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// 16c9f27ee842b633662f381b6e2cbd6de96b5bf905Chad Rosier// This combines a simple SRoA algorithm with the Mem2Reg algorithm because they 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" 334fd3c5957e6a272b60d6446e745136187d07f812Devang Patel#include "llvm/Analysis/DebugInfo.h" 34c827939046670a9800659b83e2048f1d3a79a531Cameron Zwarich#include "llvm/Analysis/DIBuilder.h" 35b1686c32fc694636cbf15a59b23b2a741b65ecf4Cameron Zwarich#include "llvm/Analysis/Dominators.h" 36c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner#include "llvm/Analysis/Loads.h" 375034dd318a9dfa0dc45a3ac01e58e60f2aa2498dDan Gohman#include "llvm/Analysis/ValueTracking.h" 3838aec325604635380421a27e39ab06d55ed2458dChris Lattner#include "llvm/Target/TargetData.h" 3938aec325604635380421a27e39ab06d55ed2458dChris Lattner#include "llvm/Transforms/Utils/PromoteMemToReg.h" 404afc90dacf309999d8b7f6c2b4b0c56af346bab5Devang Patel#include "llvm/Transforms/Utils/Local.h" 41e0a1a5ba91df6817f9ffae7af65ed0bda66f7620Chris Lattner#include "llvm/Transforms/Utils/SSAUpdater.h" 42a9be1df6d7a9b5a07253d83a634ae5876e7e5550Chris Lattner#include "llvm/Support/CallSite.h" 439525528a7dc5462b6374d38c81ba5c07b11741feChris Lattner#include "llvm/Support/Debug.h" 447d696d80409aad20bb5da0fc4eccab941dd371d4Torok Edwin#include "llvm/Support/ErrorHandling.h" 45a188894d67a3cc2516b25aae9b3cbdbff4b0babeChris Lattner#include "llvm/Support/GetElementPtrTypeIterator.h" 4665a650291d01638853aaf1e80fcc2fc86a785957Chris Lattner#include "llvm/Support/IRBuilder.h" 47a188894d67a3cc2516b25aae9b3cbdbff4b0babeChris Lattner#include "llvm/Support/MathExtras.h" 48bdff548e4dd577a72094d57b282de4e765643b96Chris Lattner#include "llvm/Support/raw_ostream.h" 49c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner#include "llvm/ADT/SetVector.h" 501ccd185cb49d81465a2901622e58ceae046d1d83Chris Lattner#include "llvm/ADT/SmallVector.h" 51551ccae044b0ff658fe629dd67edd5ffe75d10e8Reid Spencer#include "llvm/ADT/Statistic.h" 52d8664730942beb911327336d1f9db8e7efcd6813Chris Lattnerusing namespace llvm; 53d0fde30ce850b78371fd1386338350591f9ff494Brian Gaeke 540e5f499638c8d277b9dc4a4385712177c53b5681Chris LattnerSTATISTIC(NumReplaced, "Number of allocas broken up"); 550e5f499638c8d277b9dc4a4385712177c53b5681Chris LattnerSTATISTIC(NumPromoted, "Number of allocas promoted"); 56c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris LattnerSTATISTIC(NumAdjusted, "Number of scalar allocas adjusted to allow promotion"); 570e5f499638c8d277b9dc4a4385712177c53b5681Chris LattnerSTATISTIC(NumConverted, "Number of aggregates converted to scalar"); 5879b3bd395dc3303cde65e18e0524ed2f70268c99Chris LattnerSTATISTIC(NumGlobals, "Number of allocas copied from constant global"); 59ed7b41ea90a17c826f195acbc456c4bb733113d6Chris Lattner 600e5f499638c8d277b9dc4a4385712177c53b5681Chris Lattnernamespace { 613e8b6631e67e01e4960a7ba4668a50c596607473Chris Lattner struct SROA : public FunctionPass { 62b1686c32fc694636cbf15a59b23b2a741b65ecf4Cameron Zwarich SROA(int T, bool hasDT, char &ID) 63b1686c32fc694636cbf15a59b23b2a741b65ecf4Cameron Zwarich : FunctionPass(ID), HasDomTree(hasDT) { 64ff366850aa9956e167e78d4f5b57aae10d8c5779Devang Patel if (T == -1) 65b0e71edb6b33f822e001500dac90acf95faacea8Chris Lattner SRThreshold = 128; 66ff366850aa9956e167e78d4f5b57aae10d8c5779Devang Patel else 67ff366850aa9956e167e78d4f5b57aae10d8c5779Devang Patel SRThreshold = T; 68ff366850aa9956e167e78d4f5b57aae10d8c5779Devang Patel } 69794fd75c67a2cdc128d67342c6d88a504d186896Devang Patel 70ed7b41ea90a17c826f195acbc456c4bb733113d6Chris Lattner bool runOnFunction(Function &F); 71ed7b41ea90a17c826f195acbc456c4bb733113d6Chris Lattner 7238aec325604635380421a27e39ab06d55ed2458dChris Lattner bool performScalarRepl(Function &F); 7338aec325604635380421a27e39ab06d55ed2458dChris Lattner bool performPromotion(Function &F); 7438aec325604635380421a27e39ab06d55ed2458dChris Lattner 75ed7b41ea90a17c826f195acbc456c4bb733113d6Chris Lattner private: 76b1686c32fc694636cbf15a59b23b2a741b65ecf4Cameron Zwarich bool HasDomTree; 7756c3852fb46b7754ad89b998b5968cff0c3937eeChris Lattner TargetData *TD; 786974302e3ff20746268721959efed807c7711bfcBob Wilson 79b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson /// DeadInsts - Keep track of instructions we have made dead, so that 80b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson /// we can remove them after we are done working. 81b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson SmallVector<Value*, 32> DeadInsts; 82b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson 8339a1c04323a5993d6b2993e615ec44c16e19aeeaChris Lattner /// AllocaInfo - When analyzing uses of an alloca instruction, this captures 8439a1c04323a5993d6b2993e615ec44c16e19aeeaChris Lattner /// information about the uses. All these fields are initialized to false 8539a1c04323a5993d6b2993e615ec44c16e19aeeaChris Lattner /// and set to true when something is learned. 8639a1c04323a5993d6b2993e615ec44c16e19aeeaChris Lattner struct AllocaInfo { 876c95d24927b11fb76bc3e76ebe6a8198d74fc178Chris Lattner /// The alloca to promote. 886c95d24927b11fb76bc3e76ebe6a8198d74fc178Chris Lattner AllocaInst *AI; 896c95d24927b11fb76bc3e76ebe6a8198d74fc178Chris Lattner 90145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner /// CheckedPHIs - This is a set of verified PHI nodes, to prevent infinite 91145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner /// looping and avoid redundant work. 92145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner SmallPtrSet<PHINode*, 8> CheckedPHIs; 93145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner 9439a1c04323a5993d6b2993e615ec44c16e19aeeaChris Lattner /// isUnsafe - This is set to true if the alloca cannot be SROA'd. 9539a1c04323a5993d6b2993e615ec44c16e19aeeaChris Lattner bool isUnsafe : 1; 966974302e3ff20746268721959efed807c7711bfcBob Wilson 9739a1c04323a5993d6b2993e615ec44c16e19aeeaChris Lattner /// isMemCpySrc - This is true if this aggregate is memcpy'd from. 9839a1c04323a5993d6b2993e615ec44c16e19aeeaChris Lattner bool isMemCpySrc : 1; 9939a1c04323a5993d6b2993e615ec44c16e19aeeaChris Lattner 10033b0b8d242de8d428f11e77ea734a08b47797216Zhou Sheng /// isMemCpyDst - This is true if this aggregate is memcpy'd into. 10139a1c04323a5993d6b2993e615ec44c16e19aeeaChris Lattner bool isMemCpyDst : 1; 10239a1c04323a5993d6b2993e615ec44c16e19aeeaChris Lattner 1037e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner /// hasSubelementAccess - This is true if a subelement of the alloca is 1047e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner /// ever accessed, or false if the alloca is only accessed with mem 1057e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner /// intrinsics or load/store that only access the entire alloca at once. 1067e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner bool hasSubelementAccess : 1; 1077e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner 1087e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner /// hasALoadOrStore - This is true if there are any loads or stores to it. 1097e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner /// The alloca may just be accessed with memcpy, for example, which would 1107e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner /// not set this. 1117e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner bool hasALoadOrStore : 1; 1127e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner 1136c95d24927b11fb76bc3e76ebe6a8198d74fc178Chris Lattner explicit AllocaInfo(AllocaInst *ai) 1146c95d24927b11fb76bc3e76ebe6a8198d74fc178Chris Lattner : AI(ai), isUnsafe(false), isMemCpySrc(false), isMemCpyDst(false), 1157e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner hasSubelementAccess(false), hasALoadOrStore(false) {} 11639a1c04323a5993d6b2993e615ec44c16e19aeeaChris Lattner }; 1176974302e3ff20746268721959efed807c7711bfcBob Wilson 118ff366850aa9956e167e78d4f5b57aae10d8c5779Devang Patel unsigned SRThreshold; 119ff366850aa9956e167e78d4f5b57aae10d8c5779Devang Patel 120d01a0da090407762fe3b770d84f049d72d06467eChris Lattner void MarkUnsafe(AllocaInfo &I, Instruction *User) { 121d01a0da090407762fe3b770d84f049d72d06467eChris Lattner I.isUnsafe = true; 122d01a0da090407762fe3b770d84f049d72d06467eChris Lattner DEBUG(dbgs() << " Transformation preventing inst: " << *User << '\n'); 123d01a0da090407762fe3b770d84f049d72d06467eChris Lattner } 12439a1c04323a5993d6b2993e615ec44c16e19aeeaChris Lattner 1256c146eefbf75875250af37a0f1ea70fc6b4716eeVictor Hernandez bool isSafeAllocaToScalarRepl(AllocaInst *AI); 12639a1c04323a5993d6b2993e615ec44c16e19aeeaChris Lattner 1276c95d24927b11fb76bc3e76ebe6a8198d74fc178Chris Lattner void isSafeForScalarRepl(Instruction *I, uint64_t Offset, AllocaInfo &Info); 128145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner void isSafePHISelectUseForScalarRepl(Instruction *User, uint64_t Offset, 129145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner AllocaInfo &Info); 1306c95d24927b11fb76bc3e76ebe6a8198d74fc178Chris Lattner void isSafeGEP(GetElementPtrInst *GEPI, uint64_t &Offset, AllocaInfo &Info); 1316c95d24927b11fb76bc3e76ebe6a8198d74fc178Chris Lattner void isSafeMemAccess(uint64_t Offset, uint64_t MemSize, 132db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *MemOpType, bool isStore, AllocaInfo &Info, 133145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner Instruction *TheAccess, bool AllowWholeAccess); 134db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner bool TypeHasComponent(Type *T, uint64_t Offset, uint64_t Size); 135db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner uint64_t FindElementAndOffset(Type *&T, uint64_t &Offset, 136db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *&IdxTy); 1376974302e3ff20746268721959efed807c7711bfcBob Wilson 1386974302e3ff20746268721959efed807c7711bfcBob Wilson void DoScalarReplacement(AllocaInst *AI, 1397b929dad59785f62a66f7c58615082f98441e95eVictor Hernandez std::vector<AllocaInst*> &WorkList); 140b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson void DeleteDeadInstructions(); 1416974302e3ff20746268721959efed807c7711bfcBob Wilson 142b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson void RewriteForScalarRepl(Instruction *I, AllocaInst *AI, uint64_t Offset, 143b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson SmallVector<AllocaInst*, 32> &NewElts); 144b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson void RewriteBitCast(BitCastInst *BC, AllocaInst *AI, uint64_t Offset, 145b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson SmallVector<AllocaInst*, 32> &NewElts); 146b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson void RewriteGEP(GetElementPtrInst *GEPI, AllocaInst *AI, uint64_t Offset, 147b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson SmallVector<AllocaInst*, 32> &NewElts); 1485a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky void RewriteLifetimeIntrinsic(IntrinsicInst *II, AllocaInst *AI, 1495a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky uint64_t Offset, 1505a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky SmallVector<AllocaInst*, 32> &NewElts); 151b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson void RewriteMemIntrinUserOfAlloca(MemIntrinsic *MI, Instruction *Inst, 1527b929dad59785f62a66f7c58615082f98441e95eVictor Hernandez AllocaInst *AI, 153d93afec1dbbb1abb3df55e2e007b5f256d09f84aChris Lattner SmallVector<AllocaInst*, 32> &NewElts); 1547b929dad59785f62a66f7c58615082f98441e95eVictor Hernandez void RewriteStoreUserOfWholeAlloca(StoreInst *SI, AllocaInst *AI, 155d2fa781169175b827e50953a1d0b7edc6b0c4801Chris Lattner SmallVector<AllocaInst*, 32> &NewElts); 1567b929dad59785f62a66f7c58615082f98441e95eVictor Hernandez void RewriteLoadUserOfWholeAlloca(LoadInst *LI, AllocaInst *AI, 1576e733d34ca487ab7ff8a6def018a933620393869Chris Lattner SmallVector<AllocaInst*, 32> &NewElts); 1586974302e3ff20746268721959efed807c7711bfcBob Wilson 1599174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky static MemTransferInst *isOnlyCopiedFromConstantGlobal( 1609174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky AllocaInst *AI, SmallVector<Instruction*, 4> &ToDelete); 161ed7b41ea90a17c826f195acbc456c4bb733113d6Chris Lattner }; 162b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner 163b1686c32fc694636cbf15a59b23b2a741b65ecf4Cameron Zwarich // SROA_DT - SROA that uses DominatorTree. 164b1686c32fc694636cbf15a59b23b2a741b65ecf4Cameron Zwarich struct SROA_DT : public SROA { 165b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner static char ID; 166b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner public: 167b1686c32fc694636cbf15a59b23b2a741b65ecf4Cameron Zwarich SROA_DT(int T = -1) : SROA(T, true, ID) { 168b1686c32fc694636cbf15a59b23b2a741b65ecf4Cameron Zwarich initializeSROA_DTPass(*PassRegistry::getPassRegistry()); 169b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner } 170b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner 171b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner // getAnalysisUsage - This pass does not require any passes, but we know it 172b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner // will not alter the CFG, so say so. 173b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner virtual void getAnalysisUsage(AnalysisUsage &AU) const { 174b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner AU.addRequired<DominatorTree>(); 175b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner AU.setPreservesCFG(); 176b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner } 177b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner }; 178b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner 179b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner // SROA_SSAUp - SROA that uses SSAUpdater. 180b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner struct SROA_SSAUp : public SROA { 181b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner static char ID; 182b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner public: 183b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner SROA_SSAUp(int T = -1) : SROA(T, false, ID) { 184b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner initializeSROA_SSAUpPass(*PassRegistry::getPassRegistry()); 185b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner } 186b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner 187b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner // getAnalysisUsage - This pass does not require any passes, but we know it 188b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner // will not alter the CFG, so say so. 189b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner virtual void getAnalysisUsage(AnalysisUsage &AU) const { 190b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner AU.setPreservesCFG(); 191b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner } 192b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner }; 193b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner 194ed7b41ea90a17c826f195acbc456c4bb733113d6Chris Lattner} 195ed7b41ea90a17c826f195acbc456c4bb733113d6Chris Lattner 196b1686c32fc694636cbf15a59b23b2a741b65ecf4Cameron Zwarichchar SROA_DT::ID = 0; 197b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattnerchar SROA_SSAUp::ID = 0; 198b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner 199b1686c32fc694636cbf15a59b23b2a741b65ecf4Cameron ZwarichINITIALIZE_PASS_BEGIN(SROA_DT, "scalarrepl", 200b1686c32fc694636cbf15a59b23b2a741b65ecf4Cameron Zwarich "Scalar Replacement of Aggregates (DT)", false, false) 2012ab36d350293c77fc8941ce1023e4899df7e3a82Owen AndersonINITIALIZE_PASS_DEPENDENCY(DominatorTree) 202b1686c32fc694636cbf15a59b23b2a741b65ecf4Cameron ZwarichINITIALIZE_PASS_END(SROA_DT, "scalarrepl", 203b1686c32fc694636cbf15a59b23b2a741b65ecf4Cameron Zwarich "Scalar Replacement of Aggregates (DT)", false, false) 204b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner 205b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris LattnerINITIALIZE_PASS_BEGIN(SROA_SSAUp, "scalarrepl-ssa", 206b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner "Scalar Replacement of Aggregates (SSAUp)", false, false) 207b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris LattnerINITIALIZE_PASS_END(SROA_SSAUp, "scalarrepl-ssa", 208b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner "Scalar Replacement of Aggregates (SSAUp)", false, false) 209844731a7f1909f55935e3514c9e713a62d67662eDan Gohman 210d0fde30ce850b78371fd1386338350591f9ff494Brian Gaeke// Public interface to the ScalarReplAggregates pass 211b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris LattnerFunctionPass *llvm::createScalarReplAggregatesPass(int Threshold, 212b1686c32fc694636cbf15a59b23b2a741b65ecf4Cameron Zwarich bool UseDomTree) { 213b1686c32fc694636cbf15a59b23b2a741b65ecf4Cameron Zwarich if (UseDomTree) 214b1686c32fc694636cbf15a59b23b2a741b65ecf4Cameron Zwarich return new SROA_DT(Threshold); 215b352d6eb49927a7c707cbd9046cfc525b0c3f2d7Chris Lattner return new SROA_SSAUp(Threshold); 216ff366850aa9956e167e78d4f5b57aae10d8c5779Devang Patel} 217ed7b41ea90a17c826f195acbc456c4bb733113d6Chris Lattner 218ed7b41ea90a17c826f195acbc456c4bb733113d6Chris Lattner 2194cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner//===----------------------------------------------------------------------===// 2204cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner// Convert To Scalar Optimization. 2214cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner//===----------------------------------------------------------------------===// 222963a97f1a365c8d09ca681e922371f9ec3473ee8Chris Lattner 223c4472072641f702dbd99ae12b7da089e75c44a99Chris Lattnernamespace { 224a001b664988f759d194f3d5d880c61449219fc2eChris Lattner/// ConvertToScalarInfo - This class implements the "Convert To Scalar" 225a001b664988f759d194f3d5d880c61449219fc2eChris Lattner/// optimization, which scans the uses of an alloca and determines if it can 226a001b664988f759d194f3d5d880c61449219fc2eChris Lattner/// rewrite it in terms of a single new alloca that can be mem2reg'd. 2274cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattnerclass ConvertToScalarInfo { 228d4c9c3e6b97e095c24d989c0f5ce763f90100ef1Cameron Zwarich /// AllocaSize - The size of the alloca being considered in bytes. 229c4472072641f702dbd99ae12b7da089e75c44a99Chris Lattner unsigned AllocaSize; 230593375d04ab32be0161607a741d310172f142b93Chris Lattner const TargetData &TD; 2316974302e3ff20746268721959efed807c7711bfcBob Wilson 232a0bada729ffaa1bfc80ef25935bdc5a67432708fChris Lattner /// IsNotTrivial - This is set to true if there is some access to the object 233a001b664988f759d194f3d5d880c61449219fc2eChris Lattner /// which means that mem2reg can't promote it. 234c4472072641f702dbd99ae12b7da089e75c44a99Chris Lattner bool IsNotTrivial; 2356974302e3ff20746268721959efed807c7711bfcBob Wilson 236deb74f21f205aa245568ea965132eb076a3bf88cCameron Zwarich /// ScalarKind - Tracks the kind of alloca being considered for promotion, 237deb74f21f205aa245568ea965132eb076a3bf88cCameron Zwarich /// computed based on the uses of the alloca rather than the LLVM type system. 238deb74f21f205aa245568ea965132eb076a3bf88cCameron Zwarich enum { 239deb74f21f205aa245568ea965132eb076a3bf88cCameron Zwarich Unknown, 2405179782cf03cfabfe89df71677e0ffc772b5fdd5Cameron Zwarich 24115cd80c16b4e63b99dcbe45d2baa9456d414aacaCameron Zwarich // Accesses via GEPs that are consistent with element access of a vector 2425179782cf03cfabfe89df71677e0ffc772b5fdd5Cameron Zwarich // type. This will not be converted into a vector unless there is a later 2435179782cf03cfabfe89df71677e0ffc772b5fdd5Cameron Zwarich // access using an actual vector type. 2445179782cf03cfabfe89df71677e0ffc772b5fdd5Cameron Zwarich ImplicitVector, 2455179782cf03cfabfe89df71677e0ffc772b5fdd5Cameron Zwarich 24615cd80c16b4e63b99dcbe45d2baa9456d414aacaCameron Zwarich // Accesses via vector operations and GEPs that are consistent with the 24715cd80c16b4e63b99dcbe45d2baa9456d414aacaCameron Zwarich // layout of a vector type. 248deb74f21f205aa245568ea965132eb076a3bf88cCameron Zwarich Vector, 2495179782cf03cfabfe89df71677e0ffc772b5fdd5Cameron Zwarich 2505179782cf03cfabfe89df71677e0ffc772b5fdd5Cameron Zwarich // An integer bag-of-bits with bitwise operations for insertion and 2515179782cf03cfabfe89df71677e0ffc772b5fdd5Cameron Zwarich // extraction. Any combination of types can be converted into this kind 2525179782cf03cfabfe89df71677e0ffc772b5fdd5Cameron Zwarich // of scalar. 253deb74f21f205aa245568ea965132eb076a3bf88cCameron Zwarich Integer 254deb74f21f205aa245568ea965132eb076a3bf88cCameron Zwarich } ScalarKind; 255deb74f21f205aa245568ea965132eb076a3bf88cCameron Zwarich 256a001b664988f759d194f3d5d880c61449219fc2eChris Lattner /// VectorTy - This tracks the type that we should promote the vector to if 257a001b664988f759d194f3d5d880c61449219fc2eChris Lattner /// it is possible to turn it into a vector. This starts out null, and if it 258a001b664988f759d194f3d5d880c61449219fc2eChris Lattner /// isn't possible to turn into a vector type, it gets set to VoidTy. 259db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner VectorType *VectorTy; 2606974302e3ff20746268721959efed807c7711bfcBob Wilson 2611bcdb6ffad79936a96b46080bf0fed867243b32aCameron Zwarich /// HadNonMemTransferAccess - True if there is at least one access to the 2621bcdb6ffad79936a96b46080bf0fed867243b32aCameron Zwarich /// alloca that is not a MemTransferInst. We don't want to turn structs into 2631bcdb6ffad79936a96b46080bf0fed867243b32aCameron Zwarich /// large integers unless there is some potential for optimization. 26485b0f468cf8390fca3ec356cd498ce0039dbad4fCameron Zwarich bool HadNonMemTransferAccess; 26585b0f468cf8390fca3ec356cd498ce0039dbad4fCameron Zwarich 2664cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattnerpublic: 267593375d04ab32be0161607a741d310172f142b93Chris Lattner explicit ConvertToScalarInfo(unsigned Size, const TargetData &td) 268deb74f21f205aa245568ea965132eb076a3bf88cCameron Zwarich : AllocaSize(Size), TD(td), IsNotTrivial(false), ScalarKind(Unknown), 2695179782cf03cfabfe89df71677e0ffc772b5fdd5Cameron Zwarich VectorTy(0), HadNonMemTransferAccess(false) { } 2706974302e3ff20746268721959efed807c7711bfcBob Wilson 271a001b664988f759d194f3d5d880c61449219fc2eChris Lattner AllocaInst *TryConvert(AllocaInst *AI); 2726974302e3ff20746268721959efed807c7711bfcBob Wilson 2734cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattnerprivate: 274593375d04ab32be0161607a741d310172f142b93Chris Lattner bool CanConvertToScalar(Value *V, uint64_t Offset); 275db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner void MergeInTypeForLoadOrStore(Type *In, uint64_t Offset); 276db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner bool MergeInVectorType(VectorType *VInTy, uint64_t Offset); 277593375d04ab32be0161607a741d310172f142b93Chris Lattner void ConvertUsesToScalar(Value *Ptr, AllocaInst *NewAI, uint64_t Offset); 2786974302e3ff20746268721959efed807c7711bfcBob Wilson 279db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Value *ConvertScalar_ExtractValue(Value *NV, Type *ToType, 280593375d04ab32be0161607a741d310172f142b93Chris Lattner uint64_t Offset, IRBuilder<> &Builder); 281593375d04ab32be0161607a741d310172f142b93Chris Lattner Value *ConvertScalar_InsertValue(Value *StoredVal, Value *ExistingVal, 282593375d04ab32be0161607a741d310172f142b93Chris Lattner uint64_t Offset, IRBuilder<> &Builder); 283c4472072641f702dbd99ae12b7da089e75c44a99Chris Lattner}; 284c4472072641f702dbd99ae12b7da089e75c44a99Chris Lattner} // end anonymous namespace. 285c4472072641f702dbd99ae12b7da089e75c44a99Chris Lattner 28691abace4ef6fdfe01bcebfb8e90938e71f8a5c4fChris Lattner 287a001b664988f759d194f3d5d880c61449219fc2eChris Lattner/// TryConvert - Analyze the specified alloca, and if it is safe to do so, 288a001b664988f759d194f3d5d880c61449219fc2eChris Lattner/// rewrite it to be a new alloca which is mem2reg'able. This returns the new 289a001b664988f759d194f3d5d880c61449219fc2eChris Lattner/// alloca if possible or null if not. 290a001b664988f759d194f3d5d880c61449219fc2eChris LattnerAllocaInst *ConvertToScalarInfo::TryConvert(AllocaInst *AI) { 291a001b664988f759d194f3d5d880c61449219fc2eChris Lattner // If we can't convert this scalar, or if mem2reg can trivially do it, bail 292a001b664988f759d194f3d5d880c61449219fc2eChris Lattner // out. 293a001b664988f759d194f3d5d880c61449219fc2eChris Lattner if (!CanConvertToScalar(AI, 0) || !IsNotTrivial) 294a001b664988f759d194f3d5d880c61449219fc2eChris Lattner return 0; 2956974302e3ff20746268721959efed807c7711bfcBob Wilson 2965179782cf03cfabfe89df71677e0ffc772b5fdd5Cameron Zwarich // If an alloca has only memset / memcpy uses, it may still have an Unknown 2975179782cf03cfabfe89df71677e0ffc772b5fdd5Cameron Zwarich // ScalarKind. Treat it as an Integer below. 2985179782cf03cfabfe89df71677e0ffc772b5fdd5Cameron Zwarich if (ScalarKind == Unknown) 2995179782cf03cfabfe89df71677e0ffc772b5fdd5Cameron Zwarich ScalarKind = Integer; 3005179782cf03cfabfe89df71677e0ffc772b5fdd5Cameron Zwarich 3013ebb05d9a6bf6604a4b25770cfda1872983b03b2Cameron Zwarich if (ScalarKind == Vector && VectorTy->getBitWidth() != AllocaSize * 8) 3023ebb05d9a6bf6604a4b25770cfda1872983b03b2Cameron Zwarich ScalarKind = Integer; 3033ebb05d9a6bf6604a4b25770cfda1872983b03b2Cameron Zwarich 304a001b664988f759d194f3d5d880c61449219fc2eChris Lattner // If we were able to find a vector type that can handle this with 305a001b664988f759d194f3d5d880c61449219fc2eChris Lattner // insert/extract elements, and if there was at least one use that had 306a001b664988f759d194f3d5d880c61449219fc2eChris Lattner // a vector type, promote this to a vector. We don't want to promote 307a001b664988f759d194f3d5d880c61449219fc2eChris Lattner // random stuff that doesn't use vectors (e.g. <9 x double>) because then 308a001b664988f759d194f3d5d880c61449219fc2eChris Lattner // we just get a lot of insert/extracts. If at least one vector is 309a001b664988f759d194f3d5d880c61449219fc2eChris Lattner // involved, then we probably really do have a union of vector/array. 310db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *NewTy; 3115b93d3ca6f9c6e81924063abb1487598906dcdabCameron Zwarich if (ScalarKind == Vector) { 3125b93d3ca6f9c6e81924063abb1487598906dcdabCameron Zwarich assert(VectorTy && "Missing type for vector scalar."); 313a001b664988f759d194f3d5d880c61449219fc2eChris Lattner DEBUG(dbgs() << "CONVERT TO VECTOR: " << *AI << "\n TYPE = " 314a001b664988f759d194f3d5d880c61449219fc2eChris Lattner << *VectorTy << '\n'); 315a001b664988f759d194f3d5d880c61449219fc2eChris Lattner NewTy = VectorTy; // Use the vector type. 316a001b664988f759d194f3d5d880c61449219fc2eChris Lattner } else { 31785b0f468cf8390fca3ec356cd498ce0039dbad4fCameron Zwarich unsigned BitWidth = AllocaSize * 8; 3185179782cf03cfabfe89df71677e0ffc772b5fdd5Cameron Zwarich if ((ScalarKind == ImplicitVector || ScalarKind == Integer) && 3195179782cf03cfabfe89df71677e0ffc772b5fdd5Cameron Zwarich !HadNonMemTransferAccess && !TD.fitsInLegalInteger(BitWidth)) 32085b0f468cf8390fca3ec356cd498ce0039dbad4fCameron Zwarich return 0; 32185b0f468cf8390fca3ec356cd498ce0039dbad4fCameron Zwarich 322a001b664988f759d194f3d5d880c61449219fc2eChris Lattner DEBUG(dbgs() << "CONVERT TO SCALAR INTEGER: " << *AI << "\n"); 323a001b664988f759d194f3d5d880c61449219fc2eChris Lattner // Create and insert the integer alloca. 32485b0f468cf8390fca3ec356cd498ce0039dbad4fCameron Zwarich NewTy = IntegerType::get(AI->getContext(), BitWidth); 325a001b664988f759d194f3d5d880c61449219fc2eChris Lattner } 326a001b664988f759d194f3d5d880c61449219fc2eChris Lattner AllocaInst *NewAI = new AllocaInst(NewTy, 0, "", AI->getParent()->begin()); 327a001b664988f759d194f3d5d880c61449219fc2eChris Lattner ConvertUsesToScalar(AI, NewAI, 0); 328a001b664988f759d194f3d5d880c61449219fc2eChris Lattner return NewAI; 329a001b664988f759d194f3d5d880c61449219fc2eChris Lattner} 330a001b664988f759d194f3d5d880c61449219fc2eChris Lattner 331c0e2607564c1259f2d2c56cbff8f78dc0853860dCameron Zwarich/// MergeInTypeForLoadOrStore - Add the 'In' type to the accumulated vector type 332c0e2607564c1259f2d2c56cbff8f78dc0853860dCameron Zwarich/// (VectorTy) so far at the offset specified by Offset (which is specified in 333c0e2607564c1259f2d2c56cbff8f78dc0853860dCameron Zwarich/// bytes). 3344cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// 335446d95224b35b0fef06200b950d45839f1d5f262Cameron Zwarich/// There are two cases we handle here: 3364cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// 1) A union of vector types of the same size and potentially its elements. 3374cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// Here we turn element accesses into insert/extract element operations. 3384cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// This promotes a <4 x float> with a store of float to the third element 3394cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// into a <4 x float> that uses insert element. 340446d95224b35b0fef06200b950d45839f1d5f262Cameron Zwarich/// 2) A fully general blob of memory, which we turn into some (potentially 3414cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// large) integer type with extract and insert operations where the loads 342a001b664988f759d194f3d5d880c61449219fc2eChris Lattner/// and stores would mutate the memory. We mark this by setting VectorTy 343a001b664988f759d194f3d5d880c61449219fc2eChris Lattner/// to VoidTy. 344db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattnervoid ConvertToScalarInfo::MergeInTypeForLoadOrStore(Type *In, 345c0e2607564c1259f2d2c56cbff8f78dc0853860dCameron Zwarich uint64_t Offset) { 346a001b664988f759d194f3d5d880c61449219fc2eChris Lattner // If we already decided to turn this into a blob of integer memory, there is 347a001b664988f759d194f3d5d880c61449219fc2eChris Lattner // nothing to be done. 348deb74f21f205aa245568ea965132eb076a3bf88cCameron Zwarich if (ScalarKind == Integer) 3494cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return; 3506974302e3ff20746268721959efed807c7711bfcBob Wilson 3514cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If this could be contributing to a vector, analyze it. 352c4472072641f702dbd99ae12b7da089e75c44a99Chris Lattner 3534cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If the In type is a vector that is the same size as the alloca, see if it 3544cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // matches the existing VecTy. 