xref: /freebsd/lib/msun/tests/next_test.c (revision d7d962ead0b6e5e8a39202d0590022082bf5bfb6)
1 /*-
2  * Copyright (c) 2005 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  * Test the correctness of nextafter{,f,l} and nexttoward{,f,l}.
29  */
30 
31 #include <sys/cdefs.h>
32 __FBSDID("$FreeBSD$");
33 
34 #include <fenv.h>
35 #include <float.h>
36 #include <math.h>
37 #include <stdio.h>
38 #include <stdlib.h>
39 
40 #ifdef	__i386__
41 #include <ieeefp.h>
42 #endif
43 
44 #include "test-utils.h"
45 
46 #define	test(exp, ans, ex)	do {			\
47 	double __ans = (ans);				\
48 	feclearexcept(ALL_STD_EXCEPT);			\
49 	_testl(#exp, __LINE__, (exp), __ans, (ex));	\
50 } while (0)
51 #define	testf(exp, ans, ex)	do {			\
52 	float __ans = (ans);				\
53 	feclearexcept(ALL_STD_EXCEPT);			\
54 	_testl(#exp, __LINE__, (exp), __ans, (ex));	\
55 } while (0)
56 #define	testl(exp, ans, ex)	do {			\
57 	long double __ans = (ans);			\
58 	feclearexcept(ALL_STD_EXCEPT);			\
59 	_testl(#exp, __LINE__, (exp), __ans, (ex));	\
60 } while (0)
61 #define	testboth(arg1, arg2, ans, ex, prec)	do {			\
62 	test##prec(nextafter##prec((arg1), (arg2)), (ans), (ex));	\
63 	test##prec(nexttoward##prec((arg1), (arg2)), (ans), (ex));	\
64 } while (0)
65 #define	testall(arg1, arg2, ans, ex)	do {		\
66 	testboth((arg1), (arg2), (ans), (ex), );	\
67 	testboth((arg1), (arg2), (ans), (ex), f);	\
68 	testboth((arg1), (arg2), (ans), (ex), l);	\
69 } while (0)
70 
71 static void _testl(const char *, int, long double, long double, int);
72 static double idd(double);
73 static float idf(float);
74 
75 static const int ex_under = FE_UNDERFLOW | FE_INEXACT;	/* shorthand */
76 static const int ex_over = FE_OVERFLOW | FE_INEXACT;
77 static const long double ldbl_eps = LDBL_EPSILON;
78 
79 
80 
81 ATF_TC_WITHOUT_HEAD(zeros);
82 ATF_TC_BODY(zeros, tc)
83 {
84 	long double ldbl_small;
85 
86 #ifdef	__i386__
87 	fpsetprec(FP_PE);
88 #endif
89 	/*
90 	 * We can't use a compile-time constant here because gcc on
91 	 * FreeBSD/i386 assumes long doubles are truncated to the
92 	 * double format.
93 	 */
94 	ldbl_small = ldexpl(1.0, LDBL_MIN_EXP - LDBL_MANT_DIG);
95 
96 	/*
97 	 * Special cases involving zeroes.
98 	 */
99 #define	ztest(prec)							      \
100 	test##prec(copysign##prec(1.0, nextafter##prec(0.0, -0.0)), -1.0, 0); \
101 	test##prec(copysign##prec(1.0, nextafter##prec(-0.0, 0.0)), 1.0, 0);  \
102 	test##prec(copysign##prec(1.0, nexttoward##prec(0.0, -0.0)), -1.0, 0);\
103 	test##prec(copysign##prec(1.0, nexttoward##prec(-0.0, 0.0)), 1.0, 0)
104 
105 	ztest();
106 	ztest(f);
107 	ztest(l);
108 #undef	ztest
109 
110 #define	stest(next, eps, prec)					\
111 	test##prec(next(-0.0, 42.0), eps, ex_under);		\
112 	test##prec(next(0.0, -42.0), -eps, ex_under);		\
113 	test##prec(next(0.0, INFINITY), eps, ex_under);		\
114 	test##prec(next(-0.0, -INFINITY), -eps, ex_under)
115 
116 	stest(nextafter, 0x1p-1074, );
117 	stest(nextafterf, 0x1p-149f, f);
118 	stest(nextafterl, ldbl_small, l);
119 	stest(nexttoward, 0x1p-1074, );
