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#include "tommath_private.h"
#ifdef BN_MP_COUNT_BITS_C
/* LibTomMath, multiple-precision integer library -- Tom St Denis */
/* SPDX-License-Identifier: Unlicense */
/* returns the number of bits in an int */
int mp_count_bits(const mp_int *a)
{
int r;
mp_digit q;
/* shortcut */
if (MP_IS_ZERO(a)) {
return 0;
}
/* get number of digits and add that */
r = (a->used - 1) * MP_DIGIT_BIT;
/* take the last digit and count the bits in it */
q = a->dp[a->used - 1];
while (q > 0u) {
++r;
q >>= 1u;
}
return r;
}
#endif
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