//===----------------------------------------------------------------------===//
#include "llvm/Transforms/Utils/SimplifyLibCalls.h"
-#include "llvm/DataLayout.h"
#include "llvm/ADT/StringMap.h"
#include "llvm/Analysis/ValueTracking.h"
-#include "llvm/Function.h"
-#include "llvm/IRBuilder.h"
-#include "llvm/LLVMContext.h"
+#include "llvm/IR/DataLayout.h"
+#include "llvm/IR/Function.h"
+#include "llvm/IR/IRBuilder.h"
+#include "llvm/IR/Intrinsics.h"
+#include "llvm/IR/LLVMContext.h"
+#include "llvm/IR/Module.h"
+#include "llvm/Support/Allocator.h"
#include "llvm/Target/TargetLibraryInfo.h"
#include "llvm/Transforms/Utils/BuildLibCalls.h"
Function *Caller;
const DataLayout *TD;
const TargetLibraryInfo *TLI;
+ const LibCallSimplifier *LCS;
LLVMContext* Context;
public:
LibCallOptimization() { }
virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B)
=0;
+ /// ignoreCallingConv - Returns false if this transformation could possibly
+ /// change the calling convention.
+ virtual bool ignoreCallingConv() { return false; }
+
Value *optimizeCall(CallInst *CI, const DataLayout *TD,
- const TargetLibraryInfo *TLI, IRBuilder<> &B) {
+ const TargetLibraryInfo *TLI,
+ const LibCallSimplifier *LCS, IRBuilder<> &B) {
Caller = CI->getParent()->getParent();
this->TD = TD;
this->TLI = TLI;
+ this->LCS = LCS;
if (CI->getCalledFunction())
Context = &CI->getCalledFunction()->getContext();
// We never change the calling convention.
- if (CI->getCallingConv() != llvm::CallingConv::C)
+ if (!ignoreCallingConv() && CI->getCallingConv() != llvm::CallingConv::C)
return NULL;
return callOptimizer(CI->getCalledFunction(), CI, B);
}
};
+//===----------------------------------------------------------------------===//
+// Helper Functions
+//===----------------------------------------------------------------------===//
+
+/// isOnlyUsedInZeroEqualityComparison - Return true if it only matters that the
+/// value is equal or not-equal to zero.
+static bool isOnlyUsedInZeroEqualityComparison(Value *V) {
+ 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())
+ if (Constant *C = dyn_cast<Constant>(IC->getOperand(1)))
+ if (C->isNullValue())
+ continue;
+ // Unknown instruction.
+ return false;
+ }
+ return true;
+}
+
+/// 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;
+}
+
+static bool callHasFloatingPointArgument(const CallInst *CI) {
+ for (CallInst::const_op_iterator it = CI->op_begin(), e = CI->op_end();
+ it != e; ++it) {
+ if ((*it)->getType()->isFloatingPointTy())
+ return true;
+ }
+ return false;
+}
+
//===----------------------------------------------------------------------===//
// Fortified Library Call Optimizations
//===----------------------------------------------------------------------===//
FT->getParamType(2) != TD->getIntPtrType(Context))
return 0;
+ Value *Dst = CI->getArgOperand(0), *Src = CI->getArgOperand(1);
+ if (Dst == Src) // __strcpy_chk(x,x) -> x
+ return Src;
+
+ // If a) we don't have any length information, or b) we know this will
+ // fit then just lower to a plain strcpy. Otherwise we'll keep our
+ // strcpy_chk call which may fail at runtime if the size is too long.
+ // TODO: It might be nice to get a maximum length out of the possible
+ // string lengths for varying.
+ if (isFoldable(2, 1, true)) {
+ Value *Ret = EmitStrCpy(Dst, Src, B, TD, TLI, Name.substr(2, 6));
+ return Ret;
+ } else {
+ // Maybe we can stil fold __strcpy_chk to __memcpy_chk.
+ uint64_t Len = GetStringLength(Src);
+ if (Len == 0) return 0;
+
+ // This optimization require DataLayout.
+ if (!TD) return 0;
+
+ Value *Ret =
+ EmitMemCpyChk(Dst, Src,
+ ConstantInt::get(TD->getIntPtrType(Context), Len),
+ CI->getArgOperand(2), B, TD, TLI);
+ return Ret;
+ }
+ return 0;
+ }
+};
+
+struct StpCpyChkOpt : public InstFortifiedLibCallOptimization {
+ virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+ this->CI = CI;
+ StringRef Name = Callee->getName();
+ FunctionType *FT = Callee->getFunctionType();
+ LLVMContext &Context = CI->getParent()->getContext();
+
+ // Check if this has the right signature.
+ if (FT->getNumParams() != 3 ||
+ FT->getReturnType() != FT->getParamType(0) ||
+ FT->getParamType(0) != FT->getParamType(1) ||
+ FT->getParamType(0) != Type::getInt8PtrTy(Context) ||
+ FT->getParamType(2) != TD->getIntPtrType(FT->getParamType(0)))
+ return 0;
+
+ Value *Dst = CI->getArgOperand(0), *Src = CI->getArgOperand(1);
+ if (Dst == Src) { // stpcpy(x,x) -> x+strlen(x)
+ Value *StrLen = EmitStrLen(Src, B, TD, TLI);
+ return StrLen ? B.CreateInBoundsGEP(Dst, StrLen) : 0;
+ }
+
// If a) we don't have any length information, or b) we know this will
- // fit then just lower to a plain st[rp]cpy. Otherwise we'll keep our
- // st[rp]cpy_chk call which may fail at runtime if the size is too long.
+ // fit then just lower to a plain stpcpy. Otherwise we'll keep our
+ // stpcpy_chk call which may fail at runtime if the size is too long.
// TODO: It might be nice to get a maximum length out of the possible
// string lengths for varying.
if (isFoldable(2, 1, true)) {
- Value *Ret = EmitStrCpy(CI->getArgOperand(0), CI->getArgOperand(1), B, TD,
- TLI, Name.substr(2, 6));
+ Value *Ret = EmitStrCpy(Dst, Src, B, TD, TLI, Name.substr(2, 6));
return Ret;
+ } else {
+ // Maybe we can stil fold __stpcpy_chk to __memcpy_chk.
+ uint64_t Len = GetStringLength(Src);
+ if (Len == 0) return 0;
+
+ // This optimization require DataLayout.
+ if (!TD) return 0;
+
+ Type *PT = FT->getParamType(0);
+ Value *LenV = ConstantInt::get(TD->getIntPtrType(PT), Len);
+ Value *DstEnd = B.CreateGEP(Dst,
+ ConstantInt::get(TD->getIntPtrType(PT),
+ Len - 1));
+ if (!EmitMemCpyChk(Dst, Src, LenV, CI->getArgOperand(2), B, TD, TLI))
+ return 0;
+ return DstEnd;
}
return 0;
}
}
};
-} // End anonymous namespace.
+struct StrCmpOpt : public LibCallOptimization {
+ virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+ // Verify the "strcmp" function prototype.
+ FunctionType *FT = Callee->getFunctionType();
+ if (FT->getNumParams() != 2 ||
+ !FT->getReturnType()->isIntegerTy(32) ||
+ FT->getParamType(0) != FT->getParamType(1) ||
+ FT->getParamType(0) != B.getInt8PtrTy())
+ return 0;
-namespace llvm {
+ Value *Str1P = CI->getArgOperand(0), *Str2P = CI->getArgOperand(1);
+ if (Str1P == Str2P) // strcmp(x,x) -> 0
+ return ConstantInt::get(CI->getType(), 0);
-class LibCallSimplifierImpl {
- const DataLayout *TD;
- const TargetLibraryInfo *TLI;
- StringMap<LibCallOptimization*> Optimizations;
+ StringRef Str1, Str2;
+ bool HasStr1 = getConstantStringInfo(Str1P, Str1);
+ bool HasStr2 = getConstantStringInfo(Str2P, Str2);
- // Fortified library call optimizations.
