InlineFunction.cpp revision 39add23dc54a1580983b1901384688d6622daa3b
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" 256fb881c036c32728c4a128d81b6083457e534e09Duncan Sands#include "llvm/Analysis/InstructionSimplify.h" 26c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner#include "llvm/Target/TargetData.h" 2793e985f1b17aef62d58e3198a4604f9f6cfe8d19Chris Lattner#include "llvm/ADT/SmallVector.h" 28641ca93cff0f957fc5fb9dfb05d2a4a340aa8af7Devang Patel#include "llvm/ADT/StringExtras.h" 2980a38d245359cb0a3be8f78f5d7d911232886b9aChris Lattner#include "llvm/Support/CallSite.h" 30f7703df4968084c18c248c1feea9961c19a32e6aChris Lattnerusing namespace llvm; 31ca398dc3989d35e8516489fd163e012133bd41cbChris Lattner 3260915146f4d35e12f10dcdaa155596fac79184daChris Lattnerbool llvm::InlineFunction(CallInst *CI, InlineFunctionInfo &IFI) { 3360915146f4d35e12f10dcdaa155596fac79184daChris Lattner return InlineFunction(CallSite(CI), IFI); 34468fb1df7db466e5682ee44341c3990b599e8d6aChris Lattner} 3560915146f4d35e12f10dcdaa155596fac79184daChris Lattnerbool llvm::InlineFunction(InvokeInst *II, InlineFunctionInfo &IFI) { 3660915146f4d35e12f10dcdaa155596fac79184daChris Lattner return InlineFunction(CallSite(II), IFI); 37468fb1df7db466e5682ee44341c3990b599e8d6aChris Lattner} 3880a38d245359cb0a3be8f78f5d7d911232886b9aChris Lattner 39135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 40135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner/// HandleCallsInBlockInlinedThroughInvoke - When we inline a basic block into 41f61f89ae14cf332a014a598153137113af34002fEric Christopher/// an invoke, we have to turn all of the calls that can throw into 42135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner/// invokes. This function analyze BB to see if there are any calls, and if so, 43135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner/// it rewrites them to be invokes that jump to InvokeDest and fills in the PHI 4481dfb3885252fbf621b080827a080099864415f8Chris Lattner/// nodes in that block with the values specified in InvokeDestPHIValues. 45135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner/// 46135755dae4c3fa8003b76150689d5064aa4612eeChris Lattnerstatic void HandleCallsInBlockInlinedThroughInvoke(BasicBlock *BB, 47135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner BasicBlock *InvokeDest, 4881dfb3885252fbf621b080827a080099864415f8Chris Lattner const SmallVectorImpl<Value*> &InvokeDestPHIValues) { 49135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner for (BasicBlock::iterator BBI = BB->begin(), E = BB->end(); BBI != E; ) { 50135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner Instruction *I = BBI++; 51135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 52135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // We only need to check for function calls: inlined invoke 53135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // instructions require no special handling. 54135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner CallInst *CI = dyn_cast<CallInst>(I); 55135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner if (CI == 0) continue; 56135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 57135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // If this call cannot unwind, don't convert it to an invoke. 58135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner if (CI->doesNotThrow()) 59135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner continue; 60135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 61135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // Convert this function call into an invoke instruction. 62135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // First, split the basic block. 63135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner BasicBlock *Split = BB->splitBasicBlock(CI, CI->getName()+".noexc"); 64135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 65135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // Next, create the new invoke instruction, inserting it at the end 66135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // of the old basic block. 67aeff385e3e21a3cde564ef49da1bdd7b745aa44cGabor Greif ImmutableCallSite CS(CI); 68aeff385e3e21a3cde564ef49da1bdd7b745aa44cGabor Greif SmallVector<Value*, 8> InvokeArgs(CS.arg_begin(), CS.arg_end()); 69135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner InvokeInst *II = 70135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner InvokeInst::Create(CI->getCalledValue(), Split, InvokeDest, 71135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner InvokeArgs.begin(), InvokeArgs.end(), 72135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner CI->getName(), BB->getTerminator()); 73135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner II->setCallingConv(CI->getCallingConv()); 74135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner II->setAttributes(CI->getAttributes()); 75135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 7681dfb3885252fbf621b080827a080099864415f8Chris Lattner // Make sure that anything using the call now uses the invoke! This also 77076863225ce070345ff7048f48b3550e00598a10Chris Lattner // updates the CallGraph if present, because it uses a WeakVH. 78135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner CI->replaceAllUsesWith(II); 79135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 80135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // Delete the unconditional branch inserted by splitBasicBlock 81135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner BB->getInstList().pop_back(); 82135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner Split->getInstList().pop_front(); // Delete the original call 83135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 84135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // Update any PHI nodes in the exceptional block to indicate that 85135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // there is now a new entry in them. 86135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner unsigned i = 0; 87135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner for (BasicBlock::iterator I = InvokeDest->begin(); 88135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner isa<PHINode>(I); ++I, ++i) 89135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner cast<PHINode>(I)->addIncoming(InvokeDestPHIValues[i], BB); 90135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 91135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // This basic block is now complete, the caller will continue scanning the 92135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // next one. 93135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner return; 94135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner } 95135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner} 96135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 97135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 98cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner/// HandleInlinedInvoke - If we inlined an invoke site, we need to convert calls 99cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner/// in the body of the inlined function into invokes and turn unwind 100cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner/// instructions into branches to the invoke unwind dest. 101cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner/// 102dac5c4b10b387b55c2394cd98a64f3f1394df2e8Nick Lewycky/// II is the invoke instruction being inlined. FirstNewBlock is the first 103cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner/// block of the inlined code (the last block is the end of the function), 104cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner/// and InlineCodeInfo is information about the code that got inlined. 105cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattnerstatic void HandleInlinedInvoke(InvokeInst *II, BasicBlock *FirstNewBlock, 10681dfb3885252fbf621b080827a080099864415f8Chris Lattner ClonedCodeInfo &InlinedCodeInfo) { 107cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner BasicBlock *InvokeDest = II->getUnwindDest(); 108135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner SmallVector<Value*, 8> InvokeDestPHIValues; 109cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner 110cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner // If there are PHI nodes in the unwind destination block, we need to 111cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner // keep track of which values came into them from this invoke, then remove 112cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner // the entry for this block. 113cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner BasicBlock *InvokeBlock = II->getParent(); 114cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner for (BasicBlock::iterator I = InvokeDest->begin(); isa<PHINode>(I); ++I) { 115cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner PHINode *PN = cast<PHINode>(I); 116cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner // Save the value to use for this edge. 117cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner InvokeDestPHIValues.push_back(PN->getIncomingValueForBlock(InvokeBlock)); 118cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner } 119cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner 120cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner Function *Caller = FirstNewBlock->getParent(); 121a7212e58260f6d1ead0c4eec7af400cf6c0d289eDuncan Sands 122cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner // The inlined code is currently at the end of the function, scan from the 123cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner // start of the inlined code to its end, checking for stuff we need to 124135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // rewrite. If the code doesn't have calls or unwinds, we know there is 125135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // nothing to rewrite. 126135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner if (!InlinedCodeInfo.ContainsCalls && !InlinedCodeInfo.ContainsUnwinds) { 127135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // Now that everything is happy, we have one final detail. The PHI nodes in 128135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // the exception destination block still have entries due to the original 129135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // invoke instruction. Eliminate these entries (which might even delete the 130135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // PHI node) now. 131135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner InvokeDest->removePredecessor(II->getParent()); 132135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner return; 133135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner } 134135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 135135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner for (Function::iterator BB = FirstNewBlock, E = Caller->end(); BB != E; ++BB){ 136135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner if (InlinedCodeInfo.ContainsCalls) 137135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner HandleCallsInBlockInlinedThroughInvoke(BB, InvokeDest, 13881dfb3885252fbf621b080827a080099864415f8Chris Lattner InvokeDestPHIValues); 139135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 140135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner if (UnwindInst *UI = dyn_cast<UnwindInst>(BB->getTerminator())) { 141135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // An UnwindInst requires special handling when it gets inlined into an 142135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // invoke site. Once this happens, we know that the unwind would cause 143135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // a control transfer to the invoke exception destination, so we can 144135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // transform it into a direct branch to the exception destination. 145135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner BranchInst::Create(InvokeDest, UI); 146135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 147135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // Delete the unwind instruction! 148135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner UI->eraseFromParent(); 149135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 150135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // Update any PHI nodes in the exceptional block to indicate that 151135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // there is now a new entry in them. 152135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner unsigned i = 0; 153135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner for (BasicBlock::iterator I = InvokeDest->begin(); 154135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner isa<PHINode>(I); ++I, ++i) { 155135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner PHINode *PN = cast<PHINode>(I); 156135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner PN->addIncoming(InvokeDestPHIValues[i], BB); 157cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner } 158cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner } 159cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner } 160cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner 161cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner // Now that everything is happy, we have one final detail. The PHI nodes in 162cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner // the exception destination block still have entries due to the original 163cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner // invoke instruction. Eliminate these entries (which might even delete the 164cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner // PHI node) now. 165cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner InvokeDest->removePredecessor(II->getParent()); 166cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner} 167cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner 168d85340f4ec587e22b0239617f3b747a6df113894Chris Lattner/// UpdateCallGraphAfterInlining - Once we have cloned code over from a callee 169d85340f4ec587e22b0239617f3b747a6df113894Chris Lattner/// into the caller, update the specified callgraph to reflect the changes we 170d85340f4ec587e22b0239617f3b747a6df113894Chris Lattner/// made. Note that it's possible that not all code was copied over, so only 171d7b9851c4e634ed3599b1a4c70b1c76c90a11686Duncan Sands/// some edges of the callgraph may remain. 172d7b9851c4e634ed3599b1a4c70b1c76c90a11686Duncan Sandsstatic void UpdateCallGraphAfterInlining(CallSite CS, 173d85340f4ec587e22b0239617f3b747a6df113894Chris Lattner Function::iterator FirstNewBlock, 1741ed219a9d2279ce5a5bbcf16d9b7ccc05cce638cRafael Espindola ValueToValueMapTy &VMap, 175fe9af3b1f7e5d68ecc330bdf4f047d76838f8cc3Chris Lattner InlineFunctionInfo &IFI) { 176fe9af3b1f7e5d68ecc330bdf4f047d76838f8cc3Chris Lattner CallGraph &CG = *IFI.CG; 177d7b9851c4e634ed3599b1a4c70b1c76c90a11686Duncan Sands const Function *Caller = CS.getInstruction()->getParent()->getParent(); 178d7b9851c4e634ed3599b1a4c70b1c76c90a11686Duncan Sands const Function *Callee = CS.getCalledFunction(); 179468fb1df7db466e5682ee44341c3990b599e8d6aChris Lattner CallGraphNode *CalleeNode = CG[Callee]; 180468fb1df7db466e5682ee44341c3990b599e8d6aChris Lattner CallGraphNode *CallerNode = CG[Caller]; 181a7212e58260f6d1ead0c4eec7af400cf6c0d289eDuncan Sands 182d85340f4ec587e22b0239617f3b747a6df113894Chris Lattner // Since we inlined some uninlined call sites in the callee into the caller, 183468fb1df7db466e5682ee44341c3990b599e8d6aChris Lattner // add edges from the caller to all of the callees of the callee. 