/// EmitMemCmp - Emit a call to the memcmp function.
Value *EmitMemCmp(Value *Ptr1, Value *Ptr2, Value *Len, IRBuilder<> &B);
+ /// EmitMemSet - Emit a call to the memset function
+ Value *EmitMemSet(Value *Dst, Value *Val, Value *Len, IRBuilder<> &B);
+
/// EmitUnaryFloatFnCall - Emit a call to the unary function named 'Name' (e.g.
/// 'floor'). This function is known to take a single of type matching 'Op'
/// and returns one value with the same type. If 'Op' is a long double, 'l'
Len, "memcmp");
}
+/// EmitMemSet - Emit a call to the memset function
+Value *LibCallOptimization::EmitMemSet(Value *Dst, Value *Val,
+ Value *Len, IRBuilder<> &B) {
+ Module *M = Caller->getParent();
+ Intrinsic::ID IID = Intrinsic::memset;
+ const Type *Tys[1];
+ Tys[0] = Len->getType();
+ Value *MemSet = Intrinsic::getDeclaration(M, IID, Tys, 1);
+ Value *Align = ConstantInt::get(Type::Int32Ty, 1);
+ return B.CreateCall4(MemSet, CastToCStr(Dst, B), Val, Len, Align);
+}
+
/// EmitUnaryFloatFnCall - Emit a call to the unary function named 'Name' (e.g.
/// 'floor'). This function is known to take a single of type matching 'Op' and
/// returns one value with the same type. If 'Op' is a long double, 'l' is
if (Len == 0)
return Dst;
+ EmitStrLenMemCpy(Src, Dst, Len, B);
+ return Dst;
+ }
+
+ void EmitStrLenMemCpy(Value *Src, Value *Dst, uint64_t Len, IRBuilder<> &B) {
// We need to find the end of the destination string. That's where the
// memory is to be moved to. We just generate a call to strlen.
Value *DstLen = EmitStrLen(Dst, B);
// We have enough information to now generate the memcpy call to do the
// concatenation for us. Make a memcpy to copy the nul byte with align = 1.
EmitMemCpy(CpyDst, Src, ConstantInt::get(TD->getIntPtrType(), Len+1), 1, B);
+ }
+};
+
+//===---------------------------------------===//
+// 'strncat' Optimizations
+
+struct VISIBILITY_HIDDEN StrNCatOpt : public StrCatOpt {
+ virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+ // Verify the "strncat" function prototype.
+ const FunctionType *FT = Callee->getFunctionType();
+ if (FT->getNumParams() != 3 ||
+ FT->getReturnType() != PointerType::getUnqual(Type::Int8Ty) ||
+ FT->getParamType(0) != FT->getReturnType() ||
+ FT->getParamType(1) != FT->getReturnType() ||
+ !isa<IntegerType>(FT->getParamType(2)))
+ return 0;
+
+ // Extract some information from the instruction
+ Value *Dst = CI->getOperand(1);
+ Value *Src = CI->getOperand(2);
+ uint64_t Len;
+
+ // We don't do anything if length is not constant
+ if (ConstantInt *LengthArg = dyn_cast<ConstantInt>(CI->getOperand(3)))
+ Len = LengthArg->getZExtValue();
+ else
+ return 0;
+
+ // See if we can get the length of the input string.
+ uint64_t SrcLen = GetStringLength(Src);
+ if (SrcLen == 0) return 0;
+ --SrcLen; // Unbias length.
