Net2/usr/src/usr.bin/lisp/franz/tahoe/dodiv.c

/* Copyright (c) 1982, Regents, University of California */

struct sdot
       {long I;
	struct sdot *CDR;
       };
struct vl
       {long high;
        long low;
       };

long dodiv(top,bottom)
long *top, *bottom; /* top least significant; bottom most */
{
	struct vl work;
	char error;
	register long *p = bottom;	/* r12 */
	register long rem = 0;		/* r11 */

	for(;p <= top;p++)
	{
	/*	emul(0x40000000,rem,*p,&work);		*/
	/*	*p = ediv(&work,1000000000,&error);	*/
	/*	rem = work.high;			*/

		asm("emul	$0x40000000,r11,(r12),r0");
		asm("ediv	$1000000000,r0,(r12),r11");
	}
	return(rem);
}

long dsneg(top,bottom)
long *top, *bottom;
{
	register long *p = top;
	register carry = 0;
	register digit;

	while(p >= bottom)
	{
		digit = carry - *p;
		/* carry = digit >> 30; is slow on 68K */
		if(digit < 0) carry = -2;
		if(digit & 0x40000000) carry += 1;
		*p-- = digit & 0x3fffffff;
	}
}