1 /* $OpenBSD: next_test.c,v 1.2 2021/12/13 18:04:28 deraadt Exp $ */
2 /*-
3 * Copyright (c) 2005 David Schultz <das@FreeBSD.org>
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 */
27
28 #include "macros.h"
29
30 /*
31 * Test the correctness of nextafter{,f,l} and nexttoward{,f,l}.
32 */
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);
ATF_TC_BODY(zeros,tc)82 ATF_TC_BODY(zeros, tc)
83 {
84 long double ldbl_small;
85
86 #ifndef __OpenBSD__
87 #ifdef __i386__
88 fpsetprec(FP_PE);
89 #endif
90 #endif
91 /*
92 * We can't use a compile-time constant here because gcc on
93 * FreeBSD/i386 assumes long doubles are truncated to the
94 * double format.
95 */
96 ldbl_small = ldexpl(1.0, LDBL_MIN_EXP - LDBL_MANT_DIG);
97
98 /*
99 * Special cases involving zeroes.
100 */
101 #define ztest(prec) \
102 test##prec(copysign##prec(1.0, nextafter##prec(0.0, -0.0)), -1.0, 0); \
103 test##prec(copysign##prec(1.0, nextafter##prec(-0.0, 0.0)), 1.0, 0); \
104 test##prec(copysign##prec(1.0, nexttoward##prec(0.0, -0.0)), -1.0, 0);\
105 test##prec(copysign##prec(1.0, nexttoward##prec(-0.0, 0.0)), 1.0, 0)
106
107 ztest();
108 ztest(f);
109 ztest(l);
110 #undef ztest
111
112 #define stest(next, eps, prec) \
113 test##prec(next(-0.0, 42.0), eps, ex_under); \
114 test##prec(next(0.0, -42.0), -eps, ex_under); \
115 test##prec(next(0.0, INFINITY), eps, ex_under); \
116 test##prec(next(-0.0, -INFINITY), -eps, ex_under)
117
118 stest(nextafter, 0x1p-1074, );
119 stest(nextafterf, 0x1p-149f, f);
120 stest(nextafterl, ldbl_small, l);
121 stest(nexttoward, 0x1p-1074, );
122 stest(nexttowardf, 0x1p-149f, f);
123 stest(nexttowardl, ldbl_small, l);
124 #undef stest
125 }
126
127 ATF_TC_WITHOUT_HEAD(eq_and_nan);
ATF_TC_BODY(eq_and_nan,tc)128 ATF_TC_BODY(eq_and_nan, tc)
129 {
130 /*
131 * `x == y' and NaN tests
132 */
133 testall(42.0, 42.0, 42.0, 0);
134 testall(-42.0, -42.0, -42.0, 0);
135 testall(INFINITY, INFINITY, INFINITY, 0);
136 testall(-INFINITY, -INFINITY, -INFINITY, 0);
137 testall(NAN, 42.0, NAN, 0);
138 testall(42.0, NAN, NAN, 0);
139 testall(NAN, NAN, NAN, 0);
140 }
141
142 ATF_TC_WITHOUT_HEAD(ordinary);
ATF_TC_BODY(ordinary,tc)143 ATF_TC_BODY(ordinary, tc)
144 {
145 /*
146 * Tests where x is an ordinary normalized number
147 */
148 testboth(1.0, 2.0, 1.0 + DBL_EPSILON, 0, );
149 testboth(1.0, -INFINITY, 1.0 - DBL_EPSILON / 2, 0, );
150 testboth(1.0, 2.0, 1.0 + FLT_EPSILON, 0, f);
151 testboth(1.0, -INFINITY, 1.0 - FLT_EPSILON / 2, 0, f);
152 testboth(1.0, 2.0, 1.0 + ldbl_eps, 0, l);
153 testboth(1.0, -INFINITY, 1.0 - ldbl_eps / 2, 0, l);
154
155 testboth(-1.0, 2.0, -1.0 + DBL_EPSILON / 2, 0, );
156 testboth(-1.0, -INFINITY, -1.0 - DBL_EPSILON, 0, );
157 testboth(-1.0, 2.0, -1.0 + FLT_EPSILON / 2, 0, f);
158 testboth(-1.0, -INFINITY, -1.0 - FLT_EPSILON, 0, f);
159 testboth(-1.0, 2.0, -1.0 + ldbl_eps / 2, 0, l);
