ScalarReplAggregates.cpp revision 394d1f1948c1b5c9e902059104b08a4837dfbbee
1ed7b41ea90a17c826f195acbc456c4bb733113d6Chris Lattner//===- ScalarReplAggregates.cpp - Scalar Replacement of Aggregates --------===// 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//===----------------------------------------------------------------------===// 9ed7b41ea90a17c826f195acbc456c4bb733113d6Chris Lattner// 10ed7b41ea90a17c826f195acbc456c4bb733113d6Chris Lattner// This transformation implements the well known scalar replacement of 11ed7b41ea90a17c826f195acbc456c4bb733113d6Chris Lattner// aggregates transformation. This xform breaks up alloca instructions of 12ed7b41ea90a17c826f195acbc456c4bb733113d6Chris Lattner// aggregate type (structure or array) into individual alloca instructions for 1338aec325604635380421a27e39ab06d55ed2458dChris Lattner// each member (if possible). Then, if possible, it transforms the individual 1438aec325604635380421a27e39ab06d55ed2458dChris Lattner// alloca instructions into nice clean scalar SSA form. 1538aec325604635380421a27e39ab06d55ed2458dChris Lattner// 1638aec325604635380421a27e39ab06d55ed2458dChris Lattner// This combines a simple SRoA algorithm with the Mem2Reg algorithm because 1738aec325604635380421a27e39ab06d55ed2458dChris Lattner// often interact, especially for C++ programs. As such, iterating between 1838aec325604635380421a27e39ab06d55ed2458dChris Lattner// SRoA, then Mem2Reg until we run out of things to promote works well. 19ed7b41ea90a17c826f195acbc456c4bb733113d6Chris Lattner// 20ed7b41ea90a17c826f195acbc456c4bb733113d6Chris Lattner//===----------------------------------------------------------------------===// 21ed7b41ea90a17c826f195acbc456c4bb733113d6Chris Lattner 220e5f499638c8d277b9dc4a4385712177c53b5681Chris Lattner#define DEBUG_TYPE "scalarrepl" 23ed7b41ea90a17c826f195acbc456c4bb733113d6Chris Lattner#include "llvm/Transforms/Scalar.h" 2438aec325604635380421a27e39ab06d55ed2458dChris Lattner#include "llvm/Constants.h" 2538aec325604635380421a27e39ab06d55ed2458dChris Lattner#include "llvm/DerivedTypes.h" 26ed7b41ea90a17c826f195acbc456c4bb733113d6Chris Lattner#include "llvm/Function.h" 2779b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner#include "llvm/GlobalVariable.h" 28d8e1eea678833cc2b15e4ea69a5a403ba9c3b013Misha Brukman#include "llvm/Instructions.h" 29372dda8881c7a32a6f5ce0f76a713e3a9ef46ea1Chris Lattner#include "llvm/IntrinsicInst.h" 30fa5cbd6d0fbda23fd669c8718e07b19001b2d21aOwen Anderson#include "llvm/LLVMContext.h" 3172eaa0e5eb345a8483608675b86dfcfa465c784cChris Lattner#include "llvm/Module.h" 32372dda8881c7a32a6f5ce0f76a713e3a9ef46ea1Chris Lattner#include "llvm/Pass.h" 33c827939046670a9800659b83e2048f1d3a79a531Cameron Zwarich#include "llvm/Analysis/DIBuilder.h" 34b1686c32fc694636cbf15a59b23b2a741b65ecf4Cameron Zwarich#include "llvm/Analysis/Dominators.h" 35c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner#include "llvm/Analysis/Loads.h" 365034dd318a9dfa0dc45a3ac01e58e60f2aa2498dDan Gohman#include "llvm/Analysis/ValueTracking.h" 3738aec325604635380421a27e39ab06d55ed2458dChris Lattner#include "llvm/Target/TargetData.h" 3838aec325604635380421a27e39ab06d55ed2458dChris Lattner#include "llvm/Transforms/Utils/PromoteMemToReg.h" 394afc90dacf309999d8b7f6c2b4b0c56af346bab5Devang Patel#include "llvm/Transforms/Utils/Local.h" 40e0a1a5ba91df6817f9ffae7af65ed0bda66f7620Chris Lattner#include "llvm/Transforms/Utils/SSAUpdater.h" 41a9be1df6d7a9b5a07253d83a634ae5876e7e5550Chris Lattner#include "llvm/Support/CallSite.h" 429525528a7dc5462b6374d38c81ba5c07b11741feChris Lattner#include "llvm/Support/Debug.h" 437d696d80409aad20bb5da0fc4eccab941dd371d4Torok Edwin#include "llvm/Support/ErrorHandling.h" 44a188894d67a3cc2516b25aae9b3cbdbff4b0babeChris Lattner#include "llvm/Support/GetElementPtrTypeIterator.h" 4565a650291d01638853aaf1e80fcc2fc86a785957Chris Lattner#include "llvm/Support/IRBuilder.h" 46a188894d67a3cc2516b25aae9b3cbdbff4b0babeChris Lattner#include "llvm/Support/MathExtras.h" 47bdff548e4dd577a72094d57b282de4e765643b96Chris Lattner#include "llvm/Support/raw_ostream.h" 48c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner#include "llvm/ADT/SetVector.h" 491ccd185cb49d81465a2901622e58ceae046d1d83Chris Lattner#include "llvm/ADT/SmallVector.h" 50551ccae044b0ff658fe629dd67edd5ffe75d10e8Reid Spencer#include "llvm/ADT/Statistic.h" 51d8664730942beb911327336d1f9db8e7efcd6813Chris Lattnerusing namespace llvm; 52d0fde30ce850b78371fd1386338350591f9ff494Brian Gaeke 530e5f499638c8d277b9dc4a4385712177c53b5681Chris LattnerSTATISTIC(NumReplaced, "Number of allocas broken up"); 540e5f499638c8d277b9dc4a4385712177c53b5681Chris LattnerSTATISTIC(NumPromoted, "Number of allocas promoted"); 55c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris LattnerSTATISTIC(NumAdjusted, "Number of scalar allocas adjusted to allow promotion"); 560e5f499638c8d277b9dc4a4385712177c53b5681Chris LattnerSTATISTIC(NumConverted, "Number of aggregates converted to scalar"); 5779b3bd395dc3303cde65e18e0524ed2f70268c99Chris LattnerSTATISTIC(NumGlobals, "Number of allocas copied from constant global"); 58ed7b41ea90a17c826f195acbc456c4bb733113d6Chris Lattner 590e5f499638c8d277b9dc4a4385712177c53b5681Chris Lattnernamespace { 603e8b6631e67e01e4960a7ba4668a50c596607473Chris Lattner struct SROA : public FunctionPass { 61b1686c32fc694636cbf15a59b23b2a741b65ecf4Cameron Zwarich SROA(int T, bool hasDT, char &ID) 62b1686c32fc694636cbf15a59b23b2a741b65ecf4Cameron Zwarich : FunctionPass(ID), HasDomTree(hasDT) { 63ff366850aa9956e167e78d4f5b57aae10d8c5779Devang Patel if (T == -1) 64b0e71edb6b33f822e001500dac90acf95faacea8Chris Lattner SRThreshold = 128; 65ff366850aa9956e167e78d4f5b57aae10d8c5779Devang Patel else 66ff366850aa9956e167e78d4f5b57aae10d8c5779Devang Patel SRThreshold = T; 67ff366850aa9956e167e78d4f5b57aae10d8c5779Devang Patel } 68794fd75c67a2cdc128d67342c6d88a504d186896Devang Patel 69ed7b41ea90a17c826f195acbc456c4bb733113d6Chris Lattner bool runOnFunction(Function &F); 70ed7b41ea90a17c826f195acbc456c4bb733113d6Chris Lattner 7138aec325604635380421a27e39ab06d55ed2458dChris Lattner bool performScalarRepl(Function &F); 7238aec325604635380421a27e39ab06d55ed2458dChris Lattner bool performPromotion(Function &F); 7338aec325604635380421a27e39ab06d55ed2458dChris Lattner 74ed7b41ea90a17c826f195acbc456c4bb733113d6Chris Lattner private: 75b1686c32fc694636cbf15a59b23b2a741b65ecf4Cameron Zwarich bool HasDomTree; 7656c3852fb46b7754ad89b998b5968cff0c3937eeChris Lattner TargetData *TD; 776974302e3ff20746268721959efed807c7711bfcBob Wilson 78b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson /// DeadInsts - Keep track of instructions we have made dead, so that 79b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson /// we can remove them after we are done working. 80b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson SmallVector<Value*, 32> DeadInsts; 81b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson 8239a1c04323a5993d6b2993e615ec44c16e19aeeaChris Lattner /// AllocaInfo - When analyzing uses of an alloca instruction, this captures 8339a1c04323a5993d6b2993e615ec44c16e19aeeaChris Lattner /// information about the uses. All these fields are initialized to false 8439a1c04323a5993d6b2993e615ec44c16e19aeeaChris Lattner /// and set to true when something is learned. 8539a1c04323a5993d6b2993e615ec44c16e19aeeaChris Lattner struct AllocaInfo { 866c95d24927b11fb76bc3e76ebe6a8198d74fc178Chris Lattner /// The alloca to promote. 876c95d24927b11fb76bc3e76ebe6a8198d74fc178Chris Lattner AllocaInst *AI; 886c95d24927b11fb76bc3e76ebe6a8198d74fc178Chris Lattner 89145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner /// CheckedPHIs - This is a set of verified PHI nodes, to prevent infinite 90145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner /// looping and avoid redundant work. 91145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner SmallPtrSet<PHINode*, 8> CheckedPHIs; 92145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner 9339a1c04323a5993d6b2993e615ec44c16e19aeeaChris Lattner /// isUnsafe - This is set to true if the alloca cannot be SROA'd. 9439a1c04323a5993d6b2993e615ec44c16e19aeeaChris Lattner bool isUnsafe : 1; 956974302e3ff20746268721959efed807c7711bfcBob Wilson 9639a1c04323a5993d6b2993e615ec44c16e19aeeaChris Lattner /// isMemCpySrc - This is true if this aggregate is memcpy'd from. 9739a1c04323a5993d6b2993e615ec44c16e19aeeaChris Lattner bool isMemCpySrc : 1; 9839a1c04323a5993d6b2993e615ec44c16e19aeeaChris Lattner 9933b0b8d242de8d428f11e77ea734a08b47797216Zhou Sheng /// isMemCpyDst - This is true if this aggregate is memcpy'd into. 10039a1c04323a5993d6b2993e615ec44c16e19aeeaChris Lattner bool isMemCpyDst : 1; 10139a1c04323a5993d6b2993e615ec44c16e19aeeaChris Lattner 1027e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner /// hasSubelementAccess - This is true if a subelement of the alloca is 1037e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner /// ever accessed, or false if the alloca is only accessed with mem 1047e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner /// intrinsics or load/store that only access the entire alloca at once. 1057e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner bool hasSubelementAccess : 1; 1067e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner 1077e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner /// hasALoadOrStore - This is true if there are any loads or stores to it. 1087e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner /// The alloca may just be accessed with memcpy, for example, which would 1097e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner /// not set this. 1107e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner bool hasALoadOrStore : 1; 1117e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner 1126c95d24927b11fb76bc3e76ebe6a8198d74fc178Chris Lattner explicit AllocaInfo(AllocaInst *ai) 1136c95d24927b11fb76bc3e76ebe6a8198d74fc178Chris Lattner : AI(ai), isUnsafe(false), isMemCpySrc(false), isMemCpyDst(false), 1147e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner hasSubelementAccess(false), hasALoadOrStore(false) {} 11539a1c04323a5993d6b2993e615ec44c16e19aeeaChris Lattner }; 1166974302e3ff20746268721959efed807c7711bfcBob Wilson 117ff366850aa9956e167e78d4f5b57aae10d8c5779Devang Patel unsigned SRThreshold; 118ff366850aa9956e167e78d4f5b57aae10d8c5779Devang Patel 119d01a0da090407762fe3b770d84f049d72d06467eChris Lattner void MarkUnsafe(AllocaInfo &I, Instruction *User) { 120d01a0da090407762fe3b770d84f049d72d06467eChris Lattner I.isUnsafe = true; 121d01a0da090407762fe3b770d84f049d72d06467eChris Lattner DEBUG(dbgs() << " Transformation preventing inst: " << *User << '\n'); 122d01a0da090407762fe3b770d84f049d72d06467eChris Lattner } 12339a1c04323a5993d6b2993e615ec44c16e19aeeaChris Lattner 1246c146eefbf75875250af37a0f1ea70fc6b4716eeVictor Hernandez bool isSafeAllocaToScalarRepl(AllocaInst *AI); 12539a1c04323a5993d6b2993e615ec44c16e19aeeaChris Lattner 1266c95d24927b11fb76bc3e76ebe6a8198d74fc178Chris Lattner void isSafeForScalarRepl(Instruction *I, uint64_t Offset, AllocaInfo &Info); 127145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner void isSafePHISelectUseForScalarRepl(Instruction *User, uint64_t Offset, 128145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner AllocaInfo &Info); 1296c95d24927b11fb76bc3e76ebe6a8198d74fc178Chris Lattner void isSafeGEP(GetElementPtrInst *GEPI, uint64_t &Offset, AllocaInfo &Info); 1306c95d24927b11fb76bc3e76ebe6a8198d74fc178Chris Lattner void isSafeMemAccess(uint64_t Offset, uint64_t MemSize, 131d01a0da090407762fe3b770d84f049d72d06467eChris Lattner const Type *MemOpType, bool isStore, AllocaInfo &Info, 132145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner Instruction *TheAccess, bool AllowWholeAccess); 133b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson bool TypeHasComponent(const Type *T, uint64_t Offset, uint64_t Size); 134e88728d757d3090f1c0885b78d3675a7e143a2f9Bob Wilson uint64_t FindElementAndOffset(const Type *&T, uint64_t &Offset, 135e88728d757d3090f1c0885b78d3675a7e143a2f9Bob Wilson const Type *&IdxTy); 1366974302e3ff20746268721959efed807c7711bfcBob Wilson 1376974302e3ff20746268721959efed807c7711bfcBob Wilson void DoScalarReplacement(AllocaInst *AI, 1387b929dad59785f62a66f7c58615082f98441e95eVictor Hernandez std::vector<AllocaInst*> &WorkList); 139b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson void DeleteDeadInstructions(); 1406974302e3ff20746268721959efed807c7711bfcBob Wilson 141b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson void RewriteForScalarRepl(Instruction *I, AllocaInst *AI, uint64_t Offset, 142b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson SmallVector<AllocaInst*, 32> &NewElts); 143b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson void RewriteBitCast(BitCastInst *BC, AllocaInst *AI, uint64_t Offset, 144b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson SmallVector<AllocaInst*, 32> &NewElts); 145b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson void RewriteGEP(GetElementPtrInst *GEPI, AllocaInst *AI, uint64_t Offset, 146b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson SmallVector<AllocaInst*, 32> &NewElts); 147b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson void RewriteMemIntrinUserOfAlloca(MemIntrinsic *MI, Instruction *Inst, 1487b929dad59785f62a66f7c58615082f98441e95eVictor Hernandez AllocaInst *AI, 149d93afec1dbbb1abb3df55e2e007b5f256d09f84aChris Lattner SmallVector<AllocaInst*, 32> &NewElts); 1507b929dad59785f62a66f7c58615082f98441e95eVictor Hernandez void RewriteStoreUserOfWholeAlloca(StoreInst *SI, AllocaInst *AI, 151d2fa781169175b827e50953a1d0b7edc6b0c4801Chris Lattner SmallVector<AllocaInst*, 32> &NewElts); 1527b929dad59785f62a66f7c58615082f98441e95eVictor Hernandez void RewriteLoadUserOfWholeAlloca(LoadInst *LI, AllocaInst *AI, 1536e733d34ca487ab7ff8a6def018a933620393869Chris Lattner SmallVector<AllocaInst*, 32> &NewElts); 1546974302e3ff20746268721959efed807c7711bfcBob Wilson 1559174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky static MemTransferInst *isOnlyCopiedFromConstantGlobal( 1569174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky AllocaInst *AI, SmallVector<Instruction*, 4> &ToDelete); 157ed7b41ea90a17c826f195acbc456c4bb733113d6Chris Lattner }; 158b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner 159b1686c32fc694636cbf15a59b23b2a741b65ecf4Cameron Zwarich // SROA_DT - SROA that uses DominatorTree. 160b1686c32fc694636cbf15a59b23b2a741b65ecf4Cameron Zwarich struct SROA_DT : public SROA { 161b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner static char ID; 162b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner public: 163b1686c32fc694636cbf15a59b23b2a741b65ecf4Cameron Zwarich SROA_DT(int T = -1) : SROA(T, true, ID) { 164b1686c32fc694636cbf15a59b23b2a741b65ecf4Cameron Zwarich initializeSROA_DTPass(*PassRegistry::getPassRegistry()); 165b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner } 166b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner 167b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner // getAnalysisUsage - This pass does not require any passes, but we know it 168b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner // will not alter the CFG, so say so. 169b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner virtual void getAnalysisUsage(AnalysisUsage &AU) const { 170b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner AU.addRequired<DominatorTree>(); 171b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner AU.setPreservesCFG(); 172b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner } 173b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner }; 174b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner 175b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner // SROA_SSAUp - SROA that uses SSAUpdater. 176b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner struct SROA_SSAUp : public SROA { 177b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner static char ID; 178b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner public: 179b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner SROA_SSAUp(int T = -1) : SROA(T, false, ID) { 180b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner initializeSROA_SSAUpPass(*PassRegistry::getPassRegistry()); 181b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner } 182b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner 183b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner // getAnalysisUsage - This pass does not require any passes, but we know it 184b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner // will not alter the CFG, so say so. 185b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner virtual void getAnalysisUsage(AnalysisUsage &AU) const { 186b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner AU.setPreservesCFG(); 187b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner } 188b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner }; 189b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner 190ed7b41ea90a17c826f195acbc456c4bb733113d6Chris Lattner} 191ed7b41ea90a17c826f195acbc456c4bb733113d6Chris Lattner 192b1686c32fc694636cbf15a59b23b2a741b65ecf4Cameron Zwarichchar SROA_DT::ID = 0; 193b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattnerchar SROA_SSAUp::ID = 0; 194b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner 195b1686c32fc694636cbf15a59b23b2a741b65ecf4Cameron ZwarichINITIALIZE_PASS_BEGIN(SROA_DT, "scalarrepl", 196b1686c32fc694636cbf15a59b23b2a741b65ecf4Cameron Zwarich "Scalar Replacement of Aggregates (DT)", false, false) 1972ab36d350293c77fc8941ce1023e4899df7e3a82Owen AndersonINITIALIZE_PASS_DEPENDENCY(DominatorTree) 198b1686c32fc694636cbf15a59b23b2a741b65ecf4Cameron ZwarichINITIALIZE_PASS_END(SROA_DT, "scalarrepl", 199b1686c32fc694636cbf15a59b23b2a741b65ecf4Cameron Zwarich "Scalar Replacement of Aggregates (DT)", false, false) 200b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner 201b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris LattnerINITIALIZE_PASS_BEGIN(SROA_SSAUp, "scalarrepl-ssa", 202b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner "Scalar Replacement of Aggregates (SSAUp)", false, false) 203b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris LattnerINITIALIZE_PASS_END(SROA_SSAUp, "scalarrepl-ssa", 204b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner "Scalar Replacement of Aggregates (SSAUp)", false, false) 205844731a7f1909f55935e3514c9e713a62d67662eDan Gohman 206d0fde30ce850b78371fd1386338350591f9ff494Brian Gaeke// Public interface to the ScalarReplAggregates pass 207b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris LattnerFunctionPass *llvm::createScalarReplAggregatesPass(int Threshold, 208b1686c32fc694636cbf15a59b23b2a741b65ecf4Cameron Zwarich bool UseDomTree) { 209b1686c32fc694636cbf15a59b23b2a741b65ecf4Cameron Zwarich if (UseDomTree) 210b1686c32fc694636cbf15a59b23b2a741b65ecf4Cameron Zwarich return new SROA_DT(Threshold); 211b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner return new SROA_SSAUp(Threshold); 212ff366850aa9956e167e78d4f5b57aae10d8c5779Devang Patel} 213ed7b41ea90a17c826f195acbc456c4bb733113d6Chris Lattner 214ed7b41ea90a17c826f195acbc456c4bb733113d6Chris Lattner 2154cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner//===----------------------------------------------------------------------===// 2164cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner// Convert To Scalar Optimization. 2174cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner//===----------------------------------------------------------------------===// 218963a97f1a365c8d09ca681e922371f9ec3473ee8Chris Lattner 219c4472072641f702dbd99ae12b7da089e75c44a99Chris Lattnernamespace { 220a001b664988f759d194f3d5d880c61449219fc2eChris Lattner/// ConvertToScalarInfo - This class implements the "Convert To Scalar" 221a001b664988f759d194f3d5d880c61449219fc2eChris Lattner/// optimization, which scans the uses of an alloca and determines if it can 222a001b664988f759d194f3d5d880c61449219fc2eChris Lattner/// rewrite it in terms of a single new alloca that can be mem2reg'd. 2234cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattnerclass ConvertToScalarInfo { 224d4c9c3e6b97e095c24d989c0f5ce763f90100ef1Cameron Zwarich /// AllocaSize - The size of the alloca being considered in bytes. 225c4472072641f702dbd99ae12b7da089e75c44a99Chris Lattner unsigned AllocaSize; 226593375d04ab32be0161607a741d310172f142b93Chris Lattner const TargetData &TD; 2276974302e3ff20746268721959efed807c7711bfcBob Wilson 228a0bada729ffaa1bfc80ef25935bdc5a67432708fChris Lattner /// IsNotTrivial - This is set to true if there is some access to the object 229a001b664988f759d194f3d5d880c61449219fc2eChris Lattner /// which means that mem2reg can't promote it. 230c4472072641f702dbd99ae12b7da089e75c44a99Chris Lattner bool IsNotTrivial; 2316974302e3ff20746268721959efed807c7711bfcBob Wilson 232deb74f21f205aa245568ea965132eb076a3bf88cCameron Zwarich /// ScalarKind - Tracks the kind of alloca being considered for promotion, 233deb74f21f205aa245568ea965132eb076a3bf88cCameron Zwarich /// computed based on the uses of the alloca rather than the LLVM type system. 234deb74f21f205aa245568ea965132eb076a3bf88cCameron Zwarich enum { 235deb74f21f205aa245568ea965132eb076a3bf88cCameron Zwarich Unknown, 2365179782cf03cfabfe89df71677e0ffc772b5fdd5Cameron Zwarich 23715cd80c16b4e63b99dcbe45d2baa9456d414aacaCameron Zwarich // Accesses via GEPs that are consistent with element access of a vector 2385179782cf03cfabfe89df71677e0ffc772b5fdd5Cameron Zwarich // type. This will not be converted into a vector unless there is a later 2395179782cf03cfabfe89df71677e0ffc772b5fdd5Cameron Zwarich // access using an actual vector type. 2405179782cf03cfabfe89df71677e0ffc772b5fdd5Cameron Zwarich ImplicitVector, 2415179782cf03cfabfe89df71677e0ffc772b5fdd5Cameron Zwarich 24215cd80c16b4e63b99dcbe45d2baa9456d414aacaCameron Zwarich // Accesses via vector operations and GEPs that are consistent with the 24315cd80c16b4e63b99dcbe45d2baa9456d414aacaCameron Zwarich // layout of a vector type. 244deb74f21f205aa245568ea965132eb076a3bf88cCameron Zwarich Vector, 2455179782cf03cfabfe89df71677e0ffc772b5fdd5Cameron Zwarich 2465179782cf03cfabfe89df71677e0ffc772b5fdd5Cameron Zwarich // An integer bag-of-bits with bitwise operations for insertion and 2475179782cf03cfabfe89df71677e0ffc772b5fdd5Cameron Zwarich // extraction. Any combination of types can be converted into this kind 2485179782cf03cfabfe89df71677e0ffc772b5fdd5Cameron Zwarich // of scalar. 249deb74f21f205aa245568ea965132eb076a3bf88cCameron Zwarich Integer 250deb74f21f205aa245568ea965132eb076a3bf88cCameron Zwarich } ScalarKind; 251deb74f21f205aa245568ea965132eb076a3bf88cCameron Zwarich 252a001b664988f759d194f3d5d880c61449219fc2eChris Lattner /// VectorTy - This tracks the type that we should promote the vector to if 253a001b664988f759d194f3d5d880c61449219fc2eChris Lattner /// it is possible to turn it into a vector. This starts out null, and if it 254a001b664988f759d194f3d5d880c61449219fc2eChris Lattner /// isn't possible to turn into a vector type, it gets set to VoidTy. 255deb74f21f205aa245568ea965132eb076a3bf88cCameron Zwarich const VectorType *VectorTy; 2566974302e3ff20746268721959efed807c7711bfcBob Wilson 2571bcdb6ffad79936a96b46080bf0fed867243b32aCameron Zwarich /// HadNonMemTransferAccess - True if there is at least one access to the 2581bcdb6ffad79936a96b46080bf0fed867243b32aCameron Zwarich /// alloca that is not a MemTransferInst. We don't want to turn structs into 2591bcdb6ffad79936a96b46080bf0fed867243b32aCameron Zwarich /// large integers unless there is some potential for optimization. 26085b0f468cf8390fca3ec356cd498ce0039dbad4fCameron Zwarich bool HadNonMemTransferAccess; 26185b0f468cf8390fca3ec356cd498ce0039dbad4fCameron Zwarich 2624cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattnerpublic: 263593375d04ab32be0161607a741d310172f142b93Chris Lattner explicit ConvertToScalarInfo(unsigned Size, const TargetData &td) 264deb74f21f205aa245568ea965132eb076a3bf88cCameron Zwarich : AllocaSize(Size), TD(td), IsNotTrivial(false), ScalarKind(Unknown), 2655179782cf03cfabfe89df71677e0ffc772b5fdd5Cameron Zwarich VectorTy(0), HadNonMemTransferAccess(false) { } 2666974302e3ff20746268721959efed807c7711bfcBob Wilson 267a001b664988f759d194f3d5d880c61449219fc2eChris Lattner AllocaInst *TryConvert(AllocaInst *AI); 2686974302e3ff20746268721959efed807c7711bfcBob Wilson 2694cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattnerprivate: 270593375d04ab32be0161607a741d310172f142b93Chris Lattner bool CanConvertToScalar(Value *V, uint64_t Offset); 271c0e2607564c1259f2d2c56cbff8f78dc0853860dCameron Zwarich void MergeInTypeForLoadOrStore(const Type *In, uint64_t Offset); 272c9ecd14cee020f884313b60f8696384d3e7848f7Cameron Zwarich bool MergeInVectorType(const VectorType *VInTy, uint64_t Offset); 273593375d04ab32be0161607a741d310172f142b93Chris Lattner void ConvertUsesToScalar(Value *Ptr, AllocaInst *NewAI, uint64_t Offset); 2746974302e3ff20746268721959efed807c7711bfcBob Wilson 275593375d04ab32be0161607a741d310172f142b93Chris Lattner Value *ConvertScalar_ExtractValue(Value *NV, const Type *ToType, 276593375d04ab32be0161607a741d310172f142b93Chris Lattner uint64_t Offset, IRBuilder<> &Builder); 277593375d04ab32be0161607a741d310172f142b93Chris Lattner Value *ConvertScalar_InsertValue(Value *StoredVal, Value *ExistingVal, 278593375d04ab32be0161607a741d310172f142b93Chris Lattner uint64_t Offset, IRBuilder<> &Builder); 279c4472072641f702dbd99ae12b7da089e75c44a99Chris Lattner}; 280c4472072641f702dbd99ae12b7da089e75c44a99Chris Lattner} // end anonymous namespace. 281c4472072641f702dbd99ae12b7da089e75c44a99Chris Lattner 28291abace4ef6fdfe01bcebfb8e90938e71f8a5c4fChris Lattner 283a001b664988f759d194f3d5d880c61449219fc2eChris Lattner/// TryConvert - Analyze the specified alloca, and if it is safe to do so, 284a001b664988f759d194f3d5d880c61449219fc2eChris Lattner/// rewrite it to be a new alloca which is mem2reg'able. This returns the new 285a001b664988f759d194f3d5d880c61449219fc2eChris Lattner/// alloca if possible or null if not. 286a001b664988f759d194f3d5d880c61449219fc2eChris LattnerAllocaInst *ConvertToScalarInfo::TryConvert(AllocaInst *AI) { 287a001b664988f759d194f3d5d880c61449219fc2eChris Lattner // If we can't convert this scalar, or if mem2reg can trivially do it, bail 288a001b664988f759d194f3d5d880c61449219fc2eChris Lattner // out. 289a001b664988f759d194f3d5d880c61449219fc2eChris Lattner if (!CanConvertToScalar(AI, 0) || !IsNotTrivial) 290a001b664988f759d194f3d5d880c61449219fc2eChris Lattner return 0; 2916974302e3ff20746268721959efed807c7711bfcBob Wilson 2925179782cf03cfabfe89df71677e0ffc772b5fdd5Cameron Zwarich // If an alloca has only memset / memcpy uses, it may still have an Unknown 2935179782cf03cfabfe89df71677e0ffc772b5fdd5Cameron Zwarich // ScalarKind. Treat it as an Integer below. 2945179782cf03cfabfe89df71677e0ffc772b5fdd5Cameron Zwarich if (ScalarKind == Unknown) 2955179782cf03cfabfe89df71677e0ffc772b5fdd5Cameron Zwarich ScalarKind = Integer; 2965179782cf03cfabfe89df71677e0ffc772b5fdd5Cameron Zwarich 2973ebb05d9a6bf6604a4b25770cfda1872983b03b2Cameron Zwarich // FIXME: It should be possible to promote the vector type up to the alloca's 2983ebb05d9a6bf6604a4b25770cfda1872983b03b2Cameron Zwarich // size. 2993ebb05d9a6bf6604a4b25770cfda1872983b03b2Cameron Zwarich if (ScalarKind == Vector && VectorTy->getBitWidth() != AllocaSize * 8) 3003ebb05d9a6bf6604a4b25770cfda1872983b03b2Cameron Zwarich ScalarKind = Integer; 3013ebb05d9a6bf6604a4b25770cfda1872983b03b2Cameron Zwarich 302a001b664988f759d194f3d5d880c61449219fc2eChris Lattner // If we were able to find a vector type that can handle this with 303a001b664988f759d194f3d5d880c61449219fc2eChris Lattner // insert/extract elements, and if there was at least one use that had 304a001b664988f759d194f3d5d880c61449219fc2eChris Lattner // a vector type, promote this to a vector. We don't want to promote 305a001b664988f759d194f3d5d880c61449219fc2eChris Lattner // random stuff that doesn't use vectors (e.g. <9 x double>) because then 306a001b664988f759d194f3d5d880c61449219fc2eChris Lattner // we just get a lot of insert/extracts. If at least one vector is 307a001b664988f759d194f3d5d880c61449219fc2eChris Lattner // involved, then we probably really do have a union of vector/array. 308a001b664988f759d194f3d5d880c61449219fc2eChris Lattner const Type *NewTy; 3095b93d3ca6f9c6e81924063abb1487598906dcdabCameron Zwarich if (ScalarKind == Vector) { 3105b93d3ca6f9c6e81924063abb1487598906dcdabCameron Zwarich assert(VectorTy && "Missing type for vector scalar."); 311a001b664988f759d194f3d5d880c61449219fc2eChris Lattner DEBUG(dbgs() << "CONVERT TO VECTOR: " << *AI << "\n TYPE = " 312a001b664988f759d194f3d5d880c61449219fc2eChris Lattner << *VectorTy << '\n'); 313a001b664988f759d194f3d5d880c61449219fc2eChris Lattner NewTy = VectorTy; // Use the vector type. 314a001b664988f759d194f3d5d880c61449219fc2eChris Lattner } else { 31585b0f468cf8390fca3ec356cd498ce0039dbad4fCameron Zwarich unsigned BitWidth = AllocaSize * 8; 3165179782cf03cfabfe89df71677e0ffc772b5fdd5Cameron Zwarich if ((ScalarKind == ImplicitVector || ScalarKind == Integer) && 3175179782cf03cfabfe89df71677e0ffc772b5fdd5Cameron Zwarich !HadNonMemTransferAccess && !TD.fitsInLegalInteger(BitWidth)) 31885b0f468cf8390fca3ec356cd498ce0039dbad4fCameron Zwarich return 0; 31985b0f468cf8390fca3ec356cd498ce0039dbad4fCameron Zwarich 320a001b664988f759d194f3d5d880c61449219fc2eChris Lattner DEBUG(dbgs() << "CONVERT TO SCALAR INTEGER: " << *AI << "\n"); 321a001b664988f759d194f3d5d880c61449219fc2eChris Lattner // Create and insert the integer alloca. 32285b0f468cf8390fca3ec356cd498ce0039dbad4fCameron Zwarich NewTy = IntegerType::get(AI->getContext(), BitWidth); 323a001b664988f759d194f3d5d880c61449219fc2eChris Lattner } 324a001b664988f759d194f3d5d880c61449219fc2eChris Lattner AllocaInst *NewAI = new AllocaInst(NewTy, 0, "", AI->getParent()->begin()); 325a001b664988f759d194f3d5d880c61449219fc2eChris Lattner ConvertUsesToScalar(AI, NewAI, 0); 326a001b664988f759d194f3d5d880c61449219fc2eChris Lattner return NewAI; 327a001b664988f759d194f3d5d880c61449219fc2eChris Lattner} 328a001b664988f759d194f3d5d880c61449219fc2eChris Lattner 329c0e2607564c1259f2d2c56cbff8f78dc0853860dCameron Zwarich/// MergeInTypeForLoadOrStore - Add the 'In' type to the accumulated vector type 330c0e2607564c1259f2d2c56cbff8f78dc0853860dCameron Zwarich/// (VectorTy) so far at the offset specified by Offset (which is specified in 331c0e2607564c1259f2d2c56cbff8f78dc0853860dCameron Zwarich/// bytes). 