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/****************************************************************

 *

 * The author of this software is David M. Gay.

 *

 * Copyright (c) 1991 by AT&T.

 *

 * Permission to use, copy, modify, and distribute this software for any

 * purpose without fee is hereby granted, provided that this entire notice

 * is included in all copies of any software which is or includes a copy

 * or modification of this software and in all copies of the supporting

 * documentation for such software.

 *

 * THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR IMPLIED

 * WARRANTY.  IN PARTICULAR, NEITHER THE AUTHOR NOR AT&T MAKES ANY

 * REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE MERCHANTABILITY

 * OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR PURPOSE.

 *

 ***************************************************************/

/* Please send bug reports to

        David M. Gay

        AT&T Bell Laboratories, Room 2C-463

        600 Mountain Avenue

        Murray Hill, NJ 07974-2070

        U.S.A.

        dmg@research.att.com or research!dmg

 */

/* This header file is a modification of mprec.h that only contains floating

   point union code. */

#include <ieeefp.h>

#include <math.h>

#include <float.h>

#include <errno.h>

#include <sys/config.h>

#ifdef __IEEE_LITTLE_ENDIAN

#define IEEE_8087

#endif

#ifdef __IEEE_BIG_ENDIAN

#define IEEE_MC68k

#endif

#ifdef __Z8000__

#define Just_16

#endif

#ifdef Unsigned_Shifts

#define Sign_Extend(a,b) if (b < 0) a |= (__uint32_t)0xffff0000;

#else

#define Sign_Extend(a,b) /*no-op*/

#endif

#if defined(IEEE_8087) + defined(IEEE_MC68k) + defined(VAX) + defined(IBM) != 1

Exactly one of IEEE_8087, IEEE_MC68k, VAX, or IBM should be defined.

#endif

#ifdef WANT_IO_LONG_DBL

/* If we are going to examine or modify specific bits in a long double using

   the lword0 or lwordx macros, then we must wrap the long double inside

   a union.  This is necessary to avoid undefined behavior according to

   the ANSI C spec.  */

#ifdef IEEE_8087

#if LDBL_MANT_DIG == 24

struct ldieee

{

  unsigned manh:23;

  unsigned exp:8;

  unsigned sign:1;

};

#elif LDBL_MANT_DIG == 53

struct ldieee

{

  unsigned manl:20;

  unsigned manh:32;

  unsigned exp:11;

  unsigned sign:1;

};

#elif LDBL_MANT_DIG == 64

struct ldieee

{

  unsigned manl:32;

  unsigned manh:32;

  unsigned exp:15;

  unsigned sign:1;

};

#elif LDBL_MANT_DIG > 64

struct ldieee

{

  unsigned manl3:16;

  unsigned manl2:32;

  unsigned manl:32;

  unsigned manh:32;

  unsigned exp:15;

  unsigned sign:1;

};

#endif /* LDBL_MANT_DIG */

#else  /* !IEEE_8087 */

#if LDBL_MANT_DIG == 24

struct ldieee

{

  unsigned sign:1;

  unsigned exp:8;

  unsigned manh:23;

};

#elif LDBL_MANT_DIG == 53

struct ldieee

{

  unsigned sign:1;

  unsigned exp:11;

  unsigned manh:32;

  unsigned manl:20;

};

#elif LDBL_MANT_DIG == 64

struct ldieee

{

  unsigned sign:1;

  unsigned exp:15;

  unsigned manh:32;

  unsigned manl:32;

};

#elif LDBL_MANT_DIG > 64

struct ldieee

{

  unsigned sign:1;

  unsigned exp:15;

  unsigned manh:32;

  unsigned manl:32;

  unsigned manl2:32;

  unsigned manl3;16;

};

#endif /* LDBL_MANT_DIG */

#endif /* !IEEE_8087 */

#endif /* WANT_IO_LONG_DBL */

/* If we are going to examine or modify specific bits in a double using

   the word0 and/or word1 macros, then we must wrap the double inside

   a union.  This is necessary to avoid undefined behavior according to

   the ANSI C spec.  */

union double_union

{

  double d;

  __uint32_t i[2];

};

#ifdef IEEE_8087

#define word0(x) (x.i[1])

#define word1(x) (x.i[0])

#else

#define word0(x) (x.i[0])

#define word1(x) (x.i[1])

#endif

/* #define P DBL_MANT_DIG */

/* Ten_pmax = floor(P*log(2)/log(5)) */

/* Bletch = (highest power of 2 < DBL_MAX_10_EXP) / 16 */

/* Quick_max = floor((P-1)*log(FLT_RADIX)/log(10) - 1) */

/* Int_max = floor(P*log(FLT_RADIX)/log(10) - 1) */

#if defined(IEEE_8087) + defined(IEEE_MC68k)

#if defined (_DOUBLE_IS_32BITS) 

#define Exp_shift   23

#define Exp_shift1  23

#define Exp_msk1    ((__uint32_t)0x00800000L)

#define Exp_msk11   ((__uint32_t)0x00800000L)

#define Exp_mask    ((__uint32_t)0x7f800000L)

#define P           24

#define Bias        127

#if 0

#define IEEE_Arith  /* it is, but the code doesn't handle IEEE singles yet */

#endif

#define Emin        (-126)

#define Exp_1       ((__uint32_t)0x3f800000L)

#define Exp_11      ((__uint32_t)0x3f800000L)

#define Ebits       8

#define Frac_mask   ((__uint32_t)0x007fffffL)

#define Frac_mask1  ((__uint32_t)0x007fffffL)

#define Ten_pmax    10

#define Sign_bit    ((__uint32_t)0x80000000L)

#define Ten_pmax    10

#define Bletch      2

#define Bndry_mask  ((__uint32_t)0x007fffffL)

#define Bndry_mask1 ((__uint32_t)0x007fffffL)

#define LSB 1

#define Sign_bit    ((__uint32_t)0x80000000L)

#define Log2P       1

#define Tiny0       0

#define Tiny1       1

#define Quick_max   5

#define Int_max     6

#define Infinite(x) (word0(x) == ((__uint32_t)0x7f800000L))

#undef word0

#undef word1

#define word0(x) (x.i[0])

#define word1(x) 0

#else

#define Exp_shift  20

#define Exp_shift1 20

#define Exp_msk1    ((__uint32_t)0x100000L)

#define Exp_msk11   ((__uint32_t)0x100000L)

#define Exp_mask  ((__uint32_t)0x7ff00000L)

#define P 53

#define Bias 1023

#define IEEE_Arith

#define Emin (-1022)

#define Exp_1  ((__uint32_t)0x3ff00000L)

#define Exp_11 ((__uint32_t)0x3ff00000L)

#define Ebits 11

#define Frac_mask  ((__uint32_t)0xfffffL)

#define Frac_mask1 ((__uint32_t)0xfffffL)

#define Ten_pmax 22

#define Bletch 0x10

#define Bndry_mask  ((__uint32_t)0xfffffL)

#define Bndry_mask1 ((__uint32_t)0xfffffL)

#define LSB 1

#define Sign_bit ((__uint32_t)0x80000000L)

#define Log2P 1

#define Tiny0 0

#define Tiny1 1

#define Quick_max 14

#define Int_max 14

#define Infinite(x) (word0(x) == ((__uint32_t)0x7ff00000L)) /* sufficient test for here */

#endif

#else

#undef  Sudden_Underflow

#define Sudden_Underflow

#ifdef IBM

#define Exp_shift  24

#define Exp_shift1 24

#define Exp_msk1   ((__uint32_t)0x1000000L)

#define Exp_msk11  ((__uint32_t)0x1000000L)

#define Exp_mask  ((__uint32_t)0x7f000000L)

#define P 14

#define Bias 65

#define Exp_1  ((__uint32_t)0x41000000L)

#define Exp_11 ((__uint32_t)0x41000000L)

#define Ebits 8 /* exponent has 7 bits, but 8 is the right value in b2d */

#define Frac_mask  ((__uint32_t)0xffffffL)

#define Frac_mask1 ((__uint32_t)0xffffffL)

#define Bletch 4

#define Ten_pmax 22

#define Bndry_mask  ((__uint32_t)0xefffffL)

#define Bndry_mask1 ((__uint32_t)0xffffffL)

#define LSB 1

#define Sign_bit ((__uint32_t)0x80000000L)

#define Log2P 4

#define Tiny0 ((__uint32_t)0x100000L)

#define Tiny1 0

#define Quick_max 14

#define Int_max 15

#else /* VAX */

#define Exp_shift  23

#define Exp_shift1 7

#define Exp_msk1    0x80

#define Exp_msk11   ((__uint32_t)0x800000L)

#define Exp_mask  ((__uint32_t)0x7f80L)

#define P 56

#define Bias 129

#define Exp_1  ((__uint32_t)0x40800000L)

#define Exp_11 ((__uint32_t)0x4080L)

#define Ebits 8

#define Frac_mask  ((__uint32_t)0x7fffffL)

#define Frac_mask1 ((__uint32_t)0xffff007fL)

#define Ten_pmax 24

#define Bletch 2

#define Bndry_mask  ((__uint32_t)0xffff007fL)

#define Bndry_mask1 ((__uint32_t)0xffff007fL)

#define LSB ((__uint32_t)0x10000L)

#define Sign_bit ((__uint32_t)0x8000L)

#define Log2P 1

#define Tiny0 0x80

#define Tiny1 0

#define Quick_max 15

#define Int_max 15

#endif

#endif