sparcv9/fp/_Qp_qtox.c

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright (c) 1994-1997, by Sun Microsystems, Inc.
 * All rights reserved.
 */

#pragma ident   "%Z%%M% %I% %E% SMI"

#include "quad.h"

/*
 * _Qp_qtox(x) returns (long)*x.
 */
long
_Qp_qtox(const union longdouble *x)
{
    long        i, round;
    unsigned int    xm, fsr;

    xm = x->l.msw & 0x7fffffff;

    __quad_getfsrp(&fsr);

    /* handle nan, inf, and out-of-range cases */
    if (xm >= 0x403e0000) {
        if (x->l.msw == 0xc03e0000 && x->l.frac2 == 0 &&
            (x->l.frac3 & 0xfffe0000) == 0) {
            /* return largest negative 64 bit int */
            i = 0x8000000000000000ul;
            if ((x->l.frac3 & 0x1ffff) | x->l.frac4) {
                /* signal inexact */
                if (fsr & FSR_NXM) {
                    __quad_fqtox(x, &i);
                } else {
                    fsr = (fsr & ~FSR_CEXC) | FSR_NXA |
                        FSR_NXC;
                    __quad_setfsrp(&fsr);
                }
            }
            return (i);
        }
        i = ((x->l.msw & 0x80000000)? 0x8000000000000000ul :
            0x7fffffffffffffffl);
        if (fsr & FSR_NVM) {
            __quad_fqtox(x, &i);
        } else {
            fsr = (fsr & ~FSR_CEXC) | FSR_NVA | FSR_NVC;
            __quad_setfsrp(&fsr);
        }
        return (i);
    }
    if (xm < 0x3fff0000) {
        i = 0l;
        if (xm | x->l.frac2 | x->l.frac3 | x->l.frac4) {
            /* signal inexact */
            if (fsr & FSR_NXM) {
                __quad_fqtox(x, &i);
            } else {
                fsr = (fsr & ~FSR_CEXC) | FSR_NXA | FSR_NXC;
                __quad_setfsrp(&fsr);
            }
        }
        return (i);
    }

    /* now x is in the range of 64 bit int */
    i = 0x4000000000000000l | ((long) (xm & 0xffff) << 46) |
        ((long) x->l.frac2 << 14) | (x->l.frac3 >> 18);
    round = i & ((1l << (0x403d - (xm >> 16))) - 1);
    i >>= (0x403d - (xm >> 16));
    if (x->l.msw & 0x80000000)
        i = -i;
    if (round | (x->l.frac3 & 0x3ffff) | x->l.frac4) {
        /* signal inexact */
        if (fsr & FSR_NXM) {
            __quad_fqtox(x, &i);
        } else {
            fsr = (fsr & ~FSR_CEXC) | FSR_NXA | FSR_NXC;
            __quad_setfsrp(&fsr);
        }
    }
    return (i);
}