InlineFunction.cpp revision 076863225ce070345ff7048f48b3550e00598a10
1ca398dc3989d35e8516489fd163e012133bd41cbChris Lattner//===- InlineFunction.cpp - Code to perform function inlining -------------===// 2fd93908ae8b9684fe71c239e3c6cfe13ff6a2663Misha Brukman// 3b576c94c15af9a440f69d9d03c2afead7971118cJohn Criswell// The LLVM Compiler Infrastructure 4b576c94c15af9a440f69d9d03c2afead7971118cJohn Criswell// 54ee451de366474b9c228b4e5fa573795a715216dChris Lattner// This file is distributed under the University of Illinois Open Source 64ee451de366474b9c228b4e5fa573795a715216dChris Lattner// License. See LICENSE.TXT for details. 7fd93908ae8b9684fe71c239e3c6cfe13ff6a2663Misha Brukman// 8b576c94c15af9a440f69d9d03c2afead7971118cJohn Criswell//===----------------------------------------------------------------------===// 9ca398dc3989d35e8516489fd163e012133bd41cbChris Lattner// 10ca398dc3989d35e8516489fd163e012133bd41cbChris Lattner// This file implements inlining of a function into a call site, resolving 11ca398dc3989d35e8516489fd163e012133bd41cbChris Lattner// parameters and the return value as appropriate. 12ca398dc3989d35e8516489fd163e012133bd41cbChris Lattner// 13ca398dc3989d35e8516489fd163e012133bd41cbChris Lattner//===----------------------------------------------------------------------===// 14ca398dc3989d35e8516489fd163e012133bd41cbChris Lattner 15ca398dc3989d35e8516489fd163e012133bd41cbChris Lattner#include "llvm/Transforms/Utils/Cloning.h" 163787e765facfad5ea62753922d940bcdd52afd57Chris Lattner#include "llvm/Constants.h" 177152c237b46a920b29d5605af934766b8f9a07a1Chris Lattner#include "llvm/DerivedTypes.h" 18ca398dc3989d35e8516489fd163e012133bd41cbChris Lattner#include "llvm/Module.h" 1980a38d245359cb0a3be8f78f5d7d911232886b9aChris Lattner#include "llvm/Instructions.h" 20517576d6f96a0acde9bab79553d89f4ceba20cf6Devang Patel#include "llvm/IntrinsicInst.h" 2180a38d245359cb0a3be8f78f5d7d911232886b9aChris Lattner#include "llvm/Intrinsics.h" 22eaf42abab6d465c38891345d999255871cf03943Devang Patel#include "llvm/Attributes.h" 23468fb1df7db466e5682ee44341c3990b599e8d6aChris Lattner#include "llvm/Analysis/CallGraph.h" 24517576d6f96a0acde9bab79553d89f4ceba20cf6Devang Patel#include "llvm/Analysis/DebugInfo.h" 25c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner#include "llvm/Target/TargetData.h" 2693e985f1b17aef62d58e3198a4604f9f6cfe8d19Chris Lattner#include "llvm/ADT/SmallVector.h" 27641ca93cff0f957fc5fb9dfb05d2a4a340aa8af7Devang Patel#include "llvm/ADT/StringExtras.h" 2880a38d245359cb0a3be8f78f5d7d911232886b9aChris Lattner#include "llvm/Support/CallSite.h" 29f7703df4968084c18c248c1feea9961c19a32e6aChris Lattnerusing namespace llvm; 30ca398dc3989d35e8516489fd163e012133bd41cbChris Lattner 3160915146f4d35e12f10dcdaa155596fac79184daChris Lattnerbool llvm::InlineFunction(CallInst *CI, InlineFunctionInfo &IFI) { 3260915146f4d35e12f10dcdaa155596fac79184daChris Lattner return InlineFunction(CallSite(CI), IFI); 33468fb1df7db466e5682ee44341c3990b599e8d6aChris Lattner} 3460915146f4d35e12f10dcdaa155596fac79184daChris Lattnerbool llvm::InlineFunction(InvokeInst *II, InlineFunctionInfo &IFI) { 3560915146f4d35e12f10dcdaa155596fac79184daChris Lattner return InlineFunction(CallSite(II), IFI); 36468fb1df7db466e5682ee44341c3990b599e8d6aChris Lattner} 3780a38d245359cb0a3be8f78f5d7d911232886b9aChris Lattner 38135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 39135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner/// HandleCallsInBlockInlinedThroughInvoke - When we inline a basic block into 40f61f89ae14cf332a014a598153137113af34002fEric Christopher/// an invoke, we have to turn all of the calls that can throw into 41135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner/// invokes. This function analyze BB to see if there are any calls, and if so, 42135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner/// it rewrites them to be invokes that jump to InvokeDest and fills in the PHI 4381dfb3885252fbf621b080827a080099864415f8Chris Lattner/// nodes in that block with the values specified in InvokeDestPHIValues. 44135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner/// 45135755dae4c3fa8003b76150689d5064aa4612eeChris Lattnerstatic void HandleCallsInBlockInlinedThroughInvoke(BasicBlock *BB, 46135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner BasicBlock *InvokeDest, 4781dfb3885252fbf621b080827a080099864415f8Chris Lattner const SmallVectorImpl<Value*> &InvokeDestPHIValues) { 48135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner for (BasicBlock::iterator BBI = BB->begin(), E = BB->end(); BBI != E; ) { 49135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner Instruction *I = BBI++; 50135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 51135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // We only need to check for function calls: inlined invoke 52135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // instructions require no special handling. 53135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner CallInst *CI = dyn_cast<CallInst>(I); 54135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner if (CI == 0) continue; 55135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 56135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // If this call cannot unwind, don't convert it to an invoke. 57135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner if (CI->doesNotThrow()) 58135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner continue; 59135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 60135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // Convert this function call into an invoke instruction. 61135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // First, split the basic block. 62135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner BasicBlock *Split = BB->splitBasicBlock(CI, CI->getName()+".noexc"); 63135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 64135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // Next, create the new invoke instruction, inserting it at the end 65135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // of the old basic block. 66551754c4958086cc6910da7c950f2875e212f5cfEric Christopher SmallVector<Value*, 8> InvokeArgs(CI->op_begin()+1, CI->op_end()); 67135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner InvokeInst *II = 68135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner InvokeInst::Create(CI->getCalledValue(), Split, InvokeDest, 69135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner InvokeArgs.begin(), InvokeArgs.end(), 70135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner CI->getName(), BB->getTerminator()); 71135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner II->setCallingConv(CI->getCallingConv()); 72135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner II->setAttributes(CI->getAttributes()); 73135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 7481dfb3885252fbf621b080827a080099864415f8Chris Lattner // Make sure that anything using the call now uses the invoke! This also 75076863225ce070345ff7048f48b3550e00598a10Chris Lattner // updates the CallGraph if present, because it uses a WeakVH. 