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 __lrint = lrint
31
32 /*
33 * lrint(x) rounds its argument to the nearest integer according
34 * to the current rounding direction and converts the result to
35 * a 32 bit signed integer.
36 *
37 * If x is NaN, infinite, or so large that the nearest integer
38 * would exceed 32 bits, the invalid operation exception is raised.
39 * If x is not an integer, the inexact exception is raised.
40 */
41
42 #include <sys/isa_defs.h> /* _ILP32 */
43 #include "libm.h"
44
45 #if defined(_ILP32)
46 long
47 lrint(double x) {
48 /*
49 * Note: The following code works on x86 (in the default rounding
50 * precision mode), but one should just use the fistpl instruction
51 * instead.
52 */
53 union {
54 unsigned i[2];
55 double d;
56 } xx, yy;
57 unsigned hx;
58
59 xx.d = x;
60 hx = xx.i[HIWORD] & ~0x80000000;
61 if (hx < 0x43300000) { /* |x| < 2^52 */
62 /* add and subtract a power of two to round x to an integer */
63 #if defined(__sparc)
64 yy.i[HIWORD] = (xx.i[HIWORD] & 0x80000000) | 0x43300000;
65 #elif defined(__x86)
66 yy.i[HIWORD] = (xx.i[HIWORD] & 0x80000000) | 0x43e00000;
67 #else
68 #error Unknown architecture
69 #endif
70 yy.i[LOWORD] = 0;
71 x = (x + yy.d) - yy.d;
72 }
73
74 /* now x is nan, inf, or integral */
75 return ((long) x);
76 }
77 #else
78 #error Unsupported architecture
79 #endif /* defined(_ILP32) */
|
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 /*
27 * Copyright 2006 Sun Microsystems, Inc. All rights reserved.
28 * Use is subject to license terms.
29 */
30
31 #pragma weak __lrint = lrint
32
33 /*
34 * lrint(x) rounds its argument to the nearest integer according
35 * to the current rounding direction and converts the result to
36 * a 32 bit signed integer.
37 *
38 * If x is NaN, infinite, or so large that the nearest integer
39 * would exceed 32 bits, the invalid operation exception is raised.
40 * If x is not an integer, the inexact exception is raised.
41 */
42
43 #include <sys/isa_defs.h> /* _ILP32 */
44 #include "libm.h"
45
46 #if defined(_ILP32)
47 long
48 lrint(double x)
49 {
50 /*
51 * Note: The following code works on x86 (in the default rounding
52 * precision mode), but one should just use the fistpl instruction
53 * instead.
54 */
55 union {
56 unsigned i[2];
57 double d;
58 } xx, yy;
59
60 unsigned hx;
61
62 xx.d = x;
63 hx = xx.i[HIWORD] & ~0x80000000;
64
65 if (hx < 0x43300000) { /* |x| < 2^52 */
66 /* add and subtract a power of two to round x to an integer */
67 #if defined(__sparc)
68 yy.i[HIWORD] = (xx.i[HIWORD] & 0x80000000) | 0x43300000;
69 #elif defined(__x86)
70 yy.i[HIWORD] = (xx.i[HIWORD] & 0x80000000) | 0x43e00000;
71 #else
72 #error Unknown architecture
73 #endif
74 yy.i[LOWORD] = 0;
75 x = (x + yy.d) - yy.d;
76 }
77
78 /* now x is nan, inf, or integral */
79 return ((long)x);
80 }
81 #else
82 #error Unsupported architecture
83 #endif /* defined(_ILP32) */
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