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-rw-r--r--lib/Transforms/Scalar/SimplifyLibCalls.cpp247
1 files changed, 0 insertions, 247 deletions
diff --git a/lib/Transforms/Scalar/SimplifyLibCalls.cpp b/lib/Transforms/Scalar/SimplifyLibCalls.cpp
index 7d652dea48..17d07cdb2d 100644
--- a/lib/Transforms/Scalar/SimplifyLibCalls.cpp
+++ b/lib/Transforms/Scalar/SimplifyLibCalls.cpp
@@ -99,243 +99,7 @@ static bool CallHasFloatingPointArgument(const CallInst *CI) {
return false;
}
-/// IsOnlyUsedInEqualityComparison - Return true if it is only used in equality
-/// comparisons with With.
-static bool IsOnlyUsedInEqualityComparison(Value *V, Value *With) {
- for (Value::use_iterator UI = V->use_begin(), E = V->use_end();
- UI != E; ++UI) {
- if (ICmpInst *IC = dyn_cast<ICmpInst>(*UI))
- if (IC->isEquality() && IC->getOperand(1) == With)
- continue;
- // Unknown instruction.
- return false;
- }
- return true;
-}
-
-//===----------------------------------------------------------------------===//
-// String and Memory LibCall Optimizations
-//===----------------------------------------------------------------------===//
-
namespace {
-//===---------------------------------------===//
-// 'strcspn' Optimizations
-
-struct StrCSpnOpt : public LibCallOptimization {
- virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
- FunctionType *FT = Callee->getFunctionType();
- if (FT->getNumParams() != 2 ||
- FT->getParamType(0) != B.getInt8PtrTy() ||
- FT->getParamType(1) != FT->getParamType(0) ||
- !FT->getReturnType()->isIntegerTy())
- return 0;
-
- StringRef S1, S2;
- bool HasS1 = getConstantStringInfo(CI->getArgOperand(0), S1);
- bool HasS2 = getConstantStringInfo(CI->getArgOperand(1), S2);
-
- // strcspn("", s) -> 0
- if (HasS1 && S1.empty())
- return Constant::getNullValue(CI->getType());
-
- // Constant folding.
- if (HasS1 && HasS2) {
- size_t Pos = S1.find_first_of(S2);
- if (Pos == StringRef::npos) Pos = S1.size();
- return ConstantInt::get(CI->getType(), Pos);
- }
-
- // strcspn(s, "") -> strlen(s)
- if (TD && HasS2 && S2.empty())
- return EmitStrLen(CI->getArgOperand(0), B, TD, TLI);
-
- return 0;
- }
-};
-
-//===---------------------------------------===//
-// 'strstr' Optimizations
-
-struct StrStrOpt : public LibCallOptimization {
- virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
- FunctionType *FT = Callee->getFunctionType();
- if (FT->getNumParams() != 2 ||
- !FT->getParamType(0)->isPointerTy() ||
- !FT->getParamType(1)->isPointerTy() ||
- !FT->getReturnType()->isPointerTy())
- return 0;
-
- // fold strstr(x, x) -> x.
- if (CI->getArgOperand(0) == CI->getArgOperand(1))
- return B.CreateBitCast(CI->getArgOperand(0), CI->getType());
-
- // fold strstr(a, b) == a -> strncmp(a, b, strlen(b)) == 0
- if (TD && IsOnlyUsedInEqualityComparison(CI, CI->getArgOperand(0))) {
- Value *StrLen = EmitStrLen(CI->getArgOperand(1), B, TD, TLI);
- if (!StrLen)
- return 0;
- Value *StrNCmp = EmitStrNCmp(CI->getArgOperand(0), CI->getArgOperand(1),
- StrLen, B, TD, TLI);
- if (!StrNCmp)
- return 0;
- for (Value::use_iterator UI = CI->use_begin(), UE = CI->use_end();
- UI != UE; ) {
- ICmpInst *Old = cast<ICmpInst>(*UI++);
- Value *Cmp = B.CreateICmp(Old->getPredicate(), StrNCmp,
- ConstantInt::getNullValue(StrNCmp->getType()),
- "cmp");
- Old->replaceAllUsesWith(Cmp);
- Old->eraseFromParent();
- }
- return CI;
- }
-
- // See if either input string is a constant string.
