[GHC] #14372: CMM contains a bunch of tail-merging opportunities

[GHC]

#14372: CMM contains a bunch of tail-merging opportunities
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        Reporter:  heisenbug         |                Owner:  (none)
            Type:  feature request   |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.2.1
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by heisenbug):

 Replying to [comment:7 heisenbug]:
 > `-fcmm-elim-common-blocks` helps a bit, but many equal ones are not
 caught:
 >

 Turns out c-b-e is a local optimisation, i.e. per procedure. We need a
 global one to crack this.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14372#comment:8>
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