[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):

 Split off tasks 1 (the original patch from [comment:5]) and 2 (further
 refactoring of coercionKind/Role) into separate branches, cherry-picking
 commits onto current GHC HEAD.

 Branches are `wip/tdammers/T11735-1` and `wip/tdammers/T11735-2` (the
 latter also contains commits from the former, because I figured that would
 make more sense).

 I also pushed the patch for task 1 to phabricator
 [https://phabricator.haskell.org/D4355 D4355].

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11735#comment:58>
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