[PATCH] D52997: [x86] allow single source horizontal op matching (PR39195)

[Douglas Yung via Phabricator via llvm-commits]

dyung added a comment.

In https://reviews.llvm.org/D52997#1258717, @spatel wrote:

> In https://reviews.llvm.org/D52997#1258666, @andreadb wrote:
>
> > I don't see it as a big problem if we start "regressing" this particular case on Jaguar.
>
>
> Ok - that's not the impression I got reading PR39195. @dyung - how important is this pattern?


I will defer to Andrea's expertise in this area. I was under the impression that generating the horizontal add/sub instructions was preferred for these cases (especially for btver2), but if that is not the case, I can update our test to not expect it to be generated.


https://reviews.llvm.org/D52997