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

[Roman Lebedev via Phabricator via llvm-commits]

lebedev.ri added inline comments.


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Comment at: llvm/test/CodeGen/X86/vector-narrow-binop.ll:112
+; SSE-NEXT:    punpckldq {{.*#+}} xmm2 = xmm2[0],xmm0[0],xmm2[1],xmm0[1]
+; SSE-NEXT:    pand {{\.?LCPI[0-9]+_[0-9]+}}(%rip), %xmm2
+; SSE-NEXT:    psrlq $16, %xmm2
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lebedev.ri wrote:
> This is all-ones mask
Err, no, not all-ones mask. It masks away high half/byte of each i16 element.


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

https://reviews.llvm.org/D140811