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comparison libtommath/bn_mp_cnt_lsb.c @ 1436:60fc6476e044

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Update to libtommath v1.0
author Matt Johnston <matt@ucc.asn.au>
date Sat, 24 Jun 2017 22:37:14 +0800
parents 5ff8218bcee9
children 8bba51a55704
comparison
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1435:f849a5ca2efc 1436:60fc6476e044
1 #include <tommath.h> 1 #include <tommath_private.h>
2 #ifdef BN_MP_CNT_LSB_C 2 #ifdef BN_MP_CNT_LSB_C
3 /* LibTomMath, multiple-precision integer library -- Tom St Denis 3 /* LibTomMath, multiple-precision integer library -- Tom St Denis
4 * 4 *
5 * LibTomMath is a library that provides multiple-precision 5 * LibTomMath is a library that provides multiple-precision
6 * integer arithmetic as well as number theoretic functionality. 6 * integer arithmetic as well as number theoretic functionality.
10 * additional optimizations in place. 10 * additional optimizations in place.
11 * 11 *
12 * The library is free for all purposes without any express 12 * The library is free for all purposes without any express
13 * guarantee it works. 13 * guarantee it works.
14 * 14 *
15 * Tom St Denis, [email protected], http://math.libtomcrypt.com 15 * Tom St Denis, [email protected], http://libtom.org
16 */ 16 */
17 17
18 static const int lnz[16] = { 18 static const int lnz[16] = {
19 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0 19 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0
20 }; 20 };
24 { 24 {
25 int x; 25 int x;
26 mp_digit q, qq; 26 mp_digit q, qq;
27 27
28 /* easy out */ 28 /* easy out */
29 if (mp_iszero(a) == 1) { 29 if (mp_iszero(a) == MP_YES) {
30 return 0; 30 return 0;
31 } 31 }
32 32
33 /* scan lower digits until non-zero */ 33 /* scan lower digits until non-zero */
34 for (x = 0; x < a->used && a->dp[x] == 0; x++); 34 for (x = 0; (x < a->used) && (a->dp[x] == 0); x++) {}
35 q = a->dp[x]; 35 q = a->dp[x];
36 x *= DIGIT_BIT; 36 x *= DIGIT_BIT;
37 37
38 /* now scan this digit until a 1 is found */ 38 /* now scan this digit until a 1 is found */
39 if ((q & 1) == 0) { 39 if ((q & 1) == 0) {
46 return x; 46 return x;
47 } 47 }
48 48
49 #endif 49 #endif
50 50
51 /* $Source: /cvs/libtom/libtommath/bn_mp_cnt_lsb.c,v $ */ 51 /* $Source$ */
52 /* $Revision: 1.3 $ */ 52 /* $Revision$ */
53 /* $Date: 2006/03/31 14:18:44 $ */ 53 /* $Date$ */