[GHC] #8793: Improve GHC.Event.IntTable performance

[GHC]

#8793: Improve GHC.Event.IntTable performance
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        Reporter:  cdk               |                Owner:
            Type:  task              |               Status:  patch
        Priority:  normal            |            Milestone:  8.0.1
       Component:  Core Libraries    |              Version:  7.6.3
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Runtime           |  Unknown/Multiple
  performance bug                    |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by simonpj):

 * Do we have any (reproducible) evidence showing that this change makes
 things go faster?  Perhaps a benchmark test of the relevant functions
 themselves?  That would be helpful.  Once we have that evidence, we can go
 ahead and commit.

 * Secondly, are the changes something that a reasonable person might
 expect the optimiser should be able to do by itself?  If so, why doesn't
 it?  Let's not close the ticket until we know about this.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8793#comment:12>
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