[PATCH] D132634: [AArch64] Add index check before lowerInterleavedStore() uses ShuffleVectorInst's mask

[Peter Rong via Phabricator via llvm-commits]

Peter updated this revision to Diff 456721.
Peter added a comment.

Fixed format issue.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D132634/new/

https://reviews.llvm.org/D132634

Files:
  llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
  llvm/test/CodeGen/AArch64/aarch64-shufflevector.ll


Index: llvm/test/CodeGen/AArch64/aarch64-shufflevector.ll
===================================================================
--- /dev/null
+++ llvm/test/CodeGen/AArch64/aarch64-shufflevector.ll
@@ -0,0 +1,25 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+; RUN: llc -mtriple=aarch64-linux-gnu -opaque-pointers < %s | FileCheck %s
+
+target datalayout = "e-m:e-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128"
+target triple = "aarch64-unknown-linux-gnu"
+
+define void @f_undef(<8 x i64> %a, ptr %dst) {
+; CHECK-LABEL: f_undef:
+; CHECK:       // %bb.0: // %BB
+; CHECK-NEXT:    ret
+BB:
+  %S = shufflevector <8 x i64> %a, <8 x i64> %a, <16 x i32> undef
+  store <16 x i64> %S, ptr %dst, align 64
+  ret void
+}
+
+define void @f_poison(<8 x i64> %a, ptr %dst) {
+; CHECK-LABEL: f_poison:
+; CHECK:       // %bb.0: // %BB
+; CHECK-NEXT:    ret
+BB:
+  %S = shufflevector <8 x i64> %a, <8 x i64> %a, <16 x i32> poison
+  store <16 x i64> %S, ptr %dst, align 64
+  ret void
+}
Index: llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
===================================================================
--- llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
+++ llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
@@ -13363,6 +13363,13 @@
 
   auto Mask = SVI->getShuffleMask();
 
+  // Sanity check if all the indices are NOT in range.
+  // If mask is `undef` or `poison`, `Mask` may be a vector of -1s.
+  // If all of them are `undef`, OOB read will happen later.
+  if (llvm::all_of(Mask, [](int Idx) { return Idx == UndefMaskElem; })) {
+    return false;
+  }
+
   Type *PtrTy =
       UseScalable
           ? STVTy->getElementType()->getPointerTo(SI->getPointerAddressSpace())


-------------- next part --------------
A non-text attachment was scrubbed...
Name: D132634.456721.patch
Type: text/x-patch
Size: 1711 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20220830/f0f6f0d2/attachment.bin>