Nested CPR patch review

[Matthew Pickering]

Would one of you have time to review this patch now?

Is there something more needed?

Matt

On Sun, Jan 7, 2018 at 10:11 AM, Sebastian Graf <sgraf1337 at gmail.com> wrote:
> I've since run NoFib. You can find the results here:
> https://phabricator.haskell.org/D4244#119697
>
> I wonder if you feel that any more notes are needed? The general idea of CPR
> remained the same, it's just the extension of the DmdResult lattice that
> needs some rationale as to why and when these new values are needed.
>
> I also wonder what the impact of "Slightly strengthen the strictness
> analysis"
> (https://ghc.haskell.org/trac/ghc/wiki/NestedCPR/Akio2017#Changestothedemandanalyzer)
> would be if regarded in isolation.
>
> On Tue, Jan 2, 2018 at 11:52 AM, Matthew Pickering
> <matthewtpickering at gmail.com> wrote:
>>
>> I don't think anyone has run nofib on the rebased branch yet.
>>
>> The Akio2017 subpage is a more accurate summary. Sebastian has also
>> been adding notes to explain the more intricate parts.
>>
>> Matt
>>
>> On Fri, Dec 22, 2017 at 5:27 PM, Simon Peyton Jones
>> <simonpj at microsoft.com> wrote:
>> > Terrific!
>> >
>> > What are the nofib results?
>> >
>> > Can we have a couple of artificial benchmarks in cpranal/should_run that
>> > show substantial perf improvements because the nested CPR wins in some inner
>> > loop?
>> >
>> > Is https://ghc.haskell.org/trac/ghc/wiki/NestedCPR still an accurate
>> > summary of the idea?   And the Akio2017 sub-page?  It would be easier to
>> > review the code if the design documentation accurately described it.
>> >
>> > I'll look in the new year.  Thanks!
>> >
>> > Simon
>> >
>> > |  -----Original Message-----
>> > |  From: Matthew Pickering [mailto:matthewtpickering at gmail.com]
>> > |  Sent: 22 December 2017 17:09
>> > |  To: GHC developers <ghc-devs at haskell.org>; Simon Peyton Jones
>> > |  <simonpj at microsoft.com>; Joachim Breitner <mail at joachim-breitner.de>;
>> > |  tkn.akio at gmail.com; Sebastian Graf <sgraf1337 at gmail.com>
>> > |  Subject: Nested CPR patch review
>> > |
>> > |  Hi all,
>> > |
>> > |  I recently resurrected akio's nested cpr branch and put it on
>> > phabricator
>> > |  for review.
>> > |
>> > |  https://phabricator.haskell.org/D4244
>> > |
>> > |  Sebastian has kindly been going over it and ironed out a few kinks in
>> > the
>> > |  last few days. He says now that he believes the patch is correct.
>> > |
>> > |  Is there anything else which needs to be done before merging this
>> > patch?
>> > |
>> > |  Simon, would you perhaps be able to give the patch a look over?
>> > |
>> > |  Cheers,
>> > |
>> > |  Matt
>
>