184c478e52bf4c12691037856ee103c66946afeab6cGabor Greif CallGraphNode::iterator I = CalleeNode->begin(), E = CalleeNode->end(); 185c478e52bf4c12691037856ee103c66946afeab6cGabor Greif 186c478e52bf4c12691037856ee103c66946afeab6cGabor Greif // Consider the case where CalleeNode == CallerNode. 187125329891f97baedef21e4b464ba70182c3fb45eGabor Greif CallGraphNode::CalledFunctionsVector CallCache; 188c478e52bf4c12691037856ee103c66946afeab6cGabor Greif if (CalleeNode == CallerNode) { 189c478e52bf4c12691037856ee103c66946afeab6cGabor Greif CallCache.assign(I, E); 190c478e52bf4c12691037856ee103c66946afeab6cGabor Greif I = CallCache.begin(); 191c478e52bf4c12691037856ee103c66946afeab6cGabor Greif E = CallCache.end(); 192c478e52bf4c12691037856ee103c66946afeab6cGabor Greif } 193c478e52bf4c12691037856ee103c66946afeab6cGabor Greif 194c478e52bf4c12691037856ee103c66946afeab6cGabor Greif for (; I != E; ++I) { 195a541b0fde2ab6b8b037edf113d42da41a2c5aae9Chris Lattner const Value *OrigCall = I->first; 196a7212e58260f6d1ead0c4eec7af400cf6c0d289eDuncan Sands 1971ed219a9d2279ce5a5bbcf16d9b7ccc05cce638cRafael Espindola ValueToValueMapTy::iterator VMI = VMap.find(OrigCall); 198981418bf1562d0b5b470ddc7d0034c9f3297b893Chris Lattner // Only copy the edge if the call was inlined! 19929d3dd8a64791031eea00ffbae51843dc9982df9Devang Patel if (VMI == VMap.end() || VMI->second == 0) 200135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner continue; 201135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 202135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // If the call was inlined, but then constant folded, there is no edge to 203135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // add. Check for this case. 204b957a5e41ed6288f4d033167f6413621a09655eeChris Lattner Instruction *NewCall = dyn_cast<Instruction>(VMI->second); 205b957a5e41ed6288f4d033167f6413621a09655eeChris Lattner if (NewCall == 0) continue; 2060ca2f28458ae9122f413a4092ddcee33a9dd21c6Chris Lattner 2070ca2f28458ae9122f413a4092ddcee33a9dd21c6Chris Lattner // Remember that this call site got inlined for the client of 2080ca2f28458ae9122f413a4092ddcee33a9dd21c6Chris Lattner // InlineFunction. 2090ca2f28458ae9122f413a4092ddcee33a9dd21c6Chris Lattner IFI.InlinedCalls.push_back(NewCall); 2100ca2f28458ae9122f413a4092ddcee33a9dd21c6Chris Lattner 211b957a5e41ed6288f4d033167f6413621a09655eeChris Lattner // It's possible that inlining the callsite will cause it to go from an 212b957a5e41ed6288f4d033167f6413621a09655eeChris Lattner // indirect to a direct call by resolving a function pointer. If this 213b957a5e41ed6288f4d033167f6413621a09655eeChris Lattner // happens, set the callee of the new call site to a more precise 214b957a5e41ed6288f4d033167f6413621a09655eeChris Lattner // destination. This can also happen if the call graph node of the caller 215b957a5e41ed6288f4d033167f6413621a09655eeChris Lattner // was just unnecessarily imprecise. 216b957a5e41ed6288f4d033167f6413621a09655eeChris Lattner if (I->second->getFunction() == 0) 217b957a5e41ed6288f4d033167f6413621a09655eeChris Lattner if (Function *F = CallSite(NewCall).getCalledFunction()) { 218b957a5e41ed6288f4d033167f6413621a09655eeChris Lattner // Indirect call site resolved to direct call. 21986099345db95fdce6960ab62fbd9cb0cf96875f7Gabor Greif CallerNode->addCalledFunction(CallSite(NewCall), CG[F]); 22086099345db95fdce6960ab62fbd9cb0cf96875f7Gabor Greif 221b957a5e41ed6288f4d033167f6413621a09655eeChris Lattner continue; 222b957a5e41ed6288f4d033167f6413621a09655eeChris Lattner } 22386099345db95fdce6960ab62fbd9cb0cf96875f7Gabor Greif 22486099345db95fdce6960ab62fbd9cb0cf96875f7Gabor Greif CallerNode->addCalledFunction(CallSite(NewCall), I->second); 225d85340f4ec587e22b0239617f3b747a6df113894Chris Lattner } 226135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 22739fa32403e0b5e163f4f05566d6cde65e6c11095Dale Johannesen // Update the call graph by deleting the edge from Callee to Caller. We must 22839fa32403e0b5e163f4f05566d6cde65e6c11095Dale Johannesen // do this after the loop above in case Caller and Callee are the same. 22939fa32403e0b5e163f4f05566d6cde65e6c11095Dale Johannesen CallerNode->removeCallEdgeFor(CS); 230468fb1df7db466e5682ee44341c3990b599e8d6aChris Lattner} 231468fb1df7db466e5682ee44341c3990b599e8d6aChris Lattner 232ca398dc3989d35e8516489fd163e012133bd41cbChris Lattner// InlineFunction - This function inlines the called function into the basic 233ca398dc3989d35e8516489fd163e012133bd41cbChris Lattner// block of the caller. This returns false if it is not possible to inline this 234ca398dc3989d35e8516489fd163e012133bd41cbChris Lattner// call. The program is still in a well defined state if this occurs though. 235ca398dc3989d35e8516489fd163e012133bd41cbChris Lattner// 236fd93908ae8b9684fe71c239e3c6cfe13ff6a2663Misha Brukman// Note that this only does one level of inlining. For example, if the 237fd93908ae8b9684fe71c239e3c6cfe13ff6a2663Misha Brukman// instruction 'call B' is inlined, and 'B' calls 'C', then the call to 'C' now 238ca398dc3989d35e8516489fd163e012133bd41cbChris Lattner// exists in the instruction stream. Similiarly this will inline a recursive 239ca398dc3989d35e8516489fd163e012133bd41cbChris Lattner// function by one level. 240ca398dc3989d35e8516489fd163e012133bd41cbChris Lattner// 24160915146f4d35e12f10dcdaa155596fac79184daChris Lattnerbool llvm::InlineFunction(CallSite CS, InlineFunctionInfo &IFI) { 24280a38d245359cb0a3be8f78f5d7d911232886b9aChris Lattner Instruction *TheCall = CS.getInstruction(); 243e922c0201916e0b980ab3cfe91e1413e68d55647Owen Anderson LLVMContext &Context = TheCall->getContext(); 24480a38d245359cb0a3be8f78f5d7d911232886b9aChris Lattner assert(TheCall->getParent() && TheCall->getParent()->getParent() && 24580a38d245359cb0a3be8f78f5d7d911232886b9aChris Lattner "Instruction not in function!"); 246ca398dc3989d35e8516489fd163e012133bd41cbChris Lattner 24760915146f4d35e12f10dcdaa155596fac79184daChris Lattner // If IFI has any state in it, zap it before we fill it in. 24860915146f4d35e12f10dcdaa155596fac79184daChris Lattner IFI.reset(); 24960915146f4d35e12f10dcdaa155596fac79184daChris Lattner 25080a38d245359cb0a3be8f78f5d7d911232886b9aChris Lattner const Function *CalledFunc = CS.getCalledFunction(); 251ca398dc3989d35e8516489fd163e012133bd41cbChris Lattner if (CalledFunc == 0 || // Can't inline external function or indirect 2525cbf985dcbc89fba3208e7baf8b6f488b06d3ec9Reid Spencer CalledFunc->isDeclaration() || // call, or call to a vararg function! 2530623e90398153be61226ad19f1b40d3817874526Eric Christopher CalledFunc->getFunctionType()->isVarArg()) return false; 254ca398dc3989d35e8516489fd163e012133bd41cbChris Lattner 2551b49141821e98e4321bfe6234c7001c836b2a289Chris Lattner 256af9985c6b9d066cb70a0363fed699022d0ec196cChris Lattner // If the call to the callee is not a tail call, we must clear the 'tail' 2571b49141821e98e4321bfe6234c7001c836b2a289Chris Lattner // flags on any calls that we inline. 2581b49141821e98e4321bfe6234c7001c836b2a289Chris Lattner bool MustClearTailCallFlags = 259af9985c6b9d066cb70a0363fed699022d0ec196cChris Lattner !