[GHC] #12129: Optimize the implementation of minusInteger in the integer-gmp package

[GHC]

#12129: Optimize the implementation of minusInteger in the integer-gmp package
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        Reporter:  admock            |                Owner:  admock
            Type:  task              |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  libraries         |              Version:  8.0.1
  (other)                            |
      Resolution:                    |             Keywords:  integer-gmp
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Runtime           |  Unknown/Multiple
  performance bug                    |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  Phab:D2278
       Wiki Page:                    |
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Comment (by Ben Gamari <ben@…>):

 In [changeset:"02f893eb4fe3f75f0a9dc7e723568f4c75de5785/ghc"
 02f893eb/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="02f893eb4fe3f75f0a9dc7e723568f4c75de5785"
 integer-gmp: Make minusInteger more efficient

 Give `minusInteger` its own implementation.
 Previously `minusInteger` used `plusInteger` and `negateInteger`, which
 meant it always allocated.  Now it works more like `plusInteger`.

 Reviewers: goldfire, hvr, bgamari, austin

 Reviewed By: hvr, bgamari, austin

 Subscribers: thomie

 Differential Revision: https://phabricator.haskell.org/D2278

 GHC Trac Issues: #12129
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12129#comment:3>
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