fold gep undef, ... -> undef

This comes up many times in perlbmk and probably others.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@17100 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chris Lattner 2004-10-17 21:54:55 +00:00
parent ca45930548
commit cfbf9faaa4

View File

@ -1011,8 +1011,15 @@ Constant *llvm::ConstantFoldGetElementPtr(const Constant *C,
if (IdxList.size() == 0 ||
(IdxList.size() == 1 && cast<Constant>(IdxList[0])->isNullValue()))
return const_cast<Constant*>(C);
Constant *Idx0 = cast<Constant>(IdxList[0]);
if (isa<UndefValue>(C)) {
const Type *Ty = GetElementPtrInst::getIndexedType(C->getType(), IdxList,
true);
assert(Ty != 0 && "Invalid indices for GEP!");
return UndefValue::get(PointerType::get(Ty));
}
Constant *Idx0 = cast<Constant>(IdxList[0]);
if (C->isNullValue()) {
bool isNull = true;
for (unsigned i = 0, e = IdxList.size(); i != e; ++i)