37 lines
677 B
C
37 lines
677 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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int fp_count_bits (fp_int * a)
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{
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int r;
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fp_digit q;
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/* shortcut */
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if (a->used == 0) {
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return 0;
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}
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/* get number of digits and add that */
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r = (a->used - 1) * DIGIT_BIT;
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/* take the last digit and count the bits in it */
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q = a->dp[a->used - 1];
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while (q > ((fp_digit) 0)) {
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++r;
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q >>= ((fp_digit) 1);
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}
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return r;
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}
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/* $Source$ */
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/* $Revision$ */
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/* $Date$ */
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