[GHC] #16164: Provide bitreverse primop

[GHC]

#16164: Provide bitreverse primop
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        Reporter:  Fuuzetsu          |                Owner:  (none)
            Type:  feature request   |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.6.3
      Resolution:                    |             Keywords:  newcomer
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 rockbmb):

 I've got a couple of questions:

 1. Does the inexistence of such an operation in GCC mean such a primop
 would, at first, only be available when the compiler uses the LLVM
 backend?

 2. From the
 [understanding](https://ghc.haskell.org/trac/ghc/wiki/Commentary/PrimOps#AddinganewPrimOp)
 I've been gathering, am I right to assume that this primop will be out-of-
 line?

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/16164#comment:2>
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