/// return value has 'intptr_t' type.
Value *EmitStrLen(Value *Ptr, IRBuilder<> &B);
+ /// EmitStrChr - Emit a call to the strchr function to the builder, for the
+ /// specified pointer and character. Ptr is required to be some pointer type,
+ /// and the return value has 'i8*' type.
+ Value *EmitStrChr(Value *Ptr, char C, IRBuilder<> &B);
+
/// EmitMemCpy - Emit a call to the memcpy function to the builder. This
/// always expects that the size has type 'intptr_t' and Dst/Src are pointers.
Value *EmitMemCpy(Value *Dst, Value *Src, Value *Len,
unsigned Align, IRBuilder<> &B);
+ /// EmitMemMove - Emit a call to the memmove function to the builder. This
+ /// always expects that the size has type 'intptr_t' and Dst/Src are pointers.
+ Value *EmitMemMove(Value *Dst, Value *Src, Value *Len,
+ unsigned Align, IRBuilder<> &B);
+
/// EmitMemChr - Emit a call to the memchr function. This assumes that Ptr is
/// a pointer, Val is an i32 value, and Len is an 'intptr_t' value.
Value *EmitMemChr(Value *Ptr, Value *Val, 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'
- /// is added as the suffix of name, if 'Op' is a float, we add a 'f' suffix.
+ /// 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 added as the suffix of name, if 'Op' is a float, we add a 'f'
+ /// suffix.
Value *EmitUnaryFloatFnCall(Value *Op, const char *Name, IRBuilder<> &B,
const AttrListPtr &Attrs);
/// EmitPutChar - Emit a call to the putchar function. This assumes that Char
/// is an integer.
- void EmitPutChar(Value *Char, IRBuilder<> &B);
+ Value *EmitPutChar(Value *Char, IRBuilder<> &B);
/// EmitPutS - Emit a call to the puts function. This assumes that Str is
/// some pointer.
/// CastToCStr - Return V if it is an i8*, otherwise cast it to i8*.
Value *LibCallOptimization::CastToCStr(Value *V, IRBuilder<> &B) {
- return
- B.CreateBitCast(V, Type::getInt8PtrTy(*Context), "cstr");
+ return B.CreateBitCast(V, Type::getInt8PtrTy(*Context), "cstr");
}
/// EmitStrLen - Emit a call to the strlen function to the builder, for the
return CI;
}
+/// EmitStrChr - Emit a call to the strchr function to the builder, for the
+/// specified pointer and character. Ptr is required to be some pointer type,
+/// and the return value has 'i8*' type.
+Value *LibCallOptimization::EmitStrChr(Value *Ptr, char C, IRBuilder<> &B) {
+ Module *M = Caller->getParent();
+ AttributeWithIndex AWI =
+ AttributeWithIndex::get(~0u, Attribute::ReadOnly | Attribute::NoUnwind);
+
+ const Type *I8Ptr = Type::getInt8PtrTy(*Context);
+ const Type *I32Ty = Type::getInt32Ty(*Context);
+ Constant *StrChr = M->getOrInsertFunction("strchr", AttrListPtr::get(&AWI, 1),
+ I8Ptr, I8Ptr, I32Ty, NULL);
+ CallInst *CI = B.CreateCall2(StrChr, CastToCStr(Ptr, B),
+ ConstantInt::get(I32Ty, C), "strchr");
+ if (const Function *F = dyn_cast<Function>(StrChr->stripPointerCasts()))
+ CI->setCallingConv(F->getCallingConv());
+ return CI;
+}
+
+
/// EmitMemCpy - Emit a call to the memcpy function to the builder. This always
/// expects that the size has type 'intptr_t' and Dst/Src are pointers.
