
Bill Wendling836ca7d2009-01-30 23:59:18 +00009597 DAG.getConstant(XType.getSizeInBits()-1,
Owen Anderson95771af2011-02-25 21:41:48 +00009598 getShiftAmountTy(N0.getValueType())));
Bill Wendling836ca7d2009-01-30 23:59:18 +00009599 return DAG.getNode(ISD::XOR, DL, XType, Sign, DAG.getConstant(1, XType));
Nate Begemanf845b452005-10-08 00:29:44 +00009600 }
9601 }
Scott Michelfdc40a02009-02-17 22:15:04 +00009602
Benjamin Kramercde51102010-07-08 12:09:56 +00009603 // Check to see if this is an integer abs.
9604 // select_cc setg[te] X, 0, X, -X ->
9605 // select_cc setgt X, -1, X, -X ->
9606 // select_cc setl[te] X, 0, -X, X ->
9607 // select_cc setlt X, 1, -X, X ->
Nate Begemanf845b452005-10-08 00:29:44 +00009608 // Y = sra (X, size(X)-1); xor (add (X, Y), Y)
Benjamin Kramercde51102010-07-08 12:09:56 +00009609 if (N1C) {
9610 ConstantSDNode *SubC = NULL;
9611 if (((N1C->isNullValue() && (CC == ISD::SETGT || CC == ISD::SETGE)) ||
9612 (N1C->isAllOnesValue() && CC == ISD::SETGT)) &&
9613 N0 == N2 && N3.getOpcode() == ISD::SUB && N0 == N3.getOperand(1))
9614 SubC = dyn_cast<ConstantSDNode>(N3.getOperand(0));
9615 else if (((N1C->isNullValue() && (CC == ISD::SETLT || CC == ISD::SETLE)) ||
9616 (N1C->isOne() && CC == ISD::SETLT)) &&
9617 N0 == N3 && N2.getOpcode() == ISD::SUB && N0 == N2.getOperand(1))
9618 SubC = dyn_cast<ConstantSDNode>(N2.getOperand(0));
9619
Owen Andersone50ed302009-08-10 22:56:29 +00009620 EVT XType = N0.getValueType();
Benjamin Kramercde51102010-07-08 12:09:56 +00009621 if (SubC && SubC->isNullValue() && XType.isInteger()) {
9622 SDValue Shift = DAG.getNode(ISD::SRA, N0.getDebugLoc(), XType,
9623 N0,
9624 DAG.getConstant(XType.getSizeInBits()-1,
Owen Anderson95771af2011-02-25 21:41:48 +00009625 getShiftAmountTy(N0.getValueType())));
Benjamin Kramercde51102010-07-08 12:09:56 +00009626 SDValue Add = DAG.getNode(ISD::ADD, N0.getDebugLoc(),
9627 XType, N0, Shift);
9628 AddToWorkList(Shift.getNode());
9629 AddToWorkList(Add.getNode());
9630 return DAG.getNode(ISD::XOR, DL, XType, Add, Shift);
Nate Begemanf845b452005-10-08 00:29:44 +00009631 }
9632 }
Scott Michelfdc40a02009-02-17 22:15:04 +00009633
Dan Gohman475871a2008-07-27 21:46:04 +00009634 return SDValue();
Nate Begeman44728a72005-09-19 22:34:01 +00009635}
9636
Evan Chengfa1eb272007-02-08 22:13:59 +00009637/// SimplifySetCC - This is a stub for TargetLowering::SimplifySetCC.