- MemCpyChkOpt MemCpyChk;
- MemMoveChkOpt MemMoveChk;
- MemSetChkOpt MemSetChk;
- StrCpyChkOpt StrCpyChk;
- StrNCpyChkOpt StrNCpyChk;
+ // strcmp(x, y) -> cnst (if both x and y are constant strings)
+ if (HasStr1 && HasStr2)
+ return ConstantInt::get(CI->getType(), Str1.compare(Str2));
- // String and memory library call optimizations.
- StrCatOpt StrCat;
- StrNCatOpt StrNCat;
- StrChrOpt StrChr;
- StrRChrOpt StrRChr;
+ if (HasStr1 && Str1.empty()) // strcmp("", x) -> -*x
+ return B.CreateNeg(B.CreateZExt(B.CreateLoad(Str2P, "strcmpload"),
+ CI->getType()));
- void initOptimizations();
-public:
- LibCallSimplifierImpl(const DataLayout *TD, const TargetLibraryInfo *TLI) {
- this->TD = TD;
- this->TLI = TLI;
+ if (HasStr2 && Str2.empty()) // strcmp(x,"") -> *x
+ return B.CreateZExt(B.CreateLoad(Str1P, "strcmpload"), CI->getType());
+
+ // strcmp(P, "x") -> memcmp(P, "x", 2)
+ uint64_t Len1 = GetStringLength(Str1P);
+ uint64_t Len2 = GetStringLength(Str2P);
+ if (Len1 && Len2) {
+ // These optimizations require DataLayout.
+ if (!TD) return 0;
+
+ return EmitMemCmp(Str1P, Str2P,
+ ConstantInt::get(TD->getIntPtrType(*Context),
+ std::min(Len1, Len2)), B, TD, TLI);
+ }
+
+ return 0;
}
+};
- Value *optimizeCall(CallInst *CI);
+struct StrNCmpOpt : public LibCallOptimization {
+ virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+ // Verify the "strncmp" function prototype.
+ FunctionType *FT = Callee->getFunctionType();
+ if (FT->getNumParams() != 3 ||
+ !FT->getReturnType()->isIntegerTy(32) ||
+ FT->getParamType(0) != FT->getParamType(1) ||
+ FT->getParamType(0) != B.getInt8PtrTy() ||
+ !FT->getParamType(2)->isIntegerTy())
+ return 0;
+
+ Value *Str1P = CI->getArgOperand(0), *Str2P = CI->getArgOperand(1);
+ if (Str1P == Str2P) // strncmp(x,x,n) -> 0
+ return ConstantInt::get(CI->getType(), 0);
+
+ // Get the length argument if it is constant.
+ uint64_t Length;
+ if (ConstantInt *LengthArg = dyn_cast<ConstantInt>(CI->getArgOperand(2)))
+ Length = LengthArg->getZExtValue();
+ else
+ return 0;
+
+ if (Length == 0) // strncmp(x,y,0) -> 0
+ return ConstantInt::get(CI->getType(), 0);
+
+ if (TD && Length == 1) // strncmp(x,y,1) -> memcmp(x,y,1)
+ return EmitMemCmp(Str1P, Str2P, CI->getArgOperand(2), B, TD, TLI);
+
+ StringRef Str1, Str2;
+ bool HasStr1 = getConstantStringInfo(Str1P, Str1);
+ bool HasStr2 = getConstantStringInfo(Str2P, Str2);
+
+ // strncmp(x, y) -> cnst (if both x and y are constant strings)
+ if (HasStr1 && HasStr2) {
+ StringRef SubStr1 = Str1.substr(0, Length);
+ StringRef SubStr2 = Str2.substr(0, Length);
+ return ConstantInt::get(CI->getType(), SubStr1.compare(SubStr2));
+ }
+
+ if (HasStr1 && Str1.empty()) // strncmp("", x, n) -> -*x
+ return B.CreateNeg(B.CreateZExt(B.CreateLoad(Str2P, "strcmpload"),
+ CI->getType()));
+
+ if (HasStr2 && Str2.empty()) // strncmp(x, "", n) -> *x
+ return B.CreateZExt(B.CreateLoad(Str1P, "strcmpload"), CI->getType());
+
+ return 0;
+ }
};
-void LibCallSimplifierImpl::initOptimizations() {
- // Fortified library call optimizations.
- Optimizations["__memcpy_chk"] = &MemCpyChk;
- Optimizations["__memmove_chk"] = &MemMoveChk;
- Optimizations["__memset_chk"] = &MemSetChk;
- Optimizations["__strcpy_chk"] = &StrCpyChk;
- Optimizations["__stpcpy_chk"] = &StrCpyChk;
- Optimizations["__strncpy_chk"] = &StrNCpyChk;
- Optimizations["__stpncpy_chk"] = &StrNCpyChk;
+struct StrCpyOpt : public LibCallOptimization {
+ virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+ // Verify the "strcpy" function prototype.
+ FunctionType *FT = Callee->getFunctionType();
+ if (FT->getNumParams() != 2 ||
+ FT->getReturnType() != FT->getParamType(0) ||
+ FT->getParamType(0) != FT->getParamType(1) ||
+ FT->getParamType(0) != B.getInt8PtrTy())
+ return 0;
- // String and memory library call optimizations.
- Optimizations["strcat"] = &StrCat;
- Optimizations["strncat"] = &StrNCat;
- Optimizations["strchr"] = &StrChr;
- Optimizations["strrchr"] = &StrRChr;
-}
+ Value *Dst = CI->getArgOperand(0), *Src = CI->getArgOperand(1);
+ if (Dst == Src) // strcpy(x,x) -> x
+ return Src;
-Value *LibCallSimplifierImpl::optimizeCall(CallInst *CI) {
- if (Optimizations.empty())
- initOptimizations();
+ // These optimizations require DataLayout.
+ if (!TD) return 0;
- Function *Callee = CI->getCalledFunction();
- LibCallOptimization *LCO = Optimizations.lookup(Callee->getName());
- if (LCO) {
- IRBuilder<> Builder(CI);
- return LCO->optimizeCall(CI, TD, TLI, Builder);
+ // See if we can get the length of the input string.
+ uint64_t Len = GetStringLength(Src);
+ if (Len == 0) return 0;
+
+ // We have enough information to now generate the memcpy call to do the
+ // copy for us. Make a memcpy to copy the nul byte with align = 1.
+ B.CreateMemCpy(Dst, Src,
+ ConstantInt::get(TD->getIntPtrType(*Context), Len), 1);
+ return Dst;
}
- return 0;
-}
+};
-LibCallSimplifier::LibCallSimplifier(const DataLayout *TD,
- const TargetLibraryInfo *TLI) {
- Impl = new LibCallSimplifierImpl(TD, TLI);
-}
+struct StpCpyOpt: public LibCallOptimization {
+ virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+ // Verify the "stpcpy" function prototype.
+ FunctionType *FT = Callee->getFunctionType();
+ if (FT->getNumParams() != 2 ||
+ FT->getReturnType() != FT->getParamType(0) ||
+ FT->getParamType(0) != FT->getParamType(1) ||
+ FT->getParamType(0) != B.getInt8PtrTy())
+ return 0;
-LibCallSimplifier::~LibCallSimplifier() {
- delete Impl;
-}
+ // These optimizations require DataLayout.
+ if (!TD) return 0;
-Value *LibCallSimplifier::optimizeCall(CallInst *CI) {
- return Impl->optimizeCall(CI);
+ Value *Dst = CI->getArgOperand(0), *Src = CI->getArgOperand(1);
+ if (Dst == Src) { // stpcpy(x,x) -> x+strlen(x)
+ Value *StrLen = EmitStrLen(Src, B, TD, TLI);
+ return StrLen ? B.CreateInBoundsGEP(Dst, StrLen) : 0;
+ }
+
+ // See if we can get the length of the input string.
