dp_simple.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_finite(ieee754dp x)
{
    return DPBEXP(x) != DP_EMAX + 1 + DP_EBIAS;
}

ieee754dp ieee754dp_copysign(ieee754dp x, ieee754dp y)
{
    CLEARCX;
    DPSIGN(x) = DPSIGN(y);
    return x;
}


ieee754dp ieee754dp_neg(ieee754dp x)
{
    COMPXDP;

    EXPLODEXDP;
    CLEARCX;
    FLUSHXDP;

    /*
     * Invert the sign ALWAYS to prevent an endless recursion on
     * pow() in libc.
     */
    /* quick fix up */
    DPSIGN(x) ^= 1;

    if (xc == IEEE754_CLASS_SNAN) {
        ieee754dp y = ieee754dp_indef();
        SETCX(IEEE754_INVALID_OPERATION);
        DPSIGN(y) = DPSIGN(x);
        return ieee754dp_nanxcpt(y, "neg");
    }

    return x;
}


ieee754dp ieee754dp_abs(ieee754dp x)
{
    COMPXDP;

    EXPLODEXDP;
    CLEARCX;
    FLUSHXDP;

    /* Clear sign ALWAYS, irrespective of NaN */
    DPSIGN(x) = 0;

    if (xc == IEEE754_CLASS_SNAN) {
        SETCX(IEEE754_INVALID_OPERATION);
        return ieee754dp_nanxcpt(ieee754dp_indef(), "abs");
    }

    return x;
}