blob: 378c13b030171e308abe13f74d4c283bede76ddb [file] [log] [blame]
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 Lattner600fec32009-03-11 05:08:08 +000021#include "llvm/DerivedTypes.h"
Owen Andersona90b3dc2009-07-15 21:51:10 +000022#include "llvm/LLVMContext.h"
Chris Lattner00161a62008-01-25 07:20:16 +000023#include "llvm/CodeGen/MachineFunction.h"
24#include "llvm/CodeGen/MachineFrameInfo.h"
Chris Lattner600fec32009-03-11 05:08:08 +000025#include "llvm/CodeGen/PseudoSourceValue.h"
Chris Lattnerc76d4412007-05-16 06:37:59 +000026#include "llvm/Analysis/AliasAnalysis.h"
Evan Cheng59d5b682007-05-07 21:27:48 +000027#include "llvm/Target/TargetData.h"
Nate Begeman1d4d4142005-09-01 00:19:25 +000028#include "llvm/Target/TargetLowering.h"
Evan Cheng59d5b682007-05-07 21:27:48 +000029#include "llvm/Target/TargetMachine.h"
Chris Lattnerddae4bd2007-01-08 23:04:05 +000030#include "llvm/Target/TargetOptions.h"
Chris Lattnerc76d4412007-05-16 06:37:59 +000031#include "llvm/ADT/SmallPtrSet.h"
32#include "llvm/ADT/Statistic.h"
Jim Laskeyd1aed7a2006-09-21 16:28:59 +000033#include "llvm/Support/CommandLine.h"
Chris Lattnerc76d4412007-05-16 06:37:59 +000034#include "llvm/Support/Debug.h"
Torok Edwin7d696d82009-07-11 13:10:19 +000035#include "llvm/Support/ErrorHandling.h"
Chris Lattnerc76d4412007-05-16 06:37:59 +000036#include "llvm/Support/MathExtras.h"
Chris Lattnerbbbfa992009-08-23 06:35:02 +000037#include "llvm/Support/raw_ostream.h"
Chris Lattnera500fc62005-09-09 23:53:39 +000038#include <algorithm>
Nate Begeman1d4d4142005-09-01 00:19:25 +000039using namespace llvm;
40
Chris Lattnercd3245a2006-12-19 22:41:21 +000041STATISTIC(NodesCombined , "Number of dag nodes combined");
42STATISTIC(PreIndexedNodes , "Number of pre-indexed nodes created");
43STATISTIC(PostIndexedNodes, "Number of post-indexed nodes created");
Evan Cheng8b944d32009-05-28 00:35:15 +000044STATISTIC(OpsNarrowed , "Number of load/op/store narrowed");
Evan Cheng31959b12011-02-02 01:06:55 +000045STATISTIC(LdStFP2Int , "Number of fp load/store pairs transformed to int");
Chris Lattnercd3245a2006-12-19 22:41:21 +000046
Nate Begeman1d4d4142005-09-01 00:19:25 +000047namespace {
Jim Laskey71382342006-10-07 23:37:56 +000048 static cl::opt<bool>
Owen Anderson0dcc8142010-09-19 21:01:26 +000049 CombinerAA("combiner-alias-analysis", cl::Hidden,
Jim Laskey26f7fa72006-10-17 19:33:52 +000050 cl::desc("Turn on alias analysis during testing"));
Jim Laskey3ad175b2006-10-12 15:22:24 +000051
Jim Laskey07a27092006-10-18 19:08:31 +000052 static cl::opt<bool>
53 CombinerGlobalAA("combiner-global-alias-analysis", cl::Hidden,
54 cl::desc("Include global information in alias analysis"));
55
Jim Laskeybc588b82006-10-05 15:07:25 +000056//------------------------------ DAGCombiner ---------------------------------//
57
Nick Lewycky6726b6d2009-10-25 06:33:48 +000058 class DAGCombiner {
Nate Begeman1d4d4142005-09-01 00:19:25 +000059 SelectionDAG &DAG;
Dan Gohman79ce2762009-01-15 19:20:50 +000060 const TargetLowering &TLI;
Duncan Sands25cf2272008-11-24 14:53:14 +000061 CombineLevel Level;
Bill Wendling98a366d2009-04-29 23:29:43 +000062 CodeGenOpt::Level OptLevel;
Duncan Sands25cf2272008-11-24 14:53:14 +000063 bool LegalOperations;
64 bool LegalTypes;
Nate Begeman1d4d4142005-09-01 00:19:25 +000065
66 // Worklist of all of the nodes that need to be simplified.
Evan Cheng17a568b2008-08-29 22:21:44 +000067 std::vector<SDNode*> WorkList;
Nate Begeman1d4d4142005-09-01 00:19:25 +000068
Jim Laskeyc7c3f112006-10-16 20:52:31 +000069 // AA - Used for DAG load/store alias analysis.
70 AliasAnalysis &AA;
71
Nate Begeman1d4d4142005-09-01 00:19:25 +000072 /// AddUsersToWorkList - When an instruction is simplified, add all users of
73 /// the instruction to the work lists because they might get more simplified
74 /// now.
75 ///
76 void AddUsersToWorkList(SDNode *N) {
77 for (SDNode::use_iterator UI = N->use_begin(), UE = N->use_end();
Nate Begeman4ebd8052005-09-01 23:24:04 +000078 UI != UE; ++UI)
Dan Gohman89684502008-07-27 20:43:25 +000079 AddToWorkList(*UI);
Nate Begeman1d4d4142005-09-01 00:19:25 +000080 }
81
Dan Gohman389079b2007-10-08 17:57:15 +000082 /// visit - call the node-specific routine that knows how to fold each
83 /// particular type of node.
Dan Gohman475871a2008-07-27 21:46:04 +000084 SDValue visit(SDNode *N);
Dan Gohman389079b2007-10-08 17:57:15 +000085
Chris Lattner24664722006-03-01 04:53:38 +000086 public:
Jim Laskey6ff23e52006-10-04 16:53:27 +000087 /// AddToWorkList - Add to the work list making sure it's instance is at the
88 /// the back (next to be processed.)
Chris Lattner5750df92006-03-01 04:03:14 +000089 void AddToWorkList(SDNode *N) {
Jim Laskey6ff23e52006-10-04 16:53:27 +000090 removeFromWorkList(N);
Chris Lattner5750df92006-03-01 04:03:14 +000091 WorkList.push_back(N);
92 }
Jim Laskey6ff23e52006-10-04 16:53:27 +000093
Chris Lattnerf8dc0612008-02-03 06:49:24 +000094 /// removeFromWorkList - remove all instances of N from the worklist.
95 ///
96 void removeFromWorkList(SDNode *N) {
97 WorkList.erase(std::remove(WorkList.begin(), WorkList.end(), N),
98 WorkList.end());
Chris Lattner01a22022005-10-10 22:04:48 +000099 }
Scott Michelfdc40a02009-02-17 22:15:04 +0000100
Dan Gohman475871a2008-07-27 21:46:04 +0000101 SDValue CombineTo(SDNode *N, const SDValue *To, unsigned NumTo,
Evan Cheng0b0cd912009-03-28 05:57:29 +0000102 bool AddTo = true);
Scott Michelfdc40a02009-02-17 22:15:04 +0000103
Dan Gohman475871a2008-07-27 21:46:04 +0000104 SDValue CombineTo(SDNode *N, SDValue Res, bool AddTo = true) {
Jim Laskey274062c2006-10-13 23:32:28 +0000105 return CombineTo(N, &Res, 1, AddTo);
Chris Lattner24664722006-03-01 04:53:38 +0000106 }
Scott Michelfdc40a02009-02-17 22:15:04 +0000107
Dan Gohman475871a2008-07-27 21:46:04 +0000108 SDValue CombineTo(SDNode *N, SDValue Res0, SDValue Res1,
Evan Cheng0b0cd912009-03-28 05:57:29 +0000109 bool AddTo = true) {
Dan Gohman475871a2008-07-27 21:46:04 +0000110 SDValue To[] = { Res0, Res1 };
Jim Laskey274062c2006-10-13 23:32:28 +0000111 return CombineTo(N, To, 2, AddTo);
Chris Lattner24664722006-03-01 04:53:38 +0000112 }
Dan Gohmane5af2d32009-01-29 01:59:02 +0000113
114 void CommitTargetLoweringOpt(const TargetLowering::TargetLoweringOpt &TLO);
Scott Michelfdc40a02009-02-17 22:15:04 +0000115
116 private:
117
Chris Lattner012f2412006-02-17 21:58:01 +0000118 /// SimplifyDemandedBits - Check the specified integer node value to see if
Chris Lattnerb2742f42006-03-01 19:55:35 +0000119 /// it can be simplified or if things it uses can be simplified by bit
Chris Lattner012f2412006-02-17 21:58:01 +0000120 /// propagation. If so, return true.
Dan Gohman475871a2008-07-27 21:46:04 +0000121 bool SimplifyDemandedBits(SDValue Op) {
Dan Gohman87862e72009-12-11 21:31:27 +0000122 unsigned BitWidth = Op.getValueType().getScalarType().getSizeInBits();
123 APInt Demanded = APInt::getAllOnesValue(BitWidth);
Dan Gohman7b8d4a92008-02-27 00:25:32 +0000124 return SimplifyDemandedBits(Op, Demanded);
125 }
126
Dan Gohman475871a2008-07-27 21:46:04 +0000127 bool SimplifyDemandedBits(SDValue Op, const APInt &Demanded);
Chris Lattner87514ca2005-10-10 22:31:19 +0000128
Chris Lattner448f2192006-11-11 00:39:41 +0000129 bool CombineToPreIndexedLoadStore(SDNode *N);
130 bool CombineToPostIndexedLoadStore(SDNode *N);
Scott Michelfdc40a02009-02-17 22:15:04 +0000131
Evan Cheng95c57ea2010-04-24 04:43:44 +0000132 void ReplaceLoadWithPromotedLoad(SDNode *Load, SDNode *ExtLoad);
133 SDValue PromoteOperand(SDValue Op, EVT PVT, bool &Replace);
134 SDValue SExtPromoteOperand(SDValue Op, EVT PVT);
135 SDValue ZExtPromoteOperand(SDValue Op, EVT PVT);
Evan Cheng64b7bf72010-04-16 06:14:10 +0000136 SDValue PromoteIntBinOp(SDValue Op);
Evan Cheng07c4e102010-04-22 20:19:46 +0000137 SDValue PromoteIntShiftOp(SDValue Op);
Evan Cheng4c26e932010-04-19 19:29:22 +0000138 SDValue PromoteExtend(SDValue Op);
139 bool PromoteLoad(SDValue Op);
Scott Michelfdc40a02009-02-17 22:15:04 +0000140
Dan Gohman389079b2007-10-08 17:57:15 +0000141 /// combine - call the node-specific routine that knows how to fold each
142 /// particular type of node. If that doesn't do anything, try the
143 /// target-specific DAG combines.
Dan Gohman475871a2008-07-27 21:46:04 +0000144 SDValue combine(SDNode *N);
Nate Begeman1d4d4142005-09-01 00:19:25 +0000145
146 // Visitation implementation - Implement dag node combining for different
147 // node types. The semantics are as follows:
148 // Return Value:
Evan Cheng17a568b2008-08-29 22:21:44 +0000149 // SDValue.getNode() == 0 - No change was made
150 // SDValue.getNode() == N - N was replaced, is dead and has been handled.
151 // otherwise - N should be replaced by the returned Operand.
Nate Begeman1d4d4142005-09-01 00:19:25 +0000152 //
Dan Gohman475871a2008-07-27 21:46:04 +0000153 SDValue visitTokenFactor(SDNode *N);
154 SDValue visitMERGE_VALUES(SDNode *N);
155 SDValue visitADD(SDNode *N);
156 SDValue visitSUB(SDNode *N);
157 SDValue visitADDC(SDNode *N);
158 SDValue visitADDE(SDNode *N);
159 SDValue visitMUL(SDNode *N);
160 SDValue visitSDIV(SDNode *N);
161 SDValue visitUDIV(SDNode *N);
162 SDValue visitSREM(SDNode *N);
163 SDValue visitUREM(SDNode *N);
164 SDValue visitMULHU(SDNode *N);
165 SDValue visitMULHS(SDNode *N);
166 SDValue visitSMUL_LOHI(SDNode *N);
167 SDValue visitUMUL_LOHI(SDNode *N);
168 SDValue visitSDIVREM(SDNode *N);
169 SDValue visitUDIVREM(SDNode *N);
170 SDValue visitAND(SDNode *N);
171 SDValue visitOR(SDNode *N);
172 SDValue visitXOR(SDNode *N);
173 SDValue SimplifyVBinOp(SDNode *N);
174 SDValue visitSHL(SDNode *N);
175 SDValue visitSRA(SDNode *N);
176 SDValue visitSRL(SDNode *N);
177 SDValue visitCTLZ(SDNode *N);
178 SDValue visitCTTZ(SDNode *N);
179 SDValue visitCTPOP(SDNode *N);
180 SDValue visitSELECT(SDNode *N);
181 SDValue visitSELECT_CC(SDNode *N);
182 SDValue visitSETCC(SDNode *N);
183 SDValue visitSIGN_EXTEND(SDNode *N);
184 SDValue visitZERO_EXTEND(SDNode *N);
185 SDValue visitANY_EXTEND(SDNode *N);
186 SDValue visitSIGN_EXTEND_INREG(SDNode *N);
187 SDValue visitTRUNCATE(SDNode *N);
Wesley Peckbf17cfa2010-11-23 03:31:01 +0000188 SDValue visitBITCAST(SDNode *N);
Dan Gohman475871a2008-07-27 21:46:04 +0000189 SDValue visitBUILD_PAIR(SDNode *N);
190 SDValue visitFADD(SDNode *N);
191 SDValue visitFSUB(SDNode *N);
192 SDValue visitFMUL(SDNode *N);
193 SDValue visitFDIV(SDNode *N);
194 SDValue visitFREM(SDNode *N);
195 SDValue visitFCOPYSIGN(SDNode *N);
196 SDValue visitSINT_TO_FP(SDNode *N);
197 SDValue visitUINT_TO_FP(SDNode *N);
198 SDValue visitFP_TO_SINT(SDNode *N);
199 SDValue visitFP_TO_UINT(SDNode *N);
200 SDValue visitFP_ROUND(SDNode *N);
201 SDValue visitFP_ROUND_INREG(SDNode *N);
202 SDValue visitFP_EXTEND(SDNode *N);
203 SDValue visitFNEG(SDNode *N);
204 SDValue visitFABS(SDNode *N);
205 SDValue visitBRCOND(SDNode *N);
206 SDValue visitBR_CC(SDNode *N);
207 SDValue visitLOAD(SDNode *N);
208 SDValue visitSTORE(SDNode *N);
209 SDValue visitINSERT_VECTOR_ELT(SDNode *N);
210 SDValue visitEXTRACT_VECTOR_ELT(SDNode *N);
211 SDValue visitBUILD_VECTOR(SDNode *N);
212 SDValue visitCONCAT_VECTORS(SDNode *N);
213 SDValue visitVECTOR_SHUFFLE(SDNode *N);
Jim Grosbach9a526492010-06-23 16:07:42 +0000214 SDValue visitMEMBARRIER(SDNode *N);
Chris Lattner01a22022005-10-10 22:04:48 +0000215
Dan Gohman475871a2008-07-27 21:46:04 +0000216 SDValue XformToShuffleWithZero(SDNode *N);
Bill Wendling35247c32009-01-30 00:45:56 +0000217 SDValue ReassociateOps(unsigned Opc, DebugLoc DL, SDValue LHS, SDValue RHS);
Scott Michelfdc40a02009-02-17 22:15:04 +0000218
Dan Gohman475871a2008-07-27 21:46:04 +0000219 SDValue visitShiftByConstant(SDNode *N, unsigned Amt);
Chris Lattnere70da202007-12-06 07:33:36 +0000220
Dan Gohman475871a2008-07-27 21:46:04 +0000221 bool SimplifySelectOps(SDNode *SELECT, SDValue LHS, SDValue RHS);
222 SDValue SimplifyBinOpWithSameOpcodeHands(SDNode *N);
Bill Wendling836ca7d2009-01-30 23:59:18 +0000223 SDValue SimplifySelect(DebugLoc DL, SDValue N0, SDValue N1, SDValue N2);
Scott Michelfdc40a02009-02-17 22:15:04 +0000224 SDValue SimplifySelectCC(DebugLoc DL, SDValue N0, SDValue N1, SDValue N2,
225 SDValue N3, ISD::CondCode CC,
Bill Wendling836ca7d2009-01-30 23:59:18 +0000226 bool NotExtCompare = false);
Owen Andersone50ed302009-08-10 22:56:29 +0000227 SDValue SimplifySetCC(EVT VT, SDValue N0, SDValue N1, ISD::CondCode Cond,
Dale Johannesenff97d4f2009-02-03 00:47:48 +0000228 DebugLoc DL, bool foldBooleans = true);
Scott Michelfdc40a02009-02-17 22:15:04 +0000229 SDValue SimplifyNodeWithTwoResults(SDNode *N, unsigned LoOp,
Chris Lattner5eee4272008-01-26 01:09:19 +0000230 unsigned HiOp);
Owen Andersone50ed302009-08-10 22:56:29 +0000231 SDValue CombineConsecutiveLoads(SDNode *N, EVT VT);
Wesley Peckbf17cfa2010-11-23 03:31:01 +0000232 SDValue ConstantFoldBITCASTofBUILD_VECTOR(SDNode *, EVT);
Dan Gohman475871a2008-07-27 21:46:04 +0000233 SDValue BuildSDIV(SDNode *N);
234 SDValue BuildUDIV(SDNode *N);
Bill Wendling317bd702009-01-30 21:14:50 +0000235 SDNode *MatchRotate(SDValue LHS, SDValue RHS, DebugLoc DL);
Dan Gohman475871a2008-07-27 21:46:04 +0000236 SDValue ReduceLoadWidth(SDNode *N);
Evan Cheng8b944d32009-05-28 00:35:15 +0000237 SDValue ReduceLoadOpStoreWidth(SDNode *N);
Evan Cheng31959b12011-02-02 01:06:55 +0000238 SDValue TransformFPLoadStorePair(SDNode *N);
Scott Michelfdc40a02009-02-17 22:15:04 +0000239
Dan Gohman475871a2008-07-27 21:46:04 +0000240 SDValue GetDemandedBits(SDValue V, const APInt &Mask);
Scott Michelfdc40a02009-02-17 22:15:04 +0000241
Jim Laskey6ff23e52006-10-04 16:53:27 +0000242 /// GatherAllAliases - Walk up chain skipping non-aliasing memory nodes,
243 /// looking for aliasing nodes and adding them to the Aliases vector.
Dan Gohman475871a2008-07-27 21:46:04 +0000244 void GatherAllAliases(SDNode *N, SDValue OriginalChain,
245 SmallVector<SDValue, 8> &Aliases);
Jim Laskey6ff23e52006-10-04 16:53:27 +0000246
Jim Laskey096c22e2006-10-18 12:29:57 +0000247 /// isAlias - Return true if there is any possibility that the two addresses
248 /// overlap.
Dan Gohman475871a2008-07-27 21:46:04 +0000249 bool isAlias(SDValue Ptr1, int64_t Size1,
Jim Laskey096c22e2006-10-18 12:29:57 +0000250 const Value *SrcValue1, int SrcValueOffset1,
Nate Begemanb6aef5c2009-09-15 00:18:30 +0000251 unsigned SrcValueAlign1,
Dan Gohmanf96e4bd2010-10-20 00:31:05 +0000252 const MDNode *TBAAInfo1,
Dan Gohman475871a2008-07-27 21:46:04 +0000253 SDValue Ptr2, int64_t Size2,
Nate Begemanb6aef5c2009-09-15 00:18:30 +0000254 const Value *SrcValue2, int SrcValueOffset2,
Dan Gohmanf96e4bd2010-10-20 00:31:05 +0000255 unsigned SrcValueAlign2,
256 const MDNode *TBAAInfo2) const;
Scott Michelfdc40a02009-02-17 22:15:04 +0000257
Jim Laskey7ca56af2006-10-11 13:47:09 +0000258 /// FindAliasInfo - Extracts the relevant alias information from the memory
259 /// node. Returns true if the operand was a load.
260 bool FindAliasInfo(SDNode *N,
Dan Gohman475871a2008-07-27 21:46:04 +0000261 SDValue &Ptr, int64_t &Size,
Nate Begemanb6aef5c2009-09-15 00:18:30 +0000262 const Value *&SrcValue, int &SrcValueOffset,
Dan Gohmanf96e4bd2010-10-20 00:31:05 +0000263 unsigned &SrcValueAlignment,
264 const MDNode *&TBAAInfo) const;
Scott Michelfdc40a02009-02-17 22:15:04 +0000265
Jim Laskey279f0532006-09-25 16:29:54 +0000266 /// FindBetterChain - Walk up chain skipping non-aliasing memory nodes,
Jim Laskey6ff23e52006-10-04 16:53:27 +0000267 /// looking for a better chain (aliasing node.)
Dan Gohman475871a2008-07-27 21:46:04 +0000268 SDValue FindBetterChain(SDNode *N, SDValue Chain);
Duncan Sands92abc622009-01-31 15:50:11 +0000269
Chris Lattner2392ae72010-04-15 04:48:01 +0000270 public:
Bill Wendling98a366d2009-04-29 23:29:43 +0000271 DAGCombiner(SelectionDAG &D, AliasAnalysis &A, CodeGenOpt::Level OL)
Chris Lattner2392ae72010-04-15 04:48:01 +0000272 : DAG(D), TLI(D.getTargetLoweringInfo()), Level(Unrestricted),
273 OptLevel(OL), LegalOperations(false), LegalTypes(false), AA(A) {}
Scott Michelfdc40a02009-02-17 22:15:04 +0000274
Nate Begeman1d4d4142005-09-01 00:19:25 +0000275 /// Run - runs the dag combiner on all nodes in the work list
Duncan Sands25cf2272008-11-24 14:53:14 +0000276 void Run(CombineLevel AtLevel);
Wesley Peckbf17cfa2010-11-23 03:31:01 +0000277
Chris Lattner2392ae72010-04-15 04:48:01 +0000278 SelectionDAG &getDAG() const { return DAG; }
Wesley Peckbf17cfa2010-11-23 03:31:01 +0000279
Chris Lattner2392ae72010-04-15 04:48:01 +0000280 /// getShiftAmountTy - Returns a type large enough to hold any valid
281 /// shift amount - before type legalization these can be huge.
Owen Anderson95771af2011-02-25 21:41:48 +0000282 EVT getShiftAmountTy(EVT LHSTy) {
283 return LegalTypes ? TLI.getShiftAmountTy(LHSTy) : TLI.getPointerTy();
Chris Lattner2392ae72010-04-15 04:48:01 +0000284 }
Wesley Peckbf17cfa2010-11-23 03:31:01 +0000285
Chris Lattner2392ae72010-04-15 04:48:01 +0000286 /// isTypeLegal - This method returns true if we are running before type
287 /// legalization or if the specified VT is legal.
288 bool isTypeLegal(const EVT &VT) {
289 if (!LegalTypes) return true;
290 return TLI.isTypeLegal(VT);
291 }
Nate Begeman1d4d4142005-09-01 00:19:25 +0000292 };
293}
294
Chris Lattnerf8dc0612008-02-03 06:49:24 +0000295
296namespace {
297/// WorkListRemover - This class is a DAGUpdateListener that removes any deleted
298/// nodes from the worklist.
Nick Lewycky6726b6d2009-10-25 06:33:48 +0000299class WorkListRemover : public SelectionDAG::DAGUpdateListener {
Chris Lattnerf8dc0612008-02-03 06:49:24 +0000300 DAGCombiner &DC;
301public:
Dan Gohmanb5660dc2008-02-20 16:44:09 +0000302 explicit WorkListRemover(DAGCombiner &dc) : DC(dc) {}
Scott Michelfdc40a02009-02-17 22:15:04 +0000303
Duncan Sandsedfcf592008-06-11 11:42:12 +0000304 virtual void NodeDeleted(SDNode *N, SDNode *E) {
Chris Lattnerf8dc0612008-02-03 06:49:24 +0000305 DC.removeFromWorkList(N);
306 }
Scott Michelfdc40a02009-02-17 22:15:04 +0000307
Chris Lattnerf8dc0612008-02-03 06:49:24 +0000308 virtual void NodeUpdated(SDNode *N) {
309 // Ignore updates.
310 }
311};
312}
313
Chris Lattner24664722006-03-01 04:53:38 +0000314//===----------------------------------------------------------------------===//
315// TargetLowering::DAGCombinerInfo implementation
316//===----------------------------------------------------------------------===//
317
318void TargetLowering::DAGCombinerInfo::AddToWorklist(SDNode *N) {
319 ((DAGCombiner*)DC)->AddToWorkList(N);
320}
321
Cameron Zwariched3caf92011-04-02 02:40:26 +0000322void TargetLowering::DAGCombinerInfo::RemoveFromWorklist(SDNode *N) {
323 ((DAGCombiner*)DC)->removeFromWorkList(N);
324}
325
Dan Gohman475871a2008-07-27 21:46:04 +0000326SDValue TargetLowering::DAGCombinerInfo::
Evan Cheng0b0cd912009-03-28 05:57:29 +0000327CombineTo(SDNode *N, const std::vector<SDValue> &To, bool AddTo) {
328 return ((DAGCombiner*)DC)->CombineTo(N, &To[0], To.size(), AddTo);
Chris Lattner24664722006-03-01 04:53:38 +0000329}
330
Dan Gohman475871a2008-07-27 21:46:04 +0000331SDValue TargetLowering::DAGCombinerInfo::
Evan Cheng0b0cd912009-03-28 05:57:29 +0000332CombineTo(SDNode *N, SDValue Res, bool AddTo) {
333 return ((DAGCombiner*)DC)->CombineTo(N, Res, AddTo);
Chris Lattner24664722006-03-01 04:53:38 +0000334}
335
336
Dan Gohman475871a2008-07-27 21:46:04 +0000337SDValue TargetLowering::DAGCombinerInfo::
Evan Cheng0b0cd912009-03-28 05:57:29 +0000338CombineTo(SDNode *N, SDValue Res0, SDValue Res1, bool AddTo) {
339 return ((DAGCombiner*)DC)->CombineTo(N, Res0, Res1, AddTo);
Chris Lattner24664722006-03-01 04:53:38 +0000340}
341
Dan Gohmane5af2d32009-01-29 01:59:02 +0000342void TargetLowering::DAGCombinerInfo::
343CommitTargetLoweringOpt(const TargetLowering::TargetLoweringOpt &TLO) {
344 return ((DAGCombiner*)DC)->CommitTargetLoweringOpt(TLO);
345}
Chris Lattner24664722006-03-01 04:53:38 +0000346
Chris Lattner24664722006-03-01 04:53:38 +0000347//===----------------------------------------------------------------------===//
Chris Lattner29446522007-05-14 22:04:50 +0000348// Helper Functions
349//===----------------------------------------------------------------------===//
350
351/// isNegatibleForFree - Return 1 if we can compute the negated form of the
352/// specified expression for the same cost as the expression itself, or 2 if we
353/// can compute the negated form more cheaply than the expression itself.
Duncan Sands25cf2272008-11-24 14:53:14 +0000354static char isNegatibleForFree(SDValue Op, bool LegalOperations,
Chris Lattner0254e702008-02-26 07:04:54 +0000355 unsigned Depth = 0) {
Dale Johannesendb44bf82007-10-16 23:38:29 +0000356 // No compile time optimizations on this type.
Owen Anderson825b72b2009-08-11 20:47:22 +0000357 if (Op.getValueType() == MVT::ppcf128)
Dale Johannesendb44bf82007-10-16 23:38:29 +0000358 return 0;
359
Chris Lattner29446522007-05-14 22:04:50 +0000360 // fneg is removable even if it has multiple uses.
361 if (Op.getOpcode() == ISD::FNEG) return 2;
Scott Michelfdc40a02009-02-17 22:15:04 +0000362
Chris Lattner29446522007-05-14 22:04:50 +0000363 // Don't allow anything with multiple uses.
364 if (!Op.hasOneUse()) return 0;
Scott Michelfdc40a02009-02-17 22:15:04 +0000365
Chris Lattner3adf9512007-05-25 02:19:06 +0000366 // Don't recurse exponentially.
367 if (Depth > 6) return 0;
Scott Michelfdc40a02009-02-17 22:15:04 +0000368
Chris Lattner29446522007-05-14 22:04:50 +0000369 switch (Op.getOpcode()) {
370 default: return false;
371 case ISD::ConstantFP:
Chris Lattner0254e702008-02-26 07:04:54 +0000372 // Don't invert constant FP values after legalize. The negated constant
373 // isn't necessarily legal.
Duncan Sands25cf2272008-11-24 14:53:14 +0000374 return LegalOperations ? 0 : 1;
Chris Lattner29446522007-05-14 22:04:50 +0000375 case ISD::FADD:
376 // FIXME: determine better conditions for this xform.
377 if (!UnsafeFPMath) return 0;
Scott Michelfdc40a02009-02-17 22:15:04 +0000378
Bill Wendlingd34470c2009-01-30 23:10:18 +0000379 // fold (fsub (fadd A, B)) -> (fsub (fneg A), B)
Duncan Sands25cf2272008-11-24 14:53:14 +0000380 if (char V = isNegatibleForFree(Op.getOperand(0), LegalOperations, Depth+1))
Chris Lattner29446522007-05-14 22:04:50 +0000381 return V;
Bill Wendlingd34470c2009-01-30 23:10:18 +0000382 // fold (fneg (fadd A, B)) -> (fsub (fneg B), A)
Duncan Sands25cf2272008-11-24 14:53:14 +0000383 return isNegatibleForFree(Op.getOperand(1), LegalOperations, Depth+1);
Chris Lattner29446522007-05-14 22:04:50 +0000384 case ISD::FSUB:
Scott Michelfdc40a02009-02-17 22:15:04 +0000385 // We can't turn -(A-B) into B-A when we honor signed zeros.
Chris Lattner29446522007-05-14 22:04:50 +0000386 if (!UnsafeFPMath) return 0;
Scott Michelfdc40a02009-02-17 22:15:04 +0000387
Bill Wendlingd34470c2009-01-30 23:10:18 +0000388 // fold (fneg (fsub A, B)) -> (fsub B, A)
Chris Lattner29446522007-05-14 22:04:50 +0000389 return 1;
Scott Michelfdc40a02009-02-17 22:15:04 +0000390
Chris Lattner29446522007-05-14 22:04:50 +0000391 case ISD::FMUL:
392 case ISD::FDIV:
393 if (HonorSignDependentRoundingFPMath()) return 0;
Scott Michelfdc40a02009-02-17 22:15:04 +0000394
Bill Wendlingd34470c2009-01-30 23:10:18 +0000395 // fold (fneg (fmul X, Y)) -> (fmul (fneg X), Y) or (fmul X, (fneg Y))
Duncan Sands25cf2272008-11-24 14:53:14 +0000396 if (char V = isNegatibleForFree(Op.getOperand(0), LegalOperations, Depth+1))
Chris Lattner29446522007-05-14 22:04:50 +0000397 return V;
Scott Michelfdc40a02009-02-17 22:15:04 +0000398
Duncan Sands25cf2272008-11-24 14:53:14 +0000399 return isNegatibleForFree(Op.getOperand(1), LegalOperations, Depth+1);
Scott Michelfdc40a02009-02-17 22:15:04 +0000400
Chris Lattner29446522007-05-14 22:04:50 +0000401 case ISD::FP_EXTEND:
402 case ISD::FP_ROUND:
403 case ISD::FSIN:
Duncan Sands25cf2272008-11-24 14:53:14 +0000404 return isNegatibleForFree(Op.getOperand(0), LegalOperations, Depth+1);
Chris Lattner29446522007-05-14 22:04:50 +0000405 }
406}
407
408/// GetNegatedExpression - If isNegatibleForFree returns true, this function
409/// returns the newly negated expression.
Dan Gohman475871a2008-07-27 21:46:04 +0000410static SDValue GetNegatedExpression(SDValue Op, SelectionDAG &DAG,
Duncan Sands25cf2272008-11-24 14:53:14 +0000411 bool LegalOperations, unsigned Depth = 0) {
Chris Lattner29446522007-05-14 22:04:50 +0000412 // fneg is removable even if it has multiple uses.
413 if (Op.getOpcode() == ISD::FNEG) return Op.getOperand(0);
Scott Michelfdc40a02009-02-17 22:15:04 +0000414
Chris Lattner29446522007-05-14 22:04:50 +0000415 // Don't allow anything with multiple uses.
416 assert(Op.hasOneUse() && "Unknown reuse!");
Scott Michelfdc40a02009-02-17 22:15:04 +0000417
Chris Lattner3adf9512007-05-25 02:19:06 +0000418 assert(Depth <= 6 && "GetNegatedExpression doesn't match isNegatibleForFree");
Chris Lattner29446522007-05-14 22:04:50 +0000419 switch (Op.getOpcode()) {
Torok Edwinc23197a2009-07-14 16:55:14 +0000420 default: llvm_unreachable("Unknown code");
Dale Johannesenc4dd3c32007-08-31 23:34:27 +0000421 case ISD::ConstantFP: {
422 APFloat V = cast<ConstantFPSDNode>(Op)->getValueAPF();
423 V.changeSign();
424 return DAG.getConstantFP(V, Op.getValueType());
425 }
Chris Lattner29446522007-05-14 22:04:50 +0000426 case ISD::FADD:
427 // FIXME: determine better conditions for this xform.
428 assert(UnsafeFPMath);
Scott Michelfdc40a02009-02-17 22:15:04 +0000429
Bill Wendlingd34470c2009-01-30 23:10:18 +0000430 // fold (fneg (fadd A, B)) -> (fsub (fneg A), B)
Duncan Sands25cf2272008-11-24 14:53:14 +0000431 if (isNegatibleForFree(Op.getOperand(0), LegalOperations, Depth+1))
Bill Wendling35247c32009-01-30 00:45:56 +0000432 return DAG.getNode(ISD::FSUB, Op.getDebugLoc(), Op.getValueType(),
Scott Michelfdc40a02009-02-17 22:15:04 +0000433 GetNegatedExpression(Op.getOperand(0), DAG,
Duncan Sands25cf2272008-11-24 14:53:14 +0000434 LegalOperations, Depth+1),
Chris Lattner29446522007-05-14 22:04:50 +0000435 Op.getOperand(1));
Bill Wendlingd34470c2009-01-30 23:10:18 +0000436 // fold (fneg (fadd A, B)) -> (fsub (fneg B), A)
Bill Wendling35247c32009-01-30 00:45:56 +0000437 return DAG.getNode(ISD::FSUB, Op.getDebugLoc(), Op.getValueType(),
Scott Michelfdc40a02009-02-17 22:15:04 +0000438 GetNegatedExpression(Op.getOperand(1), DAG,
Duncan Sands25cf2272008-11-24 14:53:14 +0000439 LegalOperations, Depth+1),
Chris Lattner29446522007-05-14 22:04:50 +0000440 Op.getOperand(0));
441 case ISD::FSUB:
Scott Michelfdc40a02009-02-17 22:15:04 +0000442 // We can't turn -(A-B) into B-A when we honor signed zeros.
Chris Lattner29446522007-05-14 22:04:50 +0000443 assert(UnsafeFPMath);
Dan Gohman23ff1822007-07-02 15:48:56 +0000444
Bill Wendlingd34470c2009-01-30 23:10:18 +0000445 // fold (fneg (fsub 0, B)) -> B
Dan Gohman23ff1822007-07-02 15:48:56 +0000446 if (ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(Op.getOperand(0)))
Dale Johannesenc4dd3c32007-08-31 23:34:27 +0000447 if (N0CFP->getValueAPF().isZero())
Dan Gohman23ff1822007-07-02 15:48:56 +0000448 return Op.getOperand(1);
Scott Michelfdc40a02009-02-17 22:15:04 +0000449
Bill Wendlingd34470c2009-01-30 23:10:18 +0000450 // fold (fneg (fsub A, B)) -> (fsub B, A)
Bill Wendling35247c32009-01-30 00:45:56 +0000451 return DAG.getNode(ISD::FSUB, Op.getDebugLoc(), Op.getValueType(),
452 Op.getOperand(1), Op.getOperand(0));
Scott Michelfdc40a02009-02-17 22:15:04 +0000453
Chris Lattner29446522007-05-14 22:04:50 +0000454 case ISD::FMUL:
455 case ISD::FDIV:
456 assert(!HonorSignDependentRoundingFPMath());
Scott Michelfdc40a02009-02-17 22:15:04 +0000457
Bill Wendlingd34470c2009-01-30 23:10:18 +0000458 // fold (fneg (fmul X, Y)) -> (fmul (fneg X), Y)
Duncan Sands25cf2272008-11-24 14:53:14 +0000459 if (isNegatibleForFree(Op.getOperand(0), LegalOperations, Depth+1))
Bill Wendling35247c32009-01-30 00:45:56 +0000460 return DAG.getNode(Op.getOpcode(), Op.getDebugLoc(), Op.getValueType(),
Scott Michelfdc40a02009-02-17 22:15:04 +0000461 GetNegatedExpression(Op.getOperand(0), DAG,
Duncan Sands25cf2272008-11-24 14:53:14 +0000462 LegalOperations, Depth+1),
Chris Lattner29446522007-05-14 22:04:50 +0000463 Op.getOperand(1));
Scott Michelfdc40a02009-02-17 22:15:04 +0000464
Bill Wendlingd34470c2009-01-30 23:10:18 +0000465 // fold (fneg (fmul X, Y)) -> (fmul X, (fneg Y))
Bill Wendling35247c32009-01-30 00:45:56 +0000466 return DAG.getNode(Op.getOpcode(), Op.getDebugLoc(), Op.getValueType(),
Chris Lattner29446522007-05-14 22:04:50 +0000467 Op.getOperand(0),
Chris Lattner0254e702008-02-26 07:04:54 +0000468 GetNegatedExpression(Op.getOperand(1), DAG,
Duncan Sands25cf2272008-11-24 14:53:14 +0000469 LegalOperations, Depth+1));
Scott Michelfdc40a02009-02-17 22:15:04 +0000470
Chris Lattner29446522007-05-14 22:04:50 +0000471 case ISD::FP_EXTEND:
Chris Lattner29446522007-05-14 22:04:50 +0000472 case ISD::FSIN:
Bill Wendling35247c32009-01-30 00:45:56 +0000473 return DAG.getNode(Op.getOpcode(), Op.getDebugLoc(), Op.getValueType(),
Scott Michelfdc40a02009-02-17 22:15:04 +0000474 GetNegatedExpression(Op.getOperand(0), DAG,
Duncan Sands25cf2272008-11-24 14:53:14 +0000475 LegalOperations, Depth+1));
Chris Lattner0bd48932008-01-17 07:00:52 +0000476 case ISD::FP_ROUND:
Bill Wendling35247c32009-01-30 00:45:56 +0000477 return DAG.getNode(ISD::FP_ROUND, Op.getDebugLoc(), Op.getValueType(),
Scott Michelfdc40a02009-02-17 22:15:04 +0000478 GetNegatedExpression(Op.getOperand(0), DAG,
Duncan Sands25cf2272008-11-24 14:53:14 +0000479 LegalOperations, Depth+1),
Chris Lattner0bd48932008-01-17 07:00:52 +0000480 Op.getOperand(1));
Chris Lattner29446522007-05-14 22:04:50 +0000481 }
482}
Chris Lattner24664722006-03-01 04:53:38 +0000483
484
Nate Begeman4ebd8052005-09-01 23:24:04 +0000485// isSetCCEquivalent - Return true if this node is a setcc, or is a select_cc
486// that selects between the values 1 and 0, making it equivalent to a setcc.
Scott Michelfdc40a02009-02-17 22:15:04 +0000487// Also, set the incoming LHS, RHS, and CC references to the appropriate
Nate Begeman646d7e22005-09-02 21:18:40 +0000488// nodes based on the type of node we are checking. This simplifies life a
489// bit for the callers.
Dan Gohman475871a2008-07-27 21:46:04 +0000490static bool isSetCCEquivalent(SDValue N, SDValue &LHS, SDValue &RHS,
491 SDValue &CC) {
Nate Begeman646d7e22005-09-02 21:18:40 +0000492 if (N.getOpcode() == ISD::SETCC) {
493 LHS = N.getOperand(0);
494 RHS = N.getOperand(1);
495 CC = N.getOperand(2);
Nate Begeman4ebd8052005-09-01 23:24:04 +0000496 return true;
Nate Begeman646d7e22005-09-02 21:18:40 +0000497 }
Scott Michelfdc40a02009-02-17 22:15:04 +0000498 if (N.getOpcode() == ISD::SELECT_CC &&
Nate Begeman1d4d4142005-09-01 00:19:25 +0000499 N.getOperand(2).getOpcode() == ISD::Constant &&
500 N.getOperand(3).getOpcode() == ISD::Constant &&
Dan Gohman002e5d02008-03-13 22:13:53 +0000501 cast<ConstantSDNode>(N.getOperand(2))->getAPIntValue() == 1 &&
Nate Begeman646d7e22005-09-02 21:18:40 +0000502 cast<ConstantSDNode>(N.getOperand(3))->isNullValue()) {
503 LHS = N.getOperand(0);
504 RHS = N.getOperand(1);
505 CC = N.getOperand(4);
Nate Begeman1d4d4142005-09-01 00:19:25 +0000506 return true;
Nate Begeman646d7e22005-09-02 21:18:40 +0000507 }
Nate Begeman1d4d4142005-09-01 00:19:25 +0000508 return false;
509}
510
Nate Begeman99801192005-09-07 23:25:52 +0000511// isOneUseSetCC - Return true if this is a SetCC-equivalent operation with only
512// one use. If this is true, it allows the users to invert the operation for
513// free when it is profitable to do so.
Dan Gohman475871a2008-07-27 21:46:04 +0000514static bool isOneUseSetCC(SDValue N) {
515 SDValue N0, N1, N2;
Gabor Greifba36cb52008-08-28 21:40:38 +0000516 if (isSetCCEquivalent(N, N0, N1, N2) && N.getNode()->hasOneUse())
Nate Begeman4ebd8052005-09-01 23:24:04 +0000517 return true;
518 return false;
519}
520
Bill Wendling35247c32009-01-30 00:45:56 +0000521SDValue DAGCombiner::ReassociateOps(unsigned Opc, DebugLoc DL,
522 SDValue N0, SDValue N1) {
Owen Andersone50ed302009-08-10 22:56:29 +0000523 EVT VT = N0.getValueType();
Nate Begemancd4d58c2006-02-03 06:46:56 +0000524 if (N0.getOpcode() == Opc && isa<ConstantSDNode>(N0.getOperand(1))) {
525 if (isa<ConstantSDNode>(N1)) {
Bill Wendling35247c32009-01-30 00:45:56 +0000526 // reassoc. (op (op x, c1), c2) -> (op x, (op c1, c2))
Bill Wendling6af76182009-01-30 20:50:00 +0000527 SDValue OpNode =
528 DAG.FoldConstantArithmetic(Opc, VT,
529 cast<ConstantSDNode>(N0.getOperand(1)),
530 cast<ConstantSDNode>(N1));
Bill Wendlingd69c3142009-01-30 02:23:43 +0000531 return DAG.getNode(Opc, DL, VT, N0.getOperand(0), OpNode);
Nate Begemancd4d58c2006-02-03 06:46:56 +0000532 } else if (N0.hasOneUse()) {
Bill Wendling35247c32009-01-30 00:45:56 +0000533 // reassoc. (op (op x, c1), y) -> (op (op x, y), c1) iff x+c1 has one use
534 SDValue OpNode = DAG.getNode(Opc, N0.getDebugLoc(), VT,
535 N0.getOperand(0), N1);
Gabor Greifba36cb52008-08-28 21:40:38 +0000536 AddToWorkList(OpNode.getNode());
Bill Wendling35247c32009-01-30 00:45:56 +0000537 return DAG.getNode(Opc, DL, VT, OpNode, N0.getOperand(1));
Nate Begemancd4d58c2006-02-03 06:46:56 +0000538 }
539 }
Bill Wendling35247c32009-01-30 00:45:56 +0000540
Nate Begemancd4d58c2006-02-03 06:46:56 +0000541 if (N1.getOpcode() == Opc && isa<ConstantSDNode>(N1.getOperand(1))) {
542 if (isa<ConstantSDNode>(N0)) {
Bill Wendling35247c32009-01-30 00:45:56 +0000543 // reassoc. (op c2, (op x, c1)) -> (op x, (op c1, c2))
Bill Wendling6af76182009-01-30 20:50:00 +0000544 SDValue OpNode =
545 DAG.FoldConstantArithmetic(Opc, VT,
546 cast<ConstantSDNode>(N1.getOperand(1)),
547 cast<ConstantSDNode>(N0));
Bill Wendlingd69c3142009-01-30 02:23:43 +0000548 return DAG.getNode(Opc, DL, VT, N1.getOperand(0), OpNode);
Nate Begemancd4d58c2006-02-03 06:46:56 +0000549 } else if (N1.hasOneUse()) {
Bill Wendling35247c32009-01-30 00:45:56 +0000550 // reassoc. (op y, (op x, c1)) -> (op (op x, y), c1) iff x+c1 has one use
Bill Wendlingd69c3142009-01-30 02:23:43 +0000551 SDValue OpNode = DAG.getNode(Opc, N0.getDebugLoc(), VT,
Bill Wendling35247c32009-01-30 00:45:56 +0000552 N1.getOperand(0), N0);
Gabor Greifba36cb52008-08-28 21:40:38 +0000553 AddToWorkList(OpNode.getNode());
Bill Wendling35247c32009-01-30 00:45:56 +0000554 return DAG.getNode(Opc, DL, VT, OpNode, N1.getOperand(1));
Nate Begemancd4d58c2006-02-03 06:46:56 +0000555 }
556 }
Bill Wendling35247c32009-01-30 00:45:56 +0000557
Dan Gohman475871a2008-07-27 21:46:04 +0000558 return SDValue();
Nate Begemancd4d58c2006-02-03 06:46:56 +0000559}
560
Dan Gohman475871a2008-07-27 21:46:04 +0000561SDValue DAGCombiner::CombineTo(SDNode *N, const SDValue *To, unsigned NumTo,
562 bool AddTo) {
Chris Lattnerf8dc0612008-02-03 06:49:24 +0000563 assert(N->getNumValues() == NumTo && "Broken CombineTo call!");
564 ++NodesCombined;
David Greenef1090292010-01-05 01:25:00 +0000565 DEBUG(dbgs() << "\nReplacing.1 ";
Chris Lattnerbbbfa992009-08-23 06:35:02 +0000566 N->dump(&DAG);
David Greenef1090292010-01-05 01:25:00 +0000567 dbgs() << "\nWith: ";
Chris Lattnerbbbfa992009-08-23 06:35:02 +0000568 To[0].getNode()->dump(&DAG);
David Greenef1090292010-01-05 01:25:00 +0000569 dbgs() << " and " << NumTo-1 << " other values\n";
Chris Lattnerbbbfa992009-08-23 06:35:02 +0000570 for (unsigned i = 0, e = NumTo; i != e; ++i)
Jakob Stoklund Olesen9f0d4e62009-12-03 05:15:35 +0000571 assert((!To[i].getNode() ||
572 N->getValueType(i) == To[i].getValueType()) &&
Dan Gohman764fd0c2009-01-21 15:17:51 +0000573 "Cannot combine value to value of different type!"));
Chris Lattnerf8dc0612008-02-03 06:49:24 +0000574 WorkListRemover DeadNodes(*this);
575 DAG.ReplaceAllUsesWith(N, To, &DeadNodes);
Scott Michelfdc40a02009-02-17 22:15:04 +0000576
Chris Lattnerf8dc0612008-02-03 06:49:24 +0000577 if (AddTo) {
578 // Push the new nodes and any users onto the worklist
579 for (unsigned i = 0, e = NumTo; i != e; ++i) {
Chris Lattnerd1980a52009-03-12 06:52:53 +0000580 if (To[i].getNode()) {
581 AddToWorkList(To[i].getNode());
582 AddUsersToWorkList(To[i].getNode());
583 }
Chris Lattnerf8dc0612008-02-03 06:49:24 +0000584 }
585 }
Scott Michelfdc40a02009-02-17 22:15:04 +0000586
Dan Gohmandbe664a2009-01-19 21:44:21 +0000587 // Finally, if the node is now dead, remove it from the graph. The node
588 // may not be dead if the replacement process recursively simplified to
589 // something else needing this node.
590 if (N->use_empty()) {
591 // Nodes can be reintroduced into the worklist. Make sure we do not
592 // process a node that has been replaced.
593 removeFromWorkList(N);
Scott Michelfdc40a02009-02-17 22:15:04 +0000594
Dan Gohmandbe664a2009-01-19 21:44:21 +0000595 // Finally, since the node is now dead, remove it from the graph.
596 DAG.DeleteNode(N);
597 }
Dan Gohman475871a2008-07-27 21:46:04 +0000598 return SDValue(N, 0);
Chris Lattnerf8dc0612008-02-03 06:49:24 +0000599}
600
Evan Chenge5b51ac2010-04-17 06:13:15 +0000601void DAGCombiner::
602CommitTargetLoweringOpt(const TargetLowering::TargetLoweringOpt &TLO) {
Scott Michelfdc40a02009-02-17 22:15:04 +0000603 // Replace all uses. If any nodes become isomorphic to other nodes and
Chris Lattnerf8dc0612008-02-03 06:49:24 +0000604 // are deleted, make sure to remove them from our worklist.
605 WorkListRemover DeadNodes(*this);
606 DAG.ReplaceAllUsesOfValueWith(TLO.Old, TLO.New, &DeadNodes);
Dan Gohmane5af2d32009-01-29 01:59:02 +0000607
Chris Lattnerf8dc0612008-02-03 06:49:24 +0000608 // Push the new node and any (possibly new) users onto the worklist.
Gabor Greifba36cb52008-08-28 21:40:38 +0000609 AddToWorkList(TLO.New.getNode());
610 AddUsersToWorkList(TLO.New.getNode());
Scott Michelfdc40a02009-02-17 22:15:04 +0000611
Chris Lattnerf8dc0612008-02-03 06:49:24 +0000612 // Finally, if the node is now dead, remove it from the graph. The node
613 // may not be dead if the replacement process recursively simplified to
614 // something else needing this node.
Gabor Greifba36cb52008-08-28 21:40:38 +0000615 if (TLO.Old.getNode()->use_empty()) {
616 removeFromWorkList(TLO.Old.getNode());
Scott Michelfdc40a02009-02-17 22:15:04 +0000617
Chris Lattnerf8dc0612008-02-03 06:49:24 +0000618 // If the operands of this node are only used by the node, they will now
619 // be dead. Make sure to visit them first to delete dead nodes early.
Gabor Greifba36cb52008-08-28 21:40:38 +0000620 for (unsigned i = 0, e = TLO.Old.getNode()->getNumOperands(); i != e; ++i)
621 if (TLO.Old.getNode()->getOperand(i).getNode()->hasOneUse())
622 AddToWorkList(TLO.Old.getNode()->getOperand(i).getNode());
Scott Michelfdc40a02009-02-17 22:15:04 +0000623
Gabor Greifba36cb52008-08-28 21:40:38 +0000624 DAG.DeleteNode(TLO.Old.getNode());
Chris Lattnerf8dc0612008-02-03 06:49:24 +0000625 }
Dan Gohmane5af2d32009-01-29 01:59:02 +0000626}
627
628/// SimplifyDemandedBits - Check the specified integer node value to see if
629/// it can be simplified or if things it uses can be simplified by bit
630/// propagation. If so, return true.
631bool DAGCombiner::SimplifyDemandedBits(SDValue Op, const APInt &Demanded) {
Evan Chenge5b51ac2010-04-17 06:13:15 +0000632 TargetLowering::TargetLoweringOpt TLO(DAG, LegalTypes, LegalOperations);
Dan Gohmane5af2d32009-01-29 01:59:02 +0000633 APInt KnownZero, KnownOne;
634 if (!TLI.SimplifyDemandedBits(Op, Demanded, KnownZero, KnownOne, TLO))
635 return false;
Scott Michelfdc40a02009-02-17 22:15:04 +0000636
Dan Gohmane5af2d32009-01-29 01:59:02 +0000637 // Revisit the node.
638 AddToWorkList(Op.getNode());
Scott Michelfdc40a02009-02-17 22:15:04 +0000639
Dan Gohmane5af2d32009-01-29 01:59:02 +0000640 // Replace the old value with the new one.
641 ++NodesCombined;
Wesley Peckbf17cfa2010-11-23 03:31:01 +0000642 DEBUG(dbgs() << "\nReplacing.2 ";
Chris Lattnerbbbfa992009-08-23 06:35:02 +0000643 TLO.Old.getNode()->dump(&DAG);
David Greenef1090292010-01-05 01:25:00 +0000644 dbgs() << "\nWith: ";
Chris Lattnerbbbfa992009-08-23 06:35:02 +0000645 TLO.New.getNode()->dump(&DAG);
David Greenef1090292010-01-05 01:25:00 +0000646 dbgs() << '\n');
Scott Michelfdc40a02009-02-17 22:15:04 +0000647
Dan Gohmane5af2d32009-01-29 01:59:02 +0000648 CommitTargetLoweringOpt(TLO);
Chris Lattnerf8dc0612008-02-03 06:49:24 +0000649 return true;
650}
651
Evan Cheng95c57ea2010-04-24 04:43:44 +0000652void DAGCombiner::ReplaceLoadWithPromotedLoad(SDNode *Load, SDNode *ExtLoad) {
653 DebugLoc dl = Load->getDebugLoc();
654 EVT VT = Load->getValueType(0);
655 SDValue Trunc = DAG.getNode(ISD::TRUNCATE, dl, VT, SDValue(ExtLoad, 0));
Evan Cheng4c26e932010-04-19 19:29:22 +0000656
Evan Cheng95c57ea2010-04-24 04:43:44 +0000657 DEBUG(dbgs() << "\nReplacing.9 ";
658 Load->dump(&DAG);
659 dbgs() << "\nWith: ";
660 Trunc.getNode()->dump(&DAG);
661 dbgs() << '\n');
662 WorkListRemover DeadNodes(*this);
663 DAG.ReplaceAllUsesOfValueWith(SDValue(Load, 0), Trunc, &DeadNodes);
664 DAG.ReplaceAllUsesOfValueWith(SDValue(Load, 1), SDValue(ExtLoad, 1),
665 &DeadNodes);
666 removeFromWorkList(Load);
667 DAG.DeleteNode(Load);
Evan Chengac7eae52010-04-27 19:48:13 +0000668 AddToWorkList(Trunc.getNode());
Evan Cheng95c57ea2010-04-24 04:43:44 +0000669}
670
671SDValue DAGCombiner::PromoteOperand(SDValue Op, EVT PVT, bool &Replace) {
672 Replace = false;
Evan Cheng4c26e932010-04-19 19:29:22 +0000673 DebugLoc dl = Op.getDebugLoc();
Evan Chenge5b51ac2010-04-17 06:13:15 +0000674 if (LoadSDNode *LD = dyn_cast<LoadSDNode>(Op)) {
Evan Chengac7eae52010-04-27 19:48:13 +0000675 EVT MemVT = LD->getMemoryVT();
676 ISD::LoadExtType ExtType = ISD::isNON_EXTLoad(LD)
Owen Anderson95771af2011-02-25 21:41:48 +0000677 ? (TLI.isLoadExtLegal(ISD::ZEXTLOAD, MemVT) ? ISD::ZEXTLOAD
Eric Christopher503a64d2010-12-09 04:48:06 +0000678 : ISD::EXTLOAD)
Evan Chengac7eae52010-04-27 19:48:13 +0000679 : LD->getExtensionType();
Evan Cheng95c57ea2010-04-24 04:43:44 +0000680 Replace = true;
Stuart Hastingsa9011292011-02-16 16:23:55 +0000681 return DAG.getExtLoad(ExtType, dl, PVT,
Evan Chenge5b51ac2010-04-17 06:13:15 +0000682 LD->getChain(), LD->getBasePtr(),
Chris Lattner3d6ccfb2010-09-21 17:04:51 +0000683 LD->getPointerInfo(),
Evan Chengac7eae52010-04-27 19:48:13 +0000684 MemVT, LD->isVolatile(),
Evan Chenge5b51ac2010-04-17 06:13:15 +0000685 LD->isNonTemporal(), LD->getAlignment());
686 }
687
Evan Cheng4c26e932010-04-19 19:29:22 +0000688 unsigned Opc = Op.getOpcode();
Evan Chengcaf77402010-04-23 19:10:30 +0000689 switch (Opc) {
690 default: break;
691 case ISD::AssertSext:
Evan Cheng4c26e932010-04-19 19:29:22 +0000692 return DAG.getNode(ISD::AssertSext, dl, PVT,
Evan Cheng95c57ea2010-04-24 04:43:44 +0000693 SExtPromoteOperand(Op.getOperand(0), PVT),
Evan Cheng4c26e932010-04-19 19:29:22 +0000694 Op.getOperand(1));
Evan Chengcaf77402010-04-23 19:10:30 +0000695 case ISD::AssertZext:
Evan Cheng4c26e932010-04-19 19:29:22 +0000696 return DAG.getNode(ISD::AssertZext, dl, PVT,
Evan Cheng95c57ea2010-04-24 04:43:44 +0000697 ZExtPromoteOperand(Op.getOperand(0), PVT),
Evan Cheng4c26e932010-04-19 19:29:22 +0000698 Op.getOperand(1));
Evan Chengcaf77402010-04-23 19:10:30 +0000699 case ISD::Constant: {
700 unsigned ExtOpc =
Evan Cheng4c26e932010-04-19 19:29:22 +0000701 Op.getValueType().isByteSized() ? ISD::SIGN_EXTEND : ISD::ZERO_EXTEND;
Evan Chengcaf77402010-04-23 19:10:30 +0000702 return DAG.getNode(ExtOpc, dl, PVT, Op);
Wesley Peckbf17cfa2010-11-23 03:31:01 +0000703 }
Evan Chengcaf77402010-04-23 19:10:30 +0000704 }
705
706 if (!TLI.isOperationLegal(ISD::ANY_EXTEND, PVT))
Evan Chenge5b51ac2010-04-17 06:13:15 +0000707 return SDValue();
Evan Chengcaf77402010-04-23 19:10:30 +0000708 return DAG.getNode(ISD::ANY_EXTEND, dl, PVT, Op);
Evan Cheng64b7bf72010-04-16 06:14:10 +0000709}
710
Evan Cheng95c57ea2010-04-24 04:43:44 +0000711SDValue DAGCombiner::SExtPromoteOperand(SDValue Op, EVT PVT) {
Evan Chenge5b51ac2010-04-17 06:13:15 +0000712 if (!TLI.isOperationLegal(ISD::SIGN_EXTEND_INREG, PVT))
713 return SDValue();
714 EVT OldVT = Op.getValueType();
715 DebugLoc dl = Op.getDebugLoc();
Evan Cheng95c57ea2010-04-24 04:43:44 +0000716 bool Replace = false;
717 SDValue NewOp = PromoteOperand(Op, PVT, Replace);
718 if (NewOp.getNode() == 0)
Evan Chenge5b51ac2010-04-17 06:13:15 +0000719 return SDValue();
Evan Chengac7eae52010-04-27 19:48:13 +0000720 AddToWorkList(NewOp.getNode());
Evan Cheng95c57ea2010-04-24 04:43:44 +0000721
722 if (Replace)
723 ReplaceLoadWithPromotedLoad(Op.getNode(), NewOp.getNode());
724 return DAG.getNode(ISD::SIGN_EXTEND_INREG, dl, NewOp.getValueType(), NewOp,
Evan Chenge5b51ac2010-04-17 06:13:15 +0000725 DAG.getValueType(OldVT));
726}
727
Evan Cheng95c57ea2010-04-24 04:43:44 +0000728SDValue DAGCombiner::ZExtPromoteOperand(SDValue Op, EVT PVT) {
Evan Chenge5b51ac2010-04-17 06:13:15 +0000729 EVT OldVT = Op.getValueType();
730 DebugLoc dl = Op.getDebugLoc();
Evan Cheng95c57ea2010-04-24 04:43:44 +0000731 bool Replace = false;
732 SDValue NewOp = PromoteOperand(Op, PVT, Replace);
733 if (NewOp.getNode() == 0)
Evan Chenge5b51ac2010-04-17 06:13:15 +0000734 return SDValue();
Evan Chengac7eae52010-04-27 19:48:13 +0000735 AddToWorkList(NewOp.getNode());
Evan Cheng95c57ea2010-04-24 04:43:44 +0000736
737 if (Replace)
738 ReplaceLoadWithPromotedLoad(Op.getNode(), NewOp.getNode());
739 return DAG.getZeroExtendInReg(NewOp, dl, OldVT);
Evan Chenge5b51ac2010-04-17 06:13:15 +0000740}
741
Evan Cheng64b7bf72010-04-16 06:14:10 +0000742/// PromoteIntBinOp - Promote the specified integer binary operation if the
743/// target indicates it is beneficial. e.g. On x86, it's usually better to
744/// promote i16 operations to i32 since i16 instructions are longer.
745SDValue DAGCombiner::PromoteIntBinOp(SDValue Op) {
746 if (!LegalOperations)
747 return SDValue();
748
749 EVT VT = Op.getValueType();
750 if (VT.isVector() || !VT.isInteger())
751 return SDValue();
752
Evan Chenge5b51ac2010-04-17 06:13:15 +0000753 // If operation type is 'undesirable', e.g. i16 on x86, consider
754 // promoting it.
755 unsigned Opc = Op.getOpcode();
756 if (TLI.isTypeDesirableForOp(Opc, VT))
757 return SDValue();
758
Evan Cheng64b7bf72010-04-16 06:14:10 +0000759 EVT PVT = VT;
Evan Chenge5b51ac2010-04-17 06:13:15 +0000760 // Consult target whether it is a good idea to promote this operation and
761 // what's the right type to promote it to.
762 if (TLI.IsDesirableToPromoteOp(Op, PVT)) {
Evan Cheng64b7bf72010-04-16 06:14:10 +0000763 assert(PVT != VT && "Don't know what type to promote to!");
764
Evan Cheng95c57ea2010-04-24 04:43:44 +0000765 bool Replace0 = false;
766 SDValue N0 = Op.getOperand(0);
767 SDValue NN0 = PromoteOperand(N0, PVT, Replace0);
768 if (NN0.getNode() == 0)
Evan Cheng07c4e102010-04-22 20:19:46 +0000769 return SDValue();
770
Evan Cheng95c57ea2010-04-24 04:43:44 +0000771 bool Replace1 = false;
772 SDValue N1 = Op.getOperand(1);
Evan Chengaad753b2010-05-10 19:03:57 +0000773 SDValue NN1;
774 if (N0 == N1)
775 NN1 = NN0;
776 else {
777 NN1 = PromoteOperand(N1, PVT, Replace1);
778 if (NN1.getNode() == 0)
779 return SDValue();
780 }
Evan Cheng07c4e102010-04-22 20:19:46 +0000781
Evan Cheng95c57ea2010-04-24 04:43:44 +0000782 AddToWorkList(NN0.getNode());
Evan Chengaad753b2010-05-10 19:03:57 +0000783 if (NN1.getNode())
784 AddToWorkList(NN1.getNode());
Evan Cheng95c57ea2010-04-24 04:43:44 +0000785
786 if (Replace0)
787 ReplaceLoadWithPromotedLoad(N0.getNode(), NN0.getNode());
788 if (Replace1)
789 ReplaceLoadWithPromotedLoad(N1.getNode(), NN1.getNode());
Evan Cheng07c4e102010-04-22 20:19:46 +0000790
Evan Chengac7eae52010-04-27 19:48:13 +0000791 DEBUG(dbgs() << "\nPromoting ";
792 Op.getNode()->dump(&DAG));
Evan Cheng07c4e102010-04-22 20:19:46 +0000793 DebugLoc dl = Op.getDebugLoc();
794 return DAG.getNode(ISD::TRUNCATE, dl, VT,
Evan Cheng95c57ea2010-04-24 04:43:44 +0000795 DAG.getNode(Opc, dl, PVT, NN0, NN1));
Evan Cheng07c4e102010-04-22 20:19:46 +0000796 }
797 return SDValue();
798}
799
800/// PromoteIntShiftOp - Promote the specified integer shift operation if the
801/// target indicates it is beneficial. e.g. On x86, it's usually better to
802/// promote i16 operations to i32 since i16 instructions are longer.
803SDValue DAGCombiner::PromoteIntShiftOp(SDValue Op) {
804 if (!LegalOperations)
805 return SDValue();
806
807 EVT VT = Op.getValueType();
808 if (VT.isVector() || !VT.isInteger())
809 return SDValue();
810
811 // If operation type is 'undesirable', e.g. i16 on x86, consider
812 // promoting it.
813 unsigned Opc = Op.getOpcode();
814 if (TLI.isTypeDesirableForOp(Opc, VT))
815 return SDValue();
816
817 EVT PVT = VT;
818 // Consult target whether it is a good idea to promote this operation and
819 // what's the right type to promote it to.
820 if (TLI.IsDesirableToPromoteOp(Op, PVT)) {
821 assert(PVT != VT && "Don't know what type to promote to!");
822
Evan Cheng95c57ea2010-04-24 04:43:44 +0000823 bool Replace = false;
Evan Chenge5b51ac2010-04-17 06:13:15 +0000824 SDValue N0 = Op.getOperand(0);
825 if (Opc == ISD::SRA)
Evan Cheng95c57ea2010-04-24 04:43:44 +0000826 N0 = SExtPromoteOperand(Op.getOperand(0), PVT);
Evan Chenge5b51ac2010-04-17 06:13:15 +0000827 else if (Opc == ISD::SRL)
Evan Cheng95c57ea2010-04-24 04:43:44 +0000828 N0 = ZExtPromoteOperand(Op.getOperand(0), PVT);
Evan Chenge5b51ac2010-04-17 06:13:15 +0000829 else
Evan Cheng95c57ea2010-04-24 04:43:44 +0000830 N0 = PromoteOperand(N0, PVT, Replace);
Evan Chenge5b51ac2010-04-17 06:13:15 +0000831 if (N0.getNode() == 0)
832 return SDValue();
Evan Cheng95c57ea2010-04-24 04:43:44 +0000833
Evan Chenge5b51ac2010-04-17 06:13:15 +0000834 AddToWorkList(N0.getNode());
Evan Cheng95c57ea2010-04-24 04:43:44 +0000835 if (Replace)
836 ReplaceLoadWithPromotedLoad(Op.getOperand(0).getNode(), N0.getNode());
Evan Cheng64b7bf72010-04-16 06:14:10 +0000837
Evan Chengac7eae52010-04-27 19:48:13 +0000838 DEBUG(dbgs() << "\nPromoting ";
839 Op.getNode()->dump(&DAG));
Evan Cheng64b7bf72010-04-16 06:14:10 +0000840 DebugLoc dl = Op.getDebugLoc();
841 return DAG.getNode(ISD::TRUNCATE, dl, VT,
Evan Cheng07c4e102010-04-22 20:19:46 +0000842 DAG.getNode(Opc, dl, PVT, N0, Op.getOperand(1)));
Evan Cheng64b7bf72010-04-16 06:14:10 +0000843 }
844 return SDValue();
845}
846
Evan Cheng4c26e932010-04-19 19:29:22 +0000847SDValue DAGCombiner::PromoteExtend(SDValue Op) {
848 if (!LegalOperations)
849 return SDValue();
850
851 EVT VT = Op.getValueType();
852 if (VT.isVector() || !VT.isInteger())
853 return SDValue();
854
855 // If operation type is 'undesirable', e.g. i16 on x86, consider
856 // promoting it.
857 unsigned Opc = Op.getOpcode();
858 if (TLI.isTypeDesirableForOp(Opc, VT))
859 return SDValue();
860
861 EVT PVT = VT;
862 // Consult target whether it is a good idea to promote this operation and
863 // what's the right type to promote it to.
864 if (TLI.IsDesirableToPromoteOp(Op, PVT)) {
865 assert(PVT != VT && "Don't know what type to promote to!");
866 // fold (aext (aext x)) -> (aext x)
867 // fold (aext (zext x)) -> (zext x)
868 // fold (aext (sext x)) -> (sext x)
Evan Chengac7eae52010-04-27 19:48:13 +0000869 DEBUG(dbgs() << "\nPromoting ";
870 Op.getNode()->dump(&DAG));
Evan Cheng4c26e932010-04-19 19:29:22 +0000871 return DAG.getNode(Op.getOpcode(), Op.getDebugLoc(), VT, Op.getOperand(0));
872 }
873 return SDValue();
874}
875
876bool DAGCombiner::PromoteLoad(SDValue Op) {
877 if (!LegalOperations)
878 return false;
879
880 EVT VT = Op.getValueType();
881 if (VT.isVector() || !VT.isInteger())
882 return false;
883
884 // If operation type is 'undesirable', e.g. i16 on x86, consider
885 // promoting it.
886 unsigned Opc = Op.getOpcode();
887 if (TLI.isTypeDesirableForOp(Opc, VT))
888 return false;
889
890 EVT PVT = VT;
891 // Consult target whether it is a good idea to promote this operation and
892 // what's the right type to promote it to.
893 if (TLI.IsDesirableToPromoteOp(Op, PVT)) {
894 assert(PVT != VT && "Don't know what type to promote to!");
895
896 DebugLoc dl = Op.getDebugLoc();
897 SDNode *N = Op.getNode();
898 LoadSDNode *LD = cast<LoadSDNode>(N);
Evan Chengac7eae52010-04-27 19:48:13 +0000899 EVT MemVT = LD->getMemoryVT();
900 ISD::LoadExtType ExtType = ISD::isNON_EXTLoad(LD)
Owen Anderson95771af2011-02-25 21:41:48 +0000901 ? (TLI.isLoadExtLegal(ISD::ZEXTLOAD, MemVT) ? ISD::ZEXTLOAD
Eric Christopher503a64d2010-12-09 04:48:06 +0000902 : ISD::EXTLOAD)
Evan Chengac7eae52010-04-27 19:48:13 +0000903 : LD->getExtensionType();
Stuart Hastingsa9011292011-02-16 16:23:55 +0000904 SDValue NewLD = DAG.getExtLoad(ExtType, dl, PVT,
Evan Cheng4c26e932010-04-19 19:29:22 +0000905 LD->getChain(), LD->getBasePtr(),
Chris Lattner3d6ccfb2010-09-21 17:04:51 +0000906 LD->getPointerInfo(),
Evan Chengac7eae52010-04-27 19:48:13 +0000907 MemVT, LD->isVolatile(),
Evan Cheng4c26e932010-04-19 19:29:22 +0000908 LD->isNonTemporal(), LD->getAlignment());
909 SDValue Result = DAG.getNode(ISD::TRUNCATE, dl, VT, NewLD);
910
Evan Cheng95c57ea2010-04-24 04:43:44 +0000911 DEBUG(dbgs() << "\nPromoting ";
Evan Cheng4c26e932010-04-19 19:29:22 +0000912 N->dump(&DAG);
Evan Cheng95c57ea2010-04-24 04:43:44 +0000913 dbgs() << "\nTo: ";
Evan Cheng4c26e932010-04-19 19:29:22 +0000914 Result.getNode()->dump(&DAG);
915 dbgs() << '\n');
916 WorkListRemover DeadNodes(*this);
917 DAG.ReplaceAllUsesOfValueWith(SDValue(N, 0), Result, &DeadNodes);
918 DAG.ReplaceAllUsesOfValueWith(SDValue(N, 1), NewLD.getValue(1), &DeadNodes);
919 removeFromWorkList(N);
920 DAG.DeleteNode(N);
Evan Chengac7eae52010-04-27 19:48:13 +0000921 AddToWorkList(Result.getNode());
Evan Cheng4c26e932010-04-19 19:29:22 +0000922 return true;
923 }
924 return false;
925}
926
Evan Chenge5b51ac2010-04-17 06:13:15 +0000927
Chris Lattner29446522007-05-14 22:04:50 +0000928//===----------------------------------------------------------------------===//
929// Main DAG Combiner implementation
930//===----------------------------------------------------------------------===//
931
Duncan Sands25cf2272008-11-24 14:53:14 +0000932void DAGCombiner::Run(CombineLevel AtLevel) {
933 // set the instance variables, so that the various visit routines may use it.
934 Level = AtLevel;
935 LegalOperations = Level >= NoIllegalOperations;
936 LegalTypes = Level >= NoIllegalTypes;
Nate Begeman4ebd8052005-09-01 23:24:04 +0000937
Evan Cheng17a568b2008-08-29 22:21:44 +0000938 // Add all the dag nodes to the worklist.
939 WorkList.reserve(DAG.allnodes_size());
940 for (SelectionDAG::allnodes_iterator I = DAG.allnodes_begin(),
941 E = DAG.allnodes_end(); I != E; ++I)
942 WorkList.push_back(I);
Duncan Sands25cf2272008-11-24 14:53:14 +0000943
Evan Cheng17a568b2008-08-29 22:21:44 +0000944 // Create a dummy node (which is not added to allnodes), that adds a reference
945 // to the root node, preventing it from being deleted, and tracking any
946 // changes of the root.
947 HandleSDNode Dummy(DAG.getRoot());
Scott Michelfdc40a02009-02-17 22:15:04 +0000948
Jim Laskey26f7fa72006-10-17 19:33:52 +0000949 // The root of the dag may dangle to deleted nodes until the dag combiner is
950 // done. Set it to null to avoid confusion.
Dan Gohman475871a2008-07-27 21:46:04 +0000951 DAG.setRoot(SDValue());
Scott Michelfdc40a02009-02-17 22:15:04 +0000952
Evan Cheng17a568b2008-08-29 22:21:44 +0000953 // while the worklist isn't empty, inspect the node on the end of it and
954 // try and combine it.
955 while (!WorkList.empty()) {
956 SDNode *N = WorkList.back();
957 WorkList.pop_back();
Scott Michelfdc40a02009-02-17 22:15:04 +0000958
Evan Cheng17a568b2008-08-29 22:21:44 +0000959 // If N has no uses, it is dead. Make sure to revisit all N's operands once
960 // N is deleted from the DAG, since they too may now be dead or may have a
961 // reduced number of uses, allowing other xforms.
962 if (N->use_empty() && N != &Dummy) {
963 for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i)
964 AddToWorkList(N->getOperand(i).getNode());
Scott Michelfdc40a02009-02-17 22:15:04 +0000965
Evan Cheng17a568b2008-08-29 22:21:44 +0000966 DAG.DeleteNode(N);
967 continue;
Nate Begeman1d4d4142005-09-01 00:19:25 +0000968 }
Scott Michelfdc40a02009-02-17 22:15:04 +0000969
Evan Cheng17a568b2008-08-29 22:21:44 +0000970 SDValue RV = combine(N);
Scott Michelfdc40a02009-02-17 22:15:04 +0000971
Evan Cheng17a568b2008-08-29 22:21:44 +0000972 if (RV.getNode() == 0)
973 continue;
Scott Michelfdc40a02009-02-17 22:15:04 +0000974
Evan Cheng17a568b2008-08-29 22:21:44 +0000975 ++NodesCombined;
Scott Michelfdc40a02009-02-17 22:15:04 +0000976
Evan Cheng17a568b2008-08-29 22:21:44 +0000977 // If we get back the same node we passed in, rather than a new node or
978 // zero, we know that the node must have defined multiple values and
Scott Michelfdc40a02009-02-17 22:15:04 +0000979 // CombineTo was used. Since CombineTo takes care of the worklist
Evan Cheng17a568b2008-08-29 22:21:44 +0000980 // mechanics for us, we have no work to do in this case.
981 if (RV.getNode() == N)
982 continue;
Scott Michelfdc40a02009-02-17 22:15:04 +0000983
Evan Cheng17a568b2008-08-29 22:21:44 +0000984 assert(N->getOpcode() != ISD::DELETED_NODE &&
985 RV.getNode()->getOpcode() != ISD::DELETED_NODE &&
986 "Node was deleted but visit returned new node!");
Chris Lattner729c6d12006-05-27 00:43:02 +0000987
Wesley Peckbf17cfa2010-11-23 03:31:01 +0000988 DEBUG(dbgs() << "\nReplacing.3 ";
Chris Lattnerbbbfa992009-08-23 06:35:02 +0000989 N->dump(&DAG);
David Greenef1090292010-01-05 01:25:00 +0000990 dbgs() << "\nWith: ";
Chris Lattnerbbbfa992009-08-23 06:35:02 +0000991 RV.getNode()->dump(&DAG);
David Greenef1090292010-01-05 01:25:00 +0000992 dbgs() << '\n');
Evan Cheng17a568b2008-08-29 22:21:44 +0000993 WorkListRemover DeadNodes(*this);
994 if (N->getNumValues() == RV.getNode()->getNumValues())
995 DAG.ReplaceAllUsesWith(N, RV.getNode(), &DeadNodes);
996 else {
997 assert(N->getValueType(0) == RV.getValueType() &&
998 N->getNumValues() == 1 && "Type mismatch");
999 SDValue OpV = RV;
1000 DAG.ReplaceAllUsesWith(N, &OpV, &DeadNodes);
1001 }
Scott Michelfdc40a02009-02-17 22:15:04 +00001002
Evan Cheng17a568b2008-08-29 22:21:44 +00001003 // Push the new node and any users onto the worklist
1004 AddToWorkList(RV.getNode());
1005 AddUsersToWorkList(RV.getNode());
Scott Michelfdc40a02009-02-17 22:15:04 +00001006
Evan Cheng17a568b2008-08-29 22:21:44 +00001007 // Add any uses of the old node to the worklist in case this node is the
1008 // last one that uses them. They may become dead after this node is
1009 // deleted.
1010 for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i)
1011 AddToWorkList(N->getOperand(i).getNode());
Scott Michelfdc40a02009-02-17 22:15:04 +00001012
Dan Gohmandbe664a2009-01-19 21:44:21 +00001013 // Finally, if the node is now dead, remove it from the graph. The node
1014 // may not be dead if the replacement process recursively simplified to
1015 // something else needing this node.
1016 if (N->use_empty()) {
1017 // Nodes can be reintroduced into the worklist. Make sure we do not
1018 // process a node that has been replaced.
1019 removeFromWorkList(N);
Scott Michelfdc40a02009-02-17 22:15:04 +00001020
Dan Gohmandbe664a2009-01-19 21:44:21 +00001021 // Finally, since the node is now dead, remove it from the graph.
1022 DAG.DeleteNode(N);
1023 }
Evan Cheng17a568b2008-08-29 22:21:44 +00001024 }
Scott Michelfdc40a02009-02-17 22:15:04 +00001025
Chris Lattner95038592005-10-05 06:35:28 +00001026 // If the root changed (e.g. it was a dead load, update the root).
1027 DAG.setRoot(Dummy.getValue());
Nate Begeman1d4d4142005-09-01 00:19:25 +00001028}
1029
Dan Gohman475871a2008-07-27 21:46:04 +00001030SDValue DAGCombiner::visit(SDNode *N) {
Evan Chengb3a3d5e2010-04-28 07:10:39 +00001031 switch (N->getOpcode()) {
Nate Begeman1d4d4142005-09-01 00:19:25 +00001032 default: break;
Nate Begeman4942a962005-09-01 00:33:32 +00001033 case ISD::TokenFactor: return visitTokenFactor(N);
Chris Lattnerfec42eb2008-02-13 07:25:05 +00001034 case ISD::MERGE_VALUES: return visitMERGE_VALUES(N);
Nate Begeman646d7e22005-09-02 21:18:40 +00001035 case ISD::ADD: return visitADD(N);
1036 case ISD::SUB: return visitSUB(N);
Chris Lattner91153682007-03-04 20:03:15 +00001037 case ISD::ADDC: return visitADDC(N);
1038 case ISD::ADDE: return visitADDE(N);
Nate Begeman646d7e22005-09-02 21:18:40 +00001039 case ISD::MUL: return visitMUL(N);
1040 case ISD::SDIV: return visitSDIV(N);
1041 case ISD::UDIV: return visitUDIV(N);
1042 case ISD::SREM: return visitSREM(N);
1043 case ISD::UREM: return visitUREM(N);
1044 case ISD::MULHU: return visitMULHU(N);
1045 case ISD::MULHS: return visitMULHS(N);
Dan Gohman389079b2007-10-08 17:57:15 +00001046 case ISD::SMUL_LOHI: return visitSMUL_LOHI(N);
1047 case ISD::UMUL_LOHI: return visitUMUL_LOHI(N);
1048 case ISD::SDIVREM: return visitSDIVREM(N);
1049 case ISD::UDIVREM: return visitUDIVREM(N);
Nate Begeman646d7e22005-09-02 21:18:40 +00001050 case ISD::AND: return visitAND(N);
1051 case ISD::OR: return visitOR(N);
1052 case ISD::XOR: return visitXOR(N);
1053 case ISD::SHL: return visitSHL(N);
1054 case ISD::SRA: return visitSRA(N);
1055 case ISD::SRL: return visitSRL(N);
1056 case ISD::CTLZ: return visitCTLZ(N);
1057 case ISD::CTTZ: return visitCTTZ(N);
1058 case ISD::CTPOP: return visitCTPOP(N);
Nate Begeman452d7beb2005-09-16 00:54:12 +00001059 case ISD::SELECT: return visitSELECT(N);
1060 case ISD::SELECT_CC: return visitSELECT_CC(N);
1061 case ISD::SETCC: return visitSETCC(N);
Nate Begeman646d7e22005-09-02 21:18:40 +00001062 case ISD::SIGN_EXTEND: return visitSIGN_EXTEND(N);
1063 case ISD::ZERO_EXTEND: return visitZERO_EXTEND(N);
Chris Lattner5ffc0662006-05-05 05:58:59 +00001064 case ISD::ANY_EXTEND: return visitANY_EXTEND(N);
Nate Begeman646d7e22005-09-02 21:18:40 +00001065 case ISD::SIGN_EXTEND_INREG: return visitSIGN_EXTEND_INREG(N);
1066 case ISD::TRUNCATE: return visitTRUNCATE(N);
Wesley Peckbf17cfa2010-11-23 03:31:01 +00001067 case ISD::BITCAST: return visitBITCAST(N);
Evan Cheng9bfa03c2008-05-12 23:04:07 +00001068 case ISD::BUILD_PAIR: return visitBUILD_PAIR(N);
Chris Lattner01b3d732005-09-28 22:28:18 +00001069 case ISD::FADD: return visitFADD(N);
1070 case ISD::FSUB: return visitFSUB(N);
1071 case ISD::FMUL: return visitFMUL(N);
1072 case ISD::FDIV: return visitFDIV(N);
1073 case ISD::FREM: return visitFREM(N);
Chris Lattner12d83032006-03-05 05:30:57 +00001074 case ISD::FCOPYSIGN: return visitFCOPYSIGN(N);
Nate Begeman646d7e22005-09-02 21:18:40 +00001075 case ISD::SINT_TO_FP: return visitSINT_TO_FP(N);
1076 case ISD::UINT_TO_FP: return visitUINT_TO_FP(N);
1077 case ISD::FP_TO_SINT: return visitFP_TO_SINT(N);
1078 case ISD::FP_TO_UINT: return visitFP_TO_UINT(N);
1079 case ISD::FP_ROUND: return visitFP_ROUND(N);
1080 case ISD::FP_ROUND_INREG: return visitFP_ROUND_INREG(N);
1081 case ISD::FP_EXTEND: return visitFP_EXTEND(N);
1082 case ISD::FNEG: return visitFNEG(N);
1083 case ISD::FABS: return visitFABS(N);
Nate Begeman44728a72005-09-19 22:34:01 +00001084 case ISD::BRCOND: return visitBRCOND(N);
Nate Begeman44728a72005-09-19 22:34:01 +00001085 case ISD::BR_CC: return visitBR_CC(N);
Chris Lattner01a22022005-10-10 22:04:48 +00001086 case ISD::LOAD: return visitLOAD(N);
Chris Lattner87514ca2005-10-10 22:31:19 +00001087 case ISD::STORE: return visitSTORE(N);
Chris Lattnerca242442006-03-19 01:27:56 +00001088 case ISD::INSERT_VECTOR_ELT: return visitINSERT_VECTOR_ELT(N);
Evan Cheng513da432007-10-06 08:19:55 +00001089 case ISD::EXTRACT_VECTOR_ELT: return visitEXTRACT_VECTOR_ELT(N);
Dan Gohman7f321562007-06-25 16:23:39 +00001090 case ISD::BUILD_VECTOR: return visitBUILD_VECTOR(N);
1091 case ISD::CONCAT_VECTORS: return visitCONCAT_VECTORS(N);
Chris Lattner66445d32006-03-28 22:11:53 +00001092 case ISD::VECTOR_SHUFFLE: return visitVECTOR_SHUFFLE(N);
Jim Grosbach9a526492010-06-23 16:07:42 +00001093 case ISD::MEMBARRIER: return visitMEMBARRIER(N);
Nate Begeman1d4d4142005-09-01 00:19:25 +00001094 }
Dan Gohman475871a2008-07-27 21:46:04 +00001095 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00001096}
1097
Dan Gohman475871a2008-07-27 21:46:04 +00001098SDValue DAGCombiner::combine(SDNode *N) {
Dan Gohman475871a2008-07-27 21:46:04 +00001099 SDValue RV = visit(N);
Dan Gohman389079b2007-10-08 17:57:15 +00001100
1101 // If nothing happened, try a target-specific DAG combine.
