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/*

FUNCTION

        <>, <>---string to double or float

INDEX

	strtod

INDEX

	_strtod_r

INDEX

	strtof

ANSI_SYNOPSIS

        #include 

        double strtod(const char *restrict <[str]>, char **restrict <[tail]>);

        float strtof(const char *restrict <[str]>, char **restrict <[tail]>);

        double _strtod_r(void *<[reent]>,

                         const char *restrict <[str]>, char **restrict <[tail]>);

TRAD_SYNOPSIS

        #include 

        double strtod(<[str]>,<[tail]>)

        char *<[str]>;

        char **<[tail]>;

        float strtof(<[str]>,<[tail]>)

        char *<[str]>;

        char **<[tail]>;

        double _strtod_r(<[reent]>,<[str]>,<[tail]>)

	char *<[reent]>;

        char *<[str]>;

        char **<[tail]>;

DESCRIPTION

	The function <> parses the character string <[str]>,

	producing a substring which can be converted to a double

	value.  The substring converted is the longest initial

	subsequence of <[str]>, beginning with the first

	non-whitespace character, that has one of these formats:

	.[+|-]<[digits]>[.[<[digits]>]][(e|E)[+|-]<[digits]>]

	.[+|-].<[digits]>[(e|E)[+|-]<[digits]>]

	.[+|-](i|I)(n|N)(f|F)[(i|I)(n|N)(i|I)(t|T)(y|Y)]

	.[+|-](n|N)(a|A)(n|N)[<(>[<[hexdigits]>]<)>]

	.[+|-]0(x|X)<[hexdigits]>[.[<[hexdigits]>]][(p|P)[+|-]<[digits]>]

	.[+|-]0(x|X).<[hexdigits]>[(p|P)[+|-]<[digits]>]

	The substring contains no characters if <[str]> is empty, consists

	entirely of whitespace, or if the first non-whitespace

	character is something other than <<+>>, <<->>, <<.>>, or a

	digit, and cannot be parsed as infinity or NaN. If the platform

	does not support NaN, then NaN is treated as an empty substring.

	If the substring is empty, no conversion is done, and

	the value of <[str]> is stored in <<*<[tail]>>>.  Otherwise,

	the substring is converted, and a pointer to the final string

	(which will contain at least the terminating null character of

	<[str]>) is stored in <<*<[tail]>>>.  If you want no

	assignment to <<*<[tail]>>>, pass a null pointer as <[tail]>.

	<> is identical to <> except for its return type.

	This implementation returns the nearest machine number to the

	input decimal string.  Ties are broken by using the IEEE

	round-even rule.  However, <> is currently subject to

	double rounding errors.

	The alternate function <<_strtod_r>> is a reentrant version.

	The extra argument <[reent]> is a pointer to a reentrancy structure.

RETURNS

	<> returns the converted substring value, if any.  If

	no conversion could be performed, 0 is returned.  If the

	correct value is out of the range of representable values,

	plus or minus <> is returned, and <> is

	stored in errno. If the correct value would cause underflow, 0

	is returned and <> is stored in errno.

Supporting OS subroutines required: <>, <>, <>,

<>, <>, <>, <>.

*/

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

The author of this software is David M. Gay.

Copyright (C) 1998-2001 by Lucent Technologies

All Rights Reserved

Permission to use, copy, modify, and distribute this software and

its documentation for any purpose and without fee is hereby

granted, provided that the above copyright notice appear in all

copies and that both that the copyright notice and this

permission notice and warranty disclaimer appear in supporting

documentation, and that the name of Lucent or any of its entities

not be used in advertising or publicity pertaining to

distribution of the software without specific, written prior

permission.

LUCENT DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,

INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS.

IN NO EVENT SHALL LUCENT OR ANY OF ITS ENTITIES BE LIABLE FOR ANY

SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES

WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER

IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,

ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF

THIS SOFTWARE.