Owen Andersone50ed302009-08-10 22:56:29 +00009638SDValue DAGCombiner::SimplifySetCC(EVT VT, SDValue N0,
Dan Gohman475871a2008-07-27 21:46:04 +00009639 SDValue N1, ISD::CondCode Cond,
Dale Johannesenff97d4f2009-02-03 00:47:48 +00009640 DebugLoc DL, bool foldBooleans) {
Scott Michelfdc40a02009-02-17 22:15:04 +00009641 TargetLowering::DAGCombinerInfo
Jakob Stoklund Olesen78d12642009-07-24 18:22:59 +00009642 DagCombineInfo(DAG, !LegalTypes, !LegalOperations, false, this);
Dale Johannesenff97d4f2009-02-03 00:47:48 +00009643 return TLI.SimplifySetCC(VT, N0, N1, Cond, foldBooleans, DagCombineInfo, DL);
Nate Begeman452d7beb2005-09-16 00:54:12 +00009644}
9645
Nate Begeman69575232005-10-20 02:15:44 +00009646/// BuildSDIVSequence - Given an ISD::SDIV node expressing a divide by constant,
9647/// return a DAG expression to select that will generate the same value by
9648/// multiplying by a magic number. See:
9649/// <http://the.wall.riscom.net/books/proc/ppc/cwg/code2.html>
Dan Gohman475871a2008-07-27 21:46:04 +00009650SDValue DAGCombiner::BuildSDIV(SDNode *N) {
Andrew Lenharth232c9102006-06-12 16:07:18 +00009651 std::vector<SDNode*> Built;
Richard Osborne19a4daf2011-11-07 17:09:05 +00009652 SDValue S = TLI.BuildSDIV(N, DAG, LegalOperations, &Built);
Andrew Lenharthdae9cbe2006-05-16 17:42:15 +00009653
Andrew Lenharth232c9102006-06-12 16:07:18 +00009654 for (std::vector<SDNode*>::iterator ii = Built.begin(), ee = Built.end();
Andrew Lenharthdae9cbe2006-05-16 17:42:15 +00009655 ii != ee; ++ii)
9656 AddToWorkList(*ii);
9657 return S;
Nate Begeman69575232005-10-20 02:15:44 +00009658}
9659
9660/// BuildUDIVSequence - Given an ISD::UDIV node expressing a divide by constant,
9661/// return a DAG expression to select that will generate the same value by
9662/// multiplying by a magic number. See:
9663/// <http://the.wall.riscom.net/books/proc/ppc/cwg/code2.html>
Dan Gohman475871a2008-07-27 21:46:04 +00009664SDValue DAGCombiner::BuildUDIV(SDNode *N) {
Andrew Lenharth232c9102006-06-12 16:07:18 +00009665 std::vector<SDNode*> Built;
Richard Osborne19a4daf2011-11-07 17:09:05 +00009666 SDValue S = TLI.BuildUDIV(N, DAG, LegalOperations, &Built);
Nate Begeman69575232005-10-20 02:15:44 +00009667
Andrew Lenharth232c9102006-06-12 16:07:18 +00009668 for (std::vector<SDNode*>::iterator ii = Built.begin(), ee = Built.end();
Andrew Lenharthdae9cbe2006-05-16 17:42:15 +00009669 ii != ee; ++ii)
9670 AddToWorkList(*ii);
9671 return S;
Nate Begeman69575232005-10-20 02:15:44 +00009672}
9673
Nate Begemancc66cdd2009-09-25 06:05:26 +00009674/// FindBaseOffset - Return true if base is a frame index, which is known not
Eric Christopher503a64d2010-12-09 04:48:06 +00009675// to alias with anything but itself. Provides base object and offset as
9676// results.
Nate Begemancc66cdd2009-09-25 06:05:26 +00009677static bool FindBaseOffset(SDValue Ptr, SDValue &Base, int64_t &Offset,
Roman Divacky2943e372012-09-05 22:15:49 +00009678 const GlobalValue *&GV, const void *&CV) {
Jim Laskey71382342006-10-07 23:37:56 +00009679 // Assume it is a primitive operation.
Nate Begemancc66cdd2009-09-25 06:05:26 +00009680 Base = Ptr; Offset = 0; GV = 0; CV = 0;
Scott Michelfdc40a02009-02-17 22:15:04 +00009681
Jim Laskey71382342006-10-07 23:37:56 +00009682 // If it's an adding a simple constant then integrate the offset.
9683 if (Base.getOpcode() == ISD::ADD) {
9684 if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Base.getOperand(1))) {
9685 Base = Base.getOperand(0);
Dan Gohmanf5aeb1a2008-09-12 16:56:44 +00009686 Offset += C->getZExtValue();
Jim Laskey71382342006-10-07 23:37:56 +00009687 }
9688 }
Wesley Peckbf17cfa2010-11-23 03:31:01 +00009689
Nate Begemancc66cdd2009-09-25 06:05:26 +00009690 // Return the underlying GlobalValue, and update the Offset. Return false
9691 // for GlobalAddressSDNode since the same GlobalAddress may be represented
9692 // by multiple nodes with different offsets.
