[llvm] [InstrProf] Do not block functions from PGOUse (PR #71106)

[David Li via llvm-commits]

david-xl wrote:

> > I think we should move the size/compiletime related logics outside of skipPGO. There is no point annotate PGO (and waste compile time) when instrumentation is skipped.
> 
> If **instrumentation** is skipped then we should block PGOGen. But if a function is in a profile, we should still run PGOUse on that function and this would not waste compile time, even if it happens to have the `noprofile` attribute for whatever reason.

right. What I meant is to introduce two helper functions:

bool skipPGO() {
    // critical edge based ...
   ..
}

bool skipPGOInstr() {
     if (skipPGO()) 
          return true;
     // attribute based.
    ...
}

https://github.com/llvm/llvm-project/pull/71106