[clang] [compiler-rt] [llvm] [InstrFDO][TypeProf] Implement binary instrumentation and profile read/write (PR #66825)

[Snehasish Kumar via cfe-commits]

snehasish wrote:

> > Here are some things I noticed, haven't looked at the tests yet.
> 
> @snehasish Thanks for the review!
> 
> Talking about tests, I wonder if it looks better if I change the current LLVM IR test under `llvm/test/tools/llvm-profdata/` into a compiler-rt test under `compiler-rt/test/profile/Linux`, demonstrated in [167d5ce](https://github.com/llvm/llvm-project/commit/167d5ce49e41ca098085cda315687ade194981b1)
> 

My concern with this approach is that compiler-rt is treated as a different project and updating the code within LLVM makes it easy to miss running the test locally for the other project. I think such issues will be caught by the buildbot but having it flagged earlier is better for the developer. What do you think?

https://github.com/llvm/llvm-project/pull/66825