355db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner if (VectorType *VInTy = dyn_cast<VectorType>(In)) { 356c9ecd14cee020f884313b60f8696384d3e7848f7Cameron Zwarich if (MergeInVectorType(VInTy, Offset)) 3574cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return; 3584cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } else if (In->isFloatTy() || In->isDoubleTy() || 3594cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner (In->isIntegerTy() && In->getPrimitiveSizeInBits() >= 8 && 3604cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner isPowerOf2_32(In->getPrimitiveSizeInBits()))) { 3619827b78b51f285e90c2b1e5add9b28d10c88595cCameron Zwarich // Full width accesses can be ignored, because they can always be turned 3629827b78b51f285e90c2b1e5add9b28d10c88595cCameron Zwarich // into bitcasts. 3639827b78b51f285e90c2b1e5add9b28d10c88595cCameron Zwarich unsigned EltSize = In->getPrimitiveSizeInBits()/8; 364dd68912801861273dc3dca33cfc18357213049a4Cameron Zwarich if (EltSize == AllocaSize) 3659827b78b51f285e90c2b1e5add9b28d10c88595cCameron Zwarich return; 3665fc1282c1822d692ed1681cdc4c315950c6eb1d8Cameron Zwarich 3674cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If we're accessing something that could be an element of a vector, see 3684cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // if the implied vector agrees with what we already have and if Offset is 3694cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // compatible with it. 37096cc1d0dfbcf9c7ffffc65f0aa008ff532d444f4Cameron Zwarich if (Offset % EltSize == 0 && AllocaSize % EltSize == 0 && 371446d95224b35b0fef06200b950d45839f1d5f262Cameron Zwarich (!VectorTy || EltSize == VectorTy->getElementType() 372446d95224b35b0fef06200b950d45839f1d5f262Cameron Zwarich ->getPrimitiveSizeInBits()/8)) { 3735fc1282c1822d692ed1681cdc4c315950c6eb1d8Cameron Zwarich if (!VectorTy) { 3745179782cf03cfabfe89df71677e0ffc772b5fdd5Cameron Zwarich ScalarKind = ImplicitVector; 3754cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner VectorTy = VectorType::get(In, AllocaSize/EltSize); 3765fc1282c1822d692ed1681cdc4c315950c6eb1d8Cameron Zwarich } 377446d95224b35b0fef06200b950d45839f1d5f262Cameron Zwarich return; 3784cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 3794cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 3806974302e3ff20746268721959efed807c7711bfcBob Wilson 3814cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Otherwise, we have a case that we can't handle with an optimized vector 3824cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // form. We can still turn this into a large integer. 383deb74f21f205aa245568ea965132eb076a3bf88cCameron Zwarich ScalarKind = Integer; 3844cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner} 385c4472072641f702dbd99ae12b7da089e75c44a99Chris Lattner 386c0e2607564c1259f2d2c56cbff8f78dc0853860dCameron Zwarich/// MergeInVectorType - Handles the vector case of MergeInTypeForLoadOrStore, 387c0e2607564c1259f2d2c56cbff8f78dc0853860dCameron Zwarich/// returning true if the type was successfully merged and false otherwise. 388db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattnerbool ConvertToScalarInfo::MergeInVectorType(VectorType *VInTy, 389c9ecd14cee020f884313b60f8696384d3e7848f7Cameron Zwarich uint64_t Offset) { 390446d95224b35b0fef06200b950d45839f1d5f262Cameron Zwarich if (VInTy->getBitWidth()/8 == AllocaSize && Offset == 0) { 391446d95224b35b0fef06200b950d45839f1d5f262Cameron Zwarich // If we're storing/loading a vector of the right size, allow it as a 392446d95224b35b0fef06200b950d45839f1d5f262Cameron Zwarich // vector. If this the first vector we see, remember the type so that 393446d95224b35b0fef06200b950d45839f1d5f262Cameron Zwarich // we know the element size. If this is a subsequent access, ignore it 394446d95224b35b0fef06200b950d45839f1d5f262Cameron Zwarich // even if it is a differing type but the same size. Worst case we can 395446d95224b35b0fef06200b950d45839f1d5f262Cameron Zwarich // bitcast the resultant vectors. 396446d95224b35b0fef06200b950d45839f1d5f262Cameron Zwarich if (!VectorTy) 397446d95224b35b0fef06200b950d45839f1d5f262Cameron Zwarich VectorTy = VInTy; 3985179782cf03cfabfe89df71677e0ffc772b5fdd5Cameron Zwarich ScalarKind = Vector; 399b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich return true; 4005179782cf03cfabfe89df71677e0ffc772b5fdd5Cameron Zwarich } 401b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich 402446d95224b35b0fef06200b950d45839f1d5f262Cameron Zwarich return false; 403c9ecd14cee020f884313b60f8696384d3e7848f7Cameron Zwarich} 404c9ecd14cee020f884313b60f8696384d3e7848f7Cameron Zwarich 4054cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// CanConvertToScalar - V is a pointer. If we can convert the pointee and all 4064cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// its accesses to a single vector type, return true and set VecTy to 4074cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// the new type. If we could convert the alloca into a single promotable 4084cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// integer, return true but set VecTy to VoidTy. Further, if the use is not a 4094cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// completely trivial use that mem2reg could promote, set IsNotTrivial. Offset 4104cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// is the current offset from the base of the alloca being analyzed. 4114cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// 4124cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// If we see at least one access to the value that is as a vector type, set the 4134cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// SawVec flag. 4144cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattnerbool ConvertToScalarInfo::CanConvertToScalar(Value *V, uint64_t Offset) { 4154cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner for (Value::use_iterator UI = V->use_begin(), E = V->use_end(); UI!=E; ++UI) { 4164cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Instruction *User = cast<Instruction>(*UI); 4176974302e3ff20746268721959efed807c7711bfcBob Wilson 4184cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (LoadInst *LI = dyn_cast<LoadInst>(User)) { 4194cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Don't break volatile loads. 4202bc3d52b9ab422ee9f7e42a1a4e3b818e623a5f7Eli Friedman if (!LI->isSimple()) 4214cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return false; 4220488fb649a56b7fc89a5814df5308813f9e5a85dDale Johannesen // Don't touch MMX operations. 4230488fb649a56b7fc89a5814df5308813f9e5a85dDale Johannesen if (LI->getType()->isX86_MMXTy()) 4240488fb649a56b7fc89a5814df5308813f9e5a85dDale Johannesen return false; 42585b0f468cf8390fca3ec356cd498ce0039dbad4fCameron Zwarich HadNonMemTransferAccess = true; 426c0e2607564c1259f2d2c56cbff8f78dc0853860dCameron Zwarich MergeInTypeForLoadOrStore(LI->getType(), Offset); 427add2bd7f5941537a97a41e037ae2277fbeed0b4fChris Lattner continue; 428add2bd7f5941537a97a41e037ae2277fbeed0b4fChris Lattner } 4296974302e3ff20746268721959efed807c7711bfcBob Wilson 4304cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (StoreInst *SI = dyn_cast<StoreInst>(User)) { 4314cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Storing the pointer, not into the value? 4322bc3d52b9ab422ee9f7e42a1a4e3b818e623a5f7Eli Friedman if (SI->getOperand(0) == V || !SI->isSimple()) return false; 4330488fb649a56b7fc89a5814df5308813f9e5a85dDale Johannesen // Don't touch MMX operations. 4340488fb649a56b7fc89a5814df5308813f9e5a85dDale Johannesen if (SI->getOperand(0)->getType()->isX86_MMXTy()) 4350488fb649a56b7fc89a5814df5308813f9e5a85dDale Johannesen return false; 43685b0f468cf8390fca3ec356cd498ce0039dbad4fCameron Zwarich HadNonMemTransferAccess = true; 437c0e2607564c1259f2d2c56cbff8f78dc0853860dCameron Zwarich MergeInTypeForLoadOrStore(SI->getOperand(0)->getType(), Offset); 4387809ecd5b019d26498499121f4d9c0b7de2f0a14Chris Lattner continue; 4397809ecd5b019d26498499121f4d9c0b7de2f0a14Chris Lattner } 4406974302e3ff20746268721959efed807c7711bfcBob Wilson 4414cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (BitCastInst *BCI = dyn_cast<BitCastInst>(User)) { 4425a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky if (!onlyUsedByLifetimeMarkers(BCI)) 4435a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky IsNotTrivial = true; // Can't be mem2reg'd. 4444cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (!CanConvertToScalar(BCI, Offset)) 4454cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return false; 4463992feb075b27ff37b63017078a977206f97d10dBob Wilson continue; 4473992feb075b27ff37b63017078a977206f97d10dBob Wilson } 4483992feb075b27ff37b63017078a977206f97d10dBob Wilson 4494cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(User)) { 4504cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If this is a GEP with a variable indices, we can't handle it. 4514cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (!GEP->hasAllConstantIndices()) 4524cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return false; 4536974302e3ff20746268721959efed807c7711bfcBob Wilson 4544cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Compute the offset that this GEP adds to the pointer. 4554cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner SmallVector<Value*, 8> Indices(GEP->op_begin()+1, GEP->op_end()); 4561608769abeb1430dc34f31ffac0d9850f99ae36aNadav Rotem if (!GEP->getPointerOperandType()->isPointerTy()) 4571608769abeb1430dc34f31ffac0d9850f99ae36aNadav Rotem return false; 4584cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t GEPOffset = TD.getIndexedOffset(GEP->getPointerOperandType(), 4598fbbb3980755d74539a0aed02bc18842ed2bd18dJay Foad Indices); 4604cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // See if all uses can be converted. 4614cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (!CanConvertToScalar(GEP, Offset+GEPOffset)) 4624cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return false; 463a001b664988f759d194f3d5d880c61449219fc2eChris Lattner IsNotTrivial = true; // Can't be mem2reg'd. 46485b0f468cf8390fca3ec356cd498ce0039dbad4fCameron Zwarich HadNonMemTransferAccess = true; 4657809ecd5b019d26498499121f4d9c0b7de2f0a14Chris Lattner continue; 4664cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 467ed7b41ea90a17c826f195acbc456c4bb733113d6Chris Lattner 4684cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If this is a constant sized memset of a constant value (e.g. 0) we can 4694cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // handle it. 4704cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (MemSetInst *MSI = dyn_cast<MemSetInst>(User)) { 4716be41eb7f00319f5ffa1a5435dcd1e81b3ce932dCameron Zwarich // Store of constant value. 4726be41eb7f00319f5ffa1a5435dcd1e81b3ce932dCameron Zwarich if (!isa<ConstantInt>(MSI->getValue())) 473a001b664988f759d194f3d5d880c61449219fc2eChris Lattner return false; 4746be41eb7f00319f5ffa1a5435dcd1e81b3ce932dCameron Zwarich 4756be41eb7f00319f5ffa1a5435dcd1e81b3ce932dCameron Zwarich // Store of constant size. 4766be41eb7f00319f5ffa1a5435dcd1e81b3ce932dCameron Zwarich ConstantInt *Len = dyn_cast<ConstantInt>(MSI->getLength()); 4776be41eb7f00319f5ffa1a5435dcd1e81b3ce932dCameron Zwarich if (!Len) 4786be41eb7f00319f5ffa1a5435dcd1e81b3ce932dCameron Zwarich return false; 4796be41eb7f00319f5ffa1a5435dcd1e81b3ce932dCameron Zwarich 4806be41eb7f00319f5ffa1a5435dcd1e81b3ce932dCameron Zwarich // If the size differs from the alloca, we can only convert the alloca to 4816be41eb7f00319f5ffa1a5435dcd1e81b3ce932dCameron Zwarich // an integer bag-of-bits. 4826be41eb7f00319f5ffa1a5435dcd1e81b3ce932dCameron Zwarich // FIXME: This should handle all of the cases that are currently accepted 4836be41eb7f00319f5ffa1a5435dcd1e81b3ce932dCameron Zwarich // as vector element insertions. 4846be41eb7f00319f5ffa1a5435dcd1e81b3ce932dCameron Zwarich if (Len->getZExtValue() != AllocaSize || Offset != 0) 4856be41eb7f00319f5ffa1a5435dcd1e81b3ce932dCameron Zwarich ScalarKind = Integer; 4866be41eb7f00319f5ffa1a5435dcd1e81b3ce932dCameron Zwarich 487a001b664988f759d194f3d5d880c61449219fc2eChris Lattner IsNotTrivial = true; // Can't be mem2reg'd. 48885b0f468cf8390fca3ec356cd498ce0039dbad4fCameron Zwarich HadNonMemTransferAccess = true; 489a001b664988f759d194f3d5d880c61449219fc2eChris Lattner continue; 4904cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 491fd93908ae8b9684fe71c239e3c6cfe13ff6a2663Misha Brukman 4924cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If this is a memcpy or memmove into or out of the whole allocation, we 4934cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // can handle it like a load or store of the scalar type. 4944cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (MemTransferInst *MTI = dyn_cast<MemTransferInst>(User)) { 495a001b664988f759d194f3d5d880c61449219fc2eChris Lattner ConstantInt *Len = dyn_cast<ConstantInt>(MTI->getLength()); 496a001b664988f759d194f3d5d880c61449219fc2eChris Lattner if (Len == 0 || Len->getZExtValue() != AllocaSize || Offset != 0) 497a001b664988f759d194f3d5d880c61449219fc2eChris Lattner return false; 4986974302e3ff20746268721959efed807c7711bfcBob Wilson 499a001b664988f759d194f3d5d880c61449219fc2eChris Lattner IsNotTrivial = true; // Can't be mem2reg'd. 500a001b664988f759d194f3d5d880c61449219fc2eChris Lattner continue; 501ed7b41ea90a17c826f195acbc456c4bb733113d6Chris Lattner } 5026974302e3ff20746268721959efed807c7711bfcBob Wilson 5035a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky // If this is a lifetime intrinsic, we can handle it. 5045a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(User)) { 5055a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky if (II->getIntrinsicID() == Intrinsic::lifetime_start || 5065a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky II->getIntrinsicID() == Intrinsic::lifetime_end) { 5075a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky continue; 5085a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky } 5095a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky } 5105a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky 5114cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Otherwise, we cannot handle this! 5124cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return false; 513a10b29b84b63c448b7cb423598d3a38b0f55cddbChris Lattner } 5146974302e3ff20746268721959efed807c7711bfcBob Wilson 5154cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return true; 516ed7b41ea90a17c826f195acbc456c4bb733113d6Chris Lattner} 517a59adc40153f3e0f9843952c127d179b5ebe6c4cChris Lattner 5184cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// ConvertUsesToScalar - Convert all of the users of Ptr to use the new alloca 5194cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// directly. This happens when we are converting an "integer union" to a 5204cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// single integer scalar, or when we are converting a "vector union" to a 5214cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// vector with insert/extractelement instructions. 5224cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// 5234cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// Offset is an offset from the original alloca, in bits that need to be 5244cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// shifted to the right. By the end of this, there should be no uses of Ptr. 5254cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattnervoid ConvertToScalarInfo::ConvertUsesToScalar(Value *Ptr, AllocaInst *NewAI, 5264cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t Offset) { 5274cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner while (!Ptr->use_empty()) { 5284cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Instruction *User = cast<Instruction>(Ptr->use_back()); 529b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson 5304cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (BitCastInst *CI = dyn_cast<BitCastInst>(User)) { 5314cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner ConvertUsesToScalar(CI, NewAI, Offset); 5324cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner CI->eraseFromParent(); 5334cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner continue; 5344cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 535b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson 5364cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(User)) { 5374cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Compute the offset that this GEP adds to the pointer. 5384cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner SmallVector<Value*, 8> Indices(GEP->op_begin()+1, GEP->op_end()); 5394cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t GEPOffset = TD.getIndexedOffset(GEP->getPointerOperandType(), 5408fbbb3980755d74539a0aed02bc18842ed2bd18dJay Foad Indices); 5414cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner ConvertUsesToScalar(GEP, NewAI, Offset+GEPOffset*8); 5424cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner GEP->eraseFromParent(); 5434cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner continue; 5444cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 5456974302e3ff20746268721959efed807c7711bfcBob Wilson 54661db1f56d0b717d67557bbb2a9d83af1449458cbChris Lattner IRBuilder<> Builder(User); 5476974302e3ff20746268721959efed807c7711bfcBob Wilson 5484cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (LoadInst *LI = dyn_cast<LoadInst>(User)) { 5494cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // The load is a bit extract from NewAI shifted right by Offset bits. 550a9390a4d5f5d568059a80970d22194b165d097a7Benjamin Kramer Value *LoadedVal = Builder.CreateLoad(NewAI); 5514cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *NewLoadVal 5524cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner = ConvertScalar_ExtractValue(LoadedVal, LI->getType(), Offset, Builder); 5534cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner LI->replaceAllUsesWith(NewLoadVal); 5544cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner LI->eraseFromParent(); 5554cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner continue; 5564cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 5576974302e3ff20746268721959efed807c7711bfcBob Wilson 5584cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (StoreInst *SI = dyn_cast<StoreInst>(User)) { 5594cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner assert(SI->getOperand(0) != Ptr && "Consistency error!"); 5604cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Instruction *Old = Builder.CreateLoad(NewAI, NewAI->getName()+".in"); 5614cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *New = ConvertScalar_InsertValue(SI->getOperand(0), Old, Offset, 5624cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Builder); 5634cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Builder.CreateStore(New, NewAI); 5644cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner SI->eraseFromParent(); 5656974302e3ff20746268721959efed807c7711bfcBob Wilson 5664cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If the load we just inserted is now dead, then the inserted store 5674cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // overwrote the entire thing. 5684cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (Old->use_empty()) 5694cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Old->eraseFromParent(); 5704cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner continue; 5714cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 5726974302e3ff20746268721959efed807c7711bfcBob Wilson 5734cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If this is a constant sized memset of a constant value (e.g. 0) we can 5744cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // transform it into a store of the expanded constant value. 5754cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (MemSetInst *MSI = dyn_cast<MemSetInst>(User)) { 5764cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner assert(MSI->getRawDest() == Ptr && "Consistency error!"); 57701b305f94c663d000e2128c7ea8c0c4e02e9eeb4Duncan Sands int64_t SNumBytes = cast<ConstantInt>(MSI->getLength())->getSExtValue(); 5781fe6bfca593404e261922990f230326934dda4d6Chris Lattner if (SNumBytes > 0 && (SNumBytes >> 32) == 0) { 5797e2fa3142aca46d9435a5804932ef76123c0cf71Aaron Ballman unsigned NumBytes = static_cast<unsigned>(SNumBytes); 5804cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner unsigned Val = cast<ConstantInt>(MSI->getValue())->getZExtValue(); 5816974302e3ff20746268721959efed807c7711bfcBob Wilson 5824cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Compute the value replicated the right number of times. 5834cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner APInt APVal(NumBytes*8, Val); 5842674089cefe519195e00bdf879647438cfb1cb0fDaniel Dunbar 5854cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Splat the value if non-zero. 5864cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (Val) 5874cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner for (unsigned i = 1; i != NumBytes; ++i) 5884cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner APVal |= APVal << 8; 5896974302e3ff20746268721959efed807c7711bfcBob Wilson 5904cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Instruction *Old = Builder.CreateLoad(NewAI, NewAI->getName()+".in"); 5914cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *New = ConvertScalar_InsertValue( 5924cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner ConstantInt::get(User->getContext(), APVal), 5934cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Old, Offset, Builder); 5944cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Builder.CreateStore(New, NewAI); 5956974302e3ff20746268721959efed807c7711bfcBob Wilson 5964cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If the load we just inserted is now dead, then the memset overwrote 5974cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // the entire thing. 5984cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (Old->use_empty()) 5996974302e3ff20746268721959efed807c7711bfcBob Wilson Old->eraseFromParent(); 6004cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 6014cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner MSI->eraseFromParent(); 6024cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner continue; 603b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson } 604fca55c8ac7d12e4139ad0ab7d74b76c47935aef6Daniel Dunbar 6054cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If this is a memcpy or memmove into or out of the whole allocation, we 6064cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // can handle it like a load or store of the scalar type. 6074cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (MemTransferInst *MTI = dyn_cast<MemTransferInst>(User)) { 6084cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner assert(Offset == 0 && "must be store to start of alloca"); 6096974302e3ff20746268721959efed807c7711bfcBob Wilson 6104cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If the source and destination are both to the same alloca, then this is 6114cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // a noop copy-to-self, just delete it. Otherwise, emit a load and store 6124cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // as appropriate. 613bd1801b5553c8be3960255a92738464e0010b6f6Dan Gohman AllocaInst *OrigAI = cast<AllocaInst>(GetUnderlyingObject(Ptr, &TD, 0)); 6146974302e3ff20746268721959efed807c7711bfcBob Wilson 615bd1801b5553c8be3960255a92738464e0010b6f6Dan Gohman if (GetUnderlyingObject(MTI->getSource(), &TD, 0) != OrigAI) { 6164cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Dest must be OrigAI, change this to be a load from the original 6174cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // pointer (bitcasted), then a store to our new alloca. 6184cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner assert(MTI->getRawDest() == Ptr && "Neither use is of pointer?"); 6194cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *SrcPtr = MTI->getSource(); 620db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner PointerType* SPTy = cast<PointerType>(SrcPtr->getType()); 621db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner PointerType* AIPTy = cast<PointerType>(NewAI->getType()); 622e90a6333c3a4514f88c8a3dddd10d9bcddcd6d85Mon P Wang if (SPTy->getAddressSpace() != AIPTy->getAddressSpace()) { 623e90a6333c3a4514f88c8a3dddd10d9bcddcd6d85Mon P Wang AIPTy = PointerType::get(AIPTy->getElementType(), 624e90a6333c3a4514f88c8a3dddd10d9bcddcd6d85Mon P Wang SPTy->getAddressSpace()); 625e90a6333c3a4514f88c8a3dddd10d9bcddcd6d85Mon P Wang } 626e90a6333c3a4514f88c8a3dddd10d9bcddcd6d85Mon P Wang SrcPtr = Builder.CreateBitCast(SrcPtr, AIPTy); 627e90a6333c3a4514f88c8a3dddd10d9bcddcd6d85Mon P Wang 6284cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner LoadInst *SrcVal = Builder.CreateLoad(SrcPtr, "srcval"); 6294cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner SrcVal->setAlignment(MTI->getAlignment()); 6304cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Builder.CreateStore(SrcVal, NewAI); 631bd1801b5553c8be3960255a92738464e0010b6f6Dan Gohman } else if (GetUnderlyingObject(MTI->getDest(), &TD, 0) != OrigAI) { 6324cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Src must be OrigAI, change this to be a load from NewAI then a store 6334cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // through the original dest pointer (bitcasted). 6344cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner assert(MTI->getRawSource() == Ptr && "Neither use is of pointer?"); 6354cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner LoadInst *SrcVal = Builder.CreateLoad(NewAI, "srcval"); 636b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson 637db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner PointerType* DPTy = cast<PointerType>(MTI->getDest()->getType()); 638db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner PointerType* AIPTy = cast<PointerType>(NewAI->getType()); 639e90a6333c3a4514f88c8a3dddd10d9bcddcd6d85Mon P Wang if (DPTy->getAddressSpace() != AIPTy->getAddressSpace()) { 640e90a6333c3a4514f88c8a3dddd10d9bcddcd6d85Mon P Wang AIPTy = PointerType::get(AIPTy->getElementType(), 641e90a6333c3a4514f88c8a3dddd10d9bcddcd6d85Mon P Wang DPTy->getAddressSpace()); 642e90a6333c3a4514f88c8a3dddd10d9bcddcd6d85Mon P Wang } 643e90a6333c3a4514f88c8a3dddd10d9bcddcd6d85Mon P Wang Value *DstPtr = Builder.CreateBitCast(MTI->getDest(), AIPTy); 644e90a6333c3a4514f88c8a3dddd10d9bcddcd6d85Mon P Wang 6454cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner StoreInst *NewStore = Builder.CreateStore(SrcVal, DstPtr); 6464cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner NewStore->setAlignment(MTI->getAlignment()); 6474cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } else { 6484cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Noop transfer. Src == Dst 6494cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 6505fac55fafb53fde5c548bcd08e07418e9d8e549fMatthijs Kooijman 6514cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner MTI->eraseFromParent(); 6524cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner continue; 6534cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 6546974302e3ff20746268721959efed807c7711bfcBob Wilson 6555a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(User)) { 6565a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky if (II->getIntrinsicID() == Intrinsic::lifetime_start || 6575a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky II->getIntrinsicID() == Intrinsic::lifetime_end) { 6585a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky // There's no need to preserve these, as the resulting alloca will be 6595a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky // converted to a register anyways. 6605a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky II->eraseFromParent(); 6615a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky continue; 6625a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky } 6635a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky } 6645a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky 6654cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner llvm_unreachable("Unsupported operation!"); 66688e6dc8bf14e8a98888f62173a6581386b8d29a0Chris Lattner } 6672674089cefe519195e00bdf879647438cfb1cb0fDaniel Dunbar} 6682674089cefe519195e00bdf879647438cfb1cb0fDaniel Dunbar 6694cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// ConvertScalar_ExtractValue - Extract a value of type ToType from an integer 6704cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// or vector value FromVal, extracting the bits from the offset specified by 6714cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// Offset. This returns the value, which is of type ToType. 6724cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// 6734cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// This happens when we are converting an "integer union" to a single 6744cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// integer scalar, or when we are converting a "vector union" to a vector with 6754cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// insert/extractelement instructions. 6764cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// 6774cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// Offset is an offset from the original alloca, in bits that need to be 6784cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// shifted to the right. 