[GHC] #9646: Simplifer non-determinism leading to 8 fold difference in run time performance

[GHC]

#9646: Simplifer non-determinism leading to 8 fold difference in run time
performance
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              Reporter:  erikd       |            Owner:
                  Type:  bug         |           Status:  closed
              Priority:  normal      |        Milestone:  7.10.1
             Component:  Compiler    |          Version:  7.8.3
            Resolution:  fixed       |         Keywords:
      Operating System:  Linux       |     Architecture:  x86_64 (amd64)
       Type of failure:  Runtime     |       Difficulty:  Unknown
  performance bug                    |       Blocked By:
             Test Case:              |  Related Tickets:
              Blocking:              |
Differential Revisions:              |
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Comment (by jstolarek):

 It would be great if we could have a test for this so we're sure this does
 not regress again. I looked at the repo and the code to reproduce this is
 pretty big. I wonder if it could be reduced further to include it in the
 testsuite.

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9646#comment:14>
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