863 lines
18 KiB
C
863 lines
18 KiB
C
/****************************************************************
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*
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* The author of this software is David M. Gay.
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*
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* Copyright (c) 1991 by AT&T.
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*
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* Permission to use, copy, modify, and distribute this software for any
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* purpose without fee is hereby granted, provided that this entire notice
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* is included in all copies of any software which is or includes a copy
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* or modification of this software and in all copies of the supporting
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* documentation for such software.
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*
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* THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR IMPLIED
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* WARRANTY. IN PARTICULAR, NEITHER THE AUTHOR NOR AT&T MAKES ANY
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* REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE MERCHANTABILITY
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* OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR PURPOSE.
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*
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***************************************************************/
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/* Please send bug reports to
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David M. Gay
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AT&T Bell Laboratories, Room 2C-463
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600 Mountain Avenue
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Murray Hill, NJ 07974-2070
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U.S.A.
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dmg@research.att.com or research!dmg
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*/
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#include <_ansi.h>
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#include <stdlib.h>
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#include <reent.h>
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#include <string.h>
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#include "mprec.h"
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static int
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_DEFUN (quorem,
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(b, S),
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_Bigint * b _AND _Bigint * S)
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{
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int n;
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__Long borrow, y;
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__ULong carry, q, ys;
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__ULong *bx, *bxe, *sx, *sxe;
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#ifdef Pack_32
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__Long z;
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__ULong si, zs;
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#endif
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n = S->_wds;
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#ifdef DEBUG
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/*debug*/ if (b->_wds > n)
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/*debug*/ Bug ("oversize b in quorem");
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#endif
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if (b->_wds < n)
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return 0;
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sx = S->_x;
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sxe = sx + --n;
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bx = b->_x;
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bxe = bx + n;
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q = *bxe / (*sxe + 1); /* ensure q <= true quotient */
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#ifdef DEBUG
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/*debug*/ if (q > 9)
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/*debug*/ Bug ("oversized quotient in quorem");
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#endif
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if (q)
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{
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borrow = 0;
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carry = 0;
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do
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{
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#ifdef Pack_32
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si = *sx++;
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ys = (si & 0xffff) * q + carry;
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zs = (si >> 16) * q + (ys >> 16);
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carry = zs >> 16;
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y = (*bx & 0xffff) - (ys & 0xffff) + borrow;
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borrow = y >> 16;
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Sign_Extend (borrow, y);
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z = (*bx >> 16) - (zs & 0xffff) + borrow;
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borrow = z >> 16;
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Sign_Extend (borrow, z);
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Storeinc (bx, z, y);
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#else
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ys = *sx++ * q + carry;
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carry = ys >> 16;
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y = *bx - (ys & 0xffff) + borrow;
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borrow = y >> 16;
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Sign_Extend (borrow, y);
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*bx++ = y & 0xffff;
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#endif
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}
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while (sx <= sxe);
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if (!*bxe)
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{
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bx = b->_x;
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while (--bxe > bx && !*bxe)
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--n;
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b->_wds = n;
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}
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}
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if (cmp (b, S) >= 0)
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{
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q++;
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borrow = 0;
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carry = 0;
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bx = b->_x;
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sx = S->_x;
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do
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{
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#ifdef Pack_32
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si = *sx++;
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ys = (si & 0xffff) + carry;
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zs = (si >> 16) + (ys >> 16);
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carry = zs >> 16;
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y = (*bx & 0xffff) - (ys & 0xffff) + borrow;
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borrow = y >> 16;
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Sign_Extend (borrow, y);
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z = (*bx >> 16) - (zs & 0xffff) + borrow;
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borrow = z >> 16;
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Sign_Extend (borrow, z);
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Storeinc (bx, z, y);
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#else
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ys = *sx++ + carry;
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carry = ys >> 16;
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y = *bx - (ys & 0xffff) + borrow;
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borrow = y >> 16;
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Sign_Extend (borrow, y);
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*bx++ = y & 0xffff;
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#endif
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}
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while (sx <= sxe);
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bx = b->_x;
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bxe = bx + n;
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if (!*bxe)
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{
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while (--bxe > bx && !*bxe)
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--n;
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b->_wds = n;
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}
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}
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return q;
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}
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/* dtoa for IEEE arithmetic (dmg): convert double to ASCII string.
