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[NewPM] Introduce (GPU)DivergenceAnalysis in the new pass manager
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Authored by sameerds on Feb 12 2021, 9:36 AM.

Details

Summary

The GPUDivergenceAnalysis is now renamed to just "DivergenceAnalysis"
since there is no conflict with LegacyDivergenceAnalysis. In the
legacy PM, this analysis can only be used through the legacy DA
serving as a wrapper. It is now made available as a pass in the new
PM, and has no relation with the legacy DA.

The new DA currently cannot handle irreducible control flow; its
presence can cause the analysis to run indefinitely. The analysis is
now modified to detect this and report all instructions in the
function as divergent. This is super conservative, but allows the
analysis to be used without hanging the compiler.

Diff Detail

Event Timeline

sameerds created this revision.Feb 12 2021, 9:36 AM
sameerds requested review of this revision.Feb 12 2021, 9:36 AM
Herald added a project: Restricted Project. · View Herald TranscriptFeb 12 2021, 9:36 AM
aeubanks accepted this revision.Feb 12 2021, 12:41 PM

lgtm, thanks for doing this!

This revision is now accepted and ready to land.Feb 12 2021, 12:41 PM

lgtm, thanks for doing this!

Thanks, that was fast! I'll wait a couple of days to see if @simoll has any comments about the changes to the analysis implementation itself.

This revision was landed with ongoing or failed builds.Feb 15 2021, 8:57 PM
This revision was automatically updated to reflect the committed changes.