[llvm] [HWASAN] Implement selective instrumentation based on profiling information (PR #83503)

[via llvm-commits]

Enna1 wrote:

Hi @kstoimenov @vitalybuka 

I have some high level questions:
1. What is the motivation of profile information based selective instrumentation? is it about code size?
2. Will the profile information based selective instrumentation be implemented for other sanitizers(asan, msan, tsan)?
3. Will the profile information based selective instrumentation cause some false negatives or false positives?
IIUR, lets say the compilation unit where the heap-buffer-overflow happens is not instrumented, then there is no hwasan check is inserted, so false negative may happen?

Thanks!

https://github.com/llvm/llvm-project/pull/83503