9693 if (GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(Base)) {
9694 GV = G->getGlobal();
9695 Offset += G->getOffset();
9696 return false;
9697 }
Scott Michelfdc40a02009-02-17 22:15:04 +00009698
Nate Begemancc66cdd2009-09-25 06:05:26 +00009699 // Return the underlying Constant value, and update the Offset. Return false
9700 // for ConstantSDNodes since the same constant pool entry may be represented
9701 // by multiple nodes with different offsets.
9702 if (ConstantPoolSDNode *C = dyn_cast<ConstantPoolSDNode>(Base)) {
Roman Divacky2943e372012-09-05 22:15:49 +00009703 CV = C->isMachineConstantPoolEntry() ? (const void *)C->getMachineCPVal()
9704 : (const void *)C->getConstVal();
Nate Begemancc66cdd2009-09-25 06:05:26 +00009705 Offset += C->getOffset();
9706 return false;
9707 }
Jim Laskey71382342006-10-07 23:37:56 +00009708 // If it's any of the following then it can't alias with anything but itself.
Nate Begemancc66cdd2009-09-25 06:05:26 +00009709 return isa<FrameIndexSDNode>(Base);
Jim Laskey71382342006-10-07 23:37:56 +00009710}
9711
9712/// isAlias - Return true if there is any possibility that the two addresses
9713/// overlap.
Dan Gohman475871a2008-07-27 21:46:04 +00009714bool DAGCombiner::isAlias(SDValue Ptr1, int64_t Size1,
Jim Laskey096c22e2006-10-18 12:29:57 +00009715 const Value *SrcValue1, int SrcValueOffset1,
Nate Begemanb6aef5c2009-09-15 00:18:30 +00009716 unsigned SrcValueAlign1,
Dan Gohmanf96e4bd2010-10-20 00:31:05 +00009717 const MDNode *TBAAInfo1,
Dan Gohman475871a2008-07-27 21:46:04 +00009718 SDValue Ptr2, int64_t Size2,
Nate Begemanb6aef5c2009-09-15 00:18:30 +00009719 const Value *SrcValue2, int SrcValueOffset2,
Dan Gohmanf96e4bd2010-10-20 00:31:05 +00009720 unsigned SrcValueAlign2,
9721 const MDNode *TBAAInfo2) const {
Jim Laskey71382342006-10-07 23:37:56 +00009722 // If they are the same then they must be aliases.
9723 if (Ptr1 == Ptr2) return true;
Scott Michelfdc40a02009-02-17 22:15:04 +00009724
Jim Laskey71382342006-10-07 23:37:56 +00009725 // Gather base node and offset information.
Dan Gohman475871a2008-07-27 21:46:04 +00009726 SDValue Base1, Base2;
Jim Laskey71382342006-10-07 23:37:56 +00009727 int64_t Offset1, Offset2;
Dan Gohman46510a72010-04-15 01:51:59 +00009728 const GlobalValue *GV1, *GV2;
Roman Divacky2943e372012-09-05 22:15:49 +00009729 const void *CV1, *CV2;
Nate Begemancc66cdd2009-09-25 06:05:26 +00009730 bool isFrameIndex1 = FindBaseOffset(Ptr1, Base1, Offset1, GV1, CV1);
9731 bool isFrameIndex2 = FindBaseOffset(Ptr2, Base2, Offset2, GV2, CV2);
Scott Michelfdc40a02009-02-17 22:15:04 +00009732
Nate Begemancc66cdd2009-09-25 06:05:26 +00009733 // If they have a same base address then check to see if they overlap.
9734 if (Base1 == Base2 || (GV1 && (GV1 == GV2)) || (CV1 && (CV1 == CV2)))
Bill Wendling836ca7d2009-01-30 23:59:18 +00009735 return !((Offset1 + Size1) <= Offset2 || (Offset2 + Size2) <= Offset1);
Scott Michelfdc40a02009-02-17 22:15:04 +00009736
Owen Anderson4a9f1502010-09-20 20:39:59 +00009737 // It is possible for different frame indices to alias each other, mostly
9738 // when tail call optimization reuses return address slots for arguments.
