libdecnumber/dpd/decimal128.h

   1 /* Decimal 128-bit format module header for the decNumber C Library.
   2    Copyright (C) 2005-2021 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 128-bit format module header                               */
  28 /* ------------------------------------------------------------------ */
  29
  30 #if !defined(DECIMAL128)
  31   #define DECIMAL128
  32   #define DEC128NAME     "decimal128"                 /* Short name   */
  33   #define DEC128FULLNAME "Decimal 128-bit Number"     /* Verbose name */
  34   #define DEC128AUTHOR   "Mike Cowlishaw"             /* Who to blame */
  35
  36   /* parameters for decimal128s */
  37   #define DECIMAL128_Bytes  16          /* length                     */
  38   #define DECIMAL128_Pmax   34          /* maximum precision (digits) */
  39   #define DECIMAL128_Emax   6144        /* maximum adjusted exponent  */
  40   #define DECIMAL128_Emin  -6143        /* minimum adjusted exponent  */
  41   #define DECIMAL128_Bias   6176        /* bias for the exponent      */
  42   #define DECIMAL128_String 43          /* maximum string length, +1  */
  43   #define DECIMAL128_EconL  12          /* exp. continuation length   */
  44   /* highest biased exponent (Elimit-1)                               */
  45   #define DECIMAL128_Ehigh  (DECIMAL128_Emax+DECIMAL128_Bias-DECIMAL128_Pmax+1)
  46
  47   /* check enough digits, if pre-defined                              */
  48   #if defined(DECNUMDIGITS)
  49     #if (DECNUMDIGITS<DECIMAL128_Pmax)
  50       #error decimal128.h needs pre-defined DECNUMDIGITS>=34 for safe use
  51     #endif
  52   #endif
  53
  54   #ifndef DECNUMDIGITS
  55     #define DECNUMDIGITS DECIMAL128_Pmax /* size if not already defined*/
  56   #endif
  57   #ifndef DECNUMBER
  58     #include "decNumber.h"              /* context and number library */
  59   #endif
  60
  61   /* Decimal 128-bit type, accessible by bytes                        */
  62   typedef struct {
  63     uint8_t bytes[DECIMAL128_Bytes]; /* decimal128: 1, 5, 12, 110 bits*/
  64     } decimal128;
  65
  66   /* special values [top byte excluding sign bit; last two bits are   */
  67   /* don't-care for Infinity on input, last bit don't-care for NaN]   */
  68   #if !defined(DECIMAL_NaN)
  69     #define DECIMAL_NaN     0x7c        /* 0 11111 00 NaN             */
  70     #define DECIMAL_sNaN    0x7e        /* 0 11111 10 sNaN            */
  71     #define DECIMAL_Inf     0x78        /* 0 11110 00 Infinity        */
  72   #endif
  73
  74 #include "decimal128Local.h"
  75
  76   /* ---------------------------------------------------------------- */
  77   /* Routines                                                         */
  78   /* ---------------------------------------------------------------- */
  79
  80 #include "decimal128Symbols.h"
  81
  82   #ifdef __cplusplus
  83   extern "C" {
  84   #endif
  85
  86   /* String conversions                                               */
  87   decimal128 * decimal128FromString(decimal128 *, const char *, decContext *);
  88   char * decimal128ToString(const decimal128 *, char *);
  89   char * decimal128ToEngString(const decimal128 *, char *);
  90
  91   /* decNumber conversions                                            */
  92   decimal128 * decimal128FromNumber(decimal128 *, const decNumber *,
  93                                     decContext *);
  94   decNumber * decimal128ToNumber(const decimal128 *, decNumber *);
  95
  96   /* Format-dependent utilities                                       */
  97   uint32_t    decimal128IsCanonical(const decimal128 *);
  98   decimal128 * decimal128Canonical(decimal128 *, const decimal128 *);
  99
 100   #ifdef __cplusplus
 101   }
 102   #endif
 103
 104 #endif