[GHC] #11597: Optimize cmpTypeX

[GHC]

#11597: Optimize cmpTypeX
-------------------------------------+-------------------------------------
        Reporter:  goldfire          |                Owner:  goldfire
            Type:  task              |               Status:  new
        Priority:  highest           |            Milestone:  8.0.1
       Component:  Compiler          |              Version:  7.10.3
      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:                    |
-------------------------------------+-------------------------------------

Comment (by Ben Gamari <ben@…>):

 In [changeset:"073e20ebda73309173b6b6e3ea10164e8808cc79/ghc" 073e20e/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="073e20ebda73309173b6b6e3ea10164e8808cc79"
 cmpTypeX: Avoid kind comparison when possible

 This comparison is only necessary when the types being compared contain
 casts. Otherwise the structural equality of the types implies that their
 kinds are equal.

 Test Plan: Validate

 Reviewers: goldfire, austin, simonpj

 Reviewed By: simonpj

 Subscribers: thomie

 Differential Revision: https://phabricator.haskell.org/D1944

 GHC Trac Issues: #11597
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11597#comment:2>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler