diff options
Diffstat (limited to 'lib/Transforms/Utils/SimplifyLibCalls.cpp')
-rw-r--r-- | lib/Transforms/Utils/SimplifyLibCalls.cpp | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/lib/Transforms/Utils/SimplifyLibCalls.cpp b/lib/Transforms/Utils/SimplifyLibCalls.cpp index b4dc93dead..c3ea63852f 100644 --- a/lib/Transforms/Utils/SimplifyLibCalls.cpp +++ b/lib/Transforms/Utils/SimplifyLibCalls.cpp @@ -997,6 +997,25 @@ struct MemMoveOpt : public LibCallOptimization { } }; +struct MemSetOpt : public LibCallOptimization { + virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) { + // These optimizations require DataLayout. + if (!TD) return 0; + + FunctionType *FT = Callee->getFunctionType(); + if (FT->getNumParams() != 3 || FT->getReturnType() != FT->getParamType(0) || + !FT->getParamType(0)->isPointerTy() || + !FT->getParamType(1)->isIntegerTy() || + FT->getParamType(2) != TD->getIntPtrType(*Context)) + return 0; + + // memset(p, v, n) -> llvm.memset(p, v, n, 1) + Value *Val = B.CreateIntCast(CI->getArgOperand(1), B.getInt8Ty(), false); + B.CreateMemSet(CI->getArgOperand(0), Val, CI->getArgOperand(2), 1); + return CI->getArgOperand(0); + } +}; + } // End anonymous namespace. namespace llvm { @@ -1036,6 +1055,7 @@ class LibCallSimplifierImpl { MemCmpOpt MemCmp; MemCpyOpt MemCpy; MemMoveOpt MemMove; + MemSetOpt MemSet; void initOptimizations(); void addOpt(LibFunc::Func F, LibCallOptimization* Opt); @@ -1087,6 +1107,7 @@ void LibCallSimplifierImpl::initOptimizations() { addOpt(LibFunc::memcmp, &MemCmp); addOpt(LibFunc::memcpy, &MemCpy); addOpt(LibFunc::memmove, &MemMove); + addOpt(LibFunc::memset, &MemSet); } Value *LibCallSimplifierImpl::optimizeCall(CallInst *CI) { |