1 /* $OpenBSD: s_fmax.c,v 1.4 2008/12/10 01:08:24 martynas Exp $ */ 2 /*- 3 * Copyright (c) 2004 David Schultz <das@FreeBSD.ORG> 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 */ 27 28 #include <sys/cdefs.h> 29 #include <float.h> 30 #include <math.h> 31 32 double 33 fmax(double x, double y) 34 { 35 /* Check for NaNs to avoid raising spurious exceptions. */ 36 if (isnan(x)) 37 return (y); 38 if (isnan(y)) 39 return (x); 40 41 /* Handle comparisons of signed zeroes. */ 42 if (signbit(x) != signbit(y)) 43 if (signbit(x)) 44 return (y); 45 else 46 return (x); 47 48 return (x > y ? x : y); 49 } 50 51 #if LDBL_MANT_DIG == 53 52 #ifdef __weak_alias 53 __weak_alias(fmaxl, fmax); 54 #endif /* __weak_alias */ 55 #endif /* LDBL_MANT_DIG == 53 */ 56