1 /* Decimal context header module for the decNumber C Library. 2 Copyright (C) 2005, 2007 Free Software Foundation, Inc. 3 Contributed by IBM Corporation. Author Mike Cowlishaw. 4 5 This file is part of GCC. 6 7 GCC is free software; you can redistribute it and/or modify it under 8 the terms of the GNU General Public License as published by the Free 9 Software Foundation; either version 2, or (at your option) any later 10 version. 11 12 In addition to the permissions in the GNU General Public License, 13 the Free Software Foundation gives you unlimited permission to link 14 the compiled version of this file into combinations with other 15 programs, and to distribute those combinations without any 16 restriction coming from the use of this file. (The General Public 17 License restrictions do apply in other respects; for example, they 18 cover modification of the file, and distribution when not linked 19 into a combine executable.) 20 21 GCC is distributed in the hope that it will be useful, but WITHOUT ANY 22 WARRANTY; without even the implied warranty of MERCHANTABILITY or 23 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 24 for more details. 25 26 You should have received a copy of the GNU General Public License 27 along with GCC; see the file COPYING. If not, write to the Free 28 Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 29 02110-1301, USA. */ 30 31 /* ------------------------------------------------------------------ */ 32 /* Decimal Context module header */ 33 /* ------------------------------------------------------------------ */ 34 /* */ 35 /* Context variables must always have valid values: */ 36 /* */ 37 /* status -- [any bits may be cleared, but not set, by user] */ 38 /* round -- must be one of the enumerated rounding modes */ 39 /* */ 40 /* The following variables are implied for fixed size formats (i.e., */ 41 /* they are ignored) but should still be set correctly in case used */ 42 /* with decNumber functions: */ 43 /* */ 44 /* clamp -- must be either 0 or 1 */ 45 /* digits -- must be in the range 1 through 999999999 */ 46 /* emax -- must be in the range 0 through 999999999 */ 47 /* emin -- must be in the range 0 through -999999999 */ 48 /* extended -- must be either 0 or 1 [present only if DECSUBSET] */ 49 /* traps -- only defined bits may be set */ 50 /* */ 51 /* ------------------------------------------------------------------ */ 52 53 #ifndef DECCONTEXT_H 54 #define DECCONTEXT_H 55 56 #define DECCNAME "decContext" /* Short name */ 57 #define DECCFULLNAME "Decimal Context Descriptor" /* Verbose name */ 58 #define DECCAUTHOR "Mike Cowlishaw" /* Who to blame */ 59 60 61 /* Extended flags setting -- set this to 0 to use only IEEE flags */ 62 #define DECEXTFLAG 1 /* 1=enable extended flags */ 63 64 /* Conditional code flag -- set this to 0 for best performance */ 65 #define DECSUBSET 0 /* 1=enable subset arithmetic */ 66 67 /* Context for operations, with associated constants */ 68 enum rounding { 69 DEC_ROUND_CEILING, /* round towards +infinity */ 70 DEC_ROUND_UP, /* round away from 0 */ 71 DEC_ROUND_HALF_UP, /* 0.5 rounds up */ 72 DEC_ROUND_HALF_EVEN, /* 0.5 rounds to nearest even */ 73 DEC_ROUND_HALF_DOWN, /* 0.5 rounds down */ 74 DEC_ROUND_DOWN, /* round towards 0 (truncate) */ 75 DEC_ROUND_FLOOR, /* round towards -infinity */ 76 DEC_ROUND_05UP, /* round for reround */ 77 DEC_ROUND_MAX /* enum must be less than this */ 78 }; 79 #define DEC_ROUND_DEFAULT