1 /* Test of signbit() substitute. 2 Copyright (C) 2007-2018 Free Software Foundation, Inc. 3 4 This program is free software: you can redistribute it and/or modify 5 it under the terms of the GNU General Public License as published by 6 the Free Software Foundation; either version 3 of the License, or 7 (at your option) any later version. 8 9 This program is distributed in the hope that it will be useful, 10 but WITHOUT ANY WARRANTY; without even the implied warranty of 11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 GNU General Public License for more details. 13 14 You should have received a copy of the GNU General Public License 15 along with this program. If not, see <https://www.gnu.org/licenses/>. */ 16 17 /* Written by Bruno Haible <bruno@clisp.org>, 2007. */ 18 19 #include <config.h> 20 21 #include <math.h> 22 23 /* signbit must be a macro. */ 24 #ifndef signbit 25 # error missing declaration 26 #endif 27 28 #include <float.h> 29 #include <limits.h> 30 31 #include "minus-zero.h" 32 #include "infinity.h" 33 #include "macros.h" 34 35 float zerof = 0.0f; 36 double zerod = 0.0; 37 long double zerol = 0.0L; 38 39 static void test_signbitf()40test_signbitf () 41 { 42 /* Finite values. */ 43 ASSERT (!signbit (3.141f)); 44 ASSERT (!signbit (3.141e30f)); 45 ASSERT (!signbit (3.141e-30f)); 46 ASSERT (signbit (-2.718f)); 47 ASSERT (signbit (-2.718e30f)); 48 ASSERT (signbit (-2.718e-30f)); 49 /* Zeros. */ 50 ASSERT (!signbit (0.0f)); 51 if (1.0f / minus_zerof < 0) 52 ASSERT (signbit (minus_zerof)); 53 else 54 ASSERT (!signbit (minus_zerof)); 55 /* Infinite values. */ 56 ASSERT (!signbit (Infinityf ())); 57 ASSERT (signbit (- Infinityf ())); 58 /* Quiet NaN. */ 59 (void) signbit (zerof / zerof); 60 #if defined FLT_EXPBIT0_WORD && defined FLT_EXPBIT0_BIT 61 /* Signalling NaN. */ 62 { 63 #define NWORDS \ 64 ((sizeof (float) + sizeof (unsigned int) - 1) / sizeof (unsigned int)) 65 typedef union { float value; unsigned int word[NWORDS]; } memory_float; 66 memory_float m; 67 m.value = zerof / zerof; 68 # if FLT_EXPBIT0_BIT > 0 69 m.word[FLT_EXPBIT0_WORD] ^= (unsigned int) 1 << (FLT_EXPBIT0_BIT - 1); 70 # else 71 m.word[FLT_EXPBIT0_WORD + (FLT_EXPBIT0_WORD < NWORDS / 2 ? 1 : - 1)] 72 ^= (unsigned int) 1 << (sizeof (unsigned int) * CHAR_BIT - 1); 73 # endif 74 if (FLT_EXPBIT0_WORD < NWORDS / 2) 75 m.word[FLT_EXPBIT0_WORD + 1] |= (unsigned int) 1 << FLT_EXPBIT0_BIT; 76 else 77 m.word[0] |= (unsigned int) 1; 78 (void) signbit (m.value); 79 #undef NWORDS 80 } 81 #endif 82 } 83 84 static void test_signbitd()85test_signbitd () 86 { 87 /* Finite values. */ 88 ASSERT (!signbit (3.141)); 89 ASSERT (!signbit (3.141e30)); 90 ASSERT (!signbit (3.141e-30)); 91 ASSERT (signbit (-2.718)); 92 ASSERT (signbit (-2.718e30)); 93 ASSERT (signbit (-2.718e-30)); 94 /* Zeros. */ 95 ASSERT (!signbit (0.0)); 96 if (1.0 / minus_zerod < 0) 97 ASSERT (signbit (minus_zerod)); 98 else 99 