160 testboth(-1.0, -INFINITY, -1.0 - ldbl_eps, 0, l);
161
162 /* Cases where nextafter(...) != nexttoward(...) */
163 test(nexttoward(1.0, 1.0 + ldbl_eps), 1.0 + DBL_EPSILON, 0);
164 testf(nexttowardf(1.0, 1.0 + ldbl_eps), 1.0 + FLT_EPSILON, 0);
165 testl(nexttowardl(1.0, 1.0 + ldbl_eps), 1.0 + ldbl_eps, 0);
166 }
167
168 ATF_TC_WITHOUT_HEAD(boundaries);
ATF_TC_BODY(boundaries,tc)169 ATF_TC_BODY(boundaries, tc)
170 {
171 /*
172 * Tests at word boundaries, normalization boundaries, etc.
173 */
174 testboth(0x1.87654ffffffffp+0, INFINITY, 0x1.87655p+0, 0, );
175 testboth(0x1.87655p+0, -INFINITY, 0x1.87654ffffffffp+0, 0, );
176 testboth(0x1.fffffffffffffp+0, INFINITY, 0x1p1, 0, );
177 testboth(0x1p1, -INFINITY, 0x1.fffffffffffffp+0, 0, );
178 testboth(0x0.fffffffffffffp-1022, INFINITY, 0x1p-1022, 0, );
179 testboth(0x1p-1022, -INFINITY, 0x0.fffffffffffffp-1022, ex_under, );
180
181 testboth(0x1.fffffep0f, INFINITY, 0x1p1, 0, f);
182 testboth(0x1p1, -INFINITY, 0x1.fffffep0f, 0, f);
183 testboth(0x0.fffffep-126f, INFINITY, 0x1p-126f, 0, f);
184 testboth(0x1p-126f, -INFINITY, 0x0.fffffep-126f, ex_under, f);
185
186 #if LDBL_MANT_DIG == 53
187 testboth(0x1.87654ffffffffp+0L, INFINITY, 0x1.87655p+0L, 0, l);
188 testboth(0x1.87655p+0L, -INFINITY, 0x1.87654ffffffffp+0L, 0, l);
189 testboth(0x1.fffffffffffffp+0L, INFINITY, 0x1p1L, 0, l);
190 testboth(0x1p1L, -INFINITY, 0x1.fffffffffffffp+0L, 0, l);
191 testboth(0x0.fffffffffffffp-1022L, INFINITY, 0x1p-1022L, 0, l);
192 testboth(0x1p-1022L, -INFINITY, 0x0.fffffffffffffp-1022L, ex_under, l);
193 #elif LDBL_MANT_DIG == 64 && !defined(__i386)
194 testboth(0x1.87654321fffffffep+0L, INFINITY, 0x1.87654322p+0L, 0, l);
195 testboth(0x1.87654322p+0L, -INFINITY, 0x1.87654321fffffffep+0L, 0, l);
196 testboth(0x1.fffffffffffffffep0L, INFINITY, 0x1p1L, 0, l);
197 testboth(0x1p1L, -INFINITY, 0x1.fffffffffffffffep0L, 0, l);
198 testboth(0x0.fffffffffffffffep-16382L, INFINITY, 0x1p-16382L, 0, l);
199 testboth(0x1p-16382L, -INFINITY,
200 0x0.fffffffffffffffep-16382L, ex_under, l);
201 #elif LDBL_MANT_DIG == 113
202 testboth(0x1.876543210987ffffffffffffffffp+0L, INFINITY,
203 0x1.876543210988p+0, 0, l);
204 testboth(0x1.876543210988p+0L, -INFINITY,
205 0x1.876543210987ffffffffffffffffp+0L, 0, l);
206 testboth(0x1.ffffffffffffffffffffffffffffp0L, INFINITY, 0x1p1L, 0, l);
207 testboth(0x1p1L, -INFINITY, 0x1.ffffffffffffffffffffffffffffp0L, 0, l);
208 testboth(0x0.ffffffffffffffffffffffffffffp-16382L, INFINITY,
209 0x1p-16382L, 0, l);
210 testboth(0x1p-16382L, -INFINITY,
211 0x0.ffffffffffffffffffffffffffffp-16382L, ex_under, l);
212 #endif
213 }
214
215 ATF_TC_WITHOUT_HEAD(overflow);
ATF_TC_BODY(overflow,tc)216 ATF_TC_BODY(overflow, tc)
217 {
218 long double ldbl_max;
219 /*
220 * We can't use a compile-time constant here because gcc on
221 * FreeBSD/i386 assumes long doubles are truncated to the
222 * double format.
