44 lines
1018 B
C
44 lines
1018 B
C
/* TomsFastMath, a fast ISO C bignum library.
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*
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* This project is meant to fill in where LibTomMath
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* falls short. That is speed ;-)
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*
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* This project is public domain and free for all purposes.
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*
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* Tom St Denis, tomstdenis@gmail.com
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*/
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#include <tfm_private.h>
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void fp_add(fp_int *a, fp_int *b, fp_int *c)
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{
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int sa, sb;
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/* get sign of both inputs */
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sa = a->sign;
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sb = b->sign;
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/* handle two cases, not four */
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if (sa == sb) {
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/* both positive or both negative */
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/* add their magnitudes, copy the sign */
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c->sign = sa;
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s_fp_add (a, b, c);
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} else {
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/* one positive, the other negative */
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/* subtract the one with the greater magnitude from */
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/* the one of the lesser magnitude. The result gets */
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/* the sign of the one with the greater magnitude. */
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if (fp_cmp_mag (a, b) == FP_LT) {
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c->sign = sb;
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s_fp_sub (b, a, c);
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} else {
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c->sign = sa;
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s_fp_sub (a, b, c);
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}
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}
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}
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/* $Source$ */
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/* $Revision$ */
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/* $Date$ */
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