Value *LibCallOptimization::EmitMemCpy(Value *Dst, Value *Src, Value *Len,
unsigned Align, IRBuilder<> &B) {
Module *M = Caller->getParent();
- Intrinsic::ID IID = Intrinsic::memcpy;
- const Type *Tys[1];
- Tys[0] = Len->getType();
- Value *MemCpy = Intrinsic::getDeclaration(M, IID, Tys, 1);
- return B.CreateCall4(MemCpy, CastToCStr(Dst, B), CastToCStr(Src, B), Len,
+ const Type *Ty = Len->getType();
+ Value *MemCpy = Intrinsic::getDeclaration(M, Intrinsic::memcpy, &Ty, 1);
+ Dst = CastToCStr(Dst, B);
+ Src = CastToCStr(Src, B);
+ return B.CreateCall4(MemCpy, Dst, Src, Len,
ConstantInt::get(Type::getInt32Ty(*Context), Align));
}
+/// EmitMemMove - Emit a call to the memmove function to the builder. This
+/// always expects that the size has type 'intptr_t' and Dst/Src are pointers.
+Value *LibCallOptimization::EmitMemMove(Value *Dst, Value *Src, Value *Len,
+ unsigned Align, IRBuilder<> &B) {
+ Module *M = Caller->getParent();
+ const Type *Ty = TD->getIntPtrType(*Context);
+ Value *MemMove = Intrinsic::getDeclaration(M, Intrinsic::memmove, &Ty, 1);
+ Dst = CastToCStr(Dst, B);
+ Src = CastToCStr(Src, B);
+ Value *A = ConstantInt::get(Type::getInt32Ty(*Context), Align);
+ return B.CreateCall4(MemMove, Dst, Src, Len, A);
+}
+
/// EmitMemChr - Emit a call to the memchr function. This assumes that Ptr is
/// a pointer, Val is an i32 value, and Len is an 'intptr_t' value.
Value *LibCallOptimization::EmitMemChr(Value *Ptr, Value *Val,
/// EmitPutChar - Emit a call to the putchar function. This assumes that Char
/// is an integer.
-void LibCallOptimization::EmitPutChar(Value *Char, IRBuilder<> &B) {
+Value *LibCallOptimization::EmitPutChar(Value *Char, IRBuilder<> &B) {
Module *M = Caller->getParent();
Value *PutChar = M->getOrInsertFunction("putchar", Type::getInt32Ty(*Context),
Type::getInt32Ty(*Context), NULL);
CallInst *CI = B.CreateCall(PutChar,
B.CreateIntCast(Char,
Type::getInt32Ty(*Context),
+ /*isSigned*/true,
"chari"),
"putchar");
if (const Function *F = dyn_cast<Function>(PutChar->stripPointerCasts()))
CI->setCallingConv(F->getCallingConv());
+ return CI;
}
/// EmitPutS - Emit a call to the puts function. This assumes that Str is
Type::getInt32Ty(*Context),
Type::getInt32Ty(*Context),
File->getType(), NULL);
- Char = B.CreateIntCast(Char, Type::getInt32Ty(*Context), "chari");
+ Char = B.CreateIntCast(Char, Type::getInt32Ty(*Context), /*isSigned*/true,
+ "chari");
CallInst *CI = B.CreateCall2(F, Char, File, "fputc");
if (const Function *Fn = dyn_cast<Function>(F->stripPointerCasts()))
return true;
}
-//===----------------------------------------------------------------------===//
-// Miscellaneous LibCall/Intrinsic Optimizations
-//===----------------------------------------------------------------------===//
-
-namespace {
-struct SizeOpt : public LibCallOptimization {
- virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
- // TODO: We can do more with this, but delaying to here should be no change
- // in behavior.
- ConstantInt *Const = dyn_cast<ConstantInt>(CI->getOperand(2));
-
- if (!Const) return 0;
-
- if (Const->getZExtValue() < 2)
- return Constant::getAllOnesValue(Const->getType());
- else
- return ConstantInt::get(Const->getType(), 0);
- }
-};
-}
-
//===----------------------------------------------------------------------===//
// String and Memory LibCall Optimizations
//===----------------------------------------------------------------------===//
uint64_t Len = GetStringLength(SrcStr);
if (Len == 0 ||
- FT->getParamType(1) != Type::getInt32Ty(*Context)) // memchr needs i32.