120 	stest(nexttowardf, 0x1p-149f, f);
121 	stest(nexttowardl, ldbl_small, l);
122 #undef	stest
123 }
124 
125 ATF_TC_WITHOUT_HEAD(eq_and_nan);
126 ATF_TC_BODY(eq_and_nan, tc)
127 {
128 	/*
129 	 * `x == y' and NaN tests
130 	 */
131 	testall(42.0, 42.0, 42.0, 0);
132 	testall(-42.0, -42.0, -42.0, 0);
133 	testall(INFINITY, INFINITY, INFINITY, 0);
134 	testall(-INFINITY, -INFINITY, -INFINITY, 0);
135 	testall(NAN, 42.0, NAN, 0);
136 	testall(42.0, NAN, NAN, 0);
137 	testall(NAN, NAN, NAN, 0);
138 }
139 
140 ATF_TC_WITHOUT_HEAD(ordinary);
141 ATF_TC_BODY(ordinary, tc)
142 {
143 	/*
144 	 * Tests where x is an ordinary normalized number
145 	 */
146 	testboth(1.0, 2.0, 1.0 + DBL_EPSILON, 0, );
147 	testboth(1.0, -INFINITY, 1.0 - DBL_EPSILON / 2, 0, );
148 	testboth(1.0, 2.0, 1.0 + FLT_EPSILON, 0, f);
149 	testboth(1.0, -INFINITY, 1.0 - FLT_EPSILON / 2, 0, f);
150 	testboth(1.0, 2.0, 1.0 + ldbl_eps, 0, l);
151 	testboth(1.0, -INFINITY, 1.0 - ldbl_eps / 2, 0, l);
152 
153 	testboth(-1.0, 2.0, -1.0 + DBL_EPSILON / 2, 0, );
154 	testboth(-1.0, -INFINITY, -1.0 - DBL_EPSILON, 0, );
155 	testboth(-1.0, 2.0, -1.0 + FLT_EPSILON / 2, 0, f);
156 	testboth(-1.0, -INFINITY, -1.0 - FLT_EPSILON, 0, f);
157 	testboth(-1.0, 2.0, -1.0 + ldbl_eps / 2, 0, l);
158 	testboth(-1.0, -INFINITY, -1.0 - ldbl_eps, 0, l);
159 
160 	/* Cases where nextafter(...) != nexttoward(...) */
161 	test(nexttoward(1.0, 1.0 + ldbl_eps), 1.0 + DBL_EPSILON, 0);
162 	testf(nexttowardf(1.0, 1.0 + ldbl_eps), 1.0 + FLT_EPSILON, 0);
163 	testl(nexttowardl(1.0, 1.0 + ldbl_eps), 1.0 + ldbl_eps, 0);
164 }
165 
166 ATF_TC_WITHOUT_HEAD(boundaries);
167 ATF_TC_BODY(boundaries, tc)
168 {
169 	/*
170 	 * Tests at word boundaries, normalization boundaries, etc.
171 	 */
172 	testboth(0x1.87654ffffffffp+0, INFINITY, 0x1.87655p+0, 0, );
173 	testboth(0x1.87655p+0, -INFINITY, 0x1.87654ffffffffp+0, 0, );
174 	testboth(0x1.fffffffffffffp+0, INFINITY, 0x1p1, 0, );
175 	testboth(0x1p1, -INFINITY, 0x1.fffffffffffffp+0, 0, );
176 	testboth(0x0.fffffffffffffp-1022, INFINITY, 0x1p-1022, 0, );
177 	testboth(0x1p-1022, -INFINITY, 0x0.fffffffffffffp-1022, ex_under, );
178 
179 	testboth(0x1.fffffep0f, INFINITY, 0x1p1, 0, f);
180 	testboth(0x1p1, -INFINITY, 0x1.fffffep0f, 0, f);
181 	testboth(0x0.fffffep-126f, INFINITY, 0x1p-126f, 0, f);
182 	testboth(0x1p-126f, -INFINITY, 0x0.fffffep-126f, ex_under, f);
183 
184 #if LDBL_MANT_DIG == 53
185 	testboth(0x1.87654ffffffffp+0L, INFINITY, 0x1.87655p+0L, 0, l);
186 	testboth(0x1.87655p+0L, -INFINITY, 0x1.87654ffffffffp+0L, 0, l);
187 	testboth(0x1.fffffffffffffp+0L, INFINITY, 0x1p1L, 0, l);
188 	testboth(0x1p1L, -INFINITY, 0x1.fffffffffffffp+0L, 0, l);
189 	testboth(0x0.fffffffffffffp-1022L, INFINITY, 0x1p-1022L, 0, l);
190 	testboth(0x1p-1022L, -INFINITY, 0x0.fffffffffffffp-1022L, ex_under, l);
191 #elif LDBL_MANT_DIG == 64 && !defined(__i386)
192 	testboth(0x1.87654321fffffffep+0L, INFINITY, 0x1.87654322p+0L, 0, l);
193 	testboth(0x1.87654322p+0L, -INFINITY, 0x1.87654321fffffffep+0L, 0, l);
