[GHC] #7902: Add support for byte endianness swapping exposed as a primops

[GHC]

#7902: Add support for byte endianness swapping exposed as a primops
------------------------------------------+---------------------------------
  Reporter:  tab                          |          Owner:                  
      Type:  feature request              |         Status:  new             
  Priority:  normal                       |      Milestone:                  
 Component:  Compiler                     |        Version:  7.7             
Resolution:                               |       Keywords:  bswap endianness
        Os:  Unknown/Multiple             |   Architecture:  Unknown/Multiple
   Failure:  None/Unknown                 |     Difficulty:  Unknown         
  Testcase:  codeGen/should_run/cgrun072  |      Blockedby:                  
  Blocking:                               |        Related:                  
------------------------------------------+---------------------------------

Comment(by tab):

 ah #7976 is already a bit further than my investigation. So far i came to
 the same conclusion of the problem being the 64 bits flavor of byteSwap. I
 think the patch make sense (without considering the overlapping), the 32
 bit version for i386 definitely need a specific version for bswap64. I
 don't think it should be an issue with the 32 bits in general, as ppc and
 sparc (the other NCG platforms) will be handled with the C functions.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/7902#comment:15>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler