Sounds good to me. Thanks, Geoff, for doing this!
Manuel Austin Seipp <aus...@well-typed.com>: > On Mon, Aug 4, 2014 at 8:49 AM, Geoffrey Mainland <mainl...@apeiron.net> > wrote: >> I have patches for DPH that let it work with vector 0.11 as of a few >> months ago. I would be happy to submit them via phabricator if that is >> agreeable (we have to coordinate with the import of vector 0.11 >> though...I can instead leave them in a wip branch for Austin to merge as >> he sees fit). I am also willing to commit some time to keep DPH at least >> working in its current state. > > That would be quite nice if you could submit patches to get it to > work! Thanks so much. > > As we've moved to submodules, having our own forks is becoming less > palatable; we'd like to start tracking upstream closely, and having > people submit changes there first and foremost. This creates a bit of > a lag time between changes, but I think this is acceptable (and most > of our maintainers are quite responsive to GHC needs!) > > It's also great you're willing to help maintain DPH a bit - but based > on what Ben said, it seems like a significant rewrite will happen > eventually. > > Geoff, here's my proposal: > > 1) I'll disable DPH for right now, so it won't pop up during > ./validate. This will probably happen today. > 2) We can coordinate the update of vector to 0.11, making it track > the official master. (Perhaps an email thread or even Skype would > work) > 3) We can fix DPH at the same time. > 4) Afterwords, we can re-enable it for ./validate > > If you submit Phabricator patches, that would be fantastic - we can > add the DPH repository to Phabricator with little issue. > > In the long run, I think we should sync up with Ben and perhaps Simon > & Co to see what will happen long-term for the DPH libraries. > >> Geoff >> >> On 8/4/14 8:18 AM, Ben Lippmeier wrote: >>> On 4 Aug 2014, at 21:47 , Austin Seipp <aus...@well-typed.com> wrote: >>> >>>> Why? Because I'm afraid I just don't have any more patience for DPH, >>>> I'm tired of fixing it, and it takes up a lot of extra time to build, >>>> and time to maintain. >>> I'm not going to argue against cutting it lose. >>> >>> >>>> So - why are we still building it, exactly? >>> It can be a good stress test for the simplifier, especially the SpecConstr >>> transform. The fact that it takes so long to build is part of the reason >>> it's a good stress test. >>> >>> >>>> [1] And by 'speak up', I mean I'd like to see someone actively step >>>> forward address my concerns above in a decisive manner. With patches. >>> I thought that in the original conversation we agreed that if the DPH code >>> became too much of a burden it was fine to switch it off and let it become >>> unmaintained. I don't have time to maintain it anymore myself. >>> >>> The original DPH project has fractured into a few different research >>> streams, none of which work directly with the implementation in GHC, or >>> with the DPH libraries that are bundled with the GHC build. >>> >>> The short of it is that the array fusion mechanism implemented in DPH >>> (based on stream fusion) is inadequate for the task. A few people are >>> working on replacement fusion systems that aim to solve this problem, but >>> merging this work back into DPH will entail an almost complete rewrite of >>> the backend libraries. If it the existing code has become a maintenance >>> burden then it's fine to switch it off. >>> >>> Sorry for the trouble. >>> Ben. >>> >> > > > > -- > Regards, > > Austin Seipp, Haskell Consultant > Well-Typed LLP, http://www.well-typed.com/
signature.asc
Description: Message signed with OpenPGP using GPGMail
_______________________________________________ ghc-devs mailing list ghc-devs@haskell.org http://www.haskell.org/mailman/listinfo/ghc-devs