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

/* Please send bug reports to David M. Gay (dmg at acm dot org,

 * with " at " changed at "@" and " dot " changed to ".").	*/

/* Original file gdtoa-strtod.c Modified 06-21-2006 by Jeff Johnston to work within newlib.  */

#include <_ansi.h>

#include 

#include 

#include 

#include "mprec.h"

#include "gdtoa.h"

#include "gd_qnan.h"

/* #ifndef NO_FENV_H */

/* #include  */

/* #endif */

#include "locale.h"

#ifdef IEEE_Arith

#ifndef NO_IEEE_Scale

#define Avoid_Underflow

#undef tinytens

/* The factor of 2^106 in tinytens[4] helps us avoid setting the underflow */

/* flag unnecessarily.  It leads to a song and dance at the end of strtod. */

static _CONST double tinytens[] = { 1e-16, 1e-32,

#ifdef _DOUBLE_IS_32BITS

				    0.0, 0.0, 0.0

#else

				    1e-64, 1e-128,

				    9007199254740992. * 9007199254740992.e-256

#endif

		};

#endif

#endif

#ifdef Honor_FLT_ROUNDS

#define Rounding rounding

#undef Check_FLT_ROUNDS

#define Check_FLT_ROUNDS

#else

#define Rounding Flt_Rounds

#endif

#ifdef Avoid_Underflow /*{*/

 static double

_DEFUN (sulp, (x, scale),

       	U x _AND

	int scale)

{

        U u;

        double rv;

        int i;

        rv = ulp(dval(x));

        if (!scale || (i = 2*P + 1 - ((dword0(x) & Exp_mask) >> Exp_shift)) <= 0)

                return rv; /* Is there an example where i <= 0 ? */

        dword0(u) = Exp_1 + (i << Exp_shift);

#ifndef _DOUBLE_IS_32BITS

        dword1(u) = 0;

#endif

        return rv * u.d;

        }

#endif /*}*/

#ifndef NO_HEX_FP

static void

_DEFUN (ULtod, (L, bits, exp, k),

	__ULong *L _AND

	__ULong *bits _AND

	Long exp _AND

	int k)

{

	switch(k & STRTOG_Retmask) {

	  case STRTOG_NoNumber:

	  case STRTOG_Zero:

		L[0] = L[1] = 0;

		break;

	  case STRTOG_Denormal:

		L[_1] = bits[0];

		L[_0] = bits[1];

		break;

	  case STRTOG_Normal:

	  case STRTOG_NaNbits:

		L[_1] = bits[0];

		L[_0] = (bits[1] & ~0x100000) | ((exp + 0x3ff + 52) << 20);

		break;

	  case STRTOG_Infinite:

		L[_0] = 0x7ff00000;

		L[_1] = 0;

		break;

	  case STRTOG_NaN:

		L[_0] = 0x7fffffff;

		L[_1] = (__ULong)-1;

	  }

	if (k & STRTOG_Neg)

		L[_0] |= 0x80000000L;

}

#endif /* !NO_HEX_FP */

#ifdef INFNAN_CHECK

static int

_DEFUN (match, (sp, t),

	_CONST char **sp _AND

	char *t)

{

	int c, d;

	_CONST char *s = *sp;

	while( (d = *t++) !=0) {

		if ((c = *++s) >= 'A' && c <= 'Z')

			c += 'a' - 'A';

		if (c != d)

			return 0;

		}

	*sp = s + 1;

	return 1;

}

#endif /* INFNAN_CHECK */

double

_DEFUN (_strtod_r, (ptr, s00, se),

	struct _reent *ptr _AND

	_CONST char *__restrict s00 _AND

	char **__restrict se)

{

#ifdef Avoid_Underflow

	int scale;

#endif

	int bb2, bb5, bbe, bd2, bd5, bbbits, bs2, c, decpt, dsign,

		 e, e1, esign, i, j, k, nd, nd0, nf, nz, nz0, sign;

	_CONST char *s, *s0, *s1;

	double aadj, adj;

	U aadj1, rv, rv0;

	Long L;

	__ULong y, z;

	_Bigint *bb = NULL, *bb1, *bd = NULL, *bd0, *bs = NULL, *delta = NULL;

#ifdef Avoid_Underflow

	__ULong Lsb, Lsb1;

#endif

#ifdef SET_INEXACT

	int inexact, oldinexact;

#endif

#ifdef Honor_FLT_ROUNDS

	int rounding;

#endif

	delta = bs = bd = NULL;

	sign = nz0 = nz = decpt = 0;

	dval(rv) = 0.;

	for(s = s00;;s++) switch(*s) {

		case '-':

			sign = 1;

			/* no break */

		case '+':

			if (*++s)

				goto break2;

			/* no break */

		case 0:

			goto ret0;

		case '\t':

		case '\n':

		case '\v':

		case '\f':

		case '\r':

		case ' ':

			continue;

		default:

			goto break2;

