[llvm-branch-commits] [llvm] release/23.x: [ARM][MVE] Match canonical saturating negation patterns (#213085) (PR #213699)

[David Green via llvm-branch-commits]

davemgreen wrote:

Hello. This does fix a performance regression from #194519 where the canonical form of the instructions has changed, leading to backend no longer matching the existing instructions.

Luckily the new patterns are relatively simple and should be safe for the branch. In that regard this LGTM, it is up to the release maintainer whether they are willing to accept the patch on the branch at this point.

https://github.com/llvm/llvm-project/pull/213699