[llvm] [SampleFDO] Stale profile renaming matching (PR #92151)

[via llvm-commits]

WenleiHe wrote:

> confirmed 90%+ of the found renaming pair is good. (There could be incorrect renaming pair if the num of the anchor is small, but checked that those functions are simple cold function)

There is no guarantee that these wrong matching can only happen in cold functions. I'm wondering if we should skip name matching attempt for tiny functions where don't have enough signal for high confidence matching. 

https://github.com/llvm/llvm-project/pull/92151