[GHC] #14980: Runtime performance regression with binary operations on vectors

[GHC]

#14980: Runtime performance regression with binary operations on vectors
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        Reporter:  ttylec            |                Owner:  bgamari
            Type:  bug               |               Status:  new
        Priority:  high              |            Milestone:  8.8.1
       Component:  Compiler          |              Version:  8.2.2
      Resolution:                    |             Keywords:  vector
                                     |  bitwise operations
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 tdammers):

 Performed an evil experiment: I put the `cabal.config` from LTS-11.1 into
 the project, then compiled with cabal, forcing the compiler to 8.0.2.
 Behavior is "good" (i.e., the 4th benchmark is in the 20-40 μs range. I
 also get the "good" behavior when compiling with 8.0.2, but without
 pinning.

 So it's definitely not the libraries.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14980#comment:21>
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