Gabor Greifba36cb52008-08-28 21:40:38 +00001102 if (RV.getNode() == 0) {
Dan Gohman389079b2007-10-08 17:57:15 +00001103 assert(N->getOpcode() != ISD::DELETED_NODE &&
1104 "Node was deleted but visit returned NULL!");
1105
1106 if (N->getOpcode() >= ISD::BUILTIN_OP_END ||
1107 TLI.hasTargetDAGCombine((ISD::NodeType)N->getOpcode())) {
1108
1109 // Expose the DAG combiner to the target combiner impls.
Scott Michelfdc40a02009-02-17 22:15:04 +00001110 TargetLowering::DAGCombinerInfo
Jakob Stoklund Olesen78d12642009-07-24 18:22:59 +00001111 DagCombineInfo(DAG, !LegalTypes, !LegalOperations, false, this);
Dan Gohman389079b2007-10-08 17:57:15 +00001112
1113 RV = TLI.PerformDAGCombine(N, DagCombineInfo);
1114 }
1115 }
1116
Evan Chengb3a3d5e2010-04-28 07:10:39 +00001117 // If nothing happened still, try promoting the operation.
1118 if (RV.getNode() == 0) {
1119 switch (N->getOpcode()) {
1120 default: break;
1121 case ISD::ADD:
1122 case ISD::SUB:
1123 case ISD::MUL:
1124 case ISD::AND:
1125 case ISD::OR:
1126 case ISD::XOR:
1127 RV = PromoteIntBinOp(SDValue(N, 0));
1128 break;
1129 case ISD::SHL:
1130 case ISD::SRA:
1131 case ISD::SRL:
1132 RV = PromoteIntShiftOp(SDValue(N, 0));
1133 break;
1134 case ISD::SIGN_EXTEND:
1135 case ISD::ZERO_EXTEND:
1136 case ISD::ANY_EXTEND:
1137 RV = PromoteExtend(SDValue(N, 0));
1138 break;
1139 case ISD::LOAD:
1140 if (PromoteLoad(SDValue(N, 0)))
1141 RV = SDValue(N, 0);
1142 break;
1143 }
1144 }
1145
Scott Michelfdc40a02009-02-17 22:15:04 +00001146 // If N is a commutative binary node, try commuting it to enable more
Evan Cheng08b11732008-03-22 01:55:50 +00001147 // sdisel CSE.
Scott Michelfdc40a02009-02-17 22:15:04 +00001148 if (RV.getNode() == 0 &&
Evan Cheng08b11732008-03-22 01:55:50 +00001149 SelectionDAG::isCommutativeBinOp(N->getOpcode()) &&
1150 N->getNumValues() == 1) {
Dan Gohman475871a2008-07-27 21:46:04 +00001151 SDValue N0 = N->getOperand(0);
1152 SDValue N1 = N->getOperand(1);
Bill Wendling5c71acf2009-01-30 01:13:16 +00001153
Evan Cheng08b11732008-03-22 01:55:50 +00001154 // Constant operands are canonicalized to RHS.
1155 if (isa<ConstantSDNode>(N0) || !isa<ConstantSDNode>(N1)) {
Dan Gohman475871a2008-07-27 21:46:04 +00001156 SDValue Ops[] = { N1, N0 };
Evan Cheng08b11732008-03-22 01:55:50 +00001157 SDNode *CSENode = DAG.getNodeIfExists(N->getOpcode(), N->getVTList(),
1158 Ops, 2);
Evan Chengea100462008-03-24 23:55:16 +00001159 if (CSENode)
Dan Gohman475871a2008-07-27 21:46:04 +00001160 return SDValue(CSENode, 0);
Evan Cheng08b11732008-03-22 01:55:50 +00001161 }
1162 }
1163
Dan Gohman389079b2007-10-08 17:57:15 +00001164 return RV;
Scott Michelfdc40a02009-02-17 22:15:04 +00001165}
Dan Gohman389079b2007-10-08 17:57:15 +00001166
Chris Lattner6270f682006-10-08 22:57:01 +00001167/// getInputChainForNode - Given a node, return its input chain if it has one,
1168/// otherwise return a null sd operand.
Dan Gohman475871a2008-07-27 21:46:04 +00001169static SDValue getInputChainForNode(SDNode *N) {
Chris Lattner6270f682006-10-08 22:57:01 +00001170 if (unsigned NumOps = N->getNumOperands()) {
Owen Anderson825b72b2009-08-11 20:47:22 +00001171 if (N->getOperand(0).getValueType() == MVT::Other)
Chris Lattner6270f682006-10-08 22:57:01 +00001172 return N->getOperand(0);
Owen Anderson825b72b2009-08-11 20:47:22 +00001173 else if (N->getOperand(NumOps-1).getValueType() == MVT::Other)
Chris Lattner6270f682006-10-08 22:57:01 +00001174 return N->getOperand(NumOps-1);
1175 for (unsigned i = 1; i < NumOps-1; ++i)
Owen Anderson825b72b2009-08-11 20:47:22 +00001176 if (N->getOperand(i).getValueType() == MVT::Other)
Chris Lattner6270f682006-10-08 22:57:01 +00001177 return N->getOperand(i);
1178 }
Bill Wendling5c71acf2009-01-30 01:13:16 +00001179 return SDValue();
Chris Lattner6270f682006-10-08 22:57:01 +00001180}
1181
Dan Gohman475871a2008-07-27 21:46:04 +00001182SDValue DAGCombiner::visitTokenFactor(SDNode *N) {
Chris Lattner6270f682006-10-08 22:57:01 +00001183 // If N has two operands, where one has an input chain equal to the other,
1184 // the 'other' chain is redundant.
1185 if (N->getNumOperands() == 2) {
Gabor Greifba36cb52008-08-28 21:40:38 +00001186 if (getInputChainForNode(N->getOperand(0).getNode()) == N->getOperand(1))
Chris Lattner6270f682006-10-08 22:57:01 +00001187 return N->getOperand(0);
Gabor Greifba36cb52008-08-28 21:40:38 +00001188 if (getInputChainForNode(N->getOperand(1).getNode()) == N->getOperand(0))
Chris Lattner6270f682006-10-08 22:57:01 +00001189 return N->getOperand(1);
1190 }
Scott Michelfdc40a02009-02-17 22:15:04 +00001191
Chris Lattnerc76d4412007-05-16 06:37:59 +00001192 SmallVector<SDNode *, 8> TFs; // List of token factors to visit.
Dan Gohman475871a2008-07-27 21:46:04 +00001193 SmallVector<SDValue, 8> Ops; // Ops for replacing token factor.
Scott Michelfdc40a02009-02-17 22:15:04 +00001194 SmallPtrSet<SDNode*, 16> SeenOps;
Chris Lattnerc76d4412007-05-16 06:37:59 +00001195 bool Changed = false; // If we should replace this token factor.
Scott Michelfdc40a02009-02-17 22:15:04 +00001196
Jim Laskey6ff23e52006-10-04 16:53:27 +00001197 // Start out with this token factor.
Jim Laskey279f0532006-09-25 16:29:54 +00001198 TFs.push_back(N);
Scott Michelfdc40a02009-02-17 22:15:04 +00001199
Jim Laskey71382342006-10-07 23:37:56 +00001200 // Iterate through token factors. The TFs grows when new token factors are
Jim Laskeybc588b82006-10-05 15:07:25 +00001201 // encountered.
1202 for (unsigned i = 0; i < TFs.size(); ++i) {
1203 SDNode *TF = TFs[i];
Scott Michelfdc40a02009-02-17 22:15:04 +00001204
Jim Laskey6ff23e52006-10-04 16:53:27 +00001205 // Check each of the operands.
1206 for (unsigned i = 0, ie = TF->getNumOperands(); i != ie; ++i) {
Dan Gohman475871a2008-07-27 21:46:04 +00001207 SDValue Op = TF->getOperand(i);
Scott Michelfdc40a02009-02-17 22:15:04 +00001208
Jim Laskey6ff23e52006-10-04 16:53:27 +00001209 switch (Op.getOpcode()) {
1210 case ISD::EntryToken:
Jim Laskeybc588b82006-10-05 15:07:25 +00001211 // Entry tokens don't need to be added to the list. They are
1212 // rededundant.
1213 Changed = true;
Jim Laskey6ff23e52006-10-04 16:53:27 +00001214 break;
Scott Michelfdc40a02009-02-17 22:15:04 +00001215
Jim Laskey6ff23e52006-10-04 16:53:27 +00001216 case ISD::TokenFactor:
Nate Begemanb6aef5c2009-09-15 00:18:30 +00001217 if (Op.hasOneUse() &&
Gabor Greifba36cb52008-08-28 21:40:38 +00001218 std::find(TFs.begin(), TFs.end(), Op.getNode()) == TFs.end()) {
Jim Laskey6ff23e52006-10-04 16:53:27 +00001219 // Queue up for processing.
Gabor Greifba36cb52008-08-28 21:40:38 +00001220 TFs.push_back(Op.getNode());
Jim Laskey6ff23e52006-10-04 16:53:27 +00001221 // Clean up in case the token factor is removed.
Gabor Greifba36cb52008-08-28 21:40:38 +00001222 AddToWorkList(Op.getNode());
Jim Laskey6ff23e52006-10-04 16:53:27 +00001223 Changed = true;
1224 break;
Jim Laskey279f0532006-09-25 16:29:54 +00001225 }
Jim Laskey6ff23e52006-10-04 16:53:27 +00001226 // Fall thru
Scott Michelfdc40a02009-02-17 22:15:04 +00001227
Jim Laskey6ff23e52006-10-04 16:53:27 +00001228 default:
Chris Lattnerc76d4412007-05-16 06:37:59 +00001229 // Only add if it isn't already in the list.
Gabor Greifba36cb52008-08-28 21:40:38 +00001230 if (SeenOps.insert(Op.getNode()))
Jim Laskeybc588b82006-10-05 15:07:25 +00001231 Ops.push_back(Op);
Chris Lattnerc76d4412007-05-16 06:37:59 +00001232 else
1233 Changed = true;
Jim Laskey6ff23e52006-10-04 16:53:27 +00001234 break;
Jim Laskey279f0532006-09-25 16:29:54 +00001235 }
1236 }
Jim Laskey6ff23e52006-10-04 16:53:27 +00001237 }
Wesley Peckbf17cfa2010-11-23 03:31:01 +00001238
Dan Gohman475871a2008-07-27 21:46:04 +00001239 SDValue Result;
Jim Laskey6ff23e52006-10-04 16:53:27 +00001240
1241 // If we've change things around then replace token factor.
1242 if (Changed) {
Dan Gohman30359592008-01-29 13:02:09 +00001243 if (Ops.empty()) {
Jim Laskey6ff23e52006-10-04 16:53:27 +00001244 // The entry token is the only possible outcome.
1245 Result = DAG.getEntryNode();
1246 } else {
1247 // New and improved token factor.
Bill Wendling5c71acf2009-01-30 01:13:16 +00001248 Result = DAG.getNode(ISD::TokenFactor, N->getDebugLoc(),
Owen Anderson825b72b2009-08-11 20:47:22 +00001249 MVT::Other, &Ops[0], Ops.size());
Nate Begemanded49632005-10-13 03:11:28 +00001250 }
Bill Wendling5c71acf2009-01-30 01:13:16 +00001251
Jim Laskey274062c2006-10-13 23:32:28 +00001252 // Don't add users to work list.
1253 return CombineTo(N, Result, false);
Nate Begemanded49632005-10-13 03:11:28 +00001254 }
Scott Michelfdc40a02009-02-17 22:15:04 +00001255
Jim Laskey6ff23e52006-10-04 16:53:27 +00001256 return Result;
Nate Begeman1d4d4142005-09-01 00:19:25 +00001257}
1258
Chris Lattnerfec42eb2008-02-13 07:25:05 +00001259/// MERGE_VALUES can always be eliminated.
Dan Gohman475871a2008-07-27 21:46:04 +00001260SDValue DAGCombiner::visitMERGE_VALUES(SDNode *N) {
Chris Lattnerfec42eb2008-02-13 07:25:05 +00001261 WorkListRemover DeadNodes(*this);
Dan Gohman00edf392009-08-10 23:43:19 +00001262 // Replacing results may cause a different MERGE_VALUES to suddenly
1263 // be CSE'd with N, and carry its uses with it. Iterate until no
1264 // uses remain, to ensure that the node can be safely deleted.
1265 do {
1266 for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i)
1267 DAG.ReplaceAllUsesOfValueWith(SDValue(N, i), N->getOperand(i),
1268 &DeadNodes);
1269 } while (!N->use_empty());
Chris Lattnerfec42eb2008-02-13 07:25:05 +00001270 removeFromWorkList(N);
1271 DAG.DeleteNode(N);
Dan Gohman475871a2008-07-27 21:46:04 +00001272 return SDValue(N, 0); // Return N so it doesn't get rechecked!
Chris Lattnerfec42eb2008-02-13 07:25:05 +00001273}
1274
Evan Cheng42d7ccf2007-01-19 17:51:44 +00001275static
Bill Wendlingd69c3142009-01-30 02:23:43 +00001276SDValue combineShlAddConstant(DebugLoc DL, SDValue N0, SDValue N1,
1277 SelectionDAG &DAG) {
Owen Andersone50ed302009-08-10 22:56:29 +00001278 EVT VT = N0.getValueType();
Dan Gohman475871a2008-07-27 21:46:04 +00001279 SDValue N00 = N0.getOperand(0);
1280 SDValue N01 = N0.getOperand(1);
Evan Cheng42d7ccf2007-01-19 17:51:44 +00001281 ConstantSDNode *N01C = dyn_cast<ConstantSDNode>(N01);
Bill Wendlingd69c3142009-01-30 02:23:43 +00001282
Gabor Greifba36cb52008-08-28 21:40:38 +00001283 if (N01C && N00.getOpcode() == ISD::ADD && N00.getNode()->hasOneUse() &&
Evan Cheng42d7ccf2007-01-19 17:51:44 +00001284 isa<ConstantSDNode>(N00.getOperand(1))) {
Bill Wendlingd69c3142009-01-30 02:23:43 +00001285 // fold (add (shl (add x, c1), c2), ) -> (add (add (shl x, c2), c1<<c2), )
1286 N0 = DAG.getNode(ISD::ADD, N0.getDebugLoc(), VT,
1287 DAG.getNode(ISD::SHL, N00.getDebugLoc(), VT,
1288 N00.getOperand(0), N01),
1289 DAG.getNode(ISD::SHL, N01.getDebugLoc(), VT,
1290 N00.getOperand(1), N01));
1291 return DAG.getNode(ISD::ADD, DL, VT, N0, N1);
Evan Cheng42d7ccf2007-01-19 17:51:44 +00001292 }
Bill Wendlingd69c3142009-01-30 02:23:43 +00001293
Dan Gohman475871a2008-07-27 21:46:04 +00001294 return SDValue();
Evan Cheng42d7ccf2007-01-19 17:51:44 +00001295}
1296
Benjamin Kramer74666782011-02-26 22:48:07 +00001297/// isCarryMaterialization - Returns true if V is an ADDE node that is known to
1298/// return 0 or 1 depending on the carry flag.
1299static bool isCarryMaterialization(SDValue V) {
1300 if (V.getOpcode() != ISD::ADDE)
1301 return false;
1302
1303 ConstantSDNode *C = dyn_cast<ConstantSDNode>(V.getOperand(0));
1304 return C && C->isNullValue() && V.getOperand(0) == V.getOperand(1);
1305}
1306
Dan Gohman475871a2008-07-27 21:46:04 +00001307SDValue DAGCombiner::visitADD(SDNode *N) {
1308 SDValue N0 = N->getOperand(0);
1309 SDValue N1 = N->getOperand(1);
Nate Begeman646d7e22005-09-02 21:18:40 +00001310 ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0);
1311 ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1);
Owen Andersone50ed302009-08-10 22:56:29 +00001312 EVT VT = N0.getValueType();
Dan Gohman7f321562007-06-25 16:23:39 +00001313
1314 // fold vector ops
Duncan Sands83ec4b62008-06-06 12:08:01 +00001315 if (VT.isVector()) {
Dan Gohman475871a2008-07-27 21:46:04 +00001316 SDValue FoldedVOp = SimplifyVBinOp(N);
Gabor Greifba36cb52008-08-28 21:40:38 +00001317 if (FoldedVOp.getNode()) return FoldedVOp;
Dan Gohman05d92fe2007-07-13 20:03:40 +00001318 }
Bill Wendling2476e5d2008-12-10 22:36:00 +00001319
Dan Gohman613e0d82007-07-03 14:03:57 +00001320 // fold (add x, undef) -> undef
Dan Gohman70fb1ae2007-07-10 15:19:29 +00001321 if (N0.getOpcode() == ISD::UNDEF)
1322 return N0;
1323 if (N1.getOpcode() == ISD::UNDEF)
Dan Gohman613e0d82007-07-03 14:03:57 +00001324 return N1;
Nate Begeman1d4d4142005-09-01 00:19:25 +00001325 // fold (add c1, c2) -> c1+c2
Nate Begeman646d7e22005-09-02 21:18:40 +00001326 if (N0C && N1C)
Bill Wendlingf3cbca22008-09-24 10:25:02 +00001327 return DAG.FoldConstantArithmetic(ISD::ADD, VT, N0C, N1C);
Nate Begeman99801192005-09-07 23:25:52 +00001328 // canonicalize constant to RHS
Nate Begemana0e221d2005-10-18 00:28:13 +00001329 if (N0C && !N1C)
Bill Wendlingf4eb2262009-01-30 02:31:17 +00001330 return DAG.getNode(ISD::ADD, N->getDebugLoc(), VT, N1, N0);
Nate Begeman1d4d4142005-09-01 00:19:25 +00001331 // fold (add x, 0) -> x
Nate Begeman646d7e22005-09-02 21:18:40 +00001332 if (N1C && N1C->isNullValue())
Nate Begeman83e75ec2005-09-06 04:43:02 +00001333 return N0;
Dan Gohman6520e202008-10-18 02:06:02 +00001334 // fold (add Sym, c) -> Sym+c
1335 if (GlobalAddressSDNode *GA = dyn_cast<GlobalAddressSDNode>(N0))
Duncan Sands25cf2272008-11-24 14:53:14 +00001336 if (!LegalOperations && TLI.isOffsetFoldingLegal(GA) && N1C &&
Dan Gohman6520e202008-10-18 02:06:02 +00001337 GA->getOpcode() == ISD::GlobalAddress)
Devang Patel0d881da2010-07-06 22:08:15 +00001338 return DAG.getGlobalAddress(GA->getGlobal(), N1C->getDebugLoc(), VT,
Dan Gohman6520e202008-10-18 02:06:02 +00001339 GA->getOffset() +
1340 (uint64_t)N1C->getSExtValue());
Chris Lattner4aafb4f2006-01-12 20:22:43 +00001341 // fold ((c1-A)+c2) -> (c1+c2)-A
1342 if (N1C && N0.getOpcode() == ISD::SUB)
1343 if (ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0.getOperand(0)))
Bill Wendlingf4eb2262009-01-30 02:31:17 +00001344 return DAG.getNode(ISD::SUB, N->getDebugLoc(), VT,
Dan Gohman002e5d02008-03-13 22:13:53 +00001345 DAG.getConstant(N1C->getAPIntValue()+
1346 N0C->getAPIntValue(), VT),
Chris Lattner4aafb4f2006-01-12 20:22:43 +00001347 N0.getOperand(1));
Nate Begemancd4d58c2006-02-03 06:46:56 +00001348 // reassociate add
Bill Wendling35247c32009-01-30 00:45:56 +00001349 SDValue RADD = ReassociateOps(ISD::ADD, N->getDebugLoc(), N0, N1);
Gabor Greifba36cb52008-08-28 21:40:38 +00001350 if (RADD.getNode() != 0)
Nate Begemancd4d58c2006-02-03 06:46:56 +00001351 return RADD;
Nate Begeman1d4d4142005-09-01 00:19:25 +00001352 // fold ((0-A) + B) -> B-A
1353 if (N0.getOpcode() == ISD::SUB && isa<ConstantSDNode>(N0.getOperand(0)) &&
1354 cast<ConstantSDNode>(N0.getOperand(0))->isNullValue())
Bill Wendlingf4eb2262009-01-30 02:31:17 +00001355 return DAG.getNode(ISD::SUB, N->getDebugLoc(), VT, N1, N0.getOperand(1));
Nate Begeman1d4d4142005-09-01 00:19:25 +00001356 // fold (A + (0-B)) -> A-B
1357 if (N1.getOpcode() == ISD::SUB && isa<ConstantSDNode>(N1.getOperand(0)) &&
1358 cast<ConstantSDNode>(N1.getOperand(0))->isNullValue())
Bill Wendlingf4eb2262009-01-30 02:31:17 +00001359 return DAG.getNode(ISD::SUB, N->getDebugLoc(), VT, N0, N1.getOperand(1));
Chris Lattner01b3d732005-09-28 22:28:18 +00001360 // fold (A+(B-A)) -> B
1361 if (N1.getOpcode() == ISD::SUB && N0 == N1.getOperand(1))
Nate Begeman83e75ec2005-09-06 04:43:02 +00001362 return N1.getOperand(0);
Dale Johannesen56eca912008-11-27 00:43:21 +00001363 // fold ((B-A)+A) -> B
1364 if (N0.getOpcode() == ISD::SUB && N1 == N0.getOperand(1))
1365 return N0.getOperand(0);
Dale Johannesen221cd2f2008-12-02 01:30:54 +00001366 // fold (A+(B-(A+C))) to (B-C)
1367 if (N1.getOpcode() == ISD::SUB && N1.getOperand(1).getOpcode() == ISD::ADD &&
Bill Wendlingf4eb2262009-01-30 02:31:17 +00001368 N0 == N1.getOperand(1).getOperand(0))
1369 return DAG.getNode(ISD::SUB, N->getDebugLoc(), VT, N1.getOperand(0),
Dale Johannesen221cd2f2008-12-02 01:30:54 +00001370 N1.getOperand(1).getOperand(1));
Dale Johannesen221cd2f2008-12-02 01:30:54 +00001371 // fold (A+(B-(C+A))) to (B-C)
1372 if (N1.getOpcode() == ISD::SUB && N1.getOperand(1).getOpcode() == ISD::ADD &&
Bill Wendlingf4eb2262009-01-30 02:31:17 +00001373 N0 == N1.getOperand(1).getOperand(1))
1374 return DAG.getNode(ISD::SUB, N->getDebugLoc(), VT, N1.getOperand(0),
Dale Johannesen221cd2f2008-12-02 01:30:54 +00001375 N1.getOperand(1).getOperand(0));
Dale Johannesen7c7bc722008-12-23 23:47:22 +00001376 // fold (A+((B-A)+or-C)) to (B+or-C)
Dale Johannesen34d79852008-12-02 18:40:40 +00001377 if ((N1.getOpcode() == ISD::SUB || N1.getOpcode() == ISD::ADD) &&
1378 N1.getOperand(0).getOpcode() == ISD::SUB &&
Bill Wendlingf4eb2262009-01-30 02:31:17 +00001379 N0 == N1.getOperand(0).getOperand(1))
1380 return DAG.getNode(N1.getOpcode(), N->getDebugLoc(), VT,
1381 N1.getOperand(0).getOperand(0), N1.getOperand(1));
Dale Johannesen34d79852008-12-02 18:40:40 +00001382
Dale Johannesen221cd2f2008-12-02 01:30:54 +00001383 // fold (A-B)+(C-D) to (A+C)-(B+D) when A or C is constant
1384 if (N0.getOpcode() == ISD::SUB && N1.getOpcode() == ISD::SUB) {
1385 SDValue N00 = N0.getOperand(0);
1386 SDValue N01 = N0.getOperand(1);
1387 SDValue N10 = N1.getOperand(0);
1388 SDValue N11 = N1.getOperand(1);
Bill Wendlingf4eb2262009-01-30 02:31:17 +00001389
1390 if (isa<ConstantSDNode>(N00) || isa<ConstantSDNode>(N10))
1391 return DAG.getNode(ISD::SUB, N->getDebugLoc(), VT,
1392 DAG.getNode(ISD::ADD, N0.getDebugLoc(), VT, N00, N10),
1393 DAG.getNode(ISD::ADD, N1.getDebugLoc(), VT, N01, N11));
Dale Johannesen221cd2f2008-12-02 01:30:54 +00001394 }
Chris Lattner947c2892006-03-13 06:51:27 +00001395
Dan Gohman475871a2008-07-27 21:46:04 +00001396 if (!VT.isVector() && SimplifyDemandedBits(SDValue(N, 0)))
1397 return SDValue(N, 0);
Scott Michelfdc40a02009-02-17 22:15:04 +00001398
Chris Lattner947c2892006-03-13 06:51:27 +00001399 // fold (a+b) -> (a|b) iff a and b share no bits.
Duncan Sands83ec4b62008-06-06 12:08:01 +00001400 if (VT.isInteger() && !VT.isVector()) {
Dan Gohman948d8ea2008-02-20 16:33:30 +00001401 APInt LHSZero, LHSOne;
1402 APInt RHSZero, RHSOne;
Dan Gohman5b870af2010-03-02 02:14:38 +00001403 APInt Mask = APInt::getAllOnesValue(VT.getScalarType().getSizeInBits());
Dan Gohmanea859be2007-06-22 14:59:07 +00001404 DAG.ComputeMaskedBits(N0, Mask, LHSZero, LHSOne);
Bill Wendlingf4eb2262009-01-30 02:31:17 +00001405
Dan Gohman948d8ea2008-02-20 16:33:30 +00001406 if (LHSZero.getBoolValue()) {
Dan Gohmanea859be2007-06-22 14:59:07 +00001407 DAG.ComputeMaskedBits(N1, Mask, RHSZero, RHSOne);
Scott Michelfdc40a02009-02-17 22:15:04 +00001408
Chris Lattner947c2892006-03-13 06:51:27 +00001409 // If all possibly-set bits on the LHS are clear on the RHS, return an OR.
1410 // If all possibly-set bits on the RHS are clear on the LHS, return an OR.
1411 if ((RHSZero & (~LHSZero & Mask)) == (~LHSZero & Mask) ||
1412 (LHSZero & (~RHSZero & Mask)) == (~RHSZero & Mask))
Bill Wendlingf4eb2262009-01-30 02:31:17 +00001413 return DAG.getNode(ISD::OR, N->getDebugLoc(), VT, N0, N1);
Chris Lattner947c2892006-03-13 06:51:27 +00001414 }
1415 }
Evan Cheng3ef554d2006-11-06 08:14:30 +00001416
Evan Cheng42d7ccf2007-01-19 17:51:44 +00001417 // fold (add (shl (add x, c1), c2), ) -> (add (add (shl x, c2), c1<<c2), )
Gabor Greifba36cb52008-08-28 21:40:38 +00001418 if (N0.getOpcode() == ISD::SHL && N0.getNode()->hasOneUse()) {
Bill Wendlingd69c3142009-01-30 02:23:43 +00001419 SDValue Result = combineShlAddConstant(N->getDebugLoc(), N0, N1, DAG);
Gabor Greifba36cb52008-08-28 21:40:38 +00001420 if (Result.getNode()) return Result;
Evan Cheng42d7ccf2007-01-19 17:51:44 +00001421 }
Gabor Greifba36cb52008-08-28 21:40:38 +00001422 if (N1.getOpcode() == ISD::SHL && N1.getNode()->hasOneUse()) {
Bill Wendlingd69c3142009-01-30 02:23:43 +00001423 SDValue Result = combineShlAddConstant(N->getDebugLoc(), N1, N0, DAG);
Gabor Greifba36cb52008-08-28 21:40:38 +00001424 if (Result.getNode()) return Result;
Evan Cheng42d7ccf2007-01-19 17:51:44 +00001425 }
1426
Dan Gohmancd9e1552010-01-19 23:30:49 +00001427 // fold (add x, shl(0 - y, n)) -> sub(x, shl(y, n))
1428 if (N1.getOpcode() == ISD::SHL &&
1429 N1.getOperand(0).getOpcode() == ISD::SUB)
1430 if (ConstantSDNode *C =
1431 dyn_cast<ConstantSDNode>(N1.getOperand(0).getOperand(0)))
1432 if (C->getAPIntValue() == 0)
1433 return DAG.getNode(ISD::SUB, N->getDebugLoc(), VT, N0,
1434 DAG.getNode(ISD::SHL, N->getDebugLoc(), VT,
1435 N1.getOperand(0).getOperand(1),
1436 N1.getOperand(1)));
1437 if (N0.getOpcode() == ISD::SHL &&
1438 N0.getOperand(0).getOpcode() == ISD::SUB)
1439 if (ConstantSDNode *C =
1440 dyn_cast<ConstantSDNode>(N0.getOperand(0).getOperand(0)))
1441 if (C->getAPIntValue() == 0)
1442 return DAG.getNode(ISD::SUB, N->getDebugLoc(), VT, N1,
1443 DAG.getNode(ISD::SHL, N->getDebugLoc(), VT,
1444 N0.getOperand(0).getOperand(1),
1445 N0.getOperand(1)));
1446
Owen Andersonbc146b02010-09-21 20:42:50 +00001447 if (N1.getOpcode() == ISD::AND) {
1448 SDValue AndOp0 = N1.getOperand(0);
Wesley Peckbf17cfa2010-11-23 03:31:01 +00001449 ConstantSDNode *AndOp1 = dyn_cast<ConstantSDNode>(N1->getOperand(1));
Owen Andersonbc146b02010-09-21 20:42:50 +00001450 unsigned NumSignBits = DAG.ComputeNumSignBits(AndOp0);
1451 unsigned DestBits = VT.getScalarType().getSizeInBits();
Wesley Peckbf17cfa2010-11-23 03:31:01 +00001452
Owen Andersonbc146b02010-09-21 20:42:50 +00001453 // (add z, (and (sbbl x, x), 1)) -> (sub z, (sbbl x, x))
1454 // and similar xforms where the inner op is either ~0 or 0.
1455 if (NumSignBits == DestBits && AndOp1 && AndOp1->isOne()) {
1456 DebugLoc DL = N->getDebugLoc();
1457 return DAG.getNode(ISD::SUB, DL, VT, N->getOperand(0), AndOp0);
1458 }
1459 }
1460
Benjamin Kramerf50125e2010-12-22 23:17:45 +00001461 // add (sext i1), X -> sub X, (zext i1)
1462 if (N0.getOpcode() == ISD::SIGN_EXTEND &&
1463 N0.getOperand(0).getValueType() == MVT::i1 &&
1464 !TLI.isOperationLegal(ISD::SIGN_EXTEND, MVT::i1)) {
1465 DebugLoc DL = N->getDebugLoc();
1466 SDValue ZExt = DAG.getNode(ISD::ZERO_EXTEND, DL, VT, N0.getOperand(0));
1467 return DAG.getNode(ISD::SUB, DL, VT, N1, ZExt);
1468 }
1469
Benjamin Kramer74666782011-02-26 22:48:07 +00001470 // add (adde 0, 0, glue), X -> adde X, 0, glue
1471 if (N0->hasOneUse() && isCarryMaterialization(N0))
1472 return DAG.getNode(ISD::ADDE, N->getDebugLoc(),
1473 DAG.getVTList(VT, MVT::Glue), N1, N0.getOperand(0),
1474 N0.getOperand(2));
1475
1476 // add X, (adde 0, 0, glue) -> adde X, 0, glue
1477 if (N1->hasOneUse() && isCarryMaterialization(N1))
1478 return DAG.getNode(ISD::ADDE, N->getDebugLoc(),
1479 DAG.getVTList(VT, MVT::Glue), N0, N1.getOperand(0),
1480 N1.getOperand(2));
1481
Evan Chengb3a3d5e2010-04-28 07:10:39 +00001482 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00001483}
1484
Dan Gohman475871a2008-07-27 21:46:04 +00001485SDValue DAGCombiner::visitADDC(SDNode *N) {
1486 SDValue N0 = N->getOperand(0);
1487 SDValue N1 = N->getOperand(1);
Chris Lattner91153682007-03-04 20:03:15 +00001488 ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0);
1489 ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1);
Owen Andersone50ed302009-08-10 22:56:29 +00001490 EVT VT = N0.getValueType();
Scott Michelfdc40a02009-02-17 22:15:04 +00001491
Chris Lattner91153682007-03-04 20:03:15 +00001492 // If the flag result is dead, turn this into an ADD.
1493 if (N->hasNUsesOfValue(0, 1))
Bill Wendling14036c02009-01-30 02:38:00 +00001494 return CombineTo(N, DAG.getNode(ISD::ADD, N->getDebugLoc(), VT, N1, N0),
Dale Johannesen874ae252009-06-02 03:12:52 +00001495 DAG.getNode(ISD::CARRY_FALSE,
Chris Lattnerf1b4eaf2010-12-21 02:38:05 +00001496 N->getDebugLoc(), MVT::Glue));
Scott Michelfdc40a02009-02-17 22:15:04 +00001497
Chris Lattner91153682007-03-04 20:03:15 +00001498 // canonicalize constant to RHS.
Dan Gohman0a4627d2008-06-23 15:29:14 +00001499 if (N0C && !N1C)
Bill Wendling14036c02009-01-30 02:38:00 +00001500 return DAG.getNode(ISD::ADDC, N->getDebugLoc(), N->getVTList(), N1, N0);
Scott Michelfdc40a02009-02-17 22:15:04 +00001501
Chris Lattnerb6541762007-03-04 20:40:38 +00001502 // fold (addc x, 0) -> x + no carry out
1503 if (N1C && N1C->isNullValue())
Dale Johannesen874ae252009-06-02 03:12:52 +00001504 return CombineTo(N, N0, DAG.getNode(ISD::CARRY_FALSE,
Chris Lattnerf1b4eaf2010-12-21 02:38:05 +00001505 N->getDebugLoc(), MVT::Glue));
Scott Michelfdc40a02009-02-17 22:15:04 +00001506
Dale Johannesen874ae252009-06-02 03:12:52 +00001507 // fold (addc a, b) -> (or a, b), CARRY_FALSE iff a and b share no bits.
Dan Gohman948d8ea2008-02-20 16:33:30 +00001508 APInt LHSZero, LHSOne;
1509 APInt RHSZero, RHSOne;
Dan Gohman5b870af2010-03-02 02:14:38 +00001510 APInt Mask = APInt::getAllOnesValue(VT.getScalarType().getSizeInBits());
Dan Gohmanea859be2007-06-22 14:59:07 +00001511 DAG.ComputeMaskedBits(N0, Mask, LHSZero, LHSOne);
Bill Wendling14036c02009-01-30 02:38:00 +00001512
Dan Gohman948d8ea2008-02-20 16:33:30 +00001513 if (LHSZero.getBoolValue()) {
Dan Gohmanea859be2007-06-22 14:59:07 +00001514 DAG.ComputeMaskedBits(N1, Mask, RHSZero, RHSOne);
Scott Michelfdc40a02009-02-17 22:15:04 +00001515
Chris Lattnerb6541762007-03-04 20:40:38 +00001516 // If all possibly-set bits on the LHS are clear on the RHS, return an OR.
1517 // If all possibly-set bits on the RHS are clear on the LHS, return an OR.
1518 if ((RHSZero & (~LHSZero & Mask)) == (~LHSZero & Mask) ||
1519 (LHSZero & (~RHSZero & Mask)) == (~RHSZero & Mask))
Bill Wendling14036c02009-01-30 02:38:00 +00001520 return CombineTo(N, DAG.getNode(ISD::OR, N->getDebugLoc(), VT, N0, N1),
Dale Johannesen874ae252009-06-02 03:12:52 +00001521 DAG.getNode(ISD::CARRY_FALSE,
Chris Lattnerf1b4eaf2010-12-21 02:38:05 +00001522 N->getDebugLoc(), MVT::Glue));
Chris Lattnerb6541762007-03-04 20:40:38 +00001523 }
Scott Michelfdc40a02009-02-17 22:15:04 +00001524
Benjamin Kramer74666782011-02-26 22:48:07 +00001525 // addc (adde 0, 0, glue), X -> adde X, 0, glue
1526 if (N0->hasOneUse() && isCarryMaterialization(N0))
1527 return DAG.getNode(ISD::ADDE, N->getDebugLoc(), N->getVTList(), N1,
1528 DAG.getConstant(0, VT), N0.getOperand(2));
1529
1530 // addc X, (adde 0, 0, glue) -> adde X, 0, glue
1531 if (N1->hasOneUse() && isCarryMaterialization(N1))
1532 return DAG.getNode(ISD::ADDE, N->getDebugLoc(), N->getVTList(), N0,
1533 DAG.getConstant(0, VT), N1.getOperand(2));
1534
Dan Gohman475871a2008-07-27 21:46:04 +00001535 return SDValue();
Chris Lattner91153682007-03-04 20:03:15 +00001536}
1537
Dan Gohman475871a2008-07-27 21:46:04 +00001538SDValue DAGCombiner::visitADDE(SDNode *N) {
1539 SDValue N0 = N->getOperand(0);
1540 SDValue N1 = N->getOperand(1);
1541 SDValue CarryIn = N->getOperand(2);
Chris Lattner91153682007-03-04 20:03:15 +00001542 ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0);
1543 ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1);
Scott Michelfdc40a02009-02-17 22:15:04 +00001544
Benjamin Kramer74666782011-02-26 22:48:07 +00001545 // If both operands are null we know that carry out will always be false.
1546 if (N0C && N0C->isNullValue() && N0 == N1)
1547 DAG.ReplaceAllUsesOfValueWith(SDValue(N, 1), DAG.getNode(ISD::CARRY_FALSE,
1548 N->getDebugLoc(),
1549 MVT::Glue));
1550
Chris Lattner91153682007-03-04 20:03:15 +00001551 // canonicalize constant to RHS
Dan Gohman0a4627d2008-06-23 15:29:14 +00001552 if (N0C && !N1C)
Bill Wendling14036c02009-01-30 02:38:00 +00001553 return DAG.getNode(ISD::ADDE, N->getDebugLoc(), N->getVTList(),
1554 N1, N0, CarryIn);
Scott Michelfdc40a02009-02-17 22:15:04 +00001555
Chris Lattnerb6541762007-03-04 20:40:38 +00001556 // fold (adde x, y, false) -> (addc x, y)
Dale Johannesen874ae252009-06-02 03:12:52 +00001557 if (CarryIn.getOpcode() == ISD::CARRY_FALSE)
1558 return DAG.getNode(ISD::ADDC, N->getDebugLoc(), N->getVTList(), N1, N0);
Scott Michelfdc40a02009-02-17 22:15:04 +00001559
Dan Gohman475871a2008-07-27 21:46:04 +00001560 return SDValue();
Chris Lattner91153682007-03-04 20:03:15 +00001561}
1562
Eric Christopher7bccf6a2011-02-16 04:50:12 +00001563// Since it may not be valid to emit a fold to zero for vector initializers
1564// check if we can before folding.
1565static SDValue tryFoldToZero(DebugLoc DL, const TargetLowering &TLI, EVT VT,
Owen Anderson95771af2011-02-25 21:41:48 +00001566 SelectionDAG &DAG, bool LegalOperations) {
Eric Christopher7bccf6a2011-02-16 04:50:12 +00001567 if (!VT.isVector()) {
1568 return DAG.getConstant(0, VT);
1569 } else if (!LegalOperations || TLI.isOperationLegal(ISD::BUILD_VECTOR, VT)) {
1570 // Produce a vector of zeros.
1571 SDValue El = DAG.getConstant(0, VT.getVectorElementType());
1572 std::vector<SDValue> Ops(VT.getVectorNumElements(), El);
1573 return DAG.getNode(ISD::BUILD_VECTOR, DL, VT,
1574 &Ops[0], Ops.size());
1575 }
1576 return SDValue();
1577}
1578
Dan Gohman475871a2008-07-27 21:46:04 +00001579SDValue DAGCombiner::visitSUB(SDNode *N) {
1580 SDValue N0 = N->getOperand(0);
1581 SDValue N1 = N->getOperand(1);
Gabor Greifba36cb52008-08-28 21:40:38 +00001582 ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0.getNode());
1583 ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1.getNode());
Owen Andersone50ed302009-08-10 22:56:29 +00001584 EVT VT = N0.getValueType();
Scott Michelfdc40a02009-02-17 22:15:04 +00001585
Dan Gohman7f321562007-06-25 16:23:39 +00001586 // fold vector ops
Duncan Sands83ec4b62008-06-06 12:08:01 +00001587 if (VT.isVector()) {
Dan Gohman475871a2008-07-27 21:46:04 +00001588 SDValue FoldedVOp = SimplifyVBinOp(N);
Gabor Greifba36cb52008-08-28 21:40:38 +00001589 if (FoldedVOp.getNode()) return FoldedVOp;
Dan Gohman05d92fe2007-07-13 20:03:40 +00001590 }
Bill Wendling2476e5d2008-12-10 22:36:00 +00001591
Chris Lattner854077d2005-10-17 01:07:11 +00001592 // fold (sub x, x) -> 0
Eric Christopher169e1552011-02-16 01:10:03 +00001593 // FIXME: Refactor this and xor and other similar operations together.
Eric Christopher7bccf6a2011-02-16 04:50:12 +00001594 if (N0 == N1)
1595 return tryFoldToZero(N->getDebugLoc(), TLI, VT, DAG, LegalOperations);
Nate Begeman1d4d4142005-09-01 00:19:25 +00001596 // fold (sub c1, c2) -> c1-c2
Nate Begeman646d7e22005-09-02 21:18:40 +00001597 if (N0C && N1C)
Bill Wendlingf3cbca22008-09-24 10:25:02 +00001598 return DAG.FoldConstantArithmetic(ISD::SUB, VT, N0C, N1C);
Chris Lattner05b57432005-10-11 06:07:15 +00001599 // fold (sub x, c) -> (add x, -c)
1600 if (N1C)
Bill Wendlingb0702e02009-01-30 02:42:10 +00001601 return DAG.getNode(ISD::ADD, N->getDebugLoc(), VT, N0,
Dan Gohman002e5d02008-03-13 22:13:53 +00001602 DAG.getConstant(-N1C->getAPIntValue(), VT));
Evan Cheng1ad0e8b2010-01-18 21:38:44 +00001603 // Canonicalize (sub -1, x) -> ~x, i.e. (xor x, -1)
1604 if (N0C && N0C->isAllOnesValue())
1605 return DAG.getNode(ISD::XOR, N->getDebugLoc(), VT, N1, N0);
Benjamin Kramer2c94b422011-01-29 12:34:05 +00001606 // fold A-(A-B) -> B
1607 if (N1.getOpcode() == ISD::SUB && N0 == N1.getOperand(0))
1608 return N1.getOperand(1);
Nate Begeman1d4d4142005-09-01 00:19:25 +00001609 // fold (A+B)-A -> B
Chris Lattner01b3d732005-09-28 22:28:18 +00001610 if (N0.getOpcode() == ISD::ADD && N0.getOperand(0) == N1)
Nate Begeman83e75ec2005-09-06 04:43:02 +00001611 return N0.getOperand(1);
Nate Begeman1d4d4142005-09-01 00:19:25 +00001612 // fold (A+B)-B -> A
Chris Lattner01b3d732005-09-28 22:28:18 +00001613 if (N0.getOpcode() == ISD::ADD && N0.getOperand(1) == N1)
Scott Michelfdc40a02009-02-17 22:15:04 +00001614 return N0.getOperand(0);
Dale Johannesen7c7bc722008-12-23 23:47:22 +00001615 // fold ((A+(B+or-C))-B) -> A+or-C
Dale Johannesenfd3b7b72008-12-16 22:13:49 +00001616 if (N0.getOpcode() == ISD::ADD &&
Dale Johannesenf9cbc1f2008-12-23 23:01:27 +00001617 (N0.getOperand(1).getOpcode() == ISD::SUB ||
1618 N0.getOperand(1).getOpcode() == ISD::ADD) &&
Dale Johannesenfd3b7b72008-12-16 22:13:49 +00001619 N0.getOperand(1).getOperand(0) == N1)
Bill Wendlingb0702e02009-01-30 02:42:10 +00001620 return DAG.getNode(N0.getOperand(1).getOpcode(), N->getDebugLoc(), VT,
1621 N0.getOperand(0), N0.getOperand(1).getOperand(1));
Dale Johannesenf9cbc1f2008-12-23 23:01:27 +00001622 // fold ((A+(C+B))-B) -> A+C
1623 if (N0.getOpcode() == ISD::ADD &&
1624 N0.getOperand(1).getOpcode() == ISD::ADD &&
1625 N0.getOperand(1).getOperand(1) == N1)
Bill Wendlingb0702e02009-01-30 02:42:10 +00001626 return DAG.getNode(ISD::ADD, N->getDebugLoc(), VT,
1627 N0.getOperand(0), N0.getOperand(1).getOperand(0));
Dale Johannesen58e39b02008-12-23 01:59:54 +00001628 // fold ((A-(B-C))-C) -> A-B
1629 if (N0.getOpcode() == ISD::SUB &&
1630 N0.getOperand(1).getOpcode() == ISD::SUB &&
1631 N0.getOperand(1).getOperand(1) == N1)
Bill Wendlingb0702e02009-01-30 02:42:10 +00001632 return DAG.getNode(ISD::SUB, N->getDebugLoc(), VT,
1633 N0.getOperand(0), N0.getOperand(1).getOperand(0));
Bill Wendlingb0702e02009-01-30 02:42:10 +00001634
Dan Gohman613e0d82007-07-03 14:03:57 +00001635 // If either operand of a sub is undef, the result is undef
Dan Gohman70fb1ae2007-07-10 15:19:29 +00001636 if (N0.getOpcode() == ISD::UNDEF)
1637 return N0;
1638 if (N1.getOpcode() == ISD::UNDEF)
1639 return N1;
Dan Gohman7f321562007-06-25 16:23:39 +00001640
Dan Gohman6520e202008-10-18 02:06:02 +00001641 // If the relocation model supports it, consider symbol offsets.
1642 if (GlobalAddressSDNode *GA = dyn_cast<GlobalAddressSDNode>(N0))
Duncan Sands25cf2272008-11-24 14:53:14 +00001643 if (!LegalOperations && TLI.isOffsetFoldingLegal(GA)) {
Dan Gohman6520e202008-10-18 02:06:02 +00001644 // fold (sub Sym, c) -> Sym-c
1645 if (N1C && GA->getOpcode() == ISD::GlobalAddress)
Devang Patel0d881da2010-07-06 22:08:15 +00001646 return DAG.getGlobalAddress(GA->getGlobal(), N1C->getDebugLoc(), VT,
Dan Gohman6520e202008-10-18 02:06:02 +00001647 GA->getOffset() -
1648 (uint64_t)N1C->getSExtValue());
1649 // fold (sub Sym+c1, Sym+c2) -> c1-c2
1650 if (GlobalAddressSDNode *GB = dyn_cast<GlobalAddressSDNode>(N1))
1651 if (GA->getGlobal() == GB->getGlobal())
1652 return DAG.getConstant((uint64_t)GA->getOffset() - GB->getOffset(),
1653 VT);
1654 }
1655
Evan Chengb3a3d5e2010-04-28 07:10:39 +00001656 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00001657}
1658
Dan Gohman475871a2008-07-27 21:46:04 +00001659SDValue DAGCombiner::visitMUL(SDNode *N) {
1660 SDValue N0 = N->getOperand(0);
1661 SDValue N1 = N->getOperand(1);
Nate Begeman646d7e22005-09-02 21:18:40 +00001662 ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0);
1663 ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1);
Owen Andersone50ed302009-08-10 22:56:29 +00001664 EVT VT = N0.getValueType();
Scott Michelfdc40a02009-02-17 22:15:04 +00001665
Dan Gohman7f321562007-06-25 16:23:39 +00001666 // fold vector ops
Duncan Sands83ec4b62008-06-06 12:08:01 +00001667 if (VT.isVector()) {
Dan Gohman475871a2008-07-27 21:46:04 +00001668 SDValue FoldedVOp = SimplifyVBinOp(N);
Gabor Greifba36cb52008-08-28 21:40:38 +00001669 if (FoldedVOp.getNode()) return FoldedVOp;
Dan Gohman05d92fe2007-07-13 20:03:40 +00001670 }
Scott Michelfdc40a02009-02-17 22:15:04 +00001671
Dan Gohman613e0d82007-07-03 14:03:57 +00001672 // fold (mul x, undef) -> 0
Dan Gohmand595b5f2007-07-10 14:20:37 +00001673 if (N0.getOpcode() == ISD::UNDEF || N1.getOpcode() == ISD::UNDEF)
Dan Gohman613e0d82007-07-03 14:03:57 +00001674 return DAG.getConstant(0, VT);
Nate Begeman1d4d4142005-09-01 00:19:25 +00001675 // fold (mul c1, c2) -> c1*c2
Nate Begeman646d7e22005-09-02 21:18:40 +00001676 if (N0C && N1C)
Bill Wendlingf3cbca22008-09-24 10:25:02 +00001677 return DAG.FoldConstantArithmetic(ISD::MUL, VT, N0C, N1C);
Nate Begeman99801192005-09-07 23:25:52 +00001678 // canonicalize constant to RHS
Nate Begemana0e221d2005-10-18 00:28:13 +00001679 if (N0C && !N1C)
Bill Wendling9c8148a2009-01-30 02:45:56 +00001680 return DAG.getNode(ISD::MUL, N->getDebugLoc(), VT, N1, N0);
Nate Begeman1d4d4142005-09-01 00:19:25 +00001681 // fold (mul x, 0) -> 0
Nate Begeman646d7e22005-09-02 21:18:40 +00001682 if (N1C && N1C->isNullValue())
Nate Begeman83e75ec2005-09-06 04:43:02 +00001683 return N1;
Nate Begeman1d4d4142005-09-01 00:19:25 +00001684 // fold (mul x, -1) -> 0-x
Nate Begeman646d7e22005-09-02 21:18:40 +00001685 if (N1C && N1C->isAllOnesValue())
Bill Wendling9c8148a2009-01-30 02:45:56 +00001686 return DAG.getNode(ISD::SUB, N->getDebugLoc(), VT,
1687 DAG.getConstant(0, VT), N0);
Nate Begeman1d4d4142005-09-01 00:19:25 +00001688 // fold (mul x, (1 << c)) -> x << c
Dan Gohman002e5d02008-03-13 22:13:53 +00001689 if (N1C && N1C->getAPIntValue().isPowerOf2())
Bill Wendling9c8148a2009-01-30 02:45:56 +00001690 return DAG.getNode(ISD::SHL, N->getDebugLoc(), VT, N0,
Dan Gohman002e5d02008-03-13 22:13:53 +00001691 DAG.getConstant(N1C->getAPIntValue().logBase2(),
Owen Anderson95771af2011-02-25 21:41:48 +00001692 getShiftAmountTy(N0.getValueType())));
Chris Lattner3e6099b2005-10-30 06:41:49 +00001693 // fold (mul x, -(1 << c)) -> -(x << c) or (-x) << c
Chris Lattner66b8bc32009-03-09 20:22:18 +00001694 if (N1C && (-N1C->getAPIntValue()).isPowerOf2()) {
1695 unsigned Log2Val = (-N1C->getAPIntValue()).logBase2();
Scott Michelfdc40a02009-02-17 22:15:04 +00001696 // FIXME: If the input is something that is easily negated (e.g. a
Chris Lattner3e6099b2005-10-30 06:41:49 +00001697 // single-use add), we should put the negate there.
Bill Wendling9c8148a2009-01-30 02:45:56 +00001698 return DAG.getNode(ISD::SUB, N->getDebugLoc(), VT,
1699 DAG.getConstant(0, VT),
Bill Wendling73e16b22009-01-30 02:49:26 +00001700 DAG.getNode(ISD::SHL, N->getDebugLoc(), VT, N0,
Owen Anderson95771af2011-02-25 21:41:48 +00001701 DAG.getConstant(Log2Val,
1702 getShiftAmountTy(N0.getValueType()))));
Chris Lattner66b8bc32009-03-09 20:22:18 +00001703 }
Chris Lattner0b1a85f2006-03-01 03:44:24 +00001704 // (mul (shl X, c1), c2) -> (mul X, c2 << c1)
Bill Wendling73e16b22009-01-30 02:49:26 +00001705 if (N1C && N0.getOpcode() == ISD::SHL &&
Chris Lattner0b1a85f2006-03-01 03:44:24 +00001706 isa<ConstantSDNode>(N0.getOperand(1))) {
Bill Wendling9c8148a2009-01-30 02:45:56 +00001707 SDValue C3 = DAG.getNode(ISD::SHL, N->getDebugLoc(), VT,
1708 N1, N0.getOperand(1));
Gabor Greifba36cb52008-08-28 21:40:38 +00001709 AddToWorkList(C3.getNode());
Bill Wendling9c8148a2009-01-30 02:45:56 +00001710 return DAG.getNode(ISD::MUL, N->getDebugLoc(), VT,
1711 N0.getOperand(0), C3);
Chris Lattner0b1a85f2006-03-01 03:44:24 +00001712 }
Scott Michelfdc40a02009-02-17 22:15:04 +00001713
Chris Lattner0b1a85f2006-03-01 03:44:24 +00001714 // Change (mul (shl X, C), Y) -> (shl (mul X, Y), C) when the shift has one
1715 // use.
1716 {
Dan Gohman475871a2008-07-27 21:46:04 +00001717 SDValue Sh(0,0), Y(0,0);
Chris Lattner0b1a85f2006-03-01 03:44:24 +00001718 // Check for both (mul (shl X, C), Y) and (mul Y, (shl X, C)).
1719 if (N0.getOpcode() == ISD::SHL && isa<ConstantSDNode>(N0.getOperand(1)) &&
Gabor Greifba36cb52008-08-28 21:40:38 +00001720 N0.getNode()->hasOneUse()) {
Chris Lattner0b1a85f2006-03-01 03:44:24 +00001721 Sh = N0; Y = N1;
Scott Michelfdc40a02009-02-17 22:15:04 +00001722 } else if (N1.getOpcode() == ISD::SHL &&
Gabor Greif12632d22008-08-30 19:29:20 +00001723 isa<ConstantSDNode>(N1.getOperand(1)) &&
1724 N1.getNode()->hasOneUse()) {
Chris Lattner0b1a85f2006-03-01 03:44:24 +00001725 Sh = N1; Y = N0;
1726 }
Bill Wendling73e16b22009-01-30 02:49:26 +00001727
Gabor Greifba36cb52008-08-28 21:40:38 +00001728 if (Sh.getNode()) {
Bill Wendling9c8148a2009-01-30 02:45:56 +00001729 SDValue Mul = DAG.getNode(ISD::MUL, N->getDebugLoc(), VT,
1730 Sh.getOperand(0), Y);
1731 return DAG.getNode(ISD::SHL, N->getDebugLoc(), VT,
1732 Mul, Sh.getOperand(1));
Chris Lattner0b1a85f2006-03-01 03:44:24 +00001733 }
1734 }
Bill Wendling73e16b22009-01-30 02:49:26 +00001735
Chris Lattnera1deca32006-03-04 23:33:26 +00001736 // fold (mul (add x, c1), c2) -> (add (mul x, c2), c1*c2)
Scott Michelfdc40a02009-02-17 22:15:04 +00001737 if (N1C && N0.getOpcode() == ISD::ADD && N0.getNode()->hasOneUse() &&
Bill Wendling9c8148a2009-01-30 02:45:56 +00001738 isa<ConstantSDNode>(N0.getOperand(1)))
1739 return DAG.getNode(ISD::ADD, N->getDebugLoc(), VT,
1740 DAG.getNode(ISD::MUL, N0.getDebugLoc(), VT,
1741 N0.getOperand(0), N1),
1742 DAG.getNode(ISD::MUL, N1.getDebugLoc(), VT,
1743 N0.getOperand(1), N1));
Scott Michelfdc40a02009-02-17 22:15:04 +00001744
Nate Begemancd4d58c2006-02-03 06:46:56 +00001745 // reassociate mul
Bill Wendling35247c32009-01-30 00:45:56 +00001746 SDValue RMUL = ReassociateOps(ISD::MUL, N->getDebugLoc(), N0, N1);
Gabor Greifba36cb52008-08-28 21:40:38 +00001747 if (RMUL.getNode() != 0)
Nate Begemancd4d58c2006-02-03 06:46:56 +00001748 return RMUL;
Dan Gohman7f321562007-06-25 16:23:39 +00001749
Evan Chengb3a3d5e2010-04-28 07:10:39 +00001750 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00001751}
1752
Dan Gohman475871a2008-07-27 21:46:04 +00001753SDValue DAGCombiner::visitSDIV(SDNode *N) {
1754 SDValue N0 = N->getOperand(0);
1755 SDValue N1 = N->getOperand(1);
Gabor Greifba36cb52008-08-28 21:40:38 +00001756 ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0.getNode());
1757 ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1.getNode());
Owen Andersone50ed302009-08-10 22:56:29 +00001758 EVT VT = N->getValueType(0);
Nate Begeman1d4d4142005-09-01 00:19:25 +00001759
Dan Gohman7f321562007-06-25 16:23:39 +00001760 // fold vector ops
Duncan Sands83ec4b62008-06-06 12:08:01 +00001761 if (VT.isVector()) {
Dan Gohman475871a2008-07-27 21:46:04 +00001762 SDValue FoldedVOp = SimplifyVBinOp(N);
Gabor Greifba36cb52008-08-28 21:40:38 +00001763 if (FoldedVOp.getNode()) return FoldedVOp;
Dan Gohman05d92fe2007-07-13 20:03:40 +00001764 }
Scott Michelfdc40a02009-02-17 22:15:04 +00001765
Nate Begeman1d4d4142005-09-01 00:19:25 +00001766 // fold (sdiv c1, c2) -> c1/c2
Nate Begeman646d7e22005-09-02 21:18:40 +00001767 if (N0C && N1C && !N1C->isNullValue())
Bill Wendlingf3cbca22008-09-24 10:25:02 +00001768 return DAG.FoldConstantArithmetic(ISD::SDIV, VT, N0C, N1C);
Nate Begeman405e3ec2005-10-21 00:02:42 +00001769 // fold (sdiv X, 1) -> X
Dan Gohman7810bfe2008-09-26 21:54:37 +00001770 if (N1C && N1C->getSExtValue() == 1LL)
Nate Begeman405e3ec2005-10-21 00:02:42 +00001771 return N0;
1772 // fold (sdiv X, -1) -> 0-X
1773 if (N1C && N1C->isAllOnesValue())
Bill Wendling944d34b2009-01-30 02:52:17 +00001774 return DAG.getNode(ISD::SUB, N->getDebugLoc(), VT,
1775 DAG.getConstant(0, VT), N0);
Chris Lattner094c8fc2005-10-07 06:10:46 +00001776 // If we know the sign bits of both operands are zero, strength reduce to a
1777 // udiv instead. Handles (X&15) /s 4 -> X&15 >> 2
Duncan Sands83ec4b62008-06-06 12:08:01 +00001778 if (!VT.isVector()) {
Dan Gohman2e68b6f2008-02-25 21:11:39 +00001779 if (DAG.SignBitIsZero(N1) && DAG.SignBitIsZero(N0))
Bill Wendling944d34b2009-01-30 02:52:17 +00001780 return DAG.getNode(ISD::UDIV, N->getDebugLoc(), N1.getValueType(),
1781 N0, N1);
Chris Lattnerf32aac32008-01-27 23:32:17 +00001782 }
Nate Begemancd6a6ed2006-02-17 07:26:20 +00001783 // fold (sdiv X, pow2) -> simple ops after legalize
Dan Gohman002e5d02008-03-13 22:13:53 +00001784 if (N1C && !N1C->isNullValue() && !TLI.isIntDivCheap() &&
Scott Michelfdc40a02009-02-17 22:15:04 +00001785 (isPowerOf2_64(N1C->getSExtValue()) ||
Dan Gohman7810bfe2008-09-26 21:54:37 +00001786 isPowerOf2_64(-N1C->getSExtValue()))) {
Nate Begeman405e3ec2005-10-21 00:02:42 +00001787 // If dividing by powers of two is cheap, then don't perform the following
1788 // fold.
1789 if (TLI.isPow2DivCheap())
Dan Gohman475871a2008-07-27 21:46:04 +00001790 return SDValue();
Bill Wendling944d34b2009-01-30 02:52:17 +00001791
Dan Gohman7810bfe2008-09-26 21:54:37 +00001792 int64_t pow2 = N1C->getSExtValue();
Nate Begeman405e3ec2005-10-21 00:02:42 +00001793 int64_t abs2 = pow2 > 0 ? pow2 : -pow2;
Chris Lattner8f4880b2006-02-16 08:02:36 +00001794 unsigned lg2 = Log2_64(abs2);
Bill Wendling944d34b2009-01-30 02:52:17 +00001795
Chris Lattner8f4880b2006-02-16 08:02:36 +00001796 // Splat the sign bit into the register
Bill Wendling944d34b2009-01-30 02:52:17 +00001797 SDValue SGN = DAG.getNode(ISD::SRA, N->getDebugLoc(), VT, N0,
1798 DAG.getConstant(VT.getSizeInBits()-1,
Owen Anderson95771af2011-02-25 21:41:48 +00001799 getShiftAmountTy(N0.getValueType())));
Gabor Greifba36cb52008-08-28 21:40:38 +00001800 AddToWorkList(SGN.getNode());
Bill Wendling944d34b2009-01-30 02:52:17 +00001801
Chris Lattner8f4880b2006-02-16 08:02:36 +00001802 // Add (N0 < 0) ? abs2 - 1 : 0;
Bill Wendling944d34b2009-01-30 02:52:17 +00001803 SDValue SRL = DAG.getNode(ISD::SRL, N->getDebugLoc(), VT, SGN,
1804 DAG.getConstant(VT.getSizeInBits() - lg2,
Owen Anderson95771af2011-02-25 21:41:48 +00001805 getShiftAmountTy(SGN.getValueType())));
Bill Wendling944d34b2009-01-30 02:52:17 +00001806 SDValue ADD = DAG.getNode(ISD::ADD, N->getDebugLoc(), VT, N0, SRL);
Gabor Greifba36cb52008-08-28 21:40:38 +00001807 AddToWorkList(SRL.getNode());
1808 AddToWorkList(ADD.getNode()); // Divide by pow2
Bill Wendling944d34b2009-01-30 02:52:17 +00001809 SDValue SRA = DAG.getNode(ISD::SRA, N->getDebugLoc(), VT, ADD,
Owen Anderson95771af2011-02-25 21:41:48 +00001810 DAG.getConstant(lg2, getShiftAmountTy(ADD.getValueType())));
Bill Wendling944d34b2009-01-30 02:52:17 +00001811
Nate Begeman405e3ec2005-10-21 00:02:42 +00001812 // If we're dividing by a positive value, we're done. Otherwise, we must
1813 // negate the result.
1814 if (pow2 > 0)
1815 return SRA;
Bill Wendling944d34b2009-01-30 02:52:17 +00001816
Gabor Greifba36cb52008-08-28 21:40:38 +00001817 AddToWorkList(SRA.getNode());
Bill Wendling944d34b2009-01-30 02:52:17 +00001818 return DAG.getNode(ISD::SUB, N->getDebugLoc(), VT,
1819 DAG.getConstant(0, VT), SRA);
Nate Begeman405e3ec2005-10-21 00:02:42 +00001820 }
Bill Wendling944d34b2009-01-30 02:52:17 +00001821
Nate Begeman69575232005-10-20 02:15:44 +00001822 // if integer divide is expensive and we satisfy the requirements, emit an
1823 // alternate sequence.
Scott Michelfdc40a02009-02-17 22:15:04 +00001824 if (N1C && (N1C->getSExtValue() < -1 || N1C->getSExtValue() > 1) &&
Chris Lattnere9936d12005-10-22 18:50:15 +00001825 !TLI.isIntDivCheap()) {
Dan Gohman475871a2008-07-27 21:46:04 +00001826 SDValue Op = BuildSDIV(N);
Gabor Greifba36cb52008-08-28 21:40:38 +00001827 if (Op.getNode()) return Op;
Nate Begeman69575232005-10-20 02:15:44 +00001828 }
Dan Gohman7f321562007-06-25 16:23:39 +00001829
Dan Gohman613e0d82007-07-03 14:03:57 +00001830 // undef / X -> 0
1831 if (N0.getOpcode() == ISD::UNDEF)
1832 return DAG.getConstant(0, VT);
1833 // X / undef -> undef
1834 if (N1.getOpcode() == ISD::UNDEF)
1835 return N1;
Dan Gohman7f321562007-06-25 16:23:39 +00001836
Dan Gohman475871a2008-07-27 21:46:04 +00001837 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00001838}
1839
Dan Gohman475871a2008-07-27 21:46:04 +00001840SDValue DAGCombiner::visitUDIV(SDNode *N) {
1841 SDValue N0 = N->getOperand(0);
1842 SDValue N1 = N->getOperand(1);
Gabor Greifba36cb52008-08-28 21:40:38 +00001843 ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0.getNode());
1844 ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1.getNode());
Owen Andersone50ed302009-08-10 22:56:29 +00001845 EVT VT = N->getValueType(0);
Scott Michelfdc40a02009-02-17 22:15:04 +00001846
Dan Gohman7f321562007-06-25 16:23:39 +00001847 // fold vector ops
Duncan Sands83ec4b62008-06-06 12:08:01 +00001848 if (VT.isVector()) {
Dan Gohman475871a2008-07-27 21:46:04 +00001849 SDValue FoldedVOp = SimplifyVBinOp(N);
Gabor Greifba36cb52008-08-28 21:40:38 +00001850 if (FoldedVOp.getNode()) return FoldedVOp;
Dan Gohman05d92fe2007-07-13 20:03:40 +00001851 }
Scott Michelfdc40a02009-02-17 22:15:04 +00001852
Nate Begeman1d4d4142005-09-01 00:19:25 +00001853 // fold (udiv c1, c2) -> c1/c2
Nate Begeman646d7e22005-09-02 21:18:40 +00001854 if (N0C && N1C && !N1C->isNullValue())
Bill Wendlingf3cbca22008-09-24 10:25:02 +00001855 return DAG.FoldConstantArithmetic(ISD::UDIV, VT, N0C, N1C);
Nate Begeman1d4d4142005-09-01 00:19:25 +00001856 // fold (udiv x, (1 << c)) -> x >>u c
Dan Gohman002e5d02008-03-13 22:13:53 +00001857 if (N1C && N1C->getAPIntValue().isPowerOf2())
Scott Michelfdc40a02009-02-17 22:15:04 +00001858 return DAG.getNode(ISD::SRL, N->getDebugLoc(), VT, N0,
Dan Gohman002e5d02008-03-13 22:13:53 +00001859 DAG.getConstant(N1C->getAPIntValue().logBase2(),
Owen Anderson95771af2011-02-25 21:41:48 +00001860 getShiftAmountTy(N0.getValueType())));
Nate Begemanfb5e4bd2006-02-05 07:20:23 +00001861 // fold (udiv x, (shl c, y)) -> x >>u (log2(c)+y) iff c is power of 2
1862 if (N1.getOpcode() == ISD::SHL) {
1863 if (ConstantSDNode *SHC = dyn_cast<ConstantSDNode>(N1.getOperand(0))) {
Dan Gohman002e5d02008-03-13 22:13:53 +00001864 if (SHC->getAPIntValue().isPowerOf2()) {
Owen Andersone50ed302009-08-10 22:56:29 +00001865 EVT ADDVT = N1.getOperand(1).getValueType();
Bill Wendling07d85142009-01-30 02:55:25 +00001866 SDValue Add = DAG.getNode(ISD::ADD, N->getDebugLoc(), ADDVT,
1867 N1.getOperand(1),
1868 DAG.getConstant(SHC->getAPIntValue()
1869 .logBase2(),
1870 ADDVT));
Gabor Greifba36cb52008-08-28 21:40:38 +00001871 AddToWorkList(Add.getNode());
Bill Wendling07d85142009-01-30 02:55:25 +00001872 return DAG.getNode(ISD::SRL, N->getDebugLoc(), VT, N0, Add);
Nate Begemanfb5e4bd2006-02-05 07:20:23 +00001873 }
1874 }
1875 }
Nate Begeman69575232005-10-20 02:15:44 +00001876 // fold (udiv x, c) -> alternate
Dan Gohman002e5d02008-03-13 22:13:53 +00001877 if (N1C && !N1C->isNullValue() && !TLI.isIntDivCheap()) {
Dan Gohman475871a2008-07-27 21:46:04 +00001878 SDValue Op = BuildUDIV(N);
Gabor Greifba36cb52008-08-28 21:40:38 +00001879 if (Op.getNode()) return Op;
Chris Lattnere9936d12005-10-22 18:50:15 +00001880 }
Dan Gohman7f321562007-06-25 16:23:39 +00001881
Dan Gohman613e0d82007-07-03 14:03:57 +00001882 // undef / X -> 0
1883 if (N0.getOpcode() == ISD::UNDEF)
1884 return DAG.getConstant(0, VT);
1885 // X / undef -> undef
1886 if (N1.getOpcode() == ISD::UNDEF)
1887 return N1;
Dan Gohman7f321562007-06-25 16:23:39 +00001888
Dan Gohman475871a2008-07-27 21:46:04 +00001889 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00001890}
1891
Dan Gohman475871a2008-07-27 21:46:04 +00001892SDValue DAGCombiner::visitSREM(SDNode *N) {
1893 SDValue N0 = N->getOperand(0);
1894 SDValue N1 = N->getOperand(1);
Nate Begeman646d7e22005-09-02 21:18:40 +00001895 ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0);
1896 ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1);
Owen Andersone50ed302009-08-10 22:56:29 +00001897 EVT VT = N->getValueType(0);
Scott Michelfdc40a02009-02-17 22:15:04 +00001898
Nate Begeman1d4d4142005-09-01 00:19:25 +00001899 // fold (srem c1, c2) -> c1%c2
Nate Begeman646d7e22005-09-02 21:18:40 +00001900 if (N0C && N1C && !N1C->isNullValue())
Bill Wendlingf3cbca22008-09-24 10:25:02 +00001901 return DAG.FoldConstantArithmetic(ISD::SREM, VT, N0C, N1C);
Nate Begeman07ed4172005-10-10 21:26:48 +00001902 // If we know the sign bits of both operands are zero, strength reduce to a
1903 // urem instead. Handles (X & 0x0FFFFFFF) %s 16 -> X&15
Duncan Sands83ec4b62008-06-06 12:08:01 +00001904 if (!VT.isVector()) {
Dan Gohman2e68b6f2008-02-25 21:11:39 +00001905 if (DAG.SignBitIsZero(N1) && DAG.SignBitIsZero(N0))
Bill Wendling6d3bf8c2009-01-30 02:57:00 +00001906 return DAG.getNode(ISD::UREM, N->getDebugLoc(), VT, N0, N1);
Chris Lattneree339f42008-01-27 23:21:58 +00001907 }
Scott Michelfdc40a02009-02-17 22:15:04 +00001908
Dan Gohman77003042007-11-26 23:46:11 +00001909 // If X/C can be simplified by the division-by-constant logic, lower
1910 // X%C to the equivalent of X-X/C*C.
Chris Lattner26d29902006-10-12 20:58:32 +00001911 if (N1C && !N1C->isNullValue()) {
Bill Wendling6d3bf8c2009-01-30 02:57:00 +00001912 SDValue Div = DAG.getNode(ISD::SDIV, N->getDebugLoc(), VT, N0, N1);
Gabor Greifba36cb52008-08-28 21:40:38 +00001913 AddToWorkList(Div.getNode());
1914 SDValue OptimizedDiv = combine(Div.getNode());
1915 if (OptimizedDiv.getNode() && OptimizedDiv.getNode() != Div.getNode()) {
Bill Wendling6d3bf8c2009-01-30 02:57:00 +00001916 SDValue Mul = DAG.getNode(ISD::MUL, N->getDebugLoc(), VT,
1917 OptimizedDiv, N1);
1918 SDValue Sub = DAG.getNode(ISD::SUB, N->getDebugLoc(), VT, N0, Mul);
Gabor Greifba36cb52008-08-28 21:40:38 +00001919 AddToWorkList(Mul.getNode());
Dan Gohman77003042007-11-26 23:46:11 +00001920 return Sub;
1921 }
Chris Lattner26d29902006-10-12 20:58:32 +00001922 }
Scott Michelfdc40a02009-02-17 22:15:04 +00001923
Dan Gohman613e0d82007-07-03 14:03:57 +00001924 // undef % X -> 0
1925 if (N0.getOpcode() == ISD::UNDEF)
1926 return DAG.getConstant(0, VT);
1927 // X % undef -> undef
1928 if (N1.getOpcode() == ISD::UNDEF)
1929 return N1;
Dan Gohman7f321562007-06-25 16:23:39 +00001930
Dan Gohman475871a2008-07-27 21:46:04 +00001931 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00001932}
1933
Dan Gohman475871a2008-07-27 21:46:04 +00001934SDValue DAGCombiner::visitUREM(SDNode *N) {
1935 SDValue N0 = N->getOperand(0);
1936 SDValue N1 = N->getOperand(1);
Nate Begeman646d7e22005-09-02 21:18:40 +00001937 ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0);
1938 ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1);
Owen Andersone50ed302009-08-10 22:56:29 +00001939 EVT VT = N->getValueType(0);
Scott Michelfdc40a02009-02-17 22:15:04 +00001940
Nate Begeman1d4d4142005-09-01 00:19:25 +00001941 // fold (urem c1, c2) -> c1%c2
Nate Begeman646d7e22005-09-02 21:18:40 +00001942 if (N0C && N1C && !N1C->isNullValue())
Bill Wendlingf3cbca22008-09-24 10:25:02 +00001943 return DAG.FoldConstantArithmetic(ISD::UREM, VT, N0C, N1C);
Nate Begeman07ed4172005-10-10 21:26:48 +00001944 // fold (urem x, pow2) -> (and x, pow2-1)
Dan Gohman002e5d02008-03-13 22:13:53 +00001945 if (N1C && !N1C->isNullValue() && N1C->getAPIntValue().isPowerOf2())
Bill Wendling6d3bf8c2009-01-30 02:57:00 +00001946 return DAG.getNode(ISD::AND, N->getDebugLoc(), VT, N0,
Dan Gohman002e5d02008-03-13 22:13:53 +00001947 DAG.getConstant(N1C->getAPIntValue()-1,VT));
Nate Begemanc031e332006-02-05 07:36:48 +00001948 // fold (urem x, (shl pow2, y)) -> (and x, (add (shl pow2, y), -1))
1949 if (N1.getOpcode() == ISD::SHL) {
1950 if (ConstantSDNode *SHC = dyn_cast<ConstantSDNode>(N1.getOperand(0))) {
Dan Gohman002e5d02008-03-13 22:13:53 +00001951 if (SHC->getAPIntValue().isPowerOf2()) {
Dan Gohman475871a2008-07-27 21:46:04 +00001952 SDValue Add =
Bill Wendling6d3bf8c2009-01-30 02:57:00 +00001953 DAG.getNode(ISD::ADD, N->getDebugLoc(), VT, N1,
Duncan Sands83ec4b62008-06-06 12:08:01 +00001954 DAG.getConstant(APInt::getAllOnesValue(VT.getSizeInBits()),
Dan Gohman002e5d02008-03-13 22:13:53 +00001955 VT));
Gabor Greifba36cb52008-08-28 21:40:38 +00001956 AddToWorkList(Add.getNode());
Bill Wendling6d3bf8c2009-01-30 02:57:00 +00001957 return DAG.getNode(ISD::AND, N->getDebugLoc(), VT, N0, Add);
Nate Begemanc031e332006-02-05 07:36:48 +00001958 }
1959 }
1960 }
Scott Michelfdc40a02009-02-17 22:15:04 +00001961
Dan Gohman77003042007-11-26 23:46:11 +00001962 // If X/C can be simplified by the division-by-constant logic, lower
1963 // X%C to the equivalent of X-X/C*C.
Chris Lattner26d29902006-10-12 20:58:32 +00001964 if (N1C && !N1C->isNullValue()) {
Bill Wendling6d3bf8c2009-01-30 02:57:00 +00001965 SDValue Div = DAG.getNode(ISD::UDIV, N->getDebugLoc(), VT, N0, N1);
Dan Gohman942ca7f2008-09-08 16:59:01 +00001966 AddToWorkList(Div.getNode());
Gabor Greifba36cb52008-08-28 21:40:38 +00001967 SDValue OptimizedDiv = combine(Div.getNode());
1968 if (OptimizedDiv.getNode() && OptimizedDiv.getNode() != Div.getNode()) {
Bill Wendling6d3bf8c2009-01-30 02:57:00 +00001969 SDValue Mul = DAG.getNode(ISD::MUL, N->getDebugLoc(), VT,
1970 OptimizedDiv, N1);
1971 SDValue Sub = DAG.getNode(ISD::SUB, N->getDebugLoc(), VT, N0, Mul);
Gabor Greifba36cb52008-08-28 21:40:38 +00001972 AddToWorkList(Mul.getNode());
Dan Gohman77003042007-11-26 23:46:11 +00001973 return Sub;
1974 }
Chris Lattner26d29902006-10-12 20:58:32 +00001975 }
Scott Michelfdc40a02009-02-17 22:15:04 +00001976
Dan Gohman613e0d82007-07-03 14:03:57 +00001977 // undef % X -> 0
1978 if (N0.getOpcode() == ISD::UNDEF)
1979 return DAG.getConstant(0, VT);
1980 // X % undef -> undef
1981 if (N1.getOpcode() == ISD::UNDEF)
1982 return N1;
Dan Gohman7f321562007-06-25 16:23:39 +00001983
Dan Gohman475871a2008-07-27 21:46:04 +00001984 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00001985}
1986
Dan Gohman475871a2008-07-27 21:46:04 +00001987SDValue DAGCombiner::visitMULHS(SDNode *N) {
1988 SDValue N0 = N->getOperand(0);
1989 SDValue N1 = N->getOperand(1);
Nate Begeman646d7e22005-09-02 21:18:40 +00001990 ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1);
Owen Andersone50ed302009-08-10 22:56:29 +00001991 EVT VT = N->getValueType(0);
Chris Lattnerde1c3602010-12-13 08:39:01 +00001992 DebugLoc DL = N->getDebugLoc();
Scott Michelfdc40a02009-02-17 22:15:04 +00001993
Nate Begeman1d4d4142005-09-01 00:19:25 +00001994 // fold (mulhs x, 0) -> 0
Nate Begeman646d7e22005-09-02 21:18:40 +00001995 if (N1C && N1C->isNullValue())
Nate Begeman83e75ec2005-09-06 04:43:02 +00001996 return N1;
Nate Begeman1d4d4142005-09-01 00:19:25 +00001997 // fold (mulhs x, 1) -> (sra x, size(x)-1)
Dan Gohman002e5d02008-03-13 22:13:53 +00001998 if (N1C && N1C->getAPIntValue() == 1)
Bill Wendling326411d2009-01-30 03:00:18 +00001999 return DAG.getNode(ISD::SRA, N->getDebugLoc(), N0.getValueType(), N0,
2000 DAG.getConstant(N0.getValueType().getSizeInBits() - 1,
Owen Anderson95771af2011-02-25 21:41:48 +00002001 getShiftAmountTy(N0.getValueType())));
Dan Gohman613e0d82007-07-03 14:03:57 +00002002 // fold (mulhs x, undef) -> 0
Dan Gohmand595b5f2007-07-10 14:20:37 +00002003 if (N0.getOpcode() == ISD::UNDEF || N1.getOpcode() == ISD::UNDEF)
Dan Gohman613e0d82007-07-03 14:03:57 +00002004 return DAG.getConstant(0, VT);
Dan Gohman7f321562007-06-25 16:23:39 +00002005
Chris Lattnerde1c3602010-12-13 08:39:01 +00002006 // If the type twice as wide is legal, transform the mulhs to a wider multiply
2007 // plus a shift.
2008 if (VT.isSimple() && !VT.isVector()) {
2009 MVT Simple = VT.getSimpleVT();
2010 unsigned SimpleSize = Simple.getSizeInBits();
2011 EVT NewVT = EVT::getIntegerVT(*DAG.getContext(), SimpleSize*2);
2012 if (TLI.isOperationLegal(ISD::MUL, NewVT)) {
2013 N0 = DAG.getNode(ISD::SIGN_EXTEND, DL, NewVT, N0);
2014 N1 = DAG.getNode(ISD::SIGN_EXTEND, DL, NewVT, N1);
2015 N1 = DAG.getNode(ISD::MUL, DL, NewVT, N0, N1);
Chris Lattner1a0fbe22010-12-15 05:51:39 +00002016 N1 = DAG.getNode(ISD::SRL, DL, NewVT, N1,
Owen Anderson95771af2011-02-25 21:41:48 +00002017 DAG.getConstant(SimpleSize, getShiftAmountTy(N1.getValueType())));
Chris Lattnerde1c3602010-12-13 08:39:01 +00002018 return DAG.getNode(ISD::TRUNCATE, DL, VT, N1);
2019 }
2020 }
Owen Anderson95771af2011-02-25 21:41:48 +00002021
Dan Gohman475871a2008-07-27 21:46:04 +00002022 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00002023}
2024
Dan Gohman475871a2008-07-27 21:46:04 +00002025SDValue DAGCombiner::visitMULHU(SDNode *N) {
2026 SDValue N0 = N->getOperand(0);
2027 SDValue N1 = N->getOperand(1);
Nate Begeman646d7e22005-09-02 21:18:40 +00002028 ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1);
Owen Andersone50ed302009-08-10 22:56:29 +00002029 EVT VT = N->getValueType(0);
Chris Lattnerde1c3602010-12-13 08:39:01 +00002030 DebugLoc DL = N->getDebugLoc();
Scott Michelfdc40a02009-02-17 22:15:04 +00002031
Nate Begeman1d4d4142005-09-01 00:19:25 +00002032 // fold (mulhu x, 0) -> 0
Nate Begeman646d7e22005-09-02 21:18:40 +00002033 if (N1C && N1C->isNullValue())
Nate Begeman83e75ec2005-09-06 04:43:02 +00002034 return N1;
Nate Begeman1d4d4142005-09-01 00:19:25 +00002035 // fold (mulhu x, 1) -> 0
Dan Gohman002e5d02008-03-13 22:13:53 +00002036 if (N1C && N1C->getAPIntValue() == 1)
Nate Begeman83e75ec2005-09-06 04:43:02 +00002037 return DAG.getConstant(0, N0.getValueType());
Dan Gohman613e0d82007-07-03 14:03:57 +00002038 // fold (mulhu x, undef) -> 0
Dan Gohmand595b5f2007-07-10 14:20:37 +00002039 if (N0.getOpcode() == ISD::UNDEF || N1.getOpcode() == ISD::UNDEF)
Dan Gohman613e0d82007-07-03 14:03:57 +00002040 return DAG.getConstant(0, VT);
Dan Gohman7f321562007-06-25 16:23:39 +00002041
Chris Lattnerde1c3602010-12-13 08:39:01 +00002042 // If the type twice as wide is legal, transform the mulhu to a wider multiply
2043 // plus a shift.
2044 if (VT.isSimple() && !VT.isVector()) {
2045 MVT Simple = VT.getSimpleVT();
2046 unsigned SimpleSize = Simple.getSizeInBits();
2047 EVT NewVT = EVT::getIntegerVT(*DAG.getContext(), SimpleSize*2);
2048 if (TLI.isOperationLegal(ISD::MUL, NewVT)) {
2049 N0 = DAG.getNode(ISD::ZERO_EXTEND, DL, NewVT, N0);
2050 N1 = DAG.getNode(ISD::ZERO_EXTEND, DL, NewVT, N1);
2051 N1 = DAG.getNode(ISD::MUL, DL, NewVT, N0, N1);
2052 N1 = DAG.getNode(ISD::SRL, DL, NewVT, N1,
Owen Anderson95771af2011-02-25 21:41:48 +00002053 DAG.getConstant(SimpleSize, getShiftAmountTy(N1.getValueType())));
Chris Lattnerde1c3602010-12-13 08:39:01 +00002054 return DAG.getNode(ISD::TRUNCATE, DL, VT, N1);
2055 }
2056 }
Owen Anderson95771af2011-02-25 21:41:48 +00002057
Dan Gohman475871a2008-07-27 21:46:04 +00002058 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00002059}
2060
Dan Gohman389079b2007-10-08 17:57:15 +00002061/// SimplifyNodeWithTwoResults - Perform optimizations common to nodes that
2062/// compute two values. LoOp and HiOp give the opcodes for the two computations
2063/// that are being performed. Return true if a simplification was made.
2064///
Scott Michelfdc40a02009-02-17 22:15:04 +00002065SDValue DAGCombiner::SimplifyNodeWithTwoResults(SDNode *N, unsigned LoOp,
Dan Gohman475871a2008-07-27 21:46:04 +00002066 unsigned HiOp) {
Dan Gohman389079b2007-10-08 17:57:15 +00002067 // If the high half is not needed, just compute the low half.
Evan Cheng44711942007-11-08 09:25:29 +00002068 bool HiExists = N->hasAnyUseOfValue(1);
2069 if (!HiExists &&
Duncan Sands25cf2272008-11-24 14:53:14 +00002070 (!LegalOperations ||
Dan Gohman389079b2007-10-08 17:57:15 +00002071 TLI.isOperationLegal(LoOp, N->getValueType(0)))) {
Bill Wendling826d1142009-01-30 03:08:40 +00002072 SDValue Res = DAG.getNode(LoOp, N->getDebugLoc(), N->getValueType(0),
2073 N->op_begin(), N->getNumOperands());
Chris Lattner5eee4272008-01-26 01:09:19 +00002074 return CombineTo(N, Res, Res);
Dan Gohman389079b2007-10-08 17:57:15 +00002075 }
2076
2077 // If the low half is not needed, just compute the high half.
Evan Cheng44711942007-11-08 09:25:29 +00002078 bool LoExists = N->hasAnyUseOfValue(0);
2079 if (!LoExists &&
Duncan Sands25cf2272008-11-24 14:53:14 +00002080 (!LegalOperations ||
Dan Gohman389079b2007-10-08 17:57:15 +00002081 TLI.isOperationLegal(HiOp, N->getValueType(1)))) {
Bill Wendling826d1142009-01-30 03:08:40 +00002082 SDValue Res = DAG.getNode(HiOp, N->getDebugLoc(), N->getValueType(1),
2083 N->op_begin(), N->getNumOperands());
Chris Lattner5eee4272008-01-26 01:09:19 +00002084 return CombineTo(N, Res, Res);
Dan Gohman389079b2007-10-08 17:57:15 +00002085 }
2086
Evan Cheng44711942007-11-08 09:25:29 +00002087 // If both halves are used, return as it is.
2088 if (LoExists && HiExists)
Dan Gohman475871a2008-07-27 21:46:04 +00002089 return SDValue();
Evan Cheng44711942007-11-08 09:25:29 +00002090
2091 // If the two computed results can be simplified separately, separate them.
Evan Cheng44711942007-11-08 09:25:29 +00002092 if (LoExists) {
Bill Wendling826d1142009-01-30 03:08:40 +00002093 SDValue Lo = DAG.getNode(LoOp, N->getDebugLoc(), N->getValueType(0),
2094 N->op_begin(), N->getNumOperands());
Gabor Greifba36cb52008-08-28 21:40:38 +00002095 AddToWorkList(Lo.getNode());
2096 SDValue LoOpt = combine(Lo.getNode());
2097 if (LoOpt.getNode() && LoOpt.getNode() != Lo.getNode() &&
Duncan Sands25cf2272008-11-24 14:53:14 +00002098 (!LegalOperations ||
Duncan Sandsd4b9c172008-06-13 19:07:40 +00002099 TLI.isOperationLegal(LoOpt.getOpcode(), LoOpt.getValueType())))
Chris Lattner5eee4272008-01-26 01:09:19 +00002100 return CombineTo(N, LoOpt, LoOpt);
Dan Gohman389079b2007-10-08 17:57:15 +00002101 }
2102
Evan Cheng44711942007-11-08 09:25:29 +00002103 if (HiExists) {
Bill Wendling826d1142009-01-30 03:08:40 +00002104 SDValue Hi = DAG.getNode(HiOp, N->getDebugLoc(), N->getValueType(1),
Duncan Sands25cf2272008-11-24 14:53:14 +00002105 N->op_begin(), N->getNumOperands());
Gabor Greifba36cb52008-08-28 21:40:38 +00002106 AddToWorkList(Hi.getNode());
2107 SDValue HiOpt = combine(Hi.getNode());
2108 if (HiOpt.getNode() && HiOpt != Hi &&
Duncan Sands25cf2272008-11-24 14:53:14 +00002109 (!LegalOperations ||
Duncan Sandsd4b9c172008-06-13 19:07:40 +00002110 TLI.isOperationLegal(HiOpt.getOpcode(), HiOpt.getValueType())))
Chris Lattner5eee4272008-01-26 01:09:19 +00002111 return CombineTo(N, HiOpt, HiOpt);
Evan Cheng44711942007-11-08 09:25:29 +00002112 }
Bill Wendling826d1142009-01-30 03:08:40 +00002113
Dan Gohman475871a2008-07-27 21:46:04 +00002114 return SDValue();
Dan Gohman389079b2007-10-08 17:57:15 +00002115}
2116
Dan Gohman475871a2008-07-27 21:46:04 +00002117SDValue DAGCombiner::visitSMUL_LOHI(SDNode *N) {
2118 SDValue Res = SimplifyNodeWithTwoResults(N, ISD::MUL, ISD::MULHS);
Gabor Greifba36cb52008-08-28 21:40:38 +00002119 if (Res.getNode()) return Res;
Dan Gohman389079b2007-10-08 17:57:15 +00002120
Chris Lattner33e77d32010-12-15 06:04:19 +00002121 EVT VT = N->getValueType(0);
2122 DebugLoc DL = N->getDebugLoc();
2123
2124 // If the type twice as wide is legal, transform the mulhu to a wider multiply
2125 // plus a shift.
2126 if (VT.isSimple() && !VT.isVector()) {
2127 MVT Simple = VT.getSimpleVT();
2128 unsigned SimpleSize = Simple.getSizeInBits();
2129 EVT NewVT = EVT::getIntegerVT(*DAG.getContext(), SimpleSize*2);
2130 if (TLI.isOperationLegal(ISD::MUL, NewVT)) {
2131 SDValue Lo = DAG.getNode(ISD::SIGN_EXTEND, DL, NewVT, N->getOperand(0));
2132 SDValue Hi = DAG.getNode(ISD::SIGN_EXTEND, DL, NewVT, N->getOperand(1));
2133 Lo = DAG.getNode(ISD::MUL, DL, NewVT, Lo, Hi);
2134 // Compute the high part as N1.
2135 Hi = DAG.getNode(ISD::SRL, DL, NewVT, Lo,
Owen Anderson95771af2011-02-25 21:41:48 +00002136 DAG.getConstant(SimpleSize, getShiftAmountTy(Lo.getValueType())));
Chris Lattner33e77d32010-12-15 06:04:19 +00002137 Hi = DAG.getNode(ISD::TRUNCATE, DL, VT, Hi);
2138 // Compute the low part as N0.
2139 Lo = DAG.getNode(ISD::TRUNCATE, DL, VT, Lo);
2140 return CombineTo(N, Lo, Hi);
2141 }
2142 }
Owen Anderson95771af2011-02-25 21:41:48 +00002143
Dan Gohman475871a2008-07-27 21:46:04 +00002144 return SDValue();
Dan Gohman389079b2007-10-08 17:57:15 +00002145}
2146
Dan Gohman475871a2008-07-27 21:46:04 +00002147SDValue DAGCombiner::visitUMUL_LOHI(SDNode *N) {
2148 SDValue Res = SimplifyNodeWithTwoResults(N, ISD::MUL, ISD::MULHU);
Gabor Greifba36cb52008-08-28 21:40:38 +00002149 if (Res.getNode()) return Res;
Dan Gohman389079b2007-10-08 17:57:15 +00002150
Chris Lattner33e77d32010-12-15 06:04:19 +00002151 EVT VT = N->getValueType(0);
2152 DebugLoc DL = N->getDebugLoc();
Owen Anderson95771af2011-02-25 21:41:48 +00002153
Chris Lattner33e77d32010-12-15 06:04:19 +00002154 // If the type twice as wide is legal, transform the mulhu to a wider multiply
2155 // plus a shift.
2156 if (VT.isSimple() && !VT.isVector()) {
2157 MVT Simple = VT.getSimpleVT();
2158 unsigned SimpleSize = Simple.getSizeInBits();
2159 EVT NewVT = EVT::getIntegerVT(*DAG.getContext(), SimpleSize*2);
2160 if (TLI.isOperationLegal(ISD::MUL, NewVT)) {
2161 SDValue Lo = DAG.getNode(ISD::ZERO_EXTEND, DL, NewVT, N->getOperand(0));
2162 SDValue Hi = DAG.getNode(ISD::ZERO_EXTEND, DL, NewVT, N->getOperand(1));
2163 Lo = DAG.getNode(ISD::MUL, DL, NewVT, Lo, Hi);
2164 // Compute the high part as N1.
2165 Hi = DAG.getNode(ISD::SRL, DL, NewVT, Lo,
Owen Anderson95771af2011-02-25 21:41:48 +00002166 DAG.getConstant(SimpleSize, getShiftAmountTy(Lo.getValueType())));
Chris Lattner33e77d32010-12-15 06:04:19 +00002167 Hi = DAG.getNode(ISD::TRUNCATE, DL, VT, Hi);
2168 // Compute the low part as N0.
2169 Lo = DAG.getNode(ISD::TRUNCATE, DL, VT, Lo);
2170 return CombineTo(N, Lo, Hi);
2171 }
2172 }
Owen Anderson95771af2011-02-25 21:41:48 +00002173
Dan Gohman475871a2008-07-27 21:46:04 +00002174 return SDValue();
Dan Gohman389079b2007-10-08 17:57:15 +00002175}
2176
Dan Gohman475871a2008-07-27 21:46:04 +00002177SDValue DAGCombiner::visitSDIVREM(SDNode *N) {
2178 SDValue Res = SimplifyNodeWithTwoResults(N, ISD::SDIV, ISD::SREM);
Gabor Greifba36cb52008-08-28 21:40:38 +00002179 if (Res.getNode()) return Res;
Scott Michelfdc40a02009-02-17 22:15:04 +00002180
Dan Gohman475871a2008-07-27 21:46:04 +00002181 return SDValue();
Dan Gohman389079b2007-10-08 17:57:15 +00002182}
2183
Dan Gohman475871a2008-07-27 21:46:04 +00002184SDValue DAGCombiner::visitUDIVREM(SDNode *N) {
2185 SDValue Res = SimplifyNodeWithTwoResults(N, ISD::UDIV, ISD::UREM);
Gabor Greifba36cb52008-08-28 21:40:38 +00002186 if (Res.getNode()) return Res;
Scott Michelfdc40a02009-02-17 22:15:04 +00002187
Dan Gohman475871a2008-07-27 21:46:04 +00002188 return SDValue();
Dan Gohman389079b2007-10-08 17:57:15 +00002189}
2190
Chris Lattner35e5c142006-05-05 05:51:50 +00002191/// SimplifyBinOpWithSameOpcodeHands - If this is a binary operator with
2192/// two operands of the same opcode, try to simplify it.
Dan Gohman475871a2008-07-27 21:46:04 +00002193SDValue DAGCombiner::SimplifyBinOpWithSameOpcodeHands(SDNode *N) {
2194 SDValue N0 = N->getOperand(0), N1 = N->getOperand(1);
Owen Andersone50ed302009-08-10 22:56:29 +00002195 EVT VT = N0.getValueType();
Chris Lattner35e5c142006-05-05 05:51:50 +00002196 assert(N0.getOpcode() == N1.getOpcode() && "Bad input!");
Scott Michelfdc40a02009-02-17 22:15:04 +00002197
Dan Gohmanff00a552010-01-14 03:08:49 +00002198 // Bail early if none of these transforms apply.
2199 if (N0.getNode()->getNumOperands() == 0) return SDValue();
2200
Chris Lattner540121f2006-05-05 06:31:05 +00002201 // For each of OP in AND/OR/XOR:
2202 // fold (OP (zext x), (zext y)) -> (zext (OP x, y))
2203 // fold (OP (sext x), (sext y)) -> (sext (OP x, y))
2204 // fold (OP (aext x), (aext y)) -> (aext (OP x, y))
Dan Gohman4e39e9d2010-06-24 14:30:44 +00002205 // fold (OP (trunc x), (trunc y)) -> (trunc (OP x, y)) (if trunc isn't free)
Nate Begeman93e0ed32009-12-03 07:11:29 +00002206 //
2207 // do not sink logical op inside of a vector extend, since it may combine
2208 // into a vsetcc.
Evan Chengd40d03e2010-01-06 19:38:29 +00002209 EVT Op0VT = N0.getOperand(0).getValueType();
2210 if ((N0.getOpcode() == ISD::ZERO_EXTEND ||
Dan Gohman97121ba2009-04-08 00:15:30 +00002211 N0.getOpcode() == ISD::SIGN_EXTEND ||
Evan Chenge5b51ac2010-04-17 06:13:15 +00002212 // Avoid infinite looping with PromoteIntBinOp.
2213 (N0.getOpcode() == ISD::ANY_EXTEND &&
2214 (!LegalTypes || TLI.isTypeDesirableForOp(N->getOpcode(), Op0VT))) ||
Dan Gohman4e39e9d2010-06-24 14:30:44 +00002215 (N0.getOpcode() == ISD::TRUNCATE &&
2216 (!TLI.isZExtFree(VT, Op0VT) ||
2217 !TLI.isTruncateFree(Op0VT, VT)) &&
2218 TLI.isTypeLegal(Op0VT))) &&
Nate Begeman93e0ed32009-12-03 07:11:29 +00002219 !VT.isVector() &&
Evan Chengd40d03e2010-01-06 19:38:29 +00002220 Op0VT == N1.getOperand(0).getValueType() &&
2221 (!LegalOperations || TLI.isOperationLegal(N->getOpcode(), Op0VT))) {
Bill Wendlingb74c8672009-01-30 19:25:47 +00002222 SDValue ORNode = DAG.getNode(N->getOpcode(), N0.getDebugLoc(),
2223 N0.getOperand(0).getValueType(),
2224 N0.getOperand(0), N1.getOperand(0));
Gabor Greifba36cb52008-08-28 21:40:38 +00002225 AddToWorkList(ORNode.getNode());
Bill Wendlingb74c8672009-01-30 19:25:47 +00002226 return DAG.getNode(N0.getOpcode(), N->getDebugLoc(), VT, ORNode);
Chris Lattner35e5c142006-05-05 05:51:50 +00002227 }
Scott Michelfdc40a02009-02-17 22:15:04 +00002228
Chris Lattnera3dc3f62006-05-05 06:10:43 +00002229 // For each of OP in SHL/SRL/SRA/AND...
2230 // fold (and (OP x, z), (OP y, z)) -> (OP (and x, y), z)
2231 // fold (or (OP x, z), (OP y, z)) -> (OP (or x, y), z)
2232 // fold (xor (OP x, z), (OP y, z)) -> (OP (xor x, y), z)
Chris Lattner35e5c142006-05-05 05:51:50 +00002233 if ((N0.getOpcode() == ISD::SHL || N0.getOpcode() == ISD::SRL ||
Chris Lattnera3dc3f62006-05-05 06:10:43 +00002234 N0.getOpcode() == ISD::SRA || N0.getOpcode() == ISD::AND) &&
Chris Lattner35e5c142006-05-05 05:51:50 +00002235 N0.getOperand(1) == N1.getOperand(1)) {
Bill Wendlingb74c8672009-01-30 19:25:47 +00002236 SDValue ORNode = DAG.getNode(N->getOpcode(), N0.getDebugLoc(),
2237 N0.getOperand(0).getValueType(),
2238 N0.getOperand(0), N1.getOperand(0));
Gabor Greifba36cb52008-08-28 21:40:38 +00002239 AddToWorkList(ORNode.getNode());
Bill Wendlingb74c8672009-01-30 19:25:47 +00002240 return DAG.getNode(N0.getOpcode(), N->getDebugLoc(), VT,
2241 ORNode, N0.getOperand(1));
Chris Lattner35e5c142006-05-05 05:51:50 +00002242 }
Scott Michelfdc40a02009-02-17 22:15:04 +00002243
Dan Gohman475871a2008-07-27 21:46:04 +00002244 return SDValue();
Chris Lattner35e5c142006-05-05 05:51:50 +00002245}
2246
Dan Gohman475871a2008-07-27 21:46:04 +00002247SDValue DAGCombiner::visitAND(SDNode *N) {
2248 SDValue N0 = N->getOperand(0);
2249 SDValue N1 = N->getOperand(1);
2250 SDValue LL, LR, RL, RR, CC0, CC1;
Nate Begeman646d7e22005-09-02 21:18:40 +00002251 ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0);
2252 ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1);
Owen Andersone50ed302009-08-10 22:56:29 +00002253 EVT VT = N1.getValueType();
Dan Gohman6900a392010-03-04 00:23:16 +00002254 unsigned BitWidth = VT.getScalarType().getSizeInBits();
Scott Michelfdc40a02009-02-17 22:15:04 +00002255
Dan Gohman7f321562007-06-25 16:23:39 +00002256 // fold vector ops
Duncan Sands83ec4b62008-06-06 12:08:01 +00002257 if (VT.isVector()) {
Dan Gohman475871a2008-07-27 21:46:04 +00002258 SDValue FoldedVOp = SimplifyVBinOp(N);
Gabor Greifba36cb52008-08-28 21:40:38 +00002259 if (FoldedVOp.getNode()) return FoldedVOp;
Dan Gohman05d92fe2007-07-13 20:03:40 +00002260 }
Scott Michelfdc40a02009-02-17 22:15:04 +00002261
Dan Gohman613e0d82007-07-03 14:03:57 +00002262 // fold (and x, undef) -> 0
Dan Gohmand595b5f2007-07-10 14:20:37 +00002263 if (N0.getOpcode() == ISD::UNDEF || N1.getOpcode() == ISD::UNDEF)
Dan Gohman613e0d82007-07-03 14:03:57 +00002264 return DAG.getConstant(0, VT);
Nate Begeman1d4d4142005-09-01 00:19:25 +00002265 // fold (and c1, c2) -> c1&c2
Nate Begeman646d7e22005-09-02 21:18:40 +00002266 if (N0C && N1C)
Bill Wendlingf3cbca22008-09-24 10:25:02 +00002267 return DAG.FoldConstantArithmetic(ISD::AND, VT, N0C, N1C);
Nate Begeman99801192005-09-07 23:25:52 +00002268 // canonicalize constant to RHS
Nate Begemana0e221d2005-10-18 00:28:13 +00002269 if (N0C && !N1C)
Bill Wendlingfc4b6772009-02-01 11:19:36 +00002270 return DAG.getNode(ISD::AND, N->getDebugLoc(), VT, N1, N0);
Nate Begeman1d4d4142005-09-01 00:19:25 +00002271 // fold (and x, -1) -> x
Nate Begeman646d7e22005-09-02 21:18:40 +00002272 if (N1C && N1C->isAllOnesValue())
Nate Begeman83e75ec2005-09-06 04:43:02 +00002273 return N0;
2274 // if (and x, c) is known to be zero, return 0
Dan Gohman475871a2008-07-27 21:46:04 +00002275 if (N1C && DAG.MaskedValueIsZero(SDValue(N, 0),
Dan Gohman2e68b6f2008-02-25 21:11:39 +00002276 APInt::getAllOnesValue(BitWidth)))
Nate Begeman83e75ec2005-09-06 04:43:02 +00002277 return DAG.getConstant(0, VT);
Nate Begemancd4d58c2006-02-03 06:46:56 +00002278 // reassociate and
Bill Wendling35247c32009-01-30 00:45:56 +00002279 SDValue RAND = ReassociateOps(ISD::AND, N->getDebugLoc(), N0, N1);
Gabor Greifba36cb52008-08-28 21:40:38 +00002280 if (RAND.getNode() != 0)
Nate Begemancd4d58c2006-02-03 06:46:56 +00002281 return RAND;
Bill Wendling7d9f2b92010-03-03 00:35:56 +00002282 // fold (and (or x, C), D) -> D if (C & D) == D
Nate Begeman5dc7e862005-11-02 18:42:59 +00002283 if (N1C && N0.getOpcode() == ISD::OR)
Nate Begeman1d4d4142005-09-01 00:19:25 +00002284 if (ConstantSDNode *ORI = dyn_cast<ConstantSDNode>(N0.getOperand(1)))
Dan Gohman002e5d02008-03-13 22:13:53 +00002285 if ((ORI->getAPIntValue() & N1C->getAPIntValue()) == N1C->getAPIntValue())
Nate Begeman83e75ec2005-09-06 04:43:02 +00002286 return N1;
Chris Lattner3603cd62006-02-02 07:17:31 +00002287 // fold (and (any_ext V), c) -> (zero_ext V) if 'and' only clears top bits.
2288 if (N1C && N0.getOpcode() == ISD::ANY_EXTEND) {
Dan Gohman475871a2008-07-27 21:46:04 +00002289 SDValue N0Op0 = N0.getOperand(0);
Dan Gohman2e68b6f2008-02-25 21:11:39 +00002290 APInt Mask = ~N1C->getAPIntValue();
Jay Foad40f8f622010-12-07 08:25:19 +00002291 Mask = Mask.trunc(N0Op0.getValueSizeInBits());
Dan Gohman2e68b6f2008-02-25 21:11:39 +00002292 if (DAG.MaskedValueIsZero(N0Op0, Mask)) {
Bill Wendling2627a882009-01-30 20:43:18 +00002293 SDValue Zext = DAG.getNode(ISD::ZERO_EXTEND, N->getDebugLoc(),
2294 N0.getValueType(), N0Op0);
Scott Michelfdc40a02009-02-17 22:15:04 +00002295
Chris Lattner1ec05d12006-03-01 21:47:21 +00002296 // Replace uses of the AND with uses of the Zero extend node.
2297 CombineTo(N, Zext);
Scott Michelfdc40a02009-02-17 22:15:04 +00002298
Chris Lattner3603cd62006-02-02 07:17:31 +00002299 // We actually want to replace all uses of the any_extend with the
2300 // zero_extend, to avoid duplicating things. This will later cause this
2301 // AND to be folded.
Gabor Greifba36cb52008-08-28 21:40:38 +00002302 CombineTo(N0.getNode(), Zext);
Dan Gohman475871a2008-07-27 21:46:04 +00002303 return SDValue(N, 0); // Return N so it doesn't get rechecked!
Chris Lattner3603cd62006-02-02 07:17:31 +00002304 }
2305 }
Nate Begeman39ee1ac2005-09-09 19:49:52 +00002306 // fold (and (setcc x), (setcc y)) -> (setcc (and x, y))
2307 if (isSetCCEquivalent(N0, LL, LR, CC0) && isSetCCEquivalent(N1, RL, RR, CC1)){
2308 ISD::CondCode Op0 = cast<CondCodeSDNode>(CC0)->get();
2309 ISD::CondCode Op1 = cast<CondCodeSDNode>(CC1)->get();
Scott Michelfdc40a02009-02-17 22:15:04 +00002310
Nate Begeman39ee1ac2005-09-09 19:49:52 +00002311 if (LR == RR && isa<ConstantSDNode>(LR) && Op0 == Op1 &&
Duncan Sands83ec4b62008-06-06 12:08:01 +00002312 LL.getValueType().isInteger()) {
Bill Wendling2627a882009-01-30 20:43:18 +00002313 // fold (and (seteq X, 0), (seteq Y, 0)) -> (seteq (or X, Y), 0)
Dan Gohman002e5d02008-03-13 22:13:53 +00002314 if (cast<ConstantSDNode>(LR)->isNullValue() && Op1 == ISD::SETEQ) {
Bill Wendling2627a882009-01-30 20:43:18 +00002315 SDValue ORNode = DAG.getNode(ISD::OR, N0.getDebugLoc(),
2316 LR.getValueType(), LL, RL);
Gabor Greifba36cb52008-08-28 21:40:38 +00002317 AddToWorkList(ORNode.getNode());
Bill Wendling2627a882009-01-30 20:43:18 +00002318 return DAG.getSetCC(N->getDebugLoc(), VT, ORNode, LR, Op1);
Nate Begeman39ee1ac2005-09-09 19:49:52 +00002319 }
Bill Wendling2627a882009-01-30 20:43:18 +00002320 // fold (and (seteq X, -1), (seteq Y, -1)) -> (seteq (and X, Y), -1)
Nate Begeman39ee1ac2005-09-09 19:49:52 +00002321 if (cast<ConstantSDNode>(LR)->isAllOnesValue() && Op1 == ISD::SETEQ) {
Bill Wendling2627a882009-01-30 20:43:18 +00002322 SDValue ANDNode = DAG.getNode(ISD::AND, N0.getDebugLoc(),
2323 LR.getValueType(), LL, RL);
Gabor Greifba36cb52008-08-28 21:40:38 +00002324 AddToWorkList(ANDNode.getNode());
Bill Wendling2627a882009-01-30 20:43:18 +00002325 return DAG.getSetCC(N->getDebugLoc(), VT, ANDNode, LR, Op1);
Nate Begeman39ee1ac2005-09-09 19:49:52 +00002326 }
Bill Wendling2627a882009-01-30 20:43:18 +00002327 // fold (and (setgt X, -1), (setgt Y, -1)) -> (setgt (or X, Y), -1)
Nate Begeman39ee1ac2005-09-09 19:49:52 +00002328 if (cast<ConstantSDNode>(LR)->isAllOnesValue() && Op1 == ISD::SETGT) {
Bill Wendling2627a882009-01-30 20:43:18 +00002329 SDValue ORNode = DAG.getNode(ISD::OR, N0.getDebugLoc(),
2330 LR.getValueType(), LL, RL);
Gabor Greifba36cb52008-08-28 21:40:38 +00002331 AddToWorkList(ORNode.getNode());
Bill Wendling2627a882009-01-30 20:43:18 +00002332 return DAG.getSetCC(N->getDebugLoc(), VT, ORNode, LR, Op1);
Nate Begeman39ee1ac2005-09-09 19:49:52 +00002333 }
2334 }
2335 // canonicalize equivalent to ll == rl
2336 if (LL == RR && LR == RL) {
2337 Op1 = ISD::getSetCCSwappedOperands(Op1);
2338 std::swap(RL, RR);
2339 }
2340 if (LL == RL && LR == RR) {
Duncan Sands83ec4b62008-06-06 12:08:01 +00002341 bool isInteger = LL.getValueType().isInteger();
Nate Begeman39ee1ac2005-09-09 19:49:52 +00002342 ISD::CondCode Result = ISD::getSetCCAndOperation(Op0, Op1, isInteger);
Chris Lattner6e1c6232008-10-28 07:11:07 +00002343 if (Result != ISD::SETCC_INVALID &&
Duncan Sands25cf2272008-11-24 14:53:14 +00002344 (!LegalOperations || TLI.isCondCodeLegal(Result, LL.getValueType())))
Bill Wendling2627a882009-01-30 20:43:18 +00002345 return DAG.getSetCC(N->getDebugLoc(), N0.getValueType(),
2346 LL, LR, Result);
Nate Begeman39ee1ac2005-09-09 19:49:52 +00002347 }
2348 }
Chris Lattner35e5c142006-05-05 05:51:50 +00002349
Bill Wendling2627a882009-01-30 20:43:18 +00002350 // Simplify: (and (op x...), (op y...)) -> (op (and x, y))
Chris Lattner35e5c142006-05-05 05:51:50 +00002351 if (N0.getOpcode() == N1.getOpcode()) {
Dan Gohman475871a2008-07-27 21:46:04 +00002352 SDValue Tmp = SimplifyBinOpWithSameOpcodeHands(N);
Gabor Greifba36cb52008-08-28 21:40:38 +00002353 if (Tmp.getNode()) return Tmp;
Nate Begeman39ee1ac2005-09-09 19:49:52 +00002354 }
Scott Michelfdc40a02009-02-17 22:15:04 +00002355
Nate Begemande996292006-02-03 22:24:05 +00002356 // fold (and (sign_extend_inreg x, i16 to i32), 1) -> (and x, 1)
2357 // fold (and (sra)) -> (and (srl)) when possible.
Duncan Sands83ec4b62008-06-06 12:08:01 +00002358 if (!VT.isVector() &&
Dan Gohman475871a2008-07-27 21:46:04 +00002359 SimplifyDemandedBits(SDValue(N, 0)))
2360 return SDValue(N, 0);
Evan Chengd40d03e2010-01-06 19:38:29 +00002361
Nate Begemanded49632005-10-13 03:11:28 +00002362 // fold (zext_inreg (extload x)) -> (zextload x)
Gabor Greifba36cb52008-08-28 21:40:38 +00002363 if (ISD::isEXTLoad(N0.getNode()) && ISD::isUNINDEXEDLoad(N0.getNode())) {
Evan Cheng466685d2006-10-09 20:57:25 +00002364 LoadSDNode *LN0 = cast<LoadSDNode>(N0);
Dan Gohman8a55ce42009-09-23 21:02:20 +00002365 EVT MemVT = LN0->getMemoryVT();
Nate Begemanbfd65a02005-10-13 18:34:58 +00002366 // If we zero all the possible extended bits, then we can turn this into
2367 // a zextload if we are running before legalize or the operation is legal.
Dan Gohman6900a392010-03-04 00:23:16 +00002368 unsigned BitWidth = N1.getValueType().getScalarType().getSizeInBits();
Dan Gohman2e68b6f2008-02-25 21:11:39 +00002369 if (DAG.MaskedValueIsZero(N1, APInt::getHighBitsSet(BitWidth,
Dan Gohman6900a392010-03-04 00:23:16 +00002370 BitWidth - MemVT.getScalarType().getSizeInBits())) &&
Duncan Sands25cf2272008-11-24 14:53:14 +00002371 ((!LegalOperations && !LN0->isVolatile()) ||
Dan Gohman8a55ce42009-09-23 21:02:20 +00002372 TLI.isLoadExtLegal(ISD::ZEXTLOAD, MemVT))) {
Stuart Hastingsa9011292011-02-16 16:23:55 +00002373 SDValue ExtLoad = DAG.getExtLoad(ISD::ZEXTLOAD, N0.getDebugLoc(), VT,
Bill Wendling2627a882009-01-30 20:43:18 +00002374 LN0->getChain(), LN0->getBasePtr(),
Chris Lattner3d6ccfb2010-09-21 17:04:51 +00002375 LN0->getPointerInfo(), MemVT,
David Greene1e559442010-02-15 17:00:31 +00002376 LN0->isVolatile(), LN0->isNonTemporal(),
2377 LN0->getAlignment());
Chris Lattner5750df92006-03-01 04:03:14 +00002378 AddToWorkList(N);
Gabor Greifba36cb52008-08-28 21:40:38 +00002379 CombineTo(N0.getNode(), ExtLoad, ExtLoad.getValue(1));
Dan Gohman475871a2008-07-27 21:46:04 +00002380 return SDValue(N, 0); // Return N so it doesn't get rechecked!
Nate Begemanded49632005-10-13 03:11:28 +00002381 }
2382 }
2383 // fold (zext_inreg (sextload x)) -> (zextload x) iff load has one use
Gabor Greifba36cb52008-08-28 21:40:38 +00002384 if (ISD::isSEXTLoad(N0.getNode()) && ISD::isUNINDEXEDLoad(N0.getNode()) &&
Evan Cheng83060c52007-03-07 08:07:03 +00002385 N0.hasOneUse()) {
Evan Cheng466685d2006-10-09 20:57:25 +00002386 LoadSDNode *LN0 = cast<LoadSDNode>(N0);
Dan Gohman8a55ce42009-09-23 21:02:20 +00002387 EVT MemVT = LN0->getMemoryVT();
Nate Begemanbfd65a02005-10-13 18:34:58 +00002388 // If we zero all the possible extended bits, then we can turn this into
2389 // a zextload if we are running before legalize or the operation is legal.
Dan Gohman6900a392010-03-04 00:23:16 +00002390 unsigned BitWidth = N1.getValueType().getScalarType().getSizeInBits();
Dan Gohman2e68b6f2008-02-25 21:11:39 +00002391 if (DAG.MaskedValueIsZero(N1, APInt::getHighBitsSet(BitWidth,
Dan Gohman6900a392010-03-04 00:23:16 +00002392 BitWidth - MemVT.getScalarType().getSizeInBits())) &&
Duncan Sands25cf2272008-11-24 14:53:14 +00002393 ((!LegalOperations && !LN0->isVolatile()) ||
Dan Gohman8a55ce42009-09-23 21:02:20 +00002394 TLI.isLoadExtLegal(ISD::ZEXTLOAD, MemVT))) {
Stuart Hastingsa9011292011-02-16 16:23:55 +00002395 SDValue ExtLoad = DAG.getExtLoad(ISD::ZEXTLOAD, N0.getDebugLoc(), VT,
Bill Wendling2627a882009-01-30 20:43:18 +00002396 LN0->getChain(),
Chris Lattner3d6ccfb2010-09-21 17:04:51 +00002397 LN0->getBasePtr(), LN0->getPointerInfo(),
2398 MemVT,
David Greene1e559442010-02-15 17:00:31 +00002399 LN0->isVolatile(), LN0->isNonTemporal(),
2400 LN0->getAlignment());
Chris Lattner5750df92006-03-01 04:03:14 +00002401 AddToWorkList(N);
Gabor Greifba36cb52008-08-28 21:40:38 +00002402 CombineTo(N0.getNode(), ExtLoad, ExtLoad.getValue(1));
Dan Gohman475871a2008-07-27 21:46:04 +00002403 return SDValue(N, 0); // Return N so it doesn't get rechecked!
Nate Begemanded49632005-10-13 03:11:28 +00002404 }
2405 }
Scott Michelfdc40a02009-02-17 22:15:04 +00002406
Chris Lattner35a9f5a2006-02-28 06:49:37 +00002407 // fold (and (load x), 255) -> (zextload x, i8)
2408 // fold (and (extload x, i16), 255) -> (zextload x, i8)
Evan Chengd40d03e2010-01-06 19:38:29 +00002409 // fold (and (any_ext (extload x, i16)), 255) -> (zextload x, i8)
2410 if (N1C && (N0.getOpcode() == ISD::LOAD ||
2411 (N0.getOpcode() == ISD::ANY_EXTEND &&
2412 N0.getOperand(0).getOpcode() == ISD::LOAD))) {
2413 bool HasAnyExt = N0.getOpcode() == ISD::ANY_EXTEND;
2414 LoadSDNode *LN0 = HasAnyExt
2415 ? cast<LoadSDNode>(N0.getOperand(0))
2416 : cast<LoadSDNode>(N0);
Evan Cheng466685d2006-10-09 20:57:25 +00002417 if (LN0->getExtensionType() != ISD::SEXTLOAD &&
Chris Lattnerbd1fccf2010-01-07 21:59:23 +00002418 LN0->isUnindexed() && N0.hasOneUse() && LN0->hasOneUse()) {
Duncan Sands8eab8a22008-06-09 11:32:28 +00002419 uint32_t ActiveBits = N1C->getAPIntValue().getActiveBits();
Evan Chengd40d03e2010-01-06 19:38:29 +00002420 if (ActiveBits > 0 && APIntOps::isMask(ActiveBits, N1C->getAPIntValue())){
2421 EVT ExtVT = EVT::getIntegerVT(*DAG.getContext(), ActiveBits);
2422 EVT LoadedVT = LN0->getMemoryVT();
Duncan Sands8eab8a22008-06-09 11:32:28 +00002423
Evan Chengd40d03e2010-01-06 19:38:29 +00002424 if (ExtVT == LoadedVT &&
2425 (!LegalOperations || TLI.isLoadExtLegal(ISD::ZEXTLOAD, ExtVT))) {
Chris Lattneref7634c2010-01-07 21:53:27 +00002426 EVT LoadResultTy = HasAnyExt ? LN0->getValueType(0) : VT;
Wesley Peckbf17cfa2010-11-23 03:31:01 +00002427
2428 SDValue NewLoad =
Stuart Hastingsa9011292011-02-16 16:23:55 +00002429 DAG.getExtLoad(ISD::ZEXTLOAD, LN0->getDebugLoc(), LoadResultTy,
Chris Lattneref7634c2010-01-07 21:53:27 +00002430 LN0->getChain(), LN0->getBasePtr(),
Chris Lattner3d6ccfb2010-09-21 17:04:51 +00002431 LN0->getPointerInfo(),
David Greene1e559442010-02-15 17:00:31 +00002432 ExtVT, LN0->isVolatile(), LN0->isNonTemporal(),
2433 LN0->getAlignment());
Chris Lattneref7634c2010-01-07 21:53:27 +00002434 AddToWorkList(N);
2435 CombineTo(LN0, NewLoad, NewLoad.getValue(1));
2436 return SDValue(N, 0); // Return N so it doesn't get rechecked!
2437 }
Wesley Peckbf17cfa2010-11-23 03:31:01 +00002438
Chris Lattneref7634c2010-01-07 21:53:27 +00002439 // Do not change the width of a volatile load.
2440 // Do not generate loads of non-round integer types since these can
2441 // be expensive (and would be wrong if the type is not byte sized).
2442 if (!LN0->isVolatile() && LoadedVT.bitsGT(ExtVT) && ExtVT.isRound() &&
2443 (!LegalOperations || TLI.isLoadExtLegal(ISD::ZEXTLOAD, ExtVT))) {
2444 EVT PtrType = LN0->getOperand(1).getValueType();
Bill Wendling2627a882009-01-30 20:43:18 +00002445
Chris Lattneref7634c2010-01-07 21:53:27 +00002446 unsigned Alignment = LN0->getAlignment();
2447 SDValue NewPtr = LN0->getBasePtr();
2448
2449 // For big endian targets, we need to add an offset to the pointer
2450 // to load the correct bytes. For little endian systems, we merely
2451 // need to read fewer bytes from the same pointer.
2452 if (TLI.isBigEndian()) {
Evan Chengd40d03e2010-01-06 19:38:29 +00002453 unsigned LVTStoreBytes = LoadedVT.getStoreSize();
2454 unsigned EVTStoreBytes = ExtVT.getStoreSize();
2455 unsigned PtrOff = LVTStoreBytes - EVTStoreBytes;
Chris Lattneref7634c2010-01-07 21:53:27 +00002456 NewPtr = DAG.getNode(ISD::ADD, LN0->getDebugLoc(), PtrType,
2457 NewPtr, DAG.getConstant(PtrOff, PtrType));
2458 Alignment = MinAlign(Alignment, PtrOff);
Evan Chengd40d03e2010-01-06 19:38:29 +00002459 }
Chris Lattneref7634c2010-01-07 21:53:27 +00002460
2461 AddToWorkList(NewPtr.getNode());
Wesley Peckbf17cfa2010-11-23 03:31:01 +00002462
Chris Lattneref7634c2010-01-07 21:53:27 +00002463 EVT LoadResultTy = HasAnyExt ? LN0->getValueType(0) : VT;
2464 SDValue Load =
Stuart Hastingsa9011292011-02-16 16:23:55 +00002465 DAG.getExtLoad(ISD::ZEXTLOAD, LN0->getDebugLoc(), LoadResultTy,
Chris Lattneref7634c2010-01-07 21:53:27 +00002466 LN0->getChain(), NewPtr,
Chris Lattner3d6ccfb2010-09-21 17:04:51 +00002467 LN0->getPointerInfo(),
David Greene1e559442010-02-15 17:00:31 +00002468 ExtVT, LN0->isVolatile(), LN0->isNonTemporal(),
2469 Alignment);
Chris Lattneref7634c2010-01-07 21:53:27 +00002470 AddToWorkList(N);
2471 CombineTo(LN0, Load, Load.getValue(1));
2472 return SDValue(N, 0); // Return N so it doesn't get rechecked!
Duncan Sandsdc846502007-10-28 12:59:45 +00002473 }
Evan Cheng466685d2006-10-09 20:57:25 +00002474 }
Chris Lattner15045b62006-02-28 06:35:35 +00002475 }
2476 }
Scott Michelfdc40a02009-02-17 22:15:04 +00002477
Evan Chengb3a3d5e2010-04-28 07:10:39 +00002478 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00002479}
2480
Dan Gohman475871a2008-07-27 21:46:04 +00002481SDValue DAGCombiner::visitOR(SDNode *N) {
2482 SDValue N0 = N->getOperand(0);
2483 SDValue N1 = N->getOperand(1);
2484 SDValue LL, LR, RL, RR, CC0, CC1;
Nate Begeman646d7e22005-09-02 21:18:40 +00002485 ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0);
2486 ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1);
Owen Andersone50ed302009-08-10 22:56:29 +00002487 EVT VT = N1.getValueType();
Scott Michelfdc40a02009-02-17 22:15:04 +00002488
Dan Gohman7f321562007-06-25 16:23:39 +00002489 // fold vector ops
Duncan Sands83ec4b62008-06-06 12:08:01 +00002490 if (VT.isVector()) {
Dan Gohman475871a2008-07-27 21:46:04 +00002491 SDValue FoldedVOp = SimplifyVBinOp(N);
Gabor Greifba36cb52008-08-28 21:40:38 +00002492 if (FoldedVOp.getNode()) return FoldedVOp;
Dan Gohman05d92fe2007-07-13 20:03:40 +00002493 }
Scott Michelfdc40a02009-02-17 22:15:04 +00002494
Dan Gohman613e0d82007-07-03 14:03:57 +00002495 // fold (or x, undef) -> -1
Bob Wilson86749492010-06-28 23:40:25 +00002496 if (!LegalOperations &&
2497 (N0.getOpcode() == ISD::UNDEF || N1.getOpcode() == ISD::UNDEF)) {
Nate Begeman93e0ed32009-12-03 07:11:29 +00002498 EVT EltVT = VT.isVector() ? VT.getVectorElementType() : VT;
2499 return DAG.getConstant(APInt::getAllOnesValue(EltVT.getSizeInBits()), VT);
2500 }
Nate Begeman1d4d4142005-09-01 00:19:25 +00002501 // fold (or c1, c2) -> c1|c2
Nate Begeman646d7e22005-09-02 21:18:40 +00002502 if (N0C && N1C)
Bill Wendlingf3cbca22008-09-24 10:25:02 +00002503 return DAG.FoldConstantArithmetic(ISD::OR, VT, N0C, N1C);
Nate Begeman99801192005-09-07 23:25:52 +00002504 // canonicalize constant to RHS
Nate Begemana0e221d2005-10-18 00:28:13 +00002505 if (N0C && !N1C)
Bill Wendling09025642009-01-30 20:59:34 +00002506 return DAG.getNode(ISD::OR, N->getDebugLoc(), VT, N1, N0);
Nate Begeman1d4d4142005-09-01 00:19:25 +00002507 // fold (or x, 0) -> x
Nate Begeman646d7e22005-09-02 21:18:40 +00002508 if (N1C && N1C->isNullValue())
Nate Begeman83e75ec2005-09-06 04:43:02 +00002509 return N0;
Nate Begeman1d4d4142005-09-01 00:19:25 +00002510 // fold (or x, -1) -> -1
Nate Begeman646d7e22005-09-02 21:18:40 +00002511 if (N1C && N1C->isAllOnesValue())
Nate Begeman83e75ec2005-09-06 04:43:02 +00002512 return N1;
2513 // fold (or x, c) -> c iff (x & ~c) == 0
Dan Gohman2e68b6f2008-02-25 21:11:39 +00002514 if (N1C && DAG.MaskedValueIsZero(N0, ~N1C->getAPIntValue()))
Nate Begeman83e75ec2005-09-06 04:43:02 +00002515 return N1;
Nate Begemancd4d58c2006-02-03 06:46:56 +00002516 // reassociate or
Bill Wendling35247c32009-01-30 00:45:56 +00002517 SDValue ROR = ReassociateOps(ISD::OR, N->getDebugLoc(), N0, N1);
Gabor Greifba36cb52008-08-28 21:40:38 +00002518 if (ROR.getNode() != 0)
Nate Begemancd4d58c2006-02-03 06:46:56 +00002519 return ROR;
2520 // Canonicalize (or (and X, c1), c2) -> (and (or X, c2), c1|c2)
Bill Wendling7d9f2b92010-03-03 00:35:56 +00002521 // iff (c1 & c2) == 0.
Gabor Greifba36cb52008-08-28 21:40:38 +00002522 if (N1C && N0.getOpcode() == ISD::AND && N0.getNode()->hasOneUse() &&
Chris Lattner731d3482005-10-27 05:06:38 +00002523 isa<ConstantSDNode>(N0.getOperand(1))) {
Chris Lattner731d3482005-10-27 05:06:38 +00002524 ConstantSDNode *C1 = cast<ConstantSDNode>(N0.getOperand(1));
Bill Wendling32f9eb22010-03-03 01:58:01 +00002525 if ((C1->getAPIntValue() & N1C->getAPIntValue()) != 0)
Bill Wendling7d9f2b92010-03-03 00:35:56 +00002526 return DAG.getNode(ISD::AND, N->getDebugLoc(), VT,
2527 DAG.getNode(ISD::OR, N0.getDebugLoc(), VT,
2528 N0.getOperand(0), N1),
2529 DAG.FoldConstantArithmetic(ISD::OR, VT, N1C, C1));
Nate Begeman223df222005-09-08 20:18:10 +00002530 }
Nate Begeman39ee1ac2005-09-09 19:49:52 +00002531 // fold (or (setcc x), (setcc y)) -> (setcc (or x, y))
2532 if (isSetCCEquivalent(N0, LL, LR, CC0) && isSetCCEquivalent(N1, RL, RR, CC1)){
2533 ISD::CondCode Op0 = cast<CondCodeSDNode>(CC0)->get();
2534 ISD::CondCode Op1 = cast<CondCodeSDNode>(CC1)->get();
Scott Michelfdc40a02009-02-17 22:15:04 +00002535
Nate Begeman39ee1ac2005-09-09 19:49:52 +00002536 if (LR == RR && isa<ConstantSDNode>(LR) && Op0 == Op1 &&
Duncan Sands83ec4b62008-06-06 12:08:01 +00002537 LL.getValueType().isInteger()) {
Bill Wendling09025642009-01-30 20:59:34 +00002538 // fold (or (setne X, 0), (setne Y, 0)) -> (setne (or X, Y), 0)
2539 // fold (or (setlt X, 0), (setlt Y, 0)) -> (setne (or X, Y), 0)
Scott Michelfdc40a02009-02-17 22:15:04 +00002540 if (cast<ConstantSDNode>(LR)->isNullValue() &&
Nate Begeman39ee1ac2005-09-09 19:49:52 +00002541 (Op1 == ISD::SETNE || Op1 == ISD::SETLT)) {
Bill Wendling09025642009-01-30 20:59:34 +00002542 SDValue ORNode = DAG.getNode(ISD::OR, LR.getDebugLoc(),
2543 LR.getValueType(), LL, RL);
Gabor Greifba36cb52008-08-28 21:40:38 +00002544 AddToWorkList(ORNode.getNode());
Bill Wendling09025642009-01-30 20:59:34 +00002545 return DAG.getSetCC(N->getDebugLoc(), VT, ORNode, LR, Op1);
Nate Begeman39ee1ac2005-09-09 19:49:52 +00002546 }
Bill Wendling09025642009-01-30 20:59:34 +00002547 // fold (or (setne X, -1), (setne Y, -1)) -> (setne (and X, Y), -1)
2548 // fold (or (setgt X, -1), (setgt Y -1)) -> (setgt (and X, Y), -1)
Scott Michelfdc40a02009-02-17 22:15:04 +00002549 if (cast<ConstantSDNode>(LR)->isAllOnesValue() &&
Nate Begeman39ee1ac2005-09-09 19:49:52 +00002550 (Op1 == ISD::SETNE || Op1 == ISD::SETGT)) {
Bill Wendling09025642009-01-30 20:59:34 +00002551 SDValue ANDNode = DAG.getNode(ISD::AND, LR.getDebugLoc(),
2552 LR.getValueType(), LL, RL);
Gabor Greifba36cb52008-08-28 21:40:38 +00002553 AddToWorkList(ANDNode.getNode());
Bill Wendling09025642009-01-30 20:59:34 +00002554 return DAG.getSetCC(N->getDebugLoc(), VT, ANDNode, LR, Op1);
Nate Begeman39ee1ac2005-09-09 19:49:52 +00002555 }
2556 }
2557 // canonicalize equivalent to ll == rl
2558 if (LL == RR && LR == RL) {
2559 Op1 = ISD::getSetCCSwappedOperands(Op1);
2560 std::swap(RL, RR);
2561 }
2562 if (LL == RL && LR == RR) {
Duncan Sands83ec4b62008-06-06 12:08:01 +00002563 bool isInteger = LL.getValueType().isInteger();
Nate Begeman39ee1ac2005-09-09 19:49:52 +00002564 ISD::CondCode Result = ISD::getSetCCOrOperation(Op0, Op1, isInteger);
Chris Lattner6e1c6232008-10-28 07:11:07 +00002565 if (Result != ISD::SETCC_INVALID &&
Duncan Sands25cf2272008-11-24 14:53:14 +00002566 (!LegalOperations || TLI.isCondCodeLegal(Result, LL.getValueType())))
Bill Wendling09025642009-01-30 20:59:34 +00002567 return DAG.getSetCC(N->getDebugLoc(), N0.getValueType(),
2568 LL, LR, Result);
Nate Begeman39ee1ac2005-09-09 19:49:52 +00002569 }
2570 }
Scott Michelfdc40a02009-02-17 22:15:04 +00002571
Bill Wendling09025642009-01-30 20:59:34 +00002572 // Simplify: (or (op x...), (op y...)) -> (op (or x, y))
Chris Lattner35e5c142006-05-05 05:51:50 +00002573 if (N0.getOpcode() == N1.getOpcode()) {
Dan Gohman475871a2008-07-27 21:46:04 +00002574 SDValue Tmp = SimplifyBinOpWithSameOpcodeHands(N);
Gabor Greifba36cb52008-08-28 21:40:38 +00002575 if (Tmp.getNode()) return Tmp;
Nate Begeman39ee1ac2005-09-09 19:49:52 +00002576 }
Scott Michelfdc40a02009-02-17 22:15:04 +00002577
Bill Wendling09025642009-01-30 20:59:34 +00002578 // (or (and X, C1), (and Y, C2)) -> (and (or X, Y), C3) if possible.
Chris Lattner1ec72732006-09-14 21:11:37 +00002579 if (N0.getOpcode() == ISD::AND &&
2580 N1.getOpcode() == ISD::AND &&
2581 N0.getOperand(1).getOpcode() == ISD::Constant &&
2582 N1.getOperand(1).getOpcode() == ISD::Constant &&
2583 // Don't increase # computations.
Gabor Greifba36cb52008-08-28 21:40:38 +00002584 (N0.getNode()->hasOneUse() || N1.getNode()->hasOneUse())) {
Chris Lattner1ec72732006-09-14 21:11:37 +00002585 // We can only do this xform if we know that bits from X that are set in C2
2586 // but not in C1 are already zero. Likewise for Y.
Dan Gohman2e68b6f2008-02-25 21:11:39 +00002587 const APInt &LHSMask =
2588 cast<ConstantSDNode>(N0.getOperand(1))->getAPIntValue();
2589 const APInt &RHSMask =
2590 cast<ConstantSDNode>(N1.getOperand(1))->getAPIntValue();
Scott Michelfdc40a02009-02-17 22:15:04 +00002591
Dan Gohmanea859be2007-06-22 14:59:07 +00002592 if (DAG.MaskedValueIsZero(N0.getOperand(0), RHSMask&~LHSMask) &&
2593 DAG.MaskedValueIsZero(N1.getOperand(0), LHSMask&~RHSMask)) {
Bill Wendling09025642009-01-30 20:59:34 +00002594 SDValue X = DAG.getNode(ISD::OR, N0.getDebugLoc(), VT,
2595 N0.getOperand(0), N1.getOperand(0));
2596 return DAG.getNode(ISD::AND, N->getDebugLoc(), VT, X,
2597 DAG.getConstant(LHSMask | RHSMask, VT));
Chris Lattner1ec72732006-09-14 21:11:37 +00002598 }
2599 }
Scott Michelfdc40a02009-02-17 22:15:04 +00002600
Chris Lattner516b9622006-09-14 20:50:57 +00002601 // See if this is some rotate idiom.
Bill Wendling317bd702009-01-30 21:14:50 +00002602 if (SDNode *Rot = MatchRotate(N0, N1, N->getDebugLoc()))
Dan Gohman475871a2008-07-27 21:46:04 +00002603 return SDValue(Rot, 0);
Chris Lattner35e5c142006-05-05 05:51:50 +00002604
Dan Gohman4e39e9d2010-06-24 14:30:44 +00002605 // Simplify the operands using demanded-bits information.
2606 if (!VT.isVector() &&
2607 SimplifyDemandedBits(SDValue(N, 0)))
2608 return SDValue(N, 0);
2609
Evan Chengb3a3d5e2010-04-28 07:10:39 +00002610 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00002611}
2612
Chris Lattner516b9622006-09-14 20:50:57 +00002613/// MatchRotateHalf - Match "(X shl/srl V1) & V2" where V2 may not be present.
Dan Gohman475871a2008-07-27 21:46:04 +00002614static bool MatchRotateHalf(SDValue Op, SDValue &Shift, SDValue &Mask) {
Chris Lattner516b9622006-09-14 20:50:57 +00002615 if (Op.getOpcode() == ISD::AND) {
Reid Spencer3ed469c2006-11-02 20:25:50 +00002616 if (isa<ConstantSDNode>(Op.getOperand(1))) {
Chris Lattner516b9622006-09-14 20:50:57 +00002617 Mask = Op.getOperand(1);
2618 Op = Op.getOperand(0);
2619 } else {
2620 return false;
2621 }
2622 }
Scott Michelfdc40a02009-02-17 22:15:04 +00002623
Chris Lattner516b9622006-09-14 20:50:57 +00002624 if (Op.getOpcode() == ISD::SRL || Op.getOpcode() == ISD::SHL) {
2625 Shift = Op;
2626 return true;
2627 }
Bill Wendling09025642009-01-30 20:59:34 +00002628
Scott Michelfdc40a02009-02-17 22:15:04 +00002629 return false;
Chris Lattner516b9622006-09-14 20:50:57 +00002630}
2631
Chris Lattner516b9622006-09-14 20:50:57 +00002632// MatchRotate - Handle an 'or' of two operands. If this is one of the many
2633// idioms for rotate, and if the target supports rotation instructions, generate
2634// a rot[lr].
Bill Wendling317bd702009-01-30 21:14:50 +00002635SDNode *DAGCombiner::MatchRotate(SDValue LHS, SDValue RHS, DebugLoc DL) {
Duncan Sandsd4b9c172008-06-13 19:07:40 +00002636 // Must be a legal type. Expanded 'n promoted things won't work with rotates.
Owen Andersone50ed302009-08-10 22:56:29 +00002637 EVT VT = LHS.getValueType();
Chris Lattner516b9622006-09-14 20:50:57 +00002638 if (!TLI.isTypeLegal(VT)) return 0;
2639
2640 // The target must have at least one rotate flavor.
Dan Gohmanf560ffa2009-01-28 17:46:25 +00002641 bool HasROTL = TLI.isOperationLegalOrCustom(ISD::ROTL, VT);
2642 bool HasROTR = TLI.isOperationLegalOrCustom(ISD::ROTR, VT);
Chris Lattner516b9622006-09-14 20:50:57 +00002643 if (!HasROTL && !HasROTR) return 0;
Duncan Sandsd4b9c172008-06-13 19:07:40 +00002644
Chris Lattner516b9622006-09-14 20:50:57 +00002645 // Match "(X shl/srl V1) & V2" where V2 may not be present.
Dan Gohman475871a2008-07-27 21:46:04 +00002646 SDValue LHSShift; // The shift.
2647 SDValue LHSMask; // AND value if any.
Chris Lattner516b9622006-09-14 20:50:57 +00002648 if (!MatchRotateHalf(LHS, LHSShift, LHSMask))
2649 return 0; // Not part of a rotate.
2650
Dan Gohman475871a2008-07-27 21:46:04 +00002651 SDValue RHSShift; // The shift.
2652 SDValue RHSMask; // AND value if any.
Chris Lattner516b9622006-09-14 20:50:57 +00002653 if (!MatchRotateHalf(RHS, RHSShift, RHSMask))
2654 return 0; // Not part of a rotate.
Scott Michelfdc40a02009-02-17 22:15:04 +00002655
Chris Lattner516b9622006-09-14 20:50:57 +00002656 if (LHSShift.getOperand(0) != RHSShift.getOperand(0))
2657 return 0; // Not shifting the same value.
2658
2659 if (LHSShift.getOpcode() == RHSShift.getOpcode())
2660 return 0; // Shifts must disagree.
Scott Michelfdc40a02009-02-17 22:15:04 +00002661
Chris Lattner516b9622006-09-14 20:50:57 +00002662 // Canonicalize shl to left side in a shl/srl pair.
2663 if (RHSShift.getOpcode() == ISD::SHL) {
2664 std::swap(LHS, RHS);
2665 std::swap(LHSShift, RHSShift);
2666 std::swap(LHSMask , RHSMask );
2667 }
2668
Duncan Sands83ec4b62008-06-06 12:08:01 +00002669 unsigned OpSizeInBits = VT.getSizeInBits();
Dan Gohman475871a2008-07-27 21:46:04 +00002670 SDValue LHSShiftArg = LHSShift.getOperand(0);
2671 SDValue LHSShiftAmt = LHSShift.getOperand(1);
2672 SDValue RHSShiftAmt = RHSShift.getOperand(1);
Chris Lattner516b9622006-09-14 20:50:57 +00002673
2674 // fold (or (shl x, C1), (srl x, C2)) -> (rotl x, C1)
2675 // fold (or (shl x, C1), (srl x, C2)) -> (rotr x, C2)
Scott Michelc9dc1142007-04-02 21:36:32 +00002676 if (LHSShiftAmt.getOpcode() == ISD::Constant &&
2677 RHSShiftAmt.getOpcode() == ISD::Constant) {
Dan Gohmanf5aeb1a2008-09-12 16:56:44 +00002678 uint64_t LShVal = cast<ConstantSDNode>(LHSShiftAmt)->getZExtValue();
2679 uint64_t RShVal = cast<ConstantSDNode>(RHSShiftAmt)->getZExtValue();
Chris Lattner516b9622006-09-14 20:50:57 +00002680 if ((LShVal + RShVal) != OpSizeInBits)
2681 return 0;
2682
Dan Gohman475871a2008-07-27 21:46:04 +00002683 SDValue Rot;
Chris Lattner516b9622006-09-14 20:50:57 +00002684 if (HasROTL)
Bill Wendling317bd702009-01-30 21:14:50 +00002685 Rot = DAG.getNode(ISD::ROTL, DL, VT, LHSShiftArg, LHSShiftAmt);
Chris Lattner516b9622006-09-14 20:50:57 +00002686 else
Bill Wendling317bd702009-01-30 21:14:50 +00002687 Rot = DAG.getNode(ISD::ROTR, DL, VT, LHSShiftArg, RHSShiftAmt);
Scott Michelfdc40a02009-02-17 22:15:04 +00002688
Chris Lattner516b9622006-09-14 20:50:57 +00002689 // If there is an AND of either shifted operand, apply it to the result.
Gabor Greifba36cb52008-08-28 21:40:38 +00002690 if (LHSMask.getNode() || RHSMask.getNode()) {
Dan Gohman220a8232008-03-03 23:51:38 +00002691 APInt Mask = APInt::getAllOnesValue(OpSizeInBits);
Scott Michelfdc40a02009-02-17 22:15:04 +00002692
Gabor Greifba36cb52008-08-28 21:40:38 +00002693 if (LHSMask.getNode()) {
Dan Gohman220a8232008-03-03 23:51:38 +00002694 APInt RHSBits = APInt::getLowBitsSet(OpSizeInBits, LShVal);
2695 Mask &= cast<ConstantSDNode>(LHSMask)->getAPIntValue() | RHSBits;
Chris Lattner516b9622006-09-14 20:50:57 +00002696 }
Gabor Greifba36cb52008-08-28 21:40:38 +00002697 if (RHSMask.getNode()) {
Dan Gohman220a8232008-03-03 23:51:38 +00002698 APInt LHSBits = APInt::getHighBitsSet(OpSizeInBits, RShVal);
2699 Mask &= cast<ConstantSDNode>(RHSMask)->getAPIntValue() | LHSBits;
Chris Lattner516b9622006-09-14 20:50:57 +00002700 }
Scott Michelfdc40a02009-02-17 22:15:04 +00002701
Bill Wendling317bd702009-01-30 21:14:50 +00002702 Rot = DAG.getNode(ISD::AND, DL, VT, Rot, DAG.getConstant(Mask, VT));
Chris Lattner516b9622006-09-14 20:50:57 +00002703 }
Scott Michelfdc40a02009-02-17 22:15:04 +00002704
Gabor Greifba36cb52008-08-28 21:40:38 +00002705 return Rot.getNode();
Chris Lattner516b9622006-09-14 20:50:57 +00002706 }
Scott Michelfdc40a02009-02-17 22:15:04 +00002707
Chris Lattner516b9622006-09-14 20:50:57 +00002708 // If there is a mask here, and we have a variable shift, we can't be sure
2709 // that we're masking out the right stuff.
Gabor Greifba36cb52008-08-28 21:40:38 +00002710 if (LHSMask.getNode() || RHSMask.getNode())
Chris Lattner516b9622006-09-14 20:50:57 +00002711 return 0;
Scott Michelfdc40a02009-02-17 22:15:04 +00002712
Chris Lattner516b9622006-09-14 20:50:57 +00002713 // fold (or (shl x, y), (srl x, (sub 32, y))) -> (rotl x, y)
2714 // fold (or (shl x, y), (srl x, (sub 32, y))) -> (rotr x, (sub 32, y))
Scott Michelc9dc1142007-04-02 21:36:32 +00002715 if (RHSShiftAmt.getOpcode() == ISD::SUB &&
2716 LHSShiftAmt == RHSShiftAmt.getOperand(1)) {
Scott Michelfdc40a02009-02-17 22:15:04 +00002717 if (ConstantSDNode *SUBC =
Scott Michelc9dc1142007-04-02 21:36:32 +00002718 dyn_cast<ConstantSDNode>(RHSShiftAmt.getOperand(0))) {
Dan Gohman002e5d02008-03-13 22:13:53 +00002719 if (SUBC->getAPIntValue() == OpSizeInBits) {
Chris Lattner516b9622006-09-14 20:50:57 +00002720 if (HasROTL)
Bill Wendling317bd702009-01-30 21:14:50 +00002721 return DAG.getNode(ISD::ROTL, DL, VT,
2722 LHSShiftArg, LHSShiftAmt).getNode();
Chris Lattner516b9622006-09-14 20:50:57 +00002723 else
Bill Wendling317bd702009-01-30 21:14:50 +00002724 return DAG.getNode(ISD::ROTR, DL, VT,
2725 LHSShiftArg, RHSShiftAmt).getNode();
Anton Korobeynikov4c71dfe2008-02-20 11:10:28 +00002726 }
Chris Lattner516b9622006-09-14 20:50:57 +00002727 }
2728 }
Scott Michelfdc40a02009-02-17 22:15:04 +00002729
Chris Lattner516b9622006-09-14 20:50:57 +00002730 // fold (or (shl x, (sub 32, y)), (srl x, r)) -> (rotr x, y)
2731 // fold (or (shl x, (sub 32, y)), (srl x, r)) -> (rotl x, (sub 32, y))
Scott Michelc9dc1142007-04-02 21:36:32 +00002732 if (LHSShiftAmt.getOpcode() == ISD::SUB &&
2733 RHSShiftAmt == LHSShiftAmt.getOperand(1)) {
Scott Michelfdc40a02009-02-17 22:15:04 +00002734 if (ConstantSDNode *SUBC =
Scott Michelc9dc1142007-04-02 21:36:32 +00002735 dyn_cast<ConstantSDNode>(LHSShiftAmt.getOperand(0))) {
Dan Gohman002e5d02008-03-13 22:13:53 +00002736 if (SUBC->getAPIntValue() == OpSizeInBits) {
Bill Wendling2692d592008-08-31 01:13:31 +00002737 if (HasROTR)
Bill Wendling317bd702009-01-30 21:14:50 +00002738 return DAG.getNode(ISD::ROTR, DL, VT,
2739 LHSShiftArg, RHSShiftAmt).getNode();
Bill Wendling2692d592008-08-31 01:13:31 +00002740 else
Bill Wendling317bd702009-01-30 21:14:50 +00002741 return DAG.getNode(ISD::ROTL, DL, VT,
2742 LHSShiftArg, LHSShiftAmt).getNode();
Anton Korobeynikov4c71dfe2008-02-20 11:10:28 +00002743 }
Scott Michelc9dc1142007-04-02 21:36:32 +00002744 }
2745 }
2746
Dan Gohman74feef22008-10-17 01:23:35 +00002747 // Look for sign/zext/any-extended or truncate cases:
Scott Michelc9dc1142007-04-02 21:36:32 +00002748 if ((LHSShiftAmt.getOpcode() == ISD::SIGN_EXTEND
2749 || LHSShiftAmt.getOpcode() == ISD::ZERO_EXTEND
Dan Gohman74feef22008-10-17 01:23:35 +00002750 || LHSShiftAmt.getOpcode() == ISD::ANY_EXTEND
2751 || LHSShiftAmt.getOpcode() == ISD::TRUNCATE) &&
Scott Michelc9dc1142007-04-02 21:36:32 +00002752 (RHSShiftAmt.getOpcode() == ISD::SIGN_EXTEND
2753 || RHSShiftAmt.getOpcode() == ISD::ZERO_EXTEND
Dan Gohman74feef22008-10-17 01:23:35 +00002754 || RHSShiftAmt.getOpcode() == ISD::ANY_EXTEND
2755 || RHSShiftAmt.getOpcode() == ISD::TRUNCATE)) {
Dan Gohman475871a2008-07-27 21:46:04 +00002756 SDValue LExtOp0 = LHSShiftAmt.getOperand(0);
2757 SDValue RExtOp0 = RHSShiftAmt.getOperand(0);
Scott Michelc9dc1142007-04-02 21:36:32 +00002758 if (RExtOp0.getOpcode() == ISD::SUB &&
2759 RExtOp0.getOperand(1) == LExtOp0) {
2760 // fold (or (shl x, (*ext y)), (srl x, (*ext (sub 32, y)))) ->
Bill Wendlingc5cbda12008-08-31 00:37:27 +00002761 // (rotl x, y)
Scott Michelc9dc1142007-04-02 21:36:32 +00002762 // fold (or (shl x, (*ext y)), (srl x, (*ext (sub 32, y)))) ->
Bill Wendlingc5cbda12008-08-31 00:37:27 +00002763 // (rotr x, (sub 32, y))
Dan Gohman74feef22008-10-17 01:23:35 +00002764 if (ConstantSDNode *SUBC =
2765 dyn_cast<ConstantSDNode>(RExtOp0.getOperand(0))) {
Dan Gohman002e5d02008-03-13 22:13:53 +00002766 if (SUBC->getAPIntValue() == OpSizeInBits) {
Bill Wendling317bd702009-01-30 21:14:50 +00002767 return DAG.getNode(HasROTL ? ISD::ROTL : ISD::ROTR, DL, VT,
2768 LHSShiftArg,
Gabor Greif12632d22008-08-30 19:29:20 +00002769 HasROTL ? LHSShiftAmt : RHSShiftAmt).getNode();
Scott Michelc9dc1142007-04-02 21:36:32 +00002770 }
2771 }
2772 } else if (LExtOp0.getOpcode() == ISD::SUB &&
2773 RExtOp0 == LExtOp0.getOperand(1)) {
Scott Michelfdc40a02009-02-17 22:15:04 +00002774 // fold (or (shl x, (*ext (sub 32, y))), (srl x, (*ext y))) ->
Bill Wendlingc5cbda12008-08-31 00:37:27 +00002775 // (rotr x, y)
Bill Wendling353dea22008-08-31 01:04:56 +00002776 // fold (or (shl x, (*ext (sub 32, y))), (srl x, (*ext y))) ->
Bill Wendlingc5cbda12008-08-31 00:37:27 +00002777 // (rotl x, (sub 32, y))
Dan Gohman74feef22008-10-17 01:23:35 +00002778 if (ConstantSDNode *SUBC =
2779 dyn_cast<ConstantSDNode>(LExtOp0.getOperand(0))) {
Dan Gohman002e5d02008-03-13 22:13:53 +00002780 if (SUBC->getAPIntValue() == OpSizeInBits) {
Bill Wendling317bd702009-01-30 21:14:50 +00002781 return DAG.getNode(HasROTR ? ISD::ROTR : ISD::ROTL, DL, VT,
2782 LHSShiftArg,
Bill Wendling353dea22008-08-31 01:04:56 +00002783 HasROTR ? RHSShiftAmt : LHSShiftAmt).getNode();
Scott Michelc9dc1142007-04-02 21:36:32 +00002784 }
2785 }
Chris Lattner516b9622006-09-14 20:50:57 +00002786 }
2787 }
Scott Michelfdc40a02009-02-17 22:15:04 +00002788
Chris Lattner516b9622006-09-14 20:50:57 +00002789 return 0;
2790}
2791
Dan Gohman475871a2008-07-27 21:46:04 +00002792SDValue DAGCombiner::visitXOR(SDNode *N) {
2793 SDValue N0 = N->getOperand(0);
2794 SDValue N1 = N->getOperand(1);
2795 SDValue LHS, RHS, CC;
Nate Begeman646d7e22005-09-02 21:18:40 +00002796 ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0);
2797 ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1);
Owen Andersone50ed302009-08-10 22:56:29 +00002798 EVT VT = N0.getValueType();
Scott Michelfdc40a02009-02-17 22:15:04 +00002799
Dan Gohman7f321562007-06-25 16:23:39 +00002800 // fold vector ops
Duncan Sands83ec4b62008-06-06 12:08:01 +00002801 if (VT.isVector()) {
Dan Gohman475871a2008-07-27 21:46:04 +00002802 SDValue FoldedVOp = SimplifyVBinOp(N);
Gabor Greifba36cb52008-08-28 21:40:38 +00002803 if (FoldedVOp.getNode()) return FoldedVOp;
Dan Gohman05d92fe2007-07-13 20:03:40 +00002804 }
Scott Michelfdc40a02009-02-17 22:15:04 +00002805
Evan Cheng26471c42008-03-25 20:08:07 +00002806 // fold (xor undef, undef) -> 0. This is a common idiom (misuse).
2807 if (N0.getOpcode() == ISD::UNDEF && N1.getOpcode() == ISD::UNDEF)
2808 return DAG.getConstant(0, VT);
Dan Gohman613e0d82007-07-03 14:03:57 +00002809 // fold (xor x, undef) -> undef
Dan Gohman70fb1ae2007-07-10 15:19:29 +00002810 if (N0.getOpcode() == ISD::UNDEF)
2811 return N0;
2812 if (N1.getOpcode() == ISD::UNDEF)
Dan Gohman613e0d82007-07-03 14:03:57 +00002813 return N1;
Nate Begeman1d4d4142005-09-01 00:19:25 +00002814 // fold (xor c1, c2) -> c1^c2
Nate Begeman646d7e22005-09-02 21:18:40 +00002815 if (N0C && N1C)
Bill Wendlingf3cbca22008-09-24 10:25:02 +00002816 return DAG.FoldConstantArithmetic(ISD::XOR, VT, N0C, N1C);
Nate Begeman99801192005-09-07 23:25:52 +00002817 // canonicalize constant to RHS
Nate Begemana0e221d2005-10-18 00:28:13 +00002818 if (N0C && !N1C)
Bill Wendling317bd702009-01-30 21:14:50 +00002819 return DAG.getNode(ISD::XOR, N->getDebugLoc(), VT, N1, N0);
Nate Begeman1d4d4142005-09-01 00:19:25 +00002820 // fold (xor x, 0) -> x
Nate Begeman646d7e22005-09-02 21:18:40 +00002821 if (N1C && N1C->isNullValue())
Nate Begeman83e75ec2005-09-06 04:43:02 +00002822 return N0;
Nate Begemancd4d58c2006-02-03 06:46:56 +00002823 // reassociate xor
Bill Wendling35247c32009-01-30 00:45:56 +00002824 SDValue RXOR = ReassociateOps(ISD::XOR, N->getDebugLoc(), N0, N1);
Gabor Greifba36cb52008-08-28 21:40:38 +00002825 if (RXOR.getNode() != 0)
Nate Begemancd4d58c2006-02-03 06:46:56 +00002826 return RXOR;
Bill Wendlingae89bb12008-11-11 08:25:46 +00002827
Nate Begeman1d4d4142005-09-01 00:19:25 +00002828 // fold !(x cc y) -> (x !cc y)
Dan Gohman002e5d02008-03-13 22:13:53 +00002829 if (N1C && N1C->getAPIntValue() == 1 && isSetCCEquivalent(N0, LHS, RHS, CC)) {
Duncan Sands83ec4b62008-06-06 12:08:01 +00002830 bool isInt = LHS.getValueType().isInteger();
Nate Begeman646d7e22005-09-02 21:18:40 +00002831 ISD::CondCode NotCC = ISD::getSetCCInverse(cast<CondCodeSDNode>(CC)->get(),
2832 isInt);
Bill Wendlingae89bb12008-11-11 08:25:46 +00002833
Duncan Sands25cf2272008-11-24 14:53:14 +00002834 if (!LegalOperations || TLI.isCondCodeLegal(NotCC, LHS.getValueType())) {
Bill Wendlingae89bb12008-11-11 08:25:46 +00002835 switch (N0.getOpcode()) {
2836 default:
Torok Edwinc23197a2009-07-14 16:55:14 +00002837 llvm_unreachable("Unhandled SetCC Equivalent!");
Bill Wendlingae89bb12008-11-11 08:25:46 +00002838 case ISD::SETCC:
Bill Wendling317bd702009-01-30 21:14:50 +00002839 return DAG.getSetCC(N->getDebugLoc(), VT, LHS, RHS, NotCC);
Bill Wendlingae89bb12008-11-11 08:25:46 +00002840 case ISD::SELECT_CC:
Bill Wendling317bd702009-01-30 21:14:50 +00002841 return DAG.getSelectCC(N->getDebugLoc(), LHS, RHS, N0.getOperand(2),
Bill Wendlingae89bb12008-11-11 08:25:46 +00002842 N0.getOperand(3), NotCC);
2843 }
2844 }
Nate Begeman1d4d4142005-09-01 00:19:25 +00002845 }
Bill Wendlingae89bb12008-11-11 08:25:46 +00002846
Chris Lattner61c5ff42007-09-10 21:39:07 +00002847 // fold (not (zext (setcc x, y))) -> (zext (not (setcc x, y)))
Dan Gohman002e5d02008-03-13 22:13:53 +00002848 if (N1C && N1C->getAPIntValue() == 1 && N0.getOpcode() == ISD::ZERO_EXTEND &&
Gabor Greif12632d22008-08-30 19:29:20 +00002849 N0.getNode()->hasOneUse() &&
2850 isSetCCEquivalent(N0.getOperand(0), LHS, RHS, CC)){
Dan Gohman475871a2008-07-27 21:46:04 +00002851 SDValue V = N0.getOperand(0);
Scott Michelfdc40a02009-02-17 22:15:04 +00002852 V = DAG.getNode(ISD::XOR, N0.getDebugLoc(), V.getValueType(), V,
Duncan Sands272dce02007-10-10 09:54:50 +00002853 DAG.getConstant(1, V.getValueType()));
Gabor Greifba36cb52008-08-28 21:40:38 +00002854 AddToWorkList(V.getNode());
Bill Wendling317bd702009-01-30 21:14:50 +00002855 return DAG.getNode(ISD::ZERO_EXTEND, N->getDebugLoc(), VT, V);
Chris Lattner61c5ff42007-09-10 21:39:07 +00002856 }
Scott Michelfdc40a02009-02-17 22:15:04 +00002857
Bill Wendling317bd702009-01-30 21:14:50 +00002858 // fold (not (or x, y)) -> (and (not x), (not y)) iff x or y are setcc
Owen Anderson825b72b2009-08-11 20:47:22 +00002859 if (N1C && N1C->getAPIntValue() == 1 && VT == MVT::i1 &&
Nate Begeman99801192005-09-07 23:25:52 +00002860 (N0.getOpcode() == ISD::OR || N0.getOpcode() == ISD::AND)) {
Dan Gohman475871a2008-07-27 21:46:04 +00002861 SDValue LHS = N0.getOperand(0), RHS = N0.getOperand(1);
Nate Begeman99801192005-09-07 23:25:52 +00002862 if (isOneUseSetCC(RHS) || isOneUseSetCC(LHS)) {
2863 unsigned NewOpcode = N0.getOpcode() == ISD::AND ? ISD::OR : ISD::AND;
Bill Wendling317bd702009-01-30 21:14:50 +00002864 LHS = DAG.getNode(ISD::XOR, LHS.getDebugLoc(), VT, LHS, N1); // LHS = ~LHS
2865 RHS = DAG.getNode(ISD::XOR, RHS.getDebugLoc(), VT, RHS, N1); // RHS = ~RHS
Gabor Greifba36cb52008-08-28 21:40:38 +00002866 AddToWorkList(LHS.getNode()); AddToWorkList(RHS.getNode());
Bill Wendling317bd702009-01-30 21:14:50 +00002867 return DAG.getNode(NewOpcode, N->getDebugLoc(), VT, LHS, RHS);
Nate Begeman1d4d4142005-09-01 00:19:25 +00002868 }
2869 }
Bill Wendling317bd702009-01-30 21:14:50 +00002870 // fold (not (or x, y)) -> (and (not x), (not y)) iff x or y are constants
Scott Michelfdc40a02009-02-17 22:15:04 +00002871 if (N1C && N1C->isAllOnesValue() &&
Nate Begeman99801192005-09-07 23:25:52 +00002872 (N0.getOpcode() == ISD::OR || N0.getOpcode() == ISD::AND)) {
Dan Gohman475871a2008-07-27 21:46:04 +00002873 SDValue LHS = N0.getOperand(0), RHS = N0.getOperand(1);
Nate Begeman99801192005-09-07 23:25:52 +00002874 if (isa<ConstantSDNode>(RHS) || isa<ConstantSDNode>(LHS)) {
2875 unsigned NewOpcode = N0.getOpcode() == ISD::AND ? ISD::OR : ISD::AND;
Bill Wendling317bd702009-01-30 21:14:50 +00002876 LHS = DAG.getNode(ISD::XOR, LHS.getDebugLoc(), VT, LHS, N1); // LHS = ~LHS
2877 RHS = DAG.getNode(ISD::XOR, RHS.getDebugLoc(), VT, RHS, N1); // RHS = ~RHS
Gabor Greifba36cb52008-08-28 21:40:38 +00002878 AddToWorkList(LHS.getNode()); AddToWorkList(RHS.getNode());
Bill Wendling317bd702009-01-30 21:14:50 +00002879 return DAG.getNode(NewOpcode, N->getDebugLoc(), VT, LHS, RHS);
Nate Begeman1d4d4142005-09-01 00:19:25 +00002880 }
2881 }
Bill Wendling317bd702009-01-30 21:14:50 +00002882 // fold (xor (xor x, c1), c2) -> (xor x, (xor c1, c2))
Nate Begeman223df222005-09-08 20:18:10 +00002883 if (N1C && N0.getOpcode() == ISD::XOR) {
2884 ConstantSDNode *N00C = dyn_cast<ConstantSDNode>(N0.getOperand(0));
2885 ConstantSDNode *N01C = dyn_cast<ConstantSDNode>(N0.getOperand(1));
2886 if (N00C)
Bill Wendling317bd702009-01-30 21:14:50 +00002887 return DAG.getNode(ISD::XOR, N->getDebugLoc(), VT, N0.getOperand(1),
2888 DAG.getConstant(N1C->getAPIntValue() ^
Dan Gohman002e5d02008-03-13 22:13:53 +00002889 N00C->getAPIntValue(), VT));
Nate Begeman223df222005-09-08 20:18:10 +00002890 if (N01C)
Bill Wendling317bd702009-01-30 21:14:50 +00002891 return DAG.getNode(ISD::XOR, N->getDebugLoc(), VT, N0.getOperand(0),
2892 DAG.getConstant(N1C->getAPIntValue() ^
Dan Gohman002e5d02008-03-13 22:13:53 +00002893 N01C->getAPIntValue(), VT));
Nate Begeman223df222005-09-08 20:18:10 +00002894 }
2895 // fold (xor x, x) -> 0
Eric Christopher7bccf6a2011-02-16 04:50:12 +00002896 if (N0 == N1)
2897 return tryFoldToZero(N->getDebugLoc(), TLI, VT, DAG, LegalOperations);
Scott Michelfdc40a02009-02-17 22:15:04 +00002898
Chris Lattner35e5c142006-05-05 05:51:50 +00002899 // Simplify: xor (op x...), (op y...) -> (op (xor x, y))
2900 if (N0.getOpcode() == N1.getOpcode()) {
Dan Gohman475871a2008-07-27 21:46:04 +00002901 SDValue Tmp = SimplifyBinOpWithSameOpcodeHands(N);
Gabor Greifba36cb52008-08-28 21:40:38 +00002902 if (Tmp.getNode()) return Tmp;
Nate Begeman39ee1ac2005-09-09 19:49:52 +00002903 }
Scott Michelfdc40a02009-02-17 22:15:04 +00002904
Chris Lattner3e104b12006-04-08 04:15:24 +00002905 // Simplify the expression using non-local knowledge.
