[GHC] #7994: Make foldl into a good consumer

[GHC]

#7994: Make foldl into a good consumer
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        Reporter:  simonpj           |            Owner:
            Type:  bug               |           Status:  closed
        Priority:  normal            |        Milestone:
       Component:  Compiler          |          Version:  7.6.3
      Resolution:  fixed             |         Keywords:
Operating System:  Unknown/Multiple  |     Architecture:  Unknown/Multiple
 Type of failure:  None/Unknown      |       Difficulty:  Unknown
       Test Case:                    |       Blocked By:
        Blocking:                    |  Related Tickets:
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Comment (by nomeata):

 Updated numbers, now running nofib in slow mode. Now the results look
 slightly better. Guess that is what benchmarking is about: Tweaking the
 tests until the results are what we want them to be:

 Effect of Call Arity (with the original foldl):
 {{{
                         min    mean     max
       Allocations     -1.3%   -0.0%    0.0%
       Runtime         -4.0%   -0.0%   +4.9%
 }}}
 Effect of Call Arity + defining foldl with foldr:
 {{{
                          min    mean     max
       Allocations     -79.0%   -5.2%    0.0%
       Runtime         -47.4%   -1.9%   +3.0%
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/7994#comment:21>
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