[PATCH] D39292: [X86][AVX512] Adding new patterns for extract_subvector of vXi1

[michael zuckerman via Phabricator via llvm-commits]

m_zuckerman added inline comments.


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Comment at: lib/Target/X86/X86InstrAVX512.td:2981
                    VK2))>;
 def : Pat<(v4i1 (extract_subvector (v8i1 VK8:$src), (iPTR 4))),
           (v4i1 (COPY_TO_REGCLASS
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craig.topper wrote:
> How is this different than line 2965?
The difference here is the type of the instruction word vs byte. Byte, as you said, needs DQ while word doesn't need it. The second pattern will be caught If a target doesn't  have DQ.


https://reviews.llvm.org/D39292