Duncan Sands83ec4b62008-06-06 12:08:01 +00002906 if (!VT.isVector() &&
Dan Gohman475871a2008-07-27 21:46:04 +00002907 SimplifyDemandedBits(SDValue(N, 0)))
2908 return SDValue(N, 0);
Scott Michelfdc40a02009-02-17 22:15:04 +00002909
Evan Chengb3a3d5e2010-04-28 07:10:39 +00002910 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00002911}
2912
Chris Lattnere70da202007-12-06 07:33:36 +00002913/// visitShiftByConstant - Handle transforms common to the three shifts, when
2914/// the shift amount is a constant.
Dan Gohman475871a2008-07-27 21:46:04 +00002915SDValue DAGCombiner::visitShiftByConstant(SDNode *N, unsigned Amt) {
Gabor Greifba36cb52008-08-28 21:40:38 +00002916 SDNode *LHS = N->getOperand(0).getNode();
Dan Gohman475871a2008-07-27 21:46:04 +00002917 if (!LHS->hasOneUse()) return SDValue();
Scott Michelfdc40a02009-02-17 22:15:04 +00002918
Chris Lattnere70da202007-12-06 07:33:36 +00002919 // We want to pull some binops through shifts, so that we have (and (shift))
2920 // instead of (shift (and)), likewise for add, or, xor, etc. This sort of
2921 // thing happens with address calculations, so it's important to canonicalize
2922 // it.
2923 bool HighBitSet = false; // Can we transform this if the high bit is set?
Scott Michelfdc40a02009-02-17 22:15:04 +00002924
Chris Lattnere70da202007-12-06 07:33:36 +00002925 switch (LHS->getOpcode()) {
Dan Gohman475871a2008-07-27 21:46:04 +00002926 default: return SDValue();
Chris Lattnere70da202007-12-06 07:33:36 +00002927 case ISD::OR:
2928 case ISD::XOR:
2929 HighBitSet = false; // We can only transform sra if the high bit is clear.
2930 break;
2931 case ISD::AND:
2932 HighBitSet = true; // We can only transform sra if the high bit is set.
2933 break;
2934 case ISD::ADD:
Scott Michelfdc40a02009-02-17 22:15:04 +00002935 if (N->getOpcode() != ISD::SHL)
Dan Gohman475871a2008-07-27 21:46:04 +00002936 return SDValue(); // only shl(add) not sr[al](add).
Chris Lattnere70da202007-12-06 07:33:36 +00002937 HighBitSet = false; // We can only transform sra if the high bit is clear.
2938 break;
2939 }
Scott Michelfdc40a02009-02-17 22:15:04 +00002940
Chris Lattnere70da202007-12-06 07:33:36 +00002941 // We require the RHS of the binop to be a constant as well.
2942 ConstantSDNode *BinOpCst = dyn_cast<ConstantSDNode>(LHS->getOperand(1));
Dan Gohman475871a2008-07-27 21:46:04 +00002943 if (!BinOpCst) return SDValue();
Bill Wendling88103372009-01-30 21:37:17 +00002944
2945 // FIXME: disable this unless the input to the binop is a shift by a constant.
2946 // If it is not a shift, it pessimizes some common cases like:
Chris Lattnerd3fd6d22007-12-06 07:47:55 +00002947 //
Bill Wendling88103372009-01-30 21:37:17 +00002948 // void foo(int *X, int i) { X[i & 1235] = 1; }
2949 // int bar(int *X, int i) { return X[i & 255]; }
Gabor Greifba36cb52008-08-28 21:40:38 +00002950 SDNode *BinOpLHSVal = LHS->getOperand(0).getNode();
Scott Michelfdc40a02009-02-17 22:15:04 +00002951 if ((BinOpLHSVal->getOpcode() != ISD::SHL &&
Chris Lattnerd3fd6d22007-12-06 07:47:55 +00002952 BinOpLHSVal->getOpcode() != ISD::SRA &&
2953 BinOpLHSVal->getOpcode() != ISD::SRL) ||
2954 !isa<ConstantSDNode>(BinOpLHSVal->getOperand(1)))
Dan Gohman475871a2008-07-27 21:46:04 +00002955 return SDValue();
Scott Michelfdc40a02009-02-17 22:15:04 +00002956
Owen Andersone50ed302009-08-10 22:56:29 +00002957 EVT VT = N->getValueType(0);
Scott Michelfdc40a02009-02-17 22:15:04 +00002958
Bill Wendling88103372009-01-30 21:37:17 +00002959 // If this is a signed shift right, and the high bit is modified by the
2960 // logical operation, do not perform the transformation. The highBitSet
2961 // boolean indicates the value of the high bit of the constant which would
2962 // cause it to be modified for this operation.
Chris Lattnere70da202007-12-06 07:33:36 +00002963 if (N->getOpcode() == ISD::SRA) {
Dan Gohman220a8232008-03-03 23:51:38 +00002964 bool BinOpRHSSignSet = BinOpCst->getAPIntValue().isNegative();
2965 if (BinOpRHSSignSet != HighBitSet)
Dan Gohman475871a2008-07-27 21:46:04 +00002966 return SDValue();
Chris Lattnere70da202007-12-06 07:33:36 +00002967 }
Scott Michelfdc40a02009-02-17 22:15:04 +00002968
Chris Lattnere70da202007-12-06 07:33:36 +00002969 // Fold the constants, shifting the binop RHS by the shift amount.
Bill Wendling88103372009-01-30 21:37:17 +00002970 SDValue NewRHS = DAG.getNode(N->getOpcode(), LHS->getOperand(1).getDebugLoc(),
2971 N->getValueType(0),
2972 LHS->getOperand(1), N->getOperand(1));
Chris Lattnere70da202007-12-06 07:33:36 +00002973
2974 // Create the new shift.
Eric Christopher503a64d2010-12-09 04:48:06 +00002975 SDValue NewShift = DAG.getNode(N->getOpcode(),
2976 LHS->getOperand(0).getDebugLoc(),
Bill Wendling88103372009-01-30 21:37:17 +00002977 VT, LHS->getOperand(0), N->getOperand(1));
Chris Lattnere70da202007-12-06 07:33:36 +00002978
2979 // Create the new binop.
Bill Wendling88103372009-01-30 21:37:17 +00002980 return DAG.getNode(LHS->getOpcode(), N->getDebugLoc(), VT, NewShift, NewRHS);
Chris Lattnere70da202007-12-06 07:33:36 +00002981}
2982
Dan Gohman475871a2008-07-27 21:46:04 +00002983SDValue DAGCombiner::visitSHL(SDNode *N) {
2984 SDValue N0 = N->getOperand(0);
2985 SDValue N1 = N->getOperand(1);
Nate Begeman646d7e22005-09-02 21:18:40 +00002986 ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0);
2987 ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1);
Owen Andersone50ed302009-08-10 22:56:29 +00002988 EVT VT = N0.getValueType();
Dan Gohman87862e72009-12-11 21:31:27 +00002989 unsigned OpSizeInBits = VT.getScalarType().getSizeInBits();
Scott Michelfdc40a02009-02-17 22:15:04 +00002990
Nate Begeman1d4d4142005-09-01 00:19:25 +00002991 // fold (shl c1, c2) -> c1<<c2
Nate Begeman646d7e22005-09-02 21:18:40 +00002992 if (N0C && N1C)
Bill Wendlingf3cbca22008-09-24 10:25:02 +00002993 return DAG.FoldConstantArithmetic(ISD::SHL, VT, N0C, N1C);
Nate Begeman1d4d4142005-09-01 00:19:25 +00002994 // fold (shl 0, x) -> 0
Nate Begeman646d7e22005-09-02 21:18:40 +00002995 if (N0C && N0C->isNullValue())
Nate Begeman83e75ec2005-09-06 04:43:02 +00002996 return N0;
Nate Begeman1d4d4142005-09-01 00:19:25 +00002997 // fold (shl x, c >= size(x)) -> undef
Dan Gohmanf5aeb1a2008-09-12 16:56:44 +00002998 if (N1C && N1C->getZExtValue() >= OpSizeInBits)
Dale Johannesene8d72302009-02-06 23:05:02 +00002999 return DAG.getUNDEF(VT);
Nate Begeman1d4d4142005-09-01 00:19:25 +00003000 // fold (shl x, 0) -> x
Nate Begeman646d7e22005-09-02 21:18:40 +00003001 if (N1C && N1C->isNullValue())
Nate Begeman83e75ec2005-09-06 04:43:02 +00003002 return N0;
Nate Begeman1d4d4142005-09-01 00:19:25 +00003003 // if (shl x, c) is known to be zero, return 0
Dan Gohman475871a2008-07-27 21:46:04 +00003004 if (DAG.MaskedValueIsZero(SDValue(N, 0),
Dan Gohman87862e72009-12-11 21:31:27 +00003005 APInt::getAllOnesValue(OpSizeInBits)))
Nate Begeman83e75ec2005-09-06 04:43:02 +00003006 return DAG.getConstant(0, VT);
Duncan Sandsb0d5cdd2009-02-01 18:06:53 +00003007 // fold (shl x, (trunc (and y, c))) -> (shl x, (and (trunc y), (trunc c))).
Evan Chengeb9f8922008-08-30 02:03:58 +00003008 if (N1.getOpcode() == ISD::TRUNCATE &&
Evan Cheng242ebd12008-09-22 18:19:24 +00003009 N1.getOperand(0).getOpcode() == ISD::AND &&
3010 N1.hasOneUse() && N1.getOperand(0).hasOneUse()) {
Evan Chengeb9f8922008-08-30 02:03:58 +00003011 SDValue N101 = N1.getOperand(0).getOperand(1);
Evan Cheng242ebd12008-09-22 18:19:24 +00003012 if (ConstantSDNode *N101C = dyn_cast<ConstantSDNode>(N101)) {
Owen Andersone50ed302009-08-10 22:56:29 +00003013 EVT TruncVT = N1.getValueType();
Evan Cheng242ebd12008-09-22 18:19:24 +00003014 SDValue N100 = N1.getOperand(0).getOperand(0);
Duncan Sandsb0d5cdd2009-02-01 18:06:53 +00003015 APInt TruncC = N101C->getAPIntValue();
Jay Foad40f8f622010-12-07 08:25:19 +00003016 TruncC = TruncC.trunc(TruncVT.getSizeInBits());
Bill Wendling88103372009-01-30 21:37:17 +00003017 return DAG.getNode(ISD::SHL, N->getDebugLoc(), VT, N0,
Bill Wendlingfc4b6772009-02-01 11:19:36 +00003018 DAG.getNode(ISD::AND, N->getDebugLoc(), TruncVT,
3019 DAG.getNode(ISD::TRUNCATE,
3020 N->getDebugLoc(),
3021 TruncVT, N100),
Dan Gohmance9bc122009-01-27 20:39:34 +00003022 DAG.getConstant(TruncC, TruncVT)));
Evan Chengeb9f8922008-08-30 02:03:58 +00003023 }
3024 }
3025
Dan Gohman475871a2008-07-27 21:46:04 +00003026 if (N1C && SimplifyDemandedBits(SDValue(N, 0)))
3027 return SDValue(N, 0);
Bill Wendling88103372009-01-30 21:37:17 +00003028
3029 // fold (shl (shl x, c1), c2) -> 0 or (shl x, (add c1, c2))
Scott Michelfdc40a02009-02-17 22:15:04 +00003030 if (N1C && N0.getOpcode() == ISD::SHL &&
Nate Begeman1d4d4142005-09-01 00:19:25 +00003031 N0.getOperand(1).getOpcode() == ISD::Constant) {
Dan Gohmanf5aeb1a2008-09-12 16:56:44 +00003032 uint64_t c1 = cast<ConstantSDNode>(N0.getOperand(1))->getZExtValue();
3033 uint64_t c2 = N1C->getZExtValue();
Dale Johannesenc72b18c2010-12-21 21:55:50 +00003034 if (c1 + c2 >= OpSizeInBits)
Nate Begeman83e75ec2005-09-06 04:43:02 +00003035 return DAG.getConstant(0, VT);
Bill Wendling88103372009-01-30 21:37:17 +00003036 return DAG.getNode(ISD::SHL, N->getDebugLoc(), VT, N0.getOperand(0),
Nate Begeman83e75ec2005-09-06 04:43:02 +00003037 DAG.getConstant(c1 + c2, N1.getValueType()));
Nate Begeman1d4d4142005-09-01 00:19:25 +00003038 }
Dale Johannesenc72b18c2010-12-21 21:55:50 +00003039
3040 // fold (shl (ext (shl x, c1)), c2) -> (ext (shl x, (add c1, c2)))
3041 // For this to be valid, the second form must not preserve any of the bits
3042 // that are shifted out by the inner shift in the first form. This means
3043 // the outer shift size must be >= the number of bits added by the ext.
3044 // As a corollary, we don't care what kind of ext it is.
3045 if (N1C && (N0.getOpcode() == ISD::ZERO_EXTEND ||
3046 N0.getOpcode() == ISD::ANY_EXTEND ||
3047 N0.getOpcode() == ISD::SIGN_EXTEND) &&
3048 N0.getOperand(0).getOpcode() == ISD::SHL &&
3049 isa<ConstantSDNode>(N0.getOperand(0)->getOperand(1))) {
Owen Anderson95771af2011-02-25 21:41:48 +00003050 uint64_t c1 =
Dale Johannesenc72b18c2010-12-21 21:55:50 +00003051 cast<ConstantSDNode>(N0.getOperand(0)->getOperand(1))->getZExtValue();
3052 uint64_t c2 = N1C->getZExtValue();
3053 EVT InnerShiftVT = N0.getOperand(0).getValueType();
3054 uint64_t InnerShiftSize = InnerShiftVT.getScalarType().getSizeInBits();
3055 if (c2 >= OpSizeInBits - InnerShiftSize) {
3056 if (c1 + c2 >= OpSizeInBits)
3057 return DAG.getConstant(0, VT);
3058 return DAG.getNode(ISD::SHL, N0->getDebugLoc(), VT,
3059 DAG.getNode(N0.getOpcode(), N0->getDebugLoc(), VT,
3060 N0.getOperand(0)->getOperand(0)),
3061 DAG.getConstant(c1 + c2, N1.getValueType()));
3062 }
3063 }
3064
Bill Wendling88103372009-01-30 21:37:17 +00003065 // fold (shl (srl x, c1), c2) -> (shl (and x, (shl -1, c1)), (sub c2, c1)) or
3066 // (srl (and x, (shl -1, c1)), (sub c1, c2))
Scott Michelfdc40a02009-02-17 22:15:04 +00003067 if (N1C && N0.getOpcode() == ISD::SRL &&
Nate Begeman1d4d4142005-09-01 00:19:25 +00003068 N0.getOperand(1).getOpcode() == ISD::Constant) {
Dan Gohmanf5aeb1a2008-09-12 16:56:44 +00003069 uint64_t c1 = cast<ConstantSDNode>(N0.getOperand(1))->getZExtValue();
Evan Chengd101a722009-07-21 05:40:15 +00003070 if (c1 < VT.getSizeInBits()) {
3071 uint64_t c2 = N1C->getZExtValue();
Dan Gohman5cbd37e2009-08-06 09:18:59 +00003072 SDValue HiBitsMask =
3073 DAG.getConstant(APInt::getHighBitsSet(VT.getSizeInBits(),
3074 VT.getSizeInBits() - c1),
3075 VT);
Evan Chengd101a722009-07-21 05:40:15 +00003076 SDValue Mask = DAG.getNode(ISD::AND, N0.getDebugLoc(), VT,
3077 N0.getOperand(0),
Dan Gohman5cbd37e2009-08-06 09:18:59 +00003078 HiBitsMask);
Evan Chengd101a722009-07-21 05:40:15 +00003079 if (c2 > c1)
3080 return DAG.getNode(ISD::SHL, N->getDebugLoc(), VT, Mask,
3081 DAG.getConstant(c2-c1, N1.getValueType()));
3082 else
3083 return DAG.getNode(ISD::SRL, N->getDebugLoc(), VT, Mask,
3084 DAG.getConstant(c1-c2, N1.getValueType()));
3085 }
Nate Begeman1d4d4142005-09-01 00:19:25 +00003086 }
Bill Wendling88103372009-01-30 21:37:17 +00003087 // fold (shl (sra x, c1), c1) -> (and x, (shl -1, c1))
Dan Gohman5cbd37e2009-08-06 09:18:59 +00003088 if (N1C && N0.getOpcode() == ISD::SRA && N1 == N0.getOperand(1)) {
3089 SDValue HiBitsMask =
3090 DAG.getConstant(APInt::getHighBitsSet(VT.getSizeInBits(),
3091 VT.getSizeInBits() -
3092 N1C->getZExtValue()),
3093 VT);
Bill Wendling88103372009-01-30 21:37:17 +00003094 return DAG.getNode(ISD::AND, N->getDebugLoc(), VT, N0.getOperand(0),
Dan Gohman5cbd37e2009-08-06 09:18:59 +00003095 HiBitsMask);
3096 }
Scott Michelfdc40a02009-02-17 22:15:04 +00003097
Evan Chenge5b51ac2010-04-17 06:13:15 +00003098 if (N1C) {
3099 SDValue NewSHL = visitShiftByConstant(N, N1C->getZExtValue());
3100 if (NewSHL.getNode())
3101 return NewSHL;
3102 }
3103
Evan Chengb3a3d5e2010-04-28 07:10:39 +00003104 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00003105}
3106
Dan Gohman475871a2008-07-27 21:46:04 +00003107SDValue DAGCombiner::visitSRA(SDNode *N) {
3108 SDValue N0 = N->getOperand(0);
3109 SDValue N1 = N->getOperand(1);
Nate Begeman646d7e22005-09-02 21:18:40 +00003110 ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0);
3111 ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1);
Owen Andersone50ed302009-08-10 22:56:29 +00003112 EVT VT = N0.getValueType();
Dan Gohman87862e72009-12-11 21:31:27 +00003113 unsigned OpSizeInBits = VT.getScalarType().getSizeInBits();
Scott Michelfdc40a02009-02-17 22:15:04 +00003114
Bill Wendling88103372009-01-30 21:37:17 +00003115 // fold (sra c1, c2) -> (sra c1, c2)
Nate Begeman646d7e22005-09-02 21:18:40 +00003116 if (N0C && N1C)
Bill Wendlingf3cbca22008-09-24 10:25:02 +00003117 return DAG.FoldConstantArithmetic(ISD::SRA, VT, N0C, N1C);
Nate Begeman1d4d4142005-09-01 00:19:25 +00003118 // fold (sra 0, x) -> 0
Nate Begeman646d7e22005-09-02 21:18:40 +00003119 if (N0C && N0C->isNullValue())
Nate Begeman83e75ec2005-09-06 04:43:02 +00003120 return N0;
Nate Begeman1d4d4142005-09-01 00:19:25 +00003121 // fold (sra -1, x) -> -1
Nate Begeman646d7e22005-09-02 21:18:40 +00003122 if (N0C && N0C->isAllOnesValue())
Nate Begeman83e75ec2005-09-06 04:43:02 +00003123 return N0;
Bill Wendling88103372009-01-30 21:37:17 +00003124 // fold (sra x, (setge c, size(x))) -> undef
Dan Gohman87862e72009-12-11 21:31:27 +00003125 if (N1C && N1C->getZExtValue() >= OpSizeInBits)
Dale Johannesene8d72302009-02-06 23:05:02 +00003126 return DAG.getUNDEF(VT);
Nate Begeman1d4d4142005-09-01 00:19:25 +00003127 // fold (sra x, 0) -> x
Nate Begeman646d7e22005-09-02 21:18:40 +00003128 if (N1C && N1C->isNullValue())
Nate Begeman83e75ec2005-09-06 04:43:02 +00003129 return N0;
Nate Begemanfb7217b2006-02-17 19:54:08 +00003130 // fold (sra (shl x, c1), c1) -> sext_inreg for some c1 and target supports
3131 // sext_inreg.
3132 if (N1C && N0.getOpcode() == ISD::SHL && N1 == N0.getOperand(1)) {
Dan Gohman87862e72009-12-11 21:31:27 +00003133 unsigned LowBits = OpSizeInBits - (unsigned)N1C->getZExtValue();
Dan Gohmand1996362010-01-09 02:13:55 +00003134 EVT ExtVT = EVT::getIntegerVT(*DAG.getContext(), LowBits);
3135 if (VT.isVector())
3136 ExtVT = EVT::getVectorVT(*DAG.getContext(),
3137 ExtVT, VT.getVectorNumElements());
3138 if ((!LegalOperations ||
3139 TLI.isOperationLegal(ISD::SIGN_EXTEND_INREG, ExtVT)))
Bill Wendling88103372009-01-30 21:37:17 +00003140 return DAG.getNode(ISD::SIGN_EXTEND_INREG, N->getDebugLoc(), VT,
Dan Gohmand1996362010-01-09 02:13:55 +00003141 N0.getOperand(0), DAG.getValueType(ExtVT));
Nate Begemanfb7217b2006-02-17 19:54:08 +00003142 }
Duncan Sandsd4b9c172008-06-13 19:07:40 +00003143
Bill Wendling88103372009-01-30 21:37:17 +00003144 // fold (sra (sra x, c1), c2) -> (sra x, (add c1, c2))
Chris Lattner71d9ebc2006-02-28 06:23:04 +00003145 if (N1C && N0.getOpcode() == ISD::SRA) {
3146 if (ConstantSDNode *C1 = dyn_cast<ConstantSDNode>(N0.getOperand(1))) {
Dan Gohmanf5aeb1a2008-09-12 16:56:44 +00003147 unsigned Sum = N1C->getZExtValue() + C1->getZExtValue();
Dan Gohman87862e72009-12-11 21:31:27 +00003148 if (Sum >= OpSizeInBits) Sum = OpSizeInBits-1;
Bill Wendling88103372009-01-30 21:37:17 +00003149 return DAG.getNode(ISD::SRA, N->getDebugLoc(), VT, N0.getOperand(0),
Chris Lattner71d9ebc2006-02-28 06:23:04 +00003150 DAG.getConstant(Sum, N1C->getValueType(0)));
3151 }
3152 }
Christopher Lamb15cbde32008-03-19 08:30:06 +00003153
Bill Wendling88103372009-01-30 21:37:17 +00003154 // fold (sra (shl X, m), (sub result_size, n))
3155 // -> (sign_extend (trunc (shl X, (sub (sub result_size, n), m)))) for
Scott Michelfdc40a02009-02-17 22:15:04 +00003156 // result_size - n != m.
3157 // If truncate is free for the target sext(shl) is likely to result in better
Christopher Lambb9b04282008-03-20 04:31:39 +00003158 // code.
Christopher Lamb15cbde32008-03-19 08:30:06 +00003159 if (N0.getOpcode() == ISD::SHL) {
3160 // Get the two constanst of the shifts, CN0 = m, CN = n.
3161 const ConstantSDNode *N01C = dyn_cast<ConstantSDNode>(N0.getOperand(1));
3162 if (N01C && N1C) {
Christopher Lambb9b04282008-03-20 04:31:39 +00003163 // Determine what the truncate's result bitsize and type would be.
Owen Andersone50ed302009-08-10 22:56:29 +00003164 EVT TruncVT =
Eric Christopher503a64d2010-12-09 04:48:06 +00003165 EVT::getIntegerVT(*DAG.getContext(),
3166 OpSizeInBits - N1C->getZExtValue());
Christopher Lambb9b04282008-03-20 04:31:39 +00003167 // Determine the residual right-shift amount.
Torok Edwin6bb49582009-05-23 17:29:48 +00003168 signed ShiftAmt = N1C->getZExtValue() - N01C->getZExtValue();
Duncan Sandsd4b9c172008-06-13 19:07:40 +00003169
Scott Michelfdc40a02009-02-17 22:15:04 +00003170 // If the shift is not a no-op (in which case this should be just a sign
3171 // extend already), the truncated to type is legal, sign_extend is legal
Dan Gohmanf451cb82010-02-10 16:03:48 +00003172 // on that type, and the truncate to that type is both legal and free,
Christopher Lambb9b04282008-03-20 04:31:39 +00003173 // perform the transform.
Torok Edwin6bb49582009-05-23 17:29:48 +00003174 if ((ShiftAmt > 0) &&
Dan Gohmanf560ffa2009-01-28 17:46:25 +00003175 TLI.isOperationLegalOrCustom(ISD::SIGN_EXTEND, TruncVT) &&
3176 TLI.isOperationLegalOrCustom(ISD::TRUNCATE, VT) &&
Evan Cheng260e07e2008-03-20 02:18:41 +00003177 TLI.isTruncateFree(VT, TruncVT)) {
Christopher Lambb9b04282008-03-20 04:31:39 +00003178
Owen Anderson95771af2011-02-25 21:41:48 +00003179 SDValue Amt = DAG.getConstant(ShiftAmt,
3180 getShiftAmountTy(N0.getOperand(0).getValueType()));
Bill Wendling88103372009-01-30 21:37:17 +00003181 SDValue Shift = DAG.getNode(ISD::SRL, N0.getDebugLoc(), VT,
3182 N0.getOperand(0), Amt);
3183 SDValue Trunc = DAG.getNode(ISD::TRUNCATE, N0.getDebugLoc(), TruncVT,
3184 Shift);
3185 return DAG.getNode(ISD::SIGN_EXTEND, N->getDebugLoc(),
3186 N->getValueType(0), Trunc);
Christopher Lamb15cbde32008-03-19 08:30:06 +00003187 }
3188 }
3189 }
Scott Michelfdc40a02009-02-17 22:15:04 +00003190
Duncan Sandsb0d5cdd2009-02-01 18:06:53 +00003191 // fold (sra x, (trunc (and y, c))) -> (sra x, (and (trunc y), (trunc c))).
Evan Chengeb9f8922008-08-30 02:03:58 +00003192 if (N1.getOpcode() == ISD::TRUNCATE &&
Evan Cheng242ebd12008-09-22 18:19:24 +00003193 N1.getOperand(0).getOpcode() == ISD::AND &&
3194 N1.hasOneUse() && N1.getOperand(0).hasOneUse()) {
Evan Chengeb9f8922008-08-30 02:03:58 +00003195 SDValue N101 = N1.getOperand(0).getOperand(1);
Evan Cheng242ebd12008-09-22 18:19:24 +00003196 if (ConstantSDNode *N101C = dyn_cast<ConstantSDNode>(N101)) {
Owen Andersone50ed302009-08-10 22:56:29 +00003197 EVT TruncVT = N1.getValueType();
Evan Cheng242ebd12008-09-22 18:19:24 +00003198 SDValue N100 = N1.getOperand(0).getOperand(0);
Duncan Sandsb0d5cdd2009-02-01 18:06:53 +00003199 APInt TruncC = N101C->getAPIntValue();
Jay Foad40f8f622010-12-07 08:25:19 +00003200 TruncC = TruncC.trunc(TruncVT.getScalarType().getSizeInBits());
Bill Wendling88103372009-01-30 21:37:17 +00003201 return DAG.getNode(ISD::SRA, N->getDebugLoc(), VT, N0,
Bill Wendling9729c5a2009-01-31 03:12:48 +00003202 DAG.getNode(ISD::AND, N->getDebugLoc(),
Bill Wendling88103372009-01-30 21:37:17 +00003203 TruncVT,
Bill Wendling9729c5a2009-01-31 03:12:48 +00003204 DAG.getNode(ISD::TRUNCATE,
3205 N->getDebugLoc(),
3206 TruncVT, N100),
Dan Gohmance9bc122009-01-27 20:39:34 +00003207 DAG.getConstant(TruncC, TruncVT)));
Evan Chengeb9f8922008-08-30 02:03:58 +00003208 }
3209 }
3210
Benjamin Kramer9b108a32011-01-30 16:38:43 +00003211 // fold (sra (trunc (sr x, c1)), c2) -> (trunc (sra x, c1+c2))
3212 // if c1 is equal to the number of bits the trunc removes
3213 if (N0.getOpcode() == ISD::TRUNCATE &&
3214 (N0.getOperand(0).getOpcode() == ISD::SRL ||
3215 N0.getOperand(0).getOpcode() == ISD::SRA) &&
3216 N0.getOperand(0).hasOneUse() &&
3217 N0.getOperand(0).getOperand(1).hasOneUse() &&
3218 N1C && isa<ConstantSDNode>(N0.getOperand(0).getOperand(1))) {
3219 EVT LargeVT = N0.getOperand(0).getValueType();
3220 ConstantSDNode *LargeShiftAmt =
3221 cast<ConstantSDNode>(N0.getOperand(0).getOperand(1));
3222
3223 if (LargeVT.getScalarType().getSizeInBits() - OpSizeInBits ==
3224 LargeShiftAmt->getZExtValue()) {
3225 SDValue Amt =
3226 DAG.getConstant(LargeShiftAmt->getZExtValue() + N1C->getZExtValue(),
Owen Anderson95771af2011-02-25 21:41:48 +00003227 getShiftAmountTy(N0.getOperand(0).getOperand(0).getValueType()));
Benjamin Kramer9b108a32011-01-30 16:38:43 +00003228 SDValue SRA = DAG.getNode(ISD::SRA, N->getDebugLoc(), LargeVT,
3229 N0.getOperand(0).getOperand(0), Amt);
3230 return DAG.getNode(ISD::TRUNCATE, N->getDebugLoc(), VT, SRA);
3231 }
3232 }
3233
Scott Michelfdc40a02009-02-17 22:15:04 +00003234 // Simplify, based on bits shifted out of the LHS.
Dan Gohman475871a2008-07-27 21:46:04 +00003235 if (N1C && SimplifyDemandedBits(SDValue(N, 0)))
3236 return SDValue(N, 0);
Scott Michelfdc40a02009-02-17 22:15:04 +00003237
3238
Nate Begeman1d4d4142005-09-01 00:19:25 +00003239 // If the sign bit is known to be zero, switch this to a SRL.
Dan Gohman2e68b6f2008-02-25 21:11:39 +00003240 if (DAG.SignBitIsZero(N0))
Bill Wendling88103372009-01-30 21:37:17 +00003241 return DAG.getNode(ISD::SRL, N->getDebugLoc(), VT, N0, N1);
Chris Lattnere70da202007-12-06 07:33:36 +00003242
Evan Chenge5b51ac2010-04-17 06:13:15 +00003243 if (N1C) {
3244 SDValue NewSRA = visitShiftByConstant(N, N1C->getZExtValue());
3245 if (NewSRA.getNode())
3246 return NewSRA;
3247 }
3248
Evan Chengb3a3d5e2010-04-28 07:10:39 +00003249 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00003250}
3251
Dan Gohman475871a2008-07-27 21:46:04 +00003252SDValue DAGCombiner::visitSRL(SDNode *N) {
3253 SDValue N0 = N->getOperand(0);
3254 SDValue N1 = N->getOperand(1);
Nate Begeman646d7e22005-09-02 21:18:40 +00003255 ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0);
3256 ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1);
Owen Andersone50ed302009-08-10 22:56:29 +00003257 EVT VT = N0.getValueType();
Dan Gohman87862e72009-12-11 21:31:27 +00003258 unsigned OpSizeInBits = VT.getScalarType().getSizeInBits();
Scott Michelfdc40a02009-02-17 22:15:04 +00003259
Nate Begeman1d4d4142005-09-01 00:19:25 +00003260 // fold (srl c1, c2) -> c1 >>u c2
Nate Begeman646d7e22005-09-02 21:18:40 +00003261 if (N0C && N1C)
Bill Wendlingf3cbca22008-09-24 10:25:02 +00003262 return DAG.FoldConstantArithmetic(ISD::SRL, VT, N0C, N1C);
Nate Begeman1d4d4142005-09-01 00:19:25 +00003263 // fold (srl 0, x) -> 0
Nate Begeman646d7e22005-09-02 21:18:40 +00003264 if (N0C && N0C->isNullValue())
Nate Begeman83e75ec2005-09-06 04:43:02 +00003265 return N0;
Nate Begeman1d4d4142005-09-01 00:19:25 +00003266 // fold (srl x, c >= size(x)) -> undef
Dan Gohmanf5aeb1a2008-09-12 16:56:44 +00003267 if (N1C && N1C->getZExtValue() >= OpSizeInBits)
Dale Johannesene8d72302009-02-06 23:05:02 +00003268 return DAG.getUNDEF(VT);
Nate Begeman1d4d4142005-09-01 00:19:25 +00003269 // fold (srl x, 0) -> x
Nate Begeman646d7e22005-09-02 21:18:40 +00003270 if (N1C && N1C->isNullValue())
Nate Begeman83e75ec2005-09-06 04:43:02 +00003271 return N0;
Nate Begeman1d4d4142005-09-01 00:19:25 +00003272 // if (srl x, c) is known to be zero, return 0
Dan Gohman475871a2008-07-27 21:46:04 +00003273 if (N1C && DAG.MaskedValueIsZero(SDValue(N, 0),
Dan Gohman2e68b6f2008-02-25 21:11:39 +00003274 APInt::getAllOnesValue(OpSizeInBits)))
Nate Begeman83e75ec2005-09-06 04:43:02 +00003275 return DAG.getConstant(0, VT);
Scott Michelfdc40a02009-02-17 22:15:04 +00003276
Bill Wendling88103372009-01-30 21:37:17 +00003277 // fold (srl (srl x, c1), c2) -> 0 or (srl x, (add c1, c2))
Scott Michelfdc40a02009-02-17 22:15:04 +00003278 if (N1C && N0.getOpcode() == ISD::SRL &&
Nate Begeman1d4d4142005-09-01 00:19:25 +00003279 N0.getOperand(1).getOpcode() == ISD::Constant) {
Dan Gohmanf5aeb1a2008-09-12 16:56:44 +00003280 uint64_t c1 = cast<ConstantSDNode>(N0.getOperand(1))->getZExtValue();
3281 uint64_t c2 = N1C->getZExtValue();
Dale Johannesenc72b18c2010-12-21 21:55:50 +00003282 if (c1 + c2 >= OpSizeInBits)
Nate Begeman83e75ec2005-09-06 04:43:02 +00003283 return DAG.getConstant(0, VT);
Bill Wendling88103372009-01-30 21:37:17 +00003284 return DAG.getNode(ISD::SRL, N->getDebugLoc(), VT, N0.getOperand(0),
Nate Begeman83e75ec2005-09-06 04:43:02 +00003285 DAG.getConstant(c1 + c2, N1.getValueType()));
Nate Begeman1d4d4142005-09-01 00:19:25 +00003286 }
Wesley Peckbf17cfa2010-11-23 03:31:01 +00003287
Dale Johannesenf5daf8b2010-12-17 21:45:49 +00003288 // fold (srl (trunc (srl x, c1)), c2) -> 0 or (trunc (srl x, (add c1, c2)))
Dale Johannesenf5daf8b2010-12-17 21:45:49 +00003289 if (N1C && N0.getOpcode() == ISD::TRUNCATE &&
3290 N0.getOperand(0).getOpcode() == ISD::SRL &&
Dale Johannesen025cc6e2010-12-20 20:10:50 +00003291 isa<ConstantSDNode>(N0.getOperand(0)->getOperand(1))) {
Owen Anderson95771af2011-02-25 21:41:48 +00003292 uint64_t c1 =
Dale Johannesenf5daf8b2010-12-17 21:45:49 +00003293 cast<ConstantSDNode>(N0.getOperand(0)->getOperand(1))->getZExtValue();
3294 uint64_t c2 = N1C->getZExtValue();
Dale Johannesenc72b18c2010-12-21 21:55:50 +00003295 EVT InnerShiftVT = N0.getOperand(0).getValueType();
3296 EVT ShiftCountVT = N0.getOperand(0)->getOperand(1).getValueType();
Dale Johannesenf5daf8b2010-12-17 21:45:49 +00003297 uint64_t InnerShiftSize = InnerShiftVT.getScalarType().getSizeInBits();
Dale Johannesen025cc6e2010-12-20 20:10:50 +00003298 // This is only valid if the OpSizeInBits + c1 = size of inner shift.
Dale Johannesenf5daf8b2010-12-17 21:45:49 +00003299 if (c1 + OpSizeInBits == InnerShiftSize) {
3300 if (c1 + c2 >= InnerShiftSize)
3301 return DAG.getConstant(0, VT);
3302 return DAG.getNode(ISD::TRUNCATE, N0->getDebugLoc(), VT,
Owen Anderson95771af2011-02-25 21:41:48 +00003303 DAG.getNode(ISD::SRL, N0->getDebugLoc(), InnerShiftVT,
Dale Johannesenf5daf8b2010-12-17 21:45:49 +00003304 N0.getOperand(0)->getOperand(0),
Dale Johannesenc72b18c2010-12-21 21:55:50 +00003305 DAG.getConstant(c1 + c2, ShiftCountVT)));
Dale Johannesenf5daf8b2010-12-17 21:45:49 +00003306 }
3307 }
3308
Chris Lattnerefcddc32010-04-15 05:28:43 +00003309 // fold (srl (shl x, c), c) -> (and x, cst2)
3310 if (N1C && N0.getOpcode() == ISD::SHL && N0.getOperand(1) == N1 &&
3311 N0.getValueSizeInBits() <= 64) {
3312 uint64_t ShAmt = N1C->getZExtValue()+64-N0.getValueSizeInBits();
3313 return DAG.getNode(ISD::AND, N->getDebugLoc(), VT, N0.getOperand(0),
3314 DAG.getConstant(~0ULL >> ShAmt, VT));
3315 }
Wesley Peckbf17cfa2010-11-23 03:31:01 +00003316
Scott Michelfdc40a02009-02-17 22:15:04 +00003317
Chris Lattner06afe072006-05-05 22:53:17 +00003318 // fold (srl (anyextend x), c) -> (anyextend (srl x, c))
3319 if (N1C && N0.getOpcode() == ISD::ANY_EXTEND) {
3320 // Shifting in all undef bits?
Owen Andersone50ed302009-08-10 22:56:29 +00003321 EVT SmallVT = N0.getOperand(0).getValueType();
Dan Gohmanf5aeb1a2008-09-12 16:56:44 +00003322 if (N1C->getZExtValue() >= SmallVT.getSizeInBits())
Dale Johannesene8d72302009-02-06 23:05:02 +00003323 return DAG.getUNDEF(VT);
Chris Lattner06afe072006-05-05 22:53:17 +00003324
Evan Chenge5b51ac2010-04-17 06:13:15 +00003325 if (!LegalTypes || TLI.isTypeDesirableForOp(ISD::SRL, SmallVT)) {
Owen Andersona34d9362011-04-14 17:30:49 +00003326 uint64_t ShiftAmt = N1C->getZExtValue();
Evan Chenge5b51ac2010-04-17 06:13:15 +00003327 SDValue SmallShift = DAG.getNode(ISD::SRL, N0.getDebugLoc(), SmallVT,
Owen Andersona34d9362011-04-14 17:30:49 +00003328 N0.getOperand(0),
3329 DAG.getConstant(ShiftAmt, getShiftAmountTy(SmallVT)));
Evan Chenge5b51ac2010-04-17 06:13:15 +00003330 AddToWorkList(SmallShift.getNode());
3331 return DAG.getNode(ISD::ANY_EXTEND, N->getDebugLoc(), VT, SmallShift);
3332 }
Chris Lattner06afe072006-05-05 22:53:17 +00003333 }
Scott Michelfdc40a02009-02-17 22:15:04 +00003334
Chris Lattner3657ffe2006-10-12 20:23:19 +00003335 // fold (srl (sra X, Y), 31) -> (srl X, 31). This srl only looks at the sign
3336 // bit, which is unmodified by sra.
Bill Wendling88103372009-01-30 21:37:17 +00003337 if (N1C && N1C->getZExtValue() + 1 == VT.getSizeInBits()) {
Chris Lattner3657ffe2006-10-12 20:23:19 +00003338 if (N0.getOpcode() == ISD::SRA)
Bill Wendling88103372009-01-30 21:37:17 +00003339 return DAG.getNode(ISD::SRL, N->getDebugLoc(), VT, N0.getOperand(0), N1);
Chris Lattner3657ffe2006-10-12 20:23:19 +00003340 }
Scott Michelfdc40a02009-02-17 22:15:04 +00003341
Chris Lattner350bec02006-04-02 06:11:11 +00003342 // fold (srl (ctlz x), "5") -> x iff x has one bit set (the low bit).
Scott Michelfdc40a02009-02-17 22:15:04 +00003343 if (N1C && N0.getOpcode() == ISD::CTLZ &&
Duncan Sands83ec4b62008-06-06 12:08:01 +00003344 N1C->getAPIntValue() == Log2_32(VT.getSizeInBits())) {
Dan Gohman948d8ea2008-02-20 16:33:30 +00003345 APInt KnownZero, KnownOne;
Dan Gohman5b870af2010-03-02 02:14:38 +00003346 APInt Mask = APInt::getAllOnesValue(VT.getScalarType().getSizeInBits());
Dan Gohmanea859be2007-06-22 14:59:07 +00003347 DAG.ComputeMaskedBits(N0.getOperand(0), Mask, KnownZero, KnownOne);
Scott Michelfdc40a02009-02-17 22:15:04 +00003348
Chris Lattner350bec02006-04-02 06:11:11 +00003349 // If any of the input bits are KnownOne, then the input couldn't be all
3350 // zeros, thus the result of the srl will always be zero.
Dan Gohman948d8ea2008-02-20 16:33:30 +00003351 if (KnownOne.getBoolValue()) return DAG.getConstant(0, VT);
Scott Michelfdc40a02009-02-17 22:15:04 +00003352
Chris Lattner350bec02006-04-02 06:11:11 +00003353 // If all of the bits input the to ctlz node are known to be zero, then
3354 // the result of the ctlz is "32" and the result of the shift is one.
Dan Gohman948d8ea2008-02-20 16:33:30 +00003355 APInt UnknownBits = ~KnownZero & Mask;
Chris Lattner350bec02006-04-02 06:11:11 +00003356 if (UnknownBits == 0) return DAG.getConstant(1, VT);
Scott Michelfdc40a02009-02-17 22:15:04 +00003357
Chris Lattner350bec02006-04-02 06:11:11 +00003358 // Otherwise, check to see if there is exactly one bit input to the ctlz.
Bill Wendling88103372009-01-30 21:37:17 +00003359 if ((UnknownBits & (UnknownBits - 1)) == 0) {
Chris Lattner350bec02006-04-02 06:11:11 +00003360 // Okay, we know that only that the single bit specified by UnknownBits
Bill Wendling88103372009-01-30 21:37:17 +00003361 // could be set on input to the CTLZ node. If this bit is set, the SRL
3362 // will return 0, if it is clear, it returns 1. Change the CTLZ/SRL pair
3363 // to an SRL/XOR pair, which is likely to simplify more.
Dan Gohman948d8ea2008-02-20 16:33:30 +00003364 unsigned ShAmt = UnknownBits.countTrailingZeros();
Dan Gohman475871a2008-07-27 21:46:04 +00003365 SDValue Op = N0.getOperand(0);
Bill Wendling88103372009-01-30 21:37:17 +00003366
Chris Lattner350bec02006-04-02 06:11:11 +00003367 if (ShAmt) {
Bill Wendling88103372009-01-30 21:37:17 +00003368 Op = DAG.getNode(ISD::SRL, N0.getDebugLoc(), VT, Op,
Owen Anderson95771af2011-02-25 21:41:48 +00003369 DAG.getConstant(ShAmt, getShiftAmountTy(Op.getValueType())));
Gabor Greifba36cb52008-08-28 21:40:38 +00003370 AddToWorkList(Op.getNode());
Chris Lattner350bec02006-04-02 06:11:11 +00003371 }
Bill Wendling88103372009-01-30 21:37:17 +00003372
3373 return DAG.getNode(ISD::XOR, N->getDebugLoc(), VT,
3374 Op, DAG.getConstant(1, VT));
Chris Lattner350bec02006-04-02 06:11:11 +00003375 }
3376 }
Evan Chengeb9f8922008-08-30 02:03:58 +00003377
Duncan Sandsb0d5cdd2009-02-01 18:06:53 +00003378 // fold (srl x, (trunc (and y, c))) -> (srl x, (and (trunc y), (trunc c))).
Evan Chengeb9f8922008-08-30 02:03:58 +00003379 if (N1.getOpcode() == ISD::TRUNCATE &&
Evan Cheng242ebd12008-09-22 18:19:24 +00003380 N1.getOperand(0).getOpcode() == ISD::AND &&
3381 N1.hasOneUse() && N1.getOperand(0).hasOneUse()) {
Evan Chengeb9f8922008-08-30 02:03:58 +00003382 SDValue N101 = N1.getOperand(0).getOperand(1);
Evan Cheng242ebd12008-09-22 18:19:24 +00003383 if (ConstantSDNode *N101C = dyn_cast<ConstantSDNode>(N101)) {
Owen Andersone50ed302009-08-10 22:56:29 +00003384 EVT TruncVT = N1.getValueType();
Evan Cheng242ebd12008-09-22 18:19:24 +00003385 SDValue N100 = N1.getOperand(0).getOperand(0);
Duncan Sandsb0d5cdd2009-02-01 18:06:53 +00003386 APInt TruncC = N101C->getAPIntValue();
Jay Foad40f8f622010-12-07 08:25:19 +00003387 TruncC = TruncC.trunc(TruncVT.getSizeInBits());
Bill Wendling88103372009-01-30 21:37:17 +00003388 return DAG.getNode(ISD::SRL, N->getDebugLoc(), VT, N0,
Bill Wendling9729c5a2009-01-31 03:12:48 +00003389 DAG.getNode(ISD::AND, N->getDebugLoc(),
Bill Wendling88103372009-01-30 21:37:17 +00003390 TruncVT,
Bill Wendling9729c5a2009-01-31 03:12:48 +00003391 DAG.getNode(ISD::TRUNCATE,
3392 N->getDebugLoc(),
3393 TruncVT, N100),
Dan Gohmance9bc122009-01-27 20:39:34 +00003394 DAG.getConstant(TruncC, TruncVT)));
Evan Chengeb9f8922008-08-30 02:03:58 +00003395 }
3396 }
Scott Michelfdc40a02009-02-17 22:15:04 +00003397
Chris Lattner61a4c072007-04-18 03:06:49 +00003398 // fold operands of srl based on knowledge that the low bits are not
3399 // demanded.
Dan Gohman475871a2008-07-27 21:46:04 +00003400 if (N1C && SimplifyDemandedBits(SDValue(N, 0)))
3401 return SDValue(N, 0);
Scott Michelfdc40a02009-02-17 22:15:04 +00003402
Evan Cheng9ab2b982009-12-18 21:31:31 +00003403 if (N1C) {
3404 SDValue NewSRL = visitShiftByConstant(N, N1C->getZExtValue());
3405 if (NewSRL.getNode())
3406 return NewSRL;
3407 }
3408
Dan Gohman4e39e9d2010-06-24 14:30:44 +00003409 // Attempt to convert a srl of a load into a narrower zero-extending load.
3410 SDValue NarrowLoad = ReduceLoadWidth(N);
3411 if (NarrowLoad.getNode())
3412 return NarrowLoad;
3413
Evan Cheng9ab2b982009-12-18 21:31:31 +00003414 // Here is a common situation. We want to optimize:
3415 //
3416 // %a = ...
3417 // %b = and i32 %a, 2
3418 // %c = srl i32 %b, 1
3419 // brcond i32 %c ...
3420 //
3421 // into
Wesley Peckbf17cfa2010-11-23 03:31:01 +00003422 //
Evan Cheng9ab2b982009-12-18 21:31:31 +00003423 // %a = ...
3424 // %b = and %a, 2
3425 // %c = setcc eq %b, 0
3426 // brcond %c ...
3427 //
3428 // However when after the source operand of SRL is optimized into AND, the SRL
3429 // itself may not be optimized further. Look for it and add the BRCOND into
3430 // the worklist.
Evan Chengd40d03e2010-01-06 19:38:29 +00003431 if (N->hasOneUse()) {
3432 SDNode *Use = *N->use_begin();
3433 if (Use->getOpcode() == ISD::BRCOND)
3434 AddToWorkList(Use);
3435 else if (Use->getOpcode() == ISD::TRUNCATE && Use->hasOneUse()) {
3436 // Also look pass the truncate.
3437 Use = *Use->use_begin();
3438 if (Use->getOpcode() == ISD::BRCOND)
3439 AddToWorkList(Use);
3440 }
3441 }
Evan Cheng9ab2b982009-12-18 21:31:31 +00003442
Evan Chengb3a3d5e2010-04-28 07:10:39 +00003443 return SDValue();
Evan Cheng4c26e932010-04-19 19:29:22 +00003444}
3445
Dan Gohman475871a2008-07-27 21:46:04 +00003446SDValue DAGCombiner::visitCTLZ(SDNode *N) {
3447 SDValue N0 = N->getOperand(0);
Owen Andersone50ed302009-08-10 22:56:29 +00003448 EVT VT = N->getValueType(0);
Nate Begeman1d4d4142005-09-01 00:19:25 +00003449
3450 // fold (ctlz c1) -> c2
Chris Lattner310b5782006-05-06 23:06:26 +00003451 if (isa<ConstantSDNode>(N0))
Bill Wendling34584e62009-01-30 22:02:18 +00003452 return DAG.getNode(ISD::CTLZ, N->getDebugLoc(), VT, N0);
Dan Gohman475871a2008-07-27 21:46:04 +00003453 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00003454}
3455
Dan Gohman475871a2008-07-27 21:46:04 +00003456SDValue DAGCombiner::visitCTTZ(SDNode *N) {
3457 SDValue N0 = N->getOperand(0);
Owen Andersone50ed302009-08-10 22:56:29 +00003458 EVT VT = N->getValueType(0);
Scott Michelfdc40a02009-02-17 22:15:04 +00003459
Nate Begeman1d4d4142005-09-01 00:19:25 +00003460 // fold (cttz c1) -> c2
Chris Lattner310b5782006-05-06 23:06:26 +00003461 if (isa<ConstantSDNode>(N0))
Bill Wendling34584e62009-01-30 22:02:18 +00003462 return DAG.getNode(ISD::CTTZ, N->getDebugLoc(), VT, N0);
Dan Gohman475871a2008-07-27 21:46:04 +00003463 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00003464}
3465
Dan Gohman475871a2008-07-27 21:46:04 +00003466SDValue DAGCombiner::visitCTPOP(SDNode *N) {
3467 SDValue N0 = N->getOperand(0);
Owen Andersone50ed302009-08-10 22:56:29 +00003468 EVT VT = N->getValueType(0);
Scott Michelfdc40a02009-02-17 22:15:04 +00003469
Nate Begeman1d4d4142005-09-01 00:19:25 +00003470 // fold (ctpop c1) -> c2
Chris Lattner310b5782006-05-06 23:06:26 +00003471 if (isa<ConstantSDNode>(N0))
Bill Wendling34584e62009-01-30 22:02:18 +00003472 return DAG.getNode(ISD::CTPOP, N->getDebugLoc(), VT, N0);
Dan Gohman475871a2008-07-27 21:46:04 +00003473 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00003474}
3475
Dan Gohman475871a2008-07-27 21:46:04 +00003476SDValue DAGCombiner::visitSELECT(SDNode *N) {
3477 SDValue N0 = N->getOperand(0);
3478 SDValue N1 = N->getOperand(1);
3479 SDValue N2 = N->getOperand(2);
Nate Begeman452d7beb2005-09-16 00:54:12 +00003480 ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0);
3481 ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1);
3482 ConstantSDNode *N2C = dyn_cast<ConstantSDNode>(N2);
Owen Andersone50ed302009-08-10 22:56:29 +00003483 EVT VT = N->getValueType(0);
3484 EVT VT0 = N0.getValueType();
Nate Begeman44728a72005-09-19 22:34:01 +00003485
Bill Wendling34584e62009-01-30 22:02:18 +00003486 // fold (select C, X, X) -> X
Nate Begeman452d7beb2005-09-16 00:54:12 +00003487 if (N1 == N2)
3488 return N1;
Bill Wendling34584e62009-01-30 22:02:18 +00003489 // fold (select true, X, Y) -> X
Nate Begeman452d7beb2005-09-16 00:54:12 +00003490 if (N0C && !N0C->isNullValue())
3491 return N1;
Bill Wendling34584e62009-01-30 22:02:18 +00003492 // fold (select false, X, Y) -> Y
Nate Begeman452d7beb2005-09-16 00:54:12 +00003493 if (N0C && N0C->isNullValue())
3494 return N2;
Bill Wendling34584e62009-01-30 22:02:18 +00003495 // fold (select C, 1, X) -> (or C, X)
Owen Anderson825b72b2009-08-11 20:47:22 +00003496 if (VT == MVT::i1 && N1C && N1C->getAPIntValue() == 1)
Bill Wendling34584e62009-01-30 22:02:18 +00003497 return DAG.getNode(ISD::OR, N->getDebugLoc(), VT, N0, N2);
3498 // fold (select C, 0, 1) -> (xor C, 1)
Bob Wilson67ba2232009-01-22 22:05:48 +00003499 if (VT.isInteger() &&
Owen Anderson825b72b2009-08-11 20:47:22 +00003500 (VT0 == MVT::i1 ||
Bob Wilson67ba2232009-01-22 22:05:48 +00003501 (VT0.isInteger() &&
3502 TLI.getBooleanContents() == TargetLowering::ZeroOrOneBooleanContent)) &&
Dan Gohman002e5d02008-03-13 22:13:53 +00003503 N1C && N2C && N1C->isNullValue() && N2C->getAPIntValue() == 1) {
Bill Wendling34584e62009-01-30 22:02:18 +00003504 SDValue XORNode;
Evan Cheng571c4782007-08-18 05:57:05 +00003505 if (VT == VT0)
Bill Wendling34584e62009-01-30 22:02:18 +00003506 return DAG.getNode(ISD::XOR, N->getDebugLoc(), VT0,
3507 N0, DAG.getConstant(1, VT0));
3508 XORNode = DAG.getNode(ISD::XOR, N0.getDebugLoc(), VT0,
3509 N0, DAG.getConstant(1, VT0));
Gabor Greifba36cb52008-08-28 21:40:38 +00003510 AddToWorkList(XORNode.getNode());
Duncan Sands8e4eb092008-06-08 20:54:56 +00003511 if (VT.bitsGT(VT0))
Bill Wendling34584e62009-01-30 22:02:18 +00003512 return DAG.getNode(ISD::ZERO_EXTEND, N->getDebugLoc(), VT, XORNode);
3513 return DAG.getNode(ISD::TRUNCATE, N->getDebugLoc(), VT, XORNode);
Evan Cheng571c4782007-08-18 05:57:05 +00003514 }
Bill Wendling34584e62009-01-30 22:02:18 +00003515 // fold (select C, 0, X) -> (and (not C), X)
Owen Anderson825b72b2009-08-11 20:47:22 +00003516 if (VT == VT0 && VT == MVT::i1 && N1C && N1C->isNullValue()) {
Bill Wendling7581bfa2009-01-30 23:03:19 +00003517 SDValue NOTNode = DAG.getNOT(N0.getDebugLoc(), N0, VT);
Bob Wilson4c245462009-01-22 17:39:32 +00003518 AddToWorkList(NOTNode.getNode());
Bill Wendling7581bfa2009-01-30 23:03:19 +00003519 return DAG.getNode(ISD::AND, N->getDebugLoc(), VT, NOTNode, N2);
Nate Begeman452d7beb2005-09-16 00:54:12 +00003520 }
Bill Wendling34584e62009-01-30 22:02:18 +00003521 // fold (select C, X, 1) -> (or (not C), X)
Owen Anderson825b72b2009-08-11 20:47:22 +00003522 if (VT == VT0 && VT == MVT::i1 && N2C && N2C->getAPIntValue() == 1) {
Bill Wendling34584e62009-01-30 22:02:18 +00003523 SDValue NOTNode = DAG.getNOT(N0.getDebugLoc(), N0, VT);
Bob Wilson4c245462009-01-22 17:39:32 +00003524 AddToWorkList(NOTNode.getNode());
Bill Wendling7581bfa2009-01-30 23:03:19 +00003525 return DAG.getNode(ISD::OR, N->getDebugLoc(), VT, NOTNode, N1);
Nate Begeman452d7beb2005-09-16 00:54:12 +00003526 }
Bill Wendling34584e62009-01-30 22:02:18 +00003527 // fold (select C, X, 0) -> (and C, X)
Owen Anderson825b72b2009-08-11 20:47:22 +00003528 if (VT == MVT::i1 && N2C && N2C->isNullValue())
Bill Wendling34584e62009-01-30 22:02:18 +00003529 return DAG.getNode(ISD::AND, N->getDebugLoc(), VT, N0, N1);
3530 // fold (select X, X, Y) -> (or X, Y)
3531 // fold (select X, 1, Y) -> (or X, Y)
Owen Anderson825b72b2009-08-11 20:47:22 +00003532 if (VT == MVT::i1 && (N0 == N1 || (N1C && N1C->getAPIntValue() == 1)))
Bill Wendling34584e62009-01-30 22:02:18 +00003533 return DAG.getNode(ISD::OR, N->getDebugLoc(), VT, N0, N2);
3534 // fold (select X, Y, X) -> (and X, Y)
3535 // fold (select X, Y, 0) -> (and X, Y)
Owen Anderson825b72b2009-08-11 20:47:22 +00003536 if (VT == MVT::i1 && (N0 == N2 || (N2C && N2C->getAPIntValue() == 0)))
Bill Wendling34584e62009-01-30 22:02:18 +00003537 return DAG.getNode(ISD::AND, N->getDebugLoc(), VT, N0, N1);
Scott Michelfdc40a02009-02-17 22:15:04 +00003538
Chris Lattner40c62d52005-10-18 06:04:22 +00003539 // If we can fold this based on the true/false value, do so.
3540 if (SimplifySelectOps(N, N1, N2))
Dan Gohman475871a2008-07-27 21:46:04 +00003541 return SDValue(N, 0); // Don't revisit N.
Duncan Sandsd4b9c172008-06-13 19:07:40 +00003542
Nate Begeman44728a72005-09-19 22:34:01 +00003543 // fold selects based on a setcc into other things, such as min/max/abs
Anton Korobeynikov4c71dfe2008-02-20 11:10:28 +00003544 if (N0.getOpcode() == ISD::SETCC) {
Nate Begeman750ac1b2006-02-01 07:19:44 +00003545 // FIXME:
Owen Anderson825b72b2009-08-11 20:47:22 +00003546 // Check against MVT::Other for SELECT_CC, which is a workaround for targets
Nate Begeman750ac1b2006-02-01 07:19:44 +00003547 // having to say they don't support SELECT_CC on every type the DAG knows
3548 // about, since there is no way to mark an opcode illegal at all value types
Owen Anderson825b72b2009-08-11 20:47:22 +00003549 if (TLI.isOperationLegalOrCustom(ISD::SELECT_CC, MVT::Other) &&
Dan Gohman4ea48042009-08-02 16:19:38 +00003550 TLI.isOperationLegalOrCustom(ISD::SELECT_CC, VT))
Bill Wendling34584e62009-01-30 22:02:18 +00003551 return DAG.getNode(ISD::SELECT_CC, N->getDebugLoc(), VT,
3552 N0.getOperand(0), N0.getOperand(1),
Nate Begeman750ac1b2006-02-01 07:19:44 +00003553 N1, N2, N0.getOperand(2));
Chris Lattner600fec32009-03-11 05:08:08 +00003554 return SimplifySelect(N->getDebugLoc(), N0, N1, N2);
Anton Korobeynikov4c71dfe2008-02-20 11:10:28 +00003555 }
Bill Wendling34584e62009-01-30 22:02:18 +00003556
Dan Gohman475871a2008-07-27 21:46:04 +00003557 return SDValue();
Nate Begeman452d7beb2005-09-16 00:54:12 +00003558}
3559
Dan Gohman475871a2008-07-27 21:46:04 +00003560SDValue DAGCombiner::visitSELECT_CC(SDNode *N) {
3561 SDValue N0 = N->getOperand(0);
3562 SDValue N1 = N->getOperand(1);
3563 SDValue N2 = N->getOperand(2);
3564 SDValue N3 = N->getOperand(3);
3565 SDValue N4 = N->getOperand(4);
Nate Begeman44728a72005-09-19 22:34:01 +00003566 ISD::CondCode CC = cast<CondCodeSDNode>(N4)->get();
Scott Michelfdc40a02009-02-17 22:15:04 +00003567
Nate Begeman44728a72005-09-19 22:34:01 +00003568 // fold select_cc lhs, rhs, x, x, cc -> x
3569 if (N2 == N3)
3570 return N2;
Scott Michelfdc40a02009-02-17 22:15:04 +00003571
Chris Lattner5f42a242006-09-20 06:19:26 +00003572 // Determine if the condition we're dealing with is constant
Duncan Sands5480c042009-01-01 15:52:00 +00003573 SDValue SCC = SimplifySetCC(TLI.getSetCCResultType(N0.getValueType()),
Dale Johannesenff97d4f2009-02-03 00:47:48 +00003574 N0, N1, CC, N->getDebugLoc(), false);
Gabor Greifba36cb52008-08-28 21:40:38 +00003575 if (SCC.getNode()) AddToWorkList(SCC.getNode());
Chris Lattner5f42a242006-09-20 06:19:26 +00003576
Gabor Greifba36cb52008-08-28 21:40:38 +00003577 if (ConstantSDNode *SCCC = dyn_cast_or_null<ConstantSDNode>(SCC.getNode())) {
Dan Gohman002e5d02008-03-13 22:13:53 +00003578 if (!SCCC->isNullValue())
Chris Lattner5f42a242006-09-20 06:19:26 +00003579 return N2; // cond always true -> true val
3580 else
3581 return N3; // cond always false -> false val
3582 }
Scott Michelfdc40a02009-02-17 22:15:04 +00003583
Chris Lattner5f42a242006-09-20 06:19:26 +00003584 // Fold to a simpler select_cc
Gabor Greifba36cb52008-08-28 21:40:38 +00003585 if (SCC.getNode() && SCC.getOpcode() == ISD::SETCC)
Scott Michelfdc40a02009-02-17 22:15:04 +00003586 return DAG.getNode(ISD::SELECT_CC, N->getDebugLoc(), N2.getValueType(),
3587 SCC.getOperand(0), SCC.getOperand(1), N2, N3,
Chris Lattner5f42a242006-09-20 06:19:26 +00003588 SCC.getOperand(2));
Scott Michelfdc40a02009-02-17 22:15:04 +00003589
Chris Lattner40c62d52005-10-18 06:04:22 +00003590 // If we can fold this based on the true/false value, do so.
3591 if (SimplifySelectOps(N, N2, N3))
Dan Gohman475871a2008-07-27 21:46:04 +00003592 return SDValue(N, 0); // Don't revisit N.
Scott Michelfdc40a02009-02-17 22:15:04 +00003593
Nate Begeman44728a72005-09-19 22:34:01 +00003594 // fold select_cc into other things, such as min/max/abs
Bill Wendling836ca7d2009-01-30 23:59:18 +00003595 return SimplifySelectCC(N->getDebugLoc(), N0, N1, N2, N3, CC);
Nate Begeman452d7beb2005-09-16 00:54:12 +00003596}
3597
Dan Gohman475871a2008-07-27 21:46:04 +00003598SDValue DAGCombiner::visitSETCC(SDNode *N) {
Nate Begeman452d7beb2005-09-16 00:54:12 +00003599 return SimplifySetCC(N->getValueType(0), N->getOperand(0), N->getOperand(1),
Dale Johannesenff97d4f2009-02-03 00:47:48 +00003600 cast<CondCodeSDNode>(N->getOperand(2))->get(),
3601 N->getDebugLoc());
Nate Begeman452d7beb2005-09-16 00:54:12 +00003602}
3603
Evan Cheng3c3ddb32007-10-29 19:58:20 +00003604// ExtendUsesToFormExtLoad - Trying to extend uses of a load to enable this:
Dan Gohman57fc82d2009-04-09 03:51:29 +00003605// "fold ({s|z|a}ext (load x)) -> ({s|z|a}ext (truncate ({s|z|a}extload x)))"
Evan Cheng3c3ddb32007-10-29 19:58:20 +00003606// transformation. Returns true if extension are possible and the above
Scott Michelfdc40a02009-02-17 22:15:04 +00003607// mentioned transformation is profitable.
Dan Gohman475871a2008-07-27 21:46:04 +00003608static bool ExtendUsesToFormExtLoad(SDNode *N, SDValue N0,
Evan Cheng3c3ddb32007-10-29 19:58:20 +00003609 unsigned ExtOpc,
3610 SmallVector<SDNode*, 4> &ExtendNodes,
Dan Gohman79ce2762009-01-15 19:20:50 +00003611 const TargetLowering &TLI) {
Evan Cheng3c3ddb32007-10-29 19:58:20 +00003612 bool HasCopyToRegUses = false;
3613 bool isTruncFree = TLI.isTruncateFree(N->getValueType(0), N0.getValueType());
Gabor Greif12632d22008-08-30 19:29:20 +00003614 for (SDNode::use_iterator UI = N0.getNode()->use_begin(),
3615 UE = N0.getNode()->use_end();
Evan Cheng3c3ddb32007-10-29 19:58:20 +00003616 UI != UE; ++UI) {
Dan Gohman89684502008-07-27 20:43:25 +00003617 SDNode *User = *UI;
Evan Cheng3c3ddb32007-10-29 19:58:20 +00003618 if (User == N)
3619 continue;
Dan Gohman57fc82d2009-04-09 03:51:29 +00003620 if (UI.getUse().getResNo() != N0.getResNo())
3621 continue;
Evan Cheng3c3ddb32007-10-29 19:58:20 +00003622 // FIXME: Only extend SETCC N, N and SETCC N, c for now.
Dan Gohman57fc82d2009-04-09 03:51:29 +00003623 if (ExtOpc != ISD::ANY_EXTEND && User->getOpcode() == ISD::SETCC) {
Evan Cheng3c3ddb32007-10-29 19:58:20 +00003624 ISD::CondCode CC = cast<CondCodeSDNode>(User->getOperand(2))->get();
3625 if (ExtOpc == ISD::ZERO_EXTEND && ISD::isSignedIntSetCC(CC))
3626 // Sign bits will be lost after a zext.
3627 return false;
3628 bool Add = false;
3629 for (unsigned i = 0; i != 2; ++i) {
Dan Gohman475871a2008-07-27 21:46:04 +00003630 SDValue UseOp = User->getOperand(i);
Evan Cheng3c3ddb32007-10-29 19:58:20 +00003631 if (UseOp == N0)
3632 continue;
3633 if (!isa<ConstantSDNode>(UseOp))
3634 return false;
3635 Add = true;
3636 }
3637 if (Add)
3638 ExtendNodes.push_back(User);
Dan Gohman57fc82d2009-04-09 03:51:29 +00003639 continue;
Evan Cheng3c3ddb32007-10-29 19:58:20 +00003640 }
Dan Gohman57fc82d2009-04-09 03:51:29 +00003641 // If truncates aren't free and there are users we can't
3642 // extend, it isn't worthwhile.
3643 if (!isTruncFree)
3644 return false;
3645 // Remember if this value is live-out.
3646 if (User->getOpcode() == ISD::CopyToReg)
3647 HasCopyToRegUses = true;
Evan Cheng3c3ddb32007-10-29 19:58:20 +00003648 }
3649
3650 if (HasCopyToRegUses) {
3651 bool BothLiveOut = false;
3652 for (SDNode::use_iterator UI = N->use_begin(), UE = N->use_end();
3653 UI != UE; ++UI) {
Dan Gohman57fc82d2009-04-09 03:51:29 +00003654 SDUse &Use = UI.getUse();
3655 if (Use.getResNo() == 0 && Use.getUser()->getOpcode() == ISD::CopyToReg) {
3656 BothLiveOut = true;
3657 break;
Evan Cheng3c3ddb32007-10-29 19:58:20 +00003658 }
3659 }
3660 if (BothLiveOut)
3661 // Both unextended and extended values are live out. There had better be
Bob Wilsonbebfbc52010-11-28 06:51:19 +00003662 // a good reason for the transformation.
Evan Cheng3c3ddb32007-10-29 19:58:20 +00003663 return ExtendNodes.size();
3664 }
3665 return true;
3666}
3667
Dan Gohman475871a2008-07-27 21:46:04 +00003668SDValue DAGCombiner::visitSIGN_EXTEND(SDNode *N) {
3669 SDValue N0 = N->getOperand(0);
Owen Andersone50ed302009-08-10 22:56:29 +00003670 EVT VT = N->getValueType(0);
Nate Begeman1d4d4142005-09-01 00:19:25 +00003671
Nate Begeman1d4d4142005-09-01 00:19:25 +00003672 // fold (sext c1) -> c1
Reid Spencer3ed469c2006-11-02 20:25:50 +00003673 if (isa<ConstantSDNode>(N0))
Bill Wendling6ce610f2009-01-30 22:23:15 +00003674 return DAG.getNode(ISD::SIGN_EXTEND, N->getDebugLoc(), VT, N0);
Scott Michelfdc40a02009-02-17 22:15:04 +00003675
Nate Begeman1d4d4142005-09-01 00:19:25 +00003676 // fold (sext (sext x)) -> (sext x)
Chris Lattner310b5782006-05-06 23:06:26 +00003677 // fold (sext (aext x)) -> (sext x)
3678 if (N0.getOpcode() == ISD::SIGN_EXTEND || N0.getOpcode() == ISD::ANY_EXTEND)
Bill Wendling6ce610f2009-01-30 22:23:15 +00003679 return DAG.getNode(ISD::SIGN_EXTEND, N->getDebugLoc(), VT,
3680 N0.getOperand(0));
Scott Michelfdc40a02009-02-17 22:15:04 +00003681
Chris Lattner22558872007-02-26 03:13:59 +00003682 if (N0.getOpcode() == ISD::TRUNCATE) {
Dan Gohman1fdfa6a2008-05-20 20:56:33 +00003683 // fold (sext (truncate (load x))) -> (sext (smaller load x))
3684 // fold (sext (truncate (srl (load x), c))) -> (sext (smaller load (x+c/n)))
Gabor Greifba36cb52008-08-28 21:40:38 +00003685 SDValue NarrowLoad = ReduceLoadWidth(N0.getNode());
3686 if (NarrowLoad.getNode()) {
Dale Johannesen61734eb2010-05-25 17:50:03 +00003687 SDNode* oye = N0.getNode()->getOperand(0).getNode();
3688 if (NarrowLoad.getNode() != N0.getNode()) {
Gabor Greifba36cb52008-08-28 21:40:38 +00003689 CombineTo(N0.getNode(), NarrowLoad);
Dale Johannesen61734eb2010-05-25 17:50:03 +00003690 // CombineTo deleted the truncate, if needed, but not what's under it.
3691 AddToWorkList(oye);
3692 }
Dan Gohmanc7b34442009-04-27 02:00:55 +00003693 return SDValue(N, 0); // Return N so it doesn't get rechecked!
Evan Cheng0b063de2007-03-23 02:16:52 +00003694 }
Evan Chengc88138f2007-03-22 01:54:19 +00003695
Dan Gohman1fdfa6a2008-05-20 20:56:33 +00003696 // See if the value being truncated is already sign extended. If so, just
3697 // eliminate the trunc/sext pair.
Dan Gohman475871a2008-07-27 21:46:04 +00003698 SDValue Op = N0.getOperand(0);
Dan Gohmand1996362010-01-09 02:13:55 +00003699 unsigned OpBits = Op.getValueType().getScalarType().getSizeInBits();
3700 unsigned MidBits = N0.getValueType().getScalarType().getSizeInBits();
3701 unsigned DestBits = VT.getScalarType().getSizeInBits();
Dan Gohmanea859be2007-06-22 14:59:07 +00003702 unsigned NumSignBits = DAG.ComputeNumSignBits(Op);
Scott Michelfdc40a02009-02-17 22:15:04 +00003703
Chris Lattner22558872007-02-26 03:13:59 +00003704 if (OpBits == DestBits) {
3705 // Op is i32, Mid is i8, and Dest is i32. If Op has more than 24 sign
3706 // bits, it is already ready.
3707 if (NumSignBits > DestBits-MidBits)
3708 return Op;
3709 } else if (OpBits < DestBits) {
3710 // Op is i32, Mid is i8, and Dest is i64. If Op has more than 24 sign
3711 // bits, just sext from i32.
3712 if (NumSignBits > OpBits-MidBits)
Bill Wendling6ce610f2009-01-30 22:23:15 +00003713 return DAG.getNode(ISD::SIGN_EXTEND, N->getDebugLoc(), VT, Op);
Chris Lattner22558872007-02-26 03:13:59 +00003714 } else {
3715 // Op is i64, Mid is i8, and Dest is i32. If Op has more than 56 sign
3716 // bits, just truncate to i32.
3717 if (NumSignBits > OpBits-MidBits)
Bill Wendling6ce610f2009-01-30 22:23:15 +00003718 return DAG.getNode(ISD::TRUNCATE, N->getDebugLoc(), VT, Op);
Chris Lattner6007b842006-09-21 06:00:20 +00003719 }
Scott Michelfdc40a02009-02-17 22:15:04 +00003720
Chris Lattner22558872007-02-26 03:13:59 +00003721 // fold (sext (truncate x)) -> (sextinreg x).
Duncan Sands25cf2272008-11-24 14:53:14 +00003722 if (!LegalOperations || TLI.isOperationLegal(ISD::SIGN_EXTEND_INREG,
3723 N0.getValueType())) {
Dan Gohmand1996362010-01-09 02:13:55 +00003724 if (OpBits < DestBits)
Bill Wendling6ce610f2009-01-30 22:23:15 +00003725 Op = DAG.getNode(ISD::ANY_EXTEND, N0.getDebugLoc(), VT, Op);
Dan Gohmand1996362010-01-09 02:13:55 +00003726 else if (OpBits > DestBits)
Bill Wendling6ce610f2009-01-30 22:23:15 +00003727 Op = DAG.getNode(ISD::TRUNCATE, N0.getDebugLoc(), VT, Op);
3728 return DAG.getNode(ISD::SIGN_EXTEND_INREG, N->getDebugLoc(), VT, Op,
Dan Gohmand1996362010-01-09 02:13:55 +00003729 DAG.getValueType(N0.getValueType()));
Chris Lattner22558872007-02-26 03:13:59 +00003730 }
Chris Lattner6007b842006-09-21 06:00:20 +00003731 }
Scott Michelfdc40a02009-02-17 22:15:04 +00003732
Evan Cheng110dec22005-12-14 02:19:23 +00003733 // fold (sext (load x)) -> (sext (truncate (sextload x)))
Nadav Rotem8c20ec52011-02-24 21:01:34 +00003734 // None of the supported targets knows how to perform load and sign extend
Nadav Rotemfcd96192011-02-27 07:40:43 +00003735 // on vectors in one instruction. We only perform this transformation on
3736 // scalars.
Nadav Rotem8c20ec52011-02-24 21:01:34 +00003737 if (ISD::isNON_EXTLoad(N0.getNode()) && !VT.isVector() &&
Duncan Sands25cf2272008-11-24 14:53:14 +00003738 ((!LegalOperations && !cast<LoadSDNode>(N0)->isVolatile()) ||
Evan Cheng03294662008-10-14 21:26:46 +00003739 TLI.isLoadExtLegal(ISD::SEXTLOAD, N0.getValueType()))) {
Evan Cheng3c3ddb32007-10-29 19:58:20 +00003740 bool DoXform = true;
3741 SmallVector<SDNode*, 4> SetCCs;
3742 if (!N0.hasOneUse())
3743 DoXform = ExtendUsesToFormExtLoad(N, N0, ISD::SIGN_EXTEND, SetCCs, TLI);
3744 if (DoXform) {
3745 LoadSDNode *LN0 = cast<LoadSDNode>(N0);
Stuart Hastingsa9011292011-02-16 16:23:55 +00003746 SDValue ExtLoad = DAG.getExtLoad(ISD::SEXTLOAD, N->getDebugLoc(), VT,
Dan Gohman57fc82d2009-04-09 03:51:29 +00003747 LN0->getChain(),
Chris Lattner3d6ccfb2010-09-21 17:04:51 +00003748 LN0->getBasePtr(), LN0->getPointerInfo(),
Duncan Sands25cf2272008-11-24 14:53:14 +00003749 N0.getValueType(),
David Greene1e559442010-02-15 17:00:31 +00003750 LN0->isVolatile(), LN0->isNonTemporal(),
3751 LN0->getAlignment());
Evan Cheng3c3ddb32007-10-29 19:58:20 +00003752 CombineTo(N, ExtLoad);
Bill Wendling6ce610f2009-01-30 22:23:15 +00003753 SDValue Trunc = DAG.getNode(ISD::TRUNCATE, N0.getDebugLoc(),
3754 N0.getValueType(), ExtLoad);
Gabor Greifba36cb52008-08-28 21:40:38 +00003755 CombineTo(N0.getNode(), Trunc, ExtLoad.getValue(1));
Bill Wendling6ce610f2009-01-30 22:23:15 +00003756
Evan Cheng3c3ddb32007-10-29 19:58:20 +00003757 // Extend SetCC uses if necessary.
3758 for (unsigned i = 0, e = SetCCs.size(); i != e; ++i) {
3759 SDNode *SetCC = SetCCs[i];
Dan Gohman475871a2008-07-27 21:46:04 +00003760 SmallVector<SDValue, 4> Ops;
Bill Wendling6ce610f2009-01-30 22:23:15 +00003761
Evan Cheng3c3ddb32007-10-29 19:58:20 +00003762 for (unsigned j = 0; j != 2; ++j) {
Dan Gohman475871a2008-07-27 21:46:04 +00003763 SDValue SOp = SetCC->getOperand(j);
Evan Cheng3c3ddb32007-10-29 19:58:20 +00003764 if (SOp == Trunc)
3765 Ops.push_back(ExtLoad);
3766 else
Dan Gohman57fc82d2009-04-09 03:51:29 +00003767 Ops.push_back(DAG.getNode(ISD::SIGN_EXTEND,
3768 N->getDebugLoc(), VT, SOp));
Bill Wendling6ce610f2009-01-30 22:23:15 +00003769 }
3770
Evan Cheng3c3ddb32007-10-29 19:58:20 +00003771 Ops.push_back(SetCC->getOperand(2));
Bill Wendling9729c5a2009-01-31 03:12:48 +00003772 CombineTo(SetCC, DAG.getNode(ISD::SETCC, N->getDebugLoc(),
Bill Wendling6ce610f2009-01-30 22:23:15 +00003773 SetCC->getValueType(0),
Evan Cheng3c3ddb32007-10-29 19:58:20 +00003774 &Ops[0], Ops.size()));
3775 }
Bill Wendling6ce610f2009-01-30 22:23:15 +00003776
Dan Gohman475871a2008-07-27 21:46:04 +00003777 return SDValue(N, 0); // Return N so it doesn't get rechecked!
Evan Cheng3c3ddb32007-10-29 19:58:20 +00003778 }
Nate Begeman3df4d522005-10-12 20:40:40 +00003779 }
Chris Lattnerad25d4e2005-12-14 19:05:06 +00003780
3781 // fold (sext (sextload x)) -> (sext (truncate (sextload x)))
3782 // fold (sext ( extload x)) -> (sext (truncate (sextload x)))
Gabor Greifba36cb52008-08-28 21:40:38 +00003783 if ((ISD::isSEXTLoad(N0.getNode()) || ISD::isEXTLoad(N0.getNode())) &&
3784 ISD::isUNINDEXEDLoad(N0.getNode()) && N0.hasOneUse()) {
Evan Cheng466685d2006-10-09 20:57:25 +00003785 LoadSDNode *LN0 = cast<LoadSDNode>(N0);
Dan Gohman8a55ce42009-09-23 21:02:20 +00003786 EVT MemVT = LN0->getMemoryVT();
Duncan Sands25cf2272008-11-24 14:53:14 +00003787 if ((!LegalOperations && !LN0->isVolatile()) ||
Dan Gohman8a55ce42009-09-23 21:02:20 +00003788 TLI.isLoadExtLegal(ISD::SEXTLOAD, MemVT)) {
Stuart Hastingsa9011292011-02-16 16:23:55 +00003789 SDValue ExtLoad = DAG.getExtLoad(ISD::SEXTLOAD, N->getDebugLoc(), VT,
Bill Wendling6ce610f2009-01-30 22:23:15 +00003790 LN0->getChain(),
Chris Lattner3d6ccfb2010-09-21 17:04:51 +00003791 LN0->getBasePtr(), LN0->getPointerInfo(),
3792 MemVT,
David Greene1e559442010-02-15 17:00:31 +00003793 LN0->isVolatile(), LN0->isNonTemporal(),
3794 LN0->getAlignment());
Jim Laskeyf6c4ccf2006-12-15 21:38:30 +00003795 CombineTo(N, ExtLoad);
Gabor Greif12632d22008-08-30 19:29:20 +00003796 CombineTo(N0.getNode(),
Bill Wendling6ce610f2009-01-30 22:23:15 +00003797 DAG.getNode(ISD::TRUNCATE, N0.getDebugLoc(),
3798 N0.getValueType(), ExtLoad),
Jim Laskeyf6c4ccf2006-12-15 21:38:30 +00003799 ExtLoad.getValue(1));
Dan Gohman475871a2008-07-27 21:46:04 +00003800 return SDValue(N, 0); // Return N so it doesn't get rechecked!
Jim Laskeyf6c4ccf2006-12-15 21:38:30 +00003801 }
Chris Lattnerad25d4e2005-12-14 19:05:06 +00003802 }
Scott Michelfdc40a02009-02-17 22:15:04 +00003803
Chris Lattner20a35c32007-04-11 05:32:27 +00003804 if (N0.getOpcode() == ISD::SETCC) {
Chris Lattner2b7a2712009-07-08 00:31:33 +00003805 // sext(setcc) -> sext_in_reg(vsetcc) for vectors.
Dan Gohman3ce89f42010-04-30 17:19:19 +00003806 // Only do this before legalize for now.
3807 if (VT.isVector() && !LegalOperations) {
3808 EVT N0VT = N0.getOperand(0).getValueType();
Chris Lattner2b7a2712009-07-08 00:31:33 +00003809 // We know that the # elements of the results is the same as the
3810 // # elements of the compare (and the # elements of the compare result
3811 // for that matter). Check to see that they are the same size. If so,
3812 // we know that the element size of the sext'd result matches the
3813 // element size of the compare operands.
