42 lines
1.1 KiB
C
42 lines
1.1 KiB
C
/* LibTomMath, multiple-precision integer library -- Tom St Denis
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*
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* LibTomMath is a library that provides multiple-precision
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* integer arithmetic as well as number theoretic functionality.
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*
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* The library was designed directly after the MPI library by
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* Michael Fromberger but has been written from scratch with
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* additional optimizations in place.
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*
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* The library is free for all purposes without any express
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* guarantee it works.
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*
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* Tom St Denis, tomstdenis@iahu.ca, http://math.libtomcrypt.org
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*/
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#include <tommath.h>
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/* computes b = a*a */
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int
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mp_sqr (mp_int * a, mp_int * b)
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{
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int res;
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/* use Toom-Cook? */
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if (a->used >= TOOM_SQR_CUTOFF) {
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res = mp_toom_sqr(a, b);
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/* Karatsuba? */
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} else if (a->used >= KARATSUBA_SQR_CUTOFF) {
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res = mp_karatsuba_sqr (a, b);
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} else {
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/* can we use the fast comba multiplier? */
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if ((a->used * 2 + 1) < MP_WARRAY &&
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a->used <
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(1 << (sizeof(mp_word) * CHAR_BIT - 2*DIGIT_BIT - 1))) {
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res = fast_s_mp_sqr (a, b);
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} else {
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res = s_mp_sqr (a, b);
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}
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}
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b->sign = MP_ZPOS;
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return res;
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}
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