- Added support to do aribitrary 4 wide shuffle with no more than three   instructions. - Fixed a commute vector_shuff bug.
- Added support to do aribitrary 4 wide shuffle with no more than three
  instructions.
- Fixed a commute vector_shuff bug.


git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@27845 91177308-0d34-0410-b5e6-96231b3b80d8

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