6794cc576bc5ea27951f3bb15ccefbe483293bf8eafChris LattnerValue *ConvertToScalarInfo:: 680db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris LattnerConvertScalar_ExtractValue(Value *FromVal, Type *ToType, 6814cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t Offset, IRBuilder<> &Builder) { 6824cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If the load is of the whole new alloca, no conversion is needed. 683db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *FromType = FromVal->getType(); 684be0761c8202405cdd33f1103d262c0aa97895a8eMon P Wang if (FromType == ToType && Offset == 0) 6854cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return FromVal; 6864cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 6874cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If the result alloca is a vector type, this is either an element 6884cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // access or a bitcast to another vector type of the same size. 689db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner if (VectorType *VTy = dyn_cast<VectorType>(FromType)) { 6900398d6135daef709f80837e457a75dc2e1c2aab7Cameron Zwarich unsigned FromTypeSize = TD.getTypeAllocSize(FromType); 6919827b78b51f285e90c2b1e5add9b28d10c88595cCameron Zwarich unsigned ToTypeSize = TD.getTypeAllocSize(ToType); 692446d95224b35b0fef06200b950d45839f1d5f262Cameron Zwarich if (FromTypeSize == ToTypeSize) 693a9390a4d5f5d568059a80970d22194b165d097a7Benjamin Kramer return Builder.CreateBitCast(FromVal, ToType); 6944cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 6954cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Otherwise it must be an element access. 6964cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner unsigned Elt = 0; 6974cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (Offset) { 6984cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner unsigned EltSize = TD.getTypeAllocSizeInBits(VTy->getElementType()); 6994cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Elt = Offset/EltSize; 7004cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner assert(EltSize*Elt == Offset && "Invalid modulus in validity checking"); 701b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson } 7024cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Return the element extracted out of it. 703a9390a4d5f5d568059a80970d22194b165d097a7Benjamin Kramer Value *V = Builder.CreateExtractElement(FromVal, Builder.getInt32(Elt)); 7044cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (V->getType() != ToType) 705a9390a4d5f5d568059a80970d22194b165d097a7Benjamin Kramer V = Builder.CreateBitCast(V, ToType); 7064cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return V; 7074cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 7086974302e3ff20746268721959efed807c7711bfcBob Wilson 7094cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If ToType is a first class aggregate, extract out each of the pieces and 7104cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // use insertvalue's to form the FCA. 711db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner if (StructType *ST = dyn_cast<StructType>(ToType)) { 7124cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner const StructLayout &Layout = *TD.getStructLayout(ST); 7134cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *Res = UndefValue::get(ST); 7144cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner for (unsigned i = 0, e = ST->getNumElements(); i != e; ++i) { 7154cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *Elt = ConvertScalar_ExtractValue(FromVal, ST->getElementType(i), 7164cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Offset+Layout.getElementOffsetInBits(i), 7174cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Builder); 718a9390a4d5f5d568059a80970d22194b165d097a7Benjamin Kramer Res = Builder.CreateInsertValue(Res, Elt, i); 7194cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 7204cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return Res; 7214cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 7226974302e3ff20746268721959efed807c7711bfcBob Wilson 723db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner if (ArrayType *AT = dyn_cast<ArrayType>(ToType)) { 7244cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t EltSize = TD.getTypeAllocSizeInBits(AT->getElementType()); 7254cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *Res = UndefValue::get(AT); 7264cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner for (unsigned i = 0, e = AT->getNumElements(); i != e; ++i) { 7274cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *Elt = ConvertScalar_ExtractValue(FromVal, AT->getElementType(), 7284cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Offset+i*EltSize, Builder); 729a9390a4d5f5d568059a80970d22194b165d097a7Benjamin Kramer Res = Builder.CreateInsertValue(Res, Elt, i); 7304cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 7314cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return Res; 732b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson } 7332674089cefe519195e00bdf879647438cfb1cb0fDaniel Dunbar 7344cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Otherwise, this must be a union that was converted to an integer value. 735db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner IntegerType *NTy = cast<IntegerType>(FromVal->getType()); 736b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson 7374cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If this is a big-endian system and the load is narrower than the 7384cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // full alloca type, we need to do a shift to get the right bits. 7394cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner int ShAmt = 0; 7404cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (TD.isBigEndian()) { 7414cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // On big-endian machines, the lowest bit is stored at the bit offset 7424cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // from the pointer given by getTypeStoreSizeInBits. This matters for 7434cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // integers with a bitwidth that is not a multiple of 8. 7444cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner ShAmt = TD.getTypeStoreSizeInBits(NTy) - 7454cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner TD.getTypeStoreSizeInBits(ToType) - Offset; 746b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson } else { 7474cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner ShAmt = Offset; 748b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson } 749b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson 7504cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Note: we support negative bitwidths (with shl) which are not defined. 7514cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // We do this to support (f.e.) loads off the end of a structure where 7524cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // only some bits are used. 7534cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (ShAmt > 0 && (unsigned)ShAmt < NTy->getBitWidth()) 7544cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner FromVal = Builder.CreateLShr(FromVal, 755a9390a4d5f5d568059a80970d22194b165d097a7Benjamin Kramer ConstantInt::get(FromVal->getType(), ShAmt)); 7564cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner else if (ShAmt < 0 && (unsigned)-ShAmt < NTy->getBitWidth()) 7576974302e3ff20746268721959efed807c7711bfcBob Wilson FromVal = Builder.CreateShl(FromVal, 758a9390a4d5f5d568059a80970d22194b165d097a7Benjamin Kramer ConstantInt::get(FromVal->getType(), -ShAmt)); 759b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson 7604cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Finally, unconditionally truncate the integer to the right width. 7614cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner unsigned LIBitWidth = TD.getTypeSizeInBits(ToType); 7624cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (LIBitWidth < NTy->getBitWidth()) 7634cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner FromVal = 7646974302e3ff20746268721959efed807c7711bfcBob Wilson Builder.CreateTrunc(FromVal, IntegerType::get(FromVal->getContext(), 765a9390a4d5f5d568059a80970d22194b165d097a7Benjamin Kramer LIBitWidth)); 7664cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner else if (LIBitWidth > NTy->getBitWidth()) 7674cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner FromVal = 7686974302e3ff20746268721959efed807c7711bfcBob Wilson Builder.CreateZExt(FromVal, IntegerType::get(FromVal->getContext(), 769a9390a4d5f5d568059a80970d22194b165d097a7Benjamin Kramer LIBitWidth)); 7704cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 7714cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If the result is an integer, this is a trunc or bitcast. 7724cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (ToType->isIntegerTy()) { 7734cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Should be done. 7744cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } else if (ToType->isFloatingPointTy() || ToType->isVectorTy()) { 7754cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Just do a bitcast, we know the sizes match up. 776a9390a4d5f5d568059a80970d22194b165d097a7Benjamin Kramer FromVal = Builder.CreateBitCast(FromVal, ToType); 7774cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } else { 7784cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Otherwise must be a pointer. 779a9390a4d5f5d568059a80970d22194b165d097a7Benjamin Kramer FromVal = Builder.CreateIntToPtr(FromVal, ToType); 780372dda8881c7a32a6f5ce0f76a713e3a9ef46ea1Chris Lattner } 7814cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner assert(FromVal->getType() == ToType && "Didn't convert right?"); 7824cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return FromVal; 783372dda8881c7a32a6f5ce0f76a713e3a9ef46ea1Chris Lattner} 784372dda8881c7a32a6f5ce0f76a713e3a9ef46ea1Chris Lattner 7854cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// ConvertScalar_InsertValue - Insert the value "SV" into the existing integer 7864cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// or vector value "Old" at the offset specified by Offset. 7874cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// 7884cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// This happens when we are converting an "integer union" to a 7894cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// single integer scalar, or when we are converting a "vector union" to a 7904cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// vector with insert/extractelement instructions. 7914cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// 7924cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// Offset is an offset from the original alloca, in bits that need to be 7934cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// shifted to the right. 7944cc576bc5ea27951f3bb15ccefbe483293bf8eafChris LattnerValue *ConvertToScalarInfo:: 7954cc576bc5ea27951f3bb15ccefbe483293bf8eafChris LattnerConvertScalar_InsertValue(Value *SV, Value *Old, 7964cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t Offset, IRBuilder<> &Builder) { 7974cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Convert the stored type to the actual type, shift it left to insert 7984cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // then 'or' into place. 799db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *AllocaType = Old->getType(); 8004cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner LLVMContext &Context = Old->getContext(); 8012674089cefe519195e00bdf879647438cfb1cb0fDaniel Dunbar 802db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner if (VectorType *VTy = dyn_cast<VectorType>(AllocaType)) { 8034cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t VecSize = TD.getTypeAllocSizeInBits(VTy); 8044cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t ValSize = TD.getTypeAllocSizeInBits(SV->getType()); 8056974302e3ff20746268721959efed807c7711bfcBob Wilson 8064cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Changing the whole vector with memset or with an access of a different 8074cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // vector type? 808446d95224b35b0fef06200b950d45839f1d5f262Cameron Zwarich if (ValSize == VecSize) 809a9390a4d5f5d568059a80970d22194b165d097a7Benjamin Kramer return Builder.CreateBitCast(SV, AllocaType); 810b2fd770136b92637c5f084b743eab29f910288d5Cameron Zwarich 8114cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Must be an element insertion. 81290747e34e6ca7162eaf8dde032649071045f161dCameron Zwarich Type *EltTy = VTy->getElementType(); 81390747e34e6ca7162eaf8dde032649071045f161dCameron Zwarich if (SV->getType() != EltTy) 81490747e34e6ca7162eaf8dde032649071045f161dCameron Zwarich SV = Builder.CreateBitCast(SV, EltTy); 81590747e34e6ca7162eaf8dde032649071045f161dCameron Zwarich uint64_t EltSize = TD.getTypeAllocSizeInBits(EltTy); 8164cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner unsigned Elt = Offset/EltSize; 817a9390a4d5f5d568059a80970d22194b165d097a7Benjamin Kramer return Builder.CreateInsertElement(Old, SV, Builder.getInt32(Elt)); 818b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson } 8196974302e3ff20746268721959efed807c7711bfcBob Wilson 8204cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If SV is a first-class aggregate value, insert each value recursively. 821db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner if (StructType *ST = dyn_cast<StructType>(SV->getType())) { 8224cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner const StructLayout &Layout = *TD.getStructLayout(ST); 8234cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner for (unsigned i = 0, e = ST->getNumElements(); i != e; ++i) { 824a9390a4d5f5d568059a80970d22194b165d097a7Benjamin Kramer Value *Elt = Builder.CreateExtractValue(SV, i); 8256974302e3ff20746268721959efed807c7711bfcBob Wilson Old = ConvertScalar_InsertValue(Elt, Old, 8264cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Offset+Layout.getElementOffsetInBits(i), 8274cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Builder); 8284cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 8294cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return Old; 8304cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 8316974302e3ff20746268721959efed807c7711bfcBob Wilson 832db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner if (ArrayType *AT = dyn_cast<ArrayType>(SV->getType())) { 8334cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t EltSize = TD.getTypeAllocSizeInBits(AT->getElementType()); 8344cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner for (unsigned i = 0, e = AT->getNumElements(); i != e; ++i) { 835a9390a4d5f5d568059a80970d22194b165d097a7Benjamin Kramer Value *Elt = Builder.CreateExtractValue(SV, i); 8364cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Old = ConvertScalar_InsertValue(Elt, Old, Offset+i*EltSize, Builder); 8374cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 8384cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return Old; 8394cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 8404cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 8414cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If SV is a float, convert it to the appropriate integer type. 8424cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If it is a pointer, do the same. 8434cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner unsigned SrcWidth = TD.getTypeSizeInBits(SV->getType()); 8444cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner unsigned DestWidth = TD.getTypeSizeInBits(AllocaType); 8454cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner unsigned SrcStoreWidth = TD.getTypeStoreSizeInBits(SV->getType()); 8464cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner unsigned DestStoreWidth = TD.getTypeStoreSizeInBits(AllocaType); 8474cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (SV->getType()->isFloatingPointTy() || SV->getType()->isVectorTy()) 848a9390a4d5f5d568059a80970d22194b165d097a7Benjamin Kramer SV = Builder.CreateBitCast(SV, IntegerType::get(SV->getContext(),SrcWidth)); 8494cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner else if (SV->getType()->isPointerTy()) 850a9390a4d5f5d568059a80970d22194b165d097a7Benjamin Kramer SV = Builder.CreatePtrToInt(SV, TD.getIntPtrType(SV->getContext())); 8514cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 8524cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Zero extend or truncate the value if needed. 8534cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (SV->getType() != AllocaType) { 8544cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (SV->getType()->getPrimitiveSizeInBits() < 8554cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner AllocaType->getPrimitiveSizeInBits()) 856a9390a4d5f5d568059a80970d22194b165d097a7Benjamin Kramer SV = Builder.CreateZExt(SV, AllocaType); 8574cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner else { 8584cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Truncation may be needed if storing more than the alloca can hold 8594cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // (undefined behavior). 860a9390a4d5f5d568059a80970d22194b165d097a7Benjamin Kramer SV = Builder.CreateTrunc(SV, AllocaType); 8614cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner SrcWidth = DestWidth; 8624cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner SrcStoreWidth = DestStoreWidth; 8634cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 8644cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 8654cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 8664cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If this is a big-endian system and the store is narrower than the 8674cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // full alloca type, we need to do a shift to get the right bits. 8684cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner int ShAmt = 0; 8694cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (TD.isBigEndian()) { 8704cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // On big-endian machines, the lowest bit is stored at the bit offset 8714cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // from the pointer given by getTypeStoreSizeInBits. This matters for 8724cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // integers with a bitwidth that is not a multiple of 8. 8734cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner ShAmt = DestStoreWidth - SrcStoreWidth - Offset; 8744cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } else { 8754cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner ShAmt = Offset; 8764cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 8774cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 8784cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Note: we support negative bitwidths (with shr) which are not defined. 8794cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // We do this to support (f.e.) stores off the end of a structure where 8804cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // only some bits in the structure are set. 8814cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner APInt Mask(APInt::getLowBitsSet(DestWidth, SrcWidth)); 8824cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (ShAmt > 0 && (unsigned)ShAmt < DestWidth) { 883a9390a4d5f5d568059a80970d22194b165d097a7Benjamin Kramer SV = Builder.CreateShl(SV, ConstantInt::get(SV->getType(), ShAmt)); 8844cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Mask <<= ShAmt; 8854cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } else if (ShAmt < 0 && (unsigned)-ShAmt < DestWidth) { 886a9390a4d5f5d568059a80970d22194b165d097a7Benjamin Kramer SV = Builder.CreateLShr(SV, ConstantInt::get(SV->getType(), -ShAmt)); 8874cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Mask = Mask.lshr(-ShAmt); 8884cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 8894cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 8904cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Mask out the bits we are about to insert from the old value, and or 8914cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // in the new bits. 8924cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (SrcWidth != DestWidth) { 8934cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner assert(DestWidth > SrcWidth); 8944cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Old = Builder.CreateAnd(Old, ConstantInt::get(Context, ~Mask), "mask"); 8954cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner SV = Builder.CreateOr(Old, SV, "ins"); 8964cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 8974cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return SV; 898b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson} 899b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson 900b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson 9014cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner//===----------------------------------------------------------------------===// 9024cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner// SRoA Driver 9034cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner//===----------------------------------------------------------------------===// 904b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson 905b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson 9064cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattnerbool SROA::runOnFunction(Function &F) { 9074cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner TD = getAnalysisIfAvailable<TargetData>(); 908b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson 9094cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner bool Changed = performPromotion(F); 910b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson 9114cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // FIXME: ScalarRepl currently depends on TargetData more than it 9124cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // theoretically needs to. It should be refactored in order to support 9134cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // target-independent IR. Until this is done, just skip the actual 9144cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // scalar-replacement portion of this pass. 9154cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (!TD) return Changed; 9164cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 9174cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner while (1) { 9184cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner bool LocalChange = performScalarRepl(F); 9194cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (!LocalChange) break; // No need to repromote if no scalarrepl 9204cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Changed = true; 9214cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner LocalChange = performPromotion(F); 9224cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (!LocalChange) break; // No need to re-scalarrepl if no promotion 9232674089cefe519195e00bdf879647438cfb1cb0fDaniel Dunbar } 9244cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 9254cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return Changed; 926d93afec1dbbb1abb3df55e2e007b5f256d09f84aChris Lattner} 927d93afec1dbbb1abb3df55e2e007b5f256d09f84aChris Lattner 928d0f56132cfa6e25fb9692e84ea12444c86b92ae4Chris Lattnernamespace { 929d0f56132cfa6e25fb9692e84ea12444c86b92ae4Chris Lattnerclass AllocaPromoter : public LoadAndStorePromoter { 930d0f56132cfa6e25fb9692e84ea12444c86b92ae4Chris Lattner AllocaInst *AI; 931231a5ab746ca12000aa57208869a98f78781aa6bDevang Patel DIBuilder *DIB; 9324fd3c5957e6a272b60d6446e745136187d07f812Devang Patel SmallVector<DbgDeclareInst *, 4> DDIs; 9334fd3c5957e6a272b60d6446e745136187d07f812Devang Patel SmallVector<DbgValueInst *, 4> DVIs; 934d0f56132cfa6e25fb9692e84ea12444c86b92ae4Chris Lattnerpublic: 935c827939046670a9800659b83e2048f1d3a79a531Cameron Zwarich AllocaPromoter(const SmallVectorImpl<Instruction*> &Insts, SSAUpdater &S, 936231a5ab746ca12000aa57208869a98f78781aa6bDevang Patel DIBuilder *DB) 9374fd3c5957e6a272b60d6446e745136187d07f812Devang Patel : LoadAndStorePromoter(Insts, S), AI(0), DIB(DB) {} 938e0a1a5ba91df6817f9ffae7af65ed0bda66f7620Chris Lattner 939deaf55f69865bbc997a569c2a689ec5b0fbdefefChris Lattner void run(AllocaInst *AI, const SmallVectorImpl<Instruction*> &Insts) { 940d0f56132cfa6e25fb9692e84ea12444c86b92ae4Chris Lattner // Remember which alloca we're promoting (for isInstInList). 941d0f56132cfa6e25fb9692e84ea12444c86b92ae4Chris Lattner this->AI = AI; 942125ef76934f37e3fdc8ce4a2cc238850d06c5912Rafael Espindola if (MDNode *DebugNode = MDNode::getIfExists(AI->getContext(), AI)) { 9434fd3c5957e6a272b60d6446e745136187d07f812Devang Patel for (Value::use_iterator UI = DebugNode->use_begin(), 9444fd3c5957e6a272b60d6446e745136187d07f812Devang Patel E = DebugNode->use_end(); UI != E; ++UI) 9454fd3c5957e6a272b60d6446e745136187d07f812Devang Patel if (DbgDeclareInst *DDI = dyn_cast<DbgDeclareInst>(*UI)) 9464fd3c5957e6a272b60d6446e745136187d07f812Devang Patel DDIs.push_back(DDI); 9474fd3c5957e6a272b60d6446e745136187d07f812Devang Patel else if (DbgValueInst *DVI = dyn_cast<DbgValueInst>(*UI)) 9484fd3c5957e6a272b60d6446e745136187d07f812Devang Patel DVIs.push_back(DVI); 949125ef76934f37e3fdc8ce4a2cc238850d06c5912Rafael Espindola } 9504fd3c5957e6a272b60d6446e745136187d07f812Devang Patel 951deaf55f69865bbc997a569c2a689ec5b0fbdefefChris Lattner LoadAndStorePromoter::run(Insts); 952d0f56132cfa6e25fb9692e84ea12444c86b92ae4Chris Lattner AI->eraseFromParent(); 9534fd3c5957e6a272b60d6446e745136187d07f812Devang Patel for (SmallVector<DbgDeclareInst *, 4>::iterator I = DDIs.begin(), 9544fd3c5957e6a272b60d6446e745136187d07f812Devang Patel E = DDIs.end(); I != E; ++I) { 9554fd3c5957e6a272b60d6446e745136187d07f812Devang Patel DbgDeclareInst *DDI = *I; 956231a5ab746ca12000aa57208869a98f78781aa6bDevang Patel DDI->eraseFromParent(); 9574fd3c5957e6a272b60d6446e745136187d07f812Devang Patel } 9584fd3c5957e6a272b60d6446e745136187d07f812Devang Patel for (SmallVector<DbgValueInst *, 4>::iterator I = DVIs.begin(), 9594fd3c5957e6a272b60d6446e745136187d07f812Devang Patel E = DVIs.end(); I != E; ++I) { 9604fd3c5957e6a272b60d6446e745136187d07f812Devang Patel DbgValueInst *DVI = *I; 9614fd3c5957e6a272b60d6446e745136187d07f812Devang Patel DVI->eraseFromParent(); 9624fd3c5957e6a272b60d6446e745136187d07f812Devang Patel } 963e0a1a5ba91df6817f9ffae7af65ed0bda66f7620Chris Lattner } 964e0a1a5ba91df6817f9ffae7af65ed0bda66f7620Chris Lattner 965d0f56132cfa6e25fb9692e84ea12444c86b92ae4Chris Lattner virtual bool isInstInList(Instruction *I, 966d0f56132cfa6e25fb9692e84ea12444c86b92ae4Chris Lattner const SmallVectorImpl<Instruction*> &Insts) const { 967d0f56132cfa6e25fb9692e84ea12444c86b92ae4Chris Lattner if (LoadInst *LI = dyn_cast<LoadInst>(I)) 968d0f56132cfa6e25fb9692e84ea12444c86b92ae4Chris Lattner return LI->getOperand(0) == AI; 969d0f56132cfa6e25fb9692e84ea12444c86b92ae4Chris Lattner return cast<StoreInst>(I)->getPointerOperand() == AI; 970e0a1a5ba91df6817f9ffae7af65ed0bda66f7620Chris Lattner } 971231a5ab746ca12000aa57208869a98f78781aa6bDevang Patel 9724fd3c5957e6a272b60d6446e745136187d07f812Devang Patel virtual void updateDebugInfo(Instruction *Inst) const { 9734fd3c5957e6a272b60d6446e745136187d07f812Devang Patel for (SmallVector<DbgDeclareInst *, 4>::const_iterator I = DDIs.begin(), 9744fd3c5957e6a272b60d6446e745136187d07f812Devang Patel E = DDIs.end(); I != E; ++I) { 9754fd3c5957e6a272b60d6446e745136187d07f812Devang Patel DbgDeclareInst *DDI = *I; 9764fd3c5957e6a272b60d6446e745136187d07f812Devang Patel if (StoreInst *SI = dyn_cast<StoreInst>(Inst)) 9774fd3c5957e6a272b60d6446e745136187d07f812Devang Patel ConvertDebugDeclareToDebugValue(DDI, SI, *DIB); 9784fd3c5957e6a272b60d6446e745136187d07f812Devang Patel else if (LoadInst *LI = dyn_cast<LoadInst>(Inst)) 9794fd3c5957e6a272b60d6446e745136187d07f812Devang Patel ConvertDebugDeclareToDebugValue(DDI, LI, *DIB); 9804fd3c5957e6a272b60d6446e745136187d07f812Devang Patel } 9814fd3c5957e6a272b60d6446e745136187d07f812Devang Patel for (SmallVector<DbgValueInst *, 4>::const_iterator I = DVIs.begin(), 9824fd3c5957e6a272b60d6446e745136187d07f812Devang Patel E = DVIs.end(); I != E; ++I) { 9834fd3c5957e6a272b60d6446e745136187d07f812Devang Patel DbgValueInst *DVI = *I; 9846a1c7796d3966851456b835d69909e3df7f5e966Benjamin Kramer Value *Arg = NULL; 9854fd3c5957e6a272b60d6446e745136187d07f812Devang Patel if (StoreInst *SI = dyn_cast<StoreInst>(Inst)) { 9864fd3c5957e6a272b60d6446e745136187d07f812Devang Patel // If an argument is zero extended then use argument directly. The ZExt 9874fd3c5957e6a272b60d6446e745136187d07f812Devang Patel // may be zapped by an optimization pass in future. 9884fd3c5957e6a272b60d6446e745136187d07f812Devang Patel if (ZExtInst *ZExt = dyn_cast<ZExtInst>(SI->getOperand(0))) 9896a1c7796d3966851456b835d69909e3df7f5e966Benjamin Kramer Arg = dyn_cast<Argument>(ZExt->getOperand(0)); 9904fd3c5957e6a272b60d6446e745136187d07f812Devang Patel if (SExtInst *SExt = dyn_cast<SExtInst>(SI->getOperand(0))) 9916a1c7796d3966851456b835d69909e3df7f5e966Benjamin Kramer Arg = dyn_cast<Argument>(SExt->getOperand(0)); 9926a1c7796d3966851456b835d69909e3df7f5e966Benjamin Kramer if (!Arg) 9936a1c7796d3966851456b835d69909e3df7f5e966Benjamin Kramer Arg = SI->getOperand(0); 9944fd3c5957e6a272b60d6446e745136187d07f812Devang Patel } else if (LoadInst *LI = dyn_cast<LoadInst>(Inst)) { 9956a1c7796d3966851456b835d69909e3df7f5e966Benjamin Kramer Arg = LI->getOperand(0); 9966a1c7796d3966851456b835d69909e3df7f5e966Benjamin Kramer } else { 9976a1c7796d3966851456b835d69909e3df7f5e966Benjamin Kramer continue; 9984fd3c5957e6a272b60d6446e745136187d07f812Devang Patel } 9996a1c7796d3966851456b835d69909e3df7f5e966Benjamin Kramer Instruction *DbgVal = 10006a1c7796d3966851456b835d69909e3df7f5e966Benjamin Kramer DIB->insertDbgValueIntrinsic(Arg, 0, DIVariable(DVI->getVariable()), 10016a1c7796d3966851456b835d69909e3df7f5e966Benjamin Kramer Inst); 10026a1c7796d3966851456b835d69909e3df7f5e966Benjamin Kramer DbgVal->setDebugLoc(DVI->getDebugLoc()); 10034fd3c5957e6a272b60d6446e745136187d07f812Devang Patel } 1004231a5ab746ca12000aa57208869a98f78781aa6bDevang Patel } 1005d0f56132cfa6e25fb9692e84ea12444c86b92ae4Chris Lattner}; 1006d0f56132cfa6e25fb9692e84ea12444c86b92ae4Chris Lattner} // end anon namespace 100778c50b8cd68d266d4ed6f8eca443cf8142a01204Bob Wilson 1008c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner/// isSafeSelectToSpeculate - Select instructions that use an alloca and are 1009c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner/// subsequently loaded can be rewritten to load both input pointers and then 1010c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner/// select between the result, allowing the load of the alloca to be promoted. 