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      1 /*-
      2  * Copyright (c) 2004 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 <sys/cdefs.h>
     28 /* __FBSDID("$FreeBSD: src/lib/msun/src/s_nearbyint.c,v 1.1 2004/07/06 04:46:08 das Exp $"); */
     29 
     30 #include <fenv.h>
     31 #include <math.h>
     32 
     33 /*
     34  * We save and restore the floating-point environment to avoid raising
     35  * an inexact exception.  We can get away with using fesetenv()
     36  * instead of feclearexcept()/feupdateenv() to restore the environment
     37  * because the only exception defined for rint() is overflow, and
     38  * rounding can't overflow as long as emax >= p.
     39  */
     40 #define	DECL(type, fn, rint)	\
     41 type				\
     42 fn(type x)			\
     43 {				\
     44 	type ret;		\
     45 	fenv_t env;		\
     46 				\
     47 	fegetenv(&env);		\
     48 	ret = rint(x);		\
     49 	fesetenv(&env);		\
     50 	return (ret);		\
     51 }
     52 
     53 DECL(double, nearbyint, rint)
     54 DECL(float, nearbyintf, rintf)
     55