[llvm] [AArch64] Convert UADDV(add(zext, zext)) into UADDLV(concat). (PR #78301)

[David Green via llvm-commits]

https://github.com/davemgreen approved this pull request.

Thanks for the updates. I think this LGTM with a couple of extra comments.

https://github.com/llvm/llvm-project/pull/78301