SimplifyLibCalls.cpp [plain text]
#define DEBUG_TYPE "simplify-libcalls"
#include "llvm/Transforms/Scalar.h"
#include "llvm/Transforms/Utils/BuildLibCalls.h"
#include "llvm/IRBuilder.h"
#include "llvm/Intrinsics.h"
#include "llvm/LLVMContext.h"
#include "llvm/Module.h"
#include "llvm/Pass.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/ADT/StringMap.h"
#include "llvm/Analysis/ValueTracking.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Target/TargetData.h"
#include "llvm/Target/TargetLibraryInfo.h"
#include "llvm/Config/config.h" // FIXME: Shouldn't depend on host!
using namespace llvm;
STATISTIC(NumSimplified, "Number of library calls simplified");
STATISTIC(NumAnnotated, "Number of attributes added to library functions");
static cl::opt<bool> UnsafeFPShrink("enable-double-float-shrink", cl::Hidden,
cl::init(false),
cl::desc("Enable unsafe double to float "
"shrinking for math lib calls"));
namespace {
class LibCallOptimization {
protected:
Function *Caller;
const TargetData *TD;
const TargetLibraryInfo *TLI;
LLVMContext* Context;
public:
LibCallOptimization() { }
virtual ~LibCallOptimization() {}
virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B)
=0;
Value *OptimizeCall(CallInst *CI, const TargetData *TD,
const TargetLibraryInfo *TLI, IRBuilder<> &B) {
Caller = CI->getParent()->getParent();
this->TD = TD;
this->TLI = TLI;
if (CI->getCalledFunction())
Context = &CI->getCalledFunction()->getContext();
if (CI->getCallingConv() != llvm::CallingConv::C)
return NULL;
return CallOptimizer(CI->getCalledFunction(), CI, B);
}
};
}
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;
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;
}
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;
return false;
}
return true;
}
namespace {
struct StrCatOpt : public LibCallOptimization {
virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
FunctionType *FT = Callee->getFunctionType();
if (FT->getNumParams() != 2 ||
FT->getReturnType() != B.getInt8PtrTy() ||
FT->getParamType(0) != FT->getReturnType() ||
FT->getParamType(1) != FT->getReturnType())
return 0;
Value *Dst = CI->getArgOperand(0);
Value *Src = CI->getArgOperand(1);
uint64_t Len = GetStringLength(Src);
if (Len == 0) return 0;
--Len;
if (Len == 0)
return Dst;
if (!TD) return 0;
return EmitStrLenMemCpy(Src, Dst, Len, B);
}
Value *EmitStrLenMemCpy(Value *Src, Value *Dst, uint64_t Len, IRBuilder<> &B) {
Value *DstLen = EmitStrLen(Dst, B, TD, TLI);
if (!DstLen)
return 0;
Value *CpyDst = B.CreateGEP(Dst, DstLen, "endptr");
B.CreateMemCpy(CpyDst, Src,
ConstantInt::get(TD->getIntPtrType(*Context), Len + 1), 1);
return Dst;
}
};
struct StrNCatOpt : public StrCatOpt {
virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
FunctionType *FT = Callee->getFunctionType();
if (FT->getNumParams() != 3 ||
FT->getReturnType() != B.getInt8PtrTy() ||
FT->getParamType(0) != FT->getReturnType() ||
FT->getParamType(1) != FT->getReturnType() ||
!FT->getParamType(2)->isIntegerTy())
return 0;
Value *Dst = CI->getArgOperand(0);
Value *Src = CI->getArgOperand(1);
uint64_t Len;
if (ConstantInt *LengthArg = dyn_cast<ConstantInt>(CI->getArgOperand(2)))
Len = LengthArg->getZExtValue();
else
return 0;
uint64_t SrcLen = GetStringLength(Src);
if (SrcLen == 0) return 0;
--SrcLen;
if (SrcLen == 0 || Len == 0) return Dst;
if (!TD) return 0;
if (Len < SrcLen) return 0;
return EmitStrLenMemCpy(Src, Dst, SrcLen, B);
}
};
struct StrChrOpt : public LibCallOptimization {
virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
FunctionType *FT = Callee->getFunctionType();
if (FT->getNumParams() != 2 ||
FT->getReturnType() != B.getInt8PtrTy() ||
FT->getParamType(0) != FT->getReturnType() ||
!FT->getParamType(1)->isIntegerTy(32))
return 0;
Value *SrcStr = CI->getArgOperand(0);
ConstantInt *CharC = dyn_cast<ConstantInt>(CI->getArgOperand(1));
if (CharC == 0) {
if (!TD) return 0;
uint64_t Len = GetStringLength(SrcStr);
if (Len == 0 || !FT->getParamType(1)->isIntegerTy(32)) return 0;
return EmitMemChr(SrcStr, CI->getArgOperand(1), ConstantInt::get(TD->getIntPtrType(*Context), Len),
B, TD, TLI);
}
StringRef Str;
if (!getConstantStringInfo(SrcStr, Str))
return 0;
size_t I = CharC->getSExtValue() == 0 ?
Str.size() : Str.find(CharC->getSExtValue());
if (I == StringRef::npos) return Constant::getNullValue(CI->getType());
return B.CreateGEP(SrcStr, B.getInt64(I), "strchr");
}
};
struct StrRChrOpt : public LibCallOptimization {
virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
FunctionType *FT = Callee->getFunctionType();
if (FT->getNumParams() != 2 ||
FT->getReturnType() != B.getInt8PtrTy() ||
FT->getParamType(0) != FT->getReturnType() ||
!FT->getParamType(1)->isIntegerTy(32))
return 0;
Value *SrcStr = CI->getArgOperand(0);
ConstantInt *CharC = dyn_cast<ConstantInt>(CI->getArgOperand(1));
if (!CharC)
return 0;
StringRef Str;
if (!getConstantStringInfo(SrcStr, Str)) {
if (TD && CharC->isZero())
return EmitStrChr(SrcStr, '\0', B, TD, TLI);
return 0;
}
size_t I = CharC->getSExtValue() == 0 ?