76135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner CI->replaceAllUsesWith(II); 77135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 78135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // Delete the unconditional branch inserted by splitBasicBlock 79135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner BB->getInstList().pop_back(); 80135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner Split->getInstList().pop_front(); // Delete the original call 81135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 82135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // Update any PHI nodes in the exceptional block to indicate that 83135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // there is now a new entry in them. 84135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner unsigned i = 0; 85135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner for (BasicBlock::iterator I = InvokeDest->begin(); 86135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner isa<PHINode>(I); ++I, ++i) 87135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner cast<PHINode>(I)->addIncoming(InvokeDestPHIValues[i], BB); 88135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 89135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // This basic block is now complete, the caller will continue scanning the 90135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // next one. 91135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner return; 92135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner } 93135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner} 94135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 95135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 96cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner/// HandleInlinedInvoke - If we inlined an invoke site, we need to convert calls 97cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner/// in the body of the inlined function into invokes and turn unwind 98cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner/// instructions into branches to the invoke unwind dest. 99cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner/// 100dac5c4b10b387b55c2394cd98a64f3f1394df2e8Nick Lewycky/// II is the invoke instruction being inlined. FirstNewBlock is the first 101cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner/// block of the inlined code (the last block is the end of the function), 102cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner/// and InlineCodeInfo is information about the code that got inlined. 103cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattnerstatic void HandleInlinedInvoke(InvokeInst *II, BasicBlock *FirstNewBlock, 10481dfb3885252fbf621b080827a080099864415f8Chris Lattner ClonedCodeInfo &InlinedCodeInfo) { 105cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner BasicBlock *InvokeDest = II->getUnwindDest(); 106135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner SmallVector<Value*, 8> InvokeDestPHIValues; 107cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner 108cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner // If there are PHI nodes in the unwind destination block, we need to 109cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner // keep track of which values came into them from this invoke, then remove 110cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner // the entry for this block. 111cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner BasicBlock *InvokeBlock = II->getParent(); 112cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner for (BasicBlock::iterator I = InvokeDest->begin(); isa<PHINode>(I); ++I) { 113cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner PHINode *PN = cast<PHINode>(I); 114cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner // Save the value to use for this edge. 115cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner InvokeDestPHIValues.push_back(PN->getIncomingValueForBlock(InvokeBlock)); 116cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner } 117cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner 118cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner Function *Caller = FirstNewBlock->getParent(); 119a7212e58260f6d1ead0c4eec7af400cf6c0d289eDuncan Sands 120cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner // The inlined code is currently at the end of the function, scan from the 121cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner // start of the inlined code to its end, checking for stuff we need to 122135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // rewrite. If the code doesn't have calls or unwinds, we know there is 123135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // nothing to rewrite. 124135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner if (!InlinedCodeInfo.ContainsCalls && !InlinedCodeInfo.ContainsUnwinds) { 125135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // Now that everything is happy, we have one final detail. The PHI nodes in 126135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // the exception destination block still have entries due to the original 127135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // invoke instruction. Eliminate these entries (which might even delete the 128135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // PHI node) now. 129135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner InvokeDest->removePredecessor(II->getParent()); 130135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner return; 131135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner } 132135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 133135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner for (Function::iterator BB = FirstNewBlock, E = Caller->end(); BB != E; ++BB){ 134135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner if (InlinedCodeInfo.ContainsCalls) 135135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner HandleCallsInBlockInlinedThroughInvoke(BB, InvokeDest, 13681dfb3885252fbf621b080827a080099864415f8Chris Lattner InvokeDestPHIValues); 137135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 138135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner if (UnwindInst *UI = dyn_cast<UnwindInst>(BB->getTerminator())) { 139135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // An UnwindInst requires special handling when it gets inlined into an 140135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // invoke site. Once this happens, we know that the unwind would cause 141135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // a control transfer to the invoke exception destination, so we can 142135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // transform it into a direct branch to the exception destination. 143135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner BranchInst::Create(InvokeDest, UI); 144135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 145135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // Delete the unwind instruction! 146135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner UI->eraseFromParent(); 147135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 148135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // Update any PHI nodes in the exceptional block to indicate that 149135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // there is now a new entry in them. 150135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner unsigned i = 0; 151135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner for (BasicBlock::iterator I = InvokeDest->begin(); 152135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner isa<PHINode>(I); ++I, ++i) { 153135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner PHINode *PN = cast<PHINode>(I); 154135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner PN->addIncoming(InvokeDestPHIValues[i], BB); 155cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner } 156cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner } 157cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner } 158cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner 159cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner // Now that everything is happy, we have one final detail. The PHI nodes in 160cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner // the exception destination block still have entries due to the original 161cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner // invoke instruction. Eliminate these entries (which might even delete the 162cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner // PHI node) now. 163cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner InvokeDest->removePredecessor(II->getParent()); 164cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner} 165cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner 166d85340f4ec587e22b0239617f3b747a6df113894Chris Lattner/// UpdateCallGraphAfterInlining - Once we have cloned code over from a callee 167d85340f4ec587e22b0239617f3b747a6df113894Chris Lattner/// into the caller, update the specified callgraph to reflect the changes we 168d85340f4ec587e22b0239617f3b747a6df113894Chris Lattner/// made. Note that it's possible that not all code was copied over, so only 169d7b9851c4e634ed3599b1a4c70b1c76c90a11686Duncan Sands/// some edges of the callgraph may remain. 