ref: a2baa8634834b462a613ff6cc74becee2efc9a3c dir: /sys/src/libc/68000/strcpy.s/
TEXT strcpy(SB), $0 MOVL s1+0(FP), A2 MOVL s2+4(FP), A1 l1: MOVB (A1)+, (A2)+ BNE l1 MOVL s1+0(FP), R0 RTS