		}

 break2:

	if (*s == '0') {

#ifndef NO_HEX_FP

		{

		static _CONST FPI fpi = { 53, 1-1023-53+1, 2046-1023-53+1, 1, SI };

		Long exp;

		__ULong bits[2];

		switch(s[1]) {

		  case 'x':

		  case 'X':

			/* If the number is not hex, then the parse of

			s00 = s + 1;

			{

#if defined(FE_DOWNWARD) && defined(FE_TONEAREST) && defined(FE_TOWARDZERO) && defined(FE_UPWARD)

			FPI fpi1 = fpi;

			switch(fegetround()) {

			  case FE_TOWARDZERO:	fpi1.rounding = 0; break;

			  case FE_UPWARD:	fpi1.rounding = 2; break;

			  case FE_DOWNWARD:	fpi1.rounding = 3;

			  }

#else

#define fpi1 fpi

#endif

			switch((i = gethex(ptr, &s, &fpi1, &exp, &bb, sign)) & STRTOG_Retmask) {

			  case STRTOG_NoNumber:

				s = s00;

				sign = 0;

				/* FALLTHROUGH */

			  case STRTOG_Zero:

				break;

			  default:

				if (bb) {

					copybits(bits, fpi.nbits, bb);

					Bfree(ptr,bb);

					}

				ULtod(rv.i, bits, exp, i);

			  }}

			goto ret;

		  }

		}

#endif

		nz0 = 1;

		while(*++s == '0') ;

		if (!*s)

			goto ret;

		}

	s0 = s;

	y = z = 0;

	for(nd = nf = 0; (c = *s) >= '0' && c <= '9'; nd++, s++)

			if (nd < 9)

				y = 10*y + c - '0';

			else

				z = 10*z + c - '0';

	nd0 = nd;

	if (strncmp (s, _localeconv_r (ptr)->decimal_point,

		     strlen (_localeconv_r (ptr)->decimal_point)) == 0)

		{

		decpt = 1;

		c = *(s += strlen (_localeconv_r (ptr)->decimal_point));

		if (!nd) {

			for(; c == '0'; c = *++s)

				nz++;

			if (c > '0' && c <= '9') {

				s0 = s;

				nf += nz;

				nz = 0;

				goto have_dig;

				}

			goto dig_done;

			}

		for(; c >= '0' && c <= '9'; c = *++s) {

 have_dig:

			nz++;

			if (c -= '0') {

				nf += nz;

				for(i = 1; i < nz; i++)

					if (nd++ < 9)

							y *= 10;

					else if (nd <= DBL_DIG + 1)

							z *= 10;

				if (nd++ < 9)

						y = 10*y + c;

				else if (nd <= DBL_DIG + 1)

						z = 10*z + c;

				nz = 0;

				}

			}

		}

 dig_done:

	e = 0;

	if (c == 'e' || c == 'E') {

		if (!nd && !nz && !nz0) {

			goto ret0;

			}

		s00 = s;

		esign = 0;

		switch(c = *++s) {

			case '-':

				esign = 1;

			case '+':

				c = *++s;

			}

		if (c >= '0' && c <= '9') {

			while(c == '0')

				c = *++s;

			if (c > '0' && c <= '9') {

				L = c - '0';

				s1 = s;

				while((c = *++s) >= '0' && c <= '9')

					L = 10*L + c - '0';

				if (s - s1 > 8 || L > 19999)

					/* Avoid confusion from exponents

					 * so large that e might overflow.

					 */

					e = 19999; /* safe for 16 bit ints */

				else

					e = (int)L;

				if (esign)

					e = -e;

				}

			else

				e = 0;

			}

		else

			s = s00;

		}

	if (!nd) {

		if (!nz && !nz0) {

#ifdef INFNAN_CHECK

			/* Check for Nan and Infinity */

			__ULong bits[2];

			static _CONST FPI fpinan =	/* only 52 explicit bits */

				{ 52, 1-1023-53+1, 2046-1023-53+1, 1, SI };

			if (!decpt)

			 switch(c) {

			  case 'i':

			  case 'I':

				if (match(&s,"nf")) {

					--s;

					if (!match(&s,"inity"))

						++s;

					dword0(rv) = 0x7ff00000;

#ifndef _DOUBLE_IS_32BITS

					dword1(rv) = 0;