170d7b9851c4e634ed3599b1a4c70b1c76c90a11686Duncan Sandsstatic void UpdateCallGraphAfterInlining(CallSite CS, 171d85340f4ec587e22b0239617f3b747a6df113894Chris Lattner Function::iterator FirstNewBlock, 1725e665f559419c7f58a4fd9360cd488f065505c44Chris Lattner DenseMap<const Value*, Value*> &ValueMap, 173fe9af3b1f7e5d68ecc330bdf4f047d76838f8cc3Chris Lattner InlineFunctionInfo &IFI) { 174fe9af3b1f7e5d68ecc330bdf4f047d76838f8cc3Chris Lattner CallGraph &CG = *IFI.CG; 175d7b9851c4e634ed3599b1a4c70b1c76c90a11686Duncan Sands const Function *Caller = CS.getInstruction()->getParent()->getParent(); 176d7b9851c4e634ed3599b1a4c70b1c76c90a11686Duncan Sands const Function *Callee = CS.getCalledFunction(); 177468fb1df7db466e5682ee44341c3990b599e8d6aChris Lattner CallGraphNode *CalleeNode = CG[Callee]; 178468fb1df7db466e5682ee44341c3990b599e8d6aChris Lattner CallGraphNode *CallerNode = CG[Caller]; 179a7212e58260f6d1ead0c4eec7af400cf6c0d289eDuncan Sands 180d85340f4ec587e22b0239617f3b747a6df113894Chris Lattner // Since we inlined some uninlined call sites in the callee into the caller, 181468fb1df7db466e5682ee44341c3990b599e8d6aChris Lattner // add edges from the caller to all of the callees of the callee. 182c478e52bf4c12691037856ee103c66946afeab6cGabor Greif CallGraphNode::iterator I = CalleeNode->begin(), E = CalleeNode->end(); 183c478e52bf4c12691037856ee103c66946afeab6cGabor Greif 184c478e52bf4c12691037856ee103c66946afeab6cGabor Greif // Consider the case where CalleeNode == CallerNode. 185125329891f97baedef21e4b464ba70182c3fb45eGabor Greif CallGraphNode::CalledFunctionsVector CallCache; 186c478e52bf4c12691037856ee103c66946afeab6cGabor Greif if (CalleeNode == CallerNode) { 187c478e52bf4c12691037856ee103c66946afeab6cGabor Greif CallCache.assign(I, E); 188c478e52bf4c12691037856ee103c66946afeab6cGabor Greif I = CallCache.begin(); 189c478e52bf4c12691037856ee103c66946afeab6cGabor Greif E = CallCache.end(); 190c478e52bf4c12691037856ee103c66946afeab6cGabor Greif } 191c478e52bf4c12691037856ee103c66946afeab6cGabor Greif 192c478e52bf4c12691037856ee103c66946afeab6cGabor Greif for (; I != E; ++I) { 193a541b0fde2ab6b8b037edf113d42da41a2c5aae9Chris Lattner const Value *OrigCall = I->first; 194a7212e58260f6d1ead0c4eec7af400cf6c0d289eDuncan Sands 1955e665f559419c7f58a4fd9360cd488f065505c44Chris Lattner DenseMap<const Value*, Value*>::iterator VMI = ValueMap.find(OrigCall); 196981418bf1562d0b5b470ddc7d0034c9f3297b893Chris Lattner // Only copy the edge if the call was inlined! 197135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner if (VMI == ValueMap.end() || VMI->second == 0) 198135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner continue; 199135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 200135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // If the call was inlined, but then constant folded, there is no edge to 201135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // add. Check for this case. 202b957a5e41ed6288f4d033167f6413621a09655eeChris Lattner Instruction *NewCall = dyn_cast<Instruction>(VMI->second); 203b957a5e41ed6288f4d033167f6413621a09655eeChris Lattner if (NewCall == 0) continue; 204b957a5e41ed6288f4d033167f6413621a09655eeChris Lattner 205b957a5e41ed6288f4d033167f6413621a09655eeChris Lattner // It's possible that inlining the callsite will cause it to go from an 206b957a5e41ed6288f4d033167f6413621a09655eeChris Lattner // indirect to a direct call by resolving a function pointer. If this 207b957a5e41ed6288f4d033167f6413621a09655eeChris Lattner // happens, set the callee of the new call site to a more precise 208b957a5e41ed6288f4d033167f6413621a09655eeChris Lattner // destination. This can also happen if the call graph node of the caller 209b957a5e41ed6288f4d033167f6413621a09655eeChris Lattner // was just unnecessarily imprecise. 210b957a5e41ed6288f4d033167f6413621a09655eeChris Lattner if (I->second->getFunction() == 0) 211b957a5e41ed6288f4d033167f6413621a09655eeChris Lattner if (Function *F = CallSite(NewCall).getCalledFunction()) { 212b957a5e41ed6288f4d033167f6413621a09655eeChris Lattner // Indirect call site resolved to direct call. 213b957a5e41ed6288f4d033167f6413621a09655eeChris Lattner CallerNode->addCalledFunction(CallSite::get(NewCall), CG[F]); 214fe9af3b1f7e5d68ecc330bdf4f047d76838f8cc3Chris Lattner 215fe9af3b1f7e5d68ecc330bdf4f047d76838f8cc3Chris Lattner // Remember that this callsite got devirtualized for the client of 216fe9af3b1f7e5d68ecc330bdf4f047d76838f8cc3Chris Lattner // InlineFunction. 217fe9af3b1f7e5d68ecc330bdf4f047d76838f8cc3Chris Lattner IFI.DevirtualizedCalls.push_back(NewCall); 218b957a5e41ed6288f4d033167f6413621a09655eeChris Lattner continue; 219b957a5e41ed6288f4d033167f6413621a09655eeChris Lattner } 220b957a5e41ed6288f4d033167f6413621a09655eeChris Lattner 221b957a5e41ed6288f4d033167f6413621a09655eeChris Lattner CallerNode->addCalledFunction(CallSite::get(NewCall), I->second); 222d85340f4ec587e22b0239617f3b747a6df113894Chris Lattner } 223135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 22439fa32403e0b5e163f4f05566d6cde65e6c11095Dale Johannesen // Update the call graph by deleting the edge from Callee to Caller. We must 22539fa32403e0b5e163f4f05566d6cde65e6c11095Dale Johannesen // do this after the loop above in case Caller and Callee are the same. 22639fa32403e0b5e163f4f05566d6cde65e6c11095Dale Johannesen CallerNode->removeCallEdgeFor(CS); 227468fb1df7db466e5682ee44341c3990b599e8d6aChris Lattner} 228468fb1df7db466e5682ee44341c3990b599e8d6aChris Lattner 229ca398dc3989d35e8516489fd163e012133bd41cbChris Lattner// InlineFunction - This function inlines the called function into the basic 230ca398dc3989d35e8516489fd163e012133bd41cbChris Lattner// block of the caller. This returns false if it is not possible to inline this 231ca398dc3989d35e8516489fd163e012133bd41cbChris Lattner// call. The program is still in a well defined state if this occurs though. 232ca398dc3989d35e8516489fd163e012133bd41cbChris Lattner// 233fd93908ae8b9684fe71c239e3c6cfe13ff6a2663Misha Brukman// Note that this only does one level of inlining. For example, if the 234fd93908ae8b9684fe71c239e3c6cfe13ff6a2663Misha Brukman// instruction 'call B' is inlined, and 'B' calls 'C', then the call to 'C' now 235ca398dc3989d35e8516489fd163e012133bd41cbChris Lattner// exists in the instruction stream. Similiarly this will inline a recursive 236ca398dc3989d35e8516489fd163e012133bd41cbChris Lattner// function by one level. 237ca398dc3989d35e8516489fd163e012133bd41cbChris Lattner// 23860915146f4d35e12f10dcdaa155596fac79184daChris Lattnerbool llvm::InlineFunction(CallSite CS, InlineFunctionInfo &IFI) { 23980a38d245359cb0a3be8f78f5d7d911232886b9aChris Lattner Instruction *TheCall = CS.getInstruction(); 240e922c0201916e0b980ab3cfe91e1413e68d55647Owen Anderson LLVMContext &Context = TheCall->getContext(); 24180a38d245359cb0a3be8f78f5d7d911232886b9aChris Lattner assert(TheCall->getParent() && TheCall->getParent()->getParent() && 24280a38d245359cb0a3be8f78f5d7d911232886b9aChris Lattner "Instruction not in function!"); 243ca398dc3989d35e8516489fd163e012133bd41cbChris Lattner 24460915146f4d35e12f10dcdaa155596fac79184daChris Lattner // If IFI has any state in it, zap it before we fill it in. 24560915146f4d35e12f10dcdaa155596fac79184daChris Lattner IFI.reset(); 24660915146f4d35e12f10dcdaa155596fac79184daChris Lattner 24780a38d245359cb0a3be8f78f5d7d911232886b9aChris Lattner const Function *CalledFunc = CS.getCalledFunction(); 248ca398dc3989d35e8516489fd163e012133bd41cbChris Lattner if (CalledFunc == 0 || // Can't inline external function or indirect 2495cbf985dcbc89fba3208e7baf8b6f488b06d3ec9Reid Spencer CalledFunc->isDeclaration() || // call, or call to a vararg function! 