clamav/libclamav/tomsfastmath/addsub/fp_add.c
Micah Snyder 375ecf678c Update vendored TomsFastMath code to 0.13.1
Update the vendored TomsFastMath (TFM) library to v0.13.1.

Resolves: https://bugzilla.clamav.net/show_bug.cgi?id=11992

I removed compatibility macro's from when libTomMath was used.
This required removing a bunch of faux-error handling because
the fast-math equivalent functions return void, and cannot fail.

The previous version used had named the header "bignum_fast.h"
instead of "tfm.h" and had customizations in that header to enable
TFM_CHECK all the time, and also TFM_NO_ASM if __GNUC__ not defined
or if the system isn't 64bit architecture. This update uses tfm.h
as-is, and has CMake define TFM_CHECK and TFM_NO_ASM as needed.

I've kept bignum.h as an interface to including tfm.h so that in
the future we can more easily add support for system-installed
TomsFastMath instead of the vendored one, taking inspiration from
Debian's patch to support system-TomsFastMath.

See: https://salsa.debian.org/clamav-team/clamav/-/blob/unstable/debian/patches/add-support-for-system-tomsfastmath.patch
2022-02-10 12:54:23 -07:00

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1,018 B
C

/* TomsFastMath, a fast ISO C bignum library.
*
* This project is meant to fill in where LibTomMath
* falls short. That is speed ;-)
*
* This project is public domain and free for all purposes.
*
* Tom St Denis, tomstdenis@gmail.com
*/
#include <tfm_private.h>
void fp_add(fp_int *a, fp_int *b, fp_int *c)
{
int sa, sb;
/* get sign of both inputs */
sa = a->sign;
sb = b->sign;
/* handle two cases, not four */
if (sa == sb) {
/* both positive or both negative */
/* add their magnitudes, copy the sign */
c->sign = sa;
s_fp_add (a, b, c);
} else {
/* one positive, the other negative */
/* subtract the one with the greater magnitude from */
/* the one of the lesser magnitude. The result gets */
/* the sign of the one with the greater magnitude. */
if (fp_cmp_mag (a, b) == FP_LT) {
c->sign = sb;
s_fp_sub (b, a, c);
} else {
c->sign = sa;
s_fp_sub (a, b, c);
}
}
}
/* $Source$ */
/* $Revision$ */
/* $Date$ */