|
|
@@ -213,15 +213,28 @@ static void internal_sub(const BignumInt *a, const BignumInt *b,
|
|
|
* Compute c = a * b.
|
|
|
* Input is in the first len words of a and b.
|
|
|
* Result is returned in the first 2*len words of c.
|
|
|
+ *
|
|
|
+ * 'scratch' must point to an array of BignumInt of size at least
|
|
|
+ * mul_compute_scratch(len). (This covers the needs of internal_mul
|
|
|
+ * and all its recursive calls to itself.)
|
|
|
*/
|
|
|
#define KARATSUBA_THRESHOLD 50
|
|
|
+static int mul_compute_scratch(int len)
|
|
|
+{
|
|
|
+ int ret = 0;
|
|
|
+ while (len > KARATSUBA_THRESHOLD) {
|
|
|
+ int toplen = len/2, botlen = len - toplen; /* botlen is the bigger */
|
|
|
+ int midlen = botlen + 1;
|
|
|
+ ret += 4*midlen;
|
|
|
+ len = midlen;
|
|
|
+ }
|
|
|
+ return ret;
|
|
|
+}
|
|
|
static void internal_mul(const BignumInt *a, const BignumInt *b,
|
|
|
- BignumInt *c, int len)
|
|
|
+ BignumInt *c, int len, BignumInt *scratch)
|
|
|
{
|
|
|
- int i, j;
|
|
|
- BignumDblInt t;
|
|
|
-
|
|
|
if (len > KARATSUBA_THRESHOLD) {
|
|
|
+ int i;
|
|
|
|
|
|
/*
|
|
|
* Karatsuba divide-and-conquer algorithm. Cut each input in
|
|
|
@@ -257,7 +270,6 @@ static void internal_mul(const BignumInt *a, const BignumInt *b,
|
|
|
|
|
|
int toplen = len/2, botlen = len - toplen; /* botlen is the bigger */
|
|
|
int midlen = botlen + 1;
|
|
|
- BignumInt *scratch;
|
|
|
BignumDblInt carry;
|
|
|
#ifdef KARA_DEBUG
|
|
|
int i;
|
|
|
@@ -285,7 +297,7 @@ static void internal_mul(const BignumInt *a, const BignumInt *b,
|
|
|
#endif
|
|
|
|
|
|
/* a_1 b_1 */
|
|
|
- internal_mul(a, b, c, toplen);
|
|
|
+ internal_mul(a, b, c, toplen, scratch);
|
|
|
#ifdef KARA_DEBUG
|
|
|
printf("a1b1 = 0x");
|
|
|
for (i = 0; i < 2*toplen; i++) {
|
|
|
@@ -295,7 +307,7 @@ static void internal_mul(const BignumInt *a, const BignumInt *b,
|
|
|
#endif
|
|
|
|
|
|
/* a_0 b_0 */
|
|
|
- internal_mul(a + toplen, b + toplen, c + 2*toplen, botlen);
|
|
|
+ internal_mul(a + toplen, b + toplen, c + 2*toplen, botlen, scratch);
|
|
|
#ifdef KARA_DEBUG
|
|
|
printf("a0b0 = 0x");
|
|
|
for (i = 0; i < 2*botlen; i++) {
|
|
|
@@ -304,23 +316,14 @@ static void internal_mul(const BignumInt *a, const BignumInt *b,
|
|
|
printf("\n");
|
|
|
#endif
|
|
|
|
|
|
- /*
|
|
|
- * We must allocate scratch space for the central coefficient,
|
|
|
- * and also for the two input values that we multiply when
|
|
|
- * computing it. Since either or both may carry into the
|
|
|
- * (botlen+1)th word, we must use a slightly longer length
|
|
|
- * 'midlen'.