1011c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner/// From this: 1012c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner/// %P2 = select i1 %cond, i32* %Alloca, i32* %Other 1013c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner/// %V = load i32* %P2 1014c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner/// to: 1015c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner/// %V1 = load i32* %Alloca -> will be mem2reg'd 1016c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner/// %V2 = load i32* %Other 1017e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner/// %V = select i1 %cond, i32 %V1, i32 %V2 1018c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner/// 1019c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner/// We can do this to a select if its only uses are loads and if the operand to 1020c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner/// the select can be loaded unconditionally. 1021c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattnerstatic bool isSafeSelectToSpeculate(SelectInst *SI, const TargetData *TD) { 1022c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner bool TDerefable = SI->getTrueValue()->isDereferenceablePointer(); 1023c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner bool FDerefable = SI->getFalseValue()->isDereferenceablePointer(); 1024c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner 1025c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner for (Value::use_iterator UI = SI->use_begin(), UE = SI->use_end(); 1026c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner UI != UE; ++UI) { 1027c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner LoadInst *LI = dyn_cast<LoadInst>(*UI); 10282bc3d52b9ab422ee9f7e42a1a4e3b818e623a5f7Eli Friedman if (LI == 0 || !LI->isSimple()) return false; 1029c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner 1030e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // Both operands to the select need to be dereferencable, either absolutely 1031c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner // (e.g. allocas) or at this point because we can see other accesses to it. 1032c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner if (!TDerefable && !isSafeToLoadUnconditionally(SI->getTrueValue(), LI, 1033c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner LI->getAlignment(), TD)) 1034c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner return false; 1035c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner if (!FDerefable && !isSafeToLoadUnconditionally(SI->getFalseValue(), LI, 1036c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner LI->getAlignment(), TD)) 1037c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner return false; 1038c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner } 1039c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner 1040c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner return true; 1041c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner} 1042c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner 1043e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner/// isSafePHIToSpeculate - PHI instructions that use an alloca and are 1044e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner/// subsequently loaded can be rewritten to load both input pointers in the pred 1045e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner/// blocks and then PHI the results, allowing the load of the alloca to be 1046e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner/// promoted. 1047e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner/// From this: 1048e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner/// %P2 = phi [i32* %Alloca, i32* %Other] 1049e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner/// %V = load i32* %P2 1050e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner/// to: 1051e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner/// %V1 = load i32* %Alloca -> will be mem2reg'd 1052e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner/// ... 1053e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner/// %V2 = load i32* %Other 1054e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner/// ... 1055e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner/// %V = phi [i32 %V1, i32 %V2] 1056e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner/// 1057e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner/// We can do this to a select if its only uses are loads and if the operand to 1058e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner/// the select can be loaded unconditionally. 1059e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattnerstatic bool isSafePHIToSpeculate(PHINode *PN, const TargetData *TD) { 1060e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // For now, we can only do this promotion if the load is in the same block as 1061e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // the PHI, and if there are no stores between the phi and load. 1062e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // TODO: Allow recursive phi users. 1063e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // TODO: Allow stores. 1064e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner BasicBlock *BB = PN->getParent(); 1065e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner unsigned MaxAlign = 0; 1066e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner for (Value::use_iterator UI = PN->use_begin(), UE = PN->use_end(); 1067e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner UI != UE; ++UI) { 1068e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner LoadInst *LI = dyn_cast<LoadInst>(*UI); 10692bc3d52b9ab422ee9f7e42a1a4e3b818e623a5f7Eli Friedman if (LI == 0 || !LI->isSimple()) return false; 1070e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner 1071e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // For now we only allow loads in the same block as the PHI. This is a 1072e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // common case that happens when instcombine merges two loads through a PHI. 1073e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner if (LI->getParent() != BB) return false; 1074e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner 1075e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // Ensure that there are no instructions between the PHI and the load that 1076e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // could store. 1077e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner for (BasicBlock::iterator BBI = PN; &*BBI != LI; ++BBI) 1078e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner if (BBI->mayWriteToMemory()) 1079e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner return false; 1080e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner 1081e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner MaxAlign = std::max(MaxAlign, LI->getAlignment()); 1082e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner } 1083e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner 1084e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // Okay, we know that we have one or more loads in the same block as the PHI. 1085e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // We can transform this if it is safe to push the loads into the predecessor 1086e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // blocks. The only thing to watch out for is that we can't put a possibly 1087e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // trapping load in the predecessor if it is a critical edge. 1088e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i) { 1089e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner BasicBlock *Pred = PN->getIncomingBlock(i); 1090d102a03b36fb522899cefc31a396c9793b929cf6Eli Friedman Value *InVal = PN->getIncomingValue(i); 1091d102a03b36fb522899cefc31a396c9793b929cf6Eli Friedman 1092d102a03b36fb522899cefc31a396c9793b929cf6Eli Friedman // If the terminator of the predecessor has side-effects (an invoke), 1093d102a03b36fb522899cefc31a396c9793b929cf6Eli Friedman // there is no safe place to put a load in the predecessor. 1094d102a03b36fb522899cefc31a396c9793b929cf6Eli Friedman if (Pred->getTerminator()->mayHaveSideEffects()) 1095d102a03b36fb522899cefc31a396c9793b929cf6Eli Friedman return false; 1096d102a03b36fb522899cefc31a396c9793b929cf6Eli Friedman 1097d102a03b36fb522899cefc31a396c9793b929cf6Eli Friedman // If the value is produced by the terminator of the predecessor 1098d102a03b36fb522899cefc31a396c9793b929cf6Eli Friedman // (an invoke), there is no valid place to put a load in the predecessor. 1099d102a03b36fb522899cefc31a396c9793b929cf6Eli Friedman if (Pred->getTerminator() == InVal) 1100d102a03b36fb522899cefc31a396c9793b929cf6Eli Friedman return false; 1101e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner 1102e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // If the predecessor has a single successor, then the edge isn't critical. 1103e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner if (Pred->getTerminator()->getNumSuccessors() == 1) 1104e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner continue; 1105e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner 1106e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // If this pointer is always safe to load, or if we can prove that there is 1107e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // already a load in the block, then we can move the load to the pred block. 1108e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner if (InVal->isDereferenceablePointer() || 1109e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner isSafeToLoadUnconditionally(InVal, Pred->getTerminator(), MaxAlign, TD)) 1110e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner continue; 1111e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner 1112e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner return false; 1113e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner } 1114e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner 1115e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner return true; 1116e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner} 1117e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner 1118c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner 1119c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner/// tryToMakeAllocaBePromotable - This returns true if the alloca only has 1120c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner/// direct (non-volatile) loads and stores to it. If the alloca is close but 1121c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner/// not quite there, this will transform the code to allow promotion. As such, 1122c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner/// it is a non-pure predicate. 1123c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattnerstatic bool tryToMakeAllocaBePromotable(AllocaInst *AI, const TargetData *TD) { 1124c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner SetVector<Instruction*, SmallVector<Instruction*, 4>, 1125c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner SmallPtrSet<Instruction*, 4> > InstsToRewrite; 1126c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner 1127c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner for (Value::use_iterator UI = AI->use_begin(), UE = AI->use_end(); 1128c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner UI != UE; ++UI) { 1129c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner User *U = *UI; 1130c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner if (LoadInst *LI = dyn_cast<LoadInst>(U)) { 11312bc3d52b9ab422ee9f7e42a1a4e3b818e623a5f7Eli Friedman if (!LI->isSimple()) 1132c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner return false; 1133c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner continue; 1134c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner } 1135c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner 1136c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner if (StoreInst *SI = dyn_cast<StoreInst>(U)) { 11372bc3d52b9ab422ee9f7e42a1a4e3b818e623a5f7Eli Friedman if (SI->getOperand(0) == AI || !SI->isSimple()) 1138c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner return false; // Don't allow a store OF the AI, only INTO the AI. 1139c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner continue; 1140c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner } 1141c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner 1142c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner if (SelectInst *SI = dyn_cast<SelectInst>(U)) { 1143c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner // If the condition being selected on is a constant, fold the select, yes 1144c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner // this does (rarely) happen early on. 1145c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner if (ConstantInt *CI = dyn_cast<ConstantInt>(SI->getCondition())) { 1146c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner Value *Result = SI->getOperand(1+CI->isZero()); 1147c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner SI->replaceAllUsesWith(Result); 1148c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner SI->eraseFromParent(); 1149c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner 1150c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner // This is very rare and we just scrambled the use list of AI, start 1151c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner // over completely. 1152c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner return tryToMakeAllocaBePromotable(AI, TD); 1153c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner } 1154c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner 1155c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner // If it is safe to turn "load (select c, AI, ptr)" into a select of two 1156c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner // loads, then we can transform this by rewriting the select. 1157c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner if (!isSafeSelectToSpeculate(SI, TD)) 1158c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner return false; 1159c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner 1160c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner InstsToRewrite.insert(SI); 1161c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner continue; 1162c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner } 1163c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner 1164e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner if (PHINode *PN = dyn_cast<PHINode>(U)) { 1165e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner if (PN->use_empty()) { // Dead PHIs can be stripped. 1166e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner InstsToRewrite.insert(PN); 1167e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner continue; 1168e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner } 1169e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner 1170e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // If it is safe to turn "load (phi [AI, ptr, ...])" into a PHI of loads 1171e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // in the pred blocks, then we can transform this by rewriting the PHI. 1172e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner if (!isSafePHIToSpeculate(PN, TD)) 1173e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner return false; 1174e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner 1175e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner InstsToRewrite.insert(PN); 1176e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner continue; 1177e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner } 1178e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner 11795a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky if (BitCastInst *BCI = dyn_cast<BitCastInst>(U)) { 11805a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky if (onlyUsedByLifetimeMarkers(BCI)) { 11815a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky InstsToRewrite.insert(BCI); 11825a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky continue; 11835a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky } 11845a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky } 11855a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky 1186c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner return false; 1187c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner } 1188c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner 1189c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner // If there are no instructions to rewrite, then all uses are load/stores and 1190c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner // we're done! 1191c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner if (InstsToRewrite.empty()) 1192c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner return true; 1193c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner 1194c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner // If we have instructions that need to be rewritten for this to be promotable 1195c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner // take care of it now. 1196c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner for (unsigned i = 0, e = InstsToRewrite.size(); i != e; ++i) { 11975a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky if (BitCastInst *BCI = dyn_cast<BitCastInst>(InstsToRewrite[i])) { 11985a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky // This could only be a bitcast used by nothing but lifetime intrinsics. 11995a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky for (BitCastInst::use_iterator I = BCI->use_begin(), E = BCI->use_end(); 12005a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky I != E;) { 12015a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky Use &U = I.getUse(); 12025a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky ++I; 12035a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky cast<Instruction>(U.getUser())->eraseFromParent(); 12045a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky } 12055a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky BCI->eraseFromParent(); 12065a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky continue; 12075a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky } 12085a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky 1209e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner if (SelectInst *SI = dyn_cast<SelectInst>(InstsToRewrite[i])) { 1210e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // Selects in InstsToRewrite only have load uses. Rewrite each as two 1211e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // loads with a new select. 1212e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner while (!SI->use_empty()) { 1213e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner LoadInst *LI = cast<LoadInst>(SI->use_back()); 1214c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner 1215e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner IRBuilder<> Builder(LI); 1216e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner LoadInst *TrueLoad = 1217e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner Builder.CreateLoad(SI->getTrueValue(), LI->getName()+".t"); 1218e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner LoadInst *FalseLoad = 1219394d1f1948c1b5c9e902059104b08a4837dfbbeeNick Lewycky Builder.CreateLoad(SI->getFalseValue(), LI->getName()+".f"); 1220e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner 1221e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // Transfer alignment and TBAA info if present. 1222e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner TrueLoad->setAlignment(LI->getAlignment()); 1223e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner FalseLoad->setAlignment(LI->getAlignment()); 1224e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner if (MDNode *Tag = LI->getMetadata(LLVMContext::MD_tbaa)) { 1225e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner TrueLoad->setMetadata(LLVMContext::MD_tbaa, Tag); 1226e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner FalseLoad->setMetadata(LLVMContext::MD_tbaa, Tag); 1227e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner } 1228e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner 1229e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner Value *V = Builder.CreateSelect(SI->getCondition(), TrueLoad, FalseLoad); 1230e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner V->takeName(LI); 1231e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner LI->replaceAllUsesWith(V); 1232e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner LI->eraseFromParent(); 1233c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner } 1234e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner 1235e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // Now that all the loads are gone, the select is gone too. 1236e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner SI->eraseFromParent(); 1237e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner continue; 1238e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner } 1239e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner 1240e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // Otherwise, we have a PHI node which allows us to push the loads into the 1241e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // predecessors. 1242e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner PHINode *PN = cast<PHINode>(InstsToRewrite[i]); 1243e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner if (PN->use_empty()) { 1244e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner PN->eraseFromParent(); 1245e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner continue; 1246e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner } 1247e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner 1248db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *LoadTy = cast<PointerType>(PN->getType())->getElementType(); 12493ecfc861b4365f341c5c969b40e1afccde676e6fJay Foad PHINode *NewPN = PHINode::Create(LoadTy, PN->getNumIncomingValues(), 12503ecfc861b4365f341c5c969b40e1afccde676e6fJay Foad PN->getName()+".ld", PN); 1251e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner 1252e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // Get the TBAA tag and alignment to use from one of the loads. It doesn't 1253e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // matter which one we get and if any differ, it doesn't matter. 1254e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner LoadInst *SomeLoad = cast<LoadInst>(PN->use_back()); 1255e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner MDNode *TBAATag = SomeLoad->getMetadata(LLVMContext::MD_tbaa); 1256e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner unsigned Align = SomeLoad->getAlignment(); 1257e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner 1258e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // Rewrite all loads of the PN to use the new PHI. 1259e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner while (!PN->use_empty()) { 1260e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner LoadInst *LI = cast<LoadInst>(PN->use_back()); 1261e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner LI->replaceAllUsesWith(NewPN); 1262c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner LI->eraseFromParent(); 1263c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner } 1264c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner 1265e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // Inject loads into all of the pred blocks. Keep track of which blocks we 1266e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner // insert them into in case we have multiple edges from the same block. 1267e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner DenseMap<BasicBlock*, LoadInst*> InsertedLoads; 1268e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner 1269e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i) { 1270e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner BasicBlock *Pred = PN->getIncomingBlock(i); 1271e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner LoadInst *&Load = InsertedLoads[Pred]; 1272e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner if (Load == 0) { 1273e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner Load = new LoadInst(PN->getIncomingValue(i), 1274e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner PN->getName() + "." + Pred->getName(), 1275e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner Pred->getTerminator()); 1276e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner Load->setAlignment(Align); 1277e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner if (TBAATag) Load->setMetadata(LLVMContext::MD_tbaa, TBAATag); 1278e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner } 1279e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner 1280e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner NewPN->addIncoming(Load, Pred); 1281e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner } 1282e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner 1283e3357863aaabe297c5fa819d083f2308ebb5f2c2Chris Lattner PN->eraseFromParent(); 1284c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner } 1285c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner 1286c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner ++NumAdjusted; 1287c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner return true; 1288c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner} 1289c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner 12904cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattnerbool SROA::performPromotion(Function &F) { 12914cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner std::vector<AllocaInst*> Allocas; 1292e0a1a5ba91df6817f9ffae7af65ed0bda66f7620Chris Lattner DominatorTree *DT = 0; 1293b1686c32fc694636cbf15a59b23b2a741b65ecf4Cameron Zwarich if (HasDomTree) 1294e0a1a5ba91df6817f9ffae7af65ed0bda66f7620Chris Lattner DT = &getAnalysis<DominatorTree>(); 1295b742defa0a8f3e477c3ed641da49aab276937556Bob Wilson 12964cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner BasicBlock &BB = F.getEntryBlock(); // Get the entry node for the function 1297231a5ab746ca12000aa57208869a98f78781aa6bDevang Patel DIBuilder DIB(*F.getParent()); 12984cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner bool Changed = false; 1299deaf55f69865bbc997a569c2a689ec5b0fbdefefChris Lattner SmallVector<Instruction*, 64> Insts; 13004cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner while (1) { 13014cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Allocas.clear(); 13024cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 13034cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Find allocas that are safe to promote, by looking at all instructions in 13044cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // the entry node 13054cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner for (BasicBlock::iterator I = BB.begin(), E = --BB.end(); I != E; ++I) 13064cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (AllocaInst *AI = dyn_cast<AllocaInst>(I)) // Is it an alloca? 1307c87c50a39c1bc27437352feee0f6aba2d50fa1b5Chris Lattner if (tryToMakeAllocaBePromotable(AI, TD)) 13084cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Allocas.push_back(AI); 13094cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 13104cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (Allocas.empty()) break; 13114cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 1312b1686c32fc694636cbf15a59b23b2a741b65ecf4Cameron Zwarich if (HasDomTree) 1313419e8a62997987e0509efe721c1ea81ac29f09f3Cameron Zwarich PromoteMemToReg(Allocas, *DT); 1314e0a1a5ba91df6817f9ffae7af65ed0bda66f7620Chris Lattner else { 1315e0a1a5ba91df6817f9ffae7af65ed0bda66f7620Chris Lattner SSAUpdater SSA; 1316deaf55f69865bbc997a569c2a689ec5b0fbdefefChris Lattner for (unsigned i = 0, e = Allocas.size(); i != e; ++i) { 1317deaf55f69865bbc997a569c2a689ec5b0fbdefefChris Lattner AllocaInst *AI = Allocas[i]; 1318deaf55f69865bbc997a569c2a689ec5b0fbdefefChris Lattner 1319deaf55f69865bbc997a569c2a689ec5b0fbdefefChris Lattner // Build list of instructions to promote. 1320deaf55f69865bbc997a569c2a689ec5b0fbdefefChris Lattner for (Value::use_iterator UI = AI->use_begin(), E = AI->use_end(); 1321deaf55f69865bbc997a569c2a689ec5b0fbdefefChris Lattner UI != E; ++UI) 1322deaf55f69865bbc997a569c2a689ec5b0fbdefefChris Lattner Insts.push_back(cast<Instruction>(*UI)); 1323231a5ab746ca12000aa57208869a98f78781aa6bDevang Patel AllocaPromoter(Insts, SSA, &DIB).run(AI, Insts); 1324deaf55f69865bbc997a569c2a689ec5b0fbdefefChris Lattner Insts.clear(); 1325deaf55f69865bbc997a569c2a689ec5b0fbdefefChris Lattner } 1326e0a1a5ba91df6817f9ffae7af65ed0bda66f7620Chris Lattner } 13274cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner NumPromoted += Allocas.size(); 13284cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Changed = true; 13294cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 13304cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 13314cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return Changed; 13324cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner} 13334cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 13344cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 13354cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// ShouldAttemptScalarRepl - Decide if an alloca is a good candidate for 13364cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// SROA. It must be a struct or array type with a small number of elements. 13374cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattnerstatic bool ShouldAttemptScalarRepl(AllocaInst *AI) { 1338db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *T = AI->getAllocatedType(); 13394cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Do not promote any struct into more than 32 separate vars. 1340db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner if (StructType *ST = dyn_cast<StructType>(T)) 13414cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return ST->getNumElements() <= 32; 13424cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Arrays are much less likely to be safe for SROA; only consider 13434cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // them if they are very small. 1344db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner if (ArrayType *AT = dyn_cast<ArrayType>(T)) 13454cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return AT->getNumElements() <= 8; 13464cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return false; 13474cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner} 13484cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 13494cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 13504cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner// performScalarRepl - This algorithm is a simple worklist driven algorithm, 13519174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky// which runs on all of the alloca instructions in the function, removing them 13529174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky// if they are only used by getelementptr instructions. 13534cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner// 13544cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattnerbool SROA::performScalarRepl(Function &F) { 13554cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner std::vector<AllocaInst*> WorkList; 13564cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 13574cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Scan the entry basic block, adding allocas to the worklist. 13584cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner BasicBlock &BB = F.getEntryBlock(); 13594cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner for (BasicBlock::iterator I = BB.begin(), E = BB.end(); I != E; ++I) 13604cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (AllocaInst *A = dyn_cast<AllocaInst>(I)) 13614cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner WorkList.push_back(A); 13624cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 13634cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Process the worklist 13644cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner bool Changed = false; 13654cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner while (!WorkList.empty()) { 13664cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner AllocaInst *AI = WorkList.back(); 13674cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner WorkList.pop_back(); 13686974302e3ff20746268721959efed807c7711bfcBob Wilson 13694cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Handle dead allocas trivially. These can be formed by SROA'ing arrays 13704cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // with unused elements. 13714cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (AI->use_empty()) { 13724cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner AI->eraseFromParent(); 13734cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Changed = true; 13744cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner continue; 1375d93afec1dbbb1abb3df55e2e007b5f256d09f84aChris Lattner } 13764cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 13774cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If this alloca is impossible for us to promote, reject it early. 13784cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (AI->isArrayAllocation() || !AI->getAllocatedType()->isSized()) 13794cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner continue; 13806974302e3ff20746268721959efed807c7711bfcBob Wilson 13814cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Check to see if this allocation is only modified by a memcpy/memmove from 13824cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // a constant global. If this is the case, we can change all users to use 13834cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // the constant global instead. This is commonly produced by the CFE by 13844cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // constructs like "void foo() { int A[] = {1,2,3,4,5,6,7,8,9...}; }" if 'A' 13854cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // is only subsequently read. 13869174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky SmallVector<Instruction *, 4> ToDelete; 13879174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky if (MemTransferInst *Copy = isOnlyCopiedFromConstantGlobal(AI, ToDelete)) { 13884cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner DEBUG(dbgs() << "Found alloca equal to global: " << *AI << '\n'); 13899174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky DEBUG(dbgs() << " memcpy = " << *Copy << '\n'); 13909174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky for (unsigned i = 0, e = ToDelete.size(); i != e; ++i) 13919174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky ToDelete[i]->eraseFromParent(); 13929174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky Constant *TheSrc = cast<Constant>(Copy->getSource()); 13934cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner AI->replaceAllUsesWith(ConstantExpr::getBitCast(TheSrc, AI->getType())); 13949174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky Copy->eraseFromParent(); // Don't mutate the global. 13954cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner AI->eraseFromParent(); 13964cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner ++NumGlobals; 13974cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Changed = true; 13984cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner continue; 13994cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 14006974302e3ff20746268721959efed807c7711bfcBob Wilson 14014cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Check to see if we can perform the core SROA transformation. We cannot 14024cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // transform the allocation instruction if it is an array allocation 14034cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // (allocations OF arrays are ok though), and an allocation of a scalar 14044cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // value cannot be decomposed at all. 14054cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t AllocaSize = TD->getTypeAllocSize(AI->getAllocatedType()); 140644118f0e25c25fedda1ccdd6a72f072c0b5c96e7Dan Gohman 14074cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Do not promote [0 x %struct]. 14084cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (AllocaSize == 0) continue; 14096974302e3ff20746268721959efed807c7711bfcBob Wilson 14104cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Do not promote any struct whose size is too big. 14114cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (AllocaSize > SRThreshold) continue; 14126974302e3ff20746268721959efed807c7711bfcBob Wilson 14134cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If the alloca looks like a good candidate for scalar replacement, and if 14144cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // all its users can be transformed, then split up the aggregate into its 14154cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // separate elements. 14164cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (ShouldAttemptScalarRepl(AI) && isSafeAllocaToScalarRepl(AI)) { 14174cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner DoScalarReplacement(AI, WorkList); 14184cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Changed = true; 14194cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner continue; 142020adc9dc4650313f017b27d9818eb2176238113dMon P Wang } 14214cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 14224cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If we can turn this aggregate value (potentially with casts) into a 14234cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // simple scalar value that can be mem2reg'd into a register value. 14244cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // IsNotTrivial tracks whether this is something that mem2reg could have 14254cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // promoted itself. If so, we don't want to transform it needlessly. Note 14264cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // that we can't just check based on the type: the alloca may be of an i32 14274cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // but that has pointer arithmetic to set byte 3 of it or something. 14284cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (AllocaInst *NewAI = 14294cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner ConvertToScalarInfo((unsigned)AllocaSize, *TD).TryConvert(AI)) { 14304cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner NewAI->takeName(AI); 14314cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner AI->eraseFromParent(); 14324cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner ++NumConverted; 14334cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Changed = true; 14344cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner continue; 14356974302e3ff20746268721959efed807c7711bfcBob Wilson } 14366974302e3ff20746268721959efed807c7711bfcBob Wilson 14374cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Otherwise, couldn't process this alloca. 1438372dda8881c7a32a6f5ce0f76a713e3a9ef46ea1Chris Lattner } 14394cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 14404cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return Changed; 1441372dda8881c7a32a6f5ce0f76a713e3a9ef46ea1Chris Lattner} 1442d2fa781169175b827e50953a1d0b7edc6b0c4801Chris Lattner 14434cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// DoScalarReplacement - This alloca satisfied the isSafeAllocaToScalarRepl 14444cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// predicate, do SROA now. 14456974302e3ff20746268721959efed807c7711bfcBob Wilsonvoid SROA::DoScalarReplacement(AllocaInst *AI, 14464cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner std::vector<AllocaInst*> &WorkList) { 14474cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner DEBUG(dbgs() << "Found inst to SROA: " << *AI << '\n'); 14484cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner SmallVector<AllocaInst*, 32> ElementAllocas; 1449db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner if (StructType *ST = dyn_cast<StructType>(AI->getAllocatedType())) { 14504cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner ElementAllocas.reserve(ST->getNumContainedTypes()); 14514cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner for (unsigned i = 0, e = ST->getNumContainedTypes(); i != e; ++i) { 14526974302e3ff20746268721959efed807c7711bfcBob Wilson AllocaInst *NA = new AllocaInst(ST->getContainedType(i), 0, 14534cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner AI->getAlignment(), 14544cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner AI->getName() + "." + Twine(i), AI); 14554cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner ElementAllocas.push_back(NA); 14564cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner WorkList.push_back(NA); // Add to worklist for recursive processing 14574cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 14584cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } else { 1459db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner ArrayType *AT = cast<ArrayType>(AI->getAllocatedType()); 14604cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner ElementAllocas.reserve(AT->getNumElements()); 1461db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *ElTy = AT->getElementType(); 14624cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner for (unsigned i = 0, e = AT->getNumElements(); i != e; ++i) { 14634cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner AllocaInst *NA = new AllocaInst(ElTy, 0, AI->getAlignment(), 14644cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner AI->getName() + "." + Twine(i), AI); 14654cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner ElementAllocas.push_back(NA); 14664cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner WorkList.push_back(NA); // Add to worklist for recursive processing 14674cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 14684cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 1469d2fa781169175b827e50953a1d0b7edc6b0c4801Chris Lattner 14704cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Now that we have created the new alloca instructions, rewrite all the 14714cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // uses of the old alloca. 14724cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner RewriteForScalarRepl(AI, AI, 0, ElementAllocas); 1473d2fa781169175b827e50953a1d0b7edc6b0c4801Chris Lattner 14744cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Now erase any instructions that were made dead while rewriting the alloca. 14754cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner DeleteDeadInstructions(); 14764cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner AI->eraseFromParent(); 14774cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 1478fe60104ac97f3a8736dcfbfdf9547c7b7cc7b951Dan Gohman ++NumReplaced; 14794cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner} 14804cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 14814cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// DeleteDeadInstructions - Erase instructions on the DeadInstrs list, 14824cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// recursively including all their operands that become trivially dead. 14834cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattnervoid SROA::DeleteDeadInstructions() { 14844cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner while (!DeadInsts.empty()) { 14854cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Instruction *I = cast<Instruction>(DeadInsts.pop_back_val()); 14864cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 14874cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner for (User::op_iterator OI = I->op_begin(), E = I->op_end(); OI != E; ++OI) 14884cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (Instruction *U = dyn_cast<Instruction>(*OI)) { 14894cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Zero out the operand and see if it becomes trivially dead. 14904cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // (But, don't add allocas to the dead instruction list -- they are 14914cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // already on the worklist and will be deleted separately.) 14924cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner *OI = 0; 14934cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (isInstructionTriviallyDead(U) && !isa<AllocaInst>(U)) 14944cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner DeadInsts.push_back(U); 1495d2fa781169175b827e50953a1d0b7edc6b0c4801Chris Lattner } 1496d2fa781169175b827e50953a1d0b7edc6b0c4801Chris Lattner 14974cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner I->eraseFromParent(); 14984cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 14994cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner} 15006974302e3ff20746268721959efed807c7711bfcBob Wilson 15014cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// isSafeForScalarRepl - Check if instruction I is a safe use with regard to 15024cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// performing scalar replacement of alloca AI. The results are flagged in 15034cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// the Info parameter. Offset indicates the position within AI that is 15044cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// referenced by this instruction. 15056c95d24927b11fb76bc3e76ebe6a8198d74fc178Chris Lattnervoid SROA::isSafeForScalarRepl(Instruction *I, uint64_t Offset, 15064cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner AllocaInfo &Info) { 15074cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner for (Value::use_iterator UI = I->use_begin(), E = I->use_end(); UI!=E; ++UI) { 15084cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Instruction *User = cast<Instruction>(*UI); 15094cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 15104cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (BitCastInst *BC = dyn_cast<BitCastInst>(User)) { 15116c95d24927b11fb76bc3e76ebe6a8198d74fc178Chris Lattner isSafeForScalarRepl(BC, Offset, Info); 15124cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } else if (GetElementPtrInst *GEPI = dyn_cast<GetElementPtrInst>(User)) { 15134cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t GEPOffset = Offset; 15146c95d24927b11fb76bc3e76ebe6a8198d74fc178Chris Lattner isSafeGEP(GEPI, GEPOffset, Info); 15154cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (!Info.isUnsafe) 15166c95d24927b11fb76bc3e76ebe6a8198d74fc178Chris Lattner isSafeForScalarRepl(GEPI, GEPOffset, Info); 151719101c7585c191376d898e3e66e35acd9bd777c2Gabor Greif } else if (MemIntrinsic *MI = dyn_cast<MemIntrinsic>(User)) { 15184cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner ConstantInt *Length = dyn_cast<ConstantInt>(MI->getLength()); 1519d01a0da090407762fe3b770d84f049d72d06467eChris Lattner if (Length == 0) 1520d01a0da090407762fe3b770d84f049d72d06467eChris Lattner return MarkUnsafe(Info, User); 15217e2fa3142aca46d9435a5804932ef76123c0cf71Aaron Ballman if (Length->isNegative()) 15227e2fa3142aca46d9435a5804932ef76123c0cf71Aaron Ballman return MarkUnsafe(Info, User); 15237e2fa3142aca46d9435a5804932ef76123c0cf71Aaron Ballman 15246c95d24927b11fb76bc3e76ebe6a8198d74fc178Chris Lattner isSafeMemAccess(Offset, Length->getZExtValue(), 0, 1525145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner UI.getOperandNo() == 0, Info, MI, 1526145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner true /*AllowWholeAccess*/); 15274cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } else if (LoadInst *LI = dyn_cast<LoadInst>(User)) { 15282bc3d52b9ab422ee9f7e42a1a4e3b818e623a5f7Eli Friedman if (!LI->isSimple()) 1529d01a0da090407762fe3b770d84f049d72d06467eChris Lattner return MarkUnsafe(Info, User); 1530db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *LIType = LI->getType(); 15316c95d24927b11fb76bc3e76ebe6a8198d74fc178Chris Lattner isSafeMemAccess(Offset, TD->getTypeAllocSize(LIType), 1532145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner LIType, false, Info, LI, true /*AllowWholeAccess*/); 1533d01a0da090407762fe3b770d84f049d72d06467eChris Lattner Info.hasALoadOrStore = true; 1534d01a0da090407762fe3b770d84f049d72d06467eChris Lattner 15354cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } else if (StoreInst *SI = dyn_cast<StoreInst>(User)) { 15364cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Store is ok if storing INTO the pointer, not storing the pointer 15372bc3d52b9ab422ee9f7e42a1a4e3b818e623a5f7Eli Friedman if (!SI->isSimple() || SI->getOperand(0) == I) 1538d01a0da090407762fe3b770d84f049d72d06467eChris Lattner return MarkUnsafe(Info, User); 1539d01a0da090407762fe3b770d84f049d72d06467eChris Lattner 1540db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *SIType = SI->getOperand(0)->getType(); 15416c95d24927b11fb76bc3e76ebe6a8198d74fc178Chris Lattner isSafeMemAccess(Offset, TD->getTypeAllocSize(SIType), 1542145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner SIType, true, Info, SI, true /*AllowWholeAccess*/); 1543145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner Info.hasALoadOrStore = true; 15445a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky } else if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(User)) { 15455a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky if (II->getIntrinsicID() != Intrinsic::lifetime_start && 15465a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky II->getIntrinsicID() != Intrinsic::lifetime_end) 15475a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky return MarkUnsafe(Info, User); 1548145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner } else if (isa<PHINode>(User) || isa<SelectInst>(User)) { 1549145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner isSafePHISelectUseForScalarRepl(User, Offset, Info); 1550145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner } else { 1551145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner return MarkUnsafe(Info, User); 1552145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner } 1553145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner if (Info.isUnsafe) return; 1554145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner } 1555145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner} 1556145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner 1557145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner 1558145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner/// isSafePHIUseForScalarRepl - If we see a PHI node or select using a pointer 1559145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner/// derived from the alloca, we can often still split the alloca into elements. 1560145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner/// This is useful if we have a large alloca where one element is phi'd 1561145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner/// together somewhere: we can SRoA and promote all the other elements even if 1562145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner/// we end up not being able to promote this one. 1563145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner/// 1564145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner/// All we require is that the uses of the PHI do not index into other parts of 1565145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner/// the alloca. The most important use case for this is single load and stores 1566145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner/// that are PHI'd together, which can happen due to code sinking. 1567145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattnervoid SROA::isSafePHISelectUseForScalarRepl(Instruction *I, uint64_t Offset, 1568145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner AllocaInfo &Info) { 1569145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner // If we've already checked this PHI, don't do it again. 1570145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner if (PHINode *PN = dyn_cast<PHINode>(I)) 1571145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner if (!Info.CheckedPHIs.insert(PN)) 1572145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner return; 1573145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner 1574145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner for (Value::use_iterator UI = I->use_begin(), E = I->use_end(); UI!=E; ++UI) { 1575145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner Instruction *User = cast<Instruction>(*UI); 1576145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner 1577145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner if (BitCastInst *BC = dyn_cast<BitCastInst>(User)) { 1578145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner isSafePHISelectUseForScalarRepl(BC, Offset, Info); 1579145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner } else if (GetElementPtrInst *GEPI = dyn_cast<GetElementPtrInst>(User)) { 1580145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner // Only allow "bitcast" GEPs for simplicity. We could generalize this, 1581145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner // but would have to prove that we're staying inside of an element being 1582145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner // promoted. 1583145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner if (!GEPI->hasAllZeroIndices()) 1584145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner return MarkUnsafe(Info, User); 1585145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner isSafePHISelectUseForScalarRepl(GEPI, Offset, Info); 1586145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner } else if (LoadInst *LI = dyn_cast<LoadInst>(User)) { 15872bc3d52b9ab422ee9f7e42a1a4e3b818e623a5f7Eli Friedman if (!LI->isSimple()) 1588145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner return MarkUnsafe(Info, User); 1589db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *LIType = LI->getType(); 1590145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner isSafeMemAccess(Offset, TD->getTypeAllocSize(LIType), 1591145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner LIType, false, Info, LI, false /*AllowWholeAccess*/); 1592145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner Info.hasALoadOrStore = true; 1593145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner 1594145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner } else if (StoreInst *SI = dyn_cast<StoreInst>(User)) { 1595145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner // Store is ok if storing INTO the pointer, not storing the pointer 15962bc3d52b9ab422ee9f7e42a1a4e3b818e623a5f7Eli Friedman if (!SI->isSimple() || SI->getOperand(0) == I) 1597145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner return MarkUnsafe(Info, User); 1598145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner 1599db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *SIType = SI->getOperand(0)->getType(); 1600145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner isSafeMemAccess(Offset, TD->getTypeAllocSize(SIType), 1601145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner SIType, true, Info, SI, false /*AllowWholeAccess*/); 1602d01a0da090407762fe3b770d84f049d72d06467eChris Lattner Info.hasALoadOrStore = true; 1603145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner } else if (isa<PHINode>(User) || isa<SelectInst>(User)) { 1604145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner isSafePHISelectUseForScalarRepl(User, Offset, Info); 16054cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } else { 1606d01a0da090407762fe3b770d84f049d72d06467eChris Lattner return MarkUnsafe(Info, User); 1607d2fa781169175b827e50953a1d0b7edc6b0c4801Chris Lattner } 16084cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (Info.isUnsafe) return; 1609d2fa781169175b827e50953a1d0b7edc6b0c4801Chris Lattner } 1610d2fa781169175b827e50953a1d0b7edc6b0c4801Chris Lattner} 1611d2fa781169175b827e50953a1d0b7edc6b0c4801Chris Lattner 16124cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// isSafeGEP - Check if a GEP instruction can be handled for scalar 16134cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// replacement. It is safe when all the indices are constant, in-bounds 16144cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// references, and when the resulting offset corresponds to an element within 16154cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// the alloca type. The results are flagged in the Info parameter. Upon 16164cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// return, Offset is adjusted as specified by the GEP indices. 16176c95d24927b11fb76bc3e76ebe6a8198d74fc178Chris Lattnervoid SROA::isSafeGEP(GetElementPtrInst *GEPI, 16184cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t &Offset, AllocaInfo &Info) { 16194cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner gep_type_iterator GEPIt = gep_type_begin(GEPI), E = gep_type_end(GEPI); 16204cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (GEPIt == E) 16214cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return; 16225ffe6acd577696a41932c7b82db06a04687e07baChris Lattner 16234cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Walk through the GEP type indices, checking the types that this indexes 16244cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // into. 16254cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner for (; GEPIt != E; ++GEPIt) { 16264cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Ignore struct elements, no extra checking needed for these. 16274cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if ((*GEPIt)->isStructTy()) 16284cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner continue; 16295ffe6acd577696a41932c7b82db06a04687e07baChris Lattner 16304cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner ConstantInt *IdxVal = dyn_cast<ConstantInt>(GEPIt.getOperand()); 16314cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (!IdxVal) 1632d01a0da090407762fe3b770d84f049d72d06467eChris Lattner return MarkUnsafe(Info, GEPI); 16335ffe6acd577696a41932c7b82db06a04687e07baChris Lattner } 163441b33f437f70dcf63e35d08e5f4202258ef05c15Eli Friedman 16354cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Compute the offset due to this GEP and check if the alloca has a 16364cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // component element at that offset. 