[GHC] #11735: Optimize coercionKind

[GHC]

#11735: Optimize coercionKind
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        Reporter:  goldfire          |                Owner:  (none)
            Type:  task              |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  7.10.3
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Compile-time      |  Unknown/Multiple
  performance bug                    |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by tdammers):

 Replying to [comment:75 simonpj]:
 > OK: once we have a separate Phab for the `simplCast` change, I'll review
 it.   Ping me, Tobias!

 I split up D4385 into https://phabricator.haskell.org/D4394 (the NthCo
 stuff) and https://phabricator.haskell.org/D4395 (simplCast / Simplify).
 May I assume that the refactoring mentioned in comment:76 should go in
 D4394?

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11735#comment:77>
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