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

[GHC]

#8949: switch -msse2 to be on by default
-------------------------------------+-------------------------------------
        Reporter:  errge             |            Owner:
            Type:  bug               |           Status:  new
        Priority:  normal            |        Milestone:
       Component:  Compiler          |          Version:  7.9
  (CodeGen)                          |         Keywords:
      Resolution:                    |     Architecture:  x86
Operating System:  Unknown/Multiple  |       Difficulty:  Moderate (less
 Type of failure:  Other             |  than a day)
       Test Case:                    |       Blocked By:
        Blocking:                    |  Related Tickets:
-------------------------------------+-------------------------------------

Comment (by tibbe):

 I'm fine with only doing `-msse2` for now.

 The amount of benefit we'll get from `-march=native` is growing. We're
 adding more intelligence to the code generator (e.g. `memcpy` will soon
 unroll to wider instructions if the target supports it, we have `popcnt`
 and `bswap`) and compiling with `-fllvm` should benefit too e.g. as code
 for the vector package would presumably compile to better assembly.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8949#comment:6>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler