[llvm] [X86][AVX512] Better lowering for `_mm512_maskz_shuffle_epi32` (PR #121147)

[Simon Pilgrim via llvm-commits]

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@@ -990,3 +990,23 @@ bb:
   ret void
 }
 
+define <8 x i64> @pr121147(<8 x i64> %a) {
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RKSimon wrote:

rename the test based off the shuffle mask and mention pr121147 as a comment.

https://github.com/llvm/llvm-project/pull/121147