ack/mach/m68k4/libem/los.s
1985-02-07 22:06:32 +00:00

37 lines
475 B
ArmAsm

.define .los
! d0 : # bytes
! a0 : source address
.text
.los:
movem.l d0/a0,.savreg
move.l (sp)+,.savret
move.l (sp)+,d0
move.l (sp)+,a0
cmp.l #1,d0
bne 1f
clr.l d0 !1 byte
move.b (a0),d0
move.l d0,-(sp)
bra 3f
1:
cmp.l #2,d0
bne 2f
clr.l d0 !2 bytes
add.l #2,a0
move.w (a0),d0
move.l d0,-(sp)
bra 3f
2:
add.l d0,a0 !>=4 bytes
asr.l #2,d0
4: move.l -(a0),-(sp)
sub.l #1,d0
bgt 4b
3:
movem.l .savreg,d0/a0
move.l .savret,-(sp)
rts
.align 2