Re: [GHC] #14240: CSE’ing w/w’ed code regresses program runtime

[GHC]

#14240: CSE’ing w/w’ed code regresses program runtime
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        Reporter:  nomeata           |                Owner:  nomeata
            Type:  bug               |               Status:  closed
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.2.1
      Resolution:  invalid           |             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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Changes (by nomeata):

 * status:  new => closed
 * resolution:   => invalid


Comment:

 changeset:28a115e/ghc “fixed” the `lambda` regression. I conclude that
 this is a layout issue…

 I really wish we could get a better handle on these things. Whenever the
 RTS is touched, even by completely minuscule changes, a few benchmarks go
 up or down by 3 to 5 runtime.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14240#comment:3>
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