[llvm] [AMDGPU][True16][CodeGen] True16 Add OpSel when optimizing exec mask (PR #128928)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,64 @@
+# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py UTC_ARGS: --version 2
+# RUN: llc -march=amdgcn -mcpu=gfx1100 -mattr=+wavefrontsize64 -run-pass=si-optimize-exec-masking -verify-machineinstrs -o - %s | FileCheck %s
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arsenm wrote:

```suggestion
# RUN: llc -march=amdgcn -mcpu=gfx1100 -mattr=+wavefrontsize64 -run-pass=si-optimize-exec-masking -o - %s | FileCheck %s
```

https://github.com/llvm/llvm-project/pull/128928