+
+ // Handle the simple, do-nothing cases:
+ // strncat(x, "", c) -> x
+ // strncat(x, c, 0) -> x
+ if (SrcLen == 0 || Len == 0) return Dst;
+
+ // We don't optimize this case
+ if (Len < SrcLen) return 0;
+
+ // strncat(x, s, c) -> strcat(x, s)
+ // s is constant so the strcat can be optimized further
+ EmitStrLenMemCpy(Src, Dst, Len, B);
return Dst;
}
};
}
};
+//===---------------------------------------===//
+// 'strncpy' Optimizations
+
+struct VISIBILITY_HIDDEN StrNCpyOpt : public LibCallOptimization {
+ virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+ const FunctionType *FT = Callee->getFunctionType();
+ if (FT->getNumParams() != 3 || FT->getReturnType() != FT->getParamType(0) ||
+ FT->getParamType(0) != FT->getParamType(1) ||
+ FT->getParamType(0) != PointerType::getUnqual(Type::Int8Ty) ||
+ !isa<IntegerType>(FT->getParamType(2)))
+ return 0;
+ Value *Dst = CI->getOperand(1);
+ Value *Src = CI->getOperand(2);
+ Value *LenOp = CI->getOperand(3);
+
+ // 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)
+ EmitMemSet(Dst, ConstantInt::get(Type::Int8Ty, '\0'), LenOp, B);
+ 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
+
+ // Let strncpy handle the zero padding
+ if (Len > SrcLen+1) return 0;
+
+ // strncpy(x, s, c) -> memcpy(x, s, c, 1) [s and c are constant]
+ EmitMemCpy(Dst, Src, ConstantInt::get(TD->getIntPtrType(), Len), 1, B);
+
+ return Dst;
+ }
+};
//===---------------------------------------===//
// 'strlen' Optimizations
return 0;
// memset(p, v, n) -> llvm.memset(p, v, n, 1)
- Module *M = Caller->getParent();
- Intrinsic::ID IID = Intrinsic::memset;
- const Type *Tys[1];
- Tys[0] = TD->getIntPtrType();
- Value *MemSet = Intrinsic::getDeclaration(M, IID, Tys, 1);
- Value *Dst = CastToCStr(CI->getOperand(1), B);
Value *Val = B.CreateTrunc(CI->getOperand(2), Type::Int8Ty);
- Value *Size = CI->getOperand(3);
- Value *Align = ConstantInt::get(Type::Int32Ty, 1);
- B.CreateCall4(MemSet, Dst, Val, Size, Align);
+ EmitMemSet(CI->getOperand(1), Val, CI->getOperand(3), B);
return CI->getOperand(1);
}
};
// Miscellaneous LibCall Optimizations
ExitOpt Exit;
// String and Memory LibCall Optimizations
- StrCatOpt StrCat; StrChrOpt StrChr; StrCmpOpt StrCmp; StrNCmpOpt StrNCmp;
- StrCpyOpt StrCpy; StrLenOpt StrLen; StrToOpt StrTo; MemCmpOpt MemCmp;
- MemCpyOpt MemCpy; MemMoveOpt MemMove; MemSetOpt MemSet;
+ StrCatOpt StrCat; StrNCatOpt StrNCat; StrChrOpt StrChr; StrCmpOpt StrCmp;
+ StrNCmpOpt StrNCmp; StrCpyOpt StrCpy; StrNCpyOpt StrNCpy; StrLenOpt StrLen;
+ StrToOpt StrTo; MemCmpOpt MemCmp; MemCpyOpt MemCpy; MemMoveOpt MemMove;
+ MemSetOpt MemSet;
// Math Library Optimizations
PowOpt Pow; Exp2Opt Exp2; UnaryDoubleFPOpt UnaryDoubleFP;
// Integer Optimizations
// String and Memory LibCall Optimizations
Optimizations["strcat"] = &StrCat;
+ Optimizations["strncat"] = &StrNCat;
Optimizations["strchr"] = &StrChr;
Optimizations["strcmp"] = &StrCmp;
Optimizations["strncmp"] = &StrNCmp;
Optimizations["strcpy"] = &StrCpy;
+ Optimizations["strncpy"] = &StrNCpy;
Optimizations["strlen"] = &StrLen;
Optimizations["strtol"] = &StrTo;
Optimizations["strtod"] = &StrTo;
// (if c is a constant integer and s is a constant string)
// * strrchr(s1,0) -> strchr(s1,0)
//
-// strncat:
-// * strncat(x,y,0) -> x
-// * strncat(x,y,0) -> x (if strlen(y) = 0)
-// * strncat(x,y,l) -> strcat(x,y) (if y and l are constants an l > strlen(y))
-//
-// strncpy:
-// * strncpy(d,s,0) -> d
-// * strncpy(d,s,l) -> memcpy(d,s,l,1)
-// (if s and l are constants)
-//
// strpbrk:
// * strpbrk(s,a) -> offset_in_for(s,a)
// (if s and a are both constant strings)
projects / oota-llvm.git / commitdiff