3324cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// 333b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich/// There are three cases we handle here: 3344cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// 1) A union of vector types of the same size and potentially its elements. 3354cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// Here we turn element accesses into insert/extract element operations. 3364cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// This promotes a <4 x float> with a store of float to the third element 3374cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// into a <4 x float> that uses insert element. 338b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich/// 2) A union of vector types with power-of-2 size differences, e.g. a float, 339b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich/// <2 x float> and <4 x float>. Here we turn element accesses into insert 340b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich/// and extract element operations, and <2 x float> accesses into a cast to 341b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich/// <2 x double>, an extract, and a cast back to <2 x float>. 342b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich/// 3) A fully general blob of memory, which we turn into some (potentially 3434cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// large) integer type with extract and insert operations where the loads 344a001b664988f759d194f3d5d880c61449219fc2eChris Lattner/// and stores would mutate the memory. We mark this by setting VectorTy 345a001b664988f759d194f3d5d880c61449219fc2eChris Lattner/// to VoidTy. 346c0e2607564c1259f2d2c56cbff8f78dc0853860dCameron Zwarichvoid ConvertToScalarInfo::MergeInTypeForLoadOrStore(const Type *In, 347c0e2607564c1259f2d2c56cbff8f78dc0853860dCameron Zwarich uint64_t Offset) { 348a001b664988f759d194f3d5d880c61449219fc2eChris Lattner // If we already decided to turn this into a blob of integer memory, there is 349a001b664988f759d194f3d5d880c61449219fc2eChris Lattner // nothing to be done. 350deb74f21f205aa245568ea965132eb076a3bf88cCameron Zwarich if (ScalarKind == Integer) 3514cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return; 3526974302e3ff20746268721959efed807c7711bfcBob Wilson 3534cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If this could be contributing to a vector, analyze it. 354c4472072641f702dbd99ae12b7da089e75c44a99Chris Lattner 3554cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If the In type is a vector that is the same size as the alloca, see if it 3564cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // matches the existing VecTy. 3574cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (const VectorType *VInTy = dyn_cast<VectorType>(In)) { 358c9ecd14cee020f884313b60f8696384d3e7848f7Cameron Zwarich if (MergeInVectorType(VInTy, Offset)) 3594cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return; 3604cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } else if (In->isFloatTy() || In->isDoubleTy() || 3614cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner (In->isIntegerTy() && In->getPrimitiveSizeInBits() >= 8 && 3624cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner isPowerOf2_32(In->getPrimitiveSizeInBits()))) { 3639827b78b51f285e90c2b1e5add9b28d10c88595cCameron Zwarich // Full width accesses can be ignored, because they can always be turned 3649827b78b51f285e90c2b1e5add9b28d10c88595cCameron Zwarich // into bitcasts. 3659827b78b51f285e90c2b1e5add9b28d10c88595cCameron Zwarich unsigned EltSize = In->getPrimitiveSizeInBits()/8; 366dd68912801861273dc3dca33cfc18357213049a4Cameron Zwarich if (EltSize == AllocaSize) 3679827b78b51f285e90c2b1e5add9b28d10c88595cCameron Zwarich return; 3685fc1282c1822d692ed1681cdc4c315950c6eb1d8Cameron Zwarich 3694cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If we're accessing something that could be an element of a vector, see 3704cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // if the implied vector agrees with what we already have and if Offset is 3714cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // compatible with it. 37296cc1d0dfbcf9c7ffffc65f0aa008ff532d444f4Cameron Zwarich if (Offset % EltSize == 0 && AllocaSize % EltSize == 0 && 373c4f78208b399111cc4f5d97ed1875566819f34b4Cameron Zwarich (!VectorTy || Offset * 8 < VectorTy->getPrimitiveSizeInBits())) { 3745fc1282c1822d692ed1681cdc4c315950c6eb1d8Cameron Zwarich if (!VectorTy) { 3755179782cf03cfabfe89df71677e0ffc772b5fdd5Cameron Zwarich ScalarKind = ImplicitVector; 3764cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner VectorTy = VectorType::get(In, AllocaSize/EltSize); 3775fc1282c1822d692ed1681cdc4c315950c6eb1d8Cameron Zwarich return; 3785fc1282c1822d692ed1681cdc4c315950c6eb1d8Cameron Zwarich } 3795fc1282c1822d692ed1681cdc4c315950c6eb1d8Cameron Zwarich 380deb74f21f205aa245568ea965132eb076a3bf88cCameron Zwarich unsigned CurrentEltSize = VectorTy->getElementType() 3815fc1282c1822d692ed1681cdc4c315950c6eb1d8Cameron Zwarich ->getPrimitiveSizeInBits()/8; 3825fc1282c1822d692ed1681cdc4c315950c6eb1d8Cameron Zwarich if (EltSize == CurrentEltSize) 3835fc1282c1822d692ed1681cdc4c315950c6eb1d8Cameron Zwarich return; 384344731c01805aeda49c747bac6148501fa85557cCameron Zwarich 385344731c01805aeda49c747bac6148501fa85557cCameron Zwarich if (In->isIntegerTy() && isPowerOf2_32(AllocaSize / EltSize)) 386344731c01805aeda49c747bac6148501fa85557cCameron Zwarich return; 3874cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 3884cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 3896974302e3ff20746268721959efed807c7711bfcBob Wilson 3904cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Otherwise, we have a case that we can't handle with an optimized vector 3914cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // form. We can still turn this into a large integer. 392deb74f21f205aa245568ea965132eb076a3bf88cCameron Zwarich ScalarKind = Integer; 3934cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner} 394c4472072641f702dbd99ae12b7da089e75c44a99Chris Lattner 395c0e2607564c1259f2d2c56cbff8f78dc0853860dCameron Zwarich/// MergeInVectorType - Handles the vector case of MergeInTypeForLoadOrStore, 396c0e2607564c1259f2d2c56cbff8f78dc0853860dCameron Zwarich/// returning true if the type was successfully merged and false otherwise. 397c9ecd14cee020f884313b60f8696384d3e7848f7Cameron Zwarichbool ConvertToScalarInfo::MergeInVectorType(const VectorType *VInTy, 398c9ecd14cee020f884313b60f8696384d3e7848f7Cameron Zwarich uint64_t Offset) { 399b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich // TODO: Support nonzero offsets? 400b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich if (Offset != 0) 401b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich return false; 402b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich 403b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich // Only allow vectors that are a power-of-2 away from the size of the alloca. 404b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich if (!isPowerOf2_64(AllocaSize / (VInTy->getBitWidth() / 8))) 405b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich return false; 406b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich 407b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich // If this the first vector we see, remember the type so that we know the 408b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich // element size. 409b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich if (!VectorTy) { 410deb74f21f205aa245568ea965132eb076a3bf88cCameron Zwarich ScalarKind = Vector; 411b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich VectorTy = VInTy; 412c9ecd14cee020f884313b60f8696384d3e7848f7Cameron Zwarich return true; 413c9ecd14cee020f884313b60f8696384d3e7848f7Cameron Zwarich } 414c9ecd14cee020f884313b60f8696384d3e7848f7Cameron Zwarich 415deb74f21f205aa245568ea965132eb076a3bf88cCameron Zwarich unsigned BitWidth = VectorTy->getBitWidth(); 416b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich unsigned InBitWidth = VInTy->getBitWidth(); 417b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich 418b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich // Vectors of the same size can be converted using a simple bitcast. 4195179782cf03cfabfe89df71677e0ffc772b5fdd5Cameron Zwarich if (InBitWidth == BitWidth && AllocaSize == (InBitWidth / 8)) { 4205179782cf03cfabfe89df71677e0ffc772b5fdd5Cameron Zwarich ScalarKind = Vector; 421b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich return true; 4225179782cf03cfabfe89df71677e0ffc772b5fdd5Cameron Zwarich } 423b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich 424deb74f21f205aa245568ea965132eb076a3bf88cCameron Zwarich const Type *ElementTy = VectorTy->getElementType(); 425deb74f21f205aa245568ea965132eb076a3bf88cCameron Zwarich const Type *InElementTy = VInTy->getElementType(); 426b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich 427b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich // Do not allow mixed integer and floating-point accesses from vectors of 428b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich // different sizes. 429b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich if (ElementTy->isFloatingPointTy() != InElementTy->isFloatingPointTy()) 430b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich return false; 431b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich 432b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich if (ElementTy->isFloatingPointTy()) { 433b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich // Only allow floating-point vectors of different sizes if they have the 434b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich // same element type. 435b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich // TODO: This could be loosened a bit, but would anything benefit? 436b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich if (ElementTy != InElementTy) 437b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich return false; 438b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich 439b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich // There are no arbitrary-precision floating-point types, which limits the 440b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich // number of legal vector types with larger element types that we can form 441b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich // to bitcast and extract a subvector. 442b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich // TODO: We could support some more cases with mixed fp128 and double here. 443b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich if (!(BitWidth == 64 || BitWidth == 128) || 444b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich !(InBitWidth == 64 || InBitWidth == 128)) 445b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich return false; 446b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich } else { 447b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich assert(ElementTy->isIntegerTy() && "Vector elements must be either integer " 448b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich "or floating-point."); 449b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich unsigned BitWidth = ElementTy->getPrimitiveSizeInBits(); 450b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich unsigned InBitWidth = InElementTy->getPrimitiveSizeInBits(); 451b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich 452b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich // Do not allow integer types smaller than a byte or types whose widths are 453b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich // not a multiple of a byte. 454b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich if (BitWidth < 8 || InBitWidth < 8 || 455b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich BitWidth % 8 != 0 || InBitWidth % 8 != 0) 456b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich return false; 457b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich } 458b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich 459b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich // Pick the largest of the two vector types. 4605179782cf03cfabfe89df71677e0ffc772b5fdd5Cameron Zwarich ScalarKind = Vector; 461b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich if (InBitWidth > BitWidth) 462b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich VectorTy = VInTy; 463b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich 464b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich return true; 465c9ecd14cee020f884313b60f8696384d3e7848f7Cameron Zwarich} 466c9ecd14cee020f884313b60f8696384d3e7848f7Cameron Zwarich 4674cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// CanConvertToScalar - V is a pointer. If we can convert the pointee and all 4684cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// its accesses to a single vector type, return true and set VecTy to 4694cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// the new type. If we could convert the alloca into a single promotable 4704cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// integer, return true but set VecTy to VoidTy. Further, if the use is not a 4714cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// completely trivial use that mem2reg could promote, set IsNotTrivial. Offset 4724cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// is the current offset from the base of the alloca being analyzed. 4734cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// 4744cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// If we see at least one access to the value that is as a vector type, set the 4754cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// SawVec flag. 4764cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattnerbool ConvertToScalarInfo::CanConvertToScalar(Value *V, uint64_t Offset) { 4774cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner for (Value::use_iterator UI = V->use_begin(), E = V->use_end(); UI!=E; ++UI) { 4784cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Instruction *User = cast<Instruction>(*UI); 4796974302e3ff20746268721959efed807c7711bfcBob Wilson 4804cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (LoadInst *LI = dyn_cast<LoadInst>(User)) { 4814cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Don't break volatile loads. 4824cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (LI->isVolatile()) 4834cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return false; 4840488fb649a56b7fc89a5814df5308813f9e5a85dDale Johannesen // Don't touch MMX operations. 4850488fb649a56b7fc89a5814df5308813f9e5a85dDale Johannesen if (LI->getType()->isX86_MMXTy()) 4860488fb649a56b7fc89a5814df5308813f9e5a85dDale Johannesen return false; 48785b0f468cf8390fca3ec356cd498ce0039dbad4fCameron Zwarich HadNonMemTransferAccess = true; 488c0e2607564c1259f2d2c56cbff8f78dc0853860dCameron Zwarich MergeInTypeForLoadOrStore(LI->getType(), Offset); 489add2bd7f5941537a97a41e037ae2277fbeed0b4fChris Lattner continue; 490add2bd7f5941537a97a41e037ae2277fbeed0b4fChris Lattner } 4916974302e3ff20746268721959efed807c7711bfcBob Wilson 4924cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (StoreInst *SI = dyn_cast<StoreInst>(User)) { 4934cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Storing the pointer, not into the value? 4944cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (SI->getOperand(0) == V || SI->isVolatile()) return false; 4950488fb649a56b7fc89a5814df5308813f9e5a85dDale Johannesen // Don't touch MMX operations. 4960488fb649a56b7fc89a5814df5308813f9e5a85dDale Johannesen if (SI->getOperand(0)->getType()->isX86_MMXTy()) 4970488fb649a56b7fc89a5814df5308813f9e5a85dDale Johannesen return false; 49885b0f468cf8390fca3ec356cd498ce0039dbad4fCameron Zwarich HadNonMemTransferAccess = true; 499c0e2607564c1259f2d2c56cbff8f78dc0853860dCameron Zwarich MergeInTypeForLoadOrStore(SI->getOperand(0)->getType(), Offset); 5007809ecd5b019d26498499121f4d9c0b7de2f0a14Chris Lattner continue; 5017809ecd5b019d26498499121f4d9c0b7de2f0a14Chris Lattner } 5026974302e3ff20746268721959efed807c7711bfcBob Wilson 5034cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (BitCastInst *BCI = dyn_cast<BitCastInst>(User)) { 504a001b664988f759d194f3d5d880c61449219fc2eChris Lattner IsNotTrivial = true; // Can't be mem2reg'd. 5054cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (!CanConvertToScalar(BCI, Offset)) 5064cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return false; 5073992feb075b27ff37b63017078a977206f97d10dBob Wilson continue; 5083992feb075b27ff37b63017078a977206f97d10dBob Wilson } 5093992feb075b27ff37b63017078a977206f97d10dBob Wilson 5104cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(User)) { 5114cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If this is a GEP with a variable indices, we can't handle it. 5124cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (!GEP->hasAllConstantIndices()) 5134cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return false; 5146974302e3ff20746268721959efed807c7711bfcBob Wilson 5154cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Compute the offset that this GEP adds to the pointer. 5164cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner SmallVector<Value*, 8> Indices(GEP->op_begin()+1, GEP->op_end()); 5174cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t GEPOffset = TD.getIndexedOffset(GEP->getPointerOperandType(), 5184cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner &Indices[0], Indices.size()); 5194cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // See if all uses can be converted. 5204cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (!CanConvertToScalar(GEP, Offset+GEPOffset)) 5214cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return false; 522a001b664988f759d194f3d5d880c61449219fc2eChris Lattner IsNotTrivial = true; // Can't be mem2reg'd. 52385b0f468cf8390fca3ec356cd498ce0039dbad4fCameron Zwarich HadNonMemTransferAccess = true; 5247809ecd5b019d26498499121f4d9c0b7de2f0a14Chris Lattner continue; 5254cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 526ed7b41ea90a17c826f195acbc456c4bb733113d6Chris Lattner 5274cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If this is a constant sized memset of a constant value (e.g. 0) we can 5284cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // handle it. 5294cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (MemSetInst *MSI = dyn_cast<MemSetInst>(User)) { 5306be41eb7f00319f5ffa1a5435dcd1e81b3ce932dCameron Zwarich // Store of constant value. 5316be41eb7f00319f5ffa1a5435dcd1e81b3ce932dCameron Zwarich if (!isa<ConstantInt>(MSI->getValue())) 532a001b664988f759d194f3d5d880c61449219fc2eChris Lattner return false; 5336be41eb7f00319f5ffa1a5435dcd1e81b3ce932dCameron Zwarich 5346be41eb7f00319f5ffa1a5435dcd1e81b3ce932dCameron Zwarich // Store of constant size. 5356be41eb7f00319f5ffa1a5435dcd1e81b3ce932dCameron Zwarich ConstantInt *Len = dyn_cast<ConstantInt>(MSI->getLength()); 5366be41eb7f00319f5ffa1a5435dcd1e81b3ce932dCameron Zwarich if (!Len) 5376be41eb7f00319f5ffa1a5435dcd1e81b3ce932dCameron Zwarich return false; 5386be41eb7f00319f5ffa1a5435dcd1e81b3ce932dCameron Zwarich 5396be41eb7f00319f5ffa1a5435dcd1e81b3ce932dCameron Zwarich // If the size differs from the alloca, we can only convert the alloca to 5406be41eb7f00319f5ffa1a5435dcd1e81b3ce932dCameron Zwarich // an integer bag-of-bits. 5416be41eb7f00319f5ffa1a5435dcd1e81b3ce932dCameron Zwarich // FIXME: This should handle all of the cases that are currently accepted 5426be41eb7f00319f5ffa1a5435dcd1e81b3ce932dCameron Zwarich // as vector element insertions. 5436be41eb7f00319f5ffa1a5435dcd1e81b3ce932dCameron Zwarich if (Len->getZExtValue() != AllocaSize || Offset != 0) 5446be41eb7f00319f5ffa1a5435dcd1e81b3ce932dCameron Zwarich ScalarKind = Integer; 5456be41eb7f00319f5ffa1a5435dcd1e81b3ce932dCameron Zwarich 546a001b664988f759d194f3d5d880c61449219fc2eChris Lattner IsNotTrivial = true; // Can't be mem2reg'd. 54785b0f468cf8390fca3ec356cd498ce0039dbad4fCameron Zwarich HadNonMemTransferAccess = true; 548a001b664988f759d194f3d5d880c61449219fc2eChris Lattner continue; 5494cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 550fd93908ae8b9684fe71c239e3c6cfe13ff6a2663Misha Brukman 5514cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If this is a memcpy or memmove into or out of the whole allocation, we 5524cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // can handle it like a load or store of the scalar type. 5534cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (MemTransferInst *MTI = dyn_cast<MemTransferInst>(User)) { 554a001b664988f759d194f3d5d880c61449219fc2eChris Lattner ConstantInt *Len = dyn_cast<ConstantInt>(MTI->getLength()); 555a001b664988f759d194f3d5d880c61449219fc2eChris Lattner if (Len == 0 || Len->getZExtValue() != AllocaSize || Offset != 0) 556a001b664988f759d194f3d5d880c61449219fc2eChris Lattner return false; 5576974302e3ff20746268721959efed807c7711bfcBob Wilson 558a001b664988f759d194f3d5d880c61449219fc2eChris Lattner IsNotTrivial = true; // Can't be mem2reg'd. 559a001b664988f759d194f3d5d880c61449219fc2eChris Lattner continue; 560ed7b41ea90a17c826f195acbc456c4bb733113d6Chris Lattner } 5616974302e3ff20746268721959efed807c7711bfcBob Wilson 5624cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Otherwise, we cannot handle this! 5634cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return false; 564a10b29b84b63c448b7cb423598d3a38b0f55cddbChris Lattner } 5656974302e3ff20746268721959efed807c7711bfcBob Wilson 5664cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return true; 567ed7b41ea90a17c826f195acbc456c4bb733113d6Chris Lattner} 568a59adc40153f3e0f9843952c127d179b5ebe6c4cChris Lattner 5694cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// ConvertUsesToScalar - Convert all of the users of Ptr to use the new alloca 5704cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// directly. This happens when we are converting an "integer union" to a 5714cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// single integer scalar, or when we are converting a "vector union" to a 5724cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// vector with insert/extractelement instructions. 5734cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// 5744cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// Offset is an offset from the original alloca, in bits that need to be 5754cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// shifted to the right. By the end of this, there should be no uses of Ptr. 5764cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattnervoid ConvertToScalarInfo::ConvertUsesToScalar(Value *Ptr, AllocaInst *NewAI, 5774cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t Offset) { 5784cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner while (!Ptr->use_empty()) { 5794cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Instruction *User = cast<Instruction>(Ptr->use_back()); 580b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson 5814cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (BitCastInst *CI = dyn_cast<BitCastInst>(User)) { 5824cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner ConvertUsesToScalar(CI, NewAI, Offset); 5834cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner CI->eraseFromParent(); 5844cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner continue; 5854cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 586b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson 5874cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(User)) { 5884cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Compute the offset that this GEP adds to the pointer. 5894cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner SmallVector<Value*, 8> Indices(GEP->op_begin()+1, GEP->op_end()); 5904cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t GEPOffset = TD.getIndexedOffset(GEP->getPointerOperandType(), 5914cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner &Indices[0], Indices.size()); 5924cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner ConvertUsesToScalar(GEP, NewAI, Offset+GEPOffset*8); 5934cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner GEP->eraseFromParent(); 5944cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner continue; 5954cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 5966974302e3ff20746268721959efed807c7711bfcBob Wilson 59761db1f56d0b717d67557bbb2a9d83af1449458cbChris Lattner IRBuilder<> Builder(User); 5986974302e3ff20746268721959efed807c7711bfcBob Wilson 5994cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (LoadInst *LI = dyn_cast<LoadInst>(User)) { 6004cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // The load is a bit extract from NewAI shifted right by Offset bits. 6014cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *LoadedVal = Builder.CreateLoad(NewAI, "tmp"); 6024cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *NewLoadVal 6034cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner = ConvertScalar_ExtractValue(LoadedVal, LI->getType(), Offset, Builder); 6044cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner LI->replaceAllUsesWith(NewLoadVal); 6054cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner LI->eraseFromParent(); 6064cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner continue; 6074cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 6086974302e3ff20746268721959efed807c7711bfcBob Wilson 6094cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (StoreInst *SI = dyn_cast<StoreInst>(User)) { 6104cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner assert(SI->getOperand(0) != Ptr && "Consistency error!"); 6114cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Instruction *Old = Builder.CreateLoad(NewAI, NewAI->getName()+".in"); 6124cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *New = ConvertScalar_InsertValue(SI->getOperand(0), Old, Offset, 6134cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Builder); 6144cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Builder.CreateStore(New, NewAI); 6154cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner SI->eraseFromParent(); 6166974302e3ff20746268721959efed807c7711bfcBob Wilson 6174cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If the load we just inserted is now dead, then the inserted store 6184cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // overwrote the entire thing. 6194cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (Old->use_empty()) 6204cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Old->eraseFromParent(); 6214cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner continue; 6224cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 6236974302e3ff20746268721959efed807c7711bfcBob Wilson 6244cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If this is a constant sized memset of a constant value (e.g. 0) we can 6254cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // transform it into a store of the expanded constant value. 6264cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (MemSetInst *MSI = dyn_cast<MemSetInst>(User)) { 6274cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner assert(MSI->getRawDest() == Ptr && "Consistency error!"); 6284cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner unsigned NumBytes = cast<ConstantInt>(MSI->getLength())->getZExtValue(); 6294cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (NumBytes != 0) { 6304cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner unsigned Val = cast<ConstantInt>(MSI->getValue())->getZExtValue(); 6316974302e3ff20746268721959efed807c7711bfcBob Wilson 6324cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Compute the value replicated the right number of times. 6334cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner APInt APVal(NumBytes*8, Val); 6342674089cefe519195e00bdf879647438cfb1cb0fDaniel Dunbar 6354cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Splat the value if non-zero. 6364cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (Val) 6374cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner for (unsigned i = 1; i != NumBytes; ++i) 6384cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner APVal |= APVal << 8; 6396974302e3ff20746268721959efed807c7711bfcBob Wilson 6404cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Instruction *Old = Builder.CreateLoad(NewAI, NewAI->getName()+".in"); 6414cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *New = ConvertScalar_InsertValue( 6424cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner ConstantInt::get(User->getContext(), APVal), 6434cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Old, Offset, Builder); 6444cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Builder.CreateStore(New, NewAI); 6456974302e3ff20746268721959efed807c7711bfcBob Wilson 6464cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If the load we just inserted is now dead, then the memset overwrote 6474cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // the entire thing. 6484cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (Old->use_empty()) 6496974302e3ff20746268721959efed807c7711bfcBob Wilson Old->eraseFromParent(); 6504cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 6514cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner MSI->eraseFromParent(); 6524cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner continue; 653b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson } 654fca55c8ac7d12e4139ad0ab7d74b76c47935aef6Daniel Dunbar 6554cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If this is a memcpy or memmove into or out of the whole allocation, we 6564cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // can handle it like a load or store of the scalar type. 6574cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (MemTransferInst *MTI = dyn_cast<MemTransferInst>(User)) { 6584cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner assert(Offset == 0 && "must be store to start of alloca"); 6596974302e3ff20746268721959efed807c7711bfcBob Wilson 6604cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If the source and destination are both to the same alloca, then this is 6614cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // a noop copy-to-self, just delete it. Otherwise, emit a load and store 6624cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // as appropriate. 663bd1801b5553c8be3960255a92738464e0010b6f6Dan Gohman AllocaInst *OrigAI = cast<AllocaInst>(GetUnderlyingObject(Ptr, &TD, 0)); 6646974302e3ff20746268721959efed807c7711bfcBob Wilson 665bd1801b5553c8be3960255a92738464e0010b6f6Dan Gohman if (GetUnderlyingObject(MTI->getSource(), &TD, 0) != OrigAI) { 6664cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Dest must be OrigAI, change this to be a load from the original 6674cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // pointer (bitcasted), then a store to our new alloca. 