[DAGCombiner] When folding (insert_subvector undef, (bitcast (extract_subvector N1, Idx)), Idx) -> (bitcast N1) make sure that N1 has the same total size as the original output
We were only checking the element count, but not the total width. This could cause illegal bitcasts to be created if for example the output was 512-bits, but N1 is 256 bits, and the extraction size was 128-bits. Fixes PR36199 Differential Revision: https://reviews.llvm.org/D42809 llvm-svn: 324002
This commit is contained in:
parent
cbc02c71a4
commit
a5944aade1
|
@ -16465,7 +16465,9 @@ SDValue DAGCombiner::visitINSERT_SUBVECTOR(SDNode *N) {
|
|||
N1.getOperand(0).getOpcode() == ISD::EXTRACT_SUBVECTOR &&
|
||||
N1.getOperand(0).getOperand(1) == N2 &&
|
||||
N1.getOperand(0).getOperand(0).getValueType().getVectorNumElements() ==
|
||||
VT.getVectorNumElements()) {
|
||||
VT.getVectorNumElements() &&
|
||||
N1.getOperand(0).getOperand(0).getValueType().getSizeInBits() ==
|
||||
VT.getSizeInBits()) {
|
||||
return DAG.getBitcast(VT, N1.getOperand(0).getOperand(0));
|
||||
}
|
||||
|
||||
|
|
|
@ -0,0 +1,22 @@
|
|||
; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
|
||||
; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mcpu=skylake-avx512 | FileCheck %s
|
||||
|
||||
define void @foo() unnamed_addr #0 {
|
||||
; CHECK-LABEL: foo:
|
||||
; CHECK: # %bb.0:
|
||||
; CHECK-NEXT: vaddps %zmm0, %zmm0, %zmm0
|
||||
; CHECK-NEXT: vinsertf128 $1, %xmm0, %ymm0, %ymm0
|
||||
; CHECK-NEXT: vinsertf64x4 $1, %ymm0, %zmm0, %zmm0
|
||||
; CHECK-NEXT: vmovups %zmm0, (%rax)
|
||||
; CHECK-NEXT: vzeroupper
|
||||
; CHECK-NEXT: retq
|
||||
%1 = fadd <16 x float> undef, undef
|
||||
%bc256 = bitcast <16 x float> %1 to <4 x i128>
|
||||
%2 = extractelement <4 x i128> %bc256, i32 0
|
||||
%3 = bitcast i128 %2 to <4 x float>
|
||||
%4 = shufflevector <4 x float> %3, <4 x float> undef, <16 x i32> <i32 0, i32
|
||||
1, i32 2, i32 3, i32 0, i32 1, i32 2, i32 3, i32 0, i32 1, i32 2, i32 3, i32 0,
|
||||
i32 1, i32 2, i32 3>
|
||||
store <16 x float> %4, <16 x float>* undef, align 4
|
||||
ret void
|
||||
}
|
Loading…
Reference in New Issue