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[ARM] Revert WhileLoopStartLR to DoLoopStart
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Authored by dmgreen on Mar 11 2021, 4:30 AM.

Details

Summary

If a WhileLoopStartLR is reverted due to calls in the preheader, we may still be able to instead create a DoLoopStart, preserving the low overhead loop. This adds code for that, only reverting the WhileLoopStartR to a Br/Cmp, leaving the rest of the low overhead loop in place.

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Event Timeline

dmgreen created this revision.Mar 11 2021, 4:30 AM
dmgreen requested review of this revision.Mar 11 2021, 4:30 AM
Herald added a project: Restricted Project. · View Herald TranscriptMar 11 2021, 4:30 AM
samtebbs accepted this revision.Mar 25 2021, 7:27 AM

Nice idea. LGTM

This revision is now accepted and ready to land.Mar 25 2021, 7:27 AM

Thanks. I had forgotten about this one, which is a bit of a bad sign.

This revision was landed with ongoing or failed builds.Mar 25 2021, 9:44 AM
This revision was automatically updated to reflect the committed changes.