[GHC] #13825: Allow multiple constructor fields occupy the same word

[GHC]

#13825: Allow multiple constructor fields occupy the same word
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        Reporter:  michalt           |                Owner:  michalt
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:  8.4.1
       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:  #605              |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by Ben Gamari <ben@…>):

 In [changeset:"5469ac86f9cc9e83b93ed34ca13f0a4f58f4a9a6/ghc"
 5469ac86/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="5469ac86f9cc9e83b93ed34ca13f0a4f58f4a9a6"
 Interpreter.c: use macros to access/modify Sp

 This is another step in fixing #13825 (based on D38 by Simon Marlow).

 This commit adds a few macros for accessing and modifying `Sp`
 (interpreter stack) and will be useful to allow sub-word
 indexing/pushing. (but that will be a separate change, this commit
 should introduce no changes in behavior)

 Signed-off-by: Michal Terepeta <michal.terepeta at gmail.com>

 Test Plan: ./validate

 Reviewers: bgamari, simonmar, austin, erikd

 Reviewed By: bgamari, erikd

 Subscribers: rwbarton, thomie

 GHC Trac Issues: #13825

 Differential Revision: https://phabricator.haskell.org/D3744
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13825#comment:8>
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