9739 // To catch this case, look up the actual index of frame indices to compute
9740 // the real alias relationship.
9741 if (isFrameIndex1 && isFrameIndex2) {
9742 MachineFrameInfo *MFI = DAG.getMachineFunction().getFrameInfo();
9743 Offset1 += MFI->getObjectOffset(cast<FrameIndexSDNode>(Base1)->getIndex());
9744 Offset2 += MFI->getObjectOffset(cast<FrameIndexSDNode>(Base2)->getIndex());
9745 return !((Offset1 + Size1) <= Offset2 || (Offset2 + Size2) <= Offset1);
9746 }
9747
Wesley Peckbf17cfa2010-11-23 03:31:01 +00009748 // Otherwise, if we know what the bases are, and they aren't identical, then
Owen Anderson4a9f1502010-09-20 20:39:59 +00009749 // we know they cannot alias.
Nate Begemancc66cdd2009-09-25 06:05:26 +00009750 if ((isFrameIndex1 || CV1 || GV1) && (isFrameIndex2 || CV2 || GV2))
9751 return false;
Jim Laskey096c22e2006-10-18 12:29:57 +00009752
Nate Begemanb6aef5c2009-09-15 00:18:30 +00009753 // If we know required SrcValue1 and SrcValue2 have relatively large alignment
9754 // compared to the size and offset of the access, we may be able to prove they
9755 // do not alias. This check is conservative for now to catch cases created by
9756 // splitting vector types.
9757 if ((SrcValueAlign1 == SrcValueAlign2) &&
9758 (SrcValueOffset1 != SrcValueOffset2) &&
9759 (Size1 == Size2) && (SrcValueAlign1 > Size1)) {
9760 int64_t OffAlign1 = SrcValueOffset1 % SrcValueAlign1;
9761 int64_t OffAlign2 = SrcValueOffset2 % SrcValueAlign1;
Wesley Peckbf17cfa2010-11-23 03:31:01 +00009762
Nate Begemanb6aef5c2009-09-15 00:18:30 +00009763 // There is no overlap between these relatively aligned accesses of similar
9764 // size, return no alias.
9765 if ((OffAlign1 + Size1) <= OffAlign2 || (OffAlign2 + Size2) <= OffAlign1)
9766 return false;
9767 }
Wesley Peckbf17cfa2010-11-23 03:31:01 +00009768
Jim Laskey07a27092006-10-18 19:08:31 +00009769 if (CombinerGlobalAA) {
9770 // Use alias analysis information.
Dan Gohmane9c8fa02007-08-27 16:32:11 +00009771 int64_t MinOffset = std::min(SrcValueOffset1, SrcValueOffset2);
9772 int64_t Overlap1 = Size1 + SrcValueOffset1 - MinOffset;
9773 int64_t Overlap2 = Size2 + SrcValueOffset2 - MinOffset;
Scott Michelfdc40a02009-02-17 22:15:04 +00009774 AliasAnalysis::AliasResult AAResult =
Dan Gohmanf96e4bd2010-10-20 00:31:05 +00009775 AA.alias(AliasAnalysis::Location(SrcValue1, Overlap1, TBAAInfo1),
9776 AliasAnalysis::Location(SrcValue2, Overlap2, TBAAInfo2));
Jim Laskey07a27092006-10-18 19:08:31 +00009777 if (AAResult == AliasAnalysis::NoAlias)
9778 return false;
9779 }
Jim Laskey096c22e2006-10-18 12:29:57 +00009780
9781 // Otherwise we have to assume they alias.
