[GHC] #4102: Bit manipulation built-ins

[GHC]

#4102: Bit manipulation built-ins
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    Reporter:  uzytkownik        |        Owner:              
        Type:  feature request   |       Status:  new         
    Priority:  normal            |    Milestone:  6.16.1      
   Component:  libraries/base    |      Version:  6.12.2      
    Keywords:                    |     Testcase:              
   Blockedby:                    |   Difficulty:              
          Os:  Unknown/Multiple  |     Blocking:              
Architecture:  Unknown/Multiple  |      Failure:  None/Unknown
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Comment(by gwicke):

 Replying to [comment:5 uzytkownik]:
 > I would strongly suggest Data.Bits for the following reasons:
 >
 >  - All of them can be implemented in terms of the Data.Bits primitives.
 It is simply an extention for specialization.
 >  - They should be handled in-line by compiler as for many architectures
 they can be optimized to single instruction. LLVM inline shoul handle it
 perfectly.

 Is it possible to do this optimization without requiring new primops and
 have it work across GHC backends? Could this be implemented using rules?

 My package is just a stop-gap measure to get access to native
 instructions, so I do not think this code would be suitable for Data.Bits.
 Maybe- if there is a way to use e.g. CPP to select the implementation by
 backend- some of this code could be used in the -fvia-C or -fasm
 implementations.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/4102#comment:6>
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