1 /* $OpenBSD: exponential_test.c,v 1.3 2021/12/13 18:04:28 deraadt Exp $ */ 2 /*- 3 * Copyright (c) 2008 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 * Tests for corner cases in exp*(). 32 */ 33 34 #include <fenv.h> 35 #include <float.h> 36 #include <math.h> 37 #include <stdio.h> 38 39 #ifdef __i386__ 40 #include <ieeefp.h> 41 #endif 42 43 #include "test-utils.h" 44 45 #pragma STDC FENV_ACCESS ON 46 47 /* 48 * Test that a function returns the correct value and sets the 49 * exception flags correctly. The exceptmask specifies which 50 * exceptions we should check. We need to be lenient for several 51 * reasoons, but mainly because on some architectures it's impossible 52 * to raise FE_OVERFLOW without raising FE_INEXACT. 53 * 54 * These are macros instead of functions so that assert provides more 55 * meaningful error messages. 56 * 57 * XXX The volatile here is to avoid gcc's bogus constant folding and work 58 * around the lack of support for the FENV_ACCESS pragma. 59 */ 60 #define test(func, x, result, exceptmask, excepts) do { \ 61 volatile long double _d = x; \ 62 ATF_REQUIRE_EQ(0, feclearexcept(FE_ALL_EXCEPT)); \ 63 CHECK_FPEQUAL((func)(_d), (result)); \ 64 CHECK_FP_EXCEPTIONS_MSG(excepts, exceptmask, "for %s(%s)", \ 65 #func, #x); \ 66 } while (0) 67 68 /* Test all the functions that compute b^x. */ 69 #define _testall0(x, result, exceptmask, excepts) do { \ 70 test(exp, x, result, exceptmask, excepts); \ 71 test(expf, x, result, exceptmask, excepts); \ 72 test(exp2, x, result, exceptmask, excepts); \ 73 test(exp2f, x, result, exceptmask, excepts); \ 74 } while (0) 75 76 /* Skip over exp2l on platforms that don't support it. */ 77 #if LDBL_PREC == 53 78 #define testall0 _testall0 79 #else 80 #define testall0(x, result, exceptmask, excepts) do { \ 81 _testall0(x, result, exceptmask, excepts); \ 82 test(exp2l, x, result, exceptmask, excepts); \ 83 } while (0) 84 #endif 85 86 /* Test all the functions that compute b^x - 1. */ 87 #define testall1(x, result, exceptmask, excepts) do { \ 88 test(expm1, x, result, exceptmask, excepts); \ 89 test(expm1f, x, result, exceptmask, excepts); \ 90 } while (0) 91 92 static void 93 run_generic_tests(void) 94 { 95 96 /* exp(0) == 1, no exceptions raised */ 97 testall0(0.0, 1.0, ALL_STD_EXCEPT, 0); 98 testall1(0.0, 0.0, ALL_STD_EXCEPT, 0); 99 testall0(-0.0, 1.0, ALL_STD_EXCEPT, 0); 100 testall1(-0.0, -0.0, ALL_STD_EXCEPT, 0); 101 102 /* exp(NaN) == NaN, no exceptions raised */ 103 testall0(NAN, NAN, ALL_STD_EXCEPT, 0); 104 testall1(NAN, NAN, ALL_STD_EXCEPT, 0); 105 106 /* exp(Inf) == Inf, no exceptions raised */ 107 testall0(INFINITY, INFINITY, ALL_STD_EXCEPT, 0); 108 testall1(INFINITY, INFINITY, ALL_STD_EXCEPT, 0); 109 110 /* exp(-Inf) == 0, no exceptions raised */ 111 testall0(-INFINITY, 0.0, ALL_STD_EXCEPT, 0); 112 testall1(-INFINITY, -1.0, ALL_STD_EXCEPT, 0); 113 114 #if !defined(__i386__) 115 /* exp(big) == Inf, overflow exception */ 116 testall0(50000.0, INFINITY, ALL_STD_EXCEPT & ~FE_INEXACT, FE_OVERFLOW); 117 testall1(50000.0, INFINITY, ALL_STD_EXCEPT & ~FE_INEXACT, FE_OVERFLOW); 118 119 /* exp(small) == 0, underflow and inexact exceptions */ 120 testall0(-50000.0, 0.0, ALL_STD_EXCEPT, FE_UNDERFLOW | FE_INEXACT); 121 #endif 122 testall1(-50000.0, -1.0, ALL_STD_EXCEPT, FE_INEXACT); 123 } 124 125 126 /* 127 * We should insist that exp2() return exactly the correct 128 * result and not raise an inexact exception for integer 129 * arguments. 130 */ 131 ATF_TC_WITHOUT_HEAD(exp2f); 132 ATF_TC_BODY(exp2f, tc) 133 { 134 int i; 135 ATF_REQUIRE_EQ(0, feclearexcept(FE_ALL_EXCEPT)); 136 for (i = FLT_MIN_EXP - FLT_MANT_DIG; i < FLT_MAX_EXP; i++) { 137 ATF_CHECK_EQ(exp2f(i), ldexpf(1.0, i)); 138 CHECK_FP_EXCEPTIONS(0, ALL_STD_EXCEPT); 139 } 140 } 141 142 ATF_TC_WITHOUT_HEAD(exp2); 143 ATF_TC_BODY(exp2, tc) 144 { 145 int i; 146 ATF_REQUIRE_EQ(0, feclearexcept(FE_ALL_EXCEPT)); 147 for (i = DBL_MIN_EXP - DBL_MANT_DIG; i < DBL_MAX_EXP; i++) { 148 ATF_CHECK_EQ(exp2(i), ldexp(1.0, i)); 149 CHECK_FP_EXCEPTIONS(0, ALL_STD_EXCEPT); 150 } 151 } 152 153 ATF_TC_WITHOUT_HEAD(exp2l); 154 ATF_TC_BODY(exp2l, tc) 155 { 156 int i; 157 ATF_REQUIRE_EQ(0, feclearexcept(FE_ALL_EXCEPT)); 158 for (i = LDBL_MIN_EXP - LDBL_MANT_DIG; i < LDBL_MAX_EXP; i++) { 159 ATF_CHECK_EQ(exp2l(i), ldexpl(1.0, i)); 160 CHECK_FP_EXCEPTIONS(0, ALL_STD_EXCEPT); 161 } 162 } 163 164 ATF_TC_WITHOUT_HEAD(generic); 165 ATF_TC_BODY(generic, tc) 166 { 167 run_generic_tests(); 168 } 169 170 #ifndef __OpenBSD__ 171 #ifdef __i386__ 172 ATF_TC_WITHOUT_HEAD(generic_fp_pe); 173 ATF_TC_BODY(generic_fp_pe, tc) 174 { 175 fpsetprec(FP_PE); 176 run_generic_tests(); 177 } 178 #endif 179 #endif 180 181 ATF_TP_ADD_TCS(tp) 182 { 183 ATF_TP_ADD_TC(tp, generic); 184 #ifndef __OpenBSD__ 185 #ifdef __i386__ 186 ATF_TP_ADD_TC(tp, generic_fp_pe); 187 #endif 188 #endif 189 ATF_TP_ADD_TC(tp, exp2); 190 ATF_TP_ADD_TC(tp, exp2f); 191 ATF_TP_ADD_TC(tp, exp2l); 192 193 return (atf_no_error()); 194 } 195