[GHC] #10400: Run time increases by 40% in fractal plotter core loop

[GHC]

#10400: Run time increases by 40% in fractal plotter core loop
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        Reporter:  saffroy           |                   Owner:
            Type:  bug               |                  Status:  new
        Priority:  normal            |               Milestone:
       Component:  Compiler          |                 Version:  7.8.4
      Resolution:                    |                Keywords:
Operating System:  Linux             |            Architecture:  x86_64
 Type of failure:  Runtime           |  (amd64)
  performance bug                    |               Test Case:
      Blocked By:                    |                Blocking:
 Related Tickets:                    |  Differential Revisions:
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Comment (by saffroy):

 Ah! Indeed, with `-fllvm` the run times are much more consistent across
 versions of GHC.
 || version || run time (sec) - bangs || no bangs ||
 ||7.4.2 || 4.99|| 19.67||
 ||7.6.3 || 4.99|| 19.30||
 ||7.8.4 || 4.80|| 4.80||
 ||7.10.1 || 4.97|| 4.97||

 In this case, do we keep this bug open?

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10400#comment:4>
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