== Optimization ==
* RLA, RRA, RLCA, RRCA are essentially optimized versions , one byte smaller and one M-cycle faster, of RL A, RR A, RLC A, RRC A.* Unconditional JR and JP take the same amount of time on CPC but JR is one byte shorter.
* Many programs use XOR A to set A to zero, since it's one byte smaller and one M-cycle faster than LD A,0.
* Likewise, many programs use AND A or OR A to check if A is zero, since it's also one byte smaller and one M-cycle faster than CP 0.