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Chris Lattner530d4bf2003-05-29 15:11:31 +00001//===- InlineFunction.cpp - Code to perform function inlining -------------===//
Misha Brukmanb1c93172005-04-21 23:48:37 +00002//
John Criswell482202a2003-10-20 19:43:21 +00003// The LLVM Compiler Infrastructure
4//
Chris Lattnerf3ebc3f2007-12-29 20:36:04 +00005// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
Misha Brukmanb1c93172005-04-21 23:48:37 +00007//
John Criswell482202a2003-10-20 19:43:21 +00008//===----------------------------------------------------------------------===//
Chris Lattner530d4bf2003-05-29 15:11:31 +00009//
10// This file implements inlining of a function into a call site, resolving
11// parameters and the return value as appropriate.
12//
Chris Lattner530d4bf2003-05-29 15:11:31 +000013//===----------------------------------------------------------------------===//
14
15#include "llvm/Transforms/Utils/Cloning.h"
Chandler Carruthed0881b2012-12-03 16:50:05 +000016#include "llvm/ADT/SmallVector.h"
17#include "llvm/ADT/StringExtras.h"
18#include "llvm/Analysis/CallGraph.h"
19#include "llvm/Analysis/InstructionSimplify.h"
Bill Wendlinge38859d2012-06-28 00:05:13 +000020#include "llvm/DebugInfo.h"
Chandler Carruth9fb823b2013-01-02 11:36:10 +000021#include "llvm/IR/Attributes.h"
22#include "llvm/IR/Constants.h"
23#include "llvm/IR/DataLayout.h"
24#include "llvm/IR/DerivedTypes.h"
25#include "llvm/IR/IRBuilder.h"
26#include "llvm/IR/Instructions.h"
27#include "llvm/IR/IntrinsicInst.h"
28#include "llvm/IR/Intrinsics.h"
29#include "llvm/IR/Module.h"
Chris Lattner0cc265e2003-08-24 06:59:16 +000030#include "llvm/Support/CallSite.h"
Chandler Carruthaafe0912012-06-29 12:38:19 +000031#include "llvm/Transforms/Utils/Local.h"
Chris Lattnerdf3c3422004-01-09 06:12:26 +000032using namespace llvm;
Chris Lattner530d4bf2003-05-29 15:11:31 +000033
Eric Christopherf16bee82012-03-26 19:09:38 +000034bool llvm::InlineFunction(CallInst *CI, InlineFunctionInfo &IFI,
35 bool InsertLifetime) {
Chad Rosier07d37bc2012-02-25 02:56:01 +000036 return InlineFunction(CallSite(CI), IFI, InsertLifetime);
Chris Lattner0841fb12006-01-14 20:07:50 +000037}
Eric Christopherf16bee82012-03-26 19:09:38 +000038bool llvm::InlineFunction(InvokeInst *II, InlineFunctionInfo &IFI,
39 bool InsertLifetime) {
Chad Rosier07d37bc2012-02-25 02:56:01 +000040 return InlineFunction(CallSite(II), IFI, InsertLifetime);
Chris Lattner0841fb12006-01-14 20:07:50 +000041}
Chris Lattner0cc265e2003-08-24 06:59:16 +000042
John McCallbd04b742011-05-27 18:34:38 +000043namespace {
44 /// A class for recording information about inlining through an invoke.
45 class InvokeInliningInfo {
Dmitri Gribenkodbeafa72012-06-09 00:01:45 +000046 BasicBlock *OuterResumeDest; ///< Destination of the invoke's unwind.
47 BasicBlock *InnerResumeDest; ///< Destination for the callee's resume.
48 LandingPadInst *CallerLPad; ///< LandingPadInst associated with the invoke.
49 PHINode *InnerEHValuesPHI; ///< PHI for EH values from landingpad insts.
Bill Wendling0c2d82b2012-01-31 01:22:03 +000050 SmallVector<Value*, 8> UnwindDestPHIValues;
Bill Wendlingfa284402011-07-28 07:31:46 +000051
Bill Wendling55421f02011-08-14 08:01:36 +000052 public:
53 InvokeInliningInfo(InvokeInst *II)
Bill Wendlingea6e9352012-01-31 01:25:54 +000054 : OuterResumeDest(II->getUnwindDest()), InnerResumeDest(0),
Bill Wendling55421f02011-08-14 08:01:36 +000055 CallerLPad(0), InnerEHValuesPHI(0) {
56 // If there are PHI nodes in the unwind destination block, we need to keep
57 // track of which values came into them from the invoke before removing
58 // the edge from this block.
59 llvm::BasicBlock *InvokeBB = II->getParent();
Bill Wendlingea6e9352012-01-31 01:25:54 +000060 BasicBlock::iterator I = OuterResumeDest->begin();
Bill Wendling55421f02011-08-14 08:01:36 +000061 for (; isa<PHINode>(I); ++I) {
John McCallbd04b742011-05-27 18:34:38 +000062 // Save the value to use for this edge.
Bill Wendling55421f02011-08-14 08:01:36 +000063 PHINode *PHI = cast<PHINode>(I);
64 UnwindDestPHIValues.push_back(PHI->getIncomingValueForBlock(InvokeBB));
65 }
66
Bill Wendlingf3cae512012-01-31 00:56:53 +000067 CallerLPad = cast<LandingPadInst>(I);
John McCallbd04b742011-05-27 18:34:38 +000068 }
69
Bill Wendlingea6e9352012-01-31 01:25:54 +000070 /// getOuterResumeDest - The outer unwind destination is the target of
71 /// unwind edges introduced for calls within the inlined function.
Bill Wendling0c2d82b2012-01-31 01:22:03 +000072 BasicBlock *getOuterResumeDest() const {
Bill Wendlingea6e9352012-01-31 01:25:54 +000073 return OuterResumeDest;
John McCallbd04b742011-05-27 18:34:38 +000074 }
75
Bill Wendling3fd879d2012-01-31 01:48:40 +000076 BasicBlock *getInnerResumeDest();
Bill Wendling55421f02011-08-14 08:01:36 +000077
78 LandingPadInst *getLandingPadInst() const { return CallerLPad; }
79
Bill Wendling55421f02011-08-14 08:01:36 +000080 /// forwardResume - Forward the 'resume' instruction to the caller's landing
81 /// pad block. When the landing pad block has only one predecessor, this is
82 /// a simple branch. When there is more than one predecessor, we need to
83 /// split the landing pad block after the landingpad instruction and jump
84 /// to there.
Bill Wendling56f15bf2013-03-22 20:31:05 +000085 void forwardResume(ResumeInst *RI,
86 SmallPtrSet<LandingPadInst*, 16> &InlinedLPads);
Bill Wendling55421f02011-08-14 08:01:36 +000087
88 /// addIncomingPHIValuesFor - Add incoming-PHI values to the unwind
89 /// destination block for the given basic block, using the values for the
90 /// original invoke's source block.
John McCallbd04b742011-05-27 18:34:38 +000091 void addIncomingPHIValuesFor(BasicBlock *BB) const {
Bill Wendlingea6e9352012-01-31 01:25:54 +000092 addIncomingPHIValuesForInto(BB, OuterResumeDest);
John McCall046c47e2011-05-28 07:45:59 +000093 }
Bill Wendlingad088e62011-07-30 05:42:50 +000094
John McCall046c47e2011-05-28 07:45:59 +000095 void addIncomingPHIValuesForInto(BasicBlock *src, BasicBlock *dest) const {
96 BasicBlock::iterator I = dest->begin();
John McCallbd04b742011-05-27 18:34:38 +000097 for (unsigned i = 0, e = UnwindDestPHIValues.size(); i != e; ++i, ++I) {
Bill Wendlingad088e62011-07-30 05:42:50 +000098 PHINode *phi = cast<PHINode>(I);
99 phi->addIncoming(UnwindDestPHIValues[i], src);
John McCallbd04b742011-05-27 18:34:38 +0000100 }
101 }
102 };
103}
104
Bill Wendling3fd879d2012-01-31 01:48:40 +0000105/// getInnerResumeDest - Get or create a target for the branch from ResumeInsts.
106BasicBlock *InvokeInliningInfo::getInnerResumeDest() {
Bill Wendling55421f02011-08-14 08:01:36 +0000107 if (InnerResumeDest) return InnerResumeDest;
108
109 // Split the landing pad.
110 BasicBlock::iterator SplitPoint = CallerLPad; ++SplitPoint;
111 InnerResumeDest =
112 OuterResumeDest->splitBasicBlock(SplitPoint,
113 OuterResumeDest->getName() + ".body");
114
115 // The number of incoming edges we expect to the inner landing pad.
116 const unsigned PHICapacity = 2;
117
118 // Create corresponding new PHIs for all the PHIs in the outer landing pad.
