[llvm] [InterleavedLoadCombine] Bail out on non-byte-sized vector element type (PR #90705)

[Nikita Popov via llvm-commits]

https://github.com/nikic created https://github.com/llvm/llvm-project/pull/90705

Vectors are always tightly packed, and elements of non-byte-sized usually do not have a well-defined (byte) offset.

Fixes https://github.com/llvm/llvm-project/issues/90695.

>From a42ea0d7774f0c6be67b93f7d30dddcc0d479453 Mon Sep 17 00:00:00 2001
From: Nikita Popov <npopov at redhat.com>
Date: Wed, 1 May 2024 14:41:28 +0900
Subject: [PATCH] [InterleavedLoadCombine] Bail out on non-byte-sized vector
 element type

Vectors are always tightly packed, and elements of non-byte-sized
usually do not have a well-defined (byte) offset.

Fixes https://github.com/llvm/llvm-project/issues/90695.
---
 .../CodeGen/InterleavedLoadCombinePass.cpp    |  3 +++
 .../interleaved-load-combine-pr90695.ll       | 19 +++++++++++++++++++
 2 files changed, 22 insertions(+)
 create mode 100644 llvm/test/CodeGen/AArch64/interleaved-load-combine-pr90695.ll

diff --git a/llvm/lib/CodeGen/InterleavedLoadCombinePass.cpp b/llvm/lib/CodeGen/InterleavedLoadCombinePass.cpp
index e5f164b182723f..a9b59e738c00bf 100644
--- a/llvm/lib/CodeGen/InterleavedLoadCombinePass.cpp
+++ b/llvm/lib/CodeGen/InterleavedLoadCombinePass.cpp
@@ -877,6 +877,9 @@ struct VectorInfo {
     if (LI->isAtomic())
       return false;
 
+    if (!DL.typeSizeEqualsStoreSize(Result.VTy->getElementType()))
+      return false;
+
     // Get the base polynomial
     computePolynomialFromPointer(*LI->getPointerOperand(), Offset, BasePtr, DL);
 
diff --git a/llvm/test/CodeGen/AArch64/interleaved-load-combine-pr90695.ll b/llvm/test/CodeGen/AArch64/interleaved-load-combine-pr90695.ll
new file mode 100644
index 00000000000000..ee75b3a083f713
--- /dev/null
+++ b/llvm/test/CodeGen/AArch64/interleaved-load-combine-pr90695.ll
@@ -0,0 +1,19 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 4
+; RUN: opt -S -passes=interleaved-load-combine < %s | FileCheck %s
+
+target triple = "aarch64-unknown-windows-gnu"
+
+; Make sure we don't crash on loads of vectors of non-byte-sized types.
+define <4 x i1> @test(ptr %p) {
+; CHECK-LABEL: define <4 x i1> @test(
+; CHECK-SAME: ptr [[P:%.*]]) {
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[LOAD:%.*]] = load <2 x i1>, ptr [[P]], align 1
+; CHECK-NEXT:    [[SHUF:%.*]] = shufflevector <2 x i1> [[LOAD]], <2 x i1> zeroinitializer, <4 x i32> <i32 0, i32 1, i32 2, i32 2>
+; CHECK-NEXT:    ret <4 x i1> [[SHUF]]
+;
+entry:
+  %load = load <2 x i1>, ptr %p, align 1
+  %shuf = shufflevector <2 x i1> %load, <2 x i1> zeroinitializer, <4 x i32> <i32 0, i32 1, i32 2, i32 2>
+  ret <4 x i1> %shuf
+}