[GHC] #10397: Compiler performance regression 7.6 -> 7.8 in elimCommonBlocks

[GHC]

#10397: Compiler performance regression 7.6 -> 7.8 in elimCommonBlocks
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        Reporter:  TobyGoodwin       |                Owner:  (none)
            Type:  bug               |               Status:  closed
        Priority:  normal            |            Milestone:  7.10.2
       Component:  Compiler          |              Version:  7.8.4
      Resolution:  fixed             |             Keywords:  performance
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:  see ticket
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  Phab:D892
       Wiki Page:                    |  Phab:D896
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Changes (by TobyGoodwin):

 * Attachment "ghc10397.tar" added.

 rwbarton's simple code to reproduce the compiler performance problem

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10397>
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