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: stable/9/tools/regression/lib/msun/test-cexp.c 292806 2015-12-27 21:55:26Z ngie $");
33 
34 #include <assert.h>
35 #include <complex.h>
36 #include <fenv.h>
37 #include <float.h>
38 #include <math.h>
39 #include <stdio.h>
40 
41 #define	ALL_STD_EXCEPT	(FE_DIVBYZERO | FE_INEXACT | FE_INVALID | \
42 			 FE_OVERFLOW | FE_UNDERFLOW)
43 #define	FLT_ULP()	ldexpl(1.0, 1 - FLT_MANT_DIG)
44 #define	DBL_ULP()	ldexpl(1.0, 1 - DBL_MANT_DIG)
45 #define	LDBL_ULP()	ldexpl(1.0, 1 - LDBL_MANT_DIG)
46 
47 #define	N(i)	(sizeof(i) / sizeof((i)[0]))
48 
49 #pragma STDC FENV_ACCESS	ON
50 #pragma	STDC CX_LIMITED_RANGE	OFF
51 
52 /*
53  * XXX gcc implements complex multiplication incorrectly. In
54  * particular, it implements it as if the CX_LIMITED_RANGE pragma
55  * were ON. Consequently, we need this function to form numbers
56  * such as x + INFINITY * I, since gcc evalutes INFINITY * I as
57  * NaN + INFINITY * I.
58  */
59 static inline long double complex
cpackl(long double x,long double y)60 cpackl(long double x, long double y)
61 {
62 	long double complex z;
63 
64 	__real__ z = x;
65 	__imag__ z = y;
66 	return (z);
67 }
68 
69 /*
70  * Test that a function returns the correct value and sets the
71  * exception flags correctly. The exceptmask specifies which
72  * exceptions we should check. We need to be lenient for several
73  * reasons, but mainly because on some architectures it's impossible
74  * to raise FE_OVERFLOW without raising FE_INEXACT. In some cases,
75  * whether cexp() raises an invalid exception is unspecified.
76  *
77  * These are macros instead of functions so that assert provides more
78  * meaningful error messages.
79  *
80  * XXX The volatile here is to avoid gcc's bogus constant folding and work
81  *     around the lack of support for the FENV_ACCESS pragma.
82  */
83 #define	test(func, z, result, exceptmask, excepts, checksign)	do {	\
84 	volatile long double complex _d = z;				\
85 	assert(feclearexcept(FE_ALL_EXCEPT) == 0);			\
86 	assert(cfpequal((func)(_d), (result), (checksign)));		\
87 	assert(((func), fetestexcept(exceptmask) == (excepts)));	\
88 } while (0)
89 
90 /* Test within a given tolerance. */
91 #define	test_tol(func, z, result, tol)				do {	\
92 	volatile long double complex _d = z;				\
93 	assert(cfpequal_tol((func)(_d), (result), (tol)));		\
94 } while (0)
95 
96 /* Test all the functions that compute cexp(x). */
97 #define	testall(x, result, exceptmask, excepts, checksign)	do {	\
98 	test(cexp, x, result, exceptmask, excepts, checksign);		\
99 	test(cexpf, x, result, exceptmask, excepts, checksign);		\
100 } while (0)
101 
102 /*
103  * Test all the functions that compute cexp(x), within a given tolerance.
104  * The tolerance is specified in ulps.
105  */
106 #define	testall_tol(x, result, tol)				do {	\
107 	test_tol(cexp, x, result, tol * DBL_ULP());			\
108 	test_tol(cexpf, x, result, tol * FLT_ULP());			\
109 } while (0)
110 
111 /* Various finite non-zero numbers to test. */
112 static const float finites[] =
113 { -42.0e20, -1.0, -1.0e-10, -0.0, 0.0, 1.0e-10, 1.0, 42.0e20 };
114 
115 /*
116  * Determine whether x and y are equal, with two special rules:
117  *	+0.0 != -0.0
118  *	 NaN == NaN
119  * If checksign is 0, we compare the absolute values instead.
