[GHC] #8256: adding locality levels to prefetch# and friends

[GHC]

#8256: adding locality levels to prefetch# and friends
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        Reporter:  carter            |            Owner:  carter
            Type:  task              |           Status:  patch
        Priority:  normal            |        Milestone:  7.8.1
       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:  #8252 ,#8107
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Comment (by carter):

 well, there wasn't much discussion on the mailing list about whether
 can_fail is correct nor not!

 but to recap the mailing list reasons I laid out:

 1. I think we're ok with inlining duplicating a prefetch operation

 2. I'm not sure if we want to be ok with floating out prefetches (doing a
 prefetch earlier than planned). This is the reason for doing the can_fail
 = True annotation.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8256#comment:29>
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