[PATCH] D88569: [DAGCombiner] Call SimplifyDemandedBits to simplify EXTRACT_VECTOR_ELT

Mon Jun 20 07:57:53 PDT 2022

foad added a comment.

In D88569#3594683 <https://reviews.llvm.org/D88569#3594683>, @RKSimon wrote:

> @foad Are you intending to take another look at this at all? I'm wondering if could help with some of the regressions in D127115 <https://reviews.llvm.org/D127115>

TBH I had rather gone off this patch, because it seemed like it would interfere with tests where we want to recombine a bunch of extracts back into some kind of permute instruction. (If you see a bunch of extracts from the same source then you might try to do this, but if one of the extracts has been folded to a constant then it's much harder to spot.) But I have rebased it anyway.

Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D88569/new/

https://reviews.llvm.org/D88569