- StringRef SearchStr, ToFindStr;
- bool HasStr1 = getConstantStringInfo(CI->getArgOperand(0), SearchStr);
- bool HasStr2 = getConstantStringInfo(CI->getArgOperand(1), ToFindStr);
-
- // fold strstr(x, "") -> x.
- if (HasStr2 && ToFindStr.empty())
- return B.CreateBitCast(CI->getArgOperand(0), CI->getType());
-
- // If both strings are known, constant fold it.
- if (HasStr1 && HasStr2) {
- std::string::size_type Offset = SearchStr.find(ToFindStr);
-
- if (Offset == StringRef::npos) // strstr("foo", "bar") -> null
- return Constant::getNullValue(CI->getType());
-
- // strstr("abcd", "bc") -> gep((char*)"abcd", 1)
- Value *Result = CastToCStr(CI->getArgOperand(0), B);
- Result = B.CreateConstInBoundsGEP1_64(Result, Offset, "strstr");
- return B.CreateBitCast(Result, CI->getType());
- }
-
- // fold strstr(x, "y") -> strchr(x, 'y').
- if (HasStr2 && ToFindStr.size() == 1) {
- Value *StrChr= EmitStrChr(CI->getArgOperand(0), ToFindStr[0], B, TD, TLI);
- return StrChr ? B.CreateBitCast(StrChr, CI->getType()) : 0;
- }
- return 0;
- }
-};
-
-
-//===---------------------------------------===//
-// '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 {
- 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)->isPointerTy() ||
- FT->getParamType(2) != TD->getIntPtrType(*Context))
- return 0;
-
- // memcpy(x, y, n) -> llvm.memcpy(x, y, n, 1)
- B.CreateMemCpy(CI->getArgOperand(0), CI->getArgOperand(1),
- CI->getArgOperand(2), 1);
- return CI->getArgOperand(0);
- }
-};
-
-//===---------------------------------------===//
-// 'memmove' Optimizations
-
-struct MemMoveOpt : 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)->isPointerTy() ||
- FT->getParamType(2) != TD->getIntPtrType(*Context))
- return 0;
-
- // memmove(x, y, n) -> llvm.memmove(x, y, n, 1)
- B.CreateMemMove(CI->getArgOperand(0), CI->getArgOperand(1),
- CI->getArgOperand(2), 1);
- return CI->getArgOperand(0);
- }
-};
-
-//===---------------------------------------===//
-// 'memset' Optimizations
-
-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);
- }
-};
-
//===----------------------------------------------------------------------===//
// Math Library Optimizations
//===----------------------------------------------------------------------===//
@@ -1004,9 +768,6 @@ namespace {
TargetLibraryInfo *TLI;
StringMap<LibCallOptimization*> Optimizations;
- // String and Memory LibCall Optimizations
- StrCSpnOpt StrCSpn; StrStrOpt StrStr;
- MemCmpOpt MemCmp; MemCpyOpt MemCpy; MemMoveOpt MemMove; MemSetOpt MemSet;
// Math Library Optimizations
CosOpt Cos; PowOpt Pow; Exp2Opt Exp2;
UnaryDoubleFPOpt UnaryDoubleFP, UnsafeUnaryDoubleFP;
@@ -1072,14 +833,6 @@ void SimplifyLibCalls::AddOpt(LibFunc::Func F1, LibFunc::Func F2,
/// Optimizations - Populate the Optimizations map with all the optimizations
/// we know.
void SimplifyLibCalls::InitOptimizations() {
- // String and Memory LibCall Optimizations
- Optimizations["strcspn"] = &StrCSpn;
- Optimizations["strstr"] = &StrStr;
- Optimizations["memcmp"] = &MemCmp;
- AddOpt(LibFunc::memcpy, &MemCpy);
- Optimizations["memmove"] = &MemMove;
- AddOpt(LibFunc::memset, &MemSet);
-
// Math Library Optimizations
Optimizations["cosf"] = &Cos;
Optimizations["cos"] = &Cos;
generated by cgit v1.2.3-18-g5258 (git 2.32.0) at 2025-07-16 15:22:50 +0000