120  */
121 static int
fpequal(long double x,long double y,int checksign)122 fpequal(long double x, long double y, int checksign)
123 {
124 	if (isnan(x) || isnan(y))
125 		return (1);
126 	if (checksign)
127 		return (x == y && !signbit(x) == !signbit(y));
128 	else
129 		return (fabsl(x) == fabsl(y));
130 }
131 
132 static int
fpequal_tol(long double x,long double y,long double tol)133 fpequal_tol(long double x, long double y, long double tol)
134 {
135 	fenv_t env;
136 	int ret;
137 
138 	if (isnan(x) && isnan(y))
139 		return (1);
140 	if (!signbit(x) != !signbit(y))
141 		return (0);
142 	if (x == y)
143 		return (1);
144 	if (tol == 0)
145 		return (0);
146 
147 	/* Hard case: need to check the tolerance. */
148 	feholdexcept(&env);
149 	/*
150 	 * For our purposes here, if y=0, we interpret tol as an absolute
151 	 * tolerance. This is to account for roundoff in the input, e.g.,
152 	 * cos(Pi/2) ~= 0.
153 	 */
154 	if (y == 0.0)
155 		ret = fabsl(x - y) <= fabsl(tol);
156 	else
157 		ret = fabsl(x - y) <= fabsl(y * tol);
158 	fesetenv(&env);
159 	return (ret);
160 }
161 
162 static int
cfpequal(long double complex x,long double complex y,int checksign)163 cfpequal(long double complex x, long double complex y, int checksign)
164 {
165 	return (fpequal(creal(x), creal(y), checksign)
166 		&& fpequal(cimag(x), cimag(y), checksign));
167 }
168 
169 static int
cfpequal_tol(long double complex x,long double complex y,long double tol)170 cfpequal_tol(long double complex x, long double complex y, long double tol)
171 {
172 	return (fpequal_tol(creal(x), creal(y), tol)
173 		&& fpequal_tol(cimag(x), cimag(y), tol));
174 }
175 
176 
177 /* Tests for 0 */
178 void
test_zero(void)179 test_zero(void)
180 {
181 
182 	/* cexp(0) = 1, no exceptions raised */
183 	testall(0.0, 1.0, ALL_STD_EXCEPT, 0, 1);
184 	testall(-0.0, 1.0, ALL_STD_EXCEPT, 0, 1);
185 	testall(cpackl(0.0, -0.0), cpackl(1.0, -0.0), ALL_STD_EXCEPT, 0, 1);
186 	testall(cpackl(-0.0, -0.0), cpackl(1.0, -0.0), ALL_STD_EXCEPT, 0, 1);
187 }
188 
189 /*
190  * Tests for NaN.  The signs of the results are indeterminate unless the
191  * imaginary part is 0.
192  */
193 void
test_nan()194 test_nan()
195 {
196 	int i;
197 
198 	/* cexp(x + NaNi) = NaN + NaNi and optionally raises invalid */
199 	/* cexp(NaN + yi) = NaN + NaNi and optionally raises invalid (|y|>0) */
200 	for (i = 0; i < N(finites); i++) {
201 		testall(cpackl(finites[i], NAN), cpackl(NAN, NAN),
202 			ALL_STD_EXCEPT & ~FE_INVALID, 0, 0);
203 		if (finites[i] == 0.0)
204 			continue;
205 		/* XXX FE_INEXACT shouldn't be raised here */
206 		testall(cpackl(NAN, finites[i]), cpackl(NAN, NAN),
207 			ALL_STD_EXCEPT & ~(FE_INVALID | FE_INEXACT), 0, 0);
208 	}
209 
210 	/* cexp(NaN +- 0i) = NaN +- 0i */
211 	testall(cpackl(NAN, 0.0), cpackl(NAN, 0.0), ALL_STD_EXCEPT, 0, 1);
212 	testall(cpackl(NAN, -0.0), cpackl(NAN, -0.0), ALL_STD_EXCEPT, 0, 1);
213 
214 	/* cexp(inf + NaN i) = inf + nan i */
215 	testall(cpackl(INFINITY, NAN), cpackl(INFINITY, NAN),
216 		ALL_STD_EXCEPT, 0, 0);
