xref: /freebsd/lib/msun/tests/trig_test.c (revision 5bf5ca772c6de2d53344a78cf461447cc322ccea)
1 /*-
2  * Copyright (c) 2008 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 /*
28  * Tests for corner cases in trigonometric functions. Some accuracy tests
29  * are included as well, but these are very basic sanity checks, not
30  * intended to be comprehensive.
31  *
32  * The program for generating representable numbers near multiples of pi is
33  * available at http://www.cs.berkeley.edu/~wkahan/testpi/ .
34  */
35 
36 #include <sys/cdefs.h>
37 __FBSDID("$FreeBSD$");
38 
39 #include <sys/param.h>
40 
41 #include <assert.h>
42 #include <fenv.h>
43 #include <float.h>
44 #include <math.h>
45 #include <stdio.h>
46 
47 #include <atf-c.h>
48 
49 #include "test-utils.h"
50 
51 #pragma STDC FENV_ACCESS ON
52 
53 /*
54  * Test that a function returns the correct value and sets the
55  * exception flags correctly. The exceptmask specifies which
56  * exceptions we should check. We need to be lenient for several
57  * reasons, but mainly because on some architectures it's impossible
58  * to raise FE_OVERFLOW without raising FE_INEXACT.
59  *
60  * These are macros instead of functions so that assert provides more
61  * meaningful error messages.
62  *
63  * XXX The volatile here is to avoid gcc's bogus constant folding and work
64  *     around the lack of support for the FENV_ACCESS pragma.
65  */
66 #define	test(func, x, result, exceptmask, excepts)	do {		\
67 	volatile long double _d = x;					\
68 	ATF_CHECK(feclearexcept(FE_ALL_EXCEPT) == 0);			\
69 	ATF_CHECK(fpequal((func)(_d), (result)));				\
70 	ATF_CHECK(((void)(func), fetestexcept(exceptmask) == (excepts)));	\
71 } while (0)
72 
73 #define	testall(prefix, x, result, exceptmask, excepts)	do {		\
74 	test(prefix, x, (double)result, exceptmask, excepts);		\
75 	test(prefix##f, x, (float)result, exceptmask, excepts);		\
76 	test(prefix##l, x, result, exceptmask, excepts);		\
77 } while (0)
78 
79 #define	testdf(prefix, x, result, exceptmask, excepts)	do {		\
80 	test(prefix, x, (double)result, exceptmask, excepts);		\
81 	test(prefix##f, x, (float)result, exceptmask, excepts);		\
82 } while (0)
83 
84 ATF_TC(special);
85 ATF_TC_HEAD(special, tc)
86 {
87 
88 	atf_tc_set_md_var(tc, "descr",
89  	    "test special cases in sin(), cos(), and tan()");
90 }
91 ATF_TC_BODY(special, tc)
92 {
93 
94 	/* Values at 0 should be exact. */
95 	testall(tan, 0.0, 0.0, ALL_STD_EXCEPT, 0);
96 	testall(tan, -0.0, -0.0, ALL_STD_EXCEPT, 0);
97 	testall(cos, 0.0, 1.0, ALL_STD_EXCEPT, 0);
98 	testall(cos, -0.0, 1.0, ALL_STD_EXCEPT, 0);
99 	testall(sin, 0.0, 0.0, ALL_STD_EXCEPT, 0);
100 	testall(sin, -0.0, -0.0, ALL_STD_EXCEPT, 0);
101 
102 	/* func(+-Inf) == NaN */
103 	testall(tan, INFINITY, NAN, ALL_STD_EXCEPT, FE_INVALID);
104 	testall(sin, INFINITY, NAN, ALL_STD_EXCEPT, FE_INVALID);
105 	testall(cos, INFINITY, NAN, ALL_STD_EXCEPT, FE_INVALID);
