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mirror of git://sourceware.org/git/newlib-cygwin.git synced 2025-01-21 05:49:19 +08:00
Matt Joyce ea99f21ce6 Add --enable-newlib-reent-thread-local option
By default, Newlib uses a huge object of type struct _reent to store
thread-specific data.  This object is returned by __getreent() if the
__DYNAMIC_REENT__ Newlib configuration option is defined.

The reentrancy structure contains for example errno and the standard input,
output, and error file streams.  This means that if an application only uses
errno it has a dependency on the file stream support even if it does not use
it.  This is an issue for lower end targets and applications which need to
qualify the software according to safety standards (for example ECSS-E-ST-40C,
ECSS-Q-ST-80C, IEC 61508, ISO 26262, DO-178, DO-330, DO-333).

If the new _REENT_THREAD_LOCAL configuration option is enabled, then struct
_reent is replaced by dedicated thread-local objects for each struct _reent
member.  The thread-local objects are defined in translation units which use
the corresponding object.
2022-07-13 06:55:46 +02:00

1045 lines
19 KiB
C

/****************************************************************
*
* The author of this software is David M. Gay.
*
* Copyright (c) 1991 by AT&T.
*
* Permission to use, copy, modify, and distribute this software for any
* purpose without fee is hereby granted, provided that this entire notice
* is included in all copies of any software which is or includes a copy
* or modification of this software and in all copies of the supporting
* documentation for such software.
*
* THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR IMPLIED
* WARRANTY. IN PARTICULAR, NEITHER THE AUTHOR NOR AT&T MAKES ANY
* REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE MERCHANTABILITY
* OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR PURPOSE.
*
***************************************************************/
/* Please send bug reports to
David M. Gay
AT&T Bell Laboratories, Room 2C-463
600 Mountain Avenue
Murray Hill, NJ 07974-2070
U.S.A.
dmg@research.att.com or research!dmg
*/
/* strtod for IEEE-, VAX-, and IBM-arithmetic machines.
*
* This strtod returns a nearest machine number to the input decimal
* string (or sets errno to ERANGE). With IEEE arithmetic, ties are
* broken by the IEEE round-even rule. Otherwise ties are broken by
* biased rounding (add half and chop).
*
* Inspired loosely by William D. Clinger's paper "How to Read Floating
* Point Numbers Accurately" [Proc. ACM SIGPLAN '90, pp. 92-101].
*
* Modifications:
*
* 1. We only require IEEE, IBM, or VAX double-precision
* arithmetic (not IEEE double-extended).
* 2. We get by with floating-point arithmetic in a case that
* Clinger missed -- when we're computing d * 10^n
* for a small integer d and the integer n is not too
* much larger than 22 (the maximum integer k for which
* we can represent 10^k exactly), we may be able to
* compute (d*10^k) * 10^(e-k) with just one roundoff.
* 3. Rather than a bit-at-a-time adjustment of the binary
* result in the hard case, we use floating-point
* arithmetic to determine the adjustment to within
* one bit; only in really hard cases do we need to
* compute a second residual.
* 4. Because of 3., we don't need a large table of powers of 10
* for ten-to-e (just some small tables, e.g. of 10^k
* for 0 <= k <= 22).
*/
/*
* #define IEEE_8087 for IEEE-arithmetic machines where the least
* significant byte has the lowest address.
* #define IEEE_MC68k for IEEE-arithmetic machines where the most
* significant byte has the lowest address.
* #define Sudden_Underflow for IEEE-format machines without gradual
* underflow (i.e., that flush to zero on underflow).
* #define IBM for IBM mainframe-style floating-point arithmetic.
* #define VAX for VAX-style floating-point arithmetic.
* #define Unsigned_Shifts if >> does treats its left operand as unsigned.
* #define No_leftright to omit left-right logic in fast floating-point
* computation of dtoa.
* #define Check_FLT_ROUNDS if FLT_ROUNDS can assume the values 2 or 3.
* #define RND_PRODQUOT to use rnd_prod and rnd_quot (assembly routines
* that use extended-precision instructions to compute rounded
* products and quotients) with IBM.
* #define ROUND_BIASED for IEEE-format with biased rounding.
* #define Inaccurate_Divide for IEEE-format with correctly rounded
* products but inaccurate quotients, e.g., for Intel i860.
