[PATCH] D100486: [COST]Improve cost model for shuffles in SLP.

Thu May 5 12:15:57 PDT 2022

ABataev added a comment.

In D100486#3494581 <https://reviews.llvm.org/D100486#3494581>, @asbirlea wrote:

> We currently root-caused a 20% regression in eigen complex to this patch and it is blocking our compiler release.
> I need some time to do additional testing, given there are at least a few patches on top of this. So far I see a crash fix, two NFCs and two additional changes that may also affect performance (https://reviews.llvm.org/D114171 and https://reviews.llvm.org/D115750).
> Can you please hold off on any additional changes while we test further, or include them here for review so I can check if they resolve the regressions seen so far?

Most probably, some overoptimistic cost model estimations turned on some extra vectorization. The reproducer will help, if you can provide it.

Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D100486/new/

https://reviews.llvm.org/D100486