#endif /*!_DOUBLE_IS_32BITS*/

					goto ret;

					}

				break;

			  case 'n':

			  case 'N':

				if (match(&s, "an")) {

#ifndef No_Hex_NaN

					if (*s == '(' /*)*/

					 && hexnan(&s, &fpinan, bits)

							== STRTOG_NaNbits) {

						dword0(rv) = 0x7ff00000 | bits[1];

#ifndef _DOUBLE_IS_32BITS

						dword1(rv) = bits[0];

#endif /*!_DOUBLE_IS_32BITS*/

						}

					else {

#endif

						dword0(rv) = NAN_WORD0;

#ifndef _DOUBLE_IS_32BITS

						dword1(rv) = NAN_WORD1;

#endif /*!_DOUBLE_IS_32BITS*/

#ifndef No_Hex_NaN

						}

#endif

					goto ret;

					}

			  }

#endif /* INFNAN_CHECK */

 ret0:

			s = s00;

			sign = 0;

			}

		goto ret;

		}

	e1 = e -= nf;

	/* Now we have nd0 digits, starting at s0, followed by a

	 * decimal point, followed by nd-nd0 digits.  The number we're

	 * after is the integer represented by those digits times

	 * 10**e */

	if (!nd0)

		nd0 = nd;

	k = nd < DBL_DIG + 1 ? nd : DBL_DIG + 1;

	dval(rv) = y;

	if (k > 9) {

#ifdef SET_INEXACT

		if (k > DBL_DIG)

			oldinexact = get_inexact();

#endif

		dval(rv) = tens[k - 9] * dval(rv) + z;

		}

	bd0 = 0;

	if (nd <= DBL_DIG

#ifndef RND_PRODQUOT

#ifndef Honor_FLT_ROUNDS

		&& Flt_Rounds == 1

#endif

#endif

			) {

		if (!e)

			goto ret;

		if (e > 0) {

			if (e <= Ten_pmax) {

#ifdef VAX

				goto vax_ovfl_check;

#else

#ifdef Honor_FLT_ROUNDS

				/* round correctly FLT_ROUNDS = 2 or 3 */

				if (sign) {

					dval(rv) = -dval(rv);

					sign = 0;

					}

#endif

				/* rv = */ rounded_product(dval(rv), tens[e]);

				goto ret;

#endif

				}

			i = DBL_DIG - nd;

			if (e <= Ten_pmax + i) {

				/* A fancier test would sometimes let us do

				 * this for larger i values.

				 */

#ifdef Honor_FLT_ROUNDS

				/* round correctly FLT_ROUNDS = 2 or 3 */

				if (sign) {

					dval(rv) = -dval(rv);

					sign = 0;

					}

#endif

				e -= i;

				dval(rv) *= tens[i];

#ifdef VAX

				/* VAX exponent range is so narrow we must

				 * worry about overflow here...

				 */

 vax_ovfl_check:

				dword0(rv) -= P*Exp_msk1;

				/* rv = */ rounded_product(dval(rv), tens[e]);

				if ((dword0(rv) & Exp_mask)

				 > Exp_msk1*(DBL_MAX_EXP+Bias-1-P))

					goto ovfl;

				dword0(rv) += P*Exp_msk1;

#else

				/* rv = */ rounded_product(dval(rv), tens[e]);

#endif

				goto ret;

				}

			}

#ifndef Inaccurate_Divide

		else if (e >= -Ten_pmax) {

#ifdef Honor_FLT_ROUNDS

			/* round correctly FLT_ROUNDS = 2 or 3 */

			if (sign) {

				dval(rv) = -dval(rv);

				sign = 0;

				}

#endif

			/* rv = */ rounded_quotient(dval(rv), tens[-e]);

			goto ret;

			}

#endif

		}

	e1 += nd - k;

#ifdef IEEE_Arith

#ifdef SET_INEXACT

	inexact = 1;

	if (k <= DBL_DIG)

		oldinexact = get_inexact();

#endif

#ifdef Avoid_Underflow

	scale = 0;

#endif

#ifdef Honor_FLT_ROUNDS

	if ((rounding = Flt_Rounds) >= 2) {

		if (sign)

			rounding = rounding == 2 ? 0 : 2;

		else

			if (rounding != 2)

				rounding = 0;