* #define Just_16 to store 16 bits per 32-bit long when doing high-precision
* integer arithmetic. Whether this speeds things up or slows things
* down depends on the machine and the number being converted.
*/
#include <_ansi.h>
#include <stdlib.h>
#include <string.h>
#include <reent.h>
#include "mprec.h"
#ifdef _REENT_THREAD_LOCAL
_Thread_local struct _Bigint *_tls_mp_p5s;
_Thread_local struct _Bigint **_tls_mp_freelist;
#endif
/* This is defined in sys/reent.h as (sizeof (size_t) << 3) now, as in NetBSD.
The old value of 15 was wrong and made newlib vulnerable against buffer
overrun attacks (CVE-2009-0689), same as other implementations of gdtoa
based on BSD code.
#define _Kmax 15
*/
_Bigint *
Balloc (struct _reent *ptr, int k)
{
int x;
_Bigint *rv ;
_REENT_CHECK_MP(ptr);
if (_REENT_MP_FREELIST(ptr) == NULL)
{
/* Allocate a list of pointers to the mprec objects */
_REENT_MP_FREELIST(ptr) = (struct _Bigint **) _calloc_r (ptr,
sizeof (struct _Bigint *),
_Kmax + 1);
if (_REENT_MP_FREELIST(ptr) == NULL)
{
return NULL;
}
}
if ((rv = _REENT_MP_FREELIST(ptr)[k]) != 0)
{
_REENT_MP_FREELIST(ptr)[k] = rv->_next;
}
else
{
x = 1 << k;
/* Allocate an mprec Bigint and stick in in the freelist */
rv = (_Bigint *) _calloc_r (ptr,
1,
sizeof (_Bigint) +
(x-1) * sizeof(rv->_x));
if (rv == NULL) return NULL;
rv->_k = k;
rv->_maxwds = x;
}
rv->_sign = rv->_wds = 0;
return rv;
}
void
Bfree (struct _reent *ptr, _Bigint * v)
{
_REENT_CHECK_MP(ptr);
if (v)
{
v->_next = _REENT_MP_FREELIST(ptr)[v->_k];
_REENT_MP_FREELIST(ptr)[v->_k] = v;
}
}
_Bigint *
multadd (struct _reent *ptr,
_Bigint * b,
int m,
int a)
{
int i, wds;
__ULong *x, y;
#ifdef Pack_32
__ULong xi, z;
#endif
_Bigint *b1;
wds = b->_wds;
x = b->_x;
i = 0;
do
{
#ifdef Pack_32
xi = *x;
y = (xi & 0xffff) * m + a;
z = (xi >> 16) * m + (y >> 16);
a = (int) (z >> 16);
*x++ = (z << 16) + (y & 0xffff);
#else
y = *x * m + a;
a = (int) (y >> 16);
*x++ = y & 0xffff;
#endif
}
while (++i < wds);
if (a)
{
if (wds >= b->_maxwds)
{
b1 = eBalloc (ptr, b->_k + 1);
Bcopy (b1, b);
Bfree (ptr, b);
b = b1;
}
b->_x[wds++] = a;
b->_wds = wds;
}
return b;
}
_Bigint *
s2b (struct _reent * ptr,
const char *s,
int nd0,
int nd,
__ULong y9)
{
_Bigint *b;
int i, k;
__Long x, y;
x = (nd + 8) / 9;
for (k = 0, y = 1; x > y; y <<= 1, k++);
#ifdef Pack_32
b = eBalloc (ptr, k);
b->_x[0] = y9;
b->_wds = 1;
#else
b = eBalloc (ptr, k + 1);
b->_x[0] = y9 & 0xffff;
b->_wds = (b->_x[1] = y9 >> 16) ? 2 : 1;
#endif
i = 9;
if (9 < nd0)
{
s += 9;
do
b = multadd (ptr, b, 10, *s++ - '0');
while (++i < nd0);
s++;
}
else
s += 10;
for (; i < nd; i++)
b = multadd (ptr, b, 10, *s++ - '0');
return b;
}
int