Str.size() : Str.rfind(CharC->getSExtValue());
if (I == StringRef::npos) return Constant::getNullValue(CI->getType());
return B.CreateGEP(SrcStr, B.getInt64(I), "strrchr");
}
};
struct StrCmpOpt : public LibCallOptimization {
virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
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;
Value *Str1P = CI->getArgOperand(0), *Str2P = CI->getArgOperand(1);
if (Str1P == Str2P) return ConstantInt::get(CI->getType(), 0);
StringRef Str1, Str2;
bool HasStr1 = getConstantStringInfo(Str1P, Str1);
bool HasStr2 = getConstantStringInfo(Str2P, Str2);
if (HasStr1 && HasStr2)
return ConstantInt::get(CI->getType(), Str1.compare(Str2));
if (HasStr1 && Str1.empty()) return B.CreateNeg(B.CreateZExt(B.CreateLoad(Str2P, "strcmpload"),
CI->getType()));
if (HasStr2 && Str2.empty()) return B.CreateZExt(B.CreateLoad(Str1P, "strcmpload"), CI->getType());
uint64_t Len1 = GetStringLength(Str1P);
uint64_t Len2 = GetStringLength(Str2P);
if (Len1 && Len2) {
if (!TD) return 0;
return EmitMemCmp(Str1P, Str2P,
ConstantInt::get(TD->getIntPtrType(*Context),
std::min(Len1, Len2)), B, TD, TLI);
}
return 0;
}
};
struct StrNCmpOpt : public LibCallOptimization {
virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
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) return ConstantInt::get(CI->getType(), 0);
uint64_t Length;
if (ConstantInt *LengthArg = dyn_cast<ConstantInt>(CI->getArgOperand(2)))
Length = LengthArg->getZExtValue();
else
return 0;
if (Length == 0) return ConstantInt::get(CI->getType(), 0);
if (TD && Length == 1) return EmitMemCmp(Str1P, Str2P, CI->getArgOperand(2), B, TD, TLI);
StringRef Str1, Str2;
bool HasStr1 = getConstantStringInfo(Str1P, Str1);
bool HasStr2 = getConstantStringInfo(Str2P, Str2);
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()) return B.CreateNeg(B.CreateZExt(B.CreateLoad(Str2P, "strcmpload"),
CI->getType()));
if (HasStr2 && Str2.empty()) return B.CreateZExt(B.CreateLoad(Str1P, "strcmpload"), CI->getType());
return 0;
}
};
struct StrCpyOpt : public LibCallOptimization {
bool OptChkCall;
StrCpyOpt(bool c) : OptChkCall(c) {}
virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
unsigned NumParams = OptChkCall ? 3 : 2;
FunctionType *FT = Callee->getFunctionType();
if (FT->getNumParams() != NumParams ||
FT->getReturnType() != FT->getParamType(0) ||
FT->getParamType(0) != FT->getParamType(1) ||
FT->getParamType(0) != B.getInt8PtrTy())
return 0;
Value *Dst = CI->getArgOperand(0), *Src = CI->getArgOperand(1);
if (Dst == Src) return Src;
if (!TD) return 0;
uint64_t Len = GetStringLength(Src);
if (Len == 0) return 0;
if (!OptChkCall ||
!EmitMemCpyChk(Dst, Src,
ConstantInt::get(TD->getIntPtrType(*Context), Len),
CI->getArgOperand(2), B, TD, TLI))
B.CreateMemCpy(Dst, Src,
ConstantInt::get(TD->getIntPtrType(*Context), Len), 1);
return Dst;
}
};
struct StpCpyOpt: public LibCallOptimization {
bool OptChkCall;
StpCpyOpt(bool c) : OptChkCall(c) {}
virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
unsigned NumParams = OptChkCall ? 3 : 2;
FunctionType *FT = Callee->getFunctionType();
if (FT->getNumParams() != NumParams ||
FT->getReturnType() != FT->getParamType(0) ||
FT->getParamType(0) != FT->getParamType(1) ||
FT->getParamType(0) != B.getInt8PtrTy())
return 0;
if (!TD) return 0;
Value *Dst = CI->getArgOperand(0), *Src = CI->getArgOperand(1);
if (Dst == Src) { Value *StrLen = EmitStrLen(Src, B, TD, TLI);
return StrLen ? B.CreateInBoundsGEP(Dst, StrLen) : 0;
}
uint64_t Len = GetStringLength(Src);
if (Len == 0) return 0;
Value *LenV = ConstantInt::get(TD->getIntPtrType(*Context), Len);
Value *DstEnd = B.CreateGEP(Dst,
ConstantInt::get(TD->getIntPtrType(*Context),
Len - 1));
if (!OptChkCall || !EmitMemCpyChk(Dst, Src, LenV, CI->getArgOperand(2), B,
TD, TLI))
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);
uint64_t SrcLen = GetStringLength(Src);
if (SrcLen == 0) return 0;
--SrcLen;
if (SrcLen == 0) {
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;
if (!TD) return 0;
if (Len > SrcLen+1) return 0;
B.CreateMemCpy(Dst, Src,
ConstantInt::get(TD->getIntPtrType(*Context), Len), 1);
return Dst;
}
};
struct StrLenOpt : public LibCallOptimization {
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);
if (uint64_t Len = GetStringLength(Src))
return ConstantInt::get(CI->getType(), Len-1);
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);
if ((HasS1 && S1.empty()) || (HasS2 && S2.empty()))
return Constant::getNullValue(CI->getType());
if (HasS1 && HasS2) {
size_t I = S1.find_first_of(S2);
if (I == std::string::npos) return Constant::getNullValue(CI->getType());
return B.CreateGEP(CI->getArgOperand(0), B.getInt64(I), "strpbrk");
}
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)) {
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);
if ((HasS1 && S1.empty()) || (HasS2 && S2.empty()))
return Constant::getNullValue(CI->getType());
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);
if (HasS1 && S1.empty())
return Constant::getNullValue(CI->getType());
if (HasS1 && HasS2) {
size_t Pos = S1.find_first_of(S2);
if (Pos == StringRef::npos) Pos = S1.size();
return ConstantInt::get(CI->getType(), Pos);