(isa<CallInst>(TheCall) && cast<CallInst>(TheCall)->isTailCall()); 2601b49141821e98e4321bfe6234c7001c836b2a289Chris Lattner 261f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands // If the call to the callee cannot throw, set the 'nounwind' flag on any 262f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands // calls that we inline. 263f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands bool MarkNoUnwind = CS.doesNotThrow(); 264f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands 26580a38d245359cb0a3be8f78f5d7d911232886b9aChris Lattner BasicBlock *OrigBB = TheCall->getParent(); 266ca398dc3989d35e8516489fd163e012133bd41cbChris Lattner Function *Caller = OrigBB->getParent(); 267ca398dc3989d35e8516489fd163e012133bd41cbChris Lattner 2680e13821c96937830ec817f08095c3cef1fdcac8dGordon Henriksen // GC poses two hazards to inlining, which only occur when the callee has GC: 2690e13821c96937830ec817f08095c3cef1fdcac8dGordon Henriksen // 1. If the caller has no GC, then the callee's GC must be propagated to the 2700e13821c96937830ec817f08095c3cef1fdcac8dGordon Henriksen // caller. 2710e13821c96937830ec817f08095c3cef1fdcac8dGordon Henriksen // 2. If the caller has a differing GC, it is invalid to inline. 2725eca075b74d62c621b160aa216b4cd50829a2cc7Gordon Henriksen if (CalledFunc->hasGC()) { 2735eca075b74d62c621b160aa216b4cd50829a2cc7Gordon Henriksen if (!Caller->hasGC()) 2745eca075b74d62c621b160aa216b4cd50829a2cc7Gordon Henriksen Caller->setGC(CalledFunc->getGC()); 2755eca075b74d62c621b160aa216b4cd50829a2cc7Gordon Henriksen else if (CalledFunc->getGC() != Caller->getGC()) 2760e13821c96937830ec817f08095c3cef1fdcac8dGordon Henriksen return false; 2770e13821c96937830ec817f08095c3cef1fdcac8dGordon Henriksen } 278a7212e58260f6d1ead0c4eec7af400cf6c0d289eDuncan Sands 2795052c911ec1be51ecb36e7f025c26412e9f1bfacChris Lattner // Get an iterator to the last basic block in the function, which will have 2805052c911ec1be51ecb36e7f025c26412e9f1bfacChris Lattner // the new function inlined after it. 2815052c911ec1be51ecb36e7f025c26412e9f1bfacChris Lattner // 2825052c911ec1be51ecb36e7f025c26412e9f1bfacChris Lattner Function::iterator LastBlock = &Caller->back(); 2835052c911ec1be51ecb36e7f025c26412e9f1bfacChris Lattner 2845e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner // Make sure to capture all of the return instructions from the cloned 2855e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner // function. 286ec1bea0d94372985a0a5eb283e644c6d0dd345dcChris Lattner SmallVector<ReturnInst*, 8> Returns; 287cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner ClonedCodeInfo InlinedFunctionInfo; 2880744f09efc53d3352ac1caffc61f6e8239201c3bDale Johannesen Function::iterator FirstNewBlock; 289f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands 29029d3dd8a64791031eea00ffbae51843dc9982df9Devang Patel { // Scope to destroy VMap after cloning. 2911ed219a9d2279ce5a5bbcf16d9b7ccc05cce638cRafael Espindola ValueToValueMapTy VMap; 2925b5bc3032f97cfa7bfa3e22282d3a9c1ed05eec6Chris Lattner 2939614fcc640eb628cc5dfddb277ebae9f6cb61014Dan Gohman assert(CalledFunc->arg_size() == CS.arg_size() && 2945e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner "No varargs calls can be inlined!"); 295a7212e58260f6d1ead0c4eec7af400cf6c0d289eDuncan Sands 296c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner // Calculate the vector of arguments to pass into the function cloner, which 297c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner // matches up the formal to the actual argument values. 2985e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner CallSite::arg_iterator AI = CS.arg_begin(); 299c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner unsigned ArgNo = 0; 300e4d5c441e04bdc00ccf1804744af670655123b07Chris Lattner for (Function::const_arg_iterator I = CalledFunc->arg_begin(), 301c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner E = CalledFunc->arg_end(); I != E; ++I, ++AI, ++ArgNo) { 302c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner Value *ActualArg = *AI; 303a7212e58260f6d1ead0c4eec7af400cf6c0d289eDuncan Sands 304d82375c1c43db7f823dd4660d3495e76566699e3Duncan Sands // When byval arguments actually inlined, we need to make the copy implied 305d82375c1c43db7f823dd4660d3495e76566699e3Duncan Sands // by them explicit. However, we don't do this if the callee is readonly 306d82375c1c43db7f823dd4660d3495e76566699e3Duncan Sands // or readnone, because the copy would be unneeded: the callee doesn't 307d82375c1c43db7f823dd4660d3495e76566699e3Duncan Sands // modify the struct. 3080598866c052147c31b808391f58434ce3dbfb838Devang Patel if (CalledFunc->paramHasAttr(ArgNo+1, Attribute::ByVal) && 309d82375c1c43db7f823dd4660d3495e76566699e3Duncan Sands !CalledFunc->onlyReadsMemory()) { 310c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner const Type *AggTy = cast<PointerType>(I->getType())->getElementType(); 3111d0be15f89cb5056e20e2d24faa8d6afb1573bcaOwen Anderson const Type *VoidPtrTy = 312ac53a0b272452013124bfc70480aea5e41b60f40Duncan Sands Type::getInt8PtrTy(Context); 313a7212e58260f6d1ead0c4eec7af400cf6c0d289eDuncan Sands 314c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner // Create the alloca. If we have TargetData, use nice alignment. 315c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner unsigned Align = 1; 31660915146f4d35e12f10dcdaa155596fac79184daChris Lattner if (IFI.TD) Align = IFI.TD->getPrefTypeAlignment(AggTy); 31750dead06ffc107edb7e84857baaeeb09039c631cOwen Anderson Value *NewAlloca = new AllocaInst(AggTy, 0, Align, 3189adc0abad3c3ed40a268ccbcee0c74cb9e1359feOwen Anderson I->getName(), 3199adc0abad3c3ed40a268ccbcee0c74cb9e1359feOwen Anderson &*Caller->begin()->begin()); 320c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner // Emit a memcpy. 32120adc9dc4650313f017b27d9818eb2176238113dMon P Wang const Type *Tys[3] = {VoidPtrTy, VoidPtrTy, Type::getInt64Ty(Context)}; 322c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner Function *MemCpyFn = Intrinsic::getDeclaration(Caller->getParent(), 323824b958e6fb1236e92e4d07f3acf18fca107cdc0Chris Lattner Intrinsic::memcpy, 32420adc9dc4650313f017b27d9818eb2176238113dMon P Wang Tys, 3); 325c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner Value *DestCast = new BitCastInst(NewAlloca, VoidPtrTy, "tmp", TheCall); 326c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner Value *SrcCast = new BitCastInst(*AI, VoidPtrTy, "tmp", TheCall); 327a7212e58260f6d1ead0c4eec7af400cf6c0d289eDuncan Sands 328c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner Value *Size; 32960915146f4d35e12f10dcdaa155596fac79184daChris Lattner if (IFI.TD == 0) 330baf3c404409d5e47b13984a7f95bfbd6d1f2e79eOwen Anderson Size = ConstantExpr::getSizeOf(AggTy); 331c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner else 3321d0be15f89cb5056e20e2d24faa8d6afb1573bcaOwen Anderson Size = ConstantInt::get(Type::getInt64Ty(Context), 33360915146f4d35e12f10dcdaa155596fac79184daChris Lattner IFI.TD->getTypeStoreSize(AggTy)); 334a7212e58260f6d1ead0c4eec7af400cf6c0d289eDuncan Sands 335c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner // Always generate a memcpy of alignment 1 here because we don't know 336c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner // the alignment of the src pointer. Other optimizations can infer 337c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner // better alignment. 