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 #if !defined(DECCONTEXT) 54 #define DECCONTEXT 55 #define DECCNAME "decContext" /* Short name */ 56 #define DECCFULLNAME "Decimal Context Descriptor" /* Verbose name */ 57 #define DECCAUTHOR "Mike Cowlishaw" /* Who to blame */ 58 59 60 /* Extended flags setting -- set this to 0 to use only IEEE flags */ 61 #define DECEXTFLAG 1 /* 1=enable extended flags */ 62 63 /* Conditional code flag -- set this to 0 for best performance */ 64 #define DECSUBSET 0 /* 1=enable subset arithmetic */ 65 66 /* Context for operations, with associated constants */ 67 enum rounding { 68 DEC_ROUND_CEILING, /* round towards +infinity */ 69 DEC_ROUND_UP, /* round away from 0 */ 70 DEC_ROUND_HALF_UP, /* 0.5 rounds up */ 71 DEC_ROUND_HALF_EVEN, /* 0.5 rounds to nearest even */ 72 DEC_ROUND_HALF_DOWN, /* 0.5 rounds down */ 73 DEC_ROUND_DOWN, /* round towards 0 (truncate) */ 74 DEC_ROUND_FLOOR, /* round towards -infinity */ 75 DEC_ROUND_05UP, /* round for reround */ 76 DEC_ROUND_MAX /* enum must be less than this */ 77 }; 78 #define DEC_ROUND_DEFAULT DEC_ROUND_HALF_EVEN; 79 80 typedef struct { 81 int32_t digits; /* working precision */ 82 int32_t emax; /* maximum positive exponent */ 83 int32_t emin; /* minimum negative exponent */ 84 enum rounding round; /* rounding mode */ 85 uint32_t traps; /* trap-enabler flags */ 86 uint32_t status; /* status flags */ 87 uint8_t clamp; /* flag: apply IEEE exponent clamp */ 88 #if DECSUBSET 89 uint8_t extended; /* flag: special-values allowed */ 90 #endif 91 } decContext; 92 93 /* Maxima and Minima for context settings */ 94 #define DEC_MAX_DIGITS 999999999 95 #define DEC_MIN_DIGITS 1 96 #define DEC_MAX_EMAX 999999999 97 #define DEC_MIN_EMAX 0 98 #define DEC_MAX_EMIN 0 99 #define DEC_MIN_EMIN -999999999 100 #define DEC_MAX_MATH 999999 /* max emax, etc., for math funcs. */ 101 102 /* Classifications for decimal numbers, aligned with 754r (note */ 103 /* that 'normal' and 'subnormal' are meaningful only with a */ 104 /* decContext or a fixed size format). */ 105 enum decClass { 106 DEC_CLASS_SNAN, 107 DEC_CLASS_QNAN, 108 DEC_CLASS_NEG_INF, 109 DEC_CLASS_NEG_NORMAL, 110 DEC_CLASS_NEG_SUBNORMAL, 111 DEC_CLASS_NEG_ZERO, 112 DEC_CLASS_POS_ZERO, 113 DEC_CLASS_POS_SUBNORMAL, 114 DEC_CLASS_POS_NORMAL, 115 DEC_CLASS_POS_INF 116 }; 117 /* Strings for the decClasses */ 118 #define DEC_ClassString_SN "sNaN" 119 #define DEC_ClassString_QN "NaN" 120 #define DEC_ClassString_NI "-Infinity" 121 #define DEC_ClassString_NN "-Normal" 122 #define DEC_ClassString_NS "-Subnormal" 123 #define DEC_ClassString_NZ "-Zero" 124 #define DEC_ClassString_PZ "+Zero" 125 #define DEC_ClassString_PS "+Subnormal" 126 #define DEC_ClassString_PN "+Normal" 127 #define DEC_ClassString_PI "+Infinity" 128 #define DEC_ClassString_UN "Invalid" 129 130 /* Trap-enabler and Status flags (exceptional conditions), and */ 131 /* their names. The top byte is reserved for internal use */ 132 #if DECEXTFLAG 133 /* Extended flags */ 134 #define DEC_Conversion_syntax 0x00000001 135 #define DEC_Division_by_zero 0x00000002 136 #define DEC_Division_impossible 0x00000004 137 #define DEC_Division_undefined 0x00000008 138 #define DEC_Insufficient_storage 0x00000010 /* [when malloc fails] */ 139 #define DEC_Inexact 0x00000020 140 #define DEC_Invalid_context 0x00000040 141 #define DEC_Invalid_operation 0x00000080 142 #if DECSUBSET 143 #define DEC_Lost_digits 0x00000100 144 #endif 145 #define DEC_Overflow 0x00000200 146 #define DEC_Clamped 0x00000400 147 #define DEC_Rounded 0x00000800 148 #define DEC_Subnormal 0x00001000 149 #define DEC_Underflow 0x00002000 150 #else 151 /* IEEE flags only */ 152 #define DEC_Conversion_syntax 0x00000010 153 #define DEC_Division_by_zero 0x00000002 154 #define DEC_Division_impossible 0x00000010 155 #define DEC_Division_undefined 0x00000010 156 #define DEC_Insufficient_storage 0x00000010 /* [when malloc fails] */ 157 #define DEC_Inexact 0x00000001 158 #define DEC_Invalid_context 0x00000010 