[GHC] #8766: length [Integer] is twice as slow but length [Int] is 10 times faster

[GHC]

#8766: length [Integer] is twice as slow but length [Int] is 10 times faster
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        Reporter:  George                   |            Owner:  nomeata
            Type:  bug                      |           Status:  merge
        Priority:  normal                   |        Milestone:  7.8.1
       Component:  Compiler                 |          Version:  7.8.1-rc1
      Resolution:                           |         Keywords:
Operating System:  Unknown/Multiple         |     Architecture:
 Type of failure:  Runtime performance bug  |  Unknown/Multiple
       Test Case:  T8755                    |       Difficulty:  Unknown
        Blocking:                           |       Blocked By:
                                            |  Related Tickets:
--------------------------------------------+------------------------------
Changes (by nomeata):

 * status:  new => merge
 * testcase:   => T8755


Comment:

 Pushed, please merge to 7.8.

 If you also merge the test case (the first performance test in
 `libraries/base/tests` – I hope there was no good reason why there weren’t
 any before) you probably have to adjust the numbers, unless we also merge
 the call-arity analysis (which I don’t think has seen enough testing to go
 into a stable release).

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8766#comment:12>
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