[llvm] [AMDGPU] Convert ds_bpermute/wave_shuffle XOR patterns to DPP row_xmask and permlanex16 (PR #194565)

[Jay Foad via llvm-commits]

jayfoad wrote:

Do we really want to be implementing these optimizations twice, once for bpermute and once for wave_shuffle? Maybe we should canonicalize bpermute to the corresponding wave_shuffle?

https://github.com/llvm/llvm-project/pull/194565