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[WIP][TLI] SimplifyDemandedVectorElts(): for `OR`, don't demand elements that are known to be all-ones in another operand
AbandonedPublic

Authored by lebedev.ri on Sep 16 2021, 2:28 PM.

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Reviewers
RKSimon
Summary

This is a suggestion from https://reviews.llvm.org/D109726#3004107, although it does not work.

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lebedev.ri created this revision.Sep 16 2021, 2:28 PM
lebedev.ri requested review of this revision.Sep 16 2021, 2:28 PM
Herald added a project: Restricted Project. · View Herald TranscriptSep 16 2021, 2:28 PM

@RKSimon i don't believe we can emulate what D109726 does when only looking at the OR,
i think we need to actually look at a blend (i.e. look past and and andn of operands),
and know what is being selected from what.

Abandon this?

lebedev.ri abandoned this revision.Dec 13 2021, 6:50 AM