[GHC] #8763: forM_ [1..N] does not get fused (10 times slower than go function)

[GHC]

#8763: forM_ [1..N] does not get fused (10 times slower than go function)
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        Reporter:  nh2               |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:  8.6.1
       Component:  Compiler          |              Version:  7.6.3
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Runtime           |  Unknown/Multiple
  performance bug                    |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #7206             |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by simonpj):

 > I'll give it a try. Without understanding all operational consequences
 of LLF, I'd still guess that making sure all cs inline would be more
 beneficial in this scenario.

 In general inlining is good.  But in the case on this thread, I think it's
 the non-allocation of a function closure that saves all the work, rather
 than any optimisations that happen after inlining c.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8763#comment:63>
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