[llvm] [SelectionDAG] Remove pointer from MMO for VP strided load/store. (PR #82667)

[Craig Topper via llvm-commits]

https://github.com/topperc updated https://github.com/llvm/llvm-project/pull/82667

>From 56ed060a823fee79b935ac50aabd3743940de3f9 Mon Sep 17 00:00:00 2001
From: Craig Topper <craig.topper at sifive.com>
Date: Thu, 22 Feb 2024 10:07:05 -0800
Subject: [PATCH 1/2] [SelectionDAG] Remove pointer from MMO for VP strided
 load/store.

MachineIR alias analysis assumes that only bytes after the pointer
will be accessed. This is incorrect if the stride is negative.
---
 llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
index e893a5b616d33e..3e53f3318a374a 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
@@ -8017,8 +8017,9 @@ void SelectionDAGBuilder::visitVPStridedLoad(
   MemoryLocation ML = MemoryLocation::getAfter(PtrOperand, AAInfo);
   bool AddToChain = !AA || !AA->pointsToConstantMemory(ML);
   SDValue InChain = AddToChain ? DAG.getRoot() : DAG.getEntryNode();
+  unsigned AS = PtrOperand->getPointerAddressSpace();
   MachineMemOperand *MMO = DAG.getMachineFunction().getMachineMemOperand(
-      MachinePointerInfo(PtrOperand), MachineMemOperand::MOLoad,
+      MachinePointerInfo(AS), MachineMemOperand::MOLoad,
       MemoryLocation::UnknownSize, *Alignment, AAInfo, Ranges);
 
   SDValue LD = DAG.getStridedLoadVP(VT, DL, InChain, OpValues[0], OpValues[1],
@@ -8039,8 +8040,9 @@ void SelectionDAGBuilder::visitVPStridedStore(
   if (!Alignment)
     Alignment = DAG.getEVTAlign(VT.getScalarType());
   AAMDNodes AAInfo = VPIntrin.getAAMetadata();
+  unsigned AS = PtrOperand->getPointerAddressSpace();
   MachineMemOperand *MMO = DAG.getMachineFunction().getMachineMemOperand(
-      MachinePointerInfo(PtrOperand), MachineMemOperand::MOStore,
+      MachinePointerInfo(AS), MachineMemOperand::MOStore,
       MemoryLocation::UnknownSize, *Alignment, AAInfo);
 
   SDValue ST = DAG.getStridedStoreVP(

>From b394b847b179cb9811a84ebf4f357403e90ee496 Mon Sep 17 00:00:00 2001
From: Craig Topper <craig.topper at sifive.com>
Date: Mon, 26 Feb 2024 13:46:24 -0800
Subject: [PATCH 2/2] fixup! Add missing getType calls.

---
 llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
index 3e53f3318a374a..fce92f12e14c48 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
@@ -8017,7 +8017,7 @@ void SelectionDAGBuilder::visitVPStridedLoad(
   MemoryLocation ML = MemoryLocation::getAfter(PtrOperand, AAInfo);
   bool AddToChain = !AA || !AA->pointsToConstantMemory(ML);
   SDValue InChain = AddToChain ? DAG.getRoot() : DAG.getEntryNode();
-  unsigned AS = PtrOperand->getPointerAddressSpace();
+  unsigned AS = PtrOperand->getType()->getPointerAddressSpace();
   MachineMemOperand *MMO = DAG.getMachineFunction().getMachineMemOperand(
       MachinePointerInfo(AS), MachineMemOperand::MOLoad,
       MemoryLocation::UnknownSize, *Alignment, AAInfo, Ranges);
@@ -8040,7 +8040,7 @@ void SelectionDAGBuilder::visitVPStridedStore(
   if (!Alignment)
     Alignment = DAG.getEVTAlign(VT.getScalarType());
   AAMDNodes AAInfo = VPIntrin.getAAMetadata();
-  unsigned AS = PtrOperand->getPointerAddressSpace();
+  unsigned AS = PtrOperand->getType()->getPointerAddressSpace();
   MachineMemOperand *MMO = DAG.getMachineFunction().getMachineMemOperand(
       MachinePointerInfo(AS), MachineMemOperand::MOStore,
       MemoryLocation::UnknownSize, *Alignment, AAInfo);