106 	testall(tan, -INFINITY, NAN, ALL_STD_EXCEPT, FE_INVALID);
107 	testall(sin, -INFINITY, NAN, ALL_STD_EXCEPT, FE_INVALID);
108 	testall(cos, -INFINITY, NAN, ALL_STD_EXCEPT, FE_INVALID);
109 
110 	/* func(NaN) == NaN */
111 	testall(tan, NAN, NAN, ALL_STD_EXCEPT, 0);
112 	testall(sin, NAN, NAN, ALL_STD_EXCEPT, 0);
113 	testall(cos, NAN, NAN, ALL_STD_EXCEPT, 0);
114 }
115 
116 #ifndef __i386__
117 ATF_TC(reduction);
118 ATF_TC_HEAD(reduction, tc)
119 {
120 
121 	atf_tc_set_md_var(tc, "descr",
122  	    "tests to ensure argument reduction for large arguments is accurate");
123 }
124 ATF_TC_BODY(reduction, tc)
125 {
126 	/* floats very close to odd multiples of pi */
127 	static const float f_pi_odd[] = {
128 		85563208.0f,
129 		43998769152.0f,
130 		9.2763667655669323e+25f,
131 		1.5458357838905804e+29f,
132 	};
133 	/* doubles very close to odd multiples of pi */
134 	static const double d_pi_odd[] = {
135 		3.1415926535897931,
136 		91.106186954104004,
137 		642615.9188844458,
138 		3397346.5699258847,
139 		6134899525417045.0,
140 		3.0213551960457761e+43,
141 		1.2646209897993783e+295,
142 		6.2083625380677099e+307,
143 	};
144 	/* long doubles very close to odd multiples of pi */
145 #if LDBL_MANT_DIG == 64
146 	static const long double ld_pi_odd[] = {
147 		1.1891886960373841596e+101L,
148 		1.07999475322710967206e+2087L,
149 		6.522151627890431836e+2147L,
150 		8.9368974898260328229e+2484L,
151 		9.2961044110572205863e+2555L,
152 		4.90208421886578286e+3189L,
153 		1.5275546401232615884e+3317L,
154 		1.7227465626338900093e+3565L,
155 		2.4160090594000745334e+3808L,
156 		9.8477555741888350649e+4314L,
157 		1.6061597222105160737e+4326L,
158 	};
159 #endif
160 
161 	unsigned i;
162 
163 	for (i = 0; i < nitems(f_pi_odd); i++) {
164 		ATF_CHECK(fabs(sinf(f_pi_odd[i])) < FLT_EPSILON);
165 		ATF_CHECK(cosf(f_pi_odd[i]) == -1.0);
166 		ATF_CHECK(fabs(tan(f_pi_odd[i])) < FLT_EPSILON);
167 
168 		ATF_CHECK(fabs(sinf(-f_pi_odd[i])) < FLT_EPSILON);
169 		ATF_CHECK(cosf(-f_pi_odd[i]) == -1.0);
170 		ATF_CHECK(fabs(tanf(-f_pi_odd[i])) < FLT_EPSILON);
171 
172 		ATF_CHECK(fabs(sinf(f_pi_odd[i] * 2)) < FLT_EPSILON);
173 		ATF_CHECK(cosf(f_pi_odd[i] * 2) == 1.0);
174 		ATF_CHECK(fabs(tanf(f_pi_odd[i] * 2)) < FLT_EPSILON);
175 
176 		ATF_CHECK(fabs(sinf(-f_pi_odd[i] * 2)) < FLT_EPSILON);
177 		ATF_CHECK(cosf(-f_pi_odd[i] * 2) == 1.0);
178 		ATF_CHECK(fabs(tanf(-f_pi_odd[i] * 2)) < FLT_EPSILON);
179 	}
180 
181 	for (i = 0; i < nitems(d_pi_odd); i++) {
182 		ATF_CHECK(fabs(sin(d_pi_odd[i])) < 2 * DBL_EPSILON);
183 		ATF_CHECK(cos(d_pi_odd[i]) == -1.0);
184 		ATF_CHECK(fabs(tan(d_pi_odd[i])) < 2 * DBL_EPSILON);
185 
186 		ATF_CHECK(fabs(sin(-d_pi_odd[i])) < 2 * DBL_EPSILON);
187 		ATF_CHECK(cos(-d_pi_odd[i]) == -1.0);
188 		ATF_CHECK(fabs(tan(-d_pi_odd[i])) < 2 * DBL_EPSILON);
189 
190 		ATF_CHECK(fabs(sin(d_pi_odd[i] * 2)) < 2 * DBL_EPSILON);
191 		ATF_CHECK(cos(d_pi_odd[i] * 2) == 1.0);
192 		ATF_CHECK(fabs(tan(d_pi_odd[i] * 2)) < 2 * DBL_EPSILON);
