This patch adds aliases for Mips sub instruction with immediate operands. Corresponding test cases are added.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191734 91177308-0d34-0410-b5e6-96231b3b80d8
Fix pattern sort in DAGISelEmitter.cpp

The old code skipped one of the sorting criteria if either pattern had
no types.  This could lead to cycles of the form X < Y, Y < Z, Z < X.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191735 91177308-0d34-0410-b5e6-96231b3b80d8