[GHC] #7883: enable GHC LLVM backend to use LLVM provided CAS / Atomicity primitives?

[GHC]

#7883: enable GHC LLVM backend to use LLVM provided CAS / Atomicity primitives?
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        Reporter:  carter            |            Owner:  carter
            Type:  feature request   |           Status:  new
        Priority:  normal            |        Milestone:
       Component:  Compiler          |          Version:  7.7
      Resolution:                    |         Keywords:
Operating System:  Unknown/Multiple  |     Architecture:  Unknown/Multiple
 Type of failure:  None/Unknown      |       Difficulty:  Unknown
       Test Case:                    |       Blocked By:
        Blocking:                    |  Related Tickets:
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Comment (by rrnewton):

 A couple additional suggestions copied over from the mailing list:

   (1) we should use more unique symbols than "cas", especially for this
 rewriting trick.  How about "ghc_cas" or something?

   (2) it would be great to get at least fetch-and-add in addition to CAS
 and barriers

   (3) if we reliably provide this set of special symbols, libraries like
 atomic-primops may use them in the .cmm and benefit from the CMM->LLVM
 substitutions

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/7883#comment:5>
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