gcc/libdecnumber/decimal128.h
2005-11-29 09:30:30 +11:00

114 lines
4.4 KiB
C

/* Decimal 128-bit format 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. */
#if !defined(DECIMAL128)
#define DECIMAL128
#define DEC128NAME "decimal128" /* Short name */
#define DEC128FULLNAME "Decimal 128-bit Number" /* Verbose name */
#define DEC128AUTHOR "Mike Cowlishaw" /* Who to blame */
#if defined(DECIMAL32)
#error decimal128.h must precede decimal32.h for correct DECNUMDIGITS
#else
#if defined(DECIMAL64)
#error decimal128.h must precede decimal64.h for correct DECNUMDIGITS
#endif
#endif
/* parameters for decimal128s */
#define DECIMAL128_Bytes 16 /* length */
#define DECIMAL128_Pmax 34 /* maximum precision (digits) */
#define DECIMAL128_Emax 6144 /* maximum adjusted exponent */
#define DECIMAL128_Emin -6143 /* minimum adjusted exponent */
#define DECIMAL128_Bias 6176 /* bias for the exponent */
#define DECIMAL128_String 43 /* maximum string length, +1 */
/* highest biased exponent (Elimit-1) */
#define DECIMAL128_Ehigh (DECIMAL128_Emax+DECIMAL128_Bias-DECIMAL128_Pmax+1)
#ifndef DECNUMDIGITS
#define DECNUMDIGITS DECIMAL128_Pmax /* size if not already defined */
#endif
#ifndef DECNUMBER
#include "decNumber.h" /* context and number library */
#endif
/* Decimal 128-bit type, accessible by bytes */
typedef struct
{
uint8_t bytes[DECIMAL128_Bytes]; /* decimal128: 1, 5, 12, 110 bits */
} decimal128;
/* special values [top byte excluding sign bit; last two bits are
don't-care for Infinity on input, last bit don't-care for NaN] */
#if !defined(DECIMAL_NaN)
#define DECIMAL_NaN 0x7c /* 0 11111 00 NaN */
#define DECIMAL_sNaN 0x7e /* 0 11111 10 sNaN */
#define DECIMAL_Inf 0x78 /* 0 11110 00 Infinity */
#endif
/* Macros for accessing decimal128 fields. These assume the argument
is a reference (pointer) to the decimal128 structure */
/* Get sign */
#define decimal128Sign(d) ((unsigned)(d)->bytes[0]>>7)
/* Get combination field */
#define decimal128Comb(d) (((d)->bytes[0] & 0x7c)>>2)
/* Get exponent continuation [does not remove bias] */
#define decimal128ExpCon(d) ((((d)->bytes[0] & 0x03)<<10) \
| ((unsigned)(d)->bytes[1]<<2) \
| ((unsigned)(d)->bytes[2]>>6))
/* Set sign [this assumes sign previously 0] */
#define decimal128SetSign(d, b) { \
(d)->bytes[0]|=((unsigned)(b)<<7);}
/* Set exponent continuation [does not apply bias] */
/* This assumes range has been checked and exponent previously 0; */
/* type of exponent must be unsigned */
#define decimal128SetExpCon(d, e) { \
(d)->bytes[0]|=(uint8_t)((e)>>10); \
(d)->bytes[1] =(uint8_t)(((e)&0x3fc)>>2); \
(d)->bytes[2]|=(uint8_t)(((e)&0x03)<<6);}
/* ------------------------------------------------------------------ */
/* Routines */
/* ------------------------------------------------------------------ */
#ifdef IN_LIBGCC2
#define decimal128FromString __decimal128FromString
#define decimal128ToString __decimal128ToString
#define decimal128ToEngString __decimal128ToEngString
#define decimal128FromNumber __decimal128FromNumber
#define decimal128ToNumber __decimal128ToNumber
#endif
/* String conversions */
decimal128 *decimal128FromString (decimal128 *, char *, decContext *);
char *decimal128ToString (decimal128 *, char *);
char *decimal128ToEngString (decimal128 *, char *);
/* decNumber conversions */
decimal128 *decimal128FromNumber (decimal128 *, decNumber *, decContext *);
decNumber *decimal128ToNumber (decimal128 *, decNumber *);
#endif