Complement-Label
The complement of a label is found by taking each
no-operation instruction that makes up that label,
and shifting it to the next in alphabetical order, looping around at the end.
Thus, in the default instruction set, nop-A -> nop-B -> nop-C -> nop-A. The label
"nop-B nop-A nop-C nop-C" has the complement "nop-C nop-B nop-A nop-A".