+ FT->getParamType(1) != Type::getInt32Ty(*Context)) // memchr needs
+ // i32.
return 0;
return EmitMemChr(SrcStr, CI->getOperand(2), // include nul.
if (uint64_t Len = GetStringLength(Src))
return ConstantInt::get(CI->getType(), Len-1);
- // Handle strlen(p) != 0.
- if (!IsOnlyUsedInZeroEqualityComparison(CI)) return 0;
-
// strlen(x) != 0 --> *x != 0
// strlen(x) == 0 --> *x == 0
- return B.CreateZExt(B.CreateLoad(Src, "strlenfirst"), CI->getType());
+ if (IsOnlyUsedInZeroEqualityComparison(CI))
+ return B.CreateZExt(B.CreateLoad(Src, "strlenfirst"), CI->getType());
+ return 0;
}
};
//===---------------------------------------===//
-// 'strto*' Optimizations
+// 'strto*' Optimizations. This handles strtol, strtod, strtof, strtoul, etc.
struct StrToOpt : public LibCallOptimization {
virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
}
};
+//===---------------------------------------===//
+// 'strstr' Optimizations
+
+struct StrStrOpt : public LibCallOptimization {
+ virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+ const FunctionType *FT = Callee->getFunctionType();
+ if (FT->getNumParams() != 2 ||
+ !isa<PointerType>(FT->getParamType(0)) ||
+ !isa<PointerType>(FT->getParamType(1)) ||
+ !isa<PointerType>(FT->getReturnType()))
+ return 0;
+
+ // fold strstr(x, x) -> x.
+ if (CI->getOperand(1) == CI->getOperand(2))
+ return B.CreateBitCast(CI->getOperand(1), CI->getType());
+
+ // See if either input string is a constant string.
+ std::string SearchStr, ToFindStr;
+ bool HasStr1 = GetConstantStringInfo(CI->getOperand(1), SearchStr);
+ bool HasStr2 = GetConstantStringInfo(CI->getOperand(2), ToFindStr);
+
+ // fold strstr(x, "") -> x.
+ if (HasStr2 && ToFindStr.empty())
+ return B.CreateBitCast(CI->getOperand(1), CI->getType());
+
+ // If both strings are known, constant fold it.
+ if (HasStr1 && HasStr2) {
+ std::string::size_type Offset = SearchStr.find(ToFindStr);
+
+ if (Offset == std::string::npos) // strstr("foo", "bar") -> null
+ return Constant::getNullValue(CI->getType());
+
+ // strstr("abcd", "bc") -> gep((char*)"abcd", 1)
+ Value *Result = CastToCStr(CI->getOperand(1), 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)
+ return B.CreateBitCast(EmitStrChr(CI->getOperand(1), ToFindStr[0], B),
+ CI->getType());
+ return 0;
+ }
+};
+
//===---------------------------------------===//
// 'memcmp' Optimizations
return B.CreateSExt(B.CreateSub(LHSV, RHSV, "chardiff"), CI->getType());
}
- // memcmp(S1,S2,2) != 0 -> (*(short*)LHS ^ *(short*)RHS) != 0
- // memcmp(S1,S2,4) != 0 -> (*(int*)LHS ^ *(int*)RHS) != 0
- if ((Len == 2 || Len == 4) && IsOnlyUsedInZeroEqualityComparison(CI)) {
- const Type *PTy = PointerType::getUnqual(Len == 2 ?
