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[TargetLowering] Improve expansion of ROTL/ROTR
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Authored by foad on Jun 25 2020, 3:57 AM.

Details

Summary

Using a negation instead of a subtraction from a constant can save an
instruction on some targets.

Nothing much uses this until D77152 changes the translation of fshl and
fshr intrinsics.

Diff Detail

Event Timeline

foad created this revision.Jun 25 2020, 3:57 AM
Herald added a project: Restricted Project. · View Herald TranscriptJun 25 2020, 3:57 AM
arsenm accepted this revision.Jul 3 2020, 10:30 AM
This revision is now accepted and ready to land.Jul 3 2020, 10:30 AM
This revision was automatically updated to reflect the committed changes.