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[AArch64] Prefer fmov over orr v.16b when copying f32/f64
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Authored by dmgreen on Jul 20 2021, 8:06 AM.

Details

Summary

This change the lowering of f32 and f64 COPY from a 128bit vector ORR to a fmov of the appropriate type. At least on some CPU's with 64bit NEON data paths this is expected to be faster, and shouldn't be slower on any CPU that treats fmov as a register rename.

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Event Timeline

dmgreen created this revision.Jul 20 2021, 8:06 AM
dmgreen requested review of this revision.Jul 20 2021, 8:06 AM
Herald added a project: Restricted Project. · View Herald TranscriptJul 20 2021, 8:06 AM
dmgreen updated this revision to Diff 363457.Aug 2 2021, 6:00 AM
dmgreen added reviewers: SjoerdMeijer, NickGuy, efriedma.

Rebase and update the formatting.

SjoerdMeijer accepted this revision.Aug 2 2021, 6:04 AM

Looks reasonable to me. Perhaps wait a day if others want to comment.

This revision is now accepted and ready to land.Aug 2 2021, 6:04 AM
This revision was automatically updated to reflect the committed changes.