2500623e90398153be61226ad19f1b40d3817874526Eric Christopher CalledFunc->getFunctionType()->isVarArg()) return false; 251ca398dc3989d35e8516489fd163e012133bd41cbChris Lattner 2521b49141821e98e4321bfe6234c7001c836b2a289Chris Lattner 253af9985c6b9d066cb70a0363fed699022d0ec196cChris Lattner // If the call to the callee is not a tail call, we must clear the 'tail' 2541b49141821e98e4321bfe6234c7001c836b2a289Chris Lattner // flags on any calls that we inline. 2551b49141821e98e4321bfe6234c7001c836b2a289Chris Lattner bool MustClearTailCallFlags = 256af9985c6b9d066cb70a0363fed699022d0ec196cChris Lattner !(isa<CallInst>(TheCall) && cast<CallInst>(TheCall)->isTailCall()); 2571b49141821e98e4321bfe6234c7001c836b2a289Chris Lattner 258f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands // If the call to the callee cannot throw, set the 'nounwind' flag on any 259f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands // calls that we inline. 260f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands bool MarkNoUnwind = CS.doesNotThrow(); 261f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands 26280a38d245359cb0a3be8f78f5d7d911232886b9aChris Lattner BasicBlock *OrigBB = TheCall->getParent(); 263ca398dc3989d35e8516489fd163e012133bd41cbChris Lattner Function *Caller = OrigBB->getParent(); 264ca398dc3989d35e8516489fd163e012133bd41cbChris Lattner 2650e13821c96937830ec817f08095c3cef1fdcac8dGordon Henriksen // GC poses two hazards to inlining, which only occur when the callee has GC: 2660e13821c96937830ec817f08095c3cef1fdcac8dGordon Henriksen // 1. If the caller has no GC, then the callee's GC must be propagated to the 2670e13821c96937830ec817f08095c3cef1fdcac8dGordon Henriksen // caller. 2680e13821c96937830ec817f08095c3cef1fdcac8dGordon Henriksen // 2. If the caller has a differing GC, it is invalid to inline. 2695eca075b74d62c621b160aa216b4cd50829a2cc7Gordon Henriksen if (CalledFunc->hasGC()) { 2705eca075b74d62c621b160aa216b4cd50829a2cc7Gordon Henriksen if (!Caller->hasGC()) 2715eca075b74d62c621b160aa216b4cd50829a2cc7Gordon Henriksen Caller->setGC(CalledFunc->getGC()); 2725eca075b74d62c621b160aa216b4cd50829a2cc7Gordon Henriksen else if (CalledFunc->getGC() != Caller->getGC()) 2730e13821c96937830ec817f08095c3cef1fdcac8dGordon Henriksen return false; 2740e13821c96937830ec817f08095c3cef1fdcac8dGordon Henriksen } 275a7212e58260f6d1ead0c4eec7af400cf6c0d289eDuncan Sands 2765052c911ec1be51ecb36e7f025c26412e9f1bfacChris Lattner // Get an iterator to the last basic block in the function, which will have 2775052c911ec1be51ecb36e7f025c26412e9f1bfacChris Lattner // the new function inlined after it. 2785052c911ec1be51ecb36e7f025c26412e9f1bfacChris Lattner // 2795052c911ec1be51ecb36e7f025c26412e9f1bfacChris Lattner Function::iterator LastBlock = &Caller->back(); 2805052c911ec1be51ecb36e7f025c26412e9f1bfacChris Lattner 2815e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner // Make sure to capture all of the return instructions from the cloned 2825e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner // function. 283ec1bea0d94372985a0a5eb283e644c6d0dd345dcChris Lattner SmallVector<ReturnInst*, 8> Returns; 284cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner ClonedCodeInfo InlinedFunctionInfo; 2850744f09efc53d3352ac1caffc61f6e8239201c3bDale Johannesen Function::iterator FirstNewBlock; 286f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands 2875e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner { // Scope to destroy ValueMap after cloning. 2885e665f559419c7f58a4fd9360cd488f065505c44Chris Lattner DenseMap<const Value*, Value*> ValueMap; 2895b5bc3032f97cfa7bfa3e22282d3a9c1ed05eec6Chris Lattner 2909614fcc640eb628cc5dfddb277ebae9f6cb61014Dan Gohman assert(CalledFunc->arg_size() == CS.arg_size() && 2915e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner "No varargs calls can be inlined!"); 292a7212e58260f6d1ead0c4eec7af400cf6c0d289eDuncan Sands 293c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner // Calculate the vector of arguments to pass into the function cloner, which 294c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner // matches up the formal to the actual argument values. 2955e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner CallSite::arg_iterator AI = CS.arg_begin(); 296c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner unsigned ArgNo = 0; 297e4d5c441e04bdc00ccf1804744af670655123b07Chris Lattner for (Function::const_arg_iterator I = CalledFunc->arg_begin(), 298c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner E = CalledFunc->arg_end(); I != E; ++I, ++AI, ++ArgNo) { 299c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner Value *ActualArg = *AI; 300a7212e58260f6d1ead0c4eec7af400cf6c0d289eDuncan Sands 301d82375c1c43db7f823dd4660d3495e76566699e3Duncan Sands // When byval arguments actually inlined, we need to make the copy implied 302d82375c1c43db7f823dd4660d3495e76566699e3Duncan Sands // by them explicit. However, we don't do this if the callee is readonly 303d82375c1c43db7f823dd4660d3495e76566699e3Duncan Sands // or readnone, because the copy would be unneeded: the callee doesn't 304d82375c1c43db7f823dd4660d3495e76566699e3Duncan Sands // modify the struct. 3050598866c052147c31b808391f58434ce3dbfb838Devang Patel if (CalledFunc->paramHasAttr(ArgNo+1, Attribute::ByVal) && 306d82375c1c43db7f823dd4660d3495e76566699e3Duncan Sands !CalledFunc->onlyReadsMemory()) { 307c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner const Type *AggTy = cast<PointerType>(I->getType())->getElementType(); 3081d0be15f89cb5056e20e2d24faa8d6afb1573bcaOwen Anderson const Type *VoidPtrTy = 309ac53a0b272452013124bfc70480aea5e41b60f40Duncan Sands Type::getInt8PtrTy(Context); 310a7212e58260f6d1ead0c4eec7af400cf6c0d289eDuncan Sands 311c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner // Create the alloca. If we have TargetData, use nice alignment. 312c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner unsigned Align = 1; 31360915146f4d35e12f10dcdaa155596fac79184daChris Lattner if (IFI.TD) Align = IFI.TD->getPrefTypeAlignment(AggTy); 31450dead06ffc107edb7e84857baaeeb09039c631cOwen Anderson Value *NewAlloca = new AllocaInst(AggTy, 0, Align, 3159adc0abad3c3ed40a268ccbcee0c74cb9e1359feOwen Anderson I->getName(), 3169adc0abad3c3ed40a268ccbcee0c74cb9e1359feOwen Anderson &*Caller->begin()->begin()); 317c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner // Emit a memcpy. 31820adc9dc4650313f017b27d9818eb2176238113dMon P Wang const Type *Tys[3] = {VoidPtrTy, VoidPtrTy, Type::getInt64Ty(Context)}; 319c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner Function *MemCpyFn = Intrinsic::getDeclaration(Caller->getParent(), 320824b958e6fb1236e92e4d07f3acf18fca107cdc0Chris Lattner Intrinsic::memcpy, 32120adc9dc4650313f017b27d9818eb2176238113dMon P Wang Tys, 3); 322c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner Value *DestCast = new BitCastInst(NewAlloca, VoidPtrTy, "tmp", TheCall); 323c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner Value *SrcCast = new BitCastInst(*AI, VoidPtrTy, "tmp", TheCall); 324a7212e58260f6d1ead0c4eec7af400cf6c0d289eDuncan Sands 325c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner Value *Size; 32660915146f4d35e12f10dcdaa155596fac79184daChris Lattner if (IFI.TD == 0) 327baf3c404409d5e47b13984a7f95bfbd6d1f2e79eOwen Anderson Size = ConstantExpr::getSizeOf(AggTy); 328c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner else 3291d0be15f89cb5056e20e2d24faa8d6afb1573bcaOwen Anderson Size = ConstantInt::get(Type::getInt64Ty(Context), 33060915146f4d35e12f10dcdaa155596fac79184daChris Lattner IFI.TD->getTypeStoreSize(AggTy)); 331a7212e58260f6d1ead0c4eec7af400cf6c0d289eDuncan Sands 332c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner // Always generate a memcpy of alignment 1 here because we don't know 333c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner // the alignment of the src pointer. Other optimizations can infer 334c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner // better alignment. 