[clang] [llvm] [OpenMP] Fix launch_bounds for OpenMP ompx_attribute (PR #195665)

[Shilei Tian via llvm-commits]

https://github.com/shiltian commented:

I can't add inline comment, but I'm not sure what the `IgnoreArch` does.

https://github.com/llvm/llvm-project/pull/195665