		}

#endif

#endif /*IEEE_Arith*/

	/* Get starting approximation = rv * 10**e1 */

	if (e1 > 0) {

		if ( (i = e1 & 15) !=0)

			dval(rv) *= tens[i];

		if (e1 &= ~15) {

			if (e1 > DBL_MAX_10_EXP) {

 ovfl:

#ifndef NO_ERRNO

				ptr->_errno = ERANGE;

#endif

				/* Can't trust HUGE_VAL */

#ifdef IEEE_Arith

#ifdef Honor_FLT_ROUNDS

				switch(rounding) {

				  case 0: /* toward 0 */

				  case 3: /* toward -infinity */

					dword0(rv) = Big0;

#ifndef _DOUBLE_IS_32BITS

					dword1(rv) = Big1;

#endif /*!_DOUBLE_IS_32BITS*/

					break;

				  default:

					dword0(rv) = Exp_mask;

#ifndef _DOUBLE_IS_32BITS

					dword1(rv) = 0;

#endif /*!_DOUBLE_IS_32BITS*/

				  }

#else /*Honor_FLT_ROUNDS*/

				dword0(rv) = Exp_mask;

#ifndef _DOUBLE_IS_32BITS

				dword1(rv) = 0;

#endif /*!_DOUBLE_IS_32BITS*/

#endif /*Honor_FLT_ROUNDS*/

#ifdef SET_INEXACT

				/* set overflow bit */

				dval(rv0) = 1e300;

				dval(rv0) *= dval(rv0);

#endif

#else /*IEEE_Arith*/

				dword0(rv) = Big0;

#ifndef _DOUBLE_IS_32BITS

				dword1(rv) = Big1;

#endif /*!_DOUBLE_IS_32BITS*/

#endif /*IEEE_Arith*/

				if (bd0)

					goto retfree;

				goto ret;

				}

			e1 >>= 4;

			for(j = 0; e1 > 1; j++, e1 >>= 1)

				if (e1 & 1)

					dval(rv) *= bigtens[j];

		/* The last multiplication could overflow. */

			dword0(rv) -= P*Exp_msk1;

			dval(rv) *= bigtens[j];

			if ((z = dword0(rv) & Exp_mask)

			 > Exp_msk1*(DBL_MAX_EXP+Bias-P))

				goto ovfl;

			if (z > Exp_msk1*(DBL_MAX_EXP+Bias-1-P)) {

				/* set to largest number */

				/* (Can't trust DBL_MAX) */

				dword0(rv) = Big0;

#ifndef _DOUBLE_IS_32BITS

				dword1(rv) = Big1;

#endif /*!_DOUBLE_IS_32BITS*/

				}

			else

				dword0(rv) += P*Exp_msk1;

			}

		}

	else if (e1 < 0) {

		e1 = -e1;

		if ( (i = e1 & 15) !=0)

			dval(rv) /= tens[i];

		if (e1 >>= 4) {

			if (e1 >= 1 << n_bigtens)

				goto undfl;

#ifdef Avoid_Underflow

			if (e1 & Scale_Bit)

				scale = 2*P;

			for(j = 0; e1 > 0; j++, e1 >>= 1)

				if (e1 & 1)

					dval(rv) *= tinytens[j];

			if (scale && (j = 2*P + 1 - ((dword0(rv) & Exp_mask)

						>> Exp_shift)) > 0) {

				/* scaled rv is denormal; zap j low bits */

				if (j >= 32) {

#ifndef _DOUBLE_IS_32BITS

					dword1(rv) = 0;

#endif /*!_DOUBLE_IS_32BITS*/

					if (j >= 53)

					 dword0(rv) = (P+2)*Exp_msk1;

					else

					 dword0(rv) &= 0xffffffff << (j-32);

					}

#ifndef _DOUBLE_IS_32BITS

				else

					dword1(rv) &= 0xffffffff << j;

#endif /*!_DOUBLE_IS_32BITS*/

				}

#else

			for(j = 0; e1 > 1; j++, e1 >>= 1)

				if (e1 & 1)

					dval(rv) *= tinytens[j];

			/* The last multiplication could underflow. */

			dval(rv0) = dval(rv);

			dval(rv) *= tinytens[j];

			if (!dval(rv)) {

				dval(rv) = 2.*dval(rv0);

				dval(rv) *= tinytens[j];

#endif

				if (!dval(rv)) {

 undfl:

					dval(rv) = 0.;

#ifndef NO_ERRNO

					ptr->_errno = ERANGE;

#endif

					if (bd0)

						goto retfree;

					goto ret;

					}

#ifndef Avoid_Underflow

#ifndef _DOUBLE_IS_32BITS

				dword0(rv) = Tiny0;

				dword1(rv) = Tiny1;

#else

				dword0(rv) = Tiny1;

#endif /*_DOUBLE_IS_32BITS*/

				/* The refinement below will clean

				 * this approximation up.

