1 | /* Decimal context header module for the decNumber C Library. |
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2 | Copyright (C) 2005-2017 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 3, or (at your option) any later |

10 | version. |

11 | |

12 | GCC is distributed in the hope that it will be useful, but WITHOUT ANY |

13 | WARRANTY; without even the implied warranty of MERCHANTABILITY or |

14 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |

15 | for more details. |

16 | |

17 | Under Section 7 of GPL version 3, you are granted additional |

18 | permissions described in the GCC Runtime Library Exception, version |

19 | 3.1, as published by the Free Software Foundation. |

20 | |

21 | You should have received a copy of the GNU General Public License and |

22 | a copy of the GCC Runtime Library Exception along with this program; |

23 | see the files COPYING3 and COPYING.RUNTIME respectively. If not, see |

24 | <http://www.gnu.org/licenses/>. */ |

25 | |

26 | /* ------------------------------------------------------------------ */ |

27 | /* Decimal Context module header */ |

28 | /* ------------------------------------------------------------------ */ |

29 | /* */ |

30 | /* Context variables must always have valid values: */ |

31 | /* */ |

32 | /* status -- [any bits may be cleared, but not set, by user] */ |

33 | /* round -- must be one of the enumerated rounding modes */ |

34 | /* */ |

35 | /* The following variables are implied for fixed size formats (i.e., */ |

36 | /* they are ignored) but should still be set correctly in case used */ |

37 | /* with decNumber functions: */ |

38 | /* */ |

39 | /* clamp -- must be either 0 or 1 */ |

40 | /* digits -- must be in the range 1 through 999999999 */ |

41 | /* emax -- must be in the range 0 through 999999999 */ |

42 | /* emin -- must be in the range 0 through -999999999 */ |

43 | /* extended -- must be either 0 or 1 [present only if DECSUBSET] */ |

44 | /* traps -- only defined bits may be set */ |

45 | /* */ |

46 | /* ------------------------------------------------------------------ */ |

47 | |

48 | #if !defined(DECCONTEXT) |

49 | #define DECCONTEXT |

50 | #define DECCNAME "decContext" /* Short name */ |

51 | #define DECCFULLNAME "Decimal Context Descriptor" /* Verbose name */ |

52 | #define DECCAUTHOR "Mike Cowlishaw" /* Who to blame */ |

53 | |

54 | #include "gstdint.h" /* C99 standard integers */ |

55 | #include <stdio.h> /* for printf, etc. */ |

56 | #include <signal.h> /* for traps */ |

57 | |

58 | /* Extended flags setting -- set this to 0 to use only IEEE flags */ |

59 | #if !defined(DECEXTFLAG) |

60 | #define DECEXTFLAG 1 /* 1=enable extended flags */ |

61 | #endif |

62 | |

63 | /* Conditional code flag -- set this to 0 for best performance */ |

64 | #if !defined(DECSUBSET) |

65 | #define DECSUBSET 0 /* 1=enable subset arithmetic */ |

66 | #endif |

67 | |

68 | /* Context for operations, with associated constants */ |

69 | enum rounding { |

70 | DEC_ROUND_CEILING, /* round towards +infinity */ |

71 | DEC_ROUND_UP, /* round away from 0 */ |

72 | DEC_ROUND_HALF_UP, /* 0.5 rounds up */ |

73 | DEC_ROUND_HALF_EVEN, /* 0.5 rounds to nearest even */ |

74 | DEC_ROUND_HALF_DOWN, /* 0.5 rounds down */ |

75 | DEC_ROUND_DOWN, /* round towards 0 (truncate) */ |

76 | DEC_ROUND_FLOOR, /* round towards -infinity */ |

77 | DEC_ROUND_05UP, /* round for reround */ |

78 | DEC_ROUND_MAX /* enum must be less than this */ |

79 | }; |

80 | #define DEC_ROUND_DEFAULT DEC_ROUND_HALF_EVEN; |

81 | |

82 | typedef struct { |

83 | int32_t digits; /* working precision */ |

84 | int32_t emax; /* maximum positive exponent */ |

85 | int32_t emin; /* minimum negative exponent */ |

86 | enum rounding round; /* rounding mode */ |

87 | uint32_t traps; /* trap-enabler flags */ |

88 | uint32_t status; /* status flags */ |

89 | uint8_t clamp; /* flag: apply IEEE exponent clamp */ |

90 | #if DECSUBSET |

