[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: *
+
+; FIXME The sext modifier is turned into a neg modifier in the asm output
+
+define i32 @test_select_on_sext_sdwa(i8 %x, i32 %y, i1 %cond)  {
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arsenm wrote:

The MIR test isn't really a substitute, particularly given that there are whole pipeline interactions with the final emission. Should bring back the IR test too 

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