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-rw-r--r--libtommath/bn_mp_toom_mul.c278
1 files changed, 140 insertions, 138 deletions
diff --git a/libtommath/bn_mp_toom_mul.c b/libtommath/bn_mp_toom_mul.c
index fa29078..4731f8f 100644
--- a/libtommath/bn_mp_toom_mul.c
+++ b/libtommath/bn_mp_toom_mul.c
@@ -1,4 +1,4 @@
-#include <tommath.h>
+#include <tommath_private.h>
#ifdef BN_MP_TOOM_MUL_C
/* LibTomMath, multiple-precision integer library -- Tom St Denis
*
@@ -12,31 +12,31 @@
* The library is free for all purposes without any express
* guarantee it works.
*
- * Tom St Denis, tomstdenis@gmail.com, http://math.libtomcrypt.com
+ * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
*/
-/* multiplication using the Toom-Cook 3-way algorithm
+/* multiplication using the Toom-Cook 3-way algorithm
*
- * Much more complicated than Karatsuba but has a lower
- * asymptotic running time of O(N**1.464). This algorithm is
- * only particularly useful on VERY large inputs
+ * Much more complicated than Karatsuba but has a lower
+ * asymptotic running time of O(N**1.464). This algorithm is
+ * only particularly useful on VERY large inputs
* (we're talking 1000s of digits here...).
*/
int mp_toom_mul(mp_int *a, mp_int *b, mp_int *c)
{
mp_int w0, w1, w2, w3, w4, tmp1, tmp2, a0, a1, a2, b0, b1, b2;
int res, B;
-
+
/* init temps */
- if ((res = mp_init_multi(&w0, &w1, &w2, &w3, &w4,
- &a0, &a1, &a2, &b0, &b1,
+ if ((res = mp_init_multi(&w0, &w1, &w2, &w3, &w4,
+ &a0, &a1, &a2, &b0, &b1,
&b2, &tmp1, &tmp2, NULL)) != MP_OKAY) {
return res;
}
-
+
/* B */
B = MIN(a->used, b->used) / 3;
-
+
/* a = a2 * B**2 + a1 * B + a0 */
if ((res = mp_mod_2d(a, DIGIT_BIT * B, &a0)) != MP_OKAY) {
goto ERR;
@@ -46,13 +46,15 @@ int mp_toom_mul(mp_int *a, mp_int *b, mp_int *c)
goto ERR;
}
mp_rshd(&a1, B);
- mp_mod_2d(&a1, DIGIT_BIT * B, &a1);
+ if ((res = mp_mod_2d(&a1, DIGIT_BIT * B, &a1)) != MP_OKAY) {
+ goto ERR;
+ }
if ((res = mp_copy(a, &a2)) != MP_OKAY) {
goto ERR;
}
mp_rshd(&a2, B*2);
-
+
/* b = b2 * B**2 + b1 * B + b0 */
if ((res = mp_mod_2d(b, DIGIT_BIT * B, &b0)) != MP_OKAY) {
goto ERR;
@@ -62,23 +64,23 @@ int mp_toom_mul(mp_int *a, mp_int *b, mp_int *c)
goto ERR;
}
mp_rshd(&b1, B);
- mp_mod_2d(&b1, DIGIT_BIT * B, &b1);
+ (void)mp_mod_2d(&b1, DIGIT_BIT * B, &b1);
if ((res = mp_copy(b, &b2)) != MP_OKAY) {
goto ERR;
}
mp_rshd(&b2, B*2);
-
+
/* w0 = a0*b0 */
if ((res = mp_mul(&a0, &b0, &w0)) != MP_OKAY) {
goto ERR;
}
-
+
/* w4 = a2 * b2 */
if ((res = mp_mul(&a2, &b2, &w4)) != MP_OKAY) {
goto ERR;
}
-
+
/* w1 = (a2 + 2(a1 + 2a0))(b2 + 2(b1 + 2b0)) */
if ((res = mp_mul_2(&a0, &tmp1)) != MP_OKAY) {
goto ERR;
@@ -92,7 +94,7 @@ int mp_toom_mul(mp_int *a, mp_int *b, mp_int *c)
if ((res = mp_add(&tmp1, &a2, &tmp1)) != MP_OKAY) {
goto ERR;
}
-
+
if ((res = mp_mul_2(&b0, &tmp2)) != MP_OKAY) {
goto ERR;
}
@@ -105,11 +107,11 @@ int mp_toom_mul(mp_int *a, mp_int *b, mp_int *c)
