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Diffstat (limited to 'libdecnumber/decContext.h')
| -rw-r--r-- | libdecnumber/decContext.h | 258 |
1 files changed, 258 insertions, 0 deletions
diff --git a/libdecnumber/decContext.h b/libdecnumber/decContext.h new file mode 100644 index 0000000..f80d03c --- /dev/null +++ b/libdecnumber/decContext.h @@ -0,0 +1,258 @@ +/* Decimal context header module for the decNumber C Library. + Copyright (C) 2005, 2007 Free Software Foundation, Inc. + Contributed by IBM Corporation. Author Mike Cowlishaw. + + This file is part of GCC. + + GCC is free software; you can redistribute it and/or modify it under + the terms of the GNU General Public License as published by the Free + Software Foundation; either version 2, or (at your option) any later + version. + + In addition to the permissions in the GNU General Public License, + the Free Software Foundation gives you unlimited permission to link + the compiled version of this file into combinations with other + programs, and to distribute those combinations without any + restriction coming from the use of this file. (The General Public + License restrictions do apply in other respects; for example, they + cover modification of the file, and distribution when not linked + into a combine executable.) + + GCC is distributed in the hope that it will be useful, but WITHOUT ANY + WARRANTY; without even the implied warranty of MERCHANTABILITY or + FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License + for more details. + + You should have received a copy of the GNU General Public License + along with GCC; see the file COPYING. If not, write to the Free + Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA + 02110-1301, USA. */ + +/* ------------------------------------------------------------------ */ +/* Decimal Context module header */ +/* ------------------------------------------------------------------ */ +/* */ +/* Context variables must always have valid values: */ +/* */ +/* status -- [any bits may be cleared, but not set, by user] */ +/* round -- must be one of the enumerated rounding modes */ +/* */ +/* The following variables are implied for fixed size formats (i.e., */ +/* they are ignored) but should still be set correctly in case used */ +/* with decNumber functions: */ +/* */ +/* clamp -- must be either 0 or 1 */ +/* digits -- must be in the range 1 through 999999999 */ +/* emax -- must be in the range 0 through 999999999 */ +/* emin -- must be in the range 0 through -999999999 */ +/* extended -- must be either 0 or 1 [present only if DECSUBSET] */ +/* traps -- only defined bits may be set */ +/* */ +/* ------------------------------------------------------------------ */ + +#if !defined(DECCONTEXT) + #define DECCONTEXT + #define DECCNAME "decContext" /* Short name */ + #define DECCFULLNAME "Decimal Context Descriptor" /* Verbose name */ + #define DECCAUTHOR "Mike Cowlishaw" /* Who to blame */ + + #include "gstdint.h" /* C99 standard integers */ + #include <stdio.h> /* for printf, etc. */ + #include <signal.h> /* for traps */ + + /* Extended flags setting -- set this to 0 to use only IEEE flags */ + #define DECEXTFLAG 1 /* 1=enable extended flags */ + + /* Conditional code flag -- set this to 0 for best performance */ + #define DECSUBSET 0 /* 1=enable subset arithmetic */ + + /* Context for operations, with associated constants */ + enum rounding { + DEC_ROUND_CEILING, /* round towards +infinity */ + DEC_ROUND_UP, /* round