[GHC] #8949: switch -msse2 to be on by default

[GHC]

#8949: switch -msse2 to be on by default
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        Reporter:  errge                    |                Owner:  (none)
            Type:  bug                      |               Status:  new
        Priority:  high                     |            Milestone:  8.4.1
       Component:  Compiler (CodeGen)       |              Version:  7.9
      Resolution:                           |             Keywords:
Operating System:  Unknown/Multiple         |         Architecture:  x86
 Type of failure:  Runtime performance bug  |            Test Case:
      Blocked By:                           |             Blocking:
 Related Tickets:  #13540                   |  Differential Rev(s):
       Wiki Page:                           |
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Comment (by bgamari):

 Phyx points out in ticket:13540#comment:4 that,

 > neither the linux elf nor Windows GHCi linkers (non-dynamic way)
 currently honor section alignment. so using SSE2 more aggressively would
 likely cause issues here.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8949#comment:10>
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