Looking for GSoC Mentor

Previous Topic Next Topic
classic Classic list List threaded Threaded
1 message Options
Reply | Threaded
Open this post in threaded view

Looking for GSoC Mentor

Andreas Klebinger
Hello Everyone,
I’m looking for a mentor for a GSoC Project/Proposal.

The whole idea revolves around:
* Getting hot path information from static analysis and user annotations.
* Making sure it’s not destroyed by optimization passes.
* Using it to generate better code where applicable.

See also:
#14672: Make likelihood of branches/conditions available throughout the compiler.
Towards these goals I would like for GSoC:
* Land https://phabricator.haskell.org/D4327 (Branchweights in STG and Cmm)
  + It might be ready before then. But it’s a prerequisite so worth listing here.
* Design and implement a way for users to:
  + Mark hot paths in Haskell code.
  + Push the information through the passes (up to STG) on a best effort basis. STG and beyond is part of the diff above.
  + The current backend already uses this information in some places, so this alone should lead to small but consistent gains.
  + I don’t plan to add additional optimizations unless there is time left at the end.
Where I think I will need help/experience from a mentor is:
* Frontend questions:
  I haven’t looked at GHC’s parser/renamer yet so while
  this is surmountable I expect some questions to arise there.
* Design questions/feedback:
  Things like:
  + How should the user be able to give this information.
  + What should be flag controlled? What always on?
  + Things like compile time/executable speed tradeoffs.
* Potentially the simplifier:
  I’ve looked into it briefly as originally D4327 was aimed at the
  core stage instead of stg.
  There doesn’t seem to be a lot that could
  mess with hot path information/branchweights. But I haven’t worked on
  the simplifier before and it seems like a good place for unexpected
  issues to arise.

* If this involves the proposal process then also guidance there.
For myself:
* I’m studying at TU Vienna (Software & Information Engineering)
  and am close to finishing my undergrad. Located in Austria (UTC+1)
* I have contributed a few small changes to GHC throughout last year.
  See AndreasK on Phab/Trac.
* If you want to know more contact me!

If you are interested in mentoring me or looking for more details feel free
to contact me at [hidden email] or look for AndreasK in #ghc

Best Regards

ghc-devs mailing list
[hidden email]