9782 return true;
Jim Laskey71382342006-10-07 23:37:56 +00009783}
9784
Nadav Rotem90e11dc2012-11-29 00:00:08 +00009785bool DAGCombiner::isAlias(LSBaseSDNode *Op0, LSBaseSDNode *Op1) {
9786 SDValue Ptr0, Ptr1;
9787 int64_t Size0, Size1;
9788 const Value *SrcValue0, *SrcValue1;
9789 int SrcValueOffset0, SrcValueOffset1;
9790 unsigned SrcValueAlign0, SrcValueAlign1;
9791 const MDNode *SrcTBAAInfo0, *SrcTBAAInfo1;
9792 FindAliasInfo(Op0, Ptr0, Size0, SrcValue0, SrcValueOffset0,
9793 SrcValueAlign0, SrcTBAAInfo0);
9794 FindAliasInfo(Op1, Ptr1, Size1, SrcValue1, SrcValueOffset1,
9795 SrcValueAlign1, SrcTBAAInfo1);
9796 return isAlias(Ptr0, Size0, SrcValue0, SrcValueOffset0,
Nadav Rotemdde785c2012-12-06 17:34:13 +00009797 SrcValueAlign0, SrcTBAAInfo0,
9798 Ptr1, Size1, SrcValue1, SrcValueOffset1,
9799 SrcValueAlign1, SrcTBAAInfo1);
Nadav Rotem90e11dc2012-11-29 00:00:08 +00009800}
9801
Jim Laskey71382342006-10-07 23:37:56 +00009802/// FindAliasInfo - Extracts the relevant alias information from the memory
9803/// node. Returns true if the operand was a load.
Jim Laskey7ca56af2006-10-11 13:47:09 +00009804bool DAGCombiner::FindAliasInfo(SDNode *N,
Benjamin Kramerae4746b2012-01-15 11:50:43 +00009805 SDValue &Ptr, int64_t &Size,
9806 const Value *&SrcValue,
9807 int &SrcValueOffset,
9808 unsigned &SrcValueAlign,
9809 const MDNode *&TBAAInfo) const {
9810 LSBaseSDNode *LS = cast<LSBaseSDNode>(N);
9811
9812 Ptr = LS->getBasePtr();
9813 Size = LS->getMemoryVT().getSizeInBits() >> 3;
9814 SrcValue = LS->getSrcValue();
9815 SrcValueOffset = LS->getSrcValueOffset();
9816 SrcValueAlign = LS->getOriginalAlignment();
9817 TBAAInfo = LS->getTBAAInfo();
9818 return isa<LoadSDNode>(LS);
Jim Laskey71382342006-10-07 23:37:56 +00009819}
9820
Jim Laskey6ff23e52006-10-04 16:53:27 +00009821/// GatherAllAliases - Walk up chain skipping non-aliasing memory nodes,
9822/// looking for aliasing nodes and adding them to the Aliases vector.
Dan Gohman475871a2008-07-27 21:46:04 +00009823void DAGCombiner::GatherAllAliases(SDNode *N, SDValue OriginalChain,
9824 SmallVector<SDValue, 8> &Aliases) {
9825 SmallVector<SDValue, 8> Chains; // List of chains to visit.
Nate Begemanb6aef5c2009-09-15 00:18:30 +00009826 SmallPtrSet<SDNode *, 16> Visited; // Visited node set.
Scott Michelfdc40a02009-02-17 22:15:04 +00009827
Jim Laskey279f0532006-09-25 16:29:54 +00009828 // Get alias information for node.
Dan Gohman475871a2008-07-27 21:46:04 +00009829 SDValue Ptr;
Nate Begemanb6aef5c2009-09-15 00:18:30 +00009830 int64_t Size;
9831 const Value *SrcValue;
9832 int SrcValueOffset;
9833 unsigned SrcValueAlign;
Dan Gohmanf96e4bd2010-10-20 00:31:05 +00009834 const MDNode *SrcTBAAInfo;
Wesley Peckbf17cfa2010-11-23 03:31:01 +00009835 bool IsLoad = FindAliasInfo(N, Ptr, Size, SrcValue, SrcValueOffset,
Dan Gohmanf96e4bd2010-10-20 00:31:05 +00009836 SrcValueAlign, SrcTBAAInfo);
Jim Laskey279f0532006-09-25 16:29:54 +00009837
Jim Laskey6ff23e52006-10-04 16:53:27 +00009838 // Starting off.
Jim Laskeybc588b82006-10-05 15:07:25 +00009839 Chains.push_back(OriginalChain);
Nate Begeman677c89d2009-10-12 05:53:58 +00009840 unsigned Depth = 0;
Wesley Peckbf17cfa2010-11-23 03:31:01 +00009841
Jim Laskeybc588b82006-10-05 15:07:25 +00009842 // Look at each chain and determine if it is an alias. If so, add it to the
9843 // aliases list. If not, then continue up the chain looking for the next
Scott Michelfdc40a02009-02-17 22:15:04 +00009844 // candidate.