338c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner Value *CallArgs[] = { 3391d0be15f89cb5056e20e2d24faa8d6afb1573bcaOwen Anderson DestCast, SrcCast, Size, 34020adc9dc4650313f017b27d9818eb2176238113dMon P Wang ConstantInt::get(Type::getInt32Ty(Context), 1), 341f601d6df6f43bb833461cbcee475c36998e6c259Benjamin Kramer ConstantInt::getFalse(Context) // isVolatile 342c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner }; 343c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner CallInst *TheMemCpy = 34420adc9dc4650313f017b27d9818eb2176238113dMon P Wang CallInst::Create(MemCpyFn, CallArgs, CallArgs+5, "", TheCall); 345a7212e58260f6d1ead0c4eec7af400cf6c0d289eDuncan Sands 346c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner // If we have a call graph, update it. 34760915146f4d35e12f10dcdaa155596fac79184daChris Lattner if (CallGraph *CG = IFI.CG) { 348c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner CallGraphNode *MemCpyCGN = CG->getOrInsertFunction(MemCpyFn); 349c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner CallGraphNode *CallerNode = (*CG)[Caller]; 350c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner CallerNode->addCalledFunction(TheMemCpy, MemCpyCGN); 351c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner } 352a7212e58260f6d1ead0c4eec7af400cf6c0d289eDuncan Sands 353c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner // Uses of the argument in the function should use our new alloca 354c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner // instead. 355c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner ActualArg = NewAlloca; 3562914ba6ec793e2bb0e9ca5891af1d29ee2fee28eDuncan Sands 3572914ba6ec793e2bb0e9ca5891af1d29ee2fee28eDuncan Sands // Calls that we inline may use the new alloca, so we need to clear 3582914ba6ec793e2bb0e9ca5891af1d29ee2fee28eDuncan Sands // their 'tail' flags. 3592914ba6ec793e2bb0e9ca5891af1d29ee2fee28eDuncan Sands MustClearTailCallFlags = true; 360c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner } 361a7212e58260f6d1ead0c4eec7af400cf6c0d289eDuncan Sands 36229d3dd8a64791031eea00ffbae51843dc9982df9Devang Patel VMap[I] = ActualArg; 363c93adca35856d0eaae088e52ba30cfefbd7ad910Chris Lattner } 364fd93908ae8b9684fe71c239e3c6cfe13ff6a2663Misha Brukman 3655b5bc3032f97cfa7bfa3e22282d3a9c1ed05eec6Chris Lattner // We want the inliner to prune the code as it copies. We would LOVE to 3665b5bc3032f97cfa7bfa3e22282d3a9c1ed05eec6Chris Lattner // have no dead or constant instructions leftover after inlining occurs 3675b5bc3032f97cfa7bfa3e22282d3a9c1ed05eec6Chris Lattner // (which can happen, e.g., because an argument was constant), but we'll be 3685b5bc3032f97cfa7bfa3e22282d3a9c1ed05eec6Chris Lattner // happy with whatever the cloner can do. 3696cb8c23db1c3becdce6dfbf1b7f1677faca4251eDan Gohman CloneAndPruneFunctionInto(Caller, CalledFunc, VMap, 3706cb8c23db1c3becdce6dfbf1b7f1677faca4251eDan Gohman /*ModuleLevelChanges=*/false, Returns, ".i", 37160915146f4d35e12f10dcdaa155596fac79184daChris Lattner &InlinedFunctionInfo, IFI.TD, TheCall); 372a7212e58260f6d1ead0c4eec7af400cf6c0d289eDuncan Sands 373d85340f4ec587e22b0239617f3b747a6df113894Chris Lattner // Remember the first block that is newly cloned over. 374d85340f4ec587e22b0239617f3b747a6df113894Chris Lattner FirstNewBlock = LastBlock; ++FirstNewBlock; 375a7212e58260f6d1ead0c4eec7af400cf6c0d289eDuncan Sands 376d85340f4ec587e22b0239617f3b747a6df113894Chris Lattner // Update the callgraph if requested. 37760915146f4d35e12f10dcdaa155596fac79184daChris Lattner if (IFI.CG) 37829d3dd8a64791031eea00ffbae51843dc9982df9Devang Patel UpdateCallGraphAfterInlining(CS, FirstNewBlock, VMap, IFI); 379fd93908ae8b9684fe71c239e3c6cfe13ff6a2663Misha Brukman } 380a7212e58260f6d1ead0c4eec7af400cf6c0d289eDuncan Sands 381ca398dc3989d35e8516489fd163e012133bd41cbChris Lattner // If there are any alloca instructions in the block that used to be the entry 382ca398dc3989d35e8516489fd163e012133bd41cbChris Lattner // block for the callee, move them to the entry block of the caller. First 383ca398dc3989d35e8516489fd163e012133bd41cbChris Lattner // calculate which instruction they should be inserted before. We insert the 384ca398dc3989d35e8516489fd163e012133bd41cbChris Lattner // instructions at the end of the current alloca list. 385ca398dc3989d35e8516489fd163e012133bd41cbChris Lattner // 38621f20558d629f7ff8f64c20746d890d29328a544Chris Lattner { 38780a38d245359cb0a3be8f78f5d7d911232886b9aChris Lattner BasicBlock::iterator InsertPoint = Caller->begin()->begin(); 3885e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner for (BasicBlock::iterator I = FirstNewBlock->begin(), 389135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner E = FirstNewBlock->end(); I != E; ) { 390135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner AllocaInst *AI = dyn_cast<AllocaInst>(I++); 391135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner if (AI == 0) continue; 392135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 393135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // If the alloca is now dead, remove it. This often occurs due to code 394135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // specialization. 395135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner if (AI->use_empty()) { 396135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner AI->eraseFromParent(); 397135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner continue; 39833bb3c8be355d179ece8e751f6e0f0978d0dd038Chris Lattner } 399135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 400135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner if (!isa<Constant>(AI->getArraySize())) 401135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner continue; 402135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 40339add23dc54a1580983b1901384688d6622daa3bChris Lattner // Keep track of the static allocas that we inline into the caller. 40460915146f4d35e12f10dcdaa155596fac79184daChris Lattner IFI.StaticAllocas.push_back(AI); 4058f2718fbef6177966ff807af0732eb2431bd9a5fChris Lattner 406135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // Scan for the block of allocas that we can move over, and move them 407135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // all at once. 408135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner while (isa<AllocaInst>(I) && 4098f2718fbef6177966ff807af0732eb2431bd9a5fChris Lattner isa<Constant>(cast<AllocaInst>(I)->getArraySize())) { 41060915146f4d35e12f10dcdaa155596fac79184daChris Lattner IFI.StaticAllocas.push_back(cast<AllocaInst>(I)); 411135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner ++I; 4128f2718fbef6177966ff807af0732eb2431bd9a5fChris Lattner } 413135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner 414135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // Transfer all of the allocas over in a block. Using splice means 415135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // that the instructions aren't removed from the symbol table, then 416135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner // reinserted. 417135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner Caller->getEntryBlock().getInstList().splice(InsertPoint, 418135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner FirstNewBlock->getInstList(), 419135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner AI, I); 420135755dae4c3fa8003b76150689d5064aa4612eeChris Lattner } 42180a38d245359cb0a3be8f78f5d7d911232886b9aChris Lattner } 42280a38d245359cb0a3be8f78f5d7d911232886b9aChris Lattner 423bf229f488a7541abd979cc3fbe9c3ce1c100e5c0Chris Lattner // If the inlined code contained dynamic alloca instructions, wrap the inlined 424bf229f488a7541abd979cc3fbe9c3ce1c100e5c0Chris Lattner // code with llvm.stacksave/llvm.stackrestore intrinsics. 425bf229f488a7541abd979cc3fbe9c3ce1c100e5c0Chris Lattner if (InlinedFunctionInfo.ContainsDynamicAllocas) { 426bf229f488a7541abd979cc3fbe9c3ce1c100e5c0Chris Lattner Module *M = Caller->getParent(); 427bf229f488a7541abd979cc3fbe9c3ce1c100e5c0Chris Lattner // Get the two intrinsics we care about. 