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
30int ieee754dp_finite(ieee754dp x)
31{
32	return DPBEXP(x) != DP_EMAX + 1 + DP_EBIAS;
33}
34
35ieee754dp ieee754dp_copysign(ieee754dp x, ieee754dp y)
36{
37	CLEARCX;
38	DPSIGN(x) = DPSIGN(y);
39	return x;
40}
41
42
43ieee754dp ieee754dp_neg(ieee754dp x)
44{
45	COMPXDP;
46
47	EXPLODEXDP;
48	CLEARCX;
49	FLUSHXDP;
50
51	/*
52	 * Invert the sign ALWAYS to prevent an endless recursion on
53	 * pow() in libc.
54	 */
55	/* quick fix up */
56	DPSIGN(x) ^= 1;
57
58	if (xc == IEEE754_CLASS_SNAN) {
59		ieee754dp y = ieee754dp_indef();
60		SETCX(IEEE754_INVALID_OPERATION);
61		DPSIGN(y) = DPSIGN(x);
62		return ieee754dp_nanxcpt(y, "neg");
63	}
64
65	if (ieee754dp_isnan(x))	/* but not infinity */
66		return ieee754dp_nanxcpt(x, "neg", x);
67	return x;
68}
69
70
71ieee754dp ieee754dp_abs(ieee754dp x)
72{
73	COMPXDP;
74
75	EXPLODEXDP;
76	CLEARCX;
77	FLUSHXDP;
78
79	if (xc == IEEE754_CLASS_SNAN) {
80		SETCX(IEEE754_INVALID_OPERATION);
81		return ieee754dp_nanxcpt(ieee754dp_indef(), "neg");
82	}
83
84	if (ieee754dp_isnan(x))	/* but not infinity */
85		return ieee754dp_nanxcpt(x, "abs", x);
86
87	/* quick fix up */
88	DPSIGN(x) = 0;
89	return x;
90}
91