Dan Gohman3ce89f42010-04-30 17:19:19 +00003814 if (VT.getSizeInBits() == N0VT.getSizeInBits())
Duncan Sands34727662010-07-12 08:16:59 +00003815 return DAG.getVSetCC(N->getDebugLoc(), VT, N0.getOperand(0),
3816 N0.getOperand(1),
3817 cast<CondCodeSDNode>(N0.getOperand(2))->get());
Dan Gohman3ce89f42010-04-30 17:19:19 +00003818 // If the desired elements are smaller or larger than the source
3819 // elements we can use a matching integer vector type and then
3820 // truncate/sign extend
3821 else {
Duncan Sands34727662010-07-12 08:16:59 +00003822 EVT MatchingElementType =
3823 EVT::getIntegerVT(*DAG.getContext(),
3824 N0VT.getScalarType().getSizeInBits());
3825 EVT MatchingVectorType =
3826 EVT::getVectorVT(*DAG.getContext(), MatchingElementType,
3827 N0VT.getVectorNumElements());
3828 SDValue VsetCC =
3829 DAG.getVSetCC(N->getDebugLoc(), MatchingVectorType, N0.getOperand(0),
3830 N0.getOperand(1),
3831 cast<CondCodeSDNode>(N0.getOperand(2))->get());
3832 return DAG.getSExtOrTrunc(VsetCC, N->getDebugLoc(), VT);
Dan Gohman3ce89f42010-04-30 17:19:19 +00003833 }
Chris Lattner2b7a2712009-07-08 00:31:33 +00003834 }
Dan Gohman3ce89f42010-04-30 17:19:19 +00003835
Chris Lattner2b7a2712009-07-08 00:31:33 +00003836 // sext(setcc x, y, cc) -> (select_cc x, y, -1, 0, cc)
Dan Gohmana7bcef12010-04-24 01:17:30 +00003837 unsigned ElementWidth = VT.getScalarType().getSizeInBits();
Dan Gohman5cbd37e2009-08-06 09:18:59 +00003838 SDValue NegOne =
Dan Gohmana7bcef12010-04-24 01:17:30 +00003839 DAG.getConstant(APInt::getAllOnesValue(ElementWidth), VT);
Scott Michelfdc40a02009-02-17 22:15:04 +00003840 SDValue SCC =
Bill Wendling836ca7d2009-01-30 23:59:18 +00003841 SimplifySelectCC(N->getDebugLoc(), N0.getOperand(0), N0.getOperand(1),
Dan Gohman5cbd37e2009-08-06 09:18:59 +00003842 NegOne, DAG.getConstant(0, VT),
Chris Lattner1eba01e2007-04-11 06:50:51 +00003843 cast<CondCodeSDNode>(N0.getOperand(2))->get(), true);
Gabor Greifba36cb52008-08-28 21:40:38 +00003844 if (SCC.getNode()) return SCC;
Evan Cheng8c7ecaf2010-01-26 02:00:44 +00003845 if (!LegalOperations ||
3846 TLI.isOperationLegal(ISD::SETCC, TLI.getSetCCResultType(VT)))
3847 return DAG.getNode(ISD::SELECT, N->getDebugLoc(), VT,
3848 DAG.getSetCC(N->getDebugLoc(),
3849 TLI.getSetCCResultType(VT),
3850 N0.getOperand(0), N0.getOperand(1),
3851 cast<CondCodeSDNode>(N0.getOperand(2))->get()),
3852 NegOne, DAG.getConstant(0, VT));
Wesley Peckbf17cfa2010-11-23 03:31:01 +00003853 }
Scott Michelfdc40a02009-02-17 22:15:04 +00003854
Dan Gohman8f0ad582008-04-28 16:58:24 +00003855 // fold (sext x) -> (zext x) if the sign bit is known zero.
Duncan Sands25cf2272008-11-24 14:53:14 +00003856 if ((!LegalOperations || TLI.isOperationLegal(ISD::ZERO_EXTEND, VT)) &&
Dan Gohman187db7b2008-04-28 18:47:17 +00003857 DAG.SignBitIsZero(N0))
Bill Wendling6ce610f2009-01-30 22:23:15 +00003858 return DAG.getNode(ISD::ZERO_EXTEND, N->getDebugLoc(), VT, N0);
Scott Michelfdc40a02009-02-17 22:15:04 +00003859
Evan Chengb3a3d5e2010-04-28 07:10:39 +00003860 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00003861}
3862
Dan Gohman475871a2008-07-27 21:46:04 +00003863SDValue DAGCombiner::visitZERO_EXTEND(SDNode *N) {
3864 SDValue N0 = N->getOperand(0);
Owen Andersone50ed302009-08-10 22:56:29 +00003865 EVT VT = N->getValueType(0);
Nate Begeman1d4d4142005-09-01 00:19:25 +00003866
Nate Begeman1d4d4142005-09-01 00:19:25 +00003867 // fold (zext c1) -> c1
Reid Spencer3ed469c2006-11-02 20:25:50 +00003868 if (isa<ConstantSDNode>(N0))
Bill Wendling6ce610f2009-01-30 22:23:15 +00003869 return DAG.getNode(ISD::ZERO_EXTEND, N->getDebugLoc(), VT, N0);
Nate Begeman1d4d4142005-09-01 00:19:25 +00003870 // fold (zext (zext x)) -> (zext x)
Chris Lattner310b5782006-05-06 23:06:26 +00003871 // fold (zext (aext x)) -> (zext x)
3872 if (N0.getOpcode() == ISD::ZERO_EXTEND || N0.getOpcode() == ISD::ANY_EXTEND)
Bill Wendling6ce610f2009-01-30 22:23:15 +00003873 return DAG.getNode(ISD::ZERO_EXTEND, N->getDebugLoc(), VT,
3874 N0.getOperand(0));
Chris Lattner6007b842006-09-21 06:00:20 +00003875
Evan Chengc88138f2007-03-22 01:54:19 +00003876 // fold (zext (truncate (load x))) -> (zext (smaller load x))
3877 // fold (zext (truncate (srl (load x), c))) -> (zext (small load (x+c/n)))
Dale Johannesen2041a0e2007-03-30 21:38:07 +00003878 if (N0.getOpcode() == ISD::TRUNCATE) {
Gabor Greifba36cb52008-08-28 21:40:38 +00003879 SDValue NarrowLoad = ReduceLoadWidth(N0.getNode());
3880 if (NarrowLoad.getNode()) {
Dale Johannesen61734eb2010-05-25 17:50:03 +00003881 SDNode* oye = N0.getNode()->getOperand(0).getNode();
3882 if (NarrowLoad.getNode() != N0.getNode()) {
Gabor Greifba36cb52008-08-28 21:40:38 +00003883 CombineTo(N0.getNode(), NarrowLoad);
Dale Johannesen61734eb2010-05-25 17:50:03 +00003884 // CombineTo deleted the truncate, if needed, but not what's under it.
3885 AddToWorkList(oye);
3886 }
Bill Wendling6ce610f2009-01-30 22:23:15 +00003887 return DAG.getNode(ISD::ZERO_EXTEND, N->getDebugLoc(), VT, NarrowLoad);
Evan Cheng0b063de2007-03-23 02:16:52 +00003888 }
Evan Chengc88138f2007-03-22 01:54:19 +00003889 }
3890
Chris Lattner6007b842006-09-21 06:00:20 +00003891 // fold (zext (truncate x)) -> (and x, mask)
3892 if (N0.getOpcode() == ISD::TRUNCATE &&
Dan Gohman4e39e9d2010-06-24 14:30:44 +00003893 (!LegalOperations || TLI.isOperationLegal(ISD::AND, VT))) {
Dan Gohman394d6292010-11-03 01:47:46 +00003894
3895 // fold (zext (truncate (load x))) -> (zext (smaller load x))
3896 // fold (zext (truncate (srl (load x), c))) -> (zext (smaller load (x+c/n)))
3897 SDValue NarrowLoad = ReduceLoadWidth(N0.getNode());
3898 if (NarrowLoad.getNode()) {
3899 SDNode* oye = N0.getNode()->getOperand(0).getNode();
3900 if (NarrowLoad.getNode() != N0.getNode()) {
3901 CombineTo(N0.getNode(), NarrowLoad);
3902 // CombineTo deleted the truncate, if needed, but not what's under it.
3903 AddToWorkList(oye);
3904 }
3905 return SDValue(N, 0); // Return N so it doesn't get rechecked!
3906 }
3907
Dan Gohman475871a2008-07-27 21:46:04 +00003908 SDValue Op = N0.getOperand(0);
Duncan Sands8e4eb092008-06-08 20:54:56 +00003909 if (Op.getValueType().bitsLT(VT)) {
Bill Wendling9729c5a2009-01-31 03:12:48 +00003910 Op = DAG.getNode(ISD::ANY_EXTEND, N->getDebugLoc(), VT, Op);
Duncan Sands8e4eb092008-06-08 20:54:56 +00003911 } else if (Op.getValueType().bitsGT(VT)) {
Bill Wendling9729c5a2009-01-31 03:12:48 +00003912 Op = DAG.getNode(ISD::TRUNCATE, N->getDebugLoc(), VT, Op);
Chris Lattner6007b842006-09-21 06:00:20 +00003913 }
Dan Gohman87862e72009-12-11 21:31:27 +00003914 return DAG.getZeroExtendInReg(Op, N->getDebugLoc(),
3915 N0.getValueType().getScalarType());
Chris Lattner6007b842006-09-21 06:00:20 +00003916 }
Scott Michelfdc40a02009-02-17 22:15:04 +00003917
Dan Gohman97121ba2009-04-08 00:15:30 +00003918 // Fold (zext (and (trunc x), cst)) -> (and x, cst),
3919 // if either of the casts is not free.
Chris Lattner111c2282006-09-21 06:14:31 +00003920 if (N0.getOpcode() == ISD::AND &&
3921 N0.getOperand(0).getOpcode() == ISD::TRUNCATE &&
Dan Gohman97121ba2009-04-08 00:15:30 +00003922 N0.getOperand(1).getOpcode() == ISD::Constant &&
3923 (!TLI.isTruncateFree(N0.getOperand(0).getOperand(0).getValueType(),
3924 N0.getValueType()) ||
3925 !TLI.isZExtFree(N0.getValueType(), VT))) {
Dan Gohman475871a2008-07-27 21:46:04 +00003926 SDValue X = N0.getOperand(0).getOperand(0);
Duncan Sands8e4eb092008-06-08 20:54:56 +00003927 if (X.getValueType().bitsLT(VT)) {
Bill Wendling9729c5a2009-01-31 03:12:48 +00003928 X = DAG.getNode(ISD::ANY_EXTEND, X.getDebugLoc(), VT, X);
Duncan Sands8e4eb092008-06-08 20:54:56 +00003929 } else if (X.getValueType().bitsGT(VT)) {
Bill Wendling9729c5a2009-01-31 03:12:48 +00003930 X = DAG.getNode(ISD::TRUNCATE, X.getDebugLoc(), VT, X);
Chris Lattner111c2282006-09-21 06:14:31 +00003931 }
Dan Gohman220a8232008-03-03 23:51:38 +00003932 APInt Mask = cast<ConstantSDNode>(N0.getOperand(1))->getAPIntValue();
Jay Foad40f8f622010-12-07 08:25:19 +00003933 Mask = Mask.zext(VT.getSizeInBits());
Bill Wendling6ce610f2009-01-30 22:23:15 +00003934 return DAG.getNode(ISD::AND, N->getDebugLoc(), VT,
3935 X, DAG.getConstant(Mask, VT));
Chris Lattner111c2282006-09-21 06:14:31 +00003936 }
Scott Michelfdc40a02009-02-17 22:15:04 +00003937
Evan Cheng110dec22005-12-14 02:19:23 +00003938 // fold (zext (load x)) -> (zext (truncate (zextload x)))
Nadav Rotemed9b9342011-02-20 12:37:50 +00003939 // None of the supported targets knows how to perform load and vector_zext
Nadav Rotemfcd96192011-02-27 07:40:43 +00003940 // on vectors in one instruction. We only perform this transformation on
3941 // scalars.
Nadav Rotemed9b9342011-02-20 12:37:50 +00003942 if (ISD::isNON_EXTLoad(N0.getNode()) && !VT.isVector() &&
Duncan Sands25cf2272008-11-24 14:53:14 +00003943 ((!LegalOperations && !cast<LoadSDNode>(N0)->isVolatile()) ||
Evan Cheng03294662008-10-14 21:26:46 +00003944 TLI.isLoadExtLegal(ISD::ZEXTLOAD, N0.getValueType()))) {
Evan Cheng3c3ddb32007-10-29 19:58:20 +00003945 bool DoXform = true;
3946 SmallVector<SDNode*, 4> SetCCs;
3947 if (!N0.hasOneUse())
3948 DoXform = ExtendUsesToFormExtLoad(N, N0, ISD::ZERO_EXTEND, SetCCs, TLI);
3949 if (DoXform) {
3950 LoadSDNode *LN0 = cast<LoadSDNode>(N0);
Stuart Hastingsa9011292011-02-16 16:23:55 +00003951 SDValue ExtLoad = DAG.getExtLoad(ISD::ZEXTLOAD, N->getDebugLoc(), VT,
Bill Wendling6ce610f2009-01-30 22:23:15 +00003952 LN0->getChain(),
Chris Lattner3d6ccfb2010-09-21 17:04:51 +00003953 LN0->getBasePtr(), LN0->getPointerInfo(),
Duncan Sands25cf2272008-11-24 14:53:14 +00003954 N0.getValueType(),
David Greene1e559442010-02-15 17:00:31 +00003955 LN0->isVolatile(), LN0->isNonTemporal(),
3956 LN0->getAlignment());
Evan Cheng3c3ddb32007-10-29 19:58:20 +00003957 CombineTo(N, ExtLoad);
Bill Wendling6ce610f2009-01-30 22:23:15 +00003958 SDValue Trunc = DAG.getNode(ISD::TRUNCATE, N0.getDebugLoc(),
3959 N0.getValueType(), ExtLoad);
Gabor Greifba36cb52008-08-28 21:40:38 +00003960 CombineTo(N0.getNode(), Trunc, ExtLoad.getValue(1));
Bill Wendling6ce610f2009-01-30 22:23:15 +00003961
Evan Cheng3c3ddb32007-10-29 19:58:20 +00003962 // Extend SetCC uses if necessary.
3963 for (unsigned i = 0, e = SetCCs.size(); i != e; ++i) {
3964 SDNode *SetCC = SetCCs[i];
Dan Gohman475871a2008-07-27 21:46:04 +00003965 SmallVector<SDValue, 4> Ops;
Bill Wendling6ce610f2009-01-30 22:23:15 +00003966
Evan Cheng3c3ddb32007-10-29 19:58:20 +00003967 for (unsigned j = 0; j != 2; ++j) {
Dan Gohman475871a2008-07-27 21:46:04 +00003968 SDValue SOp = SetCC->getOperand(j);
Evan Cheng3c3ddb32007-10-29 19:58:20 +00003969 if (SOp == Trunc)
3970 Ops.push_back(ExtLoad);
3971 else
Bill Wendling9729c5a2009-01-31 03:12:48 +00003972 Ops.push_back(DAG.getNode(ISD::ZERO_EXTEND,
3973 N->getDebugLoc(), VT, SOp));
Bill Wendling6ce610f2009-01-30 22:23:15 +00003974 }
3975
Evan Cheng3c3ddb32007-10-29 19:58:20 +00003976 Ops.push_back(SetCC->getOperand(2));
Bill Wendling9729c5a2009-01-31 03:12:48 +00003977 CombineTo(SetCC, DAG.getNode(ISD::SETCC, N->getDebugLoc(),
Bill Wendling6ce610f2009-01-30 22:23:15 +00003978 SetCC->getValueType(0),
Evan Cheng3c3ddb32007-10-29 19:58:20 +00003979 &Ops[0], Ops.size()));
3980 }
Bill Wendling6ce610f2009-01-30 22:23:15 +00003981
Dan Gohman475871a2008-07-27 21:46:04 +00003982 return SDValue(N, 0); // Return N so it doesn't get rechecked!
Evan Cheng3c3ddb32007-10-29 19:58:20 +00003983 }
Evan Cheng110dec22005-12-14 02:19:23 +00003984 }
Chris Lattnerad25d4e2005-12-14 19:05:06 +00003985
3986 // fold (zext (zextload x)) -> (zext (truncate (zextload x)))
3987 // fold (zext ( extload x)) -> (zext (truncate (zextload x)))
Gabor Greifba36cb52008-08-28 21:40:38 +00003988 if ((ISD::isZEXTLoad(N0.getNode()) || ISD::isEXTLoad(N0.getNode())) &&
3989 ISD::isUNINDEXEDLoad(N0.getNode()) && N0.hasOneUse()) {
Evan Cheng466685d2006-10-09 20:57:25 +00003990 LoadSDNode *LN0 = cast<LoadSDNode>(N0);
Dan Gohman8a55ce42009-09-23 21:02:20 +00003991 EVT MemVT = LN0->getMemoryVT();
Duncan Sands25cf2272008-11-24 14:53:14 +00003992 if ((!LegalOperations && !LN0->isVolatile()) ||
Dan Gohman8a55ce42009-09-23 21:02:20 +00003993 TLI.isLoadExtLegal(ISD::ZEXTLOAD, MemVT)) {
Stuart Hastingsa9011292011-02-16 16:23:55 +00003994 SDValue ExtLoad = DAG.getExtLoad(ISD::ZEXTLOAD, N->getDebugLoc(), VT,
Bill Wendling6ce610f2009-01-30 22:23:15 +00003995 LN0->getChain(),
Chris Lattner3d6ccfb2010-09-21 17:04:51 +00003996 LN0->getBasePtr(), LN0->getPointerInfo(),
3997 MemVT,
David Greene1e559442010-02-15 17:00:31 +00003998 LN0->isVolatile(), LN0->isNonTemporal(),
3999 LN0->getAlignment());
Duncan Sandsd4b9c172008-06-13 19:07:40 +00004000 CombineTo(N, ExtLoad);
Gabor Greif12632d22008-08-30 19:29:20 +00004001 CombineTo(N0.getNode(),
Bill Wendling6ce610f2009-01-30 22:23:15 +00004002 DAG.getNode(ISD::TRUNCATE, N0.getDebugLoc(), N0.getValueType(),
4003 ExtLoad),
Duncan Sandsd4b9c172008-06-13 19:07:40 +00004004 ExtLoad.getValue(1));
Dan Gohman475871a2008-07-27 21:46:04 +00004005 return SDValue(N, 0); // Return N so it doesn't get rechecked!
Duncan Sandsd4b9c172008-06-13 19:07:40 +00004006 }
Chris Lattnerad25d4e2005-12-14 19:05:06 +00004007 }
Scott Michelfdc40a02009-02-17 22:15:04 +00004008
Chris Lattner20a35c32007-04-11 05:32:27 +00004009 if (N0.getOpcode() == ISD::SETCC) {
Evan Cheng0a942db2010-05-19 01:08:17 +00004010 if (!LegalOperations && VT.isVector()) {
4011 // zext(setcc) -> (and (vsetcc), (1, 1, ...) for vectors.
4012 // Only do this before legalize for now.
4013 EVT N0VT = N0.getOperand(0).getValueType();
4014 EVT EltVT = VT.getVectorElementType();
4015 SmallVector<SDValue,8> OneOps(VT.getVectorNumElements(),
4016 DAG.getConstant(1, EltVT));
4017 if (VT.getSizeInBits() == N0VT.getSizeInBits()) {
4018 // We know that the # elements of the results is the same as the
4019 // # elements of the compare (and the # elements of the compare result
4020 // for that matter). Check to see that they are the same size. If so,
4021 // we know that the element size of the sext'd result matches the
4022 // element size of the compare operands.
4023 return DAG.getNode(ISD::AND, N->getDebugLoc(), VT,
4024 DAG.getVSetCC(N->getDebugLoc(), VT, N0.getOperand(0),
4025 N0.getOperand(1),
4026 cast<CondCodeSDNode>(N0.getOperand(2))->get()),
4027 DAG.getNode(ISD::BUILD_VECTOR, N->getDebugLoc(), VT,
4028 &OneOps[0], OneOps.size()));
4029 } else {
4030 // If the desired elements are smaller or larger than the source
4031 // elements we can use a matching integer vector type and then
4032 // truncate/sign extend
4033 EVT MatchingElementType =
4034 EVT::getIntegerVT(*DAG.getContext(),
4035 N0VT.getScalarType().getSizeInBits());
4036 EVT MatchingVectorType =
4037 EVT::getVectorVT(*DAG.getContext(), MatchingElementType,
4038 N0VT.getVectorNumElements());
4039 SDValue VsetCC =
4040 DAG.getVSetCC(N->getDebugLoc(), MatchingVectorType, N0.getOperand(0),
4041 N0.getOperand(1),
4042 cast<CondCodeSDNode>(N0.getOperand(2))->get());
4043 return DAG.getNode(ISD::AND, N->getDebugLoc(), VT,
4044 DAG.getSExtOrTrunc(VsetCC, N->getDebugLoc(), VT),
4045 DAG.getNode(ISD::BUILD_VECTOR, N->getDebugLoc(), VT,
4046 &OneOps[0], OneOps.size()));
4047 }
4048 }
4049
4050 // zext(setcc x,y,cc) -> select_cc x, y, 1, 0, cc
Scott Michelfdc40a02009-02-17 22:15:04 +00004051 SDValue SCC =
Bill Wendling836ca7d2009-01-30 23:59:18 +00004052 SimplifySelectCC(N->getDebugLoc(), N0.getOperand(0), N0.getOperand(1),
Chris Lattner20a35c32007-04-11 05:32:27 +00004053 DAG.getConstant(1, VT), DAG.getConstant(0, VT),
Chris Lattner1eba01e2007-04-11 06:50:51 +00004054 cast<CondCodeSDNode>(N0.getOperand(2))->get(), true);
Gabor Greifba36cb52008-08-28 21:40:38 +00004055 if (SCC.getNode()) return SCC;
Chris Lattner20a35c32007-04-11 05:32:27 +00004056 }
Scott Michelfdc40a02009-02-17 22:15:04 +00004057
Evan Cheng9818c042009-12-15 03:00:32 +00004058 // (zext (shl (zext x), cst)) -> (shl (zext x), cst)
Evan Cheng99b653c2009-12-15 00:41:36 +00004059 if ((N0.getOpcode() == ISD::SHL || N0.getOpcode() == ISD::SRL) &&
Evan Cheng9818c042009-12-15 03:00:32 +00004060 isa<ConstantSDNode>(N0.getOperand(1)) &&
Evan Cheng99b653c2009-12-15 00:41:36 +00004061 N0.getOperand(0).getOpcode() == ISD::ZERO_EXTEND &&
4062 N0.hasOneUse()) {
Chris Lattnere0751182011-02-13 19:09:16 +00004063 SDValue ShAmt = N0.getOperand(1);
4064 unsigned ShAmtVal = cast<ConstantSDNode>(ShAmt)->getZExtValue();
Evan Cheng9818c042009-12-15 03:00:32 +00004065 if (N0.getOpcode() == ISD::SHL) {
Chris Lattnere0751182011-02-13 19:09:16 +00004066 SDValue InnerZExt = N0.getOperand(0);
Evan Cheng9818c042009-12-15 03:00:32 +00004067 // If the original shl may be shifting out bits, do not perform this
4068 // transformation.
Chris Lattnere0751182011-02-13 19:09:16 +00004069 unsigned KnownZeroBits = InnerZExt.getValueType().getSizeInBits() -
4070 InnerZExt.getOperand(0).getValueType().getSizeInBits();
4071 if (ShAmtVal > KnownZeroBits)
Evan Cheng9818c042009-12-15 03:00:32 +00004072 return SDValue();
4073 }
Chris Lattnere0751182011-02-13 19:09:16 +00004074
4075 DebugLoc DL = N->getDebugLoc();
Owen Anderson95771af2011-02-25 21:41:48 +00004076
4077 // Ensure that the shift amount is wide enough for the shifted value.
Chris Lattnere0751182011-02-13 19:09:16 +00004078 if (VT.getSizeInBits() >= 256)
4079 ShAmt = DAG.getNode(ISD::ZERO_EXTEND, DL, MVT::i32, ShAmt);
Owen Anderson95771af2011-02-25 21:41:48 +00004080
Chris Lattnere0751182011-02-13 19:09:16 +00004081 return DAG.getNode(N0.getOpcode(), DL, VT,
4082 DAG.getNode(ISD::ZERO_EXTEND, DL, VT, N0.getOperand(0)),
4083 ShAmt);
Evan Cheng99b653c2009-12-15 00:41:36 +00004084 }
4085
Evan Chengb3a3d5e2010-04-28 07:10:39 +00004086 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00004087}
4088
Dan Gohman475871a2008-07-27 21:46:04 +00004089SDValue DAGCombiner::visitANY_EXTEND(SDNode *N) {
4090 SDValue N0 = N->getOperand(0);
Owen Andersone50ed302009-08-10 22:56:29 +00004091 EVT VT = N->getValueType(0);
Scott Michelfdc40a02009-02-17 22:15:04 +00004092
Chris Lattner5ffc0662006-05-05 05:58:59 +00004093 // fold (aext c1) -> c1
Chris Lattner310b5782006-05-06 23:06:26 +00004094 if (isa<ConstantSDNode>(N0))
Bill Wendlingfc4b6772009-02-01 11:19:36 +00004095 return DAG.getNode(ISD::ANY_EXTEND, N->getDebugLoc(), VT, N0);
Chris Lattner5ffc0662006-05-05 05:58:59 +00004096 // fold (aext (aext x)) -> (aext x)
4097 // fold (aext (zext x)) -> (zext x)
4098 // fold (aext (sext x)) -> (sext x)
4099 if (N0.getOpcode() == ISD::ANY_EXTEND ||
4100 N0.getOpcode() == ISD::ZERO_EXTEND ||
4101 N0.getOpcode() == ISD::SIGN_EXTEND)
Bill Wendling683c9572009-01-30 22:27:33 +00004102 return DAG.getNode(N0.getOpcode(), N->getDebugLoc(), VT, N0.getOperand(0));
Scott Michelfdc40a02009-02-17 22:15:04 +00004103
Evan Chengc88138f2007-03-22 01:54:19 +00004104 // fold (aext (truncate (load x))) -> (aext (smaller load x))
4105 // fold (aext (truncate (srl (load x), c))) -> (aext (small load (x+c/n)))
4106 if (N0.getOpcode() == ISD::TRUNCATE) {
Gabor Greifba36cb52008-08-28 21:40:38 +00004107 SDValue NarrowLoad = ReduceLoadWidth(N0.getNode());
4108 if (NarrowLoad.getNode()) {
Dale Johannesen86234c32010-05-25 18:47:23 +00004109 SDNode* oye = N0.getNode()->getOperand(0).getNode();
4110 if (NarrowLoad.getNode() != N0.getNode()) {
Gabor Greifba36cb52008-08-28 21:40:38 +00004111 CombineTo(N0.getNode(), NarrowLoad);
Dale Johannesen86234c32010-05-25 18:47:23 +00004112 // CombineTo deleted the truncate, if needed, but not what's under it.
4113 AddToWorkList(oye);
4114 }
Bill Wendling683c9572009-01-30 22:27:33 +00004115 return DAG.getNode(ISD::ANY_EXTEND, N->getDebugLoc(), VT, NarrowLoad);
Evan Cheng0b063de2007-03-23 02:16:52 +00004116 }
Evan Chengc88138f2007-03-22 01:54:19 +00004117 }
4118
Chris Lattner84750582006-09-20 06:29:17 +00004119 // fold (aext (truncate x))
4120 if (N0.getOpcode() == ISD::TRUNCATE) {
Dan Gohman475871a2008-07-27 21:46:04 +00004121 SDValue TruncOp = N0.getOperand(0);
Chris Lattner84750582006-09-20 06:29:17 +00004122 if (TruncOp.getValueType() == VT)
4123 return TruncOp; // x iff x size == zext size.
Duncan Sands8e4eb092008-06-08 20:54:56 +00004124 if (TruncOp.getValueType().bitsGT(VT))
Bill Wendling683c9572009-01-30 22:27:33 +00004125 return DAG.getNode(ISD::TRUNCATE, N->getDebugLoc(), VT, TruncOp);
4126 return DAG.getNode(ISD::ANY_EXTEND, N->getDebugLoc(), VT, TruncOp);
Chris Lattner84750582006-09-20 06:29:17 +00004127 }
Scott Michelfdc40a02009-02-17 22:15:04 +00004128
Dan Gohman97121ba2009-04-08 00:15:30 +00004129 // Fold (aext (and (trunc x), cst)) -> (and x, cst)
4130 // if the trunc is not free.
Chris Lattner0e4b9222006-09-21 06:40:43 +00004131 if (N0.getOpcode() == ISD::AND &&
4132 N0.getOperand(0).getOpcode() == ISD::TRUNCATE &&
Dan Gohman97121ba2009-04-08 00:15:30 +00004133 N0.getOperand(1).getOpcode() == ISD::Constant &&
4134 !TLI.isTruncateFree(N0.getOperand(0).getOperand(0).getValueType(),
4135 N0.getValueType())) {
Dan Gohman475871a2008-07-27 21:46:04 +00004136 SDValue X = N0.getOperand(0).getOperand(0);
Duncan Sands8e4eb092008-06-08 20:54:56 +00004137 if (X.getValueType().bitsLT(VT)) {
Bill Wendling9729c5a2009-01-31 03:12:48 +00004138 X = DAG.getNode(ISD::ANY_EXTEND, N->getDebugLoc(), VT, X);
Duncan Sands8e4eb092008-06-08 20:54:56 +00004139 } else if (X.getValueType().bitsGT(VT)) {
Bill Wendling9729c5a2009-01-31 03:12:48 +00004140 X = DAG.getNode(ISD::TRUNCATE, N->getDebugLoc(), VT, X);
Chris Lattner0e4b9222006-09-21 06:40:43 +00004141 }
Dan Gohman220a8232008-03-03 23:51:38 +00004142 APInt Mask = cast<ConstantSDNode>(N0.getOperand(1))->getAPIntValue();
Jay Foad40f8f622010-12-07 08:25:19 +00004143 Mask = Mask.zext(VT.getSizeInBits());
Bill Wendling683c9572009-01-30 22:27:33 +00004144 return DAG.getNode(ISD::AND, N->getDebugLoc(), VT,
4145 X, DAG.getConstant(Mask, VT));
Chris Lattner0e4b9222006-09-21 06:40:43 +00004146 }
Scott Michelfdc40a02009-02-17 22:15:04 +00004147
Chris Lattner5ffc0662006-05-05 05:58:59 +00004148 // fold (aext (load x)) -> (aext (truncate (extload x)))
Nadav Rotem8c20ec52011-02-24 21:01:34 +00004149 // None of the supported targets knows how to perform load and any_ext
Nadav Rotemfcd96192011-02-27 07:40:43 +00004150 // on vectors in one instruction. We only perform this transformation on
4151 // scalars.
Nadav Rotem8c20ec52011-02-24 21:01:34 +00004152 if (ISD::isNON_EXTLoad(N0.getNode()) && !VT.isVector() &&
Duncan Sands25cf2272008-11-24 14:53:14 +00004153 ((!LegalOperations && !cast<LoadSDNode>(N0)->isVolatile()) ||
Evan Cheng03294662008-10-14 21:26:46 +00004154 TLI.isLoadExtLegal(ISD::EXTLOAD, N0.getValueType()))) {
Dan Gohman57fc82d2009-04-09 03:51:29 +00004155 bool DoXform = true;
4156 SmallVector<SDNode*, 4> SetCCs;
4157 if (!N0.hasOneUse())
4158 DoXform = ExtendUsesToFormExtLoad(N, N0, ISD::ANY_EXTEND, SetCCs, TLI);
4159 if (DoXform) {
4160 LoadSDNode *LN0 = cast<LoadSDNode>(N0);
Stuart Hastingsa9011292011-02-16 16:23:55 +00004161 SDValue ExtLoad = DAG.getExtLoad(ISD::EXTLOAD, N->getDebugLoc(), VT,
Dan Gohman57fc82d2009-04-09 03:51:29 +00004162 LN0->getChain(),
Chris Lattner3d6ccfb2010-09-21 17:04:51 +00004163 LN0->getBasePtr(), LN0->getPointerInfo(),
Dan Gohman57fc82d2009-04-09 03:51:29 +00004164 N0.getValueType(),
David Greene1e559442010-02-15 17:00:31 +00004165 LN0->isVolatile(), LN0->isNonTemporal(),
4166 LN0->getAlignment());
Dan Gohman57fc82d2009-04-09 03:51:29 +00004167 CombineTo(N, ExtLoad);
4168 SDValue Trunc = DAG.getNode(ISD::TRUNCATE, N0.getDebugLoc(),
4169 N0.getValueType(), ExtLoad);
4170 CombineTo(N0.getNode(), Trunc, ExtLoad.getValue(1));
4171
4172 // Extend SetCC uses if necessary.
4173 for (unsigned i = 0, e = SetCCs.size(); i != e; ++i) {
4174 SDNode *SetCC = SetCCs[i];
4175 SmallVector<SDValue, 4> Ops;
4176
4177 for (unsigned j = 0; j != 2; ++j) {
4178 SDValue SOp = SetCC->getOperand(j);
4179 if (SOp == Trunc)
4180 Ops.push_back(ExtLoad);
4181 else
4182 Ops.push_back(DAG.getNode(ISD::ANY_EXTEND,
4183 N->getDebugLoc(), VT, SOp));
4184 }
4185
4186 Ops.push_back(SetCC->getOperand(2));
4187 CombineTo(SetCC, DAG.getNode(ISD::SETCC, N->getDebugLoc(),
4188 SetCC->getValueType(0),
4189 &Ops[0], Ops.size()));
4190 }
4191
4192 return SDValue(N, 0); // Return N so it doesn't get rechecked!
4193 }
Chris Lattner5ffc0662006-05-05 05:58:59 +00004194 }
Scott Michelfdc40a02009-02-17 22:15:04 +00004195
Chris Lattner5ffc0662006-05-05 05:58:59 +00004196 // fold (aext (zextload x)) -> (aext (truncate (zextload x)))
4197 // fold (aext (sextload x)) -> (aext (truncate (sextload x)))
4198 // fold (aext ( extload x)) -> (aext (truncate (extload x)))
Evan Cheng83060c52007-03-07 08:07:03 +00004199 if (N0.getOpcode() == ISD::LOAD &&
Gabor Greifba36cb52008-08-28 21:40:38 +00004200 !ISD::isNON_EXTLoad(N0.getNode()) && ISD::isUNINDEXEDLoad(N0.getNode()) &&
Evan Cheng466685d2006-10-09 20:57:25 +00004201 N0.hasOneUse()) {
4202 LoadSDNode *LN0 = cast<LoadSDNode>(N0);
Dan Gohman8a55ce42009-09-23 21:02:20 +00004203 EVT MemVT = LN0->getMemoryVT();
Stuart Hastingsa9011292011-02-16 16:23:55 +00004204 SDValue ExtLoad = DAG.getExtLoad(LN0->getExtensionType(), N->getDebugLoc(),
4205 VT, LN0->getChain(), LN0->getBasePtr(),
Chris Lattner3d6ccfb2010-09-21 17:04:51 +00004206 LN0->getPointerInfo(), MemVT,
David Greene1e559442010-02-15 17:00:31 +00004207 LN0->isVolatile(), LN0->isNonTemporal(),
4208 LN0->getAlignment());
Chris Lattner5ffc0662006-05-05 05:58:59 +00004209 CombineTo(N, ExtLoad);
Evan Cheng45299662008-08-29 23:20:46 +00004210 CombineTo(N0.getNode(),
Bill Wendling683c9572009-01-30 22:27:33 +00004211 DAG.getNode(ISD::TRUNCATE, N0.getDebugLoc(),
4212 N0.getValueType(), ExtLoad),
Chris Lattner5ffc0662006-05-05 05:58:59 +00004213 ExtLoad.getValue(1));
Dan Gohman475871a2008-07-27 21:46:04 +00004214 return SDValue(N, 0); // Return N so it doesn't get rechecked!
Chris Lattner5ffc0662006-05-05 05:58:59 +00004215 }
Scott Michelfdc40a02009-02-17 22:15:04 +00004216
Chris Lattner20a35c32007-04-11 05:32:27 +00004217 if (N0.getOpcode() == ISD::SETCC) {
Evan Cheng0a942db2010-05-19 01:08:17 +00004218 // aext(setcc) -> sext_in_reg(vsetcc) for vectors.
4219 // Only do this before legalize for now.
4220 if (VT.isVector() && !LegalOperations) {
4221 EVT N0VT = N0.getOperand(0).getValueType();
4222 // We know that the # elements of the results is the same as the
4223 // # elements of the compare (and the # elements of the compare result
4224 // for that matter). Check to see that they are the same size. If so,
4225 // we know that the element size of the sext'd result matches the
4226 // element size of the compare operands.
4227 if (VT.getSizeInBits() == N0VT.getSizeInBits())
Duncan Sands34727662010-07-12 08:16:59 +00004228 return DAG.getVSetCC(N->getDebugLoc(), VT, N0.getOperand(0),
4229 N0.getOperand(1),
4230 cast<CondCodeSDNode>(N0.getOperand(2))->get());
Evan Cheng0a942db2010-05-19 01:08:17 +00004231 // If the desired elements are smaller or larger than the source
4232 // elements we can use a matching integer vector type and then
4233 // truncate/sign extend
4234 else {
Duncan Sands34727662010-07-12 08:16:59 +00004235 EVT MatchingElementType =
4236 EVT::getIntegerVT(*DAG.getContext(),
4237 N0VT.getScalarType().getSizeInBits());
4238 EVT MatchingVectorType =
4239 EVT::getVectorVT(*DAG.getContext(), MatchingElementType,
4240 N0VT.getVectorNumElements());
4241 SDValue VsetCC =
4242 DAG.getVSetCC(N->getDebugLoc(), MatchingVectorType, N0.getOperand(0),
4243 N0.getOperand(1),
4244 cast<CondCodeSDNode>(N0.getOperand(2))->get());
4245 return DAG.getSExtOrTrunc(VsetCC, N->getDebugLoc(), VT);
Evan Cheng0a942db2010-05-19 01:08:17 +00004246 }
4247 }
4248
4249 // aext(setcc x,y,cc) -> select_cc x, y, 1, 0, cc
Scott Michelfdc40a02009-02-17 22:15:04 +00004250 SDValue SCC =
Bill Wendling836ca7d2009-01-30 23:59:18 +00004251 SimplifySelectCC(N->getDebugLoc(), N0.getOperand(0), N0.getOperand(1),
Chris Lattner1eba01e2007-04-11 06:50:51 +00004252 DAG.getConstant(1, VT), DAG.getConstant(0, VT),
Chris Lattnerc24bbad2007-04-11 16:51:53 +00004253 cast<CondCodeSDNode>(N0.getOperand(2))->get(), true);
Gabor Greifba36cb52008-08-28 21:40:38 +00004254 if (SCC.getNode())
Chris Lattnerc56a81d2007-04-11 06:43:25 +00004255 return SCC;
Chris Lattner20a35c32007-04-11 05:32:27 +00004256 }
Scott Michelfdc40a02009-02-17 22:15:04 +00004257
Evan Chengb3a3d5e2010-04-28 07:10:39 +00004258 return SDValue();
Chris Lattner5ffc0662006-05-05 05:58:59 +00004259}
4260
Chris Lattner2b4c2792007-10-13 06:35:54 +00004261/// GetDemandedBits - See if the specified operand can be simplified with the
4262/// knowledge that only the bits specified by Mask are used. If so, return the
Dan Gohman475871a2008-07-27 21:46:04 +00004263/// simpler operand, otherwise return a null SDValue.
4264SDValue DAGCombiner::GetDemandedBits(SDValue V, const APInt &Mask) {
Chris Lattner2b4c2792007-10-13 06:35:54 +00004265 switch (V.getOpcode()) {
4266 default: break;
4267 case ISD::OR:
4268 case ISD::XOR:
4269 // If the LHS or RHS don't contribute bits to the or, drop them.
4270 if (DAG.MaskedValueIsZero(V.getOperand(0), Mask))
4271 return V.getOperand(1);
4272 if (DAG.MaskedValueIsZero(V.getOperand(1), Mask))
4273 return V.getOperand(0);
4274 break;
Chris Lattnere33544c2007-10-13 06:58:48 +00004275 case ISD::SRL:
4276 // Only look at single-use SRLs.
Gabor Greifba36cb52008-08-28 21:40:38 +00004277 if (!V.getNode()->hasOneUse())
Chris Lattnere33544c2007-10-13 06:58:48 +00004278 break;
4279 if (ConstantSDNode *RHSC = dyn_cast<ConstantSDNode>(V.getOperand(1))) {
4280 // See if we can recursively simplify the LHS.
Dan Gohmanf5aeb1a2008-09-12 16:56:44 +00004281 unsigned Amt = RHSC->getZExtValue();
Bill Wendling8509c902009-01-30 22:33:24 +00004282
Dan Gohmancc91d632009-01-03 19:22:06 +00004283 // Watch out for shift count overflow though.
4284 if (Amt >= Mask.getBitWidth()) break;
Dan Gohman2e68b6f2008-02-25 21:11:39 +00004285 APInt NewMask = Mask << Amt;
Dan Gohman475871a2008-07-27 21:46:04 +00004286 SDValue SimplifyLHS = GetDemandedBits(V.getOperand(0), NewMask);
Bill Wendling8509c902009-01-30 22:33:24 +00004287 if (SimplifyLHS.getNode())
Scott Michelfdc40a02009-02-17 22:15:04 +00004288 return DAG.getNode(ISD::SRL, V.getDebugLoc(), V.getValueType(),
Chris Lattnere33544c2007-10-13 06:58:48 +00004289 SimplifyLHS, V.getOperand(1));
Chris Lattnere33544c2007-10-13 06:58:48 +00004290 }
Chris Lattner2b4c2792007-10-13 06:35:54 +00004291 }
Dan Gohman475871a2008-07-27 21:46:04 +00004292 return SDValue();
Chris Lattner2b4c2792007-10-13 06:35:54 +00004293}
4294
Evan Chengc88138f2007-03-22 01:54:19 +00004295/// ReduceLoadWidth - If the result of a wider load is shifted to right of N
4296/// bits and then truncated to a narrower type and where N is a multiple
4297/// of number of bits of the narrower type, transform it to a narrower load
4298/// from address + N / num of bits of new type. If the result is to be
4299/// extended, also fold the extension to form a extending load.
Dan Gohman475871a2008-07-27 21:46:04 +00004300SDValue DAGCombiner::ReduceLoadWidth(SDNode *N) {
Evan Chengc88138f2007-03-22 01:54:19 +00004301 unsigned Opc = N->getOpcode();
Dan Gohman4e39e9d2010-06-24 14:30:44 +00004302
Evan Chengc88138f2007-03-22 01:54:19 +00004303 ISD::LoadExtType ExtType = ISD::NON_EXTLOAD;
Dan Gohman475871a2008-07-27 21:46:04 +00004304 SDValue N0 = N->getOperand(0);
Owen Andersone50ed302009-08-10 22:56:29 +00004305 EVT VT = N->getValueType(0);
4306 EVT ExtVT = VT;
Evan Chengc88138f2007-03-22 01:54:19 +00004307
Dan Gohman7f8613e2008-08-14 20:04:46 +00004308 // This transformation isn't valid for vector loads.
4309 if (VT.isVector())
4310 return SDValue();
4311
Dan Gohmand1996362010-01-09 02:13:55 +00004312 // Special case: SIGN_EXTEND_INREG is basically truncating to ExtVT then
Evan Chenge177e302007-03-23 22:13:36 +00004313 // extended to VT.
Evan Chengc88138f2007-03-22 01:54:19 +00004314 if (Opc == ISD::SIGN_EXTEND_INREG) {
4315 ExtType = ISD::SEXTLOAD;
Owen Andersone50ed302009-08-10 22:56:29 +00004316 ExtVT = cast<VTSDNode>(N->getOperand(1))->getVT();
Dan Gohman4e39e9d2010-06-24 14:30:44 +00004317 } else if (Opc == ISD::SRL) {
Chris Lattner90b03642010-12-21 18:05:22 +00004318 // Another special-case: SRL is basically zero-extending a narrower value.
Dan Gohman4e39e9d2010-06-24 14:30:44 +00004319 ExtType = ISD::ZEXTLOAD;
4320 N0 = SDValue(N, 0);
4321 ConstantSDNode *N01 = dyn_cast<ConstantSDNode>(N0.getOperand(1));
4322 if (!N01) return SDValue();
4323 ExtVT = EVT::getIntegerVT(*DAG.getContext(),
4324 VT.getSizeInBits() - N01->getZExtValue());
Evan Chengc88138f2007-03-22 01:54:19 +00004325 }
Richard Osborne4e3740e2011-01-31 17:41:44 +00004326 if (LegalOperations && !TLI.isLoadExtLegal(ExtType, ExtVT))
4327 return SDValue();
Evan Chengc88138f2007-03-22 01:54:19 +00004328
Owen Andersone50ed302009-08-10 22:56:29 +00004329 unsigned EVTBits = ExtVT.getSizeInBits();
Owen Anderson95771af2011-02-25 21:41:48 +00004330
Chris Lattner7a2a7fa2010-12-22 08:01:44 +00004331 // Do not generate loads of non-round integer types since these can
4332 // be expensive (and would be wrong if the type is not byte sized).
4333 if (!ExtVT.isRound())
4334 return SDValue();
Owen Anderson95771af2011-02-25 21:41:48 +00004335
Evan Chengc88138f2007-03-22 01:54:19 +00004336 unsigned ShAmt = 0;
Chris Lattner7a2a7fa2010-12-22 08:01:44 +00004337 if (N0.getOpcode() == ISD::SRL && N0.hasOneUse()) {
Evan Chengc88138f2007-03-22 01:54:19 +00004338 if (ConstantSDNode *N01 = dyn_cast<ConstantSDNode>(N0.getOperand(1))) {
Dan Gohmanf5aeb1a2008-09-12 16:56:44 +00004339 ShAmt = N01->getZExtValue();
Evan Chengc88138f2007-03-22 01:54:19 +00004340 // Is the shift amount a multiple of size of VT?
4341 if ((ShAmt & (EVTBits-1)) == 0) {
4342 N0 = N0.getOperand(0);
Eli Friedmand68eea22009-08-19 08:46:10 +00004343 // Is the load width a multiple of size of VT?
4344 if ((N0.getValueType().getSizeInBits() & (EVTBits-1)) != 0)
Dan Gohman475871a2008-07-27 21:46:04 +00004345 return SDValue();
Evan Chengc88138f2007-03-22 01:54:19 +00004346 }
Wesley Peckbf17cfa2010-11-23 03:31:01 +00004347
Chris Lattnercbf68df2010-12-22 08:02:57 +00004348 // At this point, we must have a load or else we can't do the transform.
4349 if (!isa<LoadSDNode>(N0)) return SDValue();
Owen Anderson95771af2011-02-25 21:41:48 +00004350
Chris Lattner2831a192010-10-01 05:36:09 +00004351 // If the shift amount is larger than the input type then we're not
4352 // accessing any of the loaded bytes. If the load was a zextload/extload
4353 // then the result of the shift+trunc is zero/undef (handled elsewhere).
4354 // If the load was a sextload then the result is a splat of the sign bit
4355 // of the extended byte. This is not worth optimizing for.
Chris Lattnercbf68df2010-12-22 08:02:57 +00004356 if (ShAmt >= cast<LoadSDNode>(N0)->getMemoryVT().getSizeInBits())
Chris Lattner2831a192010-10-01 05:36:09 +00004357 return SDValue();
Evan Chengc88138f2007-03-22 01:54:19 +00004358 }
4359 }
4360
Dan Gohman394d6292010-11-03 01:47:46 +00004361 // If the load is shifted left (and the result isn't shifted back right),
4362 // we can fold the truncate through the shift.
4363 unsigned ShLeftAmt = 0;
4364 if (ShAmt == 0 && N0.getOpcode() == ISD::SHL && N0.hasOneUse() &&
Chris Lattner4c32bc22010-12-22 07:36:50 +00004365 ExtVT == VT && TLI.isNarrowingProfitable(N0.getValueType(), VT)) {
Dan Gohman394d6292010-11-03 01:47:46 +00004366 if (ConstantSDNode *N01 = dyn_cast<ConstantSDNode>(N0.getOperand(1))) {
4367 ShLeftAmt = N01->getZExtValue();
4368 N0 = N0.getOperand(0);
4369 }
4370 }
Owen Anderson95771af2011-02-25 21:41:48 +00004371
Chris Lattner4c32bc22010-12-22 07:36:50 +00004372 // If we haven't found a load, we can't narrow it. Don't transform one with
4373 // multiple uses, this would require adding a new load.
4374 if (!isa<LoadSDNode>(N0) || !N0.hasOneUse() ||
4375 // Don't change the width of a volatile load.
4376 cast<LoadSDNode>(N0)->isVolatile())
4377 return SDValue();
Owen Anderson95771af2011-02-25 21:41:48 +00004378
Chris Lattner7a2a7fa2010-12-22 08:01:44 +00004379 // Verify that we are actually reducing a load width here.
4380 if (cast<LoadSDNode>(N0)->getMemoryVT().getSizeInBits() < EVTBits)
Chris Lattner4c32bc22010-12-22 07:36:50 +00004381 return SDValue();
Owen Anderson95771af2011-02-25 21:41:48 +00004382
Chris Lattner4c32bc22010-12-22 07:36:50 +00004383 LoadSDNode *LN0 = cast<LoadSDNode>(N0);
4384 EVT PtrType = N0.getOperand(1).getValueType();
Bill Wendling8509c902009-01-30 22:33:24 +00004385
Chris Lattner4c32bc22010-12-22 07:36:50 +00004386 // For big endian targets, we need to adjust the offset to the pointer to
4387 // load the correct bytes.
4388 if (TLI.isBigEndian()) {
4389 unsigned LVTStoreBits = LN0->getMemoryVT().getStoreSizeInBits();
4390 unsigned EVTStoreBits = ExtVT.getStoreSizeInBits();
4391 ShAmt = LVTStoreBits - EVTStoreBits - ShAmt;
Evan Chengc88138f2007-03-22 01:54:19 +00004392 }
4393
Chris Lattner4c32bc22010-12-22 07:36:50 +00004394 uint64_t PtrOff = ShAmt / 8;
4395 unsigned NewAlign = MinAlign(LN0->getAlignment(), PtrOff);
4396 SDValue NewPtr = DAG.getNode(ISD::ADD, LN0->getDebugLoc(),
4397 PtrType, LN0->getBasePtr(),
4398 DAG.getConstant(PtrOff, PtrType));
4399 AddToWorkList(NewPtr.getNode());
4400
Chris Lattner7a2a7fa2010-12-22 08:01:44 +00004401 SDValue Load;
4402 if (ExtType == ISD::NON_EXTLOAD)
4403 Load = DAG.getLoad(VT, N0.getDebugLoc(), LN0->getChain(), NewPtr,
4404 LN0->getPointerInfo().getWithOffset(PtrOff),
4405 LN0->isVolatile(), LN0->isNonTemporal(), NewAlign);
4406 else
Stuart Hastingsa9011292011-02-16 16:23:55 +00004407 Load = DAG.getExtLoad(ExtType, N0.getDebugLoc(), VT, LN0->getChain(),NewPtr,
Chris Lattner7a2a7fa2010-12-22 08:01:44 +00004408 LN0->getPointerInfo().getWithOffset(PtrOff),
4409 ExtVT, LN0->isVolatile(), LN0->isNonTemporal(),
4410 NewAlign);
Chris Lattner4c32bc22010-12-22 07:36:50 +00004411
4412 // Replace the old load's chain with the new load's chain.
4413 WorkListRemover DeadNodes(*this);
4414 DAG.ReplaceAllUsesOfValueWith(N0.getValue(1), Load.getValue(1),
4415 &DeadNodes);
4416
4417 // Shift the result left, if we've swallowed a left shift.
4418 SDValue Result = Load;
4419 if (ShLeftAmt != 0) {
Owen Anderson95771af2011-02-25 21:41:48 +00004420 EVT ShImmTy = getShiftAmountTy(Result.getValueType());
Chris Lattner4c32bc22010-12-22 07:36:50 +00004421 if (!isUIntN(ShImmTy.getSizeInBits(), ShLeftAmt))
4422 ShImmTy = VT;
4423 Result = DAG.getNode(ISD::SHL, N0.getDebugLoc(), VT,
4424 Result, DAG.getConstant(ShLeftAmt, ShImmTy));
4425 }
4426
4427 // Return the new loaded value.
4428 return Result;
Evan Chengc88138f2007-03-22 01:54:19 +00004429}
4430
Dan Gohman475871a2008-07-27 21:46:04 +00004431SDValue DAGCombiner::visitSIGN_EXTEND_INREG(SDNode *N) {
4432 SDValue N0 = N->getOperand(0);
4433 SDValue N1 = N->getOperand(1);
Owen Andersone50ed302009-08-10 22:56:29 +00004434 EVT VT = N->getValueType(0);
4435 EVT EVT = cast<VTSDNode>(N1)->getVT();
Dan Gohman87862e72009-12-11 21:31:27 +00004436 unsigned VTBits = VT.getScalarType().getSizeInBits();
Dan Gohmand1996362010-01-09 02:13:55 +00004437 unsigned EVTBits = EVT.getScalarType().getSizeInBits();
Scott Michelfdc40a02009-02-17 22:15:04 +00004438
Nate Begeman1d4d4142005-09-01 00:19:25 +00004439 // fold (sext_in_reg c1) -> c1
Chris Lattnereaeda562006-05-08 20:59:41 +00004440 if (isa<ConstantSDNode>(N0) || N0.getOpcode() == ISD::UNDEF)
Bill Wendling8509c902009-01-30 22:33:24 +00004441 return DAG.getNode(ISD::SIGN_EXTEND_INREG, N->getDebugLoc(), VT, N0, N1);
Scott Michelfdc40a02009-02-17 22:15:04 +00004442
Chris Lattner541a24f2006-05-06 22:43:44 +00004443 // If the input is already sign extended, just drop the extension.
Dan Gohman87862e72009-12-11 21:31:27 +00004444 if (DAG.ComputeNumSignBits(N0) >= VTBits-EVTBits+1)
Chris Lattneree4ea922006-05-06 09:30:03 +00004445 return N0;
Scott Michelfdc40a02009-02-17 22:15:04 +00004446
Nate Begeman646d7e22005-09-02 21:18:40 +00004447 // fold (sext_in_reg (sext_in_reg x, VT2), VT1) -> (sext_in_reg x, minVT) pt2
4448 if (N0.getOpcode() == ISD::SIGN_EXTEND_INREG &&
Duncan Sands8e4eb092008-06-08 20:54:56 +00004449 EVT.bitsLT(cast<VTSDNode>(N0.getOperand(1))->getVT())) {
Bill Wendling8509c902009-01-30 22:33:24 +00004450 return DAG.getNode(ISD::SIGN_EXTEND_INREG, N->getDebugLoc(), VT,
4451 N0.getOperand(0), N1);
Nate Begeman646d7e22005-09-02 21:18:40 +00004452 }
Chris Lattner4b37e872006-05-08 21:18:59 +00004453
Dan Gohman75dcf082008-07-31 00:50:31 +00004454 // fold (sext_in_reg (sext x)) -> (sext x)
4455 // fold (sext_in_reg (aext x)) -> (sext x)
4456 // if x is small enough.
4457 if (N0.getOpcode() == ISD::SIGN_EXTEND || N0.getOpcode() == ISD::ANY_EXTEND) {
4458 SDValue N00 = N0.getOperand(0);
Evan Cheng003d7c42010-04-16 22:26:19 +00004459 if (N00.getValueType().getScalarType().getSizeInBits() <= EVTBits &&
4460 (!LegalOperations || TLI.isOperationLegal(ISD::SIGN_EXTEND, VT)))
Bill Wendling8509c902009-01-30 22:33:24 +00004461 return DAG.getNode(ISD::SIGN_EXTEND, N->getDebugLoc(), VT, N00, N1);
Dan Gohman75dcf082008-07-31 00:50:31 +00004462 }
4463
Chris Lattner95a5e052007-04-17 19:03:21 +00004464 // fold (sext_in_reg x) -> (zext_in_reg x) if the sign bit is known zero.
Dan Gohman2e68b6f2008-02-25 21:11:39 +00004465 if (DAG.MaskedValueIsZero(N0, APInt::getBitsSet(VTBits, EVTBits-1, EVTBits)))
Bill Wendlingfc4b6772009-02-01 11:19:36 +00004466 return DAG.getZeroExtendInReg(N0, N->getDebugLoc(), EVT);
Scott Michelfdc40a02009-02-17 22:15:04 +00004467
Chris Lattner95a5e052007-04-17 19:03:21 +00004468 // fold operands of sext_in_reg based on knowledge that the top bits are not
4469 // demanded.
Dan Gohman475871a2008-07-27 21:46:04 +00004470 if (SimplifyDemandedBits(SDValue(N, 0)))
4471 return SDValue(N, 0);
Scott Michelfdc40a02009-02-17 22:15:04 +00004472
Evan Chengc88138f2007-03-22 01:54:19 +00004473 // fold (sext_in_reg (load x)) -> (smaller sextload x)
4474 // fold (sext_in_reg (srl (load x), c)) -> (smaller sextload (x+c/evtbits))
Dan Gohman475871a2008-07-27 21:46:04 +00004475 SDValue NarrowLoad = ReduceLoadWidth(N);
Gabor Greifba36cb52008-08-28 21:40:38 +00004476 if (NarrowLoad.getNode())
Evan Chengc88138f2007-03-22 01:54:19 +00004477 return NarrowLoad;
4478
Bill Wendling8509c902009-01-30 22:33:24 +00004479 // fold (sext_in_reg (srl X, 24), i8) -> (sra X, 24)
4480 // fold (sext_in_reg (srl X, 23), i8) -> (sra X, 23) iff possible.
Chris Lattner4b37e872006-05-08 21:18:59 +00004481 // We already fold "(sext_in_reg (srl X, 25), i8) -> srl X, 25" above.
4482 if (N0.getOpcode() == ISD::SRL) {
4483 if (ConstantSDNode *ShAmt = dyn_cast<ConstantSDNode>(N0.getOperand(1)))
Dan Gohman87862e72009-12-11 21:31:27 +00004484 if (ShAmt->getZExtValue()+EVTBits <= VTBits) {
Chris Lattner4b37e872006-05-08 21:18:59 +00004485 // We can turn this into an SRA iff the input to the SRL is already sign
4486 // extended enough.
Dan Gohmanea859be2007-06-22 14:59:07 +00004487 unsigned InSignBits = DAG.ComputeNumSignBits(N0.getOperand(0));
Dan Gohman87862e72009-12-11 21:31:27 +00004488 if (VTBits-(ShAmt->getZExtValue()+EVTBits) < InSignBits)
Bill Wendling8509c902009-01-30 22:33:24 +00004489 return DAG.getNode(ISD::SRA, N->getDebugLoc(), VT,
4490 N0.getOperand(0), N0.getOperand(1));
Chris Lattner4b37e872006-05-08 21:18:59 +00004491 }
4492 }
Evan Chengc88138f2007-03-22 01:54:19 +00004493
Nate Begemanded49632005-10-13 03:11:28 +00004494 // fold (sext_inreg (extload x)) -> (sextload x)
Scott Michelfdc40a02009-02-17 22:15:04 +00004495 if (ISD::isEXTLoad(N0.getNode()) &&
Gabor Greifba36cb52008-08-28 21:40:38 +00004496 ISD::isUNINDEXEDLoad(N0.getNode()) &&
Dan Gohmanb625f2f2008-01-30 00:15:11 +00004497 EVT == cast<LoadSDNode>(N0)->getMemoryVT() &&
Duncan Sands25cf2272008-11-24 14:53:14 +00004498 ((!LegalOperations && !cast<LoadSDNode>(N0)->isVolatile()) ||
Evan Cheng03294662008-10-14 21:26:46 +00004499 TLI.isLoadExtLegal(ISD::SEXTLOAD, EVT))) {
Evan Cheng466685d2006-10-09 20:57:25 +00004500 LoadSDNode *LN0 = cast<LoadSDNode>(N0);
Stuart Hastingsa9011292011-02-16 16:23:55 +00004501 SDValue ExtLoad = DAG.getExtLoad(ISD::SEXTLOAD, N->getDebugLoc(), VT,
Bill Wendling8509c902009-01-30 22:33:24 +00004502 LN0->getChain(),
Chris Lattner3d6ccfb2010-09-21 17:04:51 +00004503 LN0->getBasePtr(), LN0->getPointerInfo(),
4504 EVT,
David Greene1e559442010-02-15 17:00:31 +00004505 LN0->isVolatile(), LN0->isNonTemporal(),
4506 LN0->getAlignment());
Chris Lattnerd4771842005-12-14 19:25:30 +00004507 CombineTo(N, ExtLoad);
Gabor Greifba36cb52008-08-28 21:40:38 +00004508 CombineTo(N0.getNode(), ExtLoad, ExtLoad.getValue(1));
Dan Gohman475871a2008-07-27 21:46:04 +00004509 return SDValue(N, 0); // Return N so it doesn't get rechecked!
Nate Begemanded49632005-10-13 03:11:28 +00004510 }
4511 // fold (sext_inreg (zextload x)) -> (sextload x) iff load has one use
Gabor Greifba36cb52008-08-28 21:40:38 +00004512 if (ISD::isZEXTLoad(N0.getNode()) && ISD::isUNINDEXEDLoad(N0.getNode()) &&
Evan Cheng83060c52007-03-07 08:07:03 +00004513 N0.hasOneUse() &&
Dan Gohmanb625f2f2008-01-30 00:15:11 +00004514 EVT == cast<LoadSDNode>(N0)->getMemoryVT() &&
Duncan Sands25cf2272008-11-24 14:53:14 +00004515 ((!LegalOperations && !cast<LoadSDNode>(N0)->isVolatile()) ||
Evan Cheng03294662008-10-14 21:26:46 +00004516 TLI.isLoadExtLegal(ISD::SEXTLOAD, EVT))) {
Evan Cheng466685d2006-10-09 20:57:25 +00004517 LoadSDNode *LN0 = cast<LoadSDNode>(N0);
Stuart Hastingsa9011292011-02-16 16:23:55 +00004518 SDValue ExtLoad = DAG.getExtLoad(ISD::SEXTLOAD, N->getDebugLoc(), VT,
Bill Wendling8509c902009-01-30 22:33:24 +00004519 LN0->getChain(),
Chris Lattner3d6ccfb2010-09-21 17:04:51 +00004520 LN0->getBasePtr(), LN0->getPointerInfo(),
4521 EVT,
David Greene1e559442010-02-15 17:00:31 +00004522 LN0->isVolatile(), LN0->isNonTemporal(),
4523 LN0->getAlignment());
Chris Lattnerd4771842005-12-14 19:25:30 +00004524 CombineTo(N, ExtLoad);
Gabor Greifba36cb52008-08-28 21:40:38 +00004525 CombineTo(N0.getNode(), ExtLoad, ExtLoad.getValue(1));
Dan Gohman475871a2008-07-27 21:46:04 +00004526 return SDValue(N, 0); // Return N so it doesn't get rechecked!
Nate Begemanded49632005-10-13 03:11:28 +00004527 }
Dan Gohman475871a2008-07-27 21:46:04 +00004528 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00004529}
4530
Dan Gohman475871a2008-07-27 21:46:04 +00004531SDValue DAGCombiner::visitTRUNCATE(SDNode *N) {
4532 SDValue N0 = N->getOperand(0);
Owen Andersone50ed302009-08-10 22:56:29 +00004533 EVT VT = N->getValueType(0);
Nate Begeman1d4d4142005-09-01 00:19:25 +00004534
4535 // noop truncate
4536 if (N0.getValueType() == N->getValueType(0))
Nate Begeman83e75ec2005-09-06 04:43:02 +00004537 return N0;
Nate Begeman1d4d4142005-09-01 00:19:25 +00004538 // fold (truncate c1) -> c1
Chris Lattner310b5782006-05-06 23:06:26 +00004539 if (isa<ConstantSDNode>(N0))
Bill Wendling67a67682009-01-30 22:44:24 +00004540 return DAG.getNode(ISD::TRUNCATE, N->getDebugLoc(), VT, N0);
Nate Begeman1d4d4142005-09-01 00:19:25 +00004541 // fold (truncate (truncate x)) -> (truncate x)
4542 if (N0.getOpcode() == ISD::TRUNCATE)
Bill Wendling67a67682009-01-30 22:44:24 +00004543 return DAG.getNode(ISD::TRUNCATE, N->getDebugLoc(), VT, N0.getOperand(0));
Nate Begeman1d4d4142005-09-01 00:19:25 +00004544 // fold (truncate (ext x)) -> (ext x) or (truncate x) or x
Chris Lattner7f893c02010-04-07 18:13:33 +00004545 if (N0.getOpcode() == ISD::ZERO_EXTEND ||
4546 N0.getOpcode() == ISD::SIGN_EXTEND ||
Chris Lattnerb72773b2006-05-05 22:56:26 +00004547 N0.getOpcode() == ISD::ANY_EXTEND) {
Duncan Sands8e4eb092008-06-08 20:54:56 +00004548 if (N0.getOperand(0).getValueType().bitsLT(VT))
Nate Begeman1d4d4142005-09-01 00:19:25 +00004549 // if the source is smaller than the dest, we still need an extend
Bill Wendling67a67682009-01-30 22:44:24 +00004550 return DAG.getNode(N0.getOpcode(), N->getDebugLoc(), VT,
4551 N0.getOperand(0));
Duncan Sands8e4eb092008-06-08 20:54:56 +00004552 else if (N0.getOperand(0).getValueType().bitsGT(VT))
Nate Begeman1d4d4142005-09-01 00:19:25 +00004553 // if the source is larger than the dest, than we just need the truncate
Bill Wendling67a67682009-01-30 22:44:24 +00004554 return DAG.getNode(ISD::TRUNCATE, N->getDebugLoc(), VT, N0.getOperand(0));
Nate Begeman1d4d4142005-09-01 00:19:25 +00004555 else
4556 // if the source and dest are the same type, we can drop both the extend
Evan Chengd40d03e2010-01-06 19:38:29 +00004557 // and the truncate.
Nate Begeman83e75ec2005-09-06 04:43:02 +00004558 return N0.getOperand(0);
Nate Begeman1d4d4142005-09-01 00:19:25 +00004559 }
Evan Cheng007b69e2007-03-21 20:14:05 +00004560
Chris Lattner2b4c2792007-10-13 06:35:54 +00004561 // See if we can simplify the input to this truncate through knowledge that
Nadav Rotem8c20ec52011-02-24 21:01:34 +00004562 // only the low bits are being used.
4563 // For example "trunc (or (shl x, 8), y)" // -> trunc y
Nadav Rotemfcd96192011-02-27 07:40:43 +00004564 // Currently we only perform this optimization on scalars because vectors
Nadav Rotem8c20ec52011-02-24 21:01:34 +00004565 // may have different active low bits.
4566 if (!VT.isVector()) {
4567 SDValue Shorter =
4568 GetDemandedBits(N0, APInt::getLowBitsSet(N0.getValueSizeInBits(),
4569 VT.getSizeInBits()));
4570 if (Shorter.getNode())
4571 return DAG.getNode(ISD::TRUNCATE, N->getDebugLoc(), VT, Shorter);
4572 }
Nate Begeman3df4d522005-10-12 20:40:40 +00004573 // fold (truncate (load x)) -> (smaller load x)
Evan Cheng007b69e2007-03-21 20:14:05 +00004574 // fold (truncate (srl (load x), c)) -> (smaller load (x+c/evtbits))
Dan Gohman4e39e9d2010-06-24 14:30:44 +00004575 if (!LegalTypes || TLI.isTypeDesirableForOp(N0.getOpcode(), VT)) {
4576 SDValue Reduced = ReduceLoadWidth(N);
4577 if (Reduced.getNode())
4578 return Reduced;
4579 }
4580
4581 // Simplify the operands using demanded-bits information.
4582 if (!VT.isVector() &&
4583 SimplifyDemandedBits(SDValue(N, 0)))
4584 return SDValue(N, 0);
4585
Evan Chenge5b51ac2010-04-17 06:13:15 +00004586 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00004587}
4588
Evan Cheng9bfa03c2008-05-12 23:04:07 +00004589static SDNode *getBuildPairElt(SDNode *N, unsigned i) {
Dan Gohman475871a2008-07-27 21:46:04 +00004590 SDValue Elt = N->getOperand(i);
Evan Cheng9bfa03c2008-05-12 23:04:07 +00004591 if (Elt.getOpcode() != ISD::MERGE_VALUES)
Gabor Greifba36cb52008-08-28 21:40:38 +00004592 return Elt.getNode();
4593 return Elt.getOperand(Elt.getResNo()).getNode();
Evan Cheng9bfa03c2008-05-12 23:04:07 +00004594}
4595
4596/// CombineConsecutiveLoads - build_pair (load, load) -> load
Scott Michelfdc40a02009-02-17 22:15:04 +00004597/// if load locations are consecutive.
Owen Andersone50ed302009-08-10 22:56:29 +00004598SDValue DAGCombiner::CombineConsecutiveLoads(SDNode *N, EVT VT) {
Evan Cheng9bfa03c2008-05-12 23:04:07 +00004599 assert(N->getOpcode() == ISD::BUILD_PAIR);
4600
Nate Begemanabc01992009-06-05 21:37:30 +00004601 LoadSDNode *LD1 = dyn_cast<LoadSDNode>(getBuildPairElt(N, 0));
4602 LoadSDNode *LD2 = dyn_cast<LoadSDNode>(getBuildPairElt(N, 1));
Chris Lattnerfa459012010-09-21 16:08:50 +00004603 if (!LD1 || !LD2 || !ISD::isNON_EXTLoad(LD1) || !LD1->hasOneUse() ||
4604 LD1->getPointerInfo().getAddrSpace() !=
4605 LD2->getPointerInfo().getAddrSpace())
Dan Gohman475871a2008-07-27 21:46:04 +00004606 return SDValue();
Owen Andersone50ed302009-08-10 22:56:29 +00004607 EVT LD1VT = LD1->getValueType(0);
Bill Wendling67a67682009-01-30 22:44:24 +00004608
Evan Cheng9bfa03c2008-05-12 23:04:07 +00004609 if (ISD::isNON_EXTLoad(LD2) &&
4610 LD2->hasOneUse() &&
Duncan Sandsd4b9c172008-06-13 19:07:40 +00004611 // If both are volatile this would reduce the number of volatile loads.
4612 // If one is volatile it might be ok, but play conservative and bail out.
Nate Begemanabc01992009-06-05 21:37:30 +00004613 !LD1->isVolatile() &&
4614 !LD2->isVolatile() &&
Evan Cheng64fa4a92009-12-09 01:36:00 +00004615 DAG.isConsecutiveLoad(LD2, LD1, LD1VT.getSizeInBits()/8, 1)) {
Nate Begemanabc01992009-06-05 21:37:30 +00004616 unsigned Align = LD1->getAlignment();
Dan Gohman6448d912008-09-04 15:39:15 +00004617 unsigned NewAlign = TLI.getTargetData()->
Owen Anderson23b9b192009-08-12 00:36:31 +00004618 getABITypeAlignment(VT.getTypeForEVT(*DAG.getContext()));
Bill Wendling67a67682009-01-30 22:44:24 +00004619
Duncan Sandsd4b9c172008-06-13 19:07:40 +00004620 if (NewAlign <= Align &&
Duncan Sands25cf2272008-11-24 14:53:14 +00004621 (!LegalOperations || TLI.isOperationLegal(ISD::LOAD, VT)))
Nate Begemanabc01992009-06-05 21:37:30 +00004622 return DAG.getLoad(VT, N->getDebugLoc(), LD1->getChain(),
Chris Lattnerfa459012010-09-21 16:08:50 +00004623 LD1->getBasePtr(), LD1->getPointerInfo(),
4624 false, false, Align);
Evan Cheng9bfa03c2008-05-12 23:04:07 +00004625 }
Bill Wendling67a67682009-01-30 22:44:24 +00004626
Dan Gohman475871a2008-07-27 21:46:04 +00004627 return SDValue();
Evan Cheng9bfa03c2008-05-12 23:04:07 +00004628}
4629
Wesley Peckbf17cfa2010-11-23 03:31:01 +00004630SDValue DAGCombiner::visitBITCAST(SDNode *N) {
Dan Gohman475871a2008-07-27 21:46:04 +00004631 SDValue N0 = N->getOperand(0);
Owen Andersone50ed302009-08-10 22:56:29 +00004632 EVT VT = N->getValueType(0);
Chris Lattner94683772005-12-23 05:30:37 +00004633
Dan Gohman7f321562007-06-25 16:23:39 +00004634 // If the input is a BUILD_VECTOR with all constant elements, fold this now.
4635 // Only do this before legalize, since afterward the target may be depending
4636 // on the bitconvert.
4637 // First check to see if this is all constant.
Duncan Sands25cf2272008-11-24 14:53:14 +00004638 if (!LegalTypes &&
Gabor Greifba36cb52008-08-28 21:40:38 +00004639 N0.getOpcode() == ISD::BUILD_VECTOR && N0.getNode()->hasOneUse() &&
Duncan Sands83ec4b62008-06-06 12:08:01 +00004640 VT.isVector()) {
Dan Gohman7f321562007-06-25 16:23:39 +00004641 bool isSimple = true;
4642 for (unsigned i = 0, e = N0.getNumOperands(); i != e; ++i)
4643 if (N0.getOperand(i).getOpcode() != ISD::UNDEF &&
4644 N0.getOperand(i).getOpcode() != ISD::Constant &&
4645 N0.getOperand(i).getOpcode() != ISD::ConstantFP) {
Scott Michelfdc40a02009-02-17 22:15:04 +00004646 isSimple = false;
Dan Gohman7f321562007-06-25 16:23:39 +00004647 break;
4648 }
Scott Michelfdc40a02009-02-17 22:15:04 +00004649
Owen Andersone50ed302009-08-10 22:56:29 +00004650 EVT DestEltVT = N->getValueType(0).getVectorElementType();
Duncan Sands83ec4b62008-06-06 12:08:01 +00004651 assert(!DestEltVT.isVector() &&
Dan Gohman7f321562007-06-25 16:23:39 +00004652 "Element type of vector ValueType must not be vector!");
Bill Wendling67a67682009-01-30 22:44:24 +00004653 if (isSimple)
Wesley Peckbf17cfa2010-11-23 03:31:01 +00004654 return ConstantFoldBITCASTofBUILD_VECTOR(N0.getNode(), DestEltVT);
Dan Gohman7f321562007-06-25 16:23:39 +00004655 }
Scott Michelfdc40a02009-02-17 22:15:04 +00004656
Dan Gohman3dd168d2008-09-05 01:58:21 +00004657 // If the input is a constant, let getNode fold it.
Chris Lattner94683772005-12-23 05:30:37 +00004658 if (isa<ConstantSDNode>(N0) || isa<ConstantFPSDNode>(N0)) {
Wesley Peckbf17cfa2010-11-23 03:31:01 +00004659 SDValue Res = DAG.getNode(ISD::BITCAST, N->getDebugLoc(), VT, N0);
Dan Gohmana407ca12009-08-10 23:15:10 +00004660 if (Res.getNode() != N) {
4661 if (!LegalOperations ||
4662 TLI.isOperationLegal(Res.getNode()->getOpcode(), VT))
4663 return Res;
4664
4665 // Folding it resulted in an illegal node, and it's too late to
4666 // do that. Clean up the old node and forego the transformation.
4667 // Ideally this won't happen very often, because instcombine
4668 // and the earlier dagcombine runs (where illegal nodes are
4669 // permitted) should have folded most of them already.
4670 DAG.DeleteNode(Res.getNode());
4671 }
Chris Lattner94683772005-12-23 05:30:37 +00004672 }
Scott Michelfdc40a02009-02-17 22:15:04 +00004673
Bill Wendling67a67682009-01-30 22:44:24 +00004674 // (conv (conv x, t1), t2) -> (conv x, t2)
Wesley Peckbf17cfa2010-11-23 03:31:01 +00004675 if (N0.getOpcode() == ISD::BITCAST)
4676 return DAG.getNode(ISD::BITCAST, N->getDebugLoc(), VT,
Bill Wendling67a67682009-01-30 22:44:24 +00004677 N0.getOperand(0));
Chris Lattner6258fb22006-04-02 02:53:43 +00004678
Chris Lattner57104102005-12-23 05:44:41 +00004679 // fold (conv (load x)) -> (load (conv*)x)
Evan Cheng513da432007-10-06 08:19:55 +00004680 // If the resultant load doesn't need a higher alignment than the original!
Gabor Greifba36cb52008-08-28 21:40:38 +00004681 if (ISD::isNormalLoad(N0.getNode()) && N0.hasOneUse() &&
Duncan Sandsd4b9c172008-06-13 19:07:40 +00004682 // Do not change the width of a volatile load.
4683 !cast<LoadSDNode>(N0)->isVolatile() &&
Duncan Sands25cf2272008-11-24 14:53:14 +00004684 (!LegalOperations || TLI.isOperationLegal(ISD::LOAD, VT))) {
Evan Cheng466685d2006-10-09 20:57:25 +00004685 LoadSDNode *LN0 = cast<LoadSDNode>(N0);
Dan Gohman6448d912008-09-04 15:39:15 +00004686 unsigned Align = TLI.getTargetData()->
Owen Anderson23b9b192009-08-12 00:36:31 +00004687 getABITypeAlignment(VT.getTypeForEVT(*DAG.getContext()));
Evan Cheng59d5b682007-05-07 21:27:48 +00004688 unsigned OrigAlign = LN0->getAlignment();
Bill Wendling67a67682009-01-30 22:44:24 +00004689
Evan Cheng59d5b682007-05-07 21:27:48 +00004690 if (Align <= OrigAlign) {
Bill Wendling67a67682009-01-30 22:44:24 +00004691 SDValue Load = DAG.getLoad(VT, N->getDebugLoc(), LN0->getChain(),
Chris Lattnerfa459012010-09-21 16:08:50 +00004692 LN0->getBasePtr(), LN0->getPointerInfo(),
David Greene1e559442010-02-15 17:00:31 +00004693 LN0->isVolatile(), LN0->isNonTemporal(),
4694 OrigAlign);
Evan Cheng59d5b682007-05-07 21:27:48 +00004695 AddToWorkList(N);
Gabor Greif12632d22008-08-30 19:29:20 +00004696 CombineTo(N0.getNode(),
Wesley Peckbf17cfa2010-11-23 03:31:01 +00004697 DAG.getNode(ISD::BITCAST, N0.getDebugLoc(),
Bill Wendling67a67682009-01-30 22:44:24 +00004698 N0.getValueType(), Load),
Evan Cheng59d5b682007-05-07 21:27:48 +00004699 Load.getValue(1));
4700 return Load;
4701 }
Chris Lattner57104102005-12-23 05:44:41 +00004702 }
Duncan Sandsd4b9c172008-06-13 19:07:40 +00004703
Bill Wendling67a67682009-01-30 22:44:24 +00004704 // fold (bitconvert (fneg x)) -> (xor (bitconvert x), signbit)
4705 // fold (bitconvert (fabs x)) -> (and (bitconvert x), (not signbit))
Chris Lattner3bd39d42008-01-27 17:42:27 +00004706 // This often reduces constant pool loads.
4707 if ((N0.getOpcode() == ISD::FNEG || N0.getOpcode() == ISD::FABS) &&
Gabor Greifba36cb52008-08-28 21:40:38 +00004708 N0.getNode()->hasOneUse() && VT.isInteger() && !VT.isVector()) {
Wesley Peckbf17cfa2010-11-23 03:31:01 +00004709 SDValue NewConv = DAG.getNode(ISD::BITCAST, N0.getDebugLoc(), VT,
Bill Wendling67a67682009-01-30 22:44:24 +00004710 N0.getOperand(0));
Gabor Greifba36cb52008-08-28 21:40:38 +00004711 AddToWorkList(NewConv.getNode());
Scott Michelfdc40a02009-02-17 22:15:04 +00004712
Duncan Sands83ec4b62008-06-06 12:08:01 +00004713 APInt SignBit = APInt::getSignBit(VT.getSizeInBits());
Chris Lattner3bd39d42008-01-27 17:42:27 +00004714 if (N0.getOpcode() == ISD::FNEG)
Bill Wendling67a67682009-01-30 22:44:24 +00004715 return DAG.getNode(ISD::XOR, N->getDebugLoc(), VT,
4716 NewConv, DAG.getConstant(SignBit, VT));
Chris Lattner3bd39d42008-01-27 17:42:27 +00004717 assert(N0.getOpcode() == ISD::FABS);
Bill Wendling67a67682009-01-30 22:44:24 +00004718 return DAG.getNode(ISD::AND, N->getDebugLoc(), VT,
4719 NewConv, DAG.getConstant(~SignBit, VT));
Chris Lattner3bd39d42008-01-27 17:42:27 +00004720 }
Scott Michelfdc40a02009-02-17 22:15:04 +00004721
Bill Wendling67a67682009-01-30 22:44:24 +00004722 // fold (bitconvert (fcopysign cst, x)) ->
4723 // (or (and (bitconvert x), sign), (and cst, (not sign)))
4724 // Note that we don't handle (copysign x, cst) because this can always be
4725 // folded to an fneg or fabs.
Gabor Greifba36cb52008-08-28 21:40:38 +00004726 if (N0.getOpcode() == ISD::FCOPYSIGN && N0.getNode()->hasOneUse() &&
Chris Lattnerf32aac32008-01-27 23:32:17 +00004727 isa<ConstantFPSDNode>(N0.getOperand(0)) &&
Duncan Sands83ec4b62008-06-06 12:08:01 +00004728 VT.isInteger() && !VT.isVector()) {
4729 unsigned OrigXWidth = N0.getOperand(1).getValueType().getSizeInBits();
Owen Anderson23b9b192009-08-12 00:36:31 +00004730 EVT IntXVT = EVT::getIntegerVT(*DAG.getContext(), OrigXWidth);
Chris Lattner2392ae72010-04-15 04:48:01 +00004731 if (isTypeLegal(IntXVT)) {
Wesley Peckbf17cfa2010-11-23 03:31:01 +00004732 SDValue X = DAG.getNode(ISD::BITCAST, N0.getDebugLoc(),
Bill Wendling67a67682009-01-30 22:44:24 +00004733 IntXVT, N0.getOperand(1));
Duncan Sands25cf2272008-11-24 14:53:14 +00004734 AddToWorkList(X.getNode());
Chris Lattner3bd39d42008-01-27 17:42:27 +00004735
Duncan Sands25cf2272008-11-24 14:53:14 +00004736 // If X has a different width than the result/lhs, sext it or truncate it.
4737 unsigned VTWidth = VT.getSizeInBits();
4738 if (OrigXWidth < VTWidth) {
Bill Wendling9729c5a2009-01-31 03:12:48 +00004739 X = DAG.getNode(ISD::SIGN_EXTEND, N->getDebugLoc(), VT, X);
Duncan Sands25cf2272008-11-24 14:53:14 +00004740 AddToWorkList(X.getNode());
4741 } else if (OrigXWidth > VTWidth) {
4742 // To get the sign bit in the right place, we have to shift it right
4743 // before truncating.