}
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;
if (CI->getArgOperand(0) == CI->getArgOperand(1))
return B.CreateBitCast(CI->getArgOperand(0), CI->getType());
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;
}
StringRef SearchStr, ToFindStr;
bool HasStr1 = getConstantStringInfo(CI->getArgOperand(0), SearchStr);
bool HasStr2 = getConstantStringInfo(CI->getArgOperand(1), ToFindStr);
if (HasStr2 && ToFindStr.empty())
return B.CreateBitCast(CI->getArgOperand(0), CI->getType());
if (HasStr1 && HasStr2) {
std::string::size_type Offset = SearchStr.find(ToFindStr);
if (Offset == StringRef::npos) return Constant::getNullValue(CI->getType());
Value *Result = CastToCStr(CI->getArgOperand(0), B);
Result = B.CreateConstInBoundsGEP1_64(Result, Offset, "strstr");
return B.CreateBitCast(Result, CI->getType());
}
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) return Constant::getNullValue(CI->getType());
ConstantInt *LenC = dyn_cast<ConstantInt>(CI->getArgOperand(2));
if (!LenC) return 0;
uint64_t Len = LenC->getZExtValue();
if (Len == 0) return Constant::getNullValue(CI->getType());
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");
}
StringRef LHSStr, RHSStr;
if (getConstantStringInfo(LHS, LHSStr) &&
getConstantStringInfo(RHS, RHSStr)) {
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;
}
};
struct MemCpyOpt : public LibCallOptimization {
virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
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;
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) {
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;
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) {
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;
Value *Val = B.CreateIntCast(CI->getArgOperand(1), B.getInt8Ty(), false);
B.CreateMemSet(CI->getArgOperand(0), Val, CI->getArgOperand(2), 1);
return CI->getArgOperand(0);
}
};
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) {
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;
}
}
FPExtInst *Cast = dyn_cast<FPExtInst>(CI->getArgOperand(0));
if (Cast == 0 || !Cast->getOperand(0)->getType()->isFloatTy())
return 0;
Value *V = Cast->getOperand(0);
V = EmitUnaryFloatFnCall(V, Callee->getName(), B, Callee->getAttributes());
return B.CreateFPExt(V, B.getDoubleTy());
}
};
struct CosOpt : public LibCallOptimization {
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();
if (FT->getNumParams() != 1 || FT->getReturnType() != FT->getParamType(0) ||
!FT->getParamType(0)->isFloatingPointTy())
return Ret;
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 LibCallOptimization {
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();
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)) return Op1C;
if (Op1C->isExactlyValue(2.0)) return EmitUnaryFloatFnCall(Op2, "exp2", B, Callee->getAttributes());
}
ConstantFP *Op2C = dyn_cast<ConstantFP>(Op2);
if (Op2C == 0) return Ret;
if (Op2C->getValueAPF().isZero()) return ConstantFP::get(CI->getType(), 1.0);
if (Op2C->isExactlyValue(0.5)) {
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)) return Op1;
if (Op2C->isExactlyValue(2.0)) return B.CreateFMul(Op1, Op1, "pow2");
if (Op2C->isExactlyValue(-1.0)) return B.CreateFDiv(ConstantFP::get(CI->getType(), 1.0),
Op1, "powrecip");
return 0;
}
};
struct Exp2Opt : public LibCallOptimization {
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();
if (FT->getNumParams() != 1 || FT->getReturnType() != FT->getParamType(0) ||
!FT->getParamType(0)->isFloatingPointTy())
return Ret;
Value *Op = CI->getArgOperand(0);
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;
}
};
struct FFSOpt : public LibCallOptimization {
virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
FunctionType *FT = Callee->getFunctionType();
if (FT->getNumParams() != 1 ||
!FT->getReturnType()->isIntegerTy(32) ||
!FT->getParamType(0)->isIntegerTy())
return 0;
Value *Op = CI->getArgOperand(0);
if (ConstantInt *CI = dyn_cast<ConstantInt>(Op)) {
if (CI->isZero()) return B.getInt32(0);
return B.getInt32(CI->getValue().countTrailingZeros() + 1);
}
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 IsDigitOpt : public LibCallOptimization {
virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
FunctionType *FT = Callee->getFunctionType();
if (FT->getNumParams() != 1 || !FT->getReturnType()->isIntegerTy() ||
!FT->getParamType(0)->isIntegerTy(32))
return 0;
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();
if (FT->getNumParams() != 1 || !FT->getReturnType()->isIntegerTy() ||
!FT->getParamType(0)->isIntegerTy(32))
return 0;
Value *Op = CI->getArgOperand(0);
Op = B.CreateICmpULT(Op, B.getInt32(128), "isascii");
return B.CreateZExt(Op, CI->getType());
}
};
struct AbsOpt : public LibCallOptimization {
virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
FunctionType *FT = Callee->getFunctionType();
if (FT->getNumParams() != 1 || !FT->getReturnType()->isIntegerTy() ||
FT->getParamType(0) != FT->getReturnType())
return 0;
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 ToAsciiOpt : public LibCallOptimization {
virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
FunctionType *FT = Callee->getFunctionType();
