xref: /titanic_51/usr/src/lib/libm/common/m9x/nan.c (revision 90b1de135fcfa7ce4adc9138a885aa94bbcef04f)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.
24  */
25 /*
26  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
27  * Use is subject to license terms.
28  */
29 
30 #pragma weak nan = __nan
31 
32 /*
33  *  nan(c) returns a NaN.  This implementation ignores c.
34  */
35 
36 #include "libm.h"
37 #include <sys/isa_defs.h>
38 
39 #if defined(__sparc)
40 
41 static const union {
42 	unsigned i[2];
43 	double d;
44 } __nan_union = { 0x7fffffff, 0xffffffff };
45 
46 #elif defined(__i386) || defined(__amd64)
47 
48 static const union {
49 	unsigned i[2];
50 	double d;
51 } __nan_union = { 0xffffffff, 0x7fffffff };
52 
53 #else
54 #error Unknown architecture
55 #endif
56 
57 /* ARGSUSED0 */
58 double
59 __nan(const char *c) {
60 	return (__nan_union.d);
61 }
62