[GHC] #9203: Perf regression in 7.8.2 relative to 7.6.3, possibly related to HashMap

[GHC]

#9203: Perf regression in 7.8.2 relative to 7.6.3, possibly related to HashMap
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        Reporter:  simonmar                 |            Owner:
            Type:  bug                      |           Status:  new
        Priority:  high                     |        Milestone:  7.8.3
       Component:  Compiler                 |          Version:  7.8.2
      Resolution:                           |         Keywords:
Operating System:  Unknown/Multiple         |     Architecture:
 Type of failure:  Runtime performance bug  |  Unknown/Multiple
       Test Case:                           |       Difficulty:  Unknown
        Blocking:                           |       Blocked By:
                                            |  Related Tickets:
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Comment (by simonpj):

 Yes, great fix, let's get it in as soon as poss. I've added Phab comment
 thought.

 Simon

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9203#comment:5>
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