41 lines
908 B
C
41 lines
908 B
C
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/* 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 "bignum_fast.h"
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/* c = a * b */
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void fp_mul_d(fp_int *a, fp_digit b, fp_int *c)
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{
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fp_word w;
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int x, oldused;
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oldused = c->used;
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c->used = a->used;
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c->sign = a->sign;
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w = 0;
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for (x = 0; x < a->used; x++) {
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w = ((fp_word)a->dp[x]) * ((fp_word)b) + w;
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c->dp[x] = (fp_digit)w;
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w = w >> DIGIT_BIT;
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}
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if (w != 0 && (a->used != FP_SIZE)) {
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c->dp[c->used++] = w;
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++x;
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}
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for (; x < oldused; x++) {
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c->dp[x] = 0;
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}
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fp_clamp(c);
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}
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/* $Source: /cvs/libtom/tomsfastmath/src/mul/fp_mul_d.c,v $ */
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/* $Revision: 1.1 $ */
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/* $Date: 2006/12/31 21:25:53 $ */
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