				 */

				}

#endif

			}

		}

	/* Now the hard part -- adjusting rv to the correct value.*/

	/* Put digits into bd: true value = bd * 10^e */

	bd0 = s2b(ptr, s0, nd0, nd, y);

	if (bd0 == NULL)

		goto ovfl;

	for(;;) {

		bd = Balloc(ptr,bd0->_k);

		if (bd == NULL)

			goto ovfl;

		Bcopy(bd, bd0);

		bb = d2b(ptr,dval(rv), &bbe, &bbbits);	/* rv = bb * 2^bbe */

		if (bb == NULL)

			goto ovfl;

		bs = i2b(ptr,1);

		if (bs == NULL)

			goto ovfl;

		if (e >= 0) {

			bb2 = bb5 = 0;

			bd2 = bd5 = e;

			}

		else {

			bb2 = bb5 = -e;

			bd2 = bd5 = 0;

			}

		if (bbe >= 0)

			bb2 += bbe;

		else

			bd2 -= bbe;

		bs2 = bb2;

#ifdef Honor_FLT_ROUNDS

		if (rounding != 1)

			bs2++;

#endif

#ifdef Avoid_Underflow

		Lsb = LSB;

		Lsb1 = 0;

		j = bbe - scale;

		i = j + bbbits - 1;	/* logb(rv) */

		j = P + 1 - bbbits;

		if (i < Emin) {	/* denormal */

			i = Emin - i;

			j -= i;

			if (i < 32)

				Lsb <<= i;

		else

				Lsb1 = Lsb << (i-32);

			}

#else /*Avoid_Underflow*/

#ifdef Sudden_Underflow

#ifdef IBM

		j = 1 + 4*P - 3 - bbbits + ((bbe + bbbits - 1) & 3);

#else

		j = P + 1 - bbbits;

#endif

#else /*Sudden_Underflow*/

		j = bbe;

		i = j + bbbits - 1;	/* logb(rv) */

		if (i < Emin)	/* denormal */

			j += P - Emin;

		else

			j = P + 1 - bbbits;

#endif /*Sudden_Underflow*/

#endif /*Avoid_Underflow*/

		bb2 += j;

		bd2 += j;

#ifdef Avoid_Underflow

		bd2 += scale;

#endif

		i = bb2 < bd2 ? bb2 : bd2;

		if (i > bs2)

			i = bs2;

		if (i > 0) {

			bb2 -= i;

			bd2 -= i;

			bs2 -= i;

			}

		if (bb5 > 0) {

			bs = pow5mult(ptr, bs, bb5);

			if (bs == NULL)

				goto ovfl;

			bb1 = mult(ptr, bs, bb);

			if (bb1 == NULL)

				goto ovfl;

			Bfree(ptr, bb);

			bb = bb1;

			}

		if (bb2 > 0) {

			bb = lshift(ptr, bb, bb2);

			if (bb == NULL)

				goto ovfl;

			}

		if (bd5 > 0) {

			bd = pow5mult(ptr, bd, bd5);

			if (bd == NULL)

				goto ovfl;

			}

		if (bd2 > 0) {

			bd = lshift(ptr, bd, bd2);

			if (bd == NULL)

				goto ovfl;

			}

		if (bs2 > 0) {

			bs = lshift(ptr, bs, bs2);

			if (bs == NULL)

				goto ovfl;

			}

		delta = diff(ptr, bb, bd);

		if (delta == NULL)

			goto ovfl;

		dsign = delta->_sign;

		delta->_sign = 0;

		i = cmp(delta, bs);

#ifdef Honor_FLT_ROUNDS

		if (rounding != 1) {

			if (i < 0) {

				/* Error is less than an ulp */

				if (!delta->_x[0] && delta->_wds <= 1) {

					/* exact */

#ifdef SET_INEXACT

					inexact = 0;

#endif

					break;

					}

				if (rounding) {

					if (dsign) {

						adj = 1.;

						goto apply_adj;

