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comparison bn_fast_s_mp_mul_high_digs.c @ 386:97db060d0ef5 libtommath-orig libtommath-0.40

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Update to LibTomMath 0.40
author Matt Johnston <matt@ucc.asn.au>
date Thu, 11 Jan 2007 03:11:15 +0000
parents 91fbc376f010
children
comparison
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282:91fbc376f010 386:97db060d0ef5
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.org 15 * Tom St Denis, [email protected], http://math.libtomcrypt.com
16 */ 16 */
17 17
18 /* this is a modified version of fast_s_mul_digs that only produces 18 /* this is a modified version of fast_s_mul_digs that only produces
19 * output digits *above* digs. See the comments for fast_s_mul_digs 19 * output digits *above* digs. See the comments for fast_s_mul_digs
20 * to see how it works. 20 * to see how it works.
68 68
69 /* make next carry */ 69 /* make next carry */
70 _W = _W >> ((mp_word)DIGIT_BIT); 70 _W = _W >> ((mp_word)DIGIT_BIT);
71 } 71 }
72 72
73 /* store final carry */
74 W[ix] = (mp_digit)(_W & MP_MASK);
75
76 /* setup dest */ 73 /* setup dest */
77 olduse = c->used; 74 olduse = c->used;
78 c->used = pa; 75 c->used = pa;
79 76
80 { 77 {
81 register mp_digit *tmpc; 78 register mp_digit *tmpc;
82 79
83 tmpc = c->dp + digs; 80 tmpc = c->dp + digs;
84 for (ix = digs; ix <= pa; ix++) { 81 for (ix = digs; ix < pa; ix++) {
85 /* now extract the previous digit [below the carry] */ 82 /* now extract the previous digit [below the carry] */
86 *tmpc++ = W[ix]; 83 *tmpc++ = W[ix];
87 } 84 }
88 85
89 /* clear unused digits [that existed in the old copy of c] */ 86 /* clear unused digits [that existed in the old copy of c] */
93 } 90 }
94 mp_clamp (c); 91 mp_clamp (c);
95 return MP_OKAY; 92 return MP_OKAY;
96 } 93 }
97 #endif 94 #endif
95
96 /* $Source: /cvs/libtom/libtommath/bn_fast_s_mp_mul_high_digs.c,v $ */
97 /* $Revision: 1.5 $ */
98 /* $Date: 2006/11/14 03:46:25 $ */