s_lrint.c - vx32 - Local 9vx git repository for patches.
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---
s_lrint.c (2049B)
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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 <fenv.h>
28 #include <math.h>
29
30 #ifndef type
31 #define type double
32 #define roundit rint
33 #define dtype long
34 #define fn lrint
35 #endif
36
37 /*
38 * C99 says we should not raise a spurious inexact exception when an
39 * invalid exception is raised. Unfortunately, the set of inputs
40 * that overflows depends on the rounding mode when 'dtype' has more
41 * significant bits than 'type'. Hence, we bend over backwards for the
42 * sake of correctness; an MD implementation could be more efficient.
43 */
44 dtype
45 fn(type x)
46 {
47 fenv_t env;
48 dtype d;
49
50 feholdexcept(&env);
51 d = (dtype)roundit(x);
52 if (fetestexcept(FE_INVALID))
53 feclearexcept(FE_INEXACT);
54 feupdateenv(&env);
55 return (d);
56 }