+ uint64_t Len = GetStringLength(Src);
+ if (Len == 0) return 0;
+
+ Type *PT = FT->getParamType(0);
+ Value *LenV = ConstantInt::get(TD->getIntPtrType(PT), Len);
+ Value *DstEnd = B.CreateGEP(Dst,
+ ConstantInt::get(TD->getIntPtrType(PT),
+ Len - 1));
+
+ // We have enough information to now generate the memcpy call to do the
+ // copy for us. Make a memcpy to copy the nul byte with align = 1.
+ B.CreateMemCpy(Dst, Src, LenV, 1);
+ return DstEnd;
+ }
+};
+
+struct StrNCpyOpt : public LibCallOptimization {
+ virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+ FunctionType *FT = Callee->getFunctionType();
+ if (FT->getNumParams() != 3 || FT->getReturnType() != FT->getParamType(0) ||
+ FT->getParamType(0) != FT->getParamType(1) ||
+ FT->getParamType(0) != B.getInt8PtrTy() ||
+ !FT->getParamType(2)->isIntegerTy())
+ return 0;
+
+ Value *Dst = CI->getArgOperand(0);
+ Value *Src = CI->getArgOperand(1);
+ Value *LenOp = CI->getArgOperand(2);
+
+ // See if we can get the length of the input string.
+ uint64_t SrcLen = GetStringLength(Src);
+ if (SrcLen == 0) return 0;
+ --SrcLen;
+
+ if (SrcLen == 0) {
+ // strncpy(x, "", y) -> memset(x, '\0', y, 1)
+ B.CreateMemSet(Dst, B.getInt8('\0'), LenOp, 1);
+ return Dst;
+ }
+
+ uint64_t Len;
+ if (ConstantInt *LengthArg = dyn_cast<ConstantInt>(LenOp))
+ Len = LengthArg->getZExtValue();
+ else
+ return 0;
+
+ if (Len == 0) return Dst; // strncpy(x, y, 0) -> x
+
+ // These optimizations require DataLayout.
+ if (!TD) return 0;
+
+ // Let strncpy handle the zero padding
+ if (Len > SrcLen+1) return 0;
+
+ Type *PT = FT->getParamType(0);
+ // strncpy(x, s, c) -> memcpy(x, s, c, 1) [s and c are constant]
+ B.CreateMemCpy(Dst, Src,
+ ConstantInt::get(TD->getIntPtrType(PT), Len), 1);
+
+ return Dst;
+ }
+};
+
+struct StrLenOpt : public LibCallOptimization {
+ virtual bool ignoreCallingConv() { return true; }
+ virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+ FunctionType *FT = Callee->getFunctionType();
+ if (FT->getNumParams() != 1 ||
+ FT->getParamType(0) != B.getInt8PtrTy() ||
+ !FT->getReturnType()->isIntegerTy())
+ return 0;
+
+ Value *Src = CI->getArgOperand(0);
+
+ // Constant folding: strlen("xyz") -> 3
+ if (uint64_t Len = GetStringLength(Src))
+ return ConstantInt::get(CI->getType(), Len-1);
+
+ // strlen(x) != 0 --> *x != 0
+ // strlen(x) == 0 --> *x == 0
+ if (isOnlyUsedInZeroEqualityComparison(CI))
+ return B.CreateZExt(B.CreateLoad(Src, "strlenfirst"), CI->getType());
+ return 0;
+ }
+};
+
+struct StrPBrkOpt : 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() != FT->getParamType(0))
+ return 0;
+
+ StringRef S1, S2;
+ bool HasS1 = getConstantStringInfo(CI->getArgOperand(0), S1);
+ bool HasS2 = getConstantStringInfo(CI->getArgOperand(1), S2);
+
+ // strpbrk(s, "") -> NULL
+ // strpbrk("", s) -> NULL
+ if ((HasS1 && S1.empty()) || (HasS2 && S2.empty()))
+ return Constant::getNullValue(CI->getType());
+
+ // Constant folding.
+ if (HasS1 && HasS2) {
+ size_t I = S1.find_first_of(S2);
+ if (I == std::string::npos) // No match.
+ return Constant::getNullValue(CI->getType());
+
+ return B.CreateGEP(CI->getArgOperand(0), B.getInt64(I), "strpbrk");
+ }
+
+ // strpbrk(s, "a") -> strchr(s, 'a')
+ if (TD && HasS2 && S2.size() == 1)
+ return EmitStrChr(CI->getArgOperand(0), S2[0], B, TD, TLI);
+
+ return 0;
+ }
+};
+
+struct StrToOpt : public LibCallOptimization {
+ virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+ FunctionType *FT = Callee->getFunctionType();
+ if ((FT->getNumParams() != 2 && FT->getNumParams() != 3) ||
+ !FT->getParamType(0)->isPointerTy() ||
+ !FT->getParamType(1)->isPointerTy())
+ return 0;
+
+ Value *EndPtr = CI->getArgOperand(1);
+ if (isa<ConstantPointerNull>(EndPtr)) {
+ // With a null EndPtr, this function won't capture the main argument.
+ // It would be readonly too, except that it still may write to errno.
+ CI->addAttribute(1, Attribute::NoCapture);
+ }
+
+ return 0;
+ }
+};
+
+struct StrSpnOpt : 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);
+
+ // strspn(s, "") -> 0
+ // strspn("", s) -> 0
+ if ((HasS1 && S1.empty()) || (HasS2 && S2.empty()))
+ return Constant::getNullValue(CI->getType());
+
+ // Constant folding.
+ if (HasS1 && HasS2) {
+ size_t Pos = S1.find_first_not_of(S2);
+ if (Pos == StringRef::npos) Pos = S1.size();
+ return ConstantInt::get(CI->getType(), Pos);
+ }
+
+ return 0;
+ }
+};
+
+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;
+ }
+};
+
+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");
+ LCS->replaceAllUsesWith(Old, Cmp);
+ }
+ 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;
+ }
+};
+
+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;
+ // Fold the memcmp and normalize the result. This way we get consistent
+ // results across multiple platforms.
+ uint64_t Ret = 0;
+ int Cmp = memcmp(LHSStr.data(), RHSStr.data(), Len);
+ if (Cmp < 0)
+ Ret = -1;
+ else if (Cmp > 0)
+ Ret = 1;
+ return ConstantInt::get(CI->getType(), Ret);
+ }
+
+ return 0;
+ }
+};
+
+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);
+ }
+};
+
+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);
+ }
+};
+
+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
+//===----------------------------------------------------------------------===//
+
+//===----------------------------------------------------------------------===//
+// Double -> Float Shrinking Optimizations for Unary Functions like 'floor'
+
+struct UnaryDoubleFPOpt : public LibCallOptimization {
+ bool CheckRetType;
+ UnaryDoubleFPOpt(bool CheckReturnType): CheckRetType(CheckReturnType) {}
+ virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+ FunctionType *FT = Callee->getFunctionType();
+ if (FT->getNumParams() != 1 || !FT->getReturnType()->isDoubleTy() ||
+ !FT->getParamType(0)->isDoubleTy())
+ return 0;
+
+ if (CheckRetType) {
+ // Check if all the uses for function like 'sin' are converted to float.
+ for (Value::use_iterator UseI = CI->use_begin(); UseI != CI->use_end();
+ ++UseI) {
+ FPTruncInst *Cast = dyn_cast<FPTruncInst>(*UseI);
+ if (Cast == 0 || !Cast->getType()->isFloatTy())
+ return 0;
+ }
+ }
+
+ // If this is something like 'floor((double)floatval)', convert to floorf.