DEC_ROUND_HALF_EVEN; 80 81 typedef struct { 82 int32_t digits; /* working precision */ 83 int32_t emax; /* maximum positive exponent */ 84 int32_t emin; /* minimum negative exponent */ 85 enum rounding round; /* rounding mode */ 86 uint32_t traps; /* trap-enabler flags */ 87 uint32_t status; /* status flags */ 88 uint8_t clamp; /* flag: apply IEEE exponent clamp */ 89 #if DECSUBSET 90 uint8_t extended; /* flag: special-values allowed */ 91 #endif 92 } decContext; 93 94 /* Maxima and Minima for context settings */ 95 #define DEC_MAX_DIGITS 999999999 96 #define DEC_MIN_DIGITS 1 97 #define DEC_MAX_EMAX 999999999 98 #define DEC_MIN_EMAX 0 99 #define DEC_MAX_EMIN 0 100 #define DEC_MIN_EMIN -999999999 101 #define DEC_MAX_MATH 999999 /* max emax, etc., for math funcs. */ 102 103 /* Classifications for decimal numbers, aligned with 754r (note */ 104 /* that 'normal' and 'subnormal' are meaningful only with a */ 105 /* decContext or a fixed size format). */ 106 enum decClass { 107 DEC_CLASS_SNAN, 108 DEC_CLASS_QNAN, 109 DEC_CLASS_NEG_INF, 110 DEC_CLASS_NEG_NORMAL, 111 DEC_CLASS_NEG_SUBNORMAL, 112 DEC_CLASS_NEG_ZERO, 113 DEC_CLASS_POS_ZERO, 114 DEC_CLASS_POS_SUBNORMAL, 115 DEC_CLASS_POS_NORMAL, 116 DEC_CLASS_POS_INF 117 }; 118 /* Strings for the decClasses */ 119 #define DEC_ClassString_SN "sNaN" 120 #define DEC_ClassString_QN "NaN" 121 #define DEC_ClassString_NI "-Infinity" 122 #define DEC_ClassString_NN "-Normal" 123 #define DEC_ClassString_NS "-Subnormal" 124 #define DEC_ClassString_NZ "-Zero" 125 #define DEC_ClassString_PZ "+Zero" 126 #define DEC_ClassString_PS "+Subnormal" 127 #define DEC_ClassString_PN "+Normal" 128 #define DEC_ClassString_PI "+Infinity" 129 #define DEC_ClassString_UN "Invalid" 130 131 /* Trap-enabler and Status flags (exceptional conditions), and */ 132 /* their names. The top byte is reserved for internal use */ 133 #if DECEXTFLAG 134 /* Extended flags */ 135 #define DEC_Conversion_syntax 0x00000001 136 #define DEC_Division_by_zero 0x00000002 137 #define DEC_Division_impossible 0x00000004 138 #define DEC_Division_undefined 0x00000008 139 #define DEC_Insufficient_storage 0x00000010 /* [when malloc fails] */ 140 #define DEC_Inexact 0x00000020 141 #define DEC_Invalid_context 0x00000040 142 #define DEC_Invalid_operation 0x00000080 143 #if DECSUBSET 144 #define DEC_Lost_digits 0x00000100 145 #endif 146 #define DEC_Overflow 0x00000200 147 #define DEC_Clamped 0x00000400 148 #define DEC_Rounded 0x00000800 149 #define DEC_Subnormal 0x00001000 150 #define DEC_Underflow 0x00002000 151 #else 152 /* IEEE flags only */ 153 #define DEC_Conversion_syntax 0x00000010 154 #define DEC_Division_by_zero 0x00000002 155 #define DEC_Division_impossible 0x00000010 156 #define DEC_Division_undefined 0x00000010 157 #define DEC_Insufficient_storage 0x00000010 /* [when malloc fails] */ 158 #define DEC_Inexact 0x00000001 159 #define DEC_Invalid_context 0x00000010 160 #define DEC_Invalid_operation 0x00000010 161 #if DECSUBSET 162 #define DEC_Lost_digits 0x00000000 163 #endif 164 #define DEC_Overflow 0x00000008 165 #define DEC_Clamped 0x00000000 166 #define DEC_Rounded 0x00000000 167 #define DEC_Subnormal 0x00000000 168 #define DEC_Underflow 0x00000004 169 #endif 170 171 /* IEEE 854 groupings for the flags */ 172 /* [DEC_Clamped, DEC_Lost_digits, DEC_Rounded, and DEC_Subnormal */ 173 /* are not in IEEE 854] */ 174 #define DEC_IEEE_854_Division_by_zero (DEC_Division_by_zero) 175 #if DECSUBSET 176 #define DEC_IEEE_854_Inexact (DEC_Inexact | DEC_Lost_digits) 177 #else 178 #define DEC_IEEE_854_Inexact (DEC_Inexact) 179 #endif 180 #define DEC_IEEE_854_Invalid_operation (DEC_Conversion_syntax | \ 181 DEC_Division_impossible | \ 182 DEC_Division_undefined | \ 183 DEC_Insufficient_storage | \ 184 DEC_Invalid_context | \ 185 DEC_Invalid_operation) 186 #define DEC_IEEE_854_Overflow (DEC_Overflow) 187 #define DEC_IEEE_854_Underflow (DEC_Underflow) 188 189 /* flags which are normally errors (result is qNaN, infinite, or 0) */ 190 #define DEC_Errors (DEC_IEEE_854_Division_by_zero | \ 191 DEC_IEEE_854_Invalid_operation | \ 192 DEC_IEEE_854_Overflow | DEC_IEEE_854_Underflow) 193 /* flags which cause a result to become qNaN */ 194 #define DEC_NaNs DEC_IEEE_854_Invalid_operation 195 196 /* flags which are normally for information only (finite results) */ 197 #if DECSUBSET 198 #define DEC_Information (DEC_Clamped | DEC_Rounded | DEC_Inexact \ 199 | DEC_Lost_digits) 200 #else 201 #define DEC_Information (DEC_Clamped | DEC_Rounded | DEC_Inexact) 202 #endif 203 204 /* Name strings for the exceptional conditions */ 205 #define DEC_Condition_CS "Conversion syntax" 206 #define DEC_Condition_DZ "Division by zero" 207 #define DEC_Condition_DI "Division impossible" 208 #define DEC_Condition_DU "Division undefined" 209 #define DEC_Condition_IE "Inexact" 210 #define DEC_Condition_IS "Insufficient storage" 211 #define DEC_Condition_IC "Invalid context" 212 #define DEC_Condition_IO "Invalid operation" 213 #if DECSUBSET 214 #define DEC_Condition_LD "Lost digits" 215 #endif 216 #define DEC_Condition_OV "Overflow" 217 #define DEC_Condition_PA "Clamped" 218 #define DEC_Condition_RO "Rounded" 219 #define DEC_Condition_SU "Subnormal" 220 #define DEC_Condition_UN "Underflow" 221 #define DEC_Condition_ZE "No status" 222 #define DEC_Condition_MU "Multiple status" 223 #define DEC_Condition_Length 21 /* length of the longest string, */ 224 /* including terminator */ 225 226 /* Initialization descriptors, used by decContextDefault */ 227 #define DEC_INIT_BASE 0 228 #define DEC_INIT_DECIMAL32 32 229 #define DEC_INIT_DECIMAL64 64 230 #define DEC_INIT_DECIMAL128 128 231 /* Synonyms */ 232 #define DEC_INIT_DECSINGLE DEC_INIT_DECIMAL32 233 #define DEC_INIT_DECDOUBLE DEC_INIT_DECIMAL64 234 #define DEC_INIT_DECQUAD DEC_INIT_DECIMAL128 235 236 /* decContext routines */ 237 238 239 extern decContext * decContextClearStatus(decContext *, uint32_t); 240 extern decContext * decContextDefault(decContext *, int32_t); 241 extern enum rounding decContextGetRounding(decContext *); 242 extern uint32_t decContextGetStatus(decContext *); 243 extern decContext * decContextRestoreStatus(decContext *, uint32_t, uint32_t); 244 extern uint32_t decContextSaveStatus(decContext *, uint32_t); 245 extern decContext * decContextSetRounding(decContext *, enum rounding); 246 extern decContext * decContextSetStatus(decContext *, uint32_t); 247 extern decContext * decContextSetStatusFromString(decContext *, const char *); 248 extern decContext * decContextSetStatusFromStringQuiet(decContext *, const char *); 249 extern decContext * decContextSetStatusQuiet(decContext *, uint32_t); 250 extern const char * decContextStatusToString(const decContext *); 251 extern uint32_t decContextTestSavedStatus(uint32_t, uint32_t); 252 extern uint32_t decContextTestStatus(decContext *, uint32_t); 253 extern decContext * decContextZeroStatus(decContext *); 254 255 #endif 256