[llvm] [SelectionDAG] Fold low-prefix masked memops (PR #205118)

[Simon Pilgrim via llvm-commits]

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@@ -0,0 +1,134 @@
+; RUN: llc -mtriple=x86_64-apple-darwin -mattr=+avx512f,+avx512bw,+avx512vl < %s | FileCheck %s
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RKSimon wrote:

Please use the update script to generate checks
```suggestion
; RUN: llc -mtriple=x86_64-- -mattr=+avx512f,+avx512bw,+avx512vl < %s | FileCheck %s
```

https://github.com/llvm/llvm-project/pull/205118