[PATCH] D47681: [DAGCombiner] Bug 31275- Extract a shift from a constant mul or udiv if a rotate can be formed

[Roman Lebedev via Phabricator via llvm-commits]

lebedev.ri added a comment.

In https://reviews.llvm.org/D47681#1131982, @sameconrad wrote:

> In https://reviews.llvm.org/D47681#1131359, @lebedev.ri wrote:
>
> > BTW, that reminds me.
> >  @sameconrad while you are looking at rotates in backend, can you please also check (at least add tests,
> >  if there aren't any yet) that backend properly handles the cases where `mul`/`div` were transformed into shifts?
>
>
>
>
> > I can take a look at that, will do that in a separate patch.
>
> Actually nvm, I see what you're saying.  I'll try to update this patch in a bit for that case.


You can refer to the tests in https://reviews.llvm.org/D48229 for the examples of patterns that are related.


https://reviews.llvm.org/D47681