6684cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner assert(MTI->getRawDest() == Ptr && "Neither use is of pointer?"); 6694cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *SrcPtr = MTI->getSource(); 670e90a6333c3a4514f88c8a3dddd10d9bcddcd6d85Mon P Wang const PointerType* SPTy = cast<PointerType>(SrcPtr->getType()); 671e90a6333c3a4514f88c8a3dddd10d9bcddcd6d85Mon P Wang const PointerType* AIPTy = cast<PointerType>(NewAI->getType()); 672e90a6333c3a4514f88c8a3dddd10d9bcddcd6d85Mon P Wang if (SPTy->getAddressSpace() != AIPTy->getAddressSpace()) { 673e90a6333c3a4514f88c8a3dddd10d9bcddcd6d85Mon P Wang AIPTy = PointerType::get(AIPTy->getElementType(), 674e90a6333c3a4514f88c8a3dddd10d9bcddcd6d85Mon P Wang SPTy->getAddressSpace()); 675e90a6333c3a4514f88c8a3dddd10d9bcddcd6d85Mon P Wang } 676e90a6333c3a4514f88c8a3dddd10d9bcddcd6d85Mon P Wang SrcPtr = Builder.CreateBitCast(SrcPtr, AIPTy); 677e90a6333c3a4514f88c8a3dddd10d9bcddcd6d85Mon P Wang 6784cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner LoadInst *SrcVal = Builder.CreateLoad(SrcPtr, "srcval"); 6794cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner SrcVal->setAlignment(MTI->getAlignment()); 6804cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Builder.CreateStore(SrcVal, NewAI); 681bd1801b5553c8be3960255a92738464e0010b6f6Dan Gohman } else if (GetUnderlyingObject(MTI->getDest(), &TD, 0) != OrigAI) { 6824cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Src must be OrigAI, change this to be a load from NewAI then a store 6834cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // through the original dest pointer (bitcasted). 6844cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner assert(MTI->getRawSource() == Ptr && "Neither use is of pointer?"); 6854cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner LoadInst *SrcVal = Builder.CreateLoad(NewAI, "srcval"); 686b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson 687e90a6333c3a4514f88c8a3dddd10d9bcddcd6d85Mon P Wang const PointerType* DPTy = cast<PointerType>(MTI->getDest()->getType()); 688e90a6333c3a4514f88c8a3dddd10d9bcddcd6d85Mon P Wang const PointerType* AIPTy = cast<PointerType>(NewAI->getType()); 689e90a6333c3a4514f88c8a3dddd10d9bcddcd6d85Mon P Wang if (DPTy->getAddressSpace() != AIPTy->getAddressSpace()) { 690e90a6333c3a4514f88c8a3dddd10d9bcddcd6d85Mon P Wang AIPTy = PointerType::get(AIPTy->getElementType(), 691e90a6333c3a4514f88c8a3dddd10d9bcddcd6d85Mon P Wang DPTy->getAddressSpace()); 692e90a6333c3a4514f88c8a3dddd10d9bcddcd6d85Mon P Wang } 693e90a6333c3a4514f88c8a3dddd10d9bcddcd6d85Mon P Wang Value *DstPtr = Builder.CreateBitCast(MTI->getDest(), AIPTy); 694e90a6333c3a4514f88c8a3dddd10d9bcddcd6d85Mon P Wang 6954cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner StoreInst *NewStore = Builder.CreateStore(SrcVal, DstPtr); 6964cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner NewStore->setAlignment(MTI->getAlignment()); 6974cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } else { 6984cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Noop transfer. Src == Dst 6994cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 7005fac55fafb53fde5c548bcd08e07418e9d8e549fMatthijs Kooijman 7014cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner MTI->eraseFromParent(); 7024cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner continue; 7034cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 7046974302e3ff20746268721959efed807c7711bfcBob Wilson 7054cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner llvm_unreachable("Unsupported operation!"); 70688e6dc8bf14e8a98888f62173a6581386b8d29a0Chris Lattner } 7072674089cefe519195e00bdf879647438cfb1cb0fDaniel Dunbar} 7082674089cefe519195e00bdf879647438cfb1cb0fDaniel Dunbar 709b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich/// getScaledElementType - Gets a scaled element type for a partial vector 710344731c01805aeda49c747bac6148501fa85557cCameron Zwarich/// access of an alloca. The input types must be integer or floating-point 711344731c01805aeda49c747bac6148501fa85557cCameron Zwarich/// scalar or vector types, and the resulting type is an integer, float or 712344731c01805aeda49c747bac6148501fa85557cCameron Zwarich/// double. 713344731c01805aeda49c747bac6148501fa85557cCameron Zwarichstatic const Type *getScaledElementType(const Type *Ty1, const Type *Ty2, 7141537ce75ed25bbca58096383bb1fb9dd427bf1aaCameron Zwarich unsigned NewBitWidth) { 715344731c01805aeda49c747bac6148501fa85557cCameron Zwarich bool IsFP1 = Ty1->isFloatingPointTy() || 716344731c01805aeda49c747bac6148501fa85557cCameron Zwarich (Ty1->isVectorTy() && 717344731c01805aeda49c747bac6148501fa85557cCameron Zwarich cast<VectorType>(Ty1)->getElementType()->isFloatingPointTy()); 718344731c01805aeda49c747bac6148501fa85557cCameron Zwarich bool IsFP2 = Ty2->isFloatingPointTy() || 719344731c01805aeda49c747bac6148501fa85557cCameron Zwarich (Ty2->isVectorTy() && 720344731c01805aeda49c747bac6148501fa85557cCameron Zwarich cast<VectorType>(Ty2)->getElementType()->isFloatingPointTy()); 721344731c01805aeda49c747bac6148501fa85557cCameron Zwarich 722344731c01805aeda49c747bac6148501fa85557cCameron Zwarich LLVMContext &Context = Ty1->getContext(); 723344731c01805aeda49c747bac6148501fa85557cCameron Zwarich 724344731c01805aeda49c747bac6148501fa85557cCameron Zwarich // Prefer floating-point types over integer types, as integer types may have 725344731c01805aeda49c747bac6148501fa85557cCameron Zwarich // been created by earlier scalar replacement. 726344731c01805aeda49c747bac6148501fa85557cCameron Zwarich if (IsFP1 || IsFP2) { 727344731c01805aeda49c747bac6148501fa85557cCameron Zwarich if (NewBitWidth == 32) 728344731c01805aeda49c747bac6148501fa85557cCameron Zwarich return Type::getFloatTy(Context); 729344731c01805aeda49c747bac6148501fa85557cCameron Zwarich if (NewBitWidth == 64) 730344731c01805aeda49c747bac6148501fa85557cCameron Zwarich return Type::getDoubleTy(Context); 731344731c01805aeda49c747bac6148501fa85557cCameron Zwarich } 732b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich 733344731c01805aeda49c747bac6148501fa85557cCameron Zwarich return Type::getIntNTy(Context, NewBitWidth); 734b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich} 735b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich 736ddf9abf2b6ee3a1104057df20ec3be61b410441eMon P Wang/// CreateShuffleVectorCast - Creates a shuffle vector to convert one vector 737ddf9abf2b6ee3a1104057df20ec3be61b410441eMon P Wang/// to another vector of the same element type which has the same allocation 738ddf9abf2b6ee3a1104057df20ec3be61b410441eMon P Wang/// size but different primitive sizes (e.g. <3 x i32> and <4 x i32>). 739ddf9abf2b6ee3a1104057df20ec3be61b410441eMon P Wangstatic Value *CreateShuffleVectorCast(Value *FromVal, const Type *ToType, 740ddf9abf2b6ee3a1104057df20ec3be61b410441eMon P Wang IRBuilder<> &Builder) { 741ddf9abf2b6ee3a1104057df20ec3be61b410441eMon P Wang const Type *FromType = FromVal->getType(); 742481823aa819ea1dd25567ae616dca93056ef770aMon P Wang const VectorType *FromVTy = cast<VectorType>(FromType); 743481823aa819ea1dd25567ae616dca93056ef770aMon P Wang const VectorType *ToVTy = cast<VectorType>(ToType); 744481823aa819ea1dd25567ae616dca93056ef770aMon P Wang assert((ToVTy->getElementType() == FromVTy->getElementType()) && 745ddf9abf2b6ee3a1104057df20ec3be61b410441eMon P Wang "Vectors must have the same element type"); 746ddf9abf2b6ee3a1104057df20ec3be61b410441eMon P Wang Value *UnV = UndefValue::get(FromType); 747ddf9abf2b6ee3a1104057df20ec3be61b410441eMon P Wang unsigned numEltsFrom = FromVTy->getNumElements(); 748ddf9abf2b6ee3a1104057df20ec3be61b410441eMon P Wang unsigned numEltsTo = ToVTy->getNumElements(); 749ddf9abf2b6ee3a1104057df20ec3be61b410441eMon P Wang 750ddf9abf2b6ee3a1104057df20ec3be61b410441eMon P Wang SmallVector<Constant*, 3> Args; 751481823aa819ea1dd25567ae616dca93056ef770aMon P Wang const Type* Int32Ty = Builder.getInt32Ty(); 752ddf9abf2b6ee3a1104057df20ec3be61b410441eMon P Wang unsigned minNumElts = std::min(numEltsFrom, numEltsTo); 753ddf9abf2b6ee3a1104057df20ec3be61b410441eMon P Wang unsigned i; 754ddf9abf2b6ee3a1104057df20ec3be61b410441eMon P Wang for (i=0; i != minNumElts; ++i) 755481823aa819ea1dd25567ae616dca93056ef770aMon P Wang Args.push_back(ConstantInt::get(Int32Ty, i)); 756ddf9abf2b6ee3a1104057df20ec3be61b410441eMon P Wang 757ddf9abf2b6ee3a1104057df20ec3be61b410441eMon P Wang if (i < numEltsTo) { 758481823aa819ea1dd25567ae616dca93056ef770aMon P Wang Constant* UnC = UndefValue::get(Int32Ty); 759ddf9abf2b6ee3a1104057df20ec3be61b410441eMon P Wang for (; i != numEltsTo; ++i) 760ddf9abf2b6ee3a1104057df20ec3be61b410441eMon P Wang Args.push_back(UnC); 761ddf9abf2b6ee3a1104057df20ec3be61b410441eMon P Wang } 762ddf9abf2b6ee3a1104057df20ec3be61b410441eMon P Wang Constant *Mask = ConstantVector::get(Args); 763ddf9abf2b6ee3a1104057df20ec3be61b410441eMon P Wang return Builder.CreateShuffleVector(FromVal, UnV, Mask, "tmpV"); 764ddf9abf2b6ee3a1104057df20ec3be61b410441eMon P Wang} 765ddf9abf2b6ee3a1104057df20ec3be61b410441eMon P Wang 7664cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// ConvertScalar_ExtractValue - Extract a value of type ToType from an integer 7674cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// or vector value FromVal, extracting the bits from the offset specified by 7684cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// Offset. This returns the value, which is of type ToType. 7694cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// 7704cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// This happens when we are converting an "integer union" to a single 7714cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// integer scalar, or when we are converting a "vector union" to a vector with 7724cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// insert/extractelement instructions. 7734cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// 7744cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// Offset is an offset from the original alloca, in bits that need to be 7754cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// shifted to the right. 7764cc576bc5ea27951f3bb15ccefbe483293bf8eafChris LattnerValue *ConvertToScalarInfo:: 7774cc576bc5ea27951f3bb15ccefbe483293bf8eafChris LattnerConvertScalar_ExtractValue(Value *FromVal, const Type *ToType, 7784cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t Offset, IRBuilder<> &Builder) { 7794cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If the load is of the whole new alloca, no conversion is needed. 780be0761c8202405cdd33f1103d262c0aa97895a8eMon P Wang const Type *FromType = FromVal->getType(); 781be0761c8202405cdd33f1103d262c0aa97895a8eMon P Wang if (FromType == ToType && Offset == 0) 7824cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return FromVal; 7834cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 7844cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If the result alloca is a vector type, this is either an element 7854cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // access or a bitcast to another vector type of the same size. 786be0761c8202405cdd33f1103d262c0aa97895a8eMon P Wang if (const VectorType *VTy = dyn_cast<VectorType>(FromType)) { 7870398d6135daef709f80837e457a75dc2e1c2aab7Cameron Zwarich unsigned FromTypeSize = TD.getTypeAllocSize(FromType); 7889827b78b51f285e90c2b1e5add9b28d10c88595cCameron Zwarich unsigned ToTypeSize = TD.getTypeAllocSize(ToType); 7890398d6135daef709f80837e457a75dc2e1c2aab7Cameron Zwarich if (FromTypeSize == ToTypeSize) { 790ddf9abf2b6ee3a1104057df20ec3be61b410441eMon P Wang // If the two types have the same primitive size, use a bit cast. 791ddf9abf2b6ee3a1104057df20ec3be61b410441eMon P Wang // Otherwise, it is two vectors with the same element type that has 792ddf9abf2b6ee3a1104057df20ec3be61b410441eMon P Wang // the same allocation size but different number of elements so use 793ddf9abf2b6ee3a1104057df20ec3be61b410441eMon P Wang // a shuffle vector. 794be0761c8202405cdd33f1103d262c0aa97895a8eMon P Wang if (FromType->getPrimitiveSizeInBits() == 795be0761c8202405cdd33f1103d262c0aa97895a8eMon P Wang ToType->getPrimitiveSizeInBits()) 796be0761c8202405cdd33f1103d262c0aa97895a8eMon P Wang return Builder.CreateBitCast(FromVal, ToType, "tmp"); 797ddf9abf2b6ee3a1104057df20ec3be61b410441eMon P Wang else 798ddf9abf2b6ee3a1104057df20ec3be61b410441eMon P Wang return CreateShuffleVectorCast(FromVal, ToType, Builder); 799be0761c8202405cdd33f1103d262c0aa97895a8eMon P Wang } 800032c10fee2a4bb731488ce75844878009d3bd409Cameron Zwarich 8010398d6135daef709f80837e457a75dc2e1c2aab7Cameron Zwarich if (isPowerOf2_64(FromTypeSize / ToTypeSize)) { 802344731c01805aeda49c747bac6148501fa85557cCameron Zwarich assert(!(ToType->isVectorTy() && Offset != 0) && "Can't extract a value " 803344731c01805aeda49c747bac6148501fa85557cCameron Zwarich "of a smaller vector type at a nonzero offset."); 804032c10fee2a4bb731488ce75844878009d3bd409Cameron Zwarich 805344731c01805aeda49c747bac6148501fa85557cCameron Zwarich const Type *CastElementTy = getScaledElementType(FromType, ToType, 8061537ce75ed25bbca58096383bb1fb9dd427bf1aaCameron Zwarich ToTypeSize * 8); 8070398d6135daef709f80837e457a75dc2e1c2aab7Cameron Zwarich unsigned NumCastVectorElements = FromTypeSize / ToTypeSize; 808032c10fee2a4bb731488ce75844878009d3bd409Cameron Zwarich 809032c10fee2a4bb731488ce75844878009d3bd409Cameron Zwarich LLVMContext &Context = FromVal->getContext(); 810032c10fee2a4bb731488ce75844878009d3bd409Cameron Zwarich const Type *CastTy = VectorType::get(CastElementTy, 811032c10fee2a4bb731488ce75844878009d3bd409Cameron Zwarich NumCastVectorElements); 812032c10fee2a4bb731488ce75844878009d3bd409Cameron Zwarich Value *Cast = Builder.CreateBitCast(FromVal, CastTy, "tmp"); 813344731c01805aeda49c747bac6148501fa85557cCameron Zwarich 814344731c01805aeda49c747bac6148501fa85557cCameron Zwarich unsigned EltSize = TD.getTypeAllocSizeInBits(CastElementTy); 815344731c01805aeda49c747bac6148501fa85557cCameron Zwarich unsigned Elt = Offset/EltSize; 816344731c01805aeda49c747bac6148501fa85557cCameron Zwarich assert(EltSize*Elt == Offset && "Invalid modulus in validity checking"); 817032c10fee2a4bb731488ce75844878009d3bd409Cameron Zwarich Value *Extract = Builder.CreateExtractElement(Cast, ConstantInt::get( 818344731c01805aeda49c747bac6148501fa85557cCameron Zwarich Type::getInt32Ty(Context), Elt), "tmp"); 819032c10fee2a4bb731488ce75844878009d3bd409Cameron Zwarich return Builder.CreateBitCast(Extract, ToType, "tmp"); 820b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich } 8214cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 8224cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Otherwise it must be an element access. 8234cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner unsigned Elt = 0; 8244cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (Offset) { 8254cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner unsigned EltSize = TD.getTypeAllocSizeInBits(VTy->getElementType()); 8264cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Elt = Offset/EltSize; 8274cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner assert(EltSize*Elt == Offset && "Invalid modulus in validity checking"); 828b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson } 8294cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Return the element extracted out of it. 8304cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *V = Builder.CreateExtractElement(FromVal, ConstantInt::get( 8314cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Type::getInt32Ty(FromVal->getContext()), Elt), "tmp"); 8324cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (V->getType() != ToType) 8334cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner V = Builder.CreateBitCast(V, ToType, "tmp"); 8344cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return V; 8354cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 8366974302e3ff20746268721959efed807c7711bfcBob Wilson 8374cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If ToType is a first class aggregate, extract out each of the pieces and 8384cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // use insertvalue's to form the FCA. 8394cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (const StructType *ST = dyn_cast<StructType>(ToType)) { 8404cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner const StructLayout &Layout = *TD.getStructLayout(ST); 8414cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *Res = UndefValue::get(ST); 8424cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner for (unsigned i = 0, e = ST->getNumElements(); i != e; ++i) { 8434cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *Elt = ConvertScalar_ExtractValue(FromVal, ST->getElementType(i), 8444cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Offset+Layout.getElementOffsetInBits(i), 8454cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Builder); 8464cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Res = Builder.CreateInsertValue(Res, Elt, i, "tmp"); 8474cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 8484cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return Res; 8494cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 8506974302e3ff20746268721959efed807c7711bfcBob Wilson 8514cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (const ArrayType *AT = dyn_cast<ArrayType>(ToType)) { 8524cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t EltSize = TD.getTypeAllocSizeInBits(AT->getElementType()); 8534cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *Res = UndefValue::get(AT); 8544cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner for (unsigned i = 0, e = AT->getNumElements(); i != e; ++i) { 8554cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *Elt = ConvertScalar_ExtractValue(FromVal, AT->getElementType(), 8564cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Offset+i*EltSize, Builder); 8574cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Res = Builder.CreateInsertValue(Res, Elt, i, "tmp"); 8584cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 8594cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return Res; 860b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson } 8612674089cefe519195e00bdf879647438cfb1cb0fDaniel Dunbar 8624cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Otherwise, this must be a union that was converted to an integer value. 8634cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner const IntegerType *NTy = cast<IntegerType>(FromVal->getType()); 864b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson 8654cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If this is a big-endian system and the load is narrower than the 8664cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // full alloca type, we need to do a shift to get the right bits. 8674cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner int ShAmt = 0; 8684cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (TD.isBigEndian()) { 8694cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // On big-endian machines, the lowest bit is stored at the bit offset 8704cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // from the pointer given by getTypeStoreSizeInBits. This matters for 8714cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // integers with a bitwidth that is not a multiple of 8. 8724cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner ShAmt = TD.getTypeStoreSizeInBits(NTy) - 8734cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner TD.getTypeStoreSizeInBits(ToType) - Offset; 874b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson } else { 8754cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner ShAmt = Offset; 876b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson } 877b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson 8784cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Note: we support negative bitwidths (with shl) which are not defined. 8794cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // We do this to support (f.e.) loads off the end of a structure where 8804cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // only some bits are used. 8814cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (ShAmt > 0 && (unsigned)ShAmt < NTy->getBitWidth()) 8824cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner FromVal = Builder.CreateLShr(FromVal, 8834cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner ConstantInt::get(FromVal->getType(), 8844cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner ShAmt), "tmp"); 8854cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner else if (ShAmt < 0 && (unsigned)-ShAmt < NTy->getBitWidth()) 8866974302e3ff20746268721959efed807c7711bfcBob Wilson FromVal = Builder.CreateShl(FromVal, 8874cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner ConstantInt::get(FromVal->getType(), 8884cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner -ShAmt), "tmp"); 889b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson 8904cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Finally, unconditionally truncate the integer to the right width. 8914cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner unsigned LIBitWidth = TD.getTypeSizeInBits(ToType); 8924cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (LIBitWidth < NTy->getBitWidth()) 8934cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner FromVal = 8946974302e3ff20746268721959efed807c7711bfcBob Wilson Builder.CreateTrunc(FromVal, IntegerType::get(FromVal->getContext(), 8954cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner LIBitWidth), "tmp"); 8964cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner else if (LIBitWidth > NTy->getBitWidth()) 8974cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner FromVal = 8986974302e3ff20746268721959efed807c7711bfcBob Wilson Builder.CreateZExt(FromVal, IntegerType::get(FromVal->getContext(), 8994cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner LIBitWidth), "tmp"); 9004cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 9014cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If the result is an integer, this is a trunc or bitcast. 9024cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (ToType->isIntegerTy()) { 9034cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Should be done. 9044cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } else if (ToType->isFloatingPointTy() || ToType->isVectorTy()) { 9054cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Just do a bitcast, we know the sizes match up. 9064cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner FromVal = Builder.CreateBitCast(FromVal, ToType, "tmp"); 9074cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } else { 9084cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Otherwise must be a pointer. 9094cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner FromVal = Builder.CreateIntToPtr(FromVal, ToType, "tmp"); 910372dda8881c7a32a6f5ce0f76a713e3a9ef46ea1Chris Lattner } 9114cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner assert(FromVal->getType() == ToType && "Didn't convert right?"); 9124cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return FromVal; 913372dda8881c7a32a6f5ce0f76a713e3a9ef46ea1Chris Lattner} 914372dda8881c7a32a6f5ce0f76a713e3a9ef46ea1Chris Lattner 9154cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// ConvertScalar_InsertValue - Insert the value "SV" into the existing integer 9164cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// or vector value "Old" at the offset specified by Offset. 9174cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// 9184cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// This happens when we are converting an "integer union" to a 9194cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// single integer scalar, or when we are converting a "vector union" to a 9204cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// vector with insert/extractelement instructions. 9214cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// 9224cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// Offset is an offset from the original alloca, in bits that need to be 9234cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// shifted to the right. 9244cc576bc5ea27951f3bb15ccefbe483293bf8eafChris LattnerValue *ConvertToScalarInfo:: 9254cc576bc5ea27951f3bb15ccefbe483293bf8eafChris LattnerConvertScalar_InsertValue(Value *SV, Value *Old, 9264cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t Offset, IRBuilder<> &Builder) { 9274cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Convert the stored type to the actual type, shift it left to insert 9284cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // then 'or' into place. 9294cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner const Type *AllocaType = Old->getType(); 9304cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner LLVMContext &Context = Old->getContext(); 9312674089cefe519195e00bdf879647438cfb1cb0fDaniel Dunbar 9324cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (const VectorType *VTy = dyn_cast<VectorType>(AllocaType)) { 9334cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t VecSize = TD.getTypeAllocSizeInBits(VTy); 9344cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t ValSize = TD.getTypeAllocSizeInBits(SV->getType()); 9356974302e3ff20746268721959efed807c7711bfcBob Wilson 9364cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Changing the whole vector with memset or with an access of a different 9374cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // vector type? 938be0761c8202405cdd33f1103d262c0aa97895a8eMon P Wang if (ValSize == VecSize) { 939ddf9abf2b6ee3a1104057df20ec3be61b410441eMon P Wang // If the two types have the same primitive size, use a bit cast. 940ddf9abf2b6ee3a1104057df20ec3be61b410441eMon P Wang // Otherwise, it is two vectors with the same element type that has 941ddf9abf2b6ee3a1104057df20ec3be61b410441eMon P Wang // the same allocation size but different number of elements so use 942ddf9abf2b6ee3a1104057df20ec3be61b410441eMon P Wang // a shuffle vector. 943be0761c8202405cdd33f1103d262c0aa97895a8eMon P Wang if (VTy->getPrimitiveSizeInBits() == 944be0761c8202405cdd33f1103d262c0aa97895a8eMon P Wang SV->getType()->getPrimitiveSizeInBits()) 945be0761c8202405cdd33f1103d262c0aa97895a8eMon P Wang return Builder.CreateBitCast(SV, AllocaType, "tmp"); 946ddf9abf2b6ee3a1104057df20ec3be61b410441eMon P Wang else 947ddf9abf2b6ee3a1104057df20ec3be61b410441eMon P Wang return CreateShuffleVectorCast(SV, VTy, Builder); 948be0761c8202405cdd33f1103d262c0aa97895a8eMon P Wang } 9492674089cefe519195e00bdf879647438cfb1cb0fDaniel Dunbar 950344731c01805aeda49c747bac6148501fa85557cCameron Zwarich if (isPowerOf2_64(VecSize / ValSize)) { 951344731c01805aeda49c747bac6148501fa85557cCameron Zwarich assert(!(SV->getType()->isVectorTy() && Offset != 0) && "Can't insert a " 952344731c01805aeda49c747bac6148501fa85557cCameron Zwarich "value of a smaller vector type at a nonzero offset."); 953b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich 954344731c01805aeda49c747bac6148501fa85557cCameron Zwarich const Type *CastElementTy = getScaledElementType(VTy, SV->getType(), 955344731c01805aeda49c747bac6148501fa85557cCameron Zwarich ValSize); 9561537ce75ed25bbca58096383bb1fb9dd427bf1aaCameron Zwarich unsigned NumCastVectorElements = VecSize / ValSize; 957b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich 958b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich LLVMContext &Context = SV->getContext(); 959b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich const Type *OldCastTy = VectorType::get(CastElementTy, 960b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich NumCastVectorElements); 961b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich Value *OldCast = Builder.CreateBitCast(Old, OldCastTy, "tmp"); 962b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich 963b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich Value *SVCast = Builder.CreateBitCast(SV, CastElementTy, "tmp"); 964344731c01805aeda49c747bac6148501fa85557cCameron Zwarich 965344731c01805aeda49c747bac6148501fa85557cCameron Zwarich unsigned EltSize = TD.getTypeAllocSizeInBits(CastElementTy); 966344731c01805aeda49c747bac6148501fa85557cCameron Zwarich unsigned Elt = Offset/EltSize; 967344731c01805aeda49c747bac6148501fa85557cCameron Zwarich assert(EltSize*Elt == Offset && "Invalid modulus in validity checking"); 968b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich Value *Insert = 969b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich Builder.CreateInsertElement(OldCast, SVCast, ConstantInt::get( 970344731c01805aeda49c747bac6148501fa85557cCameron Zwarich Type::getInt32Ty(Context), Elt), "tmp"); 971b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich return Builder.CreateBitCast(Insert, AllocaType, "tmp"); 972b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich } 973b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich 9744cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Must be an element insertion. 975c5c43b958cf2f251c836f94d4499adb6296f0611Cameron Zwarich assert(SV->getType() == VTy->getElementType()); 976c5c43b958cf2f251c836f94d4499adb6296f0611Cameron Zwarich uint64_t EltSize = TD.getTypeAllocSizeInBits(VTy->getElementType()); 9774cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner unsigned Elt = Offset/EltSize; 978c5c43b958cf2f251c836f94d4499adb6296f0611Cameron Zwarich return Builder.CreateInsertElement(Old, SV, 9794cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner ConstantInt::get(Type::getInt32Ty(SV->getContext()), Elt), 9804cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner "tmp"); 981b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson } 9826974302e3ff20746268721959efed807c7711bfcBob Wilson 9834cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If SV is a first-class aggregate value, insert each value recursively. 