+ FPExtInst *Cast = dyn_cast<FPExtInst>(CI->getArgOperand(0));
+ if (Cast == 0 || !Cast->getOperand(0)->getType()->isFloatTy())
+ return 0;
+
+ // floor((double)floatval) -> (double)floorf(floatval)
+ Value *V = Cast->getOperand(0);
+ V = EmitUnaryFloatFnCall(V, Callee->getName(), B, Callee->getAttributes());
+ return B.CreateFPExt(V, B.getDoubleTy());
+ }
+};
+
+struct UnsafeFPLibCallOptimization : public LibCallOptimization {
+ bool UnsafeFPShrink;
+ UnsafeFPLibCallOptimization(bool UnsafeFPShrink) {
+ this->UnsafeFPShrink = UnsafeFPShrink;
+ }
+};
+
+struct CosOpt : public UnsafeFPLibCallOptimization {
+ CosOpt(bool UnsafeFPShrink) : UnsafeFPLibCallOptimization(UnsafeFPShrink) {}
+ virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+ Value *Ret = NULL;
+ if (UnsafeFPShrink && Callee->getName() == "cos" &&
+ TLI->has(LibFunc::cosf)) {
+ UnaryDoubleFPOpt UnsafeUnaryDoubleFP(true);
+ Ret = UnsafeUnaryDoubleFP.callOptimizer(Callee, CI, B);
+ }
+
+ FunctionType *FT = Callee->getFunctionType();
+ // Just make sure this has 1 argument of FP type, which matches the
+ // result type.
+ if (FT->getNumParams() != 1 || FT->getReturnType() != FT->getParamType(0) ||
+ !FT->getParamType(0)->isFloatingPointTy())
+ return Ret;
+
+ // cos(-x) -> cos(x)
+ Value *Op1 = CI->getArgOperand(0);
+ if (BinaryOperator::isFNeg(Op1)) {
+ BinaryOperator *BinExpr = cast<BinaryOperator>(Op1);
+ return B.CreateCall(Callee, BinExpr->getOperand(1), "cos");
+ }
+ return Ret;
+ }
+};
+
+struct PowOpt : public UnsafeFPLibCallOptimization {
+ PowOpt(bool UnsafeFPShrink) : UnsafeFPLibCallOptimization(UnsafeFPShrink) {}
+ virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+ Value *Ret = NULL;
+ if (UnsafeFPShrink && Callee->getName() == "pow" &&
+ TLI->has(LibFunc::powf)) {
+ UnaryDoubleFPOpt UnsafeUnaryDoubleFP(true);
+ Ret = UnsafeUnaryDoubleFP.callOptimizer(Callee, CI, B);
+ }
+
+ FunctionType *FT = Callee->getFunctionType();
+ // Just make sure this has 2 arguments of the same FP type, which match the
+ // result type.
+ if (FT->getNumParams() != 2 || FT->getReturnType() != FT->getParamType(0) ||
+ FT->getParamType(0) != FT->getParamType(1) ||
+ !FT->getParamType(0)->isFloatingPointTy())
+ return Ret;
+
+ Value *Op1 = CI->getArgOperand(0), *Op2 = CI->getArgOperand(1);
+ if (ConstantFP *Op1C = dyn_cast<ConstantFP>(Op1)) {
+ if (Op1C->isExactlyValue(1.0)) // pow(1.0, x) -> 1.0
+ return Op1C;
+ if (Op1C->isExactlyValue(2.0)) // pow(2.0, x) -> exp2(x)
+ return EmitUnaryFloatFnCall(Op2, "exp2", B, Callee->getAttributes());
+ }
+
+ ConstantFP *Op2C = dyn_cast<ConstantFP>(Op2);
+ if (Op2C == 0) return Ret;
+
+ if (Op2C->getValueAPF().isZero()) // pow(x, 0.0) -> 1.0
+ return ConstantFP::get(CI->getType(), 1.0);
+
+ if (Op2C->isExactlyValue(0.5)) {
+ // Expand pow(x, 0.5) to (x == -infinity ? +infinity : fabs(sqrt(x))).
+ // This is faster than calling pow, and still handles negative zero
+ // and negative infinity correctly.
+ // TODO: In fast-math mode, this could be just sqrt(x).
+ // TODO: In finite-only mode, this could be just fabs(sqrt(x)).
+ Value *Inf = ConstantFP::getInfinity(CI->getType());
+ Value *NegInf = ConstantFP::getInfinity(CI->getType(), true);
+ Value *Sqrt = EmitUnaryFloatFnCall(Op1, "sqrt", B,
+ Callee->getAttributes());
+ Value *FAbs = EmitUnaryFloatFnCall(Sqrt, "fabs", B,
+ Callee->getAttributes());
+ Value *FCmp = B.CreateFCmpOEQ(Op1, NegInf);
+ Value *Sel = B.CreateSelect(FCmp, Inf, FAbs);
+ return Sel;
+ }
+
+ if (Op2C->isExactlyValue(1.0)) // pow(x, 1.0) -> x
+ return Op1;
+ if (Op2C->isExactlyValue(2.0)) // pow(x, 2.0) -> x*x
+ return B.CreateFMul(Op1, Op1, "pow2");
+ if (Op2C->isExactlyValue(-1.0)) // pow(x, -1.0) -> 1.0/x
+ return B.CreateFDiv(ConstantFP::get(CI->getType(), 1.0),
+ Op1, "powrecip");
+ return 0;
+ }
+};
+
+struct Exp2Opt : public UnsafeFPLibCallOptimization {
+ Exp2Opt(bool UnsafeFPShrink) : UnsafeFPLibCallOptimization(UnsafeFPShrink) {}
+ virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+ Value *Ret = NULL;
+ if (UnsafeFPShrink && Callee->getName() == "exp2" &&
+ TLI->has(LibFunc::exp2)) {
+ UnaryDoubleFPOpt UnsafeUnaryDoubleFP(true);
+ Ret = UnsafeUnaryDoubleFP.callOptimizer(Callee, CI, B);
+ }
+
+ FunctionType *FT = Callee->getFunctionType();
+ // Just make sure this has 1 argument of FP type, which matches the
+ // result type.
+ if (FT->getNumParams() != 1 || FT->getReturnType() != FT->getParamType(0) ||
+ !FT->getParamType(0)->isFloatingPointTy())
+ return Ret;
+
+ Value *Op = CI->getArgOperand(0);
+ // Turn exp2(sitofp(x)) -> ldexp(1.0, sext(x)) if sizeof(x) <= 32
+ // Turn exp2(uitofp(x)) -> ldexp(1.0, zext(x)) if sizeof(x) < 32
+ Value *LdExpArg = 0;
+ if (SIToFPInst *OpC = dyn_cast<SIToFPInst>(Op)) {
+ if (OpC->getOperand(0)->getType()->getPrimitiveSizeInBits() <= 32)
+ LdExpArg = B.CreateSExt(OpC->getOperand(0), B.getInt32Ty());
+ } else if (UIToFPInst *OpC = dyn_cast<UIToFPInst>(Op)) {
+ if (OpC->getOperand(0)->getType()->getPrimitiveSizeInBits() < 32)
+ LdExpArg = B.CreateZExt(OpC->getOperand(0), B.getInt32Ty());
+ }
+
+ if (LdExpArg) {
+ const char *Name;
+ if (Op->getType()->isFloatTy())
+ Name = "ldexpf";
+ else if (Op->getType()->isDoubleTy())
+ Name = "ldexp";
+ else
+ Name = "ldexpl";
+
+ Constant *One = ConstantFP::get(*Context, APFloat(1.0f));
+ if (!Op->getType()->isFloatTy())
+ One = ConstantExpr::getFPExtend(One, Op->getType());
+
+ Module *M = Caller->getParent();
+ Value *Callee = M->getOrInsertFunction(Name, Op->getType(),
+ Op->getType(),
+ B.getInt32Ty(), NULL);
+ CallInst *CI = B.CreateCall2(Callee, One, LdExpArg);
+ if (const Function *F = dyn_cast<Function>(Callee->stripPointerCasts()))
+ CI->setCallingConv(F->getCallingConv());
+
+ return CI;
+ }
+ return Ret;
+ }
+};
+
+//===----------------------------------------------------------------------===//
+// Integer Library Call Optimizations
+//===----------------------------------------------------------------------===//
+
+struct FFSOpt : public LibCallOptimization {
+ virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+ FunctionType *FT = Callee->getFunctionType();
+ // Just make sure this has 2 arguments of the same FP type, which match the
+ // result type.
