[llvm] [AMDGPU] si-peephole-sdwa: Disable V_CNDMASK_B32 conversion with sext (PR #140760)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,21 @@
+; RUN: llc -mtriple=amdgcn-amd-amdhsa -mcpu=gfx942 < %s | FileCheck %s
+; XFAIL: *
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arsenm wrote:

Don't use xfail 

https://github.com/llvm/llvm-project/pull/140760