4286128df525501c333a650d097703c18d7e878f5e8Chris Lattner Function *StackSave = Intrinsic::getDeclaration(M, Intrinsic::stacksave); 4296128df525501c333a650d097703c18d7e878f5e8Chris Lattner Function *StackRestore=Intrinsic::getDeclaration(M,Intrinsic::stackrestore); 430d85340f4ec587e22b0239617f3b747a6df113894Chris Lattner 431d85340f4ec587e22b0239617f3b747a6df113894Chris Lattner // If we are preserving the callgraph, add edges to the stacksave/restore 432d85340f4ec587e22b0239617f3b747a6df113894Chris Lattner // functions for the calls we insert. 43321ba23d0d88cff57dcdf104cd6914dabcbc68131Chris Lattner CallGraphNode *StackSaveCGN = 0, *StackRestoreCGN = 0, *CallerNode = 0; 43460915146f4d35e12f10dcdaa155596fac79184daChris Lattner if (CallGraph *CG = IFI.CG) { 4356128df525501c333a650d097703c18d7e878f5e8Chris Lattner StackSaveCGN = CG->getOrInsertFunction(StackSave); 4366128df525501c333a650d097703c18d7e878f5e8Chris Lattner StackRestoreCGN = CG->getOrInsertFunction(StackRestore); 437d85340f4ec587e22b0239617f3b747a6df113894Chris Lattner CallerNode = (*CG)[Caller]; 438d85340f4ec587e22b0239617f3b747a6df113894Chris Lattner } 439a7212e58260f6d1ead0c4eec7af400cf6c0d289eDuncan Sands 440bf229f488a7541abd979cc3fbe9c3ce1c100e5c0Chris Lattner // Insert the llvm.stacksave. 441a7212e58260f6d1ead0c4eec7af400cf6c0d289eDuncan Sands CallInst *SavedPtr = CallInst::Create(StackSave, "savedstack", 442051a950000e21935165db56695e35bade668193bGabor Greif FirstNewBlock->begin()); 44360915146f4d35e12f10dcdaa155596fac79184daChris Lattner if (IFI.CG) CallerNode->addCalledFunction(SavedPtr, StackSaveCGN); 444a7212e58260f6d1ead0c4eec7af400cf6c0d289eDuncan Sands 445bf229f488a7541abd979cc3fbe9c3ce1c100e5c0Chris Lattner // Insert a call to llvm.stackrestore before any return instructions in the 446bf229f488a7541abd979cc3fbe9c3ce1c100e5c0Chris Lattner // inlined function. 447d85340f4ec587e22b0239617f3b747a6df113894Chris Lattner for (unsigned i = 0, e = Returns.size(); i != e; ++i) { 448051a950000e21935165db56695e35bade668193bGabor Greif CallInst *CI = CallInst::Create(StackRestore, SavedPtr, "", Returns[i]); 44960915146f4d35e12f10dcdaa155596fac79184daChris Lattner if (IFI.CG) CallerNode->addCalledFunction(CI, StackRestoreCGN); 450d85340f4ec587e22b0239617f3b747a6df113894Chris Lattner } 451468fb1df7db466e5682ee44341c3990b599e8d6aChris Lattner 452468fb1df7db466e5682ee44341c3990b599e8d6aChris Lattner // Count the number of StackRestore calls we insert. 453468fb1df7db466e5682ee44341c3990b599e8d6aChris Lattner unsigned NumStackRestores = Returns.size(); 454a7212e58260f6d1ead0c4eec7af400cf6c0d289eDuncan Sands 455bf229f488a7541abd979cc3fbe9c3ce1c100e5c0Chris Lattner // If we are inlining an invoke instruction, insert restores before each 456bf229f488a7541abd979cc3fbe9c3ce1c100e5c0Chris Lattner // unwind. These unwinds will be rewritten into branches later. 457bf229f488a7541abd979cc3fbe9c3ce1c100e5c0Chris Lattner if (InlinedFunctionInfo.ContainsUnwinds && isa<InvokeInst>(TheCall)) { 458bf229f488a7541abd979cc3fbe9c3ce1c100e5c0Chris Lattner for (Function::iterator BB = FirstNewBlock, E = Caller->end(); 459bf229f488a7541abd979cc3fbe9c3ce1c100e5c0Chris Lattner BB != E; ++BB) 460468fb1df7db466e5682ee44341c3990b599e8d6aChris Lattner if (UnwindInst *UI = dyn_cast<UnwindInst>(BB->getTerminator())) { 4616128df525501c333a650d097703c18d7e878f5e8Chris Lattner CallInst *CI = CallInst::Create(StackRestore, SavedPtr, "", UI); 46260915146f4d35e12f10dcdaa155596fac79184daChris Lattner if (IFI.CG) CallerNode->addCalledFunction(CI, StackRestoreCGN); 463468fb1df7db466e5682ee44341c3990b599e8d6aChris Lattner ++NumStackRestores; 464468fb1df7db466e5682ee44341c3990b599e8d6aChris Lattner } 465468fb1df7db466e5682ee44341c3990b599e8d6aChris Lattner } 466bf229f488a7541abd979cc3fbe9c3ce1c100e5c0Chris Lattner } 467bf229f488a7541abd979cc3fbe9c3ce1c100e5c0Chris Lattner 468a7212e58260f6d1ead0c4eec7af400cf6c0d289eDuncan Sands // If we are inlining tail call instruction through a call site that isn't 4691fdf4a859f03ce5aa4ce9acba29ce321c847388eChris Lattner // marked 'tail', we must remove the tail marker for any calls in the inlined 470f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands // code. Also, calls inlined through a 'nounwind' call site should be marked 471f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands // 'nounwind'. 472f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands if (InlinedFunctionInfo.ContainsCalls && 473f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands (MustClearTailCallFlags || MarkNoUnwind)) { 4741b49141821e98e4321bfe6234c7001c836b2a289Chris Lattner for (Function::iterator BB = FirstNewBlock, E = Caller->end(); 4751b49141821e98e4321bfe6234c7001c836b2a289Chris Lattner BB != E; ++BB) 4761b49141821e98e4321bfe6234c7001c836b2a289Chris Lattner for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E; ++I) 477f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands if (CallInst *CI = dyn_cast<CallInst>(I)) { 478f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands if (MustClearTailCallFlags) 479f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands CI->setTailCall(false); 480f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands if (MarkNoUnwind) 481f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands CI->setDoesNotThrow(); 482f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands } 4831b49141821e98e4321bfe6234c7001c836b2a289Chris Lattner } 4841b49141821e98e4321bfe6234c7001c836b2a289Chris Lattner 485f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands // If we are inlining through a 'nounwind' call site then any inlined 'unwind' 486f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands // instructions are unreachable. 487f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands if (InlinedFunctionInfo.ContainsUnwinds && MarkNoUnwind) 488f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands for (Function::iterator BB = FirstNewBlock, E = Caller->end(); 489f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands BB != E; ++BB) { 490f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands TerminatorInst *Term = BB->getTerminator(); 491f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands if (isa<UnwindInst>(Term)) { 4921d0be15f89cb5056e20e2d24faa8d6afb1573bcaOwen Anderson new UnreachableInst(Context, Term); 493f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands BB->getInstList().erase(Term); 494f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands } 495f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands } 496f0c3354d998507515ab39e26b5292ea0ceb06aefDuncan Sands 4975e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner // If we are inlining for an invoke instruction, we must make sure to rewrite 4985e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner // any inlined 'unwind' instructions into branches to the invoke exception 4995e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner // destination, and call instructions into invoke instructions. 500cd4d339ec187182c9abc22b80560349f8ba5010fChris Lattner if (InvokeInst *II = dyn_cast<InvokeInst>(TheCall)) 50181dfb3885252fbf621b080827a080099864415f8Chris Lattner HandleInlinedInvoke(II, FirstNewBlock, InlinedFunctionInfo); 5025e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner 50344a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner // If we cloned in _exactly one_ basic block, and if that block ends in a 50444a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner // return instruction, we splice the body of the inlined callee directly into 50544a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner // the calling basic block. 