xref: /freebsd/lib/msun/tests/cexp_test.c (revision d6b92ffa)
1 /*-
2  * Copyright (c) 2008-2011 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 cexp*().
29  */
30 
31 #include <sys/cdefs.h>
32 __FBSDID("$FreeBSD$");
33 
34 #include <sys/param.h>
35 
36 #include <assert.h>
37 #include <complex.h>
38 #include <fenv.h>
39 #include <float.h>
40 #include <math.h>
41 #include <stdio.h>
42 
43 #include "test-utils.h"
44 
45 #pragma STDC FENV_ACCESS	ON
46 #pragma	STDC CX_LIMITED_RANGE	OFF
47 
48 /*
49  * Test that a function returns the correct value and sets the
50  * exception flags correctly. The exceptmask specifies which
51  * exceptions we should check. We need to be lenient for several
52  * reasons, but mainly because on some architectures it's impossible
53  * to raise FE_OVERFLOW without raising FE_INEXACT. In some cases,
54  * whether cexp() raises an invalid exception is unspecified.
55  *
56  * These are macros instead of functions so that assert provides more
57  * meaningful error messages.
58  *
59  * XXX The volatile here is to avoid gcc's bogus constant folding and work
60  *     around the lack of support for the FENV_ACCESS pragma.
61  */
62 #define	test(func, z, result, exceptmask, excepts, checksign)	do {	\
63 	volatile long double complex _d = z;				\
64 	assert(feclearexcept(FE_ALL_EXCEPT) == 0);			\
65 	assert(cfpequal_cs((func)(_d), (result), (checksign)));		\
66 	assert(((void)(func), fetestexcept(exceptmask) == (excepts)));	\
67 } while (0)
68 
69 /* Test within a given tolerance. */
70 #define	test_tol(func, z, result, tol)				do {	\
71 	volatile long double complex _d = z;				\
72 	assert(cfpequal_tol((func)(_d), (result), (tol),		\
73 	    FPE_ABS_ZERO | CS_BOTH));					\
74 } while (0)
75 
76 /* Test all the functions that compute cexp(x). */
77 #define	testall(x, result, exceptmask, excepts, checksign)	do {	\
78 	test(cexp, x, result, exceptmask, excepts, checksign);		\
79 	test(cexpf, x, result, exceptmask, excepts, checksign);		\
80 } while (0)
81 
82 /*
83  * Test all the functions that compute cexp(x), within a given tolerance.
84  * The tolerance is specified in ulps.
85  */
86 #define	testall_tol(x, result, tol)				do {	\
87 	test_tol(cexp, x, result, tol * DBL_ULP());			\
88 	test_tol(cexpf, x, result, tol * FLT_ULP());			\
89 } while (0)
90 
91 /* Various finite non-zero numbers to test. */
92 static const float finites[] =
93 { -42.0e20, -1.0, -1.0e-10, -0.0, 0.0, 1.0e-10, 1.0, 42.0e20 };
94 
95 
96 /* Tests for 0 */
97 static void
98 test_zero(void)
99 {
100 
101 	/* cexp(0) = 1, no exceptions raised */
102 	testall(0.0, 1.0, ALL_STD_EXCEPT, 0, 1);
103 	testall(-0.0, 1.0, ALL_STD_EXCEPT, 0, 1);
104 	testall(CMPLXL(0.0, -0.0), CMPLXL(1.0, -0.0), ALL_STD_EXCEPT, 0, 1);
105 	testall(CMPLXL(-0.0, -0.0), CMPLXL(1.0, -0.0), ALL_STD_EXCEPT, 0, 1);
106 }
107 
108 /*
109  * Tests for NaN.  The signs of the results are indeterminate unless the
110  * imaginary part is 0.