335c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner Value *CallArgs[] = { 3361d0be15f89cb5056e20e2d24faa8d6afb1573bcaOwen Anderson DestCast, SrcCast, Size, 33720adc9dc4650313f017b27d9818eb2176238113dMon P Wang ConstantInt::get(Type::getInt32Ty(Context), 1), 33820adc9dc4650313f017b27d9818eb2176238113dMon P Wang ConstantInt::get(Type::getInt1Ty(Context), 0) 339c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner }; 340c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner CallInst *TheMemCpy = 34120adc9dc4650313f017b27d9818eb2176238113dMon P Wang CallInst::Create(MemCpyFn, CallArgs, CallArgs+5, "", TheCall); 342a7212e58260f6d1ead0c4eec7af400cf6c0d289eDuncan Sands 343c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner // If we have a call graph, update it. 34460915146f4d35e12f10dcdaa155596fac79184daChris Lattner if (CallGraph *CG = IFI.CG) { 345c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner CallGraphNode *MemCpyCGN = CG->getOrInsertFunction(MemCpyFn); 346c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner CallGraphNode *CallerNode = (*CG)[Caller]; 347c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner CallerNode->addCalledFunction(TheMemCpy, MemCpyCGN); 348c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner } 349a7212e58260f6d1ead0c4eec7af400cf6c0d289eDuncan Sands 350c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner // Uses of the argument in the function should use our new alloca 351c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner // instead. 352c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner ActualArg = NewAlloca; 353c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner } 354a7212e58260f6d1ead0c4eec7af400cf6c0d289eDuncan Sands 355c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner ValueMap[I] = ActualArg; 356c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner } 357fd93908ae8b9684fe71c239e3c6cfe13ff6a2663Misha Brukman 3585b5bc3032f97cfa7bfa3e22282d3a9c1ed05eec6Chris Lattner // We want the inliner to prune the code as it copies. We would LOVE to 3595b5bc3032f97cfa7bfa3e22282d3a9c1ed05eec6Chris Lattner // have no dead or constant instructions leftover after inlining occurs 3605b5bc3032f97cfa7bfa3e22282d3a9c1ed05eec6Chris Lattner // (which can happen, e.g., because an argument was constant), but we'll be 3615b5bc3032f97cfa7bfa3e22282d3a9c1ed05eec6Chris Lattner // happy with whatever the cloner can do. 3625b5bc3032f97cfa7bfa3e22282d3a9c1ed05eec6Chris Lattner CloneAndPruneFunctionInto(Caller, CalledFunc, ValueMap, Returns, ".i", 36360915146f4d35e12f10dcdaa155596fac79184daChris Lattner &InlinedFunctionInfo, IFI.TD, TheCall); 364a7212e58260f6d1ead0c4eec7af400cf6c0d289eDuncan Sands 365d85340f4ec587e22b0239617f3b747a6df113894Chris Lattner // Remember the first block that is newly cloned over. 366d85340f4ec587e22b0239617f3b747a6df113894Chris Lattner FirstNewBlock = LastBlock; ++FirstNewBlock; 367a7212e58260f6d1ead0c4eec7af400cf6c0d289eDuncan Sands 368d85340f4ec587e22b0239617f3b747a6df113894Chris Lattner // Update the callgraph if requested. 36960915146f4d35e12f10dcdaa155596fac79184daChris Lattner if (IFI.CG) 370fe9af3b1f7e5d68ecc330bdf4f047d76838f8cc3Chris Lattner UpdateCallGraphAfterInlining(CS, FirstNewBlock, ValueMap, IFI); 371fd93908ae8b9684fe71c239e3c6cfe13ff6a2663Misha Brukman } 372a7212e58260f6d1ead0c4eec7af400cf6c0d289eDuncan Sands 373ca398dc3989d35e8516489fd163e012133bd41cbChris Lattner // If there are any alloca instructions in the block that used to be the entry 374ca398dc3989d35e8516489fd163e012133bd41cbChris Lattner // block for the callee, move them to the entry block of the caller. First 375ca398dc3989d35e8516489fd163e012133bd41cbChris Lattner // calculate which instruction they should be inserted before. We insert the 376ca398dc3989d35e8516489fd163e012133bd41cbChris Lattner // instructions at the end of the current alloca list. 377ca398dc3989d35e8516489fd163e012133bd41cbChris Lattner // 37821f20558d629f7ff8f64c20746d890d29328a544Chris Lattner { 37980a38d245359cb0a3be8f78f5d7d911232886b9aChris Lattner BasicBlock::iterator InsertPoint = Caller->begin()->begin(); 3805e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner for (BasicBlock::iterator I = FirstNewBlock->begin(), 381135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner E = FirstNewBlock->end(); I != E; ) { 382135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner AllocaInst *AI = dyn_cast<AllocaInst>(I++); 383135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner if (AI == 0) continue; 384135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 385135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // If the alloca is now dead, remove it. This often occurs due to code 386135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // specialization. 387135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner if (AI->use_empty()) { 388135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner AI->eraseFromParent(); 389135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner continue; 39033bb3c8be355d179ece8e751f6e0f0978d0dd038Chris Lattner } 391135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 392135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner if (!isa<Constant>(AI->getArraySize())) 393135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner continue; 394135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 3958f2718fbef6177966ff807af0732eb2431bd9a5fChris Lattner // Keep track of the static allocas that we inline into the caller if the 3968f2718fbef6177966ff807af0732eb2431bd9a5fChris Lattner // StaticAllocas pointer is non-null. 39760915146f4d35e12f10dcdaa155596fac79184daChris Lattner IFI.StaticAllocas.push_back(AI); 3988f2718fbef6177966ff807af0732eb2431bd9a5fChris Lattner 399135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // Scan for the block of allocas that we can move over, and move them 400135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // all at once. 401135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner while (isa<AllocaInst>(I) && 4028f2718fbef6177966ff807af0732eb2431bd9a5fChris Lattner isa<Constant>(cast<AllocaInst>(I)->getArraySize())) { 40360915146f4d35e12f10dcdaa155596fac79184daChris Lattner IFI.StaticAllocas.push_back(cast<AllocaInst>(I)); 404135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner ++I; 4058f2718fbef6177966ff807af0732eb2431bd9a5fChris Lattner } 406135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 407135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // Transfer all of the allocas over in a block. Using splice means 408135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // that the instructions aren't removed from the symbol table, then 409135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // reinserted. 410135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner Caller->getEntryBlock().getInstList().splice(InsertPoint, 411135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner FirstNewBlock->getInstList(), 412135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner AI, I); 413135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner } 41480a38d245359cb0a3be8f78f5d7d911232886b9aChris Lattner } 41580a38d245359cb0a3be8f78f5d7d911232886b9aChris Lattner 416bf229f488a7541abd979cc3fbe9c3ce1c100e5c0Chris Lattner // If the inlined code contained dynamic alloca instructions, wrap the inlined 417bf229f488a7541abd979cc3fbe9c3ce1c100e5c0Chris Lattner // code with llvm.stacksave/llvm.stackrestore intrinsics. 