source: trunk/libs/newlib/src/newlib/libc/stdlib/ldtoa.c @ 444

 /* Extended precision arithmetic functions for long double I/O.
  * This program has been placed in the public domain.
  */

#include <_ansi.h>
#include <reent.h>
#include <string.h>
#include <stdlib.h>
#include "mprec.h"

/* These are the externally visible entries. */
/* linux name:  long double _IO_strtold (char *, char **); */
long double _strtold (char *, char **);
char *_ldtoa_r (struct _reent *, long double, int, int, int *, int *,
                char **);
int _ldcheck (long double *);
#if 0
void _IO_ldtostr (long double *, char *, int, int, char);
#endif

 /* Number of 16 bit words in external x type format */
#define NE 10

 /* Number of 16 bit words in internal format */
#define NI (NE+3)

 /* Array offset to exponent */
#define E 1

 /* Array offset to high guard word */
#define M 2

 /* Number of bits of precision */
#define NBITS ((NI-4)*16)

 /* Maximum number of decimal digits in ASCII conversion
  * = NBITS*log10(2)
  */
#define NDEC (NBITS*8/27)

 /* The exponent of 1.0 */
#define EXONE (0x3fff)

 /* Maximum exponent digits - base 10 */
#define MAX_EXP_DIGITS 5

/* Control structure for long double conversion including rounding precision values.
 * rndprc can be set to 80 (if NE=6), 64, 56, 53, or 24 bits.
 */
typedef struct
{
  int rlast;
  int rndprc;
  int rw;
  int re;
  int outexpon;
  unsigned short rmsk;
  unsigned short rmbit;
  unsigned short rebit;
  unsigned short rbit[NI];
  unsigned short equot[NI];
} LDPARMS;

static void esub (const short unsigned int *a, const short unsigned int *b,
                  short unsigned int *c, LDPARMS * ldp);
static void emul (const short unsigned int *a, const short unsigned int *b,
                  short unsigned int *c, LDPARMS * ldp);
static void ediv (const short unsigned int *a, const short unsigned int *b,
                  short unsigned int *c, LDPARMS * ldp);
static int ecmp (const short unsigned int *a, const short unsigned int *b);
static int enormlz (short unsigned int *x);
static int eshift (short unsigned int *x, int sc);
static void eshup1 (register short unsigned int *x);
static void eshup8 (register short unsigned int *x);
static void eshup6 (register short unsigned int *x);
static void eshdn1 (register short unsigned int *x);
static void eshdn8 (register short unsigned int *x);
static void eshdn6 (register short unsigned int *x);
static void eneg (short unsigned int *x);
static void emov (register const short unsigned int *a,
                  register short unsigned int *b);
static void eclear (register short unsigned int *x);
static void einfin (register short unsigned int *x, register LDPARMS * ldp);
static void efloor (short unsigned int *x, short unsigned int *y,
                    LDPARMS * ldp);
static void etoasc (short unsigned int *x, char *string, int ndigs,
                    int outformat, LDPARMS * ldp);

union uconv
{
  unsigned short pe;
  long double d;
};

#if LDBL_MANT_DIG == 24
static void e24toe (short unsigned int *pe, short unsigned int *y,
                    LDPARMS * ldp);
#elif LDBL_MANT_DIG == 53
static void e53toe (short unsigned int *pe, short unsigned int *y,
                    LDPARMS * ldp);
#elif LDBL_MANT_DIG == 64
static void e64toe (short unsigned int *pe, short unsigned int *y,
                    LDPARMS * ldp);
#else
static void e113toe (short unsigned int *pe, short unsigned int *y,
                     LDPARMS * ldp);
#endif

/*                                                      econst.c        */
/*  e type constants used by high precision check routines */

#if NE == 10
/* 0.0 */
static const unsigned short ezero[NE] = { 0x0000, 0x0000, 0x0000, 0x0000,
  0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000,
};

/* 1.0E0 */
static const unsigned short eone[NE] = { 0x0000, 0x0000, 0x0000, 0x0000,
  0x0000, 0x0000, 0x0000, 0x0000, 0x8000, 0x3fff,
};

#else

/* 0.0 */
static const unsigned short ezero[NE] = {
  0, 0000000, 0000000, 0000000, 0000000, 0000000,
};

/* 1.0E0 */
static const unsigned short eone[NE] = {
  0, 0000000, 0000000, 0000000, 0100000, 0x3fff,
};

#endif

/* Debugging routine for displaying errors */
#ifdef DEBUG
/* Notice: the order of appearance of the following
 * messages is bound to the error codes defined
 * in mconf.h.
 */
static const char *const ermsg[7] = {
  "unknown",                    /* error code 0 */
  "domain",                     /* error code 1 */
  "singularity",                /* et seq.      */
  "overflow",
  "underflow",
  "total loss of precision",
  "partial loss of precision"
};

#define mtherr(name, code) printf( "\n%s %s error\n", name, ermsg[code] );
#else
#define mtherr(name, code)
#endif

/*                                                      ieee.c
 *
 *    Extended precision IEEE binary floating point arithmetic routines
 *
 * Numbers are stored in C language as arrays of 16-bit unsigned
 * short integers.  The arguments of the routines are pointers to
 * the arrays.
 *
 *
 * External e type data structure, simulates Intel 8087 chip
 * temporary real format but possibly with a larger significand:
 *
 *      NE-1 significand words  (least significant word first,
 *                               most significant bit is normally set)
 *      exponent                (value = EXONE for 1.0,
 *                              top bit is the sign)
 *
 *
 * Internal data structure of a number (a "word" is 16 bits):
 *
 * ei[0]        sign word       (0 for positive, 0xffff for negative)
 * ei[1]        biased exponent (value = EXONE for the number 1.0)
 * ei[2]        high guard word (always zero after normalization)
 * ei[3]
 * to ei[NI-2]  significand     (NI-4 significand words,
 *                               most significant word first,
 *                               most significant bit is set)
 * ei[NI-1]     low guard word  (0x8000 bit is rounding place)
 *
 *
 *
 *              Routines for external format numbers
 *
 *      asctoe( string, e )     ASCII string to extended double e type
 *      asctoe64( string, &d )  ASCII string to long double
 *      asctoe53( string, &d )  ASCII string to double
 *      asctoe24( string, &f )  ASCII string to single
 *      asctoeg( string, e, prec, ldp ) ASCII string to specified precision
 *      e24toe( &f, e, ldp )    IEEE single precision to e type
 *      e53toe( &d, e, ldp )    IEEE double precision to e type
 *      e64toe( &d, e, ldp )    IEEE long double precision to e type
 *      e113toe( &d, e, ldp )   IEEE long double precision to e type
 *      eabs(e)                 absolute value
 *      eadd( a, b, c )         c = b + a
 *      eclear(e)               e = 0
 *      ecmp (a, b)             Returns 1 if a > b, 0 if a == b,
 *                              -1 if a < b, -2 if either a or b is a NaN.
 *      ediv( a, b, c, ldp )    c = b / a
 *      efloor( a, b, ldp )     truncate to integer, toward -infinity
 *      efrexp( a, exp, s )     extract exponent and significand
 *      eifrac( e, &l, frac )   e to long integer and e type fraction
 *      euifrac( e, &l, frac )  e to unsigned long integer and e type fraction
 *      einfin( e, ldp )        set e to infinity, leaving its sign alone
 *      eldexp( a, n, b )       multiply by 2**n
 *      emov( a, b )            b = a
 *      emul( a, b, c, ldp )    c = b * a
 *      eneg(e)                 e = -e
 *      eround( a, b )          b = nearest integer value to a
 *      esub( a, b, c, ldp )    c = b - a
 *      e24toasc( &f, str, n )  single to ASCII string, n digits after decimal
 *      e53toasc( &d, str, n )  double to ASCII string, n digits after decimal
 *      e64toasc( &d, str, n )  long double to ASCII string
 *      etoasc(e,str,n,fmt,ldp)e to ASCII string, n digits after decimal
 *      etoe24( e, &f )         convert e type to IEEE single precision
 *      etoe53( e, &d )         convert e type to IEEE double precision
 *      etoe64( e, &d )         convert e type to IEEE long double precision
 *      ltoe( &l, e )           long (32 bit) integer to e type
 *      ultoe( &l, e )          unsigned long (32 bit) integer to e type
 *      eisneg( e )             1 if sign bit of e != 0, else 0
 *      eisinf( e )             1 if e has maximum exponent (non-IEEE)
 *                              or is infinite (IEEE)
 *      eisnan( e )             1 if e is a NaN
 *      esqrt( a, b )           b = square root of a
 *
 *
 *              Routines for internal format numbers
 *
 *      eaddm( ai, bi )         add significands, bi = bi + ai
 *      ecleaz(ei)              ei = 0
 *      ecleazs(ei)             set ei = 0 but leave its sign alone
 *      ecmpm( ai, bi )         compare significands, return 1, 0, or -1
 *      edivm( ai, bi, ldp )    divide  significands, bi = bi / ai
 *      emdnorm(ai,l,s,exp,ldp) normalize and round off
 *      emovi( a, ai )          convert external a to internal ai
 *      emovo( ai, a, ldp )     convert internal ai to external a
 *      emovz( ai, bi )         bi = ai, low guard word of bi = 0
 *      emulm( ai, bi, ldp )    multiply significands, bi = bi * ai
 *      enormlz(ei)             left-justify the significand
 *      eshdn1( ai )            shift significand and guards down 1 bit
 *      eshdn8( ai )            shift down 8 bits
 *      eshdn6( ai )            shift down 16 bits
 *      eshift( ai, n )         shift ai n bits up (or down if n < 0)
 *      eshup1( ai )            shift significand and guards up 1 bit
 *      eshup8( ai )            shift up 8 bits
 *      eshup6( ai )            shift up 16 bits
 *      esubm( ai, bi )         subtract significands, bi = bi - ai
 *
 *
 * The result is always normalized and rounded to NI-4 word precision
 * after each arithmetic operation.
 *
 * Exception flags are NOT fully supported.
 *
 * Define USE_INFINITY in mconf.h for support of infinity; otherwise a
 * saturation arithmetic is implemented.
 *
 * Define NANS for support of Not-a-Number items; otherwise the
 * arithmetic will never produce a NaN output, and might be confused
 * by a NaN input.
 * If NaN's are supported, the output of ecmp(a,b) is -2 if
 * either a or b is a NaN. This means asking if(ecmp(a,b) < 0)
 * may not be legitimate. Use if(ecmp(a,b) == -1) for less-than
 * if in doubt.
 * Signaling NaN's are NOT supported; they are treated the same
 * as quiet NaN's.
 *
 * Denormals are always supported here where appropriate (e.g., not
 * for conversion to DEC numbers).
 */

/*
 * Revision history:
 *
 *  5 Jan 84    PDP-11 assembly language version
 *  6 Dec 86    C language version
 * 30 Aug 88    100 digit version, improved rounding
 * 15 May 92    80-bit long double support
 * 22 Nov 00    Revised to fit into newlib by Jeff Johnston <jjohnstn@redhat.com>
 *
 * Author:  S. L. Moshier.
 *
 * Copyright (c) 1984,2000 S.L. Moshier
 *
 * 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,  THE AUTHOR MAKES NO REPRESENTATION
 * OR WARRANTY OF ANY KIND CONCERNING THE MERCHANTABILITY OF THIS
 * SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR PURPOSE.
 *
 */

#include <stdio.h>
/* #include "\usr\include\stdio.h" */
/*#include "ehead.h"*/
/*#include "mconf.h"*/
/*                                                      mconf.h
 *
 *      Common include file for math routines
 *
 *
 *
 * SYNOPSIS:
 *
 * #include "mconf.h"
 *
 *
 *
 * DESCRIPTION:
 *
 * This file contains definitions for error codes that are
 * passed to the common error handling routine mtherr()
 * (which see).
 *
 * The file also includes a conditional assembly definition
 * for the type of computer arithmetic (IEEE, DEC, Motorola
 * IEEE, or UNKnown).
 *
 * For Digital Equipment PDP-11 and VAX computers, certain
 * IBM systems, and others that use numbers with a 56-bit
 * significand, the symbol DEC should be defined.  In this
 * mode, most floating point constants are given as arrays
 * of octal integers to eliminate decimal to binary conversion
 * errors that might be introduced by the compiler.
 *
 * For computers, such as IBM PC, that follow the IEEE 
 * Standard for Binary Floating Point Arithmetic (ANSI/IEEE
 * Std 754-1985), the symbol IBMPC should be defined.  These
 * numbers have 53-bit significands.  In this mode, constants
 * are provided as arrays of hexadecimal 16 bit integers.
 *
 * To accommodate other types of computer arithmetic, all
 * constants are also provided in a normal decimal radix
 * which one can hope are correctly converted to a suitable
 * format by the available C language compiler.  To invoke
 * this mode, the symbol UNK is defined.
 *
 * An important difference among these modes is a predefined
 * set of machine arithmetic constants for each.  The numbers
 * MACHEP (the machine roundoff error), MAXNUM (largest number
 * represented), and several other parameters are preset by
 * the configuration symbol.  Check the file const.c to
 * ensure that these values are correct for your computer.
 *
 * For ANSI C compatibility, define ANSIC equal to 1.  Currently
 * this affects only the atan2() function and others that use it.
 */

