/*      $OpenBSD: modsi3.S,v 1.1 2013/06/07 17:31:31 miod Exp $ */

/*
 * Copyright (c) 2013 Miodrag Vallat.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */


#include <machine/asm.h>

/*
 * int __modsi3(int n, int d);
 */

ENTRY(__modsi3)
        /* if divider is zero, trap */
        bcnd    ne0, %r3, 1f
        tb0     0, %r0, 503
1:

        bb1     31, %r2, 1f
        bb1     31, %r3, 2f

        /* both operands are positive */
        divu    %r4, %r2, %r3
9:
        mul     %r5, %r4, %r3
        jmp.n   %r1
         subu   %r2, %r2, %r5

1:
        bb1     31, %r3, 3f

        /* r2 is negative, r3 is positive */
        subu    %r4, %r0, %r2
        divu    %r5, %r4, %r3
        subu    %r4, %r0, %r5
        br      9b

2:
        /* r2 is positive, r3 is negative */
        subu    %r5, %r0, %r3
        divu    %r4, %r2, %r5
        subu    %r4, %r0, %r4
        br      9b

3:
        /* both operands are negative */
        subu    %r4, %r0, %r2
        subu    %r5, %r0, %r3
        divu    %r4, %r4, %r5
        br      9b
END(__modsi3)