t_acos.c revision 1.7 
1/* $NetBSD: t_acos.c,v 1.7 2014/03/03 10:38:36 martin Exp $ */
2
3/*-
4 * Copyright (c) 2011 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Jukka Ruohonen.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32#include <atf-c.h>
33#include <math.h>
34
35#ifdef HAVE_FENV_H
36#include <fenv.h>
37#endif
38
39/*
40 * Check result of fn(arg) is correct within the bounds.
41 * Should be ok to do the checks using 'double' for 'float' functions.
42 */
43#ifdef HAVE_FENV_H
44#define T_LIBM_CHECK(subtest, fn, arg, expect, epsilon) do { \
45	double r = fn(arg); \
46	double e = fabs(r - expect); \
47	if (e > epsilon) \
48		atf_tc_fail_nonfatal( \
49		    "subtest %zu: " #fn "(%g) is %g not %g (error %g > %g), roundmode %x", \
50		    subtest, arg, r, expect, e, epsilon, fegetround()); \
51    } while (0)
52#else
53#define T_LIBM_CHECK(subtest, fn, arg, expect, epsilon) do { \
54	double r = fn(arg); \
55	double e = fabs(r - expect); \
56	if (e > epsilon) \
57		atf_tc_fail_nonfatal( \
58		    "subtest %zu: " #fn "(%g) is %g not %g (error %g > %g)", \
59		    subtest, arg, r, expect, e, epsilon); \
60    } while (0)
61#endif
62
63/* Check that the result of fn(arg) is NaN */
64#ifndef __vax__
65#define T_LIBM_CHECK_NAN(subtest, fn, arg) do { \
66	double r = fn(arg); \
67	if (!isnan(r)) \
68		atf_tc_fail_nonfatal("subtest %zu: " #fn "(%g) is %g not NaN", \
69		    subtest, arg, r); \
70    } while (0)
71#else
72/* vax doesn't support NaN */
73#define T_LIBM_CHECK_NAN(subtest, fn, arg) (void)(arg)
74#endif
75
76#define AFT_LIBM_TEST(name, description) \
77ATF_TC(name); \
78ATF_TC_HEAD(name, tc) { atf_tc_set_md_var(tc, "descr", description); } \
79ATF_TC_BODY(name, tc)
80
81/*
82 * acos(3) and acosf(3)
83 */
84
85AFT_LIBM_TEST(acos_nan, "Test acos/acosf(x) == NaN, x = NaN, +/-Inf, ![-1..1]")
86{
87	static const double x[] = {
88	    -1.000000001, 1.000000001,
89	    -1.0000001, 1.0000001,
90	    -1.1, 1.1,
91#ifndef __vax__
92	    0.0L / 0.0L,  /* NAN */
93	    -1.0L / 0.0L, /* -Inf */
94	    +1.0L / 0.0L, /* +Inf */
95#endif
96	};
97	size_t i;
98
99	for (i = 0; i < __arraycount(x); i++) {
100		T_LIBM_CHECK_NAN(i, acos, x[i]);
101		if (i < 2)
102			/* Values are too small for float */
103			continue;
104		T_LIBM_CHECK_NAN(i, acosf, x[i]);
105	}
106}
107
108AFT_LIBM_TEST(acos_inrange, "Test acos/acosf(x) for some valid values")
109{
110	static const struct {
111		double x;
112		double y;
113	} values[] = {
114		{ -1,    M_PI,              },
115		{ -0.99, 3.000053180265366, },
116		{ -0.5,  2.094395102393195, },
117		{ -0.1,  1.670963747956456, },
118		{  0,    M_PI / 2,          },
119		{  0.1,  1.470628905633337, },
120		{  0.5,  1.047197551196598, },
121		{  0.99, 0.141539473324427, },
122	};
123	size_t i;
124
125	/*
126	 * Note that acos(x) might be calculated as atan2(sqrt(1-x*x),x).
127	 * This means that acos(-1) is atan2(+0,-1), if the sign is wrong
128	 * the value will be -M_PI (atan2(-0,-1)) not M_PI.
129	 */
130
131	for (i = 0; i < __arraycount(values); i++) {
132		T_LIBM_CHECK(i, acos, values[i].x, values[i].y, 1.0e-15);
133		T_LIBM_CHECK(i, acosf, values[i].x, values[i].y, 1.0e-5);
134	}
135}
136
137AFT_LIBM_TEST(acos_one_pos, "Test acos(1.0) == +0.0")
138{
139	const double y = acos(1.0);
140
141	if (fabs(y) > 0.0 || signbit(y) != 0)
142		atf_tc_fail_nonfatal("acos(1.0) != +0.0");
143}
144
145AFT_LIBM_TEST(acosf_one_pos, "Test acosf(1.0) == +0.0")
146{
147	const float y = acosf(1.0);
148
149	if (fabsf(y) > 0.0 || signbit(y) != 0)
150		atf_tc_fail_nonfatal("acosf(1.0) != +0.0");
151}
152
153ATF_TP_ADD_TCS(tp)
154{
155
156	ATF_TP_ADD_TC(tp, acos_nan);
157	ATF_TP_ADD_TC(tp, acos_inrange);
158	ATF_TP_ADD_TC(tp, acos_one_pos);
159	ATF_TP_ADD_TC(tp, acosf_one_pos);
160
161	return atf_no_error();
162}
163