if (FT->getNumParams() != 1 || FT->getReturnType() != FT->getParamType(0) ||
!FT->getParamType(0)->isIntegerTy(32))
return 0;
return B.CreateAnd(CI->getArgOperand(0),
ConstantInt::get(CI->getType(),0x7F));
}
};
struct PrintFOpt : public LibCallOptimization {
Value *OptimizeFixedFormatString(Function *Callee, CallInst *CI,
IRBuilder<> &B) {
StringRef FormatStr;
if (!getConstantStringInfo(CI->getArgOperand(0), FormatStr))
return 0;
if (FormatStr.empty()) return CI->use_empty() ? (Value*)CI :
ConstantInt::get(CI->getType(), 0);
if (!CI->use_empty())
return 0;
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);
}
if (FormatStr[FormatStr.size()-1] == '\n' &&
FormatStr.find('%') == std::string::npos) { 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);
}
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);
}
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) {
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;
}
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) {
StringRef FormatStr;
if (!getConstantStringInfo(CI->getArgOperand(1), FormatStr))
return 0;
if (CI->getNumArgOperands() == 2) {
for (unsigned i = 0, e = FormatStr.size(); i != e; ++i)
if (FormatStr[i] == '%')
return 0;
if (!TD) return 0;
B.CreateMemCpy(CI->getArgOperand(0), CI->getArgOperand(1),
ConstantInt::get(TD->getIntPtrType(*Context), FormatStr.size() + 1), 1); return ConstantInt::get(CI->getType(), FormatStr.size());
}
if (FormatStr.size() != 2 || FormatStr[0] != '%' ||
CI->getNumArgOperands() < 3)
return 0;
if (FormatStr[1] == 'c') {
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') {
if (!TD) return 0;
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);
return B.CreateIntCast(Len, CI->getType(), false);
}
return 0;
}
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()->isIntegerTy())
return 0;
if (Value *V = OptimizeFixedFormatString(Callee, CI, B)) {
return V;
}
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 FWriteOpt : public LibCallOptimization {
virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
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;
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 (Bytes == 0)
return ConstantInt::get(CI->getType(), 0);
if (Bytes == 1 && CI->use_empty()) { 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) {
if (!TD) return 0;
FunctionType *FT = Callee->getFunctionType();
if (FT->getNumParams() != 2 || !FT->getParamType(0)->isPointerTy() ||
!FT->getParamType(1)->isPointerTy() ||
!CI->use_empty())
return 0;
uint64_t Len = GetStringLength(CI->getArgOperand(0));
if (!Len) return 0;
return EmitFWrite(CI->getArgOperand(0),
ConstantInt::get(TD->getIntPtrType(*Context), Len-1),
CI->getArgOperand(1), B, TD, TLI);
}
};
struct FPrintFOpt : public LibCallOptimization {
Value *OptimizeFixedFormatString(Function *Callee, CallInst *CI,
IRBuilder<> &B) {
StringRef FormatStr;
if (!getConstantStringInfo(CI->getArgOperand(1), FormatStr))
return 0;
if (CI->getNumArgOperands() == 2) {
for (unsigned i = 0, e = FormatStr.size(); i != e; ++i)
if (FormatStr[i] == '%') return 0;
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;
}
if (FormatStr.size() != 2 || FormatStr[0] != '%' ||
CI->getNumArgOperands() < 3)
return 0;
if (FormatStr[1] == 'c') {
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') {
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) {
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;
}
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 PutsOpt : public LibCallOptimization {
virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
FunctionType *FT = Callee->getFunctionType();
if (FT->getNumParams() < 1 || !FT->getParamType(0)->isPointerTy() ||
!(FT->getReturnType()->isIntegerTy() ||
FT->getReturnType()->isVoidTy()))
return 0;
StringRef Str;
if (!getConstantStringInfo(CI->getArgOperand(0), Str))
return 0;
if (Str.empty() && CI->use_empty()) {
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;
}
};
}
namespace {
class SimplifyLibCalls : public FunctionPass {
TargetLibraryInfo *TLI;
StringMap<LibCallOptimization*> Optimizations;
StrCatOpt StrCat; StrNCatOpt StrNCat; StrChrOpt StrChr; StrRChrOpt StrRChr;
StrCmpOpt StrCmp; StrNCmpOpt StrNCmp;
StrCpyOpt StrCpy; StrCpyOpt StrCpyChk;
StpCpyOpt StpCpy; StpCpyOpt StpCpyChk;
StrNCpyOpt StrNCpy;
StrLenOpt StrLen; StrPBrkOpt StrPBrk;
StrToOpt StrTo; StrSpnOpt StrSpn; StrCSpnOpt StrCSpn; StrStrOpt StrStr;
MemCmpOpt MemCmp; MemCpyOpt MemCpy; MemMoveOpt MemMove; MemSetOpt MemSet;
CosOpt Cos; PowOpt Pow; Exp2Opt Exp2;
UnaryDoubleFPOpt UnaryDoubleFP, UnsafeUnaryDoubleFP;
FFSOpt FFS; AbsOpt Abs; IsDigitOpt IsDigit; IsAsciiOpt IsAscii;
ToAsciiOpt ToAscii;
SPrintFOpt SPrintF; PrintFOpt PrintF;
FWriteOpt FWrite; FPutsOpt FPuts; FPrintFOpt FPrintF;
PutsOpt Puts;
bool Modified; public:
static char ID; SimplifyLibCalls() : FunctionPass(ID), StrCpy(false), StrCpyChk(true),
StpCpy(false), StpCpyChk(true),
UnaryDoubleFP(false), UnsafeUnaryDoubleFP(true) {
initializeSimplifyLibCallsPass(*PassRegistry::getPassRegistry());
}
void AddOpt(LibFunc::Func F, LibCallOptimization* Opt);
void AddOpt(LibFunc::Func F1, LibFunc::Func F2, LibCallOptimization* Opt);
