[GHC] #11179: Allow plugins to access "dead code"

[GHC]

#11179: Allow plugins to access "dead code"
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        Reporter:  lerkok            |                Owner:
            Type:  feature request   |               Status:  patch
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  7.10.2
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #10823            |  Differential Rev(s):  Phab:D3073
       Wiki Page:                    |
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Comment (by gridaphobe):

 I'm not sure that keeping dead top-level binders is sufficient. I believe
 that `simpleOptPgm` does other things that cause trouble for analysis
 tools. For example, IIRC it will automatically inline single-use,
 unexported binders.

 It would be nice if plugins could see a "faithful" representation of the
 source code, i.e. as close to the parsed HsSyn as possible. I realize this
 is a bit out of scope with respect to the original ticket, happy to file a
 separate ticket with a concrete example.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11179#comment:12>
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