[GHC] #13339: Arbitrarily large expressions built out of cheap primops are not floated out

[GHC]

#13339: Arbitrarily large expressions built out of cheap primops are not floated
out
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        Reporter:  rwbarton          |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.1
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Runtime           |  Unknown/Multiple
  performance bug                    |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by simonpj):

 Yes, taking the size into account would be good.  Floating this this out
 requires boxing it, and doing an eval/unbox inside the loop.  When is that
 cheaper than a dozen in-register additions?  I'm not sure.

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13339#comment:4>
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