void InitOptimizations();
bool runOnFunction(Function &F);
void setDoesNotAccessMemory(Function &F);
void setOnlyReadsMemory(Function &F);
void setDoesNotThrow(Function &F);
void setDoesNotCapture(Function &F, unsigned n);
void setDoesNotAlias(Function &F, unsigned n);
bool doInitialization(Module &M);
void inferPrototypeAttributes(Function &F);
virtual void getAnalysisUsage(AnalysisUsage &AU) const {
AU.addRequired<TargetLibraryInfo>();
}
};
}
char SimplifyLibCalls::ID = 0;
INITIALIZE_PASS_BEGIN(SimplifyLibCalls, "simplify-libcalls",
"Simplify well-known library calls", false, false)
INITIALIZE_PASS_DEPENDENCY(TargetLibraryInfo)
INITIALIZE_PASS_END(SimplifyLibCalls, "simplify-libcalls",
"Simplify well-known library calls", false, false)
FunctionPass *llvm::createSimplifyLibCallsPass() {
return new SimplifyLibCalls();
}
void SimplifyLibCalls::AddOpt(LibFunc::Func F, LibCallOptimization* Opt) {
if (TLI->has(F))
Optimizations[TLI->getName(F)] = Opt;
}
void SimplifyLibCalls::AddOpt(LibFunc::Func F1, LibFunc::Func F2,
LibCallOptimization* Opt) {
if (TLI->has(F1) && TLI->has(F2))
Optimizations[TLI->getName(F1)] = Opt;
}
void SimplifyLibCalls::InitOptimizations() {
Optimizations["strcat"] = &StrCat;
Optimizations["strncat"] = &StrNCat;
Optimizations["strchr"] = &StrChr;
Optimizations["strrchr"] = &StrRChr;
Optimizations["strcmp"] = &StrCmp;
Optimizations["strncmp"] = &StrNCmp;
Optimizations["strcpy"] = &StrCpy;
Optimizations["strncpy"] = &StrNCpy;
Optimizations["stpcpy"] = &StpCpy;
Optimizations["strlen"] = &StrLen;
Optimizations["strpbrk"] = &StrPBrk;
Optimizations["strtol"] = &StrTo;
Optimizations["strtod"] = &StrTo;
Optimizations["strtof"] = &StrTo;
Optimizations["strtoul"] = &StrTo;
Optimizations["strtoll"] = &StrTo;
Optimizations["strtold"] = &StrTo;
Optimizations["strtoull"] = &StrTo;
Optimizations["strspn"] = &StrSpn;
Optimizations["strcspn"] = &StrCSpn;
Optimizations["strstr"] = &StrStr;
Optimizations["memcmp"] = &MemCmp;
AddOpt(LibFunc::memcpy, &MemCpy);
Optimizations["memmove"] = &MemMove;
AddOpt(LibFunc::memset, &MemSet);
Optimizations["__strcpy_chk"] = &StrCpyChk;
Optimizations["__stpcpy_chk"] = &StpCpyChk;
Optimizations["cosf"] = &Cos;
Optimizations["cos"] = &Cos;
Optimizations["cosl"] = &Cos;
Optimizations["powf"] = &Pow;
Optimizations["pow"] = &Pow;
Optimizations["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;
Optimizations["exp2l"] = &Exp2;
Optimizations["exp2"] = &Exp2;
Optimizations["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;
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);
}
Optimizations["ffs"] = &FFS;
Optimizations["ffsl"] = &FFS;
Optimizations["ffsll"] = &FFS;
Optimizations["abs"] = &Abs;
Optimizations["labs"] = &Abs;
Optimizations["llabs"] = &Abs;
Optimizations["isdigit"] = &IsDigit;
Optimizations["isascii"] = &IsAscii;
Optimizations["toascii"] = &ToAscii;
Optimizations["sprintf"] = &SPrintF;
Optimizations["printf"] = &PrintF;
AddOpt(LibFunc::fwrite, &FWrite);
AddOpt(LibFunc::fputs, &FPuts);
Optimizations["fprintf"] = &FPrintF;
Optimizations["puts"] = &Puts;
}
bool SimplifyLibCalls::runOnFunction(Function &F) {
TLI = &getAnalysis<TargetLibraryInfo>();
if (Optimizations.empty())
InitOptimizations();
const TargetData *TD = getAnalysisIfAvailable<TargetData>();
IRBuilder<> Builder(F.getContext());
bool Changed = false;
for (Function::iterator BB = F.begin(), E = F.end(); BB != E; ++BB) {
for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E; ) {
CallInst *CI = dyn_cast<CallInst>(I++);
if (!CI) continue;
Function *Callee = CI->getCalledFunction();
if (Callee == 0 || !Callee->isDeclaration() ||
!(Callee->hasExternalLinkage() || Callee->hasDLLImportLinkage()))
continue;
LibCallOptimization *LCO = Optimizations.lookup(Callee->getName());
if (!LCO) continue;
Builder.SetInsertPoint(BB, I);
Builder.SetCurrentDebugLocation(CI->getDebugLoc());
Value *Result = LCO->OptimizeCall(CI, TD, TLI, Builder);
if (Result == 0) continue;
DEBUG(dbgs() << "SimplifyLibCalls simplified: " << *CI;
dbgs() << " into: " << *Result << "\n");
Changed = true;
++NumSimplified;
I = CI; ++I;
if (CI != Result && !CI->use_empty()) {
CI->replaceAllUsesWith(Result);
if (!Result->hasName())
Result->takeName(CI);
}
CI->eraseFromParent();
}
}
return Changed;
}
void SimplifyLibCalls::setDoesNotAccessMemory(Function &F) {
if (!F.doesNotAccessMemory()) {
F.setDoesNotAccessMemory();
++NumAnnotated;
Modified = true;
}
}
void SimplifyLibCalls::setOnlyReadsMemory(Function &F) {
if (!F.onlyReadsMemory()) {
F.setOnlyReadsMemory();
++NumAnnotated;
Modified = true;
}
}
void SimplifyLibCalls::setDoesNotThrow(Function &F) {
if (!F.doesNotThrow()) {
F.setDoesNotThrow();
++NumAnnotated;
Modified = true;
}
}
void SimplifyLibCalls::setDoesNotCapture(Function &F, unsigned n) {
if (!F.doesNotCapture(n)) {
F.setDoesNotCapture(n);
++NumAnnotated;
Modified = true;
}
}
void SimplifyLibCalls::setDoesNotAlias(Function &F, unsigned n) {
if (!F.doesNotAlias(n)) {
F.setDoesNotAlias(n);
++NumAnnotated;
Modified = true;
}
}
void SimplifyLibCalls::inferPrototypeAttributes(Function &F) {
FunctionType *FTy = F.getFunctionType();
StringRef Name = F.getName();
switch (Name[0]) {
