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

[GHC]

#14980: Runtime performance regression with binary operations on vectors
-------------------------------------+-------------------------------------
        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:                    |
-------------------------------------+-------------------------------------

Comment (by tdammers):

 Replying to [comment:13 simonpj]:
 > If the badness is only for a particular stack LTS, I wonder if the
 badness will go away in the next stack LTS and we can declare this ticket
 moot?

 That would of course be a "beautiful" solution. I could try pinning it
 down to a specific library, and force that to the newest version in the
 LTS 11.1 build, see if that makes any difference.

 Another thing to try would be to create a `cabal.config` with the exact
 library versions that stack uses; if that reproduces the badness, then
 it's the libraries, but if it doesn't, then the most likely explanation is
 that cabal does something wrong.

 Yet another thing would be to set up two VMs, each of them having only one
 GHC toolchain installed, one for 8.0.2 and one for 8.2.2, and see if
 *that* has us reproduce the observed behavior.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14980#comment:15>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler