[llvm] InferAddressSpaces: Stop trying to insert pointer bitcasts (PR #140873)

[Matt Arsenault via llvm-commits]

https://github.com/arsenm created https://github.com/llvm/llvm-project/pull/140873

None

>From 3f6f500e2b8c07d3f10ba9960f19dd7cebf08bc7 Mon Sep 17 00:00:00 2001
From: Matt Arsenault <Matthew.Arsenault at amd.com>
Date: Wed, 21 May 2025 11:33:53 +0200
Subject: [PATCH] InferAddressSpaces: Stop trying to insert pointer bitcasts

---
 llvm/lib/Transforms/Scalar/InferAddressSpaces.cpp | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/llvm/lib/Transforms/Scalar/InferAddressSpaces.cpp b/llvm/lib/Transforms/Scalar/InferAddressSpaces.cpp
index d3771c0903456..1b7cecc7ceb6a 100644
--- a/llvm/lib/Transforms/Scalar/InferAddressSpaces.cpp
+++ b/llvm/lib/Transforms/Scalar/InferAddressSpaces.cpp
@@ -660,8 +660,6 @@ Value *InferAddressSpacesImpl::cloneInstructionWithNewAddressSpace(
     // Therefore, the inferred address space must be the source space, according
     // to our algorithm.
     assert(Src->getType()->getPointerAddressSpace() == NewAddrSpace);
-    if (Src->getType() != NewPtrType)
-      return new BitCastInst(Src, NewPtrType);
     return Src;
   }
 
@@ -739,7 +737,7 @@ Value *InferAddressSpacesImpl::cloneInstructionWithNewAddressSpace(
     // If we had a no-op inttoptr/ptrtoint pair, we may still have inferred a
     // source address space from a generic pointer source need to insert a cast
     // back.
-    return CastInst::CreatePointerBitCastOrAddrSpaceCast(Src, NewPtrType);
+    return new AddrSpaceCastInst(Src, NewPtrType);
   }
   default:
     llvm_unreachable("Unexpected opcode");
@@ -764,7 +762,7 @@ static Value *cloneConstantExprWithNewAddressSpace(
     // to our algorithm.
     assert(CE->getOperand(0)->getType()->getPointerAddressSpace() ==
            NewAddrSpace);
-    return ConstantExpr::getBitCast(CE->getOperand(0), TargetType);
+    return CE->getOperand(0);
   }
 
   if (CE->getOpcode() == Instruction::BitCast) {
@@ -777,7 +775,7 @@ static Value *cloneConstantExprWithNewAddressSpace(
     assert(isNoopPtrIntCastPair(cast<Operator>(CE), *DL, TTI));
     Constant *Src = cast<ConstantExpr>(CE->getOperand(0))->getOperand(0);
     assert(Src->getType()->getPointerAddressSpace() == NewAddrSpace);
-    return ConstantExpr::getBitCast(Src, TargetType);
+    return Src;
   }
 
   // Computes the operands of the new constant expression.