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-rw-r--r--libtommath/bn_fast_s_mp_mul_high_digs.c98
1 files changed, 0 insertions, 98 deletions
diff --git a/libtommath/bn_fast_s_mp_mul_high_digs.c b/libtommath/bn_fast_s_mp_mul_high_digs.c
deleted file mode 100644
index 08f0355..0000000
--- a/libtommath/bn_fast_s_mp_mul_high_digs.c
+++ /dev/null
@@ -1,98 +0,0 @@
-#include <tommath_private.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, tstdenis82@gmail.com, http://libtom.org
- */
-
-/* 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;
-
- {
- 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
-
-/* ref: $Format:%D$ */
-/* git commit: $Format:%H$ */
-/* commit time: $Format:%ai$ */