[llvm] [AMDGPU] Handle unset/max flat workgroup size in waves/EU (PR #139955)

[Nikolay Panchenko via llvm-commits]

npanchen wrote:

fyi: I was trying to reduce our test case where all functions have `amdgpu-flat-work-group-size` set with some having 1,1024. However, llvm-reducer 

> I'm gonna put a block here, since this block of code is gonna go anyway after #123995 is merged.

Do you have some ETA of when it's going to land ? Your PR is ~4 months old, while we started to observe assertion due to https://github.com/llvm/llvm-project/pull/137807 that was created and merged within a week.

https://github.com/llvm/llvm-project/pull/139955