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[X86] Increase the depth threshold required to form VPERMI2W/VPERMI2B in shuffle combining
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Authored by craig.topper on Sep 29 2020, 10:22 AM.

Details

Summary

These instructions are implemented with two port 5 uops and one port 015 uop so they are more complicated that most shuffles.

This patch increases the depth threshold for when we form them during shuffle combining to try to limit increasing the number of uops especially on port 5.

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Event Timeline

craig.topper created this revision.Sep 29 2020, 10:22 AM
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craig.topper requested review of this revision.Sep 29 2020, 10:22 AM
This revision is now accepted and ready to land.Sep 29 2020, 10:44 AM