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#include "tommath_private.h"
#ifdef BN_MP_REDUCE_IS_2K_C
/* LibTomMath, multiple-precision integer library -- Tom St Denis */
/* SPDX-License-Identifier: Unlicense */
/* determines if mp_reduce_2k can be used */
mp_bool mp_reduce_is_2k(const mp_int *a)
{
int ix, iy, iw;
mp_digit iz;
if (a->used == 0) {
return MP_NO;
} else if (a->used == 1) {
return MP_YES;
} else if (a->used > 1) {
iy = mp_count_bits(a);
iz = 1;
iw = 1;
/* Test every bit from the second digit up, must be 1 */
for (ix = MP_DIGIT_BIT; ix < iy; ix++) {
if ((a->dp[iw] & iz) == 0u) {
return MP_NO;
}
iz <<= 1;
if (iz > MP_DIGIT_MAX) {
++iw;
iz = 1;
}
}
return MP_YES;
} else {
return MP_YES;
}
}
#endif
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