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 frexpl = __frexpl
31
32#include "libm.h"
33
34#if defined(__sparc)
35
36long double
37__frexpl(long double x, int *exp) {
38	union {
39		unsigned i[4];
40		long double q;
41	} xx;
42	unsigned hx;
43	int e, s;
44
45	xx.q = x;
46	hx = xx.i[0] & ~0x80000000;
47
48	if (hx >= 0x7fff0000) {	/* x is infinite or NaN */
49		*exp = 0;
50		return (x);
51	}
52
53	e = 0;
54	if (hx < 0x00010000) {	/* x is subnormal or zero */
55		if ((hx | xx.i[1] | xx.i[2] | xx.i[3]) == 0) {
56			*exp = 0;
57			return (x);
58		}
59
60		/* normalize x */
61		s = xx.i[0] & 0x80000000;
62		while ((hx | (xx.i[1] & 0xffff0000)) == 0) {
63			hx = xx.i[1];
64			xx.i[1] = xx.i[2];
65			xx.i[2] = xx.i[3];
66			xx.i[3] = 0;
67			e -= 32;
68		}
69		while (hx < 0x10000) {
70			hx = (hx << 1) | (xx.i[1] >> 31);
71			xx.i[1] = (xx.i[1] << 1) | (xx.i[2] >> 31);
72			xx.i[2] = (xx.i[2] << 1) | (xx.i[3] >> 31);
73			xx.i[3] <<= 1;
74			e--;
75		}
76		xx.i[0] = s | hx;
77	}
78
79	/* now xx.q is normal */
80	xx.i[0] = (xx.i[0] & ~0x7fff0000) | 0x3ffe0000;
81	*exp = e + (hx >> 16) - 0x3ffe;
82	return (xx.q);
83}
84
85#elif defined(__x86)
86
87long double
88__frexpl(long double x, int *exp) {
89	union {
90		unsigned i[3];
91		long double e;
92	} xx;
93	unsigned hx;
94	int e;
95
96	xx.e = x;
97	hx = xx.i[2] & 0x7fff;
98
99	if (hx >= 0x7fff) {	/* x is infinite or NaN */
100		*exp = 0;
101		return (x);
102	}
103
104	e = 0;
105	if (hx < 0x0001) {	/* x is subnormal or zero */
106		if ((xx.i[0] | xx.i[1]) == 0) {
107			*exp = 0;
108			return (x);
109		}
110
111		/* normalize x */
112		xx.e *= 18446744073709551616.0L;	/* 2^64 */
113		hx = xx.i[2] & 0x7fff;
114		e = -64;
115	}
116
117	/* now xx.e is normal */
118	xx.i[2] = (xx.i[2] & 0x8000) | 0x3ffe;
119	*exp = e + hx - 0x3ffe;
120	return (xx.e);
121}
122
123#else
124#error Unknown architecture
125#endif
126