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-rw-r--r--libtommath/bn_fast_s_mp_sqr.c114
1 files changed, 0 insertions, 114 deletions
diff --git a/libtommath/bn_fast_s_mp_sqr.c b/libtommath/bn_fast_s_mp_sqr.c
deleted file mode 100644
index f435af9..0000000
--- a/libtommath/bn_fast_s_mp_sqr.c
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@@ -1,114 +0,0 @@
-#include <tommath_private.h>
-#ifdef BN_FAST_S_MP_SQR_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
- */
-
-/* the jist of squaring...
- * you do like mult except the offset of the tmpx [one that
- * starts closer to zero] can't equal the offset of tmpy.
- * So basically you set up iy like before then you min it with
- * (ty-tx) so that it never happens. You double all those
- * you add in the inner loop
-
-After that loop you do the squares and add them in.
-*/
-
-int fast_s_mp_sqr (mp_int * a, mp_int * b)
-{
- int olduse, res, pa, ix, iz;
- mp_digit W[MP_WARRAY], *tmpx;
- mp_word W1;
-
- /* grow the destination as required */
- pa = a->used + a->used;
- if (b->alloc < pa) {
- if ((res = mp_grow (b, pa)) != MP_OKAY) {
- return res;
- }
- }
-
- /* number of output digits to produce */
- W1 = 0;
- for (ix = 0; ix < pa; ix++) {
- int tx, ty, iy;
- mp_word _W;
- mp_digit *tmpy;
-
- /* clear counter */
- _W = 0;
-
- /* get offsets into the two bignums */
- ty = MIN(a->used-1, ix);
- tx = ix - ty;
-
- /* setup temp aliases */
- tmpx = a->dp + tx;
- tmpy = a->dp + ty;
-
- /* this is the number of times the loop will iterrate, essentially
- while (tx++ < a->used && ty-- >= 0) { ... }
- */
- iy = MIN(a->used-tx, ty+1);
-
- /* now for squaring tx can never equal ty
- * we halve the distance since they approach at a rate of 2x
- * and we have to round because odd cases need to be executed
- */
- iy = MIN(iy, ((ty-tx)+1)>>1);
-
- /* execute loop */
- for (iz = 0; iz < iy; iz++) {
- _W += ((mp_word)*tmpx++)*((mp_word)*tmpy--);
- }
-
- /* double the inner product and add carry */
- _W = _W + _W + W1;
-
- /* even columns have the square term in them */
- if ((ix&1) == 0) {
- _W += ((mp_word)a->dp[ix>>1])*((mp_word)a->dp[ix>>1]);
- }
-
- /* store it */
- W[ix] = (mp_digit)(_W & MP_MASK);
-
- /* make next carry */
- W1 = _W >> ((mp_word)DIGIT_BIT);
- }
-
- /* setup dest */
- olduse = b->used;
- b->used = a->used+a->used;
-
- {
- mp_digit *tmpb;
- tmpb = b->dp;
- for (ix = 0; ix < pa; ix++) {
- *tmpb++ = W[ix] & MP_MASK;
- }
-
- /* clear unused digits [that existed in the old copy of c] */
- for (; ix < olduse; ix++) {
- *tmpb++ = 0;
- }
- }
- mp_clamp (b);
- return MP_OKAY;
-}
-#endif
-
-/* ref: $Format:%D$ */
-/* git commit: $Format:%H$ */
-/* commit time: $Format:%ai$ */