if ((res = mp_add(&tmp2, &b2, &tmp2)) != MP_OKAY) {
goto ERR;
}
-
+
if ((res = mp_mul(&tmp1, &tmp2, &w1)) != MP_OKAY) {
goto ERR;
}
-
+
/* w3 = (a0 + 2(a1 + 2a2))(b0 + 2(b1 + 2b2)) */
if ((res = mp_mul_2(&a2, &tmp1)) != MP_OKAY) {
goto ERR;
@@ -123,7 +125,7 @@ int mp_toom_mul(mp_int *a, mp_int *b, mp_int *c)
if ((res = mp_add(&tmp1, &a0, &tmp1)) != MP_OKAY) {
goto ERR;
}
-
+
if ((res = mp_mul_2(&b2, &tmp2)) != MP_OKAY) {
goto ERR;
}
@@ -136,11 +138,11 @@ int mp_toom_mul(mp_int *a, mp_int *b, mp_int *c)
if ((res = mp_add(&tmp2, &b0, &tmp2)) != MP_OKAY) {
goto ERR;
}
-
+
if ((res = mp_mul(&tmp1, &tmp2, &w3)) != MP_OKAY) {
goto ERR;
}
-
+
/* w2 = (a2 + a1 + a0)(b2 + b1 + b0) */
if ((res = mp_add(&a2, &a1, &tmp1)) != MP_OKAY) {
@@ -158,127 +160,127 @@ int mp_toom_mul(mp_int *a, mp_int *b, mp_int *c)
if ((res = mp_mul(&tmp1, &tmp2, &w2)) != MP_OKAY) {
goto ERR;
}
-
- /* now solve the matrix
-
+
+ /* now solve the matrix
+
0 0 0 0 1
1 2 4 8 16
1 1 1 1 1
16 8 4 2 1
1 0 0 0 0
-
- using 12 subtractions, 4 shifts,
- 2 small divisions and 1 small multiplication
+
+ using 12 subtractions, 4 shifts,
+ 2 small divisions and 1 small multiplication
*/
-
- /* r1 - r4 */
- if ((res = mp_sub(&w1, &w4, &w1)) != MP_OKAY) {
- goto ERR;
- }
- /* r3 - r0 */
- if ((res = mp_sub(&w3, &w0, &w3)) != MP_OKAY) {
- goto ERR;
- }
- /* r1/2 */
- if ((res = mp_div_2(&w1, &w1)) != MP_OKAY) {
- goto ERR;
- }
- /* r3/2 */
- if ((res = mp_div_2(&w3, &w3)) != MP_OKAY) {
- goto ERR;
- }
- /* r2 - r0 - r4 */
- if ((res = mp_sub(&w2, &w0, &w2)) != MP_OKAY) {
- goto ERR;
- }
- if ((res = mp_sub(&w2, &w4, &w2)) != MP_OKAY) {
- goto ERR;
- }
- /* r1 - r2 */
- if ((res = mp_sub(&w1, &w2, &w1)) != MP_OKAY) {
- goto ERR;
- }
- /* r3 - r2 */
- if ((res = mp_sub(&w3, &w2, &w3)) != MP_OKAY) {
- goto ERR;
- }
- /* r1 - 8r0 */
- if ((res = mp_mul_2d(&w0, 3, &tmp1)) != MP_OKAY) {
- goto ERR;
- }
- if ((res = mp_sub(&w1, &tmp1, &w1)) != MP_OKAY) {
- goto ERR;
- }
- /* r3 - 8r4 */
- if ((res = mp_mul_2d(&w4, 3, &tmp1)) != MP_OKAY) {
- goto ERR;
- }
- if ((res = mp_sub(&w3, &tmp1, &w3)) != MP_OKAY) {
- goto ERR;
- }
- /* 3r2 - r1 - r3 */
- if ((res = mp_mul_d(&w2, 3, &w2)) != MP_OKAY) {
- goto ERR;
- }
- if ((res = mp_sub(&w2, &w1, &w2)) != MP_OKAY) {
- goto ERR;
- }
- if ((res = mp_sub(&w2, &w3, &w2)) != MP_OKAY) {
- goto ERR;
- }
- /* r1 - r2 */
- if ((res = mp_sub(&w1, &w2, &w1)) != MP_OKAY) {
- goto ERR;
- }
- /* r3 - r2 */
- if ((res = mp_sub(&w3, &w2, &w3)) != MP_OKAY) {
- goto ERR;
- }
- /* r1/3 */
- if ((res = mp_div_3(&w1, &w1, NULL)) != MP_OKAY) {
- goto ERR;
- }
- /* r3/3 */
- if ((res = mp_div_3(&w3, &w3, NULL)) != MP_OKAY) {
- goto ERR;
- }
-
- /* at this point shift W[n] by B*n */
- if ((res = mp_lshd(&w1, 1*B)) != MP_OKAY) {
- goto ERR;
- }
- if ((res = mp_lshd(&w2, 2*B)) != MP_OKAY) {
- goto ERR;
- }
- if ((res = mp_lshd(&w3, 3*B)) != MP_OKAY) {
