Copy segment register when optimizing to MOV8ao8/MOV16ao16/MOV32ao32.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199365 91177308-0d34-0410-b5e6-96231b3b80d8
AVX-512: fixed a compare pattern


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199366 91177308-0d34-0410-b5e6-96231b3b80d8