9844cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (const StructType *ST = dyn_cast<StructType>(SV->getType())) { 9854cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner const StructLayout &Layout = *TD.getStructLayout(ST); 9864cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner for (unsigned i = 0, e = ST->getNumElements(); i != e; ++i) { 9874cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *Elt = Builder.CreateExtractValue(SV, i, "tmp"); 9886974302e3ff20746268721959efed807c7711bfcBob Wilson Old = ConvertScalar_InsertValue(Elt, Old, 9894cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Offset+Layout.getElementOffsetInBits(i), 9904cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Builder); 9914cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 9924cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return Old; 9934cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 9946974302e3ff20746268721959efed807c7711bfcBob Wilson 9954cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (const ArrayType *AT = dyn_cast<ArrayType>(SV->getType())) { 9964cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t EltSize = TD.getTypeAllocSizeInBits(AT->getElementType()); 9974cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner for (unsigned i = 0, e = AT->getNumElements(); i != e; ++i) { 9984cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *Elt = Builder.CreateExtractValue(SV, i, "tmp"); 9994cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Old = ConvertScalar_InsertValue(Elt, Old, Offset+i*EltSize, Builder); 10004cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 10014cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return Old; 10024cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 10034cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 10044cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If SV is a float, convert it to the appropriate integer type. 10054cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If it is a pointer, do the same. 10064cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner unsigned SrcWidth = TD.getTypeSizeInBits(SV->getType()); 10074cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner unsigned DestWidth = TD.getTypeSizeInBits(AllocaType); 10084cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner unsigned SrcStoreWidth = TD.getTypeStoreSizeInBits(SV->getType()); 10094cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner unsigned DestStoreWidth = TD.getTypeStoreSizeInBits(AllocaType); 10104cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (SV->getType()->isFloatingPointTy() || SV->getType()->isVectorTy()) 10114cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner SV = Builder.CreateBitCast(SV, 10124cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner IntegerType::get(SV->getContext(),SrcWidth), "tmp"); 10134cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner else if (SV->getType()->isPointerTy()) 10144cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner SV = Builder.CreatePtrToInt(SV, TD.getIntPtrType(SV->getContext()), "tmp"); 10154cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 10164cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Zero extend or truncate the value if needed. 10174cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (SV->getType() != AllocaType) { 10184cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (SV->getType()->getPrimitiveSizeInBits() < 10194cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner AllocaType->getPrimitiveSizeInBits()) 10204cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner SV = Builder.CreateZExt(SV, AllocaType, "tmp"); 10214cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner else { 10224cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Truncation may be needed if storing more than the alloca can hold 10234cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // (undefined behavior). 10244cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner SV = Builder.CreateTrunc(SV, AllocaType, "tmp"); 10254cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner SrcWidth = DestWidth; 10264cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner SrcStoreWidth = DestStoreWidth; 10274cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 10284cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 10294cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 10304cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If this is a big-endian system and the store is narrower than the 10314cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // full alloca type, we need to do a shift to get the right bits. 10324cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner int ShAmt = 0; 10334cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (TD.isBigEndian()) { 10344cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // On big-endian machines, the lowest bit is stored at the bit offset 10354cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // from the pointer given by getTypeStoreSizeInBits. This matters for 10364cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // integers with a bitwidth that is not a multiple of 8. 10374cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner ShAmt = DestStoreWidth - SrcStoreWidth - Offset; 10384cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } else { 10394cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner ShAmt = Offset; 10404cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 10414cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 10424cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Note: we support negative bitwidths (with shr) which are not defined. 10434cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // We do this to support (f.e.) stores off the end of a structure where 10444cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // only some bits in the structure are set. 10454cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner APInt Mask(APInt::getLowBitsSet(DestWidth, SrcWidth)); 10464cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (ShAmt > 0 && (unsigned)ShAmt < DestWidth) { 10474cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner SV = Builder.CreateShl(SV, ConstantInt::get(SV->getType(), 10484cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner ShAmt), "tmp"); 10494cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Mask <<= ShAmt; 10504cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } else if (ShAmt < 0 && (unsigned)-ShAmt < DestWidth) { 10514cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner SV = Builder.CreateLShr(SV, ConstantInt::get(SV->getType(), 10524cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner -ShAmt), "tmp"); 10534cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Mask = Mask.lshr(-ShAmt); 10544cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 10554cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 10564cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Mask out the bits we are about to insert from the old value, and or 10574cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // in the new bits. 10584cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (SrcWidth != DestWidth) { 10594cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner assert(DestWidth > SrcWidth); 10604cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Old = Builder.CreateAnd(Old, ConstantInt::get(Context, ~Mask), "mask"); 10614cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner SV = Builder.CreateOr(Old, SV, "ins"); 10624cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 10634cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return SV; 1064b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson} 1065b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson 1066b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson 10674cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner//===----------------------------------------------------------------------===// 10684cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner// SRoA Driver 10694cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner//===----------------------------------------------------------------------===// 1070b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson 1071b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson 10724cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattnerbool SROA::runOnFunction(Function &F) { 10734cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner TD = getAnalysisIfAvailable<TargetData>(); 1074b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson 10754cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner bool Changed = performPromotion(F); 1076b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson 10774cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // FIXME: ScalarRepl currently depends on TargetData more than it 10784cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // theoretically needs to. It should be refactored in order to support 10794cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // target-independent IR. Until this is done, just skip the actual 10804cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // scalar-replacement portion of this pass. 10814cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (!TD) return Changed; 10824cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 10834cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner while (1) { 10844cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner bool LocalChange = performScalarRepl(F); 10854cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (!LocalChange) break; // No need to repromote if no scalarrepl 10864cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Changed = true; 10874cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner LocalChange = performPromotion(F); 10884cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (!LocalChange) break; // No need to re-scalarrepl if no promotion 10892674089cefe519195e00bdf879647438cfb1cb0fDaniel Dunbar } 10904cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 10914cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return Changed; 1092d93afec1dbbb1abb3df55e2e007b5f256d09f84aChris Lattner} 1093d93afec1dbbb1abb3df55e2e007b5f256d09f84aChris Lattner 1094d0f56132cfa6e25fb9692e84ea12444c86b92ae4Chris Lattnernamespace { 1095d0f56132cfa6e25fb9692e84ea12444c86b92ae4Chris Lattnerclass AllocaPromoter : public LoadAndStorePromoter { 1096d0f56132cfa6e25fb9692e84ea12444c86b92ae4Chris Lattner AllocaInst *AI; 1097d0f56132cfa6e25fb9692e84ea12444c86b92ae4Chris Lattnerpublic: 1098c827939046670a9800659b83e2048f1d3a79a531Cameron Zwarich AllocaPromoter(const SmallVectorImpl<Instruction*> &Insts, SSAUpdater &S, 1099c827939046670a9800659b83e2048f1d3a79a531Cameron Zwarich DbgDeclareInst *DD, DIBuilder *&DB) 1100c827939046670a9800659b83e2048f1d3a79a531Cameron Zwarich : LoadAndStorePromoter(Insts, S, DD, DB), AI(0) {} 1101e0a1a5ba91df6817f9ffae7af65ed0bda66f7620Chris Lattner 1102deaf55f69865bbc997a569c2a689ec5b0fbdefefChris Lattner void run(AllocaInst *AI, const SmallVectorImpl<Instruction*> &Insts) { 1103d0f56132cfa6e25fb9692e84ea12444c86b92ae4Chris Lattner // Remember which alloca we're promoting (for isInstInList). 1104d0f56132cfa6e25fb9692e84ea12444c86b92ae4Chris Lattner this->AI = AI; 1105deaf55f69865bbc997a569c2a689ec5b0fbdefefChris Lattner LoadAndStorePromoter::run(Insts); 1106d0f56132cfa6e25fb9692e84ea12444c86b92ae4Chris Lattner AI->eraseFromParent(); 1107e0a1a5ba91df6817f9ffae7af65ed0bda66f7620Chris Lattner } 1108e0a1a5ba91df6817f9ffae7af65ed0bda66f7620Chris Lattner 1109d0f56132cfa6e25fb9692e84ea12444c86b92ae4Chris Lattner virtual bool isInstInList(Instruction *I, 1110d0f56132cfa6e25fb9692e84ea12444c86b92ae4Chris Lattner const SmallVectorImpl<Instruction*> &Insts) const { 1111d0f56132cfa6e25fb9692e84ea12444c86b92ae4Chris Lattner if (LoadInst *LI = dyn_cast<LoadInst>(I)) 1112d0f56132cfa6e25fb9692e84ea12444c86b92ae4Chris Lattner return LI->getOperand(0) == AI; 1113d0f56132cfa6e25fb9692e84ea12444c86b92ae4Chris Lattner return cast<StoreInst>(I)->getPointerOperand() == AI; 1114e0a1a5ba91df6817f9ffae7af65ed0bda66f7620Chris Lattner } 1115d0f56132cfa6e25fb9692e84ea12444c86b92ae4Chris Lattner}; 1116d0f56132cfa6e25fb9692e84ea12444c86b92ae4Chris Lattner} // end anon namespace 111778c50b8cd68d266d4ed6f8eca443cf8142a01204Bob Wilson 1118c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner/// isSafeSelectToSpeculate - Select instructions that use an alloca and are 1119c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner/// subsequently loaded can be rewritten to load both input pointers and then 1120c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner/// select between the result, allowing the load of the alloca to be promoted. 1121c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner/// From this: 1122c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner/// %P2 = select i1 %cond, i32* %Alloca, i32* %Other 1123c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner/// %V = load i32* %P2 1124c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner/// to: 1125c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner/// %V1 = load i32* %Alloca -> will be mem2reg'd 1126c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner/// %V2 = load i32* %Other 1127e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner/// %V = select i1 %cond, i32 %V1, i32 %V2 1128c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner/// 1129c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner/// We can do this to a select if its only uses are loads and if the operand to 1130c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner/// the select can be loaded unconditionally. 1131c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattnerstatic bool isSafeSelectToSpeculate(SelectInst *SI, const TargetData *TD) { 1132c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner bool TDerefable = SI->getTrueValue()->isDereferenceablePointer(); 1133c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner bool FDerefable = SI->getFalseValue()->isDereferenceablePointer(); 1134c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner 1135c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner for (Value::use_iterator UI = SI->use_begin(), UE = SI->use_end(); 1136c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner UI != UE; ++UI) { 1137c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner LoadInst *LI = dyn_cast<LoadInst>(*UI); 1138c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner if (LI == 0 || LI->isVolatile()) return false; 1139c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner 1140e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // Both operands to the select need to be dereferencable, either absolutely 1141c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner // (e.g. allocas) or at this point because we can see other accesses to it. 1142c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner if (!TDerefable && !isSafeToLoadUnconditionally(SI->getTrueValue(), LI, 1143c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner LI->getAlignment(), TD)) 1144c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner return false; 1145c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner if (!FDerefable && !isSafeToLoadUnconditionally(SI->getFalseValue(), LI, 1146c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner LI->getAlignment(), TD)) 1147c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner return false; 1148c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner } 1149c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner 1150c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner return true; 1151c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner} 1152c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner 1153e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner/// isSafePHIToSpeculate - PHI instructions that use an alloca and are 1154e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner/// subsequently loaded can be rewritten to load both input pointers in the pred 1155e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner/// blocks and then PHI the results, allowing the load of the alloca to be 1156e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner/// promoted. 1157e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner/// From this: 1158e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner/// %P2 = phi [i32* %Alloca, i32* %Other] 1159e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner/// %V = load i32* %P2 1160e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner/// to: 1161e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner/// %V1 = load i32* %Alloca -> will be mem2reg'd 1162e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner/// ... 1163e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner/// %V2 = load i32* %Other 1164e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner/// ... 1165e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner/// %V = phi [i32 %V1, i32 %V2] 1166e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner/// 1167e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner/// We can do this to a select if its only uses are loads and if the operand to 1168e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner/// the select can be loaded unconditionally. 1169e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattnerstatic bool isSafePHIToSpeculate(PHINode *PN, const TargetData *TD) { 1170e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // For now, we can only do this promotion if the load is in the same block as 1171e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // the PHI, and if there are no stores between the phi and load. 1172e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // TODO: Allow recursive phi users. 1173e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // TODO: Allow stores. 1174e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner BasicBlock *BB = PN->getParent(); 1175e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner unsigned MaxAlign = 0; 1176e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner for (Value::use_iterator UI = PN->use_begin(), UE = PN->use_end(); 1177e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner UI != UE; ++UI) { 1178e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner LoadInst *LI = dyn_cast<LoadInst>(*UI); 1179e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner if (LI == 0 || LI->isVolatile()) return false; 1180e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner 1181e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // For now we only allow loads in the same block as the PHI. This is a 1182e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // common case that happens when instcombine merges two loads through a PHI. 1183e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner if (LI->getParent() != BB) return false; 1184e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner 1185e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // Ensure that there are no instructions between the PHI and the load that 1186e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // could store. 1187e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner for (BasicBlock::iterator BBI = PN; &*BBI != LI; ++BBI) 1188e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner if (BBI->mayWriteToMemory()) 1189e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner return false; 1190e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner 1191e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner MaxAlign = std::max(MaxAlign, LI->getAlignment()); 1192e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner } 1193e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner 1194e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // Okay, we know that we have one or more loads in the same block as the PHI. 1195e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // We can transform this if it is safe to push the loads into the predecessor 1196e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // blocks. The only thing to watch out for is that we can't put a possibly 1197e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // trapping load in the predecessor if it is a critical edge. 1198e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i) { 1199e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner BasicBlock *Pred = PN->getIncomingBlock(i); 1200e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner 1201e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // If the predecessor has a single successor, then the edge isn't critical. 1202e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner if (Pred->getTerminator()->getNumSuccessors() == 1) 1203e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner continue; 1204e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner 1205e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner Value *InVal = PN->getIncomingValue(i); 1206e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner 1207e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // If the InVal is an invoke in the pred, we can't put a load on the edge. 1208e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner if (InvokeInst *II = dyn_cast<InvokeInst>(InVal)) 1209e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner if (II->getParent() == Pred) 1210e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner return false; 1211e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner 1212e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // If this pointer is always safe to load, or if we can prove that there is 1213e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // already a load in the block, then we can move the load to the pred block. 1214e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner if (InVal->isDereferenceablePointer() || 1215e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner isSafeToLoadUnconditionally(InVal, Pred->getTerminator(), MaxAlign, TD)) 1216e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner continue; 1217e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner 1218e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner return false; 1219e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner } 1220e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner 1221e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner return true; 1222e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner} 1223e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner 1224c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner 1225c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner/// tryToMakeAllocaBePromotable - This returns true if the alloca only has 1226c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner/// direct (non-volatile) loads and stores to it. If the alloca is close but 1227c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner/// not quite there, this will transform the code to allow promotion. As such, 1228c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner/// it is a non-pure predicate. 1229c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattnerstatic bool tryToMakeAllocaBePromotable(AllocaInst *AI, const TargetData *TD) { 1230c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner SetVector<Instruction*, SmallVector<Instruction*, 4>, 1231c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner SmallPtrSet<Instruction*, 4> > InstsToRewrite; 1232c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner 1233c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner for (Value::use_iterator UI = AI->use_begin(), UE = AI->use_end(); 1234c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner UI != UE; ++UI) { 1235c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner User *U = *UI; 1236c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner if (LoadInst *LI = dyn_cast<LoadInst>(U)) { 1237c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner if (LI->isVolatile()) 1238c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner return false; 1239c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner continue; 1240c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner } 1241c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner 1242c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner if (StoreInst *SI = dyn_cast<StoreInst>(U)) { 1243c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner if (SI->getOperand(0) == AI || SI->isVolatile()) 1244c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner return false; // Don't allow a store OF the AI, only INTO the AI. 1245c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner continue; 1246c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner } 1247c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner 1248c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner if (SelectInst *SI = dyn_cast<SelectInst>(U)) { 1249c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner // If the condition being selected on is a constant, fold the select, yes 1250c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner // this does (rarely) happen early on. 1251c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner if (ConstantInt *CI = dyn_cast<ConstantInt>(SI->getCondition())) { 1252c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner Value *Result = SI->getOperand(1+CI->isZero()); 1253c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner SI->replaceAllUsesWith(Result); 1254c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner SI->eraseFromParent(); 1255c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner 1256c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner // This is very rare and we just scrambled the use list of AI, start 1257c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner // over completely. 1258c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner return tryToMakeAllocaBePromotable(AI, TD); 1259c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner } 1260c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner 1261c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner // If it is safe to turn "load (select c, AI, ptr)" into a select of two 1262c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner // loads, then we can transform this by rewriting the select. 1263c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner if (!isSafeSelectToSpeculate(SI, TD)) 1264c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner return false; 1265c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner 1266c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner InstsToRewrite.insert(SI); 1267c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner continue; 1268c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner } 1269c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner 1270e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner if (PHINode *PN = dyn_cast<PHINode>(U)) { 1271e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner if (PN->use_empty()) { // Dead PHIs can be stripped. 1272e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner InstsToRewrite.insert(PN); 1273e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner continue; 1274e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner } 1275e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner 1276e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // If it is safe to turn "load (phi [AI, ptr, ...])" into a PHI of loads 1277e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // in the pred blocks, then we can transform this by rewriting the PHI. 1278e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner if (!isSafePHIToSpeculate(PN, TD)) 1279e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner return false; 1280e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner 1281e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner InstsToRewrite.insert(PN); 1282e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner continue; 1283e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner } 1284e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner 1285c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner return false; 1286c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner } 1287c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner 1288c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner // If there are no instructions to rewrite, then all uses are load/stores and 1289c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner // we're done! 1290c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner if (InstsToRewrite.empty()) 1291c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner return true; 1292c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner 1293c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner // If we have instructions that need to be rewritten for this to be promotable 1294c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner // take care of it now. 1295c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner for (unsigned i = 0, e = InstsToRewrite.size(); i != e; ++i) { 1296e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner if (SelectInst *SI = dyn_cast<SelectInst>(InstsToRewrite[i])) { 1297e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // Selects in InstsToRewrite only have load uses. Rewrite each as two 1298e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // loads with a new select. 1299e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner while (!SI->use_empty()) { 1300e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner LoadInst *LI = cast<LoadInst>(SI->use_back()); 1301c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner 1302e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner IRBuilder<> Builder(LI); 1303e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner LoadInst *TrueLoad = 1304e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner Builder.CreateLoad(SI->getTrueValue(), LI->getName()+".t"); 1305e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner LoadInst *FalseLoad = 1306394d1f1948c1b5c9e902059104b08a4837dfbbeeNick Lewycky Builder.CreateLoad(SI->getFalseValue(), LI->getName()+".f"); 1307e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner 1308e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // Transfer alignment and TBAA info if present. 