418bf229f488a7541abd979cc3fbe9c3ce1c100e5c0Chris Lattner if (InlinedFunctionInfo.ContainsDynamicAllocas) { 419bf229f488a7541abd979cc3fbe9c3ce1c100e5c0Chris Lattner Module *M = Caller->getParent(); 420bf229f488a7541abd979cc3fbe9c3ce1c100e5c0Chris Lattner // Get the two intrinsics we care about. 4216128df525501c333a650d097703c18d7e878f5e8Chris Lattner Function *StackSave = Intrinsic::getDeclaration(M, Intrinsic::stacksave); 4226128df525501c333a650d097703c18d7e878f5e8Chris Lattner Function *StackRestore=Intrinsic::getDeclaration(M,Intrinsic::stackrestore); 423d85340f4ec587e22b0239617f3b747a6df113894Chris Lattner 424d85340f4ec587e22b0239617f3b747a6df113894Chris Lattner // If we are preserving the callgraph, add edges to the stacksave/restore 425d85340f4ec587e22b0239617f3b747a6df113894Chris Lattner // functions for the calls we insert. 42621ba23d0d88cff57dcdf104cd6914dabcbc68131Chris Lattner CallGraphNode *StackSaveCGN = 0, *StackRestoreCGN = 0, *CallerNode = 0; 42760915146f4d35e12f10dcdaa155596fac79184daChris Lattner if (CallGraph *CG = IFI.CG) { 4286128df525501c333a650d097703c18d7e878f5e8Chris Lattner StackSaveCGN = CG->getOrInsertFunction(StackSave); 4296128df525501c333a650d097703c18d7e878f5e8Chris Lattner StackRestoreCGN = CG->getOrInsertFunction(StackRestore); 430d85340f4ec587e22b0239617f3b747a6df113894Chris Lattner CallerNode = (*CG)[Caller]; 431d85340f4ec587e22b0239617f3b747a6df113894Chris Lattner } 432a7212e58260f6d1ead0c4eec7af400cf6c0d289eDuncan Sands 433bf229f488a7541abd979cc3fbe9c3ce1c100e5c0Chris Lattner // Insert the llvm.stacksave. 434a7212e58260f6d1ead0c4eec7af400cf6c0d289eDuncan Sands CallInst *SavedPtr = CallInst::Create(StackSave, "savedstack", 435051a950000e21935165db56695e35bade668193bGabor Greif FirstNewBlock->begin()); 43660915146f4d35e12f10dcdaa155596fac79184daChris Lattner if (IFI.CG) CallerNode->addCalledFunction(SavedPtr, StackSaveCGN); 437a7212e58260f6d1ead0c4eec7af400cf6c0d289eDuncan Sands 438bf229f488a7541abd979cc3fbe9c3ce1c100e5c0Chris Lattner // Insert a call to llvm.stackrestore before any return instructions in the 439bf229f488a7541abd979cc3fbe9c3ce1c100e5c0Chris Lattner // inlined function. 440d85340f4ec587e22b0239617f3b747a6df113894Chris Lattner for (unsigned i = 0, e = Returns.size(); i != e; ++i) { 441051a950000e21935165db56695e35bade668193bGabor Greif CallInst *CI = CallInst::Create(StackRestore, SavedPtr, "", Returns[i]); 44260915146f4d35e12f10dcdaa155596fac79184daChris Lattner if (IFI.CG) CallerNode->addCalledFunction(CI, StackRestoreCGN); 443d85340f4ec587e22b0239617f3b747a6df113894Chris Lattner } 444468fb1df7db466e5682ee44341c3990b599e8d6aChris Lattner 445468fb1df7db466e5682ee44341c3990b599e8d6aChris Lattner // Count the number of StackRestore calls we insert. 446468fb1df7db466e5682ee44341c3990b599e8d6aChris Lattner unsigned NumStackRestores = Returns.size(); 447a7212e58260f6d1ead0c4eec7af400cf6c0d289eDuncan Sands 448bf229f488a7541abd979cc3fbe9c3ce1c100e5c0Chris Lattner // If we are inlining an invoke instruction, insert restores before each 449bf229f488a7541abd979cc3fbe9c3ce1c100e5c0Chris Lattner // unwind. These unwinds will be rewritten into branches later. 450bf229f488a7541abd979cc3fbe9c3ce1c100e5c0Chris Lattner if (InlinedFunctionInfo.ContainsUnwinds && isa<InvokeInst>(TheCall)) { 451bf229f488a7541abd979cc3fbe9c3ce1c100e5c0Chris Lattner for (Function::iterator BB = FirstNewBlock, E = Caller->end(); 452bf229f488a7541abd979cc3fbe9c3ce1c100e5c0Chris Lattner BB != E; ++BB) 453468fb1df7db466e5682ee44341c3990b599e8d6aChris Lattner if (UnwindInst *UI = dyn_cast<UnwindInst>(BB->getTerminator())) { 4546128df525501c333a650d097703c18d7e878f5e8Chris Lattner CallInst *CI = CallInst::Create(StackRestore, SavedPtr, "", UI); 45560915146f4d35e12f10dcdaa155596fac79184daChris Lattner if (IFI.CG) CallerNode->addCalledFunction(CI, StackRestoreCGN); 456468fb1df7db466e5682ee44341c3990b599e8d6aChris Lattner ++NumStackRestores; 457468fb1df7db466e5682ee44341c3990b599e8d6aChris Lattner } 458468fb1df7db466e5682ee44341c3990b599e8d6aChris Lattner } 459bf229f488a7541abd979cc3fbe9c3ce1c100e5c0Chris Lattner } 460bf229f488a7541abd979cc3fbe9c3ce1c100e5c0Chris Lattner 461a7212e58260f6d1ead0c4eec7af400cf6c0d289eDuncan Sands // If we are inlining tail call instruction through a call site that isn't 4621fdf4a859f03ce5aa4ce9acba29ce321c847388eChris Lattner // marked 'tail', we must remove the tail marker for any calls in the inlined 463f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands // code. Also, calls inlined through a 'nounwind' call site should be marked 464f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands // 'nounwind'. 465f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands if (InlinedFunctionInfo.ContainsCalls && 466f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands (MustClearTailCallFlags || MarkNoUnwind)) { 4671b49141821e98e4321bfe6234c7001c836b2a289Chris Lattner for (Function::iterator BB = FirstNewBlock, E = Caller->end(); 4681b49141821e98e4321bfe6234c7001c836b2a289Chris Lattner BB != E; ++BB) 4691b49141821e98e4321bfe6234c7001c836b2a289Chris Lattner for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E; ++I) 470f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands if (CallInst *CI = dyn_cast<CallInst>(I)) { 471f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands if (MustClearTailCallFlags) 472f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands CI->setTailCall(false); 473f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands if (MarkNoUnwind) 474f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands CI->setDoesNotThrow(); 475f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands } 4761b49141821e98e4321bfe6234c7001c836b2a289Chris Lattner } 4771b49141821e98e4321bfe6234c7001c836b2a289Chris Lattner 478f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands // If we are inlining through a 'nounwind' call site then any inlined 'unwind' 479f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands // instructions are unreachable. 480f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands if (InlinedFunctionInfo.ContainsUnwinds && MarkNoUnwind) 481f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands for (Function::iterator BB = FirstNewBlock, E = Caller->end(); 482f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands BB != E; ++BB) { 483f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands TerminatorInst *Term = BB->getTerminator(); 484f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands if (isa<UnwindInst>(Term)) { 4851d0be15f89cb5056e20e2d24faa8d6afb1573bcaOwen Anderson new UnreachableInst(Context, Term); 486f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands BB->getInstList().erase(Term); 487f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands } 488f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands } 489f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands 4905e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner // If we are inlining for an invoke instruction, we must make sure to rewrite 4915e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner // any inlined 'unwind' instructions into branches to the invoke exception 4925e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner // destination, and call instructions into invoke instructions. 493cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner if (InvokeInst *II = dyn_cast<InvokeInst>(TheCall)) 49481dfb3885252fbf621b080827a080099864415f8Chris Lattner HandleInlinedInvoke(II, FirstNewBlock, InlinedFunctionInfo); 4955e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner 49644a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner // If we cloned in _exactly one_ basic block, and if that block ends in a 49744a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner // return instruction, we splice the body of the inlined callee directly into 49844a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner // the calling basic block. 49944a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner if (Returns.size() == 1 && std::distance(FirstNewBlock, Caller->end()) == 1) { 50044a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner // Move all of the instructions right before the call. 50144a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner OrigBB->getInstList().splice(TheCall, FirstNewBlock->getInstList(), 50244a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner FirstNewBlock->begin(), FirstNewBlock->end()); 50344a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner // Remove the cloned basic block. 50444a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner Caller->getBasicBlockList().pop_back(); 505fd93908ae8b9684fe71c239e3c6cfe13ff6a2663Misha Brukman 50644a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner // If the call site was an invoke instruction, add a branch to the normal 50744a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner // destination. 50844a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner if (InvokeInst *II = dyn_cast<InvokeInst>(TheCall)) 509051a950000e21935165db56695e35bade668193bGabor Greif BranchInst::Create(II->getNormalDest(), TheCall); 51044a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner 51144a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner // If the return instruction returned a value, replace uses of the call with 51244a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner // uses of the returned value. 513dc00d42bb18a6748f43c365d9bd30c1ed0e800acDevang Patel if (!TheCall->use_empty()) { 514dc00d42bb18a6748f43c365d9bd30c1ed0e800acDevang Patel ReturnInst *R = Returns[0]; 5155877ad7e90de2179c15914ff9e8f1c72152cac30Eli Friedman if (TheCall == R->getReturnValue()) 5169e9a0d5fc26878e51a58a8b57900fcbf952c2691Owen Anderson TheCall->replaceAllUsesWith(UndefValue::get(TheCall->getType())); 5175877ad7e90de2179c15914ff9e8f1c72152cac30Eli Friedman else 5185877ad7e90de2179c15914ff9e8f1c72152cac30Eli Friedman TheCall->replaceAllUsesWith(R->getReturnValue()); 519dc00d42bb18a6748f43c365d9bd30c1ed0e800acDevang Patel } 52044a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner // Since we are now done with the Call/Invoke, we can delete it. 5211adec83ae84031bfa9f0bf209c5ee6c64906a1ffDan Gohman TheCall->eraseFromParent(); 52244a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner 52344a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner // Since we are now done with the return instruction, delete it also. 5241adec83ae84031bfa9f0bf209c5ee6c64906a1ffDan Gohman Returns[0]->eraseFromParent(); 52544a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner 52644a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner // We are now done with the inlining. 52744a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner return true; 52844a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner } 52944a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner 53044a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner // Otherwise, we have the normal case, of more than one block to inline or 53144a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner // multiple return sites. 53244a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner 5335e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner // We want to clone the entire callee function into the hole between the 5345e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner // "starter" and "ender" blocks. How we accomplish this depends on whether 5355e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner // this is an invoke instruction or a call instruction. 5365e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner BasicBlock *AfterCallBB; 5375e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner if (InvokeInst *II = dyn_cast<InvokeInst>(TheCall)) { 538fd93908ae8b9684fe71c239e3c6cfe13ff6a2663Misha Brukman 5395e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner // Add an unconditional branch to make this look like the CallInst case... 540051a950000e21935165db56695e35bade668193bGabor Greif BranchInst *NewBr = BranchInst::Create(II->getNormalDest(), TheCall); 541fd93908ae8b9684fe71c239e3c6cfe13ff6a2663Misha Brukman 5425e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner // Split the basic block. This guarantees that no PHI nodes will have to be 5435e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner // updated due to new incoming edges, and make the invoke case more 5445e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner // symmetric to the call case. 5455e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner AfterCallBB = OrigBB->splitBasicBlock(NewBr, 546284d1b88273eb1967c8faef407f1167791c760e0Chris Lattner CalledFunc->getName()+".exit"); 547fd93908ae8b9684fe71c239e3c6cfe13ff6a2663Misha Brukman 5485e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner } else { // It's a call 54944a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner // If this is a call instruction, we need to split the basic block that 55044a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner // the call lives in. 5515e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner // 5525e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner AfterCallBB = OrigBB->splitBasicBlock(TheCall, 553284d1b88273eb1967c8faef407f1167791c760e0Chris Lattner CalledFunc->getName()+".exit"); 5545e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner } 5555e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner 55644a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner // Change the branch that used to go to AfterCallBB to branch to the first 55744a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner // basic block of the inlined function. 55844a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner // 55944a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner TerminatorInst *Br = OrigBB->getTerminator(); 560fd93908ae8b9684fe71c239e3c6cfe13ff6a2663Misha Brukman assert(Br && Br->getOpcode() == Instruction::Br && 56144a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner "splitBasicBlock broken!"); 56244a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner Br->setOperand(0, FirstNewBlock); 56344a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner 56444a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner 56544a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner // Now that the function is correct, make it a little bit nicer. In 56644a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner // particular, move the basic blocks inserted from the end of the function 56744a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner // into the space made by splitting the source basic block. 56844a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner Caller->getBasicBlockList().splice(AfterCallBB, Caller->getBasicBlockList(), 56944a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner FirstNewBlock, Caller->end()); 57044a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner 5715e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner // Handle all of the return instructions that we just cloned in, and eliminate 5725e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner // any users of the original call/invoke instruction. 573b8f198af1b62f2ed48dcb914973a9d211dcba38bDevang Patel const Type *RTy = CalledFunc->getReturnType(); 5742c31750cd0ebdc83a890ace97dbb6249b3abe44eDan Gohman 575fc74abfba5128544a750fce22fdf13eb0403e3ceDan Gohman if (Returns.size() > 1) { 5765e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner // The PHI node should go at the front of the new basic block to merge all 5775e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner // possible incoming values. 