159 #define DEC_Invalid_operation 0x00000010 160 #if DECSUBSET 161 #define DEC_Lost_digits 0x00000000 162 #endif 163 #define DEC_Overflow 0x00000008 164 #define DEC_Clamped 0x00000000 165 #define DEC_Rounded 0x00000000 166 #define DEC_Subnormal 0x00000000 167 #define DEC_Underflow 0x00000004 168 #endif 169 170 /* IEEE 854 groupings for the flags */ 171 /* [DEC_Clamped, DEC_Lost_digits, DEC_Rounded, and DEC_Subnormal */ 172 /* are not in IEEE 854] */ 173 #define DEC_IEEE_854_Division_by_zero (DEC_Division_by_zero) 174 #if DECSUBSET 175 #define DEC_IEEE_854_Inexact (DEC_Inexact | DEC_Lost_digits) 176 #else 177 #define DEC_IEEE_854_Inexact (DEC_Inexact) 178 #endif 179 #define DEC_IEEE_854_Invalid_operation (DEC_Conversion_syntax | \ 180 DEC_Division_impossible | \ 181 DEC_Division_undefined | \ 182 DEC_Insufficient_storage | \ 183 DEC_Invalid_context | \ 184 DEC_Invalid_operation) 185 #define DEC_IEEE_854_Overflow (DEC_Overflow) 186 #define DEC_IEEE_854_Underflow (DEC_Underflow) 187 188 /* flags which are normally errors (result is qNaN, infinite, or 0) */ 189 #define DEC_Errors (DEC_IEEE_854_Division_by_zero | \ 190 DEC_IEEE_854_Invalid_operation | \ 191 DEC_IEEE_854_Overflow | DEC_IEEE_854_Underflow) 192 /* flags which cause a result to become qNaN */ 193 #define DEC_NaNs DEC_IEEE_854_Invalid_operation 194 195 /* flags which are normally for information only (finite results) */ 196 #if DECSUBSET 197 #define DEC_Information (DEC_Clamped | DEC_Rounded | DEC_Inexact \ 198 | DEC_Lost_digits) 199 #else 200 #define DEC_Information (DEC_Clamped | DEC_Rounded | DEC_Inexact) 201 #endif 202 203 /* Name strings for the exceptional conditions */ 204 #define DEC_Condition_CS "Conversion syntax" 205 #define DEC_Condition_DZ "Division by zero" 206 #define DEC_Condition_DI "Division impossible" 207 #define DEC_Condition_DU "Division undefined" 208 #define DEC_Condition_IE "Inexact" 209 #define DEC_Condition_IS "Insufficient storage" 210 #define DEC_Condition_IC "Invalid context" 211 #define DEC_Condition_IO "Invalid operation" 212 #if DECSUBSET 213 #define DEC_Condition_LD "Lost digits" 214 #endif 215 #define DEC_Condition_OV "Overflow" 216 #define DEC_Condition_PA "Clamped" 217 #define DEC_Condition_RO "Rounded" 218 #define DEC_Condition_SU "Subnormal" 219 #define DEC_Condition_UN "Underflow" 220 #define DEC_Condition_ZE "No status" 221 #define DEC_Condition_MU "Multiple status" 222 #define DEC_Condition_Length 21 /* length of the longest string, */ 223 /* including terminator */ 224 225 /* Initialization descriptors, used by decContextDefault */ 226 #define DEC_INIT_BASE 0 227 #define DEC_INIT_DECIMAL32 32 228 #define DEC_INIT_DECIMAL64 64 229 #define DEC_INIT_DECIMAL128 128 230 /* Synonyms */ 231 #define DEC_INIT_DECSINGLE DEC_INIT_DECIMAL32 232 #define DEC_INIT_DECDOUBLE DEC_INIT_DECIMAL64 233 #define DEC_INIT_DECQUAD DEC_INIT_DECIMAL128 234 235 /* decContext routines */ 236 237 238 extern decContext * decContextClearStatus(decContext *, uint32_t); 239 extern decContext * decContextDefault(decContext *, int32_t); 240 extern enum rounding decContextGetRounding(decContext *); 241 extern uint32_t decContextGetStatus(decContext *); 242 extern decContext * decContextRestoreStatus(decContext *, uint32_t, uint32_t); 243 extern uint32_t decContextSaveStatus(decContext *, uint32_t); 244 extern decContext * decContextSetRounding(decContext *, enum rounding); 245 extern decContext * decContextSetStatus(decContext *, uint32_t); 246 extern decContext * decContextSetStatusFromString(decContext *, const char *); 247 extern decContext * decContextSetStatusFromStringQuiet(decContext *, const char *); 248 extern decContext * decContextSetStatusQuiet(decContext *, uint32_t); 249 extern const char * decContextStatusToString(const decContext *); 250 extern uint32_t decContextTestSavedStatus(uint32_t, uint32_t); 251 extern uint32_t decContextTestStatus(decContext *, uint32_t); 252 extern decContext * decContextZeroStatus(decContext *); 253 254 #endif 255