ASSERT (!signbit (minus_zerod)); 100 /* Infinite values. */ 101 ASSERT (!signbit (Infinityd ())); 102 ASSERT (signbit (- Infinityd ())); 103 /* Quiet NaN. */ 104 (void) signbit (zerod / zerod); 105 #if defined DBL_EXPBIT0_WORD && defined DBL_EXPBIT0_BIT 106 /* Signalling NaN. */ 107 { 108 #define NWORDS \ 109 ((sizeof (double) + sizeof (unsigned int) - 1) / sizeof (unsigned int)) 110 typedef union { double value; unsigned int word[NWORDS]; } memory_double; 111 memory_double m; 112 m.value = zerod / zerod; 113 # if DBL_EXPBIT0_BIT > 0 114 m.word[DBL_EXPBIT0_WORD] ^= (unsigned int) 1 << (DBL_EXPBIT0_BIT - 1); 115 # else 116 m.word[DBL_EXPBIT0_WORD + (DBL_EXPBIT0_WORD < NWORDS / 2 ? 1 : - 1)] 117 ^= (unsigned int) 1 << (sizeof (unsigned int) * CHAR_BIT - 1); 118 # endif 119 m.word[DBL_EXPBIT0_WORD + (DBL_EXPBIT0_WORD < NWORDS / 2 ? 1 : - 1)] 120 |= (unsigned int) 1 << DBL_EXPBIT0_BIT; 121 (void) signbit (m.value); 122 #undef NWORDS 123 } 124 #endif 125 } 126 127 static void test_signbitl()128test_signbitl () 129 { 130 /* Finite values. */ 131 ASSERT (!signbit (3.141L)); 132 ASSERT (!signbit (3.141e30L)); 133 ASSERT (!signbit (3.141e-30L)); 134 ASSERT (signbit (-2.718L)); 135 ASSERT (signbit (-2.718e30L)); 136 ASSERT (signbit (-2.718e-30L)); 137 /* Zeros. */ 138 ASSERT (!signbit (0.0L)); 139 if (1.0L / minus_zerol < 0) 140 ASSERT (signbit (minus_zerol)); 141 else 142 ASSERT (!signbit (minus_zerol)); 143 /* Infinite values. */ 144 ASSERT (!signbit (Infinityl ())); 145 ASSERT (signbit (- Infinityl ())); 146 /* Quiet NaN. */ 147 (void) signbit (zerol / zerol); 148 #if defined LDBL_EXPBIT0_WORD && defined LDBL_EXPBIT0_BIT 149 /* Signalling NaN. */ 150 { 151 #define NWORDS \ 152 ((sizeof (long double) + sizeof (unsigned int) - 1) / sizeof (unsigned int)) 153 typedef union { long double value; unsigned int word[NWORDS]; } memory_long_double; 154 155 #if defined __powerpc__ && LDBL_MANT_DIG == 106 156 /* This is PowerPC "double double", a pair of two doubles. Inf and Nan are 157 represented as the corresponding 64-bit IEEE values in the first double; 158 the second is ignored. Manipulate only the first double. */ 159 #undef NWORDS 160 #define NWORDS \ 161 ((sizeof (double) + sizeof (unsigned int) - 1) / sizeof (unsigned int)) 162 #endif 163 164 memory_long_double m; 165 m.value = zerol / zerol; 166 # if LDBL_EXPBIT0_BIT > 0 167 m.word[LDBL_EXPBIT0_WORD] ^= (unsigned int) 1 << (LDBL_EXPBIT0_BIT - 1); 168 # else 169 m.word[LDBL_EXPBIT0_WORD + (LDBL_EXPBIT0_WORD < NWORDS / 2 ? 1 : - 1)] 170 ^= (unsigned int) 1 << (sizeof (unsigned int) * CHAR_BIT - 1); 171 # endif 172 m.word[LDBL_EXPBIT0_WORD + (LDBL_EXPBIT0_WORD < NWORDS / 2 ? 1 : - 1)] 173 |= (unsigned int) 1 << LDBL_EXPBIT0_BIT; 174 (void) signbit (m.value); 175 #undef NWORDS 176 } 177 #endif 178 } 179 180 int main()181main () 182 { 183 test_signbitf (); 184 test_signbitd (); 185 test_signbitl (); 186 return 0; 187 } 188