111  */
112 static void
113 test_nan(void)
114 {
115 	unsigned i;
116 
117 	/* cexp(x + NaNi) = NaN + NaNi and optionally raises invalid */
118 	/* cexp(NaN + yi) = NaN + NaNi and optionally raises invalid (|y|>0) */
119 	for (i = 0; i < nitems(finites); i++) {
120 		printf("# Run %d..\n", i);
121 		testall(CMPLXL(finites[i], NAN), CMPLXL(NAN, NAN),
122 			ALL_STD_EXCEPT & ~FE_INVALID, 0, 0);
123 		if (finites[i] == 0.0)
124 			continue;
125 		/* XXX FE_INEXACT shouldn't be raised here */
126 		testall(CMPLXL(NAN, finites[i]), CMPLXL(NAN, NAN),
127 			ALL_STD_EXCEPT & ~(FE_INVALID | FE_INEXACT), 0, 0);
128 	}
129 
130 	/* cexp(NaN +- 0i) = NaN +- 0i */
131 	testall(CMPLXL(NAN, 0.0), CMPLXL(NAN, 0.0), ALL_STD_EXCEPT, 0, 1);
132 	testall(CMPLXL(NAN, -0.0), CMPLXL(NAN, -0.0), ALL_STD_EXCEPT, 0, 1);
133 
134 	/* cexp(inf + NaN i) = inf + nan i */
135 	testall(CMPLXL(INFINITY, NAN), CMPLXL(INFINITY, NAN),
136 		ALL_STD_EXCEPT, 0, 0);
137 	/* cexp(-inf + NaN i) = 0 */
138 	testall(CMPLXL(-INFINITY, NAN), CMPLXL(0.0, 0.0),
139 		ALL_STD_EXCEPT, 0, 0);
140 	/* cexp(NaN + NaN i) = NaN + NaN i */
141 	testall(CMPLXL(NAN, NAN), CMPLXL(NAN, NAN),
142 		ALL_STD_EXCEPT, 0, 0);
143 }
144 
145 static void
146 test_inf(void)
147 {
148 	unsigned i;
149 
150 	/* cexp(x + inf i) = NaN + NaNi and raises invalid */
151 	for (i = 0; i < nitems(finites); i++) {
152 		printf("# Run %d..\n", i);
153 		testall(CMPLXL(finites[i], INFINITY), CMPLXL(NAN, NAN),
154 			ALL_STD_EXCEPT, FE_INVALID, 1);
155 	}
156 	/* cexp(-inf + yi) = 0 * (cos(y) + sin(y)i) */
157 	/* XXX shouldn't raise an inexact exception */
158 	testall(CMPLXL(-INFINITY, M_PI_4), CMPLXL(0.0, 0.0),
159 		ALL_STD_EXCEPT & ~FE_INEXACT, 0, 1);
160 	testall(CMPLXL(-INFINITY, 3 * M_PI_4), CMPLXL(-0.0, 0.0),
161 		ALL_STD_EXCEPT & ~FE_INEXACT, 0, 1);
162 	testall(CMPLXL(-INFINITY, 5 * M_PI_4), CMPLXL(-0.0, -0.0),
163 		ALL_STD_EXCEPT & ~FE_INEXACT, 0, 1);
164 	testall(CMPLXL(-INFINITY, 7 * M_PI_4), CMPLXL(0.0, -0.0),
165 		ALL_STD_EXCEPT & ~FE_INEXACT, 0, 1);
166 	testall(CMPLXL(-INFINITY, 0.0), CMPLXL(0.0, 0.0),
167 		ALL_STD_EXCEPT, 0, 1);
168 	testall(CMPLXL(-INFINITY, -0.0), CMPLXL(0.0, -0.0),
169 		ALL_STD_EXCEPT, 0, 1);
170 	/* cexp(inf + yi) = inf * (cos(y) + sin(y)i) (except y=0) */
171 	/* XXX shouldn't raise an inexact exception */
172 	testall(CMPLXL(INFINITY, M_PI_4), CMPLXL(INFINITY, INFINITY),
173 		ALL_STD_EXCEPT & ~FE_INEXACT, 0, 1);
174 	testall(CMPLXL(INFINITY, 3 * M_PI_4), CMPLXL(-INFINITY, INFINITY),
175 		ALL_STD_EXCEPT & ~FE_INEXACT, 0, 1);
176 	testall(CMPLXL(INFINITY, 5 * M_PI_4), CMPLXL(-INFINITY, -INFINITY),
177 		ALL_STD_EXCEPT & ~FE_INEXACT, 0, 1);
178 	testall(CMPLXL(INFINITY, 7 * M_PI_4), CMPLXL(INFINITY, -INFINITY),
179 		ALL_STD_EXCEPT & ~FE_INEXACT, 0, 1);
180 	/* cexp(inf + 0i) = inf + 0i */
181 	testall(CMPLXL(INFINITY, 0.0), CMPLXL(INFINITY, 0.0),
182 		ALL_STD_EXCEPT, 0, 1);
183 	testall(CMPLXL(INFINITY, -0.0), CMPLXL(INFINITY, -0.0),
184 		ALL_STD_EXCEPT, 0, 1);
185 }
186 
187 static void
188 test_reals(void)
189 {
190 	unsigned i;
191 
192 	for (i = 0; i < nitems(finites); i++) {
193 		/* XXX could check exceptions more meticulously */
194 		printf("# Run %d..\n", i);
195 		test(cexp, CMPLXL(finites[i], 0.0),
196 		     CMPLXL(exp(finites[i]), 0.0),
197 		     FE_INVALID | FE_DIVBYZERO, 0, 1);
198 		test(cexp, CMPLXL(finites[i], -0.0),
199 		     CMPLXL(exp(finites[i]), -0.0),
200 		     FE_INVALID | FE_DIVBYZERO, 0, 1);
201 		test(cexpf, CMPLXL(finites[i], 0.0),
202 		     CMPLXL(expf(finites[i]), 0.0),
203 		     FE_INVALID | FE_DIVBYZERO, 0, 1);
204 		test(cexpf, CMPLXL(finites[i], -0.0),
