40 lines
785 B
C
40 lines
785 B
C
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/* TomsFastMath, a fast ISO C bignum library.
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*
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* This project is meant to fill in where LibTomMath
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* falls short. That is speed ;-)
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*
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* This project is public domain and free for all purposes.
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*
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* Tom St Denis, tomstdenis@gmail.com
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*/
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#include "bignum_fast.h"
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/* computes a = 2**b */
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void fp_2expt(fp_int *a, int b)
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{
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int z;
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/* zero a as per default */
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fp_zero (a);
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if (b < 0) {
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return;
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}
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z = b / DIGIT_BIT;
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if (z >= FP_SIZE) {
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return;
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}
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/* set the used count of where the bit will go */
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a->used = z + 1;
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/* put the single bit in its place */
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a->dp[z] = ((fp_digit)1) << (b % DIGIT_BIT);
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}
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/* $Source: /cvs/libtom/tomsfastmath/src/exptmod/fp_2expt.c,v $ */
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/* $Revision: 1.1 $ */
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/* $Date: 2006/12/31 21:25:53 $ */
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