223 */
224 ldbl_max = ldexpl(1.0 - ldbl_eps / 2, LDBL_MAX_EXP);
225
226 /*
227 * Overflow tests
228 */
229 test(idd(nextafter(DBL_MAX, INFINITY)), INFINITY, ex_over);
230 test(idd(nextafter(INFINITY, 0.0)), DBL_MAX, 0);
231 test(idd(nexttoward(DBL_MAX, DBL_MAX * 2.0L)), INFINITY, ex_over);
232 #if LDBL_MANT_DIG > 53
233 test(idd(nexttoward(INFINITY, DBL_MAX * 2.0L)), DBL_MAX, 0);
234 #endif
235
236 testf(idf(nextafterf(FLT_MAX, INFINITY)), INFINITY, ex_over);
237 testf(idf(nextafterf(INFINITY, 0.0)), FLT_MAX, 0);
238 testf(idf(nexttowardf(FLT_MAX, FLT_MAX * 2.0)), INFINITY, ex_over);
239 testf(idf(nexttowardf(INFINITY, FLT_MAX * 2.0)), FLT_MAX, 0);
240
241 testboth(ldbl_max, INFINITY, INFINITY, ex_over, l);
242 testboth(INFINITY, 0.0, ldbl_max, 0, l);
243 }
244
245 static void
_testl(const char * exp,int line,long double actual,long double expected,int except)246 _testl(const char *exp, int line, long double actual, long double expected,
247 int except)
248 {
249 int actual_except;
250
251 actual_except = fetestexcept(ALL_STD_EXCEPT);
252 if (!fpequal_cs(actual, expected, true)) {
253 atf_tc_fail_check(__FILE__, line,
254 "%s returned %La, expecting %La\n", exp, actual, expected);
255 }
256 if (actual_except != except) {
257 atf_tc_fail_check(__FILE__, line,
258 "%s raised 0x%x, expecting 0x%x\n", exp, actual_except,
259 except);
260 }
261 }
262
263 /*
264 * The idd() and idf() routines ensure that doubles and floats are
265 * converted to their respective types instead of stored in the FPU
266 * with extra precision.
267 */
268 static double
idd(double x)269 idd(double x)
270 {
271 return (x);
272 }
273
274 static float
idf(float x)275 idf(float x)
276 {
277 return (x);
278 }
279
ATF_TP_ADD_TCS(tp)280 ATF_TP_ADD_TCS(tp)
281 {
282 ATF_TP_ADD_TC(tp, zeros);
283 ATF_TP_ADD_TC(tp, ordinary);
284 ATF_TP_ADD_TC(tp, eq_and_nan);
285 ATF_TP_ADD_TC(tp, boundaries);
286 ATF_TP_ADD_TC(tp, overflow);
287
288 return (atf_no_error());
289 }
290