include/libdecnumber/dpd/decimal128.h

   1 /* Decimal 128-bit format module header for the decNumber C Library.
   2    Copyright (C) 2005, 2007 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 /* Decimal 128-bit format module header                               */
  33 /* ------------------------------------------------------------------ */
  34
  35 #ifndef DECIMAL128_H
  36 #define DECIMAL128_H
  37
  38   #define DEC128NAME     "decimal128"                 /* Short name   */
  39   #define DEC128FULLNAME "Decimal 128-bit Number"     /* Verbose name */
  40   #define DEC128AUTHOR   "Mike Cowlishaw"             /* Who to blame */
  41
  42   /* parameters for decimal128s */
  43   #define DECIMAL128_Bytes  16          /* length                     */
  44   #define DECIMAL128_Pmax   34          /* maximum precision (digits) */
  45   #define DECIMAL128_Emax   6144        /* maximum adjusted exponent  */
  46   #define DECIMAL128_Emin  -6143        /* minimum adjusted exponent  */
  47   #define DECIMAL128_Bias   6176        /* bias for the exponent      */
  48   #define DECIMAL128_String 43          /* maximum string length, +1  */
  49   #define DECIMAL128_EconL  12          /* exp. continuation length   */
  50   /* highest biased exponent (Elimit-1)                               */
  51   #define DECIMAL128_Ehigh  (DECIMAL128_Emax+DECIMAL128_Bias-DECIMAL128_Pmax+1)
  52
  53   /* check enough digits, if pre-defined                              */
  54   #if defined(DECNUMDIGITS)
  55     #if (DECNUMDIGITS<DECIMAL128_Pmax)
  56       #error decimal128.h needs pre-defined DECNUMDIGITS>=34 for safe use
  57     #endif
  58   #endif
  59
  60   #ifndef DECNUMDIGITS
  61     #define DECNUMDIGITS DECIMAL128_Pmax /* size if not already defined*/
  62   #endif
  63   #include "libdecnumber/decNumber.h"
  64
  65   /* Decimal 128-bit type, accessible by bytes                        */
  66   typedef struct {
  67     uint8_t bytes[DECIMAL128_Bytes]; /* decimal128: 1, 5, 12, 110 bits*/
  68     } decimal128;
  69
  70   /* special values [top byte excluding sign bit; last two bits are   */
  71   /* don't-care for Infinity on input, last bit don't-care for NaN]   */
  72   #if !defined(DECIMAL_NaN)
  73     #define DECIMAL_NaN     0x7c        /* 0 11111 00 NaN             */
  74     #define DECIMAL_sNaN    0x7e        /* 0 11111 10 sNaN            */
  75     #define DECIMAL_Inf     0x78        /* 0 11110 00 Infinity        */
  76   #endif
  77
  78   #include "decimal128Local.h"
  79
  80   /* ---------------------------------------------------------------- */
  81   /* Routines                                                         */
  82   /* ---------------------------------------------------------------- */
  83
  84
  85   /* String conversions                                               */
  86   decimal128 * decimal128FromString(decimal128 *, const char *, decContext *);
  87   char * decimal128ToString(const decimal128 *, char *);
  88   char * decimal128ToEngString(const decimal128 *, char *);
  89
  90   /* decNumber conversions                                            */
  91   decimal128 * decimal128FromNumber(decimal128 *, const decNumber *,
  92                                     decContext *);
  93   decNumber * decimal128ToNumber(const decimal128 *, decNumber *);
  94
  95   /* Format-dependent utilities                                       */
  96   uint32_t    decimal128IsCanonical(const decimal128 *);
  97   decimal128 * decimal128Canonical(decimal128 *, const decimal128 *);
  98
  99 #endif