50644a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner if (Returns.size() == 1 && std::distance(FirstNewBlock, Caller->end()) == 1) { 50744a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner // Move all of the instructions right before the call. 50844a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner OrigBB->getInstList().splice(TheCall, FirstNewBlock->getInstList(), 50944a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner FirstNewBlock->begin(), FirstNewBlock->end()); 51044a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner // Remove the cloned basic block. 51144a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner Caller->getBasicBlockList().pop_back(); 512fd93908ae8b9684fe71c239e3c6cfe13ff6a2663Misha Brukman 51344a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner // If the call site was an invoke instruction, add a branch to the normal 51444a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner // destination. 51544a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner if (InvokeInst *II = dyn_cast<InvokeInst>(TheCall)) 516051a950000e21935165db56695e35bade668193bGabor Greif BranchInst::Create(II->getNormalDest(), TheCall); 51744a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner 51844a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner // If the return instruction returned a value, replace uses of the call with 51944a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner // uses of the returned value. 520dc00d42bb18a6748f43c365d9bd30c1ed0e800acDevang Patel if (!TheCall->use_empty()) { 521dc00d42bb18a6748f43c365d9bd30c1ed0e800acDevang Patel ReturnInst *R = Returns[0]; 5225877ad7e90de2179c15914ff9e8f1c72152cac30Eli Friedman if (TheCall == R->getReturnValue()) 5239e9a0d5fc26878e51a58a8b57900fcbf952c2691Owen Anderson TheCall->replaceAllUsesWith(UndefValue::get(TheCall->getType())); 5245877ad7e90de2179c15914ff9e8f1c72152cac30Eli Friedman else 5255877ad7e90de2179c15914ff9e8f1c72152cac30Eli Friedman TheCall->replaceAllUsesWith(R->getReturnValue()); 526dc00d42bb18a6748f43c365d9bd30c1ed0e800acDevang Patel } 52744a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner // Since we are now done with the Call/Invoke, we can delete it. 5281adec83ae84031bfa9f0bf209c5ee6c64906a1ffDan Gohman TheCall->eraseFromParent(); 52944a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner 53044a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner // Since we are now done with the return instruction, delete it also. 5311adec83ae84031bfa9f0bf209c5ee6c64906a1ffDan Gohman Returns[0]->eraseFromParent(); 53244a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner 53344a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner // We are now done with the inlining. 53444a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner return true; 53544a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner } 53644a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner 53744a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner // Otherwise, we have the normal case, of more than one block to inline or 53844a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner // multiple return sites. 53944a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner 5405e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner // We want to clone the entire callee function into the hole between the 5415e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner // "starter" and "ender" blocks. How we accomplish this depends on whether 5425e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner // this is an invoke instruction or a call instruction. 5435e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner BasicBlock *AfterCallBB; 5445e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner if (InvokeInst *II = dyn_cast<InvokeInst>(TheCall)) { 545fd93908ae8b9684fe71c239e3c6cfe13ff6a2663Misha Brukman 5465e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner // Add an unconditional branch to make this look like the CallInst case... 547051a950000e21935165db56695e35bade668193bGabor Greif BranchInst *NewBr = BranchInst::Create(II->getNormalDest(), TheCall); 548fd93908ae8b9684fe71c239e3c6cfe13ff6a2663Misha Brukman 5495e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner // Split the basic block. This guarantees that no PHI nodes will have to be 5505e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner // updated due to new incoming edges, and make the invoke case more 5515e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner // symmetric to the call case. 5525e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner AfterCallBB = OrigBB->splitBasicBlock(NewBr, 553284d1b88273eb1967c8faef407f1167791c760e0Chris Lattner CalledFunc->getName()+".exit"); 554fd93908ae8b9684fe71c239e3c6cfe13ff6a2663Misha Brukman 5555e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner } else { // It's a call 55644a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner // If this is a call instruction, we need to split the basic block that 55744a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner // the call lives in. 5585e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner // 5595e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner AfterCallBB = OrigBB->splitBasicBlock(TheCall, 560284d1b88273eb1967c8faef407f1167791c760e0Chris Lattner CalledFunc->getName()+".exit"); 5615e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner } 5625e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner 56344a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner // Change the branch that used to go to AfterCallBB to branch to the first 56444a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner // basic block of the inlined function. 56544a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner // 56644a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner TerminatorInst *Br = OrigBB->getTerminator(); 567fd93908ae8b9684fe71c239e3c6cfe13ff6a2663Misha Brukman assert(Br && Br->getOpcode() == Instruction::Br && 56844a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner "splitBasicBlock broken!"); 56944a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner Br->setOperand(0, FirstNewBlock); 57044a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner 57144a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner 57244a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner // Now that the function is correct, make it a little bit nicer. In 57344a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner // particular, move the basic blocks inserted from the end of the function 57444a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner // into the space made by splitting the source basic block. 57544a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner Caller->getBasicBlockList().splice(AfterCallBB, Caller->getBasicBlockList(), 57644a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner FirstNewBlock, Caller->end()); 57744a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner 5785e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner // Handle all of the return instructions that we just cloned in, and eliminate 5795e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner // any users of the original call/invoke instruction. 580b8f198af1b62f2ed48dcb914973a9d211dcba38bDevang Patel const Type *RTy = CalledFunc->getReturnType(); 5812c31750cd0ebdc83a890ace97dbb6249b3abe44eDan Gohman 5826fb881c036c32728c4a128d81b6083457e534e09Duncan Sands PHINode *PHI = 0; 583fc74abfba5128544a750fce22fdf13eb0403e3ceDan Gohman if (Returns.size() > 1) { 5845e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner // The PHI node should go at the front of the new basic block to merge all 5855e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner // possible incoming values. 