- Type::getInt16Ty(*Context) : Type::getInt32Ty(*Context));
- LHS = B.CreateBitCast(LHS, PTy, "tmp");
- RHS = B.CreateBitCast(RHS, PTy, "tmp");
- LoadInst *LHSV = B.CreateLoad(LHS, "lhsv");
- LoadInst *RHSV = B.CreateLoad(RHS, "rhsv");
- LHSV->setAlignment(1); RHSV->setAlignment(1); // Unaligned loads.
- return B.CreateZExt(B.CreateXor(LHSV, RHSV, "shortdiff"), CI->getType());
+ // Constant folding: memcmp(x, y, l) -> cnst (all arguments are constant)
+ std::string LHSStr, RHSStr;
+ if (GetConstantStringInfo(LHS, LHSStr) &&
+ GetConstantStringInfo(RHS, RHSStr)) {
+ // Make sure we're not reading out-of-bounds memory.
+ if (Len > LHSStr.length() || Len > RHSStr.length())
+ return 0;
+ uint64_t Ret = memcmp(LHSStr.data(), RHSStr.data(), Len);
+ return ConstantInt::get(CI->getType(), Ret);
}
return 0;
return 0;
// memmove(x, y, n) -> llvm.memmove(x, y, n, 1)
- Module *M = Caller->getParent();
- Intrinsic::ID IID = Intrinsic::memmove;
- const Type *Tys[1];
- Tys[0] = TD->getIntPtrType(*Context);
- Value *MemMove = Intrinsic::getDeclaration(M, IID, Tys, 1);
- Value *Dst = CastToCStr(CI->getOperand(1), B);
- Value *Src = CastToCStr(CI->getOperand(2), B);
- Value *Size = CI->getOperand(3);
- Value *Align = ConstantInt::get(Type::getInt32Ty(*Context), 1);
- B.CreateCall4(MemMove, Dst, Src, Size, Align);
+ EmitMemMove(CI->getOperand(1), CI->getOperand(2), CI->getOperand(3), 1, B);
return CI->getOperand(1);
}
};
}
};
+//===----------------------------------------------------------------------===//
+// Object Size Checking Optimizations
+//===----------------------------------------------------------------------===//
+
+//===---------------------------------------===//
+// 'object size'
+namespace {
+struct SizeOpt : public LibCallOptimization {
+ virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+ // TODO: We can do more with this, but delaying to here should be no change
+ // in behavior.
+ ConstantInt *Const = dyn_cast<ConstantInt>(CI->getOperand(2));
+
+ if (!Const) return 0;
+
+ const Type *Ty = Callee->getFunctionType()->getReturnType();
+
+ if (Const->getZExtValue() == 0)
+ return Constant::getAllOnesValue(Ty);
+ else
+ return ConstantInt::get(Ty, 0);
+ }
+};
+}
+
+//===---------------------------------------===//
+// 'memcpy_chk' Optimizations
+
+struct MemCpyChkOpt : public LibCallOptimization {
+ virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+ // These optimizations require TargetData.
+ if (!TD) return 0;
+
+ const FunctionType *FT = Callee->getFunctionType();
+ if (FT->getNumParams() != 4 || FT->getReturnType() != FT->getParamType(0) ||
+ !isa<PointerType>(FT->getParamType(0)) ||
+ !isa<PointerType>(FT->getParamType(1)) ||
+ !isa<IntegerType>(FT->getParamType(3)) ||
+ FT->getParamType(2) != TD->getIntPtrType(*Context))
+ return 0;
+
+ ConstantInt *SizeCI = dyn_cast<ConstantInt>(CI->getOperand(4));
+ if (!SizeCI)
+ return 0;
+ if (SizeCI->isAllOnesValue()) {
+ EmitMemCpy(CI->getOperand(1), CI->getOperand(2), CI->getOperand(3), 1, B);
+ return CI->getOperand(1);
+ }
+
+ return 0;
+ }
+};
+
+//===---------------------------------------===//
+// 'memset_chk' Optimizations
+
+struct MemSetChkOpt : public LibCallOptimization {
+ virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+ // These optimizations require TargetData.