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*
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* Inspired by "How to Print Floating-Point Numbers Accurately" by
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* Guy L. Steele, Jr. and Jon L. White [Proc. ACM SIGPLAN '90, pp. 92-101].
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*
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* Modifications:
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* 1. Rather than iterating, we use a simple numeric overestimate
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* to determine k = floor(log10(d)). We scale relevant
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* quantities using O(log2(k)) rather than O(k) multiplications.
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* 2. For some modes > 2 (corresponding to ecvt and fcvt), we don't
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* try to generate digits strictly left to right. Instead, we
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* compute with fewer bits and propagate the carry if necessary
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* when rounding the final digit up. This is often faster.
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* 3. Under the assumption that input will be rounded nearest,
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* mode 0 renders 1e23 as 1e23 rather than 9.999999999999999e22.
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* That is, we allow equality in stopping tests when the
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* round-nearest rule will give the same floating-point value
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* as would satisfaction of the stopping test with strict
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* inequality.
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* 4. We remove common factors of powers of 2 from relevant
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* quantities.
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* 5. When converting floating-point integers less than 1e16,
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* we use floating-point arithmetic rather than resorting
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* to multiple-precision integers.
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* 6. When asked to produce fewer than 15 digits, we first try
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* to get by with floating-point arithmetic; we resort to
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* multiple-precision integer arithmetic only if we cannot
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* guarantee that the floating-point calculation has given
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* the correctly rounded result. For k requested digits and
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* "uniformly" distributed input, the probability is
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* something like 10^(k-15) that we must resort to the long
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* calculation.
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*/
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char *
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_DEFUN (_dtoa_r,
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(ptr, _d, mode, ndigits, decpt, sign, rve),
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struct _reent *ptr _AND
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double _d _AND
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int mode _AND
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int ndigits _AND
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int *decpt _AND
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int *sign _AND
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char **rve)
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{
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/* Arguments ndigits, decpt, sign are similar to those
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of ecvt and fcvt; trailing zeros are suppressed from
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the returned string. If not null, *rve is set to point
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to the end of the return value. If d is +-Infinity or NaN,
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then *decpt is set to 9999.
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mode:
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0 ==> shortest string that yields d when read in
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and rounded to nearest.
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1 ==> like 0, but with Steele & White stopping rule;
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e.g. with IEEE P754 arithmetic , mode 0 gives
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1e23 whereas mode 1 gives 9.999999999999999e22.
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2 ==> max(1,ndigits) significant digits. This gives a
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return value similar to that of ecvt, except
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that trailing zeros are suppressed.
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3 ==> through ndigits past the decimal point. This
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gives a return value similar to that from fcvt,
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except that trailing zeros are suppressed, and
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ndigits can be negative.
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4-9 should give the same return values as 2-3, i.e.,
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4 <= mode <= 9 ==> same return as mode
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2 + (mode & 1). These modes are mainly for
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debugging; often they run slower but sometimes
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faster than modes 2-3.
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4,5,8,9 ==> left-to-right digit generation.
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6-9 ==> don't try fast floating-point estimate
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(if applicable).
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Values of mode other than 0-9 are treated as mode 0.
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Sufficient space is allocated to the return value
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to hold the suppressed trailing zeros.
