[GHC] #9476: Implement late lambda-lifting

[GHC]

#9476: Implement late lambda-lifting
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        Reporter:  simonpj           |                Owner:  nfrisby
            Type:  feature request   |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  7.8.2
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Runtime           |  Unknown/Multiple
  performance bug                    |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #8763             |  Differential Rev(s):
       Wiki Page:  LateLamLift       |
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Comment (by simonpj):

 > A late demand analysis run would probably detect the same.

 -O2 does late demand analysis for this very reason.  So presumably it
 doesn't catch it.

 >  "It's not enough to look at Core alone to gauge allocation"

 I agree that STG has a stronger operational model than Core.  (Core is not
 bad, but STG is better.)  But that's an ''advantage'' of doing LLF in STG,
 not a ''disadvantage''.

 Do have a go!

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9476#comment:18>
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