+ if (FT->getNumParams() != 1 ||
+ !FT->getReturnType()->isIntegerTy(32) ||
+ !FT->getParamType(0)->isIntegerTy())
+ return 0;
+
+ Value *Op = CI->getArgOperand(0);
+
+ // Constant fold.
+ if (ConstantInt *CI = dyn_cast<ConstantInt>(Op)) {
+ if (CI->isZero()) // ffs(0) -> 0.
+ return B.getInt32(0);
+ // ffs(c) -> cttz(c)+1
+ return B.getInt32(CI->getValue().countTrailingZeros() + 1);
+ }
+
+ // ffs(x) -> x != 0 ? (i32)llvm.cttz(x)+1 : 0
+ Type *ArgType = Op->getType();
+ Value *F = Intrinsic::getDeclaration(Callee->getParent(),
+ Intrinsic::cttz, ArgType);
+ Value *V = B.CreateCall2(F, Op, B.getFalse(), "cttz");
+ V = B.CreateAdd(V, ConstantInt::get(V->getType(), 1));
+ V = B.CreateIntCast(V, B.getInt32Ty(), false);
+
+ Value *Cond = B.CreateICmpNE(Op, Constant::getNullValue(ArgType));
+ return B.CreateSelect(Cond, V, B.getInt32(0));
+ }
+};
+
+struct AbsOpt : public LibCallOptimization {
+ virtual bool ignoreCallingConv() { return true; }
+ virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+ FunctionType *FT = Callee->getFunctionType();
+ // We require integer(integer) where the types agree.
+ if (FT->getNumParams() != 1 || !FT->getReturnType()->isIntegerTy() ||
+ FT->getParamType(0) != FT->getReturnType())
+ return 0;
+
+ // abs(x) -> x >s -1 ? x : -x
+ Value *Op = CI->getArgOperand(0);
+ Value *Pos = B.CreateICmpSGT(Op, Constant::getAllOnesValue(Op->getType()),
+ "ispos");
+ Value *Neg = B.CreateNeg(Op, "neg");
+ return B.CreateSelect(Pos, Op, Neg);
+ }
+};
+
+struct IsDigitOpt : public LibCallOptimization {
+ virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+ FunctionType *FT = Callee->getFunctionType();
+ // We require integer(i32)
+ if (FT->getNumParams() != 1 || !FT->getReturnType()->isIntegerTy() ||
+ !FT->getParamType(0)->isIntegerTy(32))
+ return 0;
+
+ // isdigit(c) -> (c-'0') <u 10
+ Value *Op = CI->getArgOperand(0);
+ Op = B.CreateSub(Op, B.getInt32('0'), "isdigittmp");
+ Op = B.CreateICmpULT(Op, B.getInt32(10), "isdigit");
+ return B.CreateZExt(Op, CI->getType());
+ }
+};
+
+struct IsAsciiOpt : public LibCallOptimization {
+ virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+ FunctionType *FT = Callee->getFunctionType();
+ // We require integer(i32)
+ if (FT->getNumParams() != 1 || !FT->getReturnType()->isIntegerTy() ||
+ !FT->getParamType(0)->isIntegerTy(32))
+ return 0;
+
+ // isascii(c) -> c <u 128
+ Value *Op = CI->getArgOperand(0);
+ Op = B.CreateICmpULT(Op, B.getInt32(128), "isascii");
+ return B.CreateZExt(Op, CI->getType());
+ }
+};
+
+struct ToAsciiOpt : public LibCallOptimization {
+ virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+ FunctionType *FT = Callee->getFunctionType();
+ // We require i32(i32)
+ if (FT->getNumParams() != 1 || FT->getReturnType() != FT->getParamType(0) ||
+ !FT->getParamType(0)->isIntegerTy(32))
+ return 0;
+
+ // toascii(c) -> c & 0x7f
+ return B.CreateAnd(CI->getArgOperand(0),
+ ConstantInt::get(CI->getType(),0x7F));
+ }
+};
+
+//===----------------------------------------------------------------------===//
+// Formatting and IO Library Call Optimizations
+//===----------------------------------------------------------------------===//
+
+struct PrintFOpt : public LibCallOptimization {
+ Value *optimizeFixedFormatString(Function *Callee, CallInst *CI,
+ IRBuilder<> &B) {
+ // Check for a fixed format string.
+ StringRef FormatStr;
+ if (!getConstantStringInfo(CI->getArgOperand(0), FormatStr))
+ return 0;
+
+ // Empty format string -> noop.
+ if (FormatStr.empty()) // Tolerate printf's declared void.
+ return CI->use_empty() ? (Value*)CI :
+ ConstantInt::get(CI->getType(), 0);
+
+ // Do not do any of the following transformations if the printf return value
+ // is used, in general the printf return value is not compatible with either
+ // putchar() or puts().
+ if (!CI->use_empty())
+ return 0;
+
+ // printf("x") -> putchar('x'), even for '%'.
+ if (FormatStr.size() == 1) {
+ Value *Res = EmitPutChar(B.getInt32(FormatStr[0]), B, TD, TLI);
+ if (CI->use_empty() || !Res) return Res;
+ return B.CreateIntCast(Res, CI->getType(), true);
+ }
+
+ // printf("foo\n") --> puts("foo")
+ if (FormatStr[FormatStr.size()-1] == '\n' &&
+ FormatStr.find('%') == std::string::npos) { // no format characters.
+ // Create a string literal with no \n on it. We expect the constant merge
+ // pass to be run after this pass, to merge duplicate strings.
+ FormatStr = FormatStr.drop_back();
+ Value *GV = B.CreateGlobalString(FormatStr, "str");
+ Value *NewCI = EmitPutS(GV, B, TD, TLI);
+ return (CI->use_empty() || !NewCI) ?
+ NewCI :
+ ConstantInt::get(CI->getType(), FormatStr.size()+1);
+ }
+
+ // Optimize specific format strings.
+ // printf("%c", chr) --> putchar(chr)
+ if (FormatStr == "%c" && CI->getNumArgOperands() > 1 &&
+ CI->getArgOperand(1)->getType()->isIntegerTy()) {
+ Value *Res = EmitPutChar(CI->getArgOperand(1), B, TD, TLI);
+
+ if (CI->use_empty() || !Res) return Res;
+ return B.CreateIntCast(Res, CI->getType(), true);
+ }
+
+ // printf("%s\n", str) --> puts(str)
+ if (FormatStr == "%s\n" && CI->getNumArgOperands() > 1 &&
+ CI->getArgOperand(1)->getType()->isPointerTy()) {
+ return EmitPutS(CI->getArgOperand(1), B, TD, TLI);
+ }
+ return 0;
+ }
+
+ virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+ // Require one fixed pointer argument and an integer/void result.
+ FunctionType *FT = Callee->getFunctionType();
+ if (FT->getNumParams() < 1 || !FT->getParamType(0)->isPointerTy() ||
+ !(FT->getReturnType()->isIntegerTy() ||
+ FT->getReturnType()->isVoidTy()))
+ return 0;
+
+ if (Value *V = optimizeFixedFormatString(Callee, CI, B)) {
+ return V;
+ }
+
+ // printf(format, ...) -> iprintf(format, ...) if no floating point
+ // arguments.
+ if (TLI->has(LibFunc::iprintf) && !callHasFloatingPointArgument(CI)) {
+ Module *M = B.GetInsertBlock()->getParent()->getParent();
+ Constant *IPrintFFn =
+ M->getOrInsertFunction("iprintf", FT, Callee->getAttributes());
+ CallInst *New = cast<CallInst>(CI->clone());
+ New->setCalledFunction(IPrintFFn);
+ B.Insert(New);
+ return New;
+ }
+ return 0;
+ }
+};
+
+struct SPrintFOpt : public LibCallOptimization {
+ Value *OptimizeFixedFormatString(Function *Callee, CallInst *CI,
+ IRBuilder<> &B) {
+ // Check for a fixed format string.
