#include "tommath_private.h" #ifdef BN_MP_REDUCE_2K_SETUP_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. * * SPDX-License-Identifier: Unlicense */ /* determines the setup value */ int mp_reduce_2k_setup(const mp_int *a, mp_digit *d) { int res, p; mp_int tmp; if ((res = mp_init(&tmp)) != MP_OKAY) { return res; } p = mp_count_bits(a); if ((res = mp_2expt(&tmp, p)) != MP_OKAY) { mp_clear(&tmp); return res; } if ((res = s_mp_sub(&tmp, a, &tmp)) != MP_OKAY) { mp_clear(&tmp); return res; } *d = tmp.dp[0]; mp_clear(&tmp); return MP_OKAY; } #endif /* ref: $Format:%D$ */ /* git commit: $Format:%H$ */ /* commit time: $Format:%ai$ */