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annotate bn_mp_dr_setup.c @ 2:86e0b50a9b58 libtommath-orig ltm-0.30-orig

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ltm 0.30 orig import
author Matt Johnston <matt@ucc.asn.au>
date Mon, 31 May 2004 18:25:22 +0000
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children d29b64170cf0
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1 /* LibTomMath, multiple-precision integer library -- Tom St Denis
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2 *
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3 * LibTomMath is a library that provides multiple-precision
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4 * integer arithmetic as well as number theoretic functionality.
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5 *
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6 * The library was designed directly after the MPI library by
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7 * Michael Fromberger but has been written from scratch with
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8 * additional optimizations in place.
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9 *
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10 * The library is free for all purposes without any express
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11 * guarantee it works.
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12 *
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13 * Tom St Denis, [email protected], http://math.libtomcrypt.org
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14 */
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15 #include <tommath.h>
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16
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17 /* determines the setup value */
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18 void mp_dr_setup(mp_int *a, mp_digit *d)
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19 {
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20 /* the casts are required if DIGIT_BIT is one less than
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21 * the number of bits in a mp_digit [e.g. DIGIT_BIT==31]
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22 */
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23 *d = (mp_digit)((((mp_word)1) << ((mp_word)DIGIT_BIT)) -
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24 ((mp_word)a->dp[0]));
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25 }
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