Commit af5faf89 authored by Sanjay Patel's avatar Sanjay Patel Committed by Tom Stellard
Browse files

[x86] avoid crashing when splitting AVX stores with non-simple type (PR43916) 

The store splitting transform was assuming a simple type (MVT),
but that's not necessarily the case as shown in the test.

(cherry picked from commit 8e34dd94)
parent 7fc9f129

llvm/lib/Target/X86/X86ISelLowering.cpp

+5 −3
Original line number Diff line number Diff line
@@ -21182,12 +21182,14 @@ static SDValue splitVectorStore(StoreSDNode *Store, SelectionDAG &DAG) { 
         "Expecting 256/512-bit op");















  // Splitting volatile memory ops is not allowed unless the operation was not













  // legal to begin with. We are assuming the input op is legal (this transform













  // is only used for targets with AVX).













  // legal to begin with. Assume the input store is legal (this transform is













  // only used for targets with AVX). Note: It is possible that we have an













  // illegal type like v2i128, and so we could allow splitting a volatile store













  // in that case if that is important.















  if (Store->isVolatile())















    return SDValue();



























  MVT StoreVT = StoredVal.getSimpleValueType();













  EVT StoreVT = StoredVal.getValueType();















  unsigned NumElems = StoreVT.getVectorNumElements();















  unsigned HalfSize = StoredVal.getValueSizeInBits() / 2;















  unsigned HalfAlign = (128 == HalfSize ? 16 : 32);

























llvm/test/CodeGen/X86/avx-load-store.ll



+23
−0






























Original line number
Diff line number
Diff line








@@ -333,3 +333,26 @@ define void @add4i64a16(<4 x i64>* %ret, <4 x i64>* %bp) nounwind {













  ret void















}





























; This used to crash.













; v2i128 may not be a "simple" (MVT) type, but we can split that.













; This example gets split further in legalization.



























define void @PR43916(<2 x i128> %y, <2 x i128>* %z) {













; CHECK-LABEL: PR43916:













; CHECK:       # %bb.0:













; CHECK-NEXT:    movq %rcx, 24(%r8)













; CHECK-NEXT:    movq %rdx, 16(%r8)













; CHECK-NEXT:    movq %rsi, 8(%r8)













; CHECK-NEXT:    movq %rdi, (%r8)













; CHECK-NEXT:    retq













;













; CHECK_O0-LABEL: PR43916:













; CHECK_O0:       # %bb.0:













; CHECK_O0-NEXT:    movq %rdi, (%r8)













; CHECK_O0-NEXT:    movq %rsi, 8(%r8)













; CHECK_O0-NEXT:    movq %rdx, 16(%r8)













; CHECK_O0-NEXT:    movq %rcx, 24(%r8)













; CHECK_O0-NEXT:    retq













  store <2 x i128> %y, <2 x i128>* %z, align 16













  ret void













}