newlib/winsup/mingw/mingwex/gdtoa/sum.c
Chris Sutcliffe 15e114f5c5 2009-06-28 Ozkan Sezer <sezero@users.sourceforge.net>
* mingwex/gdtoa/README.mingw mingwex/gdtoa/gdtoa_fltrnds.h: New files.
        * mingwex/gdtoa/README mingwex/gdtoa/dmisc.c mingwex/gdtoa/dtoa.c
        mingwex/gdtoa/g__fmt.c mingwex/gdtoa/g_dfmt.c mingwex/gdtoa/g_ffmt.c
        mingwex/gdtoa/g_xfmt.c mingwex/gdtoa/gd_arith.h mingwex/gdtoa/gd_qnan.h
        mingwex/gdtoa/gdtoa.c mingwex/gdtoa/gdtoa.h mingwex/gdtoa/gdtoaimp.h
        mingwex/gdtoa/gethex.c mingwex/gdtoa/gmisc.c mingwex/gdtoa/hd_init.c
        mingwex/gdtoa/hexnan.c mingwex/gdtoa/misc.c mingwex/gdtoa/qnan.c
        mingwex/gdtoa/smisc.c mingwex/gdtoa/strtodg.c mingwex/gdtoa/strtodnrp.c
        mingwex/gdtoa/strtof.c mingwex/gdtoa/strtopx.c mingwex/gdtoa/sum.c
        mingwex/gdtoa/ulp.c:  Update the gdtoa library to match the netlib.org
        sources as of Apr. 20, 2009.  Update further to match the sources in
        the mingw-w64 tree as of June 28, 2009, by removing IBM, CRAY and VAX
        code, removing KR_headers, ANSI, Void and Char ifdefs, renaming the
        double/ulong union from U to dbl_union for better grepping and white-
        space tidy-ups.
2009-07-12 22:44:37 +00:00

92 lines
2.4 KiB
C
Executable File

/****************************************************************
The author of this software is David M. Gay.
Copyright (C) 1998 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 "."). */
#include "gdtoaimp.h"
Bigint *sum (Bigint *a, Bigint *b)
{
Bigint *c;
ULong carry, *xc, *xa, *xb, *xe, y;
#ifdef Pack_32
ULong z;
#endif
if (a->wds < b->wds) {
c = b; b = a; a = c;
}
c = Balloc(a->k);
c->wds = a->wds;
carry = 0;
xa = a->x;
xb = b->x;
xc = c->x;
xe = xc + b->wds;
#ifdef Pack_32
do {
y = (*xa & 0xffff) + (*xb & 0xffff) + carry;
carry = (y & 0x10000) >> 16;
z = (*xa++ >> 16) + (*xb++ >> 16) + carry;
carry = (z & 0x10000) >> 16;
Storeinc(xc, z, y);
} while(xc < xe);
xe += a->wds - b->wds;
while(xc < xe) {
y = (*xa & 0xffff) + carry;
carry = (y & 0x10000) >> 16;
z = (*xa++ >> 16) + carry;
carry = (z & 0x10000) >> 16;
Storeinc(xc, z, y);
}
#else
do {
y = *xa++ + *xb++ + carry;
carry = (y & 0x10000) >> 16;
*xc++ = y & 0xffff;
} while(xc < xe);
xe += a->wds - b->wds;
while(xc < xe) {
y = *xa++ + carry;
carry = (y & 0x10000) >> 16;
*xc++ = y & 0xffff;
}
#endif
if (carry) {
if (c->wds == c->maxwds) {
b = Balloc(c->k + 1);
Bcopy(b, c);
Bfree(c);
c = b;
}
c->x[c->wds++] = 1;
}
return c;
}