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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("$FreeBSD$");
     29 
     30 #include <math.h>
     31 
     32 #include "fpmath.h"
     33 
     34 double
     35 fmin(double x, double y)
     36 {
     37 	union IEEEd2bits u[2];
     38 
     39 	u[0].d = x;
     40 	u[1].d = y;
     41 
     42 	/* Check for NaNs to avoid raising spurious exceptions. */
     43 	if (u[0].bits.exp == 2047 && (u[0].bits.manh | u[0].bits.manl) != 0)
     44 		return (y);
     45 	if (u[1].bits.exp == 2047 && (u[1].bits.manh | u[1].bits.manl) != 0)
     46 		return (x);
     47 
     48 	/* Handle comparisons of signed zeroes. */
     49 	if (u[0].bits.sign != u[1].bits.sign)
     50 		return (u[u[1].bits.sign].d);
     51 
     52 	return (x < y ? x : y);
     53 }
     54