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-rw-r--r--lib/Transforms/Scalar/SimplifyLibCalls.cpp51
1 files changed, 1 insertions, 50 deletions
diff --git a/lib/Transforms/Scalar/SimplifyLibCalls.cpp b/lib/Transforms/Scalar/SimplifyLibCalls.cpp
index 3f39df9456..4d54e13c77 100644
--- a/lib/Transforms/Scalar/SimplifyLibCalls.cpp
+++ b/lib/Transforms/Scalar/SimplifyLibCalls.cpp
@@ -105,54 +105,6 @@ static bool CallHasFloatingPointArgument(const CallInst *CI) {
namespace {
//===---------------------------------------===//
-// 'memcmp' Optimizations
-
-struct MemCmpOpt : public LibCallOptimization {
- virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
- FunctionType *FT = Callee->getFunctionType();
- if (FT->getNumParams() != 3 || !FT->getParamType(0)->isPointerTy() ||
- !FT->getParamType(1)->isPointerTy() ||
- !FT->getReturnType()->isIntegerTy(32))
- return 0;
-
- Value *LHS = CI->getArgOperand(0), *RHS = CI->getArgOperand(1);
-
- if (LHS == RHS) // memcmp(s,s,x) -> 0
- return Constant::getNullValue(CI->getType());
-
- // Make sure we have a constant length.
- ConstantInt *LenC = dyn_cast<ConstantInt>(CI->getArgOperand(2));
- if (!LenC) return 0;
- uint64_t Len = LenC->getZExtValue();
-
- if (Len == 0) // memcmp(s1,s2,0) -> 0
- return Constant::getNullValue(CI->getType());
-
- // memcmp(S1,S2,1) -> *(unsigned char*)LHS - *(unsigned char*)RHS
- if (Len == 1) {
- Value *LHSV = B.CreateZExt(B.CreateLoad(CastToCStr(LHS, B), "lhsc"),
- CI->getType(), "lhsv");
- Value *RHSV = B.CreateZExt(B.CreateLoad(CastToCStr(RHS, B), "rhsc"),
- CI->getType(), "rhsv");
- return B.CreateSub(LHSV, RHSV, "chardiff");
- }
-
- // Constant folding: memcmp(x, y, l) -> cnst (all arguments are constant)
- StringRef LHSStr, RHSStr;
- if (getConstantStringInfo(LHS, LHSStr) &&
- getConstantStringInfo(RHS, RHSStr)) {
- // Make sure we're not reading out-of-bounds memory.
- if (Len > LHSStr.size() || Len > RHSStr.size())
- return 0;
- uint64_t Ret = memcmp(LHSStr.data(), RHSStr.data(), Len);
- return ConstantInt::get(CI->getType(), Ret);
- }
-
- return 0;
- }
-};
-
-//===---------------------------------------===//
// 'memcpy' Optimizations
struct MemCpyOpt : public LibCallOptimization {
@@ -887,7 +839,7 @@ namespace {
StringMap<LibCallOptimization*> Optimizations;
// Memory LibCall Optimizations
- MemCmpOpt MemCmp; MemCpyOpt MemCpy; MemMoveOpt MemMove; MemSetOpt MemSet;
+ MemCpyOpt MemCpy; MemMoveOpt MemMove; MemSetOpt MemSet;
// Math Library Optimizations
CosOpt Cos; PowOpt Pow; Exp2Opt Exp2;
UnaryDoubleFPOpt UnaryDoubleFP, UnsafeUnaryDoubleFP;
@@ -954,7 +906,6 @@ void SimplifyLibCalls::AddOpt(LibFunc::Func F1, LibFunc::Func F2,
/// we know.
void SimplifyLibCalls::InitOptimizations() {
// Memory LibCall Optimizations
- Optimizations["memcmp"] = &MemCmp;
AddOpt(LibFunc::memcpy, &MemCpy);
Optimizations["memmove"] = &MemMove;
AddOpt(LibFunc::memset, &MemSet);