Add isSubRegisterEq() and isSuperRegisterEq().

isSub and isSuper return false if RegA == RegB. Add variants which also
include the identity function.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170609 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed