Trivial code simplification

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@202073 91177308-0d34-0410-b5e6-96231b3b80d8
Add missing const

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@202074 91177308-0d34-0410-b5e6-96231b3b80d8
Fix DOT4 missing from getTargetOpcodeName

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@202075 91177308-0d34-0410-b5e6-96231b3b80d8
R600: Make check clearer.

The check is clearer as southern islands or later,
rather than checking for later than northern islands.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@202076 91177308-0d34-0410-b5e6-96231b3b80d8
R600/SI - Add new CI arithmetic instructions.

Does not yet include larger part required
to match v_mad_i64_i32 / v_mad_u64_u32.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@202077 91177308-0d34-0410-b5e6-96231b3b80d8