/* Constant definitions for math error conditions
 */

#define DOMAIN          1       /* argument domain error */
#define SING            2       /* argument singularity */
#define OVERFLOW        3       /* overflow range error */
#define UNDERFLOW       4       /* underflow range error */
#define TLOSS           5       /* total loss of precision */
#define PLOSS           6       /* partial loss of precision */

#define EDOM            33
#define ERANGE          34

typedef struct
{
  double r;
  double i;
} cmplx;

/* Type of computer arithmetic */

#ifndef DEC
#ifdef __IEEE_LITTLE_ENDIAN
#define IBMPC 1
#else /* !__IEEE_LITTLE_ENDIAN */
#define MIEEE 1
#endif /* !__IEEE_LITTLE_ENDIAN */
#endif /* !DEC */

/* Define 1 for ANSI C atan2() function
 * See atan.c and clog.c.
 */
#define ANSIC 1

/*define VOLATILE volatile*/
#define VOLATILE

#define NANS
#define USE_INFINITY

/* NaN's require infinity support. */
#ifdef NANS
#ifndef INFINITY
#define USE_INFINITY
#endif
#endif

/* This handles 64-bit long ints. */
#define LONGBITS (8 * sizeof(long))


static void eaddm (short unsigned int *x, short unsigned int *y);
static void esubm (short unsigned int *x, short unsigned int *y);
static void emdnorm (short unsigned int *s, int lost, int subflg,
                     long int exp, int rcntrl, LDPARMS * ldp);
static int asctoeg (char *ss, short unsigned int *y, int oprec,
                    LDPARMS * ldp);
static void enan (short unsigned int *nan, int size);
#if LDBL_MANT_DIG == 24
static void toe24 (short unsigned int *x, short unsigned int *y);
#elif LDBL_MANT_DIG == 53
static void toe53 (short unsigned int *x, short unsigned int *y);
#elif LDBL_MANT_DIG == 64
static void toe64 (short unsigned int *a, short unsigned int *b);
#else
static void toe113 (short unsigned int *a, short unsigned int *b);
#endif
static void eiremain (short unsigned int *den, short unsigned int *num,
                      LDPARMS * ldp);
static int ecmpm (register short unsigned int *a,
                  register short unsigned int *b);
static int edivm (short unsigned int *den, short unsigned int *num,
                  LDPARMS * ldp);
static int emulm (short unsigned int *a, short unsigned int *b,
                  LDPARMS * ldp);
static int eisneg (const short unsigned int *x);
static int eisinf (const short unsigned int *x);
static void emovi (const short unsigned int *a, short unsigned int *b);
static void emovo (short unsigned int *a, short unsigned int *b,
                   LDPARMS * ldp);
static void emovz (register short unsigned int *a,
                   register short unsigned int *b);
static void ecleaz (register short unsigned int *xi);
static void eadd1 (const short unsigned int *a, const short unsigned int *b,
                   short unsigned int *c, int subflg, LDPARMS * ldp);
static int eisnan (const short unsigned int *x);
static int eiisnan (short unsigned int *x);

#ifdef DEC
static void etodec (), todec (), dectoe ();
#endif

/*
; Clear out entire external format number.
;
; unsigned short x[];
; eclear( x );
*/

static void
eclear (register short unsigned int *x)
{
  register int i;

  for (i = 0; i < NE; i++)
    *x++ = 0;
}



/* Move external format number from a to b.
 *
 * emov( a, b );
 */

static void
emov (register const short unsigned int *a, register short unsigned int *b)
{
  register int i;

  for (i = 0; i < NE; i++)
    *b++ = *a++;
}


/*
;       Negate external format number
;
;       unsigned short x[NE];
;       eneg( x );
*/

static void
eneg (short unsigned int *x)
{

#ifdef NANS
  if (eisnan (x))
    return;
#endif
  x[NE - 1] ^= 0x8000;          /* Toggle the sign bit */
}



/* Return 1 if external format number is negative,
 * else return zero.
 */
static int
eisneg (const short unsigned int *x)
{

#ifdef NANS
  if (eisnan (x))
    return (0);
#endif
  if (x[NE - 1] & 0x8000)
    return (1);
  else
    return (0);
}


/* Return 1 if external format number has maximum possible exponent,
 * else return zero.
 */
static int
eisinf (const short unsigned int *x)
{

  if ((x[NE - 1] & 0x7fff) == 0x7fff)
    {
#ifdef NANS
      if (eisnan (x))
        return (0);
#endif
      return (1);
    }
  else
    return (0);
}

/* Check if e-type number is not a number.
 */
static int
eisnan (const short unsigned int *x)
{

#ifdef NANS
  int i;
/* NaN has maximum exponent */
  if ((x[NE - 1] & 0x7fff) != 0x7fff)
    return (0);
/* ... and non-zero significand field. */
  for (i = 0; i < NE - 1; i++)
    {
      if (*x++ != 0)
        return (1);
    }
#endif
  return (0);
}

/*
; Fill entire number, including exponent and significand, with
; largest possible number.  These programs implement a saturation
; value that is an ordinary, legal number.  A special value
; "infinity" may also be implemented; this would require tests
; for that value and implementation of special rules for arithmetic
; operations involving inifinity.
*/

static void
einfin (register short unsigned int *x, register LDPARMS * ldp)
{
  register int i;

#ifdef USE_INFINITY
  for (i = 0; i < NE - 1; i++)
    *x++ = 0;
  *x |= 32767;
  ldp = ldp;
#else
  for (i = 0; i < NE - 1; i++)
    *x++ = 0xffff;
  *x |= 32766;
  if (ldp->rndprc < NBITS)
    {
      if (ldp->rndprc == 113)
        {
          *(x - 9) = 0;
          *(x - 8) = 0;
        }
      if (ldp->rndprc == 64)
        {
          *(x - 5) = 0;
        }
      if (ldp->rndprc == 53)
        {
          *(x - 4) = 0xf800;
        }
      else
        {
          *(x - 4) = 0;
          *(x - 3) = 0;
          *(x - 2) = 0xff00;
        }
    }
#endif
}

/* Move in external format number,
 * converting it to internal format.
 */
static void
emovi (const short unsigned int *a, short unsigned int *b)
{
  register const unsigned short *p;
  register unsigned short *q;
  int i;

  q = b;
  p = a + (NE - 1);             /* point to last word of external number */
/* get the sign bit */
  if (*p & 0x8000)
    *q++ = 0xffff;
  else
    *q++ = 0;
/* get the exponent */
  *q = *p--;
  *q++ &= 0x7fff;               /* delete the sign bit */
#ifdef USE_INFINITY
  if ((*(q - 1) & 0x7fff) == 0x7fff)
    {
#ifdef NANS
      if (eisnan (a))
        {
          *q++ = 0;
          for (i = 3; i < NI; i++)
            *q++ = *p--;
          return;
        }
#endif
      for (i = 2; i < NI; i++)
        *q++ = 0;
      return;
    }
#endif
/* clear high guard word */
  *q++ = 0;
/* move in the significand */
  for (i = 0; i < NE - 1; i++)
    *q++ = *p--;
/* clear low guard word */
  *q = 0;
}


/* Move internal format number out,
 * converting it to external format.
 */
static void
emovo (short unsigned int *a, short unsigned int *b, LDPARMS * ldp)
{
  register unsigned short *p, *q;
  unsigned short i;

  p = a;
  q = b + (NE - 1);             /* point to output exponent */
/* combine sign and exponent */
  i = *p++;
  if (i)
    *q-- = *p++ | 0x8000;
  else
    *q-- = *p++;
#ifdef USE_INFINITY
  if (*(p - 1) == 0x7fff)
    {
#ifdef NANS
      if (eiisnan (a))
        {
          enan (b, NBITS);
          return;
        }
#endif
      einfin (b, ldp);
      return;
    }
#endif
/* skip over guard word */
  ++p;
/* move the significand */
  for (i = 0; i < NE - 1; i++)
    *q-- = *p++;
}


/* Clear out internal format number.
 */

static void
ecleaz (register short unsigned int *xi)
{
  register int i;

  for (i = 0; i < NI; i++)
    *xi++ = 0;
}

/* same, but don't touch the sign. */

static void
ecleazs (register short unsigned int *xi)
{
  register int i;

  ++xi;
  for (i = 0; i < NI - 1; i++)
    *xi++ = 0;
}




/* Move internal format number from a to b.
 */
static void
emovz (register short unsigned int *a, register short unsigned int *b)
{
  register int i;

  for (i = 0; i < NI - 1; i++)
    *b++ = *a++;
/* clear low guard word */
  *b = 0;
}

/* Return nonzero if internal format number is a NaN.
 */

static int
eiisnan (short unsigned int *x)
{
  int i;

  if ((x[E] & 0x7fff) == 0x7fff)
    {
      for (i = M + 1; i < NI; i++)
        {
          if (x[i] != 0)
            return (1);
        }
    }
  return (0);
}

#if LDBL_MANT_DIG == 64

/* Return nonzero if internal format number is infinite. */
static int
eiisinf (unsigned short x[])
{

#ifdef NANS
  if (eiisnan (x))
    return (0);
#endif
  if ((x[E] & 0x7fff) == 0x7fff)
    return (1);
  return (0);
}
#endif /* LDBL_MANT_DIG == 64 */

/*
;       Compare significands of numbers in internal format.
;       Guard words are included in the comparison.
;
;       unsigned short a[NI], b[NI];
;       cmpm( a, b );
;
;       for the significands:
;       returns +1 if a > b
;                0 if a == b
;               -1 if a < b
*/
static int
ecmpm (register short unsigned int *a, register short unsigned int *b)
{
  int i;

  a += M;                       /* skip up to significand area */
  b += M;
  for (i = M; i < NI; i++)
    {
      if (*a++ != *b++)
        goto difrnt;
    }
  return (0);

difrnt:
  if (*(--a) > *(--b))
    return (1);
  else
    return (-1);
}


/*
;       Shift significand down by 1 bit
*/

static void
eshdn1 (register short unsigned int *x)
{
  register unsigned short bits;
  int i;

  x += M;                       /* point to significand area */

  bits = 0;
  for (i = M; i < NI; i++)
    {
      if (*x & 1)
        bits |= 1;
      *x >>= 1;
      if (bits & 2)
        *x |= 0x8000;
      bits <<= 1;
      ++x;
    }
}



/*
;       Shift significand up by 1 bit
*/

static void
eshup1 (register short unsigned int *x)
{
  register unsigned short bits;
  int i;

  x += NI - 1;
  bits = 0;

  for (i = M; i < NI; i++)
    {
      if (*x & 0x8000)
        bits |= 1;
      *x <<= 1;
      if (bits & 2)
        *x |= 1;
      bits <<= 1;
      --x;
    }
}



/*
;       Shift significand down by 8 bits
*/

static void
eshdn8 (register short unsigned int *x)
{
  register unsigned short newbyt, oldbyt;
  int i;

  x += M;
  oldbyt = 0;
  for (i = M; i < NI; i++)
    {
      newbyt = *x << 8;
      *x >>= 8;
      *x |= oldbyt;
      oldbyt = newbyt;
      ++x;
    }
}

/*
;       Shift significand up by 8 bits
*/

static void
eshup8 (register short unsigned int *x)
{
  int i;
  register unsigned short newbyt, oldbyt;

  x += NI - 1;
  oldbyt = 0;

  for (i = M; i < NI; i++)
    {
      newbyt = *x >> 8;
      *x <<= 8;
      *x |= oldbyt;
      oldbyt = newbyt;
      --x;
    }
}

/*
;       Shift significand up by 16 bits
*/

static void
eshup6 (register short unsigned int *x)
{
  int i;
  register unsigned short *p;

  p = x + M;
  x += M + 1;

  for (i = M; i < NI - 1; i++)
    *p++ = *x++;

  *p = 0;
}

/*
;       Shift significand down by 16 bits
*/

static void
eshdn6 (register short unsigned int *x)
{
  int i;
  register unsigned short *p;

  x += NI - 1;
  p = x + 1;

  for (i = M; i < NI - 1; i++)
    *(--p) = *(--x);