16374cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner SmallVector<Value*, 8> Indices(GEPI->op_begin() + 1, GEPI->op_end()); 16388fbbb3980755d74539a0aed02bc18842ed2bd18dJay Foad Offset += TD->getIndexedOffset(GEPI->getPointerOperandType(), Indices); 16396c95d24927b11fb76bc3e76ebe6a8198d74fc178Chris Lattner if (!TypeHasComponent(Info.AI->getAllocatedType(), Offset, 0)) 1640d01a0da090407762fe3b770d84f049d72d06467eChris Lattner MarkUnsafe(Info, GEPI); 16414cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner} 164241b33f437f70dcf63e35d08e5f4202258ef05c15Eli Friedman 1643704d1347c5009f674408fae6f78343b415891274Bob Wilson/// isHomogeneousAggregate - Check if type T is a struct or array containing 1644704d1347c5009f674408fae6f78343b415891274Bob Wilson/// elements of the same type (which is always true for arrays). If so, 1645704d1347c5009f674408fae6f78343b415891274Bob Wilson/// return true with NumElts and EltTy set to the number of elements and the 1646704d1347c5009f674408fae6f78343b415891274Bob Wilson/// element type, respectively. 1647db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattnerstatic bool isHomogeneousAggregate(Type *T, unsigned &NumElts, 1648db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *&EltTy) { 1649db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner if (ArrayType *AT = dyn_cast<ArrayType>(T)) { 1650704d1347c5009f674408fae6f78343b415891274Bob Wilson NumElts = AT->getNumElements(); 1651f0908aeade2f41d2fed82de8d85448358b379328Bob Wilson EltTy = (NumElts == 0 ? 0 : AT->getElementType()); 1652704d1347c5009f674408fae6f78343b415891274Bob Wilson return true; 1653704d1347c5009f674408fae6f78343b415891274Bob Wilson } 1654db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner if (StructType *ST = dyn_cast<StructType>(T)) { 1655704d1347c5009f674408fae6f78343b415891274Bob Wilson NumElts = ST->getNumContainedTypes(); 1656f0908aeade2f41d2fed82de8d85448358b379328Bob Wilson EltTy = (NumElts == 0 ? 0 : ST->getContainedType(0)); 1657704d1347c5009f674408fae6f78343b415891274Bob Wilson for (unsigned n = 1; n < NumElts; ++n) { 1658704d1347c5009f674408fae6f78343b415891274Bob Wilson if (ST->getContainedType(n) != EltTy) 1659704d1347c5009f674408fae6f78343b415891274Bob Wilson return false; 1660704d1347c5009f674408fae6f78343b415891274Bob Wilson } 1661704d1347c5009f674408fae6f78343b415891274Bob Wilson return true; 1662704d1347c5009f674408fae6f78343b415891274Bob Wilson } 1663704d1347c5009f674408fae6f78343b415891274Bob Wilson return false; 1664704d1347c5009f674408fae6f78343b415891274Bob Wilson} 1665704d1347c5009f674408fae6f78343b415891274Bob Wilson 1666704d1347c5009f674408fae6f78343b415891274Bob Wilson/// isCompatibleAggregate - Check if T1 and T2 are either the same type or are 1667704d1347c5009f674408fae6f78343b415891274Bob Wilson/// "homogeneous" aggregates with the same element type and number of elements. 1668db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattnerstatic bool isCompatibleAggregate(Type *T1, Type *T2) { 1669704d1347c5009f674408fae6f78343b415891274Bob Wilson if (T1 == T2) 1670704d1347c5009f674408fae6f78343b415891274Bob Wilson return true; 1671704d1347c5009f674408fae6f78343b415891274Bob Wilson 1672704d1347c5009f674408fae6f78343b415891274Bob Wilson unsigned NumElts1, NumElts2; 1673db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *EltTy1, *EltTy2; 1674704d1347c5009f674408fae6f78343b415891274Bob Wilson if (isHomogeneousAggregate(T1, NumElts1, EltTy1) && 1675704d1347c5009f674408fae6f78343b415891274Bob Wilson isHomogeneousAggregate(T2, NumElts2, EltTy2) && 1676704d1347c5009f674408fae6f78343b415891274Bob Wilson NumElts1 == NumElts2 && 1677704d1347c5009f674408fae6f78343b415891274Bob Wilson EltTy1 == EltTy2) 1678704d1347c5009f674408fae6f78343b415891274Bob Wilson return true; 1679704d1347c5009f674408fae6f78343b415891274Bob Wilson 1680704d1347c5009f674408fae6f78343b415891274Bob Wilson return false; 1681704d1347c5009f674408fae6f78343b415891274Bob Wilson} 1682704d1347c5009f674408fae6f78343b415891274Bob Wilson 16834cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// isSafeMemAccess - Check if a load/store/memcpy operates on the entire AI 16844cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// alloca or has an offset and size that corresponds to a component element 16854cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// within it. The offset checked here may have been formed from a GEP with a 16864cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// pointer bitcasted to a different type. 1687145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner/// 1688145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner/// If AllowWholeAccess is true, then this allows uses of the entire alloca as a 1689145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner/// unit. If false, it only allows accesses known to be in a single element. 16906c95d24927b11fb76bc3e76ebe6a8198d74fc178Chris Lattnervoid SROA::isSafeMemAccess(uint64_t Offset, uint64_t MemSize, 1691db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *MemOpType, bool isStore, 1692145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner AllocaInfo &Info, Instruction *TheAccess, 1693145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner bool AllowWholeAccess) { 16944cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Check if this is a load/store of the entire alloca. 1695145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner if (Offset == 0 && AllowWholeAccess && 16966c95d24927b11fb76bc3e76ebe6a8198d74fc178Chris Lattner MemSize == TD->getTypeAllocSize(Info.AI->getAllocatedType())) { 1697704d1347c5009f674408fae6f78343b415891274Bob Wilson // This can be safe for MemIntrinsics (where MemOpType is 0) and integer 1698704d1347c5009f674408fae6f78343b415891274Bob Wilson // loads/stores (which are essentially the same as the MemIntrinsics with 1699704d1347c5009f674408fae6f78343b415891274Bob Wilson // regard to copying padding between elements). But, if an alloca is 1700704d1347c5009f674408fae6f78343b415891274Bob Wilson // flagged as both a source and destination of such operations, we'll need 1701704d1347c5009f674408fae6f78343b415891274Bob Wilson // to check later for padding between elements. 1702704d1347c5009f674408fae6f78343b415891274Bob Wilson if (!MemOpType || MemOpType->isIntegerTy()) { 1703704d1347c5009f674408fae6f78343b415891274Bob Wilson if (isStore) 1704704d1347c5009f674408fae6f78343b415891274Bob Wilson Info.isMemCpyDst = true; 1705704d1347c5009f674408fae6f78343b415891274Bob Wilson else 1706704d1347c5009f674408fae6f78343b415891274Bob Wilson Info.isMemCpySrc = true; 17074cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return; 17084cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 1709704d1347c5009f674408fae6f78343b415891274Bob Wilson // This is also safe for references using a type that is compatible with 1710704d1347c5009f674408fae6f78343b415891274Bob Wilson // the type of the alloca, so that loads/stores can be rewritten using 1711704d1347c5009f674408fae6f78343b415891274Bob Wilson // insertvalue/extractvalue. 17126c95d24927b11fb76bc3e76ebe6a8198d74fc178Chris Lattner if (isCompatibleAggregate(MemOpType, Info.AI->getAllocatedType())) { 17137e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner Info.hasSubelementAccess = true; 1714704d1347c5009f674408fae6f78343b415891274Bob Wilson return; 17157e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner } 17164cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 17174cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Check if the offset/size correspond to a component within the alloca type. 1718db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *T = Info.AI->getAllocatedType(); 17197e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner if (TypeHasComponent(T, Offset, MemSize)) { 17207e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner Info.hasSubelementAccess = true; 17214cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return; 17227e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner } 17234cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 1724d01a0da090407762fe3b770d84f049d72d06467eChris Lattner return MarkUnsafe(Info, TheAccess); 17255ffe6acd577696a41932c7b82db06a04687e07baChris Lattner} 17265ffe6acd577696a41932c7b82db06a04687e07baChris Lattner 17274cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// TypeHasComponent - Return true if T has a component type with the 17284cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// specified offset and size. If Size is zero, do not check the size. 1729db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattnerbool SROA::TypeHasComponent(Type *T, uint64_t Offset, uint64_t Size) { 1730db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *EltTy; 17314cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t EltSize; 1732db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner if (StructType *ST = dyn_cast<StructType>(T)) { 17334cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner const StructLayout *Layout = TD->getStructLayout(ST); 17344cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner unsigned EltIdx = Layout->getElementContainingOffset(Offset); 17354cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner EltTy = ST->getContainedType(EltIdx); 17364cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner EltSize = TD->getTypeAllocSize(EltTy); 17374cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Offset -= Layout->getElementOffset(EltIdx); 1738db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner } else if (ArrayType *AT = dyn_cast<ArrayType>(T)) { 17394cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner EltTy = AT->getElementType(); 17404cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner EltSize = TD->getTypeAllocSize(EltTy); 17414cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (Offset >= AT->getNumElements() * EltSize) 17424cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return false; 17434cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Offset %= EltSize; 17444cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } else { 17454cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return false; 17464cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 17474cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (Offset == 0 && (Size == 0 || EltSize == Size)) 17484cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return true; 17494cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Check if the component spans multiple elements. 17504cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (Offset + Size > EltSize) 17514cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return false; 17524cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return TypeHasComponent(EltTy, Offset, Size); 17534cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner} 17543cb3650a278e37aa6378127c51e407d2823139b4Duncan Sands 17554cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// RewriteForScalarRepl - Alloca AI is being split into NewElts, so rewrite 17564cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// the instruction I, which references it, to use the separate elements. 17574cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// Offset indicates the position within AI that is referenced by this 17584cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// instruction. 17594cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattnervoid SROA::RewriteForScalarRepl(Instruction *I, AllocaInst *AI, uint64_t Offset, 17604cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner SmallVector<AllocaInst*, 32> &NewElts) { 1761145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner for (Value::use_iterator UI = I->use_begin(), E = I->use_end(); UI!=E;) { 1762145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner Use &TheUse = UI.getUse(); 1763145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner Instruction *User = cast<Instruction>(*UI++); 17643cb3650a278e37aa6378127c51e407d2823139b4Duncan Sands 17654cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (BitCastInst *BC = dyn_cast<BitCastInst>(User)) { 17664cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner RewriteBitCast(BC, AI, Offset, NewElts); 1767145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner continue; 1768145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner } 1769145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner 1770145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner if (GetElementPtrInst *GEPI = dyn_cast<GetElementPtrInst>(User)) { 17714cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner RewriteGEP(GEPI, AI, Offset, NewElts); 1772145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner continue; 1773145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner } 1774145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner 1775145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner if (MemIntrinsic *MI = dyn_cast<MemIntrinsic>(User)) { 17764cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner ConstantInt *Length = dyn_cast<ConstantInt>(MI->getLength()); 17774cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t MemSize = Length->getZExtValue(); 17784cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (Offset == 0 && 17794cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner MemSize == TD->getTypeAllocSize(AI->getAllocatedType())) 17804cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner RewriteMemIntrinUserOfAlloca(MI, I, AI, NewElts); 17814cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Otherwise the intrinsic can only touch a single element and the 17824cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // address operand will be updated, so nothing else needs to be done. 1783145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner continue; 1784145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner } 17855a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky 17865a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(User)) { 17875a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky if (II->getIntrinsicID() == Intrinsic::lifetime_start || 17885a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky II->getIntrinsicID() == Intrinsic::lifetime_end) { 17895a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky RewriteLifetimeIntrinsic(II, AI, Offset, NewElts); 17905a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky } 17915a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky continue; 17925a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky } 1793145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner 1794145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner if (LoadInst *LI = dyn_cast<LoadInst>(User)) { 1795db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *LIType = LI->getType(); 1796192228edb1c08ca11da2df959072bcaa99eacd63Chris Lattner 1797704d1347c5009f674408fae6f78343b415891274Bob Wilson if (isCompatibleAggregate(LIType, AI->getAllocatedType())) { 17984cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Replace: 17994cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // %res = load { i32, i32 }* %alloc 18004cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // with: 18014cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // %load.0 = load i32* %alloc.0 18024cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // %insert.0 insertvalue { i32, i32 } zeroinitializer, i32 %load.0, 0 18034cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // %load.1 = load i32* %alloc.1 18044cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // %insert = insertvalue { i32, i32 } %insert.0, i32 %load.1, 1 18054cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // (Also works for arrays instead of structs) 18064cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *Insert = UndefValue::get(LIType); 1807abb25122050349ccf77f8afb198a985e7a4d95eeDevang Patel IRBuilder<> Builder(LI); 18084cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner for (unsigned i = 0, e = NewElts.size(); i != e; ++i) { 1809abb25122050349ccf77f8afb198a985e7a4d95eeDevang Patel Value *Load = Builder.CreateLoad(NewElts[i], "load"); 1810abb25122050349ccf77f8afb198a985e7a4d95eeDevang Patel Insert = Builder.CreateInsertValue(Insert, Load, i, "insert"); 18114cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 18124cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner LI->replaceAllUsesWith(Insert); 18134cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner DeadInsts.push_back(LI); 18144cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } else if (LIType->isIntegerTy() && 18154cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner TD->getTypeAllocSize(LIType) == 18164cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner TD->getTypeAllocSize(AI->getAllocatedType())) { 18174cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If this is a load of the entire alloca to an integer, rewrite it. 18184cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner RewriteLoadUserOfWholeAlloca(LI, AI, NewElts); 18194cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 1820145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner continue; 1821145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner } 1822145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner 1823145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner if (StoreInst *SI = dyn_cast<StoreInst>(User)) { 18244cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *Val = SI->getOperand(0); 1825db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *SIType = Val->getType(); 1826704d1347c5009f674408fae6f78343b415891274Bob Wilson if (isCompatibleAggregate(SIType, AI->getAllocatedType())) { 18274cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Replace: 18284cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // store { i32, i32 } %val, { i32, i32 }* %alloc 18294cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // with: 18304cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // %val.0 = extractvalue { i32, i32 } %val, 0 18314cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // store i32 %val.0, i32* %alloc.0 18324cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // %val.1 = extractvalue { i32, i32 } %val, 1 18334cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // store i32 %val.1, i32* %alloc.1 18344cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // (Also works for arrays instead of structs) 1835abb25122050349ccf77f8afb198a985e7a4d95eeDevang Patel IRBuilder<> Builder(SI); 18364cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner for (unsigned i = 0, e = NewElts.size(); i != e; ++i) { 1837abb25122050349ccf77f8afb198a985e7a4d95eeDevang Patel Value *Extract = Builder.CreateExtractValue(Val, i, Val->getName()); 1838abb25122050349ccf77f8afb198a985e7a4d95eeDevang Patel Builder.CreateStore(Extract, NewElts[i]); 18394cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 18404cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner DeadInsts.push_back(SI); 18414cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } else if (SIType->isIntegerTy() && 18424cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner TD->getTypeAllocSize(SIType) == 18434cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner TD->getTypeAllocSize(AI->getAllocatedType())) { 18444cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If this is a store of the entire alloca from an integer, rewrite it. 18454cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner RewriteStoreUserOfWholeAlloca(SI, AI, NewElts); 184639a1c04323a5993d6b2993e615ec44c16e19aeeaChris Lattner } 1847145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner continue; 1848145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner } 1849145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner 1850145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner if (isa<SelectInst>(User) || isa<PHINode>(User)) { 1851145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner // If we have a PHI user of the alloca itself (as opposed to a GEP or 1852145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner // bitcast) we have to rewrite it. GEP and bitcast uses will be RAUW'd to 1853145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner // the new pointer. 1854145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner if (!isa<AllocaInst>(I)) continue; 1855145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner 1856145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner assert(Offset == 0 && NewElts[0] && 1857145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner "Direct alloca use should have a zero offset"); 1858145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner 1859145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner // If we have a use of the alloca, we know the derived uses will be 1860145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner // utilizing just the first element of the scalarized result. Insert a 1861145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner // bitcast of the first alloca before the user as required. 1862145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner AllocaInst *NewAI = NewElts[0]; 1863145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner BitCastInst *BCI = new BitCastInst(NewAI, AI->getType(), "", NewAI); 1864145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner NewAI->moveBefore(BCI); 1865145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner TheUse = BCI; 1866145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner continue; 186739a1c04323a5993d6b2993e615ec44c16e19aeeaChris Lattner } 18684cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 18694cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner} 18703cb3650a278e37aa6378127c51e407d2823139b4Duncan Sands 18714cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// RewriteBitCast - Update a bitcast reference to the alloca being replaced 18724cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// and recursively continue updating all of its uses. 18734cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattnervoid SROA::RewriteBitCast(BitCastInst *BC, AllocaInst *AI, uint64_t Offset, 18744cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner SmallVector<AllocaInst*, 32> &NewElts) { 18754cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner RewriteForScalarRepl(BC, AI, Offset, NewElts); 18764cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (BC->getOperand(0) != AI) 18774cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return; 187839a1c04323a5993d6b2993e615ec44c16e19aeeaChris Lattner 18794cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // The bitcast references the original alloca. Replace its uses with 188075f69e3a3dff78cb89ded1d6c96ccb65603a82d9Eli Friedman // references to the alloca containing offset zero (which is normally at 188175f69e3a3dff78cb89ded1d6c96ccb65603a82d9Eli Friedman // index zero, but might not be in cases involving structs with elements 188275f69e3a3dff78cb89ded1d6c96ccb65603a82d9Eli Friedman // of size zero). 188375f69e3a3dff78cb89ded1d6c96ccb65603a82d9Eli Friedman Type *T = AI->getAllocatedType(); 188475f69e3a3dff78cb89ded1d6c96ccb65603a82d9Eli Friedman uint64_t EltOffset = 0; 188575f69e3a3dff78cb89ded1d6c96ccb65603a82d9Eli Friedman Type *IdxTy; 188675f69e3a3dff78cb89ded1d6c96ccb65603a82d9Eli Friedman uint64_t Idx = FindElementAndOffset(T, EltOffset, IdxTy); 188775f69e3a3dff78cb89ded1d6c96ccb65603a82d9Eli Friedman Instruction *Val = NewElts[Idx]; 18884cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (Val->getType() != BC->getDestTy()) { 18894cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Val = new BitCastInst(Val, BC->getDestTy(), "", BC); 18904cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Val->takeName(BC); 189139a1c04323a5993d6b2993e615ec44c16e19aeeaChris Lattner } 18924cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner BC->replaceAllUsesWith(Val); 18934cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner DeadInsts.push_back(BC); 189439a1c04323a5993d6b2993e615ec44c16e19aeeaChris Lattner} 1895372dda8881c7a32a6f5ce0f76a713e3a9ef46ea1Chris Lattner 18964cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// FindElementAndOffset - Return the index of the element containing Offset 18974cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// within the specified type, which must be either a struct or an array. 18984cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// Sets T to the type of the element and Offset to the offset within that 18994cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// element. IdxTy is set to the type of the index result to be used in a 19004cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// GEP instruction. 1901db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattneruint64_t SROA::FindElementAndOffset(Type *&T, uint64_t &Offset, 1902db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *&IdxTy) { 19034cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t Idx = 0; 1904db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner if (StructType *ST = dyn_cast<StructType>(T)) { 19054cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner const StructLayout *Layout = TD->getStructLayout(ST); 19064cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Idx = Layout->getElementContainingOffset(Offset); 19074cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner T = ST->getContainedType(Idx); 19084cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Offset -= Layout->getElementOffset(Idx); 19094cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner IdxTy = Type::getInt32Ty(T->getContext()); 19104cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return Idx; 1911f5990edc877c4e63503c589928a00ec6ec751830Chris Lattner } 1912db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner ArrayType *AT = cast<ArrayType>(T); 19134cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner T = AT->getElementType(); 19144cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t EltSize = TD->getTypeAllocSize(T); 19154cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Idx = Offset / EltSize; 19164cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Offset -= Idx * EltSize; 19174cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner IdxTy = Type::getInt64Ty(T->getContext()); 19184cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return Idx; 19195e062a1eda2c4adffd428a35e737a431fc37f4e0Chris Lattner} 1920a188894d67a3cc2516b25aae9b3cbdbff4b0babeChris Lattner 19214cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// RewriteGEP - Check if this GEP instruction moves the pointer across 19224cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// elements of the alloca that are being split apart, and if so, rewrite 19234cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// the GEP to be relative to the new element. 19244cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattnervoid SROA::RewriteGEP(GetElementPtrInst *GEPI, AllocaInst *AI, uint64_t Offset, 19254cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner SmallVector<AllocaInst*, 32> &NewElts) { 19264cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t OldOffset = Offset; 19274cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner SmallVector<Value*, 8> Indices(GEPI->op_begin() + 1, GEPI->op_end()); 19288fbbb3980755d74539a0aed02bc18842ed2bd18dJay Foad Offset += TD->getIndexedOffset(GEPI->getPointerOperandType(), Indices); 19294cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 19304cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner RewriteForScalarRepl(GEPI, AI, Offset, NewElts); 19314cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 1932db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *T = AI->getAllocatedType(); 1933db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *IdxTy; 19344cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t OldIdx = FindElementAndOffset(T, OldOffset, IdxTy); 19354cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (GEPI->getOperand(0) == AI) 19364cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner OldIdx = ~0ULL; // Force the GEP to be rewritten. 19374cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 19384cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner T = AI->getAllocatedType(); 19394cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t EltOffset = Offset; 19404cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t Idx = FindElementAndOffset(T, EltOffset, IdxTy); 19414cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 19424cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If this GEP does not move the pointer across elements of the alloca 19434cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // being split, then it does not needs to be rewritten. 19444cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (Idx == OldIdx) 1945c4472072641f702dbd99ae12b7da089e75c44a99Chris Lattner return; 1946c4472072641f702dbd99ae12b7da089e75c44a99Chris Lattner 1947db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *i32Ty = Type::getInt32Ty(AI->getContext()); 19484cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner SmallVector<Value*, 8> NewArgs; 19494cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner NewArgs.push_back(Constant::getNullValue(i32Ty)); 19504cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner while (EltOffset != 0) { 19514cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t EltIdx = FindElementAndOffset(T, EltOffset, IdxTy); 19524cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner NewArgs.push_back(ConstantInt::get(IdxTy, EltIdx)); 19532e0d5f84325303fa95997cd66485811bd0a6ef70Chris Lattner } 19544cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Instruction *Val = NewElts[Idx]; 19554cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (NewArgs.size() > 1) { 1956a9203109f4ac95aa7e9624f2838e3d89623ec902Jay Foad Val = GetElementPtrInst::CreateInBounds(Val, NewArgs, "", GEPI); 19574cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Val->takeName(GEPI); 19584cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 19594cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (Val->getType() != GEPI->getType()) 19604cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Val = new BitCastInst(Val, GEPI->getType(), Val->getName(), GEPI); 19614cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner GEPI->replaceAllUsesWith(Val); 19624cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner DeadInsts.push_back(GEPI); 1963a188894d67a3cc2516b25aae9b3cbdbff4b0babeChris Lattner} 1964a188894d67a3cc2516b25aae9b3cbdbff4b0babeChris Lattner 19655a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky/// RewriteLifetimeIntrinsic - II is a lifetime.start/lifetime.end. Rewrite it 19665a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky/// to mark the lifetime of the scalarized memory. 