xref: /freebsd/lib/msun/tests/next_test.c (revision 3416500aef140042c64bc149cb1ec6620483bc44)
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 int
76 main(void)
77 {
78 	static const int ex_under = FE_UNDERFLOW | FE_INEXACT;	/* shorthand */
79 	static const int ex_over = FE_OVERFLOW | FE_INEXACT;
80 	long double ldbl_small, ldbl_eps, ldbl_max;
81 
82 	printf("1..5\n");
83 
84 #ifdef	__i386__
85 	fpsetprec(FP_PE);
86 #endif
87 	/*
88 	 * We can't use a compile-time constant here because gcc on
89 	 * FreeBSD/i386 assumes long doubles are truncated to the
90 	 * double format.
91 	 */
92 	ldbl_small = ldexpl(1.0, LDBL_MIN_EXP - LDBL_MANT_DIG);
93 	ldbl_eps = LDBL_EPSILON;
94 	ldbl_max = ldexpl(1.0 - ldbl_eps / 2, LDBL_MAX_EXP);
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 	printf("ok 1 - next\n");
125 
126 	/*
127 	 * `x == y' and NaN tests
128 	 */
129 	testall(42.0, 42.0, 42.0, 0);
130 	testall(-42.0, -42.0, -42.0, 0);
131 	testall(INFINITY, INFINITY, INFINITY, 0);
132 	testall(-INFINITY, -INFINITY, -INFINITY, 0);
133 	testall(NAN, 42.0, NAN, 0);
134 	testall(42.0, NAN, NAN, 0);
135 	testall(NAN, NAN, NAN, 0);
136 
137 	printf("ok 2 - next\n");
138 
139 	/*
140 	 * Tests where x is an ordinary normalized number
141 	 */
142 	testboth(1.0, 2.0, 1.0 + DBL_EPSILON, 0, );
143 	testboth(1.0, -INFINITY, 1.0 - DBL_EPSILON/2, 0, );
144 	testboth(1.0, 2.0, 1.0 + FLT_EPSILON, 0, f);
145 	testboth(1.0, -INFINITY, 1.0 - FLT_EPSILON/2, 0, f);
146 	testboth(1.0, 2.0, 1.0 + ldbl_eps, 0, l);
147 	testboth(1.0, -INFINITY, 1.0 - ldbl_eps/2, 0, l);
148 
149 	testboth(-1.0, 2.0, -1.0 + DBL_EPSILON/2, 0, );
150 	testboth(-1.0, -INFINITY, -1.0 - DBL_EPSILON, 0, );
151 	testboth(-1.0, 2.0, -1.0 + FLT_EPSILON/2, 0, f);
152 	testboth(-1.0, -INFINITY, -1.0 - FLT_EPSILON, 0, f);
153 	testboth(-1.0, 2.0, -1.0 + ldbl_eps/2, 0, l);
154 	testboth(-1.0, -INFINITY, -1.0 - ldbl_eps, 0, l);
155 
156 	/* Cases where nextafter(...) != nexttoward(...) */
157 	test(nexttoward(1.0, 1.0 + ldbl_eps), 1.0 + DBL_EPSILON, 0);
158 	testf(nexttowardf(1.0, 1.0 + ldbl_eps), 1.0 + FLT_EPSILON, 0);
159 	testl(nexttowardl(1.0, 1.0 + ldbl_eps), 1.0 + ldbl_eps, 0);
160 
161 	printf("ok 3 - next\n");
162 
163 	/*
164 	 * Tests at word boundaries, normalization boundaries, etc.
