[PATCH] D143787: [X86] Try to use `{v}shufps` instead of `vpermilps` for common float shuffles.

[Noah Goldstein via Phabricator via llvm-commits]

goldstein.w.n added a comment.

In D143787#4122814 <https://reviews.llvm.org/D143787#4122814>, @RKSimon wrote:

> I think this should be controlled by a tuning flag tbh, or even better we do this in a later pass and not in dag/isel

Where would you suggest putting it?

Also what is the case for the seperate tuning flag? AFAICT its just better code size and equal or better perf so seems
like clear universal win.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D143787/new/

https://reviews.llvm.org/D143787