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[SCEV] Add transform zext((A * B * ...)<nuw>) --> (zext(A) * zext(B) * ...)<nuw>.
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Authored by jlebar on Jun 11 2018, 11:29 AM.

Event Timeline

jlebar created this revision.Jun 11 2018, 11:29 AM
sanjoy accepted this revision.Jun 11 2018, 11:58 AM

lgtm

This revision is now accepted and ready to land.Jun 11 2018, 11:58 AM
This revision was automatically updated to reflect the committed changes.

Hi Justin,

This (or the previous) commit caused a ~1.4% compile time slowdown on CTMark/mafft/pairlocalalign. Any ideas on how we can avoid it?
I don’t have more details at the moment, but I’d be happy to dig deeper if that helps.

Thanks,
Michael

Hi Justin,

This (or the previous) commit caused a ~1.4% compile time slowdown on CTMark/mafft/pairlocalalign. Any ideas on how we can avoid it?

Is there some way to figure out what exactly got slower (it could be SCEV or some user of SCEV)?

Is there some way to figure out what exactly got slower (it could be SCEV or some user of SCEV)?

Not really at the moment.

I'm trying to locally reproduce it, and maybe I'll get more insight into it later. So far it's been reported by several internal bots testing different opt-levels, so it doesn't look to be just a noise.

Michael