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 __FBSDID("$FreeBSD$"); 33 34 #include <assert.h> 35 #include <fenv.h> 36 #include <float.h> 37 #include <math.h> 38 #include <stdio.h> 39 40 #ifdef __i386__ 41 #include <ieeefp.h> 42 #endif 43 44 #include "test-utils.h" 45 46 #pragma STDC FENV_ACCESS ON 47 48 /* 49 * Test that a function returns the correct value and sets the 50 * exception flags correctly. The exceptmask specifies which 51 * exceptions we should check. We need to be lenient for several 52 * reasoons, but mainly because on some architectures it's impossible 53 * to raise FE_OVERFLOW without raising FE_INEXACT. 54 * 55 * These are macros instead of functions so that assert provides more 56 * meaningful error messages. 57 * 58 * XXX The volatile here is to avoid gcc's bogus constant folding and work 59 * around the lack of support for the FENV_ACCESS pragma. 60 */ 61 #define test(func, x, result, exceptmask, excepts) do { \ 62 volatile long double _d = x; \ 63 assert(feclearexcept(FE_ALL_EXCEPT) == 0); \ 64 assert(fpequal((func)(_d), (result))); \ 65 assert(((void)(func), fetestexcept(exceptmask) == (excepts))); \ 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 static void 126 run_exp2_tests(void) 127 { 128 unsigned i; 129 130 /* 131 * We should insist that exp2() return exactly the correct 132 * result and not raise an inexact exception for integer 133 * arguments. 134 */ 135 feclearexcept(FE_ALL_EXCEPT); 136 for (i = FLT_MIN_EXP - FLT_MANT_DIG; i < FLT_MAX_EXP; i++) { 137 assert(exp2f(i) == ldexpf(1.0, i)); 138 assert(fetestexcept(ALL_STD_EXCEPT) == 0); 139 } 140 for (i = DBL_MIN_EXP - DBL_MANT_DIG; i < DBL_MAX_EXP; i++) { 141 assert(exp2(i) == ldexp(1.0, i)); 142 assert(fetestexcept(ALL_STD_EXCEPT) == 0); 143 } 144 for (i = LDBL_MIN_EXP - LDBL_MANT_DIG; i < LDBL_MAX_EXP; i++) { 145 assert(exp2l(i) == ldexpl(1.0, i)); 146 assert(fetestexcept(ALL_STD_EXCEPT) == 0); 147 } 148 } 149 150 int 151 main(void) 152 { 153 154 printf("1..3\n"); 155 156 run_generic_tests(); 157 printf("ok 1 - exponential\n"); 158 159 #ifdef __i386__ 160 fpsetprec(FP_PE); 161 run_generic_tests(); 162 #endif 163 printf("ok 2 - exponential\n"); 164 165 run_exp2_tests(); 166 printf("ok 3 - exponential\n"); 167 168 return (0); 169 } 170