  *(--p) = 0;
}

/*
;       Add significands
;       x + y replaces y
*/

static void
eaddm (short unsigned int *x, short unsigned int *y)
{
  register unsigned long a;
  int i;
  unsigned int carry;

  x += NI - 1;
  y += NI - 1;
  carry = 0;
  for (i = M; i < NI; i++)
    {
      a = (unsigned long) (*x) + (unsigned long) (*y) + carry;
      if (a & 0x10000)
        carry = 1;
      else
        carry = 0;
      *y = (unsigned short) a;
      --x;
      --y;
    }
}

/*
;       Subtract significands
;       y - x replaces y
*/

static void
esubm (short unsigned int *x, short unsigned int *y)
{
  unsigned long a;
  int i;
  unsigned int carry;

  x += NI - 1;
  y += NI - 1;
  carry = 0;
  for (i = M; i < NI; i++)
    {
      a = (unsigned long) (*y) - (unsigned long) (*x) - carry;
      if (a & 0x10000)
        carry = 1;
      else
        carry = 0;
      *y = (unsigned short) a;
      --x;
      --y;
    }
}


/* Divide significands */


/* Multiply significand of e-type number b
by 16-bit quantity a, e-type result to c. */

static void
m16m (short unsigned int a, short unsigned int *b, short unsigned int *c)
{
  register unsigned short *pp;
  register unsigned long carry;
  unsigned short *ps;
  unsigned short p[NI];
  unsigned long aa, m;
  int i;

  aa = a;
  pp = &p[NI - 2];
  *pp++ = 0;
  *pp = 0;
  ps = &b[NI - 1];

  for (i = M + 1; i < NI; i++)
    {
      if (*ps == 0)
        {
          --ps;
          --pp;
          *(pp - 1) = 0;
        }
      else
        {
          m = (unsigned long) aa **ps--;
          carry = (m & 0xffff) + *pp;
          *pp-- = (unsigned short) carry;
          carry = (carry >> 16) + (m >> 16) + *pp;
          *pp = (unsigned short) carry;
          *(pp - 1) = carry >> 16;
        }
    }
  for (i = M; i < NI; i++)
    c[i] = p[i];
}


/* Divide significands. Neither the numerator nor the denominator
is permitted to have its high guard word nonzero.  */


static int
edivm (short unsigned int *den, short unsigned int *num, LDPARMS * ldp)
{
  int i;
  register unsigned short *p;
  unsigned long tnum;
  unsigned short j, tdenm, tquot;
  unsigned short tprod[NI + 1];
  unsigned short *equot = ldp->equot;

  p = &equot[0];
  *p++ = num[0];
  *p++ = num[1];

  for (i = M; i < NI; i++)
    {
      *p++ = 0;
    }
  eshdn1 (num);
  tdenm = den[M + 1];
  for (i = M; i < NI; i++)
    {
      /* Find trial quotient digit (the radix is 65536). */
      tnum = (((unsigned long) num[M]) << 16) + num[M + 1];

      /* Do not execute the divide instruction if it will overflow. */
      if ((tdenm * 0xffffUL) < tnum)
        tquot = 0xffff;
      else
        tquot = tnum / tdenm;

      /* Prove that the divide worked. */
/*
        tcheck = (unsigned long )tquot * tdenm;
        if( tnum - tcheck > tdenm )
                tquot = 0xffff;
*/
      /* Multiply denominator by trial quotient digit. */
      m16m (tquot, den, tprod);
      /* The quotient digit may have been overestimated. */
      if (ecmpm (tprod, num) > 0)
        {
          tquot -= 1;
          esubm (den, tprod);
          if (ecmpm (tprod, num) > 0)
            {
              tquot -= 1;
              esubm (den, tprod);
            }
        }
/*
        if( ecmpm( tprod, num ) > 0 )
                {
                eshow( "tprod", tprod );
                eshow( "num  ", num );
                printf( "tnum = %08lx, tden = %04x, tquot = %04x\n",
                         tnum, den[M+1], tquot );
                }
*/
      esubm (tprod, num);
/*
        if( ecmpm( num, den ) >= 0 )
                {
                eshow( "num  ", num );
                eshow( "den  ", den );
                printf( "tnum = %08lx, tden = %04x, tquot = %04x\n",
                         tnum, den[M+1], tquot );
                }
*/
      equot[i] = tquot;
      eshup6 (num);
    }
/* test for nonzero remainder after roundoff bit */
  p = &num[M];
  j = 0;
  for (i = M; i < NI; i++)
    {
      j |= *p++;
    }
  if (j)
    j = 1;

  for (i = 0; i < NI; i++)
    num[i] = equot[i];

  return ((int) j);
}



/* Multiply significands */
static int
emulm (short unsigned int *a, short unsigned int *b, LDPARMS * ldp)
{
  unsigned short *p, *q;
  unsigned short pprod[NI];
  unsigned short j;
  int i;
  unsigned short *equot = ldp->equot;

  equot[0] = b[0];
  equot[1] = b[1];
  for (i = M; i < NI; i++)
    equot[i] = 0;

  j = 0;
  p = &a[NI - 1];
  q = &equot[NI - 1];
  for (i = M + 1; i < NI; i++)
    {
      if (*p == 0)
        {
          --p;
        }
      else
        {
          m16m (*p--, b, pprod);
          eaddm (pprod, equot);
        }
      j |= *q;
      eshdn6 (equot);
    }

  for (i = 0; i < NI; i++)
    b[i] = equot[i];

/* return flag for lost nonzero bits */
  return ((int) j);
}


/*
static void eshow(str, x)
char *str;
unsigned short *x;
{
int i;

printf( "%s ", str );
for( i=0; i<NI; i++ )
        printf( "%04x ", *x++ );
printf( "\n" );
}
*/


/*
 * Normalize and round off.
 *
 * The internal format number to be rounded is "s".
 * Input "lost" indicates whether the number is exact.
 * This is the so-called sticky bit.
 *
 * Input "subflg" indicates whether the number was obtained
 * by a subtraction operation.  In that case if lost is nonzero
 * then the number is slightly smaller than indicated.
 *
 * Input "exp" is the biased exponent, which may be negative.
 * the exponent field of "s" is ignored but is replaced by
 * "exp" as adjusted by normalization and rounding.
 *
 * Input "rcntrl" is the rounding control.
 */


static void
emdnorm (short unsigned int *s, int lost, int subflg, long int exp,
         int rcntrl, LDPARMS * ldp)
{
  int i, j;
  unsigned short r;

/* Normalize */
  j = enormlz (s);

/* a blank significand could mean either zero or infinity. */
#ifndef USE_INFINITY
  if (j > NBITS)
    {
      ecleazs (s);
      return;
    }
#endif
  exp -= j;
#ifndef USE_INFINITY
  if (exp >= 32767L)
    goto overf;
#else
  if ((j > NBITS) && (exp < 32767L))
    {
      ecleazs (s);
      return;
    }
#endif
  if (exp < 0L)
    {
      if (exp > (long) (-NBITS - 1))
        {
          j = (int) exp;
          i = eshift (s, j);
          if (i)
            lost = 1;
        }
      else
        {
          ecleazs (s);
          return;
        }
    }
/* Round off, unless told not to by rcntrl. */
  if (rcntrl == 0)
    goto mdfin;
/* Set up rounding parameters if the control register changed. */
  if (ldp->rndprc != ldp->rlast)
    {
      ecleaz (ldp->rbit);
      switch (ldp->rndprc)
        {
        default:
        case NBITS:
          ldp->rw = NI - 1;     /* low guard word */
          ldp->rmsk = 0xffff;
          ldp->rmbit = 0x8000;
          ldp->rebit = 1;
          ldp->re = ldp->rw - 1;
          break;
        case 113:
          ldp->rw = 10;
          ldp->rmsk = 0x7fff;
          ldp->rmbit = 0x4000;
          ldp->rebit = 0x8000;
          ldp->re = ldp->rw;
          break;
        case 64:
          ldp->rw = 7;
          ldp->rmsk = 0xffff;
          ldp->rmbit = 0x8000;
          ldp->rebit = 1;
          ldp->re = ldp->rw - 1;
          break;
/* For DEC arithmetic */
        case 56:
          ldp->rw = 6;
          ldp->rmsk = 0xff;
          ldp->rmbit = 0x80;
          ldp->rebit = 0x100;
          ldp->re = ldp->rw;
          break;
        case 53:
          ldp->rw = 6;
          ldp->rmsk = 0x7ff;
          ldp->rmbit = 0x0400;
          ldp->rebit = 0x800;
          ldp->re = ldp->rw;
          break;
        case 24:
          ldp->rw = 4;
          ldp->rmsk = 0xff;
          ldp->rmbit = 0x80;
          ldp->rebit = 0x100;
          ldp->re = ldp->rw;
          break;
        }
      ldp->rbit[ldp->re] = ldp->rebit;
      ldp->rlast = ldp->rndprc;
    }

/* Shift down 1 temporarily if the data structure has an implied
 * most significant bit and the number is denormal.
 * For rndprc = 64 or NBITS, there is no implied bit.
 * But Intel long double denormals lose one bit of significance even so.
 */
#if IBMPC
  if ((exp <= 0) && (ldp->rndprc != NBITS))
#else
  if ((exp <= 0) && (ldp->rndprc != 64) && (ldp->rndprc != NBITS))
#endif
    {
      lost |= s[NI - 1] & 1;
      eshdn1 (s);
    }
/* Clear out all bits below the rounding bit,
 * remembering in r if any were nonzero.
 */
  r = s[ldp->rw] & ldp->rmsk;
  if (ldp->rndprc < NBITS)
    {
      i = ldp->rw + 1;
      while (i < NI)
        {
          if (s[i])
            r |= 1;
          s[i] = 0;
          ++i;
        }
    }
  s[ldp->rw] &= ~ldp->rmsk;
  if ((r & ldp->rmbit) != 0)
    {
      if (r == ldp->rmbit)
        {
          if (lost == 0)
            {                   /* round to even */
              if ((s[ldp->re] & ldp->rebit) == 0)
                goto mddone;
            }
          else
            {
              if (subflg != 0)
                goto mddone;
            }
        }
      eaddm (ldp->rbit, s);
    }
mddone:
#if IBMPC
  if ((exp <= 0) && (ldp->rndprc != NBITS))
#else
  if ((exp <= 0) && (ldp->rndprc != 64) && (ldp->rndprc != NBITS))
#endif
    {
      eshup1 (s);
    }
  if (s[2] != 0)
    {                           /* overflow on roundoff */
      eshdn1 (s);
      exp += 1;
    }
mdfin:
  s[NI - 1] = 0;
  if (exp >= 32767L)
    {
#ifndef USE_INFINITY
    overf:
#endif
#ifdef USE_INFINITY
      s[1] = 32767;
      for (i = 2; i < NI - 1; i++)
        s[i] = 0;
#else
      s[1] = 32766;
      s[2] = 0;
      for (i = M + 1; i < NI - 1; i++)
        s[i] = 0xffff;
      s[NI - 1] = 0;
      if ((ldp->rndprc < 64) || (ldp->rndprc == 113))
        {
          s[ldp->rw] &= ~ldp->rmsk;
          if (ldp->rndprc == 24)
            {
              s[5] = 0;
              s[6] = 0;
            }
        }
#endif
      return;
    }
  if (exp < 0)
    s[1] = 0;
  else
    s[1] = (unsigned short) exp;
}



/*
;       Subtract external format numbers.
;
;       unsigned short a[NE], b[NE], c[NE];
;       LDPARMS *ldp;
;       esub( a, b, c, ldp );    c = b - a
*/

static void
esub (const short unsigned int *a, const short unsigned int *b,
      short unsigned int *c, LDPARMS * ldp)
{

#ifdef NANS
  if (eisnan (a))
    {
      emov (a, c);
      return;
    }
  if (eisnan (b))
    {
      emov (b, c);
      return;
    }
/* Infinity minus infinity is a NaN.
 * Test for subtracting infinities of the same sign.
 */
  if (eisinf (a) && eisinf (b) && ((eisneg (a) ^ eisneg (b)) == 0))
    {
      mtherr ("esub", DOMAIN);
      enan (c, NBITS);
      return;
    }
#endif
  eadd1 (a, b, c, 1, ldp);
}



static void
eadd1 (const short unsigned int *a, const short unsigned int *b,
       short unsigned int *c, int subflg, LDPARMS * ldp)
{
  unsigned short ai[NI], bi[NI], ci[NI];
  int i, lost, j, k;
  long lt, lta, ltb;

#ifdef USE_INFINITY
  if (eisinf (a))
    {
      emov (a, c);
      if (subflg)
        eneg (c);
      return;
    }
  if (eisinf (b))
    {
      emov (b, c);
      return;
    }
#endif
  emovi (a, ai);
  emovi (b, bi);
  if (subflg)
    ai[0] = ~ai[0];