+ StringRef FormatStr;
+ if (!getConstantStringInfo(CI->getArgOperand(1), FormatStr))
+ return 0;
+
+ // If we just have a format string (nothing else crazy) transform it.
+ if (CI->getNumArgOperands() == 2) {
+ // Make sure there's no % in the constant array. We could try to handle
+ // %% -> % in the future if we cared.
+ for (unsigned i = 0, e = FormatStr.size(); i != e; ++i)
+ if (FormatStr[i] == '%')
+ return 0; // we found a format specifier, bail out.
+
+ // These optimizations require DataLayout.
+ if (!TD) return 0;
+
+ // sprintf(str, fmt) -> llvm.memcpy(str, fmt, strlen(fmt)+1, 1)
+ B.CreateMemCpy(CI->getArgOperand(0), CI->getArgOperand(1),
+ ConstantInt::get(TD->getIntPtrType(*Context), // Copy the
+ FormatStr.size() + 1), 1); // nul byte.
+ return ConstantInt::get(CI->getType(), FormatStr.size());
+ }
+
+ // The remaining optimizations require the format string to be "%s" or "%c"
+ // and have an extra operand.
+ if (FormatStr.size() != 2 || FormatStr[0] != '%' ||
+ CI->getNumArgOperands() < 3)
+ return 0;
+
+ // Decode the second character of the format string.
+ if (FormatStr[1] == 'c') {
+ // sprintf(dst, "%c", chr) --> *(i8*)dst = chr; *((i8*)dst+1) = 0
+ if (!CI->getArgOperand(2)->getType()->isIntegerTy()) return 0;
+ Value *V = B.CreateTrunc(CI->getArgOperand(2), B.getInt8Ty(), "char");
+ Value *Ptr = CastToCStr(CI->getArgOperand(0), B);
+ B.CreateStore(V, Ptr);
+ Ptr = B.CreateGEP(Ptr, B.getInt32(1), "nul");
+ B.CreateStore(B.getInt8(0), Ptr);
+
+ return ConstantInt::get(CI->getType(), 1);
+ }
+
+ if (FormatStr[1] == 's') {
+ // These optimizations require DataLayout.
+ if (!TD) return 0;
+
+ // sprintf(dest, "%s", str) -> llvm.memcpy(dest, str, strlen(str)+1, 1)
+ if (!CI->getArgOperand(2)->getType()->isPointerTy()) return 0;
+
+ Value *Len = EmitStrLen(CI->getArgOperand(2), B, TD, TLI);
+ if (!Len)
+ return 0;
+ Value *IncLen = B.CreateAdd(Len,
+ ConstantInt::get(Len->getType(), 1),
+ "leninc");
+ B.CreateMemCpy(CI->getArgOperand(0), CI->getArgOperand(2), IncLen, 1);
+
+ // The sprintf result is the unincremented number of bytes in the string.
+ return B.CreateIntCast(Len, CI->getType(), false);
+ }
+ return 0;
+ }
+
+ virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+ // Require two fixed pointer arguments and an integer result.
+ FunctionType *FT = Callee->getFunctionType();
+ if (FT->getNumParams() != 2 || !FT->getParamType(0)->isPointerTy() ||
+ !FT->getParamType(1)->isPointerTy() ||
+ !FT->getReturnType()->isIntegerTy())
+ return 0;
+
+ if (Value *V = OptimizeFixedFormatString(Callee, CI, B)) {
+ return V;
+ }
+
+ // sprintf(str, format, ...) -> siprintf(str, format, ...) if no floating
+ // point arguments.
+ if (TLI->has(LibFunc::siprintf) && !callHasFloatingPointArgument(CI)) {
+ Module *M = B.GetInsertBlock()->getParent()->getParent();
+ Constant *SIPrintFFn =
+ M->getOrInsertFunction("siprintf", FT, Callee->getAttributes());
+ CallInst *New = cast<CallInst>(CI->clone());
+ New->setCalledFunction(SIPrintFFn);
+ B.Insert(New);
+ return New;
+ }
+ return 0;
+ }
+};
+
+struct FPrintFOpt : public LibCallOptimization {
+ Value *optimizeFixedFormatString(Function *Callee, CallInst *CI,
+ IRBuilder<> &B) {
+ // All the optimizations depend on the format string.
+ StringRef FormatStr;
+ if (!getConstantStringInfo(CI->getArgOperand(1), FormatStr))
+ return 0;
+
+ // fprintf(F, "foo") --> fwrite("foo", 3, 1, F)
+ if (CI->getNumArgOperands() == 2) {
+ for (unsigned i = 0, e = FormatStr.size(); i != e; ++i)
+ if (FormatStr[i] == '%') // Could handle %% -> % if we cared.
+ return 0; // We found a format specifier.
+
+ // These optimizations require DataLayout.
+ if (!TD) return 0;
+
+ Value *NewCI = EmitFWrite(CI->getArgOperand(1),
+ ConstantInt::get(TD->getIntPtrType(*Context),
+ FormatStr.size()),
+ CI->getArgOperand(0), B, TD, TLI);
+ return NewCI ? ConstantInt::get(CI->getType(), FormatStr.size()) : 0;
+ }
+
+ // The remaining optimizations require the format string to be "%s" or "%c"
+ // and have an extra operand.
+ if (FormatStr.size() != 2 || FormatStr[0] != '%' ||
+ CI->getNumArgOperands() < 3)
+ return 0;
+
+ // Decode the second character of the format string.
+ if (FormatStr[1] == 'c') {
+ // fprintf(F, "%c", chr) --> fputc(chr, F)
+ if (!CI->getArgOperand(2)->getType()->isIntegerTy()) return 0;
+ Value *NewCI = EmitFPutC(CI->getArgOperand(2), CI->getArgOperand(0), B,
+ TD, TLI);
+ return NewCI ? ConstantInt::get(CI->getType(), 1) : 0;
+ }
+
+ if (FormatStr[1] == 's') {
+ // fprintf(F, "%s", str) --> fputs(str, F)
+ if (!CI->getArgOperand(2)->getType()->isPointerTy() || !CI->use_empty())
+ return 0;
+ return EmitFPutS(CI->getArgOperand(2), CI->getArgOperand(0), B, TD, TLI);
+ }
+ return 0;
+ }
+
+ virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+ // Require two fixed paramters as pointers and integer result.
+ FunctionType *FT = Callee->getFunctionType();
+ if (FT->getNumParams() != 2 || !FT->getParamType(0)->isPointerTy() ||
+ !FT->getParamType(1)->isPointerTy() ||
+ !FT->getReturnType()->isIntegerTy())
+ return 0;
+
+ if (Value *V = optimizeFixedFormatString(Callee, CI, B)) {
+ return V;
+ }
+
+ // fprintf(stream, format, ...) -> fiprintf(stream, format, ...) if no
+ // floating point arguments.
+ if (TLI->has(LibFunc::fiprintf) && !callHasFloatingPointArgument(CI)) {
+ Module *M = B.GetInsertBlock()->getParent()->getParent();
+ Constant *FIPrintFFn =
+ M->getOrInsertFunction("fiprintf", FT, Callee->getAttributes());
+ CallInst *New = cast<CallInst>(CI->clone());
+ New->setCalledFunction(FIPrintFFn);
+ B.Insert(New);
+ return New;
+ }
+ return 0;
+ }
+};
+
+struct FWriteOpt : public LibCallOptimization {
+ virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+ // Require a pointer, an integer, an integer, a pointer, returning integer.
