[GHC] #5113: Huge performance regression of 7.0.2, 7.0.3 and HEAD over 7.0.1 and 6.12 (MonoLocalBinds)

[GHC]

#5113: Huge performance regression of 7.0.2, 7.0.3 and HEAD over 7.0.1 and 6.12
(MonoLocalBinds)
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        Reporter:                    |                   Owner:
  daniel.is.fischer                  |                  Status:  closed
            Type:  bug               |               Milestone:
        Priority:  normal            |                 Version:  7.0.3
       Component:  Compiler          |                Keywords:
      Resolution:  fixed             |  performance, MonoLocalBinds
Operating System:  Linux             |            Architecture:  x86
 Type of failure:  Runtime           |               Test Case:
  performance bug                    |  perf/should_run/T5113
      Blocked By:                    |                Blocking:
 Related Tickets:                    |  Differential Revisions:
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Comment (by bgamari):

 The above bindings are introduced during FloatOut in both the good and bad
 cases, as expected. The cases diverge in the very next pass (`SimplMode
 {Phase = 2 [main], inline, rules, eta-expand, case-of-case}`) where they
 are inlined in the good case but not in the bad. This of course isn't
 terribly surprising but I thought I'd write it down anyways.

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/5113#comment:8>
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