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#include <tommath.h>
#ifdef BN_MP_REDUCE_IS_2K_L_C
/* LibTomMath, multiple-precision integer library -- Tom St Denis
*
* LibTomMath is a library that provides multiple-precision
* integer arithmetic as well as number theoretic functionality.
*
* The library was designed directly after the MPI library by
* Michael Fromberger but has been written from scratch with
* additional optimizations in place.
*
* The library is free for all purposes without any express
* guarantee it works.
*
* Tom St Denis, tomstdenis@gmail.com, http://math.libtomcrypt.com
*/
/* determines if reduce_2k_l can be used */
int mp_reduce_is_2k_l(mp_int *a)
{
int ix, iy;
if (a->used == 0) {
return MP_NO;
} else if (a->used == 1) {
return MP_YES;
} else if (a->used > 1) {
/* if more than half of the digits are -1 we're sold */
for (iy = ix = 0; ix < a->used; ix++) {
if (a->dp[ix] == MP_MASK) {
++iy;
}
}
return (iy >= (a->used/2)) ? MP_YES : MP_NO;
}
return MP_NO;
}
#endif
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