[GHC] #12618: Add saturated constructor applications to Core

[GHC]

#12618: Add saturated constructor applications to Core
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        Reporter:  simonpj           |                Owner:  nomeata
            Type:  feature request   |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.0.1
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by nomeata):

 Small update: I have a branch implementing non-compressing `ConApp` that
 validates and with no significant effect on the program runtimes. And
 already now, two perf test cases (#9961 and #9233) improved! So there
 might be something in here for us.

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12618#comment:30>
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