hi0bits (register __ULong x)
{
register int k = 0;
if (!(x & 0xffff0000))
{
k = 16;
x <<= 16;
}
if (!(x & 0xff000000))
{
k += 8;
x <<= 8;
}
if (!(x & 0xf0000000))
{
k += 4;
x <<= 4;
}
if (!(x & 0xc0000000))
{
k += 2;
x <<= 2;
}
if (!(x & 0x80000000))
{
k++;
if (!(x & 0x40000000))
return 32;
}
return k;
}
int
lo0bits (__ULong *y)
{
register int k;
register __ULong x = *y;
if (x & 7)
{
if (x & 1)
return 0;
if (x & 2)
{
*y = x >> 1;
return 1;
}
*y = x >> 2;
return 2;
}
k = 0;
if (!(x & 0xffff))
{
k = 16;
x >>= 16;
}
if (!(x & 0xff))
{
k += 8;
x >>= 8;
}
if (!(x & 0xf))
{
k += 4;
x >>= 4;
}
if (!(x & 0x3))
{
k += 2;
x >>= 2;
}
if (!(x & 1))
{
k++;
x >>= 1;
if (!x & 1)
return 32;
}
*y = x;
return k;
}
_Bigint *
i2b (struct _reent * ptr, int i)
{
_Bigint *b;
b = eBalloc (ptr, 1);
b->_x[0] = i;
b->_wds = 1;
return b;
}
_Bigint *
mult (struct _reent * ptr, _Bigint * a, _Bigint * b)
{
_Bigint *c;
int k, wa, wb, wc;
__ULong carry, y, z;
__ULong *x, *xa, *xae, *xb, *xbe, *xc, *xc0;
#ifdef Pack_32
__ULong z2;
#endif
if (a->_wds < b->_wds)
{
c = a;
a = b;
b = c;
}
k = a->_k;
wa = a->_wds;
wb = b->_wds;
wc = wa + wb;
if (wc > a->_maxwds)
k++;
c = eBalloc (ptr, k);
for (x = c->_x, xa = x + wc; x < xa; x++)
*x = 0;
xa = a->_x;
xae = xa + wa;
xb = b->_x;
xbe = xb + wb;
xc0 = c->_x;
#ifdef Pack_32
for (; xb < xbe; xb++, xc0++)
{
if ((y = *xb & 0xffff) != 0)
{
x = xa;
xc = xc0;
carry = 0;
do
{
z = (*x & 0xffff) * y + (*xc & 0xffff) + carry;
carry = z >> 16;
z2 = (*x++ >> 16) * y + (*xc >> 16) + carry;
carry = z2 >> 16;
Storeinc (xc, z2, z);
}
while (x < xae);
*xc = carry;
}
if ((y = *xb >> 16) != 0)
{
x = xa;
xc = xc0;
carry = 0;
z2 = *xc;
do
{
z = (*x & 0xffff) * y + (*xc >> 16) + carry;
carry = z >> 16;
Storeinc (xc, z, z2);
z2 = (*x++ >> 16) * y + (*xc & 0xffff) + carry;
carry = z2 >> 16;
}
while (x < xae);
*xc = z2;
}
}
#else
for (; xb < xbe; xc0++)
{
if (y = *xb++)
{
x = xa;
xc = xc0;
carry = 0;
do
{
z = *x++ * y + *xc + carry;
carry = z >> 16;
*xc++ = z & 0xffff;
}
while (x < xae);
*xc = carry;
}
}
#endif
for (xc0 = c->_x, xc = xc0 + wc; wc > 0 && !*--xc; --wc);
c->_wds = wc;
return c;
}
_Bigint *
pow5mult (struct _reent * ptr, _Bigint * b, int k)
{
_Bigint *b1, *p5, *p51;
int i;
static const int p05[3] = {5, 25, 125};
if ((i = k & 3) != 0)
b = multadd (ptr, b, p05[i - 1], 0);
if (!(k >>= 2))
return b;
_REENT_CHECK_MP(ptr);
if (!(p5 = _REENT_MP_P5S(ptr)))
{
/* first time */
p5 = _REENT_MP_P5S(ptr) = i2b (ptr, 625);
p5->_next = 0;
}
for (;;)
{
if (k & 1)
{
b1 = mult (ptr, b, p5);
Bfree (ptr, b);
b = b1;
}
if (!(k >>= 1))
break;
if (!(p51 = p5->_next))
{
p51 = p5->_next = mult (ptr, p5, p5);
p51->_next = 0;
}
p5 = p51;
}
return b;
}
_Bigint *
lshift (struct _reent * ptr, _Bigint * b, int k)
{
int i, k1, n, n1;
_Bigint *b1;
__ULong *x, *x1, *xe, z;
#ifdef Pack_32
n = k >> 5;
#else
n = k >> 4;
#endif
k1 = b->_k;
n1 = n + b->_wds + 1;
for (i = b->_maxwds; n1 > i; i <<= 1)
k1++;
b1 = eBalloc (ptr, k1);
x1 = b1->_x;
for (i = 0; i < n; i++)
*x1++ = 0;
x = b->_x;
xe = x + b->_wds;
#ifdef Pack_32
if (k &= 0x1f)
{
k1 = 32 - k;
z = 0;
do
{
*x1++ = *x << k | z;
z = *x++ >> k1;
}
while (x < xe);
if ((*x1 = z) != 0)
++n1;
}
#else
if (k &= 0xf)
{
k1 = 16 - k;
z = 0;
do
{
*x1++ = *x << k & 0xffff | z;
z = *x++ >> k1;
}
while (x < xe);
if (*x1 = z)
++n1;
}
#endif
else
do
*x1++ = *x++;
while (x < xe);
b1->_wds = n1 - 1;
Bfree (ptr, b);
return b1;
}
int
cmp (_Bigint * a, _Bigint * b)
{
__ULong *xa, *xa0, *xb, *xb0;
int i, j;
i = a->_wds;
j = b->_wds;
#ifdef DEBUG
if (i > 1 && !a->_x[i - 1])
Bug ("cmp called with a->_x[a->_wds-1] == 0");
if (j > 1 && !b->_x[j - 1])
Bug ("cmp called with b->_x[b->_wds-1] == 0");
#endif
if (i -= j)
return i;
xa0 = a->_x;
xa = xa0 + j;
xb0 = b->_x;
xb = xb0 + j;
for (;;)
{
if (*--xa != *--xb)
return *xa < *xb ? -1 : 1;
if (xa <= xa0)
break;
}
return 0;
}
_Bigint *
diff (struct _reent * ptr,
_Bigint * a, _Bigint * b)
{
_Bigint *c;
int i, wa, wb;
__Long borrow, y; /* We need signed shifts here. */
__ULong *xa, *xae, *xb, *xbe, *xc;
#ifdef Pack_32
__Long z;
#endif
i = cmp (a, b);
if (!i)
{
c = eBalloc (ptr, 0);
c->_wds = 1;
c->_x[0] = 0;
return c;
}
if (i < 0)
{
c = a;
a = b;
b = c;
i = 1;
}
else
i = 0;
c = eBalloc (ptr, a->_k);
c->_sign = i;
wa = a->_wds;
xa = a->_x;
xae = xa + wa;
wb = b->_wds;
xb = b->_x;
xbe = xb + wb;
xc = c->_x;
borrow = 0;
#ifdef Pack_32
do
{
y = (*xa & 0xffff) - (*xb & 0xffff) + borrow;
borrow = y >> 16;
Sign_Extend (borrow, y);
z = (*xa++ >> 16) - (*xb++ >> 16) + borrow;
borrow = z >> 16;
Sign_Extend (borrow, z);
Storeinc (xc, z, y);
}
while (xb < xbe);
while (xa < xae)
{
y = (*xa & 0xffff) + borrow;
borrow = y >> 16;
Sign_Extend (borrow, y);
z = (*xa++ >> 16) + borrow;
borrow = z >> 16;
Sign_Extend (borrow, z);
Storeinc (xc, z, y);
}
#else
do
{
y = *xa++ - *xb++ + borrow;
borrow = y >> 16;
Sign_Extend (borrow, y);
*xc++ = y & 0xffff;
}
while (xb < xbe);
while (xa < xae)
{
y = *xa++ + borrow;
borrow = y >> 16;
Sign_Extend (borrow, y);
*xc++ = y & 0xffff;
}
#endif
while (!*--xc)
wa--;
c->_wds = wa;
return c;
}
double
ulp (double _x)
{
union double_union x, a;
register __Long L;
x.d = _x;
L = (word0 (x) & Exp_mask) - (P - 1) * Exp_msk1;
#ifndef Sudden_Underflow
if (L > 0)
{
#endif
#ifdef IBM
L |= Exp_msk1 >> 4;
#endif
word0 (a) = L;
#ifndef _DOUBLE_IS_32BITS
word1 (a) = 0;
