Re: [GHC] #9537: concatMap is not a good producer for list fusion

21 Oct 2014

      #9537: concatMap is not a good producer for list fusion
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              Reporter:  dfeuer      |            Owner:  ekmett
                  Type:  bug         |           Status:  patch
              Priority:  normal      |        Milestone:  7.10.1
             Component:  Core        |          Version:  7.9
  Libraries                          |         Keywords:  fusion
            Resolution:              |     Architecture:  Unknown/Multiple
      Operating System:              |       Difficulty:  Unknown
  Unknown/Multiple                   |       Blocked By:
       Type of failure:  Runtime     |  Related Tickets:
  performance bug                    |
             Test Case:              |
              Blocking:              |
Differential Revisions:  Phab:D348   |
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Comment (by Austin Seipp ):

 In [changeset:"1e269bf404fb2719bbe8d72154156ef275c9a6f9/ghc"]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="1e269bf404fb2719bbe8d72154156ef275c9a6f9"
 Make Data.List.concatMap fuse better

 Summary:
 Fix #9537 precisely as Joachim Breitner proposed in
 http://www.haskell.org/pipermail/haskell-cafe/2011-December/097228.html

 Reviewers: austin, nomeata

 Reviewed By: austin, nomeata

 Subscribers: thomie, carter, ezyang, simonmar

 Differential Revision: https://phabricator.haskell.org/D348

 GHC Trac Issues: #9537
 }}}

--
Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/9537#comment:4
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