1 /*-
2 * Copyright (c) 2008 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 exp*().
29 */
30
31 #include <sys/cdefs.h>
32 #include <fenv.h>
33 #include <float.h>
34 #include <math.h>
35 #include <stdio.h>
36
37 #ifdef __i386__
38 #include <ieeefp.h>
39 #endif
40
41 #include "test-utils.h"
42
43 #pragma STDC FENV_ACCESS ON
44
45 /*
46 * Test that a function returns the correct value and sets the
47 * exception flags correctly. The exceptmask specifies which
48 * exceptions we should check. We need to be lenient for several
49 * reasoons, but mainly because on some architectures it's impossible
50 * to raise FE_OVERFLOW without raising FE_INEXACT.
51 *
52 * These are macros instead of functions so that assert provides more
53 * meaningful error messages.
54 *
55 * XXX The volatile here is to avoid gcc's bogus constant folding and work
56 * around the lack of support for the FENV_ACCESS pragma.
57 */
58 #define test(func, x, result, exceptmask, excepts) do { \
59 volatile long double _d = x; \
60 ATF_REQUIRE_EQ(0, feclearexcept(FE_ALL_EXCEPT)); \
61 CHECK_FPEQUAL((func)(_d), (result)); \
62 CHECK_FP_EXCEPTIONS_MSG(excepts, exceptmask, "for %s(%s)", \
63 #func, #x); \
64 } while (0)
65
66 /* Test all the functions that compute b^x. */
67 #define _testall0(x, result, exceptmask, excepts) do { \
68 test(exp, x, result, exceptmask, excepts); \
69 test(expf, x, result, exceptmask, excepts); \
70 test(exp2, x, result, exceptmask, excepts); \
71 test(exp2f, x, result, exceptmask, excepts); \
72 } while (0)
73
74 /* Skip over exp2l on platforms that don't support it. */
75 #if LDBL_PREC == 53
76 #define testall0 _testall0
77 #else
78 #define testall0(x, result, exceptmask, excepts) do { \
79 _testall0(x, result, exceptmask, excepts); \
80 test(exp2l, x, result, exceptmask, excepts); \
81 } while (0)
82 #endif
83
84 /* Test all the functions that compute b^x - 1. */
85 #define testall1(x, result, exceptmask, excepts) do { \
86 test(expm1, x, result, exceptmask, excepts); \
87 test(expm1f, x, result, exceptmask, excepts); \
88 } while (0)
89
90 static void
run_generic_tests(void)91 run_generic_tests(void)
92 {
93
94 /* exp(0) == 1, no exceptions raised */
95 testall0(0.0, 1.0, ALL_STD_EXCEPT, 0);
96 testall1(0.0, 0.0, ALL_STD_EXCEPT, 0);
97 testall0(-0.0, 1.0, ALL_STD_EXCEPT, 0);
98 testall1(-0.0, -0.0, ALL_STD_EXCEPT, 0);
99
100 /* exp(NaN) == NaN, no exceptions raised */
101 testall0(NAN, NAN, ALL_STD_EXCEPT, 0);
102 testall1(NAN, NAN, ALL_STD_EXCEPT, 0);
103
104 /* exp(Inf) == Inf, no exceptions raised */
105 testall0(INFINITY, INFINITY, ALL_STD_EXCEPT, 0);
106 testall1(INFINITY, INFINITY, ALL_STD_EXCEPT, 0);
107
108 /* exp(-Inf) == 0, no exceptions raised */
109 testall0(-INFINITY, 0.0, ALL_STD_EXCEPT, 0);
110 testall1(-INFINITY, -1.0, ALL_STD_EXCEPT, 0);
111
112 #if !defined(__i386__)
113 /* exp(big) == Inf, overflow exception */
114 testall0(50000.0, INFINITY, ALL_STD_EXCEPT & ~FE_INEXACT, FE_OVERFLOW);
115 testall1(50000.0, INFINITY, ALL_STD_EXCEPT & ~FE_INEXACT, FE_OVERFLOW);
116
117 /* exp(small) == 0, underflow and inexact exceptions */
118 testall0(-50000.0, 0.0, ALL_STD_EXCEPT, FE_UNDERFLOW | FE_INEXACT);
119 #endif
120 testall1(-50000.0, -1.0, ALL_STD_EXCEPT, FE_INEXACT);
121 }
122
123
124 /*
125 * We should insist that exp2() return exactly the correct
126 * result and not raise an inexact exception for integer
127 * arguments.
128 */
129 ATF_TC_WITHOUT_HEAD(exp2f);
ATF_TC_BODY(exp2f,tc)130 ATF_TC_BODY(exp2f, tc)
131 {
132 ATF_REQUIRE_EQ(0, feclearexcept(FE_ALL_EXCEPT));
133 for (int i = FLT_MIN_EXP - FLT_MANT_DIG; i < FLT_MAX_EXP; i++) {
134 ATF_CHECK_EQ(exp2f(i), ldexpf(1.0, i));
135 CHECK_FP_EXCEPTIONS(0, ALL_STD_EXCEPT);
136 }
137 }
138
139 ATF_TC_WITHOUT_HEAD(exp2);
ATF_TC_BODY(exp2,tc)140 ATF_TC_BODY(exp2, tc)
141 {
142 ATF_REQUIRE_EQ(0, feclearexcept(FE_ALL_EXCEPT));
143 for (int i = DBL_MIN_EXP - DBL_MANT_DIG; i < DBL_MAX_EXP; i++) {
144 ATF_CHECK_EQ(exp2(i), ldexp(1.0, i));
145 CHECK_FP_EXCEPTIONS(0, ALL_STD_EXCEPT);
146 }
147 }
148
149 ATF_TC_WITHOUT_HEAD(exp2l);
ATF_TC_BODY(exp2l,tc)150 ATF_TC_BODY(exp2l, tc)
151 {
152 ATF_REQUIRE_EQ(0, feclearexcept(FE_ALL_EXCEPT));
153 for (int i = LDBL_MIN_EXP - LDBL_MANT_DIG; i < LDBL_MAX_EXP; i++) {
154 ATF_CHECK_EQ(exp2l(i), ldexpl(1.0, i));
155 CHECK_FP_EXCEPTIONS(0, ALL_STD_EXCEPT);
156 }
157 }
158
159 ATF_TC_WITHOUT_HEAD(generic);
ATF_TC_BODY(generic,tc)160 ATF_TC_BODY(generic, tc)
161 {
162 run_generic_tests();
163 }
164
165 #ifdef __i386__
166 ATF_TC_WITHOUT_HEAD(generic_fp_pe);
ATF_TC_BODY(generic_fp_pe,tc)167 ATF_TC_BODY(generic_fp_pe, tc)
168 {
169 fpsetprec(FP_PE);
170 run_generic_tests();
171 }
172 #endif
173
ATF_TP_ADD_TCS(tp)174 ATF_TP_ADD_TCS(tp)
175 {
176 ATF_TP_ADD_TC(tp, generic);
177 #ifdef __i386__
178 ATF_TP_ADD_TC(tp, generic_fp_pe);
179 #endif
180 ATF_TP_ADD_TC(tp, exp2);
181 ATF_TP_ADD_TC(tp, exp2f);
182 ATF_TP_ADD_TC(tp, exp2l);
183
184 return (atf_no_error());
185 }
186