[llvm] [X86] Handle undef/zero/ones cases after modifying Ops and Masks (PR #158428)

[Simon Pilgrim via llvm-commits]

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@@ -0,0 +1,38 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
+; RUN: llc < %s -mtriple=x86_64 -mattr=+avx2 | FileCheck %s
+
+define <32 x i16> @test(<8 x i8> %arg) {
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RKSimon wrote:

Better to add this to the end of the existing vector-shuffle-combining-avx2.ll file - with the test name changed to PR158415

https://github.com/llvm/llvm-project/pull/158428