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

[GHC]

#8256: adding locality levels to prefetch# and friends
-------------------------------------+------------------------------------
        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
-------------------------------------+------------------------------------

Comment (by Austin Seipp <austin@?>):

 In [changeset:fd74014079f14bd3ab50e328e52c44ef97d40e05/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="fd74014079f14bd3ab50e328e52c44ef97d40e05"
 Add support for prefetch with locality levels.

 This patch adds support for several new primitive operations which
 support using processor-specific instructions to help guide data and
 cache locality decisions. We have levels ranging from [0..3]

 For LLVM, we generate llvm.prefetch intrinsics at the proper locality
 level (similar to GCC.)

 For x86 we generate prefetch{NTA, t2, t1, t0} instructions. On SPARC and
 PowerPC, the locality levels are ignored.

 This closes #8256.

 Authored-by: Carter Tazio Schonwald <carter.schonwald at gmail.com>
 Signed-off-by: Austin Seipp <austin at well-typed.com>
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8256#comment:32>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler