[GHC] #7258: Compiling DynFlags is jolly slow

[GHC]

#7258: Compiling DynFlags is jolly slow
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        Reporter:  simonpj           |                Owner:  simonpj
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  7.6.1
      Resolution:                    |             Keywords:  deriving-perf
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Compile-time      |  Unknown/Multiple
  performance bug                    |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by Ben Gamari <ben@…>):

 In [changeset:"2a4c24e40462832a4a97cd7a65119542e842de81/ghc"
 2a4c24e4/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="2a4c24e40462832a4a97cd7a65119542e842de81"
 Make layLeft and reduceDoc stricter (#7258)

 Making the pretty-printer based assembly output stricter in
 strategically chosen locations produces a minor performance improvement
 when compiling large derived Read instance (on the order of 5-10%).

 Reviewers: austin, bgamari

 Reviewed By: bgamari

 Subscribers: rwbarton, thomie

 Differential Revision: https://phabricator.haskell.org/D4111
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/7258#comment:54>
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