19675a1cb644c903da49dc612a0ba5044505d066259eNick Lewyckyvoid SROA::RewriteLifetimeIntrinsic(IntrinsicInst *II, AllocaInst *AI, 19685a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky uint64_t Offset, 19695a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky SmallVector<AllocaInst*, 32> &NewElts) { 19705a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky ConstantInt *OldSize = cast<ConstantInt>(II->getArgOperand(0)); 19715a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky // Put matching lifetime markers on everything from Offset up to 19725a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky // Offset+OldSize. 19735a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky Type *AIType = AI->getAllocatedType(); 19745a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky uint64_t NewOffset = Offset; 19755a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky Type *IdxTy; 19765a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky uint64_t Idx = FindElementAndOffset(AIType, NewOffset, IdxTy); 19775a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky 19785a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky IRBuilder<> Builder(II); 19795a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky uint64_t Size = OldSize->getLimitedValue(); 19805a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky 19815a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky if (NewOffset) { 19825a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky // Splice the first element and index 'NewOffset' bytes in. SROA will 19835a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky // split the alloca again later. 19845a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky Value *V = Builder.CreateBitCast(NewElts[Idx], Builder.getInt8PtrTy()); 19855a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky V = Builder.CreateGEP(V, Builder.getInt64(NewOffset)); 19865a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky 19875a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky IdxTy = NewElts[Idx]->getAllocatedType(); 19885a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky uint64_t EltSize = TD->getTypeAllocSize(IdxTy) - NewOffset; 19895a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky if (EltSize > Size) { 19905a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky EltSize = Size; 19915a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky Size = 0; 19925a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky } else { 19935a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky Size -= EltSize; 19945a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky } 19955a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky if (II->getIntrinsicID() == Intrinsic::lifetime_start) 19965a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky Builder.CreateLifetimeStart(V, Builder.getInt64(EltSize)); 19975a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky else 19985a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky Builder.CreateLifetimeEnd(V, Builder.getInt64(EltSize)); 19995a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky ++Idx; 20005a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky } 20015a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky 20025a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky for (; Idx != NewElts.size() && Size; ++Idx) { 20035a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky IdxTy = NewElts[Idx]->getAllocatedType(); 20045a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky uint64_t EltSize = TD->getTypeAllocSize(IdxTy); 20055a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky if (EltSize > Size) { 20065a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky EltSize = Size; 20075a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky Size = 0; 20085a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky } else { 20095a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky Size -= EltSize; 20105a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky } 20115a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky if (II->getIntrinsicID() == Intrinsic::lifetime_start) 20125a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky Builder.CreateLifetimeStart(NewElts[Idx], 20135a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky Builder.getInt64(EltSize)); 20145a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky else 20155a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky Builder.CreateLifetimeEnd(NewElts[Idx], 20165a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky Builder.getInt64(EltSize)); 20175a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky } 20185a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky DeadInsts.push_back(II); 20195a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky} 20205a1cb644c903da49dc612a0ba5044505d066259eNick Lewycky 20214cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// RewriteMemIntrinUserOfAlloca - MI is a memcpy/memset/memmove from or to AI. 20224cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// Rewrite it to copy or set the elements of the scalarized memory. 20234cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattnervoid SROA::RewriteMemIntrinUserOfAlloca(MemIntrinsic *MI, Instruction *Inst, 20244cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner AllocaInst *AI, 20254cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner SmallVector<AllocaInst*, 32> &NewElts) { 20264cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If this is a memcpy/memmove, construct the other pointer as the 20274cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // appropriate type. The "Other" pointer is the pointer that goes to memory 20284cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // that doesn't have anything to do with the alloca that we are promoting. For 20294cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // memset, this Value* stays null. 20304cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *OtherPtr = 0; 20314cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner unsigned MemAlignment = MI->getAlignment(); 20324cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (MemTransferInst *MTI = dyn_cast<MemTransferInst>(MI)) { // memmove/memcopy 20334cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (Inst == MTI->getRawDest()) 20344cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner OtherPtr = MTI->getRawSource(); 20354cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner else { 20364cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner assert(Inst == MTI->getRawSource()); 20374cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner OtherPtr = MTI->getRawDest(); 2038a188894d67a3cc2516b25aae9b3cbdbff4b0babeChris Lattner } 20394cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 20403ce5e887aef457701da95f1c6ccbd58ec3d32fe4Chris Lattner 20414cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If there is an other pointer, we want to convert it to the same pointer 20424cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // type as AI has, so we can GEP through it safely. 20434cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (OtherPtr) { 20440238f8c430050d23ef861169bb4c4f930af0ef97Chris Lattner unsigned AddrSpace = 20450238f8c430050d23ef861169bb4c4f930af0ef97Chris Lattner cast<PointerType>(OtherPtr->getType())->getAddressSpace(); 20464cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 20474cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Remove bitcasts and all-zero GEPs from OtherPtr. This is an 20484cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // optimization, but it's also required to detect the corner case where 20494cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // both pointer operands are referencing the same memory, and where 20504cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // OtherPtr may be a bitcast or GEP that currently being rewritten. (This 20514cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // function is only called for mem intrinsics that access the whole 20524cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // aggregate, so non-zero GEPs are not an issue here.) 20530238f8c430050d23ef861169bb4c4f930af0ef97Chris Lattner OtherPtr = OtherPtr->stripPointerCasts(); 20546974302e3ff20746268721959efed807c7711bfcBob Wilson 20554cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Copying the alloca to itself is a no-op: just delete it. 20564cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (OtherPtr == AI || OtherPtr == NewElts[0]) { 20574cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // This code will run twice for a no-op memcpy -- once for each operand. 20584cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Put only one reference to MI on the DeadInsts list. 20594cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner for (SmallVector<Value*, 32>::const_iterator I = DeadInsts.begin(), 20604cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner E = DeadInsts.end(); I != E; ++I) 20614cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (*I == MI) return; 20624cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner DeadInsts.push_back(MI); 20634cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return; 2064c570487d45f7426dc5f75c0309122d6f9330ecf7Chris Lattner } 20656974302e3ff20746268721959efed807c7711bfcBob Wilson 20664cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If the pointer is not the right type, insert a bitcast to the right 20674cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // type. 2068db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *NewTy = 20690238f8c430050d23ef861169bb4c4f930af0ef97Chris Lattner PointerType::get(AI->getType()->getElementType(), AddrSpace); 20706974302e3ff20746268721959efed807c7711bfcBob Wilson 20710238f8c430050d23ef861169bb4c4f930af0ef97Chris Lattner if (OtherPtr->getType() != NewTy) 20720238f8c430050d23ef861169bb4c4f930af0ef97Chris Lattner OtherPtr = new BitCastInst(OtherPtr, NewTy, OtherPtr->getName(), MI); 2073a188894d67a3cc2516b25aae9b3cbdbff4b0babeChris Lattner } 20746974302e3ff20746268721959efed807c7711bfcBob Wilson 20754cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Process each element of the aggregate. 20764cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner bool SROADest = MI->getRawDest() == Inst; 20776974302e3ff20746268721959efed807c7711bfcBob Wilson 20784cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Constant *Zero = Constant::getNullValue(Type::getInt32Ty(MI->getContext())); 20794b3dfbd220835cbba519162712c9cb6afaa44059Duncan Sands 20804cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner for (unsigned i = 0, e = NewElts.size(); i != e; ++i) { 20814cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If this is a memcpy/memmove, emit a GEP of the other element address. 20824cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *OtherElt = 0; 20834cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner unsigned OtherEltAlign = MemAlignment; 20846974302e3ff20746268721959efed807c7711bfcBob Wilson 20854cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (OtherPtr) { 20864cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *Idx[2] = { Zero, 20874cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner ConstantInt::get(Type::getInt32Ty(MI->getContext()), i) }; 2088a9203109f4ac95aa7e9624f2838e3d89623ec902Jay Foad OtherElt = GetElementPtrInst::CreateInBounds(OtherPtr, Idx, 20894cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner OtherPtr->getName()+"."+Twine(i), 20904cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner MI); 20914cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t EltOffset; 2092db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner PointerType *OtherPtrTy = cast<PointerType>(OtherPtr->getType()); 2093db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *OtherTy = OtherPtrTy->getElementType(); 2094db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner if (StructType *ST = dyn_cast<StructType>(OtherTy)) { 20954cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner EltOffset = TD->getStructLayout(ST)->getElementOffset(i); 20964cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } else { 2097db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *EltTy = cast<SequentialType>(OtherTy)->getElementType(); 20984cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner EltOffset = TD->getTypeAllocSize(EltTy)*i; 20994cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 21006974302e3ff20746268721959efed807c7711bfcBob Wilson 21014cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // The alignment of the other pointer is the guaranteed alignment of the 21024cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // element, which is affected by both the known alignment of the whole 21034cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // mem intrinsic and the alignment of the element. If the alignment of 21044cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // the memcpy (f.e.) is 32 but the element is at a 4-byte offset, then the 21054cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // known alignment is just 4 bytes. 21064cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner OtherEltAlign = (unsigned)MinAlign(OtherEltAlign, EltOffset); 21079bc67da0a9982f2f7597d1d46cf18f079e4f8f98Chris Lattner } 21086974302e3ff20746268721959efed807c7711bfcBob Wilson 21094cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *EltPtr = NewElts[i]; 2110db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *EltTy = cast<PointerType>(EltPtr->getType())->getElementType(); 21116974302e3ff20746268721959efed807c7711bfcBob Wilson 21124cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If we got down to a scalar, insert a load or store as appropriate. 21134cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (EltTy->isSingleValueType()) { 21144cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (isa<MemTransferInst>(MI)) { 21154cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (SROADest) { 21164cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // From Other to Alloca. 21174cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *Elt = new LoadInst(OtherElt, "tmp", false, OtherEltAlign, MI); 21184cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner new StoreInst(Elt, EltPtr, MI); 21194cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } else { 21204cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // From Alloca to Other. 21214cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *Elt = new LoadInst(EltPtr, "tmp", MI); 21224cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner new StoreInst(Elt, OtherElt, false, OtherEltAlign, MI); 21234cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 21244cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner continue; 212533e24adc3bc3d046aa05cf903fb74da1610b57cbChris Lattner } 21264cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner assert(isa<MemSetInst>(MI)); 21276974302e3ff20746268721959efed807c7711bfcBob Wilson 21284cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If the stored element is zero (common case), just store a null 21294cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // constant. 21304cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Constant *StoreVal; 21316f14c8c7c1ec97797a04631abad6885bfaabcc6dGabor Greif if (ConstantInt *CI = dyn_cast<ConstantInt>(MI->getArgOperand(1))) { 21324cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (CI->isZero()) { 21334cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner StoreVal = Constant::getNullValue(EltTy); // 0.0, null, 0, <0,0> 21344cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } else { 21354cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If EltTy is a vector type, get the element type. 2136db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *ValTy = EltTy->getScalarType(); 2137c570487d45f7426dc5f75c0309122d6f9330ecf7Chris Lattner 21384cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Construct an integer with the right value. 21394cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner unsigned EltSize = TD->getTypeSizeInBits(ValTy); 21404cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner APInt OneVal(EltSize, CI->getZExtValue()); 21414cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner APInt TotalVal(OneVal); 21424cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Set each byte. 21434cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner for (unsigned i = 0; 8*i < EltSize; ++i) { 21444cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner TotalVal = TotalVal.shl(8); 21454cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner TotalVal |= OneVal; 21464cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 21476974302e3ff20746268721959efed807c7711bfcBob Wilson 21484cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Convert the integer value to the appropriate type. 2149d55c1c16598eba6111fb3a5b6e5dbc6469a562f7Chris Lattner StoreVal = ConstantInt::get(CI->getContext(), TotalVal); 21504cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (ValTy->isPointerTy()) 21514cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner StoreVal = ConstantExpr::getIntToPtr(StoreVal, ValTy); 21524cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner else if (ValTy->isFloatingPointTy()) 21534cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner StoreVal = ConstantExpr::getBitCast(StoreVal, ValTy); 21544cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner assert(StoreVal->getType() == ValTy && "Type mismatch!"); 21556974302e3ff20746268721959efed807c7711bfcBob Wilson 21564cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If the requested value was a vector constant, create it. 2157c055a8782ee66f6041cc00997857d98d6b9e9b4aCameron Zwarich if (EltTy->isVectorTy()) { 2158c055a8782ee66f6041cc00997857d98d6b9e9b4aCameron Zwarich unsigned NumElts = cast<VectorType>(EltTy)->getNumElements(); 21594ca829e89567f002fc74eb0e3e532a7c7662e031Chris Lattner StoreVal = ConstantVector::getSplat(NumElts, StoreVal); 21604cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 21614cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 21624cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner new StoreInst(StoreVal, EltPtr, MI); 21634cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner continue; 21644cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 21654cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Otherwise, if we're storing a byte variable, use a memset call for 21664cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // this element. 21674cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 21686974302e3ff20746268721959efed807c7711bfcBob Wilson 21694cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner unsigned EltSize = TD->getTypeAllocSize(EltTy); 217075f69e3a3dff78cb89ded1d6c96ccb65603a82d9Eli Friedman if (!EltSize) 217175f69e3a3dff78cb89ded1d6c96ccb65603a82d9Eli Friedman continue; 21726974302e3ff20746268721959efed807c7711bfcBob Wilson 217361db1f56d0b717d67557bbb2a9d83af1449458cbChris Lattner IRBuilder<> Builder(MI); 21746974302e3ff20746268721959efed807c7711bfcBob Wilson 21754cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Finally, insert the meminst for this element. 217661db1f56d0b717d67557bbb2a9d83af1449458cbChris Lattner if (isa<MemSetInst>(MI)) { 217761db1f56d0b717d67557bbb2a9d83af1449458cbChris Lattner Builder.CreateMemSet(EltPtr, MI->getArgOperand(1), EltSize, 217861db1f56d0b717d67557bbb2a9d83af1449458cbChris Lattner MI->isVolatile()); 21794cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } else { 218061db1f56d0b717d67557bbb2a9d83af1449458cbChris Lattner assert(isa<MemTransferInst>(MI)); 218161db1f56d0b717d67557bbb2a9d83af1449458cbChris Lattner Value *Dst = SROADest ? EltPtr : OtherElt; // Dest ptr 218261db1f56d0b717d67557bbb2a9d83af1449458cbChris Lattner Value *Src = SROADest ? OtherElt : EltPtr; // Src ptr 21836974302e3ff20746268721959efed807c7711bfcBob Wilson 218461db1f56d0b717d67557bbb2a9d83af1449458cbChris Lattner if (isa<MemCpyInst>(MI)) 218561db1f56d0b717d67557bbb2a9d83af1449458cbChris Lattner Builder.CreateMemCpy(Dst, Src, EltSize, OtherEltAlign,MI->isVolatile()); 218661db1f56d0b717d67557bbb2a9d83af1449458cbChris Lattner else 218761db1f56d0b717d67557bbb2a9d83af1449458cbChris Lattner Builder.CreateMemMove(Dst, Src, EltSize,OtherEltAlign,MI->isVolatile()); 21884cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 2189a188894d67a3cc2516b25aae9b3cbdbff4b0babeChris Lattner } 21904cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner DeadInsts.push_back(MI); 2191a188894d67a3cc2516b25aae9b3cbdbff4b0babeChris Lattner} 219279b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner 21934cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// RewriteStoreUserOfWholeAlloca - We found a store of an integer that 21944cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// overwrites the entire allocation. Extract out the pieces of the stored 21954cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// integer and store them individually. 21964cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattnervoid SROA::RewriteStoreUserOfWholeAlloca(StoreInst *SI, AllocaInst *AI, 21974cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner SmallVector<AllocaInst*, 32> &NewElts){ 21984cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Extract each element out of the integer according to its structure offset 21994cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // and store the element value to the individual alloca. 22004cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *SrcVal = SI->getOperand(0); 2201db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *AllocaEltTy = AI->getAllocatedType(); 22024cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t AllocaSizeBits = TD->getTypeAllocSizeInBits(AllocaEltTy); 22036974302e3ff20746268721959efed807c7711bfcBob Wilson 220470728532799d751b8e0e97719dcb3344a2fc97deChris Lattner IRBuilder<> Builder(SI); 220570728532799d751b8e0e97719dcb3344a2fc97deChris Lattner 22064cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Handle tail padding by extending the operand 22074cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (TD->getTypeSizeInBits(SrcVal->getType()) != AllocaSizeBits) 220870728532799d751b8e0e97719dcb3344a2fc97deChris Lattner SrcVal = Builder.CreateZExt(SrcVal, 220970728532799d751b8e0e97719dcb3344a2fc97deChris Lattner IntegerType::get(SI->getContext(), AllocaSizeBits)); 22104b3dfbd220835cbba519162712c9cb6afaa44059Duncan Sands 22114cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner DEBUG(dbgs() << "PROMOTING STORE TO WHOLE ALLOCA: " << *AI << '\n' << *SI 22124cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner << '\n'); 22134b3dfbd220835cbba519162712c9cb6afaa44059Duncan Sands 22144cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // There are two forms here: AI could be an array or struct. Both cases 22154cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // have different ways to compute the element offset. 2216db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner if (StructType *EltSTy = dyn_cast<StructType>(AllocaEltTy)) { 22174cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner const StructLayout *Layout = TD->getStructLayout(EltSTy); 22186974302e3ff20746268721959efed807c7711bfcBob Wilson 22194cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner for (unsigned i = 0, e = NewElts.size(); i != e; ++i) { 22204cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Get the number of bits to shift SrcVal to get the value. 2221db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *FieldTy = EltSTy->getElementType(i); 22224cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t Shift = Layout->getElementOffsetInBits(i); 22236974302e3ff20746268721959efed807c7711bfcBob Wilson 22244cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (TD->isBigEndian()) 22254cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Shift = AllocaSizeBits-Shift-TD->getTypeAllocSizeInBits(FieldTy); 22266974302e3ff20746268721959efed807c7711bfcBob Wilson 22274cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *EltVal = SrcVal; 22284cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (Shift) { 22294cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *ShiftVal = ConstantInt::get(EltVal->getType(), Shift); 223070728532799d751b8e0e97719dcb3344a2fc97deChris Lattner EltVal = Builder.CreateLShr(EltVal, ShiftVal, "sroa.store.elt"); 22314cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 22326974302e3ff20746268721959efed807c7711bfcBob Wilson 22334cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Truncate down to an integer of the right size. 22344cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t FieldSizeBits = TD->getTypeSizeInBits(FieldTy); 22356974302e3ff20746268721959efed807c7711bfcBob Wilson 22364cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Ignore zero sized fields like {}, they obviously contain no data. 22374cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (FieldSizeBits == 0) continue; 22386974302e3ff20746268721959efed807c7711bfcBob Wilson 22394cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (FieldSizeBits != AllocaSizeBits) 224070728532799d751b8e0e97719dcb3344a2fc97deChris Lattner EltVal = Builder.CreateTrunc(EltVal, 224170728532799d751b8e0e97719dcb3344a2fc97deChris Lattner IntegerType::get(SI->getContext(), FieldSizeBits)); 22424cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *DestField = NewElts[i]; 22434cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (EltVal->getType() == FieldTy) { 22444cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Storing to an integer field of this size, just do it. 22454cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } else if (FieldTy->isFloatingPointTy() || FieldTy->isVectorTy()) { 22464cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Bitcast to the right element type (for fp/vector values). 224770728532799d751b8e0e97719dcb3344a2fc97deChris Lattner EltVal = Builder.CreateBitCast(EltVal, FieldTy); 22484cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } else { 22494cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Otherwise, bitcast the dest pointer (for aggregates). 225070728532799d751b8e0e97719dcb3344a2fc97deChris Lattner DestField = Builder.CreateBitCast(DestField, 225170728532799d751b8e0e97719dcb3344a2fc97deChris Lattner PointerType::getUnqual(EltVal->getType())); 22524cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 22534cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner new StoreInst(EltVal, DestField, SI); 22544cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 22556974302e3ff20746268721959efed807c7711bfcBob Wilson 22569d34c4d678cfc836a59a114b7b2cf91e9dd5eac4Chris Lattner } else { 2257db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner ArrayType *ATy = cast<ArrayType>(AllocaEltTy); 2258db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *ArrayEltTy = ATy->getElementType(); 22594cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t ElementOffset = TD->getTypeAllocSizeInBits(ArrayEltTy); 22604cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t ElementSizeBits = TD->getTypeSizeInBits(ArrayEltTy); 22614b3dfbd220835cbba519162712c9cb6afaa44059Duncan Sands 22624cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t Shift; 22636974302e3ff20746268721959efed807c7711bfcBob Wilson 22644cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (TD->isBigEndian()) 22654cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Shift = AllocaSizeBits-ElementOffset; 22666974302e3ff20746268721959efed807c7711bfcBob Wilson else 22674cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Shift = 0; 22686974302e3ff20746268721959efed807c7711bfcBob Wilson 22694cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner for (unsigned i = 0, e = NewElts.size(); i != e; ++i) { 22704cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Ignore zero sized fields like {}, they obviously contain no data. 22714cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (ElementSizeBits == 0) continue; 22726974302e3ff20746268721959efed807c7711bfcBob Wilson 22734cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *EltVal = SrcVal; 22744cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (Shift) { 22754cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *ShiftVal = ConstantInt::get(EltVal->getType(), Shift); 227670728532799d751b8e0e97719dcb3344a2fc97deChris Lattner EltVal = Builder.CreateLShr(EltVal, ShiftVal, "sroa.store.elt"); 22774cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 22786974302e3ff20746268721959efed807c7711bfcBob Wilson 22794cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Truncate down to an integer of the right size. 22804cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (ElementSizeBits != AllocaSizeBits) 228170728532799d751b8e0e97719dcb3344a2fc97deChris Lattner EltVal = Builder.CreateTrunc(EltVal, 228270728532799d751b8e0e97719dcb3344a2fc97deChris Lattner IntegerType::get(SI->getContext(), 228370728532799d751b8e0e97719dcb3344a2fc97deChris Lattner ElementSizeBits)); 22844cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *DestField = NewElts[i]; 22854cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (EltVal->getType() == ArrayEltTy) { 22864cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Storing to an integer field of this size, just do it. 22874cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } else if (ArrayEltTy->isFloatingPointTy() || 22884cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner ArrayEltTy->isVectorTy()) { 22894cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Bitcast to the right element type (for fp/vector values). 