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*/
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int bbits, b2, b5, be, dig, i, ieps, ilim, ilim0, ilim1, j, j1, k, k0,
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k_check, leftright, m2, m5, s2, s5, spec_case, try_quick;
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union double_union d, d2, eps;
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__Long L;
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#ifndef Sudden_Underflow
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int denorm;
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__ULong x;
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#endif
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_Bigint *b, *b1, *delta, *mlo = NULL, *mhi, *S;
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double ds;
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char *s, *s0;
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d.d = _d;
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_REENT_CHECK_MP(ptr);
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if (_REENT_MP_RESULT(ptr))
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{
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_REENT_MP_RESULT(ptr)->_k = _REENT_MP_RESULT_K(ptr);
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_REENT_MP_RESULT(ptr)->_maxwds = 1 << _REENT_MP_RESULT_K(ptr);
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Bfree (ptr, _REENT_MP_RESULT(ptr));
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_REENT_MP_RESULT(ptr) = 0;
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}
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if (word0 (d) & Sign_bit)
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{
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/* set sign for everything, including 0's and NaNs */
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*sign = 1;
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word0 (d) &= ~Sign_bit; /* clear sign bit */
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}
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else
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*sign = 0;
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#if defined(IEEE_Arith) + defined(VAX)
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#ifdef IEEE_Arith
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if ((word0 (d) & Exp_mask) == Exp_mask)
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#else
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if (word0 (d) == 0x8000)
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#endif
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{
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/* Infinity or NaN */
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*decpt = 9999;
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s =
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#ifdef IEEE_Arith
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!word1 (d) && !(word0 (d) & 0xfffff) ? "Infinity" :
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#endif
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"NaN";
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if (rve)
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*rve =
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#ifdef IEEE_Arith
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s[3] ? s + 8 :
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#endif
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s + 3;
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return s;
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}
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#endif
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#ifdef IBM
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d.d += 0; /* normalize */
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#endif
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if (!d.d)
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{
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*decpt = 1;
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s = "0";
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if (rve)
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*rve = s + 1;
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return s;
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}
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b = d2b (ptr, d.d, &be, &bbits);
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#ifdef Sudden_Underflow
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i = (int) (word0 (d) >> Exp_shift1 & (Exp_mask >> Exp_shift1));
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#else
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if ((i = (int) (word0 (d) >> Exp_shift1 & (Exp_mask >> Exp_shift1))) != 0)
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{
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#endif
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d2.d = d.d;
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word0 (d2) &= Frac_mask1;
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word0 (d2) |= Exp_11;
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#ifdef IBM
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if (j = 11 - hi0bits (word0 (d2) & Frac_mask))
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d2.d /= 1 << j;
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#endif
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/* log(x) ~=~ log(1.5) + (x-1.5)/1.5
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* log10(x) = log(x) / log(10)
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* ~=~ log(1.5)/log(10) + (x-1.5)/(1.5*log(10))
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* log10(d) = (i-Bias)*log(2)/log(10) + log10(d2)
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*
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* This suggests computing an approximation k to log10(d) by
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*
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* k = (i - Bias)*0.301029995663981
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* + ( (d2-1.5)*0.289529654602168 + 0.176091259055681 );
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*
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* We want k to be too large rather than too small.
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* The error in the first-order Taylor series approximation
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* is in our favor, so we just round up the constant enough
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* to compensate for any error in the multiplication of
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* (i - Bias) by 0.301029995663981; since |i - Bias| <= 1077,
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* and 1077 * 0.30103 * 2^-52 ~=~ 7.2e-14,
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* adding 1e-13 to the constant term more than suffices.
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* Hence we adjust the constant term to 0.1760912590558.
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* (We could get a more accurate k by invoking log10,
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* but this is probably not worthwhile.)
