diff options
author | das <das@FreeBSD.org> | 2003-03-12 20:18:32 +0000 |
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committer | das <das@FreeBSD.org> | 2003-03-12 20:18:32 +0000 |
commit | db3a0f1435efcb4461005cb8d8509bff01f9b018 (patch) | |
tree | 632bc138392cfc4c37a7e12065afe443d31145eb /contrib/gdtoa/sum.c | |
download | FreeBSD-src-db3a0f1435efcb4461005cb8d8509bff01f9b018.zip FreeBSD-src-db3a0f1435efcb4461005cb8d8509bff01f9b018.tar.gz |
Initial import of David Gay's gdtoa library for conversion between
strings and floating point.
Diffstat (limited to 'contrib/gdtoa/sum.c')
-rw-r--r-- | contrib/gdtoa/sum.c | 104 |
1 files changed, 104 insertions, 0 deletions
diff --git a/contrib/gdtoa/sum.c b/contrib/gdtoa/sum.c new file mode 100644 index 0000000..1e1a4de --- /dev/null +++ b/contrib/gdtoa/sum.c @@ -0,0 +1,104 @@ +/**************************************************************** + +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 + Bell Laboratories, Room 2C-463 + 600 Mountain Avenue + Murray Hill, NJ 07974-0636 + U.S.A. + dmg@bell-labs.com + */ + +#include "gdtoaimp.h" + + Bigint * +#ifdef KR_headers +sum(a, b) Bigint *a; Bigint *b; +#else +sum(Bigint *a, Bigint *b) +#endif +{ + 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; + } |