case 's':
if (Name == "strlen") {
if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
return;
setOnlyReadsMemory(F);
setDoesNotThrow(F);
setDoesNotCapture(F, 1);
} else if (Name == "strchr" ||
Name == "strrchr") {
if (FTy->getNumParams() != 2 ||
!FTy->getParamType(0)->isPointerTy() ||
!FTy->getParamType(1)->isIntegerTy())
return;
setOnlyReadsMemory(F);
setDoesNotThrow(F);
} else if (Name == "strcpy" ||
Name == "stpcpy" ||
Name == "strcat" ||
Name == "strtol" ||
Name == "strtod" ||
Name == "strtof" ||
Name == "strtoul" ||
Name == "strtoll" ||
Name == "strtold" ||
Name == "strncat" ||
Name == "strncpy" ||
Name == "stpncpy" ||
Name == "strtoull") {
if (FTy->getNumParams() < 2 ||
!FTy->getParamType(1)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotCapture(F, 2);
} else if (Name == "strxfrm") {
if (FTy->getNumParams() != 3 ||
!FTy->getParamType(0)->isPointerTy() ||
!FTy->getParamType(1)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotCapture(F, 1);
setDoesNotCapture(F, 2);
} else if (Name == "strcmp" ||
Name == "strspn" ||
Name == "strncmp" ||
Name == "strcspn" ||
Name == "strcoll" ||
Name == "strcasecmp" ||
Name == "strncasecmp") {
if (FTy->getNumParams() < 2 ||
!FTy->getParamType(0)->isPointerTy() ||
!FTy->getParamType(1)->isPointerTy())
return;
setOnlyReadsMemory(F);
setDoesNotThrow(F);
setDoesNotCapture(F, 1);
setDoesNotCapture(F, 2);
} else if (Name == "strstr" ||
Name == "strpbrk") {
if (FTy->getNumParams() != 2 || !FTy->getParamType(1)->isPointerTy())
return;
setOnlyReadsMemory(F);
setDoesNotThrow(F);
setDoesNotCapture(F, 2);
} else if (Name == "strtok" ||
Name == "strtok_r") {
if (FTy->getNumParams() < 2 || !FTy->getParamType(1)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotCapture(F, 2);
} else if (Name == "scanf" ||
Name == "setbuf" ||
Name == "setvbuf") {
if (FTy->getNumParams() < 1 || !FTy->getParamType(0)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotCapture(F, 1);
} else if (Name == "strdup" ||
Name == "strndup") {
if (FTy->getNumParams() < 1 || !FTy->getReturnType()->isPointerTy() ||
!FTy->getParamType(0)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotAlias(F, 0);
setDoesNotCapture(F, 1);
} else if (Name == "stat" ||
Name == "sscanf" ||
Name == "sprintf" ||
Name == "statvfs") {
if (FTy->getNumParams() < 2 ||
!FTy->getParamType(0)->isPointerTy() ||
!FTy->getParamType(1)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotCapture(F, 1);
setDoesNotCapture(F, 2);
} else if (Name == "snprintf") {
if (FTy->getNumParams() != 3 ||
!FTy->getParamType(0)->isPointerTy() ||
!FTy->getParamType(2)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotCapture(F, 1);
setDoesNotCapture(F, 3);
} else if (Name == "setitimer") {
if (FTy->getNumParams() != 3 ||
!FTy->getParamType(1)->isPointerTy() ||
!FTy->getParamType(2)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotCapture(F, 2);
setDoesNotCapture(F, 3);
} else if (Name == "system") {
if (FTy->getNumParams() != 1 ||
!FTy->getParamType(0)->isPointerTy())
return;
setDoesNotCapture(F, 1);
}
break;
case 'm':
if (Name == "malloc") {
if (FTy->getNumParams() != 1 ||
!FTy->getReturnType()->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotAlias(F, 0);
} else if (Name == "memcmp") {
if (FTy->getNumParams() != 3 ||
!FTy->getParamType(0)->isPointerTy() ||
!FTy->getParamType(1)->isPointerTy())
return;
setOnlyReadsMemory(F);
setDoesNotThrow(F);
setDoesNotCapture(F, 1);
setDoesNotCapture(F, 2);
} else if (Name == "memchr" ||
Name == "memrchr") {
if (FTy->getNumParams() != 3)
return;
setOnlyReadsMemory(F);
setDoesNotThrow(F);
} else if (Name == "modf" ||
Name == "modff" ||
Name == "modfl" ||
Name == "memcpy" ||
Name == "memccpy" ||
Name == "memmove") {
if (FTy->getNumParams() < 2 ||
!FTy->getParamType(1)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotCapture(F, 2);
} else if (Name == "memalign") {
if (!FTy->getReturnType()->isPointerTy())
return;
setDoesNotAlias(F, 0);
} else if (Name == "mkdir" ||
Name == "mktime") {
if (FTy->getNumParams() == 0 ||
!FTy->getParamType(0)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotCapture(F, 1);
}
break;
case 'r':
if (Name == "realloc") {
if (FTy->getNumParams() != 2 ||
!FTy->getParamType(0)->isPointerTy() ||
!FTy->getReturnType()->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotAlias(F, 0);
setDoesNotCapture(F, 1);
} else if (Name == "read") {
if (FTy->getNumParams() != 3 ||
!FTy->getParamType(1)->isPointerTy())
return;
setDoesNotCapture(F, 2);
} else if (Name == "rmdir" ||
Name == "rewind" ||
Name == "remove" ||
Name == "realpath") {
if (FTy->getNumParams() < 1 ||
!FTy->getParamType(0)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotCapture(F, 1);
} else if (Name == "rename" ||
Name == "readlink") {
if (FTy->getNumParams() < 2 ||
!FTy->getParamType(0)->isPointerTy() ||
!FTy->getParamType(1)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotCapture(F, 1);
setDoesNotCapture(F, 2);
}
break;
case 'w':
if (Name == "write") {
if (FTy->getNumParams() != 3 || !FTy->getParamType(1)->isPointerTy())
return;
setDoesNotCapture(F, 2);
}
break;
case 'b':
if (Name == "bcopy") {
if (FTy->getNumParams() != 3 ||
