1 /*-
2 * Copyright (c) 2005 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 #include <limits.h>
28
29 /*
30 * If type has more precision than dtype, the endpoints dtype_(min|max) are
31 * of the form xxx.5; they are "out of range" because lround() rounds away
32 * from 0. On the other hand, if type has less precision than dtype, then
33 * all values that are out of range are integral, so we might as well assume
34 * that everything is in range. At compile time, INRANGE(x) should reduce to
35 * two floating-point comparisons in the former case, or TRUE otherwise.
36 */
37 static const type dtype_min = DTYPE_MIN - (type)0.5;
38 static const type dtype_max = DTYPE_MAX + (type)0.5;
39 #define INRANGE(x) (dtype_max - DTYPE_MAX != (type)0.5 || \
40 ((x) > dtype_min && (x) < dtype_max))
41
42 dtype
fn(type x)43 fn(type x)
44 {
45
46 if (INRANGE(x)) {
47 x = roundit(x);
48 return ((dtype)x);
49 } else {
50 #ifdef FE_INVALID
51 feraiseexcept(FE_INVALID);
52 #endif
53 return (DTYPE_MAX);
54 }
55 }
56
