[PATCH] D142288: [X86] Add basic vector handling for ISD::ABDS/ABDU (absolute difference) nodes

Sun Jan 29 06:34:35 PST 2023

RKSimon added a comment.

In D142288#4088725 <https://reviews.llvm.org/D142288#4088725>, @dmgreen wrote:

> The DAG combiner changes LGTM.
>
> I would like to get D119075 <https://reviews.llvm.org/D119075> done in one way or another. It requires creating node for types that are not legal though. I don't think this should prevent that though.

Thanks @dmgreen - I did start looking at ABDS/ABDU legalization but didn't get very far - the ABS(SUB_NSW(X,Y)) pattern in particular is difficult to legalize without instruction bloat - I did wonder about adding NSW flags to the folded ABDS node?

Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D142288/new/

https://reviews.llvm.org/D142288