1
2/*
3 * Copyright (c) 1998, 2001, Oracle and/or its affiliates. All rights reserved.
4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
5 *
6 * This code is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License version 2 only, as
8 * published by the Free Software Foundation. Oracle designates this
9 * particular file as subject to the "Classpath" exception as provided
10 * by Oracle in the LICENSE file that accompanied this code.
11 *
12 * This code is distributed in the hope that it will be useful, but WITHOUT
13 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15 * version 2 for more details (a copy is included in the LICENSE file that
16 * accompanied this code).
17 *
18 * You should have received a copy of the GNU General Public License version
19 * 2 along with this work; if not, write to the Free Software Foundation,
20 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
21 *
22 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
23 * or visit www.oracle.com if you need additional information or have any
24 * questions.
25 */
26
27/*
28 * wrapper exp(x)
29 */
30
31#include "fdlibm.h"
32
33#ifdef __STDC__
34static const double
35#else
36static double
37#endif
38o_threshold= 7.09782712893383973096e+02, /* 0x40862E42, 0xFEFA39EF */
39u_threshold= -7.45133219101941108420e+02; /* 0xc0874910, 0xD52D3051 */
40
41#ifdef __STDC__
42 double exp(double x) /* wrapper exp */
43#else
44 double exp(x) /* wrapper exp */
45 double x;
46#endif
47{
48#ifdef _IEEE_LIBM
49 return __ieee754_exp(x);
50#else
51 double z;
52 z = __ieee754_exp(x);
53 if(_LIB_VERSION == _IEEE_) return z;
54 if(finite(x)) {
55 if(x>o_threshold)
56 return __kernel_standard(x,x,6); /* exp overflow */
57 else if(x<u_threshold)
58 return __kernel_standard(x,x,7); /* exp underflow */
59 }
60 return z;
61#endif
62}
63