[GHC] #12626: Remove redundant type applications in Core

[GHC]

#12626: Remove redundant type applications in Core
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        Reporter:  nomeata           |                Owner:
            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):

 Proof of concept in branch `wip/T12626`. It builds, and the resulting ghc2
 runs. Test suite does not go through yet, so it might not be bug free, but
 I think the code explains the idea. Better to look at the commits
 individually, as one commit moves `exprType` to `coreSyn`, which is of
 course not essential to understanding the idea here.

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12626#comment:3>
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