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, Version 1.0 only
6 * (the "License"). You may not use this file except in compliance
7 * with the License.
8 *
9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10 * or http://www.opensolaris.org/os/licensing.
11 * See the License for the specific language governing permissions
12 * and limitations under the License.
13 *
14 * When distributing Covered Code, include this CDDL HEADER in each
15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16 * If applicable, add the following below this CDDL HEADER, with the
17 * fields enclosed by brackets "[]" replaced with your own identifying
18 * information: Portions Copyright [yyyy] [name of copyright owner]
19 *
20 * CDDL HEADER END
21 */
22 /*
23 * Copyright (c) 1994-1997, by Sun Microsystems, Inc.
24 * All rights reserved.
25 */
26
27 #pragma ident "%Z%%M% %I% %E% SMI"
28
29 /*
30 * __dtoul(x) converts double x to unsigned long.
31 */
32 unsigned long
__dtoul(double x)33 __dtoul(double x)
34 {
35 union {
36 double d;
37 unsigned long l;
38 } u;
39
40 u.d = x;
41
42 /* handle cases for which double->unsigned long differs from */
43 /* double->signed long */
44 if ((u.l >> 52) == 0x43e) {
45 /* 2^63 <= x < 2^64 */
46 return (0x8000000000000000ul | (u.l << 11));
47 }
48
49 /* for all other cases, just convert to signed long */
50 return ((long)x);
51 }
52