[GHC] #10371: GHC fails to inline and specialize a function

[GHC]

#10371: GHC fails to inline and specialize a function
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        Reporter:  MikeIzbicki       |                Owner:
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  7.10.1
      Resolution:                    |             Keywords:  Inlining
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Runtime           |  Unknown/Multiple
  performance bug                    |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #8668             |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by nfrisby):

 I haven't been able to reproduce this with GHC 7.10.2. I see ~200 ns
 averages using:

 * GHC 7.10.2
 * subhask-0.1.0.0 or subhask-0.1.0.0 (from Hackage sdist, with relaxed
 build-depends)
 * MonadRandom-0.4, QuickCheck-2.8.1, approximate-0.2.2.2, base-4.8.1.0,
 bloomfilter-2.0.1.0, bytes-0.15.0.1, bytestring-0.10.6.0, cassava-0.4.4.0,
 containers-0.5.6.2, deepseq-1.4.1.1, erf-2.0.0.0, gamma-0.9.0.2, ghc-
 prim-0.4.0.0, hmatrix-0.16.1.5, hyperloglog-0.3.4, lens-4.12.3, monad-
 primitive-0.1, mtl-2.2.1, parallel-3.2.0.6, pipes-4.1.6,
 primitive-0.6.1.0, semigroups-0.16.2.2, template-haskell-2.10.0.0,
 vector-0.10.12.3

 However, I don't know if either of those are the right `subhask` to use.
 MikeIzbicki, do you have the source for the `subhask` that you originally
 observed the regression with?

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10371#comment:5>
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