165 	 */
166 	testboth(0x1.87654ffffffffp+0, INFINITY, 0x1.87655p+0, 0, );
167 	testboth(0x1.87655p+0, -INFINITY, 0x1.87654ffffffffp+0, 0, );
168 	testboth(0x1.fffffffffffffp+0, INFINITY, 0x1p1, 0, );
169 	testboth(0x1p1, -INFINITY, 0x1.fffffffffffffp+0, 0, );
170 	testboth(0x0.fffffffffffffp-1022, INFINITY, 0x1p-1022, 0, );
171 	testboth(0x1p-1022, -INFINITY, 0x0.fffffffffffffp-1022, ex_under, );
172 
173 	testboth(0x1.fffffep0f, INFINITY, 0x1p1, 0, f);
174 	testboth(0x1p1, -INFINITY, 0x1.fffffep0f, 0, f);
175 	testboth(0x0.fffffep-126f, INFINITY, 0x1p-126f, 0, f);
176 	testboth(0x1p-126f, -INFINITY, 0x0.fffffep-126f, ex_under, f);
177 
178 #if LDBL_MANT_DIG == 53
179 	testboth(0x1.87654ffffffffp+0L, INFINITY, 0x1.87655p+0L, 0, l);
180 	testboth(0x1.87655p+0L, -INFINITY, 0x1.87654ffffffffp+0L, 0, l);
181 	testboth(0x1.fffffffffffffp+0L, INFINITY, 0x1p1L, 0, l);
182 	testboth(0x1p1L, -INFINITY, 0x1.fffffffffffffp+0L, 0, l);
183 	testboth(0x0.fffffffffffffp-1022L, INFINITY, 0x1p-1022L, 0, l);
184 	testboth(0x1p-1022L, -INFINITY, 0x0.fffffffffffffp-1022L, ex_under, l);
185 #elif LDBL_MANT_DIG == 64 && !defined(__i386)
186 	testboth(0x1.87654321fffffffep+0L, INFINITY, 0x1.87654322p+0L, 0, l);
187 	testboth(0x1.87654322p+0L, -INFINITY, 0x1.87654321fffffffep+0L, 0, l);
188 	testboth(0x1.fffffffffffffffep0L, INFINITY, 0x1p1L, 0, l);
189 	testboth(0x1p1L, -INFINITY, 0x1.fffffffffffffffep0L, 0, l);
190 	testboth(0x0.fffffffffffffffep-16382L, INFINITY, 0x1p-16382L, 0, l);
191 	testboth(0x1p-16382L, -INFINITY,
192 	    0x0.fffffffffffffffep-16382L, ex_under, l);
193 #elif LDBL_MANT_DIG == 113
194 	testboth(0x1.876543210987ffffffffffffffffp+0L, INFINITY,
195 	    0x1.876543210988p+0, 0, l);
196 	testboth(0x1.876543210988p+0L, -INFINITY,
197 	    0x1.876543210987ffffffffffffffffp+0L, 0, l);
198 	testboth(0x1.ffffffffffffffffffffffffffffp0L, INFINITY, 0x1p1L, 0, l);
199 	testboth(0x1p1L, -INFINITY, 0x1.ffffffffffffffffffffffffffffp0L, 0, l);
200 	testboth(0x0.ffffffffffffffffffffffffffffp-16382L, INFINITY,
201 	    0x1p-16382L, 0, l);
202 	testboth(0x1p-16382L, -INFINITY,
203 	    0x0.ffffffffffffffffffffffffffffp-16382L, ex_under, l);
204 #endif
205 
206 	printf("ok 4 - next\n");
207 
208 	/*
209 	 * Overflow tests
210 	 */
211 	test(idd(nextafter(DBL_MAX, INFINITY)), INFINITY, ex_over);
212 	test(idd(nextafter(INFINITY, 0.0)), DBL_MAX, 0);
213 	test(idd(nexttoward(DBL_MAX, DBL_MAX * 2.0L)), INFINITY, ex_over);
214 #if LDBL_MANT_DIG > 53
215 	test(idd(nexttoward(INFINITY, DBL_MAX * 2.0L)), DBL_MAX, 0);
216 #endif
217 
218 	testf(idf(nextafterf(FLT_MAX, INFINITY)), INFINITY, ex_over);
219 	testf(idf(nextafterf(INFINITY, 0.0)), FLT_MAX, 0);
220 	testf(idf(nexttowardf(FLT_MAX, FLT_MAX * 2.0)), INFINITY, ex_over);
221 	testf(idf(nexttowardf(INFINITY, FLT_MAX * 2.0)), FLT_MAX, 0);
222 
223 	testboth(ldbl_max, INFINITY, INFINITY, ex_over, l);
224 	testboth(INFINITY, 0.0, ldbl_max, 0, l);
225 
226 	printf("ok 5 - next\n");
227 
228 	return (0);
229 }
230 
231 static void
232 _testl(const char *exp, int line, long double actual, long double expected,
233     int except)
234 {
235 	int actual_except;
236 
237 	actual_except = fetestexcept(ALL_STD_EXCEPT);
238 	if (!fpequal(actual, expected)) {
239 		fprintf(stderr, "%d: %s returned %La, expecting %La\n",
240 		    line, exp, actual, expected);
241 		abort();
242 	}
243 	if (actual_except != except) {
244 		fprintf(stderr, "%d: %s raised 0x%x, expecting 0x%x\n",
245 		    line, exp, actual_except, except);
246 		abort();
247 	}
248 }
249 
250 /*
251  * The idd() and idf() routines ensure that doubles and floats are
252  * converted to their respective types instead of stored in the FPU
253  * with extra precision.
254  */
255 static double
256 idd(double x)
257 {
258 	return (x);
259 }
260 
261 static float
262 idf(float x)
263 {
264 	return (x);
265 }
266