#endif
#ifndef Sudden_Underflow
}
else
{
L = -L >> Exp_shift;
if (L < Exp_shift)
{
word0 (a) = 0x80000 >> L;
#ifndef _DOUBLE_IS_32BITS
word1 (a) = 0;
#endif
}
else
{
word0 (a) = 0;
L -= Exp_shift;
#ifndef _DOUBLE_IS_32BITS
word1 (a) = L >= 31 ? 1 : 1 << (31 - L);
#endif
}
}
#endif
return a.d;
}
double
b2d (_Bigint * a, int *e)
{
__ULong *xa, *xa0, w, y, z;
int k;
union double_union d;
#ifdef VAX
__ULong d0, d1;
#else
#define d0 word0(d)
#define d1 word1(d)
#endif
xa0 = a->_x;
xa = xa0 + a->_wds;
y = *--xa;
#ifdef DEBUG
if (!y)
Bug ("zero y in b2d");
#endif
k = hi0bits (y);
*e = 32 - k;
#ifdef Pack_32
if (k < Ebits)
{
d0 = Exp_1 | y >> (Ebits - k);
w = xa > xa0 ? *--xa : 0;
#ifndef _DOUBLE_IS_32BITS
d1 = y << ((32 - Ebits) + k) | w >> (Ebits - k);
#endif
goto ret_d;
}
z = xa > xa0 ? *--xa : 0;
if (k -= Ebits)
{
d0 = Exp_1 | y << k | z >> (32 - k);
y = xa > xa0 ? *--xa : 0;
#ifndef _DOUBLE_IS_32BITS
d1 = z << k | y >> (32 - k);
#endif
}
else
{
d0 = Exp_1 | y;
#ifndef _DOUBLE_IS_32BITS
d1 = z;
#endif
}
#else
if (k < Ebits + 16)
{
z = xa > xa0 ? *--xa : 0;
d0 = Exp_1 | y << k - Ebits | z >> Ebits + 16 - k;
w = xa > xa0 ? *--xa : 0;
y = xa > xa0 ? *--xa : 0;
d1 = z << k + 16 - Ebits | w << k - Ebits | y >> 16 + Ebits - k;
goto ret_d;
}
z = xa > xa0 ? *--xa : 0;
w = xa > xa0 ? *--xa : 0;
k -= Ebits + 16;
d0 = Exp_1 | y << k + 16 | z << k | w >> 16 - k;
y = xa > xa0 ? *--xa : 0;
d1 = w << k + 16 | y << k;
#endif
ret_d:
#ifdef VAX
word0 (d) = d0 >> 16 | d0 << 16;
word1 (d) = d1 >> 16 | d1 << 16;
#else
#undef d0
#undef d1
#endif
return d.d;
}
_Bigint *
d2b (struct _reent * ptr,
double _d,
int *e,
int *bits)
{
union double_union d;
_Bigint *b;
int de, i, k;
__ULong *x, y, z;
#ifdef VAX
__ULong d0, d1;
#endif
d.d = _d;
#ifdef VAX
d0 = word0 (d) >> 16 | word0 (d) << 16;
d1 = word1 (d) >> 16 | word1 (d) << 16;
#else
#define d0 word0(d)
#define d1 word1(d)
d.d = _d;
#endif
#ifdef Pack_32
b = eBalloc (ptr, 1);
#else
b = eBalloc (ptr, 2);
#endif
x = b->_x;
z = d0 & Frac_mask;
d0 &= 0x7fffffff; /* clear sign bit, which we ignore */
#ifdef Sudden_Underflow
de = (int) (d0 >> Exp_shift);
#ifndef IBM
z |= Exp_msk11;
#endif
#else
if ((de = (int) (d0 >> Exp_shift)) != 0)
z |= Exp_msk1;
#endif
#ifdef Pack_32
#ifndef _DOUBLE_IS_32BITS
if (d1)
{
y = d1;
k = lo0bits (&y);
if (k)
{
x[0] = y | z << (32 - k);
z >>= k;
}
else
x[0] = y;
i = b->_wds = (x[1] = z) ? 2 : 1;
}
else
#endif
{
#ifdef DEBUG
if (!z)
Bug ("Zero passed to d2b");
#endif
k = lo0bits (&z);
x[0] = z;
i = b->_wds = 1;
#ifndef _DOUBLE_IS_32BITS
k += 32;
#endif
}
#else
if (d1)
{
y = d1;
k = lo0bits (&y);
if (k)
if (k >= 16)
{
x[0] = y | z << 32 - k & 0xffff;
