[GHC] #7206: Implement cheap build

[GHC]

#7206: Implement cheap build
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        Reporter:  simonpj           |                Owner:  simonpj
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:  ⊥
       Component:  Compiler          |              Version:  7.4.2
      Resolution:                    |             Keywords:  FloatOut
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Runtime           |  Unknown/Multiple
  performance bug                    |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #8763, #13422     |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by osa1):

 I pushed my branch to `wip/cheap-build-osa1` in GHC's git repo as well.
 Also attached the nofib output.

 As to why `nums` is not inlined in comment:24, I see this in `-ddump-
 inlinings` output:

 {{{
 Considering inlining: nums_aSY
   arg infos []
   interesting continuation RuleArgCtxt
   some_benefit False
   is exp: False
   is work-free: False
   guidance ALWAYS_IF(arity=0,unsat_ok=False,boring_ok=False)
   ANSWER = NO
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/7206#comment:26>
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