[llvm] [Github][OpenMP] Adding rule for OpenMP label (PR #65331)

[Shilei Tian via llvm-commits]

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@@ -243,6 +243,10 @@ tools:llvm-mca:
   - llvm/include/llvm/MCA/**/*
   - llvm/lib/MCA/**/*
 
+openmp:
+  - mlir/**/OpenMP/*
+  - openmp/**
+
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shiltian wrote:

changes in clang will also be needed right?

https://github.com/llvm/llvm-project/pull/65331