[GHC] #14375: Implement with# primop

[GHC]

#14375: Implement with# primop
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        Reporter:  simonpj           |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.2.1
      Resolution:                    |             Keywords:  JoinPoints
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #14346            |  Differential Rev(s):  ​Phab:D4110
       Wiki Page:                    |
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Comment (by bgamari):

 I'm not entirely sure I see what this means for the join point saturation
 invariant. Indeed we under no obligation to obey the say invariants
 surrounding join points that we obey in Core, but in that case what
 invariants are we obeying? Specifically, when is an unsaturated join point
 allowed?

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14375#comment:3>
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