						}

					}

				else if (!dsign) {

					adj = -1.;

					if (!dword1(rv)

					 && !(dword0(rv) & Frac_mask)) {

						y = dword0(rv) & Exp_mask;

#ifdef Avoid_Underflow

						if (!scale || y > 2*P*Exp_msk1)

#else

						if (y)

#endif

						  {

						  delta = lshift(ptr, delta,Log2P);

						  if (cmp(delta, bs) <= 0)

							adj = -0.5;

						  }

						}

 apply_adj:

#ifdef Avoid_Underflow

					if (scale && (y = dword0(rv) & Exp_mask)

						<= 2*P*Exp_msk1)

					  dword0(adj) += (2*P+1)*Exp_msk1 - y;

#else

#ifdef Sudden_Underflow

					if ((dword0(rv) & Exp_mask) <=

							P*Exp_msk1) {

						dword0(rv) += P*Exp_msk1;

						dval(rv) += adj*ulp(dval(rv));

						dword0(rv) -= P*Exp_msk1;

						}

					else

#endif /*Sudden_Underflow*/

#endif /*Avoid_Underflow*/

					dval(rv) += adj*ulp(dval(rv));

					}

				break;

				}

			adj = ratio(delta, bs);

			if (adj < 1.)

				adj = 1.;

			if (adj <= 0x7ffffffe) {

				/* adj = rounding ? ceil(adj) : floor(adj); */

				y = adj;

				if (y != adj) {

					if (!((rounding>>1) ^ dsign))

						y++;

					adj = y;

					}

				}

#ifdef Avoid_Underflow

			if (scale && (y = dword0(rv) & Exp_mask) <= 2*P*Exp_msk1)

				dword0(adj) += (2*P+1)*Exp_msk1 - y;

#else

#ifdef Sudden_Underflow

			if ((dword0(rv) & Exp_mask) <= P*Exp_msk1) {

				dword0(rv) += P*Exp_msk1;

				adj *= ulp(dval(rv));

				if (dsign)

					dval(rv) += adj;

				else

					dval(rv) -= adj;

				dword0(rv) -= P*Exp_msk1;

				goto cont;

				}

#endif /*Sudden_Underflow*/

#endif /*Avoid_Underflow*/

			adj *= ulp(dval(rv));

			if (dsign) {

				if (dword0(rv) == Big0 && dword1(rv) == Big1)

					goto ovfl;

				dval(rv) += adj;

			else

				dval(rv) -= adj;

			goto cont;

			}

#endif /*Honor_FLT_ROUNDS*/

		if (i < 0) {

			/* Error is less than half an ulp -- check for

			 * special case of mantissa a power of two.

			 */

			if (dsign || dword1(rv) || dword0(rv) & Bndry_mask

#ifdef IEEE_Arith

#ifdef Avoid_Underflow

			 || (dword0(rv) & Exp_mask) <= (2*P+1)*Exp_msk1

#else

			 || (dword0(rv) & Exp_mask) <= Exp_msk1

#endif

#endif

				) {

#ifdef SET_INEXACT

				if (!delta->x[0] && delta->wds <= 1)

					inexact = 0;

#endif

				break;

				}

			if (!delta->_x[0] && delta->_wds <= 1) {

				/* exact result */

#ifdef SET_INEXACT

				inexact = 0;

#endif

				break;

				}

			delta = lshift(ptr,delta,Log2P);

			if (cmp(delta, bs) > 0)

				goto drop_down;

			break;

			}

		if (i == 0) {

			/* exactly half-way between */

			if (dsign) {

				if ((dword0(rv) & Bndry_mask1) == Bndry_mask1

				 &&  dword1(rv) == (

#ifdef Avoid_Underflow

			(scale && (y = dword0(rv) & Exp_mask) <= 2*P*Exp_msk1)

		? (0xffffffff & (0xffffffff << (2*P+1-(y>>Exp_shift)))) :

#endif

						   0xffffffff)) {

					/*boundary case -- increment exponent*/

					if (dword0(rv) == Big0 && dword1(rv) == Big1)

						goto ovfl;

					dword0(rv) = (dword0(rv) & Exp_mask)

						+ Exp_msk1

#ifdef IBM

						| Exp_msk1 >> 4

#endif

						;

#ifndef _DOUBLE_IS_32BITS

					dword1(rv) = 0;

