- movlp{s|d} and movhp{s|d} support.

- movlp{s|d} and movhp{s|d} support.
- Normalize shuffle nodes so result vector lower half elements come from the
  first vector, the rest come from the second vector. (Except for the
  exceptions :-).
- Other minor fixes.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27474 91177308-0d34-0410-b5e6-96231b3b80d8