119 BasicBlock::iterator InsertPoint = InnerResumeDest->begin();
120 BasicBlock::iterator I = OuterResumeDest->begin();
121 for (unsigned i = 0, e = UnwindDestPHIValues.size(); i != e; ++i, ++I) {
122 PHINode *OuterPHI = cast<PHINode>(I);
123 PHINode *InnerPHI = PHINode::Create(OuterPHI->getType(), PHICapacity,
124 OuterPHI->getName() + ".lpad-body",
125 InsertPoint);
126 OuterPHI->replaceAllUsesWith(InnerPHI);
127 InnerPHI->addIncoming(OuterPHI, OuterResumeDest);
128 }
129
130 // Create a PHI for the exception values.
131 InnerEHValuesPHI = PHINode::Create(CallerLPad->getType(), PHICapacity,
132 "eh.lpad-body", InsertPoint);
133 CallerLPad->replaceAllUsesWith(InnerEHValuesPHI);
134 InnerEHValuesPHI->addIncoming(CallerLPad, OuterResumeDest);
135
136 // All done.
137 return InnerResumeDest;
138}
139
140/// forwardResume - Forward the 'resume' instruction to the caller's landing pad
141/// block. When the landing pad block has only one predecessor, this is a simple
142/// branch. When there is more than one predecessor, we need to split the
143/// landing pad block after the landingpad instruction and jump to there.
Bill Wendling173c71f2013-03-21 23:30:12 +0000144void InvokeInliningInfo::forwardResume(ResumeInst *RI,
Bill Wendling56f15bf2013-03-22 20:31:05 +0000145 SmallPtrSet<LandingPadInst*, 16> &InlinedLPads) {
Bill Wendling3fd879d2012-01-31 01:48:40 +0000146 BasicBlock *Dest = getInnerResumeDest();
Bill Wendling173c71f2013-03-21 23:30:12 +0000147 LandingPadInst *OuterLPad = getLandingPadInst();
Bill Wendling55421f02011-08-14 08:01:36 +0000148 BasicBlock *Src = RI->getParent();
149
150 BranchInst::Create(Dest, Src);
151
152 // Update the PHIs in the destination. They were inserted in an order which
153 // makes this work.
154 addIncomingPHIValuesForInto(Src, Dest);
155
156 InnerEHValuesPHI->addIncoming(RI->getOperand(0), Src);
157 RI->eraseFromParent();
Bill Wendling173c71f2013-03-21 23:30:12 +0000158
Bill Wendling56f15bf2013-03-22 20:31:05 +0000159 // Append the clauses from the outer landing pad instruction into the inlined
160 // landing pad instructions.
Bill Wendling173c71f2013-03-21 23:30:12 +0000161 for (SmallPtrSet<LandingPadInst*, 16>::iterator I = InlinedLPads.begin(),
162 E = InlinedLPads.end(); I != E; ++I) {
163 LandingPadInst *InlinedLPad = *I;
164 for (unsigned OuterIdx = 0, OuterNum = OuterLPad->getNumClauses();
Bill Wendling56f15bf2013-03-22 20:31:05 +0000165 OuterIdx != OuterNum; ++OuterIdx)
166 InlinedLPad->addClause(OuterLPad->getClause(OuterIdx));
Bill Wendling173c71f2013-03-21 23:30:12 +0000167 }
Bill Wendling55421f02011-08-14 08:01:36 +0000168}
169
Chris Lattner5eef6ad2009-08-27 03:51:50 +0000170/// HandleCallsInBlockInlinedThroughInvoke - When we inline a basic block into
Eric Christopher66d8555f2009-09-06 22:20:54 +0000171/// an invoke, we have to turn all of the calls that can throw into
Chris Lattner5eef6ad2009-08-27 03:51:50 +0000172/// invokes. This function analyze BB to see if there are any calls, and if so,
173/// it rewrites them to be invokes that jump to InvokeDest and fills in the PHI
Chris Lattner8900f3e2009-09-01 18:44:06 +0000174/// nodes in that block with the values specified in InvokeDestPHIValues.
Mark Seabornd91fa222013-12-02 20:50:59 +0000175static void HandleCallsInBlockInlinedThroughInvoke(BasicBlock *BB,
John McCallbd04b742011-05-27 18:34:38 +0000176 InvokeInliningInfo &Invoke) {
Bill Wendling55421f02011-08-14 08:01:36 +0000177 LandingPadInst *LPI = Invoke.getLandingPadInst();
178
Chris Lattner5eef6ad2009-08-27 03:51:50 +0000179 for (BasicBlock::iterator BBI = BB->begin(), E = BB->end(); BBI != E; ) {
180 Instruction *I = BBI++;
Bill Wendling55421f02011-08-14 08:01:36 +0000181
Bill Wendlingf3cae512012-01-31 00:56:53 +0000182 if (LandingPadInst *L = dyn_cast<LandingPadInst>(I)) {
183 unsigned NumClauses = LPI->getNumClauses();
184 L->reserveClauses(NumClauses);
185 for (unsigned i = 0; i != NumClauses; ++i)
186 L->addClause(LPI->getClause(i));
187 }
Bill Wendling55421f02011-08-14 08:01:36 +0000188
Chris Lattner5eef6ad2009-08-27 03:51:50 +0000189 // We only need to check for function calls: inlined invoke
190 // instructions require no special handling.
191 CallInst *CI = dyn_cast<CallInst>(I);
John McCallbd04b742011-05-27 18:34:38 +0000192
Chris Lattner5eef6ad2009-08-27 03:51:50 +0000193 // If this call cannot unwind, don't convert it to an invoke.
Manman Ren87a2adc2013-10-31 21:56:03 +0000194 // Inline asm calls cannot throw.
195 if (!CI || CI->doesNotThrow() || isa<InlineAsm>(CI->getCalledValue()))
Chris Lattner5eef6ad2009-08-27 03:51:50 +0000196 continue;
Bill Wendling518a2052012-01-31 01:05:20 +0000197
198 // Convert this function call into an invoke instruction. First, split the
199 // basic block.
Chris Lattner5eef6ad2009-08-27 03:51:50 +0000200 BasicBlock *Split = BB->splitBasicBlock(CI, CI->getName()+".noexc");
John McCallbd04b742011-05-27 18:34:38 +0000201
John McCall046c47e2011-05-28 07:45:59 +0000202 // Delete the unconditional branch inserted by splitBasicBlock
203 BB->getInstList().pop_back();
John McCallbd04b742011-05-27 18:34:38 +0000204
Bill Wendling621699d2012-01-31 01:14:49 +0000205 // Create the new invoke instruction.
John McCall046c47e2011-05-28 07:45:59 +0000206 ImmutableCallSite CS(CI);
207 SmallVector<Value*, 8> InvokeArgs(CS.arg_begin(), CS.arg_end());
Bill Wendlingce0c2292012-01-31 01:01:16 +0000208 InvokeInst *II = InvokeInst::Create(CI->getCalledValue(), Split,
Bill Wendling0c2d82b2012-01-31 01:22:03 +0000209 Invoke.getOuterResumeDest(),
Bill Wendlingce0c2292012-01-31 01:01:16 +0000210 InvokeArgs, CI->getName(), BB);
John McCall046c47e2011-05-28 07:45:59 +0000211 II->setCallingConv(CI->getCallingConv());
212 II->setAttributes(CI->getAttributes());
Chris Lattner5eef6ad2009-08-27 03:51:50 +0000213
John McCall046c47e2011-05-28 07:45:59 +0000214 // Make sure that anything using the call now uses the invoke! This also
215 // updates the CallGraph if present, because it uses a WeakVH.
216 CI->replaceAllUsesWith(II);
John McCallbd04b742011-05-27 18:34:38 +0000217
Bill Wendlingce0c2292012-01-31 01:01:16 +0000218 // Delete the original call
219 Split->getInstList().pop_front();
John McCall046c47e2011-05-28 07:45:59 +0000220
Bill Wendlingce0c2292012-01-31 01:01:16 +0000221 // Update any PHI nodes in the exceptional block to indicate that there is
222 // now a new entry in them.
John McCallbd04b742011-05-27 18:34:38 +0000223 Invoke.addIncomingPHIValuesFor(BB);
Mark Seabornd91fa222013-12-02 20:50:59 +0000224 return;
Chris Lattner5eef6ad2009-08-27 03:51:50 +0000225 }
226}
Chris Lattner5eef6ad2009-08-27 03:51:50 +0000227
Chris Lattner908d7952006-01-13 19:05:59 +0000228/// HandleInlinedInvoke - If we inlined an invoke site, we need to convert calls
Bill Wendling0aef16a2012-02-06 21:44:22 +0000229/// in the body of the inlined function into invokes.