Jim Laskeybc588b82006-10-05 15:07:25 +00009845 while (!Chains.empty()) {
Dan Gohman475871a2008-07-27 21:46:04 +00009846 SDValue Chain = Chains.back();
Jim Laskeybc588b82006-10-05 15:07:25 +00009847 Chains.pop_back();
Wesley Peckbf17cfa2010-11-23 03:31:01 +00009848
9849 // For TokenFactor nodes, look at each operand and only continue up the
9850 // chain until we find two aliases. If we've seen two aliases, assume we'll
Nate Begeman677c89d2009-10-12 05:53:58 +00009851 // find more and revert to original chain since the xform is unlikely to be
9852 // profitable.
Wesley Peckbf17cfa2010-11-23 03:31:01 +00009853 //
9854 // FIXME: The depth check could be made to return the last non-aliasing
Nate Begeman677c89d2009-10-12 05:53:58 +00009855 // chain we found before we hit a tokenfactor rather than the original
9856 // chain.
9857 if (Depth > 6 || Aliases.size() == 2) {
9858 Aliases.clear();
9859 Aliases.push_back(OriginalChain);
9860 break;
9861 }
Scott Michelfdc40a02009-02-17 22:15:04 +00009862
Nate Begemanb6aef5c2009-09-15 00:18:30 +00009863 // Don't bother if we've been before.
9864 if (!Visited.insert(Chain.getNode()))
9865 continue;
Scott Michelfdc40a02009-02-17 22:15:04 +00009866
Jim Laskeybc588b82006-10-05 15:07:25 +00009867 switch (Chain.getOpcode()) {
9868 case ISD::EntryToken:
9869 // Entry token is ideal chain operand, but handled in FindBetterChain.
9870 break;
Scott Michelfdc40a02009-02-17 22:15:04 +00009871
Jim Laskeybc588b82006-10-05 15:07:25 +00009872 case ISD::LOAD:
9873 case ISD::STORE: {
9874 // Get alias information for Chain.
Dan Gohman475871a2008-07-27 21:46:04 +00009875 SDValue OpPtr;
Nate Begemanb6aef5c2009-09-15 00:18:30 +00009876 int64_t OpSize;
9877 const Value *OpSrcValue;
9878 int OpSrcValueOffset;
9879 unsigned OpSrcValueAlign;
Dan Gohmanf96e4bd2010-10-20 00:31:05 +00009880 const MDNode *OpSrcTBAAInfo;
Gabor Greifba36cb52008-08-28 21:40:38 +00009881 bool IsOpLoad = FindAliasInfo(Chain.getNode(), OpPtr, OpSize,
Nate Begemanb6aef5c2009-09-15 00:18:30 +00009882 OpSrcValue, OpSrcValueOffset,
Dan Gohmanf96e4bd2010-10-20 00:31:05 +00009883 OpSrcValueAlign,
9884 OpSrcTBAAInfo);
Scott Michelfdc40a02009-02-17 22:15:04 +00009885
Jim Laskeybc588b82006-10-05 15:07:25 +00009886 // If chain is alias then stop here.
9887 if (!(IsLoad && IsOpLoad) &&
Nate Begemanb6aef5c2009-09-15 00:18:30 +00009888 isAlias(Ptr, Size, SrcValue, SrcValueOffset, SrcValueAlign,
Dan Gohmanf96e4bd2010-10-20 00:31:05 +00009889 SrcTBAAInfo,
Nate Begemanb6aef5c2009-09-15 00:18:30 +00009890 OpPtr, OpSize, OpSrcValue, OpSrcValueOffset,
Dan Gohmanf96e4bd2010-10-20 00:31:05 +00009891 OpSrcValueAlign, OpSrcTBAAInfo)) {
Jim Laskeybc588b82006-10-05 15:07:25 +00009892 Aliases.push_back(Chain);
9893 } else {
9894 // Look further up the chain.