217 	/* cexp(-inf + NaN i) = 0 */
218 	testall(cpackl(-INFINITY, NAN), cpackl(0.0, 0.0),
219 		ALL_STD_EXCEPT, 0, 0);
220 	/* cexp(NaN + NaN i) = NaN + NaN i */
221 	testall(cpackl(NAN, NAN), cpackl(NAN, NAN),
222 		ALL_STD_EXCEPT, 0, 0);
223 }
224 
225 void
test_inf(void)226 test_inf(void)
227 {
228 	int i;
229 
230 	/* cexp(x + inf i) = NaN + NaNi and raises invalid */
231 	for (i = 0; i < N(finites); i++) {
232 		testall(cpackl(finites[i], INFINITY), cpackl(NAN, NAN),
233 			ALL_STD_EXCEPT, FE_INVALID, 1);
234 	}
235 	/* cexp(-inf + yi) = 0 * (cos(y) + sin(y)i) */
236 	/* XXX shouldn't raise an inexact exception */
237 	testall(cpackl(-INFINITY, M_PI_4), cpackl(0.0, 0.0),
238 		ALL_STD_EXCEPT & ~FE_INEXACT, 0, 1);
239 	testall(cpackl(-INFINITY, 3 * M_PI_4), cpackl(-0.0, 0.0),
240 		ALL_STD_EXCEPT & ~FE_INEXACT, 0, 1);
241 	testall(cpackl(-INFINITY, 5 * M_PI_4), cpackl(-0.0, -0.0),
242 		ALL_STD_EXCEPT & ~FE_INEXACT, 0, 1);
243 	testall(cpackl(-INFINITY, 7 * M_PI_4), cpackl(0.0, -0.0),
244 		ALL_STD_EXCEPT & ~FE_INEXACT, 0, 1);
245 	testall(cpackl(-INFINITY, 0.0), cpackl(0.0, 0.0),
246 		ALL_STD_EXCEPT, 0, 1);
247 	testall(cpackl(-INFINITY, -0.0), cpackl(0.0, -0.0),
248 		ALL_STD_EXCEPT, 0, 1);
249 	/* cexp(inf + yi) = inf * (cos(y) + sin(y)i) (except y=0) */
250 	/* XXX shouldn't raise an inexact exception */
251 	testall(cpackl(INFINITY, M_PI_4), cpackl(INFINITY, INFINITY),
252 		ALL_STD_EXCEPT & ~FE_INEXACT, 0, 1);
253 	testall(cpackl(INFINITY, 3 * M_PI_4), cpackl(-INFINITY, INFINITY),
254 		ALL_STD_EXCEPT & ~FE_INEXACT, 0, 1);
255 	testall(cpackl(INFINITY, 5 * M_PI_4), cpackl(-INFINITY, -INFINITY),
256 		ALL_STD_EXCEPT & ~FE_INEXACT, 0, 1);
257 	testall(cpackl(INFINITY, 7 * M_PI_4), cpackl(INFINITY, -INFINITY),
258 		ALL_STD_EXCEPT & ~FE_INEXACT, 0, 1);
259 	/* cexp(inf + 0i) = inf + 0i */
260 	testall(cpackl(INFINITY, 0.0), cpackl(INFINITY, 0.0),
261 		ALL_STD_EXCEPT, 0, 1);
262 	testall(cpackl(INFINITY, -0.0), cpackl(INFINITY, -0.0),
263 		ALL_STD_EXCEPT, 0, 1);
264 }
265 
266 void
test_reals(void)267 test_reals(void)
268 {
269 	int i;
270 
271 	for (i = 0; i < N(finites); i++) {
272 		/* XXX could check exceptions more meticulously */
273 		test(cexp, cpackl(finites[i], 0.0),
274 		     cpackl(exp(finites[i]), 0.0),
275 		     FE_INVALID | FE_DIVBYZERO, 0, 1);
276 		test(cexp, cpackl(finites[i], -0.0),
277 		     cpackl(exp(finites[i]), -0.0),
278 		     FE_INVALID | FE_DIVBYZERO, 0, 1);
279 		test(cexpf, cpackl(finites[i], 0.0),
280 		     cpackl(expf(finites[i]), 0.0),
281 		     FE_INVALID | FE_DIVBYZERO, 0, 1);
282 		test(cexpf, cpackl(finites[i], -0.0),
283 		     cpackl(expf(finites[i]), -0.0),
284 		     FE_INVALID | FE_DIVBYZERO, 0, 1);
285 	}
286 }
287 
288 void
test_imaginaries(void)289 test_imaginaries(void)
290 {
291 	int i;
292 
293 	for (i = 0; i < N(finites); i++) {
294 		test(cexp, cpackl(0.0, finites[i]),
295 		     cpackl(cos(finites[i]), sin(finites[i])),
296 		     ALL_STD_EXCEPT & ~FE_INEXACT, 0, 1);
297 		test(cexp, cpackl(-0.0, finites[i]),
