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/* Decimal Context module header for the decNumber C Library
Copyright (C) 2005 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.
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, 59 Temple Place - Suite 330, Boston, MA
02111-1307, USA. */
/* ------------------------------------------------------------------ */
/* */
/* Context must always be set correctly: */
/* */
/* 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 */
/* round -- must be one of the enumerated rounding modes */
/* traps -- only defined bits may be set */
/* status -- [any bits may be cleared, but not set, by user] */
/* clamp -- must be either 0 or 1 */
/* extended -- must be either 0 or 1 [present only if DECSUBSET] */
/* */
/* ------------------------------------------------------------------ */
#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 <stdint.h> /* C99 standard integers */
#include <signal.h> /* for traps */
/* Conditional code flag -- set this to 0 for best performance */
#define DECSUBSET 0 /* 1 to 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_MAX /* enum must be less than this */
};
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 */
#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
/* Trap-enabler and Status flags (exceptional conditions), and their names */
/* Top byte is reserved for internal use */
#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 /* [used if 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
/* 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 (results are 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 (have 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
/* decContext routines */
#ifdef IN_LIBGCC2
#define decContextDefault __decContextDefault
#define decContextSetStatus __decContextSetStatus
#define decContextStatusToString __decContextStatusToString
#define decContextSetStatusFromString __decContextSetStatusFromString
#endif
decContext *decContextDefault (decContext *, int32_t);
decContext *decContextSetStatus (decContext *, uint32_t);
const char *decContextStatusToString (decContext *);
decContext *decContextSetStatusFromString (decContext *, char *);
#endif
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