[llvm] [X86] Improve optmasks handling for AVX10.1-256 (PR #73074)

[Simon Pilgrim via llvm-commits]

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@@ -5,6 +5,7 @@
 ; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mattr=+avx2 | FileCheck %s --check-prefixes=AVX,AVX1OR2,AVX2
 ; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mattr=+avx512f | FileCheck %s --check-prefixes=AVX,AVX512,KNL
 ; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mattr=+avx512vl,+avx512dq,+avx512bw | FileCheck %s --check-prefixes=AVX,AVX512,SKX
+; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mattr=+avx10.1-256 | FileCheck %s --check-prefixes=AVX,AVX10-256
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RKSimon wrote:

We can merge with a lot of existing checks if we did `--check-prefixes=AVX,AXV512,AVX10-256`

https://github.com/llvm/llvm-project/pull/73074