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*/
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i -= Bias;
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#ifdef IBM
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i <<= 2;
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i += j;
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#endif
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#ifndef Sudden_Underflow
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denorm = 0;
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}
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else
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{
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/* d is denormalized */
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i = bbits + be + (Bias + (P - 1) - 1);
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#if defined (_DOUBLE_IS_32BITS)
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x = word0 (d) << (32 - i);
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#else
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x = (i > 32) ? (word0 (d) << (64 - i)) | (word1 (d) >> (i - 32))
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: (word1 (d) << (32 - i));
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#endif
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d2.d = x;
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word0 (d2) -= 31 * Exp_msk1; /* adjust exponent */
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i -= (Bias + (P - 1) - 1) + 1;
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denorm = 1;
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}
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#endif
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#if defined (_DOUBLE_IS_32BITS)
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ds = (d2.d - 1.5) * 0.289529651 + 0.176091269 + i * 0.30103001;
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#else
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ds = (d2.d - 1.5) * 0.289529654602168 + 0.1760912590558 + i * 0.301029995663981;
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#endif
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k = (int) ds;
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if (ds < 0. && ds != k)
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k--; /* want k = floor(ds) */
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k_check = 1;
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if (k >= 0 && k <= Ten_pmax)
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{
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if (d.d < tens[k])
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k--;
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k_check = 0;
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}
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j = bbits - i - 1;
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if (j >= 0)
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{
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b2 = 0;
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s2 = j;
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}
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else
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{
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b2 = -j;
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s2 = 0;
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}
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if (k >= 0)
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{
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b5 = 0;
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s5 = k;
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s2 += k;
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}
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else
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{
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b2 -= k;
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b5 = -k;
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s5 = 0;
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}
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if (mode < 0 || mode > 9)
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mode = 0;
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try_quick = 1;
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if (mode > 5)
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{
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mode -= 4;
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try_quick = 0;
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}
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leftright = 1;
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ilim = ilim1 = -1;
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switch (mode)
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{
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case 0:
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case 1:
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i = 18;
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ndigits = 0;
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break;
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case 2:
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leftright = 0;
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/* no break */
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case 4:
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if (ndigits <= 0)
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ndigits = 1;
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ilim = ilim1 = i = ndigits;
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break;
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case 3:
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leftright = 0;
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/* no break */
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case 5:
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i = ndigits + k + 1;
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ilim = i;
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ilim1 = i - 1;
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if (i <= 0)
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i = 1;
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}
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j = sizeof (__ULong);
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for (_REENT_MP_RESULT_K(ptr) = 0; sizeof (_Bigint) - sizeof (__ULong) + j <= i;
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j <<= 1)
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_REENT_MP_RESULT_K(ptr)++;
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_REENT_MP_RESULT(ptr) = Balloc (ptr, _REENT_MP_RESULT_K(ptr));
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s = s0 = (char *) _REENT_MP_RESULT(ptr);
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if (ilim >= 0 && ilim <= Quick_max && try_quick)
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{
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/* Try to get by with floating-point arithmetic. */
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i = 0;
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d2.d = d.d;
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k0 = k;
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ilim0 = ilim;
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ieps = 2; /* conservative */
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if (k > 0)
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{
|
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ds = tens[k & 0xf];
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j = k >> 4;
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if (j & Bletch)
|
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{
|
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/* prevent overflows */
|
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j &= Bletch - 1;
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d.d /= bigtens[n_bigtens - 1];
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ieps++;
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}
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for (; j; j >>= 1, i++)
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if (j & 1)
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{
|
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ieps++;
|
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ds *= bigtens[i];
|
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}
|
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d.d /= ds;
|
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}
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else if ((j1 = -k) != 0)
|
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{
|
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d.d *= tens[j1 & 0xf];
|
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for (j = j1 >> 4; j; j >>= 1, i++)
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if (j & 1)
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{
|
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ieps++;
|
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d.d *= bigtens[i];
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}
|
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}
|
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if (k_check && d.d < 1. && ilim > 0)
|
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{
|
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if (ilim1 <= 0)
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goto fast_failed;
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ilim = ilim1;
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k--;
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d.d *= 10.;
|
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ieps++;
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}
|
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eps.d = ieps * d.d + 7.;
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word0 (eps) -= (P - 1) * Exp_msk1;
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if (ilim == 0)
|
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{
|
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S = mhi = 0;
|
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d.d -= 5.;
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if (d.d > eps.d)
|
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goto one_digit;
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if (d.d < -eps.d)
|
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goto no_digits;
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goto fast_failed;
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}
|
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#ifndef No_leftright
|
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if (leftright)
|
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{
|
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/* Use Steele & White method of only
|
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* generating digits needed.
