[GHC] #15536: Unify unlifted pointer equality primitives

[GHC]

#15536: Unify unlifted pointer equality primitives
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        Reporter:  dfeuer            |                Owner:  (none)
            Type:  feature request   |               Status:  new
        Priority:  normal            |            Milestone:  8.8.1
       Component:  Compiler          |              Version:  8.4.3
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by dfeuer):

 I started looking into implementation, and I see a couple wrinkles:

 1. The one that blocked me is that I don't know how to express the type I
 want in `primops.txt.pp`, if it's possible. Anyone know? If it's not
 possible, where would I have to override a bogus type with the correct
 one?

 2. `StableName#` is not implemented using a pointer equality test.
 Instead, it seems that we check the stable name table indices for
 equality. I don't, however, see a reason for this. Isn't there precisely
 one stable name object per stable name table entry?

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15536#comment:2>
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