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[TTI][AArch64][SLP] Sets the cost of an ADD reduction 2xi64 to 2.
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Authored by vporpo on Jul 28 2022, 5:59 PM.

Details

Summary

2xi64 is the legalized type for wide reductions (like 16xi64) and setting the
cost to 2 makes load-reduce and load-zext-reduce patterns profitable.

The few performance measurments that I did on an aarch64 machine confirm that
these patterns are actually faster when vectorized.

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Event Timeline

vporpo created this revision.Jul 28 2022, 5:59 PM
Herald added a project: Restricted Project. · View Herald TranscriptJul 28 2022, 5:59 PM
vporpo requested review of this revision.Jul 28 2022, 5:59 PM
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dmgreen accepted this revision.Jul 30 2022, 9:37 AM

I agree, 2 sounds OK to me.
LGTM

This revision is now accepted and ready to land.Jul 30 2022, 9:37 AM
This revision was landed with ongoing or failed builds.Aug 1 2022, 1:04 PM
This revision was automatically updated to reflect the committed changes.