away from 0 */ + DEC_ROUND_HALF_UP, /* 0.5 rounds up */ + DEC_ROUND_HALF_EVEN, /* 0.5 rounds to nearest even */ + DEC_ROUND_HALF_DOWN, /* 0.5 rounds down */ + DEC_ROUND_DOWN, /* round towards 0 (truncate) */ + DEC_ROUND_FLOOR, /* round towards -infinity */ + DEC_ROUND_05UP, /* round for reround */ + DEC_ROUND_MAX /* enum must be less than this */ + }; + #define DEC_ROUND_DEFAULT DEC_ROUND_HALF_EVEN; + + typedef struct { + int32_t digits; /* working precision */ + int32_t emax; /* maximum positive exponent */ + int32_t emin; /* minimum negative exponent */ + enum rounding round; /* rounding mode */ + uint32_t traps; /* trap-enabler flags */ + uint32_t status; /* status flags */ + uint8_t clamp; /* flag: apply IEEE exponent clamp */ + #if DECSUBSET + uint8_t extended; /* flag: special-values allowed */ + #endif + } decContext; + + /* Maxima and Minima for context settings */ + #define DEC_MAX_DIGITS 999999999 + #define DEC_MIN_DIGITS 1 + #define DEC_MAX_EMAX 999999999 + #define DEC_MIN_EMAX 0 + #define DEC_MAX_EMIN 0 + #define DEC_MIN_EMIN -999999999 + #define DEC_MAX_MATH 999999 /* max emax, etc., for math funcs. */ + + /* Classifications for decimal numbers, aligned with 754r (note */ + /* that 'normal' and 'subnormal' are meaningful only with a */ + /* decContext or a fixed size format). */ + enum decClass { + DEC_CLASS_SNAN, + DEC_CLASS_QNAN, + DEC_CLASS_NEG_INF, + DEC_CLASS_NEG_NORMAL, + DEC_CLASS_NEG_SUBNORMAL, + DEC_CLASS_NEG_ZERO, + DEC_CLASS_POS_ZERO, + DEC_CLASS_POS_SUBNORMAL, + DEC_CLASS_POS_NORMAL, + DEC_CLASS_POS_INF + }; + /* Strings for the decClasses */ + #define DEC_ClassString_SN "sNaN" + #define DEC_ClassString_QN "NaN" + #define DEC_ClassString_NI "-Infinity" + #define DEC_ClassString_NN "-Normal" + #define DEC_ClassString_NS "-Subnormal" + #define DEC_ClassString_NZ "-Zero" + #define DEC_ClassString_PZ "+Zero" + #define DEC_ClassString_PS "+Subnormal" + #define DEC_ClassString_PN "+Normal" + #define DEC_ClassString_PI "+Infinity" + #define DEC_ClassString_UN "Invalid" + + /* Trap-enabler and Status flags (exceptional conditions), and */ + /* their names. The top byte is reserved for internal use */ + #if DECEXTFLAG + /* Extended flags */ + #define DEC_Conversion_syntax 0x00000001 + #define DEC_Division_by_zero 0x00000002 + #define DEC_Division_impossible 0x00000004 + #define DEC_Division_undefined 0x00000008 + #define DEC_Insufficient_storage 0x00000010 /* [when malloc fails] */ + #define DEC_Inexact 0x00000020 + #define DEC_Invalid_context 0x00000040 + #define DEC_Invalid_operation 0x00000080 + #if DECSUBSET + #define DEC_Lost_digits 0x00000100 + #endif + #define DEC_Overflow 0x00000200 + #define DEC_Clamped 0x00000400 + #define DEC_Rounded 0x00000800 + #define DEC_Subnormal 0x00001000 + #define DEC_Underflow 0x00002000 + #else + /* IEEE flags only */ + #define DEC_Conversion_syntax 0x00000010 + #define DEC_Division_by_zero 0x00000002 + #define DEC_Division_impossible 0x00000010 + #define DEC_Division_undefined 0x00000010 + #define DEC_Insufficient_storage 0x00000010 /* [when malloc fails] */ + #define DEC_Inexact 0x00000001 + #define DEC_Invalid_context 0x00000010 + #define DEC_Invalid_operation 0x00000010 + #if DECSUBSET + #define DEC_Lost_digits 0x00000000 + #endif + #define DEC_Overflow 0x00000008 + #define DEC_Clamped 0x00000000 + #define DEC_Rounded 0x00000000 + #define DEC_Subnormal 0x00000000 + #define DEC_Underflow 0x00000004 + #endif + + /* IEEE 854 groupings for the flags */ + /* [DEC_Clamped, DEC_Lost_digits, DEC_Rounded, and DEC_Subnormal */ + /* are not in IEEE 854] */ + #define DEC_IEEE_854_Division_by_zero (DEC_Division_by_zero) + #if DECSUBSET + #define DEC_IEEE_854_Inexact (DEC_Inexact | DEC_Lost_digits) + #else + #define DEC_IEEE_854_Inexact (DEC_Inexact) + #endif + #define DEC_IEEE_854_Invalid_operation (DEC_Conversion_syntax | \ + DEC_Division_impossible | \ + DEC_Division_undefined | \ + DEC_Insufficient_storage | \ + DEC_Invalid_context | \ + DEC_Invalid_operation) + #define DEC_IEEE_854_Overflow (DEC_Overflow) + #define DEC_IEEE_854_Underflow (DEC_Underflow) + + /* flags which are normally errors (result is qNaN, infinite, or 0) */ + #define DEC_Errors (DEC_IEEE_854_Division_by_zero | \ + DEC_IEEE_854_Invalid_operation | \ + DEC_IEEE_854_Overflow | DEC_IEEE_854_Underflow) + /* flags which cause a result to become qNaN */ + #define DEC_NaNs DEC_IEEE_854_Invalid_operation + + /* flags which are normally for information only (finite results) */ + #if DECSUBSET + #define DEC_Information (DEC_Clamped | DEC_Rounded | DEC_Inexact \ + | DEC_Lost_digits) + #else + #define DEC_Information (DEC_Clamped | DEC_Rounded | DEC_Inexact) + #endif + + /* Name strings for the exceptional conditions */ + #define DEC_Condition_CS "Conversion syntax" + #define DEC_Condition_DZ "Division by zero" + #define DEC_Condition_DI "Division impossible" + #define DEC_Condition_DU "Division undefined" + #define DEC_Condition_IE "Inexact" + #define DEC_Condition_IS "Insufficient storage" + #define DEC_Condition_IC "Invalid context" + #define DEC_Condition_IO "Invalid operation" + #if DECSUBSET + #define DEC_Condition_LD "Lost digits" + #endif + #define DEC_Condition_OV "Overflow" + #define DEC_Condition_PA "Clamped" + #define DEC_Condition_RO "Rounded" + #define DEC_Condition_SU "Subnormal" + #define DEC_Condition_UN "Underflow" + #define DEC_Condition_ZE "No status" + #define DEC_Condition_MU "Multiple status" + #define DEC_Condition_Length 21 /* length of the longest string, */ + /* including terminator */ + + /* Initialization descriptors, used by decContextDefault */ + #define DEC_INIT_BASE 0 + #define DEC_INIT_DECIMAL32 32 + #define DEC_INIT_DECIMAL64 64 + #define DEC_INIT_DECIMAL128 128 + /* Synonyms */ + #define DEC_INIT_DECSINGLE DEC_INIT_DECIMAL32 + #define DEC_INIT_DECDOUBLE DEC_INIT_DECIMAL64 + #define DEC_INIT_DECQUAD DEC_INIT_DECIMAL128 + + /* decContext routines */ + + #include "decContextSymbols.h" + + extern decContext * decContextClearStatus(decContext *, uint32_t); + extern decContext * decContextDefault(decContext *, int32_t); + extern enum rounding decContextGetRounding(decContext *); + extern uint32_t decContextGetStatus(decContext *); + extern decContext * decContextRestoreStatus(decContext *, uint32_t, uint32_t); + extern uint32_t decContextSaveStatus(decContext *, uint32_t); + extern decContext * decContextSetRounding(decContext *, enum rounding); + extern decContext * decContextSetStatus(decContext *, uint32_t); + extern decContext * decContextSetStatusFromString(decContext *, const char *); + extern decContext * decContextSetStatusFromStringQuiet(decContext *, const char *); + extern decContext * decContextSetStatusQuiet(decContext *, uint32_t); + extern const char * decContextStatusToString(const decContext *); + extern uint32_t decContextTestSavedStatus(uint32_t, uint32_t); + extern uint32_t decContextTestStatus(decContext *, uint32_t); + extern decContext * decContextZeroStatus(decContext *); + +#endif |