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 __nextafterf = nextafterf
31
32 #include "libm.h"
33
34 float
nextafterf(float x,float y)35 nextafterf(float x, float y) {
36 float w;
37 int *pw = (int *) &w;
38 int *px = (int *) &x;
39 int *py = (int *) &y;
40 int ix, iy, iz;
41
42 ix = px[0];
43 iy = py[0];
44 if ((ix & ~0x80000000) > 0x7f800000)
45 return (x * y); /* + -> * for Cheetah */
46 if ((iy & ~0x80000000) > 0x7f800000)
47 return (y * x); /* + -> * for Cheetah */
48 if (ix == iy || (ix | iy) == 0x80000000)
49 return (y); /* C99 requirement */
50 if ((ix & ~0x80000000) == 0)
51 iz = 1 | (iy & 0x80000000);
52 else if (ix > 0) {
53 if (ix > iy)
54 iz = ix - 1;
55 else
56 iz = ix + 1;
57 } else {
58 if (iy < 0 && ix < iy)
59 iz = ix + 1;
60 else
61 iz = ix - 1;
62 }
63 pw[0] = iz;
64 ix = iz & 0x7f800000;
65 if (ix == 0x7f800000) {
66 /* raise overflow */
67 volatile float t;
68
69 *(int *) &t = 0x7f7fffff;
70 t *= t;
71 } else if (ix == 0) {
72 /* raise underflow */
73 volatile float t;
74
75 *(int *) &t = 0x00800000;
76 t *= t;
77 }
78 return (w);
79 }
80