1 /* $OpenBSD: isinfl.c,v 1.2 2008/12/09 19:52:33 martynas Exp $ */ 2 /* 3 * Copyright (c) 2008 Martynas Venckus <martynas@openbsd.org> 4 * 5 * Permission to use, copy, modify, and distribute this software for any 6 * purpose with or without fee is hereby granted, provided that the above 7 * copyright notice and this permission notice appear in all copies. 8 * 9 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 11 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 15 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 16 */ 17 18 #include <sys/types.h> 19 #include <machine/ieee.h> 20 #include <math.h> 21 22 int 23 __isinfl(long double e) 24 { 25 struct ieee_ext *p = (struct ieee_ext *)&e; 26 27 p->ext_frach &= ~0x80000000; /* clear normalization bit */ 28 29 return (p->ext_exp == EXT_EXP_INFNAN && 30 p->ext_frach == 0 && p->ext_fracl == 0); 31 } 32