[llvm] [AMDGPU] Introduce Next-Use Analysis for SSA-based Register Allocation (PR #156079)

[via llvm-commits]

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

Please hold off on landing this PR as we are looking at an alternative solution to cover this one and https://github.com/llvm/llvm-project/pull/171520.

https://github.com/llvm/llvm-project/pull/156079