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author | William Joye <wjoye@cfa.harvard.edu> | 2017-10-17 19:50:58 (GMT) |
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committer | William Joye <wjoye@cfa.harvard.edu> | 2017-10-17 19:50:58 (GMT) |
commit | 9b7a6c3507ea3383c60aaecb29f873c9b590ccca (patch) | |
tree | 82ce31ebd8f46803d969034f5aa3db8d7974493c /tcl8.6/libtommath/bn_fast_s_mp_mul_high_digs.c | |
parent | 87fca7325b97005eb44dcf3e198277640af66115 (diff) | |
download | blt-9b7a6c3507ea3383c60aaecb29f873c9b590ccca.zip blt-9b7a6c3507ea3383c60aaecb29f873c9b590ccca.tar.gz blt-9b7a6c3507ea3383c60aaecb29f873c9b590ccca.tar.bz2 |
rm tcl/tk 8.6.7
Diffstat (limited to 'tcl8.6/libtommath/bn_fast_s_mp_mul_high_digs.c')
-rw-r--r-- | tcl8.6/libtommath/bn_fast_s_mp_mul_high_digs.c | 94 |
1 files changed, 0 insertions, 94 deletions
diff --git a/tcl8.6/libtommath/bn_fast_s_mp_mul_high_digs.c b/tcl8.6/libtommath/bn_fast_s_mp_mul_high_digs.c deleted file mode 100644 index ec9f58a..0000000 --- a/tcl8.6/libtommath/bn_fast_s_mp_mul_high_digs.c +++ /dev/null @@ -1,94 +0,0 @@ -#include <tommath.h> -#ifdef BN_FAST_S_MP_MUL_HIGH_DIGS_C -/* LibTomMath, multiple-precision integer library -- Tom St Denis - * - * LibTomMath is a library that provides multiple-precision - * integer arithmetic as well as number theoretic functionality. - * - * The library was designed directly after the MPI library by - * Michael Fromberger but has been written from scratch with - * additional optimizations in place. - * - * The library is free for all purposes without any express - * guarantee it works. - * - * Tom St Denis, tomstdenis@gmail.com, http://math.libtomcrypt.com - */ - -/* this is a modified version of fast_s_mul_digs that only produces - * output digits *above* digs. See the comments for fast_s_mul_digs - * to see how it works. - * - * This is used in the Barrett reduction since for one of the multiplications - * only the higher digits were needed. This essentially halves the work. - * - * Based on Algorithm 14.12 on pp.595 of HAC. - */ -int fast_s_mp_mul_high_digs (mp_int * a, mp_int * b, mp_int * c, int digs) -{ - int olduse, res, pa, ix, iz; - mp_digit W[MP_WARRAY]; - mp_word _W; - - /* grow the destination as required */ - pa = a->used + b->used; - if (c->alloc < pa) { - if ((res = mp_grow (c, pa)) != MP_OKAY) { - return res; - } - } - - /* number of output digits to produce */ - pa = a->used + b->used; - _W = 0; - for (ix = digs; ix < pa; ix++) { - int tx, ty, iy; - mp_digit *tmpx, *tmpy; - - /* get offsets into the two bignums */ - ty = MIN(b->used-1, ix); - tx = ix - ty; - - /* setup temp aliases */ - tmpx = a->dp + tx; - tmpy = b->dp + ty; - - /* this is the number of times the loop will iterrate, essentially its - while (tx++ < a->used && ty-- >= 0) { ... } - */ - iy = MIN(a->used-tx, ty+1); - - /* execute loop */ - for (iz = 0; iz < iy; iz++) { - _W += ((mp_word)*tmpx++)*((mp_word)*tmpy--); - } - - /* store term */ - W[ix] = ((mp_digit)_W) & MP_MASK; - - /* make next carry */ - _W = _W >> ((mp_word)DIGIT_BIT); - } - - /* setup dest */ - olduse = c->used; - c->used = pa; - - { - register mp_digit *tmpc; - - tmpc = c->dp + digs; - for (ix = digs; ix < pa; ix++) { - /* now extract the previous digit [below the carry] */ - *tmpc++ = W[ix]; - } - - /* clear unused digits [that existed in the old copy of c] */ - for (; ix < olduse; ix++) { - *tmpc++ = 0; - } - } - mp_clamp (c); - return MP_OKAY; -} -#endif |