[PowerPC] Darwin byval arguments are not immutable

On PPC/Darwin, byval arguments occur at fixed stack offsets in the callee's
frame, but are not immutable -- the pointer value is directly available to the
higher-level code as the address of the argument, and the value of the byval
argument can be modified at the IR level.

This is necessary, but not sufficient, to fix PR20280. When PR20280 is fixed in
a follow-up commit, its test case will cover this change.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215793 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Hal Finkel 2014-08-16 00:16:29 +00:00
parent 855d60236a
commit bdd8b6bfb9

View File

@ -3066,7 +3066,7 @@ PPCTargetLowering::LowerFormalArguments_Darwin(
CurArgOffset = CurArgOffset + (4 - ObjSize);
}
// The value of the object is its address.
int FI = MFI->CreateFixedObject(ObjSize, CurArgOffset, true);
int FI = MFI->CreateFixedObject(ObjSize, CurArgOffset, false);
SDValue FIN = DAG.getFrameIndex(FI, PtrVT);
InVals.push_back(FIN);
if (ObjSize==1 || ObjSize==2) {