.define cuu cuu: popl RR2, *RR14 pop R0, *RR14 pop R1, *RR14 sub R0, R1 !expansion in bytes jr LE, 1f sra R0 !expansion in words jp EQ, *RR2 2: push *RR14, $0 djnz R0, 2b jp *RR2 1: sub R15, R0 jp *RR2