[llvm] [AArch64][BTI] Add BTI at EH entries. (PR #155308)

[David Green via llvm-commits]

https://github.com/davemgreen commented:

Thanks. @ozbenh does this do OK in your testing?

@efriedma-quic @DanielKristofKiss does this sound OK to you? I'm not an expert with pacbti and exception handling, but it seems OK to me.

https://github.com/llvm/llvm-project/pull/155308