[GHC] #14818: Provide highestOneBit function in Data.Bits module

[GHC]

#14818: Provide highestOneBit function in Data.Bits module
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        Reporter:  kostmo            |                Owner:  (none)
            Type:  feature request   |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  libraries/base    |              Version:  8.2.2
      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 bgamari):

 If I understand correctly, we already have these:

  * `countLeadingZeros` is `GHC.Prim.clzN#`, which is exposed by
 `Data.Bits.countLeadingZeros`.
  * `highestOneBit` is `GHC.Prim.ctzN#`, which is exposed by
 `Data.Bits.countTrailingZeros`

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14818#comment:2>
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