[GHC] #13570: CoreFVs patch makes n-body slower

[GHC]

#13570: CoreFVs patch makes n-body slower
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        Reporter:  simonpj           |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.0.1
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #13629            |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by kavon):

 Well, at least the assembly code after the patch for #13629 is much more
 efficient!

 The sqrt inefficiency in #13629 was a somewhat separate observation: I
 expected nbody to improve a bit because of that fix, counteracting
 whatever weird thing is going on in this regression.

 I guess once the Gipeda report is up we'll see if that patch helped any of
 the benchmarks.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13570#comment:12>
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