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

[GHC]

#7902: Add support for byte endianness swapping exposed as a primops
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        Reporter:  tab                          |            Owner:
            Type:  feature request              |           Status:  patch
        Priority:  normal                       |        Milestone:
       Component:  Compiler                     |          Version:  7.7
      Resolution:                               |         Keywords:  bswap
Operating System:  Unknown/Multiple             |  endianness
 Type of failure:  None/Unknown                 |     Architecture:
       Test Case:  codeGen/should_run/cgrun072  |  Unknown/Multiple
        Blocking:                               |       Difficulty:
                                                |  Unknown
                                                |       Blocked By:
                                                |  Related Tickets:
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Comment (by thoughtpolice):

 I've fixed up these patches to work with HEAD (minor changes in the LLVM
 code generator caused a merge conflict.)

 I'll push them, following validate doesn't complain on my Linux/Windows
 machines. Shouldn't take too long.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/7902#comment:21>
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