x[1] = z >> k - 16 & 0xffff;
x[2] = z >> k;
i = 2;
}
else
{
x[0] = y & 0xffff;
x[1] = y >> 16 | z << 16 - k & 0xffff;
x[2] = z >> k & 0xffff;
x[3] = z >> k + 16;
i = 3;
}
else
{
x[0] = y & 0xffff;
x[1] = y >> 16;
x[2] = z & 0xffff;
x[3] = z >> 16;
i = 3;
}
}
else
{
#ifdef DEBUG
if (!z)
Bug ("Zero passed to d2b");
#endif
k = lo0bits (&z);
if (k >= 16)
{
x[0] = z;
i = 0;
}
else
{
x[0] = z & 0xffff;
x[1] = z >> 16;
i = 1;
}
k += 32;
}
while (!x[i])
--i;
b->_wds = i + 1;
#endif
#ifndef Sudden_Underflow
if (de)
{
#endif
#ifdef IBM
*e = (de - Bias - (P - 1) << 2) + k;
*bits = 4 * P + 8 - k - hi0bits (word0 (d) & Frac_mask);
#else
*e = de - Bias - (P - 1) + k;
*bits = P - k;
#endif
#ifndef Sudden_Underflow
}
else
{
*e = de - Bias - (P - 1) + 1 + k;
#ifdef Pack_32
*bits = 32 * i - hi0bits (x[i - 1]);
#else
*bits = (i + 2) * 16 - hi0bits (x[i]);
#endif
}
#endif
return b;
}
#undef d0
#undef d1
double
ratio (_Bigint * a, _Bigint * b)
{
union double_union da, db;
int k, ka, kb;
da.d = b2d (a, &ka);
db.d = b2d (b, &kb);
#ifdef Pack_32
k = ka - kb + 32 * (a->_wds - b->_wds);
#else
k = ka - kb + 16 * (a->_wds - b->_wds);
#endif
#ifdef IBM
if (k > 0)
{
word0 (da) += (k >> 2) * Exp_msk1;
if (k &= 3)
da.d *= 1 << k;
}
else
{
k = -k;
word0 (db) += (k >> 2) * Exp_msk1;
if (k &= 3)
db.d *= 1 << k;
}
#else
if (k > 0)
word0 (da) += k * Exp_msk1;
else
{
k = -k;
word0 (db) += k * Exp_msk1;
}
#endif
return da.d / db.d;
}
const double
tens[] =
{
1e0, 1e1, 1e2, 1e3, 1e4, 1e5, 1e6, 1e7, 1e8, 1e9,
1e10, 1e11, 1e12, 1e13, 1e14, 1e15, 1e16, 1e17, 1e18, 1e19,
1e20, 1e21, 1e22, 1e23, 1e24
};
#if !defined(_DOUBLE_IS_32BITS) && !defined(__v800)
const double bigtens[] =
{1e16, 1e32, 1e64, 1e128, 1e256};
const double tinytens[] =
{1e-16, 1e-32, 1e-64, 1e-128, 1e-256};
#else
const double bigtens[] =
{1e16, 1e32};
const double tinytens[] =
{1e-16, 1e-32};
#endif
double
_mprec_log10 (int dig)
{
double v = 1.0;
if (dig < 24)
return tens[dig];
while (dig > 0)
{
v *= 10;
dig--;
}
return v;
}
void
copybits (__ULong *c,
int n,
_Bigint *b)
{
__ULong *ce, *x, *xe;
#ifdef Pack_16
int nw, nw1;
#endif
ce = c + ((n-1) >> kshift) + 1;
x = b->_x;
#ifdef Pack_32
xe = x + b->_wds;
while(x < xe)
*c++ = *x++;
#else
nw = b->_wds;
nw1 = nw & 1;
for(xe = x + (nw - nw1); x < xe; x += 2)
Storeinc(c, x[1], x[0]);
if (nw1)
*c++ = *x;
#endif
while(c < ce)
*c++ = 0;
}
__ULong
any_on (_Bigint *b,
int k)
{
int n, nwds;
__ULong *x, *x0, x1, x2;
x = b->_x;
nwds = b->_wds;
n = k >> kshift;
if (n > nwds)
n = nwds;
else if (n < nwds && (k &= kmask)) {
x1 = x2 = x[n];
x1 >>= k;
x1 <<= k;
if (x1 != x2)
return 1;
}
x0 = x;
x += n;
while(x > x0)
if (*--x)
return 1;
return 0;
}