[GHC] #8832: Constant-folding regression wrt `clearBit (bit 0) 0 `

[GHC]

#8832: Constant-folding regression wrt `clearBit (bit 0) 0 `
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        Reporter:  hvr                      |            Owner:  simonpj
            Type:  bug                      |           Status:  new
        Priority:  normal                   |        Milestone:  7.8.1
       Component:  Compiler                 |          Version:  7.8.1-rc2
      Resolution:                           |         Keywords:
Operating System:  Unknown/Multiple         |     Architecture:
 Type of failure:  Runtime performance bug  |  Unknown/Multiple
       Test Case:                           |       Difficulty:  Unknown
        Blocking:                           |       Blocked By:
                                            |  Related Tickets:
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Comment (by Simon Peyton Jones <simonpj@…>):

 In [changeset:"ea6dcef1d9800953b1791304d52884359f415ad9/ghc"]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="ea6dcef1d9800953b1791304d52884359f415ad9"
 Test Trac #8832

 The test is a bit crude; -ddump-simpl | grep '#'.

 I'm concerned that the -ddump-simpl output may differ on 32 and 64-bit
 platforms.  So far I've only put in output for 64-bit platforms.
 }}}

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8832#comment:5>
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