+ FunctionType *FT = Callee->getFunctionType();
+ if (FT->getNumParams() != 4 || !FT->getParamType(0)->isPointerTy() ||
+ !FT->getParamType(1)->isIntegerTy() ||
+ !FT->getParamType(2)->isIntegerTy() ||
+ !FT->getParamType(3)->isPointerTy() ||
+ !FT->getReturnType()->isIntegerTy())
+ return 0;
+
+ // Get the element size and count.
+ ConstantInt *SizeC = dyn_cast<ConstantInt>(CI->getArgOperand(1));
+ ConstantInt *CountC = dyn_cast<ConstantInt>(CI->getArgOperand(2));
+ if (!SizeC || !CountC) return 0;
+ uint64_t Bytes = SizeC->getZExtValue()*CountC->getZExtValue();
+
+ // If this is writing zero records, remove the call (it's a noop).
+ if (Bytes == 0)
+ return ConstantInt::get(CI->getType(), 0);
+
+ // If this is writing one byte, turn it into fputc.
+ // This optimisation is only valid, if the return value is unused.
+ if (Bytes == 1 && CI->use_empty()) { // fwrite(S,1,1,F) -> fputc(S[0],F)
+ Value *Char = B.CreateLoad(CastToCStr(CI->getArgOperand(0), B), "char");
+ Value *NewCI = EmitFPutC(Char, CI->getArgOperand(3), B, TD, TLI);
+ return NewCI ? ConstantInt::get(CI->getType(), 1) : 0;
+ }
+
+ return 0;
+ }
+};
+
+struct FPutsOpt : public LibCallOptimization {
+ virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+ // These optimizations require DataLayout.
+ if (!TD) return 0;
+
+ // Require two pointers. Also, we can't optimize if return value is used.
+ FunctionType *FT = Callee->getFunctionType();
+ if (FT->getNumParams() != 2 || !FT->getParamType(0)->isPointerTy() ||
+ !FT->getParamType(1)->isPointerTy() ||
+ !CI->use_empty())
+ return 0;
+
+ // fputs(s,F) --> fwrite(s,1,strlen(s),F)
+ uint64_t Len = GetStringLength(CI->getArgOperand(0));
+ if (!Len) return 0;
+ // Known to have no uses (see above).
+ return EmitFWrite(CI->getArgOperand(0),
+ ConstantInt::get(TD->getIntPtrType(*Context), Len-1),
+ CI->getArgOperand(1), B, TD, TLI);
+ }
+};
+
+struct PutsOpt : public LibCallOptimization {
+ virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+ // Require one fixed pointer argument and an integer/void result.
+ FunctionType *FT = Callee->getFunctionType();
+ if (FT->getNumParams() < 1 || !FT->getParamType(0)->isPointerTy() ||
+ !(FT->getReturnType()->isIntegerTy() ||
+ FT->getReturnType()->isVoidTy()))
+ return 0;
+
+ // Check for a constant string.
+ StringRef Str;
+ if (!getConstantStringInfo(CI->getArgOperand(0), Str))
+ return 0;
+
+ if (Str.empty() && CI->use_empty()) {
+ // puts("") -> putchar('\n')
+ Value *Res = EmitPutChar(B.getInt32('\n'), B, TD, TLI);
+ if (CI->use_empty() || !Res) return Res;
+ return B.CreateIntCast(Res, CI->getType(), true);
+ }
+
+ return 0;
+ }
+};
+
+} // End anonymous namespace.
+
+namespace llvm {
+
+class LibCallSimplifierImpl {
+ const DataLayout *TD;
+ const TargetLibraryInfo *TLI;
+ const LibCallSimplifier *LCS;
+ bool UnsafeFPShrink;
+ StringMap<LibCallOptimization*, BumpPtrAllocator> Optimizations;
+
+ // Fortified library call optimizations.
+ MemCpyChkOpt MemCpyChk;
+ MemMoveChkOpt MemMoveChk;
+ MemSetChkOpt MemSetChk;
+ StrCpyChkOpt StrCpyChk;
+ StpCpyChkOpt StpCpyChk;
+ StrNCpyChkOpt StrNCpyChk;
+
+ // String library call optimizations.
+ StrCatOpt StrCat;
+ StrNCatOpt StrNCat;
+ StrChrOpt StrChr;
+ StrRChrOpt StrRChr;
+ StrCmpOpt StrCmp;
+ StrNCmpOpt StrNCmp;
+ StrCpyOpt StrCpy;
+ StpCpyOpt StpCpy;
+ StrNCpyOpt StrNCpy;
+ StrLenOpt StrLen;
+ StrPBrkOpt StrPBrk;
+ StrToOpt StrTo;
+ StrSpnOpt StrSpn;
+ StrCSpnOpt StrCSpn;
+ StrStrOpt StrStr;
+
+ // Memory library call optimizations.
+ MemCmpOpt MemCmp;
+ MemCpyOpt MemCpy;
+ MemMoveOpt MemMove;
+ MemSetOpt MemSet;
+
+ // Math library call optimizations.
+ UnaryDoubleFPOpt UnaryDoubleFP, UnsafeUnaryDoubleFP;
+ CosOpt Cos; PowOpt Pow; Exp2Opt Exp2;
+
+ // Integer library call optimizations.
+ FFSOpt FFS;
+ AbsOpt Abs;
+ IsDigitOpt IsDigit;
+ IsAsciiOpt IsAscii;
+ ToAsciiOpt ToAscii;
+
+ // Formatting and IO library call optimizations.
+ PrintFOpt PrintF;
+ SPrintFOpt SPrintF;
+ FPrintFOpt FPrintF;
+ FWriteOpt FWrite;
+ FPutsOpt FPuts;
+ PutsOpt Puts;
+
+ void initOptimizations();
+ void addOpt(LibFunc::Func F, LibCallOptimization* Opt);
+ void addOpt(LibFunc::Func F1, LibFunc::Func F2, LibCallOptimization* Opt);
+public:
+ LibCallSimplifierImpl(const DataLayout *TD, const TargetLibraryInfo *TLI,
+ const LibCallSimplifier *LCS,
+ bool UnsafeFPShrink = false)
+ : UnaryDoubleFP(false), UnsafeUnaryDoubleFP(true),
+ Cos(UnsafeFPShrink), Pow(UnsafeFPShrink), Exp2(UnsafeFPShrink) {
+ this->TD = TD;
+ this->TLI = TLI;
+ this->LCS = LCS;
+ this->UnsafeFPShrink = UnsafeFPShrink;
+ }
+
+ Value *optimizeCall(CallInst *CI);
+};
+
+void LibCallSimplifierImpl::initOptimizations() {
+ // Fortified library call optimizations.
+ Optimizations["__memcpy_chk"] = &MemCpyChk;
+ Optimizations["__memmove_chk"] = &MemMoveChk;
+ Optimizations["__memset_chk"] = &MemSetChk;
+ Optimizations["__strcpy_chk"] = &StrCpyChk;
+ Optimizations["__stpcpy_chk"] = &StpCpyChk;
+ Optimizations["__strncpy_chk"] = &StrNCpyChk;
+ Optimizations["__stpncpy_chk"] = &StrNCpyChk;
+
+ // String library call optimizations.
+ addOpt(LibFunc::strcat, &StrCat);
+ addOpt(LibFunc::strncat, &StrNCat);
+ addOpt(LibFunc::strchr, &StrChr);
+ addOpt(LibFunc::strrchr, &StrRChr);
+ addOpt(LibFunc::strcmp, &StrCmp);
+ addOpt(LibFunc::strncmp, &StrNCmp);
+ addOpt(LibFunc::strcpy, &StrCpy);
+ addOpt(LibFunc::stpcpy, &StpCpy);
+ addOpt(LibFunc::strncpy, &StrNCpy);
+ addOpt(LibFunc::strlen, &StrLen);
+ addOpt(LibFunc::strpbrk, &StrPBrk);
+ addOpt(LibFunc::strtol, &StrTo);
+ addOpt(LibFunc::strtod, &StrTo);
+ addOpt(LibFunc::strtof, &StrTo);
+ addOpt(LibFunc::strtoul, &StrTo);
+ addOpt(LibFunc::strtoll, &StrTo);
+ addOpt(LibFunc::strtold, &StrTo);
+ addOpt(LibFunc::strtoull, &StrTo);
+ addOpt(LibFunc::strspn, &StrSpn);
+ addOpt(LibFunc::strcspn, &StrCSpn);
+ addOpt(LibFunc::strstr, &StrStr);
+
+ // Memory library call optimizations.
