[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:"dac4b9d3cdca83c99d5d894d2743cc0bbca450ac/ghc"
 dac4b9d3/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="dac4b9d3cdca83c99d5d894d2743cc0bbca450ac"
 ByteCodeGen: use byte indexing for BCenv

 This is another change needed for #13825 (also based on D38 by Simon
 Marlow).

 With the change, we count the stack depth in bytes (instead of words).
 We also introduce some `newtype`s to help with the change.

 Note that this only changes how `ByteCodeGen` works and shouldn't
 affect the generated bytecode.

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

 Test Plan: ./validate

 Reviewers: bgamari, simonmar, austin, hvr

 Reviewed By: bgamari, simonmar

 Subscribers: rwbarton, thomie

 GHC Trac Issues: #13825

 Differential Revision: https://phabricator.haskell.org/D3746
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13825#comment:9>
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