Chris Lattner908d7952006-01-13 19:05:59 +0000230///
Nick Lewycky12a130b2009-02-03 04:34:40 +0000231/// II is the invoke instruction being inlined. FirstNewBlock is the first
Chris Lattner908d7952006-01-13 19:05:59 +0000232/// block of the inlined code (the last block is the end of the function),
233/// and InlineCodeInfo is information about the code that got inlined.
234static void HandleInlinedInvoke(InvokeInst *II, BasicBlock *FirstNewBlock,
Chris Lattner8900f3e2009-09-01 18:44:06 +0000235 ClonedCodeInfo &InlinedCodeInfo) {
Chris Lattner908d7952006-01-13 19:05:59 +0000236 BasicBlock *InvokeDest = II->getUnwindDest();
Chris Lattner908d7952006-01-13 19:05:59 +0000237
238 Function *Caller = FirstNewBlock->getParent();
Duncan Sands7c8fb1a2008-09-05 12:37:12 +0000239
Chris Lattner908d7952006-01-13 19:05:59 +0000240 // The inlined code is currently at the end of the function, scan from the
241 // start of the inlined code to its end, checking for stuff we need to
Bill Wendling173c71f2013-03-21 23:30:12 +0000242 // rewrite.
John McCallbd04b742011-05-27 18:34:38 +0000243 InvokeInliningInfo Invoke(II);
Bill Wendling173c71f2013-03-21 23:30:12 +0000244
Bill Wendling56f15bf2013-03-22 20:31:05 +0000245 // Get all of the inlined landing pad instructions.
246 SmallPtrSet<LandingPadInst*, 16> InlinedLPads;
247 for (Function::iterator I = FirstNewBlock, E = Caller->end(); I != E; ++I)
248 if (InvokeInst *II = dyn_cast<InvokeInst>(I->getTerminator()))
249 InlinedLPads.insert(II->getLandingPadInst());
250
Chris Lattner5eef6ad2009-08-27 03:51:50 +0000251 for (Function::iterator BB = FirstNewBlock, E = Caller->end(); BB != E; ++BB){
252 if (InlinedCodeInfo.ContainsCalls)
Mark Seabornd91fa222013-12-02 20:50:59 +0000253 HandleCallsInBlockInlinedThroughInvoke(BB, Invoke);
Duncan Sands7c8fb1a2008-09-05 12:37:12 +0000254
Bill Wendling173c71f2013-03-21 23:30:12 +0000255 // Forward any resumes that are remaining here.
Bill Wendling621699d2012-01-31 01:14:49 +0000256 if (ResumeInst *RI = dyn_cast<ResumeInst>(BB->getTerminator()))
Bill Wendling56f15bf2013-03-22 20:31:05 +0000257 Invoke.forwardResume(RI, InlinedLPads);
Chris Lattner908d7952006-01-13 19:05:59 +0000258 }
259
260 // Now that everything is happy, we have one final detail. The PHI nodes in
261 // the exception destination block still have entries due to the original
Bill Wendling173c71f2013-03-21 23:30:12 +0000262 // invoke instruction. Eliminate these entries (which might even delete the
Chris Lattner908d7952006-01-13 19:05:59 +0000263 // PHI node) now.
264 InvokeDest->removePredecessor(II->getParent());
265}
266
Chris Lattner5de3b8b2006-07-12 18:29:36 +0000267/// UpdateCallGraphAfterInlining - Once we have cloned code over from a callee
268/// into the caller, update the specified callgraph to reflect the changes we
269/// made. Note that it's possible that not all code was copied over, so only
Duncan Sands46911f12008-09-08 11:05:51 +0000270/// some edges of the callgraph may remain.
271static void UpdateCallGraphAfterInlining(CallSite CS,
Chris Lattner5de3b8b2006-07-12 18:29:36 +0000272 Function::iterator FirstNewBlock,
Rafael Espindola229e38f2010-10-13 01:36:30 +0000273 ValueToValueMapTy &VMap,
Chris Lattner2eee5d32010-04-22 23:37:35 +0000274 InlineFunctionInfo &IFI) {
275 CallGraph &CG = *IFI.CG;
Duncan Sands46911f12008-09-08 11:05:51 +0000276 const Function *Caller = CS.getInstruction()->getParent()->getParent();
277 const Function *Callee = CS.getCalledFunction();
Chris Lattner0841fb12006-01-14 20:07:50 +0000278 CallGraphNode *CalleeNode = CG[Callee];
279 CallGraphNode *CallerNode = CG[Caller];
Duncan Sands7c8fb1a2008-09-05 12:37:12 +0000280
Chris Lattner5de3b8b2006-07-12 18:29:36 +0000281 // Since we inlined some uninlined call sites in the callee into the caller,
Chris Lattner0841fb12006-01-14 20:07:50 +0000282 // add edges from the caller to all of the callees of the callee.
Gabor Greif5aa19222009-01-15 18:40:09 +0000283 CallGraphNode::iterator I = CalleeNode->begin(), E = CalleeNode->end();
284
285 // Consider the case where CalleeNode == CallerNode.
Gabor Greiff1abfdc2009-01-17 00:09:08 +0000286 CallGraphNode::CalledFunctionsVector CallCache;
Gabor Greif5aa19222009-01-15 18:40:09 +0000287 if (CalleeNode == CallerNode) {
288 CallCache.assign(I, E);
289 I = CallCache.begin();
290 E = CallCache.end();
291 }
292
293 for (; I != E; ++I) {
Chris Lattner063d0652009-09-01 06:31:31 +0000294 const Value *OrigCall = I->first;
Duncan Sands7c8fb1a2008-09-05 12:37:12 +0000295
Rafael Espindola229e38f2010-10-13 01:36:30 +0000296 ValueToValueMapTy::iterator VMI = VMap.find(OrigCall);
Chris Lattnerb3c64f72006-07-12 21:37:11 +0000297 // Only copy the edge if the call was inlined!
Devang Patelb8f11de2010-06-23 23:55:51 +0000298 if (VMI == VMap.end() || VMI->second == 0)
Chris Lattner5eef6ad2009-08-27 03:51:50 +0000299 continue;
300
301 // If the call was inlined, but then constant folded, there is no edge to
302 // add. Check for this case.
Chris Lattner016c00a2010-04-22 21:31:00 +0000303 Instruction *NewCall = dyn_cast<Instruction>(VMI->second);
304 if (NewCall == 0) continue;
Chris Lattnerc2432b92010-05-01 01:26:13 +0000305
306 // Remember that this call site got inlined for the client of
307 // InlineFunction.
308 IFI.InlinedCalls.push_back(NewCall);
309
Chris Lattner016c00a2010-04-22 21:31:00 +0000310 // It's possible that inlining the callsite will cause it to go from an
311 // indirect to a direct call by resolving a function pointer. If this
312 // happens, set the callee of the new call site to a more precise
313 // destination. This can also happen if the call graph node of the caller
314 // was just unnecessarily imprecise.
315 if (I->second->getFunction() == 0)
316 if (Function *F = CallSite(NewCall).getCalledFunction()) {
317 // Indirect call site resolved to direct call.
Gabor Greif7b0a5fd2010-07-27 15:02:37 +0000318 CallerNode->addCalledFunction(CallSite(NewCall), CG[F]);
319
Chris Lattner016c00a2010-04-22 21:31:00 +0000320 continue;
321 }
Gabor Greif7b0a5fd2010-07-27 15:02:37 +0000322
323 CallerNode->addCalledFunction(CallSite(NewCall), I->second);
Chris Lattner5de3b8b2006-07-12 18:29:36 +0000324 }
Chris Lattner5eef6ad2009-08-27 03:51:50 +0000325
Dale Johannesen0aeabdf2009-01-13 22:43:37 +0000326 // Update the call graph by deleting the edge from Callee to Caller. We must
327 // do this after the loop above in case Caller and Callee are the same.
328 CallerNode->removeCallEdgeFor(CS);
Chris Lattner0841fb12006-01-14 20:07:50 +0000329}
330
Chris Lattner0f114952010-12-20 08:10:40 +0000331/// HandleByValArgument - When inlining a call site that has a byval argument,
332/// we have to make the implicit memcpy explicit by adding it.
David Majnemer120f4a02013-11-03 12:22:13 +0000333static Value *HandleByValArgument(Value *Arg, Instruction *TheCall,
Chris Lattner00997442010-12-20 07:57:41 +0000334 const Function *CalledFunc,
335 InlineFunctionInfo &IFI,
336 unsigned ByValAlignment) {
David Majnemer120f4a02013-11-03 12:22:13 +0000337 Type *AggTy = cast<PointerType>(Arg->getType())->getElementType();
Chris Lattner0f114952010-12-20 08:10:40 +0000338
339 // If the called function is readonly, then it could not mutate the caller's
340 // copy of the byval'd memory. In this case, it is safe to elide the copy and
341 // temporary.
David Majnemer120f4a02013-11-03 12:22:13 +0000342 if (CalledFunc->onlyReadsMemory()) {
Chris Lattner0f114952010-12-20 08:10:40 +0000343 // If the byval argument has a specified alignment that is greater than the
344 // passed in pointer, then we either have to round up the input pointer or
345 // give up on this transformation.
346 if (ByValAlignment <= 1) // 0 = unspecified, 1 = no particular alignment.
David Majnemer120f4a02013-11-03 12:22:13 +0000347 return Arg;
Chris Lattner0f114952010-12-20 08:10:40 +0000348
Chris Lattner20fca482010-12-25 20:42:38 +0000349 // If the pointer is already known to be sufficiently aligned, or if we can
350 // round it up to a larger alignment, then we don't need a temporary.
David Majnemer120f4a02013-11-03 12:22:13 +0000351 if (getOrEnforceKnownAlignment(Arg, ByValAlignment,
Chris Lattner20fca482010-12-25 20:42:38 +0000352 IFI.TD) >= ByValAlignment)
David Majnemer120f4a02013-11-03 12:22:13 +0000353 return Arg;
Chris Lattner0f114952010-12-20 08:10:40 +0000354
Chris Lattner20fca482010-12-25 20:42:38 +0000355 // Otherwise, we have to make a memcpy to get a safe alignment. This is bad
356 // for code quality, but rarely happens and is required for correctness.
Chris Lattner0f114952010-12-20 08:10:40 +0000357 }
Chris Lattner00997442010-12-20 07:57:41 +0000358
David Majnemer120f4a02013-11-03 12:22:13 +0000359 LLVMContext &Context = Arg->getContext();
Chris Lattner00997442010-12-20 07:57:41 +0000360
Jay Foadb804a2b2011-07-12 14:06:48 +0000361 Type *VoidPtrTy = Type::getInt8PtrTy(Context);
Chris Lattner00997442010-12-20 07:57:41 +0000362
Micah Villmowcdfe20b2012-10-08 16:38:25 +0000363 // Create the alloca. If we have DataLayout, use nice alignment.
Chris Lattner00997442010-12-20 07:57:41 +0000364 unsigned Align = 1;
365 if (IFI.TD)
366 Align = IFI.TD->getPrefTypeAlignment(AggTy);
367
368 // If the byval had an alignment specified, we *must* use at least that
369 // alignment, as it is required by the byval argument (and uses of the
370 // pointer inside the callee).
371 Align = std::max(Align, ByValAlignment);
372
373 Function *Caller = TheCall->getParent()->getParent();
374
David Majnemer120f4a02013-11-03 12:22:13 +0000375 Value *NewAlloca = new AllocaInst(AggTy, 0, Align, Arg->getName(),
Chris Lattner00997442010-12-20 07:57:41 +0000376 &*Caller->begin()->begin());
377 // Emit a memcpy.
Jay Foadb804a2b2011-07-12 14:06:48 +0000378 Type *Tys[3] = {VoidPtrTy, VoidPtrTy, Type::getInt64Ty(Context)};
Chris Lattner00997442010-12-20 07:57:41 +0000379 Function *MemCpyFn = Intrinsic::getDeclaration(Caller->getParent(),
380 Intrinsic::memcpy,
Benjamin Kramere6e19332011-07-14 17:45:39 +0000381 Tys);
Chris Lattner00997442010-12-20 07:57:41 +0000382 Value *DestCast = new BitCastInst(NewAlloca, VoidPtrTy, "tmp", TheCall);
David Majnemer120f4a02013-11-03 12:22:13 +0000383 Value *SrcCast = new BitCastInst(Arg, VoidPtrTy, "tmp", TheCall);
Chris Lattner00997442010-12-20 07:57:41 +0000384
385 Value *Size;
386 if (IFI.TD == 0)
387 Size = ConstantExpr::getSizeOf(AggTy);
388 else
389 Size = ConstantInt::get(Type::getInt64Ty(Context),
390 IFI.TD->getTypeStoreSize(AggTy));
391
392 // Always generate a memcpy of alignment 1 here because we don't know
393 // the alignment of the src pointer. Other optimizations can infer
394 // better alignment.
395 Value *CallArgs[] = {
396 DestCast, SrcCast, Size,
397 ConstantInt::get(Type::getInt32Ty(Context), 1),
398 ConstantInt::getFalse(Context) // isVolatile
399 };
Jay Foad5bd375a2011-07-15 08:37:34 +0000400 IRBuilder<>(TheCall).CreateCall(MemCpyFn, CallArgs);
Chris Lattner00997442010-12-20 07:57:41 +0000401
402 // Uses of the argument in the function should use our new alloca
403 // instead.
404 return NewAlloca;
405}
406
Nick Lewyckya68ec832011-05-22 05:22:10 +0000407// isUsedByLifetimeMarker - Check whether this Value is used by a lifetime
408// intrinsic.
409static bool isUsedByLifetimeMarker(Value *V) {
410 for (Value::use_iterator UI = V->use_begin(), UE = V->use_end(); UI != UE;
411 ++UI) {
412 if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(*UI)) {
413 switch (II->getIntrinsicID()) {
414 default: break;
415 case Intrinsic::lifetime_start:
416 case Intrinsic::lifetime_end:
417 return true;
418 }
419 }
420 }
421 return false;
422}
423
424// hasLifetimeMarkers - Check whether the given alloca already has
425// lifetime.start or lifetime.end intrinsics.
426static bool hasLifetimeMarkers(AllocaInst *AI) {
Chris Lattner229907c2011-07-18 04:54:35 +0000427 Type *Int8PtrTy = Type::getInt8PtrTy(AI->getType()->getContext());
Nick Lewyckya68ec832011-05-22 05:22:10 +0000428 if (AI->getType() == Int8PtrTy)
429 return isUsedByLifetimeMarker(AI);
430
Nick Lewycky9711b5c2011-06-14 00:59:24 +0000431 // Do a scan to find all the casts to i8*.
Nick Lewyckya68ec832011-05-22 05:22:10 +0000432 for (Value::use_iterator I = AI->use_begin(), E = AI->use_end(); I != E;
433 ++I) {
434 if (I->getType() != Int8PtrTy) continue;
Nick Lewycky9711b5c2011-06-14 00:59:24 +0000435 if (I->stripPointerCasts() != AI) continue;
Nick Lewyckya68ec832011-05-22 05:22:10 +0000436 if (isUsedByLifetimeMarker(*I))
437 return true;
438 }
439 return false;
440}
441
Eric Christopherf16bee82012-03-26 19:09:38 +0000442/// updateInlinedAtInfo - Helper function used by fixupLineNumbers to
443/// recursively update InlinedAtEntry of a DebugLoc.
Devang Patel35797402011-07-08 18:01:31 +0000444static DebugLoc updateInlinedAtInfo(const DebugLoc &DL,
445 const DebugLoc &InlinedAtDL,
446 LLVMContext &Ctx) {
447 if (MDNode *IA = DL.getInlinedAt(Ctx)) {
448 DebugLoc NewInlinedAtDL
449 = updateInlinedAtInfo(DebugLoc::getFromDILocation(IA), InlinedAtDL, Ctx);
450 return DebugLoc::get(DL.getLine(), DL.getCol(), DL.getScope(Ctx),
451 NewInlinedAtDL.getAsMDNode(Ctx));
452 }
Eric Christopherf16bee82012-03-26 19:09:38 +0000453
Devang Patel35797402011-07-08 18:01:31 +0000454 return DebugLoc::get(DL.getLine(), DL.getCol(), DL.getScope(Ctx),
455 InlinedAtDL.getAsMDNode(Ctx));
456}
457
Devang Patel35797402011-07-08 18:01:31 +0000458/// fixupLineNumbers - Update inlined instructions' line numbers to
459/// to encode location where these instructions are inlined.
460static void fixupLineNumbers(Function *Fn, Function::iterator FI,
Eric Christopher2b40fdf2012-03-26 19:09:40 +0000461 Instruction *TheCall) {
Devang Patel35797402011-07-08 18:01:31 +0000462 DebugLoc TheCallDL = TheCall->getDebugLoc();
463 if (TheCallDL.isUnknown())
464 return;
465
466 for (; FI != Fn->end(); ++FI) {
467 for (BasicBlock::iterator BI = FI->begin(), BE = FI->end();
468 BI != BE; ++BI) {
469 DebugLoc DL = BI->getDebugLoc();
Devang Patelbb23a4a2011-08-10 21:50:54 +0000470 if (!DL.isUnknown()) {
Devang Patel35797402011-07-08 18:01:31 +0000471 BI->setDebugLoc(updateInlinedAtInfo(DL, TheCallDL, BI->getContext()));
Devang Patelbb23a4a2011-08-10 21:50:54 +0000472 if (DbgValueInst *DVI = dyn_cast<DbgValueInst>(BI)) {
473 LLVMContext &Ctx = BI->getContext();
474 MDNode *InlinedAt = BI->getDebugLoc().getInlinedAt(Ctx);
475 DVI->setOperand(2, createInlinedVariable(DVI->getVariable(),
476 InlinedAt, Ctx));
477 }
478 }
Devang Patel35797402011-07-08 18:01:31 +0000479 }
480 }
481}
482
Bill Wendlingce0c2292012-01-31 01:01:16 +0000483/// InlineFunction - This function inlines the called function into the basic
484/// block of the caller. This returns false if it is not possible to inline
485/// this call. The program is still in a well defined state if this occurs
486/// though.
