[SimplifyLibCalls] Factor out fortified libcall handling.

This lets us remove CGP duplicate.

Differential Revision: http://reviews.llvm.org/D6541


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225640 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Ahmed Bougacha
2015-01-12 17:22:43 +00:00
parent fe2d64e0f6
commit 2cec3e9c11
5 changed files with 236 additions and 391 deletions

View File

@ -486,135 +486,3 @@ Value *llvm::EmitFWrite(Value *Ptr, Value *Size, Value *File,
CI->setCallingConv(Fn->getCallingConv());
return CI;
}
SimplifyFortifiedLibCalls::~SimplifyFortifiedLibCalls() { }
bool SimplifyFortifiedLibCalls::fold(CallInst *CI, const DataLayout *TD,
const TargetLibraryInfo *TLI) {
// We really need DataLayout for later.
if (!TD) return false;
this->CI = CI;
Function *Callee = CI->getCalledFunction();
StringRef Name = Callee->getName();
FunctionType *FT = Callee->getFunctionType();
LLVMContext &Context = CI->getParent()->getContext();
IRBuilder<> B(CI);
if (Name == "__memcpy_chk") {
// Check if this has the right signature.
if (FT->getNumParams() != 4 || FT->getReturnType() != FT->getParamType(0) ||
!FT->getParamType(0)->isPointerTy() ||
!FT->getParamType(1)->isPointerTy() ||
FT->getParamType(2) != TD->getIntPtrType(Context) ||
FT->getParamType(3) != TD->getIntPtrType(Context))
return false;
if (isFoldable(3, 2, false)) {
B.CreateMemCpy(CI->getArgOperand(0), CI->getArgOperand(1),
CI->getArgOperand(2), 1);
replaceCall(CI->getArgOperand(0));
return true;
}
return false;
}
// Should be similar to memcpy.
if (Name == "__mempcpy_chk") {
return false;
}
if (Name == "__memmove_chk") {
// Check if this has the right signature.
if (FT->getNumParams() != 4 || FT->getReturnType() != FT->getParamType(0) ||
!FT->getParamType(0)->isPointerTy() ||
!FT->getParamType(1)->isPointerTy() ||
FT->getParamType(2) != TD->getIntPtrType(Context) ||
FT->getParamType(3) != TD->getIntPtrType(Context))
return false;
if (isFoldable(3, 2, false)) {
B.CreateMemMove(CI->getArgOperand(0), CI->getArgOperand(1),
CI->getArgOperand(2), 1);
replaceCall(CI->getArgOperand(0));
return true;
}
return false;
}
if (Name == "__memset_chk") {
// Check if this has the right signature.
if (FT->getNumParams() != 4 || FT->getReturnType() != FT->getParamType(0) ||
!FT->getParamType(0)->isPointerTy() ||
!FT->getParamType(1)->isIntegerTy() ||
FT->getParamType(2) != TD->getIntPtrType(Context) ||
FT->getParamType(3) != TD->getIntPtrType(Context))
return false;
if (isFoldable(3, 2, false)) {
Value *Val = B.CreateIntCast(CI->getArgOperand(1), B.getInt8Ty(),
false);
B.CreateMemSet(CI->getArgOperand(0), Val, CI->getArgOperand(2), 1);
replaceCall(CI->getArgOperand(0));
return true;
}
return false;
}
if (Name == "__strcpy_chk" || Name == "__stpcpy_chk") {
// 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(Context))
return 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.
// 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));
if (!Ret)
return false;
replaceCall(Ret);
return true;
}
return false;
}
if (Name == "__strncpy_chk" || Name == "__stpncpy_chk") {
// Check if this has the right signature.
if (FT->getNumParams() != 4 || FT->getReturnType() != FT->getParamType(0) ||
FT->getParamType(0) != FT->getParamType(1) ||
FT->getParamType(0) != Type::getInt8PtrTy(Context) ||
!FT->getParamType(2)->isIntegerTy() ||
FT->getParamType(3) != TD->getIntPtrType(Context))
return false;
if (isFoldable(3, 2, false)) {
Value *Ret = EmitStrNCpy(CI->getArgOperand(0), CI->getArgOperand(1),
CI->getArgOperand(2), B, TD, TLI,
Name.substr(2, 7));
if (!Ret)
return false;
replaceCall(Ret);
return true;
}
return false;
}
if (Name == "__strcat_chk") {
return false;
}
if (Name == "__strncat_chk") {
return false;
}
return false;
}