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-rw-r--r--libtommath/bn_s_mp_mul_high_digs.c93
1 files changed, 47 insertions, 46 deletions
diff --git a/libtommath/bn_s_mp_mul_high_digs.c b/libtommath/bn_s_mp_mul_high_digs.c
index f4dca76..e6efd4e 100644
--- a/libtommath/bn_s_mp_mul_high_digs.c
+++ b/libtommath/bn_s_mp_mul_high_digs.c
@@ -1,4 +1,4 @@
-#include <tommath.h>
+#include "tommath_private.h"
#ifdef BN_S_MP_MUL_HIGH_DIGS_C
/* LibTomMath, multiple-precision integer library -- Tom St Denis
*
@@ -11,67 +11,68 @@
*
* The library is free for all purposes without any express
* guarantee it works.
- *
- * Tom St Denis, tomstdenis@gmail.com, http://math.libtomcrypt.com
*/
/* multiplies |a| * |b| and does not compute the lower digs digits
* [meant to get the higher part of the product]
*/
-int
-s_mp_mul_high_digs (mp_int * a, mp_int * b, mp_int * c, int digs)
+int s_mp_mul_high_digs(const mp_int *a, const mp_int *b, mp_int *c, int digs)
{
- mp_int t;
- int res, pa, pb, ix, iy;
- mp_digit u;
- mp_word r;
- mp_digit tmpx, *tmpt, *tmpy;
+ mp_int t;
+ int res, pa, pb, ix, iy;
+ mp_digit u;
+ mp_word r;
+ mp_digit tmpx, *tmpt, *tmpy;
- /* can we use the fast multiplier? */
+ /* can we use the fast multiplier? */
#ifdef BN_FAST_S_MP_MUL_HIGH_DIGS_C
- if (((a->used + b->used + 1) < MP_WARRAY)
- && MIN (a->used, b->used) < (1 << ((CHAR_BIT * sizeof (mp_word)) - (2 * DIGIT_BIT)))) {
- return fast_s_mp_mul_high_digs (a, b, c, digs);
- }
+ if (((a->used + b->used + 1) < (int)MP_WARRAY)
+ && (MIN(a->used, b->used) < (int)(1u << (((size_t)CHAR_BIT * sizeof(mp_word)) - (2u * (size_t)DIGIT_BIT))))) {
+ return fast_s_mp_mul_high_digs(a, b, c, digs);
+ }
#endif
- if ((res = mp_init_size (&t, a->used + b->used + 1)) != MP_OKAY) {
- return res;
- }
- t.used = a->used + b->used + 1;
+ if ((res = mp_init_size(&t, a->used + b->used + 1)) != MP_OKAY) {
+ return res;
+ }
+ t.used = a->used + b->used + 1;
- pa = a->used;
- pb = b->used;
- for (ix = 0; ix < pa; ix++) {
- /* clear the carry */
- u = 0;
+ pa = a->used;
+ pb = b->used;
+ for (ix = 0; ix < pa; ix++) {
+ /* clear the carry */
+ u = 0;
- /* left hand side of A[ix] * B[iy] */
- tmpx = a->dp[ix];
+ /* left hand side of A[ix] * B[iy] */
+ tmpx = a->dp[ix];
- /* alias to the address of where the digits will be stored */
- tmpt = &(t.dp[digs]);
+ /* alias to the address of where the digits will be stored */
+ tmpt = &(t.dp[digs]);
- /* alias for where to read the right hand side from */
- tmpy = b->dp + (digs - ix);
+ /* alias for where to read the right hand side from */
+ tmpy = b->dp + (digs - ix);
- for (iy = digs - ix; iy < pb; iy++) {
- /* calculate the double precision result */
- r = ((mp_word)*tmpt) +
- ((mp_word)tmpx) * ((mp_word)*tmpy++) +
- ((mp_word) u);
+ for (iy = digs - ix; iy < pb; iy++) {
+ /* calculate the double precision result */
+ r = (mp_word)*tmpt +
+ ((mp_word)tmpx * (mp_word)*tmpy++) +
+ (mp_word)u;
- /* get the lower part */
- *tmpt++ = (mp_digit) (r & ((mp_word) MP_MASK));
+ /* get the lower part */
+ *tmpt++ = (mp_digit)(r & (mp_word)MP_MASK);
- /* carry the carry */
- u = (mp_digit) (r >> ((mp_word) DIGIT_BIT));
- }
- *tmpt = u;
- }
- mp_clamp (&t);
- mp_exch (&t, c);
- mp_clear (&t);
- return MP_OKAY;
+ /* carry the carry */
+ u = (mp_digit)(r >> (mp_word)DIGIT_BIT);
+ }
+ *tmpt = u;
+ }
+ mp_clamp(&t);
+ mp_exch(&t, c);
+ mp_clear(&t);
+ return MP_OKAY;
}
#endif
+
+/* ref: $Format:%D$ */
+/* git commit: $Format:%H$ */
+/* commit time: $Format:%ai$ */