91 | uint8_t extended; /* flag: special-values allowed */ |

92 | #endif |

93 | } decContext; |

94 | |

95 | /* Maxima and Minima for context settings */ |

96 | #define DEC_MAX_DIGITS 999999999 |

97 | #define DEC_MIN_DIGITS 1 |

98 | #define DEC_MAX_EMAX 999999999 |

99 | #define DEC_MIN_EMAX 0 |

100 | #define DEC_MAX_EMIN 0 |

101 | #define DEC_MIN_EMIN -999999999 |

102 | #define DEC_MAX_MATH 999999 /* max emax, etc., for math funcs. */ |

103 | |

104 | /* Classifications for decimal numbers, aligned with 754 (note that */ |

105 | /* 'normal' and 'subnormal' are meaningful only with a decContext */ |

106 | /* or a fixed size format). */ |

107 | enum decClass { |

108 | DEC_CLASS_SNAN, |

109 | DEC_CLASS_QNAN, |

110 | DEC_CLASS_NEG_INF, |

111 | DEC_CLASS_NEG_NORMAL, |

112 | DEC_CLASS_NEG_SUBNORMAL, |

113 | DEC_CLASS_NEG_ZERO, |

114 | DEC_CLASS_POS_ZERO, |

115 | DEC_CLASS_POS_SUBNORMAL, |

116 | DEC_CLASS_POS_NORMAL, |

117 | DEC_CLASS_POS_INF |

118 | }; |

119 | /* Strings for the decClasses */ |

120 | #define DEC_ClassString_SN "sNaN" |

121 | #define DEC_ClassString_QN "NaN" |

122 | #define DEC_ClassString_NI "-Infinity" |

123 | #define DEC_ClassString_NN "-Normal" |

124 | #define DEC_ClassString_NS "-Subnormal" |

125 | #define DEC_ClassString_NZ "-Zero" |

126 | #define DEC_ClassString_PZ "+Zero" |

127 | #define DEC_ClassString_PS "+Subnormal" |

128 | #define DEC_ClassString_PN "+Normal" |

129 | #define DEC_ClassString_PI "+Infinity" |

130 | #define DEC_ClassString_UN "Invalid" |

131 | |

132 | /* Trap-enabler and Status flags (exceptional conditions), and */ |

133 | /* their names. The top byte is reserved for internal use */ |

134 | #if DECEXTFLAG |

135 | /* Extended flags */ |

136 | #define DEC_Conversion_syntax 0x00000001 |

137 | #define DEC_Division_by_zero 0x00000002 |

138 | #define DEC_Division_impossible 0x00000004 |

139 | #define DEC_Division_undefined 0x00000008 |

140 | #define DEC_Insufficient_storage 0x00000010 /* [when malloc fails] */ |

141 | #define DEC_Inexact 0x00000020 |

142 | #define DEC_Invalid_context 0x00000040 |

143 | #define DEC_Invalid_operation 0x00000080 |

144 | #if DECSUBSET |

145 | #define DEC_Lost_digits 0x00000100 |

146 | #endif |

147 | #define DEC_Overflow 0x00000200 |

148 | #define DEC_Clamped 0x00000400 |

149 | #define DEC_Rounded 0x00000800 |

150 | #define DEC_Subnormal 0x00001000 |

151 | #define DEC_Underflow 0x00002000 |

152 | #else |

153 | /* IEEE flags only */ |

154 | #define DEC_Conversion_syntax 0x00000010 |

155 | #define DEC_Division_by_zero 0x00000002 |

156 | #define DEC_Division_impossible 0x00000010 |

157 | #define DEC_Division_undefined 0x00000010 |

158 | #define DEC_Insufficient_storage 0x00000010 /* [when malloc fails] */ |

159 | #define DEC_Inexact 0x00000001 |

160 | #define DEC_Invalid_context 0x00000010 |

161 | #define DEC_Invalid_operation 0x00000010 |

162 | #if DECSUBSET |

163 | #define DEC_Lost_digits 0x00000000 |

164 | #endif |

165 | #define DEC_Overflow 0x00000008 |

166 | #define DEC_Clamped 0x00000000 |

167 | #define DEC_Rounded 0x00000000 |

168 | #define DEC_Subnormal 0x00000000 |

169 | #define DEC_Underflow 0x00000004 |

170 | #endif |

171 | |

172 | /* IEEE 754 groupings for the flags */ |

173 | /* [DEC_Clamped, DEC_Lost_digits, DEC_Rounded, and DEC_Subnormal */ |

174 | /* are not in IEEE 754] */ |

175 | #define DEC_IEEE_754_Division_by_zero (DEC_Division_by_zero) |

176 | #if DECSUBSET |

177 | #define DEC_IEEE_754_Inexact (DEC_Inexact | DEC_Lost_digits) |

178 | #else |

179 | #define DEC_IEEE_754_Inexact (DEC_Inexact) |

180 | #endif |

181 | #define DEC_IEEE_754_Invalid_operation (DEC_Conversion_syntax | \ |

182 | DEC_Division_impossible | \ |

183 | DEC_Division_undefined | \ |

184 | DEC_Insufficient_storage | \ |

185 | DEC_Invalid_context | \ |

186 | DEC_Invalid_operation) |

187 | #define DEC_IEEE_754_Overflow (DEC_Overflow) |

188 | #define DEC_IEEE_754_Underflow (DEC_Underflow) |

189 | |

