.define .rol4 .sect .text .sect .rom .sect .data .sect .bss .sect .text ! Rotate 4 bytes left ! Expects in de-reg: number of rotates ! Expects on stack: operand ! Yields on stack: result .rol4 pop h shld .retadr mov h,b mov l,c shld .bcreg .rol4: pop h ! low-order bytes of operand pop b ! high order bytes of operand mov a,e ani 31 jz 2f mov e,a mov a,b ral 1: mov a,l ral mov l,a mov a,h ral mov h,a mov a,c ral mov c,a mov a,b ral mov b,a dcr e jnz 1b ! keep looping 2: push b push h lhld .bcreg mov b,h mov c,l lhld .retadr pchl