1 /* Decimal Context module header for the decNumber C Library 2 Copyright (C) 2005, 2006 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 /* */ 33 /* Context must always be set correctly: */ 34 /* */ 35 /* digits -- must be in the range 1 through 999999999 */ 36 /* emax -- must be in the range 0 through 999999999 */ 37 /* emin -- must be in the range 0 through -999999999 */ 38 /* round -- must be one of the enumerated rounding modes */ 39 /* traps -- only defined bits may be set */ 40 /* status -- [any bits may be cleared, but not set, by user] */ 41 /* clamp -- must be either 0 or 1 */ 42 /* extended -- must be either 0 or 1 [present only if DECSUBSET] */ 43 /* */ 44 /* ------------------------------------------------------------------ */ 45 46 #if !defined(DECCONTEXT) 47 #define DECCONTEXT 48 #define DECCNAME "decContext" /* Short name */ 49 #define DECCFULLNAME "Decimal Context Descriptor" /* Verbose name */ 50 #define DECCAUTHOR "Mike Cowlishaw" /* Who to blame */ 51 52 #include "gstdint.h" /* C99 standard integers */ 53 #include <signal.h> /* for traps */ 54 55 56 /* Conditional code flag -- set this to 0 for best performance */ 57 #define DECSUBSET 0 /* 1 to enable subset arithmetic */ 58 59 /* Context for operations, with associated constants */ 60 enum rounding 61 { 62 DEC_ROUND_CEILING, /* round towards +infinity */ 63 DEC_ROUND_UP, /* round away from 0 */ 64 DEC_ROUND_HALF_UP, /* 0.5 rounds up */ 65 DEC_ROUND_HALF_EVEN, /* 0.5 rounds to nearest even */ 66 DEC_ROUND_HALF_DOWN, /* 0.5 rounds down */ 67 DEC_ROUND_DOWN, /* round towards 0 (truncate) */ 68 DEC_ROUND_FLOOR, /* round towards -infinity */ 69 DEC_ROUND_MAX /* enum must be less than this */ 70 }; 71 72 typedef struct 73 { 74 int32_t digits; /* working precision */ 75 int32_t emax; /* maximum positive exponent */ 76 int32_t emin; /* minimum negative exponent */ 77 enum rounding round; /* rounding mode */ 78 uint32_t traps; /* trap-enabler flags */ 79 uint32_t status; /* status flags */ 80 uint8_t clamp; /* flag: apply IEEE exponent clamp */ 81 #if DECSUBSET 82 uint8_t extended; /* flag: special-values allowed */ 83 #endif 84 } decContext; 85 86 /* Maxima and Minima */ 87 #define DEC_MAX_DIGITS 999999999 88 #define DEC_MIN_DIGITS 1 89 #define DEC_MAX_EMAX 999999999 90 #define DEC_MIN_EMAX 0 91 #define DEC_MAX_EMIN 0 92 #define DEC_MIN_EMIN -999999999 93 94 /* Trap-enabler and Status flags (exceptional conditions), and their names */ 95 /* Top byte is reserved for internal use */ 96 #define DEC_Conversion_syntax 0x00000001 97 #define DEC_Division_by_zero 0x00000002 98 #define DEC_Division_impossible 0x00000004 99 #define DEC_Division_undefined 0x00000008 100 #define DEC_Insufficient_storage 0x00000010 /* [used if malloc fails] */ 101 #define DEC_Inexact 0x00000020 102 #define DEC_Invalid_context 0x00000040 103 #define DEC_Invalid_operation 0x00000080 104 #if DECSUBSET 105 #define DEC_Lost_digits 0x00000100 106 #endif 107 #define DEC_Overflow 0x00000200 108 #define DEC_Clamped 0x00000400 109 #define DEC_Rounded 0x00000800 110 #define DEC_Subnormal 0x00001000 111 #define DEC_Underflow 0x00002000 112 113 /* IEEE 854 groupings for the flags */ 114 /* [DEC_Clamped, DEC_Lost_digits, DEC_Rounded, and DEC_Subnormal are */ 115 /* not in IEEE 854] */ 116 #define DEC_IEEE_854_Division_by_zero (DEC_Division_by_zero) 117 #if DECSUBSET 118 #define DEC_IEEE_854_Inexact (DEC_Inexact | DEC_Lost_digits) 119 #else 120 #define DEC_IEEE_854_Inexact (DEC_Inexact) 121 #endif 122 #define DEC_IEEE_854_Invalid_operation (DEC_Conversion_syntax | \ 123 DEC_Division_impossible | \ 124 DEC_Division_undefined | \ 125 DEC_Insufficient_storage | \ 126 DEC_Invalid_context | \ 127 DEC_Invalid_operation) 128 #define DEC_IEEE_854_Overflow (DEC_Overflow) 129 #define DEC_IEEE_854_Underflow (DEC_Underflow) 130 131 /* flags which are normally errors (results are qNaN, infinite, or 0) */ 132 #define DEC_Errors (DEC_IEEE_854_Division_by_zero | \ 133 DEC_IEEE_854_Invalid_operation | \ 134 DEC_IEEE_854_Overflow | DEC_IEEE_854_Underflow) 135 /* flags which cause a result to become qNaN */ 136 #define DEC_NaNs DEC_IEEE_854_Invalid_operation 137 138 /* flags which are normally for information only (have finite results) */ 139 #if DECSUBSET 140 #define DEC_Information (DEC_Clamped | DEC_Rounded | DEC_Inexact \ 141 | DEC_Lost_digits) 142 #else 143 #define DEC_Information (DEC_Clamped | DEC_Rounded | DEC_Inexact) 144 #endif 145 146 /* name strings for the exceptional conditions */ 147 148 #define DEC_Condition_CS "Conversion syntax" 149 #define DEC_Condition_DZ "Division by zero" 150 #define DEC_Condition_DI "Division impossible" 151 #define DEC_Condition_DU "Division undefined" 152 #define DEC_Condition_IE "Inexact" 153 #define DEC_Condition_IS "Insufficient storage" 154 #define DEC_Condition_IC "Invalid context" 155 #define DEC_Condition_IO "Invalid operation" 156 #if DECSUBSET 157 #define DEC_Condition_LD "Lost digits" 158 #endif 159 #define DEC_Condition_OV "Overflow" 160 #define DEC_Condition_PA "Clamped" 161 #define DEC_Condition_RO "Rounded" 162 #define DEC_Condition_SU "Subnormal" 163 #define DEC_Condition_UN "Underflow" 164 #define DEC_Condition_ZE "No status" 165 #define DEC_Condition_MU "Multiple status" 166 #define DEC_Condition_Length 21 /* length of the longest string, */ 167 /* including terminator */ 168 169 /* Initialization descriptors, used by decContextDefault */ 170 #define DEC_INIT_BASE 0 171 #define DEC_INIT_DECIMAL32 32 172 #define DEC_INIT_DECIMAL64 64 173 #define DEC_INIT_DECIMAL128 128 174 175 /* decContext routines */ 176 #ifdef IN_LIBGCC2 177 #define decContextDefault __decContextDefault 178 #define decContextSetStatus __decContextSetStatus 179 #define decContextStatusToString __decContextStatusToString 180 #define decContextSetStatusFromString __decContextSetStatusFromString 181 #endif 182 decContext *decContextDefault (decContext *, int32_t); 183 decContext *decContextSetStatus (decContext *, uint32_t); 184 const char *decContextStatusToString (const decContext *); 185 decContext *decContextSetStatusFromString (decContext *, const char *); 186 187 #endif 188