5865e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner if (!TheCall->use_empty()) { 587fc74abfba5128544a750fce22fdf13eb0403e3ceDan Gohman PHI = PHINode::Create(RTy, TheCall->getName(), 588fc74abfba5128544a750fce22fdf13eb0403e3ceDan Gohman AfterCallBB->begin()); 589fc74abfba5128544a750fce22fdf13eb0403e3ceDan Gohman // Anything that used the result of the function call should now use the 590fc74abfba5128544a750fce22fdf13eb0403e3ceDan Gohman // PHI node as their operand. 591a7212e58260f6d1ead0c4eec7af400cf6c0d289eDuncan Sands TheCall->replaceAllUsesWith(PHI); 5925e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner } 593fd93908ae8b9684fe71c239e3c6cfe13ff6a2663Misha Brukman 594c478e52bf4c12691037856ee103c66946afeab6cGabor Greif // Loop over all of the return instructions adding entries to the PHI node 595c478e52bf4c12691037856ee103c66946afeab6cGabor Greif // as appropriate. 596fc74abfba5128544a750fce22fdf13eb0403e3ceDan Gohman if (PHI) { 597fc74abfba5128544a750fce22fdf13eb0403e3ceDan Gohman for (unsigned i = 0, e = Returns.size(); i != e; ++i) { 598fc74abfba5128544a750fce22fdf13eb0403e3ceDan Gohman ReturnInst *RI = Returns[i]; 599fc74abfba5128544a750fce22fdf13eb0403e3ceDan Gohman assert(RI->getReturnValue()->getType() == PHI->getType() && 600fc74abfba5128544a750fce22fdf13eb0403e3ceDan Gohman "Ret value not consistent in function!"); 601fc74abfba5128544a750fce22fdf13eb0403e3ceDan Gohman PHI->addIncoming(RI->getReturnValue(), RI->getParent()); 6025e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner } 60312a466b9d0e27be453cfa05cff18acc9d7c1cfbaDevang Patel } 604fd93908ae8b9684fe71c239e3c6cfe13ff6a2663Misha Brukman 605c581acbbba3cb1af6a08e17314b26344333f9267Chris Lattner 606de62aeaec49ddcf4a4c61fbbb3a22d3a4dd448f0Gabor Greif // Add a branch to the merge points and remove return instructions. 60712a466b9d0e27be453cfa05cff18acc9d7c1cfbaDevang Patel for (unsigned i = 0, e = Returns.size(); i != e; ++i) { 60812a466b9d0e27be453cfa05cff18acc9d7c1cfbaDevang Patel ReturnInst *RI = Returns[i]; 6090744f09efc53d3352ac1caffc61f6e8239201c3bDale Johannesen BranchInst::Create(AfterCallBB, RI); 610b8f198af1b62f2ed48dcb914973a9d211dcba38bDevang Patel RI->eraseFromParent(); 6115e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner } 612b8f198af1b62f2ed48dcb914973a9d211dcba38bDevang Patel } else if (!Returns.empty()) { 613b8f198af1b62f2ed48dcb914973a9d211dcba38bDevang Patel // Otherwise, if there is exactly one return value, just replace anything 614b8f198af1b62f2ed48dcb914973a9d211dcba38bDevang Patel // using the return value of the call with the computed value. 6155877ad7e90de2179c15914ff9e8f1c72152cac30Eli Friedman if (!TheCall->use_empty()) { 6165877ad7e90de2179c15914ff9e8f1c72152cac30Eli Friedman if (TheCall == Returns[0]->getReturnValue()) 6179e9a0d5fc26878e51a58a8b57900fcbf952c2691Owen Anderson TheCall->replaceAllUsesWith(UndefValue::get(TheCall->getType())); 6185877ad7e90de2179c15914ff9e8f1c72152cac30Eli Friedman else 6195877ad7e90de2179c15914ff9e8f1c72152cac30Eli Friedman TheCall->replaceAllUsesWith(Returns[0]->getReturnValue()); 6205877ad7e90de2179c15914ff9e8f1c72152cac30Eli Friedman } 621a7212e58260f6d1ead0c4eec7af400cf6c0d289eDuncan Sands 622b8f198af1b62f2ed48dcb914973a9d211dcba38bDevang Patel // Splice the code from the return block into the block that it will return 623b8f198af1b62f2ed48dcb914973a9d211dcba38bDevang Patel // to, which contains the code that was after the call. 624b8f198af1b62f2ed48dcb914973a9d211dcba38bDevang Patel BasicBlock *ReturnBB = Returns[0]->getParent(); 625b8f198af1b62f2ed48dcb914973a9d211dcba38bDevang Patel AfterCallBB->getInstList().splice(AfterCallBB->begin(), 626b8f198af1b62f2ed48dcb914973a9d211dcba38bDevang Patel ReturnBB->getInstList()); 627a7212e58260f6d1ead0c4eec7af400cf6c0d289eDuncan Sands 628b8f198af1b62f2ed48dcb914973a9d211dcba38bDevang Patel // Update PHI nodes that use the ReturnBB to use the AfterCallBB. 629b8f198af1b62f2ed48dcb914973a9d211dcba38bDevang Patel ReturnBB->replaceAllUsesWith(AfterCallBB); 630a7212e58260f6d1ead0c4eec7af400cf6c0d289eDuncan Sands 631b8f198af1b62f2ed48dcb914973a9d211dcba38bDevang Patel // Delete the return instruction now and empty ReturnBB now. 632b8f198af1b62f2ed48dcb914973a9d211dcba38bDevang Patel Returns[0]->eraseFromParent(); 633b8f198af1b62f2ed48dcb914973a9d211dcba38bDevang Patel ReturnBB->eraseFromParent(); 6343787e765facfad5ea62753922d940bcdd52afd57Chris Lattner } else if (!TheCall->use_empty()) { 6353787e765facfad5ea62753922d940bcdd52afd57Chris Lattner // No returns, but something is using the return value of the call. Just 6363787e765facfad5ea62753922d940bcdd52afd57Chris Lattner // nuke the result. 6379e9a0d5fc26878e51a58a8b57900fcbf952c2691Owen Anderson TheCall->replaceAllUsesWith(UndefValue::get(TheCall->getType())); 6385e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner } 639fd93908ae8b9684fe71c239e3c6cfe13ff6a2663Misha Brukman 6405e923dee6024248f58fa83a7c7299437f44f0d1aChris Lattner // Since we are now done with the Call/Invoke, we can delete it. 6413787e765facfad5ea62753922d940bcdd52afd57Chris Lattner TheCall->eraseFromParent(); 642ca398dc3989d35e8516489fd163e012133bd41cbChris Lattner 6437152c237b46a920b29d5605af934766b8f9a07a1Chris Lattner // We should always be able to fold the entry block of the function into the 6447152c237b46a920b29d5605af934766b8f9a07a1Chris Lattner // single predecessor of the block... 645cd01ae5c7071fb99a665b2bbea7428d769792ab8Chris Lattner assert(cast<BranchInst>(Br)->isUnconditional() && "splitBasicBlock broken!"); 6467152c237b46a920b29d5605af934766b8f9a07a1Chris Lattner BasicBlock *CalleeEntry = cast<BranchInst>(Br)->getSuccessor(0); 64744a6807f4f785ecdd96b3aa67dad056677131b98Chris Lattner 648cd01ae5c7071fb99a665b2bbea7428d769792ab8Chris Lattner // Splice the code entry block into calling block, right before the 649cd01ae5c7071fb99a665b2bbea7428d769792ab8Chris Lattner // unconditional branch. 650cd01ae5c7071fb99a665b2bbea7428d769792ab8Chris Lattner OrigBB->getInstList().splice(Br, CalleeEntry->getInstList()); 651cd01ae5c7071fb99a665b2bbea7428d769792ab8Chris Lattner CalleeEntry->replaceAllUsesWith(OrigBB); // Update PHI nodes 652cd01ae5c7071fb99a665b2bbea7428d769792ab8Chris Lattner 653cd01ae5c7071fb99a665b2bbea7428d769792ab8Chris Lattner // Remove the unconditional branch. 654cd01ae5c7071fb99a665b2bbea7428d769792ab8Chris Lattner OrigBB->getInstList().erase(Br); 655cd01ae5c7071fb99a665b2bbea7428d769792ab8Chris Lattner 656cd01ae5c7071fb99a665b2bbea7428d769792ab8Chris Lattner // Now we can remove the CalleeEntry block, which is now empty. 657cd01ae5c7071fb99a665b2bbea7428d769792ab8Chris Lattner Caller->getBasicBlockList().erase(CalleeEntry); 658a7212e58260f6d1ead0c4eec7af400cf6c0d289eDuncan Sands 6596fb881c036c32728c4a128d81b6083457e534e09Duncan Sands // If we inserted a phi node, check to see if it has a single value (e.g. all 6606fb881c036c32728c4a128d81b6083457e534e09Duncan Sands // the entries are the same or undef). If so, remove the PHI so it doesn't 6616fb881c036c32728c4a128d81b6083457e534e09Duncan Sands // block other optimizations. 6626fb881c036c32728c4a128d81b6083457e534e09Duncan Sands if (PHI) 6636fb881c036c32728c4a128d81b6083457e534e09Duncan Sands if (Value *V = SimplifyInstruction(PHI, IFI.TD)) { 6646fb881c036c32728c4a128d81b6083457e534e09Duncan Sands PHI->replaceAllUsesWith(V); 6656fb881c036c32728c4a128d81b6083457e534e09Duncan Sands PHI->eraseFromParent(); 6666fb881c036c32728c4a128d81b6083457e534e09Duncan Sands } 6676fb881c036c32728c4a128d81b6083457e534e09Duncan Sands 668ca398dc3989d35e8516489fd163e012133bd41cbChris Lattner return true; 669ca398dc3989d35e8516489fd163e012133bd41cbChris Lattner} 670