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