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 #if defined(ELFOBJ)
31 #pragma weak aintf = __aintf
32 #pragma weak anintf = __anintf
33 #pragma weak irintf = __irintf
34 #pragma weak nintf = __nintf
35 #pragma weak rintf = __rintf
36 #endif
37
38 /* INDENT OFF */
39 /*
40 * aintf(x) return x chopped to integral value
41 * anintf(x) return sign(x)*(|x|+0.5) chopped to integral value
42 * irintf(x) return rint(x) in integer format
43 * nintf(x) return anint(x) in integer format
44 * rintf(x) return x rounded to integral according to the rounding direction
45 *
46 * NOTE: rintf(x), aintf(x) and anintf(x) return results with the same sign as
47 * x's, including 0.0.
48 */
49
50 #include "libm.h"
51
52 static const float xf[] = {
53 /* ZEROF */ 0.0f,
54 /* TWO_23F */ 8.3886080000e6f,
55 /* MTWO_23F */ -8.3886080000e6f,
56 /* ONEF */ 1.0f,
57 /* MONEF */ -1.0f,
58 /* HALFF */ 0.5f,
59 /* MHALFF */ -0.5f,
60 /* HUGEF */ 1.0e30f,
61 };
62
63 #define ZEROF xf[0]
64 #define TWO_23F xf[1]
65 #define MTWO_23F xf[2]
66 #define ONEF xf[3]
67 #define MONEF xf[4]
68 #define HALFF xf[5]
69 #define MHALFF xf[6]
70 #define HUGEF xf[7]
71 /* INDENT ON */
72
73 float
74 aintf(float x) {
75 int hx, k;
76 float y;
77
78 hx = *(int *) &x;
79 k = (hx & ~0x80000000) >> 23;
80 if (k < 150) {
81 y = (float) ((int) x);
82 /*
83 * make sure y has the same sign of x when |x|<0.5
84 * (i.e., y=0.0)
85 */
86 return (((k - 127) & hx) < 0 ? -y : y);
87 } else
88 /* signal invalid if x is a SNaN */
89 return (x * ONEF); /* +0 -> *1 for Cheetah */
90 }
91
92 float
93 anintf(float x) {
94 volatile float dummy;
95 int hx, k, j, ix;
96
97 hx = *(int *) &x;
98 ix = hx & ~0x80000000;
99 k = ix >> 23;
100 if (((k - 127) ^ (k - 150)) < 0) {
101 j = 1 << (149 - k);
102 k = j + j - 1;
103 if ((k & hx) != 0)
104 dummy = HUGEF + x; /* raise inexact */
105 *(int *) &x = (hx + j) & ~k;
106 return (x);
107 } else if (k <= 126) {
108 dummy = HUGEF + x;
109 *(int *) &x = (0x3f800000 & ((125 - k) >> 31)) |
110 (0x80000000 & hx);
111 return (x);
112 } else
113 /* signal invalid if x is a SNaN */
114 return (x * ONEF); /* +0 -> *1 for Cheetah */
115 }
116
117 int
118 irintf(float x) {
119 float v;
120 int hx, k;
121
122 hx = *(int *) &x;
123 k = (hx & ~0x80000000) >> 23;
124 v = xf[((k - 150) >> 31) & (1 - (hx >> 31))];
125 return ((int) ((float) (x + v) - v));
126 }
127
128 int
129 nintf(float x) {
130 int hx, ix, k, j, m;
131 volatile float dummy;
132
133 hx = *(int *) &x;
134 k = (hx & ~0x80000000) >> 23;
135 if (((k - 126) ^ (k - 150)) < 0) {
136 ix = (hx & 0x00ffffff) | 0x800000;
137 m = 149 - k;
138 j = 1 << m;
139 if ((ix & (j + j - 1)) != 0)
140 dummy = HUGEF + x;
141 hx = hx >> 31;
142 return ((((ix + j) >> (m + 1)) ^ hx) - hx);
143 } else
144 return ((int) x);
145 }
146
147 float
148 rintf(float x) {
149 float w, v;
150 int hx, k;
151
152 hx = *(int *) &x;
153 k = (hx & ~0x80000000) >> 23;
154 #if defined(FPADD_TRAPS_INCOMPLETE_ON_NAN)
155 if (k >= 150)
156 return (x * ONEF);
157 v = xf[1 - (hx >> 31)];
158 #else
159 v = xf[((k - 150) >> 31) & (1 - (hx >> 31))];
160 #endif
161 w = (float) (x + v);
162 if (k < 127 && w == v)
163 return (ZEROF * x);
164 else
165 return (w - v);
166 }