193 
194 		ATF_CHECK(fabs(sin(-d_pi_odd[i] * 2)) < 2 * DBL_EPSILON);
195 		ATF_CHECK(cos(-d_pi_odd[i] * 2) == 1.0);
196 		ATF_CHECK(fabs(tan(-d_pi_odd[i] * 2)) < 2 * DBL_EPSILON);
197 	}
198 
199 #if LDBL_MANT_DIG == 64 /* XXX: || LDBL_MANT_DIG == 113 */
200 	for (i = 0; i < nitems(ld_pi_odd); i++) {
201 		ATF_CHECK(fabsl(sinl(ld_pi_odd[i])) < LDBL_EPSILON);
202 		ATF_CHECK(cosl(ld_pi_odd[i]) == -1.0);
203 		ATF_CHECK(fabsl(tanl(ld_pi_odd[i])) < LDBL_EPSILON);
204 
205 		ATF_CHECK(fabsl(sinl(-ld_pi_odd[i])) < LDBL_EPSILON);
206 		ATF_CHECK(cosl(-ld_pi_odd[i]) == -1.0);
207 		ATF_CHECK(fabsl(tanl(-ld_pi_odd[i])) < LDBL_EPSILON);
208 
209 		ATF_CHECK(fabsl(sinl(ld_pi_odd[i] * 2)) < LDBL_EPSILON);
210 		ATF_CHECK(cosl(ld_pi_odd[i] * 2) == 1.0);
211 		ATF_CHECK(fabsl(tanl(ld_pi_odd[i] * 2)) < LDBL_EPSILON);
212 
213 		ATF_CHECK(fabsl(sinl(-ld_pi_odd[i] * 2)) < LDBL_EPSILON);
214 		ATF_CHECK(cosl(-ld_pi_odd[i] * 2) == 1.0);
215 		ATF_CHECK(fabsl(tanl(-ld_pi_odd[i] * 2)) < LDBL_EPSILON);
216 	}
217 #endif
218 }
219 
220 ATF_TC(accuracy);
221 ATF_TC_HEAD(accuracy, tc)
222 {
223 
224 	atf_tc_set_md_var(tc, "descr",
225 	    "tests the accuracy of these functions over the primary range");
226 }
227 ATF_TC_BODY(accuracy, tc)
228 {
229 
230 	/* For small args, sin(x) = tan(x) = x, and cos(x) = 1. */
231 	testall(sin, 0xd.50ee515fe4aea16p-114L, 0xd.50ee515fe4aea16p-114L,
232 	     ALL_STD_EXCEPT, FE_INEXACT);
233 	testall(tan, 0xd.50ee515fe4aea16p-114L, 0xd.50ee515fe4aea16p-114L,
234 	     ALL_STD_EXCEPT, FE_INEXACT);
235 	testall(cos, 0xd.50ee515fe4aea16p-114L, 1.0,
236 		ALL_STD_EXCEPT, FE_INEXACT);
237 
238 	/*
239 	 * These tests should pass for f32, d64, and ld80 as long as
240 	 * the error is <= 0.75 ulp (round to nearest)
241 	 */
242 #if LDBL_MANT_DIG <= 64
243 #define	testacc	testall
244 #else
245 #define	testacc	testdf
246 #endif
247 	testacc(sin, 0.17255452780841205174L, 0.17169949801444412683L,
248 		ALL_STD_EXCEPT, FE_INEXACT);
249 	testacc(sin, -0.75431944555904520893L, -0.68479288156557286353L,
250 		ALL_STD_EXCEPT, FE_INEXACT);
251 	testacc(cos, 0.70556358769838947292L, 0.76124620693117771850L,
252 		ALL_STD_EXCEPT, FE_INEXACT);
253 	testacc(cos, -0.34061437849088045332L, 0.94254960031831729956L,
254 		ALL_STD_EXCEPT, FE_INEXACT);
255 	testacc(tan, -0.15862817413325692897L, -0.15997221861309522115L,
256 		ALL_STD_EXCEPT, FE_INEXACT);
257 	testacc(tan, 0.38374784931303813530L, 0.40376500259976759951L,
258 		ALL_STD_EXCEPT, FE_INEXACT);
259 
260 	/*
261 	 * XXX missing:
262 	 * - tests for ld128
263 	 * - tests for other rounding modes (probably won't pass for now)
264 	 * - tests for large numbers that get reduced to hi+lo with lo!=0
265 	 */
266 }
267 #endif
268 
269 ATF_TP_ADD_TCS(tp)
270 {
271 
272 	ATF_TP_ADD_TC(tp, special);
273 
274 #ifndef __i386__
275 	ATF_TP_ADD_TC(tp, accuracy);
276 	ATF_TP_ADD_TC(tp, reduction);
277 #endif
278 
279 	return (atf_no_error());
280 }
281