[llvm] [HCS] Externd to outline overlapping sub/super cold regions (PR #80732)

[via llvm-commits]

hiraditya wrote:

In the meantime, do you mind reviewing why windows test failed? Maybe rebasing on top of main will fix it?

Any benchmark or performance numbers you have would also help motivate incorporating your changes.

https://github.com/llvm/llvm-project/pull/80732