ack/mach/i80/libem/rol4.s
1987-01-28 18:57:04 +00:00

53 lines
574 B
ArmAsm

.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