root/usr/src/lib/libc/sparc/fp/_Q_qtou.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.
 */

#include "quad.h"

#ifdef __sparcv9
#define _Q_qtou _Qp_qtoui
#endif

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

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

        __quad_getfsrp(&fsr);

        /* handle nan, inf, and out-of-range cases */
        if (xm >= 0x401e0000) {
                if (x->l.msw < 0x401f0000) {
                        i = 0x80000000 | ((xm & 0xffff) << 15) |
                            (x->l.frac2 >> 17);
                        if ((x->l.frac2 & 0x1ffff) | x->l.frac3 | x->l.frac4) {
                                /* signal inexact */
                                if (fsr & FSR_NXM) {
                                        /* z = x - 2^31 */
                                        if (xm & 0xffff ||
                                            x->l.frac2 & 0xffff0000) {
                                                z.l.msw = xm & 0xffff;
                                                z.l.frac2 = x->l.frac2;
                                                z.l.frac3 = x->l.frac3;
                                                z.l.frac4 = x->l.frac4;
                                        } else if (x->l.frac2 & 0xffff ||
                                            x->l.frac3 & 0xffff0000) {
                                                z.l.msw = x->l.frac2;
                                                z.l.frac2 = x->l.frac3;
                                                z.l.frac3 = x->l.frac4;
                                                z.l.frac4 = 0;
                                        } else if (x->l.frac3 & 0xffff ||
                                            x->l.frac4 & 0xffff0000) {
                                                z.l.msw = x->l.frac3;
                                                z.l.frac2 = x->l.frac4;
                                                z.l.frac3 = z.l.frac4 = 0;
                                        } else {
                                                z.l.msw = x->l.frac4;
                                                z.l.frac2 = z.l.frac3 =
                                                    z.l.frac4 = 0;
                                        }
                                        xm = 0x401e;
                                        while ((z.l.msw & 0x10000) == 0) {
                                                z.l.msw = (z.l.msw << 1) |
                                                    (z.l.frac2 >> 31);
                                                z.l.frac2 = (z.l.frac2 << 1) |
                                                    (z.l.frac3 >> 31);
                                                z.l.frac3 = (z.l.frac3 << 1) |
                                                    (z.l.frac4 >> 31);
                                                z.l.frac4 <<= 1;
                                                xm--;
                                        }
                                        z.l.msw |= (xm << 16);
                                        __quad_fqtoi(&z, &i);
                                        i |= 0x80000000;
                                } else {
                                        fsr = (fsr & ~FSR_CEXC) | FSR_NXA |
                                            FSR_NXC;
                                        __quad_setfsrp(&fsr);
                                }
                        }
                        return (i);
                }
                if (x->l.msw == 0xc01e0000 && (x->l.frac2 & 0xfffe0000) == 0) {
                        /* return largest negative int */
                        i = 0x80000000;
                        if ((x->l.frac2 & 0x1ffff) | x->l.frac3 | x->l.frac4) {
                                /* signal inexact */
                                if (fsr & FSR_NXM) {
                                        __quad_fqtoi(x, &i);
                                } else {
                                        fsr = (fsr & ~FSR_CEXC) | FSR_NXA |
                                            FSR_NXC;
                                        __quad_setfsrp(&fsr);
                                }
                        }
                        return (i);
                }
                i = ((x->l.msw & 0x80000000)? 0x80000000 : 0x7fffffff);
                if (fsr & FSR_NVM) {
                        __quad_fqtoi(x, &i);
                } else {
                        fsr = (fsr & ~FSR_CEXC) | FSR_NVA | FSR_NVC;
                        __quad_setfsrp(&fsr);
                }
                return (i);
        }
        if (xm < 0x3fff0000) {
                if (xm | x->l.frac2 | x->l.frac3 | x->l.frac4) {
                        /* signal inexact */
                        i = 0;
                        if (fsr & FSR_NXM) {
                                __quad_fqtoi(x, &i);
                        } else {
                                fsr = (fsr & ~FSR_CEXC) | FSR_NXA | FSR_NXC;
                                __quad_setfsrp(&fsr);
                        }
                        return (i);
                }
                return (0);
        }

        /* now x is in the range of int */
        i = 0x40000000 | ((xm & 0xffff) << 14) | (x->l.frac2 >> 18);
        round = i & ((1 << (0x401d - (xm >> 16))) - 1);
        i >>= (0x401d - (xm >> 16));
        if (x->l.msw & 0x80000000)
                i = -i;
        if (round | (x->l.frac2 & 0x3ffff) | x->l.frac3 | x->l.frac4) {
                /* signal inexact */
                if (fsr & FSR_NXM) {
                        __quad_fqtoi(x, &i);
                } else {
                        fsr = (fsr & ~FSR_CEXC) | FSR_NXA | FSR_NXC;
                        __quad_setfsrp(&fsr);
                }
        }
        return (i);
}