+ addOpt(LibFunc::memcmp, &MemCmp);
+ addOpt(LibFunc::memcpy, &MemCpy);
+ addOpt(LibFunc::memmove, &MemMove);
+ addOpt(LibFunc::memset, &MemSet);
+
+ // Math library call optimizations.
+ addOpt(LibFunc::ceil, LibFunc::ceilf, &UnaryDoubleFP);
+ addOpt(LibFunc::fabs, LibFunc::fabsf, &UnaryDoubleFP);
+ addOpt(LibFunc::floor, LibFunc::floorf, &UnaryDoubleFP);
+ addOpt(LibFunc::rint, LibFunc::rintf, &UnaryDoubleFP);
+ addOpt(LibFunc::round, LibFunc::roundf, &UnaryDoubleFP);
+ addOpt(LibFunc::nearbyint, LibFunc::nearbyintf, &UnaryDoubleFP);
+ addOpt(LibFunc::trunc, LibFunc::truncf, &UnaryDoubleFP);
+
+ if(UnsafeFPShrink) {
+ addOpt(LibFunc::acos, LibFunc::acosf, &UnsafeUnaryDoubleFP);
+ addOpt(LibFunc::acosh, LibFunc::acoshf, &UnsafeUnaryDoubleFP);
+ addOpt(LibFunc::asin, LibFunc::asinf, &UnsafeUnaryDoubleFP);
+ addOpt(LibFunc::asinh, LibFunc::asinhf, &UnsafeUnaryDoubleFP);
+ addOpt(LibFunc::atan, LibFunc::atanf, &UnsafeUnaryDoubleFP);
+ addOpt(LibFunc::atanh, LibFunc::atanhf, &UnsafeUnaryDoubleFP);
+ addOpt(LibFunc::cbrt, LibFunc::cbrtf, &UnsafeUnaryDoubleFP);
+ addOpt(LibFunc::cosh, LibFunc::coshf, &UnsafeUnaryDoubleFP);
+ addOpt(LibFunc::exp, LibFunc::expf, &UnsafeUnaryDoubleFP);
+ addOpt(LibFunc::exp10, LibFunc::exp10f, &UnsafeUnaryDoubleFP);
+ addOpt(LibFunc::expm1, LibFunc::expm1f, &UnsafeUnaryDoubleFP);
+ addOpt(LibFunc::log, LibFunc::logf, &UnsafeUnaryDoubleFP);
+ addOpt(LibFunc::log10, LibFunc::log10f, &UnsafeUnaryDoubleFP);
+ addOpt(LibFunc::log1p, LibFunc::log1pf, &UnsafeUnaryDoubleFP);
+ addOpt(LibFunc::log2, LibFunc::log2f, &UnsafeUnaryDoubleFP);
+ addOpt(LibFunc::logb, LibFunc::logbf, &UnsafeUnaryDoubleFP);
+ addOpt(LibFunc::sin, LibFunc::sinf, &UnsafeUnaryDoubleFP);
+ addOpt(LibFunc::sinh, LibFunc::sinhf, &UnsafeUnaryDoubleFP);
+ addOpt(LibFunc::sqrt, LibFunc::sqrtf, &UnsafeUnaryDoubleFP);
+ addOpt(LibFunc::tan, LibFunc::tanf, &UnsafeUnaryDoubleFP);
+ addOpt(LibFunc::tanh, LibFunc::tanhf, &UnsafeUnaryDoubleFP);
+ }
+
+ addOpt(LibFunc::cosf, &Cos);
+ addOpt(LibFunc::cos, &Cos);
+ addOpt(LibFunc::cosl, &Cos);
+ addOpt(LibFunc::powf, &Pow);
+ addOpt(LibFunc::pow, &Pow);
+ addOpt(LibFunc::powl, &Pow);
+ Optimizations["llvm.pow.f32"] = &Pow;
+ Optimizations["llvm.pow.f64"] = &Pow;
+ Optimizations["llvm.pow.f80"] = &Pow;
+ Optimizations["llvm.pow.f128"] = &Pow;
+ Optimizations["llvm.pow.ppcf128"] = &Pow;
+ addOpt(LibFunc::exp2l, &Exp2);
+ addOpt(LibFunc::exp2, &Exp2);
+ addOpt(LibFunc::exp2f, &Exp2);
+ Optimizations["llvm.exp2.ppcf128"] = &Exp2;
+ Optimizations["llvm.exp2.f128"] = &Exp2;
+ Optimizations["llvm.exp2.f80"] = &Exp2;
+ Optimizations["llvm.exp2.f64"] = &Exp2;
+ Optimizations["llvm.exp2.f32"] = &Exp2;
+
+ // Integer library call optimizations.
+ addOpt(LibFunc::ffs, &FFS);
+ addOpt(LibFunc::ffsl, &FFS);
+ addOpt(LibFunc::ffsll, &FFS);
+ addOpt(LibFunc::abs, &Abs);
+ addOpt(LibFunc::labs, &Abs);
+ addOpt(LibFunc::llabs, &Abs);
+ addOpt(LibFunc::isdigit, &IsDigit);
+ addOpt(LibFunc::isascii, &IsAscii);
+ addOpt(LibFunc::toascii, &ToAscii);
+
+ // Formatting and IO library call optimizations.
+ addOpt(LibFunc::printf, &PrintF);
+ addOpt(LibFunc::sprintf, &SPrintF);
+ addOpt(LibFunc::fprintf, &FPrintF);
+ addOpt(LibFunc::fwrite, &FWrite);
+ addOpt(LibFunc::fputs, &FPuts);
+ addOpt(LibFunc::puts, &Puts);
+}
+
+Value *LibCallSimplifierImpl::optimizeCall(CallInst *CI) {
+ if (Optimizations.empty())
+ initOptimizations();
+
+ Function *Callee = CI->getCalledFunction();
+ LibCallOptimization *LCO = Optimizations.lookup(Callee->getName());
+ if (LCO) {
+ IRBuilder<> Builder(CI);
+ return LCO->optimizeCall(CI, TD, TLI, LCS, Builder);
+ }
+ return 0;
+}
+
+void LibCallSimplifierImpl::addOpt(LibFunc::Func F, LibCallOptimization* Opt) {
+ if (TLI->has(F))
+ Optimizations[TLI->getName(F)] = Opt;
+}
+
+void LibCallSimplifierImpl::addOpt(LibFunc::Func F1, LibFunc::Func F2,
+ LibCallOptimization* Opt) {
+ if (TLI->has(F1) && TLI->has(F2))
+ Optimizations[TLI->getName(F1)] = Opt;
+}
+
+LibCallSimplifier::LibCallSimplifier(const DataLayout *TD,
+ const TargetLibraryInfo *TLI,
+ bool UnsafeFPShrink) {
+ Impl = new LibCallSimplifierImpl(TD, TLI, this, UnsafeFPShrink);
+}
+
+LibCallSimplifier::~LibCallSimplifier() {
+ delete Impl;
+}
+
+Value *LibCallSimplifier::optimizeCall(CallInst *CI) {
+ if (CI->hasFnAttr(Attribute::NoBuiltin)) return 0;
+ return Impl->optimizeCall(CI);
+}
+
+void LibCallSimplifier::replaceAllUsesWith(Instruction *I, Value *With) const {
+ I->replaceAllUsesWith(With);
+ I->eraseFromParent();
}
}
projects / oota-llvm.git / blobdiff