1e0fe8e44SDavid Schultz /*-
2*4d846d26SWarner Losh * SPDX-License-Identifier: BSD-2-Clause
35e53a4f9SPedro F. Giffuni *
4e0fe8e44SDavid Schultz * Copyright (c) 2004-2005 David Schultz <das@FreeBSD.ORG>
5e0fe8e44SDavid Schultz * All rights reserved.
6e0fe8e44SDavid Schultz *
7e0fe8e44SDavid Schultz * Redistribution and use in source and binary forms, with or without
8e0fe8e44SDavid Schultz * modification, are permitted provided that the following conditions
9e0fe8e44SDavid Schultz * are met:
10e0fe8e44SDavid Schultz * 1. Redistributions of source code must retain the above copyright
11e0fe8e44SDavid Schultz * notice, this list of conditions and the following disclaimer.
12e0fe8e44SDavid Schultz * 2. Redistributions in binary form must reproduce the above copyright
13e0fe8e44SDavid Schultz * notice, this list of conditions and the following disclaimer in the
14e0fe8e44SDavid Schultz * documentation and/or other materials provided with the distribution.
15e0fe8e44SDavid Schultz *
16e0fe8e44SDavid Schultz * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17e0fe8e44SDavid Schultz * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18e0fe8e44SDavid Schultz * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19e0fe8e44SDavid Schultz * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20e0fe8e44SDavid Schultz * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21e0fe8e44SDavid Schultz * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22e0fe8e44SDavid Schultz * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23e0fe8e44SDavid Schultz * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24e0fe8e44SDavid Schultz * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25e0fe8e44SDavid Schultz * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26e0fe8e44SDavid Schultz * SUCH DAMAGE.
27e0fe8e44SDavid Schultz */
28e0fe8e44SDavid Schultz
29e0fe8e44SDavid Schultz #include <float.h>
30e0fe8e44SDavid Schultz #include <math.h>
31e0fe8e44SDavid Schultz
32e0fe8e44SDavid Schultz #include "fpmath.h"
33e0fe8e44SDavid Schultz
34e0fe8e44SDavid Schultz #if LDBL_MAX_EXP != 0x4000
35e0fe8e44SDavid Schultz #error "Unsupported long double format"
36e0fe8e44SDavid Schultz #endif
37e0fe8e44SDavid Schultz
38e0fe8e44SDavid Schultz long double
frexpl(long double x,int * ex)39e0fe8e44SDavid Schultz frexpl(long double x, int *ex)
40e0fe8e44SDavid Schultz {
41e0fe8e44SDavid Schultz union IEEEl2bits u;
42e0fe8e44SDavid Schultz
43e0fe8e44SDavid Schultz u.e = x;
44e0fe8e44SDavid Schultz switch (u.bits.exp) {
45e0fe8e44SDavid Schultz case 0: /* 0 or subnormal */
46e0fe8e44SDavid Schultz if ((u.bits.manl | u.bits.manh) == 0) {
47e0fe8e44SDavid Schultz *ex = 0;
48e0fe8e44SDavid Schultz } else {
49e0fe8e44SDavid Schultz u.e *= 0x1.0p514;
50e0fe8e44SDavid Schultz *ex = u.bits.exp - 0x4200;
51e0fe8e44SDavid Schultz u.bits.exp = 0x3ffe;
52e0fe8e44SDavid Schultz }
53e0fe8e44SDavid Schultz break;
54e0fe8e44SDavid Schultz case 0x7fff: /* infinity or NaN; value of *ex is unspecified */
55e0fe8e44SDavid Schultz break;
56e0fe8e44SDavid Schultz default: /* normal */
57e0fe8e44SDavid Schultz *ex = u.bits.exp - 0x3ffe;
58e0fe8e44SDavid Schultz u.bits.exp = 0x3ffe;
59e0fe8e44SDavid Schultz break;
60e0fe8e44SDavid Schultz }
61e0fe8e44SDavid Schultz return (u.e);
62e0fe8e44SDavid Schultz }
63