+ if (!TD) return 0;
+
+ const FunctionType *FT = Callee->getFunctionType();
+ if (FT->getNumParams() != 4 || FT->getReturnType() != FT->getParamType(0) ||
+ !isa<PointerType>(FT->getParamType(0)) ||
+ !isa<IntegerType>(FT->getParamType(1)) ||
+ !isa<IntegerType>(FT->getParamType(3)) ||
+ FT->getParamType(2) != TD->getIntPtrType(*Context))
+ return 0;
+
+ ConstantInt *SizeCI = dyn_cast<ConstantInt>(CI->getOperand(4));
+ if (!SizeCI)
+ return 0;
+ if (SizeCI->isAllOnesValue()) {
+ Value *Val = B.CreateIntCast(CI->getOperand(2), Type::getInt8Ty(*Context),
+ false);
+ EmitMemSet(CI->getOperand(1), Val, CI->getOperand(3), B);
+ return CI->getOperand(1);
+ }
+
+ return 0;
+ }
+};
+
+//===---------------------------------------===//
+// 'memmove_chk' Optimizations
+
+struct MemMoveChkOpt : public LibCallOptimization {
+ virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
+ // These optimizations require TargetData.
+ if (!TD) return 0;
+
+ const FunctionType *FT = Callee->getFunctionType();
+ if (FT->getNumParams() != 4 || FT->getReturnType() != FT->getParamType(0) ||
+ !isa<PointerType>(FT->getParamType(0)) ||
+ !isa<PointerType>(FT->getParamType(1)) ||
+ !isa<IntegerType>(FT->getParamType(3)) ||
+ FT->getParamType(2) != TD->getIntPtrType(*Context))
+ return 0;
+
+ ConstantInt *SizeCI = dyn_cast<ConstantInt>(CI->getOperand(4));
+ if (!SizeCI)
+ return 0;
+ if (SizeCI->isAllOnesValue()) {
+ EmitMemMove(CI->getOperand(1), CI->getOperand(2), CI->getOperand(3),
+ 1, B);
+ return CI->getOperand(1);
+ }
+
+ return 0;
+ }
+};
+
//===----------------------------------------------------------------------===//
// Math Library Optimizations
//===----------------------------------------------------------------------===//
return CI->use_empty() ? (Value*)CI :
ConstantInt::get(CI->getType(), 0);
- // printf("x") -> putchar('x'), even for '%'.
+ // printf("x") -> putchar('x'), even for '%'. Return the result of putchar
+ // in case there is an error writing to stdout.
if (FormatStr.size() == 1) {
- EmitPutChar(ConstantInt::get(Type::getInt32Ty(*Context), FormatStr[0]), B);
- return CI->use_empty() ? (Value*)CI :
- ConstantInt::get(CI->getType(), 1);
+ Value *Res = EmitPutChar(ConstantInt::get(Type::getInt32Ty(*Context),
+ FormatStr[0]), B);
+ if (CI->use_empty()) return CI;
+ return B.CreateIntCast(Res, CI->getType(), true);
}
// printf("foo\n") --> puts("foo")
// printf("%c", chr) --> putchar(*(i8*)dst)
if (FormatStr == "%c" && CI->getNumOperands() > 2 &&
isa<IntegerType>(CI->getOperand(2)->getType())) {
- EmitPutChar(CI->getOperand(2), B);
- return CI->use_empty() ? (Value*)CI :
- ConstantInt::get(CI->getType(), 1);
+ Value *Res = EmitPutChar(CI->getOperand(2), B);
+
+ if (CI->use_empty()) return CI;
+ return B.CreateIntCast(Res, CI->getType(), true);
}
// printf("%s\n", str) --> puts(str)
// sprintf(str, fmt) -> llvm.memcpy(str, fmt, strlen(fmt)+1, 1)
EmitMemCpy(CI->getOperand(1), CI->getOperand(2), // Copy the nul byte.
