[PATCH] D61263: [X86][SSE] Fold scalar horizontal add/sub for non-0/1 element extractions

[Simon Pilgrim via Phabricator via llvm-commits]

RKSimon added inline comments.


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Comment at: test/CodeGen/X86/haddsub.ll:1012
 ; AVX-NEXT:    vpermilps {{.*#+}} xmm0 = xmm0[3,1,2,3]
 ; AVX-NEXT:    vaddss %xmm0, %xmm1, %xmm0
 ; AVX-NEXT:    vzeroupper
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We still miss folding to extractf128+hadd+permilps - but the cost-benefit isn't great.


Repository:
  rL LLVM

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D61263/new/

https://reviews.llvm.org/D61263