1309e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner TrueLoad->setAlignment(LI->getAlignment()); 1310e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner FalseLoad->setAlignment(LI->getAlignment()); 1311e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner if (MDNode *Tag = LI->getMetadata(LLVMContext::MD_tbaa)) { 1312e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner TrueLoad->setMetadata(LLVMContext::MD_tbaa, Tag); 1313e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner FalseLoad->setMetadata(LLVMContext::MD_tbaa, Tag); 1314e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner } 1315e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner 1316e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner Value *V = Builder.CreateSelect(SI->getCondition(), TrueLoad, FalseLoad); 1317e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner V->takeName(LI); 1318e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner LI->replaceAllUsesWith(V); 1319e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner LI->eraseFromParent(); 1320c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner } 1321e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner 1322e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // Now that all the loads are gone, the select is gone too. 1323e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner SI->eraseFromParent(); 1324e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner continue; 1325e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner } 1326e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner 1327e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // Otherwise, we have a PHI node which allows us to push the loads into the 1328e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // predecessors. 1329e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner PHINode *PN = cast<PHINode>(InstsToRewrite[i]); 1330e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner if (PN->use_empty()) { 1331e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner PN->eraseFromParent(); 1332e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner continue; 1333e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner } 1334e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner 1335e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner const Type *LoadTy = cast<PointerType>(PN->getType())->getElementType(); 13363ecfc861b4365f341c5c969b40e1afccde676e6fJay Foad PHINode *NewPN = PHINode::Create(LoadTy, PN->getNumIncomingValues(), 13373ecfc861b4365f341c5c969b40e1afccde676e6fJay Foad PN->getName()+".ld", PN); 1338e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner 1339e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // Get the TBAA tag and alignment to use from one of the loads. It doesn't 1340e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // matter which one we get and if any differ, it doesn't matter. 1341e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner LoadInst *SomeLoad = cast<LoadInst>(PN->use_back()); 1342e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner MDNode *TBAATag = SomeLoad->getMetadata(LLVMContext::MD_tbaa); 1343e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner unsigned Align = SomeLoad->getAlignment(); 1344e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner 1345e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // Rewrite all loads of the PN to use the new PHI. 1346e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner while (!PN->use_empty()) { 1347e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner LoadInst *LI = cast<LoadInst>(PN->use_back()); 1348e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner LI->replaceAllUsesWith(NewPN); 1349c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner LI->eraseFromParent(); 1350c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner } 1351c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner 1352e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // Inject loads into all of the pred blocks. Keep track of which blocks we 1353e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // insert them into in case we have multiple edges from the same block. 1354e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner DenseMap<BasicBlock*, LoadInst*> InsertedLoads; 1355e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner 1356e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i) { 1357e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner BasicBlock *Pred = PN->getIncomingBlock(i); 1358e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner LoadInst *&Load = InsertedLoads[Pred]; 1359e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner if (Load == 0) { 1360e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner Load = new LoadInst(PN->getIncomingValue(i), 1361e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner PN->getName() + "." + Pred->getName(), 1362e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner Pred->getTerminator()); 1363e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner Load->setAlignment(Align); 1364e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner if (TBAATag) Load->setMetadata(LLVMContext::MD_tbaa, TBAATag); 1365e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner } 1366e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner 1367e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner NewPN->addIncoming(Load, Pred); 1368e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner } 1369e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner 1370e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner PN->eraseFromParent(); 1371c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner } 1372c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner 1373c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner ++NumAdjusted; 1374c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner return true; 1375c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner} 1376c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner 13774cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattnerbool SROA::performPromotion(Function &F) { 13784cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner std::vector<AllocaInst*> Allocas; 1379e0a1a5ba91df6817f9ffae7af65ed0bda66f7620Chris Lattner DominatorTree *DT = 0; 1380b1686c32fc694636cbf15a59b23b2a741b65ecf4Cameron Zwarich if (HasDomTree) 1381e0a1a5ba91df6817f9ffae7af65ed0bda66f7620Chris Lattner DT = &getAnalysis<DominatorTree>(); 1382b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson 13834cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner BasicBlock &BB = F.getEntryBlock(); // Get the entry node for the function 1384372dda8881c7a32a6f5ce0f76a713e3a9ef46ea1Chris Lattner 13854cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner bool Changed = false; 1386deaf55f69865bbc997a569c2a689ec5b0fbdefefChris Lattner SmallVector<Instruction*, 64> Insts; 1387c827939046670a9800659b83e2048f1d3a79a531Cameron Zwarich DIBuilder *DIB = 0; 13884cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner while (1) { 13894cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Allocas.clear(); 13904cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 13914cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Find allocas that are safe to promote, by looking at all instructions in 13924cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // the entry node 13934cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner for (BasicBlock::iterator I = BB.begin(), E = --BB.end(); I != E; ++I) 13944cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (AllocaInst *AI = dyn_cast<AllocaInst>(I)) // Is it an alloca? 1395c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner if (tryToMakeAllocaBePromotable(AI, TD)) 13964cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Allocas.push_back(AI); 13974cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 13984cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (Allocas.empty()) break; 13994cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 1400b1686c32fc694636cbf15a59b23b2a741b65ecf4Cameron Zwarich if (HasDomTree) 1401419e8a62997987e0509efe721c1ea81ac29f09f3Cameron Zwarich PromoteMemToReg(Allocas, *DT); 1402e0a1a5ba91df6817f9ffae7af65ed0bda66f7620Chris Lattner else { 1403e0a1a5ba91df6817f9ffae7af65ed0bda66f7620Chris Lattner SSAUpdater SSA; 1404deaf55f69865bbc997a569c2a689ec5b0fbdefefChris Lattner for (unsigned i = 0, e = Allocas.size(); i != e; ++i) { 1405deaf55f69865bbc997a569c2a689ec5b0fbdefefChris Lattner AllocaInst *AI = Allocas[i]; 1406deaf55f69865bbc997a569c2a689ec5b0fbdefefChris Lattner 1407deaf55f69865bbc997a569c2a689ec5b0fbdefefChris Lattner // Build list of instructions to promote. 1408deaf55f69865bbc997a569c2a689ec5b0fbdefefChris Lattner for (Value::use_iterator UI = AI->use_begin(), E = AI->use_end(); 1409deaf55f69865bbc997a569c2a689ec5b0fbdefefChris Lattner UI != E; ++UI) 1410deaf55f69865bbc997a569c2a689ec5b0fbdefefChris Lattner Insts.push_back(cast<Instruction>(*UI)); 1411c827939046670a9800659b83e2048f1d3a79a531Cameron Zwarich 1412c827939046670a9800659b83e2048f1d3a79a531Cameron Zwarich DbgDeclareInst *DDI = FindAllocaDbgDeclare(AI); 141313a16083abcdacf2ee44ae95b084f87937ea9aceCameron Zwarich if (DDI && !DIB) 141413a16083abcdacf2ee44ae95b084f87937ea9aceCameron Zwarich DIB = new DIBuilder(*AI->getParent()->getParent()->getParent()); 1415c827939046670a9800659b83e2048f1d3a79a531Cameron Zwarich AllocaPromoter(Insts, SSA, DDI, DIB).run(AI, Insts); 1416deaf55f69865bbc997a569c2a689ec5b0fbdefefChris Lattner Insts.clear(); 1417deaf55f69865bbc997a569c2a689ec5b0fbdefefChris Lattner } 1418e0a1a5ba91df6817f9ffae7af65ed0bda66f7620Chris Lattner } 14194cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner NumPromoted += Allocas.size(); 14204cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Changed = true; 14214cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 14224cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 1423c827939046670a9800659b83e2048f1d3a79a531Cameron Zwarich // FIXME: Is there a better way to handle the lazy initialization of DIB 1424c827939046670a9800659b83e2048f1d3a79a531Cameron Zwarich // so that there doesn't need to be an explicit delete? 1425c827939046670a9800659b83e2048f1d3a79a531Cameron Zwarich delete DIB; 1426c827939046670a9800659b83e2048f1d3a79a531Cameron Zwarich 14274cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return Changed; 14284cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner} 14294cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 14304cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 14314cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// ShouldAttemptScalarRepl - Decide if an alloca is a good candidate for 14324cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// SROA. It must be a struct or array type with a small number of elements. 14334cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattnerstatic bool ShouldAttemptScalarRepl(AllocaInst *AI) { 14344cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner const Type *T = AI->getAllocatedType(); 14354cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Do not promote any struct into more than 32 separate vars. 14364cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (const StructType *ST = dyn_cast<StructType>(T)) 14374cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return ST->getNumElements() <= 32; 14384cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Arrays are much less likely to be safe for SROA; only consider 14394cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // them if they are very small. 14404cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (const ArrayType *AT = dyn_cast<ArrayType>(T)) 14414cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return AT->getNumElements() <= 8; 14424cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return false; 14434cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner} 14444cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 14454cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 14464cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner// performScalarRepl - This algorithm is a simple worklist driven algorithm, 14479174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky// which runs on all of the alloca instructions in the function, removing them 14489174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky// if they are only used by getelementptr instructions. 14494cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner// 14504cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattnerbool SROA::performScalarRepl(Function &F) { 14514cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner std::vector<AllocaInst*> WorkList; 14524cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 14534cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Scan the entry basic block, adding allocas to the worklist. 14544cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner BasicBlock &BB = F.getEntryBlock(); 14554cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner for (BasicBlock::iterator I = BB.begin(), E = BB.end(); I != E; ++I) 14564cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (AllocaInst *A = dyn_cast<AllocaInst>(I)) 14574cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner WorkList.push_back(A); 14584cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 14594cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Process the worklist 14604cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner bool Changed = false; 14614cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner while (!WorkList.empty()) { 14624cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner AllocaInst *AI = WorkList.back(); 14634cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner WorkList.pop_back(); 14646974302e3ff20746268721959efed807c7711bfcBob Wilson 14654cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Handle dead allocas trivially. These can be formed by SROA'ing arrays 14664cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // with unused elements. 14674cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (AI->use_empty()) { 14684cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner AI->eraseFromParent(); 14694cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Changed = true; 14704cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner continue; 1471d93afec1dbbb1abb3df55e2e007b5f256d09f84aChris Lattner } 14724cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 14734cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If this alloca is impossible for us to promote, reject it early. 14744cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (AI->isArrayAllocation() || !AI->getAllocatedType()->isSized()) 14754cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner continue; 14766974302e3ff20746268721959efed807c7711bfcBob Wilson 14774cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Check to see if this allocation is only modified by a memcpy/memmove from 14784cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // a constant global. If this is the case, we can change all users to use 14794cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // the constant global instead. This is commonly produced by the CFE by 14804cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // constructs like "void foo() { int A[] = {1,2,3,4,5,6,7,8,9...}; }" if 'A' 14814cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // is only subsequently read. 14829174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky SmallVector<Instruction *, 4> ToDelete; 14839174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky if (MemTransferInst *Copy = isOnlyCopiedFromConstantGlobal(AI, ToDelete)) { 14844cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner DEBUG(dbgs() << "Found alloca equal to global: " << *AI << '\n'); 14859174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky DEBUG(dbgs() << " memcpy = " << *Copy << '\n'); 14869174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky for (unsigned i = 0, e = ToDelete.size(); i != e; ++i) 14879174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky ToDelete[i]->eraseFromParent(); 14889174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky Constant *TheSrc = cast<Constant>(Copy->getSource()); 14894cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner AI->replaceAllUsesWith(ConstantExpr::getBitCast(TheSrc, AI->getType())); 14909174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky Copy->eraseFromParent(); // Don't mutate the global. 14914cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner AI->eraseFromParent(); 14924cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner ++NumGlobals; 14934cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Changed = true; 14944cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner continue; 14954cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 14966974302e3ff20746268721959efed807c7711bfcBob Wilson 14974cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Check to see if we can perform the core SROA transformation. We cannot 14984cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // transform the allocation instruction if it is an array allocation 14994cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // (allocations OF arrays are ok though), and an allocation of a scalar 15004cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // value cannot be decomposed at all. 15014cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t AllocaSize = TD->getTypeAllocSize(AI->getAllocatedType()); 150244118f0e25c25fedda1ccdd6a72f072c0b5c96e7Dan Gohman 15034cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Do not promote [0 x %struct]. 15044cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (AllocaSize == 0) continue; 15056974302e3ff20746268721959efed807c7711bfcBob Wilson 15064cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Do not promote any struct whose size is too big. 15074cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (AllocaSize > SRThreshold) continue; 15086974302e3ff20746268721959efed807c7711bfcBob Wilson 15094cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If the alloca looks like a good candidate for scalar replacement, and if 15104cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // all its users can be transformed, then split up the aggregate into its 15114cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // separate elements. 15124cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (ShouldAttemptScalarRepl(AI) && isSafeAllocaToScalarRepl(AI)) { 15134cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner DoScalarReplacement(AI, WorkList); 15144cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Changed = true; 15154cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner continue; 151620adc9dc4650313f017b27d9818eb2176238113dMon P Wang } 15174cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 15184cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If we can turn this aggregate value (potentially with casts) into a 15194cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // simple scalar value that can be mem2reg'd into a register value. 15204cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // IsNotTrivial tracks whether this is something that mem2reg could have 15214cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // promoted itself. If so, we don't want to transform it needlessly. Note 15224cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // that we can't just check based on the type: the alloca may be of an i32 15234cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // but that has pointer arithmetic to set byte 3 of it or something. 15244cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (AllocaInst *NewAI = 15254cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner ConvertToScalarInfo((unsigned)AllocaSize, *TD).TryConvert(AI)) { 15264cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner NewAI->takeName(AI); 15274cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner AI->eraseFromParent(); 15284cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner ++NumConverted; 15294cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Changed = true; 15304cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner continue; 15316974302e3ff20746268721959efed807c7711bfcBob Wilson } 15326974302e3ff20746268721959efed807c7711bfcBob Wilson 15334cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Otherwise, couldn't process this alloca. 1534372dda8881c7a32a6f5ce0f76a713e3a9ef46ea1Chris Lattner } 15354cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 15364cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return Changed; 1537372dda8881c7a32a6f5ce0f76a713e3a9ef46ea1Chris Lattner} 1538d2fa781169175b827e50953a1d0b7edc6b0c4801Chris Lattner 15394cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// DoScalarReplacement - This alloca satisfied the isSafeAllocaToScalarRepl 15404cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// predicate, do SROA now. 15416974302e3ff20746268721959efed807c7711bfcBob Wilsonvoid SROA::DoScalarReplacement(AllocaInst *AI, 15424cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner std::vector<AllocaInst*> &WorkList) { 15434cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner DEBUG(dbgs() << "Found inst to SROA: " << *AI << '\n'); 15444cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner SmallVector<AllocaInst*, 32> ElementAllocas; 15454cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (const StructType *ST = dyn_cast<StructType>(AI->getAllocatedType())) { 15464cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner ElementAllocas.reserve(ST->getNumContainedTypes()); 15474cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner for (unsigned i = 0, e = ST->getNumContainedTypes(); i != e; ++i) { 15486974302e3ff20746268721959efed807c7711bfcBob Wilson AllocaInst *NA = new AllocaInst(ST->getContainedType(i), 0, 15494cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner AI->getAlignment(), 15504cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner AI->getName() + "." + Twine(i), AI); 15514cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner ElementAllocas.push_back(NA); 15524cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner WorkList.push_back(NA); // Add to worklist for recursive processing 15534cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 15544cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } else { 15554cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner const ArrayType *AT = cast<ArrayType>(AI->getAllocatedType()); 15564cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner ElementAllocas.reserve(AT->getNumElements()); 15574cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner const Type *ElTy = AT->getElementType(); 15584cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner for (unsigned i = 0, e = AT->getNumElements(); i != e; ++i) { 15594cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner AllocaInst *NA = new AllocaInst(ElTy, 0, AI->getAlignment(), 15604cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner AI->getName() + "." + Twine(i), AI); 15614cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner ElementAllocas.push_back(NA); 15624cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner WorkList.push_back(NA); // Add to worklist for recursive processing 15634cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 15644cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 1565d2fa781169175b827e50953a1d0b7edc6b0c4801Chris Lattner 15664cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Now that we have created the new alloca instructions, rewrite all the 15674cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // uses of the old alloca. 15684cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner RewriteForScalarRepl(AI, AI, 0, ElementAllocas); 1569d2fa781169175b827e50953a1d0b7edc6b0c4801Chris Lattner 15704cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Now erase any instructions that were made dead while rewriting the alloca. 15714cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner DeleteDeadInstructions(); 15724cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner AI->eraseFromParent(); 15734cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 1574fe60104ac97f3a8736dcfbfdf9547c7b7cc7b951Dan Gohman ++NumReplaced; 15754cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner} 15764cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 15774cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// DeleteDeadInstructions - Erase instructions on the DeadInstrs list, 15784cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// recursively including all their operands that become trivially dead. 15794cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattnervoid SROA::DeleteDeadInstructions() { 15804cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner while (!DeadInsts.empty()) { 15814cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Instruction *I = cast<Instruction>(DeadInsts.pop_back_val()); 15824cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 15834cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner for (User::op_iterator OI = I->op_begin(), E = I->op_end(); OI != E; ++OI) 15844cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (Instruction *U = dyn_cast<Instruction>(*OI)) { 15854cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Zero out the operand and see if it becomes trivially dead. 15864cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // (But, don't add allocas to the dead instruction list -- they are 15874cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // already on the worklist and will be deleted separately.) 15884cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner *OI = 0; 15894cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (isInstructionTriviallyDead(U) && !isa<AllocaInst>(U)) 15904cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner DeadInsts.push_back(U); 1591d2fa781169175b827e50953a1d0b7edc6b0c4801Chris Lattner } 1592d2fa781169175b827e50953a1d0b7edc6b0c4801Chris Lattner 15934cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner I->eraseFromParent(); 15944cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 15954cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner} 15966974302e3ff20746268721959efed807c7711bfcBob Wilson 15974cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// isSafeForScalarRepl - Check if instruction I is a safe use with regard to 15984cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// performing scalar replacement of alloca AI. The results are flagged in 15994cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// the Info parameter. Offset indicates the position within AI that is 16004cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// referenced by this instruction. 16016c95d24927b11fb76bc3e76ebe6a8198d74fc178Chris Lattnervoid SROA::isSafeForScalarRepl(Instruction *I, uint64_t Offset, 16024cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner AllocaInfo &Info) { 16034cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner for (Value::use_iterator UI = I->use_begin(), E = I->use_end(); UI!=E; ++UI) { 16044cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Instruction *User = cast<Instruction>(*UI); 16054cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 16064cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (BitCastInst *BC = dyn_cast<BitCastInst>(User)) { 16076c95d24927b11fb76bc3e76ebe6a8198d74fc178Chris Lattner isSafeForScalarRepl(BC, Offset, Info); 16084cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } else if (GetElementPtrInst *GEPI = dyn_cast<GetElementPtrInst>(User)) { 16094cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t GEPOffset = Offset; 16106c95d24927b11fb76bc3e76ebe6a8198d74fc178Chris Lattner isSafeGEP(GEPI, GEPOffset, Info); 16114cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (!Info.isUnsafe) 16126c95d24927b11fb76bc3e76ebe6a8198d74fc178Chris Lattner isSafeForScalarRepl(GEPI, GEPOffset, Info); 161319101c7585c191376d898e3e66e35acd9bd777c2Gabor Greif } else if (MemIntrinsic *MI = dyn_cast<MemIntrinsic>(User)) { 16144cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner ConstantInt *Length = dyn_cast<ConstantInt>(MI->getLength()); 1615d01a0da090407762fe3b770d84f049d72d06467eChris Lattner if (Length == 0) 1616d01a0da090407762fe3b770d84f049d72d06467eChris Lattner return MarkUnsafe(Info, User); 16176c95d24927b11fb76bc3e76ebe6a8198d74fc178Chris Lattner isSafeMemAccess(Offset, Length->getZExtValue(), 0, 1618145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner UI.getOperandNo() == 0, Info, MI, 1619145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner true /*AllowWholeAccess*/); 16204cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } else if (LoadInst *LI = dyn_cast<LoadInst>(User)) { 1621d01a0da090407762fe3b770d84f049d72d06467eChris Lattner if (LI->isVolatile()) 1622d01a0da090407762fe3b770d84f049d72d06467eChris Lattner return MarkUnsafe(Info, User); 1623d01a0da090407762fe3b770d84f049d72d06467eChris Lattner const Type *LIType = LI->getType(); 16246c95d24927b11fb76bc3e76ebe6a8198d74fc178Chris Lattner isSafeMemAccess(Offset, TD->getTypeAllocSize(LIType), 1625145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner LIType, false, Info, LI, true /*AllowWholeAccess*/); 1626d01a0da090407762fe3b770d84f049d72d06467eChris Lattner Info.hasALoadOrStore = true; 1627d01a0da090407762fe3b770d84f049d72d06467eChris Lattner 16284cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } else if (StoreInst *SI = dyn_cast<StoreInst>(User)) { 16294cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Store is ok if storing INTO the pointer, not storing the pointer 1630d01a0da090407762fe3b770d84f049d72d06467eChris Lattner if (SI->isVolatile() || SI->getOperand(0) == I) 1631d01a0da090407762fe3b770d84f049d72d06467eChris Lattner return MarkUnsafe(Info, User); 1632d01a0da090407762fe3b770d84f049d72d06467eChris Lattner 1633d01a0da090407762fe3b770d84f049d72d06467eChris Lattner const Type *SIType = SI->getOperand(0)->getType(); 16346c95d24927b11fb76bc3e76ebe6a8198d74fc178Chris Lattner isSafeMemAccess(Offset, TD->getTypeAllocSize(SIType), 1635145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner SIType, true, Info, SI, true /*AllowWholeAccess*/); 1636145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner Info.hasALoadOrStore = true; 1637145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner } else if (isa<PHINode>(User) || isa<SelectInst>(User)) { 1638145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner isSafePHISelectUseForScalarRepl(User, Offset, Info); 1639145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner } else { 1640145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner return MarkUnsafe(Info, User); 1641145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner } 1642145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner if (Info.isUnsafe) return; 1643145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner } 1644145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner} 1645145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner 1646145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner 1647145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner/// isSafePHIUseForScalarRepl - If we see a PHI node or select using a pointer 1648145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner/// derived from the alloca, we can often still split the alloca into elements. 