Bill Wendling9729c5a2009-01-31 03:12:48 +00004744 X = DAG.getNode(ISD::SRL, X.getDebugLoc(),
Bill Wendling67a67682009-01-30 22:44:24 +00004745 X.getValueType(), X,
Duncan Sands25cf2272008-11-24 14:53:14 +00004746 DAG.getConstant(OrigXWidth-VTWidth, X.getValueType()));
4747 AddToWorkList(X.getNode());
Bill Wendling9729c5a2009-01-31 03:12:48 +00004748 X = DAG.getNode(ISD::TRUNCATE, X.getDebugLoc(), VT, X);
Duncan Sands25cf2272008-11-24 14:53:14 +00004749 AddToWorkList(X.getNode());
4750 }
Scott Michelfdc40a02009-02-17 22:15:04 +00004751
Duncan Sands25cf2272008-11-24 14:53:14 +00004752 APInt SignBit = APInt::getSignBit(VT.getSizeInBits());
Bill Wendling9729c5a2009-01-31 03:12:48 +00004753 X = DAG.getNode(ISD::AND, X.getDebugLoc(), VT,
Bill Wendling67a67682009-01-30 22:44:24 +00004754 X, DAG.getConstant(SignBit, VT));
Duncan Sands25cf2272008-11-24 14:53:14 +00004755 AddToWorkList(X.getNode());
Chris Lattner3bd39d42008-01-27 17:42:27 +00004756
Wesley Peckbf17cfa2010-11-23 03:31:01 +00004757 SDValue Cst = DAG.getNode(ISD::BITCAST, N0.getDebugLoc(),
Bill Wendling67a67682009-01-30 22:44:24 +00004758 VT, N0.getOperand(0));
Bill Wendling9729c5a2009-01-31 03:12:48 +00004759 Cst = DAG.getNode(ISD::AND, Cst.getDebugLoc(), VT,
Bill Wendling67a67682009-01-30 22:44:24 +00004760 Cst, DAG.getConstant(~SignBit, VT));
Duncan Sands25cf2272008-11-24 14:53:14 +00004761 AddToWorkList(Cst.getNode());
Chris Lattner3bd39d42008-01-27 17:42:27 +00004762
Bill Wendling67a67682009-01-30 22:44:24 +00004763 return DAG.getNode(ISD::OR, N->getDebugLoc(), VT, X, Cst);
Duncan Sands25cf2272008-11-24 14:53:14 +00004764 }
Chris Lattner3bd39d42008-01-27 17:42:27 +00004765 }
Evan Cheng9bfa03c2008-05-12 23:04:07 +00004766
Scott Michelfdc40a02009-02-17 22:15:04 +00004767 // bitconvert(build_pair(ld, ld)) -> ld iff load locations are consecutive.
Evan Cheng9bfa03c2008-05-12 23:04:07 +00004768 if (N0.getOpcode() == ISD::BUILD_PAIR) {
Gabor Greifba36cb52008-08-28 21:40:38 +00004769 SDValue CombineLD = CombineConsecutiveLoads(N0.getNode(), VT);
4770 if (CombineLD.getNode())
Evan Cheng9bfa03c2008-05-12 23:04:07 +00004771 return CombineLD;
4772 }
Scott Michelfdc40a02009-02-17 22:15:04 +00004773
Dan Gohman475871a2008-07-27 21:46:04 +00004774 return SDValue();
Chris Lattner94683772005-12-23 05:30:37 +00004775}
4776
Dan Gohman475871a2008-07-27 21:46:04 +00004777SDValue DAGCombiner::visitBUILD_PAIR(SDNode *N) {
Owen Andersone50ed302009-08-10 22:56:29 +00004778 EVT VT = N->getValueType(0);
Evan Cheng9bfa03c2008-05-12 23:04:07 +00004779 return CombineConsecutiveLoads(N, VT);
4780}
4781
Wesley Peckbf17cfa2010-11-23 03:31:01 +00004782/// ConstantFoldBITCASTofBUILD_VECTOR - We know that BV is a build_vector
Scott Michelfdc40a02009-02-17 22:15:04 +00004783/// node with Constant, ConstantFP or Undef operands. DstEltVT indicates the
Chris Lattner6258fb22006-04-02 02:53:43 +00004784/// destination element value type.
Dan Gohman475871a2008-07-27 21:46:04 +00004785SDValue DAGCombiner::
Wesley Peckbf17cfa2010-11-23 03:31:01 +00004786ConstantFoldBITCASTofBUILD_VECTOR(SDNode *BV, EVT DstEltVT) {
Owen Andersone50ed302009-08-10 22:56:29 +00004787 EVT SrcEltVT = BV->getValueType(0).getVectorElementType();
Scott Michelfdc40a02009-02-17 22:15:04 +00004788
Chris Lattner6258fb22006-04-02 02:53:43 +00004789 // If this is already the right type, we're done.
Dan Gohman475871a2008-07-27 21:46:04 +00004790 if (SrcEltVT == DstEltVT) return SDValue(BV, 0);
Scott Michelfdc40a02009-02-17 22:15:04 +00004791
Duncan Sands83ec4b62008-06-06 12:08:01 +00004792 unsigned SrcBitSize = SrcEltVT.getSizeInBits();
4793 unsigned DstBitSize = DstEltVT.getSizeInBits();
Scott Michelfdc40a02009-02-17 22:15:04 +00004794
Chris Lattner6258fb22006-04-02 02:53:43 +00004795 // If this is a conversion of N elements of one type to N elements of another
4796 // type, convert each element. This handles FP<->INT cases.
4797 if (SrcBitSize == DstBitSize) {
Nate Begemane0efc212010-07-27 18:02:18 +00004798 EVT VT = EVT::getVectorVT(*DAG.getContext(), DstEltVT,
4799 BV->getValueType(0).getVectorNumElements());
4800
4801 // Due to the FP element handling below calling this routine recursively,
4802 // we can end up with a scalar-to-vector node here.
4803 if (BV->getOpcode() == ISD::SCALAR_TO_VECTOR)
Wesley Peckbf17cfa2010-11-23 03:31:01 +00004804 return DAG.getNode(ISD::SCALAR_TO_VECTOR, BV->getDebugLoc(), VT,
4805 DAG.getNode(ISD::BITCAST, BV->getDebugLoc(),
Nate Begemane0efc212010-07-27 18:02:18 +00004806 DstEltVT, BV->getOperand(0)));
Wesley Peckbf17cfa2010-11-23 03:31:01 +00004807
Dan Gohman475871a2008-07-27 21:46:04 +00004808 SmallVector<SDValue, 8> Ops;
Dan Gohman7f321562007-06-25 16:23:39 +00004809 for (unsigned i = 0, e = BV->getNumOperands(); i != e; ++i) {
Bob Wilsonb1303d02009-04-13 22:05:19 +00004810 SDValue Op = BV->getOperand(i);
4811 // If the vector element type is not legal, the BUILD_VECTOR operands
4812 // are promoted and implicitly truncated. Make that explicit here.
Bob Wilsonc8851652009-04-20 17:27:09 +00004813 if (Op.getValueType() != SrcEltVT)
4814 Op = DAG.getNode(ISD::TRUNCATE, BV->getDebugLoc(), SrcEltVT, Op);
Wesley Peckbf17cfa2010-11-23 03:31:01 +00004815 Ops.push_back(DAG.getNode(ISD::BITCAST, BV->getDebugLoc(),
Bob Wilsonb1303d02009-04-13 22:05:19 +00004816 DstEltVT, Op));
Gabor Greifba36cb52008-08-28 21:40:38 +00004817 AddToWorkList(Ops.back().getNode());
Chris Lattner3e104b12006-04-08 04:15:24 +00004818 }
Evan Chenga87008d2009-02-25 22:49:59 +00004819 return DAG.getNode(ISD::BUILD_VECTOR, BV->getDebugLoc(), VT,
4820 &Ops[0], Ops.size());
Chris Lattner6258fb22006-04-02 02:53:43 +00004821 }
Scott Michelfdc40a02009-02-17 22:15:04 +00004822
Chris Lattner6258fb22006-04-02 02:53:43 +00004823 // Otherwise, we're growing or shrinking the elements. To avoid having to
4824 // handle annoying details of growing/shrinking FP values, we convert them to
4825 // int first.
Duncan Sands83ec4b62008-06-06 12:08:01 +00004826 if (SrcEltVT.isFloatingPoint()) {
Chris Lattner6258fb22006-04-02 02:53:43 +00004827 // Convert the input float vector to a int vector where the elements are the
4828 // same sizes.
Owen Anderson825b72b2009-08-11 20:47:22 +00004829 assert((SrcEltVT == MVT::f32 || SrcEltVT == MVT::f64) && "Unknown FP VT!");
Owen Anderson23b9b192009-08-12 00:36:31 +00004830 EVT IntVT = EVT::getIntegerVT(*DAG.getContext(), SrcEltVT.getSizeInBits());
Wesley Peckbf17cfa2010-11-23 03:31:01 +00004831 BV = ConstantFoldBITCASTofBUILD_VECTOR(BV, IntVT).getNode();
Chris Lattner6258fb22006-04-02 02:53:43 +00004832 SrcEltVT = IntVT;
4833 }
Scott Michelfdc40a02009-02-17 22:15:04 +00004834
Chris Lattner6258fb22006-04-02 02:53:43 +00004835 // Now we know the input is an integer vector. If the output is a FP type,
4836 // convert to integer first, then to FP of the right size.
Duncan Sands83ec4b62008-06-06 12:08:01 +00004837 if (DstEltVT.isFloatingPoint()) {
Owen Anderson825b72b2009-08-11 20:47:22 +00004838 assert((DstEltVT == MVT::f32 || DstEltVT == MVT::f64) && "Unknown FP VT!");
Owen Anderson23b9b192009-08-12 00:36:31 +00004839 EVT TmpVT = EVT::getIntegerVT(*DAG.getContext(), DstEltVT.getSizeInBits());
Wesley Peckbf17cfa2010-11-23 03:31:01 +00004840 SDNode *Tmp = ConstantFoldBITCASTofBUILD_VECTOR(BV, TmpVT).getNode();
Scott Michelfdc40a02009-02-17 22:15:04 +00004841
Chris Lattner6258fb22006-04-02 02:53:43 +00004842 // Next, convert to FP elements of the same size.
Wesley Peckbf17cfa2010-11-23 03:31:01 +00004843 return ConstantFoldBITCASTofBUILD_VECTOR(Tmp, DstEltVT);
Chris Lattner6258fb22006-04-02 02:53:43 +00004844 }
Scott Michelfdc40a02009-02-17 22:15:04 +00004845
Chris Lattner6258fb22006-04-02 02:53:43 +00004846 // Okay, we know the src/dst types are both integers of differing types.
4847 // Handling growing first.
Duncan Sands83ec4b62008-06-06 12:08:01 +00004848 assert(SrcEltVT.isInteger() && DstEltVT.isInteger());
Chris Lattner6258fb22006-04-02 02:53:43 +00004849 if (SrcBitSize < DstBitSize) {
4850 unsigned NumInputsPerOutput = DstBitSize/SrcBitSize;
Scott Michelfdc40a02009-02-17 22:15:04 +00004851
Dan Gohman475871a2008-07-27 21:46:04 +00004852 SmallVector<SDValue, 8> Ops;
Dan Gohman7f321562007-06-25 16:23:39 +00004853 for (unsigned i = 0, e = BV->getNumOperands(); i != e;
Chris Lattner6258fb22006-04-02 02:53:43 +00004854 i += NumInputsPerOutput) {
4855 bool isLE = TLI.isLittleEndian();
Dan Gohman220a8232008-03-03 23:51:38 +00004856 APInt NewBits = APInt(DstBitSize, 0);
Chris Lattner6258fb22006-04-02 02:53:43 +00004857 bool EltIsUndef = true;
4858 for (unsigned j = 0; j != NumInputsPerOutput; ++j) {
4859 // Shift the previously computed bits over.
4860 NewBits <<= SrcBitSize;
Dan Gohman475871a2008-07-27 21:46:04 +00004861 SDValue Op = BV->getOperand(i+ (isLE ? (NumInputsPerOutput-j-1) : j));
Chris Lattner6258fb22006-04-02 02:53:43 +00004862 if (Op.getOpcode() == ISD::UNDEF) continue;
4863 EltIsUndef = false;
Scott Michelfdc40a02009-02-17 22:15:04 +00004864
Jay Foad40f8f622010-12-07 08:25:19 +00004865 NewBits |= cast<ConstantSDNode>(Op)->getAPIntValue().
Dan Gohman58c25872010-04-12 02:24:01 +00004866 zextOrTrunc(SrcBitSize).zext(DstBitSize);
Chris Lattner6258fb22006-04-02 02:53:43 +00004867 }
Scott Michelfdc40a02009-02-17 22:15:04 +00004868
Chris Lattner6258fb22006-04-02 02:53:43 +00004869 if (EltIsUndef)
Dale Johannesene8d72302009-02-06 23:05:02 +00004870 Ops.push_back(DAG.getUNDEF(DstEltVT));
Chris Lattner6258fb22006-04-02 02:53:43 +00004871 else
4872 Ops.push_back(DAG.getConstant(NewBits, DstEltVT));
4873 }
4874
Owen Anderson23b9b192009-08-12 00:36:31 +00004875 EVT VT = EVT::getVectorVT(*DAG.getContext(), DstEltVT, Ops.size());
Evan Chenga87008d2009-02-25 22:49:59 +00004876 return DAG.getNode(ISD::BUILD_VECTOR, BV->getDebugLoc(), VT,
4877 &Ops[0], Ops.size());
Chris Lattner6258fb22006-04-02 02:53:43 +00004878 }
Scott Michelfdc40a02009-02-17 22:15:04 +00004879
Chris Lattner6258fb22006-04-02 02:53:43 +00004880 // Finally, this must be the case where we are shrinking elements: each input
4881 // turns into multiple outputs.
Evan Chengefec7512008-02-18 23:04:32 +00004882 bool isS2V = ISD::isScalarToVector(BV);
Chris Lattner6258fb22006-04-02 02:53:43 +00004883 unsigned NumOutputsPerInput = SrcBitSize/DstBitSize;
Owen Anderson23b9b192009-08-12 00:36:31 +00004884 EVT VT = EVT::getVectorVT(*DAG.getContext(), DstEltVT,
4885 NumOutputsPerInput*BV->getNumOperands());
Dan Gohman475871a2008-07-27 21:46:04 +00004886 SmallVector<SDValue, 8> Ops;
Bill Wendlingb0162f52009-01-30 22:53:48 +00004887
Dan Gohman7f321562007-06-25 16:23:39 +00004888 for (unsigned i = 0, e = BV->getNumOperands(); i != e; ++i) {
Chris Lattner6258fb22006-04-02 02:53:43 +00004889 if (BV->getOperand(i).getOpcode() == ISD::UNDEF) {
4890 for (unsigned j = 0; j != NumOutputsPerInput; ++j)
Dale Johannesene8d72302009-02-06 23:05:02 +00004891 Ops.push_back(DAG.getUNDEF(DstEltVT));
Chris Lattner6258fb22006-04-02 02:53:43 +00004892 continue;
4893 }
Bill Wendlingb0162f52009-01-30 22:53:48 +00004894
Jay Foad40f8f622010-12-07 08:25:19 +00004895 APInt OpVal = cast<ConstantSDNode>(BV->getOperand(i))->
4896 getAPIntValue().zextOrTrunc(SrcBitSize);
Bill Wendlingb0162f52009-01-30 22:53:48 +00004897
Chris Lattner6258fb22006-04-02 02:53:43 +00004898 for (unsigned j = 0; j != NumOutputsPerInput; ++j) {
Jay Foad40f8f622010-12-07 08:25:19 +00004899 APInt ThisVal = OpVal.trunc(DstBitSize);
Chris Lattner6258fb22006-04-02 02:53:43 +00004900 Ops.push_back(DAG.getConstant(ThisVal, DstEltVT));
Jay Foad40f8f622010-12-07 08:25:19 +00004901 if (isS2V && i == 0 && j == 0 && ThisVal.zext(SrcBitSize) == OpVal)
Evan Chengefec7512008-02-18 23:04:32 +00004902 // Simply turn this into a SCALAR_TO_VECTOR of the new type.
Bill Wendlingb0162f52009-01-30 22:53:48 +00004903 return DAG.getNode(ISD::SCALAR_TO_VECTOR, BV->getDebugLoc(), VT,
4904 Ops[0]);
Dan Gohman220a8232008-03-03 23:51:38 +00004905 OpVal = OpVal.lshr(DstBitSize);
Chris Lattner6258fb22006-04-02 02:53:43 +00004906 }
4907
4908 // For big endian targets, swap the order of the pieces of each element.
Duncan Sands0753fc12008-02-11 10:37:04 +00004909 if (TLI.isBigEndian())
Chris Lattner6258fb22006-04-02 02:53:43 +00004910 std::reverse(Ops.end()-NumOutputsPerInput, Ops.end());
4911 }
Bill Wendlingb0162f52009-01-30 22:53:48 +00004912
Evan Chenga87008d2009-02-25 22:49:59 +00004913 return DAG.getNode(ISD::BUILD_VECTOR, BV->getDebugLoc(), VT,
4914 &Ops[0], Ops.size());
Chris Lattner6258fb22006-04-02 02:53:43 +00004915}
4916
Dan Gohman475871a2008-07-27 21:46:04 +00004917SDValue DAGCombiner::visitFADD(SDNode *N) {
4918 SDValue N0 = N->getOperand(0);
4919 SDValue N1 = N->getOperand(1);
Nate Begemana0e221d2005-10-18 00:28:13 +00004920 ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(N0);
4921 ConstantFPSDNode *N1CFP = dyn_cast<ConstantFPSDNode>(N1);
Owen Andersone50ed302009-08-10 22:56:29 +00004922 EVT VT = N->getValueType(0);
Scott Michelfdc40a02009-02-17 22:15:04 +00004923
Dan Gohman7f321562007-06-25 16:23:39 +00004924 // fold vector ops
Duncan Sands83ec4b62008-06-06 12:08:01 +00004925 if (VT.isVector()) {
Dan Gohman475871a2008-07-27 21:46:04 +00004926 SDValue FoldedVOp = SimplifyVBinOp(N);
Gabor Greifba36cb52008-08-28 21:40:38 +00004927 if (FoldedVOp.getNode()) return FoldedVOp;
Dan Gohman05d92fe2007-07-13 20:03:40 +00004928 }
Scott Michelfdc40a02009-02-17 22:15:04 +00004929
Bill Wendlingb0162f52009-01-30 22:53:48 +00004930 // fold (fadd c1, c2) -> (fadd c1, c2)
Owen Anderson825b72b2009-08-11 20:47:22 +00004931 if (N0CFP && N1CFP && VT != MVT::ppcf128)
Bill Wendlingb0162f52009-01-30 22:53:48 +00004932 return DAG.getNode(ISD::FADD, N->getDebugLoc(), VT, N0, N1);
Nate Begemana0e221d2005-10-18 00:28:13 +00004933 // canonicalize constant to RHS
4934 if (N0CFP && !N1CFP)
Bill Wendlingb0162f52009-01-30 22:53:48 +00004935 return DAG.getNode(ISD::FADD, N->getDebugLoc(), VT, N1, N0);
4936 // fold (fadd A, 0) -> A
Dan Gohman760f86f2009-01-22 21:58:43 +00004937 if (UnsafeFPMath && N1CFP && N1CFP->getValueAPF().isZero())
4938 return N0;
Bill Wendlingb0162f52009-01-30 22:53:48 +00004939 // fold (fadd A, (fneg B)) -> (fsub A, B)
Duncan Sands25cf2272008-11-24 14:53:14 +00004940 if (isNegatibleForFree(N1, LegalOperations) == 2)
Bill Wendlingb0162f52009-01-30 22:53:48 +00004941 return DAG.getNode(ISD::FSUB, N->getDebugLoc(), VT, N0,
Duncan Sands25cf2272008-11-24 14:53:14 +00004942 GetNegatedExpression(N1, DAG, LegalOperations));
Bill Wendlingb0162f52009-01-30 22:53:48 +00004943 // fold (fadd (fneg A), B) -> (fsub B, A)
Duncan Sands25cf2272008-11-24 14:53:14 +00004944 if (isNegatibleForFree(N0, LegalOperations) == 2)
Bill Wendlingb0162f52009-01-30 22:53:48 +00004945 return DAG.getNode(ISD::FSUB, N->getDebugLoc(), VT, N1,
Duncan Sands25cf2272008-11-24 14:53:14 +00004946 GetNegatedExpression(N0, DAG, LegalOperations));
Scott Michelfdc40a02009-02-17 22:15:04 +00004947
Chris Lattnerddae4bd2007-01-08 23:04:05 +00004948 // If allowed, fold (fadd (fadd x, c1), c2) -> (fadd x, (fadd c1, c2))
4949 if (UnsafeFPMath && N1CFP && N0.getOpcode() == ISD::FADD &&
Gabor Greifba36cb52008-08-28 21:40:38 +00004950 N0.getNode()->hasOneUse() && isa<ConstantFPSDNode>(N0.getOperand(1)))
Bill Wendlingb0162f52009-01-30 22:53:48 +00004951 return DAG.getNode(ISD::FADD, N->getDebugLoc(), VT, N0.getOperand(0),
Bill Wendlingfc4b6772009-02-01 11:19:36 +00004952 DAG.getNode(ISD::FADD, N->getDebugLoc(), VT,
4953 N0.getOperand(1), N1));
Scott Michelfdc40a02009-02-17 22:15:04 +00004954
Dan Gohman475871a2008-07-27 21:46:04 +00004955 return SDValue();
Chris Lattner01b3d732005-09-28 22:28:18 +00004956}
4957
Dan Gohman475871a2008-07-27 21:46:04 +00004958SDValue DAGCombiner::visitFSUB(SDNode *N) {
4959 SDValue N0 = N->getOperand(0);
4960 SDValue N1 = N->getOperand(1);
Nate Begemana0e221d2005-10-18 00:28:13 +00004961 ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(N0);
4962 ConstantFPSDNode *N1CFP = dyn_cast<ConstantFPSDNode>(N1);
Owen Andersone50ed302009-08-10 22:56:29 +00004963 EVT VT = N->getValueType(0);
Scott Michelfdc40a02009-02-17 22:15:04 +00004964
Dan Gohman7f321562007-06-25 16:23:39 +00004965 // fold vector ops
Duncan Sands83ec4b62008-06-06 12:08:01 +00004966 if (VT.isVector()) {
Dan Gohman475871a2008-07-27 21:46:04 +00004967 SDValue FoldedVOp = SimplifyVBinOp(N);
Gabor Greifba36cb52008-08-28 21:40:38 +00004968 if (FoldedVOp.getNode()) return FoldedVOp;
Dan Gohman05d92fe2007-07-13 20:03:40 +00004969 }
Scott Michelfdc40a02009-02-17 22:15:04 +00004970
Nate Begemana0e221d2005-10-18 00:28:13 +00004971 // fold (fsub c1, c2) -> c1-c2
Owen Anderson825b72b2009-08-11 20:47:22 +00004972 if (N0CFP && N1CFP && VT != MVT::ppcf128)
Bill Wendlingfc4b6772009-02-01 11:19:36 +00004973 return DAG.getNode(ISD::FSUB, N->getDebugLoc(), VT, N0, N1);
Bill Wendlingb0162f52009-01-30 22:53:48 +00004974 // fold (fsub A, 0) -> A
Dan Gohmana90c8e62009-01-23 19:10:37 +00004975 if (UnsafeFPMath && N1CFP && N1CFP->getValueAPF().isZero())
4976 return N0;
Bill Wendlingb0162f52009-01-30 22:53:48 +00004977 // fold (fsub 0, B) -> -B
Dale Johannesenc4dd3c32007-08-31 23:34:27 +00004978 if (UnsafeFPMath && N0CFP && N0CFP->getValueAPF().isZero()) {
Duncan Sands25cf2272008-11-24 14:53:14 +00004979 if (isNegatibleForFree(N1, LegalOperations))
4980 return GetNegatedExpression(N1, DAG, LegalOperations);
Dan Gohman760f86f2009-01-22 21:58:43 +00004981 if (!LegalOperations || TLI.isOperationLegal(ISD::FNEG, VT))
Bill Wendlingb0162f52009-01-30 22:53:48 +00004982 return DAG.getNode(ISD::FNEG, N->getDebugLoc(), VT, N1);
Dan Gohman23ff1822007-07-02 15:48:56 +00004983 }
Bill Wendlingb0162f52009-01-30 22:53:48 +00004984 // fold (fsub A, (fneg B)) -> (fadd A, B)
Duncan Sands25cf2272008-11-24 14:53:14 +00004985 if (isNegatibleForFree(N1, LegalOperations))
Bill Wendlingb0162f52009-01-30 22:53:48 +00004986 return DAG.getNode(ISD::FADD, N->getDebugLoc(), VT, N0,
Duncan Sands25cf2272008-11-24 14:53:14 +00004987 GetNegatedExpression(N1, DAG, LegalOperations));
Scott Michelfdc40a02009-02-17 22:15:04 +00004988
Dan Gohman475871a2008-07-27 21:46:04 +00004989 return SDValue();
Chris Lattner01b3d732005-09-28 22:28:18 +00004990}
4991
Dan Gohman475871a2008-07-27 21:46:04 +00004992SDValue DAGCombiner::visitFMUL(SDNode *N) {
4993 SDValue N0 = N->getOperand(0);
4994 SDValue N1 = N->getOperand(1);
Nate Begeman11af4ea2005-10-17 20:40:11 +00004995 ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(N0);
4996 ConstantFPSDNode *N1CFP = dyn_cast<ConstantFPSDNode>(N1);
Owen Andersone50ed302009-08-10 22:56:29 +00004997 EVT VT = N->getValueType(0);
Chris Lattner01b3d732005-09-28 22:28:18 +00004998
Dan Gohman7f321562007-06-25 16:23:39 +00004999 // fold vector ops
Duncan Sands83ec4b62008-06-06 12:08:01 +00005000 if (VT.isVector()) {
Dan Gohman475871a2008-07-27 21:46:04 +00005001 SDValue FoldedVOp = SimplifyVBinOp(N);
Gabor Greifba36cb52008-08-28 21:40:38 +00005002 if (FoldedVOp.getNode()) return FoldedVOp;
Dan Gohman05d92fe2007-07-13 20:03:40 +00005003 }
Scott Michelfdc40a02009-02-17 22:15:04 +00005004
Nate Begeman11af4ea2005-10-17 20:40:11 +00005005 // fold (fmul c1, c2) -> c1*c2
Owen Anderson825b72b2009-08-11 20:47:22 +00005006 if (N0CFP && N1CFP && VT != MVT::ppcf128)
Bill Wendlinga03e74b2009-01-30 22:57:07 +00005007 return DAG.getNode(ISD::FMUL, N->getDebugLoc(), VT, N0, N1);
Nate Begeman11af4ea2005-10-17 20:40:11 +00005008 // canonicalize constant to RHS
Nate Begemana0e221d2005-10-18 00:28:13 +00005009 if (N0CFP && !N1CFP)
Bill Wendlinga03e74b2009-01-30 22:57:07 +00005010 return DAG.getNode(ISD::FMUL, N->getDebugLoc(), VT, N1, N0);
5011 // fold (fmul A, 0) -> 0
Dan Gohman760f86f2009-01-22 21:58:43 +00005012 if (UnsafeFPMath && N1CFP && N1CFP->getValueAPF().isZero())
5013 return N1;
Dan Gohman77b81fe2009-06-04 17:12:12 +00005014 // fold (fmul A, 0) -> 0, vector edition.
5015 if (UnsafeFPMath && ISD::isBuildVectorAllZeros(N1.getNode()))
5016 return N1;
Nate Begeman11af4ea2005-10-17 20:40:11 +00005017 // fold (fmul X, 2.0) -> (fadd X, X)
5018 if (N1CFP && N1CFP->isExactlyValue(+2.0))
Bill Wendlinga03e74b2009-01-30 22:57:07 +00005019 return DAG.getNode(ISD::FADD, N->getDebugLoc(), VT, N0, N0);
Dan Gohmaneb1fedc2009-08-10 16:50:32 +00005020 // fold (fmul X, -1.0) -> (fneg X)
Chris Lattner29446522007-05-14 22:04:50 +00005021 if (N1CFP && N1CFP->isExactlyValue(-1.0))
Dan Gohman760f86f2009-01-22 21:58:43 +00005022 if (!LegalOperations || TLI.isOperationLegal(ISD::FNEG, VT))
Bill Wendlinga03e74b2009-01-30 22:57:07 +00005023 return DAG.getNode(ISD::FNEG, N->getDebugLoc(), VT, N0);
Scott Michelfdc40a02009-02-17 22:15:04 +00005024
Bill Wendlinga03e74b2009-01-30 22:57:07 +00005025 // fold (fmul (fneg X), (fneg Y)) -> (fmul X, Y)
Duncan Sands25cf2272008-11-24 14:53:14 +00005026 if (char LHSNeg = isNegatibleForFree(N0, LegalOperations)) {
5027 if (char RHSNeg = isNegatibleForFree(N1, LegalOperations)) {
Chris Lattner29446522007-05-14 22:04:50 +00005028 // Both can be negated for free, check to see if at least one is cheaper
5029 // negated.
5030 if (LHSNeg == 2 || RHSNeg == 2)
Bill Wendlinga03e74b2009-01-30 22:57:07 +00005031 return DAG.getNode(ISD::FMUL, N->getDebugLoc(), VT,
Duncan Sands25cf2272008-11-24 14:53:14 +00005032 GetNegatedExpression(N0, DAG, LegalOperations),
5033 GetNegatedExpression(N1, DAG, LegalOperations));
Chris Lattner29446522007-05-14 22:04:50 +00005034 }
5035 }
Scott Michelfdc40a02009-02-17 22:15:04 +00005036
Chris Lattnerddae4bd2007-01-08 23:04:05 +00005037 // If allowed, fold (fmul (fmul x, c1), c2) -> (fmul x, (fmul c1, c2))
5038 if (UnsafeFPMath && N1CFP && N0.getOpcode() == ISD::FMUL &&
Gabor Greifba36cb52008-08-28 21:40:38 +00005039 N0.getNode()->hasOneUse() && isa<ConstantFPSDNode>(N0.getOperand(1)))
Bill Wendlinga03e74b2009-01-30 22:57:07 +00005040 return DAG.getNode(ISD::FMUL, N->getDebugLoc(), VT, N0.getOperand(0),
Scott Michelfdc40a02009-02-17 22:15:04 +00005041 DAG.getNode(ISD::FMUL, N->getDebugLoc(), VT,
Dale Johannesende064702009-02-06 21:50:26 +00005042 N0.getOperand(1), N1));
Scott Michelfdc40a02009-02-17 22:15:04 +00005043
Dan Gohman475871a2008-07-27 21:46:04 +00005044 return SDValue();
Chris Lattner01b3d732005-09-28 22:28:18 +00005045}
5046
Dan Gohman475871a2008-07-27 21:46:04 +00005047SDValue DAGCombiner::visitFDIV(SDNode *N) {
5048 SDValue N0 = N->getOperand(0);
5049 SDValue N1 = N->getOperand(1);
Nate Begemana148d982006-01-18 22:35:16 +00005050 ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(N0);
5051 ConstantFPSDNode *N1CFP = dyn_cast<ConstantFPSDNode>(N1);
Owen Andersone50ed302009-08-10 22:56:29 +00005052 EVT VT = N->getValueType(0);
Chris Lattner01b3d732005-09-28 22:28:18 +00005053
Dan Gohman7f321562007-06-25 16:23:39 +00005054 // fold vector ops
Duncan Sands83ec4b62008-06-06 12:08:01 +00005055 if (VT.isVector()) {
Dan Gohman475871a2008-07-27 21:46:04 +00005056 SDValue FoldedVOp = SimplifyVBinOp(N);
Gabor Greifba36cb52008-08-28 21:40:38 +00005057 if (FoldedVOp.getNode()) return FoldedVOp;
Dan Gohman05d92fe2007-07-13 20:03:40 +00005058 }
Scott Michelfdc40a02009-02-17 22:15:04 +00005059
Nate Begemana148d982006-01-18 22:35:16 +00005060 // fold (fdiv c1, c2) -> c1/c2
Owen Anderson825b72b2009-08-11 20:47:22 +00005061 if (N0CFP && N1CFP && VT != MVT::ppcf128)
Bill Wendlinga03e74b2009-01-30 22:57:07 +00005062 return DAG.getNode(ISD::FDIV, N->getDebugLoc(), VT, N0, N1);
Scott Michelfdc40a02009-02-17 22:15:04 +00005063
5064
Bill Wendlinga03e74b2009-01-30 22:57:07 +00005065 // (fdiv (fneg X), (fneg Y)) -> (fdiv X, Y)
Duncan Sands25cf2272008-11-24 14:53:14 +00005066 if (char LHSNeg = isNegatibleForFree(N0, LegalOperations)) {
5067 if (char RHSNeg = isNegatibleForFree(N1, LegalOperations)) {
Chris Lattner29446522007-05-14 22:04:50 +00005068 // Both can be negated for free, check to see if at least one is cheaper
5069 // negated.
5070 if (LHSNeg == 2 || RHSNeg == 2)
Scott Michelfdc40a02009-02-17 22:15:04 +00005071 return DAG.getNode(ISD::FDIV, N->getDebugLoc(), VT,
Duncan Sands25cf2272008-11-24 14:53:14 +00005072 GetNegatedExpression(N0, DAG, LegalOperations),
5073 GetNegatedExpression(N1, DAG, LegalOperations));
Chris Lattner29446522007-05-14 22:04:50 +00005074 }
5075 }
Scott Michelfdc40a02009-02-17 22:15:04 +00005076
Dan Gohman475871a2008-07-27 21:46:04 +00005077 return SDValue();
Chris Lattner01b3d732005-09-28 22:28:18 +00005078}
5079
Dan Gohman475871a2008-07-27 21:46:04 +00005080SDValue DAGCombiner::visitFREM(SDNode *N) {
5081 SDValue N0 = N->getOperand(0);
5082 SDValue N1 = N->getOperand(1);
Nate Begemana148d982006-01-18 22:35:16 +00005083 ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(N0);
5084 ConstantFPSDNode *N1CFP = dyn_cast<ConstantFPSDNode>(N1);
Owen Andersone50ed302009-08-10 22:56:29 +00005085 EVT VT = N->getValueType(0);
Chris Lattner01b3d732005-09-28 22:28:18 +00005086
Nate Begemana148d982006-01-18 22:35:16 +00005087 // fold (frem c1, c2) -> fmod(c1,c2)
Owen Anderson825b72b2009-08-11 20:47:22 +00005088 if (N0CFP && N1CFP && VT != MVT::ppcf128)
Bill Wendlinga03e74b2009-01-30 22:57:07 +00005089 return DAG.getNode(ISD::FREM, N->getDebugLoc(), VT, N0, N1);
Dan Gohman7f321562007-06-25 16:23:39 +00005090
Dan Gohman475871a2008-07-27 21:46:04 +00005091 return SDValue();
Chris Lattner01b3d732005-09-28 22:28:18 +00005092}
5093
Dan Gohman475871a2008-07-27 21:46:04 +00005094SDValue DAGCombiner::visitFCOPYSIGN(SDNode *N) {
5095 SDValue N0 = N->getOperand(0);
5096 SDValue N1 = N->getOperand(1);
Chris Lattner12d83032006-03-05 05:30:57 +00005097 ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(N0);
5098 ConstantFPSDNode *N1CFP = dyn_cast<ConstantFPSDNode>(N1);
Owen Andersone50ed302009-08-10 22:56:29 +00005099 EVT VT = N->getValueType(0);
Chris Lattner12d83032006-03-05 05:30:57 +00005100
Owen Anderson825b72b2009-08-11 20:47:22 +00005101 if (N0CFP && N1CFP && VT != MVT::ppcf128) // Constant fold
Bill Wendlingfc4b6772009-02-01 11:19:36 +00005102 return DAG.getNode(ISD::FCOPYSIGN, N->getDebugLoc(), VT, N0, N1);
Scott Michelfdc40a02009-02-17 22:15:04 +00005103
Chris Lattner12d83032006-03-05 05:30:57 +00005104 if (N1CFP) {
Dale Johannesene6c17422007-08-26 01:18:27 +00005105 const APFloat& V = N1CFP->getValueAPF();
Chris Lattner12d83032006-03-05 05:30:57 +00005106 // copysign(x, c1) -> fabs(x) iff ispos(c1)
5107 // copysign(x, c1) -> fneg(fabs(x)) iff isneg(c1)
Dan Gohman760f86f2009-01-22 21:58:43 +00005108 if (!V.isNegative()) {
5109 if (!LegalOperations || TLI.isOperationLegal(ISD::FABS, VT))
Bill Wendling0225a1d2009-01-30 23:15:49 +00005110 return DAG.getNode(ISD::FABS, N->getDebugLoc(), VT, N0);
Dan Gohman760f86f2009-01-22 21:58:43 +00005111 } else {
5112 if (!LegalOperations || TLI.isOperationLegal(ISD::FNEG, VT))
Bill Wendling0225a1d2009-01-30 23:15:49 +00005113 return DAG.getNode(ISD::FNEG, N->getDebugLoc(), VT,
Bill Wendling9729c5a2009-01-31 03:12:48 +00005114 DAG.getNode(ISD::FABS, N0.getDebugLoc(), VT, N0));
Dan Gohman760f86f2009-01-22 21:58:43 +00005115 }
Chris Lattner12d83032006-03-05 05:30:57 +00005116 }
Scott Michelfdc40a02009-02-17 22:15:04 +00005117
Chris Lattner12d83032006-03-05 05:30:57 +00005118 // copysign(fabs(x), y) -> copysign(x, y)
5119 // copysign(fneg(x), y) -> copysign(x, y)
5120 // copysign(copysign(x,z), y) -> copysign(x, y)
5121 if (N0.getOpcode() == ISD::FABS || N0.getOpcode() == ISD::FNEG ||
5122 N0.getOpcode() == ISD::FCOPYSIGN)
Bill Wendling0225a1d2009-01-30 23:15:49 +00005123 return DAG.getNode(ISD::FCOPYSIGN, N->getDebugLoc(), VT,
5124 N0.getOperand(0), N1);
Chris Lattner12d83032006-03-05 05:30:57 +00005125
5126 // copysign(x, abs(y)) -> abs(x)
5127 if (N1.getOpcode() == ISD::FABS)
Bill Wendling0225a1d2009-01-30 23:15:49 +00005128 return DAG.getNode(ISD::FABS, N->getDebugLoc(), VT, N0);
Scott Michelfdc40a02009-02-17 22:15:04 +00005129
Chris Lattner12d83032006-03-05 05:30:57 +00005130 // copysign(x, copysign(y,z)) -> copysign(x, z)
5131 if (N1.getOpcode() == ISD::FCOPYSIGN)
Bill Wendling0225a1d2009-01-30 23:15:49 +00005132 return DAG.getNode(ISD::FCOPYSIGN, N->getDebugLoc(), VT,
5133 N0, N1.getOperand(1));
Scott Michelfdc40a02009-02-17 22:15:04 +00005134
Chris Lattner12d83032006-03-05 05:30:57 +00005135 // copysign(x, fp_extend(y)) -> copysign(x, y)
5136 // copysign(x, fp_round(y)) -> copysign(x, y)
5137 if (N1.getOpcode() == ISD::FP_EXTEND || N1.getOpcode() == ISD::FP_ROUND)
Bill Wendling0225a1d2009-01-30 23:15:49 +00005138 return DAG.getNode(ISD::FCOPYSIGN, N->getDebugLoc(), VT,
5139 N0, N1.getOperand(0));
Scott Michelfdc40a02009-02-17 22:15:04 +00005140
Dan Gohman475871a2008-07-27 21:46:04 +00005141 return SDValue();
Chris Lattner12d83032006-03-05 05:30:57 +00005142}
5143
Dan Gohman475871a2008-07-27 21:46:04 +00005144SDValue DAGCombiner::visitSINT_TO_FP(SDNode *N) {
5145 SDValue N0 = N->getOperand(0);
Nate Begeman646d7e22005-09-02 21:18:40 +00005146 ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0);
Owen Andersone50ed302009-08-10 22:56:29 +00005147 EVT VT = N->getValueType(0);
5148 EVT OpVT = N0.getValueType();
Chris Lattnercda88752008-06-26 00:16:49 +00005149
Nate Begeman1d4d4142005-09-01 00:19:25 +00005150 // fold (sint_to_fp c1) -> c1fp
Stuart Hastings7e334182011-03-02 19:36:30 +00005151 if (N0C && OpVT != MVT::ppcf128 &&
5152 // ...but only if the target supports immediate floating-point values
5153 (Level == llvm::Unrestricted || TLI.isOperationLegalOrCustom(llvm::ISD::ConstantFP, VT)))
Bill Wendling0225a1d2009-01-30 23:15:49 +00005154 return DAG.getNode(ISD::SINT_TO_FP, N->getDebugLoc(), VT, N0);
Scott Michelfdc40a02009-02-17 22:15:04 +00005155
Chris Lattnercda88752008-06-26 00:16:49 +00005156 // If the input is a legal type, and SINT_TO_FP is not legal on this target,
5157 // but UINT_TO_FP is legal on this target, try to convert.
Dan Gohmanf560ffa2009-01-28 17:46:25 +00005158 if (!TLI.isOperationLegalOrCustom(ISD::SINT_TO_FP, OpVT) &&
5159 TLI.isOperationLegalOrCustom(ISD::UINT_TO_FP, OpVT)) {
Scott Michelfdc40a02009-02-17 22:15:04 +00005160 // If the sign bit is known to be zero, we can change this to UINT_TO_FP.
Chris Lattnercda88752008-06-26 00:16:49 +00005161 if (DAG.SignBitIsZero(N0))
Bill Wendling0225a1d2009-01-30 23:15:49 +00005162 return DAG.getNode(ISD::UINT_TO_FP, N->getDebugLoc(), VT, N0);
Chris Lattnercda88752008-06-26 00:16:49 +00005163 }
Bill Wendling0225a1d2009-01-30 23:15:49 +00005164
Dan Gohman475871a2008-07-27 21:46:04 +00005165 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00005166}
5167
Dan Gohman475871a2008-07-27 21:46:04 +00005168SDValue DAGCombiner::visitUINT_TO_FP(SDNode *N) {
5169 SDValue N0 = N->getOperand(0);
Nate Begeman646d7e22005-09-02 21:18:40 +00005170 ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0);
Owen Andersone50ed302009-08-10 22:56:29 +00005171 EVT VT = N->getValueType(0);
5172 EVT OpVT = N0.getValueType();
Nate Begemana148d982006-01-18 22:35:16 +00005173
Nate Begeman1d4d4142005-09-01 00:19:25 +00005174 // fold (uint_to_fp c1) -> c1fp
Stuart Hastings7e334182011-03-02 19:36:30 +00005175 if (N0C && OpVT != MVT::ppcf128 &&
5176 // ...but only if the target supports immediate floating-point values
5177 (Level == llvm::Unrestricted || TLI.isOperationLegalOrCustom(llvm::ISD::ConstantFP, VT)))
Bill Wendling0225a1d2009-01-30 23:15:49 +00005178 return DAG.getNode(ISD::UINT_TO_FP, N->getDebugLoc(), VT, N0);
Scott Michelfdc40a02009-02-17 22:15:04 +00005179
Chris Lattnercda88752008-06-26 00:16:49 +00005180 // If the input is a legal type, and UINT_TO_FP is not legal on this target,
5181 // but SINT_TO_FP is legal on this target, try to convert.
Dan Gohmanf560ffa2009-01-28 17:46:25 +00005182 if (!TLI.isOperationLegalOrCustom(ISD::UINT_TO_FP, OpVT) &&
5183 TLI.isOperationLegalOrCustom(ISD::SINT_TO_FP, OpVT)) {
Scott Michelfdc40a02009-02-17 22:15:04 +00005184 // If the sign bit is known to be zero, we can change this to SINT_TO_FP.
Chris Lattnercda88752008-06-26 00:16:49 +00005185 if (DAG.SignBitIsZero(N0))
Bill Wendling0225a1d2009-01-30 23:15:49 +00005186 return DAG.getNode(ISD::SINT_TO_FP, N->getDebugLoc(), VT, N0);
Chris Lattnercda88752008-06-26 00:16:49 +00005187 }
Scott Michelfdc40a02009-02-17 22:15:04 +00005188
Dan Gohman475871a2008-07-27 21:46:04 +00005189 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00005190}
5191
Dan Gohman475871a2008-07-27 21:46:04 +00005192SDValue DAGCombiner::visitFP_TO_SINT(SDNode *N) {
5193 SDValue N0 = N->getOperand(0);
Nate Begemana148d982006-01-18 22:35:16 +00005194 ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(N0);
Owen Andersone50ed302009-08-10 22:56:29 +00005195 EVT VT = N->getValueType(0);
Scott Michelfdc40a02009-02-17 22:15:04 +00005196
Nate Begeman1d4d4142005-09-01 00:19:25 +00005197 // fold (fp_to_sint c1fp) -> c1
Nate Begeman646d7e22005-09-02 21:18:40 +00005198 if (N0CFP)
Bill Wendling0225a1d2009-01-30 23:15:49 +00005199 return DAG.getNode(ISD::FP_TO_SINT, N->getDebugLoc(), VT, N0);
5200
Dan Gohman475871a2008-07-27 21:46:04 +00005201 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00005202}
5203
Dan Gohman475871a2008-07-27 21:46:04 +00005204SDValue DAGCombiner::visitFP_TO_UINT(SDNode *N) {
5205 SDValue N0 = N->getOperand(0);
Nate Begemana148d982006-01-18 22:35:16 +00005206 ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(N0);
Owen Andersone50ed302009-08-10 22:56:29 +00005207 EVT VT = N->getValueType(0);
Scott Michelfdc40a02009-02-17 22:15:04 +00005208
Nate Begeman1d4d4142005-09-01 00:19:25 +00005209 // fold (fp_to_uint c1fp) -> c1
Owen Anderson825b72b2009-08-11 20:47:22 +00005210 if (N0CFP && VT != MVT::ppcf128)
Bill Wendling0225a1d2009-01-30 23:15:49 +00005211 return DAG.getNode(ISD::FP_TO_UINT, N->getDebugLoc(), VT, N0);
5212
Dan Gohman475871a2008-07-27 21:46:04 +00005213 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00005214}
5215
Dan Gohman475871a2008-07-27 21:46:04 +00005216SDValue DAGCombiner::visitFP_ROUND(SDNode *N) {
5217 SDValue N0 = N->getOperand(0);
5218 SDValue N1 = N->getOperand(1);
Nate Begemana148d982006-01-18 22:35:16 +00005219 ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(N0);
Owen Andersone50ed302009-08-10 22:56:29 +00005220 EVT VT = N->getValueType(0);
Scott Michelfdc40a02009-02-17 22:15:04 +00005221
Nate Begeman1d4d4142005-09-01 00:19:25 +00005222 // fold (fp_round c1fp) -> c1fp
Owen Anderson825b72b2009-08-11 20:47:22 +00005223 if (N0CFP && N0.getValueType() != MVT::ppcf128)
Bill Wendling0225a1d2009-01-30 23:15:49 +00005224 return DAG.getNode(ISD::FP_ROUND, N->getDebugLoc(), VT, N0, N1);
Scott Michelfdc40a02009-02-17 22:15:04 +00005225
Chris Lattner79dbea52006-03-13 06:26:26 +00005226 // fold (fp_round (fp_extend x)) -> x
5227 if (N0.getOpcode() == ISD::FP_EXTEND && VT == N0.getOperand(0).getValueType())
5228 return N0.getOperand(0);
Scott Michelfdc40a02009-02-17 22:15:04 +00005229
Chris Lattner0aa5e6f2008-01-24 06:45:35 +00005230 // fold (fp_round (fp_round x)) -> (fp_round x)
5231 if (N0.getOpcode() == ISD::FP_ROUND) {
5232 // This is a value preserving truncation if both round's are.
5233 bool IsTrunc = N->getConstantOperandVal(1) == 1 &&
Gabor Greifba36cb52008-08-28 21:40:38 +00005234 N0.getNode()->getConstantOperandVal(1) == 1;
Bill Wendling0225a1d2009-01-30 23:15:49 +00005235 return DAG.getNode(ISD::FP_ROUND, N->getDebugLoc(), VT, N0.getOperand(0),
Chris Lattner0aa5e6f2008-01-24 06:45:35 +00005236 DAG.getIntPtrConstant(IsTrunc));
5237 }
Scott Michelfdc40a02009-02-17 22:15:04 +00005238
Chris Lattner79dbea52006-03-13 06:26:26 +00005239 // fold (fp_round (copysign X, Y)) -> (copysign (fp_round X), Y)
Gabor Greifba36cb52008-08-28 21:40:38 +00005240 if (N0.getOpcode() == ISD::FCOPYSIGN && N0.getNode()->hasOneUse()) {
Bill Wendling0225a1d2009-01-30 23:15:49 +00005241 SDValue Tmp = DAG.getNode(ISD::FP_ROUND, N0.getDebugLoc(), VT,
5242 N0.getOperand(0), N1);
Gabor Greifba36cb52008-08-28 21:40:38 +00005243 AddToWorkList(Tmp.getNode());
Bill Wendling0225a1d2009-01-30 23:15:49 +00005244 return DAG.getNode(ISD::FCOPYSIGN, N->getDebugLoc(), VT,
5245 Tmp, N0.getOperand(1));
Chris Lattner79dbea52006-03-13 06:26:26 +00005246 }
Scott Michelfdc40a02009-02-17 22:15:04 +00005247
Dan Gohman475871a2008-07-27 21:46:04 +00005248 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00005249}
5250
Dan Gohman475871a2008-07-27 21:46:04 +00005251SDValue DAGCombiner::visitFP_ROUND_INREG(SDNode *N) {
5252 SDValue N0 = N->getOperand(0);
Owen Andersone50ed302009-08-10 22:56:29 +00005253 EVT VT = N->getValueType(0);
5254 EVT EVT = cast<VTSDNode>(N->getOperand(1))->getVT();
Nate Begeman646d7e22005-09-02 21:18:40 +00005255 ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(N0);
Scott Michelfdc40a02009-02-17 22:15:04 +00005256
Nate Begeman1d4d4142005-09-01 00:19:25 +00005257 // fold (fp_round_inreg c1fp) -> c1fp
Chris Lattner2392ae72010-04-15 04:48:01 +00005258 if (N0CFP && isTypeLegal(EVT)) {
Dan Gohman4fbd7962008-09-12 18:08:03 +00005259 SDValue Round = DAG.getConstantFP(*N0CFP->getConstantFPValue(), EVT);
Bill Wendling0225a1d2009-01-30 23:15:49 +00005260 return DAG.getNode(ISD::FP_EXTEND, N->getDebugLoc(), VT, Round);
Nate Begeman1d4d4142005-09-01 00:19:25 +00005261 }
Bill Wendling0225a1d2009-01-30 23:15:49 +00005262
Dan Gohman475871a2008-07-27 21:46:04 +00005263 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00005264}
5265
Dan Gohman475871a2008-07-27 21:46:04 +00005266SDValue DAGCombiner::visitFP_EXTEND(SDNode *N) {
5267 SDValue N0 = N->getOperand(0);
Nate Begemana148d982006-01-18 22:35:16 +00005268 ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(N0);
Owen Andersone50ed302009-08-10 22:56:29 +00005269 EVT VT = N->getValueType(0);
Scott Michelfdc40a02009-02-17 22:15:04 +00005270
Chris Lattner5938bef2007-12-29 06:55:23 +00005271 // If this is fp_round(fpextend), don't fold it, allow ourselves to be folded.
Scott Michelfdc40a02009-02-17 22:15:04 +00005272 if (N->hasOneUse() &&
Dan Gohmane7852d02009-01-26 04:35:06 +00005273 N->use_begin()->getOpcode() == ISD::FP_ROUND)
Dan Gohman475871a2008-07-27 21:46:04 +00005274 return SDValue();
Chris Lattner0bd48932008-01-17 07:00:52 +00005275
Nate Begeman1d4d4142005-09-01 00:19:25 +00005276 // fold (fp_extend c1fp) -> c1fp
Owen Anderson825b72b2009-08-11 20:47:22 +00005277 if (N0CFP && VT != MVT::ppcf128)
Bill Wendling0225a1d2009-01-30 23:15:49 +00005278 return DAG.getNode(ISD::FP_EXTEND, N->getDebugLoc(), VT, N0);
Chris Lattner0bd48932008-01-17 07:00:52 +00005279
5280 // Turn fp_extend(fp_round(X, 1)) -> x since the fp_round doesn't affect the
5281 // value of X.
Gabor Greif12632d22008-08-30 19:29:20 +00005282 if (N0.getOpcode() == ISD::FP_ROUND
5283 && N0.getNode()->getConstantOperandVal(1) == 1) {
Dan Gohman475871a2008-07-27 21:46:04 +00005284 SDValue In = N0.getOperand(0);
Chris Lattner0bd48932008-01-17 07:00:52 +00005285 if (In.getValueType() == VT) return In;
Duncan Sands8e4eb092008-06-08 20:54:56 +00005286 if (VT.bitsLT(In.getValueType()))
Bill Wendling0225a1d2009-01-30 23:15:49 +00005287 return DAG.getNode(ISD::FP_ROUND, N->getDebugLoc(), VT,
5288 In, N0.getOperand(1));
5289 return DAG.getNode(ISD::FP_EXTEND, N->getDebugLoc(), VT, In);
Chris Lattner0bd48932008-01-17 07:00:52 +00005290 }
Scott Michelfdc40a02009-02-17 22:15:04 +00005291
Chris Lattner0bd48932008-01-17 07:00:52 +00005292 // fold (fpext (load x)) -> (fpext (fptrunc (extload x)))
Gabor Greifba36cb52008-08-28 21:40:38 +00005293 if (ISD::isNON_EXTLoad(N0.getNode()) && N0.hasOneUse() &&
Duncan Sands25cf2272008-11-24 14:53:14 +00005294 ((!LegalOperations && !cast<LoadSDNode>(N0)->isVolatile()) ||
Evan Cheng03294662008-10-14 21:26:46 +00005295 TLI.isLoadExtLegal(ISD::EXTLOAD, N0.getValueType()))) {
Evan Cheng466685d2006-10-09 20:57:25 +00005296 LoadSDNode *LN0 = cast<LoadSDNode>(N0);
Stuart Hastingsa9011292011-02-16 16:23:55 +00005297 SDValue ExtLoad = DAG.getExtLoad(ISD::EXTLOAD, N->getDebugLoc(), VT,
Bill Wendling0225a1d2009-01-30 23:15:49 +00005298 LN0->getChain(),
Chris Lattner3d6ccfb2010-09-21 17:04:51 +00005299 LN0->getBasePtr(), LN0->getPointerInfo(),
Duncan Sands25cf2272008-11-24 14:53:14 +00005300 N0.getValueType(),
David Greene1e559442010-02-15 17:00:31 +00005301 LN0->isVolatile(), LN0->isNonTemporal(),
5302 LN0->getAlignment());
Chris Lattnere564dbb2006-05-05 21:34:35 +00005303 CombineTo(N, ExtLoad);
Bill Wendling0225a1d2009-01-30 23:15:49 +00005304 CombineTo(N0.getNode(),
5305 DAG.getNode(ISD::FP_ROUND, N0.getDebugLoc(),
5306 N0.getValueType(), ExtLoad, DAG.getIntPtrConstant(1)),
Chris Lattnere564dbb2006-05-05 21:34:35 +00005307 ExtLoad.getValue(1));
Dan Gohman475871a2008-07-27 21:46:04 +00005308 return SDValue(N, 0); // Return N so it doesn't get rechecked!
Chris Lattnere564dbb2006-05-05 21:34:35 +00005309 }
Duncan Sandsd4b9c172008-06-13 19:07:40 +00005310
Dan Gohman475871a2008-07-27 21:46:04 +00005311 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00005312}
5313
Dan Gohman475871a2008-07-27 21:46:04 +00005314SDValue DAGCombiner::visitFNEG(SDNode *N) {
5315 SDValue N0 = N->getOperand(0);
Anton Korobeynikov2bcf60a2009-10-20 21:37:45 +00005316 EVT VT = N->getValueType(0);
Nate Begemana148d982006-01-18 22:35:16 +00005317
Duncan Sands25cf2272008-11-24 14:53:14 +00005318 if (isNegatibleForFree(N0, LegalOperations))
5319 return GetNegatedExpression(N0, DAG, LegalOperations);
Dan Gohman23ff1822007-07-02 15:48:56 +00005320
Chris Lattner3bd39d42008-01-27 17:42:27 +00005321 // Transform fneg(bitconvert(x)) -> bitconvert(x^sign) to avoid loading
5322 // constant pool values.
Wesley Peckbf17cfa2010-11-23 03:31:01 +00005323 if (N0.getOpcode() == ISD::BITCAST &&
Anton Korobeynikov2bcf60a2009-10-20 21:37:45 +00005324 !VT.isVector() &&
5325 N0.getNode()->hasOneUse() &&
5326 N0.getOperand(0).getValueType().isInteger()) {
Dan Gohman475871a2008-07-27 21:46:04 +00005327 SDValue Int = N0.getOperand(0);
Owen Andersone50ed302009-08-10 22:56:29 +00005328 EVT IntVT = Int.getValueType();
Duncan Sands83ec4b62008-06-06 12:08:01 +00005329 if (IntVT.isInteger() && !IntVT.isVector()) {
Duncan Sandsb0d5cdd2009-02-01 18:06:53 +00005330 Int = DAG.getNode(ISD::XOR, N0.getDebugLoc(), IntVT, Int,
5331 DAG.getConstant(APInt::getSignBit(IntVT.getSizeInBits()), IntVT));
Gabor Greifba36cb52008-08-28 21:40:38 +00005332 AddToWorkList(Int.getNode());
Wesley Peckbf17cfa2010-11-23 03:31:01 +00005333 return DAG.getNode(ISD::BITCAST, N->getDebugLoc(),
Anton Korobeynikov2bcf60a2009-10-20 21:37:45 +00005334 VT, Int);
Chris Lattner3bd39d42008-01-27 17:42:27 +00005335 }
5336 }
Scott Michelfdc40a02009-02-17 22:15:04 +00005337
Dan Gohman475871a2008-07-27 21:46:04 +00005338 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00005339}
5340
Dan Gohman475871a2008-07-27 21:46:04 +00005341SDValue DAGCombiner::visitFABS(SDNode *N) {
5342 SDValue N0 = N->getOperand(0);
Nate Begemana148d982006-01-18 22:35:16 +00005343 ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(N0);
Owen Andersone50ed302009-08-10 22:56:29 +00005344 EVT VT = N->getValueType(0);
Scott Michelfdc40a02009-02-17 22:15:04 +00005345
Nate Begeman1d4d4142005-09-01 00:19:25 +00005346 // fold (fabs c1) -> fabs(c1)
Owen Anderson825b72b2009-08-11 20:47:22 +00005347 if (N0CFP && VT != MVT::ppcf128)
Bill Wendlingc0debad2009-01-30 23:27:35 +00005348 return DAG.getNode(ISD::FABS, N->getDebugLoc(), VT, N0);
Nate Begeman1d4d4142005-09-01 00:19:25 +00005349 // fold (fabs (fabs x)) -> (fabs x)
Chris Lattner12d83032006-03-05 05:30:57 +00005350 if (N0.getOpcode() == ISD::FABS)
Nate Begeman83e75ec2005-09-06 04:43:02 +00005351 return N->getOperand(0);
Nate Begeman1d4d4142005-09-01 00:19:25 +00005352 // fold (fabs (fneg x)) -> (fabs x)
Chris Lattner12d83032006-03-05 05:30:57 +00005353 // fold (fabs (fcopysign x, y)) -> (fabs x)
5354 if (N0.getOpcode() == ISD::FNEG || N0.getOpcode() == ISD::FCOPYSIGN)
Bill Wendlingc0debad2009-01-30 23:27:35 +00005355 return DAG.getNode(ISD::FABS, N->getDebugLoc(), VT, N0.getOperand(0));
Scott Michelfdc40a02009-02-17 22:15:04 +00005356
Chris Lattner3bd39d42008-01-27 17:42:27 +00005357 // Transform fabs(bitconvert(x)) -> bitconvert(x&~sign) to avoid loading
5358 // constant pool values.
Wesley Peckbf17cfa2010-11-23 03:31:01 +00005359 if (N0.getOpcode() == ISD::BITCAST && N0.getNode()->hasOneUse() &&
Duncan Sands83ec4b62008-06-06 12:08:01 +00005360 N0.getOperand(0).getValueType().isInteger() &&
5361 !N0.getOperand(0).getValueType().isVector()) {
Dan Gohman475871a2008-07-27 21:46:04 +00005362 SDValue Int = N0.getOperand(0);
Owen Andersone50ed302009-08-10 22:56:29 +00005363 EVT IntVT = Int.getValueType();
Duncan Sands83ec4b62008-06-06 12:08:01 +00005364 if (IntVT.isInteger() && !IntVT.isVector()) {
Scott Michelfdc40a02009-02-17 22:15:04 +00005365 Int = DAG.getNode(ISD::AND, N0.getDebugLoc(), IntVT, Int,
Duncan Sandsb0d5cdd2009-02-01 18:06:53 +00005366 DAG.getConstant(~APInt::getSignBit(IntVT.getSizeInBits()), IntVT));
Gabor Greifba36cb52008-08-28 21:40:38 +00005367 AddToWorkList(Int.getNode());
Wesley Peckbf17cfa2010-11-23 03:31:01 +00005368 return DAG.getNode(ISD::BITCAST, N->getDebugLoc(),
Bill Wendlingc0debad2009-01-30 23:27:35 +00005369 N->getValueType(0), Int);
Chris Lattner3bd39d42008-01-27 17:42:27 +00005370 }
5371 }
Scott Michelfdc40a02009-02-17 22:15:04 +00005372
Dan Gohman475871a2008-07-27 21:46:04 +00005373 return SDValue();
Nate Begeman1d4d4142005-09-01 00:19:25 +00005374}
5375
Dan Gohman475871a2008-07-27 21:46:04 +00005376SDValue DAGCombiner::visitBRCOND(SDNode *N) {
5377 SDValue Chain = N->getOperand(0);
5378 SDValue N1 = N->getOperand(1);
5379 SDValue N2 = N->getOperand(2);
Scott Michelfdc40a02009-02-17 22:15:04 +00005380
Dan Gohmane0f06c72009-11-17 00:47:23 +00005381 // If N is a constant we could fold this into a fallthrough or unconditional
5382 // branch. However that doesn't happen very often in normal code, because
5383 // Instcombine/SimplifyCFG should have handled the available opportunities.
5384 // If we did this folding here, it would be necessary to update the
5385 // MachineBasicBlock CFG, which is awkward.
5386
Nate Begeman750ac1b2006-02-01 07:19:44 +00005387 // fold a brcond with a setcc condition into a BR_CC node if BR_CC is legal
5388 // on the target.
Scott Michelfdc40a02009-02-17 22:15:04 +00005389 if (N1.getOpcode() == ISD::SETCC &&
Owen Anderson825b72b2009-08-11 20:47:22 +00005390 TLI.isOperationLegalOrCustom(ISD::BR_CC, MVT::Other)) {
5391 return DAG.getNode(ISD::BR_CC, N->getDebugLoc(), MVT::Other,
Bill Wendlingc0debad2009-01-30 23:27:35 +00005392 Chain, N1.getOperand(2),
Nate Begeman750ac1b2006-02-01 07:19:44 +00005393 N1.getOperand(0), N1.getOperand(1), N2);
5394 }
Bill Wendlingc0debad2009-01-30 23:27:35 +00005395
Evan Cheng2a135ae2010-10-04 22:41:01 +00005396 if ((N1.hasOneUse() && N1.getOpcode() == ISD::SRL) ||
5397 ((N1.getOpcode() == ISD::TRUNCATE && N1.hasOneUse()) &&
5398 (N1.getOperand(0).hasOneUse() &&
5399 N1.getOperand(0).getOpcode() == ISD::SRL))) {
5400 SDNode *Trunc = 0;
5401 if (N1.getOpcode() == ISD::TRUNCATE) {
5402 // Look pass the truncate.
5403 Trunc = N1.getNode();
5404 N1 = N1.getOperand(0);
5405 }
Evan Chengd40d03e2010-01-06 19:38:29 +00005406
Bill Wendlinga02a3dd2009-03-26 06:14:09 +00005407 // Match this pattern so that we can generate simpler code:
5408 //
5409 // %a = ...
5410 // %b = and i32 %a, 2
5411 // %c = srl i32 %b, 1
5412 // brcond i32 %c ...
5413 //
5414 // into
Wesley Peckbf17cfa2010-11-23 03:31:01 +00005415 //
Bill Wendlinga02a3dd2009-03-26 06:14:09 +00005416 // %a = ...
Evan Chengd40d03e2010-01-06 19:38:29 +00005417 // %b = and i32 %a, 2
Bill Wendlinga02a3dd2009-03-26 06:14:09 +00005418 // %c = setcc eq %b, 0
5419 // brcond %c ...
5420 //
5421 // This applies only when the AND constant value has one bit set and the
5422 // SRL constant is equal to the log2 of the AND constant. The back-end is
5423 // smart enough to convert the result into a TEST/JMP sequence.
5424 SDValue Op0 = N1.getOperand(0);
5425 SDValue Op1 = N1.getOperand(1);
5426
5427 if (Op0.getOpcode() == ISD::AND &&
Bill Wendlinga02a3dd2009-03-26 06:14:09 +00005428 Op1.getOpcode() == ISD::Constant) {
Bill Wendlinga02a3dd2009-03-26 06:14:09 +00005429 SDValue AndOp1 = Op0.getOperand(1);
5430
5431 if (AndOp1.getOpcode() == ISD::Constant) {
5432 const APInt &AndConst = cast<ConstantSDNode>(AndOp1)->getAPIntValue();
5433
5434 if (AndConst.isPowerOf2() &&
5435 cast<ConstantSDNode>(Op1)->getAPIntValue()==AndConst.logBase2()) {
5436 SDValue SetCC =
5437 DAG.getSetCC(N->getDebugLoc(),
5438 TLI.getSetCCResultType(Op0.getValueType()),
5439 Op0, DAG.getConstant(0, Op0.getValueType()),
5440 ISD::SETNE);
5441
Evan Chengd40d03e2010-01-06 19:38:29 +00005442 SDValue NewBRCond = DAG.getNode(ISD::BRCOND, N->getDebugLoc(),
5443 MVT::Other, Chain, SetCC, N2);
5444 // Don't add the new BRCond into the worklist or else SimplifySelectCC
5445 // will convert it back to (X & C1) >> C2.
5446 CombineTo(N, NewBRCond, false);
5447 // Truncate is dead.
5448 if (Trunc) {
5449 removeFromWorkList(Trunc);
5450 DAG.DeleteNode(Trunc);
5451 }
Bill Wendlinga02a3dd2009-03-26 06:14:09 +00005452 // Replace the uses of SRL with SETCC
Evan Cheng2c755ba2010-02-27 07:36:59 +00005453 WorkListRemover DeadNodes(*this);
5454 DAG.ReplaceAllUsesOfValueWith(N1, SetCC, &DeadNodes);
Bill Wendlinga02a3dd2009-03-26 06:14:09 +00005455 removeFromWorkList(N1.getNode());
5456 DAG.DeleteNode(N1.getNode());
Evan Chengd40d03e2010-01-06 19:38:29 +00005457 return SDValue(N, 0); // Return N so it doesn't get rechecked!
Bill Wendlinga02a3dd2009-03-26 06:14:09 +00005458 }
5459 }
5460 }
Evan Cheng2a135ae2010-10-04 22:41:01 +00005461
5462 if (Trunc)
5463 // Restore N1 if the above transformation doesn't match.
5464 N1 = N->getOperand(1);
Bill Wendlinga02a3dd2009-03-26 06:14:09 +00005465 }
Wesley Peckbf17cfa2010-11-23 03:31:01 +00005466
Evan Cheng2c755ba2010-02-27 07:36:59 +00005467 // Transform br(xor(x, y)) -> br(x != y)
5468 // Transform br(xor(xor(x,y), 1)) -> br (x == y)
5469 if (N1.hasOneUse() && N1.getOpcode() == ISD::XOR) {
5470 SDNode *TheXor = N1.getNode();
5471 SDValue Op0 = TheXor->getOperand(0);
5472 SDValue Op1 = TheXor->getOperand(1);
5473 if (Op0.getOpcode() == Op1.getOpcode()) {
5474 // Avoid missing important xor optimizations.
5475 SDValue Tmp = visitXOR(TheXor);
Bill Wendling86c5abb2010-04-20 01:25:01 +00005476 if (Tmp.getNode() && Tmp.getNode() != TheXor) {
Evan Cheng2c755ba2010-02-27 07:36:59 +00005477 DEBUG(dbgs() << "\nReplacing.8 ";
5478 TheXor->dump(&DAG);
5479 dbgs() << "\nWith: ";
5480 Tmp.getNode()->dump(&DAG);
5481 dbgs() << '\n');
5482 WorkListRemover DeadNodes(*this);
5483 DAG.ReplaceAllUsesOfValueWith(N1, Tmp, &DeadNodes);
5484 removeFromWorkList(TheXor);
5485 DAG.DeleteNode(TheXor);
5486 return DAG.getNode(ISD::BRCOND, N->getDebugLoc(),
5487 MVT::Other, Chain, Tmp, N2);
5488 }
5489 }
5490
5491 if (Op0.getOpcode() != ISD::SETCC && Op1.getOpcode() != ISD::SETCC) {
5492 bool Equal = false;
5493 if (ConstantSDNode *RHSCI = dyn_cast<ConstantSDNode>(Op0))
5494 if (RHSCI->getAPIntValue() == 1 && Op0.hasOneUse() &&
5495 Op0.getOpcode() == ISD::XOR) {
5496 TheXor = Op0.getNode();
5497 Equal = true;
5498 }
5499
Evan Cheng2a135ae2010-10-04 22:41:01 +00005500 EVT SetCCVT = N1.getValueType();
Evan Cheng2c755ba2010-02-27 07:36:59 +00005501 if (LegalTypes)
5502 SetCCVT = TLI.getSetCCResultType(SetCCVT);
5503 SDValue SetCC = DAG.getSetCC(TheXor->getDebugLoc(),
5504 SetCCVT,
5505 Op0, Op1,
5506 Equal ? ISD::SETEQ : ISD::SETNE);
5507 // Replace the uses of XOR with SETCC
5508 WorkListRemover DeadNodes(*this);
Evan Cheng2a135ae2010-10-04 22:41:01 +00005509 DAG.ReplaceAllUsesOfValueWith(N1, SetCC, &DeadNodes);
5510 removeFromWorkList(N1.getNode());
5511 DAG.DeleteNode(N1.getNode());
Evan Cheng2c755ba2010-02-27 07:36:59 +00005512 return DAG.getNode(ISD::BRCOND, N->getDebugLoc(),
5513 MVT::Other, Chain, SetCC, N2);
5514 }
5515 }
Bill Wendlinga02a3dd2009-03-26 06:14:09 +00005516
Dan Gohman475871a2008-07-27 21:46:04 +00005517 return SDValue();
Nate Begeman44728a72005-09-19 22:34:01 +00005518}
5519
Chris Lattner3ea0b472005-10-05 06:47:48 +00005520// Operand List for BR_CC: Chain, CondCC, CondLHS, CondRHS, DestBB.
5521//
Dan Gohman475871a2008-07-27 21:46:04 +00005522SDValue DAGCombiner::visitBR_CC(SDNode *N) {
Chris Lattner3ea0b472005-10-05 06:47:48 +00005523 CondCodeSDNode *CC = cast<CondCodeSDNode>(N->getOperand(1));
Dan Gohman475871a2008-07-27 21:46:04 +00005524 SDValue CondLHS = N->getOperand(2), CondRHS = N->getOperand(3);
Scott Michelfdc40a02009-02-17 22:15:04 +00005525
Dan Gohmane0f06c72009-11-17 00:47:23 +00005526 // If N is a constant we could fold this into a fallthrough or unconditional
5527 // branch. However that doesn't happen very often in normal code, because
5528 // Instcombine/SimplifyCFG should have handled the available opportunities.
5529 // If we did this folding here, it would be necessary to update the
5530 // MachineBasicBlock CFG, which is awkward.
5531
Duncan Sands8eab8a22008-06-09 11:32:28 +00005532 // Use SimplifySetCC to simplify SETCC's.
Duncan Sands5480c042009-01-01 15:52:00 +00005533 SDValue Simp = SimplifySetCC(TLI.getSetCCResultType(CondLHS.getValueType()),
Dale Johannesenff97d4f2009-02-03 00:47:48 +00005534 CondLHS, CondRHS, CC->get(), N->getDebugLoc(),
5535 false);
Gabor Greifba36cb52008-08-28 21:40:38 +00005536 if (Simp.getNode()) AddToWorkList(Simp.getNode());
Chris Lattner30f73e72006-10-14 03:52:46 +00005537
Nate Begemane17daeb2005-10-05 21:43:42 +00005538 // fold to a simpler setcc
Gabor Greifba36cb52008-08-28 21:40:38 +00005539 if (Simp.getNode() && Simp.getOpcode() == ISD::SETCC)
Owen Anderson825b72b2009-08-11 20:47:22 +00005540 return DAG.getNode(ISD::BR_CC, N->getDebugLoc(), MVT::Other,
Bill Wendlingc0debad2009-01-30 23:27:35 +00005541 N->getOperand(0), Simp.getOperand(2),
5542 Simp.getOperand(0), Simp.getOperand(1),
5543 N->getOperand(4));
5544
Dan Gohman475871a2008-07-27 21:46:04 +00005545 return SDValue();
Nate Begeman44728a72005-09-19 22:34:01 +00005546}
5547
Duncan Sandsec87aa82008-06-15 20:12:31 +00005548/// CombineToPreIndexedLoadStore - Try turning a load / store into a
5549/// pre-indexed load / store when the base pointer is an add or subtract
Chris Lattner448f2192006-11-11 00:39:41 +00005550/// and it has other uses besides the load / store. After the
5551/// transformation, the new indexed load / store has effectively folded
5552/// the add / subtract in and all of its other uses are redirected to the
5553/// new load / store.
5554bool DAGCombiner::CombineToPreIndexedLoadStore(SDNode *N) {
Duncan Sands25cf2272008-11-24 14:53:14 +00005555 if (!LegalOperations)
Chris Lattner448f2192006-11-11 00:39:41 +00005556 return false;
5557
5558 bool isLoad = true;
Dan Gohman475871a2008-07-27 21:46:04 +00005559 SDValue Ptr;
Owen Andersone50ed302009-08-10 22:56:29 +00005560 EVT VT;
Chris Lattner448f2192006-11-11 00:39:41 +00005561 if (LoadSDNode *LD = dyn_cast<LoadSDNode>(N)) {
Chris Lattnerddf89562008-01-17 19:59:44 +00005562 if (LD->isIndexed())
Evan Chenge90460e2006-12-16 06:25:23 +00005563 return false;
Dan Gohmanb625f2f2008-01-30 00:15:11 +00005564 VT = LD->getMemoryVT();
Evan Cheng83060c52007-03-07 08:07:03 +00005565 if (!TLI.isIndexedLoadLegal(ISD::PRE_INC, VT) &&
Chris Lattner448f2192006-11-11 00:39:41 +00005566 !TLI.isIndexedLoadLegal(ISD::PRE_DEC, VT))
5567 return false;
5568 Ptr = LD->getBasePtr();
5569 } else if (StoreSDNode *ST = dyn_cast<StoreSDNode>(N)) {
Chris Lattnerddf89562008-01-17 19:59:44 +00005570 if (ST->isIndexed())
Evan Chenge90460e2006-12-16 06:25:23 +00005571 return false;
Dan Gohmanb625f2f2008-01-30 00:15:11 +00005572 VT = ST->getMemoryVT();
Chris Lattner448f2192006-11-11 00:39:41 +00005573 if (!TLI.isIndexedStoreLegal(ISD::PRE_INC, VT) &&
5574 !TLI.isIndexedStoreLegal(ISD::PRE_DEC, VT))
5575 return false;
5576 Ptr = ST->getBasePtr();
5577 isLoad = false;
Bill Wendlingc0debad2009-01-30 23:27:35 +00005578 } else {
Chris Lattner448f2192006-11-11 00:39:41 +00005579 return false;
Bill Wendlingc0debad2009-01-30 23:27:35 +00005580 }
Chris Lattner448f2192006-11-11 00:39:41 +00005581
Chris Lattner9f1794e2006-11-11 00:56:29 +00005582 // If the pointer is not an add/sub, or if it doesn't have multiple uses, bail
5583 // out. There is no reason to make this a preinc/predec.
5584 if ((Ptr.getOpcode() != ISD::ADD && Ptr.getOpcode() != ISD::SUB) ||
Gabor Greifba36cb52008-08-28 21:40:38 +00005585 Ptr.getNode()->hasOneUse())
Chris Lattner9f1794e2006-11-11 00:56:29 +00005586 return false;
Chris Lattner448f2192006-11-11 00:39:41 +00005587
Chris Lattner9f1794e2006-11-11 00:56:29 +00005588 // Ask the target to do addressing mode selection.
Dan Gohman475871a2008-07-27 21:46:04 +00005589 SDValue BasePtr;
5590 SDValue Offset;
Chris Lattner9f1794e2006-11-11 00:56:29 +00005591 ISD::MemIndexedMode AM = ISD::UNINDEXED;
5592 if (!TLI.getPreIndexedAddressParts(N, BasePtr, Offset, AM, DAG))
5593 return false;
Evan Chenga7d4a042007-05-03 23:52:19 +00005594 // Don't create a indexed load / store with zero offset.
5595 if (isa<ConstantSDNode>(Offset) &&
Dan Gohman002e5d02008-03-13 22:13:53 +00005596 cast<ConstantSDNode>(Offset)->isNullValue())
Evan Chenga7d4a042007-05-03 23:52:19 +00005597 return false;
Scott Michelfdc40a02009-02-17 22:15:04 +00005598
Chris Lattner41e53fd2006-11-11 01:00:15 +00005599 // Try turning it into a pre-indexed load / store except when:
Evan Chengc843abe2007-05-24 02:35:39 +00005600 // 1) The new base ptr is a frame index.
5601 // 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 +00005602 // predecessor of the value being stored.
Evan Chengc843abe2007-05-24 02:35:39 +00005603 // 3) Another use of old base ptr is a predecessor of N. If ptr is folded
Chris Lattner9f1794e2006-11-11 00:56:29 +00005604 // that would create a cycle.
Evan Chengc843abe2007-05-24 02:35:39 +00005605 // 4) All uses are load / store ops that use it as old base ptr.
Chris Lattner448f2192006-11-11 00:39:41 +00005606
Chris Lattner41e53fd2006-11-11 01:00:15 +00005607 // Check #1. Preinc'ing a frame index would require copying the stack pointer
5608 // (plus the implicit offset) to a register to preinc anyway.
Evan Chengcaab1292009-05-06 18:25:01 +00005609 if (isa<FrameIndexSDNode>(BasePtr) || isa<RegisterSDNode>(BasePtr))
Chris Lattner41e53fd2006-11-11 01:00:15 +00005610 return false;
Scott Michelfdc40a02009-02-17 22:15:04 +00005611
Chris Lattner41e53fd2006-11-11 01:00:15 +00005612 // Check #2.
Chris Lattner9f1794e2006-11-11 00:56:29 +00005613 if (!isLoad) {
Dan Gohman475871a2008-07-27 21:46:04 +00005614 SDValue Val = cast<StoreSDNode>(N)->getValue();
Gabor Greifba36cb52008-08-28 21:40:38 +00005615 if (Val == BasePtr || BasePtr.getNode()->isPredecessorOf(Val.getNode()))
Chris Lattner9f1794e2006-11-11 00:56:29 +00005616 return false;
Chris Lattner448f2192006-11-11 00:39:41 +00005617 }
Chris Lattner9f1794e2006-11-11 00:56:29 +00005618
Evan Chengc843abe2007-05-24 02:35:39 +00005619 // Now check for #3 and #4.
Chris Lattner9f1794e2006-11-11 00:56:29 +00005620 bool RealUse = false;
Gabor Greifba36cb52008-08-28 21:40:38 +00005621 for (SDNode::use_iterator I = Ptr.getNode()->use_begin(),
5622 E = Ptr.getNode()->use_end(); I != E; ++I) {
Dan Gohman89684502008-07-27 20:43:25 +00005623 SDNode *Use = *I;
Chris Lattner9f1794e2006-11-11 00:56:29 +00005624 if (Use == N)
5625 continue;
Evan Cheng917be682008-03-04 00:41:45 +00005626 if (Use->isPredecessorOf(N))
Chris Lattner9f1794e2006-11-11 00:56:29 +00005627 return false;
5628
5629 if (!((Use->getOpcode() == ISD::LOAD &&
5630 cast<LoadSDNode>(Use)->getBasePtr() == Ptr) ||
Anton Korobeynikov4c71dfe2008-02-20 11:10:28 +00005631 (Use->getOpcode() == ISD::STORE &&
5632 cast<StoreSDNode>(Use)->getBasePtr() == Ptr)))
Chris Lattner9f1794e2006-11-11 00:56:29 +00005633 RealUse = true;
5634 }
Bill Wendlingc0debad2009-01-30 23:27:35 +00005635
Chris Lattner9f1794e2006-11-11 00:56:29 +00005636 if (!RealUse)
5637 return false;
5638
Dan Gohman475871a2008-07-27 21:46:04 +00005639 SDValue Result;
Chris Lattner9f1794e2006-11-11 00:56:29 +00005640 if (isLoad)
Bill Wendlingc0debad2009-01-30 23:27:35 +00005641 Result = DAG.getIndexedLoad(SDValue(N,0), N->getDebugLoc(),
5642 BasePtr, Offset, AM);
Chris Lattner9f1794e2006-11-11 00:56:29 +00005643 else
Bill Wendlingc0debad2009-01-30 23:27:35 +00005644 Result = DAG.getIndexedStore(SDValue(N,0), N->getDebugLoc(),
5645 BasePtr, Offset, AM);
Chris Lattner9f1794e2006-11-11 00:56:29 +00005646 ++PreIndexedNodes;
5647 ++NodesCombined;
David Greenef1090292010-01-05 01:25:00 +00005648 DEBUG(dbgs() << "\nReplacing.4 ";
Chris Lattnerbbbfa992009-08-23 06:35:02 +00005649 N->dump(&DAG);
David Greenef1090292010-01-05 01:25:00 +00005650 dbgs() << "\nWith: ";
Chris Lattnerbbbfa992009-08-23 06:35:02 +00005651 Result.getNode()->dump(&DAG);
David Greenef1090292010-01-05 01:25:00 +00005652 dbgs() << '\n');
Chris Lattnerf8dc0612008-02-03 06:49:24 +00005653 WorkListRemover DeadNodes(*this);
Chris Lattner9f1794e2006-11-11 00:56:29 +00005654 if (isLoad) {
Dan Gohman475871a2008-07-27 21:46:04 +00005655 DAG.ReplaceAllUsesOfValueWith(SDValue(N, 0), Result.getValue(0),
Chris Lattnerf8dc0612008-02-03 06:49:24 +00005656 &DeadNodes);
Dan Gohman475871a2008-07-27 21:46:04 +00005657 DAG.ReplaceAllUsesOfValueWith(SDValue(N, 1), Result.getValue(2),
Chris Lattnerf8dc0612008-02-03 06:49:24 +00005658 &DeadNodes);
Chris Lattner9f1794e2006-11-11 00:56:29 +00005659 } else {
Dan Gohman475871a2008-07-27 21:46:04 +00005660 DAG.ReplaceAllUsesOfValueWith(SDValue(N, 0), Result.getValue(1),
Chris Lattnerf8dc0612008-02-03 06:49:24 +00005661 &DeadNodes);
Chris Lattner9f1794e2006-11-11 00:56:29 +00005662 }
5663
Chris Lattner9f1794e2006-11-11 00:56:29 +00005664 // Finally, since the node is now dead, remove it from the graph.
5665 DAG.DeleteNode(N);
5666
5667 // Replace the uses of Ptr with uses of the updated base value.
5668 DAG.ReplaceAllUsesOfValueWith(Ptr, Result.getValue(isLoad ? 1 : 0),
Chris Lattnerf8dc0612008-02-03 06:49:24 +00005669 &DeadNodes);
Gabor Greifba36cb52008-08-28 21:40:38 +00005670 removeFromWorkList(Ptr.getNode());
5671 DAG.DeleteNode(Ptr.getNode());
Chris Lattner9f1794e2006-11-11 00:56:29 +00005672
5673 return true;
Chris Lattner448f2192006-11-11 00:39:41 +00005674}
5675
Duncan Sandsec87aa82008-06-15 20:12:31 +00005676/// CombineToPostIndexedLoadStore - Try to combine a load / store with a
Chris Lattner448f2192006-11-11 00:39:41 +00005677/// add / sub of the base pointer node into a post-indexed load / store.
5678/// The transformation folded the add / subtract into the new indexed
5679/// load / store effectively and all of its uses are redirected to the
5680/// new load / store.
5681bool DAGCombiner::CombineToPostIndexedLoadStore(SDNode *N) {
Duncan Sands25cf2272008-11-24 14:53:14 +00005682 if (!LegalOperations)
Chris Lattner448f2192006-11-11 00:39:41 +00005683 return false;
5684
5685 bool isLoad = true;
Dan Gohman475871a2008-07-27 21:46:04 +00005686 SDValue Ptr;
Owen Andersone50ed302009-08-10 22:56:29 +00005687 EVT VT;
Chris Lattner448f2192006-11-11 00:39:41 +00005688 if (LoadSDNode *LD = dyn_cast<LoadSDNode>(N)) {
Chris Lattnerddf89562008-01-17 19:59:44 +00005689 if (LD->isIndexed())
Evan Chenge90460e2006-12-16 06:25:23 +00005690 return false;
Dan Gohmanb625f2f2008-01-30 00:15:11 +00005691 VT = LD->getMemoryVT();
Chris Lattner448f2192006-11-11 00:39:41 +00005692 if (!TLI.isIndexedLoadLegal(ISD::POST_INC, VT) &&
5693 !TLI.isIndexedLoadLegal(ISD::POST_DEC, VT))
5694 return false;
5695 Ptr = LD->getBasePtr();
5696 } else if (StoreSDNode *ST = dyn_cast<StoreSDNode>(N)) {
Chris Lattnerddf89562008-01-17 19:59:44 +00005697 if (ST->isIndexed())
Evan Chenge90460e2006-12-16 06:25:23 +00005698 return false;
Dan Gohmanb625f2f2008-01-30 00:15:11 +00005699 VT = ST->getMemoryVT();
Chris Lattner448f2192006-11-11 00:39:41 +00005700 if (!TLI.isIndexedStoreLegal(ISD::POST_INC, VT) &&
5701 !TLI.isIndexedStoreLegal(ISD::POST_DEC, VT))
5702 return false;
5703 Ptr = ST->getBasePtr();
5704 isLoad = false;
Bill Wendlingc0debad2009-01-30 23:27:35 +00005705 } else {
Chris Lattner448f2192006-11-11 00:39:41 +00005706 return false;
Bill Wendlingc0debad2009-01-30 23:27:35 +00005707 }
Chris Lattner448f2192006-11-11 00:39:41 +00005708
Gabor Greifba36cb52008-08-28 21:40:38 +00005709 if (Ptr.getNode()->hasOneUse())
Chris Lattner9f1794e2006-11-11 00:56:29 +00005710 return false;
Scott Michelfdc40a02009-02-17 22:15:04 +00005711
Gabor Greifba36cb52008-08-28 21:40:38 +00005712 for (SDNode::use_iterator I = Ptr.getNode()->use_begin(),
5713 E = Ptr.getNode()->use_end(); I != E; ++I) {
Dan Gohman89684502008-07-27 20:43:25 +00005714 SDNode *Op = *I;
Chris Lattner9f1794e2006-11-11 00:56:29 +00005715 if (Op == N ||
5716 (Op->getOpcode() != ISD::ADD && Op->getOpcode() != ISD::SUB))
5717 continue;
5718
Dan Gohman475871a2008-07-27 21:46:04 +00005719 SDValue BasePtr;
5720 SDValue Offset;
Chris Lattner9f1794e2006-11-11 00:56:29 +00005721 ISD::MemIndexedMode AM = ISD::UNINDEXED;
5722 if (TLI.getPostIndexedAddressParts(N, Op, BasePtr, Offset, AM, DAG)) {
Evan Chenga7d4a042007-05-03 23:52:19 +00005723 // Don't create a indexed load / store with zero offset.
5724 if (isa<ConstantSDNode>(Offset) &&
Dan Gohman002e5d02008-03-13 22:13:53 +00005725 cast<ConstantSDNode>(Offset)->isNullValue())
Evan Chenga7d4a042007-05-03 23:52:19 +00005726 continue;
Chris Lattner448f2192006-11-11 00:39:41 +00005727
Chris Lattner9f1794e2006-11-11 00:56:29 +00005728 // Try turning it into a post-indexed load / store except when
5729 // 1) All uses are load / store ops that use it as base ptr.
5730 // 2) Op must be independent of N, i.e. Op is neither a predecessor
5731 // nor a successor of N. Otherwise, if Op is folded that would
5732 // create a cycle.
5733
Evan Chengcaab1292009-05-06 18:25:01 +00005734 if (isa<FrameIndexSDNode>(BasePtr) || isa<RegisterSDNode>(BasePtr))
5735 continue;
5736
Chris Lattner9f1794e2006-11-11 00:56:29 +00005737 // Check for #1.
5738 bool TryNext = false;
Gabor Greifba36cb52008-08-28 21:40:38 +00005739 for (SDNode::use_iterator II = BasePtr.getNode()->use_begin(),
5740 EE = BasePtr.getNode()->use_end(); II != EE; ++II) {
Dan Gohman89684502008-07-27 20:43:25 +00005741 SDNode *Use = *II;
Gabor Greifba36cb52008-08-28 21:40:38 +00005742 if (Use == Ptr.getNode())
Chris Lattner448f2192006-11-11 00:39:41 +00005743 continue;
5744
Chris Lattner9f1794e2006-11-11 00:56:29 +00005745 // If all the uses are load / store addresses, then don't do the
5746 // transformation.
5747 if (Use->getOpcode() == ISD::ADD || Use->getOpcode() == ISD::SUB){
5748 bool RealUse = false;
5749 for (SDNode::use_iterator III = Use->use_begin(),
5750 EEE = Use->use_end(); III != EEE; ++III) {
Dan Gohman89684502008-07-27 20:43:25 +00005751 SDNode *UseUse = *III;
Chris Lattner9f1794e2006-11-11 00:56:29 +00005752 if (!((UseUse->getOpcode() == ISD::LOAD &&
Gabor Greifba36cb52008-08-28 21:40:38 +00005753 cast<LoadSDNode>(UseUse)->getBasePtr().getNode() == Use) ||
Anton Korobeynikov4c71dfe2008-02-20 11:10:28 +00005754 (UseUse->getOpcode() == ISD::STORE &&
Gabor Greifba36cb52008-08-28 21:40:38 +00005755 cast<StoreSDNode>(UseUse)->getBasePtr().getNode() == Use)))
Chris Lattner9f1794e2006-11-11 00:56:29 +00005756 RealUse = true;
5757 }
Chris Lattner448f2192006-11-11 00:39:41 +00005758
Chris Lattner9f1794e2006-11-11 00:56:29 +00005759 if (!RealUse) {
5760 TryNext = true;
5761 break;
Chris Lattner448f2192006-11-11 00:39:41 +00005762 }
5763 }
Chris Lattner9f1794e2006-11-11 00:56:29 +00005764 }
Bill Wendlingc0debad2009-01-30 23:27:35 +00005765
Chris Lattner9f1794e2006-11-11 00:56:29 +00005766 if (TryNext)
5767 continue;
Chris Lattner448f2192006-11-11 00:39:41 +00005768
Chris Lattner9f1794e2006-11-11 00:56:29 +00005769 // Check for #2
Evan Cheng917be682008-03-04 00:41:45 +00005770 if (!Op->isPredecessorOf(N) && !N->isPredecessorOf(Op)) {
Dan Gohman475871a2008-07-27 21:46:04 +00005771 SDValue Result = isLoad
Bill Wendlingc0debad2009-01-30 23:27:35 +00005772 ? DAG.getIndexedLoad(SDValue(N,0), N->getDebugLoc(),
5773 BasePtr, Offset, AM)
5774 : DAG.getIndexedStore(SDValue(N,0), N->getDebugLoc(),
5775 BasePtr, Offset, AM);
Chris Lattner9f1794e2006-11-11 00:56:29 +00005776 ++PostIndexedNodes;
5777 ++NodesCombined;
David Greenef1090292010-01-05 01:25:00 +00005778 DEBUG(dbgs() << "\nReplacing.5 ";
Chris Lattnerbbbfa992009-08-23 06:35:02 +00005779 N->dump(&DAG);
David Greenef1090292010-01-05 01:25:00 +00005780 dbgs() << "\nWith: ";
Chris Lattnerbbbfa992009-08-23 06:35:02 +00005781 Result.getNode()->dump(&DAG);
David Greenef1090292010-01-05 01:25:00 +00005782 dbgs() << '\n');
Chris Lattnerf8dc0612008-02-03 06:49:24 +00005783 WorkListRemover DeadNodes(*this);
Chris Lattner9f1794e2006-11-11 00:56:29 +00005784 if (isLoad) {
Dan Gohman475871a2008-07-27 21:46:04 +00005785 DAG.ReplaceAllUsesOfValueWith(SDValue(N, 0), Result.getValue(0),
Chris Lattnerf8dc0612008-02-03 06:49:24 +00005786 &DeadNodes);
Dan Gohman475871a2008-07-27 21:46:04 +00005787 DAG.ReplaceAllUsesOfValueWith(SDValue(N, 1), Result.getValue(2),
Chris Lattnerf8dc0612008-02-03 06:49:24 +00005788 &DeadNodes);
Chris Lattner9f1794e2006-11-11 00:56:29 +00005789 } else {
Dan Gohman475871a2008-07-27 21:46:04 +00005790 DAG.ReplaceAllUsesOfValueWith(SDValue(N, 0), Result.getValue(1),
Chris Lattnerf8dc0612008-02-03 06:49:24 +00005791 &DeadNodes);
Chris Lattner448f2192006-11-11 00:39:41 +00005792 }
Chris Lattner9f1794e2006-11-11 00:56:29 +00005793
Chris Lattner9f1794e2006-11-11 00:56:29 +00005794 // Finally, since the node is now dead, remove it from the graph.
5795 DAG.DeleteNode(N);
5796
5797 // Replace the uses of Use with uses of the updated base value.
Dan Gohman475871a2008-07-27 21:46:04 +00005798 DAG.ReplaceAllUsesOfValueWith(SDValue(Op, 0),
Chris Lattner9f1794e2006-11-11 00:56:29 +00005799 Result.getValue(isLoad ? 1 : 0),
Chris Lattnerf8dc0612008-02-03 06:49:24 +00005800 &DeadNodes);
Chris Lattner9f1794e2006-11-11 00:56:29 +00005801 removeFromWorkList(Op);
Chris Lattner9f1794e2006-11-11 00:56:29 +00005802 DAG.DeleteNode(Op);
Chris Lattner9f1794e2006-11-11 00:56:29 +00005803 return true;
Chris Lattner448f2192006-11-11 00:39:41 +00005804 }
5805 }
5806 }
Bill Wendlingc0debad2009-01-30 23:27:35 +00005807
Chris Lattner448f2192006-11-11 00:39:41 +00005808 return false;
5809}
5810
Dan Gohman475871a2008-07-27 21:46:04 +00005811SDValue DAGCombiner::visitLOAD(SDNode *N) {
Evan Cheng466685d2006-10-09 20:57:25 +00005812 LoadSDNode *LD = cast<LoadSDNode>(N);
Dan Gohman475871a2008-07-27 21:46:04 +00005813 SDValue Chain = LD->getChain();
5814 SDValue Ptr = LD->getBasePtr();
Scott Michelfdc40a02009-02-17 22:15:04 +00005815
Evan Cheng45a7ca92007-05-01 00:38:21 +00005816 // If load is not volatile and there are no uses of the loaded value (and
5817 // the updated indexed value in case of indexed loads), change uses of the
5818 // chain value into uses of the chain input (i.e. delete the dead load).
5819 if (!LD->isVolatile()) {
Owen Anderson825b72b2009-08-11 20:47:22 +00005820 if (N->getValueType(1) == MVT::Other) {
Evan Cheng498f5592007-05-01 08:53:39 +00005821 // Unindexed loads.
Evan Cheng02c42852008-01-16 23:11:54 +00005822 if (N->hasNUsesOfValue(0, 0)) {
5823 // It's not safe to use the two value CombineTo variant here. e.g.
5824 // v1, chain2 = load chain1, loc
5825 // v2, chain3 = load chain2, loc
5826 // v3 = add v2, c
Chris Lattner125991a2008-01-24 07:57:06 +00005827 // Now we replace use of chain2 with chain1. This makes the second load
5828 // isomorphic to the one we are deleting, and thus makes this load live.
David Greenef1090292010-01-05 01:25:00 +00005829 DEBUG(dbgs() << "\nReplacing.6 ";
Chris Lattnerbbbfa992009-08-23 06:35:02 +00005830 N->dump(&DAG);
David Greenef1090292010-01-05 01:25:00 +00005831 dbgs() << "\nWith chain: ";
Chris Lattnerbbbfa992009-08-23 06:35:02 +00005832 Chain.getNode()->dump(&DAG);
David Greenef1090292010-01-05 01:25:00 +00005833 dbgs() << "\n");
Chris Lattnerf8dc0612008-02-03 06:49:24 +00005834 WorkListRemover DeadNodes(*this);
Dan Gohman475871a2008-07-27 21:46:04 +00005835 DAG.ReplaceAllUsesOfValueWith(SDValue(N, 1), Chain, &DeadNodes);
Bill Wendlingc0debad2009-01-30 23:27:35 +00005836
Chris Lattner125991a2008-01-24 07:57:06 +00005837 if (N->use_empty()) {
5838 removeFromWorkList(N);
5839 DAG.DeleteNode(N);
5840 }
Bill Wendlingc0debad2009-01-30 23:27:35 +00005841
Dan Gohman475871a2008-07-27 21:46:04 +00005842 return SDValue(N, 0); // Return N so it doesn't get rechecked!
Evan Cheng02c42852008-01-16 23:11:54 +00005843 }
Evan Cheng498f5592007-05-01 08:53:39 +00005844 } else {
5845 // Indexed loads.
Owen Anderson825b72b2009-08-11 20:47:22 +00005846 assert(N->getValueType(2) == MVT::Other && "Malformed indexed loads?");
Evan Cheng498f5592007-05-01 08:53:39 +00005847 if (N->hasNUsesOfValue(0, 0) && N->hasNUsesOfValue(0, 1)) {
Dale Johannesene8d72302009-02-06 23:05:02 +00005848 SDValue Undef = DAG.getUNDEF(N->getValueType(0));
Evan Cheng2c755ba2010-02-27 07:36:59 +00005849 DEBUG(dbgs() << "\nReplacing.7 ";
Chris Lattnerbbbfa992009-08-23 06:35:02 +00005850 N->dump(&DAG);
David Greenef1090292010-01-05 01:25:00 +00005851 dbgs() << "\nWith: ";
Chris Lattnerbbbfa992009-08-23 06:35:02 +00005852 Undef.getNode()->dump(&DAG);
David Greenef1090292010-01-05 01:25:00 +00005853 dbgs() << " and 2 other values\n");
Chris Lattnerf8dc0612008-02-03 06:49:24 +00005854 WorkListRemover DeadNodes(*this);
Dan Gohman475871a2008-07-27 21:46:04 +00005855 DAG.ReplaceAllUsesOfValueWith(SDValue(N, 0), Undef, &DeadNodes);
5856 DAG.ReplaceAllUsesOfValueWith(SDValue(N, 1),
Dale Johannesene8d72302009-02-06 23:05:02 +00005857 DAG.getUNDEF(N->getValueType(1)),
Chris Lattnerf8dc0612008-02-03 06:49:24 +00005858 &DeadNodes);
Dan Gohman475871a2008-07-27 21:46:04 +00005859 DAG.ReplaceAllUsesOfValueWith(SDValue(N, 2), Chain, &DeadNodes);
Evan Cheng02c42852008-01-16 23:11:54 +00005860 removeFromWorkList(N);
Evan Cheng02c42852008-01-16 23:11:54 +00005861 DAG.DeleteNode(N);
Dan Gohman475871a2008-07-27 21:46:04 +00005862 return SDValue(N, 0); // Return N so it doesn't get rechecked!
Evan Cheng45a7ca92007-05-01 00:38:21 +00005863 }
Evan Cheng45a7ca92007-05-01 00:38:21 +00005864 }
5865 }
Scott Michelfdc40a02009-02-17 22:15:04 +00005866
Chris Lattner01a22022005-10-10 22:04:48 +00005867 // If this load is directly stored, replace the load value with the stored
5868 // value.
5869 // TODO: Handle store large -> read small portion.
Jim Laskeyc2b19f32006-10-11 17:47:52 +00005870 // TODO: Handle TRUNCSTORE/LOADEXT
Evan Cheng9ef82ce2011-03-11 00:48:56 +00005871 if (ISD::isNormalLoad(N) && !LD->isVolatile()) {
Gabor Greifba36cb52008-08-28 21:40:38 +00005872 if (ISD::isNON_TRUNCStore(Chain.getNode())) {
Evan Cheng8b2794a2006-10-13 21:14:26 +00005873 StoreSDNode *PrevST = cast<StoreSDNode>(Chain);
5874 if (PrevST->getBasePtr() == Ptr &&
5875 PrevST->getValue().getValueType() == N->getValueType(0))
Jim Laskeyc2b19f32006-10-11 17:47:52 +00005876 return CombineTo(N, Chain.getOperand(1), Chain);
Evan Cheng8b2794a2006-10-13 21:14:26 +00005877 }
Jim Laskeyc2b19f32006-10-11 17:47:52 +00005878 }
Scott Michelfdc40a02009-02-17 22:15:04 +00005879
Evan Cheng255f20f2010-04-01 06:04:33 +00005880 // Try to infer better alignment information than the load already has.
5881 if (OptLevel != CodeGenOpt::None && LD->isUnindexed()) {
5882 if (unsigned Align = DAG.InferPtrAlignment(Ptr)) {
5883 if (Align > LD->getAlignment())
Stuart Hastingsa9011292011-02-16 16:23:55 +00005884 return DAG.getExtLoad(LD->getExtensionType(), N->getDebugLoc(),
5885 LD->getValueType(0),
Chris Lattner3d6ccfb2010-09-21 17:04:51 +00005886 Chain, Ptr, LD->getPointerInfo(),
5887 LD->getMemoryVT(),
Evan Cheng255f20f2010-04-01 06:04:33 +00005888 LD->isVolatile(), LD->isNonTemporal(), Align);
5889 }
5890 }
5891
Jim Laskey7ca56af2006-10-11 13:47:09 +00005892 if (CombinerAA) {
Jim Laskey279f0532006-09-25 16:29:54 +00005893 // Walk up chain skipping non-aliasing memory nodes.
Dan Gohman475871a2008-07-27 21:46:04 +00005894 SDValue BetterChain = FindBetterChain(N, Chain);
Scott Michelfdc40a02009-02-17 22:15:04 +00005895
Jim Laskey6ff23e52006-10-04 16:53:27 +00005896 // If there is a better chain.
Jim Laskey279f0532006-09-25 16:29:54 +00005897 if (Chain != BetterChain) {
Dan Gohman475871a2008-07-27 21:46:04 +00005898 SDValue ReplLoad;
Jim Laskeyc2b19f32006-10-11 17:47:52 +00005899
Jim Laskey279f0532006-09-25 16:29:54 +00005900 // Replace the chain to void dependency.
Jim Laskeyc2b19f32006-10-11 17:47:52 +00005901 if (LD->getExtensionType() == ISD::NON_EXTLOAD) {
Bill Wendlingc0debad2009-01-30 23:27:35 +00005902 ReplLoad = DAG.getLoad(N->getValueType(0), LD->getDebugLoc(),
Chris Lattnerfa459012010-09-21 16:08:50 +00005903 BetterChain, Ptr, LD->getPointerInfo(),
David Greene1e559442010-02-15 17:00:31 +00005904 LD->isVolatile(), LD->isNonTemporal(),
5905 LD->getAlignment());
Jim Laskeyc2b19f32006-10-11 17:47:52 +00005906 } else {
Stuart Hastingsa9011292011-02-16 16:23:55 +00005907 ReplLoad = DAG.getExtLoad(LD->getExtensionType(), LD->getDebugLoc(),
5908 LD->getValueType(0),
Chris Lattnerfa459012010-09-21 16:08:50 +00005909 BetterChain, Ptr, LD->getPointerInfo(),
Dan Gohmanb625f2f2008-01-30 00:15:11 +00005910 LD->getMemoryVT(),
Scott Michelfdc40a02009-02-17 22:15:04 +00005911 LD->isVolatile(),
David Greene1e559442010-02-15 17:00:31 +00005912 LD->isNonTemporal(),
Christopher Lamb95c218a2007-04-22 23:15:30 +00005913 LD->getAlignment());
Jim Laskeyc2b19f32006-10-11 17:47:52 +00005914 }
Jim Laskey279f0532006-09-25 16:29:54 +00005915
Jim Laskey6ff23e52006-10-04 16:53:27 +00005916 // Create token factor to keep old chain connected.
Bill Wendlingc0debad2009-01-30 23:27:35 +00005917 SDValue Token = DAG.getNode(ISD::TokenFactor, N->getDebugLoc(),
Owen Anderson825b72b2009-08-11 20:47:22 +00005918 MVT::Other, Chain, ReplLoad.getValue(1));
Wesley Peckbf17cfa2010-11-23 03:31:01 +00005919
Nate Begemanb6aef5c2009-09-15 00:18:30 +00005920 // Make sure the new and old chains are cleaned up.
5921 AddToWorkList(Token.getNode());
Wesley Peckbf17cfa2010-11-23 03:31:01 +00005922
Jim Laskey274062c2006-10-13 23:32:28 +00005923 // Replace uses with load result and token factor. Don't add users
5924 // to work list.
5925 return CombineTo(N, ReplLoad.getValue(0), Token, false);
Jim Laskey279f0532006-09-25 16:29:54 +00005926 }
5927 }
5928
Evan Cheng7fc033a2006-11-03 03:06:21 +00005929 // Try transforming N to an indexed load.
Evan Chengbbd6f6e2006-11-07 09:03:05 +00005930 if (CombineToPreIndexedLoadStore(N) || CombineToPostIndexedLoadStore(N))
Dan Gohman475871a2008-07-27 21:46:04 +00005931 return SDValue(N, 0);
Evan Cheng7fc033a2006-11-03 03:06:21 +00005932
Dan Gohman475871a2008-07-27 21:46:04 +00005933 return SDValue();
Chris Lattner01a22022005-10-10 22:04:48 +00005934}
5935
Chris Lattner2392ae72010-04-15 04:48:01 +00005936/// CheckForMaskedLoad - Check to see if V is (and load (ptr), imm), where the
5937/// load is having specific bytes cleared out. If so, return the byte size
5938/// being masked out and the shift amount.
5939static std::pair<unsigned, unsigned>
5940CheckForMaskedLoad(SDValue V, SDValue Ptr, SDValue Chain) {
5941 std::pair<unsigned, unsigned> Result(0, 0);
Wesley Peckbf17cfa2010-11-23 03:31:01 +00005942
Chris Lattner2392ae72010-04-15 04:48:01 +00005943 // Check for the structure we're looking for.
5944 if (V->getOpcode() != ISD::AND ||
5945 !isa<ConstantSDNode>(V->getOperand(1)) ||
5946 !ISD::isNormalLoad(V->getOperand(0).getNode()))
5947 return Result;
Wesley Peckbf17cfa2010-11-23 03:31:01 +00005948
Chris Lattnere6987582010-04-15 06:10:49 +00005949 // Check the chain and pointer.
Chris Lattner2392ae72010-04-15 04:48:01 +00005950 LoadSDNode *LD = cast<LoadSDNode>(V->getOperand(0));
Chris Lattnere6987582010-04-15 06:10:49 +00005951 if (LD->getBasePtr() != Ptr) return Result; // Not from same pointer.
Wesley Peckbf17cfa2010-11-23 03:31:01 +00005952
Chris Lattnere6987582010-04-15 06:10:49 +00005953 // The store should be chained directly to the load or be an operand of a
5954 // tokenfactor.
5955 if (LD == Chain.getNode())
5956 ; // ok.
5957 else if (Chain->getOpcode() != ISD::TokenFactor)
5958 return Result; // Fail.
5959 else {
5960 bool isOk = false;
5961 for (unsigned i = 0, e = Chain->getNumOperands(); i != e; ++i)
5962 if (Chain->getOperand(i).getNode() == LD) {
5963 isOk = true;
5964 break;
5965 }
5966 if (!isOk) return Result;
5967 }
Wesley Peckbf17cfa2010-11-23 03:31:01 +00005968
Chris Lattner2392ae72010-04-15 04:48:01 +00005969 // This only handles simple types.
5970 if (V.getValueType() != MVT::i16 &&
5971 V.getValueType() != MVT::i32 &&
5972 V.getValueType() != MVT::i64)
5973 return Result;
5974
5975 // Check the constant mask. Invert it so that the bits being masked out are
5976 // 0 and the bits being kept are 1. Use getSExtValue so that leading bits
5977 // follow the sign bit for uniformity.
5978 uint64_t NotMask = ~cast<ConstantSDNode>(V->getOperand(1))->getSExtValue();
5979 unsigned NotMaskLZ = CountLeadingZeros_64(NotMask);
5980 if (NotMaskLZ & 7) return Result; // Must be multiple of a byte.
5981 unsigned NotMaskTZ = CountTrailingZeros_64(NotMask);
5982 if (NotMaskTZ & 7) return Result; // Must be multiple of a byte.
5983 if (NotMaskLZ == 64) return Result; // All zero mask.
Wesley Peckbf17cfa2010-11-23 03:31:01 +00005984
Chris Lattner2392ae72010-04-15 04:48:01 +00005985 // See if we have a continuous run of bits. If so, we have 0*1+0*
5986 if (CountTrailingOnes_64(NotMask >> NotMaskTZ)+NotMaskTZ+NotMaskLZ != 64)
5987 return Result;
5988
5989 // Adjust NotMaskLZ down to be from the actual size of the int instead of i64.
5990 if (V.getValueType() != MVT::i64 && NotMaskLZ)
5991 NotMaskLZ -= 64-V.getValueSizeInBits();
Wesley Peckbf17cfa2010-11-23 03:31:01 +00005992
Chris Lattner2392ae72010-04-15 04:48:01 +00005993 unsigned MaskedBytes = (V.getValueSizeInBits()-NotMaskLZ-NotMaskTZ)/8;
5994 switch (MaskedBytes) {
Wesley Peckbf17cfa2010-11-23 03:31:01 +00005995 case 1:
5996 case 2:
Chris Lattner2392ae72010-04-15 04:48:01 +00005997 case 4: break;
5998 default: return Result; // All one mask, or 5-byte mask.
5999 }
Wesley Peckbf17cfa2010-11-23 03:31:01 +00006000
Chris Lattner2392ae72010-04-15 04:48:01 +00006001 // Verify that the first bit starts at a multiple of mask so that the access
6002 // is aligned the same as the access width.
6003 if (NotMaskTZ && NotMaskTZ/8 % MaskedBytes) return Result;
Wesley Peckbf17cfa2010-11-23 03:31:01 +00006004
Chris Lattner2392ae72010-04-15 04:48:01 +00006005 Result.first = MaskedBytes;
6006 Result.second = NotMaskTZ/8;
6007 return Result;
6008}
6009
6010
6011/// ShrinkLoadReplaceStoreWithStore - Check to see if IVal is something that
6012/// provides a value as specified by MaskInfo. If so, replace the specified
6013/// store with a narrower store of truncated IVal.
6014static SDNode *
6015ShrinkLoadReplaceStoreWithStore(const std::pair<unsigned, unsigned> &MaskInfo,
6016 SDValue IVal, StoreSDNode *St,
6017 DAGCombiner *DC) {
6018 unsigned NumBytes = MaskInfo.first;
6019 unsigned ByteShift = MaskInfo.second;
6020 SelectionDAG &DAG = DC->getDAG();
Wesley Peckbf17cfa2010-11-23 03:31:01 +00006021
Chris Lattner2392ae72010-04-15 04:48:01 +00006022 // Check to see if IVal is all zeros in the part being masked in by the 'or'
6023 // that uses this. If not, this is not a replacement.
6024 APInt Mask = ~APInt::getBitsSet(IVal.getValueSizeInBits(),
6025 ByteShift*8, (ByteShift+NumBytes)*8);
6026 if (!DAG.MaskedValueIsZero(IVal, Mask)) return 0;
Wesley Peckbf17cfa2010-11-23 03:31:01 +00006027
Chris Lattner2392ae72010-04-15 04:48:01 +00006028 // Check that it is legal on the target to do this. It is legal if the new
6029 // VT we're shrinking to (i8/i16/i32) is legal or we're still before type
6030 // legalization.
6031 MVT VT = MVT::getIntegerVT(NumBytes*8);
6032 if (!DC->isTypeLegal(VT))
6033 return 0;
Wesley Peckbf17cfa2010-11-23 03:31:01 +00006034
Chris Lattner2392ae72010-04-15 04:48:01 +00006035 // Okay, we can do this! Replace the 'St' store with a store of IVal that is
6036 // shifted by ByteShift and truncated down to NumBytes.
6037 if (ByteShift)
6038 IVal = DAG.getNode(ISD::SRL, IVal->getDebugLoc(), IVal.getValueType(), IVal,
Owen Anderson95771af2011-02-25 21:41:48 +00006039 DAG.getConstant(ByteShift*8,
6040 DC->getShiftAmountTy(IVal.getValueType())));
Chris Lattner2392ae72010-04-15 04:48:01 +00006041
6042 // Figure out the offset for the store and the alignment of the access.
6043 unsigned StOffset;
6044 unsigned NewAlign = St->getAlignment();
6045
6046 if (DAG.getTargetLoweringInfo().isLittleEndian())
6047 StOffset = ByteShift;
6048 else
6049 StOffset = IVal.getValueType().getStoreSize() - ByteShift - NumBytes;
Wesley Peckbf17cfa2010-11-23 03:31:01 +00006050
Chris Lattner2392ae72010-04-15 04:48:01 +00006051 SDValue Ptr = St->getBasePtr();
6052 if (StOffset) {
6053 Ptr = DAG.getNode(ISD::ADD, IVal->getDebugLoc(), Ptr.getValueType(),
6054 Ptr, DAG.getConstant(StOffset, Ptr.getValueType()));
6055 NewAlign = MinAlign(NewAlign, StOffset);
6056 }
Wesley Peckbf17cfa2010-11-23 03:31:01 +00006057
Chris Lattner2392ae72010-04-15 04:48:01 +00006058 // Truncate down to the new size.
6059 IVal = DAG.getNode(ISD::TRUNCATE, IVal->getDebugLoc(), VT, IVal);
Wesley Peckbf17cfa2010-11-23 03:31:01 +00006060
Chris Lattner2392ae72010-04-15 04:48:01 +00006061 ++OpsNarrowed;
Wesley Peckbf17cfa2010-11-23 03:31:01 +00006062 return DAG.getStore(St->getChain(), St->getDebugLoc(), IVal, Ptr,
Chris Lattner6229d0a2010-09-21 18:41:36 +00006063 St->getPointerInfo().getWithOffset(StOffset),
Chris Lattner2392ae72010-04-15 04:48:01 +00006064 false, false, NewAlign).getNode();
6065}
6066
Evan Cheng8b944d32009-05-28 00:35:15 +00006067
6068/// ReduceLoadOpStoreWidth - Look for sequence of load / op / store where op is
6069/// one of 'or', 'xor', and 'and' of immediates. If 'op' is only touching some
6070/// of the loaded bits, try narrowing the load and store if it would end up
6071/// being a win for performance or code size.
6072SDValue DAGCombiner::ReduceLoadOpStoreWidth(SDNode *N) {
6073 StoreSDNode *ST = cast<StoreSDNode>(N);
Evan Chengcdcecc02009-05-28 18:41:02 +00006074 if (ST->isVolatile())
6075 return SDValue();
6076
Evan Cheng8b944d32009-05-28 00:35:15 +00006077 SDValue Chain = ST->getChain();
6078 SDValue Value = ST->getValue();
6079 SDValue Ptr = ST->getBasePtr();
Owen Andersone50ed302009-08-10 22:56:29 +00006080 EVT VT = Value.getValueType();
Evan Cheng8b944d32009-05-28 00:35:15 +00006081
6082 if (ST->isTruncatingStore() || VT.isVector() || !Value.hasOneUse())
Evan Chengcdcecc02009-05-28 18:41:02 +00006083 return SDValue();
Evan Cheng8b944d32009-05-28 00:35:15 +00006084
6085 unsigned Opc = Value.getOpcode();
Wesley Peckbf17cfa2010-11-23 03:31:01 +00006086
Chris Lattner2392ae72010-04-15 04:48:01 +00006087 // If this is "store (or X, Y), P" and X is "(and (load P), cst)", where cst
6088 // is a byte mask indicating a consecutive number of bytes, check to see if
6089 // Y is known to provide just those bytes. If so, we try to replace the
6090 // load + replace + store sequence with a single (narrower) store, which makes
6091 // the load dead.
6092 if (Opc == ISD::OR) {
6093 std::pair<unsigned, unsigned> MaskedLoad;
6094 MaskedLoad = CheckForMaskedLoad(Value.getOperand(0), Ptr, Chain);
6095 if (MaskedLoad.first)
6096 if (SDNode *NewST = ShrinkLoadReplaceStoreWithStore(MaskedLoad,
6097 Value.getOperand(1), ST,this))
6098 return SDValue(NewST, 0);
Wesley Peckbf17cfa2010-11-23 03:31:01 +00006099
Chris Lattner2392ae72010-04-15 04:48:01 +00006100 // Or is commutative, so try swapping X and Y.
6101 MaskedLoad = CheckForMaskedLoad(Value.getOperand(1), Ptr, Chain);
6102 if (MaskedLoad.first)
6103 if (SDNode *NewST = ShrinkLoadReplaceStoreWithStore(MaskedLoad,
6104 Value.getOperand(0), ST,this))
6105 return SDValue(NewST, 0);
6106 }
Wesley Peckbf17cfa2010-11-23 03:31:01 +00006107
Evan Cheng8b944d32009-05-28 00:35:15 +00006108 if ((Opc != ISD::OR && Opc != ISD::XOR && Opc != ISD::AND) ||
6109 Value.getOperand(1).getOpcode() != ISD::Constant)
Evan Chengcdcecc02009-05-28 18:41:02 +00006110 return SDValue();
Evan Cheng8b944d32009-05-28 00:35:15 +00006111
6112 SDValue N0 = Value.getOperand(0);
Dan Gohman24bde5b2010-09-02 21:18:42 +00006113 if (ISD::isNormalLoad(N0.getNode()) && N0.hasOneUse() &&
6114 Chain == SDValue(N0.getNode(), 1)) {
Evan Cheng8b944d32009-05-28 00:35:15 +00006115 LoadSDNode *LD = cast<LoadSDNode>(N0);
Chris Lattnerfa459012010-09-21 16:08:50 +00006116 if (LD->getBasePtr() != Ptr ||
6117 LD->getPointerInfo().getAddrSpace() !=
6118 ST->getPointerInfo().getAddrSpace())
Evan Chengcdcecc02009-05-28 18:41:02 +00006119 return SDValue();
Evan Cheng8b944d32009-05-28 00:35:15 +00006120
6121 // Find the type to narrow it the load / op / store to.
6122 SDValue N1 = Value.getOperand(1);
6123 unsigned BitWidth = N1.getValueSizeInBits();
6124 APInt Imm = cast<ConstantSDNode>(N1)->getAPIntValue();
6125 if (Opc == ISD::AND)
6126 Imm ^= APInt::getAllOnesValue(BitWidth);
Evan Chengd3c76bb2009-05-28 23:52:18 +00006127 if (Imm == 0 || Imm.isAllOnesValue())
6128 return SDValue();
Evan Cheng8b944d32009-05-28 00:35:15 +00006129 unsigned ShAmt = Imm.countTrailingZeros();
6130 unsigned MSB = BitWidth - Imm.countLeadingZeros() - 1;
6131 unsigned NewBW = NextPowerOf2(MSB - ShAmt);
Owen Anderson23b9b192009-08-12 00:36:31 +00006132 EVT NewVT = EVT::getIntegerVT(*DAG.getContext(), NewBW);
Evan Cheng8b944d32009-05-28 00:35:15 +00006133 while (NewBW < BitWidth &&
Evan Chengcdcecc02009-05-28 18:41:02 +00006134 !(TLI.isOperationLegalOrCustom(Opc, NewVT) &&
Evan Cheng8b944d32009-05-28 00:35:15 +00006135 TLI.isNarrowingProfitable(VT, NewVT))) {
6136 NewBW = NextPowerOf2(NewBW);
Owen Anderson23b9b192009-08-12 00:36:31 +00006137 NewVT = EVT::getIntegerVT(*DAG.getContext(), NewBW);
Evan Cheng8b944d32009-05-28 00:35:15 +00006138 }
Evan Chengcdcecc02009-05-28 18:41:02 +00006139 if (NewBW >= BitWidth)
6140 return SDValue();
Evan Cheng8b944d32009-05-28 00:35:15 +00006141
6142 // If the lsb changed does not start at the type bitwidth boundary,
6143 // start at the previous one.
6144 if (ShAmt % NewBW)
6145 ShAmt = (((ShAmt + NewBW - 1) / NewBW) * NewBW) - NewBW;
6146 APInt Mask = APInt::getBitsSet(BitWidth, ShAmt, ShAmt + NewBW);
6147 if ((Imm & Mask) == Imm) {
6148 APInt NewImm = (Imm & Mask).lshr(ShAmt).trunc(NewBW);
6149 if (Opc == ISD::AND)
6150 NewImm ^= APInt::getAllOnesValue(NewBW);
6151 uint64_t PtrOff = ShAmt / 8;
6152 // For big endian targets, we need to adjust the offset to the pointer to
6153 // load the correct bytes.
6154 if (TLI.isBigEndian())
Evan Chengcdcecc02009-05-28 18:41:02 +00006155 PtrOff = (BitWidth + 7 - NewBW) / 8 - PtrOff;
Evan Cheng8b944d32009-05-28 00:35:15 +00006156
6157 unsigned NewAlign = MinAlign(LD->getAlignment(), PtrOff);
Chris Lattner2392ae72010-04-15 04:48:01 +00006158 const Type *NewVTTy = NewVT.getTypeForEVT(*DAG.getContext());
6159 if (NewAlign < TLI.getTargetData()->getABITypeAlignment(NewVTTy))
Evan Chengcdcecc02009-05-28 18:41:02 +00006160 return SDValue();
6161
Evan Cheng8b944d32009-05-28 00:35:15 +00006162 SDValue NewPtr = DAG.getNode(ISD::ADD, LD->getDebugLoc(),
6163 Ptr.getValueType(), Ptr,
6164 DAG.getConstant(PtrOff, Ptr.getValueType()));
6165 SDValue NewLD = DAG.getLoad(NewVT, N0.getDebugLoc(),
6166 LD->getChain(), NewPtr,
Chris Lattnerfa459012010-09-21 16:08:50 +00006167 LD->getPointerInfo().getWithOffset(PtrOff),
David Greene1e559442010-02-15 17:00:31 +00006168 LD->isVolatile(), LD->isNonTemporal(),
6169 NewAlign);
Evan Cheng8b944d32009-05-28 00:35:15 +00006170 SDValue NewVal = DAG.getNode(Opc, Value.getDebugLoc(), NewVT, NewLD,
6171 DAG.getConstant(NewImm, NewVT));
6172 SDValue NewST = DAG.getStore(Chain, N->getDebugLoc(),
6173 NewVal, NewPtr,
Chris Lattnerfa459012010-09-21 16:08:50 +00006174 ST->getPointerInfo().getWithOffset(PtrOff),
David Greene1e559442010-02-15 17:00:31 +00006175 false, false, NewAlign);
Evan Cheng8b944d32009-05-28 00:35:15 +00006176
6177 AddToWorkList(NewPtr.getNode());
6178 AddToWorkList(NewLD.getNode());
6179 AddToWorkList(NewVal.getNode());
6180 WorkListRemover DeadNodes(*this);
6181 DAG.ReplaceAllUsesOfValueWith(N0.getValue(1), NewLD.getValue(1),
6182 &DeadNodes);
6183 ++OpsNarrowed;
6184 return NewST;
6185 }
6186 }
6187
Evan Chengcdcecc02009-05-28 18:41:02 +00006188 return SDValue();
Evan Cheng8b944d32009-05-28 00:35:15 +00006189}
6190
Evan Cheng31959b12011-02-02 01:06:55 +00006191/// TransformFPLoadStorePair - For a given floating point load / store pair,
6192/// if the load value isn't used by any other operations, then consider
6193/// transforming the pair to integer load / store operations if the target
6194/// deems the transformation profitable.
6195SDValue DAGCombiner::TransformFPLoadStorePair(SDNode *N) {
6196 StoreSDNode *ST = cast<StoreSDNode>(N);
6197 SDValue Chain = ST->getChain();
6198 SDValue Value = ST->getValue();
6199 if (ISD::isNormalStore(ST) && ISD::isNormalLoad(Value.getNode()) &&
6200 Value.hasOneUse() &&
6201 Chain == SDValue(Value.getNode(), 1)) {
6202 LoadSDNode *LD = cast<LoadSDNode>(Value);
6203 EVT VT = LD->getMemoryVT();
6204 if (!VT.isFloatingPoint() ||
6205 VT != ST->getMemoryVT() ||
6206 LD->isNonTemporal() ||
6207 ST->isNonTemporal() ||
6208 LD->getPointerInfo().getAddrSpace() != 0 ||
6209 ST->getPointerInfo().getAddrSpace() != 0)
6210 return SDValue();
6211
6212 EVT IntVT = EVT::getIntegerVT(*DAG.getContext(), VT.getSizeInBits());
6213 if (!TLI.isOperationLegal(ISD::LOAD, IntVT) ||
6214 !TLI.isOperationLegal(ISD::STORE, IntVT) ||
6215 !TLI.isDesirableToTransformToIntegerOp(ISD::LOAD, VT) ||
6216 !TLI.isDesirableToTransformToIntegerOp(ISD::STORE, VT))
6217 return SDValue();
6218
6219 unsigned LDAlign = LD->getAlignment();
6220 unsigned STAlign = ST->getAlignment();
6221 const Type *IntVTTy = IntVT.getTypeForEVT(*DAG.getContext());
6222 unsigned ABIAlign = TLI.getTargetData()->getABITypeAlignment(IntVTTy);
6223 if (LDAlign < ABIAlign || STAlign < ABIAlign)
6224 return SDValue();
6225
6226 SDValue NewLD = DAG.getLoad(IntVT, Value.getDebugLoc(),
6227 LD->getChain(), LD->getBasePtr(),
6228 LD->getPointerInfo(),
6229 false, false, LDAlign);
6230
6231 SDValue NewST = DAG.getStore(NewLD.getValue(1), N->getDebugLoc(),
6232 NewLD, ST->getBasePtr(),
6233 ST->getPointerInfo(),
6234 false, false, STAlign);
6235
6236 AddToWorkList(NewLD.getNode());
6237 AddToWorkList(NewST.getNode());
6238 WorkListRemover DeadNodes(*this);
6239 DAG.ReplaceAllUsesOfValueWith(Value.getValue(1), NewLD.getValue(1),
6240 &DeadNodes);
6241 ++LdStFP2Int;
6242 return NewST;
6243 }
6244
6245 return SDValue();
6246}
6247
Dan Gohman475871a2008-07-27 21:46:04 +00006248SDValue DAGCombiner::visitSTORE(SDNode *N) {
Evan Cheng8b2794a2006-10-13 21:14:26 +00006249 StoreSDNode *ST = cast<StoreSDNode>(N);
Dan Gohman475871a2008-07-27 21:46:04 +00006250 SDValue Chain = ST->getChain();
6251 SDValue Value = ST->getValue();
6252 SDValue Ptr = ST->getBasePtr();
Scott Michelfdc40a02009-02-17 22:15:04 +00006253
Evan Cheng59d5b682007-05-07 21:27:48 +00006254 // If this is a store of a bit convert, store the input value if the
Evan Cheng2c4f9432007-05-09 21:49:47 +00006255 // resultant store does not need a higher alignment than the original.
Wesley Peckbf17cfa2010-11-23 03:31:01 +00006256 if (Value.getOpcode() == ISD::BITCAST && !ST->isTruncatingStore() &&
Chris Lattnerddf89562008-01-17 19:59:44 +00006257 ST->isUnindexed()) {
Dan Gohman1ba519b2009-02-20 23:29:13 +00006258 unsigned OrigAlign = ST->getAlignment();
Owen Andersone50ed302009-08-10 22:56:29 +00006259 EVT SVT = Value.getOperand(0).getValueType();
Dan Gohman1ba519b2009-02-20 23:29:13 +00006260 unsigned Align = TLI.getTargetData()->
Owen Anderson23b9b192009-08-12 00:36:31 +00006261 getABITypeAlignment(SVT.getTypeForEVT(*DAG.getContext()));
Duncan Sandsd4b9c172008-06-13 19:07:40 +00006262 if (Align <= OrigAlign &&
Duncan Sands25cf2272008-11-24 14:53:14 +00006263 ((!LegalOperations && !ST->isVolatile()) ||
Dan Gohmanf560ffa2009-01-28 17:46:25 +00006264 TLI.isOperationLegalOrCustom(ISD::STORE, SVT)))
Bill Wendlingc144a572009-01-30 23:36:47 +00006265 return DAG.getStore(Chain, N->getDebugLoc(), Value.getOperand(0),
Chris Lattner6229d0a2010-09-21 18:41:36 +00006266 Ptr, ST->getPointerInfo(), ST->isVolatile(),
David Greene1e559442010-02-15 17:00:31 +00006267 ST->isNonTemporal(), OrigAlign);
Jim Laskey279f0532006-09-25 16:29:54 +00006268 }
Owen Andersona34d9362011-04-14 17:30:49 +00006269
Chris Lattnerb3452ea2011-04-09 02:32:02 +00006270 // Turn 'store undef, Ptr' -> nothing.
6271 if (Value.getOpcode() == ISD::UNDEF && ST->isUnindexed())
6272 return Chain;
Duncan Sandsd4b9c172008-06-13 19:07:40 +00006273
Nate Begeman2cbba892006-12-11 02:23:46 +00006274 // Turn 'store float 1.0, Ptr' -> 'store int 0x12345678, Ptr'
Nate Begeman2cbba892006-12-11 02:23:46 +00006275 if (ConstantFPSDNode *CFP = dyn_cast<ConstantFPSDNode>(Value)) {
Duncan Sandsd4b9c172008-06-13 19:07:40 +00006276 // NOTE: If the original store is volatile, this transform must not increase
6277 // the number of stores. For example, on x86-32 an f64 can be stored in one
6278 // processor operation but an i64 (which is not legal) requires two. So the
6279 // transform should not be done in this case.
Evan Cheng25ece662006-12-11 17:25:19 +00006280 if (Value.getOpcode() != ISD::TargetConstantFP) {
Dan Gohman475871a2008-07-27 21:46:04 +00006281 SDValue Tmp;
Owen Anderson825b72b2009-08-11 20:47:22 +00006282 switch (CFP->getValueType(0).getSimpleVT().SimpleTy) {
Torok Edwinc23197a2009-07-14 16:55:14 +00006283 default: llvm_unreachable("Unknown FP type");
Owen Anderson825b72b2009-08-11 20:47:22 +00006284 case MVT::f80: // We don't do this for these yet.
6285 case MVT::f128:
6286 case MVT::ppcf128:
Dale Johannesenc7b21d52007-09-18 18:36:59 +00006287 break;
Owen Anderson825b72b2009-08-11 20:47:22 +00006288 case MVT::f32:
Chris Lattner2392ae72010-04-15 04:48:01 +00006289 if ((isTypeLegal(MVT::i32) && !LegalOperations && !ST->isVolatile()) ||
Owen Anderson825b72b2009-08-11 20:47:22 +00006290 TLI.isOperationLegalOrCustom(ISD::STORE, MVT::i32)) {
Dale Johannesen9d5f4562007-09-12 03:30:33 +00006291 Tmp = DAG.getConstant((uint32_t)CFP->getValueAPF().
Owen Anderson825b72b2009-08-11 20:47:22 +00006292 bitcastToAPInt().getZExtValue(), MVT::i32);
Bill Wendlingc144a572009-01-30 23:36:47 +00006293 return DAG.getStore(Chain, N->getDebugLoc(), Tmp,
Chris Lattner6229d0a2010-09-21 18:41:36 +00006294 Ptr, ST->getPointerInfo(), ST->isVolatile(),
David Greene1e559442010-02-15 17:00:31 +00006295 ST->isNonTemporal(), ST->getAlignment());
Chris Lattner62be1a72006-12-12 04:16:14 +00006296 }
6297 break;
Owen Anderson825b72b2009-08-11 20:47:22 +00006298 case MVT::f64:
Chris Lattner2392ae72010-04-15 04:48:01 +00006299 if ((TLI.isTypeLegal(MVT::i64) && !LegalOperations &&
Dan Gohmanf560ffa2009-01-28 17:46:25 +00006300 !ST->isVolatile()) ||
Owen Anderson825b72b2009-08-11 20:47:22 +00006301 TLI.isOperationLegalOrCustom(ISD::STORE, MVT::i64)) {
Dale Johannesen7111b022008-10-09 18:53:47 +00006302 Tmp = DAG.getConstant(CFP->getValueAPF().bitcastToAPInt().
Owen Anderson825b72b2009-08-11 20:47:22 +00006303 getZExtValue(), MVT::i64);
Bill Wendlingc144a572009-01-30 23:36:47 +00006304 return DAG.getStore(Chain, N->getDebugLoc(), Tmp,
Chris Lattner6229d0a2010-09-21 18:41:36 +00006305 Ptr, ST->getPointerInfo(), ST->isVolatile(),
David Greene1e559442010-02-15 17:00:31 +00006306 ST->isNonTemporal(), ST->getAlignment());
Chris Lattnerb3452ea2011-04-09 02:32:02 +00006307 }
Owen Andersona34d9362011-04-14 17:30:49 +00006308
Chris Lattnerb3452ea2011-04-09 02:32:02 +00006309 if (!ST->isVolatile() &&
6310 TLI.isOperationLegalOrCustom(ISD::STORE, MVT::i32)) {
Duncan Sandsdc846502007-10-28 12:59:45 +00006311 // Many FP stores are not made apparent until after legalize, e.g. for
Chris Lattner62be1a72006-12-12 04:16:14 +00006312 // argument passing. Since this is so common, custom legalize the
6313 // 64-bit integer store into two 32-bit stores.
Dale Johannesen7111b022008-10-09 18:53:47 +00006314 uint64_t Val = CFP->getValueAPF().bitcastToAPInt().getZExtValue();
Owen Anderson825b72b2009-08-11 20:47:22 +00006315 SDValue Lo = DAG.getConstant(Val & 0xFFFFFFFF, MVT::i32);
6316 SDValue Hi = DAG.getConstant(Val >> 32, MVT::i32);
Duncan Sands0753fc12008-02-11 10:37:04 +00006317 if (TLI.isBigEndian()) std::swap(Lo, Hi);
Chris Lattner62be1a72006-12-12 04:16:14 +00006318
Dan Gohmand6fd1bc2007-07-09 22:18:38 +00006319 unsigned Alignment = ST->getAlignment();
6320 bool isVolatile = ST->isVolatile();
David Greene1e559442010-02-15 17:00:31 +00006321 bool isNonTemporal = ST->isNonTemporal();
Dan Gohmand6fd1bc2007-07-09 22:18:38 +00006322
Bill Wendlingc144a572009-01-30 23:36:47 +00006323 SDValue St0 = DAG.getStore(Chain, ST->getDebugLoc(), Lo,
Chris Lattner6229d0a2010-09-21 18:41:36 +00006324 Ptr, ST->getPointerInfo(),
David Greene1e559442010-02-15 17:00:31 +00006325 isVolatile, isNonTemporal,
6326 ST->getAlignment());
Bill Wendlingc144a572009-01-30 23:36:47 +00006327 Ptr = DAG.getNode(ISD::ADD, N->getDebugLoc(), Ptr.getValueType(), Ptr,
Chris Lattner62be1a72006-12-12 04:16:14 +00006328 DAG.getConstant(4, Ptr.getValueType()));
Duncan Sandsdc846502007-10-28 12:59:45 +00006329 Alignment = MinAlign(Alignment, 4U);
Bill Wendlingc144a572009-01-30 23:36:47 +00006330 SDValue St1 = DAG.getStore(Chain, ST->getDebugLoc(), Hi,
Chris Lattner6229d0a2010-09-21 18:41:36 +00006331 Ptr, ST->getPointerInfo().getWithOffset(4),
6332 isVolatile, isNonTemporal,
David Greene1e559442010-02-15 17:00:31 +00006333 Alignment);
Owen Anderson825b72b2009-08-11 20:47:22 +00006334 return DAG.getNode(ISD::TokenFactor, N->getDebugLoc(), MVT::Other,
Bill Wendlingc144a572009-01-30 23:36:47 +00006335 St0, St1);
Chris Lattner62be1a72006-12-12 04:16:14 +00006336 }
Bill Wendlingc144a572009-01-30 23:36:47 +00006337
Chris Lattner62be1a72006-12-12 04:16:14 +00006338 break;
Evan Cheng25ece662006-12-11 17:25:19 +00006339 }
Nate Begeman2cbba892006-12-11 02:23:46 +00006340 }
Nate Begeman2cbba892006-12-11 02:23:46 +00006341 }
6342
Evan Cheng255f20f2010-04-01 06:04:33 +00006343 // Try to infer better alignment information than the store already has.
6344 if (OptLevel != CodeGenOpt::None && ST->isUnindexed()) {
6345 if (unsigned Align = DAG.InferPtrAlignment(Ptr)) {
6346 if (Align > ST->getAlignment())
6347 return DAG.getTruncStore(Chain, N->getDebugLoc(), Value,
Chris Lattnerda2d8e12010-09-21 17:42:31 +00006348 Ptr, ST->getPointerInfo(), ST->getMemoryVT(),
Evan Cheng255f20f2010-04-01 06:04:33 +00006349 ST->isVolatile(), ST->isNonTemporal(), Align);
6350 }
6351 }
6352
Evan Cheng31959b12011-02-02 01:06:55 +00006353 // Try transforming a pair floating point load / store ops to integer
6354 // load / store ops.
6355 SDValue NewST = TransformFPLoadStorePair(N);
6356 if (NewST.getNode())
6357 return NewST;
6358
Scott Michelfdc40a02009-02-17 22:15:04 +00006359 if (CombinerAA) {
Jim Laskey279f0532006-09-25 16:29:54 +00006360 // Walk up chain skipping non-aliasing memory nodes.
Dan Gohman475871a2008-07-27 21:46:04 +00006361 SDValue BetterChain = FindBetterChain(N, Chain);
Scott Michelfdc40a02009-02-17 22:15:04 +00006362
Jim Laskey6ff23e52006-10-04 16:53:27 +00006363 // If there is a better chain.
Jim Laskey279f0532006-09-25 16:29:54 +00006364 if (Chain != BetterChain) {
Dan Gohman475871a2008-07-27 21:46:04 +00006365 SDValue ReplStore;
Nate Begemanb6aef5c2009-09-15 00:18:30 +00006366
6367 // Replace the chain to avoid dependency.
Jim Laskeyd4edf2c2006-10-14 12:14:27 +00006368 if (ST->isTruncatingStore()) {
Bill Wendlingc144a572009-01-30 23:36:47 +00006369 ReplStore = DAG.getTruncStore(BetterChain, N->getDebugLoc(), Value, Ptr,
Chris Lattnerda2d8e12010-09-21 17:42:31 +00006370 ST->getPointerInfo(),
David Greene1e559442010-02-15 17:00:31 +00006371 ST->getMemoryVT(), ST->isVolatile(),
6372 ST->isNonTemporal(), ST->getAlignment());
Jim Laskeyd4edf2c2006-10-14 12:14:27 +00006373 } else {
Bill Wendlingc144a572009-01-30 23:36:47 +00006374 ReplStore = DAG.getStore(BetterChain, N->getDebugLoc(), Value, Ptr,
Chris Lattner6229d0a2010-09-21 18:41:36 +00006375 ST->getPointerInfo(),
David Greene1e559442010-02-15 17:00:31 +00006376 ST->isVolatile(), ST->isNonTemporal(),
6377 ST->getAlignment());
Jim Laskeyd4edf2c2006-10-14 12:14:27 +00006378 }
Scott Michelfdc40a02009-02-17 22:15:04 +00006379
Jim Laskey279f0532006-09-25 16:29:54 +00006380 // Create token to keep both nodes around.
Bill Wendlingc144a572009-01-30 23:36:47 +00006381 SDValue Token = DAG.getNode(ISD::TokenFactor, N->getDebugLoc(),
Owen Anderson825b72b2009-08-11 20:47:22 +00006382 MVT::Other, Chain, ReplStore);
Bill Wendlingc144a572009-01-30 23:36:47 +00006383
Nate Begemanb6aef5c2009-09-15 00:18:30 +00006384 // Make sure the new and old chains are cleaned up.
6385 AddToWorkList(Token.getNode());
6386
Jim Laskey274062c2006-10-13 23:32:28 +00006387 // Don't add users to work list.
6388 return CombineTo(N, Token, false);
Jim Laskey279f0532006-09-25 16:29:54 +00006389 }
Jim Laskeyd1aed7a2006-09-21 16:28:59 +00006390 }
Scott Michelfdc40a02009-02-17 22:15:04 +00006391
Evan Cheng33dbedc2006-11-05 09:31:14 +00006392 // Try transforming N to an indexed store.
Evan Chengbbd6f6e2006-11-07 09:03:05 +00006393 if (CombineToPreIndexedLoadStore(N) || CombineToPostIndexedLoadStore(N))
Dan Gohman475871a2008-07-27 21:46:04 +00006394 return SDValue(N, 0);
Evan Cheng33dbedc2006-11-05 09:31:14 +00006395
Chris Lattner3c872852007-12-29 06:26:16 +00006396 // FIXME: is there such a thing as a truncating indexed store?
Chris Lattnerddf89562008-01-17 19:59:44 +00006397 if (ST->isTruncatingStore() && ST->isUnindexed() &&
Duncan Sands83ec4b62008-06-06 12:08:01 +00006398 Value.getValueType().isInteger()) {
Chris Lattner2b4c2792007-10-13 06:35:54 +00006399 // See if we can simplify the input to this truncstore with knowledge that
6400 // only the low bits are being used. For example:
6401 // "truncstore (or (shl x, 8), y), i8" -> "truncstore y, i8"
Scott Michelfdc40a02009-02-17 22:15:04 +00006402 SDValue Shorter =
Dan Gohman2e68b6f2008-02-25 21:11:39 +00006403 GetDemandedBits(Value,
Bill Wendlingc144a572009-01-30 23:36:47 +00006404 APInt::getLowBitsSet(Value.getValueSizeInBits(),
6405 ST->getMemoryVT().getSizeInBits()));
Gabor Greifba36cb52008-08-28 21:40:38 +00006406 AddToWorkList(Value.getNode());
6407 if (Shorter.getNode())
Bill Wendlingc144a572009-01-30 23:36:47 +00006408 return DAG.getTruncStore(Chain, N->getDebugLoc(), Shorter,
Chris Lattnerda2d8e12010-09-21 17:42:31 +00006409 Ptr, ST->getPointerInfo(), ST->getMemoryVT(),
David Greene1e559442010-02-15 17:00:31 +00006410 ST->isVolatile(), ST->isNonTemporal(),
6411 ST->getAlignment());
Scott Michelfdc40a02009-02-17 22:15:04 +00006412
Chris Lattnere33544c2007-10-13 06:58:48 +00006413 // Otherwise, see if we can simplify the operation with
6414 // SimplifyDemandedBits, which only works if the value has a single use.
Dan Gohman7b8d4a92008-02-27 00:25:32 +00006415 if (SimplifyDemandedBits(Value,
Eric Christopher503a64d2010-12-09 04:48:06 +00006416 APInt::getLowBitsSet(
6417 Value.getValueType().getScalarType().getSizeInBits(),
6418 ST->getMemoryVT().getScalarType().getSizeInBits())))
Dan Gohman475871a2008-07-27 21:46:04 +00006419 return SDValue(N, 0);
Chris Lattner2b4c2792007-10-13 06:35:54 +00006420 }
Scott Michelfdc40a02009-02-17 22:15:04 +00006421
Chris Lattner3c872852007-12-29 06:26:16 +00006422 // If this is a load followed by a store to the same location, then the store
6423 // is dead/noop.
6424 if (LoadSDNode *Ld = dyn_cast<LoadSDNode>(Value)) {
Dan Gohmanb625f2f2008-01-30 00:15:11 +00006425 if (Ld->getBasePtr() == Ptr && ST->getMemoryVT() == Ld->getMemoryVT() &&
Chris Lattnerddf89562008-01-17 19:59:44 +00006426 ST->isUnindexed() && !ST->isVolatile() &&
Chris Lattner07649d92008-01-08 23:08:06 +00006427 // There can't be any side effects between the load and store, such as
6428 // a call or store.
Dan Gohman475871a2008-07-27 21:46:04 +00006429 Chain.reachesChainWithoutSideEffects(SDValue(Ld, 1))) {
Chris Lattner3c872852007-12-29 06:26:16 +00006430 // The store is dead, remove it.
6431 return Chain;
6432 }
6433 }
Duncan Sandsd4b9c172008-06-13 19:07:40 +00006434
Chris Lattnerddf89562008-01-17 19:59:44 +00006435 // If this is an FP_ROUND or TRUNC followed by a store, fold this into a
6436 // truncating store. We can do this even if this is already a truncstore.
6437 if ((Value.getOpcode() == ISD::FP_ROUND || Value.getOpcode() == ISD::TRUNCATE)
Gabor Greifba36cb52008-08-28 21:40:38 +00006438 && Value.getNode()->hasOneUse() && ST->isUnindexed() &&
Chris Lattnerddf89562008-01-17 19:59:44 +00006439 TLI.isTruncStoreLegal(Value.getOperand(0).getValueType(),
Dan Gohmanb625f2f2008-01-30 00:15:11 +00006440 ST->getMemoryVT())) {
Bill Wendlingc144a572009-01-30 23:36:47 +00006441 return DAG.getTruncStore(Chain, N->getDebugLoc(), Value.getOperand(0),
Chris Lattnerda2d8e12010-09-21 17:42:31 +00006442 Ptr, ST->getPointerInfo(), ST->getMemoryVT(),
David Greene1e559442010-02-15 17:00:31 +00006443 ST->isVolatile(), ST->isNonTemporal(),
6444 ST->getAlignment());
Chris Lattnerddf89562008-01-17 19:59:44 +00006445 }
Duncan Sandsd4b9c172008-06-13 19:07:40 +00006446
Evan Cheng8b944d32009-05-28 00:35:15 +00006447 return ReduceLoadOpStoreWidth(N);
Chris Lattner87514ca2005-10-10 22:31:19 +00006448}
6449
Dan Gohman475871a2008-07-27 21:46:04 +00006450SDValue DAGCombiner::visitINSERT_VECTOR_ELT(SDNode *N) {
6451 SDValue InVec = N->getOperand(0);
6452 SDValue InVal = N->getOperand(1);
6453 SDValue EltNo = N->getOperand(2);
Scott Michelfdc40a02009-02-17 22:15:04 +00006454
Bob Wilson492fd452010-05-19 23:42:58 +00006455 // If the inserted element is an UNDEF, just use the input vector.
6456 if (InVal.getOpcode() == ISD::UNDEF)
6457 return InVec;
6458
Nadav Rotem609d54e2011-02-12 14:40:33 +00006459 EVT VT = InVec.getValueType();
6460
Owen Anderson95771af2011-02-25 21:41:48 +00006461 // If we can't generate a legal BUILD_VECTOR, exit
Nadav Rotem609d54e2011-02-12 14:40:33 +00006462 if (LegalOperations && !TLI.isOperationLegal(ISD::BUILD_VECTOR, VT))
6463 return SDValue();
6464
Chris Lattnerca242442006-03-19 01:27:56 +00006465 // If the invec is a BUILD_VECTOR and if EltNo is a constant, build a new
6466 // vector with the inserted element.
6467 if (InVec.getOpcode() == ISD::BUILD_VECTOR && isa<ConstantSDNode>(EltNo)) {
Dan Gohmanf5aeb1a2008-09-12 16:56:44 +00006468 unsigned Elt = cast<ConstantSDNode>(EltNo)->getZExtValue();
Gabor Greif12632d22008-08-30 19:29:20 +00006469 SmallVector<SDValue, 8> Ops(InVec.getNode()->op_begin(),
6470 InVec.getNode()->op_end());
Chris Lattnerca242442006-03-19 01:27:56 +00006471 if (Elt < Ops.size())
6472 Ops[Elt] = InVal;
Evan Chenga87008d2009-02-25 22:49:59 +00006473 return DAG.getNode(ISD::BUILD_VECTOR, N->getDebugLoc(),
Nadav Rotem609d54e2011-02-12 14:40:33 +00006474 VT, &Ops[0], Ops.size());
Chris Lattnerca242442006-03-19 01:27:56 +00006475 }
Wesley Peckbf17cfa2010-11-23 03:31:01 +00006476 // If the invec is an UNDEF and if EltNo is a constant, create a new
Nate Begeman9008ca62009-04-27 18:41:29 +00006477 // BUILD_VECTOR with undef elements and the inserted element.
Nadav Rotem609d54e2011-02-12 14:40:33 +00006478 if (InVec.getOpcode() == ISD::UNDEF &&
Nate Begeman9008ca62009-04-27 18:41:29 +00006479 isa<ConstantSDNode>(EltNo)) {
Dan Gohman8a55ce42009-09-23 21:02:20 +00006480 EVT EltVT = VT.getVectorElementType();
Nate Begeman9008ca62009-04-27 18:41:29 +00006481 unsigned NElts = VT.getVectorNumElements();
Dan Gohman8a55ce42009-09-23 21:02:20 +00006482 SmallVector<SDValue, 8> Ops(NElts, DAG.getUNDEF(EltVT));
Scott Michelfdc40a02009-02-17 22:15:04 +00006483
Nate Begeman9008ca62009-04-27 18:41:29 +00006484 unsigned Elt = cast<ConstantSDNode>(EltNo)->getZExtValue();
6485 if (Elt < Ops.size())
6486 Ops[Elt] = InVal;
6487 return DAG.getNode(ISD::BUILD_VECTOR, N->getDebugLoc(),
Nadav Rotem609d54e2011-02-12 14:40:33 +00006488 VT, &Ops[0], Ops.size());
Nate Begeman9008ca62009-04-27 18:41:29 +00006489 }
Dan Gohman475871a2008-07-27 21:46:04 +00006490 return SDValue();
Chris Lattnerca242442006-03-19 01:27:56 +00006491}
6492
Dan Gohman475871a2008-07-27 21:46:04 +00006493SDValue DAGCombiner::visitEXTRACT_VECTOR_ELT(SDNode *N) {
Mon P Wang7ac9cdf2009-01-17 00:07:25 +00006494 // (vextract (scalar_to_vector val, 0) -> val
6495 SDValue InVec = N->getOperand(0);
Mon P Wang7ac9cdf2009-01-17 00:07:25 +00006496
Duncan Sandsb10b5ac2009-04-18 20:16:54 +00006497 if (InVec.getOpcode() == ISD::SCALAR_TO_VECTOR) {
Mon P Wangc6654ec42010-02-01 19:03:18 +00006498 // Check if the result type doesn't match the inserted element type. A
6499 // SCALAR_TO_VECTOR may truncate the inserted element and the
6500 // EXTRACT_VECTOR_ELT may widen the extracted vector.
Duncan Sandsb10b5ac2009-04-18 20:16:54 +00006501 SDValue InOp = InVec.getOperand(0);
Mon P Wangc6654ec42010-02-01 19:03:18 +00006502 EVT NVT = N->getValueType(0);
6503 if (InOp.getValueType() != NVT) {
6504 assert(InOp.getValueType().isInteger() && NVT.isInteger());
Mon P Wang87c46d82010-02-01 22:15:09 +00006505 return DAG.getSExtOrTrunc(InOp, InVec.getDebugLoc(), NVT);
Mon P Wangc6654ec42010-02-01 19:03:18 +00006506 }
Duncan Sandsb10b5ac2009-04-18 20:16:54 +00006507 return InOp;
6508 }
Evan Cheng77f0b7a2008-05-13 08:35:03 +00006509
6510 // Perform only after legalization to ensure build_vector / vector_shuffle
6511 // optimizations have already been done.
Duncan Sands25cf2272008-11-24 14:53:14 +00006512 if (!LegalOperations) return SDValue();
Evan Cheng77f0b7a2008-05-13 08:35:03 +00006513
Mon P Wang7ac9cdf2009-01-17 00:07:25 +00006514 // (vextract (v4f32 load $addr), c) -> (f32 load $addr+c*size)
6515 // (vextract (v4f32 s2v (f32 load $addr)), c) -> (f32 load $addr+c*size)
6516 // (vextract (v4f32 shuffle (load $addr), <1,u,u,u>), 0) -> (f32 load $addr)
Mon P Wange3bc6ae2009-01-18 06:43:40 +00006517 SDValue EltNo = N->getOperand(1);
Evan Cheng513da432007-10-06 08:19:55 +00006518
Evan Cheng513da432007-10-06 08:19:55 +00006519 if (isa<ConstantSDNode>(EltNo)) {
Eric Christophercaebdd42010-11-03 09:36:40 +00006520 int Elt = cast<ConstantSDNode>(EltNo)->getZExtValue();
Evan Cheng513da432007-10-06 08:19:55 +00006521 bool NewLoad = false;
Mon P Wanga60b5232008-12-11 00:26:16 +00006522 bool BCNumEltsChanged = false;
Owen Andersone50ed302009-08-10 22:56:29 +00006523 EVT VT = InVec.getValueType();
6524 EVT ExtVT = VT.getVectorElementType();
6525 EVT LVT = ExtVT;
Bill Wendlingc144a572009-01-30 23:36:47 +00006526
Wesley Peckbf17cfa2010-11-23 03:31:01 +00006527 if (InVec.getOpcode() == ISD::BITCAST) {
Owen Andersone50ed302009-08-10 22:56:29 +00006528 EVT BCVT = InVec.getOperand(0).getValueType();
6529 if (!BCVT.isVector() || ExtVT.bitsGT(BCVT.getVectorElementType()))
Dan Gohman475871a2008-07-27 21:46:04 +00006530 return SDValue();
Mon P Wanga60b5232008-12-11 00:26:16 +00006531 if (VT.getVectorNumElements() != BCVT.getVectorNumElements())
6532 BCNumEltsChanged = true;
Evan Cheng77f0b7a2008-05-13 08:35:03 +00006533 InVec = InVec.getOperand(0);
Owen Andersone50ed302009-08-10 22:56:29 +00006534 ExtVT = BCVT.getVectorElementType();
Evan Cheng77f0b7a2008-05-13 08:35:03 +00006535 NewLoad = true;
6536 }
Evan Cheng513da432007-10-06 08:19:55 +00006537
Evan Cheng77f0b7a2008-05-13 08:35:03 +00006538 LoadSDNode *LN0 = NULL;
Nate Begeman5a5ca152009-04-29 05:20:52 +00006539 const ShuffleVectorSDNode *SVN = NULL;
Bill Wendlingc144a572009-01-30 23:36:47 +00006540 if (ISD::isNormalLoad(InVec.getNode())) {
Evan Cheng77f0b7a2008-05-13 08:35:03 +00006541 LN0 = cast<LoadSDNode>(InVec);
Bill Wendlingc144a572009-01-30 23:36:47 +00006542 } else if (InVec.getOpcode() == ISD::SCALAR_TO_VECTOR &&
Owen Andersone50ed302009-08-10 22:56:29 +00006543 InVec.getOperand(0).getValueType() == ExtVT &&
Bill Wendlingc144a572009-01-30 23:36:47 +00006544 ISD::isNormalLoad(InVec.getOperand(0).getNode())) {
Evan Cheng77f0b7a2008-05-13 08:35:03 +00006545 LN0 = cast<LoadSDNode>(InVec.getOperand(0));
Nate Begeman5a5ca152009-04-29 05:20:52 +00006546 } else if ((SVN = dyn_cast<ShuffleVectorSDNode>(InVec))) {
Evan Cheng77f0b7a2008-05-13 08:35:03 +00006547 // (vextract (vector_shuffle (load $addr), v2, <1, u, u, u>), 1)
6548 // =>
6549 // (load $addr+1*size)
Scott Michelfdc40a02009-02-17 22:15:04 +00006550
Mon P Wanga60b5232008-12-11 00:26:16 +00006551 // If the bit convert changed the number of elements, it is unsafe
6552 // to examine the mask.
6553 if (BCNumEltsChanged)
6554 return SDValue();
Nate Begeman5a5ca152009-04-29 05:20:52 +00006555
6556 // Select the input vector, guarding against out of range extract vector.
6557 unsigned NumElems = VT.getVectorNumElements();
Eric Christophercaebdd42010-11-03 09:36:40 +00006558 int Idx = (Elt > (int)NumElems) ? -1 : SVN->getMaskElt(Elt);
Nate Begeman5a5ca152009-04-29 05:20:52 +00006559 InVec = (Idx < (int)NumElems) ? InVec.getOperand(0) : InVec.getOperand(1);
6560
Wesley Peckbf17cfa2010-11-23 03:31:01 +00006561 if (InVec.getOpcode() == ISD::BITCAST)
Evan Cheng77f0b7a2008-05-13 08:35:03 +00006562 InVec = InVec.getOperand(0);
Gabor Greifba36cb52008-08-28 21:40:38 +00006563 if (ISD::isNormalLoad(InVec.getNode())) {
Evan Cheng77f0b7a2008-05-13 08:35:03 +00006564 LN0 = cast<LoadSDNode>(InVec);
Ted Kremenekd0e88f32010-04-08 18:49:30 +00006565 Elt = (Idx < (int)NumElems) ? Idx : Idx - (int)NumElems;
Evan Cheng513da432007-10-06 08:19:55 +00006566 }
6567 }
Bill Wendlingc144a572009-01-30 23:36:47 +00006568
Duncan Sandsec87aa82008-06-15 20:12:31 +00006569 if (!LN0 || !LN0->hasOneUse() || LN0->isVolatile())
Dan Gohman475871a2008-07-27 21:46:04 +00006570 return SDValue();
Evan Cheng77f0b7a2008-05-13 08:35:03 +00006571
Eric Christopherd81f17a2010-11-03 20:44:42 +00006572 // If Idx was -1 above, Elt is going to be -1, so just return undef.
6573 if (Elt == -1)
6574 return DAG.getUNDEF(LN0->getBasePtr().getValueType());
6575
Evan Cheng77f0b7a2008-05-13 08:35:03 +00006576 unsigned Align = LN0->getAlignment();
6577 if (NewLoad) {
6578 // Check the resultant load doesn't need a higher alignment than the
6579 // original load.
Bill Wendlingc144a572009-01-30 23:36:47 +00006580 unsigned NewAlign =
Eric Christopher503a64d2010-12-09 04:48:06 +00006581 TLI.getTargetData()
6582 ->getABITypeAlignment(LVT.getTypeForEVT(*DAG.getContext()));
Bill Wendlingc144a572009-01-30 23:36:47 +00006583
Dan Gohmanf560ffa2009-01-28 17:46:25 +00006584 if (NewAlign > Align || !TLI.isOperationLegalOrCustom(ISD::LOAD, LVT))
Dan Gohman475871a2008-07-27 21:46:04 +00006585 return SDValue();
Bill Wendlingc144a572009-01-30 23:36:47 +00006586
Evan Cheng77f0b7a2008-05-13 08:35:03 +00006587 Align = NewAlign;
6588 }
6589
Dan Gohman475871a2008-07-27 21:46:04 +00006590 SDValue NewPtr = LN0->getBasePtr();
Chris Lattnerfa459012010-09-21 16:08:50 +00006591 unsigned PtrOff = 0;
Wesley Peckbf17cfa2010-11-23 03:31:01 +00006592
Eric Christopherd81f17a2010-11-03 20:44:42 +00006593 if (Elt) {
Chris Lattnerfa459012010-09-21 16:08:50 +00006594 PtrOff = LVT.getSizeInBits() * Elt / 8;
Owen Andersone50ed302009-08-10 22:56:29 +00006595 EVT PtrType = NewPtr.getValueType();
Evan Cheng77f0b7a2008-05-13 08:35:03 +00006596 if (TLI.isBigEndian())
Duncan Sands83ec4b62008-06-06 12:08:01 +00006597 PtrOff = VT.getSizeInBits() / 8 - PtrOff;
Bill Wendlingc144a572009-01-30 23:36:47 +00006598 NewPtr = DAG.getNode(ISD::ADD, N->getDebugLoc(), PtrType, NewPtr,
Evan Cheng77f0b7a2008-05-13 08:35:03 +00006599 DAG.getConstant(PtrOff, PtrType));
6600 }
Bill Wendlingc144a572009-01-30 23:36:47 +00006601
6602 return DAG.getLoad(LVT, N->getDebugLoc(), LN0->getChain(), NewPtr,
Chris Lattnerfa459012010-09-21 16:08:50 +00006603 LN0->getPointerInfo().getWithOffset(PtrOff),
David Greene1e559442010-02-15 17:00:31 +00006604 LN0->isVolatile(), LN0->isNonTemporal(), Align);
Evan Cheng513da432007-10-06 08:19:55 +00006605 }
Bill Wendlingc144a572009-01-30 23:36:47 +00006606
Dan Gohman475871a2008-07-27 21:46:04 +00006607 return SDValue();
Evan Cheng513da432007-10-06 08:19:55 +00006608}
Evan Cheng513da432007-10-06 08:19:55 +00006609
Dan Gohman475871a2008-07-27 21:46:04 +00006610SDValue DAGCombiner::visitBUILD_VECTOR(SDNode *N) {
Dan Gohman7f321562007-06-25 16:23:39 +00006611 unsigned NumInScalars = N->getNumOperands();
Owen Andersone50ed302009-08-10 22:56:29 +00006612 EVT VT = N->getValueType(0);
Chris Lattnerca242442006-03-19 01:27:56 +00006613
Dan Gohman7f321562007-06-25 16:23:39 +00006614 // Check to see if this is a BUILD_VECTOR of a bunch of EXTRACT_VECTOR_ELT
6615 // operations. If so, and if the EXTRACT_VECTOR_ELT vector inputs come from
6616 // at most two distinct vectors, turn this into a shuffle node.
Dan Gohman475871a2008-07-27 21:46:04 +00006617 SDValue VecIn1, VecIn2;
Chris Lattnerd7648c82006-03-28 20:28:38 +00006618 for (unsigned i = 0; i != NumInScalars; ++i) {
6619 // Ignore undef inputs.
6620 if (N->getOperand(i).getOpcode() == ISD::UNDEF) continue;
Scott Michelfdc40a02009-02-17 22:15:04 +00006621
Dan Gohman7f321562007-06-25 16:23:39 +00006622 // If this input is something other than a EXTRACT_VECTOR_ELT with a
Chris Lattnerd7648c82006-03-28 20:28:38 +00006623 // constant index, bail out.
Dan Gohman7f321562007-06-25 16:23:39 +00006624 if (N->getOperand(i).getOpcode() != ISD::EXTRACT_VECTOR_ELT ||
Chris Lattnerd7648c82006-03-28 20:28:38 +00006625 !isa<ConstantSDNode>(N->getOperand(i).getOperand(1))) {
Dan Gohman475871a2008-07-27 21:46:04 +00006626 VecIn1 = VecIn2 = SDValue(0, 0);
Chris Lattnerd7648c82006-03-28 20:28:38 +00006627 break;
6628 }
Scott Michelfdc40a02009-02-17 22:15:04 +00006629
Dan Gohman7f321562007-06-25 16:23:39 +00006630 // If the input vector type disagrees with the result of the build_vector,
Chris Lattnerd7648c82006-03-28 20:28:38 +00006631 // we can't make a shuffle.
Dan Gohman475871a2008-07-27 21:46:04 +00006632 SDValue ExtractedFromVec = N->getOperand(i).getOperand(0);
Dan Gohman7f321562007-06-25 16:23:39 +00006633 if (ExtractedFromVec.getValueType() != VT) {
Dan Gohman475871a2008-07-27 21:46:04 +00006634 VecIn1 = VecIn2 = SDValue(0, 0);
Chris Lattnerd7648c82006-03-28 20:28:38 +00006635 break;
6636 }
Scott Michelfdc40a02009-02-17 22:15:04 +00006637
Chris Lattnerd7648c82006-03-28 20:28:38 +00006638 // Otherwise, remember this. We allow up to two distinct input vectors.
6639 if (ExtractedFromVec == VecIn1 || ExtractedFromVec == VecIn2)
6640 continue;
Scott Michelfdc40a02009-02-17 22:15:04 +00006641
Gabor Greifba36cb52008-08-28 21:40:38 +00006642 if (VecIn1.getNode() == 0) {
Chris Lattnerd7648c82006-03-28 20:28:38 +00006643 VecIn1 = ExtractedFromVec;
Gabor Greifba36cb52008-08-28 21:40:38 +00006644 } else if (VecIn2.getNode() == 0) {
Chris Lattnerd7648c82006-03-28 20:28:38 +00006645 VecIn2 = ExtractedFromVec;
6646 } else {
6647 // Too many inputs.
Dan Gohman475871a2008-07-27 21:46:04 +00006648 VecIn1 = VecIn2 = SDValue(0, 0);
Chris Lattnerd7648c82006-03-28 20:28:38 +00006649 break;
6650 }
6651 }
Scott Michelfdc40a02009-02-17 22:15:04 +00006652
Chris Lattnerd7648c82006-03-28 20:28:38 +00006653 // If everything is good, we can make a shuffle operation.
Gabor Greifba36cb52008-08-28 21:40:38 +00006654 if (VecIn1.getNode()) {
Nate Begeman9008ca62009-04-27 18:41:29 +00006655 SmallVector<int, 8> Mask;
Chris Lattnerd7648c82006-03-28 20:28:38 +00006656 for (unsigned i = 0; i != NumInScalars; ++i) {
6657 if (N->getOperand(i).getOpcode() == ISD::UNDEF) {
Nate Begeman9008ca62009-04-27 18:41:29 +00006658 Mask.push_back(-1);
Chris Lattnerd7648c82006-03-28 20:28:38 +00006659 continue;
6660 }
Scott Michelfdc40a02009-02-17 22:15:04 +00006661
Rafael Espindola15684b22009-04-24 12:40:33 +00006662 // If extracting from the first vector, just use the index directly.
