From 36b56886974eae4f9c5ebc96befd3e7bfe5de338 Mon Sep 17 00:00:00 2001 From: Stephen Hines Date: Wed, 23 Apr 2014 16:57:46 -0700 Subject: Update to LLVM 3.5a. Change-Id: Ifadecab779f128e62e430c2b4f6ddd84953ed617 --- lib/Transforms/Scalar/DeadStoreElimination.cpp | 99 ++++++++++---------------- 1 file changed, 39 insertions(+), 60 deletions(-) (limited to 'lib/Transforms/Scalar/DeadStoreElimination.cpp') diff --git a/lib/Transforms/Scalar/DeadStoreElimination.cpp b/lib/Transforms/Scalar/DeadStoreElimination.cpp index 57432c7..f54c00d 100644 --- a/lib/Transforms/Scalar/DeadStoreElimination.cpp +++ b/lib/Transforms/Scalar/DeadStoreElimination.cpp @@ -22,12 +22,12 @@ #include "llvm/ADT/Statistic.h" #include "llvm/Analysis/AliasAnalysis.h" #include "llvm/Analysis/CaptureTracking.h" -#include "llvm/Analysis/Dominators.h" #include "llvm/Analysis/MemoryBuiltins.h" #include "llvm/Analysis/MemoryDependenceAnalysis.h" #include "llvm/Analysis/ValueTracking.h" #include "llvm/IR/Constants.h" #include "llvm/IR/DataLayout.h" +#include "llvm/IR/Dominators.h" #include "llvm/IR/Function.h" #include "llvm/IR/GlobalVariable.h" #include "llvm/IR/Instructions.h" @@ -53,10 +53,13 @@ namespace { initializeDSEPass(*PassRegistry::getPassRegistry()); } - virtual bool runOnFunction(Function &F) { + bool runOnFunction(Function &F) override { + if (skipOptnoneFunction(F)) + return false; + AA = &getAnalysis(); MD = &getAnalysis(); - DT = &getAnalysis(); + DT = &getAnalysis().getDomTree(); TLI = AA->getTargetLibraryInfo(); bool Changed = false; @@ -76,13 +79,13 @@ namespace { void RemoveAccessedObjects(const AliasAnalysis::Location &LoadedLoc, SmallSetVector &DeadStackObjects); - virtual void getAnalysisUsage(AnalysisUsage &AU) const { + void getAnalysisUsage(AnalysisUsage &AU) const override { AU.setPreservesCFG(); - AU.addRequired(); + AU.addRequired(); AU.addRequired(); AU.addRequired(); AU.addPreserved(); - AU.addPreserved(); + AU.addPreserved(); AU.addPreserved(); } }; @@ -90,7 +93,7 @@ namespace { char DSE::ID = 0; INITIALIZE_PASS_BEGIN(DSE, "dse", "Dead Store Elimination", false, false) -INITIALIZE_PASS_DEPENDENCY(DominatorTree) +INITIALIZE_PASS_DEPENDENCY(DominatorTreeWrapperPass) INITIALIZE_PASS_DEPENDENCY(MemoryDependenceAnalysis) INITIALIZE_AG_DEPENDENCY(AliasAnalysis) INITIALIZE_PASS_END(DSE, "dse", "Dead Store Elimination", false, false) @@ -190,6 +193,7 @@ static bool hasMemoryWrite(Instruction *I, const TargetLibraryInfo *TLI) { /// describe the memory operations for this instruction. static AliasAnalysis::Location getLocForWrite(Instruction *Inst, AliasAnalysis &AA) { + const DataLayout *DL = AA.getDataLayout(); if (StoreInst *SI = dyn_cast(Inst)) return AA.getLocation(SI); @@ -199,7 +203,7 @@ getLocForWrite(Instruction *Inst, AliasAnalysis &AA) { // If we don't have target data around, an unknown size in Location means // that we should use the size of the pointee type. This isn't valid for // memset/memcpy, which writes more than an i8. - if (Loc.Size == AliasAnalysis::UnknownSize && AA.getDataLayout() == 0) + if (Loc.Size == AliasAnalysis::UnknownSize && DL == 0) return AliasAnalysis::Location(); return Loc; } @@ -213,7 +217,7 @@ getLocForWrite(Instruction *Inst, AliasAnalysis &AA) { // If we don't have target data around, an unknown size in Location means // that we should use the size of the pointee type. This isn't valid for // init.trampoline, which writes more than an i8. - if (AA.getDataLayout() == 0) return AliasAnalysis::Location(); + if (DL == 0) return AliasAnalysis::Location(); // FIXME: We don't know the size of the trampoline, so we can't really // handle it here. @@ -341,6 +345,7 @@ static OverwriteResult isOverwrite(const AliasAnalysis::Location &Later, AliasAnalysis &AA, int64_t &EarlierOff, int64_t &LaterOff) { + const DataLayout *DL = AA.getDataLayout(); const Value *P1 = Earlier.Ptr->stripPointerCasts(); const Value *P2 = Later.Ptr->stripPointerCasts(); @@ -354,8 +359,7 @@ static OverwriteResult isOverwrite(const AliasAnalysis::Location &Later, // If we have no DataLayout information around, then the size of the store // is inferrable from the pointee type. If they are the same type, then // we know that the store is safe. - if (AA.getDataLayout() == 0 && - Later.Ptr->getType() == Earlier.Ptr->getType()) + if (DL == 0 && Later.Ptr->getType() == Earlier.Ptr->getType()) return OverwriteComplete; return OverwriteUnknown; @@ -369,17 +373,14 @@ static OverwriteResult isOverwrite(const AliasAnalysis::Location &Later, // Otherwise, we have to have size information, and the later store has to be // larger than the earlier one. if (Later.Size == AliasAnalysis::UnknownSize || - Earlier.Size == AliasAnalysis::UnknownSize || - AA.getDataLayout() == 0) + Earlier.Size == AliasAnalysis::UnknownSize || DL == 0) return OverwriteUnknown; // Check to see if the later store is to the entire object (either a global, - // an alloca, or a byval argument). If so, then it clearly overwrites any - // other store to the same object. - const DataLayout *TD = AA.getDataLayout(); - - const Value *UO1 = GetUnderlyingObject(P1, TD), - *UO2 = GetUnderlyingObject(P2, TD); + // an alloca, or a byval/inalloca argument). If so, then it clearly + // overwrites any other store to the same object. + const Value *UO1 = GetUnderlyingObject(P1, DL), + *UO2 = GetUnderlyingObject(P2, DL); // If we can't resolve the same pointers to the same object, then we can't // analyze them at all. @@ -397,8 +398,8 @@ static OverwriteResult isOverwrite(const AliasAnalysis::Location &Later, // pointers are equal, then we can reason about the two stores. EarlierOff = 0; LaterOff = 0; - const Value *BP1 = GetPointerBaseWithConstantOffset(P1, EarlierOff, TD); - const Value *BP2 = GetPointerBaseWithConstantOffset(P2, LaterOff, TD); + const Value *BP1 = GetPointerBaseWithConstantOffset(P1, EarlierOff, DL); + const Value *BP2 = GetPointerBaseWithConstantOffset(P2, LaterOff, DL); // If the base pointers still differ, we have two completely different stores. if (BP1 != BP2) @@ -679,7 +680,7 @@ bool DSE::HandleFree(CallInst *F) { if (!AA->isMustAlias(F->getArgOperand(0), DepPointer)) break; - Instruction *Next = llvm::next(BasicBlock::iterator(Dependency)); + Instruction *Next = std::next(BasicBlock::iterator(Dependency)); // DCE instructions only used to calculate that store DeleteDeadInstruction(Dependency, *MD, TLI); @@ -701,22 +702,6 @@ bool DSE::HandleFree(CallInst *F) { return MadeChange; } -namespace { - struct CouldRef { - typedef Value *argument_type; - const CallSite CS; - AliasAnalysis *AA; - - bool operator()(Value *I) { - // See if the call site touches the value. - AliasAnalysis::ModRefResult A = - AA->getModRefInfo(CS, I, getPointerSize(I, *AA)); - - return A == AliasAnalysis::ModRef || A == AliasAnalysis::Ref; - } - }; -} - /// handleEndBlock - Remove dead stores to stack-allocated locations in the /// function end block. Ex: /// %A = alloca i32 @@ -742,11 +727,11 @@ bool DSE::handleEndBlock(BasicBlock &BB) { DeadStackObjects.insert(I); } - // Treat byval arguments the same, stores to them are dead at the end of the - // function. + // Treat byval or inalloca arguments the same, stores to them are dead at the + // end of the function. for (Function::arg_iterator AI = BB.getParent()->arg_begin(), AE = BB.getParent()->arg_end(); AI != AE; ++AI) - if (AI->hasByValAttr()) + if (AI->hasByValOrInAllocaAttr()) DeadStackObjects.insert(AI); // Scan the basic block backwards @@ -776,7 +761,7 @@ bool DSE::handleEndBlock(BasicBlock &BB) { for (SmallVectorImpl::iterator I = Pointers.begin(), E = Pointers.end(); I != E; ++I) { dbgs() << **I; - if (llvm::next(I) != E) + if (std::next(I) != E) dbgs() << ", "; } dbgs() << '\n'); @@ -818,8 +803,13 @@ bool DSE::handleEndBlock(BasicBlock &BB) { // If the call might load from any of our allocas, then any store above // the call is live. - CouldRef Pred = { CS, AA }; - DeadStackObjects.remove_if(Pred); + DeadStackObjects.remove_if([&](Value *I) { + // See if the call site touches the value. + AliasAnalysis::ModRefResult A = + AA->getModRefInfo(CS, I, getPointerSize(I, *AA)); + + return A == AliasAnalysis::ModRef || A == AliasAnalysis::Ref; + }); // If all of the allocas were clobbered by the call then we're not going // to find anything else to process. @@ -862,20 +852,6 @@ bool DSE::handleEndBlock(BasicBlock &BB) { return MadeChange; } -namespace { - struct CouldAlias { - typedef Value *argument_type; - const AliasAnalysis::Location &LoadedLoc; - AliasAnalysis *AA; - - bool operator()(Value *I) { - // See if the loaded location could alias the stack location. - AliasAnalysis::Location StackLoc(I, getPointerSize(I, *AA)); - return !AA->isNoAlias(StackLoc, LoadedLoc); - } - }; -} - /// RemoveAccessedObjects - Check to see if the specified location may alias any /// of the stack objects in the DeadStackObjects set. If so, they become live /// because the location is being loaded. @@ -895,6 +871,9 @@ void DSE::RemoveAccessedObjects(const AliasAnalysis::Location &LoadedLoc, } // Remove objects that could alias LoadedLoc. - CouldAlias Pred = { LoadedLoc, AA }; - DeadStackObjects.remove_if(Pred); + DeadStackObjects.remove_if([&](Value *I) { + // See if the loaded location could alias the stack location. + AliasAnalysis::Location StackLoc(I, getPointerSize(I, *AA)); + return !AA->isNoAlias(StackLoc, LoadedLoc); + }); } -- cgit v1.1