1649145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner/// This is useful if we have a large alloca where one element is phi'd 1650145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner/// together somewhere: we can SRoA and promote all the other elements even if 1651145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner/// we end up not being able to promote this one. 1652145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner/// 1653145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner/// All we require is that the uses of the PHI do not index into other parts of 1654145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner/// the alloca. The most important use case for this is single load and stores 1655145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner/// that are PHI'd together, which can happen due to code sinking. 1656145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattnervoid SROA::isSafePHISelectUseForScalarRepl(Instruction *I, uint64_t Offset, 1657145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner AllocaInfo &Info) { 1658145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner // If we've already checked this PHI, don't do it again. 1659145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner if (PHINode *PN = dyn_cast<PHINode>(I)) 1660145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner if (!Info.CheckedPHIs.insert(PN)) 1661145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner return; 1662145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner 1663145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner for (Value::use_iterator UI = I->use_begin(), E = I->use_end(); UI!=E; ++UI) { 1664145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner Instruction *User = cast<Instruction>(*UI); 1665145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner 1666145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner if (BitCastInst *BC = dyn_cast<BitCastInst>(User)) { 1667145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner isSafePHISelectUseForScalarRepl(BC, Offset, Info); 1668145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner } else if (GetElementPtrInst *GEPI = dyn_cast<GetElementPtrInst>(User)) { 1669145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner // Only allow "bitcast" GEPs for simplicity. We could generalize this, 1670145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner // but would have to prove that we're staying inside of an element being 1671145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner // promoted. 1672145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner if (!GEPI->hasAllZeroIndices()) 1673145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner return MarkUnsafe(Info, User); 1674145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner isSafePHISelectUseForScalarRepl(GEPI, Offset, Info); 1675145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner } else if (LoadInst *LI = dyn_cast<LoadInst>(User)) { 1676145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner if (LI->isVolatile()) 1677145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner return MarkUnsafe(Info, User); 1678145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner const Type *LIType = LI->getType(); 1679145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner isSafeMemAccess(Offset, TD->getTypeAllocSize(LIType), 1680145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner LIType, false, Info, LI, false /*AllowWholeAccess*/); 1681145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner Info.hasALoadOrStore = true; 1682145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner 1683145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner } else if (StoreInst *SI = dyn_cast<StoreInst>(User)) { 1684145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner // Store is ok if storing INTO the pointer, not storing the pointer 1685145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner if (SI->isVolatile() || SI->getOperand(0) == I) 1686145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner return MarkUnsafe(Info, User); 1687145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner 1688145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner const Type *SIType = SI->getOperand(0)->getType(); 1689145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner isSafeMemAccess(Offset, TD->getTypeAllocSize(SIType), 1690145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner SIType, true, Info, SI, false /*AllowWholeAccess*/); 1691d01a0da090407762fe3b770d84f049d72d06467eChris Lattner Info.hasALoadOrStore = true; 1692145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner } else if (isa<PHINode>(User) || isa<SelectInst>(User)) { 1693145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner isSafePHISelectUseForScalarRepl(User, Offset, Info); 16944cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } else { 1695d01a0da090407762fe3b770d84f049d72d06467eChris Lattner return MarkUnsafe(Info, User); 1696d2fa781169175b827e50953a1d0b7edc6b0c4801Chris Lattner } 16974cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (Info.isUnsafe) return; 1698d2fa781169175b827e50953a1d0b7edc6b0c4801Chris Lattner } 1699d2fa781169175b827e50953a1d0b7edc6b0c4801Chris Lattner} 1700d2fa781169175b827e50953a1d0b7edc6b0c4801Chris Lattner 17014cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// isSafeGEP - Check if a GEP instruction can be handled for scalar 17024cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// replacement. It is safe when all the indices are constant, in-bounds 17034cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// references, and when the resulting offset corresponds to an element within 17044cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// the alloca type. The results are flagged in the Info parameter. Upon 17054cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// return, Offset is adjusted as specified by the GEP indices. 17066c95d24927b11fb76bc3e76ebe6a8198d74fc178Chris Lattnervoid SROA::isSafeGEP(GetElementPtrInst *GEPI, 17074cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t &Offset, AllocaInfo &Info) { 17084cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner gep_type_iterator GEPIt = gep_type_begin(GEPI), E = gep_type_end(GEPI); 17094cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (GEPIt == E) 17104cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return; 17115ffe6acd577696a41932c7b82db06a04687e07baChris Lattner 17124cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Walk through the GEP type indices, checking the types that this indexes 17134cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // into. 17144cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner for (; GEPIt != E; ++GEPIt) { 17154cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Ignore struct elements, no extra checking needed for these. 17164cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if ((*GEPIt)->isStructTy()) 17174cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner continue; 17185ffe6acd577696a41932c7b82db06a04687e07baChris Lattner 17194cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner ConstantInt *IdxVal = dyn_cast<ConstantInt>(GEPIt.getOperand()); 17204cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (!IdxVal) 1721d01a0da090407762fe3b770d84f049d72d06467eChris Lattner return MarkUnsafe(Info, GEPI); 17225ffe6acd577696a41932c7b82db06a04687e07baChris Lattner } 172341b33f437f70dcf63e35d08e5f4202258ef05c15Eli Friedman 17244cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Compute the offset due to this GEP and check if the alloca has a 17254cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // component element at that offset. 17264cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner SmallVector<Value*, 8> Indices(GEPI->op_begin() + 1, GEPI->op_end()); 17274cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Offset += TD->getIndexedOffset(GEPI->getPointerOperandType(), 17284cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner &Indices[0], Indices.size()); 17296c95d24927b11fb76bc3e76ebe6a8198d74fc178Chris Lattner if (!TypeHasComponent(Info.AI->getAllocatedType(), Offset, 0)) 1730d01a0da090407762fe3b770d84f049d72d06467eChris Lattner MarkUnsafe(Info, GEPI); 17314cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner} 173241b33f437f70dcf63e35d08e5f4202258ef05c15Eli Friedman 1733704d1347c5009f674408fae6f78343b415891274Bob Wilson/// isHomogeneousAggregate - Check if type T is a struct or array containing 1734704d1347c5009f674408fae6f78343b415891274Bob Wilson/// elements of the same type (which is always true for arrays). If so, 1735704d1347c5009f674408fae6f78343b415891274Bob Wilson/// return true with NumElts and EltTy set to the number of elements and the 1736704d1347c5009f674408fae6f78343b415891274Bob Wilson/// element type, respectively. 1737704d1347c5009f674408fae6f78343b415891274Bob Wilsonstatic bool isHomogeneousAggregate(const Type *T, unsigned &NumElts, 1738704d1347c5009f674408fae6f78343b415891274Bob Wilson const Type *&EltTy) { 1739704d1347c5009f674408fae6f78343b415891274Bob Wilson if (const ArrayType *AT = dyn_cast<ArrayType>(T)) { 1740704d1347c5009f674408fae6f78343b415891274Bob Wilson NumElts = AT->getNumElements(); 1741f0908aeade2f41d2fed82de8d85448358b379328Bob Wilson EltTy = (NumElts == 0 ? 0 : AT->getElementType()); 1742704d1347c5009f674408fae6f78343b415891274Bob Wilson return true; 1743704d1347c5009f674408fae6f78343b415891274Bob Wilson } 1744704d1347c5009f674408fae6f78343b415891274Bob Wilson if (const StructType *ST = dyn_cast<StructType>(T)) { 1745704d1347c5009f674408fae6f78343b415891274Bob Wilson NumElts = ST->getNumContainedTypes(); 1746f0908aeade2f41d2fed82de8d85448358b379328Bob Wilson EltTy = (NumElts == 0 ? 0 : ST->getContainedType(0)); 1747704d1347c5009f674408fae6f78343b415891274Bob Wilson for (unsigned n = 1; n < NumElts; ++n) { 1748704d1347c5009f674408fae6f78343b415891274Bob Wilson if (ST->getContainedType(n) != EltTy) 1749704d1347c5009f674408fae6f78343b415891274Bob Wilson return false; 1750704d1347c5009f674408fae6f78343b415891274Bob Wilson } 1751704d1347c5009f674408fae6f78343b415891274Bob Wilson return true; 1752704d1347c5009f674408fae6f78343b415891274Bob Wilson } 1753704d1347c5009f674408fae6f78343b415891274Bob Wilson return false; 1754704d1347c5009f674408fae6f78343b415891274Bob Wilson} 1755704d1347c5009f674408fae6f78343b415891274Bob Wilson 1756704d1347c5009f674408fae6f78343b415891274Bob Wilson/// isCompatibleAggregate - Check if T1 and T2 are either the same type or are 1757704d1347c5009f674408fae6f78343b415891274Bob Wilson/// "homogeneous" aggregates with the same element type and number of elements. 1758704d1347c5009f674408fae6f78343b415891274Bob Wilsonstatic bool isCompatibleAggregate(const Type *T1, const Type *T2) { 1759704d1347c5009f674408fae6f78343b415891274Bob Wilson if (T1 == T2) 1760704d1347c5009f674408fae6f78343b415891274Bob Wilson return true; 1761704d1347c5009f674408fae6f78343b415891274Bob Wilson 1762704d1347c5009f674408fae6f78343b415891274Bob Wilson unsigned NumElts1, NumElts2; 1763704d1347c5009f674408fae6f78343b415891274Bob Wilson const Type *EltTy1, *EltTy2; 1764704d1347c5009f674408fae6f78343b415891274Bob Wilson if (isHomogeneousAggregate(T1, NumElts1, EltTy1) && 1765704d1347c5009f674408fae6f78343b415891274Bob Wilson isHomogeneousAggregate(T2, NumElts2, EltTy2) && 1766704d1347c5009f674408fae6f78343b415891274Bob Wilson NumElts1 == NumElts2 && 1767704d1347c5009f674408fae6f78343b415891274Bob Wilson EltTy1 == EltTy2) 1768704d1347c5009f674408fae6f78343b415891274Bob Wilson return true; 1769704d1347c5009f674408fae6f78343b415891274Bob Wilson 1770704d1347c5009f674408fae6f78343b415891274Bob Wilson return false; 1771704d1347c5009f674408fae6f78343b415891274Bob Wilson} 1772704d1347c5009f674408fae6f78343b415891274Bob Wilson 17734cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// isSafeMemAccess - Check if a load/store/memcpy operates on the entire AI 17744cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// alloca or has an offset and size that corresponds to a component element 17754cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// within it. The offset checked here may have been formed from a GEP with a 17764cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// pointer bitcasted to a different type. 1777145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner/// 1778145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner/// If AllowWholeAccess is true, then this allows uses of the entire alloca as a 1779145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner/// unit. If false, it only allows accesses known to be in a single element. 17806c95d24927b11fb76bc3e76ebe6a8198d74fc178Chris Lattnervoid SROA::isSafeMemAccess(uint64_t Offset, uint64_t MemSize, 17814cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner const Type *MemOpType, bool isStore, 1782145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner AllocaInfo &Info, Instruction *TheAccess, 1783145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner bool AllowWholeAccess) { 17844cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Check if this is a load/store of the entire alloca. 1785145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner if (Offset == 0 && AllowWholeAccess && 17866c95d24927b11fb76bc3e76ebe6a8198d74fc178Chris Lattner MemSize == TD->getTypeAllocSize(Info.AI->getAllocatedType())) { 1787704d1347c5009f674408fae6f78343b415891274Bob Wilson // This can be safe for MemIntrinsics (where MemOpType is 0) and integer 1788704d1347c5009f674408fae6f78343b415891274Bob Wilson // loads/stores (which are essentially the same as the MemIntrinsics with 1789704d1347c5009f674408fae6f78343b415891274Bob Wilson // regard to copying padding between elements). But, if an alloca is 1790704d1347c5009f674408fae6f78343b415891274Bob Wilson // flagged as both a source and destination of such operations, we'll need 1791704d1347c5009f674408fae6f78343b415891274Bob Wilson // to check later for padding between elements. 1792704d1347c5009f674408fae6f78343b415891274Bob Wilson if (!MemOpType || MemOpType->isIntegerTy()) { 1793704d1347c5009f674408fae6f78343b415891274Bob Wilson if (isStore) 1794704d1347c5009f674408fae6f78343b415891274Bob Wilson Info.isMemCpyDst = true; 1795704d1347c5009f674408fae6f78343b415891274Bob Wilson else 1796704d1347c5009f674408fae6f78343b415891274Bob Wilson Info.isMemCpySrc = true; 17974cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return; 17984cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 1799704d1347c5009f674408fae6f78343b415891274Bob Wilson // This is also safe for references using a type that is compatible with 1800704d1347c5009f674408fae6f78343b415891274Bob Wilson // the type of the alloca, so that loads/stores can be rewritten using 1801704d1347c5009f674408fae6f78343b415891274Bob Wilson // insertvalue/extractvalue. 18026c95d24927b11fb76bc3e76ebe6a8198d74fc178Chris Lattner if (isCompatibleAggregate(MemOpType, Info.AI->getAllocatedType())) { 18037e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner Info.hasSubelementAccess = true; 1804704d1347c5009f674408fae6f78343b415891274Bob Wilson return; 18057e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner } 18064cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 18074cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Check if the offset/size correspond to a component within the alloca type. 18086c95d24927b11fb76bc3e76ebe6a8198d74fc178Chris Lattner const Type *T = Info.AI->getAllocatedType(); 18097e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner if (TypeHasComponent(T, Offset, MemSize)) { 18107e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner Info.hasSubelementAccess = true; 18114cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return; 18127e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner } 18134cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 1814d01a0da090407762fe3b770d84f049d72d06467eChris Lattner return MarkUnsafe(Info, TheAccess); 18155ffe6acd577696a41932c7b82db06a04687e07baChris Lattner} 18165ffe6acd577696a41932c7b82db06a04687e07baChris Lattner 18174cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// TypeHasComponent - Return true if T has a component type with the 18184cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// specified offset and size. If Size is zero, do not check the size. 18194cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattnerbool SROA::TypeHasComponent(const Type *T, uint64_t Offset, uint64_t Size) { 18204cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner const Type *EltTy; 18214cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t EltSize; 18224cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (const StructType *ST = dyn_cast<StructType>(T)) { 18234cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner const StructLayout *Layout = TD->getStructLayout(ST); 18244cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner unsigned EltIdx = Layout->getElementContainingOffset(Offset); 18254cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner EltTy = ST->getContainedType(EltIdx); 18264cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner EltSize = TD->getTypeAllocSize(EltTy); 18274cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Offset -= Layout->getElementOffset(EltIdx); 18284cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } else if (const ArrayType *AT = dyn_cast<ArrayType>(T)) { 18294cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner EltTy = AT->getElementType(); 18304cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner EltSize = TD->getTypeAllocSize(EltTy); 18314cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (Offset >= AT->getNumElements() * EltSize) 18324cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return false; 18334cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Offset %= EltSize; 18344cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } else { 18354cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return false; 18364cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 18374cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (Offset == 0 && (Size == 0 || EltSize == Size)) 18384cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return true; 18394cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Check if the component spans multiple elements. 18404cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (Offset + Size > EltSize) 18414cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return false; 18424cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return TypeHasComponent(EltTy, Offset, Size); 18434cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner} 18443cb3650a278e37aa6378127c51e407d2823139b4Duncan Sands 18454cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// RewriteForScalarRepl - Alloca AI is being split into NewElts, so rewrite 18464cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// the instruction I, which references it, to use the separate elements. 18474cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// Offset indicates the position within AI that is referenced by this 18484cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// instruction. 18494cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattnervoid SROA::RewriteForScalarRepl(Instruction *I, AllocaInst *AI, uint64_t Offset, 18504cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner SmallVector<AllocaInst*, 32> &NewElts) { 1851145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner for (Value::use_iterator UI = I->use_begin(), E = I->use_end(); UI!=E;) { 1852145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner Use &TheUse = UI.getUse(); 1853145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner Instruction *User = cast<Instruction>(*UI++); 18543cb3650a278e37aa6378127c51e407d2823139b4Duncan Sands 18554cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (BitCastInst *BC = dyn_cast<BitCastInst>(User)) { 18564cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner RewriteBitCast(BC, AI, Offset, NewElts); 1857145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner continue; 1858145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner } 1859145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner 1860145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner if (GetElementPtrInst *GEPI = dyn_cast<GetElementPtrInst>(User)) { 18614cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner RewriteGEP(GEPI, AI, Offset, NewElts); 1862145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner continue; 1863145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner } 1864145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner 1865145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner if (MemIntrinsic *MI = dyn_cast<MemIntrinsic>(User)) { 18664cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner ConstantInt *Length = dyn_cast<ConstantInt>(MI->getLength()); 18674cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t MemSize = Length->getZExtValue(); 18684cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (Offset == 0 && 18694cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner MemSize == TD->getTypeAllocSize(AI->getAllocatedType())) 18704cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner RewriteMemIntrinUserOfAlloca(MI, I, AI, NewElts); 18714cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Otherwise the intrinsic can only touch a single element and the 18724cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // address operand will be updated, so nothing else needs to be done. 1873145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner continue; 1874145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner } 1875145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner 1876145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner if (LoadInst *LI = dyn_cast<LoadInst>(User)) { 18774cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner const Type *LIType = LI->getType(); 1878192228edb1c08ca11da2df959072bcaa99eacd63Chris Lattner 1879704d1347c5009f674408fae6f78343b415891274Bob Wilson if (isCompatibleAggregate(LIType, AI->getAllocatedType())) { 18804cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Replace: 18814cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // %res = load { i32, i32 }* %alloc 18824cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // with: 18834cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // %load.0 = load i32* %alloc.0 18844cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // %insert.0 insertvalue { i32, i32 } zeroinitializer, i32 %load.0, 0 18854cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // %load.1 = load i32* %alloc.1 18864cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // %insert = insertvalue { i32, i32 } %insert.0, i32 %load.1, 1 18874cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // (Also works for arrays instead of structs) 18884cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *Insert = UndefValue::get(LIType); 1889abb25122050349ccf77f8afb198a985e7a4d95eeDevang Patel IRBuilder<> Builder(LI); 18904cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner for (unsigned i = 0, e = NewElts.size(); i != e; ++i) { 1891abb25122050349ccf77f8afb198a985e7a4d95eeDevang Patel Value *Load = Builder.CreateLoad(NewElts[i], "load"); 1892abb25122050349ccf77f8afb198a985e7a4d95eeDevang Patel Insert = Builder.CreateInsertValue(Insert, Load, i, "insert"); 18934cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 18944cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner LI->replaceAllUsesWith(Insert); 18954cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner DeadInsts.push_back(LI); 18964cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } else if (LIType->isIntegerTy() && 18974cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner TD->getTypeAllocSize(LIType) == 18984cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner TD->getTypeAllocSize(AI->getAllocatedType())) { 18994cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If this is a load of the entire alloca to an integer, rewrite it. 19004cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner RewriteLoadUserOfWholeAlloca(LI, AI, NewElts); 19014cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 1902145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner continue; 1903145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner } 1904145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner 1905145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner if (StoreInst *SI = dyn_cast<StoreInst>(User)) { 19064cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *Val = SI->getOperand(0); 19074cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner const Type *SIType = Val->getType(); 1908704d1347c5009f674408fae6f78343b415891274Bob Wilson if (isCompatibleAggregate(SIType, AI->getAllocatedType())) { 19094cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Replace: 19104cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // store { i32, i32 } %val, { i32, i32 }* %alloc 19114cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // with: 19124cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // %val.0 = extractvalue { i32, i32 } %val, 0 19134cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // store i32 %val.0, i32* %alloc.0 19144cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // %val.1 = extractvalue { i32, i32 } %val, 1 19154cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // store i32 %val.1, i32* %alloc.1 19164cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // (Also works for arrays instead of structs) 1917abb25122050349ccf77f8afb198a985e7a4d95eeDevang Patel IRBuilder<> Builder(SI); 19184cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner for (unsigned i = 0, e = NewElts.size(); i != e; ++i) { 1919abb25122050349ccf77f8afb198a985e7a4d95eeDevang Patel Value *Extract = Builder.CreateExtractValue(Val, i, Val->getName()); 1920abb25122050349ccf77f8afb198a985e7a4d95eeDevang Patel Builder.CreateStore(Extract, NewElts[i]); 19214cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 19224cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner DeadInsts.push_back(SI); 19234cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } else if (SIType->isIntegerTy() && 19244cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner TD->getTypeAllocSize(SIType) == 19254cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner TD->getTypeAllocSize(AI->getAllocatedType())) { 19264cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If this is a store of the entire alloca from an integer, rewrite it. 19274cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner RewriteStoreUserOfWholeAlloca(SI, AI, NewElts); 192839a1c04323a5993d6b2993e615ec44c16e19aeeaChris Lattner } 1929145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner continue; 1930145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner } 1931145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner 1932145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner if (isa<SelectInst>(User) || isa<PHINode>(User)) { 1933145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner // If we have a PHI user of the alloca itself (as opposed to a GEP or 1934145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner // bitcast) we have to rewrite it. GEP and bitcast uses will be RAUW'd to 1935145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner // the new pointer. 1936145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner if (!isa<AllocaInst>(I)) continue; 1937145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner 1938145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner assert(Offset == 0 && NewElts[0] && 1939145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner "Direct alloca use should have a zero offset"); 1940145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner 1941145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner // If we have a use of the alloca, we know the derived uses will be 1942145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner // utilizing just the first element of the scalarized result. Insert a 1943145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner // bitcast of the first alloca before the user as required. 1944145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner AllocaInst *NewAI = NewElts[0]; 1945145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner BitCastInst *BCI = new BitCastInst(NewAI, AI->getType(), "", NewAI); 1946145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner NewAI->moveBefore(BCI); 1947145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner TheUse = BCI; 1948145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner continue; 194939a1c04323a5993d6b2993e615ec44c16e19aeeaChris Lattner } 19504cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 19514cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner} 19523cb3650a278e37aa6378127c51e407d2823139b4Duncan Sands 19534cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// RewriteBitCast - Update a bitcast reference to the alloca being replaced 19544cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// and recursively continue updating all of its uses. 19554cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattnervoid SROA::RewriteBitCast(BitCastInst *BC, AllocaInst *AI, uint64_t Offset, 19564cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner SmallVector<AllocaInst*, 32> &NewElts) { 19574cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner RewriteForScalarRepl(BC, AI, Offset, NewElts); 19584cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (BC->getOperand(0) != AI) 19594cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return; 196039a1c04323a5993d6b2993e615ec44c16e19aeeaChris Lattner 19614cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // The bitcast references the original alloca. Replace its uses with 19624cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // references to the first new element alloca. 