205 		     CMPLXL(expf(finites[i]), -0.0),
206 		     FE_INVALID | FE_DIVBYZERO, 0, 1);
207 	}
208 }
209 
210 static void
211 test_imaginaries(void)
212 {
213 	unsigned i;
214 
215 	for (i = 0; i < nitems(finites); i++) {
216 		printf("# Run %d..\n", i);
217 		test(cexp, CMPLXL(0.0, finites[i]),
218 		     CMPLXL(cos(finites[i]), sin(finites[i])),
219 		     ALL_STD_EXCEPT & ~FE_INEXACT, 0, 1);
220 		test(cexp, CMPLXL(-0.0, finites[i]),
221 		     CMPLXL(cos(finites[i]), sin(finites[i])),
222 		     ALL_STD_EXCEPT & ~FE_INEXACT, 0, 1);
223 		test(cexpf, CMPLXL(0.0, finites[i]),
224 		     CMPLXL(cosf(finites[i]), sinf(finites[i])),
225 		     ALL_STD_EXCEPT & ~FE_INEXACT, 0, 1);
226 		test(cexpf, CMPLXL(-0.0, finites[i]),
227 		     CMPLXL(cosf(finites[i]), sinf(finites[i])),
228 		     ALL_STD_EXCEPT & ~FE_INEXACT, 0, 1);
229 	}
230 }
231 
232 static void
233 test_small(void)
234 {
235 	static const double tests[] = {
236 	     /* csqrt(a + bI) = x + yI */
237 	     /* a	b	x			y */
238 		 1.0,	M_PI_4,	M_SQRT2 * 0.5 * M_E,	M_SQRT2 * 0.5 * M_E,
239 		-1.0,	M_PI_4,	M_SQRT2 * 0.5 / M_E,	M_SQRT2 * 0.5 / M_E,
240 		 2.0,	M_PI_2,	0.0,			M_E * M_E,
241 		 M_LN2,	M_PI,	-2.0,			0.0,
242 	};
243 	double a, b;
244 	double x, y;
245 	unsigned i;
246 
247 	for (i = 0; i < nitems(tests); i += 4) {
248 		printf("# Run %d..\n", i);
249 		a = tests[i];
250 		b = tests[i + 1];
251 		x = tests[i + 2];
252 		y = tests[i + 3];
253 		test_tol(cexp, CMPLXL(a, b), CMPLXL(x, y), 3 * DBL_ULP());
254 
255 		/* float doesn't have enough precision to pass these tests */
256 		if (x == 0 || y == 0)
257 			continue;
258 		test_tol(cexpf, CMPLXL(a, b), CMPLXL(x, y), 1 * FLT_ULP());
259         }
260 }
261 
262 /* Test inputs with a real part r that would overflow exp(r). */
263 static void
264 test_large(void)
265 {
266 
267 	test_tol(cexp, CMPLXL(709.79, 0x1p-1074),
268 		 CMPLXL(INFINITY, 8.94674309915433533273e-16), DBL_ULP());
269 	test_tol(cexp, CMPLXL(1000, 0x1p-1074),
270 		 CMPLXL(INFINITY, 9.73344457300016401328e+110), DBL_ULP());
271 	test_tol(cexp, CMPLXL(1400, 0x1p-1074),
272 		 CMPLXL(INFINITY, 5.08228858149196559681e+284), DBL_ULP());
273 	test_tol(cexp, CMPLXL(900, 0x1.23456789abcdep-1020),
274 		 CMPLXL(INFINITY, 7.42156649354218408074e+83), DBL_ULP());
275 	test_tol(cexp, CMPLXL(1300, 0x1.23456789abcdep-1020),
276 		 CMPLXL(INFINITY, 3.87514844965996756704e+257), DBL_ULP());
277 
278 	test_tol(cexpf, CMPLXL(88.73, 0x1p-149),
279 		 CMPLXL(INFINITY, 4.80265603e-07), 2 * FLT_ULP());
280 	test_tol(cexpf, CMPLXL(90, 0x1p-149),
281 		 CMPLXL(INFINITY, 1.7101492622e-06f), 2 * FLT_ULP());
282 	test_tol(cexpf, CMPLXL(192, 0x1p-149),
283 		 CMPLXL(INFINITY, 3.396809344e+38f), 2 * FLT_ULP());
284 	test_tol(cexpf, CMPLXL(120, 0x1.234568p-120),
285 		 CMPLXL(INFINITY, 1.1163382522e+16f), 2 * FLT_ULP());
286 	test_tol(cexpf, CMPLXL(170, 0x1.234568p-120),
287 		 CMPLXL(INFINITY, 5.7878851079e+37f), 2 * FLT_ULP());
288 }
289 
290 int
291 main(void)
292 {
293 
294 	printf("1..7\n");
295 
296 	test_zero();
297 	printf("ok 1 - cexp zero\n");
298 
299 	test_nan();
300 	printf("ok 2 - cexp nan\n");
301 
302 	test_inf();
303 	printf("ok 3 - cexp inf\n");
304 
305 #if defined(__i386__)
306 	printf("not ok 4 - cexp reals # TODO: PR # 191676 fails assertion on i386\n");
307 #else
308 	test_reals();
309 	printf("ok 4 - cexp reals\n");
310 #endif
311 
312 	test_imaginaries();
313 	printf("ok 5 - cexp imaginaries\n");
314 
315 	test_small();
316 	printf("ok 6 - cexp small\n");
317 
318 	test_large();
319 	printf("ok 7 - cexp large\n");
320 
321 	return (0);
322 }
323