minix/lib/i86/em/em_rmi4.s
2005-04-21 14:53:53 +00:00

89 lines
1.1 KiB
ArmAsm
Executable file

.define .rmi4
.text
yl=6
yh=8
xl=10
xh=12
.rmi4:
push si
push di
mov si,sp ! copy of sp
mov bx,yl(si)
mov ax,yh(si)
cwd
cmp dx,ax
jne 7f
and dx,dx
jge 1f
neg bx
je 7f
1:
xor dx,dx
mov cx,xl(si)
mov ax,xh(si)
and ax,ax
jge 2f
neg ax
neg cx
sbb ax,dx
2:
div bx
xchg ax,cx
div bx ! dx= result(low), 0=result(high)
xor bx,bx
9:
cmp xh(si),#0
jge 1f
neg bx
neg dx
sbb bx,#0
1:
! bx is high order result
! dx is low order result
mov ax,dx
mov dx,bx ! result in ax/dx
pop di
pop si
ret 8
7:
mov di,ax
xor bx,bx
and di,di
jge 1f
neg di
neg yl(si)
sbb di,bx
1:
mov ax,xl(si)
mov dx,xh(si)
and dx,dx
jge 1f
neg dx
neg ax
sbb dx,bx
1:
mov cx,#16
1:
shl ax,#1
rcl dx,#1
rcl bx,#1
cmp di,bx
ja 3f
jb 2f
cmp yl(si),dx
jbe 2f
3:
loop 1b
! dx=result(low), bx=result(high)
jmp 9b
2:
sub dx,yl(si)
sbb bx,di
inc ax
loop 1b
1:
! dx=result(low), bx=result(high)
jmp 9b