19634cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Instruction *Val = NewElts[0]; 19644cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (Val->getType() != BC->getDestTy()) { 19654cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Val = new BitCastInst(Val, BC->getDestTy(), "", BC); 19664cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Val->takeName(BC); 196739a1c04323a5993d6b2993e615ec44c16e19aeeaChris Lattner } 19684cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner BC->replaceAllUsesWith(Val); 19694cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner DeadInsts.push_back(BC); 197039a1c04323a5993d6b2993e615ec44c16e19aeeaChris Lattner} 1971372dda8881c7a32a6f5ce0f76a713e3a9ef46ea1Chris Lattner 19724cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// FindElementAndOffset - Return the index of the element containing Offset 19734cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// within the specified type, which must be either a struct or an array. 19744cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// Sets T to the type of the element and Offset to the offset within that 19754cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// element. IdxTy is set to the type of the index result to be used in a 19764cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// GEP instruction. 19774cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattneruint64_t SROA::FindElementAndOffset(const Type *&T, uint64_t &Offset, 19784cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner const Type *&IdxTy) { 19794cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t Idx = 0; 19804cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (const StructType *ST = dyn_cast<StructType>(T)) { 19814cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner const StructLayout *Layout = TD->getStructLayout(ST); 19824cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Idx = Layout->getElementContainingOffset(Offset); 19834cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner T = ST->getContainedType(Idx); 19844cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Offset -= Layout->getElementOffset(Idx); 19854cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner IdxTy = Type::getInt32Ty(T->getContext()); 19864cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return Idx; 1987f5990edc877c4e63503c589928a00ec6ec751830Chris Lattner } 19884cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner const ArrayType *AT = cast<ArrayType>(T); 19894cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner T = AT->getElementType(); 19904cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t EltSize = TD->getTypeAllocSize(T); 19914cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Idx = Offset / EltSize; 19924cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Offset -= Idx * EltSize; 19934cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner IdxTy = Type::getInt64Ty(T->getContext()); 19944cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return Idx; 19955e062a1eda2c4adffd428a35e737a431fc37f4e0Chris Lattner} 1996a188894d67a3cc2516b25aae9b3cbdbff4b0babeChris Lattner 19974cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// RewriteGEP - Check if this GEP instruction moves the pointer across 19984cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// elements of the alloca that are being split apart, and if so, rewrite 19994cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// the GEP to be relative to the new element. 20004cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattnervoid SROA::RewriteGEP(GetElementPtrInst *GEPI, AllocaInst *AI, uint64_t Offset, 20014cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner SmallVector<AllocaInst*, 32> &NewElts) { 20024cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t OldOffset = Offset; 20034cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner SmallVector<Value*, 8> Indices(GEPI->op_begin() + 1, GEPI->op_end()); 20044cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Offset += TD->getIndexedOffset(GEPI->getPointerOperandType(), 20054cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner &Indices[0], Indices.size()); 20064cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 20074cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner RewriteForScalarRepl(GEPI, AI, Offset, NewElts); 20084cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 20094cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner const Type *T = AI->getAllocatedType(); 20104cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner const Type *IdxTy; 20114cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t OldIdx = FindElementAndOffset(T, OldOffset, IdxTy); 20124cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (GEPI->getOperand(0) == AI) 20134cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner OldIdx = ~0ULL; // Force the GEP to be rewritten. 20144cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 20154cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner T = AI->getAllocatedType(); 20164cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t EltOffset = Offset; 20174cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t Idx = FindElementAndOffset(T, EltOffset, IdxTy); 20184cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 20194cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If this GEP does not move the pointer across elements of the alloca 20204cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // being split, then it does not needs to be rewritten. 20214cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (Idx == OldIdx) 2022c4472072641f702dbd99ae12b7da089e75c44a99Chris Lattner return; 2023c4472072641f702dbd99ae12b7da089e75c44a99Chris Lattner 20244cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner const Type *i32Ty = Type::getInt32Ty(AI->getContext()); 20254cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner SmallVector<Value*, 8> NewArgs; 20264cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner NewArgs.push_back(Constant::getNullValue(i32Ty)); 20274cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner while (EltOffset != 0) { 20284cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t EltIdx = FindElementAndOffset(T, EltOffset, IdxTy); 20294cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner NewArgs.push_back(ConstantInt::get(IdxTy, EltIdx)); 20302e0d5f84325303fa95997cd66485811bd0a6ef70Chris Lattner } 20314cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Instruction *Val = NewElts[Idx]; 20324cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (NewArgs.size() > 1) { 20334cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Val = GetElementPtrInst::CreateInBounds(Val, NewArgs.begin(), 20344cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner NewArgs.end(), "", GEPI); 20354cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Val->takeName(GEPI); 20364cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 20374cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (Val->getType() != GEPI->getType()) 20384cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Val = new BitCastInst(Val, GEPI->getType(), Val->getName(), GEPI); 20394cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner GEPI->replaceAllUsesWith(Val); 20404cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner DeadInsts.push_back(GEPI); 2041a188894d67a3cc2516b25aae9b3cbdbff4b0babeChris Lattner} 2042a188894d67a3cc2516b25aae9b3cbdbff4b0babeChris Lattner 20434cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// RewriteMemIntrinUserOfAlloca - MI is a memcpy/memset/memmove from or to AI. 20444cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// Rewrite it to copy or set the elements of the scalarized memory. 20454cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattnervoid SROA::RewriteMemIntrinUserOfAlloca(MemIntrinsic *MI, Instruction *Inst, 20464cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner AllocaInst *AI, 20474cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner SmallVector<AllocaInst*, 32> &NewElts) { 20484cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If this is a memcpy/memmove, construct the other pointer as the 20494cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // appropriate type. The "Other" pointer is the pointer that goes to memory 20504cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // that doesn't have anything to do with the alloca that we are promoting. For 20514cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // memset, this Value* stays null. 20524cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *OtherPtr = 0; 20534cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner unsigned MemAlignment = MI->getAlignment(); 20544cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (MemTransferInst *MTI = dyn_cast<MemTransferInst>(MI)) { // memmove/memcopy 20554cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (Inst == MTI->getRawDest()) 20564cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner OtherPtr = MTI->getRawSource(); 20574cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner else { 20584cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner assert(Inst == MTI->getRawSource()); 20594cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner OtherPtr = MTI->getRawDest(); 2060a188894d67a3cc2516b25aae9b3cbdbff4b0babeChris Lattner } 20614cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 20623ce5e887aef457701da95f1c6ccbd58ec3d32fe4Chris Lattner 20634cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If there is an other pointer, we want to convert it to the same pointer 20644cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // type as AI has, so we can GEP through it safely. 20654cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (OtherPtr) { 20660238f8c430050d23ef861169bb4c4f930af0ef97Chris Lattner unsigned AddrSpace = 20670238f8c430050d23ef861169bb4c4f930af0ef97Chris Lattner cast<PointerType>(OtherPtr->getType())->getAddressSpace(); 20684cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 20694cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Remove bitcasts and all-zero GEPs from OtherPtr. This is an 20704cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // optimization, but it's also required to detect the corner case where 20714cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // both pointer operands are referencing the same memory, and where 20724cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // OtherPtr may be a bitcast or GEP that currently being rewritten. (This 20734cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // function is only called for mem intrinsics that access the whole 20744cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // aggregate, so non-zero GEPs are not an issue here.) 20750238f8c430050d23ef861169bb4c4f930af0ef97Chris Lattner OtherPtr = OtherPtr->stripPointerCasts(); 20766974302e3ff20746268721959efed807c7711bfcBob Wilson 20774cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Copying the alloca to itself is a no-op: just delete it. 20784cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (OtherPtr == AI || OtherPtr == NewElts[0]) { 20794cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // This code will run twice for a no-op memcpy -- once for each operand. 20804cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Put only one reference to MI on the DeadInsts list. 20814cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner for (SmallVector<Value*, 32>::const_iterator I = DeadInsts.begin(), 20824cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner E = DeadInsts.end(); I != E; ++I) 20834cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (*I == MI) return; 20844cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner DeadInsts.push_back(MI); 20854cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return; 2086c570487d45f7426dc5f75c0309122d6f9330ecf7Chris Lattner } 20876974302e3ff20746268721959efed807c7711bfcBob Wilson 20884cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If the pointer is not the right type, insert a bitcast to the right 20894cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // type. 20900238f8c430050d23ef861169bb4c4f930af0ef97Chris Lattner const Type *NewTy = 20910238f8c430050d23ef861169bb4c4f930af0ef97Chris Lattner PointerType::get(AI->getType()->getElementType(), AddrSpace); 20926974302e3ff20746268721959efed807c7711bfcBob Wilson 20930238f8c430050d23ef861169bb4c4f930af0ef97Chris Lattner if (OtherPtr->getType() != NewTy) 20940238f8c430050d23ef861169bb4c4f930af0ef97Chris Lattner OtherPtr = new BitCastInst(OtherPtr, NewTy, OtherPtr->getName(), MI); 2095a188894d67a3cc2516b25aae9b3cbdbff4b0babeChris Lattner } 20966974302e3ff20746268721959efed807c7711bfcBob Wilson 20974cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Process each element of the aggregate. 20984cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner bool SROADest = MI->getRawDest() == Inst; 20996974302e3ff20746268721959efed807c7711bfcBob Wilson 21004cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Constant *Zero = Constant::getNullValue(Type::getInt32Ty(MI->getContext())); 21014b3dfbd220835cbba519162712c9cb6afaa44059Duncan Sands 21024cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner for (unsigned i = 0, e = NewElts.size(); i != e; ++i) { 21034cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If this is a memcpy/memmove, emit a GEP of the other element address. 21044cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *OtherElt = 0; 21054cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner unsigned OtherEltAlign = MemAlignment; 21066974302e3ff20746268721959efed807c7711bfcBob Wilson 21074cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (OtherPtr) { 21084cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *Idx[2] = { Zero, 21094cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner ConstantInt::get(Type::getInt32Ty(MI->getContext()), i) }; 21104cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner OtherElt = GetElementPtrInst::CreateInBounds(OtherPtr, Idx, Idx + 2, 21114cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner OtherPtr->getName()+"."+Twine(i), 21124cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner MI); 21134cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t EltOffset; 21144cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner const PointerType *OtherPtrTy = cast<PointerType>(OtherPtr->getType()); 2115d55c1c16598eba6111fb3a5b6e5dbc6469a562f7Chris Lattner const Type *OtherTy = OtherPtrTy->getElementType(); 2116d55c1c16598eba6111fb3a5b6e5dbc6469a562f7Chris Lattner if (const StructType *ST = dyn_cast<StructType>(OtherTy)) { 21174cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner EltOffset = TD->getStructLayout(ST)->getElementOffset(i); 21184cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } else { 2119d55c1c16598eba6111fb3a5b6e5dbc6469a562f7Chris Lattner const Type *EltTy = cast<SequentialType>(OtherTy)->getElementType(); 21204cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner EltOffset = TD->getTypeAllocSize(EltTy)*i; 21214cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 21226974302e3ff20746268721959efed807c7711bfcBob Wilson 21234cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // The alignment of the other pointer is the guaranteed alignment of the 21244cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // element, which is affected by both the known alignment of the whole 21254cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // mem intrinsic and the alignment of the element. If the alignment of 21264cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // the memcpy (f.e.) is 32 but the element is at a 4-byte offset, then the 21274cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // known alignment is just 4 bytes. 21284cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner OtherEltAlign = (unsigned)MinAlign(OtherEltAlign, EltOffset); 21299bc67da0a9982f2f7597d1d46cf18f079e4f8f98Chris Lattner } 21306974302e3ff20746268721959efed807c7711bfcBob Wilson 21314cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *EltPtr = NewElts[i]; 21324cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner const Type *EltTy = cast<PointerType>(EltPtr->getType())->getElementType(); 21336974302e3ff20746268721959efed807c7711bfcBob Wilson 21344cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If we got down to a scalar, insert a load or store as appropriate. 21354cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (EltTy->isSingleValueType()) { 21364cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (isa<MemTransferInst>(MI)) { 21374cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (SROADest) { 21384cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // From Other to Alloca. 21394cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *Elt = new LoadInst(OtherElt, "tmp", false, OtherEltAlign, MI); 21404cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner new StoreInst(Elt, EltPtr, MI); 21414cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } else { 21424cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // From Alloca to Other. 21434cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *Elt = new LoadInst(EltPtr, "tmp", MI); 21444cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner new StoreInst(Elt, OtherElt, false, OtherEltAlign, MI); 21454cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 21464cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner continue; 214733e24adc3bc3d046aa05cf903fb74da1610b57cbChris Lattner } 21484cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner assert(isa<MemSetInst>(MI)); 21496974302e3ff20746268721959efed807c7711bfcBob Wilson 21504cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If the stored element is zero (common case), just store a null 21514cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // constant. 21524cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Constant *StoreVal; 21536f14c8c7c1ec97797a04631abad6885bfaabcc6dGabor Greif if (ConstantInt *CI = dyn_cast<ConstantInt>(MI->getArgOperand(1))) { 21544cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (CI->isZero()) { 21554cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner StoreVal = Constant::getNullValue(EltTy); // 0.0, null, 0, <0,0> 21564cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } else { 21574cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If EltTy is a vector type, get the element type. 21584cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner const Type *ValTy = EltTy->getScalarType(); 2159c570487d45f7426dc5f75c0309122d6f9330ecf7Chris Lattner 21604cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Construct an integer with the right value. 21614cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner unsigned EltSize = TD->getTypeSizeInBits(ValTy); 21624cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner APInt OneVal(EltSize, CI->getZExtValue()); 21634cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner APInt TotalVal(OneVal); 21644cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Set each byte. 21654cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner for (unsigned i = 0; 8*i < EltSize; ++i) { 21664cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner TotalVal = TotalVal.shl(8); 21674cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner TotalVal |= OneVal; 21684cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 21696974302e3ff20746268721959efed807c7711bfcBob Wilson 21704cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Convert the integer value to the appropriate type. 2171d55c1c16598eba6111fb3a5b6e5dbc6469a562f7Chris Lattner StoreVal = ConstantInt::get(CI->getContext(), TotalVal); 21724cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (ValTy->isPointerTy()) 21734cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner StoreVal = ConstantExpr::getIntToPtr(StoreVal, ValTy); 21744cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner else if (ValTy->isFloatingPointTy()) 21754cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner StoreVal = ConstantExpr::getBitCast(StoreVal, ValTy); 21764cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner assert(StoreVal->getType() == ValTy && "Type mismatch!"); 21776974302e3ff20746268721959efed807c7711bfcBob Wilson 21784cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If the requested value was a vector constant, create it. 21794cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (EltTy != ValTy) { 21804cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner unsigned NumElts = cast<VectorType>(ValTy)->getNumElements(); 21814cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner SmallVector<Constant*, 16> Elts(NumElts, StoreVal); 21822ca5c8644e6c35b3a7910a576ed89cddb7b82c3bChris Lattner StoreVal = ConstantVector::get(Elts); 21834cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 21844cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 21854cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner new StoreInst(StoreVal, EltPtr, MI); 21864cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner continue; 21874cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 21884cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Otherwise, if we're storing a byte variable, use a memset call for 21894cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // this element. 21904cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 21916974302e3ff20746268721959efed807c7711bfcBob Wilson 21924cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner unsigned EltSize = TD->getTypeAllocSize(EltTy); 21936974302e3ff20746268721959efed807c7711bfcBob Wilson 219461db1f56d0b717d67557bbb2a9d83af1449458cbChris Lattner IRBuilder<> Builder(MI); 21956974302e3ff20746268721959efed807c7711bfcBob Wilson 21964cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Finally, insert the meminst for this element. 219761db1f56d0b717d67557bbb2a9d83af1449458cbChris Lattner if (isa<MemSetInst>(MI)) { 219861db1f56d0b717d67557bbb2a9d83af1449458cbChris Lattner Builder.CreateMemSet(EltPtr, MI->getArgOperand(1), EltSize, 219961db1f56d0b717d67557bbb2a9d83af1449458cbChris Lattner MI->isVolatile()); 22004cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } else { 220161db1f56d0b717d67557bbb2a9d83af1449458cbChris Lattner assert(isa<MemTransferInst>(MI)); 220261db1f56d0b717d67557bbb2a9d83af1449458cbChris Lattner Value *Dst = SROADest ? EltPtr : OtherElt; // Dest ptr 220361db1f56d0b717d67557bbb2a9d83af1449458cbChris Lattner Value *Src = SROADest ? OtherElt : EltPtr; // Src ptr 22046974302e3ff20746268721959efed807c7711bfcBob Wilson 220561db1f56d0b717d67557bbb2a9d83af1449458cbChris Lattner if (isa<MemCpyInst>(MI)) 220661db1f56d0b717d67557bbb2a9d83af1449458cbChris Lattner Builder.CreateMemCpy(Dst, Src, EltSize, OtherEltAlign,MI->isVolatile()); 220761db1f56d0b717d67557bbb2a9d83af1449458cbChris Lattner else 220861db1f56d0b717d67557bbb2a9d83af1449458cbChris Lattner Builder.CreateMemMove(Dst, Src, EltSize,OtherEltAlign,MI->isVolatile()); 22094cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 2210a188894d67a3cc2516b25aae9b3cbdbff4b0babeChris Lattner } 22114cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner DeadInsts.push_back(MI); 2212a188894d67a3cc2516b25aae9b3cbdbff4b0babeChris Lattner} 221379b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner 22144cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// RewriteStoreUserOfWholeAlloca - We found a store of an integer that 22154cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// overwrites the entire allocation. Extract out the pieces of the stored 22164cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// integer and store them individually. 22174cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattnervoid SROA::RewriteStoreUserOfWholeAlloca(StoreInst *SI, AllocaInst *AI, 22184cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner SmallVector<AllocaInst*, 32> &NewElts){ 22194cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Extract each element out of the integer according to its structure offset 22204cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // and store the element value to the individual alloca. 22214cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *SrcVal = SI->getOperand(0); 22224cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner const Type *AllocaEltTy = AI->getAllocatedType(); 22234cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t AllocaSizeBits = TD->getTypeAllocSizeInBits(AllocaEltTy); 22246974302e3ff20746268721959efed807c7711bfcBob Wilson 222570728532799d751b8e0e97719dcb3344a2fc97deChris Lattner IRBuilder<> Builder(SI); 222670728532799d751b8e0e97719dcb3344a2fc97deChris Lattner 22274cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Handle tail padding by extending the operand 22284cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (TD->getTypeSizeInBits(SrcVal->getType()) != AllocaSizeBits) 222970728532799d751b8e0e97719dcb3344a2fc97deChris Lattner SrcVal = Builder.CreateZExt(SrcVal, 223070728532799d751b8e0e97719dcb3344a2fc97deChris Lattner IntegerType::get(SI->getContext(), AllocaSizeBits)); 22314b3dfbd220835cbba519162712c9cb6afaa44059Duncan Sands 22324cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner DEBUG(dbgs() << "PROMOTING STORE TO WHOLE ALLOCA: " << *AI << '\n' << *SI 22334cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner << '\n'); 22344b3dfbd220835cbba519162712c9cb6afaa44059Duncan Sands 22354cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // There are two forms here: AI could be an array or struct. Both cases 22364cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // have different ways to compute the element offset. 22374cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (const StructType *EltSTy = dyn_cast<StructType>(AllocaEltTy)) { 22384cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner const StructLayout *Layout = TD->getStructLayout(EltSTy); 22396974302e3ff20746268721959efed807c7711bfcBob Wilson 22404cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner for (unsigned i = 0, e = NewElts.size(); i != e; ++i) { 22414cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Get the number of bits to shift SrcVal to get the value. 22424cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner const Type *FieldTy = EltSTy->getElementType(i); 22434cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t Shift = Layout->getElementOffsetInBits(i); 22446974302e3ff20746268721959efed807c7711bfcBob Wilson 22454cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (TD->isBigEndian()) 22464cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Shift = AllocaSizeBits-Shift-TD->getTypeAllocSizeInBits(FieldTy); 22476974302e3ff20746268721959efed807c7711bfcBob Wilson 22484cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *EltVal = SrcVal; 22494cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (Shift) { 22504cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *ShiftVal = ConstantInt::get(EltVal->getType(), Shift); 225170728532799d751b8e0e97719dcb3344a2fc97deChris Lattner EltVal = Builder.CreateLShr(EltVal, ShiftVal, "sroa.store.elt"); 22524cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 22536974302e3ff20746268721959efed807c7711bfcBob Wilson 22544cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Truncate down to an integer of the right size. 22554cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t FieldSizeBits = TD->getTypeSizeInBits(FieldTy); 22566974302e3ff20746268721959efed807c7711bfcBob Wilson 22574cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Ignore zero sized fields like {}, they obviously contain no data. 22584cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (FieldSizeBits == 0) continue; 22596974302e3ff20746268721959efed807c7711bfcBob Wilson 22604cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (FieldSizeBits != AllocaSizeBits) 226170728532799d751b8e0e97719dcb3344a2fc97deChris Lattner EltVal = Builder.CreateTrunc(EltVal, 226270728532799d751b8e0e97719dcb3344a2fc97deChris Lattner IntegerType::get(SI->getContext(), FieldSizeBits)); 22634cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *DestField = NewElts[i]; 22644cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (EltVal->getType() == FieldTy) { 22654cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Storing to an integer field of this size, just do it. 22664cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } else if (FieldTy->isFloatingPointTy() || FieldTy->isVectorTy()) { 22674cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Bitcast to the right element type (for fp/vector values). 226870728532799d751b8e0e97719dcb3344a2fc97deChris Lattner EltVal = Builder.CreateBitCast(EltVal, FieldTy); 22694cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } else { 22704cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Otherwise, bitcast the dest pointer (for aggregates). 227170728532799d751b8e0e97719dcb3344a2fc97deChris Lattner DestField = Builder.CreateBitCast(DestField, 227270728532799d751b8e0e97719dcb3344a2fc97deChris Lattner PointerType::getUnqual(EltVal->getType())); 22734cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 22744cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner new StoreInst(EltVal, DestField, SI); 22754cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 22766974302e3ff20746268721959efed807c7711bfcBob Wilson 22779d34c4d678cfc836a59a114b7b2cf91e9dd5eac4Chris Lattner } else { 22784cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner const ArrayType *ATy = cast<ArrayType>(AllocaEltTy); 22794cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner const Type *ArrayEltTy = ATy->getElementType(); 22804cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t ElementOffset = TD->getTypeAllocSizeInBits(ArrayEltTy); 22814cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t ElementSizeBits = TD->getTypeSizeInBits(ArrayEltTy); 22824b3dfbd220835cbba519162712c9cb6afaa44059Duncan Sands 22834cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t Shift; 22846974302e3ff20746268721959efed807c7711bfcBob Wilson 22854cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (TD->isBigEndian()) 22864cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Shift = AllocaSizeBits-ElementOffset; 22876974302e3ff20746268721959efed807c7711bfcBob Wilson else 22884cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Shift = 0; 22896974302e3ff20746268721959efed807c7711bfcBob Wilson 22904cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner for (unsigned i = 0, e = NewElts.size(); i != e; ++i) { 22914cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Ignore zero sized fields like {}, they obviously contain no data. 22924cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (ElementSizeBits == 0) continue; 22936974302e3ff20746268721959efed807c7711bfcBob Wilson 22944cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *EltVal = SrcVal; 22954cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (Shift) { 22964cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *ShiftVal = ConstantInt::get(EltVal->getType(), Shift); 229770728532799d751b8e0e97719dcb3344a2fc97deChris Lattner EltVal = Builder.CreateLShr(EltVal, ShiftVal, "sroa.store.elt"); 22984cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 22996974302e3ff20746268721959efed807c7711bfcBob Wilson 23004cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Truncate down to an integer of the right size. 23014cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (ElementSizeBits != AllocaSizeBits) 230270728532799d751b8e0e97719dcb3344a2fc97deChris Lattner EltVal = Builder.CreateTrunc(EltVal, 230370728532799d751b8e0e97719dcb3344a2fc97deChris Lattner IntegerType::get(SI->getContext(), 230470728532799d751b8e0e97719dcb3344a2fc97deChris Lattner ElementSizeBits)); 23054cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *DestField = NewElts[i]; 23064cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (EltVal->getType() == ArrayEltTy) { 23074cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Storing to an integer field of this size, just do it. 23084cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } else if (ArrayEltTy->isFloatingPointTy() || 23094cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner ArrayEltTy->isVectorTy()) { 23104cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Bitcast to the right element type (for fp/vector values). 