From 2593167b92dd2d27849e8bc331db2072a9b4bd7f Mon Sep 17 00:00:00 2001
From: Valentin Churavy <vchuravy@users.noreply.github.com>
Date: Mon, 4 Dec 2023 11:21:55 -0500
Subject: [PATCH] Block hoisting bitcasts over non-integral ascast (#23)

---
 llvm/lib/Transforms/InstCombine/InstCombineCasts.cpp | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/llvm/lib/Transforms/InstCombine/InstCombineCasts.cpp b/llvm/lib/Transforms/InstCombine/InstCombineCasts.cpp
index a9a930555b3c6..5f09f59cff7d6 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineCasts.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineCasts.cpp
@@ -2906,8 +2906,10 @@ Instruction *InstCombinerImpl::visitAddrSpaceCast(AddrSpaceCastInst &CI) {
   Value *Src = CI.getOperand(0);
   PointerType *SrcTy = cast<PointerType>(Src->getType()->getScalarType());
   PointerType *DestTy = cast<PointerType>(CI.getType()->getScalarType());
+  bool isni = DL.isNonIntegralAddressSpace(SrcTy->getAddressSpace()) ||
+              DL.isNonIntegralAddressSpace(DestTy->getAddressSpace());
 
-  if (!SrcTy->hasSameElementTypeAs(DestTy)) {
+  if (!SrcTy->hasSameElementTypeAs(DestTy) && !isni) {
     Type *MidTy =
         PointerType::getWithSamePointeeType(DestTy, SrcTy->getAddressSpace());
     // Handle vectors of pointers.