/* compare exponents */
  lta = ai[E];
  ltb = bi[E];
  lt = lta - ltb;
  if (lt > 0L)
    {                           /* put the larger number in bi */
      emovz (bi, ci);
      emovz (ai, bi);
      emovz (ci, ai);
      ltb = bi[E];
      lt = -lt;
    }
  lost = 0;
  if (lt != 0L)
    {
      if (lt < (long) (-NBITS - 1))
        goto done;              /* answer same as larger addend */
      k = (int) lt;
      lost = eshift (ai, k);    /* shift the smaller number down */
    }
  else
    {
/* exponents were the same, so must compare significands */
      i = ecmpm (ai, bi);
      if (i == 0)
        {                       /* the numbers are identical in magnitude */
          /* if different signs, result is zero */
          if (ai[0] != bi[0])
            {
              eclear (c);
              return;
            }
          /* if same sign, result is double */
          /* double denomalized tiny number */
          if ((bi[E] == 0) && ((bi[3] & 0x8000) == 0))
            {
              eshup1 (bi);
              goto done;
            }
          /* add 1 to exponent unless both are zero! */
          for (j = 1; j < NI - 1; j++)
            {
              if (bi[j] != 0)
                {
/* This could overflow, but let emovo take care of that. */
                  ltb += 1;
                  break;
                }
            }
          bi[E] = (unsigned short) ltb;
          goto done;
        }
      if (i > 0)
        {                       /* put the larger number in bi */
          emovz (bi, ci);
          emovz (ai, bi);
          emovz (ci, ai);
        }
    }
  if (ai[0] == bi[0])
    {
      eaddm (ai, bi);
      subflg = 0;
    }
  else
    {
      esubm (ai, bi);
      subflg = 1;
    }
  emdnorm (bi, lost, subflg, ltb, 64, ldp);

done:
  emovo (bi, c, ldp);
}



/*
;       Divide.
;
;       unsigned short a[NE], b[NE], c[NE];
;       LDPARMS *ldp;
;       ediv( a, b, c, ldp );   c = b / a
*/
static void
ediv (const short unsigned int *a, const short unsigned int *b,
      short unsigned int *c, LDPARMS * ldp)
{
  unsigned short ai[NI], bi[NI];
  int i;
  long lt, lta, ltb;

#ifdef NANS
/* Return any NaN input. */
  if (eisnan (a))
    {
      emov (a, c);
      return;
    }
  if (eisnan (b))
    {
      emov (b, c);
      return;
    }
/* Zero over zero, or infinity over infinity, is a NaN. */
  if (((ecmp (a, ezero) == 0) && (ecmp (b, ezero) == 0))
      || (eisinf (a) && eisinf (b)))
    {
      mtherr ("ediv", DOMAIN);
      enan (c, NBITS);
      return;
    }
#endif
/* Infinity over anything else is infinity. */
#ifdef USE_INFINITY
  if (eisinf (b))
    {
      if (eisneg (a) ^ eisneg (b))
        *(c + (NE - 1)) = 0x8000;
      else
        *(c + (NE - 1)) = 0;
      einfin (c, ldp);
      return;
    }
  if (eisinf (a))
    {
      eclear (c);
      return;
    }
#endif
  emovi (a, ai);
  emovi (b, bi);
  lta = ai[E];
  ltb = bi[E];
  if (bi[E] == 0)
    {                           /* See if numerator is zero. */
      for (i = 1; i < NI - 1; i++)
        {
          if (bi[i] != 0)
            {
              ltb -= enormlz (bi);
              goto dnzro1;
            }
        }
      eclear (c);
      return;
    }
dnzro1:

  if (ai[E] == 0)
    {                           /* possible divide by zero */
      for (i = 1; i < NI - 1; i++)
        {
          if (ai[i] != 0)
            {
              lta -= enormlz (ai);
              goto dnzro2;
            }
        }
      if (ai[0] == bi[0])
        *(c + (NE - 1)) = 0;
      else
        *(c + (NE - 1)) = 0x8000;
      einfin (c, ldp);
      mtherr ("ediv", SING);
      return;
    }
dnzro2:

  i = edivm (ai, bi, ldp);
/* calculate exponent */
  lt = ltb - lta + EXONE;
  emdnorm (bi, i, 0, lt, 64, ldp);
/* set the sign */
  if (ai[0] == bi[0])
    bi[0] = 0;
  else
    bi[0] = 0Xffff;
  emovo (bi, c, ldp);
}



/*
;       Multiply.
;
;       unsigned short a[NE], b[NE], c[NE];
;       LDPARMS *ldp
;       emul( a, b, c, ldp );   c = b * a
*/
static void
emul (const short unsigned int *a, const short unsigned int *b,
      short unsigned int *c, LDPARMS * ldp)
{
  unsigned short ai[NI], bi[NI];
  int i, j;
  long lt, lta, ltb;

#ifdef NANS
/* NaN times anything is the same NaN. */
  if (eisnan (a))
    {
      emov (a, c);
      return;
    }
  if (eisnan (b))
    {
      emov (b, c);
      return;
    }
/* Zero times infinity is a NaN. */
  if ((eisinf (a) && (ecmp (b, ezero) == 0))
      || (eisinf (b) && (ecmp (a, ezero) == 0)))
    {
      mtherr ("emul", DOMAIN);
      enan (c, NBITS);
      return;
    }
#endif
/* Infinity times anything else is infinity. */
#ifdef USE_INFINITY
  if (eisinf (a) || eisinf (b))
    {
      if (eisneg (a) ^ eisneg (b))
        *(c + (NE - 1)) = 0x8000;
      else
        *(c + (NE - 1)) = 0;
      einfin (c, ldp);
      return;
    }
#endif
  emovi (a, ai);
  emovi (b, bi);
  lta = ai[E];
  ltb = bi[E];
  if (ai[E] == 0)
    {
      for (i = 1; i < NI - 1; i++)
        {
          if (ai[i] != 0)
            {
              lta -= enormlz (ai);
              goto mnzer1;
            }
        }
      eclear (c);
      return;
    }
mnzer1:

  if (bi[E] == 0)
    {
      for (i = 1; i < NI - 1; i++)
        {
          if (bi[i] != 0)
            {
              ltb -= enormlz (bi);
              goto mnzer2;
            }
        }
      eclear (c);
      return;
    }
mnzer2:

/* Multiply significands */
  j = emulm (ai, bi, ldp);
/* calculate exponent */
  lt = lta + ltb - (EXONE - 1);
  emdnorm (bi, j, 0, lt, 64, ldp);
/* calculate sign of product */
  if (ai[0] == bi[0])
    bi[0] = 0;
  else
    bi[0] = 0xffff;
  emovo (bi, c, ldp);
}



#if LDBL_MANT_DIG > 64
static void
e113toe (short unsigned int *pe, short unsigned int *y, LDPARMS * ldp)
{
  register unsigned short r;
  unsigned short *e, *p;
  unsigned short yy[NI];
  int denorm, i;

  e = pe;
  denorm = 0;
  ecleaz (yy);
#ifdef IBMPC
  e += 7;
#endif
  r = *e;
  yy[0] = 0;
  if (r & 0x8000)
    yy[0] = 0xffff;
  r &= 0x7fff;
#ifdef USE_INFINITY
  if (r == 0x7fff)
    {
#ifdef NANS
#ifdef IBMPC
      for (i = 0; i < 7; i++)
        {
          if (pe[i] != 0)
            {
              enan (y, NBITS);
              return;
            }
        }
#else /* !IBMPC */
      for (i = 1; i < 8; i++)
        {
          if (pe[i] != 0)
            {
              enan (y, NBITS);
              return;
            }
        }
#endif /* !IBMPC */
#endif /* NANS */
      eclear (y);
      einfin (y, ldp);
      if (*e & 0x8000)
        eneg (y);
      return;
    }
#endif /* INFINITY */
  yy[E] = r;
  p = &yy[M + 1];
#ifdef IBMPC
  for (i = 0; i < 7; i++)
    *p++ = *(--e);
#else /* IBMPC */
  ++e;
  for (i = 0; i < 7; i++)
    *p++ = *e++;
#endif /* IBMPC */
/* If denormal, remove the implied bit; else shift down 1. */
  if (r == 0)
    {
      yy[M] = 0;
    }
  else
    {
      yy[M] = 1;
      eshift (yy, -1);
    }
  emovo (yy, y, ldp);
}

/* move out internal format to ieee long double */
static void
toe113 (short unsigned int *a, short unsigned int *b)
{
  register unsigned short *p, *q;
  unsigned short i;

#ifdef NANS
  if (eiisnan (a))
    {
      enan (b, 113);
      return;
    }
#endif
  p = a;
#ifdef MIEEE
  q = b;
#else
  q = b + 7;                    /* point to output exponent */
#endif

/* If not denormal, delete the implied bit. */
  if (a[E] != 0)
    {
      eshup1 (a);
    }
/* combine sign and exponent */
  i = *p++;
#ifdef MIEEE
  if (i)
    *q++ = *p++ | 0x8000;
  else
    *q++ = *p++;
#else
  if (i)
    *q-- = *p++ | 0x8000;
  else
    *q-- = *p++;
#endif
/* skip over guard word */
  ++p;
/* move the significand */
#ifdef MIEEE
  for (i = 0; i < 7; i++)
    *q++ = *p++;
#else
  for (i = 0; i < 7; i++)
    *q-- = *p++;
#endif
}
#endif /* LDBL_MANT_DIG > 64 */


#if LDBL_MANT_DIG == 64
static void
e64toe (short unsigned int *pe, short unsigned int *y, LDPARMS * ldp)
{
  unsigned short yy[NI];
  unsigned short *p, *q, *e;
  int i;

  e = pe;
  p = yy;

  for (i = 0; i < NE - 5; i++)
    *p++ = 0;
#ifdef IBMPC
  for (i = 0; i < 5; i++)
    *p++ = *e++;
#endif
#ifdef DEC
  for (i = 0; i < 5; i++)
    *p++ = *e++;
#endif
#ifdef MIEEE
  p = &yy[0] + (NE - 1);
  *p-- = *e++;
  ++e;                          /* MIEEE skips over 2nd short */
  for (i = 0; i < 4; i++)
    *p-- = *e++;
#endif

#ifdef IBMPC
/* For Intel long double, shift denormal significand up 1
   -- but only if the top significand bit is zero.  */
  if ((yy[NE - 1] & 0x7fff) == 0 && (yy[NE - 2] & 0x8000) == 0)
    {
      unsigned short temp[NI + 1];
      emovi (yy, temp);
      eshup1 (temp);
      emovo (temp, y, ldp);
      return;
    }
#endif
#ifdef USE_INFINITY
/* Point to the exponent field.  */
  p = &yy[NE - 1];
  if ((*p & 0x7fff) == 0x7fff)
    {
#ifdef NANS
#ifdef IBMPC
      for (i = 0; i < 4; i++)
        {
          if ((i != 3 && pe[i] != 0)
              /* Check for Intel long double infinity pattern.  */
              || (i == 3 && pe[i] != 0x8000))
            {
              enan (y, NBITS);
              return;
            }
        }
#endif
#ifdef MIEEE
      for (i = 2; i <= 5; i++)
        {
          if (pe[i] != 0)
            {
              enan (y, NBITS);
              return;
            }
        }
#endif
#endif /* NANS */
      eclear (y);
      einfin (y, ldp);
      if (*p & 0x8000)
        eneg (y);
      return;
    }
#endif /* USE_INFINITY */
  p = yy;
  q = y;
  for (i = 0; i < NE; i++)
    *q++ = *p++;
}

/* move out internal format to ieee long double */
static void
toe64 (short unsigned int *a, short unsigned int *b)
{
  register unsigned short *p, *q;
  unsigned short i;

#ifdef NANS
  if (eiisnan (a))
    {
      enan (b, 64);
      return;
    }
#endif
#ifdef IBMPC
/* Shift Intel denormal significand down 1.  */
  if (a[E] == 0)
    eshdn1 (a);
#endif
  p = a;
#ifdef MIEEE
  q = b;
#else
  q = b + 4;                    /* point to output exponent */
/* NOTE: Intel data type is 96 bits wide, clear the last word here. */
  *(q + 1) = 0;
#endif

/* combine sign and exponent */
  i = *p++;
#ifdef MIEEE
  if (i)
    *q++ = *p++ | 0x8000;
  else
    *q++ = *p++;
  *q++ = 0;                     /* leave 2nd short blank */
#else
  if (i)
    *q-- = *p++ | 0x8000;
  else
    *q-- = *p++;
#endif
/* skip over guard word */
  ++p;
/* move the significand */
#ifdef MIEEE
  for (i = 0; i < 4; i++)
    *q++ = *p++;
#else
#ifdef USE_INFINITY
#ifdef IBMPC
  if (eiisinf (a))
    {
      /* Intel long double infinity.  */
      *q-- = 0x8000;
      *q-- = 0;
      *q-- = 0;
      *q = 0;
      return;
    }
#endif /* IBMPC */
#endif /* USE_INFINITY */
  for (i = 0; i < 4; i++)
    *q-- = *p++;
#endif
}

#endif /* LDBL_MANT_DIG == 64 */

#if LDBL_MANT_DIG == 53
/*
; Convert IEEE double precision to e type
;       double d;
;       unsigned short x[N+2];
;       e53toe( &d, x );
*/
static void
e53toe (short unsigned int *pe, short unsigned int *y, LDPARMS * ldp)
{
#ifdef DEC

  dectoe (pe, y);               /* see etodec.c */

#else

  register unsigned short r;
  register unsigned short *p, *e;
  unsigned short yy[NI];
  int denorm, k;

  e = pe;
  denorm = 0;                   /* flag if denormalized number */
  ecleaz (yy);
#ifdef IBMPC
  e += 3;
#endif
#ifdef DEC
  e += 3;
#endif
  r = *e;
  yy[0] = 0;
  if (r & 0x8000)
    yy[0] = 0xffff;
  yy[M] = (r & 0x0f) | 0x10;
  r &= ~0x800f;                 /* strip sign and 4 significand bits */
#ifdef USE_INFINITY
  if (r == 0x7ff0)
    {
#ifdef NANS
#ifdef IBMPC
      if (((pe[3] & 0xf) != 0) || (pe[2] != 0)
          || (pe[1] != 0) || (pe[0] != 0))
        {
          enan (y, NBITS);
          return;
        }
#else /* !IBMPC */
      if (((pe[0] & 0xf) != 0) || (pe[1] != 0)
          || (pe[2] != 0) || (pe[3] != 0))
        {
          enan (y, NBITS);
          return;
        }
#endif /* !IBMPC */
#endif /* NANS */
      eclear (y);
      einfin (y, ldp);
      if (yy[0])
        eneg (y);
      return;
    }
#endif
  r >>= 4;
/* If zero exponent, then the significand is denormalized.
 * So, take back the understood high significand bit. */
  if (r == 0)
    {
      denorm = 1;
      yy[M] &= ~0x10;
    }
  r += EXONE - 01777;
  yy[E] = r;
  p = &yy[M + 1];
#ifdef IBMPC
  *p++ = *(--e);
  *p++ = *(--e);
  *p++ = *(--e);
#else /* !IBMPC */
  ++e;
  *p++ = *e++;
  *p++ = *e++;
  *p++ = *e++;
#endif /* !IBMPC */
  (void) eshift (yy, -5);
  if (denorm)
    {                           /* if zero exponent, then normalize the significand */
      if ((k = enormlz (yy)) > NBITS)
        ecleazs (yy);
      else
        yy[E] -= (unsigned short) (k - 1);
    }
  emovo (yy, y, ldp);
#endif /* !DEC */
}

/*
; e type to IEEE double precision
;       double d;
;       unsigned short x[NE];
;       etoe53( x, &d );
*/

#ifdef DEC

static void
etoe53 (x, e)
     unsigned short *x, *e;
{
  etodec (x, e);                /* see etodec.c */
}

static void
toe53 (x, y)
     unsigned short *x, *y;
{
  todec (x, y);
}

#else

static void
toe53 (short unsigned int *x, short unsigned int *y)
{
  unsigned short i;
  unsigned short *p;


#ifdef NANS
  if (eiisnan (x))
    {
      enan (y, 53);
      return;
    }
#endif
  p = &x[0];
#ifdef IBMPC
  y += 3;
#endif
#ifdef DEC
  y += 3;
#endif
  *y = 0;                       /* output high order */
  if (*p++)
    *y = 0x8000;                /* output sign bit */

  i = *p++;
  if (i >= (unsigned int) 2047)
    {                           /* Saturate at largest number less than infinity. */
#ifdef USE_INFINITY
      *y |= 0x7ff0;
#ifdef IBMPC
      *(--y) = 0;
      *(--y) = 0;
      *(--y) = 0;
#else /* !IBMPC */
      ++y;
      *y++ = 0;
      *y++ = 0;
      *y++ = 0;
#endif /* IBMPC */
#else /* !USE_INFINITY */
      *y |= (unsigned short) 0x7fef;
#ifdef IBMPC
      *(--y) = 0xffff;
      *(--y) = 0xffff;
      *(--y) = 0xffff;
#else /* !IBMPC */
      ++y;
      *y++ = 0xffff;
      *y++ = 0xffff;
      *y++ = 0xffff;
#endif
#endif /* !USE_INFINITY */
      return;
    }
  if (i == 0)
    {
      (void) eshift (x, 4);
    }
  else
    {
      i <<= 4;
      (void) eshift (x, 5);
    }
  i |= *p++ & (unsigned short) 0x0f;    /* *p = xi[M] */
  *y |= (unsigned short) i;     /* high order output already has sign bit set */
#ifdef IBMPC
  *(--y) = *p++;
  *(--y) = *p++;
  *(--y) = *p;
#else /* !IBMPC */
  ++y;
  *y++ = *p++;
  *y++ = *p++;
  *y++ = *p++;
#endif /* !IBMPC */
}

#endif /* not DEC */
#endif /* LDBL_MANT_DIG == 53 */

#if LDBL_MANT_DIG == 24
/*
; Convert IEEE single precision to e type
;       float d;
;       unsigned short x[N+2];
;       dtox( &d, x );
*/
void
e24toe (short unsigned int *pe, short unsigned int *y, LDPARMS * ldp)
{
  register unsigned short r;
  register unsigned short *p, *e;
  unsigned short yy[NI];
  int denorm, k;

  e = pe;
  denorm = 0;                   /* flag if denormalized number */
  ecleaz (yy);
#ifdef IBMPC
  e += 1;
#endif
#ifdef DEC
  e += 1;
#endif
  r = *e;
  yy[0] = 0;
  if (r & 0x8000)
    yy[0] = 0xffff;
  yy[M] = (r & 0x7f) | 0200;
  r &= ~0x807f;                 /* strip sign and 7 significand bits */
#ifdef USE_INFINITY
  if (r == 0x7f80)
    {
#ifdef NANS
#ifdef MIEEE
      if (((pe[0] & 0x7f) != 0) || (pe[1] != 0))
        {
          enan (y, NBITS);
          return;
        }
#else /* !MIEEE */
      if (((pe[1] & 0x7f) != 0) || (pe[0] != 0))
        {
          enan (y, NBITS);
          return;
        }
#endif /* !MIEEE */
#endif /* NANS */
      eclear (y);
      einfin (y, ldp);
      if (yy[0])
        eneg (y);
      return;
    }
#endif
  r >>= 7;
/* If zero exponent, then the significand is denormalized.
 * So, take back the understood high significand bit. */
  if (r == 0)
    {
      denorm = 1;
      yy[M] &= ~0200;
    }
  r += EXONE - 0177;
  yy[E] = r;
  p = &yy[M + 1];
#ifdef IBMPC
  *p++ = *(--e);
#endif
#ifdef DEC
  *p++ = *(--e);
#endif
#ifdef MIEEE
  ++e;
  *p++ = *e++;
#endif
  (void) eshift (yy, -8);
  if (denorm)
    {                           /* if zero exponent, then normalize the significand */
      if ((k = enormlz (yy)) > NBITS)
        ecleazs (yy);
      else
        yy[E] -= (unsigned short) (k - 1);
    }
  emovo (yy, y, ldp);
}

static void
toe24 (short unsigned int *x, short unsigned int *y)
{
  unsigned short i;
  unsigned short *p;

#ifdef NANS
  if (eiisnan (x))
    {
      enan (y, 24);
      return;
    }
#endif
  p = &x[0];
#ifdef IBMPC
  y += 1;
#endif
#ifdef DEC
  y += 1;
#endif
  *y = 0;                       /* output high order */
  if (*p++)
    *y = 0x8000;                /* output sign bit */

  i = *p++;
  if (i >= 255)
    {                           /* Saturate at largest number less than infinity. */
#ifdef USE_INFINITY
      *y |= (unsigned short) 0x7f80;
#ifdef IBMPC
      *(--y) = 0;
#endif
#ifdef DEC
      *(--y) = 0;
#endif
#ifdef MIEEE
      ++y;
      *y = 0;
#endif
#else /* !USE_INFINITY */
      *y |= (unsigned short) 0x7f7f;
#ifdef IBMPC
      *(--y) = 0xffff;
#endif
#ifdef DEC
      *(--y) = 0xffff;
#endif
#ifdef MIEEE
      ++y;
      *y = 0xffff;
#endif
#endif /* !USE_INFINITY */
      return;
    }
  if (i == 0)
    {
      (void) eshift (x, 7);
    }
  else
    {
      i <<= 7;
      (void) eshift (x, 8);
    }
  i |= *p++ & (unsigned short) 0x7f;    /* *p = xi[M] */
  *y |= i;                      /* high order output already has sign bit set */
#ifdef IBMPC
  *(--y) = *p;
#endif
#ifdef DEC
  *(--y) = *p;
#endif
#ifdef MIEEE
  ++y;
  *y = *p;
#endif
}
#endif /* LDBL_MANT_DIG == 24 */

/* Compare two e type numbers.
 *
 * unsigned short a[NE], b[NE];
 * ecmp( a, b );
 *
 *  returns +1 if a > b
 *           0 if a == b
 *          -1 if a < b
 *          -2 if either a or b is a NaN.
 */
static int
ecmp (const short unsigned int *a, const short unsigned int *b)
{
  unsigned short ai[NI], bi[NI];
  register unsigned short *p, *q;
  register int i;
  int msign;

#ifdef NANS
  if (eisnan (a) || eisnan (b))
    return (-2);
#endif
  emovi (a, ai);
  p = ai;
  emovi (b, bi);
  q = bi;

  if (*p != *q)
    {                           /* the signs are different */
/* -0 equals + 0 */
      for (i = 1; i < NI - 1; i++)
        {
          if (ai[i] != 0)
            goto nzro;
          if (bi[i] != 0)
            goto nzro;
        }
      return (0);
    nzro:
      if (*p == 0)
        return (1);
      else
        return (-1);
    }
/* both are the same sign */
  if (*p == 0)
    msign = 1;
  else
    msign = -1;
  i = NI - 1;
  do
    {
      if (*p++ != *q++)
        {
          goto diff;
        }
    }
  while (--i > 0);

  return (0);                   /* equality */



diff:

  if (*(--p) > *(--q))
    return (msign);             /* p is bigger */
  else
    return (-msign);            /* p is littler */
}


/*
;       Shift significand
;
;       Shifts significand area up or down by the number of bits
;       given by the variable sc.
*/
static int
eshift (short unsigned int *x, int sc)
{
  unsigned short lost;
  unsigned short *p;

  if (sc == 0)
    return (0);

  lost = 0;
  p = x + NI - 1;

  if (sc < 0)
    {
      sc = -sc;
      while (sc >= 16)
        {
          lost |= *p;           /* remember lost bits */
          eshdn6 (x);
          sc -= 16;
        }

      while (sc >= 8)
        {
          lost |= *p & 0xff;
          eshdn8 (x);
          sc -= 8;
        }

      while (sc > 0)
        {
          lost |= *p & 1;
          eshdn1 (x);
          sc -= 1;
        }
    }
  else
    {
      while (sc >= 16)
        {
          eshup6 (x);
          sc -= 16;
        }

      while (sc >= 8)
        {
          eshup8 (x);
          sc -= 8;
        }

      while (sc > 0)
        {
          eshup1 (x);
          sc -= 1;
        }
    }
  if (lost)
    lost = 1;
  return ((int) lost);
}



/*
;       normalize
;
; Shift normalizes the significand area pointed to by argument
; shift count (up = positive) is returned.
*/
static int
enormlz (short unsigned int *x)
{
  register unsigned short *p;
  int sc;

  sc = 0;
  p = &x[M];
  if (*p != 0)
    goto normdn;
  ++p;
  if (*p & 0x8000)
    return (0);                 /* already normalized */
  while (*p == 0)
    {
      eshup6 (x);
      sc += 16;
/* With guard word, there are NBITS+16 bits available.
 * return true if all are zero.
 */
      if (sc > NBITS)
        return (sc);
    }
/* see if high byte is zero */
  while ((*p & 0xff00) == 0)
    {
      eshup8 (x);
      sc += 8;
    }
/* now shift 1 bit at a time */
  while ((*p & 0x8000) == 0)
    {
      eshup1 (x);
      sc += 1;
      if (sc > (NBITS + 16))
        {
          mtherr ("enormlz", UNDERFLOW);
          return (sc);
        }
    }
  return (sc);

