1 /*-
2 * Copyright (c) 2004 David Schultz <das@FreeBSD.ORG>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27
28 #include <limits.h>
29
30 long double
scalbl(long double x,long double fn)31 scalbl (long double x, long double fn)
32 {
33 if (isnanl_inline(fn) || isnanl_inline(x))
34 return x + fn;
35
36 if (isinf(fn)) {
37 if ((x == 0.0L && fn > 0.0L) || (isinf(x) && fn < 0.0L))
38 return __math_invalidl(fn);
39 if (fn > 0.0L)
40 return fn*x;
41 else
42 return x/(-fn);
43 }
44
45 if (floorl(fn) != fn)
46 return __math_invalidl(fn);
47
48 if (fn > 4.0L * __LDBL_MAX_EXP__)
49 fn = 4.0L * __LDBL_MAX_EXP__;
50
51 if (fn < -4.0L * __LDBL_MAX_EXP__)
52 fn = -4.0L * __LDBL_MAX_EXP__;
53
54 return scalbnl(x, (int)fn);
55 }
56
