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 modff = __modff
31 #pragma weak _modff = __modff
32
33 #include "libm.h"
34
35 float
__modff(float x,float * iptr)36 __modff(float x, float *iptr) {
37 union {
38 unsigned i;
39 float f;
40 } xx, yy;
41 unsigned hx, s;
42
43 xx.f = x;
44 hx = xx.i & ~0x80000000;
45
46 if (hx >= 0x4b000000) { /* x is NaN, infinite, or integral */
47 *iptr = x;
48 if (hx <= 0x7f800000)
49 xx.i &= 0x80000000;
50 return (xx.f);
51 }
52
53 if (hx < 0x3f800000) { /* |x| < 1 */
54 xx.i &= 0x80000000;
55 *iptr = xx.f;
56 return (x);
57 }
58
59 /* split x at the binary point */
60 s = xx.i & 0x80000000;
61 yy.i = xx.i & ~((1 << (0x96 - (hx >> 23))) - 1);
62 *iptr = yy.f;
63 xx.f -= yy.f;
64 xx.i = (xx.i & ~0x80000000) | s;
65 /* restore sign in case difference is 0 */
66 return (xx.f);
67 }
68