Do not change the type of a ByVal argument to a
type of a different size.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50121 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Scalar/InstructionCombining.cpp b/lib/Transforms/Scalar/InstructionCombining.cpp
index c201938..c2f4545 100644
--- a/lib/Transforms/Scalar/InstructionCombining.cpp
+++ b/lib/Transforms/Scalar/InstructionCombining.cpp
@@ -8748,16 +8748,29 @@
const PointerType *PTy = cast<PointerType>(Callee->getType());
const FunctionType *FTy = cast<FunctionType>(PTy->getElementType());
if (FTy->isVarArg()) {
+ int ix = FTy->getNumParams() + (isa<InvokeInst>(Callee) ? 3 : 1);
// See if we can optimize any arguments passed through the varargs area of
// the call.
for (CallSite::arg_iterator I = CS.arg_begin()+FTy->getNumParams(),
- E = CS.arg_end(); I != E; ++I)
+ E = CS.arg_end(); I != E; ++I, ++ix)
if (CastInst *CI = dyn_cast<CastInst>(*I)) {
- // If this cast does not effect the value passed through the varargs
+ // If this cast does not affect the value passed through the varargs
// area, we can eliminate the use of the cast.
- Value *Op = CI->getOperand(0);
+ const PointerType* SrcPTy, *DstPTy;
if (CI->isLosslessCast()) {
- *I = Op;
+ // The size of ByVal arguments is derived from the type, so we
+ // can't change to a type with a different size. If the size were
+ // passed explicitly we could avoid this check.
+ if (CS.paramHasAttr(ix, ParamAttr::ByVal) &&
+ (SrcPTy = cast<PointerType>(CI->getOperand(0)->getType())) &&
+ (DstPTy = cast<PointerType>(CI->getType()))) {
+ const Type* SrcTy = SrcPTy->getElementType();
+ const Type* DstTy = DstPTy->getElementType();
+ if (!SrcTy->isSized() || !DstTy->isSized() ||
+ TD->getABITypeSize(SrcTy) != TD->getABITypeSize(DstTy))
+ continue;
+ }
+ *I = CI->getOperand(0);
Changed = true;
}
}