[llvm] [PGO] Sampled instrumentation in PGO to speed up instrumentation binary (PR #69535)

[Matthew Voss via llvm-commits]

ormris wrote:

I'm seeing some buildbot failures after this commit: https://lab.llvm.org/buildbot/#/builders/66/builds/1956

@xur-llvm Could you take a look?

https://github.com/llvm/llvm-project/pull/69535