Implement aarch64 neon instruction set AdvSIMD (copy).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@192410 91177308-0d34-0410-b5e6-96231b3b80d8
LiveRangeCalc.h: Update a description corresponding to r192396. [-Wdocumentation]

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@192421 91177308-0d34-0410-b5e6-96231b3b80d8