Nate Begeman9008ca62009-04-27 18:41:29 +00006663 SDValue Extract = N->getOperand(i);
Mon P Wang93b74152009-03-17 06:33:10 +00006664 SDValue ExtVal = Extract.getOperand(1);
Chris Lattnerd7648c82006-03-28 20:28:38 +00006665 if (Extract.getOperand(0) == VecIn1) {
Nate Begeman5a5ca152009-04-29 05:20:52 +00006666 unsigned ExtIndex = cast<ConstantSDNode>(ExtVal)->getZExtValue();
6667 if (ExtIndex > VT.getVectorNumElements())
6668 return SDValue();
Wesley Peckbf17cfa2010-11-23 03:31:01 +00006669
Nate Begeman5a5ca152009-04-29 05:20:52 +00006670 Mask.push_back(ExtIndex);
Chris Lattnerd7648c82006-03-28 20:28:38 +00006671 continue;
6672 }
6673
6674 // Otherwise, use InIdx + VecSize
Mon P Wang93b74152009-03-17 06:33:10 +00006675 unsigned Idx = cast<ConstantSDNode>(ExtVal)->getZExtValue();
Nate Begeman9008ca62009-04-27 18:41:29 +00006676 Mask.push_back(Idx+NumInScalars);
Chris Lattnerd7648c82006-03-28 20:28:38 +00006677 }
Scott Michelfdc40a02009-02-17 22:15:04 +00006678
Chris Lattnerd7648c82006-03-28 20:28:38 +00006679 // Add count and size info.
Chris Lattner2392ae72010-04-15 04:48:01 +00006680 if (!isTypeLegal(VT))
Duncan Sands25cf2272008-11-24 14:53:14 +00006681 return SDValue();
6682
Dan Gohman7f321562007-06-25 16:23:39 +00006683 // Return the new VECTOR_SHUFFLE node.
Nate Begeman9008ca62009-04-27 18:41:29 +00006684 SDValue Ops[2];
Chris Lattnerbd564bf2006-08-08 02:23:42 +00006685 Ops[0] = VecIn1;
Nate Begeman9008ca62009-04-27 18:41:29 +00006686 Ops[1] = VecIn2.getNode() ? VecIn2 : DAG.getUNDEF(VT);
6687 return DAG.getVectorShuffle(VT, N->getDebugLoc(), Ops[0], Ops[1], &Mask[0]);
Chris Lattnerd7648c82006-03-28 20:28:38 +00006688 }
Scott Michelfdc40a02009-02-17 22:15:04 +00006689
Dan Gohman475871a2008-07-27 21:46:04 +00006690 return SDValue();
Chris Lattnerd7648c82006-03-28 20:28:38 +00006691}
6692
Dan Gohman475871a2008-07-27 21:46:04 +00006693SDValue DAGCombiner::visitCONCAT_VECTORS(SDNode *N) {
Dan Gohman7f321562007-06-25 16:23:39 +00006694 // TODO: Check to see if this is a CONCAT_VECTORS of a bunch of
6695 // EXTRACT_SUBVECTOR operations. If so, and if the EXTRACT_SUBVECTOR vector
6696 // inputs come from at most two distinct vectors, turn this into a shuffle
6697 // node.
6698
6699 // If we only have one input vector, we don't need to do any concatenation.
Bill Wendlingc144a572009-01-30 23:36:47 +00006700 if (N->getNumOperands() == 1)
Dan Gohman7f321562007-06-25 16:23:39 +00006701 return N->getOperand(0);
Dan Gohman7f321562007-06-25 16:23:39 +00006702
Dan Gohman475871a2008-07-27 21:46:04 +00006703 return SDValue();
Dan Gohman7f321562007-06-25 16:23:39 +00006704}
6705
Dan Gohman475871a2008-07-27 21:46:04 +00006706SDValue DAGCombiner::visitVECTOR_SHUFFLE(SDNode *N) {
Owen Andersone50ed302009-08-10 22:56:29 +00006707 EVT VT = N->getValueType(0);
Nate Begeman9008ca62009-04-27 18:41:29 +00006708 unsigned NumElts = VT.getVectorNumElements();
Chris Lattnerf1d0c622006-03-31 22:16:43 +00006709
Mon P Wangaeb06d22008-11-10 04:46:22 +00006710 SDValue N0 = N->getOperand(0);
Mon P Wangaeb06d22008-11-10 04:46:22 +00006711
6712 assert(N0.getValueType().getVectorNumElements() == NumElts &&
6713 "Vector shuffle must be normalized in DAG");
6714
Nate Begeman9008ca62009-04-27 18:41:29 +00006715 // FIXME: implement canonicalizations from DAG.getVectorShuffle()
Evan Chenge7bec0d2006-07-20 22:44:41 +00006716
Bob Wilson0f1db1a2010-10-28 17:06:14 +00006717 // If it is a splat, check if the argument vector is another splat or a
6718 // build_vector with all scalar elements the same.
6719 ShuffleVectorSDNode *SVN = cast<ShuffleVectorSDNode>(N);
6720 if (SVN->isSplat() && SVN->getSplatIndex() < (int)NumElts) {
Gabor Greifba36cb52008-08-28 21:40:38 +00006721 SDNode *V = N0.getNode();
Evan Cheng917ec982006-07-21 08:25:53 +00006722
Dan Gohman7f321562007-06-25 16:23:39 +00006723 // If this is a bit convert that changes the element type of the vector but
Evan Cheng59569222006-10-16 22:49:37 +00006724 // not the number of vector elements, look through it. Be careful not to
6725 // look though conversions that change things like v4f32 to v2f64.
Wesley Peckbf17cfa2010-11-23 03:31:01 +00006726 if (V->getOpcode() == ISD::BITCAST) {
Dan Gohman475871a2008-07-27 21:46:04 +00006727 SDValue ConvInput = V->getOperand(0);
Evan Cheng29257862008-07-22 20:42:56 +00006728 if (ConvInput.getValueType().isVector() &&
6729 ConvInput.getValueType().getVectorNumElements() == NumElts)
Gabor Greifba36cb52008-08-28 21:40:38 +00006730 V = ConvInput.getNode();
Evan Cheng59569222006-10-16 22:49:37 +00006731 }
6732
Dan Gohman7f321562007-06-25 16:23:39 +00006733 if (V->getOpcode() == ISD::BUILD_VECTOR) {
Bob Wilson0f1db1a2010-10-28 17:06:14 +00006734 assert(V->getNumOperands() == NumElts &&
6735 "BUILD_VECTOR has wrong number of operands");
6736 SDValue Base;
6737 bool AllSame = true;
6738 for (unsigned i = 0; i != NumElts; ++i) {
6739 if (V->getOperand(i).getOpcode() != ISD::UNDEF) {
6740 Base = V->getOperand(i);
6741 break;
Evan Cheng917ec982006-07-21 08:25:53 +00006742 }
Evan Cheng917ec982006-07-21 08:25:53 +00006743 }
Bob Wilson0f1db1a2010-10-28 17:06:14 +00006744 // Splat of <u, u, u, u>, return <u, u, u, u>
6745 if (!Base.getNode())
6746 return N0;
6747 for (unsigned i = 0; i != NumElts; ++i) {
6748 if (V->getOperand(i) != Base) {
6749 AllSame = false;
6750 break;
6751 }
6752 }
6753 // Splat of <x, x, x, x>, return <x, x, x, x>
6754 if (AllSame)
6755 return N0;
Evan Cheng917ec982006-07-21 08:25:53 +00006756 }
6757 }
Dan Gohman475871a2008-07-27 21:46:04 +00006758 return SDValue();
Chris Lattnerf1d0c622006-03-31 22:16:43 +00006759}
6760
Jim Grosbach9a526492010-06-23 16:07:42 +00006761SDValue DAGCombiner::visitMEMBARRIER(SDNode* N) {
6762 if (!TLI.getShouldFoldAtomicFences())
6763 return SDValue();
6764
6765 SDValue atomic = N->getOperand(0);
6766 switch (atomic.getOpcode()) {
6767 case ISD::ATOMIC_CMP_SWAP:
6768 case ISD::ATOMIC_SWAP:
6769 case ISD::ATOMIC_LOAD_ADD:
6770 case ISD::ATOMIC_LOAD_SUB:
6771 case ISD::ATOMIC_LOAD_AND:
6772 case ISD::ATOMIC_LOAD_OR:
6773 case ISD::ATOMIC_LOAD_XOR:
6774 case ISD::ATOMIC_LOAD_NAND:
6775 case ISD::ATOMIC_LOAD_MIN:
6776 case ISD::ATOMIC_LOAD_MAX:
6777 case ISD::ATOMIC_LOAD_UMIN:
6778 case ISD::ATOMIC_LOAD_UMAX:
6779 break;
6780 default:
6781 return SDValue();
6782 }
6783
6784 SDValue fence = atomic.getOperand(0);
6785 if (fence.getOpcode() != ISD::MEMBARRIER)
6786 return SDValue();
6787
6788 switch (atomic.getOpcode()) {
6789 case ISD::ATOMIC_CMP_SWAP:
6790 return SDValue(DAG.UpdateNodeOperands(atomic.getNode(),
6791 fence.getOperand(0),
6792 atomic.getOperand(1), atomic.getOperand(2),
6793 atomic.getOperand(3)), atomic.getResNo());
6794 case ISD::ATOMIC_SWAP:
6795 case ISD::ATOMIC_LOAD_ADD:
6796 case ISD::ATOMIC_LOAD_SUB:
6797 case ISD::ATOMIC_LOAD_AND:
6798 case ISD::ATOMIC_LOAD_OR:
6799 case ISD::ATOMIC_LOAD_XOR:
6800 case ISD::ATOMIC_LOAD_NAND:
6801 case ISD::ATOMIC_LOAD_MIN:
6802 case ISD::ATOMIC_LOAD_MAX:
6803 case ISD::ATOMIC_LOAD_UMIN:
6804 case ISD::ATOMIC_LOAD_UMAX:
6805 return SDValue(DAG.UpdateNodeOperands(atomic.getNode(),
6806 fence.getOperand(0),
6807 atomic.getOperand(1), atomic.getOperand(2)),
6808 atomic.getResNo());
6809 default:
6810 return SDValue();
6811 }
6812}
6813
Evan Cheng44f1f092006-04-20 08:56:16 +00006814/// XformToShuffleWithZero - Returns a vector_shuffle if it able to transform
Dan Gohman7f321562007-06-25 16:23:39 +00006815/// an AND to a vector_shuffle with the destination vector and a zero vector.
6816/// e.g. AND V, <0xffffffff, 0, 0xffffffff, 0>. ==>
Evan Cheng44f1f092006-04-20 08:56:16 +00006817/// vector_shuffle V, Zero, <0, 4, 2, 4>
Dan Gohman475871a2008-07-27 21:46:04 +00006818SDValue DAGCombiner::XformToShuffleWithZero(SDNode *N) {
Owen Andersone50ed302009-08-10 22:56:29 +00006819 EVT VT = N->getValueType(0);
Nate Begeman9008ca62009-04-27 18:41:29 +00006820 DebugLoc dl = N->getDebugLoc();
Dan Gohman475871a2008-07-27 21:46:04 +00006821 SDValue LHS = N->getOperand(0);
6822 SDValue RHS = N->getOperand(1);
Dan Gohman7f321562007-06-25 16:23:39 +00006823 if (N->getOpcode() == ISD::AND) {
Wesley Peckbf17cfa2010-11-23 03:31:01 +00006824 if (RHS.getOpcode() == ISD::BITCAST)
Evan Cheng44f1f092006-04-20 08:56:16 +00006825 RHS = RHS.getOperand(0);
Dan Gohman7f321562007-06-25 16:23:39 +00006826 if (RHS.getOpcode() == ISD::BUILD_VECTOR) {
Nate Begeman9008ca62009-04-27 18:41:29 +00006827 SmallVector<int, 8> Indices;
6828 unsigned NumElts = RHS.getNumOperands();
Evan Cheng44f1f092006-04-20 08:56:16 +00006829 for (unsigned i = 0; i != NumElts; ++i) {
Dan Gohman475871a2008-07-27 21:46:04 +00006830 SDValue Elt = RHS.getOperand(i);
Evan Cheng44f1f092006-04-20 08:56:16 +00006831 if (!isa<ConstantSDNode>(Elt))
Dan Gohman475871a2008-07-27 21:46:04 +00006832 return SDValue();
Evan Cheng44f1f092006-04-20 08:56:16 +00006833 else if (cast<ConstantSDNode>(Elt)->isAllOnesValue())
Nate Begeman9008ca62009-04-27 18:41:29 +00006834 Indices.push_back(i);
Evan Cheng44f1f092006-04-20 08:56:16 +00006835 else if (cast<ConstantSDNode>(Elt)->isNullValue())
Nate Begeman9008ca62009-04-27 18:41:29 +00006836 Indices.push_back(NumElts);
Evan Cheng44f1f092006-04-20 08:56:16 +00006837 else
Dan Gohman475871a2008-07-27 21:46:04 +00006838 return SDValue();
Evan Cheng44f1f092006-04-20 08:56:16 +00006839 }
6840
6841 // Let's see if the target supports this vector_shuffle.
Owen Andersone50ed302009-08-10 22:56:29 +00006842 EVT RVT = RHS.getValueType();
Nate Begeman9008ca62009-04-27 18:41:29 +00006843 if (!TLI.isVectorClearMaskLegal(Indices, RVT))
Dan Gohman475871a2008-07-27 21:46:04 +00006844 return SDValue();
Evan Cheng44f1f092006-04-20 08:56:16 +00006845
Dan Gohman7f321562007-06-25 16:23:39 +00006846 // Return the new VECTOR_SHUFFLE node.
Dan Gohman8a55ce42009-09-23 21:02:20 +00006847 EVT EltVT = RVT.getVectorElementType();
Nate Begeman9008ca62009-04-27 18:41:29 +00006848 SmallVector<SDValue,8> ZeroOps(RVT.getVectorNumElements(),
Dan Gohman8a55ce42009-09-23 21:02:20 +00006849 DAG.getConstant(0, EltVT));
Nate Begeman9008ca62009-04-27 18:41:29 +00006850 SDValue Zero = DAG.getNode(ISD::BUILD_VECTOR, N->getDebugLoc(),
6851 RVT, &ZeroOps[0], ZeroOps.size());
Wesley Peckbf17cfa2010-11-23 03:31:01 +00006852 LHS = DAG.getNode(ISD::BITCAST, dl, RVT, LHS);
Nate Begeman9008ca62009-04-27 18:41:29 +00006853 SDValue Shuf = DAG.getVectorShuffle(RVT, dl, LHS, Zero, &Indices[0]);
Wesley Peckbf17cfa2010-11-23 03:31:01 +00006854 return DAG.getNode(ISD::BITCAST, dl, VT, Shuf);
Evan Cheng44f1f092006-04-20 08:56:16 +00006855 }
6856 }
Bill Wendling836ca7d2009-01-30 23:59:18 +00006857
Dan Gohman475871a2008-07-27 21:46:04 +00006858 return SDValue();
Evan Cheng44f1f092006-04-20 08:56:16 +00006859}
6860
Dan Gohman7f321562007-06-25 16:23:39 +00006861/// SimplifyVBinOp - Visit a binary vector operation, like ADD.
Dan Gohman475871a2008-07-27 21:46:04 +00006862SDValue DAGCombiner::SimplifyVBinOp(SDNode *N) {
Dan Gohman7f321562007-06-25 16:23:39 +00006863 // After legalize, the target may be depending on adds and other
6864 // binary ops to provide legal ways to construct constants or other
6865 // things. Simplifying them may result in a loss of legality.
Duncan Sands25cf2272008-11-24 14:53:14 +00006866 if (LegalOperations) return SDValue();
Dan Gohman7f321562007-06-25 16:23:39 +00006867
Bob Wilsond7273432010-12-17 23:06:49 +00006868 assert(N->getValueType(0).isVector() &&
6869 "SimplifyVBinOp only works on vectors!");
Dan Gohman7f321562007-06-25 16:23:39 +00006870
Dan Gohman475871a2008-07-27 21:46:04 +00006871 SDValue LHS = N->getOperand(0);
6872 SDValue RHS = N->getOperand(1);
6873 SDValue Shuffle = XformToShuffleWithZero(N);
Gabor Greifba36cb52008-08-28 21:40:38 +00006874 if (Shuffle.getNode()) return Shuffle;
Evan Cheng44f1f092006-04-20 08:56:16 +00006875
Dan Gohman7f321562007-06-25 16:23:39 +00006876 // If the LHS and RHS are BUILD_VECTOR nodes, see if we can constant fold
Chris Lattneredab1b92006-04-02 03:25:57 +00006877 // this operation.
Scott Michelfdc40a02009-02-17 22:15:04 +00006878 if (LHS.getOpcode() == ISD::BUILD_VECTOR &&
Dan Gohman7f321562007-06-25 16:23:39 +00006879 RHS.getOpcode() == ISD::BUILD_VECTOR) {
Dan Gohman475871a2008-07-27 21:46:04 +00006880 SmallVector<SDValue, 8> Ops;
Dan Gohman7f321562007-06-25 16:23:39 +00006881 for (unsigned i = 0, e = LHS.getNumOperands(); i != e; ++i) {
Dan Gohman475871a2008-07-27 21:46:04 +00006882 SDValue LHSOp = LHS.getOperand(i);
6883 SDValue RHSOp = RHS.getOperand(i);
Chris Lattneredab1b92006-04-02 03:25:57 +00006884 // If these two elements can't be folded, bail out.
6885 if ((LHSOp.getOpcode() != ISD::UNDEF &&
6886 LHSOp.getOpcode() != ISD::Constant &&
6887 LHSOp.getOpcode() != ISD::ConstantFP) ||
6888 (RHSOp.getOpcode() != ISD::UNDEF &&
6889 RHSOp.getOpcode() != ISD::Constant &&
6890 RHSOp.getOpcode() != ISD::ConstantFP))
6891 break;
Bill Wendling836ca7d2009-01-30 23:59:18 +00006892
Evan Cheng7b336a82006-05-31 06:08:35 +00006893 // Can't fold divide by zero.
Dan Gohman7f321562007-06-25 16:23:39 +00006894 if (N->getOpcode() == ISD::SDIV || N->getOpcode() == ISD::UDIV ||
6895 N->getOpcode() == ISD::FDIV) {
Evan Cheng7b336a82006-05-31 06:08:35 +00006896 if ((RHSOp.getOpcode() == ISD::Constant &&
Gabor Greifba36cb52008-08-28 21:40:38 +00006897 cast<ConstantSDNode>(RHSOp.getNode())->isNullValue()) ||
Evan Cheng7b336a82006-05-31 06:08:35 +00006898 (RHSOp.getOpcode() == ISD::ConstantFP &&
Gabor Greifba36cb52008-08-28 21:40:38 +00006899 cast<ConstantFPSDNode>(RHSOp.getNode())->getValueAPF().isZero()))
Evan Cheng7b336a82006-05-31 06:08:35 +00006900 break;
6901 }
Bill Wendling836ca7d2009-01-30 23:59:18 +00006902
Bob Wilsond7273432010-12-17 23:06:49 +00006903 EVT VT = LHSOp.getValueType();
6904 assert(RHSOp.getValueType() == VT &&
6905 "SimplifyVBinOp with different BUILD_VECTOR element types");
6906 SDValue FoldOp = DAG.getNode(N->getOpcode(), LHS.getDebugLoc(), VT,
Evan Chenga0839882010-05-18 00:03:40 +00006907 LHSOp, RHSOp);
6908 if (FoldOp.getOpcode() != ISD::UNDEF &&
6909 FoldOp.getOpcode() != ISD::Constant &&
6910 FoldOp.getOpcode() != ISD::ConstantFP)
6911 break;
6912 Ops.push_back(FoldOp);
6913 AddToWorkList(FoldOp.getNode());
Chris Lattneredab1b92006-04-02 03:25:57 +00006914 }
Scott Michelfdc40a02009-02-17 22:15:04 +00006915
Bob Wilsond7273432010-12-17 23:06:49 +00006916 if (Ops.size() == LHS.getNumOperands())
6917 return DAG.getNode(ISD::BUILD_VECTOR, N->getDebugLoc(),
6918 LHS.getValueType(), &Ops[0], Ops.size());
Chris Lattneredab1b92006-04-02 03:25:57 +00006919 }
Scott Michelfdc40a02009-02-17 22:15:04 +00006920
Dan Gohman475871a2008-07-27 21:46:04 +00006921 return SDValue();
Chris Lattneredab1b92006-04-02 03:25:57 +00006922}
6923
Bill Wendling836ca7d2009-01-30 23:59:18 +00006924SDValue DAGCombiner::SimplifySelect(DebugLoc DL, SDValue N0,
6925 SDValue N1, SDValue N2){
Nate Begemanf845b452005-10-08 00:29:44 +00006926 assert(N0.getOpcode() ==ISD::SETCC && "First argument must be a SetCC node!");
Scott Michelfdc40a02009-02-17 22:15:04 +00006927
Bill Wendling836ca7d2009-01-30 23:59:18 +00006928 SDValue SCC = SimplifySelectCC(DL, N0.getOperand(0), N0.getOperand(1), N1, N2,
Nate Begemanf845b452005-10-08 00:29:44 +00006929 cast<CondCodeSDNode>(N0.getOperand(2))->get());
Bill Wendling836ca7d2009-01-30 23:59:18 +00006930
Nate Begemanf845b452005-10-08 00:29:44 +00006931 // If we got a simplified select_cc node back from SimplifySelectCC, then
6932 // break it down into a new SETCC node, and a new SELECT node, and then return
6933 // the SELECT node, since we were called with a SELECT node.
Gabor Greifba36cb52008-08-28 21:40:38 +00006934 if (SCC.getNode()) {
Nate Begemanf845b452005-10-08 00:29:44 +00006935 // Check to see if we got a select_cc back (to turn into setcc/select).
6936 // Otherwise, just return whatever node we got back, like fabs.
6937 if (SCC.getOpcode() == ISD::SELECT_CC) {
Bill Wendling836ca7d2009-01-30 23:59:18 +00006938 SDValue SETCC = DAG.getNode(ISD::SETCC, N0.getDebugLoc(),
6939 N0.getValueType(),
Scott Michelfdc40a02009-02-17 22:15:04 +00006940 SCC.getOperand(0), SCC.getOperand(1),
Bill Wendling836ca7d2009-01-30 23:59:18 +00006941 SCC.getOperand(4));
Gabor Greifba36cb52008-08-28 21:40:38 +00006942 AddToWorkList(SETCC.getNode());
Bill Wendling836ca7d2009-01-30 23:59:18 +00006943 return DAG.getNode(ISD::SELECT, SCC.getDebugLoc(), SCC.getValueType(),
6944 SCC.getOperand(2), SCC.getOperand(3), SETCC);
Nate Begemanf845b452005-10-08 00:29:44 +00006945 }
Bill Wendling836ca7d2009-01-30 23:59:18 +00006946
Nate Begemanf845b452005-10-08 00:29:44 +00006947 return SCC;
6948 }
Dan Gohman475871a2008-07-27 21:46:04 +00006949 return SDValue();
Nate Begeman44728a72005-09-19 22:34:01 +00006950}
6951
Chris Lattner40c62d52005-10-18 06:04:22 +00006952/// SimplifySelectOps - Given a SELECT or a SELECT_CC node, where LHS and RHS
6953/// are the two values being selected between, see if we can simplify the
Chris Lattner729c6d12006-05-27 00:43:02 +00006954/// select. Callers of this should assume that TheSelect is deleted if this
6955/// returns true. As such, they should return the appropriate thing (e.g. the
6956/// node) back to the top-level of the DAG combiner loop to avoid it being
6957/// looked at.
Scott Michelfdc40a02009-02-17 22:15:04 +00006958bool DAGCombiner::SimplifySelectOps(SDNode *TheSelect, SDValue LHS,
Dan Gohman475871a2008-07-27 21:46:04 +00006959 SDValue RHS) {
Scott Michelfdc40a02009-02-17 22:15:04 +00006960
Nadav Rotemf94fdb62011-02-11 19:57:47 +00006961 // Cannot simplify select with vector condition
6962 if (TheSelect->getOperand(0).getValueType().isVector()) return false;
6963
Chris Lattner40c62d52005-10-18 06:04:22 +00006964 // If this is a select from two identical things, try to pull the operation
6965 // through the select.
Chris Lattner18061612010-09-21 15:46:59 +00006966 if (LHS.getOpcode() != RHS.getOpcode() ||
6967 !LHS.hasOneUse() || !RHS.hasOneUse())
6968 return false;
Wesley Peckbf17cfa2010-11-23 03:31:01 +00006969
Chris Lattner18061612010-09-21 15:46:59 +00006970 // If this is a load and the token chain is identical, replace the select
6971 // of two loads with a load through a select of the address to load from.
6972 // This triggers in things like "select bool X, 10.0, 123.0" after the FP
6973 // constants have been dropped into the constant pool.
6974 if (LHS.getOpcode() == ISD::LOAD) {
6975 LoadSDNode *LLD = cast<LoadSDNode>(LHS);
6976 LoadSDNode *RLD = cast<LoadSDNode>(RHS);
Wesley Peckbf17cfa2010-11-23 03:31:01 +00006977
Chris Lattner18061612010-09-21 15:46:59 +00006978 // Token chains must be identical.
6979 if (LHS.getOperand(0) != RHS.getOperand(0) ||
Duncan Sandsd4b9c172008-06-13 19:07:40 +00006980 // Do not let this transformation reduce the number of volatile loads.
Chris Lattner18061612010-09-21 15:46:59 +00006981 LLD->isVolatile() || RLD->isVolatile() ||
6982 // If this is an EXTLOAD, the VT's must match.
6983 LLD->getMemoryVT() != RLD->getMemoryVT() ||
Duncan Sandsdcfd3a72010-11-18 20:05:18 +00006984 // If this is an EXTLOAD, the kind of extension must match.
6985 (LLD->getExtensionType() != RLD->getExtensionType() &&
6986 // The only exception is if one of the extensions is anyext.
6987 LLD->getExtensionType() != ISD::EXTLOAD &&
6988 RLD->getExtensionType() != ISD::EXTLOAD) ||
Dan Gohman75832d72009-10-31 14:14:04 +00006989 // FIXME: this discards src value information. This is
6990 // over-conservative. It would be beneficial to be able to remember
Mon P Wangfe240b12010-01-11 20:12:49 +00006991 // both potential memory locations. Since we are discarding
6992 // src value info, don't do the transformation if the memory
6993 // locations are not in the default address space.
Chris Lattner18061612010-09-21 15:46:59 +00006994 LLD->getPointerInfo().getAddrSpace() != 0 ||
6995 RLD->getPointerInfo().getAddrSpace() != 0)
6996 return false;
Wesley Peckbf17cfa2010-11-23 03:31:01 +00006997
Chris Lattnerf1658062010-09-21 15:58:55 +00006998 // Check that the select condition doesn't reach either load. If so,
6999 // folding this will induce a cycle into the DAG. If not, this is safe to
7000 // xform, so create a select of the addresses.
Chris Lattner18061612010-09-21 15:46:59 +00007001 SDValue Addr;
7002 if (TheSelect->getOpcode() == ISD::SELECT) {
Chris Lattnerf1658062010-09-21 15:58:55 +00007003 SDNode *CondNode = TheSelect->getOperand(0).getNode();
7004 if ((LLD->hasAnyUseOfValue(1) && LLD->isPredecessorOf(CondNode)) ||
7005 (RLD->hasAnyUseOfValue(1) && RLD->isPredecessorOf(CondNode)))
7006 return false;
7007 Addr = DAG.getNode(ISD::SELECT, TheSelect->getDebugLoc(),
7008 LLD->getBasePtr().getValueType(),
7009 TheSelect->getOperand(0), LLD->getBasePtr(),
7010 RLD->getBasePtr());
Chris Lattner18061612010-09-21 15:46:59 +00007011 } else { // Otherwise SELECT_CC
Chris Lattnerf1658062010-09-21 15:58:55 +00007012 SDNode *CondLHS = TheSelect->getOperand(0).getNode();
7013 SDNode *CondRHS = TheSelect->getOperand(1).getNode();
7014
7015 if ((LLD->hasAnyUseOfValue(1) &&
7016 (LLD->isPredecessorOf(CondLHS) || LLD->isPredecessorOf(CondRHS))) ||
7017 (LLD->hasAnyUseOfValue(1) &&
7018 (LLD->isPredecessorOf(CondLHS) || LLD->isPredecessorOf(CondRHS))))
7019 return false;
Wesley Peckbf17cfa2010-11-23 03:31:01 +00007020
Chris Lattnerf1658062010-09-21 15:58:55 +00007021 Addr = DAG.getNode(ISD::SELECT_CC, TheSelect->getDebugLoc(),
7022 LLD->getBasePtr().getValueType(),
7023 TheSelect->getOperand(0),
7024 TheSelect->getOperand(1),
7025 LLD->getBasePtr(), RLD->getBasePtr(),
7026 TheSelect->getOperand(4));
Chris Lattner18061612010-09-21 15:46:59 +00007027 }
7028
Chris Lattnerf1658062010-09-21 15:58:55 +00007029 SDValue Load;
7030 if (LLD->getExtensionType() == ISD::NON_EXTLOAD) {
7031 Load = DAG.getLoad(TheSelect->getValueType(0),
7032 TheSelect->getDebugLoc(),
7033 // FIXME: Discards pointer info.
7034 LLD->getChain(), Addr, MachinePointerInfo(),
7035 LLD->isVolatile(), LLD->isNonTemporal(),
7036 LLD->getAlignment());
7037 } else {
Duncan Sandsb9064bb2010-11-18 21:16:28 +00007038 Load = DAG.getExtLoad(LLD->getExtensionType() == ISD::EXTLOAD ?
7039 RLD->getExtensionType() : LLD->getExtensionType(),
Chris Lattnerf1658062010-09-21 15:58:55 +00007040 TheSelect->getDebugLoc(),
Stuart Hastingsa9011292011-02-16 16:23:55 +00007041 TheSelect->getValueType(0),
Chris Lattnerf1658062010-09-21 15:58:55 +00007042 // FIXME: Discards pointer info.
7043 LLD->getChain(), Addr, MachinePointerInfo(),
7044 LLD->getMemoryVT(), LLD->isVolatile(),
7045 LLD->isNonTemporal(), LLD->getAlignment());
Chris Lattner40c62d52005-10-18 06:04:22 +00007046 }
Chris Lattnerf1658062010-09-21 15:58:55 +00007047
7048 // Users of the select now use the result of the load.
7049 CombineTo(TheSelect, Load);
7050
7051 // Users of the old loads now use the new load's chain. We know the
7052 // old-load value is dead now.
7053 CombineTo(LHS.getNode(), Load.getValue(0), Load.getValue(1));
7054 CombineTo(RHS.getNode(), Load.getValue(0), Load.getValue(1));
7055 return true;
Chris Lattner40c62d52005-10-18 06:04:22 +00007056 }
Scott Michelfdc40a02009-02-17 22:15:04 +00007057
Chris Lattner40c62d52005-10-18 06:04:22 +00007058 return false;
7059}
7060
Chris Lattner600fec32009-03-11 05:08:08 +00007061/// SimplifySelectCC - Simplify an expression of the form (N0 cond N1) ? N2 : N3
7062/// where 'cond' is the comparison specified by CC.
Scott Michelfdc40a02009-02-17 22:15:04 +00007063SDValue DAGCombiner::SimplifySelectCC(DebugLoc DL, SDValue N0, SDValue N1,
Dan Gohman475871a2008-07-27 21:46:04 +00007064 SDValue N2, SDValue N3,
7065 ISD::CondCode CC, bool NotExtCompare) {
Chris Lattner600fec32009-03-11 05:08:08 +00007066 // (x ? y : y) -> y.
7067 if (N2 == N3) return N2;
Wesley Peckbf17cfa2010-11-23 03:31:01 +00007068
Owen Andersone50ed302009-08-10 22:56:29 +00007069 EVT VT = N2.getValueType();
Gabor Greifba36cb52008-08-28 21:40:38 +00007070 ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1.getNode());
7071 ConstantSDNode *N2C = dyn_cast<ConstantSDNode>(N2.getNode());
7072 ConstantSDNode *N3C = dyn_cast<ConstantSDNode>(N3.getNode());
Nate Begemanf845b452005-10-08 00:29:44 +00007073
7074 // Determine if the condition we're dealing with is constant
Duncan Sands5480c042009-01-01 15:52:00 +00007075 SDValue SCC = SimplifySetCC(TLI.getSetCCResultType(N0.getValueType()),
Dale Johannesenff97d4f2009-02-03 00:47:48 +00007076 N0, N1, CC, DL, false);
Gabor Greifba36cb52008-08-28 21:40:38 +00007077 if (SCC.getNode()) AddToWorkList(SCC.getNode());
7078 ConstantSDNode *SCCC = dyn_cast_or_null<ConstantSDNode>(SCC.getNode());
Nate Begemanf845b452005-10-08 00:29:44 +00007079
7080 // fold select_cc true, x, y -> x
Dan Gohman002e5d02008-03-13 22:13:53 +00007081 if (SCCC && !SCCC->isNullValue())
Nate Begemanf845b452005-10-08 00:29:44 +00007082 return N2;
7083 // fold select_cc false, x, y -> y
Dan Gohman002e5d02008-03-13 22:13:53 +00007084 if (SCCC && SCCC->isNullValue())
Nate Begemanf845b452005-10-08 00:29:44 +00007085 return N3;
Scott Michelfdc40a02009-02-17 22:15:04 +00007086
Nate Begemanf845b452005-10-08 00:29:44 +00007087 // Check to see if we can simplify the select into an fabs node
7088 if (ConstantFPSDNode *CFP = dyn_cast<ConstantFPSDNode>(N1)) {
7089 // Allow either -0.0 or 0.0
Dale Johannesen87503a62007-08-25 22:10:57 +00007090 if (CFP->getValueAPF().isZero()) {
Nate Begemanf845b452005-10-08 00:29:44 +00007091 // select (setg[te] X, +/-0.0), X, fneg(X) -> fabs
7092 if ((CC == ISD::SETGE || CC == ISD::SETGT) &&
7093 N0 == N2 && N3.getOpcode() == ISD::FNEG &&
7094 N2 == N3.getOperand(0))
Bill Wendling836ca7d2009-01-30 23:59:18 +00007095 return DAG.getNode(ISD::FABS, DL, VT, N0);
Scott Michelfdc40a02009-02-17 22:15:04 +00007096
Nate Begemanf845b452005-10-08 00:29:44 +00007097 // select (setl[te] X, +/-0.0), fneg(X), X -> fabs
7098 if ((CC == ISD::SETLT || CC == ISD::SETLE) &&
7099 N0 == N3 && N2.getOpcode() == ISD::FNEG &&
7100 N2.getOperand(0) == N3)
Bill Wendling836ca7d2009-01-30 23:59:18 +00007101 return DAG.getNode(ISD::FABS, DL, VT, N3);
Nate Begemanf845b452005-10-08 00:29:44 +00007102 }
7103 }
Wesley Peckbf17cfa2010-11-23 03:31:01 +00007104
Chris Lattner600fec32009-03-11 05:08:08 +00007105 // Turn "(a cond b) ? 1.0f : 2.0f" into "load (tmp + ((a cond b) ? 0 : 4)"
7106 // where "tmp" is a constant pool entry containing an array with 1.0 and 2.0
7107 // in it. This is a win when the constant is not otherwise available because
7108 // it replaces two constant pool loads with one. We only do this if the FP
7109 // type is known to be legal, because if it isn't, then we are before legalize
7110 // types an we want the other legalization to happen first (e.g. to avoid
Mon P Wang0b7a7862009-03-14 00:25:19 +00007111 // messing with soft float) and if the ConstantFP is not legal, because if
7112 // it is legal, we may not need to store the FP constant in a constant pool.
Chris Lattner600fec32009-03-11 05:08:08 +00007113 if (ConstantFPSDNode *TV = dyn_cast<ConstantFPSDNode>(N2))
7114 if (ConstantFPSDNode *FV = dyn_cast<ConstantFPSDNode>(N3)) {
7115 if (TLI.isTypeLegal(N2.getValueType()) &&
Mon P Wang0b7a7862009-03-14 00:25:19 +00007116 (TLI.getOperationAction(ISD::ConstantFP, N2.getValueType()) !=
7117 TargetLowering::Legal) &&
Chris Lattner600fec32009-03-11 05:08:08 +00007118 // If both constants have multiple uses, then we won't need to do an
7119 // extra load, they are likely around in registers for other users.
7120 (TV->hasOneUse() || FV->hasOneUse())) {
7121 Constant *Elts[] = {
7122 const_cast<ConstantFP*>(FV->getConstantFPValue()),
7123 const_cast<ConstantFP*>(TV->getConstantFPValue())
7124 };
7125 const Type *FPTy = Elts[0]->getType();
7126 const TargetData &TD = *TLI.getTargetData();
Wesley Peckbf17cfa2010-11-23 03:31:01 +00007127
Chris Lattner600fec32009-03-11 05:08:08 +00007128 // Create a ConstantArray of the two constants.
Owen Andersondebcb012009-07-29 22:17:13 +00007129 Constant *CA = ConstantArray::get(ArrayType::get(FPTy, 2), Elts, 2);
Chris Lattner600fec32009-03-11 05:08:08 +00007130 SDValue CPIdx = DAG.getConstantPool(CA, TLI.getPointerTy(),
7131 TD.getPrefTypeAlignment(FPTy));
Evan Cheng1606e8e2009-03-13 07:51:59 +00007132 unsigned Alignment = cast<ConstantPoolSDNode>(CPIdx)->getAlignment();
Chris Lattner600fec32009-03-11 05:08:08 +00007133
7134 // Get the offsets to the 0 and 1 element of the array so that we can
7135 // select between them.
7136 SDValue Zero = DAG.getIntPtrConstant(0);
Duncan Sands777d2302009-05-09 07:06:46 +00007137 unsigned EltSize = (unsigned)TD.getTypeAllocSize(Elts[0]->getType());
Chris Lattner600fec32009-03-11 05:08:08 +00007138 SDValue One = DAG.getIntPtrConstant(EltSize);
Wesley Peckbf17cfa2010-11-23 03:31:01 +00007139
Chris Lattner600fec32009-03-11 05:08:08 +00007140 SDValue Cond = DAG.getSetCC(DL,
7141 TLI.getSetCCResultType(N0.getValueType()),
7142 N0, N1, CC);
7143 SDValue CstOffset = DAG.getNode(ISD::SELECT, DL, Zero.getValueType(),
7144 Cond, One, Zero);
7145 CPIdx = DAG.getNode(ISD::ADD, DL, TLI.getPointerTy(), CPIdx,
7146 CstOffset);
7147 return DAG.getLoad(TV->getValueType(0), DL, DAG.getEntryNode(), CPIdx,
Chris Lattner85ca1062010-09-21 07:32:19 +00007148 MachinePointerInfo::getConstantPool(), false,
David Greene1e559442010-02-15 17:00:31 +00007149 false, Alignment);
Chris Lattner600fec32009-03-11 05:08:08 +00007150
7151 }
Wesley Peckbf17cfa2010-11-23 03:31:01 +00007152 }
Scott Michelfdc40a02009-02-17 22:15:04 +00007153
Nate Begemanf845b452005-10-08 00:29:44 +00007154 // Check to see if we can perform the "gzip trick", transforming
Bill Wendling836ca7d2009-01-30 23:59:18 +00007155 // (select_cc setlt X, 0, A, 0) -> (and (sra X, (sub size(X), 1), A)
Chris Lattnere3152e52006-09-20 06:41:35 +00007156 if (N1C && N3C && N3C->isNullValue() && CC == ISD::SETLT &&
Duncan Sands83ec4b62008-06-06 12:08:01 +00007157 N0.getValueType().isInteger() &&
7158 N2.getValueType().isInteger() &&
Dan Gohman002e5d02008-03-13 22:13:53 +00007159 (N1C->isNullValue() || // (a < 0) ? b : 0
7160 (N1C->getAPIntValue() == 1 && N0 == N2))) { // (a < 1) ? a : 0
Owen Andersone50ed302009-08-10 22:56:29 +00007161 EVT XType = N0.getValueType();
7162 EVT AType = N2.getValueType();
Duncan Sands8e4eb092008-06-08 20:54:56 +00007163 if (XType.bitsGE(AType)) {
Nate Begemanf845b452005-10-08 00:29:44 +00007164 // and (sra X, size(X)-1, A) -> "and (srl X, C2), A" iff A is a
Nate Begeman07ed4172005-10-10 21:26:48 +00007165 // single-bit constant.
Dan Gohman002e5d02008-03-13 22:13:53 +00007166 if (N2C && ((N2C->getAPIntValue() & (N2C->getAPIntValue()-1)) == 0)) {
7167 unsigned ShCtV = N2C->getAPIntValue().logBase2();
Duncan Sands83ec4b62008-06-06 12:08:01 +00007168 ShCtV = XType.getSizeInBits()-ShCtV-1;
Owen Anderson95771af2011-02-25 21:41:48 +00007169 SDValue ShCt = DAG.getConstant(ShCtV,
7170 getShiftAmountTy(N0.getValueType()));
Bill Wendling9729c5a2009-01-31 03:12:48 +00007171 SDValue Shift = DAG.getNode(ISD::SRL, N0.getDebugLoc(),
Bill Wendling836ca7d2009-01-30 23:59:18 +00007172 XType, N0, ShCt);
Gabor Greifba36cb52008-08-28 21:40:38 +00007173 AddToWorkList(Shift.getNode());
Bill Wendling836ca7d2009-01-30 23:59:18 +00007174
Duncan Sands8e4eb092008-06-08 20:54:56 +00007175 if (XType.bitsGT(AType)) {
Bill Wendling9729c5a2009-01-31 03:12:48 +00007176 Shift = DAG.getNode(ISD::TRUNCATE, DL, AType, Shift);
Gabor Greifba36cb52008-08-28 21:40:38 +00007177 AddToWorkList(Shift.getNode());
Nate Begemanf845b452005-10-08 00:29:44 +00007178 }
Bill Wendling836ca7d2009-01-30 23:59:18 +00007179
7180 return DAG.getNode(ISD::AND, DL, AType, Shift, N2);
Nate Begemanf845b452005-10-08 00:29:44 +00007181 }
Bill Wendling836ca7d2009-01-30 23:59:18 +00007182
Bill Wendling9729c5a2009-01-31 03:12:48 +00007183 SDValue Shift = DAG.getNode(ISD::SRA, N0.getDebugLoc(),
Bill Wendling836ca7d2009-01-30 23:59:18 +00007184 XType, N0,
7185 DAG.getConstant(XType.getSizeInBits()-1,
Owen Anderson95771af2011-02-25 21:41:48 +00007186 getShiftAmountTy(N0.getValueType())));
Gabor Greifba36cb52008-08-28 21:40:38 +00007187 AddToWorkList(Shift.getNode());
Bill Wendling836ca7d2009-01-30 23:59:18 +00007188
Duncan Sands8e4eb092008-06-08 20:54:56 +00007189 if (XType.bitsGT(AType)) {
Bill Wendling9729c5a2009-01-31 03:12:48 +00007190 Shift = DAG.getNode(ISD::TRUNCATE, DL, AType, Shift);
Gabor Greifba36cb52008-08-28 21:40:38 +00007191 AddToWorkList(Shift.getNode());
Nate Begemanf845b452005-10-08 00:29:44 +00007192 }
Bill Wendling836ca7d2009-01-30 23:59:18 +00007193
7194 return DAG.getNode(ISD::AND, DL, AType, Shift, N2);
Nate Begemanf845b452005-10-08 00:29:44 +00007195 }
7196 }
Scott Michelfdc40a02009-02-17 22:15:04 +00007197
Owen Andersoned1088a2010-09-22 22:58:22 +00007198 // fold (select_cc seteq (and x, y), 0, 0, A) -> (and (shr (shl x)) A)
7199 // where y is has a single bit set.
7200 // A plaintext description would be, we can turn the SELECT_CC into an AND
7201 // when the condition can be materialized as an all-ones register. Any
7202 // single bit-test can be materialized as an all-ones register with
7203 // shift-left and shift-right-arith.
7204 if (CC == ISD::SETEQ && N0->getOpcode() == ISD::AND &&
7205 N0->getValueType(0) == VT &&
Wesley Peckbf17cfa2010-11-23 03:31:01 +00007206 N1C && N1C->isNullValue() &&
Owen Andersoned1088a2010-09-22 22:58:22 +00007207 N2C && N2C->isNullValue()) {
7208 SDValue AndLHS = N0->getOperand(0);
7209 ConstantSDNode *ConstAndRHS = dyn_cast<ConstantSDNode>(N0->getOperand(1));
7210 if (ConstAndRHS && ConstAndRHS->getAPIntValue().countPopulation() == 1) {
7211 // Shift the tested bit over the sign bit.
7212 APInt AndMask = ConstAndRHS->getAPIntValue();
7213 SDValue ShlAmt =
Owen Anderson95771af2011-02-25 21:41:48 +00007214 DAG.getConstant(AndMask.countLeadingZeros(),
7215 getShiftAmountTy(AndLHS.getValueType()));
Owen Andersoned1088a2010-09-22 22:58:22 +00007216 SDValue Shl = DAG.getNode(ISD::SHL, N0.getDebugLoc(), VT, AndLHS, ShlAmt);
Wesley Peckbf17cfa2010-11-23 03:31:01 +00007217
Owen Andersoned1088a2010-09-22 22:58:22 +00007218 // Now arithmetic right shift it all the way over, so the result is either
7219 // all-ones, or zero.
7220 SDValue ShrAmt =
Owen Anderson95771af2011-02-25 21:41:48 +00007221 DAG.getConstant(AndMask.getBitWidth()-1,
7222 getShiftAmountTy(Shl.getValueType()));
Owen Andersoned1088a2010-09-22 22:58:22 +00007223 SDValue Shr = DAG.getNode(ISD::SRA, N0.getDebugLoc(), VT, Shl, ShrAmt);
Wesley Peckbf17cfa2010-11-23 03:31:01 +00007224
Owen Andersoned1088a2010-09-22 22:58:22 +00007225 return DAG.getNode(ISD::AND, DL, VT, Shr, N3);
7226 }
7227 }
7228
Nate Begeman07ed4172005-10-10 21:26:48 +00007229 // fold select C, 16, 0 -> shl C, 4
Dan Gohman002e5d02008-03-13 22:13:53 +00007230 if (N2C && N3C && N3C->isNullValue() && N2C->getAPIntValue().isPowerOf2() &&
Duncan Sands03228082008-11-23 15:47:28 +00007231 TLI.getBooleanContents() == TargetLowering::ZeroOrOneBooleanContent) {
Scott Michelfdc40a02009-02-17 22:15:04 +00007232
Chris Lattner1eba01e2007-04-11 06:50:51 +00007233 // If the caller doesn't want us to simplify this into a zext of a compare,
7234 // don't do it.
Dan Gohman002e5d02008-03-13 22:13:53 +00007235 if (NotExtCompare && N2C->getAPIntValue() == 1)
Dan Gohman475871a2008-07-27 21:46:04 +00007236 return SDValue();
Scott Michelfdc40a02009-02-17 22:15:04 +00007237
Nate Begeman07ed4172005-10-10 21:26:48 +00007238 // Get a SetCC of the condition
7239 // FIXME: Should probably make sure that setcc is legal if we ever have a
7240 // target where it isn't.
Dan Gohman475871a2008-07-27 21:46:04 +00007241 SDValue Temp, SCC;
Nate Begeman07ed4172005-10-10 21:26:48 +00007242 // cast from setcc result type to select result type
Duncan Sands25cf2272008-11-24 14:53:14 +00007243 if (LegalTypes) {
Bill Wendling9729c5a2009-01-31 03:12:48 +00007244 SCC = DAG.getSetCC(DL, TLI.getSetCCResultType(N0.getValueType()),
Duncan Sands5480c042009-01-01 15:52:00 +00007245 N0, N1, CC);
Duncan Sands8e4eb092008-06-08 20:54:56 +00007246 if (N2.getValueType().bitsLT(SCC.getValueType()))
Bill Wendling9729c5a2009-01-31 03:12:48 +00007247 Temp = DAG.getZeroExtendInReg(SCC, N2.getDebugLoc(), N2.getValueType());
Chris Lattner555d8d62006-12-07 22:36:47 +00007248 else
Bill Wendling9729c5a2009-01-31 03:12:48 +00007249 Temp = DAG.getNode(ISD::ZERO_EXTEND, N2.getDebugLoc(),
Bill Wendling836ca7d2009-01-30 23:59:18 +00007250 N2.getValueType(), SCC);
Nate Begemanb0d04a72006-02-18 02:40:58 +00007251 } else {
Owen Anderson825b72b2009-08-11 20:47:22 +00007252 SCC = DAG.getSetCC(N0.getDebugLoc(), MVT::i1, N0, N1, CC);
Bill Wendling9729c5a2009-01-31 03:12:48 +00007253 Temp = DAG.getNode(ISD::ZERO_EXTEND, N2.getDebugLoc(),
Bill Wendling836ca7d2009-01-30 23:59:18 +00007254 N2.getValueType(), SCC);
Nate Begemanb0d04a72006-02-18 02:40:58 +00007255 }
Bill Wendling836ca7d2009-01-30 23:59:18 +00007256
Gabor Greifba36cb52008-08-28 21:40:38 +00007257 AddToWorkList(SCC.getNode());
7258 AddToWorkList(Temp.getNode());
Scott Michelfdc40a02009-02-17 22:15:04 +00007259
Dan Gohman002e5d02008-03-13 22:13:53 +00007260 if (N2C->getAPIntValue() == 1)
Chris Lattnerc56a81d2007-04-11 06:43:25 +00007261 return Temp;
Bill Wendling836ca7d2009-01-30 23:59:18 +00007262
Nate Begeman07ed4172005-10-10 21:26:48 +00007263 // shl setcc result by log2 n2c
Bill Wendling836ca7d2009-01-30 23:59:18 +00007264 return DAG.getNode(ISD::SHL, DL, N2.getValueType(), Temp,
Dan Gohman002e5d02008-03-13 22:13:53 +00007265 DAG.getConstant(N2C->getAPIntValue().logBase2(),
Owen Anderson95771af2011-02-25 21:41:48 +00007266 getShiftAmountTy(Temp.getValueType())));
Nate Begeman07ed4172005-10-10 21:26:48 +00007267 }
Scott Michelfdc40a02009-02-17 22:15:04 +00007268
Nate Begemanf845b452005-10-08 00:29:44 +00007269 // Check to see if this is the equivalent of setcc
7270 // FIXME: Turn all of these into setcc if setcc if setcc is legal
7271 // otherwise, go ahead with the folds.
Dan Gohman002e5d02008-03-13 22:13:53 +00007272 if (0 && N3C && N3C->isNullValue() && N2C && (N2C->getAPIntValue() == 1ULL)) {
Owen Andersone50ed302009-08-10 22:56:29 +00007273 EVT XType = N0.getValueType();
Duncan Sands25cf2272008-11-24 14:53:14 +00007274 if (!LegalOperations ||
Duncan Sands5480c042009-01-01 15:52:00 +00007275 TLI.isOperationLegal(ISD::SETCC, TLI.getSetCCResultType(XType))) {
Bill Wendling836ca7d2009-01-30 23:59:18 +00007276 SDValue Res = DAG.getSetCC(DL, TLI.getSetCCResultType(XType), N0, N1, CC);
Nate Begemanf845b452005-10-08 00:29:44 +00007277 if (Res.getValueType() != VT)
Bill Wendling836ca7d2009-01-30 23:59:18 +00007278 Res = DAG.getNode(ISD::ZERO_EXTEND, DL, VT, Res);
Nate Begemanf845b452005-10-08 00:29:44 +00007279 return Res;
7280 }
Scott Michelfdc40a02009-02-17 22:15:04 +00007281
Bill Wendling836ca7d2009-01-30 23:59:18 +00007282 // fold (seteq X, 0) -> (srl (ctlz X, log2(size(X))))
Scott Michelfdc40a02009-02-17 22:15:04 +00007283 if (N1C && N1C->isNullValue() && CC == ISD::SETEQ &&
Duncan Sands25cf2272008-11-24 14:53:14 +00007284 (!LegalOperations ||
Duncan Sands184a8762008-06-14 17:48:34 +00007285 TLI.isOperationLegal(ISD::CTLZ, XType))) {
Bill Wendling9729c5a2009-01-31 03:12:48 +00007286 SDValue Ctlz = DAG.getNode(ISD::CTLZ, N0.getDebugLoc(), XType, N0);
Scott Michelfdc40a02009-02-17 22:15:04 +00007287 return DAG.getNode(ISD::SRL, DL, XType, Ctlz,
Duncan Sands83ec4b62008-06-06 12:08:01 +00007288 DAG.getConstant(Log2_32(XType.getSizeInBits()),
Owen Anderson95771af2011-02-25 21:41:48 +00007289 getShiftAmountTy(Ctlz.getValueType())));
Nate Begemanf845b452005-10-08 00:29:44 +00007290 }
Bill Wendling836ca7d2009-01-30 23:59:18 +00007291 // fold (setgt X, 0) -> (srl (and (-X, ~X), size(X)-1))
Scott Michelfdc40a02009-02-17 22:15:04 +00007292 if (N1C && N1C->isNullValue() && CC == ISD::SETGT) {
Bill Wendling836ca7d2009-01-30 23:59:18 +00007293 SDValue NegN0 = DAG.getNode(ISD::SUB, N0.getDebugLoc(),
7294 XType, DAG.getConstant(0, XType), N0);
Bill Wendling7581bfa2009-01-30 23:03:19 +00007295 SDValue NotN0 = DAG.getNOT(N0.getDebugLoc(), N0, XType);
Bill Wendling836ca7d2009-01-30 23:59:18 +00007296 return DAG.getNode(ISD::SRL, DL, XType,
Bill Wendlingfc4b6772009-02-01 11:19:36 +00007297 DAG.getNode(ISD::AND, DL, XType, NegN0, NotN0),
Duncan Sands83ec4b62008-06-06 12:08:01 +00007298 DAG.getConstant(XType.getSizeInBits()-1,
Owen Anderson95771af2011-02-25 21:41:48 +00007299 getShiftAmountTy(XType)));
Nate Begemanf845b452005-10-08 00:29:44 +00007300 }
Bill Wendling836ca7d2009-01-30 23:59:18 +00007301 // fold (setgt X, -1) -> (xor (srl (X, size(X)-1), 1))
Nate Begemanf845b452005-10-08 00:29:44 +00007302 if (N1C && N1C->isAllOnesValue() && CC == ISD::SETGT) {
Bill Wendling9729c5a2009-01-31 03:12:48 +00007303 SDValue Sign = DAG.getNode(ISD::SRL, N0.getDebugLoc(), XType, N0,
Bill Wendling836ca7d2009-01-30 23:59:18 +00007304 DAG.getConstant(XType.getSizeInBits()-1,
Owen Anderson95771af2011-02-25 21:41:48 +00007305 getShiftAmountTy(N0.getValueType())));
Bill Wendling836ca7d2009-01-30 23:59:18 +00007306 return DAG.getNode(ISD::XOR, DL, XType, Sign, DAG.getConstant(1, XType));
Nate Begemanf845b452005-10-08 00:29:44 +00007307 }
7308 }
Scott Michelfdc40a02009-02-17 22:15:04 +00007309
Benjamin Kramercde51102010-07-08 12:09:56 +00007310 // Check to see if this is an integer abs.
7311 // select_cc setg[te] X, 0, X, -X ->
7312 // select_cc setgt X, -1, X, -X ->
7313 // select_cc setl[te] X, 0, -X, X ->
7314 // select_cc setlt X, 1, -X, X ->
Nate Begemanf845b452005-10-08 00:29:44 +00007315 // Y = sra (X, size(X)-1); xor (add (X, Y), Y)
Benjamin Kramercde51102010-07-08 12:09:56 +00007316 if (N1C) {
7317 ConstantSDNode *SubC = NULL;
7318 if (((N1C->isNullValue() && (CC == ISD::SETGT || CC == ISD::SETGE)) ||
7319 (N1C->isAllOnesValue() && CC == ISD::SETGT)) &&
7320 N0 == N2 && N3.getOpcode() == ISD::SUB && N0 == N3.getOperand(1))
7321 SubC = dyn_cast<ConstantSDNode>(N3.getOperand(0));
7322 else if (((N1C->isNullValue() && (CC == ISD::SETLT || CC == ISD::SETLE)) ||
7323 (N1C->isOne() && CC == ISD::SETLT)) &&
7324 N0 == N3 && N2.getOpcode() == ISD::SUB && N0 == N2.getOperand(1))
7325 SubC = dyn_cast<ConstantSDNode>(N2.getOperand(0));
7326
Owen Andersone50ed302009-08-10 22:56:29 +00007327 EVT XType = N0.getValueType();
Benjamin Kramercde51102010-07-08 12:09:56 +00007328 if (SubC && SubC->isNullValue() && XType.isInteger()) {
7329 SDValue Shift = DAG.getNode(ISD::SRA, N0.getDebugLoc(), XType,
7330 N0,
7331 DAG.getConstant(XType.getSizeInBits()-1,
Owen Anderson95771af2011-02-25 21:41:48 +00007332 getShiftAmountTy(N0.getValueType())));
Benjamin Kramercde51102010-07-08 12:09:56 +00007333 SDValue Add = DAG.getNode(ISD::ADD, N0.getDebugLoc(),
7334 XType, N0, Shift);
7335 AddToWorkList(Shift.getNode());
7336 AddToWorkList(Add.getNode());
7337 return DAG.getNode(ISD::XOR, DL, XType, Add, Shift);
Nate Begemanf845b452005-10-08 00:29:44 +00007338 }
7339 }
Scott Michelfdc40a02009-02-17 22:15:04 +00007340
Dan Gohman475871a2008-07-27 21:46:04 +00007341 return SDValue();
Nate Begeman44728a72005-09-19 22:34:01 +00007342}
7343
Evan Chengfa1eb272007-02-08 22:13:59 +00007344/// SimplifySetCC - This is a stub for TargetLowering::SimplifySetCC.
Owen Andersone50ed302009-08-10 22:56:29 +00007345SDValue DAGCombiner::SimplifySetCC(EVT VT, SDValue N0,
Dan Gohman475871a2008-07-27 21:46:04 +00007346 SDValue N1, ISD::CondCode Cond,
Dale Johannesenff97d4f2009-02-03 00:47:48 +00007347 DebugLoc DL, bool foldBooleans) {
Scott Michelfdc40a02009-02-17 22:15:04 +00007348 TargetLowering::DAGCombinerInfo
Jakob Stoklund Olesen78d12642009-07-24 18:22:59 +00007349 DagCombineInfo(DAG, !LegalTypes, !LegalOperations, false, this);
Dale Johannesenff97d4f2009-02-03 00:47:48 +00007350 return TLI.SimplifySetCC(VT, N0, N1, Cond, foldBooleans, DagCombineInfo, DL);
Nate Begeman452d7beb2005-09-16 00:54:12 +00007351}
7352
Nate Begeman69575232005-10-20 02:15:44 +00007353/// BuildSDIVSequence - Given an ISD::SDIV node expressing a divide by constant,
7354/// return a DAG expression to select that will generate the same value by
7355/// multiplying by a magic number. See:
7356/// <http://the.wall.riscom.net/books/proc/ppc/cwg/code2.html>
Dan Gohman475871a2008-07-27 21:46:04 +00007357SDValue DAGCombiner::BuildSDIV(SDNode *N) {
Andrew Lenharth232c9102006-06-12 16:07:18 +00007358 std::vector<SDNode*> Built;
Dan Gohman475871a2008-07-27 21:46:04 +00007359 SDValue S = TLI.BuildSDIV(N, DAG, &Built);
Andrew Lenharthdae9cbe2006-05-16 17:42:15 +00007360
Andrew Lenharth232c9102006-06-12 16:07:18 +00007361 for (std::vector<SDNode*>::iterator ii = Built.begin(), ee = Built.end();
Andrew Lenharthdae9cbe2006-05-16 17:42:15 +00007362 ii != ee; ++ii)
7363 AddToWorkList(*ii);
7364 return S;
Nate Begeman69575232005-10-20 02:15:44 +00007365}
7366
7367/// BuildUDIVSequence - Given an ISD::UDIV node expressing a divide by constant,
7368/// return a DAG expression to select that will generate the same value by
7369/// multiplying by a magic number. See:
7370/// <http://the.wall.riscom.net/books/proc/ppc/cwg/code2.html>
Dan Gohman475871a2008-07-27 21:46:04 +00007371SDValue DAGCombiner::BuildUDIV(SDNode *N) {
Andrew Lenharth232c9102006-06-12 16:07:18 +00007372 std::vector<SDNode*> Built;
Dan Gohman475871a2008-07-27 21:46:04 +00007373 SDValue S = TLI.BuildUDIV(N, DAG, &Built);
Nate Begeman69575232005-10-20 02:15:44 +00007374
Andrew Lenharth232c9102006-06-12 16:07:18 +00007375 for (std::vector<SDNode*>::iterator ii = Built.begin(), ee = Built.end();
Andrew Lenharthdae9cbe2006-05-16 17:42:15 +00007376 ii != ee; ++ii)
7377 AddToWorkList(*ii);
7378 return S;
Nate Begeman69575232005-10-20 02:15:44 +00007379}
7380
Nate Begemancc66cdd2009-09-25 06:05:26 +00007381/// FindBaseOffset - Return true if base is a frame index, which is known not
Eric Christopher503a64d2010-12-09 04:48:06 +00007382// to alias with anything but itself. Provides base object and offset as
7383// results.
Nate Begemancc66cdd2009-09-25 06:05:26 +00007384static bool FindBaseOffset(SDValue Ptr, SDValue &Base, int64_t &Offset,
Dan Gohman46510a72010-04-15 01:51:59 +00007385 const GlobalValue *&GV, void *&CV) {
Jim Laskey71382342006-10-07 23:37:56 +00007386 // Assume it is a primitive operation.
Nate Begemancc66cdd2009-09-25 06:05:26 +00007387 Base = Ptr; Offset = 0; GV = 0; CV = 0;
Scott Michelfdc40a02009-02-17 22:15:04 +00007388
Jim Laskey71382342006-10-07 23:37:56 +00007389 // If it's an adding a simple constant then integrate the offset.
7390 if (Base.getOpcode() == ISD::ADD) {
7391 if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Base.getOperand(1))) {
7392 Base = Base.getOperand(0);
Dan Gohmanf5aeb1a2008-09-12 16:56:44 +00007393 Offset += C->getZExtValue();
Jim Laskey71382342006-10-07 23:37:56 +00007394 }
7395 }
Wesley Peckbf17cfa2010-11-23 03:31:01 +00007396
Nate Begemancc66cdd2009-09-25 06:05:26 +00007397 // Return the underlying GlobalValue, and update the Offset. Return false
7398 // for GlobalAddressSDNode since the same GlobalAddress may be represented
7399 // by multiple nodes with different offsets.
7400 if (GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(Base)) {
7401 GV = G->getGlobal();
7402 Offset += G->getOffset();
7403 return false;
7404 }
Scott Michelfdc40a02009-02-17 22:15:04 +00007405
Nate Begemancc66cdd2009-09-25 06:05:26 +00007406 // Return the underlying Constant value, and update the Offset. Return false
7407 // for ConstantSDNodes since the same constant pool entry may be represented
7408 // by multiple nodes with different offsets.
7409 if (ConstantPoolSDNode *C = dyn_cast<ConstantPoolSDNode>(Base)) {
7410 CV = C->isMachineConstantPoolEntry() ? (void *)C->getMachineCPVal()
7411 : (void *)C->getConstVal();
7412 Offset += C->getOffset();
7413 return false;
7414 }
Jim Laskey71382342006-10-07 23:37:56 +00007415 // If it's any of the following then it can't alias with anything but itself.
Nate Begemancc66cdd2009-09-25 06:05:26 +00007416 return isa<FrameIndexSDNode>(Base);
Jim Laskey71382342006-10-07 23:37:56 +00007417}
7418
7419/// isAlias - Return true if there is any possibility that the two addresses
7420/// overlap.
Dan Gohman475871a2008-07-27 21:46:04 +00007421bool DAGCombiner::isAlias(SDValue Ptr1, int64_t Size1,
Jim Laskey096c22e2006-10-18 12:29:57 +00007422 const Value *SrcValue1, int SrcValueOffset1,
Nate Begemanb6aef5c2009-09-15 00:18:30 +00007423 unsigned SrcValueAlign1,
Dan Gohmanf96e4bd2010-10-20 00:31:05 +00007424 const MDNode *TBAAInfo1,
Dan Gohman475871a2008-07-27 21:46:04 +00007425 SDValue Ptr2, int64_t Size2,
Nate Begemanb6aef5c2009-09-15 00:18:30 +00007426 const Value *SrcValue2, int SrcValueOffset2,
Dan Gohmanf96e4bd2010-10-20 00:31:05 +00007427 unsigned SrcValueAlign2,
7428 const MDNode *TBAAInfo2) const {
Jim Laskey71382342006-10-07 23:37:56 +00007429 // If they are the same then they must be aliases.
7430 if (Ptr1 == Ptr2) return true;
Scott Michelfdc40a02009-02-17 22:15:04 +00007431
Jim Laskey71382342006-10-07 23:37:56 +00007432 // Gather base node and offset information.
Dan Gohman475871a2008-07-27 21:46:04 +00007433 SDValue Base1, Base2;
Jim Laskey71382342006-10-07 23:37:56 +00007434 int64_t Offset1, Offset2;
Dan Gohman46510a72010-04-15 01:51:59 +00007435 const GlobalValue *GV1, *GV2;
Nate Begemancc66cdd2009-09-25 06:05:26 +00007436 void *CV1, *CV2;
7437 bool isFrameIndex1 = FindBaseOffset(Ptr1, Base1, Offset1, GV1, CV1);
7438 bool isFrameIndex2 = FindBaseOffset(Ptr2, Base2, Offset2, GV2, CV2);
Scott Michelfdc40a02009-02-17 22:15:04 +00007439
Nate Begemancc66cdd2009-09-25 06:05:26 +00007440 // If they have a same base address then check to see if they overlap.
7441 if (Base1 == Base2 || (GV1 && (GV1 == GV2)) || (CV1 && (CV1 == CV2)))
Bill Wendling836ca7d2009-01-30 23:59:18 +00007442 return !((Offset1 + Size1) <= Offset2 || (Offset2 + Size2) <= Offset1);
Scott Michelfdc40a02009-02-17 22:15:04 +00007443
Owen Anderson4a9f1502010-09-20 20:39:59 +00007444 // It is possible for different frame indices to alias each other, mostly
7445 // when tail call optimization reuses return address slots for arguments.
7446 // To catch this case, look up the actual index of frame indices to compute
7447 // the real alias relationship.
7448 if (isFrameIndex1 && isFrameIndex2) {
7449 MachineFrameInfo *MFI = DAG.getMachineFunction().getFrameInfo();
7450 Offset1 += MFI->getObjectOffset(cast<FrameIndexSDNode>(Base1)->getIndex());
7451 Offset2 += MFI->getObjectOffset(cast<FrameIndexSDNode>(Base2)->getIndex());
7452 return !((Offset1 + Size1) <= Offset2 || (Offset2 + Size2) <= Offset1);
7453 }
7454
Wesley Peckbf17cfa2010-11-23 03:31:01 +00007455 // Otherwise, if we know what the bases are, and they aren't identical, then
Owen Anderson4a9f1502010-09-20 20:39:59 +00007456 // we know they cannot alias.
Nate Begemancc66cdd2009-09-25 06:05:26 +00007457 if ((isFrameIndex1 || CV1 || GV1) && (isFrameIndex2 || CV2 || GV2))
7458 return false;
Jim Laskey096c22e2006-10-18 12:29:57 +00007459
Nate Begemanb6aef5c2009-09-15 00:18:30 +00007460 // If we know required SrcValue1 and SrcValue2 have relatively large alignment
7461 // compared to the size and offset of the access, we may be able to prove they
7462 // do not alias. This check is conservative for now to catch cases created by
7463 // splitting vector types.
7464 if ((SrcValueAlign1 == SrcValueAlign2) &&
7465 (SrcValueOffset1 != SrcValueOffset2) &&
7466 (Size1 == Size2) && (SrcValueAlign1 > Size1)) {
7467 int64_t OffAlign1 = SrcValueOffset1 % SrcValueAlign1;
7468 int64_t OffAlign2 = SrcValueOffset2 % SrcValueAlign1;
Wesley Peckbf17cfa2010-11-23 03:31:01 +00007469
Nate Begemanb6aef5c2009-09-15 00:18:30 +00007470 // There is no overlap between these relatively aligned accesses of similar
7471 // size, return no alias.
7472 if ((OffAlign1 + Size1) <= OffAlign2 || (OffAlign2 + Size2) <= OffAlign1)
7473 return false;
7474 }
Wesley Peckbf17cfa2010-11-23 03:31:01 +00007475
Jim Laskey07a27092006-10-18 19:08:31 +00007476 if (CombinerGlobalAA) {
7477 // Use alias analysis information.
Dan Gohmane9c8fa02007-08-27 16:32:11 +00007478 int64_t MinOffset = std::min(SrcValueOffset1, SrcValueOffset2);
7479 int64_t Overlap1 = Size1 + SrcValueOffset1 - MinOffset;
7480 int64_t Overlap2 = Size2 + SrcValueOffset2 - MinOffset;
Scott Michelfdc40a02009-02-17 22:15:04 +00007481 AliasAnalysis::AliasResult AAResult =
Dan Gohmanf96e4bd2010-10-20 00:31:05 +00007482 AA.alias(AliasAnalysis::Location(SrcValue1, Overlap1, TBAAInfo1),
7483 AliasAnalysis::Location(SrcValue2, Overlap2, TBAAInfo2));
Jim Laskey07a27092006-10-18 19:08:31 +00007484 if (AAResult == AliasAnalysis::NoAlias)
7485 return false;
7486 }
Jim Laskey096c22e2006-10-18 12:29:57 +00007487
7488 // Otherwise we have to assume they alias.
7489 return true;
Jim Laskey71382342006-10-07 23:37:56 +00007490}
7491
7492/// FindAliasInfo - Extracts the relevant alias information from the memory
7493/// node. Returns true if the operand was a load.
Jim Laskey7ca56af2006-10-11 13:47:09 +00007494bool DAGCombiner::FindAliasInfo(SDNode *N,
Dan Gohman475871a2008-07-27 21:46:04 +00007495 SDValue &Ptr, int64_t &Size,
Wesley Peckbf17cfa2010-11-23 03:31:01 +00007496 const Value *&SrcValue,
Nate Begemanb6aef5c2009-09-15 00:18:30 +00007497 int &SrcValueOffset,
Dan Gohmanf96e4bd2010-10-20 00:31:05 +00007498 unsigned &SrcValueAlign,
7499 const MDNode *&TBAAInfo) const {
Jim Laskey7ca56af2006-10-11 13:47:09 +00007500 if (LoadSDNode *LD = dyn_cast<LoadSDNode>(N)) {
7501 Ptr = LD->getBasePtr();
Duncan Sands83ec4b62008-06-06 12:08:01 +00007502 Size = LD->getMemoryVT().getSizeInBits() >> 3;
Jim Laskey7ca56af2006-10-11 13:47:09 +00007503 SrcValue = LD->getSrcValue();
Jim Laskey096c22e2006-10-18 12:29:57 +00007504 SrcValueOffset = LD->getSrcValueOffset();
Nate Begemanb6aef5c2009-09-15 00:18:30 +00007505 SrcValueAlign = LD->getOriginalAlignment();
Dan Gohmanf96e4bd2010-10-20 00:31:05 +00007506 TBAAInfo = LD->getTBAAInfo();
Jim Laskey71382342006-10-07 23:37:56 +00007507 return true;
Jim Laskey7ca56af2006-10-11 13:47:09 +00007508 } else if (StoreSDNode *ST = dyn_cast<StoreSDNode>(N)) {
Jim Laskey7ca56af2006-10-11 13:47:09 +00007509 Ptr = ST->getBasePtr();
Duncan Sands83ec4b62008-06-06 12:08:01 +00007510 Size = ST->getMemoryVT().getSizeInBits() >> 3;
Jim Laskey7ca56af2006-10-11 13:47:09 +00007511 SrcValue = ST->getSrcValue();
Jim Laskey096c22e2006-10-18 12:29:57 +00007512 SrcValueOffset = ST->getSrcValueOffset();
Nate Begemanb6aef5c2009-09-15 00:18:30 +00007513 SrcValueAlign = ST->getOriginalAlignment();
Dan Gohmanf96e4bd2010-10-20 00:31:05 +00007514 TBAAInfo = ST->getTBAAInfo();
Jim Laskey7ca56af2006-10-11 13:47:09 +00007515 } else {
Torok Edwinc23197a2009-07-14 16:55:14 +00007516 llvm_unreachable("FindAliasInfo expected a memory operand");
Jim Laskey71382342006-10-07 23:37:56 +00007517 }
Scott Michelfdc40a02009-02-17 22:15:04 +00007518
Jim Laskey71382342006-10-07 23:37:56 +00007519 return false;
7520}
7521
Jim Laskey6ff23e52006-10-04 16:53:27 +00007522/// GatherAllAliases - Walk up chain skipping non-aliasing memory nodes,
7523/// looking for aliasing nodes and adding them to the Aliases vector.
Dan Gohman475871a2008-07-27 21:46:04 +00007524void DAGCombiner::GatherAllAliases(SDNode *N, SDValue OriginalChain,
7525 SmallVector<SDValue, 8> &Aliases) {
7526 SmallVector<SDValue, 8> Chains; // List of chains to visit.
Nate Begemanb6aef5c2009-09-15 00:18:30 +00007527 SmallPtrSet<SDNode *, 16> Visited; // Visited node set.
Scott Michelfdc40a02009-02-17 22:15:04 +00007528
Jim Laskey279f0532006-09-25 16:29:54 +00007529 // Get alias information for node.
Dan Gohman475871a2008-07-27 21:46:04 +00007530 SDValue Ptr;
Nate Begemanb6aef5c2009-09-15 00:18:30 +00007531 int64_t Size;
7532 const Value *SrcValue;
7533 int SrcValueOffset;
7534 unsigned SrcValueAlign;
Dan Gohmanf96e4bd2010-10-20 00:31:05 +00007535 const MDNode *SrcTBAAInfo;
Wesley Peckbf17cfa2010-11-23 03:31:01 +00007536 bool IsLoad = FindAliasInfo(N, Ptr, Size, SrcValue, SrcValueOffset,
Dan Gohmanf96e4bd2010-10-20 00:31:05 +00007537 SrcValueAlign, SrcTBAAInfo);
Jim Laskey279f0532006-09-25 16:29:54 +00007538
Jim Laskey6ff23e52006-10-04 16:53:27 +00007539 // Starting off.
Jim Laskeybc588b82006-10-05 15:07:25 +00007540 Chains.push_back(OriginalChain);
Nate Begeman677c89d2009-10-12 05:53:58 +00007541 unsigned Depth = 0;
Wesley Peckbf17cfa2010-11-23 03:31:01 +00007542
Jim Laskeybc588b82006-10-05 15:07:25 +00007543 // Look at each chain and determine if it is an alias. If so, add it to the
7544 // aliases list. If not, then continue up the chain looking for the next
Scott Michelfdc40a02009-02-17 22:15:04 +00007545 // candidate.
Jim Laskeybc588b82006-10-05 15:07:25 +00007546 while (!Chains.empty()) {
Dan Gohman475871a2008-07-27 21:46:04 +00007547 SDValue Chain = Chains.back();
Jim Laskeybc588b82006-10-05 15:07:25 +00007548 Chains.pop_back();
Wesley Peckbf17cfa2010-11-23 03:31:01 +00007549
7550 // For TokenFactor nodes, look at each operand and only continue up the
7551 // chain until we find two aliases. If we've seen two aliases, assume we'll
Nate Begeman677c89d2009-10-12 05:53:58 +00007552 // find more and revert to original chain since the xform is unlikely to be
7553 // profitable.
Wesley Peckbf17cfa2010-11-23 03:31:01 +00007554 //
7555 // FIXME: The depth check could be made to return the last non-aliasing
Nate Begeman677c89d2009-10-12 05:53:58 +00007556 // chain we found before we hit a tokenfactor rather than the original
7557 // chain.
7558 if (Depth > 6 || Aliases.size() == 2) {
7559 Aliases.clear();
7560 Aliases.push_back(OriginalChain);
7561 break;
7562 }
Scott Michelfdc40a02009-02-17 22:15:04 +00007563
Nate Begemanb6aef5c2009-09-15 00:18:30 +00007564 // Don't bother if we've been before.
7565 if (!Visited.insert(Chain.getNode()))
7566 continue;
Scott Michelfdc40a02009-02-17 22:15:04 +00007567
Jim Laskeybc588b82006-10-05 15:07:25 +00007568 switch (Chain.getOpcode()) {
7569 case ISD::EntryToken:
7570 // Entry token is ideal chain operand, but handled in FindBetterChain.
7571 break;
Scott Michelfdc40a02009-02-17 22:15:04 +00007572
Jim Laskeybc588b82006-10-05 15:07:25 +00007573 case ISD::LOAD:
7574 case ISD::STORE: {
7575 // Get alias information for Chain.
Dan Gohman475871a2008-07-27 21:46:04 +00007576 SDValue OpPtr;
Nate Begemanb6aef5c2009-09-15 00:18:30 +00007577 int64_t OpSize;
7578 const Value *OpSrcValue;
7579 int OpSrcValueOffset;
7580 unsigned OpSrcValueAlign;
Dan Gohmanf96e4bd2010-10-20 00:31:05 +00007581 const MDNode *OpSrcTBAAInfo;
Gabor Greifba36cb52008-08-28 21:40:38 +00007582 bool IsOpLoad = FindAliasInfo(Chain.getNode(), OpPtr, OpSize,
Nate Begemanb6aef5c2009-09-15 00:18:30 +00007583 OpSrcValue, OpSrcValueOffset,
Dan Gohmanf96e4bd2010-10-20 00:31:05 +00007584 OpSrcValueAlign,
7585 OpSrcTBAAInfo);
Scott Michelfdc40a02009-02-17 22:15:04 +00007586
Jim Laskeybc588b82006-10-05 15:07:25 +00007587 // If chain is alias then stop here.
7588 if (!(IsLoad && IsOpLoad) &&
Nate Begemanb6aef5c2009-09-15 00:18:30 +00007589 isAlias(Ptr, Size, SrcValue, SrcValueOffset, SrcValueAlign,
Dan Gohmanf96e4bd2010-10-20 00:31:05 +00007590 SrcTBAAInfo,
Nate Begemanb6aef5c2009-09-15 00:18:30 +00007591 OpPtr, OpSize, OpSrcValue, OpSrcValueOffset,
Dan Gohmanf96e4bd2010-10-20 00:31:05 +00007592 OpSrcValueAlign, OpSrcTBAAInfo)) {
Jim Laskeybc588b82006-10-05 15:07:25 +00007593 Aliases.push_back(Chain);
7594 } else {
7595 // Look further up the chain.
Scott Michelfdc40a02009-02-17 22:15:04 +00007596 Chains.push_back(Chain.getOperand(0));
Nate Begeman677c89d2009-10-12 05:53:58 +00007597 ++Depth;
Jim Laskey279f0532006-09-25 16:29:54 +00007598 }
Jim Laskeybc588b82006-10-05 15:07:25 +00007599 break;
7600 }
Scott Michelfdc40a02009-02-17 22:15:04 +00007601
Jim Laskeybc588b82006-10-05 15:07:25 +00007602 case ISD::TokenFactor:
Nate Begemanb6aef5c2009-09-15 00:18:30 +00007603 // We have to check each of the operands of the token factor for "small"
7604 // token factors, so we queue them up. Adding the operands to the queue
7605 // (stack) in reverse order maintains the original order and increases the
7606 // likelihood that getNode will find a matching token factor (CSE.)
7607 if (Chain.getNumOperands() > 16) {
7608 Aliases.push_back(Chain);
7609 break;
7610 }
Jim Laskeybc588b82006-10-05 15:07:25 +00007611 for (unsigned n = Chain.getNumOperands(); n;)
7612 Chains.push_back(Chain.getOperand(--n));
Nate Begeman677c89d2009-10-12 05:53:58 +00007613 ++Depth;
Jim Laskeybc588b82006-10-05 15:07:25 +00007614 break;
Scott Michelfdc40a02009-02-17 22:15:04 +00007615
Jim Laskeybc588b82006-10-05 15:07:25 +00007616 default:
7617 // For all other instructions we will just have to take what we can get.
7618 Aliases.push_back(Chain);
7619 break;
Jim Laskey279f0532006-09-25 16:29:54 +00007620 }
7621 }
Jim Laskey6ff23e52006-10-04 16:53:27 +00007622}
7623
7624/// FindBetterChain - Walk up chain skipping non-aliasing memory nodes, looking
7625/// for a better chain (aliasing node.)
Dan Gohman475871a2008-07-27 21:46:04 +00007626SDValue DAGCombiner::FindBetterChain(SDNode *N, SDValue OldChain) {
7627 SmallVector<SDValue, 8> Aliases; // Ops for replacing token factor.
Scott Michelfdc40a02009-02-17 22:15:04 +00007628
Jim Laskey6ff23e52006-10-04 16:53:27 +00007629 // Accumulate all the aliases to this node.
7630 GatherAllAliases(N, OldChain, Aliases);
Scott Michelfdc40a02009-02-17 22:15:04 +00007631
Jim Laskey6ff23e52006-10-04 16:53:27 +00007632 if (Aliases.size() == 0) {
7633 // If no operands then chain to entry token.
7634 return DAG.getEntryNode();
7635 } else if (Aliases.size() == 1) {
7636 // If a single operand then chain to it. We don't need to revisit it.
7637 return Aliases[0];
7638 }
Wesley Peckbf17cfa2010-11-23 03:31:01 +00007639
Jim Laskey6ff23e52006-10-04 16:53:27 +00007640 // Construct a custom tailored token factor.
Wesley Peckbf17cfa2010-11-23 03:31:01 +00007641 return DAG.getNode(ISD::TokenFactor, N->getDebugLoc(), MVT::Other,
Nate Begemanb6aef5c2009-09-15 00:18:30 +00007642 &Aliases[0], Aliases.size());
Jim Laskey279f0532006-09-25 16:29:54 +00007643}
7644
Nate Begeman1d4d4142005-09-01 00:19:25 +00007645// SelectionDAG::Combine - This is the entry point for the file.
7646//
Bill Wendlingbe8cc2a2009-04-29 00:15:41 +00007647void SelectionDAG::Combine(CombineLevel Level, AliasAnalysis &AA,
Bill Wendling98a366d2009-04-29 23:29:43 +00007648 CodeGenOpt::Level OptLevel) {
Nate Begeman1d4d4142005-09-01 00:19:25 +00007649 /// run - This is the main entry point to this class.
7650 ///
Bill Wendlingbe8cc2a2009-04-29 00:15:41 +00007651 DAGCombiner(*this, AA, OptLevel).Run(Level);
Nate Begeman1d4d4142005-09-01 00:19:25 +00007652}