1 /*- 2 * Copyright (c) 2005 David Schultz <das@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