[ConstantFold] Return the correct type when folding a GEP with vector indices.
As Eli pointed out (and I got wrong in the first place), langref says: "The
getelementptr returns a vector of pointers, instead of a single address, when one
or more of its arguments is a vector. In such cases, all vector arguments should
have the same number of elements, and every scalar argument will be effectively
broadcast into a vector during address calculation."
Costantfold for gep doesn't really take in account this paragraph, returning a
pointer instead of a vector of pointer which triggers an assertion in RAUW,
as we're trying to replace values with mistmatching types.
Differential Revision: https://reviews.llvm.org/D37928
llvm-svn: 313394
diff --git a/llvm/lib/IR/ConstantFold.cpp b/llvm/lib/IR/ConstantFold.cpp
index 311b0a7..60dd20e 100644
--- a/llvm/lib/IR/ConstantFold.cpp
+++ b/llvm/lib/IR/ConstantFold.cpp
@@ -2062,9 +2062,20 @@
Type *Ty = GetElementPtrInst::getIndexedType(PointeeTy, Idxs);
assert(Ty && "Invalid indices for GEP!");
+ Type *OrigGEPTy = PointerType::get(Ty, PtrTy->getAddressSpace());
Type *GEPTy = PointerType::get(Ty, PtrTy->getAddressSpace());
if (VectorType *VT = dyn_cast<VectorType>(C->getType()))
- GEPTy = VectorType::get(GEPTy, VT->getNumElements());
+ GEPTy = VectorType::get(OrigGEPTy, VT->getNumElements());
+
+ // The GEP returns a vector of pointers when one of more of
+ // its arguments is a vector.
+ for (unsigned i = 0, e = Idxs.size(); i != e; ++i) {
+ if (auto *VT = dyn_cast<VectorType>(Idxs[i]->getType())) {
+ GEPTy = VectorType::get(OrigGEPTy, VT->getNumElements());
+ break;
+ }
+ }
+
return Constant::getNullValue(GEPTy);
}
}