/* Normalize by shifting down out of the high guard word
   of the significand */
normdn:

  if (*p & 0xff00)
    {
      eshdn8 (x);
      sc -= 8;
    }
  while (*p != 0)
    {
      eshdn1 (x);
      sc -= 1;

      if (sc < -NBITS)
        {
          mtherr ("enormlz", OVERFLOW);
          return (sc);
        }
    }
  return (sc);
}




/* Convert e type number to decimal format ASCII string.
 * The constants are for 64 bit precision.
 */

#define NTEN 12
#define MAXP 4096

#if NE == 10
static const unsigned short etens[NTEN + 1][NE] = {
  {0x6576, 0x4a92, 0x804a, 0x153f,
   0xc94c, 0x979a, 0x8a20, 0x5202, 0xc460, 0x7525,},    /* 10**4096 */
  {0x6a32, 0xce52, 0x329a, 0x28ce,
   0xa74d, 0x5de4, 0xc53d, 0x3b5d, 0x9e8b, 0x5a92,},    /* 10**2048 */
  {0x526c, 0x50ce, 0xf18b, 0x3d28,
   0x650d, 0x0c17, 0x8175, 0x7586, 0xc976, 0x4d48,},
  {0x9c66, 0x58f8, 0xbc50, 0x5c54,
   0xcc65, 0x91c6, 0xa60e, 0xa0ae, 0xe319, 0x46a3,},
  {0x851e, 0xeab7, 0x98fe, 0x901b,
   0xddbb, 0xde8d, 0x9df9, 0xebfb, 0xaa7e, 0x4351,},
  {0x0235, 0x0137, 0x36b1, 0x336c,
   0xc66f, 0x8cdf, 0x80e9, 0x47c9, 0x93ba, 0x41a8,},
  {0x50f8, 0x25fb, 0xc76b, 0x6b71,
   0x3cbf, 0xa6d5, 0xffcf, 0x1f49, 0xc278, 0x40d3,},
  {0x0000, 0x0000, 0x0000, 0x0000,
   0xf020, 0xb59d, 0x2b70, 0xada8, 0x9dc5, 0x4069,},
  {0x0000, 0x0000, 0x0000, 0x0000,
   0x0000, 0x0000, 0x0400, 0xc9bf, 0x8e1b, 0x4034,},
  {0x0000, 0x0000, 0x0000, 0x0000,
   0x0000, 0x0000, 0x0000, 0x2000, 0xbebc, 0x4019,},
  {0x0000, 0x0000, 0x0000, 0x0000,
   0x0000, 0x0000, 0x0000, 0x0000, 0x9c40, 0x400c,},
  {0x0000, 0x0000, 0x0000, 0x0000,
   0x0000, 0x0000, 0x0000, 0x0000, 0xc800, 0x4005,},
  {0x0000, 0x0000, 0x0000, 0x0000,
   0x0000, 0x0000, 0x0000, 0x0000, 0xa000, 0x4002,},    /* 10**1 */
};

static const unsigned short emtens[NTEN + 1][NE] = {
  {0x2030, 0xcffc, 0xa1c3, 0x8123,
   0x2de3, 0x9fde, 0xd2ce, 0x04c8, 0xa6dd, 0x0ad8,},    /* 10**-4096 */
  {0x8264, 0xd2cb, 0xf2ea, 0x12d4,
   0x4925, 0x2de4, 0x3436, 0x534f, 0xceae, 0x256b,},    /* 10**-2048 */
  {0xf53f, 0xf698, 0x6bd3, 0x0158,
   0x87a6, 0xc0bd, 0xda57, 0x82a5, 0xa2a6, 0x32b5,},
  {0xe731, 0x04d4, 0xe3f2, 0xd332,
   0x7132, 0xd21c, 0xdb23, 0xee32, 0x9049, 0x395a,},
  {0xa23e, 0x5308, 0xfefb, 0x1155,
   0xfa91, 0x1939, 0x637a, 0x4325, 0xc031, 0x3cac,},
  {0xe26d, 0xdbde, 0xd05d, 0xb3f6,
   0xac7c, 0xe4a0, 0x64bc, 0x467c, 0xddd0, 0x3e55,},
  {0x2a20, 0x6224, 0x47b3, 0x98d7,
   0x3f23, 0xe9a5, 0xa539, 0xea27, 0xa87f, 0x3f2a,},
  {0x0b5b, 0x4af2, 0xa581, 0x18ed,
   0x67de, 0x94ba, 0x4539, 0x1ead, 0xcfb1, 0x3f94,},
  {0xbf71, 0xa9b3, 0x7989, 0xbe68,
   0x4c2e, 0xe15b, 0xc44d, 0x94be, 0xe695, 0x3fc9,},
  {0x3d4d, 0x7c3d, 0x36ba, 0x0d2b,
   0xfdc2, 0xcefc, 0x8461, 0x7711, 0xabcc, 0x3fe4,},
  {0xc155, 0xa4a8, 0x404e, 0x6113,
   0xd3c3, 0x652b, 0xe219, 0x1758, 0xd1b7, 0x3ff1,},
  {0xd70a, 0x70a3, 0x0a3d, 0xa3d7,
   0x3d70, 0xd70a, 0x70a3, 0x0a3d, 0xa3d7, 0x3ff8,},
  {0xcccd, 0xcccc, 0xcccc, 0xcccc,
   0xcccc, 0xcccc, 0xcccc, 0xcccc, 0xcccc, 0x3ffb,},    /* 10**-1 */
};
#else
static const unsigned short etens[NTEN + 1][NE] = {
  {0xc94c, 0x979a, 0x8a20, 0x5202, 0xc460, 0x7525,},    /* 10**4096 */
  {0xa74d, 0x5de4, 0xc53d, 0x3b5d, 0x9e8b, 0x5a92,},    /* 10**2048 */
  {0x650d, 0x0c17, 0x8175, 0x7586, 0xc976, 0x4d48,},
  {0xcc65, 0x91c6, 0xa60e, 0xa0ae, 0xe319, 0x46a3,},
  {0xddbc, 0xde8d, 0x9df9, 0xebfb, 0xaa7e, 0x4351,},
  {0xc66f, 0x8cdf, 0x80e9, 0x47c9, 0x93ba, 0x41a8,},
  {0x3cbf, 0xa6d5, 0xffcf, 0x1f49, 0xc278, 0x40d3,},
  {0xf020, 0xb59d, 0x2b70, 0xada8, 0x9dc5, 0x4069,},
  {0x0000, 0x0000, 0x0400, 0xc9bf, 0x8e1b, 0x4034,},
  {0x0000, 0x0000, 0x0000, 0x2000, 0xbebc, 0x4019,},
  {0x0000, 0x0000, 0x0000, 0x0000, 0x9c40, 0x400c,},
  {0x0000, 0x0000, 0x0000, 0x0000, 0xc800, 0x4005,},
  {0x0000, 0x0000, 0x0000, 0x0000, 0xa000, 0x4002,},    /* 10**1 */
};

static const unsigned short emtens[NTEN + 1][NE] = {
  {0x2de4, 0x9fde, 0xd2ce, 0x04c8, 0xa6dd, 0x0ad8,},    /* 10**-4096 */
  {0x4925, 0x2de4, 0x3436, 0x534f, 0xceae, 0x256b,},    /* 10**-2048 */
  {0x87a6, 0xc0bd, 0xda57, 0x82a5, 0xa2a6, 0x32b5,},
  {0x7133, 0xd21c, 0xdb23, 0xee32, 0x9049, 0x395a,},
  {0xfa91, 0x1939, 0x637a, 0x4325, 0xc031, 0x3cac,},
  {0xac7d, 0xe4a0, 0x64bc, 0x467c, 0xddd0, 0x3e55,},
  {0x3f24, 0xe9a5, 0xa539, 0xea27, 0xa87f, 0x3f2a,},
  {0x67de, 0x94ba, 0x4539, 0x1ead, 0xcfb1, 0x3f94,},
  {0x4c2f, 0xe15b, 0xc44d, 0x94be, 0xe695, 0x3fc9,},
  {0xfdc2, 0xcefc, 0x8461, 0x7711, 0xabcc, 0x3fe4,},
  {0xd3c3, 0x652b, 0xe219, 0x1758, 0xd1b7, 0x3ff1,},
  {0x3d71, 0xd70a, 0x70a3, 0x0a3d, 0xa3d7, 0x3ff8,},
  {0xcccd, 0xcccc, 0xcccc, 0xcccc, 0xcccc, 0x3ffb,},    /* 10**-1 */
};
#endif



/* ASCII string outputs for unix */


#if 0
void
_IO_ldtostr (x, string, ndigs, flags, fmt)
     long double *x;
     char *string;
     int ndigs;
     int flags;
     char fmt;
{
  unsigned short w[NI];
  char *t, *u;
  LDPARMS rnd;
  LDPARMS *ldp = &rnd;

  rnd.rlast = -1;
  rnd.rndprc = NBITS;

  if (sizeof (long double) == 16)
    e113toe ((unsigned short *) x, w, ldp);
  else
    e64toe ((unsigned short *) x, w, ldp);

  etoasc (w, string, ndigs, -1, ldp);
  if (ndigs == 0 && flags == 0)
    {
      /* Delete the decimal point unless alternate format.  */
      t = string;
      while (*t != '.')
        ++t;
      u = t + 1;
      while (*t != '\0')
        *t++ = *u++;
    }
  if (*string == ' ')
    {
      t = string;
      u = t + 1;
      while (*t != '\0')
        *t++ = *u++;
    }
  if (fmt == 'E')
    {
      t = string;
      while (*t != 'e')
        ++t;
      *t = 'E';
    }
}

#endif

/* This routine will not return more than NDEC+1 digits. */

char *
_ldtoa_r (struct _reent *ptr, long double d, int mode, int ndigits,
          int *decpt, int *sign, char **rve)
{
  unsigned short e[NI];
  char *s, *p;
  int i, j, k;
  int orig_ndigits;
  LDPARMS rnd;
  LDPARMS *ldp = &rnd;
  char *outstr;
  char outbuf[NDEC + MAX_EXP_DIGITS + 10];
  union uconv du;
  du.d = d;

  orig_ndigits = ndigits;
  rnd.rlast = -1;
  rnd.rndprc = NBITS;

  _REENT_CHECK_MP (ptr);

/* reentrancy addition to use mprec storage pool */
  if (_REENT_MP_RESULT (ptr))
    {
      _REENT_MP_RESULT (ptr)->_k = _REENT_MP_RESULT_K (ptr);
      _REENT_MP_RESULT (ptr)->_maxwds = 1 << _REENT_MP_RESULT_K (ptr);
      Bfree (ptr, _REENT_MP_RESULT (ptr));
      _REENT_MP_RESULT (ptr) = 0;
    }

#if LDBL_MANT_DIG == 24
  e24toe (&du.pe, e, ldp);
#elif LDBL_MANT_DIG == 53
  e53toe (&du.pe, e, ldp);
#elif LDBL_MANT_DIG == 64
  e64toe (&du.pe, e, ldp);
#else
  e113toe (&du.pe, e, ldp);
#endif

  if (eisneg (e))
    *sign = 1;
  else
    *sign = 0;
/* Mode 3 is "f" format.  */
  if (mode != 3)
    ndigits -= 1;
/* Mode 0 is for %.999 format, which is supposed to give a
   minimum length string that will convert back to the same binary value.
   For now, just ask for 20 digits which is enough but sometimes too many.  */
  if (mode == 0)
    ndigits = 20;

/* This sanity limit must agree with the corresponding one in etoasc, to
   keep straight the returned value of outexpon.  */
  if (ndigits > NDEC)
    ndigits = NDEC;

  etoasc (e, outbuf, ndigits, mode, ldp);
  s = outbuf;
  if (eisinf (e) || eisnan (e))
    {
      *decpt = 9999;
      goto stripspaces;
    }
  *decpt = ldp->outexpon + 1;

/* Transform the string returned by etoasc into what the caller wants.  */

/* Look for decimal point and delete it from the string. */
  s = outbuf;
  while (*s != '\0')
    {
      if (*s == '.')
        goto yesdecpt;
      ++s;
    }
  goto nodecpt;

yesdecpt:

/* Delete the decimal point.  */
  while (*s != '\0')
    {
      *s = *(s + 1);
      ++s;
    }

nodecpt:

/* Back up over the exponent field. */
  while (*s != 'E' && s > outbuf)
    --s;
  *s = '\0';

stripspaces:

/* Strip leading spaces and sign. */
  p = outbuf;
  while (*p == ' ' || *p == '-')
    ++p;

/* Find new end of string.  */
  s = outbuf;
  while ((*s++ = *p++) != '\0')
    ;
  --s;

/* Strip trailing zeros.  */
  if (mode == 2)
    k = 1;
  else if (ndigits > ldp->outexpon)
    k = ndigits;
  else
    k = ldp->outexpon;

  while (*(s - 1) == '0' && ((s - outbuf) > k))
    *(--s) = '\0';

/* In f format, flush small off-scale values to zero.
   Rounding has been taken care of by etoasc. */
  if (mode == 3 && ((ndigits + ldp->outexpon) < 0))
    {
      s = outbuf;
      *s = '\0';
      *decpt = 0;
    }

/* reentrancy addition to use mprec storage pool */
/* we want to have enough space to hold the formatted result */

  if (mode == 3)                /* f format, account for sign + dec digits + decpt + frac */
    i = *decpt + orig_ndigits + 3;
  else                          /* account for sign + max precision digs + E + exp sign + exponent */
    i = orig_ndigits + MAX_EXP_DIGITS + 4;

  j = sizeof (__ULong);
  for (_REENT_MP_RESULT_K (ptr) = 0;
       sizeof (_Bigint) - sizeof (__ULong) + j <= i; j <<= 1)
    _REENT_MP_RESULT_K (ptr)++;
  _REENT_MP_RESULT (ptr) = Balloc (ptr, _REENT_MP_RESULT_K (ptr));

/* Copy from internal temporary buffer to permanent buffer.  */
  outstr = (char *) _REENT_MP_RESULT (ptr);
  strcpy (outstr, outbuf);

  if (rve)
    *rve = outstr + (s - outbuf);

  return outstr;
}

/* Routine used to tell if long double is NaN or Infinity or regular number. 
   Returns:  0 = regular number
             1 = Nan
             2 = Infinity
*/
int
_ldcheck (long double *d)
{
  unsigned short e[NI];
  LDPARMS rnd;
  LDPARMS *ldp = &rnd;

  union uconv du;

  rnd.rlast = -1;
  rnd.rndprc = NBITS;
  du.d = *d;
#if LDBL_MANT_DIG == 24
  e24toe (&du.pe, e, ldp);
#elif LDBL_MANT_DIG == 53
  e53toe (&du.pe, e, ldp);
#elif LDBL_MANT_DIG == 64
  e64toe (&du.pe, e, ldp);
#else
  e113toe (&du.pe, e, ldp);
#endif

  if ((e[NE - 1] & 0x7fff) == 0x7fff)
    {
#ifdef NANS
      if (eisnan (e))
        return (1);
#endif
      return (2);
    }
  else
    return (0);
}                               /* _ldcheck */

static void
etoasc (short unsigned int *x, char *string, int ndigits, int outformat,
        LDPARMS * ldp)
{
  long digit;
  unsigned short y[NI], t[NI], u[NI], w[NI];
  const unsigned short *p, *r, *ten;
  unsigned short sign;
  int i, j, k, expon, rndsav, ndigs;
  char *s, *ss;
  unsigned short m;
  unsigned short *equot = ldp->equot;

  ndigs = ndigits;
  rndsav = ldp->rndprc;
#ifdef NANS
  if (eisnan (x))
    {
      sprintf (string, " NaN ");
      expon = 9999;
      goto bxit;
    }
#endif
  ldp->rndprc = NBITS;          /* set to full precision */
  emov (x, y);                  /* retain external format */
  if (y[NE - 1] & 0x8000)
    {
      sign = 0xffff;
      y[NE - 1] &= 0x7fff;
    }
  else
    {
      sign = 0;
    }
  expon = 0;
  ten = &etens[NTEN][0];
  emov (eone, t);
/* Test for zero exponent */
  if (y[NE - 1] == 0)
    {
      for (k = 0; k < NE - 1; k++)
        {
          if (y[k] != 0)
            goto tnzro;         /* denormalized number */
        }
      goto isone;               /* legal all zeros */
    }
tnzro:

/* Test for infinity.
 */
  if (y[NE - 1] == 0x7fff)
    {
      if (sign)
        sprintf (string, " -Infinity ");
      else
        sprintf (string, " Infinity ");
      expon = 9999;
      goto bxit;
    }

/* Test for exponent nonzero but significand denormalized.
 * This is an error condition.
 */
  if ((y[NE - 1] != 0) && ((y[NE - 2] & 0x8000) == 0))
    {
      mtherr ("etoasc", DOMAIN);
      sprintf (string, "NaN");
      expon = 9999;
      goto bxit;
    }

/* Compare to 1.0 */
  i = ecmp (eone, y);
  if (i == 0)
    goto isone;

  if (i < 0)
    {                           /* Number is greater than 1 */
/* Convert significand to an integer and strip trailing decimal zeros. */
      emov (y, u);
      u[NE - 1] = EXONE + NBITS - 1;

      p = &etens[NTEN - 4][0];
      m = 16;
      do
        {
          ediv (p, u, t, ldp);
          efloor (t, w, ldp);
          for (j = 0; j < NE - 1; j++)
            {
              if (t[j] != w[j])
                goto noint;
            }
          emov (t, u);
          expon += (int) m;
        noint:
          p += NE;
          m >>= 1;
        }
      while (m != 0);

/* Rescale from integer significand */
      u[NE - 1] += y[NE - 1] - (unsigned int) (EXONE + NBITS - 1);
      emov (u, y);
/* Find power of 10 */
      emov (eone, t);
      m = MAXP;
      p = &etens[0][0];
      while (ecmp (ten, u) <= 0)
        {
          if (ecmp (p, u) <= 0)
            {
              ediv (p, u, u, ldp);
              emul (p, t, t, ldp);
              expon += (int) m;
            }
          m >>= 1;
          if (m == 0)
            break;
          p += NE;
        }
    }
  else
    {                           /* Number is less than 1.0 */
/* Pad significand with trailing decimal zeros. */
      if (y[NE - 1] == 0)
        {
          while ((y[NE - 2] & 0x8000) == 0)
            {
              emul (ten, y, y, ldp);
              expon -= 1;
            }
        }
      else
        {
          emovi (y, w);
          for (i = 0; i < NDEC + 1; i++)
            {
              if ((w[NI - 1] & 0x7) != 0)
                break;
/* multiply by 10 */
              emovz (w, u);
              eshdn1 (u);
              eshdn1 (u);
              eaddm (w, u);
              u[1] += 3;
              while (u[2] != 0)
                {
                  eshdn1 (u);
                  u[1] += 1;
                }
              if (u[NI - 1] != 0)
                break;
              if (eone[NE - 1] <= u[1])
                break;
              emovz (u, w);
              expon -= 1;
            }
          emovo (w, y, ldp);
        }
      k = -MAXP;
      p = &emtens[0][0];
      r = &etens[0][0];
      emov (y, w);
      emov (eone, t);
      while (ecmp (eone, w) > 0)
        {
          if (ecmp (p, w) >= 0)
            {
              emul (r, w, w, ldp);
              emul (r, t, t, ldp);
              expon += k;
            }
          k /= 2;
          if (k == 0)
            break;
          p += NE;
          r += NE;
        }
      ediv (t, eone, t, ldp);
    }
isone:
/* Find the first (leading) digit. */
  emovi (t, w);
  emovz (w, t);
  emovi (y, w);
  emovz (w, y);
  eiremain (t, y, ldp);
  digit = equot[NI - 1];
  while ((digit == 0) && (ecmp (y, ezero) != 0))
    {
      eshup1 (y);
      emovz (y, u);
      eshup1 (u);
      eshup1 (u);
      eaddm (u, y);
      eiremain (t, y, ldp);
      digit = equot[NI - 1];
      expon -= 1;
    }
  s = string;
  if (sign)
    *s++ = '-';
  else
    *s++ = ' ';
/* Examine number of digits requested by caller. */
  if (outformat == 3)
    ndigs += expon;
/*
else if( ndigs < 0 )
        ndigs = 0;
*/
  if (ndigs > NDEC)
    ndigs = NDEC;
  if (digit == 10)
    {
      *s++ = '1';
      *s++ = '.';
      if (ndigs > 0)
        {
          *s++ = '0';
          ndigs -= 1;
        }
      expon += 1;
      if (ndigs < 0)
        {
          ss = s;
          goto doexp;
        }
    }
  else
    {
      *s++ = (char) digit + '0';
      *s++ = '.';
    }
/* Generate digits after the decimal point. */
  for (k = 0; k <= ndigs; k++)
    {
/* multiply current number by 10, without normalizing */
      eshup1 (y);
      emovz (y, u);
      eshup1 (u);
      eshup1 (u);
      eaddm (u, y);
      eiremain (t, y, ldp);
      *s++ = (char) equot[NI - 1] + '0';
    }
  digit = equot[NI - 1];
  --s;
  ss = s;
/* round off the ASCII string */
  if (digit > 4)
    {
/* Test for critical rounding case in ASCII output. */
      if (digit == 5)
        {
          emovo (y, t, ldp);
          if (ecmp (t, ezero) != 0)
            goto roun;          /* round to nearest */
          if (ndigs < 0 || (*(s - 1 - (*(s - 1) == '.')) & 1) == 0)
            goto doexp;         /* round to even */
        }
/* Round up and propagate carry-outs */
    roun:
      --s;
      k = *s & 0x7f;
/* Carry out to most significant digit? */
      if (ndigs < 0)
        {
          /* This will print like "1E-6". */
          *s = '1';
          expon += 1;
          goto doexp;
        }
      else if (k == '.')
        {
          --s;
          k = *s;
          k += 1;
          *s = (char) k;
/* Most significant digit carries to 10? */
          if (k > '9')
            {
              expon += 1;
              *s = '1';
            }
          goto doexp;
        }
/* Round up and carry out from less significant digits */
      k += 1;
      *s = (char) k;
      if (k > '9')
        {
          *s = '0';
          goto roun;
        }
    }
doexp:
#ifdef __GO32__
  if (expon >= 0)
    sprintf (ss, "e+%02d", expon);
  else
    sprintf (ss, "e-%02d", -expon);
#else
  sprintf (ss, "E%d", expon);
#endif
bxit:
  ldp->rndprc = rndsav;
  ldp->outexpon = expon;
}


#if 0 /* Broken, unusable implementation of strtold */

/*
;                                                               ASCTOQ
;               ASCTOQ.MAC              LATEST REV: 11 JAN 84
;                                       SLM, 3 JAN 78
;
;       Convert ASCII string to quadruple precision floating point
;
;               Numeric input is free field decimal number
;               with max of 15 digits with or without 
;               decimal point entered as ASCII from teletype.
;       Entering E after the number followed by a second
;       number causes the second number to be interpreted
;       as a power of 10 to be multiplied by the first number
;       (i.e., "scientific" notation).
;
;       Usage:
;               asctoq( string, q );
*/

long double
_strtold (char *s, char **se)
{
  union uconv x;
  LDPARMS rnd;
  LDPARMS *ldp = &rnd;
  int lenldstr;

  rnd.rlast = -1;
  rnd.rndprc = NBITS;

  lenldstr = asctoeg (s, &x.pe, LDBL_MANT_DIG, ldp);
  if (se)
    *se = s + lenldstr;
  return x.d;
}

#define REASONABLE_LEN 200

static int
asctoeg (char *ss, short unsigned int *y, int oprec, LDPARMS * ldp)
{
  unsigned short yy[NI], xt[NI], tt[NI];
  int esign, decflg, sgnflg, nexp, exp, prec, lost;
  int k, trail, c, rndsav;
  long lexp;
  unsigned short nsign;
  const unsigned short *p;
  char *sp, *s, *lstr;
  int lenldstr;
  int mflag = 0;
  char tmpstr[REASONABLE_LEN];