|
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*/
|
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eps.d = 0.5 / tens[ilim - 1] - eps.d;
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for (i = 0;;)
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{
|
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L = d.d;
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d.d -= L;
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*s++ = '0' + (int) L;
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if (d.d < eps.d)
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goto ret1;
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if (1. - d.d < eps.d)
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goto bump_up;
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if (++i >= ilim)
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break;
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eps.d *= 10.;
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d.d *= 10.;
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}
|
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}
|
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else
|
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{
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#endif
|
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/* Generate ilim digits, then fix them up. */
|
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eps.d *= tens[ilim - 1];
|
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for (i = 1;; i++, d.d *= 10.)
|
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{
|
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L = d.d;
|
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d.d -= L;
|
|
*s++ = '0' + (int) L;
|
|
if (i == ilim)
|
|
{
|
|
if (d.d > 0.5 + eps.d)
|
|
goto bump_up;
|
|
else if (d.d < 0.5 - eps.d)
|
|
{
|
|
while (*--s == '0');
|
|
s++;
|
|
goto ret1;
|
|
}
|
|
break;
|
|
}
|
|
}
|
|
#ifndef No_leftright
|
|
}
|
|
#endif
|
|
fast_failed:
|
|
s = s0;
|
|
d.d = d2.d;
|
|
k = k0;
|
|
ilim = ilim0;
|
|
}
|
|
|
|
/* Do we have a "small" integer? */
|
|
|
|
if (be >= 0 && k <= Int_max)
|
|
{
|
|
/* Yes. */
|
|
ds = tens[k];
|
|
if (ndigits < 0 && ilim <= 0)
|
|
{
|
|
S = mhi = 0;
|
|
if (ilim < 0 || d.d <= 5 * ds)
|
|
goto no_digits;
|
|
goto one_digit;
|
|
}
|
|
for (i = 1;; i++)
|
|
{
|
|
L = d.d / ds;
|
|
d.d -= L * ds;
|
|
#ifdef Check_FLT_ROUNDS
|
|
/* If FLT_ROUNDS == 2, L will usually be high by 1 */
|
|
if (d.d < 0)
|
|
{
|
|
L--;
|
|
d.d += ds;
|
|
}
|
|
#endif
|
|
*s++ = '0' + (int) L;
|
|
if (i == ilim)
|
|
{
|
|
d.d += d.d;
|
|
if ((d.d > ds) || ((d.d == ds) && (L & 1)))
|
|
{
|
|
bump_up:
|
|
while (*--s == '9')
|
|
if (s == s0)
|
|
{
|
|
k++;
|
|
*s = '0';
|
|
break;
|
|
}
|
|
++*s++;
|
|
}
|
|
break;
|
|
}
|
|
if (!(d.d *= 10.))