#endif /*!_DOUBLE_IS_32BITS*/

#ifdef Avoid_Underflow

					dsign = 0;

#endif

					break;

					}

				}

			else if (!(dword0(rv) & Bndry_mask) && !dword1(rv)) {

 drop_down:

				/* boundary case -- decrement exponent */

#ifdef Sudden_Underflow /*{{*/

				L = dword0(rv) & Exp_mask;

#ifdef IBM

				if (L <  Exp_msk1)

#else

#ifdef Avoid_Underflow

				if (L <= (scale ? (2*P+1)*Exp_msk1 : Exp_msk1))

#else

				if (L <= Exp_msk1)

#endif /*Avoid_Underflow*/

#endif /*IBM*/

					goto undfl;

				L -= Exp_msk1;

#else /*Sudden_Underflow}{*/

#ifdef Avoid_Underflow

				if (scale) {

					L = dword0(rv) & Exp_mask;

					if (L <= (2*P+1)*Exp_msk1) {

						if (L > (P+2)*Exp_msk1)

							/* round even ==> */

							/* accept rv */

							break;

						/* rv = smallest denormal */

						goto undfl;

						}

					}

#endif /*Avoid_Underflow*/

				L = (dword0(rv) & Exp_mask) - Exp_msk1;

#endif /*Sudden_Underflow}*/

				dword0(rv) = L | Bndry_mask1;

#ifndef _DOUBLE_IS_32BITS

				dword1(rv) = 0xffffffff;

#endif /*!_DOUBLE_IS_32BITS*/

#ifdef IBM

				goto cont;

#else

				break;

#endif

				}

#ifndef ROUND_BIASED

#ifdef Avoid_Underflow

			if (Lsb1) {

				if (!(dword0(rv) & Lsb1))

					break;

				}

			else if (!(dword1(rv) & Lsb))

				break;

#else

			if (!(dword1(rv) & LSB))

				break;

#endif

#endif

			if (dsign)

#ifdef Avoid_Underflow

				dval(rv) += sulp(rv, scale);

#else

				dval(rv) += ulp(dval(rv));

#endif

#ifndef ROUND_BIASED

			else {

#ifdef Avoid_Underflow

				dval(rv) -= sulp(rv, scale);

#else

				dval(rv) -= ulp(dval(rv));

#endif

#ifndef Sudden_Underflow

				if (!dval(rv))

					goto undfl;

#endif

				}

#ifdef Avoid_Underflow

			dsign = 1 - dsign;

#endif

#endif

			break;

			}

		if ((aadj = ratio(delta, bs)) <= 2.) {

			if (dsign)

				aadj = dval(aadj1) = 1.;

			else if (dword1(rv) || dword0(rv) & Bndry_mask) {

#ifndef Sudden_Underflow

				if (dword1(rv) == Tiny1 && !dword0(rv))

					goto undfl;

#endif

				aadj = 1.;

				dval(aadj1) = -1.;

				}

			else {

				/* special case -- power of FLT_RADIX to be */

				/* rounded down... */

				if (aadj < 2./FLT_RADIX)

					aadj = 1./FLT_RADIX;

				else

					aadj *= 0.5;

				dval(aadj1) = -aadj;

				}

			}

		else {

			aadj *= 0.5;

			dval(aadj1) = dsign ? aadj : -aadj;

#ifdef Check_FLT_ROUNDS

			switch(Rounding) {

				case 2: /* towards +infinity */

					dval(aadj1) -= 0.5;

					break;

				case 0: /* towards 0 */

				case 3: /* towards -infinity */

					dval(aadj1) += 0.5;

				}

#else

			if (Flt_Rounds == 0)

				dval(aadj1) += 0.5;

#endif /*Check_FLT_ROUNDS*/

			}

		y = dword0(rv) & Exp_mask;

		/* Check for overflow */

		if (y == Exp_msk1*(DBL_MAX_EXP+Bias-1)) {

			dval(rv0) = dval(rv);

			dword0(rv) -= P*Exp_msk1;

			adj = dval(aadj1) * ulp(dval(rv));

			dval(rv) += adj;

			if ((dword0(rv) & Exp_mask) >=

					Exp_msk1*(DBL_MAX_EXP+Bias-P)) {

				if (dword0(rv0) == Big0 && dword1(rv0) == Big1)

					goto ovfl;

				dword0(rv) = Big0;

#ifndef _DOUBLE_IS_32BITS