[llvm] [AMDGPU] Implement Waitcnt Expansion for Profiling (PR #169345)

[Pankaj Dwivedi via llvm-commits]

PankajDwivedi-25 wrote:

> > Memory operations to different address can complete in any order, even if the waitcnt is decremented in a fixed order. I'm not sure of how useful this is in practice.
> 
> "the waitcnt is decremented in a fixed order" is all you need: that allows you to associate each s_waitcnt instruction with a corresponding load instruction (at least in straight line code). I can see how that would be useful for profiling.

Thank you so much for the hint, I am still going through details. Let me see how I can address this.

https://github.com/llvm/llvm-project/pull/169345