194 	testboth(0x1.fffffffffffffffep0L, INFINITY, 0x1p1L, 0, l);
195 	testboth(0x1p1L, -INFINITY, 0x1.fffffffffffffffep0L, 0, l);
196 	testboth(0x0.fffffffffffffffep-16382L, INFINITY, 0x1p-16382L, 0, l);
197 	testboth(0x1p-16382L, -INFINITY,
198 	    0x0.fffffffffffffffep-16382L, ex_under, l);
199 #elif LDBL_MANT_DIG == 113
200 	testboth(0x1.876543210987ffffffffffffffffp+0L, INFINITY,
201 	    0x1.876543210988p+0, 0, l);
202 	testboth(0x1.876543210988p+0L, -INFINITY,
203 	    0x1.876543210987ffffffffffffffffp+0L, 0, l);
204 	testboth(0x1.ffffffffffffffffffffffffffffp0L, INFINITY, 0x1p1L, 0, l);
205 	testboth(0x1p1L, -INFINITY, 0x1.ffffffffffffffffffffffffffffp0L, 0, l);
206 	testboth(0x0.ffffffffffffffffffffffffffffp-16382L, INFINITY,
207 	    0x1p-16382L, 0, l);
208 	testboth(0x1p-16382L, -INFINITY,
209 	    0x0.ffffffffffffffffffffffffffffp-16382L, ex_under, l);
210 #endif
211 }
212 
213 ATF_TC_WITHOUT_HEAD(overflow);
214 ATF_TC_BODY(overflow, tc)
215 {
216 	long double ldbl_max;
217 	/*
218 	 * We can't use a compile-time constant here because gcc on
219 	 * FreeBSD/i386 assumes long doubles are truncated to the
220 	 * double format.
221 	 */
222 	ldbl_max = ldexpl(1.0 - ldbl_eps / 2, LDBL_MAX_EXP);
223 
224 	/*
225 	 * Overflow tests
226 	 */
227 	test(idd(nextafter(DBL_MAX, INFINITY)), INFINITY, ex_over);
228 	test(idd(nextafter(INFINITY, 0.0)), DBL_MAX, 0);
229 	test(idd(nexttoward(DBL_MAX, DBL_MAX * 2.0L)), INFINITY, ex_over);
230 #if LDBL_MANT_DIG > 53
231 	test(idd(nexttoward(INFINITY, DBL_MAX * 2.0L)), DBL_MAX, 0);
232 #endif
233 
234 	testf(idf(nextafterf(FLT_MAX, INFINITY)), INFINITY, ex_over);
235 	testf(idf(nextafterf(INFINITY, 0.0)), FLT_MAX, 0);
236 	testf(idf(nexttowardf(FLT_MAX, FLT_MAX * 2.0)), INFINITY, ex_over);
237 	testf(idf(nexttowardf(INFINITY, FLT_MAX * 2.0)), FLT_MAX, 0);
238 
239 	testboth(ldbl_max, INFINITY, INFINITY, ex_over, l);
240 	testboth(INFINITY, 0.0, ldbl_max, 0, l);
241 }
242 
243 static void
244 _testl(const char *exp, int line, long double actual, long double expected,
245     int except)
246 {
247 	int actual_except;
248 
249 	actual_except = fetestexcept(ALL_STD_EXCEPT);
250 	if (!fpequal_cs(actual, expected, true)) {
251 		atf_tc_fail_check(__FILE__, line,
252 		    "%s returned %La, expecting %La\n", exp, actual, expected);
253 	}
254 	if (actual_except != except) {
255 		atf_tc_fail_check(__FILE__, line,
256 		    "%s raised 0x%x, expecting 0x%x\n", exp, actual_except,
257 		    except);
258 	}
259 }
260 
261 /*
262  * The idd() and idf() routines ensure that doubles and floats are
263  * converted to their respective types instead of stored in the FPU
264  * with extra precision.
265  */
266 static double
267 idd(double x)
268 {
269 	return (x);
270 }
271 
272 static float
273 idf(float x)
274 {
275 	return (x);
276 }
277 
278 ATF_TP_ADD_TCS(tp)
279 {
280 	ATF_TP_ADD_TC(tp, zeros);
281 	ATF_TP_ADD_TC(tp, ordinary);
282 	ATF_TP_ADD_TC(tp, eq_and_nan);
283 	ATF_TP_ADD_TC(tp, boundaries);
284 	ATF_TP_ADD_TC(tp, overflow);
285 
286 	return (atf_no_error());
287 }
288