[clang] [Profile] Add binary profile correlation to offload profile metadata at runtime. (PR #69493)

[Zequan Wu via cfe-commits]

ZequanWu wrote:

> > > > This should works with PGO when value profiling is disabled
> > > 
> > > 
> > > Is this not compatible with value profiling? or just not implemented yet?
> > 
> > 
> > Not compatible, but this feature is mainly for coverage testing.
> 
> Ok, not a big deal as it's probably not worth the effort. But it would be nice if metadata can be separated out orthogonal to functionality, so things work in unified way with less special case. Just like debug info can be in a standalone binary (with gnu_debuglink), or in the original ELF binary, and they work equivalently for symbolization.

Ideally, prof name section in PGO can also be separated out as a strippable section. If we plan to separate PGO and code coverage stuff under compiler-rt/profile in the future. This is a good candidate as part of that effort.

https://github.com/llvm/llvm-project/pull/69493