When constant folding GEP expressions, keep the address space information of pointers.
Together with Ran Chachick <ran.chachick@intel.com>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160954 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/ConstantFolding.cpp b/lib/Analysis/ConstantFolding.cpp
index a7c9e55..f5e619c 100644
--- a/lib/Analysis/ConstantFolding.cpp
+++ b/lib/Analysis/ConstantFolding.cpp
@@ -603,6 +603,22 @@
return C;
}
+/// Strip the pointer casts, but preserve the address space information.
+static Constant* StripPtrCastKeepAS(Constant* Ptr) {
+ assert(Ptr->getType()->isPointerTy() && "Not a pointer type");
+ PointerType *OldPtrTy = cast<PointerType>(Ptr->getType());
+ Ptr = cast<Constant>(Ptr->stripPointerCasts());
+ PointerType *NewPtrTy = cast<PointerType>(Ptr->getType());
+
+ // Preserve the address space number of the pointer.
+ if (NewPtrTy->getAddressSpace() != OldPtrTy->getAddressSpace()) {
+ NewPtrTy = NewPtrTy->getElementType()->getPointerTo(
+ OldPtrTy->getAddressSpace());
+ Ptr = ConstantExpr::getBitCast(Ptr, NewPtrTy);
+ }
+ return Ptr;
+}
+
/// SymbolicallyEvaluateGEP - If we can symbolically evaluate the specified GEP
/// constant expression, do so.
static Constant *SymbolicallyEvaluateGEP(ArrayRef<Constant *> Ops,
@@ -639,13 +655,13 @@
}
return 0;
}
-
+
unsigned BitWidth = TD->getTypeSizeInBits(IntPtrTy);
APInt Offset =
APInt(BitWidth, TD->getIndexedOffset(Ptr->getType(),
makeArrayRef((Value **)Ops.data() + 1,
Ops.size() - 1)));
- Ptr = cast<Constant>(Ptr->stripPointerCasts());
+ Ptr = StripPtrCastKeepAS(Ptr);
// If this is a GEP of a GEP, fold it all into a single GEP.
while (GEPOperator *GEP = dyn_cast<GEPOperator>(Ptr)) {
@@ -664,7 +680,7 @@
Ptr = cast<Constant>(GEP->getOperand(0));
Offset += APInt(BitWidth,
TD->getIndexedOffset(Ptr->getType(), NestedOps));
- Ptr = cast<Constant>(Ptr->stripPointerCasts());
+ Ptr = StripPtrCastKeepAS(Ptr);
}
// If the base value for this address is a literal integer value, fold the