190 | /* flags which are normally errors (result is qNaN, infinite, or 0) */ |

191 | #define DEC_Errors (DEC_IEEE_754_Division_by_zero | \ |

192 | DEC_IEEE_754_Invalid_operation | \ |

193 | DEC_IEEE_754_Overflow | DEC_IEEE_754_Underflow) |

194 | /* flags which cause a result to become qNaN */ |

195 | #define DEC_NaNs DEC_IEEE_754_Invalid_operation |

196 | |

197 | /* flags which are normally for information only (finite results) */ |

198 | #if DECSUBSET |

199 | #define DEC_Information (DEC_Clamped | DEC_Rounded | DEC_Inexact \ |

200 | | DEC_Lost_digits) |

201 | #else |

202 | #define DEC_Information (DEC_Clamped | DEC_Rounded | DEC_Inexact) |

203 | #endif |

204 | |

205 | /* IEEE 854 names (for compatibility with older decNumber versions) */ |

206 | #define DEC_IEEE_854_Division_by_zero DEC_IEEE_754_Division_by_zero |

207 | #define DEC_IEEE_854_Inexact DEC_IEEE_754_Inexact |

208 | #define DEC_IEEE_854_Invalid_operation DEC_IEEE_754_Invalid_operation |

209 | #define DEC_IEEE_854_Overflow DEC_IEEE_754_Overflow |

210 | #define DEC_IEEE_854_Underflow DEC_IEEE_754_Underflow |

211 | |

212 | /* Name strings for the exceptional conditions */ |

213 | #define DEC_Condition_CS "Conversion syntax" |

214 | #define DEC_Condition_DZ "Division by zero" |

215 | #define DEC_Condition_DI "Division impossible" |

216 | #define DEC_Condition_DU "Division undefined" |

217 | #define DEC_Condition_IE "Inexact" |

218 | #define DEC_Condition_IS "Insufficient storage" |

219 | #define DEC_Condition_IC "Invalid context" |

220 | #define DEC_Condition_IO "Invalid operation" |

221 | #if DECSUBSET |

222 | #define DEC_Condition_LD "Lost digits" |

223 | #endif |

224 | #define DEC_Condition_OV "Overflow" |

225 | #define DEC_Condition_PA "Clamped" |

226 | #define DEC_Condition_RO "Rounded" |

227 | #define DEC_Condition_SU "Subnormal" |

228 | #define DEC_Condition_UN "Underflow" |

229 | #define DEC_Condition_ZE "No status" |

230 | #define DEC_Condition_MU "Multiple status" |

231 | #define DEC_Condition_Length 21 /* length of the longest string, */ |

232 | /* including terminator */ |

233 | |

234 | /* Initialization descriptors, used by decContextDefault */ |

235 | #define DEC_INIT_BASE 0 |

236 | #define DEC_INIT_DECIMAL32 32 |

237 | #define DEC_INIT_DECIMAL64 64 |

238 | #define DEC_INIT_DECIMAL128 128 |

239 | /* Synonyms */ |

240 | #define DEC_INIT_DECSINGLE DEC_INIT_DECIMAL32 |

241 | #define DEC_INIT_DECDOUBLE DEC_INIT_DECIMAL64 |

242 | #define DEC_INIT_DECQUAD DEC_INIT_DECIMAL128 |

243 | |

244 | /* decContext routines */ |

245 | |

246 | #include "decContextSymbols.h" |

247 | |

248 | #ifdef __cplusplus |

249 | extern "C"{ |

250 | #endif |

251 | |

252 | extern decContext * decContextClearStatus(decContext *, uint32_t); |

253 | extern decContext * decContextDefault(decContext *, int32_t); |

254 | extern enum rounding decContextGetRounding(decContext *); |

255 | extern uint32_t decContextGetStatus(decContext *); |

256 | extern decContext * decContextRestoreStatus(decContext *, uint32_t, uint32_t); |

257 | extern uint32_t decContextSaveStatus(decContext *, uint32_t); |

258 | extern decContext * decContextSetRounding(decContext *, enum rounding); |

259 | extern decContext * decContextSetStatus(decContext *, uint32_t); |

260 | extern decContext * decContextSetStatusFromString(decContext *, const char *); |

261 | extern decContext * decContextSetStatusFromStringQuiet(decContext *, const char *); |

262 | extern decContext * decContextSetStatusQuiet(decContext *, uint32_t); |

263 | extern const char * decContextStatusToString(const decContext *); |

264 | extern int32_t decContextTestEndian(uint8_t); |

265 | extern uint32_t decContextTestSavedStatus(uint32_t, uint32_t); |

266 | extern uint32_t decContextTestStatus(decContext *, uint32_t); |

267 | extern decContext * decContextZeroStatus(decContext *); |

268 | |

269 | #ifdef __cplusplus |

270 | } |

271 | #endif |

272 | |

273 | #endif |

274 |