[GHC] #9660: unnecessary indirect jump when returning a case scrutinee

[GHC]

#9660: unnecessary indirect jump when returning a case scrutinee
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              Reporter:  rwbarton    |            Owner:
                  Type:  bug         |           Status:  new
              Priority:  normal      |        Milestone:
             Component:  Compiler    |          Version:  7.8.3
  (CodeGen)                          |         Keywords:
            Resolution:              |     Architecture:  Unknown/Multiple
      Operating System:              |       Difficulty:  Unknown
  Unknown/Multiple                   |       Blocked By:
       Type of failure:  Runtime     |  Related Tickets:
  performance bug                    |
             Test Case:              |
              Blocking:              |
Differential Revisions:              |
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Comment (by simonmar):

 It ought to be a clear win.  To be extra sure I'd compare the sizes of
 object files in nofib built both ways, find some object files that differ,
 and then compare the assembly output for those modules, just to be sure
 that nothing unexpected is happening.

 I'd also double-check any nofib results that appear to vary by more than a
 few percent.  You can use perf to count instructions, which should go
 down.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9660#comment:5>
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