18 lines
496 B
C
18 lines
496 B
C
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#include "tommath_private.h"
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#ifdef MP_REDUCE_SETUP_C
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/* LibTomMath, multiple-precision integer library -- Tom St Denis */
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/* SPDX-License-Identifier: Unlicense */
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/* pre-calculate the value required for Barrett reduction
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* For a given modulus "b" it calculates the value required in "a"
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*/
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mp_err mp_reduce_setup(mp_int *a, const mp_int *b)
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{
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mp_err err;
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if ((err = mp_2expt(a, b->used * 2 * MP_DIGIT_BIT)) != MP_OKAY) {
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return err;
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}
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return mp_div(a, b, a, NULL);
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}
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#endif
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