diff --git a/llvm/lib/Transforms/Scalar/LoopIdiomRecognize.cpp b/llvm/lib/Transforms/Scalar/LoopIdiomRecognize.cpp --- a/llvm/lib/Transforms/Scalar/LoopIdiomRecognize.cpp +++ b/llvm/lib/Transforms/Scalar/LoopIdiomRecognize.cpp @@ -1010,6 +1010,29 @@ return true; } +class ExpandedValuesCleaner { + SCEVExpander &Expander; + TargetLibraryInfo *TLI; + SmallVector ExpandedValues; + bool Commit = false; + +public: + ExpandedValuesCleaner(SCEVExpander &Expander, TargetLibraryInfo *TLI) + : Expander(Expander), TLI(TLI) {} + + void add(Value *V) { ExpandedValues.push_back(V); } + + void commit() { Commit = true; } + + ~ExpandedValuesCleaner() { + if (!Commit) { + Expander.clear(); + for (auto *V : ExpandedValues) + RecursivelyDeleteTriviallyDeadInstructions(V, TLI); + } + } +}; + /// If the stored value is a strided load in the same loop with the same stride /// this may be transformable into a memcpy. This kicks in for stuff like /// for (i) A[i] = B[i]; @@ -1040,6 +1063,8 @@ IRBuilder<> Builder(Preheader->getTerminator()); SCEVExpander Expander(*SE, *DL, "loop-idiom"); + ExpandedValuesCleaner EVC(Expander, TLI); + const SCEV *StrStart = StoreEv->getStart(); unsigned StrAS = SI->getPointerAddressSpace(); Type *IntIdxTy = Builder.getIntNTy(DL->getIndexSizeInBits(StrAS)); @@ -1056,16 +1081,13 @@ // checking everything. Value *StoreBasePtr = Expander.expandCodeFor( StrStart, Builder.getInt8PtrTy(StrAS), Preheader->getTerminator()); + EVC.add(StoreBasePtr); SmallPtrSet Stores; Stores.insert(SI); if (mayLoopAccessLocation(StoreBasePtr, ModRefInfo::ModRef, CurLoop, BECount, - StoreSize, *AA, Stores)) { - Expander.clear(); - // If we generated new code for the base pointer, clean up. - RecursivelyDeleteTriviallyDeadInstructions(StoreBasePtr, TLI); + StoreSize, *AA, Stores)) return false; - } const SCEV *LdStart = LoadEv->getStart(); unsigned LdAS = LI->getPointerAddressSpace(); @@ -1078,15 +1100,11 @@ // mutated by the loop. Value *LoadBasePtr = Expander.expandCodeFor( LdStart, Builder.getInt8PtrTy(LdAS), Preheader->getTerminator()); + EVC.add(LoadBasePtr); if (mayLoopAccessLocation(LoadBasePtr, ModRefInfo::Mod, CurLoop, BECount, - StoreSize, *AA, Stores)) { - Expander.clear(); - // If we generated new code for the base pointer, clean up. - RecursivelyDeleteTriviallyDeadInstructions(LoadBasePtr, TLI); - RecursivelyDeleteTriviallyDeadInstructions(StoreBasePtr, TLI); + StoreSize, *AA, Stores)) return false; - } if (avoidLIRForMultiBlockLoop()) return false; @@ -1098,6 +1116,7 @@ Value *NumBytes = Expander.expandCodeFor(NumBytesS, IntIdxTy, Preheader->getTerminator()); + EVC.add(NumBytes); CallInst *NewCall = nullptr; // Check whether to generate an unordered atomic memcpy: @@ -1157,6 +1176,7 @@ if (MSSAU && VerifyMemorySSA) MSSAU->getMemorySSA()->verifyMemorySSA(); ++NumMemCpy; + EVC.commit(); return true; }