[clang] [llvm] Match bitsin(typeof(x)) - popcnt(x) to s_bcnt0_i32 on AMDGPU (PR #164847)

[Matt Arsenault via llvm-commits]

https://github.com/arsenm requested changes to this pull request.

This should not introduce a builtin or intrinsic. This can be purely done in tablegen patterns without the intermediate step 

https://github.com/llvm/llvm-project/pull/164847