Scott Michelfdc40a02009-02-17 22:15:04 +00009895 Chains.push_back(Chain.getOperand(0));
Nate Begeman677c89d2009-10-12 05:53:58 +00009896 ++Depth;
Jim Laskey279f0532006-09-25 16:29:54 +00009897 }
Jim Laskeybc588b82006-10-05 15:07:25 +00009898 break;
9899 }
Scott Michelfdc40a02009-02-17 22:15:04 +00009900
Jim Laskeybc588b82006-10-05 15:07:25 +00009901 case ISD::TokenFactor:
Nate Begemanb6aef5c2009-09-15 00:18:30 +00009902 // We have to check each of the operands of the token factor for "small"
9903 // token factors, so we queue them up. Adding the operands to the queue
9904 // (stack) in reverse order maintains the original order and increases the
9905 // likelihood that getNode will find a matching token factor (CSE.)
9906 if (Chain.getNumOperands() > 16) {
9907 Aliases.push_back(Chain);
9908 break;
9909 }
Jim Laskeybc588b82006-10-05 15:07:25 +00009910 for (unsigned n = Chain.getNumOperands(); n;)
9911 Chains.push_back(Chain.getOperand(--n));
Nate Begeman677c89d2009-10-12 05:53:58 +00009912 ++Depth;
Jim Laskeybc588b82006-10-05 15:07:25 +00009913 break;
Scott Michelfdc40a02009-02-17 22:15:04 +00009914
Jim Laskeybc588b82006-10-05 15:07:25 +00009915 default:
9916 // For all other instructions we will just have to take what we can get.
9917 Aliases.push_back(Chain);
9918 break;
Jim Laskey279f0532006-09-25 16:29:54 +00009919 }
9920 }
Jim Laskey6ff23e52006-10-04 16:53:27 +00009921}
9922
9923/// FindBetterChain - Walk up chain skipping non-aliasing memory nodes, looking
9924/// for a better chain (aliasing node.)
Dan Gohman475871a2008-07-27 21:46:04 +00009925SDValue DAGCombiner::FindBetterChain(SDNode *N, SDValue OldChain) {
9926 SmallVector<SDValue, 8> Aliases; // Ops for replacing token factor.
Scott Michelfdc40a02009-02-17 22:15:04 +00009927
Jim Laskey6ff23e52006-10-04 16:53:27 +00009928 // Accumulate all the aliases to this node.
9929 GatherAllAliases(N, OldChain, Aliases);
Scott Michelfdc40a02009-02-17 22:15:04 +00009930
Dan Gohman71dc7c92011-05-17 22:20:36 +00009931 // If no operands then chain to entry token.
9932 if (Aliases.size() == 0)
Jim Laskey6ff23e52006-10-04 16:53:27 +00009933 return DAG.getEntryNode();
Dan Gohman71dc7c92011-05-17 22:20:36 +00009934
9935 // If a single operand then chain to it. We don't need to revisit it.
9936 if (Aliases.size() == 1)
Jim Laskey6ff23e52006-10-04 16:53:27 +00009937 return Aliases[0];
Wesley Peckbf17cfa2010-11-23 03:31:01 +00009938
Jim Laskey6ff23e52006-10-04 16:53:27 +00009939 // Construct a custom tailored token factor.
Wesley Peckbf17cfa2010-11-23 03:31:01 +00009940 return DAG.getNode(ISD::TokenFactor, N->getDebugLoc(), MVT::Other,
Nate Begemanb6aef5c2009-09-15 00:18:30 +00009941 &Aliases[0], Aliases.size());
Jim Laskey279f0532006-09-25 16:29:54 +00009942}
9943
Nate Begeman1d4d4142005-09-01 00:19:25 +00009944// SelectionDAG::Combine - This is the entry point for the file.
9945//
Bill Wendlingbe8cc2a2009-04-29 00:15:41 +00009946void SelectionDAG::Combine(CombineLevel Level, AliasAnalysis &AA,
Bill Wendling98a366d2009-04-29 23:29:43 +00009947 CodeGenOpt::Level OptLevel) {
Nate Begeman1d4d4142005-09-01 00:19:25 +00009948 /// run - This is the main entry point to this class.
9949 ///
Bill Wendlingbe8cc2a2009-04-29 00:15:41 +00009950 DAGCombiner(*this, AA, OptLevel).Run(Level);
Nate Begeman1d4d4142005-09-01 00:19:25 +00009951}