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comparison libtommath/bn_mp_gcd.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_GCD_C 2 #ifdef BN_MP_GCD_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 /* Greatest Common Divisor using the binary method */ 18 /* Greatest Common Divisor using the binary method */
19 int mp_gcd (mp_int * a, mp_int * b, mp_int * c) 19 int mp_gcd (mp_int * a, mp_int * b, mp_int * c)
20 { 20 {
68 if ((res = mp_div_2d(&v, v_lsb - k, &v, NULL)) != MP_OKAY) { 68 if ((res = mp_div_2d(&v, v_lsb - k, &v, NULL)) != MP_OKAY) {
69 goto LBL_V; 69 goto LBL_V;
70 } 70 }
71 } 71 }
72 72
73 while (mp_iszero(&v) == 0) { 73 while (mp_iszero(&v) == MP_NO) {
74 /* make sure v is the largest */ 74 /* make sure v is the largest */
75 if (mp_cmp_mag(&u, &v) == MP_GT) { 75 if (mp_cmp_mag(&u, &v) == MP_GT) {
76 /* swap u and v to make sure v is >= u */ 76 /* swap u and v to make sure v is >= u */
77 mp_exch(&u, &v); 77 mp_exch(&u, &v);
78 } 78 }
98 LBL_U:mp_clear (&v); 98 LBL_U:mp_clear (&v);
99 return res; 99 return res;
100 } 100 }
101 #endif 101 #endif
102 102
103 /* $Source: /cvs/libtom/libtommath/bn_mp_gcd.c,v $ */ 103 /* $Source$ */
104 /* $Revision: 1.4 $ */ 104 /* $Revision$ */
105 /* $Date: 2006/03/31 14:18:44 $ */ 105 /* $Date$ */