1/* IEEE754 floating point arithmetic
2 * double precision: common utilities
3 */
4/*
5 * MIPS floating point support
6 * Copyright (C) 1994-2000 Algorithmics Ltd.
7 * http://www.algor.co.uk
8 *
9 * ########################################################################
10 *
11 *  This program is free software; you can distribute it and/or modify it
12 *  under the terms of the GNU General Public License (Version 2) as
13 *  published by the Free Software Foundation.
14 *
15 *  This program is distributed in the hope it will be useful, but WITHOUT
16 *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
17 *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
18 *  for more details.
19 *
20 *  You should have received a copy of the GNU General Public License along
21 *  with this program; if not, write to the Free Software Foundation, Inc.,
22 *  59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
23 *
24 * ########################################################################
25 */
26
27
28#include "ieee754dp.h"
29
30ieee754dp ieee754dp_logb(ieee754dp x)
31{
32	COMPXDP;
33
34	CLEARCX;
35
36	EXPLODEXDP;
37
38	switch (xc) {
39	case IEEE754_CLASS_SNAN:
40		return ieee754dp_nanxcpt(x, "logb", x);
41	case IEEE754_CLASS_QNAN:
42		return x;
43	case IEEE754_CLASS_INF:
44		return ieee754dp_inf(0);
45	case IEEE754_CLASS_ZERO:
46		return ieee754dp_inf(1);
47	case IEEE754_CLASS_DNORM:
48		DPDNORMX;
49		break;
50	case IEEE754_CLASS_NORM:
51		break;
52	}
53	return ieee754dp_fint(xe);
54}
55