dp_cmp.c

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/* IEEE754 floating point arithmetic
 * double precision: common utilities
 */
/*
 * MIPS floating point support
 * Copyright (C) 1994-2000 Algorithmics Ltd.
 *
 * ########################################################################
 *
 *  This program is free software; you can distribute it and/or modify it
 *  under the terms of the GNU General Public License (Version 2) as
 *  published by the Free Software Foundation.
 *
 *  This program is distributed in the hope it will be useful, but WITHOUT
 *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 *  for more details.
 *
 *  You should have received a copy of the GNU General Public License along
 *  with this program; if not, write to the Free Software Foundation, Inc.,
 *  59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
 *
 * ########################################################################
 */


#include "ieee754dp.h"

int ieee754dp_cmp(ieee754dp x, ieee754dp y, int cmp, int sig)
{
    COMPXDP;
    COMPYDP;

    EXPLODEXDP;
    EXPLODEYDP;
    FLUSHXDP;
    FLUSHYDP;
    CLEARCX;    /* Even clear inexact flag here */

    if (ieee754dp_isnan(x) || ieee754dp_isnan(y)) {
        if (sig || xc == IEEE754_CLASS_SNAN || yc == IEEE754_CLASS_SNAN)
            SETCX(IEEE754_INVALID_OPERATION);
        if (cmp & IEEE754_CUN)
            return 1;
        if (cmp & (IEEE754_CLT | IEEE754_CGT)) {
            if (sig && SETANDTESTCX(IEEE754_INVALID_OPERATION))
                return ieee754si_xcpt(0, "fcmpf", x);
        }
        return 0;
    } else {
        s64 vx = x.bits;
        s64 vy = y.bits;

        if (vx < 0)
            vx = -vx ^ DP_SIGN_BIT;
        if (vy < 0)
            vy = -vy ^ DP_SIGN_BIT;

        if (vx < vy)
            return (cmp & IEEE754_CLT) != 0;
        else if (vx == vy)
            return (cmp & IEEE754_CEQ) != 0;
        else
            return (cmp & IEEE754_CGT) != 0;
    }
}