[GHC] #9374: Investigate Static Argument Transformation

[GHC]

#9374: Investigate Static Argument Transformation
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        Reporter:  jstolarek         |                Owner:  (none)
            Type:  task              |               Status:  new
        Priority:  lowest            |            Milestone:
       Component:  Compiler          |              Version:  7.9
      Resolution:                    |             Keywords:
                                     |  StaticArgumentTransformation,
                                     |  LateLamLift
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Runtime           |  Unknown/Multiple
  performance bug                    |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  14816             |  Differential Rev(s):
       Wiki Page:                    |
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Changes (by sgraf):

 * related:   => 14816


Comment:

 For anyone working on this who has problems debugging performance
 regressions, #14816 might be worth taking a look at.

 TLDR; The Demand Analyser tries hard to be precise about parameters, but
 gives up early on demands on free variables for analysis performance
 reasons. So, when SAT turns parameters into free variables, there is the
 slight chance that e.g. SATed single-entry thunks are no longer
 identified.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9374#comment:30>
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