487///
488/// Note that this only does one level of inlining. For example, if the
489/// instruction 'call B' is inlined, and 'B' calls 'C', then the call to 'C' now
490/// exists in the instruction stream. Similarly this will inline a recursive
491/// function by one level.
Eric Christopherf16bee82012-03-26 19:09:38 +0000492bool llvm::InlineFunction(CallSite CS, InlineFunctionInfo &IFI,
493 bool InsertLifetime) {
Chris Lattner0cc265e2003-08-24 06:59:16 +0000494 Instruction *TheCall = CS.getInstruction();
495 assert(TheCall->getParent() && TheCall->getParent()->getParent() &&
496 "Instruction not in function!");
Chris Lattner530d4bf2003-05-29 15:11:31 +0000497
Chris Lattner4ba01ec2010-04-22 23:07:58 +0000498 // If IFI has any state in it, zap it before we fill it in.
499 IFI.reset();
500
Chris Lattner0cc265e2003-08-24 06:59:16 +0000501 const Function *CalledFunc = CS.getCalledFunction();
Chris Lattner530d4bf2003-05-29 15:11:31 +0000502 if (CalledFunc == 0 || // Can't inline external function or indirect
Reid Spencer5301e7c2007-01-30 20:08:39 +0000503 CalledFunc->isDeclaration() || // call, or call to a vararg function!
Eric Christopher1d385382010-03-24 23:35:21 +0000504 CalledFunc->getFunctionType()->isVarArg()) return false;
Chris Lattner530d4bf2003-05-29 15:11:31 +0000505
Chris Lattnerfeb129e2009-02-12 07:06:42 +0000506 // If the call to the callee is not a tail call, we must clear the 'tail'
Chris Lattner9f3dced2005-05-06 06:47:52 +0000507 // flags on any calls that we inline.
508 bool MustClearTailCallFlags =
Chris Lattnerfeb129e2009-02-12 07:06:42 +0000509 !(isa<CallInst>(TheCall) && cast<CallInst>(TheCall)->isTailCall());
Chris Lattner9f3dced2005-05-06 06:47:52 +0000510
Duncan Sandsaa31b922007-12-19 21:13:37 +0000511 // If the call to the callee cannot throw, set the 'nounwind' flag on any
512 // calls that we inline.
513 bool MarkNoUnwind = CS.doesNotThrow();
514
Chris Lattner0cc265e2003-08-24 06:59:16 +0000515 BasicBlock *OrigBB = TheCall->getParent();
Chris Lattner530d4bf2003-05-29 15:11:31 +0000516 Function *Caller = OrigBB->getParent();
517
Gordon Henriksenb969c592007-12-25 03:10:07 +0000518 // GC poses two hazards to inlining, which only occur when the callee has GC:
519 // 1. If the caller has no GC, then the callee's GC must be propagated to the
520 // caller.
521 // 2. If the caller has a differing GC, it is invalid to inline.
Gordon Henriksend930f912008-08-17 18:44:35 +0000522 if (CalledFunc->hasGC()) {
523 if (!Caller->hasGC())
524 Caller->setGC(CalledFunc->getGC());
525 else if (CalledFunc->getGC() != Caller->getGC())
Gordon Henriksenb969c592007-12-25 03:10:07 +0000526 return false;
527 }
Duncan Sands7c8fb1a2008-09-05 12:37:12 +0000528
Benjamin Kramer4d2b8712011-12-02 18:37:31 +0000529 // Get the personality function from the callee if it contains a landing pad.
530 Value *CalleePersonality = 0;
531 for (Function::const_iterator I = CalledFunc->begin(), E = CalledFunc->end();
532 I != E; ++I)
533 if (const InvokeInst *II = dyn_cast<InvokeInst>(I->getTerminator())) {
534 const BasicBlock *BB = II->getUnwindDest();
Bill Wendlingf3cae512012-01-31 00:56:53 +0000535 const LandingPadInst *LP = BB->getLandingPadInst();
536 CalleePersonality = LP->getPersonalityFn();
Benjamin Kramer4d2b8712011-12-02 18:37:31 +0000537 break;
538 }
539
Bill Wendling55421f02011-08-14 08:01:36 +0000540 // Find the personality function used by the landing pads of the caller. If it
541 // exists, then check to see that it matches the personality function used in
542 // the callee.
Bill Wendlingce0c2292012-01-31 01:01:16 +0000543 if (CalleePersonality) {
Benjamin Kramer4d2b8712011-12-02 18:37:31 +0000544 for (Function::const_iterator I = Caller->begin(), E = Caller->end();
545 I != E; ++I)
546 if (const InvokeInst *II = dyn_cast<InvokeInst>(I->getTerminator())) {
547 const BasicBlock *BB = II->getUnwindDest();
Bill Wendlingf3cae512012-01-31 00:56:53 +0000548 const LandingPadInst *LP = BB->getLandingPadInst();
Bill Wendling55421f02011-08-14 08:01:36 +0000549
Benjamin Kramer4d2b8712011-12-02 18:37:31 +0000550 // If the personality functions match, then we can perform the
551 // inlining. Otherwise, we can't inline.
552 // TODO: This isn't 100% true. Some personality functions are proper
553 // supersets of others and can be used in place of the other.
554 if (LP->getPersonalityFn() != CalleePersonality)
555 return false;
Bill Wendling55421f02011-08-14 08:01:36 +0000556
Benjamin Kramer4d2b8712011-12-02 18:37:31 +0000557 break;
558 }
Bill Wendlingce0c2292012-01-31 01:01:16 +0000559 }
Bill Wendling55421f02011-08-14 08:01:36 +0000560
Chris Lattner9fc977e2004-02-04 01:41:09 +0000561 // Get an iterator to the last basic block in the function, which will have
562 // the new function inlined after it.
Chris Lattner9fc977e2004-02-04 01:41:09 +0000563 Function::iterator LastBlock = &Caller->back();
564
Chris Lattner18ef3fd2004-02-04 02:51:48 +0000565 // Make sure to capture all of the return instructions from the cloned
Chris Lattner530d4bf2003-05-29 15:11:31 +0000566 // function.
Chris Lattnerd84dbb32009-08-27 04:02:30 +0000567 SmallVector<ReturnInst*, 8> Returns;
Chris Lattner908d7952006-01-13 19:05:59 +0000568 ClonedCodeInfo InlinedFunctionInfo;
Dale Johannesen845e5822009-03-04 02:09:48 +0000569 Function::iterator FirstNewBlock;
Duncan Sandsaa31b922007-12-19 21:13:37 +0000570
Devang Patelb8f11de2010-06-23 23:55:51 +0000571 { // Scope to destroy VMap after cloning.
Rafael Espindola229e38f2010-10-13 01:36:30 +0000572 ValueToValueMapTy VMap;
Chris Lattnerbe853d72006-05-27 01:28:04 +0000573
Dan Gohman3ada1e12008-06-20 17:11:32 +0000574 assert(CalledFunc->arg_size() == CS.arg_size() &&
Chris Lattner18ef3fd2004-02-04 02:51:48 +0000575 "No varargs calls can be inlined!");
Duncan Sands7c8fb1a2008-09-05 12:37:12 +0000576
Chris Lattner908117b2008-01-11 06:09:30 +0000577 // Calculate the vector of arguments to pass into the function cloner, which
578 // matches up the formal to the actual argument values.
Chris Lattner18ef3fd2004-02-04 02:51:48 +0000579 CallSite::arg_iterator AI = CS.arg_begin();
Chris Lattner908117b2008-01-11 06:09:30 +0000580 unsigned ArgNo = 0;
Chris Lattner531f9e92005-03-15 04:54:21 +0000581 for (Function::const_arg_iterator I = CalledFunc->arg_begin(),
Chris Lattner908117b2008-01-11 06:09:30 +0000582 E = CalledFunc->arg_end(); I != E; ++I, ++AI, ++ArgNo) {
583 Value *ActualArg = *AI;
Duncan Sands7c8fb1a2008-09-05 12:37:12 +0000584
Duncan Sands053c9872008-01-27 18:12:58 +0000585 // When byval arguments actually inlined, we need to make the copy implied
586 // by them explicit. However, we don't do this if the callee is readonly
587 // or readnone, because the copy would be unneeded: the callee doesn't
588 // modify the struct.
Nick Lewycky612d70b2011-11-20 19:09:04 +0000589 if (CS.isByValArgument(ArgNo)) {
David Majnemer120f4a02013-11-03 12:22:13 +0000590 ActualArg = HandleByValArgument(ActualArg, TheCall, CalledFunc, IFI,
Chris Lattner00997442010-12-20 07:57:41 +0000591 CalledFunc->getParamAlignment(ArgNo+1));
592
Duncan Sands4c904fa2010-05-31 21:00:26 +0000593 // Calls that we inline may use the new alloca, so we need to clear
Chris Lattner00997442010-12-20 07:57:41 +0000594 // their 'tail' flags if HandleByValArgument introduced a new alloca and
595 // the callee has calls.
596 MustClearTailCallFlags |= ActualArg != *AI;
Chris Lattner908117b2008-01-11 06:09:30 +0000597 }
Duncan Sands7c8fb1a2008-09-05 12:37:12 +0000598
Devang Patelb8f11de2010-06-23 23:55:51 +0000599 VMap[I] = ActualArg;
Chris Lattner908117b2008-01-11 06:09:30 +0000600 }
Misha Brukmanb1c93172005-04-21 23:48:37 +0000601
Chris Lattnerbe853d72006-05-27 01:28:04 +0000602 // We want the inliner to prune the code as it copies. We would LOVE to
603 // have no dead or constant instructions leftover after inlining occurs
604 // (which can happen, e.g., because an argument was constant), but we'll be
605 // happy with whatever the cloner can do.
Dan Gohmanca26f792010-08-26 15:41:53 +0000606 CloneAndPruneFunctionInto(Caller, CalledFunc, VMap,
607 /*ModuleLevelChanges=*/false, Returns, ".i",
Chris Lattner4ba01ec2010-04-22 23:07:58 +0000608 &InlinedFunctionInfo, IFI.TD, TheCall);
Duncan Sands7c8fb1a2008-09-05 12:37:12 +0000609
Chris Lattner5de3b8b2006-07-12 18:29:36 +0000610 // Remember the first block that is newly cloned over.
611 FirstNewBlock = LastBlock; ++FirstNewBlock;
Duncan Sands7c8fb1a2008-09-05 12:37:12 +0000612
Chris Lattner5de3b8b2006-07-12 18:29:36 +0000613 // Update the callgraph if requested.
Chris Lattner4ba01ec2010-04-22 23:07:58 +0000614 if (IFI.CG)
Devang Patelb8f11de2010-06-23 23:55:51 +0000615 UpdateCallGraphAfterInlining(CS, FirstNewBlock, VMap, IFI);
Devang Patel35797402011-07-08 18:01:31 +0000616
617 // Update inlined instructions' line number information.
618 fixupLineNumbers(Caller, FirstNewBlock, TheCall);
Misha Brukmanb1c93172005-04-21 23:48:37 +0000619 }
Duncan Sands7c8fb1a2008-09-05 12:37:12 +0000620
Chris Lattner530d4bf2003-05-29 15:11:31 +0000621 // If there are any alloca instructions in the block that used to be the entry
622 // block for the callee, move them to the entry block of the caller. First
623 // calculate which instruction they should be inserted before. We insert the
624 // instructions at the end of the current alloca list.
Chris Lattner257492c2006-01-13 18:16:48 +0000625 {
Chris Lattner0cc265e2003-08-24 06:59:16 +0000626 BasicBlock::iterator InsertPoint = Caller->begin()->begin();
Chris Lattner18ef3fd2004-02-04 02:51:48 +0000627 for (BasicBlock::iterator I = FirstNewBlock->begin(),
Chris Lattner5eef6ad2009-08-27 03:51:50 +0000628 E = FirstNewBlock->end(); I != E; ) {
629 AllocaInst *AI = dyn_cast<AllocaInst>(I++);
630 if (AI == 0) continue;
631
632 // If the alloca is now dead, remove it. This often occurs due to code
633 // specialization.
634 if (AI->use_empty()) {
635 AI->eraseFromParent();
636 continue;
Chris Lattner6ef6d062006-09-13 19:23:57 +0000637 }
Chris Lattner5eef6ad2009-08-27 03:51:50 +0000638
639 if (!isa<Constant>(AI->getArraySize()))
640 continue;
641
Chris Lattnercd3af962010-12-06 07:43:04 +0000642 // Keep track of the static allocas that we inline into the caller.
Chris Lattner4ba01ec2010-04-22 23:07:58 +0000643 IFI.StaticAllocas.push_back(AI);
Chris Lattnerb1cba3f2009-08-27 04:20:52 +0000644
Chris Lattner5eef6ad2009-08-27 03:51:50 +0000645 // Scan for the block of allocas that we can move over, and move them
646 // all at once.
647 while (isa<AllocaInst>(I) &&
Chris Lattnerb1cba3f2009-08-27 04:20:52 +0000648 isa<Constant>(cast<AllocaInst>(I)->getArraySize())) {
Chris Lattner4ba01ec2010-04-22 23:07:58 +0000649 IFI.StaticAllocas.push_back(cast<AllocaInst>(I));
Chris Lattner5eef6ad2009-08-27 03:51:50 +0000650 ++I;
Chris Lattnerb1cba3f2009-08-27 04:20:52 +0000651 }
Chris Lattner5eef6ad2009-08-27 03:51:50 +0000652
653 // Transfer all of the allocas over in a block. Using splice means
654 // that the instructions aren't removed from the symbol table, then
655 // reinserted.
656 Caller->getEntryBlock().getInstList().splice(InsertPoint,
657 FirstNewBlock->getInstList(),
658 AI, I);
659 }
Chris Lattner0cc265e2003-08-24 06:59:16 +0000660 }
Chris Lattner530d4bf2003-05-29 15:11:31 +0000661
Nick Lewyckya68ec832011-05-22 05:22:10 +0000662 // Leave lifetime markers for the static alloca's, scoping them to the
663 // function we just inlined.
Chad Rosier07d37bc2012-02-25 02:56:01 +0000664 if (InsertLifetime && !IFI.StaticAllocas.empty()) {
Nick Lewyckya68ec832011-05-22 05:22:10 +0000665 IRBuilder<> builder(FirstNewBlock->begin());
666 for (unsigned ai = 0, ae = IFI.StaticAllocas.size(); ai != ae; ++ai) {
667 AllocaInst *AI = IFI.StaticAllocas[ai];
668
669 // If the alloca is already scoped to something smaller than the whole
670 // function then there's no need to add redundant, less accurate markers.
671 if (hasLifetimeMarkers(AI))
672 continue;
673
Alexey Samsonovcfd662f2012-11-13 07:15:32 +0000674 // Try to determine the size of the allocation.
675 ConstantInt *AllocaSize = 0;
676 if (ConstantInt *AIArraySize =
677 dyn_cast<ConstantInt>(AI->getArraySize())) {
678 if (IFI.TD) {
679 Type *AllocaType = AI->getAllocatedType();
680 uint64_t AllocaTypeSize = IFI.TD->getTypeAllocSize(AllocaType);
681 uint64_t AllocaArraySize = AIArraySize->getLimitedValue();
682 assert(AllocaArraySize > 0 && "array size of AllocaInst is zero");
683 // Check that array size doesn't saturate uint64_t and doesn't
684 // overflow when it's multiplied by type size.
685 if (AllocaArraySize != ~0ULL &&
686 UINT64_MAX / AllocaArraySize >= AllocaTypeSize) {
687 AllocaSize = ConstantInt::get(Type::getInt64Ty(AI->getContext()),
688 AllocaArraySize * AllocaTypeSize);
689 }
690 }
691 }
692
693 builder.CreateLifetimeStart(AI, AllocaSize);
Nick Lewyckya68ec832011-05-22 05:22:10 +0000694 for (unsigned ri = 0, re = Returns.size(); ri != re; ++ri) {
695 IRBuilder<> builder(Returns[ri]);
Alexey Samsonovcfd662f2012-11-13 07:15:32 +0000696 builder.CreateLifetimeEnd(AI, AllocaSize);
Nick Lewyckya68ec832011-05-22 05:22:10 +0000697 }
698 }
699 }
700
Chris Lattner2be06072006-01-13 19:34:14 +0000701 // If the inlined code contained dynamic alloca instructions, wrap the inlined
702 // code with llvm.stacksave/llvm.stackrestore intrinsics.
703 if (InlinedFunctionInfo.ContainsDynamicAllocas) {
704 Module *M = Caller->getParent();
Chris Lattner2be06072006-01-13 19:34:14 +0000705 // Get the two intrinsics we care about.
Chris Lattner88b36f12009-10-17 05:39:39 +0000706 Function *StackSave = Intrinsic::getDeclaration(M, Intrinsic::stacksave);
707 Function *StackRestore=Intrinsic::getDeclaration(M,Intrinsic::stackrestore);
Chris Lattner5de3b8b2006-07-12 18:29:36 +0000708
Chris Lattner2be06072006-01-13 19:34:14 +0000709 // Insert the llvm.stacksave.
John McCall5af84522011-06-14 02:51:53 +0000710 CallInst *SavedPtr = IRBuilder<>(FirstNewBlock, FirstNewBlock->begin())
711 .CreateCall(StackSave, "savedstack");
Duncan Sands7c8fb1a2008-09-05 12:37:12 +0000712
Chris Lattner2be06072006-01-13 19:34:14 +0000713 // Insert a call to llvm.stackrestore before any return instructions in the
714 // inlined function.
Chris Lattner5de3b8b2006-07-12 18:29:36 +0000715 for (unsigned i = 0, e = Returns.size(); i != e; ++i) {
John McCall5af84522011-06-14 02:51:53 +0000716 IRBuilder<>(Returns[i]).CreateCall(StackRestore, SavedPtr);
Chris Lattner5de3b8b2006-07-12 18:29:36 +0000717 }
Chris Lattner2be06072006-01-13 19:34:14 +0000718 }
719
Duncan Sands7c8fb1a2008-09-05 12:37:12 +0000720 // If we are inlining tail call instruction through a call site that isn't
Chris Lattnere24f79a2006-01-13 19:18:11 +0000721 // marked 'tail', we must remove the tail marker for any calls in the inlined
Duncan Sandsaa31b922007-12-19 21:13:37 +0000722 // code. Also, calls inlined through a 'nounwind' call site should be marked
723 // 'nounwind'.
724 if (InlinedFunctionInfo.ContainsCalls &&
725 (MustClearTailCallFlags || MarkNoUnwind)) {
Chris Lattner9f3dced2005-05-06 06:47:52 +0000726 for (Function::iterator BB = FirstNewBlock, E = Caller->end();
727 BB != E; ++BB)
728 for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E; ++I)
Duncan Sandsaa31b922007-12-19 21:13:37 +0000729 if (CallInst *CI = dyn_cast<CallInst>(I)) {
730 if (MustClearTailCallFlags)
731 CI->setTailCall(false);
732 if (MarkNoUnwind)
733 CI->setDoesNotThrow();
734 }
Chris Lattner9f3dced2005-05-06 06:47:52 +0000735 }
736
Chris Lattner18ef3fd2004-02-04 02:51:48 +0000737 // If we are inlining for an invoke instruction, we must make sure to rewrite
Bill Wendling0aef16a2012-02-06 21:44:22 +0000738 // any call instructions into invoke instructions.
Chris Lattner908d7952006-01-13 19:05:59 +0000739 if (InvokeInst *II = dyn_cast<InvokeInst>(TheCall))
Chris Lattner8900f3e2009-09-01 18:44:06 +0000740 HandleInlinedInvoke(II, FirstNewBlock, InlinedFunctionInfo);
Chris Lattner18ef3fd2004-02-04 02:51:48 +0000741
Chris Lattner0fa8c7c2004-02-04 04:17:06 +0000742 // If we cloned in _exactly one_ basic block, and if that block ends in a
743 // return instruction, we splice the body of the inlined callee directly into
744 // the calling basic block.
745 if (Returns.size() == 1 && std::distance(FirstNewBlock, Caller->end()) == 1) {
746 // Move all of the instructions right before the call.
747 OrigBB->getInstList().splice(TheCall, FirstNewBlock->getInstList(),
748 FirstNewBlock->begin(), FirstNewBlock->end());
749 // Remove the cloned basic block.
750 Caller->getBasicBlockList().pop_back();
Misha Brukmanb1c93172005-04-21 23:48:37 +0000751
Chris Lattner0fa8c7c2004-02-04 04:17:06 +0000752 // If the call site was an invoke instruction, add a branch to the normal
753 // destination.
Adrian Prantl15db52b2013-04-23 19:56:03 +0000754 if (InvokeInst *II = dyn_cast<InvokeInst>(TheCall)) {
755 BranchInst *NewBr = BranchInst::Create(II->getNormalDest(), TheCall);
756 NewBr->setDebugLoc(Returns[0]->getDebugLoc());
757 }
Chris Lattner0fa8c7c2004-02-04 04:17:06 +0000758
759 // If the return instruction returned a value, replace uses of the call with
760 // uses of the returned value.
Devang Patel841322b2008-03-04 21:15:15 +0000761 if (!TheCall->use_empty()) {
762 ReturnInst *R = Returns[0];
Eli Friedman36b90262009-05-08 00:22:04 +0000763 if (TheCall == R->getReturnValue())
Owen Andersonb292b8c2009-07-30 23:03:37 +0000764 TheCall->replaceAllUsesWith(UndefValue::get(TheCall->getType()));
Eli Friedman36b90262009-05-08 00:22:04 +0000765 else
766 TheCall->replaceAllUsesWith(R->getReturnValue());
Devang Patel841322b2008-03-04 21:15:15 +0000767 }
Chris Lattner0fa8c7c2004-02-04 04:17:06 +0000768 // Since we are now done with the Call/Invoke, we can delete it.
Dan Gohman158ff2c2008-06-21 22:08:46 +0000769 TheCall->eraseFromParent();
Chris Lattner0fa8c7c2004-02-04 04:17:06 +0000770
771 // Since we are now done with the return instruction, delete it also.
Dan Gohman158ff2c2008-06-21 22:08:46 +0000772 Returns[0]->eraseFromParent();
Chris Lattner0fa8c7c2004-02-04 04:17:06 +0000773
774 // We are now done with the inlining.
775 return true;
776 }
777
778 // Otherwise, we have the normal case, of more than one block to inline or
779 // multiple return sites.
780
Chris Lattner18ef3fd2004-02-04 02:51:48 +0000781 // We want to clone the entire callee function into the hole between the
782 // "starter" and "ender" blocks. How we accomplish this depends on whether
783 // this is an invoke instruction or a call instruction.
784 BasicBlock *AfterCallBB;
Adrian Prantl15db52b2013-04-23 19:56:03 +0000785 BranchInst *CreatedBranchToNormalDest = NULL;
Chris Lattner18ef3fd2004-02-04 02:51:48 +0000786 if (InvokeInst *II = dyn_cast<InvokeInst>(TheCall)) {
Misha Brukmanb1c93172005-04-21 23:48:37 +0000787
Chris Lattner18ef3fd2004-02-04 02:51:48 +0000788 // Add an unconditional branch to make this look like the CallInst case...
Adrian Prantl15db52b2013-04-23 19:56:03 +0000789 CreatedBranchToNormalDest = BranchInst::Create(II->getNormalDest(), TheCall);
Misha Brukmanb1c93172005-04-21 23:48:37 +0000790
Chris Lattner18ef3fd2004-02-04 02:51:48 +0000791 // Split the basic block. This guarantees that no PHI nodes will have to be
792 // updated due to new incoming edges, and make the invoke case more
793 // symmetric to the call case.
Adrian Prantl15db52b2013-04-23 19:56:03 +0000794 AfterCallBB = OrigBB->splitBasicBlock(CreatedBranchToNormalDest,
Chris Lattnerffefea02004-12-11 16:59:54 +0000795 CalledFunc->getName()+".exit");
Misha Brukmanb1c93172005-04-21 23:48:37 +0000796
Chris Lattner18ef3fd2004-02-04 02:51:48 +0000797 } else { // It's a call
Chris Lattner0fa8c7c2004-02-04 04:17:06 +0000798 // If this is a call instruction, we need to split the basic block that
799 // the call lives in.
Chris Lattner18ef3fd2004-02-04 02:51:48 +0000800 //
801 AfterCallBB = OrigBB->splitBasicBlock(TheCall,
Chris Lattnerffefea02004-12-11 16:59:54 +0000802 CalledFunc->getName()+".exit");
Chris Lattner18ef3fd2004-02-04 02:51:48 +0000803 }
804
Chris Lattner0fa8c7c2004-02-04 04:17:06 +0000805 // Change the branch that used to go to AfterCallBB to branch to the first
806 // basic block of the inlined function.
807 //
808 TerminatorInst *Br = OrigBB->getTerminator();
Misha Brukmanb1c93172005-04-21 23:48:37 +0000809 assert(Br && Br->getOpcode() == Instruction::Br &&
Chris Lattner0fa8c7c2004-02-04 04:17:06 +0000810 "splitBasicBlock broken!");
811 Br->setOperand(0, FirstNewBlock);
812
813
814 // Now that the function is correct, make it a little bit nicer. In
815 // particular, move the basic blocks inserted from the end of the function
816 // into the space made by splitting the source basic block.
