comparison bn_mp_2expt.c @ 142:d29b64170cf0 libtommath-orig

import of libtommath 0.32
author Matt Johnston <matt@ucc.asn.au>
date Sun, 19 Dec 2004 11:33:56 +0000
parents 86e0b50a9b58
children
comparison
equal deleted inserted replaced
19:e1037a1e12e7 142:d29b64170cf0
1 #include <tommath.h>
2 #ifdef BN_MP_2EXPT_C
1 /* LibTomMath, multiple-precision integer library -- Tom St Denis 3 /* LibTomMath, multiple-precision integer library -- Tom St Denis
2 * 4 *
3 * LibTomMath is a library that provides multiple-precision 5 * LibTomMath is a library that provides multiple-precision
4 * integer arithmetic as well as number theoretic functionality. 6 * integer arithmetic as well as number theoretic functionality.
5 * 7 *
10 * The library is free for all purposes without any express 12 * The library is free for all purposes without any express
11 * guarantee it works. 13 * guarantee it works.
12 * 14 *
13 * Tom St Denis, [email protected], http://math.libtomcrypt.org 15 * Tom St Denis, [email protected], http://math.libtomcrypt.org
14 */ 16 */
15 #include <tommath.h>
16 17
17 /* computes a = 2**b 18 /* computes a = 2**b
18 * 19 *
19 * Simple algorithm which zeroes the int, grows it then just sets one bit 20 * Simple algorithm which zeroes the int, grows it then just sets one bit
20 * as required. 21 * as required.
34 35
35 /* set the used count of where the bit will go */ 36 /* set the used count of where the bit will go */
36 a->used = b / DIGIT_BIT + 1; 37 a->used = b / DIGIT_BIT + 1;
37 38
38 /* put the single bit in its place */ 39 /* put the single bit in its place */
39 a->dp[b / DIGIT_BIT] = 1 << (b % DIGIT_BIT); 40 a->dp[b / DIGIT_BIT] = ((mp_digit)1) << (b % DIGIT_BIT);
40 41
41 return MP_OKAY; 42 return MP_OKAY;
42 } 43 }
44 #endif