26 lines
490 B
C
26 lines
490 B
C
/* TomsFastMath, a fast ISO C bignum library. -- Tom St Denis */
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/* SPDX-License-Identifier: Unlicense */
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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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