1 /* $NetBSD: t_round.c,v 1.3 2011/09/13 08:58:41 jruoho Exp $ */ 2 3 /*- 4 * Copyright (c) 2011 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 17 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 18 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 19 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 20 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 26 * POSSIBILITY OF SUCH DAMAGE. 27 */ 28 29 #include <atf-c.h> 30 #include <math.h> 31 32 /* 33 * This tests for a bug in the initial implementation where 34 * precision was lost in an internal substraction, leading to 35 * rounding into the wrong direction. 36 */ 37 38 /* 0.5 - EPSILON */ 39 #define VAL 0x0.7ffffffffffffcp0 40 #define VALF 0x0.7fffff8p0 41 42 #ifdef __vax__ 43 #define SMALL_NUM 1.0e-38 44 #else 45 #define SMALL_NUM 1.0e-40 46 #endif 47 48 ATF_TC(round_dir); 49 ATF_TC_HEAD(round_dir, tc) 50 { 51 atf_tc_set_md_var(tc, "descr","Check for rounding in wrong direction"); 52 } 53 54 ATF_TC_BODY(round_dir, tc) 55 { 56 double a = VAL, b, c; 57 float af = VALF, bf, cf; 58 59 b = round(a); 60 bf = roundf(af); 61 62 ATF_CHECK(fabs(b) < SMALL_NUM); 63 ATF_CHECK(fabsf(bf) < SMALL_NUM); 64 65 c = round(-a); 66 cf = roundf(-af); 67 68 ATF_CHECK(fabs(c) < SMALL_NUM); 69 ATF_CHECK(fabsf(cf) < SMALL_NUM); 70 } 71 72 ATF_TP_ADD_TCS(tp) 73 { 74 75 ATF_TP_ADD_TC(tp, round_dir); 76 77 return atf_no_error(); 78 } 79