|
|
break;
|
|
}
|
|
goto ret1;
|
|
}
|
|
|
|
m2 = b2;
|
|
m5 = b5;
|
|
mhi = mlo = 0;
|
|
if (leftright)
|
|
{
|
|
if (mode < 2)
|
|
{
|
|
i =
|
|
#ifndef Sudden_Underflow
|
|
denorm ? be + (Bias + (P - 1) - 1 + 1) :
|
|
#endif
|
|
#ifdef IBM
|
|
1 + 4 * P - 3 - bbits + ((bbits + be - 1) & 3);
|
|
#else
|
|
1 + P - bbits;
|
|
#endif
|
|
}
|
|
else
|
|
{
|
|
j = ilim - 1;
|
|
if (m5 >= j)
|
|
m5 -= j;
|
|
else
|
|
{
|
|
s5 += j -= m5;
|
|
b5 += j;
|
|
m5 = 0;
|
|
}
|
|
if ((i = ilim) < 0)
|
|
{
|
|
m2 -= i;
|
|
i = 0;
|
|
}
|
|
}
|
|
b2 += i;
|
|
s2 += i;
|
|
mhi = i2b (ptr, 1);
|
|
}
|
|
if (m2 > 0 && s2 > 0)
|
|
{
|
|
i = m2 < s2 ? m2 : s2;
|
|
b2 -= i;
|
|
m2 -= i;
|
|
s2 -= i;
|
|
}
|
|
if (b5 > 0)
|
|
{
|
|
if (leftright)
|
|
{
|
|
if (m5 > 0)
|
|
{
|
|
mhi = pow5mult (ptr, mhi, m5);
|
|
b1 = mult (ptr, mhi, b);
|
|
Bfree (ptr, b);
|
|
b = b1;
|
|
}
|
|
if ((j = b5 - m5) != 0)
|
|
b = pow5mult (ptr, b, j);
|
|
}
|
|
else
|
|
b = pow5mult (ptr, b, b5);
|
|
}
|
|
S = i2b (ptr, 1);
|
|
if (s5 > 0)
|
|
S = pow5mult (ptr, S, s5);
|
|
|
|
/* Check for special case that d is a normalized power of 2. */
|
|
|
|
spec_case = 0;
|
|
if (mode < 2)
|
|
{
|
|
if (!word1 (d) && !(word0 (d) & Bndry_mask)
|
|
#ifndef Sudden_Underflow
|
|
&& word0 (d) & Exp_mask
|
|
#endif
|
|
)
|
|
{
|
|
/* The special case */
|
|
b2 += Log2P;
|
|
s2 += Log2P;
|
|
spec_case = 1;
|
|
}
|
|
}
|
|
|
|
/* Arrange for convenient computation of quotients:
|
|
* shift left if necessary so divisor has 4 leading 0 bits.
|
|
*
|
|
* Perhaps we should just compute leading 28 bits of S once
|
|
* and for all and pass them and a shift to quorem, so it
|
|
* can do shifts and ors to compute the numerator for q.
|
|
*/
|
|
|
|
#ifdef Pack_32
|
|
if ((i = ((s5 ? 32 - hi0bits (S->_x[S->_wds - 1]) : 1) + s2) & 0x1f) != 0)
|
|
i = 32 - i;
|
|
#else
|
|
if ((i = ((s5 ? 32 - hi0bits (S->_x[S->_wds - 1]) : 1) + s2) & 0xf) != 0)
|
|
i = 16 - i;
|
|
#endif
|
|
if (i > 4)
|
|
{
|
|
i -= 4;
|
|
b2 += i;
|
|
m2 += i;
|
|
s2 += i;
|
|
}
|
|
else if (i < 4)
|
|
{
|
|
i += 28;
|
|
b2 += i;
|
|
m2 += i;
|
|
s2 += i;
|
|
}
|
|
if (b2 > 0)
|
|
b = lshift (ptr, b, b2);
|
|
if (s2 > 0)
|
|
S = lshift (ptr, S, s2);
|
|
if (k_check)
|
|
{
|
|
if (cmp (b, S) < 0)
|
|
{
|
|
k--;
|
|
b = multadd (ptr, b, 10, 0); /* we botched the k estimate */
|
|
if (leftright)
|
|
mhi = multadd (ptr, mhi, 10, 0);
|
|
ilim = ilim1;
|
|
}
|
|
}
|
|
if (ilim <= 0 && mode > 2)
|
|
{
|
|
if (ilim < 0 || cmp (b, S = multadd (ptr, S, 5, 0)) <= 0)
|
|
{
|
|
/* no digits, fcvt style */
|
|
no_digits:
|
|
k = -1 - ndigits;
|
|
goto ret;
|
|
}
|
|
one_digit:
|
|
*s++ = '1';
|
|
k++;
|
|
goto ret;
|
|
}
|
|
if (leftright)
|
|
{
|
|
if (m2 > 0)
|
|
mhi = lshift (ptr, mhi, m2);
|
|
|
|
/* Compute mlo -- check for special case
|
|
* that d is a normalized power of 2.
