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      1 /*-
      2  * Copyright (c) 2005 David Schultz <das (at) 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 "namespace.h"
     28 
     29 #include <sys/cdefs.h>
     30 #include <fenv.h>
     31 #include <math.h>
     32 
     33 #ifndef stype
     34 #ifdef __FreeBSD__
     35 __FBSDID("$FreeBSD: head/lib/msun/src/s_lrint.c 140088 2005-01-11 23:12:55Z das $");
     36 #else
     37 __RCSID("$NetBSD: s_lrint.c,v 1.1 2017/05/06 18:03:24 christos Exp $");
     38 #endif
     39 #define stype		double
     40 #define	roundit		rint
     41 #define dtype		long
     42 #define	fn		lrint
     43 #endif
     44 
     45 /*
     46  * C99 says we should not raise a spurious inexact exception when an
     47  * invalid exception is raised.  Unfortunately, the set of inputs
     48  * that overflows depends on the rounding mode when 'dtype' has more
     49  * significant bits than 'stype'.  Hence, we bend over backwards for the
     50  * sake of correctness; an MD implementation could be more efficient.
     51  */
     52 dtype
     53 fn(stype x)
     54 {
     55 	fenv_t env;
     56 	dtype d;
     57 
     58 	feholdexcept(&env);
     59 	d = (dtype)roundit(x);
     60 	if (fetestexcept(FE_INVALID))
     61 		feclearexcept(FE_INEXACT);
     62 	feupdateenv(&env);
     63 	return (d);
     64 }
     65