229070728532799d751b8e0e97719dcb3344a2fc97deChris Lattner EltVal = Builder.CreateBitCast(EltVal, ArrayEltTy); 22914cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } else { 22924cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Otherwise, bitcast the dest pointer (for aggregates). 229370728532799d751b8e0e97719dcb3344a2fc97deChris Lattner DestField = Builder.CreateBitCast(DestField, 229470728532799d751b8e0e97719dcb3344a2fc97deChris Lattner PointerType::getUnqual(EltVal->getType())); 22954cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 22964cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner new StoreInst(EltVal, DestField, SI); 22976974302e3ff20746268721959efed807c7711bfcBob Wilson 22984cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (TD->isBigEndian()) 22994cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Shift -= ElementOffset; 23006974302e3ff20746268721959efed807c7711bfcBob Wilson else 23014cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Shift += ElementOffset; 23024cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 2303800de31776356910eb877e71df9f32b0a6215324Chris Lattner } 23046974302e3ff20746268721959efed807c7711bfcBob Wilson 23054cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner DeadInsts.push_back(SI); 2306800de31776356910eb877e71df9f32b0a6215324Chris Lattner} 2307800de31776356910eb877e71df9f32b0a6215324Chris Lattner 23084cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// RewriteLoadUserOfWholeAlloca - We found a load of the entire allocation to 23094cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// an integer. Load the individual pieces to form the aggregate value. 23104cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattnervoid SROA::RewriteLoadUserOfWholeAlloca(LoadInst *LI, AllocaInst *AI, 23114cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner SmallVector<AllocaInst*, 32> &NewElts) { 23124cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Extract each element out of the NewElts according to its structure offset 23134cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // and form the result value. 2314db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *AllocaEltTy = AI->getAllocatedType(); 23154cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t AllocaSizeBits = TD->getTypeAllocSizeInBits(AllocaEltTy); 23166974302e3ff20746268721959efed807c7711bfcBob Wilson 23174cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner DEBUG(dbgs() << "PROMOTING LOAD OF WHOLE ALLOCA: " << *AI << '\n' << *LI 23184cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner << '\n'); 23196974302e3ff20746268721959efed807c7711bfcBob Wilson 23204cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // There are two forms here: AI could be an array or struct. Both cases 23214cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // have different ways to compute the element offset. 23224cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner const StructLayout *Layout = 0; 23234cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t ArrayEltBitOffset = 0; 2324db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner if (StructType *EltSTy = dyn_cast<StructType>(AllocaEltTy)) { 23254cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Layout = TD->getStructLayout(EltSTy); 23264cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } else { 2327db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *ArrayEltTy = cast<ArrayType>(AllocaEltTy)->getElementType(); 23284cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner ArrayEltBitOffset = TD->getTypeAllocSizeInBits(ArrayEltTy); 23296974302e3ff20746268721959efed807c7711bfcBob Wilson } 23306974302e3ff20746268721959efed807c7711bfcBob Wilson 23316974302e3ff20746268721959efed807c7711bfcBob Wilson Value *ResultVal = 23324cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Constant::getNullValue(IntegerType::get(LI->getContext(), AllocaSizeBits)); 23336974302e3ff20746268721959efed807c7711bfcBob Wilson 23344cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner for (unsigned i = 0, e = NewElts.size(); i != e; ++i) { 23354cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Load the value from the alloca. If the NewElt is an aggregate, cast 23364cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // the pointer to an integer of the same size before doing the load. 23374cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *SrcField = NewElts[i]; 2338db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner Type *FieldTy = 23394cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner cast<PointerType>(SrcField->getType())->getElementType(); 23404cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t FieldSizeBits = TD->getTypeSizeInBits(FieldTy); 23416974302e3ff20746268721959efed807c7711bfcBob Wilson 23424cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Ignore zero sized fields like {}, they obviously contain no data. 23434cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (FieldSizeBits == 0) continue; 23446974302e3ff20746268721959efed807c7711bfcBob Wilson 2345db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner IntegerType *FieldIntTy = IntegerType::get(LI->getContext(), 23464cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner FieldSizeBits); 23474cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (!FieldTy->isIntegerTy() && !FieldTy->isFloatingPointTy() && 23484cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner !FieldTy->isVectorTy()) 23494cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner SrcField = new BitCastInst(SrcField, 23504cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner PointerType::getUnqual(FieldIntTy), 23514cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner "", LI); 23524cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner SrcField = new LoadInst(SrcField, "sroa.load.elt", LI); 235329e641761e81bd000bdc4ccfae479c6dda18e402Chris Lattner 23544cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // If SrcField is a fp or vector of the right size but that isn't an 23554cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // integer type, bitcast to an integer so we can shift it. 23564cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (SrcField->getType() != FieldIntTy) 23574cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner SrcField = new BitCastInst(SrcField, FieldIntTy, "", LI); 235829e641761e81bd000bdc4ccfae479c6dda18e402Chris Lattner 23594cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Zero extend the field to be the same size as the final alloca so that 23604cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // we can shift and insert it. 23614cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (SrcField->getType() != ResultVal->getType()) 23624cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner SrcField = new ZExtInst(SrcField, ResultVal->getType(), "", LI); 23636974302e3ff20746268721959efed807c7711bfcBob Wilson 23644cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Determine the number of bits to shift SrcField. 23654cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner uint64_t Shift; 23664cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (Layout) // Struct case. 23674cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Shift = Layout->getElementOffsetInBits(i); 23684cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner else // Array case. 23694cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Shift = i*ArrayEltBitOffset; 23706974302e3ff20746268721959efed807c7711bfcBob Wilson 23714cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (TD->isBigEndian()) 23724cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Shift = AllocaSizeBits-Shift-FieldIntTy->getBitWidth(); 23736974302e3ff20746268721959efed807c7711bfcBob Wilson 23744cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (Shift) { 23754cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner Value *ShiftVal = ConstantInt::get(SrcField->getType(), Shift); 23764cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner SrcField = BinaryOperator::CreateShl(SrcField, ShiftVal, "", LI); 23779b872db775797dea4b391a9347cfbd2ca9c558e2Chris Lattner } 23784cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 23791495247f517c0ac3aeeb9e6c7c0205dd7849d332Chris Lattner // Don't create an 'or x, 0' on the first iteration. 23801495247f517c0ac3aeeb9e6c7c0205dd7849d332Chris Lattner if (!isa<Constant>(ResultVal) || 23811495247f517c0ac3aeeb9e6c7c0205dd7849d332Chris Lattner !cast<Constant>(ResultVal)->isNullValue()) 23821495247f517c0ac3aeeb9e6c7c0205dd7849d332Chris Lattner ResultVal = BinaryOperator::CreateOr(SrcField, ResultVal, "", LI); 23831495247f517c0ac3aeeb9e6c7c0205dd7849d332Chris Lattner else 23841495247f517c0ac3aeeb9e6c7c0205dd7849d332Chris Lattner ResultVal = SrcField; 23859b872db775797dea4b391a9347cfbd2ca9c558e2Chris Lattner } 23864b3dfbd220835cbba519162712c9cb6afaa44059Duncan Sands 23874cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Handle tail padding by truncating the result 23884cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (TD->getTypeSizeInBits(LI->getType()) != AllocaSizeBits) 23894cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner ResultVal = new TruncInst(ResultVal, LI->getType(), "", LI); 23904b3dfbd220835cbba519162712c9cb6afaa44059Duncan Sands 23914cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner LI->replaceAllUsesWith(ResultVal); 23924cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner DeadInsts.push_back(LI); 23934cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner} 23944cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 23954cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// HasPadding - Return true if the specified type has any structure or 2396694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson/// alignment padding in between the elements that would be split apart 2397694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson/// by SROA; return false otherwise. 2398db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattnerstatic bool HasPadding(Type *Ty, const TargetData &TD) { 2399db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner if (ArrayType *ATy = dyn_cast<ArrayType>(Ty)) { 2400694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson Ty = ATy->getElementType(); 2401694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson return TD.getTypeSizeInBits(Ty) != TD.getTypeAllocSizeInBits(Ty); 2402694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson } 24034cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 2404694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson // SROA currently handles only Arrays and Structs. 2405db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner StructType *STy = cast<StructType>(Ty); 2406694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson const StructLayout *SL = TD.getStructLayout(STy); 2407694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson unsigned PrevFieldBitOffset = 0; 2408694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson for (unsigned i = 0, e = STy->getNumElements(); i != e; ++i) { 2409694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson unsigned FieldBitOffset = SL->getElementOffsetInBits(i); 2410694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson 2411694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson // Check to see if there is any padding between this element and the 2412694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson // previous one. 2413694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson if (i) { 2414694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson unsigned PrevFieldEnd = 24154cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner PrevFieldBitOffset+TD.getTypeSizeInBits(STy->getElementType(i-1)); 2416694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson if (PrevFieldEnd < FieldBitOffset) 24174cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return true; 24184cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner } 2419694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson PrevFieldBitOffset = FieldBitOffset; 24202e0d5f84325303fa95997cd66485811bd0a6ef70Chris Lattner } 2421694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson // Check for tail padding. 2422694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson if (unsigned EltCount = STy->getNumElements()) { 2423694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson unsigned PrevFieldEnd = PrevFieldBitOffset + 2424694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson TD.getTypeSizeInBits(STy->getElementType(EltCount-1)); 2425694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson if (PrevFieldEnd < SL->getSizeInBits()) 2426694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson return true; 2427694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson } 2428694a10e7d8410f24639971224ce0e282c8cd04cbBob Wilson return false; 24294cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner} 24304b3dfbd220835cbba519162712c9cb6afaa44059Duncan Sands 24314cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// isSafeStructAllocaToScalarRepl - Check to see if the specified allocation of 24324cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// an aggregate can be broken down into elements. Return 0 if not, 3 if safe, 24334cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner/// or 1 if safe after canonicalization has been performed. 24344cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattnerbool SROA::isSafeAllocaToScalarRepl(AllocaInst *AI) { 24354cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Loop over the use list of the alloca. We can only transform it if all of 24364cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // the users are safe to transform. 24376c95d24927b11fb76bc3e76ebe6a8198d74fc178Chris Lattner AllocaInfo Info(AI); 24386974302e3ff20746268721959efed807c7711bfcBob Wilson 24396c95d24927b11fb76bc3e76ebe6a8198d74fc178Chris Lattner isSafeForScalarRepl(AI, 0, Info); 24404cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (Info.isUnsafe) { 24414cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner DEBUG(dbgs() << "Cannot transform: " << *AI << '\n'); 24424cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return false; 2443800de31776356910eb877e71df9f32b0a6215324Chris Lattner } 24446974302e3ff20746268721959efed807c7711bfcBob Wilson 24454cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // Okay, we know all the users are promotable. If the aggregate is a memcpy 24464cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // source and destination, we have to be careful. In particular, the memcpy 24474cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // could be moving around elements that live in structure padding of the LLVM 24484cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // types, but may actually be used. In these cases, we refuse to promote the 24494cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner // struct. 24504cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner if (Info.isMemCpySrc && Info.isMemCpyDst && 24514cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner HasPadding(AI->getAllocatedType(), *TD)) 24524cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return false; 24534cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner 2454396a0567cf959d86a8a1ad185e54d84f5dacbacfChris Lattner // If the alloca never has an access to just *part* of it, but is accessed 2455396a0567cf959d86a8a1ad185e54d84f5dacbacfChris Lattner // via loads and stores, then we should use ConvertToScalarInfo to promote 24567e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner // the alloca instead of promoting each piece at a time and inserting fission 24577e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner // and fusion code. 24587e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner if (!Info.hasSubelementAccess && Info.hasALoadOrStore) { 24597e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner // If the struct/array just has one element, use basic SRoA. 2460db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner if (StructType *ST = dyn_cast<StructType>(AI->getAllocatedType())) { 24617e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner if (ST->getNumElements() > 1) return false; 24627e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner } else { 24637e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner if (cast<ArrayType>(AI->getAllocatedType())->getNumElements() > 1) 24647e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner return false; 24657e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner } 24667e9b427c879ae32b72fd24aeaf011e87e5692fd7Chris Lattner } 2467145c532e68acdf70d40bab5bc2034f692848b8dcChris Lattner 24684cc576bc5ea27951f3bb15ccefbe483293bf8eafChris Lattner return true; 2469800de31776356910eb877e71df9f32b0a6215324Chris Lattner} 2470800de31776356910eb877e71df9f32b0a6215324Chris Lattner 2471800de31776356910eb877e71df9f32b0a6215324Chris Lattner 247279b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner 247379b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner/// PointsToConstantGlobal - Return true if V (possibly indirectly) points to 247479b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner/// some part of a constant global variable. This intentionally only accepts 247579b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner/// constant expressions because we don't can't rewrite arbitrary instructions. 247679b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattnerstatic bool PointsToConstantGlobal(Value *V) { 247779b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner if (GlobalVariable *GV = dyn_cast<GlobalVariable>(V)) 247879b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner return GV->isConstant(); 247979b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner if (ConstantExpr *CE = dyn_cast<ConstantExpr>(V)) 24806974302e3ff20746268721959efed807c7711bfcBob Wilson if (CE->getOpcode() == Instruction::BitCast || 248179b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner CE->getOpcode() == Instruction::GetElementPtr) 248279b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner return PointsToConstantGlobal(CE->getOperand(0)); 248379b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner return false; 248479b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner} 248579b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner 248679b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner/// isOnlyCopiedFromConstantGlobal - Recursively walk the uses of a (derived) 248779b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner/// pointer to an alloca. Ignore any reads of the pointer, return false if we 248879b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner/// see any stores or other unknown uses. If we see pointer arithmetic, keep 248979b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner/// track of whether it moves the pointer (with isOffset) but otherwise traverse 249079b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner/// the uses. If we see a memcpy/memmove that targets an unoffseted pointer to 2491081f80078dccf02c1f9c61378ff88bbf1b4afb5eNick Lewycky/// the alloca, and if the source pointer is a pointer to a constant global, we 249279b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner/// can optimize this. 24939174d5c7383490d79b6a483d73cded54e32275d6Nick Lewyckystatic bool 24949174d5c7383490d79b6a483d73cded54e32275d6Nick LewyckyisOnlyCopiedFromConstantGlobal(Value *V, MemTransferInst *&TheCopy, 24959174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky bool isOffset, 24969174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky SmallVector<Instruction *, 4> &LifetimeMarkers) { 24979174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky // We track lifetime intrinsics as we encounter them. If we decide to go 24989174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky // ahead and replace the value with the global, this lets the caller quickly 24999174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky // eliminate the markers. 25009174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky 250179b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner for (Value::use_iterator UI = V->use_begin(), E = V->use_end(); UI!=E; ++UI) { 25028a8a4350db3e66a517dc179ba38439c66bb726a8Gabor Greif User *U = cast<Instruction>(*UI); 25038a8a4350db3e66a517dc179ba38439c66bb726a8Gabor Greif 25042e61849f45144f2f05d57b00947df7e101610694Chris Lattner if (LoadInst *LI = dyn_cast<LoadInst>(U)) { 25056e733d34ca487ab7ff8a6def018a933620393869Chris Lattner // Ignore non-volatile loads, they are always ok. 25062bc3d52b9ab422ee9f7e42a1a4e3b818e623a5f7Eli Friedman if (!LI->isSimple()) return false; 25072e61849f45144f2f05d57b00947df7e101610694Chris Lattner continue; 25082e61849f45144f2f05d57b00947df7e101610694Chris Lattner } 25096974302e3ff20746268721959efed807c7711bfcBob Wilson 25108a8a4350db3e66a517dc179ba38439c66bb726a8Gabor Greif if (BitCastInst *BCI = dyn_cast<BitCastInst>(U)) { 251179b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner // If uses of the bitcast are ok, we are ok. 25129174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky if (!isOnlyCopiedFromConstantGlobal(BCI, TheCopy, isOffset, 25139174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky LifetimeMarkers)) 251479b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner return false; 251579b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner continue; 251679b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner } 25178a8a4350db3e66a517dc179ba38439c66bb726a8Gabor Greif if (GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(U)) { 251879b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner // If the GEP has all zero indices, it doesn't offset the pointer. If it 251979b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner // doesn't, it does. 252079b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner if (!isOnlyCopiedFromConstantGlobal(GEP, TheCopy, 25219174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky isOffset || !GEP->hasAllZeroIndices(), 25229174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky LifetimeMarkers)) 252379b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner return false; 252479b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner continue; 252579b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner } 25266974302e3ff20746268721959efed807c7711bfcBob Wilson 25276248065194778c866164b0c10f09f0f0d91b91acChris Lattner if (CallSite CS = U) { 2528081f80078dccf02c1f9c61378ff88bbf1b4afb5eNick Lewycky // If this is the function being called then we treat it like a load and 2529081f80078dccf02c1f9c61378ff88bbf1b4afb5eNick Lewycky // ignore it. 2530081f80078dccf02c1f9c61378ff88bbf1b4afb5eNick Lewycky if (CS.isCallee(UI)) 2531081f80078dccf02c1f9c61378ff88bbf1b4afb5eNick Lewycky continue; 25326974302e3ff20746268721959efed807c7711bfcBob Wilson 25335389210e638401b8982b6de7c4e4a16999007035Duncan Sands // If this is a readonly/readnone call site, then we know it is just a 25345389210e638401b8982b6de7c4e4a16999007035Duncan Sands // load (but one that potentially returns the value itself), so we can 25355389210e638401b8982b6de7c4e4a16999007035Duncan Sands // ignore it if we know that the value isn't captured. 25365389210e638401b8982b6de7c4e4a16999007035Duncan Sands unsigned ArgNo = CS.getArgumentNo(UI); 25375389210e638401b8982b6de7c4e4a16999007035Duncan Sands if (CS.onlyReadsMemory() && 2538173862e5468fbcf4b022b9088d2c81b25c2d60c5Nick Lewycky (CS.getInstruction()->use_empty() || CS.doesNotCapture(ArgNo))) 25395389210e638401b8982b6de7c4e4a16999007035Duncan Sands continue; 25405389210e638401b8982b6de7c4e4a16999007035Duncan Sands 25416248065194778c866164b0c10f09f0f0d91b91acChris Lattner // If this is being passed as a byval argument, the caller is making a 25426248065194778c866164b0c10f09f0f0d91b91acChris Lattner // copy, so it is only a read of the alloca. 2543173862e5468fbcf4b022b9088d2c81b25c2d60c5Nick Lewycky if (CS.isByValArgument(ArgNo)) 25446248065194778c866164b0c10f09f0f0d91b91acChris Lattner continue; 25456248065194778c866164b0c10f09f0f0d91b91acChris Lattner } 25466974302e3ff20746268721959efed807c7711bfcBob Wilson 25479174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky // Lifetime intrinsics can be handled by the caller. 25489174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(U)) { 25499174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky if (II->getIntrinsicID() == Intrinsic::lifetime_start || 25509174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky II->getIntrinsicID() == Intrinsic::lifetime_end) { 25519174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky assert(II->use_empty() && "Lifetime markers have no result to use!"); 25529174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky LifetimeMarkers.push_back(II); 25539174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky continue; 25549174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky } 25559174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky } 25569174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky 255779b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner // If this is isn't our memcpy/memmove, reject it as something we can't 255879b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner // handle. 255931d80103d56c026403d7fb6c50833664ff63ddcbChris Lattner MemTransferInst *MI = dyn_cast<MemTransferInst>(U); 256031d80103d56c026403d7fb6c50833664ff63ddcbChris Lattner if (MI == 0) 256179b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner return false; 25626974302e3ff20746268721959efed807c7711bfcBob Wilson 25632e61849f45144f2f05d57b00947df7e101610694Chris Lattner // If the transfer is using the alloca as a source of the transfer, then 25642e29ebd9e8efefe3ff926aa99cf2e5323665998eChris Lattner // ignore it since it is a load (unless the transfer is volatile). 25652e61849f45144f2f05d57b00947df7e101610694Chris Lattner if (UI.getOperandNo() == 1) { 25662e61849f45144f2f05d57b00947df7e101610694Chris Lattner if (MI->isVolatile()) return false; 25672e61849f45144f2f05d57b00947df7e101610694Chris Lattner continue; 25682e61849f45144f2f05d57b00947df7e101610694Chris Lattner } 256979b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner 257079b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner // If we already have seen a copy, reject the second one. 257179b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner if (TheCopy) return false; 25726974302e3ff20746268721959efed807c7711bfcBob Wilson 257379b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner // If the pointer has been offset from the start of the alloca, we can't 257479b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner // safely handle this. 257579b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner if (isOffset) return false; 257679b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner 257779b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner // If the memintrinsic isn't using the alloca as the dest, reject it. 2578a6aac4c5bc22bb10c7adb11eee3f82c703af7002Gabor Greif if (UI.getOperandNo() != 0) return false; 25796974302e3ff20746268721959efed807c7711bfcBob Wilson 258079b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner // If the source of the memcpy/move is not a constant global, reject it. 258131d80103d56c026403d7fb6c50833664ff63ddcbChris Lattner if (!PointsToConstantGlobal(MI->getSource())) 258279b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner return false; 25836974302e3ff20746268721959efed807c7711bfcBob Wilson 258479b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner // Otherwise, the transform is safe. Remember the copy instruction. 258579b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner TheCopy = MI; 258679b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner } 258779b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner return true; 258879b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner} 258979b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner 259079b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner/// isOnlyCopiedFromConstantGlobal - Return true if the specified alloca is only 259179b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner/// modified by a copy from a constant global. If we can prove this, we can 259279b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner/// replace any uses of the alloca with uses of the global directly. 25939174d5c7383490d79b6a483d73cded54e32275d6Nick LewyckyMemTransferInst * 25949174d5c7383490d79b6a483d73cded54e32275d6Nick LewyckySROA::isOnlyCopiedFromConstantGlobal(AllocaInst *AI, 25959174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky SmallVector<Instruction*, 4> &ToDelete) { 259631d80103d56c026403d7fb6c50833664ff63ddcbChris Lattner MemTransferInst *TheCopy = 0; 25979174d5c7383490d79b6a483d73cded54e32275d6Nick Lewycky if (::isOnlyCopiedFromConstantGlobal(AI, TheCopy, false, ToDelete)) 259879b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner return TheCopy; 259979b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner return 0; 260079b3bd395dc3303cde65e18e0524ed2f70268c99Chris Lattner} 2601