!FTy->getParamType(0)->isPointerTy() ||
!FTy->getParamType(1)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotCapture(F, 1);
setDoesNotCapture(F, 2);
} else if (Name == "bcmp") {
if (FTy->getNumParams() != 3 ||
!FTy->getParamType(0)->isPointerTy() ||
!FTy->getParamType(1)->isPointerTy())
return;
setDoesNotThrow(F);
setOnlyReadsMemory(F);
setDoesNotCapture(F, 1);
setDoesNotCapture(F, 2);
} else if (Name == "bzero") {
if (FTy->getNumParams() != 2 || !FTy->getParamType(0)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotCapture(F, 1);
}
break;
case 'c':
if (Name == "calloc") {
if (FTy->getNumParams() != 2 ||
!FTy->getReturnType()->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotAlias(F, 0);
} else if (Name == "chmod" ||
Name == "chown" ||
Name == "ctermid" ||
Name == "clearerr" ||
Name == "closedir") {
if (FTy->getNumParams() == 0 || !FTy->getParamType(0)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotCapture(F, 1);
}
break;
case 'a':
if (Name == "atoi" ||
Name == "atol" ||
Name == "atof" ||
Name == "atoll") {
if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
return;
setDoesNotThrow(F);
setOnlyReadsMemory(F);
setDoesNotCapture(F, 1);
} else if (Name == "access") {
if (FTy->getNumParams() != 2 || !FTy->getParamType(0)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotCapture(F, 1);
}
break;
case 'f':
if (Name == "fopen") {
if (FTy->getNumParams() != 2 ||
!FTy->getReturnType()->isPointerTy() ||
!FTy->getParamType(0)->isPointerTy() ||
!FTy->getParamType(1)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotAlias(F, 0);
setDoesNotCapture(F, 1);
setDoesNotCapture(F, 2);
} else if (Name == "fdopen") {
if (FTy->getNumParams() != 2 ||
!FTy->getReturnType()->isPointerTy() ||
!FTy->getParamType(1)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotAlias(F, 0);
setDoesNotCapture(F, 2);
} else if (Name == "feof" ||
Name == "free" ||
Name == "fseek" ||
Name == "ftell" ||
Name == "fgetc" ||
Name == "fseeko" ||
Name == "ftello" ||
Name == "fileno" ||
Name == "fflush" ||
Name == "fclose" ||
Name == "fsetpos" ||
Name == "flockfile" ||
Name == "funlockfile" ||
Name == "ftrylockfile") {
if (FTy->getNumParams() == 0 || !FTy->getParamType(0)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotCapture(F, 1);
} else if (Name == "ferror") {
if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotCapture(F, 1);
setOnlyReadsMemory(F);
} else if (Name == "fputc" ||
Name == "fstat" ||
Name == "frexp" ||
Name == "frexpf" ||
Name == "frexpl" ||
Name == "fstatvfs") {
if (FTy->getNumParams() != 2 || !FTy->getParamType(1)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotCapture(F, 2);
} else if (Name == "fgets") {
if (FTy->getNumParams() != 3 ||
!FTy->getParamType(0)->isPointerTy() ||
!FTy->getParamType(2)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotCapture(F, 3);
} else if (Name == "fread" ||
Name == "fwrite") {
if (FTy->getNumParams() != 4 ||
!FTy->getParamType(0)->isPointerTy() ||
!FTy->getParamType(3)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotCapture(F, 1);
setDoesNotCapture(F, 4);
} else if (Name == "fputs" ||
Name == "fscanf" ||
Name == "fprintf" ||
Name == "fgetpos") {
if (FTy->getNumParams() < 2 ||
!FTy->getParamType(0)->isPointerTy() ||
!FTy->getParamType(1)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotCapture(F, 1);
setDoesNotCapture(F, 2);
}
break;
case 'g':
if (Name == "getc" ||
Name == "getlogin_r" ||
Name == "getc_unlocked") {
if (FTy->getNumParams() == 0 || !FTy->getParamType(0)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotCapture(F, 1);
} else if (Name == "getenv") {
if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
return;
setDoesNotThrow(F);
setOnlyReadsMemory(F);
setDoesNotCapture(F, 1);
} else if (Name == "gets" ||
Name == "getchar") {
setDoesNotThrow(F);
} else if (Name == "getitimer") {
if (FTy->getNumParams() != 2 || !FTy->getParamType(1)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotCapture(F, 2);
} else if (Name == "getpwnam") {
if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotCapture(F, 1);
}
break;
case 'u':
if (Name == "ungetc") {
if (FTy->getNumParams() != 2 || !FTy->getParamType(1)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotCapture(F, 2);
} else if (Name == "uname" ||
Name == "unlink" ||
Name == "unsetenv") {
if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotCapture(F, 1);
} else if (Name == "utime" ||
Name == "utimes") {
if (FTy->getNumParams() != 2 ||
!FTy->getParamType(0)->isPointerTy() ||
!FTy->getParamType(1)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotCapture(F, 1);
setDoesNotCapture(F, 2);
}
break;
case 'p':
if (Name == "putc") {
if (FTy->getNumParams() != 2 || !FTy->getParamType(1)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotCapture(F, 2);
} else if (Name == "puts" ||
Name == "printf" ||
Name == "perror") {
if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotCapture(F, 1);
} else if (Name == "pread" ||
Name == "pwrite") {
if (FTy->getNumParams() != 4 || !FTy->getParamType(1)->isPointerTy())
return;
setDoesNotCapture(F, 2);
} else if (Name == "putchar") {
setDoesNotThrow(F);
} else if (Name == "popen") {
