[GHC] #11568: Regression in nofib/shootout/k-nucleotide

[GHC]

#11568: Regression in nofib/shootout/k-nucleotide
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        Reporter:  simonmar          |                Owner:  dfeuer
            Type:  bug               |               Status:  new
        Priority:  high              |            Milestone:  8.2.1
       Component:  Compiler          |              Version:  7.10.3
      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 dfeuer):

 According to ticky-ticky profiling, the big things being allocated
 (`alloc'd`) after the patch that caused the regression are `$j1` and `$j2`
 in `$s$wfoldMe`. Neither of these showed up in ticky-ticky before. I think
 `$j2` may be new after the patch, but `$j1` was there before; perhaps it
 was LNEed before and isn't now? I'll try to dig deeper on Sunday.

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11568#comment:4>
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