- goto ERR;
- }
- if ((res = mp_lshd(&w4, 4*B)) != MP_OKAY) {
- goto ERR;
- }
-
- if ((res = mp_add(&w0, &w1, c)) != MP_OKAY) {
- goto ERR;
- }
- if ((res = mp_add(&w2, &w3, &tmp1)) != MP_OKAY) {
- goto ERR;
- }
- if ((res = mp_add(&w4, &tmp1, &tmp1)) != MP_OKAY) {
- goto ERR;
- }
- if ((res = mp_add(&tmp1, c, c)) != MP_OKAY) {
- goto ERR;
- }
-
+
+ /* r1 - r4 */
+ if ((res = mp_sub(&w1, &w4, &w1)) != MP_OKAY) {
+ goto ERR;
+ }
+ /* r3 - r0 */
+ if ((res = mp_sub(&w3, &w0, &w3)) != MP_OKAY) {
+ goto ERR;
+ }
+ /* r1/2 */
+ if ((res = mp_div_2(&w1, &w1)) != MP_OKAY) {
+ goto ERR;
+ }
+ /* r3/2 */
+ if ((res = mp_div_2(&w3, &w3)) != MP_OKAY) {
+ goto ERR;
+ }
+ /* r2 - r0 - r4 */
+ if ((res = mp_sub(&w2, &w0, &w2)) != MP_OKAY) {
+ goto ERR;
+ }
+ if ((res = mp_sub(&w2, &w4, &w2)) != MP_OKAY) {
+ goto ERR;
+ }
+ /* r1 - r2 */
+ if ((res = mp_sub(&w1, &w2, &w1)) != MP_OKAY) {
+ goto ERR;
+ }
+ /* r3 - r2 */
+ if ((res = mp_sub(&w3, &w2, &w3)) != MP_OKAY) {
+ goto ERR;
+ }
+ /* r1 - 8r0 */
+ if ((res = mp_mul_2d(&w0, 3, &tmp1)) != MP_OKAY) {
+ goto ERR;
+ }
+ if ((res = mp_sub(&w1, &tmp1, &w1)) != MP_OKAY) {
+ goto ERR;
+ }
+ /* r3 - 8r4 */
+ if ((res = mp_mul_2d(&w4, 3, &tmp1)) != MP_OKAY) {
+ goto ERR;
+ }
+ if ((res = mp_sub(&w3, &tmp1, &w3)) != MP_OKAY) {
+ goto ERR;
+ }
+ /* 3r2 - r1 - r3 */
+ if ((res = mp_mul_d(&w2, 3, &w2)) != MP_OKAY) {
+ goto ERR;
+ }
+ if ((res = mp_sub(&w2, &w1, &w2)) != MP_OKAY) {
+ goto ERR;
+ }
+ if ((res = mp_sub(&w2, &w3, &w2)) != MP_OKAY) {
+ goto ERR;
+ }
+ /* r1 - r2 */
+ if ((res = mp_sub(&w1, &w2, &w1)) != MP_OKAY) {
+ goto ERR;
+ }
+ /* r3 - r2 */
+ if ((res = mp_sub(&w3, &w2, &w3)) != MP_OKAY) {
+ goto ERR;
+ }
+ /* r1/3 */
+ if ((res = mp_div_3(&w1, &w1, NULL)) != MP_OKAY) {
+ goto ERR;
+ }
+ /* r3/3 */
+ if ((res = mp_div_3(&w3, &w3, NULL)) != MP_OKAY) {
+ goto ERR;
+ }
+
+ /* at this point shift W[n] by B*n */
+ if ((res = mp_lshd(&w1, 1*B)) != MP_OKAY) {
+ goto ERR;
+ }
+ if ((res = mp_lshd(&w2, 2*B)) != MP_OKAY) {
+ goto ERR;
+ }
+ if ((res = mp_lshd(&w3, 3*B)) != MP_OKAY) {
+ goto ERR;
+ }
+ if ((res = mp_lshd(&w4, 4*B)) != MP_OKAY) {
+ goto ERR;
+ }
+
+ if ((res = mp_add(&w0, &w1, c)) != MP_OKAY) {
+ goto ERR;
+ }
+ if ((res = mp_add(&w2, &w3, &tmp1)) != MP_OKAY) {
+ goto ERR;
+ }
+ if ((res = mp_add(&w4, &tmp1, &tmp1)) != MP_OKAY) {
+ goto ERR;
+ }
+ if ((res = mp_add(&tmp1, c, c)) != MP_OKAY) {
+ goto ERR;
+ }
+
ERR:
- mp_clear_multi(&w0, &w1, &w2, &w3, &w4,
- &a0, &a1, &a2, &b0, &b1,
- &b2, &tmp1, &tmp2, NULL);
- return res;
-}
-
+ mp_clear_multi(&w0, &w1, &w2, &w3, &w4,
+ &a0, &a1, &a2, &b0, &b1,
+ &b2, &tmp1, &tmp2, NULL);
+ return res;
+}
+
#endif
-/* $Source: /cvs/libtom/libtommath/bn_mp_toom_mul.c,v $ */
-/* $Revision: 1.3 $ */
-/* $Date: 2006/03/31 14:18:44 $ */
+/* $Source$ */
+/* $Revision$ */
+/* $Date$ */
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