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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
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