usr/src/lib/libc/tahoe/gen/udiv.s

/*
 * Copyright (c) 1988 Regents of the University of California.
 * All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Computer Consoles Inc.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by the University of
 *      California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#if defined(LIBC_SCCS) && !defined(lint)
        .asciz "@(#)udiv.s      5.1 (Berkeley) 1/30/91"
#endif /* LIBC_SCCS and not lint */

/*
 * Unsigned divide.
 *
 * udiv(dividend, divisor)
 */
#include "DEFS.h"

ASENTRY(udiv, 0)
        bitl    $0x80000000,8(fp)       #  if (divisor & 0x80000000){
        jeql    1f
        cmpl    8(fp),4(fp)             #  if (divisor > dividend )
        jlequ   2f
        clrl    r0                      #      return(0);
        ret
2:                                      #  else
        movl    $1,r0                   #      return(1);}
        ret
1:
        clrl    r2                      #  return(dividend/divisor);
        movl    4(fp),r3
        ediv    8(fp),r2,r0,r1
        ret

/*
 * audiv(dividendp, divisor) -- like udiv but uses address of dividend.
 *      Implements /= avoiding side effects in the dividend expression.
 */
ASENTRY(audiv, 0)
        bitl    $0x80000000,8(fp)       #  if (divisor & 0x80000000){
        jeql    1f
        cmpl    8(fp),*4(fp)            #  if (divisor > dividend )
        jlequ   2f
        clrl    r0                      #      return(0);
        jbr     3f
2:                                      #  else
        movl    $1,r0                   #      return(1);}
        jbr     3f
1:
        clrl    r2                      #  return(dividend/divisor);
        movl    *4(fp),r3
        ediv    8(fp),r2,r0,r1
3:
        movl    r0,*4(fp)
        ret