[PATCH] D140811: [DAGCombiner][X86] `visitVECTOR_SHUFFLE()`: splats with a single non-undef element are not splats

Tue Jan 3 08:03:00 PST 2023

RKSimon added a comment.

Sorry for the delay - I'm slowly returning from Christmas break.

I think if we can address the horizontal-op regressions then the other cases are pretty trivial to address - tweaking canonicalizeShuffleMaskWithHorizOp might help us.

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Comment at: llvm/test/CodeGen/X86/haddsub-3.ll:7
 ; RUN: llc < %s -mtriple=x86_64-unknown -mattr=+avx,fast-hops   | FileCheck %s --check-prefixes=AVX1,AVX1-FAST
 ; RUN: llc < %s -mtriple=x86_64-unknown -mattr=+avx2            | FileCheck %s --check-prefix=AVX2

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(trivial) Looks like you can add back the baseline common AVX prefix to cover both AVX1/AVX2 checks

Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D140811/new/

https://reviews.llvm.org/D140811