if (FTy->getNumParams() != 2 ||
!FTy->getReturnType()->isPointerTy() ||
!FTy->getParamType(0)->isPointerTy() ||
!FTy->getParamType(1)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotAlias(F, 0);
setDoesNotCapture(F, 1);
setDoesNotCapture(F, 2);
} else if (Name == "pclose") {
if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotCapture(F, 1);
}
break;
case 'v':
if (Name == "vscanf") {
if (FTy->getNumParams() != 2 || !FTy->getParamType(1)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotCapture(F, 1);
} else if (Name == "vsscanf" ||
Name == "vfscanf") {
if (FTy->getNumParams() != 3 ||
!FTy->getParamType(1)->isPointerTy() ||
!FTy->getParamType(2)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotCapture(F, 1);
setDoesNotCapture(F, 2);
} else if (Name == "valloc") {
if (!FTy->getReturnType()->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotAlias(F, 0);
} else if (Name == "vprintf") {
if (FTy->getNumParams() != 2 || !FTy->getParamType(0)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotCapture(F, 1);
} else if (Name == "vfprintf" ||
Name == "vsprintf") {
if (FTy->getNumParams() != 3 ||
!FTy->getParamType(0)->isPointerTy() ||
!FTy->getParamType(1)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotCapture(F, 1);
setDoesNotCapture(F, 2);
} else if (Name == "vsnprintf") {
if (FTy->getNumParams() != 4 ||
!FTy->getParamType(0)->isPointerTy() ||
!FTy->getParamType(2)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotCapture(F, 1);
setDoesNotCapture(F, 3);
}
break;
case 'o':
if (Name == "open") {
if (FTy->getNumParams() < 2 || !FTy->getParamType(0)->isPointerTy())
return;
setDoesNotCapture(F, 1);
} else if (Name == "opendir") {
if (FTy->getNumParams() != 1 ||
!FTy->getReturnType()->isPointerTy() ||
!FTy->getParamType(0)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotAlias(F, 0);
setDoesNotCapture(F, 1);
}
break;
case 't':
if (Name == "tmpfile") {
if (!FTy->getReturnType()->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotAlias(F, 0);
} else if (Name == "times") {
if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotCapture(F, 1);
}
break;
case 'h':
if (Name == "htonl" ||
Name == "htons") {
setDoesNotThrow(F);
setDoesNotAccessMemory(F);
}
break;
case 'n':
if (Name == "ntohl" ||
Name == "ntohs") {
setDoesNotThrow(F);
setDoesNotAccessMemory(F);
}
break;
case 'l':
if (Name == "lstat") {
if (FTy->getNumParams() != 2 ||
!FTy->getParamType(0)->isPointerTy() ||
!FTy->getParamType(1)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotCapture(F, 1);
setDoesNotCapture(F, 2);
} else if (Name == "lchown") {
if (FTy->getNumParams() != 3 || !FTy->getParamType(0)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotCapture(F, 1);
}
break;
case 'q':
if (Name == "qsort") {
if (FTy->getNumParams() != 4 || !FTy->getParamType(3)->isPointerTy())
return;
setDoesNotCapture(F, 4);
}
break;
case '_':
if (Name == "__strdup" ||
Name == "__strndup") {
if (FTy->getNumParams() < 1 ||
!FTy->getReturnType()->isPointerTy() ||
!FTy->getParamType(0)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotAlias(F, 0);
setDoesNotCapture(F, 1);
} else if (Name == "__strtok_r") {
if (FTy->getNumParams() != 3 ||
!FTy->getParamType(1)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotCapture(F, 2);
} else if (Name == "_IO_getc") {
if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotCapture(F, 1);
} else if (Name == "_IO_putc") {
if (FTy->getNumParams() != 2 || !FTy->getParamType(1)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotCapture(F, 2);
}
break;
case 1:
if (Name == "\1__isoc99_scanf") {
if (FTy->getNumParams() < 1 ||
!FTy->getParamType(0)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotCapture(F, 1);
} else if (Name == "\1stat64" ||
Name == "\1lstat64" ||
Name == "\1statvfs64" ||
Name == "\1__isoc99_sscanf") {
if (FTy->getNumParams() < 1 ||
!FTy->getParamType(0)->isPointerTy() ||
!FTy->getParamType(1)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotCapture(F, 1);
setDoesNotCapture(F, 2);
} else if (Name == "\1fopen64") {
if (FTy->getNumParams() != 2 ||
!FTy->getReturnType()->isPointerTy() ||
!FTy->getParamType(0)->isPointerTy() ||
!FTy->getParamType(1)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotAlias(F, 0);
setDoesNotCapture(F, 1);
setDoesNotCapture(F, 2);
} else if (Name == "\1fseeko64" ||
Name == "\1ftello64") {
if (FTy->getNumParams() == 0 || !FTy->getParamType(0)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotCapture(F, 1);
} else if (Name == "\1tmpfile64") {
if (!FTy->getReturnType()->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotAlias(F, 0);
} else if (Name == "\1fstat64" ||
Name == "\1fstatvfs64") {
if (FTy->getNumParams() != 2 || !FTy->getParamType(1)->isPointerTy())
return;
setDoesNotThrow(F);
setDoesNotCapture(F, 2);
} else if (Name == "\1open64") {
if (FTy->getNumParams() < 2 || !FTy->getParamType(0)->isPointerTy())
return;
setDoesNotCapture(F, 1);
}
break;
}
}
bool SimplifyLibCalls::doInitialization(Module &M) {
Modified = false;
for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I) {
Function &F = *I;
if (F.isDeclaration() && F.hasName())
inferPrototypeAttributes(F);
}
return Modified;
}