Chris Lattner0fa8c7c2004-02-04 04:17:06 +0000817 Caller->getBasicBlockList().splice(AfterCallBB, Caller->getBasicBlockList(),
818 FirstNewBlock, Caller->end());
819
Chris Lattner18ef3fd2004-02-04 02:51:48 +0000820 // Handle all of the return instructions that we just cloned in, and eliminate
821 // any users of the original call/invoke instruction.
Chris Lattner229907c2011-07-18 04:54:35 +0000822 Type *RTy = CalledFunc->getReturnType();
Dan Gohman3b18fd72008-06-20 01:03:44 +0000823
Duncan Sands9d9a4e22010-11-17 11:16:23 +0000824 PHINode *PHI = 0;
Dan Gohmanfa1211f2008-07-23 00:34:11 +0000825 if (Returns.size() > 1) {
Chris Lattner18ef3fd2004-02-04 02:51:48 +0000826 // The PHI node should go at the front of the new basic block to merge all
827 // possible incoming values.
Chris Lattner18ef3fd2004-02-04 02:51:48 +0000828 if (!TheCall->use_empty()) {
Jay Foad52131342011-03-30 11:28:46 +0000829 PHI = PHINode::Create(RTy, Returns.size(), TheCall->getName(),
Dan Gohmanfa1211f2008-07-23 00:34:11 +0000830 AfterCallBB->begin());
831 // Anything that used the result of the function call should now use the
832 // PHI node as their operand.
Duncan Sands7c8fb1a2008-09-05 12:37:12 +0000833 TheCall->replaceAllUsesWith(PHI);
Chris Lattner18ef3fd2004-02-04 02:51:48 +0000834 }
Misha Brukmanb1c93172005-04-21 23:48:37 +0000835
Gabor Greif5aa19222009-01-15 18:40:09 +0000836 // Loop over all of the return instructions adding entries to the PHI node
837 // as appropriate.
Dan Gohmanfa1211f2008-07-23 00:34:11 +0000838 if (PHI) {
839 for (unsigned i = 0, e = Returns.size(); i != e; ++i) {
840 ReturnInst *RI = Returns[i];
841 assert(RI->getReturnValue()->getType() == PHI->getType() &&
842 "Ret value not consistent in function!");
843 PHI->addIncoming(RI->getReturnValue(), RI->getParent());
Devang Patel780b3ca62008-03-07 20:06:16 +0000844 }
845 }
846
Chris Lattnerc6b3b252009-10-27 05:39:41 +0000847
Gabor Greif8c573f72009-01-16 23:08:50 +0000848 // Add a branch to the merge points and remove return instructions.
Richard Trieu624c2eb2013-04-30 22:45:10 +0000849 DebugLoc Loc;
Chris Lattner18ef3fd2004-02-04 02:51:48 +0000850 for (unsigned i = 0, e = Returns.size(); i != e; ++i) {
Richard Trieu624c2eb2013-04-30 22:45:10 +0000851 ReturnInst *RI = Returns[i];
Adrian Prantl09416382013-04-30 17:08:16 +0000852 BranchInst* BI = BranchInst::Create(AfterCallBB, RI);
Richard Trieu624c2eb2013-04-30 22:45:10 +0000853 Loc = RI->getDebugLoc();
854 BI->setDebugLoc(Loc);
Devang Patel64d0f072008-03-10 18:34:00 +0000855 RI->eraseFromParent();
Chris Lattner18ef3fd2004-02-04 02:51:48 +0000856 }
Adrian Prantl09416382013-04-30 17:08:16 +0000857 // We need to set the debug location to *somewhere* inside the
Adrian Prantl8beccf92013-04-30 17:33:32 +0000858 // inlined function. The line number may be nonsensical, but the
Adrian Prantl09416382013-04-30 17:08:16 +0000859 // instruction will at least be associated with the right
860 // function.
861 if (CreatedBranchToNormalDest)
Richard Trieu624c2eb2013-04-30 22:45:10 +0000862 CreatedBranchToNormalDest->setDebugLoc(Loc);
Devang Patel64d0f072008-03-10 18:34:00 +0000863 } else if (!Returns.empty()) {
864 // Otherwise, if there is exactly one return value, just replace anything
865 // using the return value of the call with the computed value.
Eli Friedman36b90262009-05-08 00:22:04 +0000866 if (!TheCall->use_empty()) {
867 if (TheCall == Returns[0]->getReturnValue())
Owen Andersonb292b8c2009-07-30 23:03:37 +0000868 TheCall->replaceAllUsesWith(UndefValue::get(TheCall->getType()));
Eli Friedman36b90262009-05-08 00:22:04 +0000869 else
870 TheCall->replaceAllUsesWith(Returns[0]->getReturnValue());
871 }
Duncan Sands7c8fb1a2008-09-05 12:37:12 +0000872
Jay Foad61ea0e42011-06-23 09:09:15 +0000873 // Update PHI nodes that use the ReturnBB to use the AfterCallBB.
874 BasicBlock *ReturnBB = Returns[0]->getParent();
875 ReturnBB->replaceAllUsesWith(AfterCallBB);
876
Devang Patel64d0f072008-03-10 18:34:00 +0000877 // Splice the code from the return block into the block that it will return
878 // to, which contains the code that was after the call.
Devang Patel64d0f072008-03-10 18:34:00 +0000879 AfterCallBB->getInstList().splice(AfterCallBB->begin(),
880 ReturnBB->getInstList());
Duncan Sands7c8fb1a2008-09-05 12:37:12 +0000881
Adrian Prantl15db52b2013-04-23 19:56:03 +0000882 if (CreatedBranchToNormalDest)
883 CreatedBranchToNormalDest->setDebugLoc(Returns[0]->getDebugLoc());
884
Devang Patel64d0f072008-03-10 18:34:00 +0000885 // Delete the return instruction now and empty ReturnBB now.
886 Returns[0]->eraseFromParent();
887 ReturnBB->eraseFromParent();
Chris Lattner6e79e552004-10-17 23:21:07 +0000888 } else if (!TheCall->use_empty()) {
889 // No returns, but something is using the return value of the call. Just
890 // nuke the result.
Owen Andersonb292b8c2009-07-30 23:03:37 +0000891 TheCall->replaceAllUsesWith(UndefValue::get(TheCall->getType()));
Chris Lattner18ef3fd2004-02-04 02:51:48 +0000892 }
Misha Brukmanb1c93172005-04-21 23:48:37 +0000893
Chris Lattner18ef3fd2004-02-04 02:51:48 +0000894 // Since we are now done with the Call/Invoke, we can delete it.
Chris Lattner6e79e552004-10-17 23:21:07 +0000895 TheCall->eraseFromParent();
Chris Lattner530d4bf2003-05-29 15:11:31 +0000896
Chris Lattnerfc3fe5c2003-08-24 04:06:56 +0000897 // We should always be able to fold the entry block of the function into the
898 // single predecessor of the block...
Chris Lattner0328d752004-04-16 05:17:59 +0000899 assert(cast<BranchInst>(Br)->isUnconditional() && "splitBasicBlock broken!");
Chris Lattnerfc3fe5c2003-08-24 04:06:56 +0000900 BasicBlock *CalleeEntry = cast<BranchInst>(Br)->getSuccessor(0);
Chris Lattner0fa8c7c2004-02-04 04:17:06 +0000901
Chris Lattner0328d752004-04-16 05:17:59 +0000902 // Splice the code entry block into calling block, right before the
903 // unconditional branch.
Eric Christopher96513122011-06-23 06:24:52 +0000904 CalleeEntry->replaceAllUsesWith(OrigBB); // Update PHI nodes
Jay Foad61ea0e42011-06-23 09:09:15 +0000905 OrigBB->getInstList().splice(Br, CalleeEntry->getInstList());
Chris Lattner0328d752004-04-16 05:17:59 +0000906
907 // Remove the unconditional branch.
908 OrigBB->getInstList().erase(Br);
909
910 // Now we can remove the CalleeEntry block, which is now empty.
911 Caller->getBasicBlockList().erase(CalleeEntry);
Duncan Sands7c8fb1a2008-09-05 12:37:12 +0000912
Duncan Sands9d9a4e22010-11-17 11:16:23 +0000913 // If we inserted a phi node, check to see if it has a single value (e.g. all
914 // the entries are the same or undef). If so, remove the PHI so it doesn't
915 // block other optimizations.
Bill Wendlingce0c2292012-01-31 01:01:16 +0000916 if (PHI) {
Duncan Sands9d9a4e22010-11-17 11:16:23 +0000917 if (Value *V = SimplifyInstruction(PHI, IFI.TD)) {
918 PHI->replaceAllUsesWith(V);
919 PHI->eraseFromParent();
920 }
Bill Wendlingce0c2292012-01-31 01:01:16 +0000921 }
Duncan Sands9d9a4e22010-11-17 11:16:23 +0000922
Chris Lattner530d4bf2003-05-29 15:11:31 +0000923 return true;
924}