[llvm] [AMDGPU] Skip register uses in AMDGPUResourceUsageAnalysis (PR #133242)

[Sebastian Neubauer via llvm-commits]

Flakebi wrote:

Thanks for the refactoring!

The tests I quoted above test specific corner cases, I find it much easier to look at and verify a 2 line test than a 20 line test.
The last test of the three I wrote fails with the new version of this change. It emits `.vgpr_count: 0` even though `v0` is live and defined as it’s initialized by the hardware (`v2` is never written in the shader).
I’d still like it if we can have the tests in llvm :)

https://github.com/llvm/llvm-project/pull/133242