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/* Decimal 32-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, 51 Franklin Street, Fifth Floor, Boston, MA
   02110-1301, USA.  */

#if !defined(DECIMAL32)
#define DECIMAL32
#define DEC32NAME     "decimal32"	/* Short name */
#define DEC32FULLNAME "Decimal 32-bit Number"	/* Verbose name */
#define DEC32AUTHOR   "Mike Cowlishaw"	/* Who to blame */

  /* parameters for decimal32s */
#define DECIMAL32_Bytes  4	/* length */
#define DECIMAL32_Pmax   7	/* maximum precision (digits) */
#define DECIMAL32_Emax   96	/* maximum adjusted exponent */
#define DECIMAL32_Emin  -95	/* minimum adjusted exponent */
#define DECIMAL32_Bias   101	/* bias for the exponent */
#define DECIMAL32_String 15	/* maximum string length, +1 */
  /* highest biased exponent (Elimit-1) */
#define DECIMAL32_Ehigh  (DECIMAL32_Emax+DECIMAL32_Bias-DECIMAL32_Pmax+1)

#ifndef DECNUMDIGITS
#define DECNUMDIGITS DECIMAL32_Pmax	/* size if not already defined */
#endif
#ifndef DECNUMBER
#include "decNumber.h"		/* context and number library */
#endif

  /* Decimal 32-bit type, accessible by bytes */
typedef struct
{
  uint8_t bytes[DECIMAL32_Bytes];	/* decimal32: 1, 5, 6, 20 bits */
} decimal32;

  /* 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 decimal32 fields.  These assume the argument
     is a reference (pointer) to the decimal32 structure */
  /* Get sign */
#define decimal32Sign(d)       ((unsigned)(d)->bytes[0]>>7)

  /* Get combination field */
#define decimal32Comb(d)       (((d)->bytes[0] & 0x7c)>>2)

  /* Get exponent continuation [does not remove bias] */
#define decimal32ExpCon(d)     ((((d)->bytes[0] & 0x03)<<4)         \
                               | ((unsigned)(d)->bytes[1]>>4))

  /* Set sign [this assumes sign previously 0] */
#define decimal32SetSign(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 decimal32SetExpCon(d, e) {                                  \
    (d)->bytes[0]|=(uint8_t)((e)>>4);                                 \
    (d)->bytes[1]|=(uint8_t)(((e)&0x0F)<<4);}

  /* ------------------------------------------------------------------ */
  /* Routines                                                           */
  /* ------------------------------------------------------------------ */

#ifdef IN_LIBGCC2
#define decimal32FromString __decimal32FromString
#define decimal32ToString __decimal32ToString
#define decimal32ToEngString __decimal32ToEngString
#define decimal32FromNumber __decimal32FromNumber
#define decimal32ToNumber __decimal32ToNumber
#endif

/* String conversions.  */
decimal32 *decimal32FromString (decimal32 *, char *, decContext *);
char *decimal32ToString (decimal32 *, char *);
char *decimal32ToEngString (decimal32 *, char *);

/* decNumber conversions.  */
decimal32 *decimal32FromNumber (decimal32 *, decNumber *, decContext *);
decNumber *decimal32ToNumber (decimal32 *, decNumber *);

#endif