|
|
*/
|
|
|
|
mlo = mhi;
|
|
if (spec_case)
|
|
{
|
|
mhi = Balloc (ptr, mhi->_k);
|
|
Bcopy (mhi, mlo);
|
|
mhi = lshift (ptr, mhi, Log2P);
|
|
}
|
|
|
|
for (i = 1;; i++)
|
|
{
|
|
dig = quorem (b, S) + '0';
|
|
/* Do we yet have the shortest decimal string
|
|
* that will round to d?
|
|
*/
|
|
j = cmp (b, mlo);
|
|
delta = diff (ptr, S, mhi);
|
|
j1 = delta->_sign ? 1 : cmp (b, delta);
|
|
Bfree (ptr, delta);
|
|
#ifndef ROUND_BIASED
|
|
if (j1 == 0 && !mode && !(word1 (d) & 1))
|
|
{
|
|
if (dig == '9')
|
|
goto round_9_up;
|
|
if (j > 0)
|
|
dig++;
|
|
*s++ = dig;
|
|
goto ret;
|
|
}
|
|
#endif
|
|
if ((j < 0) || ((j == 0) && !mode
|
|
#ifndef ROUND_BIASED
|
|
&& !(word1 (d) & 1)
|
|
#endif
|
|
))
|
|
{
|
|
if (j1 > 0)
|
|
{
|
|
b = lshift (ptr, b, 1);
|
|
j1 = cmp (b, S);
|
|
if (((j1 > 0) || ((j1 == 0) && (dig & 1)))
|
|
&& dig++ == '9')
|
|
goto round_9_up;
|
|
}
|
|
*s++ = dig;
|
|
goto ret;
|
|
}
|
|
if (j1 > 0)
|
|
{
|
|
if (dig == '9')
|
|
{ /* possible if i == 1 */
|
|
round_9_up:
|
|
*s++ = '9';
|
|
goto roundoff;
|
|
}
|
|
*s++ = dig + 1;
|
|
goto ret;
|
|
}
|
|
*s++ = dig;
|
|
if (i == ilim)
|
|
break;
|
|
b = multadd (ptr, b, 10, 0);
|
|
if (mlo == mhi)
|
|
mlo = mhi = multadd (ptr, mhi, 10, 0);
|
|
else
|
|
{
|
|
mlo = multadd (ptr, mlo, 10, 0);
|
|
mhi = multadd (ptr, mhi, 10, 0);
|
|
}
|
|
}
|
|
}
|
|
else
|
|
for (i = 1;; i++)
|
|
{
|
|
*s++ = dig = quorem (b, S) + '0';
|
|
if (i >= ilim)
|
|
break;
|
|
b = multadd (ptr, b, 10, 0);
|
|
}
|
|
|
|
/* Round off last digit */
|
|
|
|
b = lshift (ptr, b, 1);
|
|
j = cmp (b, S);
|
|
if ((j > 0) || ((j == 0) && (dig & 1)))
|
|
{
|
|
roundoff:
|
|
while (*--s == '9')
|
|
if (s == s0)
|
|
{
|
|
k++;
|
|
*s++ = '1';
|
|
goto ret;
|
|
}
|
|
++*s++;
|
|
}
|
|
else
|
|
{
|
|
while (*--s == '0');
|
|
s++;
|
|
}
|
|
ret:
|
|
Bfree (ptr, S);
|
|
if (mhi)
|
|
{
|
|
if (mlo && mlo != mhi)
|
|
Bfree (ptr, mlo);
|
|
Bfree (ptr, mhi);
|
|
}
|
|
ret1:
|
|
Bfree (ptr, b);
|
|
*s = 0;
|
|
*decpt = k + 1;
|
|
if (rve)
|
|
*rve = s;
|
|
return s0;
|
|
}
|