- ConstantInt::get(TD->getIntPtrType(*Context), FormatStr.size()+1),1,B);
+ ConstantInt::get
+ (TD->getIntPtrType(*Context), FormatStr.size()+1),1,B);
return ConstantInt::get(CI->getType(), FormatStr.size());
}
// These optimizations require TargetData.
if (!TD) return 0;
- EmitFWrite(CI->getOperand(2), ConstantInt::get(TD->getIntPtrType(*Context),
- FormatStr.size()),
+ EmitFWrite(CI->getOperand(2),
+ ConstantInt::get(TD->getIntPtrType(*Context),
+ FormatStr.size()),
CI->getOperand(1), B);
return ConstantInt::get(CI->getType(), FormatStr.size());
}
// String and Memory LibCall Optimizations
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;
+ StrToOpt StrTo; StrStrOpt StrStr;
+ MemCmpOpt MemCmp; MemCpyOpt MemCpy; MemMoveOpt MemMove; MemSetOpt MemSet;
// Math Library Optimizations
PowOpt Pow; Exp2Opt Exp2; UnaryDoubleFPOpt UnaryDoubleFP;
// Integer Optimizations
// Formatting and IO Optimizations
SPrintFOpt SPrintF; PrintFOpt PrintF;
FWriteOpt FWrite; FPutsOpt FPuts; FPrintFOpt FPrintF;
+
+ // Object Size Checking
SizeOpt ObjectSize;
+ MemCpyChkOpt MemCpyChk; MemSetChkOpt MemSetChk; MemMoveChkOpt MemMoveChk;
bool Modified; // This is only used by doInitialization.
public:
Optimizations["strtoll"] = &StrTo;
Optimizations["strtold"] = &StrTo;
Optimizations["strtoull"] = &StrTo;
+ Optimizations["strstr"] = &StrStr;
Optimizations["memcmp"] = &MemCmp;
Optimizations["memcpy"] = &MemCpy;
Optimizations["memmove"] = &MemMove;
Optimizations["fwrite"] = &FWrite;
Optimizations["fputs"] = &FPuts;
Optimizations["fprintf"] = &FPrintF;
-
- // Miscellaneous
- Optimizations["llvm.objectsize"] = &ObjectSize;
+
+ // Object Size Checking
+ Optimizations["llvm.objectsize.i32"] = &ObjectSize;
+ Optimizations["llvm.objectsize.i64"] = &ObjectSize;
+ Optimizations["__memcpy_chk"] = &MemCpyChk;
+ Optimizations["__memset_chk"] = &MemSetChk;
+ Optimizations["__memmove_chk"] = &MemMoveChk;
}
Value *Result = LCO->OptimizeCall(CI, TD, Builder);
if (Result == 0) continue;
- DEBUG(errs() << "SimplifyLibCalls simplified: " << *CI;
- errs() << " into: " << *Result << "\n");
+ DEBUG(dbgs() << "SimplifyLibCalls simplified: " << *CI;
+ dbgs() << " into: " << *Result << "\n");
// Something changed!
Changed = true;
// lround, lroundf, lroundl:
// * lround(cnst) -> cnst'
//
-// memcmp:
-// * memcmp(x,y,l) -> cnst
-// (if all arguments are constant and strlen(x) <= l and strlen(y) <= l)
-//
// pow, powf, powl:
// * pow(exp(x),y) -> exp(x*y)
// * pow(sqrt(x),y) -> pow(x,y*0.5)
// * strcspn("",a) -> 0
// * strcspn(s,"") -> strlen(a)
//
-// strstr:
-// * strstr(x,x) -> x
-// * strstr(s1,s2) -> offset_of_s2_in(s1)
-// (if s1 and s2 are constant strings)
-//
// tan, tanf, tanl:
// * tan(atan(x)) -> x
//