xref: /dflybsd-src/contrib/openbsd_libm/src/s_lrintl.c (revision 4382f29d99a100bd77a81697c2f699c11f6a472a)
1*05a0b428SJohn Marino /*	$OpenBSD: s_lrintl.c,v 1.2 2012/12/05 23:20:04 deraadt Exp $	*/
2*05a0b428SJohn Marino 
3*05a0b428SJohn Marino /*-
4*05a0b428SJohn Marino  * Copyright (c) 2005 David Schultz <das@FreeBSD.ORG>
5*05a0b428SJohn Marino  * All rights reserved.
6*05a0b428SJohn Marino  *
7*05a0b428SJohn Marino  * Redistribution and use in source and binary forms, with or without
8*05a0b428SJohn Marino  * modification, are permitted provided that the following conditions
9*05a0b428SJohn Marino  * are met:
10*05a0b428SJohn Marino  * 1. Redistributions of source code must retain the above copyright
11*05a0b428SJohn Marino  *    notice, this list of conditions and the following disclaimer.
12*05a0b428SJohn Marino  * 2. Redistributions in binary form must reproduce the above copyright
13*05a0b428SJohn Marino  *    notice, this list of conditions and the following disclaimer in the
14*05a0b428SJohn Marino  *    documentation and/or other materials provided with the distribution.
15*05a0b428SJohn Marino  *
16*05a0b428SJohn Marino  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17*05a0b428SJohn Marino  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18*05a0b428SJohn Marino  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19*05a0b428SJohn Marino  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20*05a0b428SJohn Marino  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21*05a0b428SJohn Marino  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22*05a0b428SJohn Marino  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23*05a0b428SJohn Marino  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24*05a0b428SJohn Marino  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25*05a0b428SJohn Marino  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26*05a0b428SJohn Marino  * SUCH DAMAGE.
27*05a0b428SJohn Marino  */
28*05a0b428SJohn Marino 
29*05a0b428SJohn Marino #include <fenv.h>
30*05a0b428SJohn Marino #include <math.h>
31*05a0b428SJohn Marino 
32*05a0b428SJohn Marino #ifndef type
33*05a0b428SJohn Marino #if 0
34*05a0b428SJohn Marino __FBSDID("$FreeBSD: src/lib/msun/src/s_lrint.c,v 1.1 2005/01/11 23:12:55 das Exp $");
35*05a0b428SJohn Marino #endif
36*05a0b428SJohn Marino #define type		long double
37*05a0b428SJohn Marino #define	roundit		rintl
38*05a0b428SJohn Marino #define dtype		long
39*05a0b428SJohn Marino #define	fn		lrintl
40*05a0b428SJohn Marino #endif
41*05a0b428SJohn Marino 
42*05a0b428SJohn Marino /*
43*05a0b428SJohn Marino  * C99 says we should not raise a spurious inexact exception when an
44*05a0b428SJohn Marino  * invalid exception is raised.  Unfortunately, the set of inputs
45*05a0b428SJohn Marino  * that overflows depends on the rounding mode when 'dtype' has more
46*05a0b428SJohn Marino  * significant bits than 'type'.  Hence, we bend over backwards for the
47*05a0b428SJohn Marino  * sake of correctness; an MD implementation could be more efficient.
48*05a0b428SJohn Marino  */
49*05a0b428SJohn Marino dtype
fn(type x)50*05a0b428SJohn Marino fn(type x)
51*05a0b428SJohn Marino {
52*05a0b428SJohn Marino 	fenv_t env;
53*05a0b428SJohn Marino 	dtype d;
54*05a0b428SJohn Marino 
55*05a0b428SJohn Marino 	feholdexcept(&env);
56*05a0b428SJohn Marino 	d = (dtype)roundit(x);
57*05a0b428SJohn Marino 	if (fetestexcept(FE_INVALID))
58*05a0b428SJohn Marino 		feclearexcept(FE_INEXACT);
59*05a0b428SJohn Marino 	feupdateenv(&env);
60*05a0b428SJohn Marino 	return (d);
61*05a0b428SJohn Marino }
62