578fc74abfba5128544a750fce22fdf13eb0403e3ceDan Gohman PHINode *PHI = 0; 5795e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner if (!TheCall->use_empty()) { 580fc74abfba5128544a750fce22fdf13eb0403e3ceDan Gohman PHI = PHINode::Create(RTy, TheCall->getName(), 581fc74abfba5128544a750fce22fdf13eb0403e3ceDan Gohman AfterCallBB->begin()); 582fc74abfba5128544a750fce22fdf13eb0403e3ceDan Gohman // Anything that used the result of the function call should now use the 583fc74abfba5128544a750fce22fdf13eb0403e3ceDan Gohman // PHI node as their operand. 584a7212e58260f6d1ead0c4eec7af400cf6c0d289eDuncan Sands TheCall->replaceAllUsesWith(PHI); 5855e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner } 586fd93908ae8b9684fe71c239e3c6cfe13ff6a2663Misha Brukman 587c478e52bf4c12691037856ee103c66946afeab6cGabor Greif // Loop over all of the return instructions adding entries to the PHI node 588c478e52bf4c12691037856ee103c66946afeab6cGabor Greif // as appropriate. 589fc74abfba5128544a750fce22fdf13eb0403e3ceDan Gohman if (PHI) { 590fc74abfba5128544a750fce22fdf13eb0403e3ceDan Gohman for (unsigned i = 0, e = Returns.size(); i != e; ++i) { 591fc74abfba5128544a750fce22fdf13eb0403e3ceDan Gohman ReturnInst *RI = Returns[i]; 592fc74abfba5128544a750fce22fdf13eb0403e3ceDan Gohman assert(RI->getReturnValue()->getType() == PHI->getType() && 593fc74abfba5128544a750fce22fdf13eb0403e3ceDan Gohman "Ret value not consistent in function!"); 594fc74abfba5128544a750fce22fdf13eb0403e3ceDan Gohman PHI->addIncoming(RI->getReturnValue(), RI->getParent()); 5955e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner } 596c581acbbba3cb1af6a08e17314b26344333f9267Chris Lattner 597c581acbbba3cb1af6a08e17314b26344333f9267Chris Lattner // Now that we inserted the PHI, check to see if it has a single value 598c581acbbba3cb1af6a08e17314b26344333f9267Chris Lattner // (e.g. all the entries are the same or undef). If so, remove the PHI so 599c581acbbba3cb1af6a08e17314b26344333f9267Chris Lattner // it doesn't block other optimizations. 600c581acbbba3cb1af6a08e17314b26344333f9267Chris Lattner if (Value *V = PHI->hasConstantValue()) { 601c581acbbba3cb1af6a08e17314b26344333f9267Chris Lattner PHI->replaceAllUsesWith(V); 602c581acbbba3cb1af6a08e17314b26344333f9267Chris Lattner PHI->eraseFromParent(); 603c581acbbba3cb1af6a08e17314b26344333f9267Chris Lattner } 60412a466b9d0e27be453cfa05cff18acc9d7c1cfbaDevang Patel } 605fd93908ae8b9684fe71c239e3c6cfe13ff6a2663Misha Brukman 606c581acbbba3cb1af6a08e17314b26344333f9267Chris Lattner 607de62aeaec49ddcf4a4c61fbbb3a22d3a4dd448f0Gabor Greif // Add a branch to the merge points and remove return instructions. 60812a466b9d0e27be453cfa05cff18acc9d7c1cfbaDevang Patel for (unsigned i = 0, e = Returns.size(); i != e; ++i) { 60912a466b9d0e27be453cfa05cff18acc9d7c1cfbaDevang Patel ReturnInst *RI = Returns[i]; 6100744f09efc53d3352ac1caffc61f6e8239201c3bDale Johannesen BranchInst::Create(AfterCallBB, RI); 611b8f198af1b62f2ed48dcb914973a9d211dcba38bDevang Patel RI->eraseFromParent(); 6125e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner } 613b8f198af1b62f2ed48dcb914973a9d211dcba38bDevang Patel } else if (!Returns.empty()) { 614b8f198af1b62f2ed48dcb914973a9d211dcba38bDevang Patel // Otherwise, if there is exactly one return value, just replace anything 615b8f198af1b62f2ed48dcb914973a9d211dcba38bDevang Patel // using the return value of the call with the computed value. 6165877ad7e90de2179c15914ff9e8f1c72152cac30Eli Friedman if (!TheCall->use_empty()) { 6175877ad7e90de2179c15914ff9e8f1c72152cac30Eli Friedman if (TheCall == Returns[0]->getReturnValue()) 6189e9a0d5fc26878e51a58a8b57900fcbf952c2691Owen Anderson TheCall->replaceAllUsesWith(UndefValue::get(TheCall->getType())); 6195877ad7e90de2179c15914ff9e8f1c72152cac30Eli Friedman else 6205877ad7e90de2179c15914ff9e8f1c72152cac30Eli Friedman TheCall->replaceAllUsesWith(Returns[0]->getReturnValue()); 6215877ad7e90de2179c15914ff9e8f1c72152cac30Eli Friedman } 622a7212e58260f6d1ead0c4eec7af400cf6c0d289eDuncan Sands 623b8f198af1b62f2ed48dcb914973a9d211dcba38bDevang Patel // Splice the code from the return block into the block that it will return 624b8f198af1b62f2ed48dcb914973a9d211dcba38bDevang Patel // to, which contains the code that was after the call. 625b8f198af1b62f2ed48dcb914973a9d211dcba38bDevang Patel BasicBlock *ReturnBB = Returns[0]->getParent(); 626b8f198af1b62f2ed48dcb914973a9d211dcba38bDevang Patel AfterCallBB->getInstList().splice(AfterCallBB->begin(), 627b8f198af1b62f2ed48dcb914973a9d211dcba38bDevang Patel ReturnBB->getInstList()); 628a7212e58260f6d1ead0c4eec7af400cf6c0d289eDuncan Sands 629b8f198af1b62f2ed48dcb914973a9d211dcba38bDevang Patel // Update PHI nodes that use the ReturnBB to use the AfterCallBB. 630b8f198af1b62f2ed48dcb914973a9d211dcba38bDevang Patel ReturnBB->replaceAllUsesWith(AfterCallBB); 631a7212e58260f6d1ead0c4eec7af400cf6c0d289eDuncan Sands 632b8f198af1b62f2ed48dcb914973a9d211dcba38bDevang Patel // Delete the return instruction now and empty ReturnBB now. 633b8f198af1b62f2ed48dcb914973a9d211dcba38bDevang Patel Returns[0]->eraseFromParent(); 634b8f198af1b62f2ed48dcb914973a9d211dcba38bDevang Patel ReturnBB->eraseFromParent(); 6353787e765facfad5ea62753922d940bcdd52afd57Chris Lattner } else if (!TheCall->use_empty()) { 6363787e765facfad5ea62753922d940bcdd52afd57Chris Lattner // No returns, but something is using the return value of the call. Just 6373787e765facfad5ea62753922d940bcdd52afd57Chris Lattner // nuke the result. 6389e9a0d5fc26878e51a58a8b57900fcbf952c2691Owen Anderson TheCall->replaceAllUsesWith(UndefValue::get(TheCall->getType())); 6395e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner } 640fd93908ae8b9684fe71c239e3c6cfe13ff6a2663Misha Brukman 6415e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner // Since we are now done with the Call/Invoke, we can delete it. 6423787e765facfad5ea62753922d940bcdd52afd57Chris Lattner TheCall->eraseFromParent(); 643ca398dc3989d35e8516489fd163e012133bd41cbChris Lattner 6447152c237b46a920b29d5605af934766b8f9a07a1Chris Lattner // We should always be able to fold the entry block of the function into the 6457152c237b46a920b29d5605af934766b8f9a07a1Chris Lattner // single predecessor of the block... 646cd01ae5c7071fb99a665b2bbea7428d769792ab8Chris Lattner assert(cast<BranchInst>(Br)->isUnconditional() && "splitBasicBlock broken!"); 6477152c237b46a920b29d5605af934766b8f9a07a1Chris Lattner BasicBlock *CalleeEntry = cast<BranchInst>(Br)->getSuccessor(0); 64844a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner 649cd01ae5c7071fb99a665b2bbea7428d769792ab8Chris Lattner // Splice the code entry block into calling block, right before the 650cd01ae5c7071fb99a665b2bbea7428d769792ab8Chris Lattner // unconditional branch. 651cd01ae5c7071fb99a665b2bbea7428d769792ab8Chris Lattner OrigBB->getInstList().splice(Br, CalleeEntry->getInstList()); 652cd01ae5c7071fb99a665b2bbea7428d769792ab8Chris Lattner CalleeEntry->replaceAllUsesWith(OrigBB); // Update PHI nodes 653cd01ae5c7071fb99a665b2bbea7428d769792ab8Chris Lattner 654cd01ae5c7071fb99a665b2bbea7428d769792ab8Chris Lattner // Remove the unconditional branch. 655cd01ae5c7071fb99a665b2bbea7428d769792ab8Chris Lattner OrigBB->getInstList().erase(Br); 656cd01ae5c7071fb99a665b2bbea7428d769792ab8Chris Lattner 657cd01ae5c7071fb99a665b2bbea7428d769792ab8Chris Lattner // Now we can remove the CalleeEntry block, which is now empty. 658cd01ae5c7071fb99a665b2bbea7428d769792ab8Chris Lattner Caller->getBasicBlockList().erase(CalleeEntry); 659a7212e58260f6d1ead0c4eec7af400cf6c0d289eDuncan Sands 660ca398dc3989d35e8516489fd163e012133bd41cbChris Lattner return true; 661ca398dc3989d35e8516489fd163e012133bd41cbChris Lattner} 662