/* Copy the input string. */
  c = strlen (ss) + 2;
  if (c <= REASONABLE_LEN)
    lstr = tmpstr;
  else
    {
      lstr = (char *) calloc (c, 1);
      mflag = 1;
    }
  s = ss;
  lenldstr = 0;
  while (*s == ' ')             /* skip leading spaces */
    {
      ++s;
      ++lenldstr;
    }
  sp = lstr;
  for (k = 0; k < c; k++)
    {
      if ((*sp++ = *s++) == '\0')
        break;
    }
  *sp = '\0';
  s = lstr;

  rndsav = ldp->rndprc;
  ldp->rndprc = NBITS;          /* Set to full precision */
  lost = 0;
  nsign = 0;
  decflg = 0;
  sgnflg = 0;
  nexp = 0;
  exp = 0;
  prec = 0;
  ecleaz (yy);
  trail = 0;

nxtcom:
  k = *s - '0';
  if ((k >= 0) && (k <= 9))
    {
/* Ignore leading zeros */
      if ((prec == 0) && (decflg == 0) && (k == 0))
        goto donchr;
/* Identify and strip trailing zeros after the decimal point. */
      if ((trail == 0) && (decflg != 0))
        {
          sp = s;
          while ((*sp >= '0') && (*sp <= '9'))
            ++sp;
/* Check for syntax error */
          c = *sp & 0x7f;
          if ((c != 'e') && (c != 'E') && (c != '\0')
              && (c != '\n') && (c != '\r') && (c != ' ') && (c != ','))
            goto error;
          --sp;
          while (*sp == '0')
            *sp-- = 'z';
          trail = 1;
          if (*s == 'z')
            goto donchr;
        }
/* If enough digits were given to more than fill up the yy register,
 * continuing until overflow into the high guard word yy[2]
 * guarantees that there will be a roundoff bit at the top
 * of the low guard word after normalization.
 */
      if (yy[2] == 0)
        {
          if (decflg)
            nexp += 1;          /* count digits after decimal point */
          eshup1 (yy);          /* multiply current number by 10 */
          emovz (yy, xt);
          eshup1 (xt);
          eshup1 (xt);
          eaddm (xt, yy);
          ecleaz (xt);
          xt[NI - 2] = (unsigned short) k;
          eaddm (xt, yy);
        }
      else
        {
          /* Mark any lost non-zero digit.  */
          lost |= k;
          /* Count lost digits before the decimal point.  */
          if (decflg == 0)
            nexp -= 1;
        }
      prec += 1;
      goto donchr;
    }

  switch (*s)
    {
    case 'z':
      break;
    case 'E':
    case 'e':
      goto expnt;
    case '.':                   /* decimal point */
      if (decflg)
        goto error;
      ++decflg;
      break;
    case '-':
      nsign = 0xffff;
      if (sgnflg)
        goto error;
      ++sgnflg;
      break;
    case '+':
      if (sgnflg)
        goto error;
      ++sgnflg;
      break;
    case ',':
    case ' ':
    case '\0':
    case '\n':
    case '\r':
      goto daldone;
    case 'i':
    case 'I':
      goto infinite;
    default:
    error:
#ifdef NANS
      enan (yy, NI * 16);
#else
      mtherr ("asctoe", DOMAIN);
      ecleaz (yy);
#endif
      goto aexit;
    }
donchr:
  ++s;
  goto nxtcom;

/* Exponent interpretation */
expnt:

  esign = 1;
  exp = 0;
  ++s;
/* check for + or - */
  if (*s == '-')
    {
      esign = -1;
      ++s;
    }
  if (*s == '+')
    ++s;
  while ((*s >= '0') && (*s <= '9'))
    {
      exp *= 10;
      exp += *s++ - '0';
      if (exp > 4977)
        {
          if (esign < 0)
            goto zero;
          else
            goto infinite;
        }
    }
  if (esign < 0)
    exp = -exp;
  if (exp > 4932)
    {
    infinite:
      ecleaz (yy);
      yy[E] = 0x7fff;           /* infinity */
      goto aexit;
    }
  if (exp < -4977)
    {
    zero:
      ecleaz (yy);
      goto aexit;
    }

daldone:
  nexp = exp - nexp;
/* Pad trailing zeros to minimize power of 10, per IEEE spec. */
  while ((nexp > 0) && (yy[2] == 0))
    {
      emovz (yy, xt);
      eshup1 (xt);
      eshup1 (xt);
      eaddm (yy, xt);
      eshup1 (xt);
      if (xt[2] != 0)
        break;
      nexp -= 1;
      emovz (xt, yy);
    }
  if ((k = enormlz (yy)) > NBITS)
    {
      ecleaz (yy);
      goto aexit;
    }
  lexp = (EXONE - 1 + NBITS) - k;
  emdnorm (yy, lost, 0, lexp, 64, ldp);
/* convert to external format */


/* Multiply by 10**nexp.  If precision is 64 bits,
 * the maximum relative error incurred in forming 10**n
 * for 0 <= n <= 324 is 8.2e-20, at 10**180.
 * For 0 <= n <= 999, the peak relative error is 1.4e-19 at 10**947.
 * For 0 >= n >= -999, it is -1.55e-19 at 10**-435.
 */
  lexp = yy[E];
  if (nexp == 0)
    {
      k = 0;
      goto expdon;
    }
  esign = 1;
  if (nexp < 0)
    {
      nexp = -nexp;
      esign = -1;
      if (nexp > 4096)
        {                       /* Punt.  Can't handle this without 2 divides. */
          emovi (etens[0], tt);
          lexp -= tt[E];
          k = edivm (tt, yy, ldp);
          lexp += EXONE;
          nexp -= 4096;
        }
    }
  p = &etens[NTEN][0];
  emov (eone, xt);
  exp = 1;
  do
    {
      if (exp & nexp)
        emul (p, xt, xt, ldp);
      p -= NE;
      exp = exp + exp;
    }
  while (exp <= MAXP);

  emovi (xt, tt);
  if (esign < 0)
    {
      lexp -= tt[E];
      k = edivm (tt, yy, ldp);
      lexp += EXONE;
    }
  else
    {
      lexp += tt[E];
      k = emulm (tt, yy, ldp);
      lexp -= EXONE - 1;
    }

expdon:

/* Round and convert directly to the destination type */
  if (oprec == 53)
    lexp -= EXONE - 0x3ff;
  else if (oprec == 24)
    lexp -= EXONE - 0177;
#ifdef DEC
  else if (oprec == 56)
    lexp -= EXONE - 0201;
#endif
  ldp->rndprc = oprec;
  emdnorm (yy, k, 0, lexp, 64, ldp);

aexit:

  ldp->rndprc = rndsav;
  yy[0] = nsign;
  switch (oprec)
    {
#ifdef DEC
    case 56:
      todec (yy, y);            /* see etodec.c */
      break;
#endif
#if LDBL_MANT_DIG == 53
    case 53:
      toe53 (yy, y);
      break;
#elif LDBL_MANT_DIG == 24
    case 24:
      toe24 (yy, y);
      break;
#elif LDBL_MANT_DIG == 64
    case 64:
      toe64 (yy, y);
      break;
#elif LDBL_MANT_DIG == 113
    case 113:
      toe113 (yy, y);
      break;
#else
    case NBITS:
      emovo (yy, y, ldp);
      break;
#endif
    }
  lenldstr += s - lstr;
  if (mflag)
    free (lstr);
  return lenldstr;
}

#endif

/* y = largest integer not greater than x
 * (truncated toward minus infinity)
 *
 * unsigned short x[NE], y[NE]
 * LDPARMS *ldp
 *
 * efloor( x, y, ldp );
 */
static const unsigned short bmask[] = {
  0xffff,
  0xfffe,
  0xfffc,
  0xfff8,
  0xfff0,
  0xffe0,
  0xffc0,
  0xff80,
  0xff00,
  0xfe00,
  0xfc00,
  0xf800,
  0xf000,
  0xe000,
  0xc000,
  0x8000,
  0x0000,
};

static void
efloor (short unsigned int *x, short unsigned int *y, LDPARMS * ldp)
{
  register unsigned short *p;
  int e, expon, i;
  unsigned short f[NE];

  emov (x, f);                  /* leave in external format */
  expon = (int) f[NE - 1];
  e = (expon & 0x7fff) - (EXONE - 1);
  if (e <= 0)
    {
      eclear (y);
      goto isitneg;
    }
/* number of bits to clear out */
  e = NBITS - e;
  emov (f, y);
  if (e <= 0)
    return;

  p = &y[0];
  while (e >= 16)
    {
      *p++ = 0;
      e -= 16;
    }
/* clear the remaining bits */
  *p &= bmask[e];
/* truncate negatives toward minus infinity */
isitneg:

  if ((unsigned short) expon & (unsigned short) 0x8000)
    {
      for (i = 0; i < NE - 1; i++)
        {
          if (f[i] != y[i])
            {
              esub (eone, y, y, ldp);
              break;
            }
        }
    }
}



static void
eiremain (short unsigned int *den, short unsigned int *num, LDPARMS * ldp)
{
  long ld, ln;
  unsigned short j;
  unsigned short *equot = ldp->equot;

  ld = den[E];
  ld -= enormlz (den);
  ln = num[E];
  ln -= enormlz (num);
  ecleaz (equot);
  while (ln >= ld)
    {
      if (ecmpm (den, num) <= 0)
        {
          esubm (den, num);
          j = 1;
        }
      else
        {
          j = 0;
        }
      eshup1 (equot);
      equot[NI - 1] |= j;
      eshup1 (num);
      ln -= 1;
    }
  emdnorm (num, 0, 0, ln, 0, ldp);
}

/* NaN bit patterns
 */
#ifdef MIEEE
#if !defined(__mips)
static const unsigned short nan113[8] = {
  0x7fff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff
};

static const unsigned short nan64[6] = {
  0x7fff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff
};
static const unsigned short nan53[4] = { 0x7fff, 0xffff, 0xffff, 0xffff };
static const unsigned short nan24[2] = { 0x7fff, 0xffff };
#elif defined(__mips_nan2008)   /* __mips */
static const unsigned short nan113[8] = { 0x7fff, 0x8000, 0, 0, 0, 0, 0, 0 };
static const unsigned short nan64[6] = { 0x7fff, 0xc000, 0, 0, 0, 0 };
static const unsigned short nan53[4] = { 0x7ff8, 0, 0, 0 };
static const unsigned short nan24[2] = { 0x7fc0, 0 };
#else /* __mips && !__mips_nan2008 */
static const unsigned short nan113[8] = {
  0x7fff, 0x7fff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff
};

static const unsigned short nan64[6] = {
  0x7fff, 0xbfff, 0xffff, 0xffff, 0xffff, 0xffff
};
static const unsigned short nan53[4] = { 0x7ff7, 0xffff, 0xffff, 0xffff };
static const unsigned short nan24[2] = { 0x7fbf, 0xffff };
#endif /* __mips && !__mips_nan2008 */
#else /* !MIEEE */
#if !defined(__mips) || defined(__mips_nan2008)
static const unsigned short nan113[8] = { 0, 0, 0, 0, 0, 0, 0x8000, 0x7fff };
static const unsigned short nan64[6] = { 0, 0, 0, 0, 0xc000, 0x7fff };
static const unsigned short nan53[4] = { 0, 0, 0, 0x7ff8 };
static const unsigned short nan24[2] = { 0, 0x7fc0 };
#else /* __mips && !__mips_nan2008 */
static const unsigned short nan113[8] = {
  0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0x7fff, 0x7fff
};

static const unsigned short nan64[6] = {
  0xffff, 0xffff, 0xffff, 0xffff, 0xbfff, 0x7fff
};
static const unsigned short nan53[4] = { 0xffff, 0xffff, 0xffff, 0x7ff7 };
static const unsigned short nan24[2] = { 0xffff, 0x7fbf };
#endif /* __mips && !__mips_nan2008 */
#endif /* !MIEEE */


static void
enan (short unsigned int *nan, int size)
{
  int i, n;
  const unsigned short *p;

  switch (size)
    {
#ifndef DEC
    case 113:
      n = 8;
      p = nan113;
      break;

    case 64:
      n = 6;
      p = nan64;
      break;

    case 53:
      n = 4;
      p = nan53;
      break;

    case 24:
      n = 2;
      p = nan24;
      break;

    case NBITS:
#if !defined(__mips) || defined(__mips_nan2008)
      for (i = 0; i < NE - 2; i++)
        *nan++ = 0;
      *nan++ = 0xc000;
#else /* __mips && !__mips_nan2008 */
      for (i = 0; i < NE - 2; i++)
        *nan++ = 0xffff;
      *nan++ = 0xbfff;
#endif /* __mips && !__mips_nan2008 */
      *nan++ = 0x7fff;
      return;

    case NI * 16:
      *nan++ = 0;
      *nan++ = 0x7fff;
      *nan++ = 0;
#if !defined(__mips) || defined(__mips_nan2008)
      *nan++ = 0xc000;
      for (i = 4; i < NI - 1; i++)
        *nan++ = 0;
#else /* __mips && !__mips_nan2008 */
      *nan++ = 0xbfff;
      for (i = 4; i < NI - 1; i++)
        *nan++ = 0xffff;
#endif /* __mips && !__mips_nan2008 */
      *nan++ = 0;
      return;
#endif
    default:
      mtherr ("enan", DOMAIN);
      return;
    }
  for (i = 0; i < n; i++)
    *nan++ = *p++;
}