1 /* TomsFastMath, a fast ISO C bignum library. 2 * 3 * This project is meant to fill in where LibTomMath 4 * falls short. That is speed ;-) 5 * 6 * This project is public domain and free for all purposes. 7 * 8 * Tom St Denis, tomstdenis@gmail.com 9 */ 10 #include "bignum_fast.h" 11 12 /* c = a * b */ fp_mul_d(fp_int * a,fp_digit b,fp_int * c)13void fp_mul_d(fp_int *a, fp_digit b, fp_int *c) 14 { 15 fp_word w; 16 int x, oldused; 17 18 oldused = c->used; 19 c->used = a->used; 20 c->sign = a->sign; 21 w = 0; 22 for (x = 0; x < a->used; x++) { 23 w = ((fp_word)a->dp[x]) * ((fp_word)b) + w; 24 c->dp[x] = (fp_digit)w; 25 w = w >> DIGIT_BIT; 26 } 27 if (w != 0 && (a->used != FP_SIZE)) { 28 c->dp[c->used++] = w; 29 ++x; 30 } 31 for (; x < oldused; x++) { 32 c->dp[x] = 0; 33 } 34 fp_clamp(c); 35 } 36 37 38 /* $Source: /cvs/libtom/tomsfastmath/src/mul/fp_mul_d.c,v $ */ 39 /* $Revision: 1.1 $ */ 40 /* $Date: 2006/12/31 21:25:53 $ */ 41