298 		     cpackl(cos(finites[i]), sin(finites[i])),
299 		     ALL_STD_EXCEPT & ~FE_INEXACT, 0, 1);
300 		test(cexpf, cpackl(0.0, finites[i]),
301 		     cpackl(cosf(finites[i]), sinf(finites[i])),
302 		     ALL_STD_EXCEPT & ~FE_INEXACT, 0, 1);
303 		test(cexpf, cpackl(-0.0, finites[i]),
304 		     cpackl(cosf(finites[i]), sinf(finites[i])),
305 		     ALL_STD_EXCEPT & ~FE_INEXACT, 0, 1);
306 	}
307 }
308 
309 void
test_small(void)310 test_small(void)
311 {
312 	static const double tests[] = {
313 	     /* csqrt(a + bI) = x + yI */
314 	     /* a	b	x			y */
315 		 1.0,	M_PI_4,	M_SQRT2 * 0.5 * M_E,	M_SQRT2 * 0.5 * M_E,
316 		-1.0,	M_PI_4,	M_SQRT2 * 0.5 / M_E,	M_SQRT2 * 0.5 / M_E,
317 		 2.0,	M_PI_2,	0.0,			M_E * M_E,
318 		 M_LN2,	M_PI,	-2.0,			0.0,
319 	};
320 	double a, b;
321 	double x, y;
322 	int i;
323 
324 	for (i = 0; i < N(tests); i += 4) {
325 		a = tests[i];
326 		b = tests[i + 1];
327 		x = tests[i + 2];
328 		y = tests[i + 3];
329 		test_tol(cexp, cpackl(a, b), cpackl(x, y), 3 * DBL_ULP());
330 
331 		/* float doesn't have enough precision to pass these tests */
332 		if (x == 0 || y == 0)
333 			continue;
334 		test_tol(cexpf, cpackl(a, b), cpackl(x, y), 1 * FLT_ULP());
335         }
336 }
337 
338 /* Test inputs with a real part r that would overflow exp(r). */
339 void
test_large(void)340 test_large(void)
341 {
342 
343 	test_tol(cexp, cpackl(709.79, 0x1p-1074),
344 		 cpackl(INFINITY, 8.94674309915433533273e-16), DBL_ULP());
345 	test_tol(cexp, cpackl(1000, 0x1p-1074),
346 		 cpackl(INFINITY, 9.73344457300016401328e+110), DBL_ULP());
347 	test_tol(cexp, cpackl(1400, 0x1p-1074),
348 		 cpackl(INFINITY, 5.08228858149196559681e+284), DBL_ULP());
349 	test_tol(cexp, cpackl(900, 0x1.23456789abcdep-1020),
350 		 cpackl(INFINITY, 7.42156649354218408074e+83), DBL_ULP());
351 	test_tol(cexp, cpackl(1300, 0x1.23456789abcdep-1020),
352 		 cpackl(INFINITY, 3.87514844965996756704e+257), DBL_ULP());
353 
354 	test_tol(cexpf, cpackl(88.73, 0x1p-149),
355 		 cpackl(INFINITY, 4.80265603e-07), 2 * FLT_ULP());
356 	test_tol(cexpf, cpackl(90, 0x1p-149),
357 		 cpackl(INFINITY, 1.7101492622e-06f), 2 * FLT_ULP());
358 	test_tol(cexpf, cpackl(192, 0x1p-149),
359 		 cpackl(INFINITY, 3.396809344e+38f), 2 * FLT_ULP());
360 	test_tol(cexpf, cpackl(120, 0x1.234568p-120),
361 		 cpackl(INFINITY, 1.1163382522e+16f), 2 * FLT_ULP());
362 	test_tol(cexpf, cpackl(170, 0x1.234568p-120),
363 		 cpackl(INFINITY, 5.7878851079e+37f), 2 * FLT_ULP());
364 }
365 
366 int
main(int argc,char * argv[])367 main(int argc, char *argv[])
368 {
369 
370 	printf("1..7\n");
371 
372 	test_zero();
373 	printf("ok 1 - cexp zero\n");
374 
375 	test_nan();
376 	printf("ok 2 - cexp nan\n");
377 
378 	test_inf();
379 	printf("ok 3 - cexp inf\n");
380 
381 	test_reals();
382 	printf("ok 4 - cexp reals\n");
383 
384 	test_imaginaries();
385 	printf("ok 5 - cexp imaginaries\n");
386 
387 	test_small();
388 	printf("ok 6 - cexp small\n");
389 
390 	test_large();
391 	printf("ok 7 - cexp large\n");
392 
393 	return (0);
394 }
395