231170728532799d751b8e0e97719dcb3344a2fc97deChris Lattner EltVal = Builder.CreateBitCast(EltVal, ArrayEltTy); 23124cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } else { 23134cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Otherwise, bitcast the dest pointer (for aggregates). 231470728532799d751b8e0e97719dcb3344a2fc97deChris Lattner DestField = Builder.CreateBitCast(DestField, 231570728532799d751b8e0e97719dcb3344a2fc97deChris Lattner PointerType::getUnqual(EltVal->getType())); 23164cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 23174cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner new StoreInst(EltVal, DestField, SI); 23186974302e3ff20746268721959efed807c7711bfcBob Wilson 23194cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (TD->isBigEndian()) 23204cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Shift -= ElementOffset; 23216974302e3ff20746268721959efed807c7711bfcBob Wilson else 23224cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Shift += ElementOffset; 23234cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 2324800de31776356910eb877e71df9f32b0a6215324Chris Lattner } 23256974302e3ff20746268721959efed807c7711bfcBob Wilson 23264cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner DeadInsts.push_back(SI); 2327800de31776356910eb877e71df9f32b0a6215324Chris Lattner} 2328800de31776356910eb877e71df9f32b0a6215324Chris Lattner 23294cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// RewriteLoadUserOfWholeAlloca - We found a load of the entire allocation to 23304cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// an integer. Load the individual pieces to form the aggregate value. 23314cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattnervoid SROA::RewriteLoadUserOfWholeAlloca(LoadInst *LI, AllocaInst *AI, 23324cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner SmallVector<AllocaInst*, 32> &NewElts) { 23334cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Extract each element out of the NewElts according to its structure offset 23344cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // and form the result value. 23354cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner const Type *AllocaEltTy = AI->getAllocatedType(); 23364cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t AllocaSizeBits = TD->getTypeAllocSizeInBits(AllocaEltTy); 23376974302e3ff20746268721959efed807c7711bfcBob Wilson 23384cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner DEBUG(dbgs() << "PROMOTING LOAD OF WHOLE ALLOCA: " << *AI << '\n' << *LI 23394cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner << '\n'); 23406974302e3ff20746268721959efed807c7711bfcBob Wilson 23414cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // There are two forms here: AI could be an array or struct. Both cases 23424cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // have different ways to compute the element offset. 23434cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner const StructLayout *Layout = 0; 23444cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t ArrayEltBitOffset = 0; 23454cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (const StructType *EltSTy = dyn_cast<StructType>(AllocaEltTy)) { 23464cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Layout = TD->getStructLayout(EltSTy); 23474cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } else { 23484cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner const Type *ArrayEltTy = cast<ArrayType>(AllocaEltTy)->getElementType(); 23494cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner ArrayEltBitOffset = TD->getTypeAllocSizeInBits(ArrayEltTy); 23506974302e3ff20746268721959efed807c7711bfcBob Wilson } 23516974302e3ff20746268721959efed807c7711bfcBob Wilson 23526974302e3ff20746268721959efed807c7711bfcBob Wilson Value *ResultVal = 23534cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Constant::getNullValue(IntegerType::get(LI->getContext(), AllocaSizeBits)); 23546974302e3ff20746268721959efed807c7711bfcBob Wilson 23554cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner for (unsigned i = 0, e = NewElts.size(); i != e; ++i) { 23564cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Load the value from the alloca. If the NewElt is an aggregate, cast 23574cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // the pointer to an integer of the same size before doing the load. 23584cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *SrcField = NewElts[i]; 23594cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner const Type *FieldTy = 23604cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner cast<PointerType>(SrcField->getType())->getElementType(); 23614cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t FieldSizeBits = TD->getTypeSizeInBits(FieldTy); 23626974302e3ff20746268721959efed807c7711bfcBob Wilson 23634cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Ignore zero sized fields like {}, they obviously contain no data. 23644cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (FieldSizeBits == 0) continue; 23656974302e3ff20746268721959efed807c7711bfcBob Wilson 23666974302e3ff20746268721959efed807c7711bfcBob Wilson const IntegerType *FieldIntTy = IntegerType::get(LI->getContext(), 23674cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner FieldSizeBits); 23684cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (!FieldTy->isIntegerTy() && !FieldTy->isFloatingPointTy() && 23694cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner !FieldTy->isVectorTy()) 23704cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner SrcField = new BitCastInst(SrcField, 23714cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner PointerType::getUnqual(FieldIntTy), 23724cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner "", LI); 23734cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner SrcField = new LoadInst(SrcField, "sroa.load.elt", LI); 237429e641761e81bd000bdc4ccfae479c6dda18e402Chris Lattner 23754cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If SrcField is a fp or vector of the right size but that isn't an 23764cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // integer type, bitcast to an integer so we can shift it. 23774cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (SrcField->getType() != FieldIntTy) 23784cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner SrcField = new BitCastInst(SrcField, FieldIntTy, "", LI); 237929e641761e81bd000bdc4ccfae479c6dda18e402Chris Lattner 23804cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Zero extend the field to be the same size as the final alloca so that 23814cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // we can shift and insert it. 23824cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (SrcField->getType() != ResultVal->getType()) 23834cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner SrcField = new ZExtInst(SrcField, ResultVal->getType(), "", LI); 23846974302e3ff20746268721959efed807c7711bfcBob Wilson 23854cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Determine the number of bits to shift SrcField. 23864cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t Shift; 23874cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (Layout) // Struct case. 23884cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Shift = Layout->getElementOffsetInBits(i); 23894cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner else // Array case. 23904cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Shift = i*ArrayEltBitOffset; 23916974302e3ff20746268721959efed807c7711bfcBob Wilson 23924cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (TD->isBigEndian()) 23934cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Shift = AllocaSizeBits-Shift-FieldIntTy->getBitWidth(); 23946974302e3ff20746268721959efed807c7711bfcBob Wilson 23954cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (Shift) { 23964cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *ShiftVal = ConstantInt::get(SrcField->getType(), Shift); 23974cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner SrcField = BinaryOperator::CreateShl(SrcField, ShiftVal, "", LI); 23989b872db775797dea4b391a9347cfbd2ca9c558e2Chris Lattner } 23994cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 24001495247f517c0ac3aeeb9e6c7c0205dd7849d332Chris Lattner // Don't create an 'or x, 0' on the first iteration. 24011495247f517c0ac3aeeb9e6c7c0205dd7849d332Chris Lattner if (!isa<Constant>(ResultVal) || 24021495247f517c0ac3aeeb9e6c7c0205dd7849d332Chris Lattner !cast<Constant>(ResultVal)->isNullValue()) 24031495247f517c0ac3aeeb9e6c7c0205dd7849d332Chris Lattner ResultVal = BinaryOperator::CreateOr(SrcField, ResultVal, "", LI); 24041495247f517c0ac3aeeb9e6c7c0205dd7849d332Chris Lattner else 24051495247f517c0ac3aeeb9e6c7c0205dd7849d332Chris Lattner ResultVal = SrcField; 24069b872db775797dea4b391a9347cfbd2ca9c558e2Chris Lattner } 24074b3dfbd220835cbba519162712c9cb6afaa44059Duncan Sands 24084cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Handle tail padding by truncating the result 24094cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (TD->getTypeSizeInBits(LI->getType()) != AllocaSizeBits) 24104cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner ResultVal = new TruncInst(ResultVal, LI->getType(), "", LI); 24114b3dfbd220835cbba519162712c9cb6afaa44059Duncan Sands 24124cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner LI->replaceAllUsesWith(ResultVal); 24134cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner DeadInsts.push_back(LI); 24144cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner} 24154cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 24164cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// HasPadding - Return true if the specified type has any structure or 2417694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson/// alignment padding in between the elements that would be split apart 2418694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson/// by SROA; return false otherwise. 24194cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattnerstatic bool HasPadding(const Type *Ty, const TargetData &TD) { 2420694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson if (const ArrayType *ATy = dyn_cast<ArrayType>(Ty)) { 2421694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson Ty = ATy->getElementType(); 2422694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson return TD.getTypeSizeInBits(Ty) != TD.getTypeAllocSizeInBits(Ty); 2423694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson } 24244cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 2425694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson // SROA currently handles only Arrays and Structs. 2426694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson const StructType *STy = cast<StructType>(Ty); 2427694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson const StructLayout *SL = TD.getStructLayout(STy); 2428694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson unsigned PrevFieldBitOffset = 0; 2429694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson for (unsigned i = 0, e = STy->getNumElements(); i != e; ++i) { 2430694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson unsigned FieldBitOffset = SL->getElementOffsetInBits(i); 2431694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson 2432694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson // Check to see if there is any padding between this element and the 2433694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson // previous one. 2434694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson if (i) { 2435694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson unsigned PrevFieldEnd = 24364cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner PrevFieldBitOffset+TD.getTypeSizeInBits(STy->getElementType(i-1)); 2437694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson if (PrevFieldEnd < FieldBitOffset) 24384cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return true; 24394cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 2440694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson PrevFieldBitOffset = FieldBitOffset; 24412e0d5f84325303fa95997cd66485811bd0a6ef70Chris Lattner } 2442694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson // Check for tail padding. 2443694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson if (unsigned EltCount = STy->getNumElements()) { 2444694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson unsigned PrevFieldEnd = PrevFieldBitOffset + 2445694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson TD.getTypeSizeInBits(STy->getElementType(EltCount-1)); 2446694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson if (PrevFieldEnd < SL->getSizeInBits()) 2447694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson return true; 2448694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson } 2449694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson return false; 24504cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner} 24514b3dfbd220835cbba519162712c9cb6afaa44059Duncan Sands 24524cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// isSafeStructAllocaToScalarRepl - Check to see if the specified allocation of 24534cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// an aggregate can be broken down into elements. Return 0 if not, 3 if safe, 24544cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// or 1 if safe after canonicalization has been performed. 24554cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattnerbool SROA::isSafeAllocaToScalarRepl(AllocaInst *AI) { 24564cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Loop over the use list of the alloca. We can only transform it if all of 24574cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // the users are safe to transform. 24586c95d24927b11fb76bc3e76ebe6a8198d74fc178Chris Lattner AllocaInfo Info(AI); 24596974302e3ff20746268721959efed807c7711bfcBob Wilson 24606c95d24927b11fb76bc3e76ebe6a8198d74fc178Chris Lattner isSafeForScalarRepl(AI, 0, Info); 24614cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (Info.isUnsafe) { 24624cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner DEBUG(dbgs() << "Cannot transform: " << *AI << '\n'); 24634cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return false; 2464800de31776356910eb877e71df9f32b0a6215324Chris Lattner } 24656974302e3ff20746268721959efed807c7711bfcBob Wilson 24664cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Okay, we know all the users are promotable. If the aggregate is a memcpy 24674cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // source and destination, we have to be careful. In particular, the memcpy 24684cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // could be moving around elements that live in structure padding of the LLVM 24694cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // types, but may actually be used. In these cases, we refuse to promote the 24704cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // struct. 24714cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (Info.isMemCpySrc && Info.isMemCpyDst && 24724cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner HasPadding(AI->getAllocatedType(), *TD)) 24734cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return false; 24744cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 2475396a0567cf959d86a8a1ad185e54d84f5dacbacfChris Lattner // If the alloca never has an access to just *part* of it, but is accessed 2476396a0567cf959d86a8a1ad185e54d84f5dacbacfChris Lattner // via loads and stores, then we should use ConvertToScalarInfo to promote 24777e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner // the alloca instead of promoting each piece at a time and inserting fission 24787e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner // and fusion code. 24797e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner if (!Info.hasSubelementAccess && Info.hasALoadOrStore) { 24807e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner // If the struct/array just has one element, use basic SRoA. 24817e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner if (const StructType *ST = dyn_cast<StructType>(AI->getAllocatedType())) { 24827e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner if (ST->getNumElements() > 1) return false; 24837e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner } else { 24847e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner if (cast<ArrayType>(AI->getAllocatedType())->getNumElements() > 1) 24857e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner return false; 24867e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner } 24877e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner } 2488145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner 24894cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return true; 2490800de31776356910eb877e71df9f32b0a6215324Chris Lattner} 2491800de31776356910eb877e71df9f32b0a6215324Chris Lattner 2492800de31776356910eb877e71df9f32b0a6215324Chris Lattner 249379b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner 249479b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner/// PointsToConstantGlobal - Return true if V (possibly indirectly) points to 249579b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner/// some part of a constant global variable. This intentionally only accepts 249679b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner/// constant expressions because we don't can't rewrite arbitrary instructions. 249779b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattnerstatic bool PointsToConstantGlobal(Value *V) { 249879b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner if (GlobalVariable *GV = dyn_cast<GlobalVariable>(V)) 249979b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner return GV->isConstant(); 250079b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner if (ConstantExpr *CE = dyn_cast<ConstantExpr>(V)) 25016974302e3ff20746268721959efed807c7711bfcBob Wilson if (CE->getOpcode() == Instruction::BitCast || 250279b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner CE->getOpcode() == Instruction::GetElementPtr) 250379b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner return PointsToConstantGlobal(CE->getOperand(0)); 250479b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner return false; 250579b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner} 250679b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner 250779b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner/// isOnlyCopiedFromConstantGlobal - Recursively walk the uses of a (derived) 250879b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner/// pointer to an alloca. Ignore any reads of the pointer, return false if we 250979b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner/// see any stores or other unknown uses. If we see pointer arithmetic, keep 251079b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner/// track of whether it moves the pointer (with isOffset) but otherwise traverse 251179b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner/// the uses. If we see a memcpy/memmove that targets an unoffseted pointer to 2512081f80078dccf02c1f9c61378ff88bbf1b4afb5eNick Lewycky/// the alloca, and if the source pointer is a pointer to a constant global, we 251379b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner/// can optimize this. 25149174d5c7383490d79b6a483d73cded54e32275d6Nick Lewyckystatic bool 25159174d5c7383490d79b6a483d73cded54e32275d6Nick LewyckyisOnlyCopiedFromConstantGlobal(Value *V, MemTransferInst *&TheCopy, 25169174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky bool isOffset, 25179174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky SmallVector<Instruction *, 4> &LifetimeMarkers) { 25189174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky // We track lifetime intrinsics as we encounter them. If we decide to go 25199174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky // ahead and replace the value with the global, this lets the caller quickly 25209174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky // eliminate the markers. 25219174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky 252279b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner for (Value::use_iterator UI = V->use_begin(), E = V->use_end(); UI!=E; ++UI) { 25238a8a4350db3e66a517dc179ba38439c66bb726a8Gabor Greif User *U = cast<Instruction>(*UI); 25248a8a4350db3e66a517dc179ba38439c66bb726a8Gabor Greif 25252e61849f45144f2f05d57b00947df7e101610694Chris Lattner if (LoadInst *LI = dyn_cast<LoadInst>(U)) { 25266e733d34ca487ab7ff8a6def018a933620393869Chris Lattner // Ignore non-volatile loads, they are always ok. 25272e61849f45144f2f05d57b00947df7e101610694Chris Lattner if (LI->isVolatile()) return false; 25282e61849f45144f2f05d57b00947df7e101610694Chris Lattner continue; 25292e61849f45144f2f05d57b00947df7e101610694Chris Lattner } 25306974302e3ff20746268721959efed807c7711bfcBob Wilson 25318a8a4350db3e66a517dc179ba38439c66bb726a8Gabor Greif if (BitCastInst *BCI = dyn_cast<BitCastInst>(U)) { 253279b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner // If uses of the bitcast are ok, we are ok. 25339174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky if (!isOnlyCopiedFromConstantGlobal(BCI, TheCopy, isOffset, 25349174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky LifetimeMarkers)) 253579b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner return false; 253679b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner continue; 253779b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner } 25388a8a4350db3e66a517dc179ba38439c66bb726a8Gabor Greif if (GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(U)) { 253979b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner // If the GEP has all zero indices, it doesn't offset the pointer. If it 254079b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner // doesn't, it does. 254179b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner if (!isOnlyCopiedFromConstantGlobal(GEP, TheCopy, 25429174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky isOffset || !GEP->hasAllZeroIndices(), 25439174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky LifetimeMarkers)) 254479b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner return false; 254579b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner continue; 254679b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner } 25476974302e3ff20746268721959efed807c7711bfcBob Wilson 25486248065194778c866164b0c10f09f0f0d91b91acChris Lattner if (CallSite CS = U) { 2549081f80078dccf02c1f9c61378ff88bbf1b4afb5eNick Lewycky // If this is the function being called then we treat it like a load and 2550081f80078dccf02c1f9c61378ff88bbf1b4afb5eNick Lewycky // ignore it. 2551081f80078dccf02c1f9c61378ff88bbf1b4afb5eNick Lewycky if (CS.isCallee(UI)) 2552081f80078dccf02c1f9c61378ff88bbf1b4afb5eNick Lewycky continue; 25536974302e3ff20746268721959efed807c7711bfcBob Wilson 25545389210e638401b8982b6de7c4e4a16999007035Duncan Sands // If this is a readonly/readnone call site, then we know it is just a 25555389210e638401b8982b6de7c4e4a16999007035Duncan Sands // load (but one that potentially returns the value itself), so we can 25565389210e638401b8982b6de7c4e4a16999007035Duncan Sands // ignore it if we know that the value isn't captured. 25575389210e638401b8982b6de7c4e4a16999007035Duncan Sands unsigned ArgNo = CS.getArgumentNo(UI); 25585389210e638401b8982b6de7c4e4a16999007035Duncan Sands if (CS.onlyReadsMemory() && 25595389210e638401b8982b6de7c4e4a16999007035Duncan Sands (CS.getInstruction()->use_empty() || 25605389210e638401b8982b6de7c4e4a16999007035Duncan Sands CS.paramHasAttr(ArgNo+1, Attribute::NoCapture))) 25615389210e638401b8982b6de7c4e4a16999007035Duncan Sands continue; 25625389210e638401b8982b6de7c4e4a16999007035Duncan Sands 25636248065194778c866164b0c10f09f0f0d91b91acChris Lattner // If this is being passed as a byval argument, the caller is making a 25646248065194778c866164b0c10f09f0f0d91b91acChris Lattner // copy, so it is only a read of the alloca. 25656248065194778c866164b0c10f09f0f0d91b91acChris Lattner if (CS.paramHasAttr(ArgNo+1, Attribute::ByVal)) 25666248065194778c866164b0c10f09f0f0d91b91acChris Lattner continue; 25676248065194778c866164b0c10f09f0f0d91b91acChris Lattner } 25686974302e3ff20746268721959efed807c7711bfcBob Wilson 25699174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky // Lifetime intrinsics can be handled by the caller. 25709174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(U)) { 25719174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky if (II->getIntrinsicID() == Intrinsic::lifetime_start || 25729174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky II->getIntrinsicID() == Intrinsic::lifetime_end) { 25739174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky assert(II->use_empty() && "Lifetime markers have no result to use!"); 25749174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky LifetimeMarkers.push_back(II); 25759174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky continue; 25769174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky } 25779174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky } 25789174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky 257979b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner // If this is isn't our memcpy/memmove, reject it as something we can't 258079b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner // handle. 258131d80103d56c026403d7fb6c50833664ff63ddcbChris Lattner MemTransferInst *MI = dyn_cast<MemTransferInst>(U); 258231d80103d56c026403d7fb6c50833664ff63ddcbChris Lattner if (MI == 0) 258379b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner return false; 25846974302e3ff20746268721959efed807c7711bfcBob Wilson 25852e61849f45144f2f05d57b00947df7e101610694Chris Lattner // If the transfer is using the alloca as a source of the transfer, then 25862e29ebd9e8efefe3ff926aa99cf2e5323665998eChris Lattner // ignore it since it is a load (unless the transfer is volatile). 25872e61849f45144f2f05d57b00947df7e101610694Chris Lattner if (UI.getOperandNo() == 1) { 25882e61849f45144f2f05d57b00947df7e101610694Chris Lattner if (MI->isVolatile()) return false; 25892e61849f45144f2f05d57b00947df7e101610694Chris Lattner continue; 25902e61849f45144f2f05d57b00947df7e101610694Chris Lattner } 259179b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner 259279b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner // If we already have seen a copy, reject the second one. 259379b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner if (TheCopy) return false; 25946974302e3ff20746268721959efed807c7711bfcBob Wilson 259579b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner // If the pointer has been offset from the start of the alloca, we can't 259679b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner // safely handle this. 259779b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner if (isOffset) return false; 259879b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner 259979b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner // If the memintrinsic isn't using the alloca as the dest, reject it. 2600a6aac4c5bc22bb10c7adb11eee3f82c703af7002Gabor Greif if (UI.getOperandNo() != 0) return false; 26016974302e3ff20746268721959efed807c7711bfcBob Wilson 260279b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner // If the source of the memcpy/move is not a constant global, reject it. 260331d80103d56c026403d7fb6c50833664ff63ddcbChris Lattner if (!PointsToConstantGlobal(MI->getSource())) 260479b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner return false; 26056974302e3ff20746268721959efed807c7711bfcBob Wilson 260679b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner // Otherwise, the transform is safe. Remember the copy instruction. 260779b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner TheCopy = MI; 260879b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner } 260979b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner return true; 261079b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner} 261179b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner 261279b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner/// isOnlyCopiedFromConstantGlobal - Return true if the specified alloca is only 261379b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner/// modified by a copy from a constant global. If we can prove this, we can 261479b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner/// replace any uses of the alloca with uses of the global directly. 26159174d5c7383490d79b6a483d73cded54e32275d6Nick LewyckyMemTransferInst * 26169174d5c7383490d79b6a483d73cded54e32275d6Nick LewyckySROA::isOnlyCopiedFromConstantGlobal(AllocaInst *AI, 26179174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky SmallVector<Instruction*, 4> &ToDelete) { 261831d80103d56c026403d7fb6c50833664ff63ddcbChris Lattner MemTransferInst *TheCopy = 0; 26199174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky if (::isOnlyCopiedFromConstantGlobal(AI, TheCopy, false, ToDelete)) 262079b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner return TheCopy; 262179b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner return 0; 262279b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner} 2623