1 /* $NetBSD: isinfl.c,v 1.5.16.1 2007/05/07 19:49:07 pavel Exp $ */
2
3 /*
4 * Copyright (c) 1992, 1993
5 * The Regents of the University of California. All rights reserved.
6 *
7 * This software was developed by the Computer Systems Engineering group
8 * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
9 * contributed to Berkeley.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * 3. Neither the name of the University nor the names of its contributors
20 * may be used to endorse or promote products derived from this software
21 * without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 *
35 * from: Header: isinf.c,v 1.1 91/07/08 19:03:34 torek Exp
36 */
37 #include <LibConfig.h>
38 #include <sys/EfiCdefs.h>
39 #if defined(LIBC_SCCS) && !defined(lint)
40 #if 0
41 static char sccsid[] = "@(#)isinf.c 8.1 (Berkeley) 6/4/93";
42 #else
43 __RCSID("$NetBSD: isinfl.c,v 1.5.16.1 2007/05/07 19:49:07 pavel Exp $");
44 #endif
45 #endif /* LIBC_SCCS and not lint */
46
47 #include <machine/ieee.h>
48 #include <math.h>
49
50 #if defined(_MSC_VER) /* Handle Microsoft VC++ compiler specifics. */
51 // C4700: uninitialized local variable used
52 #pragma warning ( disable : 4700 )
53 #endif
54
55 /*
56 * 7.12.3.3 isinf - test for infinity
57 * IEEE 754 compatible 80-bit extended-precision Intel 386 version
58 */
59 int
__isinfl(long double x)60 __isinfl(long double x)
61 {
62 union ieee_ext_u u;
63
64 u.extu_ld = x;
65
66 return (u.extu_ext.ext_exp == EXT_EXP_INFNAN &&
67 u.extu_ext.ext_frach == 0x80000000 && u.extu_ext.ext_fracl == 0);
68 }
69