|
|
|
- */
|
|
|
- scratch = snewn(4 * midlen, BignumInt);
|
|
|
-
|
|
|
/* Zero padding. midlen exceeds toplen by at most 2, so just
|
|
|
* zero the first two words of each input and the rest will be
|
|
|
* copied over. */
|
|
|
scratch[0] = scratch[1] = scratch[midlen] = scratch[midlen+1] = 0;
|
|
|
|
|
|
- for (j = 0; j < toplen; j++) {
|
|
|
- scratch[midlen - toplen + j] = a[j]; /* a_1 */
|
|
|
- scratch[2*midlen - toplen + j] = b[j]; /* b_1 */
|
|
|
+ for (i = 0; i < toplen; i++) {
|
|
|
+ scratch[midlen - toplen + i] = a[i]; /* a_1 */
|
|
|
+ scratch[2*midlen - toplen + i] = b[i]; /* b_1 */
|
|
|
}
|
|
|
|
|
|
/* compute a_1 + a_0 */
|
|
|
@@ -346,7 +349,8 @@ static void internal_mul(const BignumInt *a, const BignumInt *b,
|
|
|
/*
|
|
|
* Now we can do the third multiplication.
|
|
|
*/
|
|
|
- internal_mul(scratch, scratch + midlen, scratch + 2*midlen, midlen);
|
|
|
+ internal_mul(scratch, scratch + midlen, scratch + 2*midlen, midlen,
|
|
|
+ scratch + 4*midlen);
|
|
|
#ifdef KARA_DEBUG
|
|
|
printf("a1plusa0timesb1plusb0 = 0x");
|
|
|
for (i = 0; i < 2*midlen; i++) {
|
|
|
@@ -361,8 +365,8 @@ static void internal_mul(const BignumInt *a, const BignumInt *b,
|
|
|
* product to obtain the middle one.
|
|
|
*/
|
|
|
scratch[0] = scratch[1] = scratch[2] = scratch[3] = 0;
|
|
|
- for (j = 0; j < 2*toplen; j++)
|
|
|
- scratch[2*midlen - 2*toplen + j] = c[j];
|
|
|
+ for (i = 0; i < 2*toplen; i++)
|
|
|
+ scratch[2*midlen - 2*toplen + i] = c[i];
|
|
|
scratch[1] = internal_add(scratch+2, c + 2*toplen,
|
|
|
scratch+2, 2*botlen);
|
|
|
#ifdef KARA_DEBUG
|
|
|
@@ -392,13 +396,13 @@ static void internal_mul(const BignumInt *a, const BignumInt *b,
|
|
|
carry = internal_add(c + 2*len - botlen - 2*midlen,
|
|
|
scratch + 2*midlen,
|
|
|
c + 2*len - botlen - 2*midlen, 2*midlen);
|
|
|
- j = 2*len - botlen - 2*midlen - 1;
|
|
|
+ i = 2*len - botlen - 2*midlen - 1;
|
|
|
while (carry) {
|
|
|
- assert(j >= 0);
|
|
|
- carry += c[j];
|
|
|
- c[j] = (BignumInt)carry;
|
|
|
+ assert(i >= 0);
|
|
|
+ carry += c[i];
|
|
|
+ c[i] = (BignumInt)carry;
|
|
|
carry >>= BIGNUM_INT_BITS;
|
|
|
- j--;
|
|
|
+ i--;
|
|
|
}
|
|
|
#ifdef KARA_DEBUG
|
|
|
printf("ab = 0x");
|
|
|
@@ -408,29 +412,28 @@ static void internal_mul(const BignumInt *a, const BignumInt *b,
|
|
|
printf("\n");
|
|
|
#endif
|
|
|
|
|
|
- /* Free scratch. */
|
|
|
- for (j = 0; j < 4 * midlen; j++)
|
|
|
- scratch[j] = 0;
|
|
|
- sfree(scratch);
|
|
|
-
|
|
|
} else {
|
|
|
+ int i;
|
|
|
+ BignumInt carry;
|
|
|
+ BignumDblInt t;
|
|
|
+ const BignumInt *ap, *bp;
|
|
|
+ BignumInt *cp, *cps;
|
|
|
|
|
|
/*
|
|
|
* Multiply in the ordinary O(N^2) way.
|
|
|
*/
|
|
|
|
|
|
- for (j = 0; j < 2 * len; j++)
|
|
|
- c[j] = 0;
|
|
|
+ for (i = 0; i < 2 * len; i++)
|
|
|
+ c[i] = 0;
|
|
|
|
|
|
- for (i = len - 1; i >= 0; i--) {
|
|
|
- t = 0;
|
|
|
- for (j = len - 1; j >= 0; j--) {
|
|
|
- t += MUL_WORD(a[i], (BignumDblInt) b[j]);
|
|
|
- t += (BignumDblInt) c[i + j + 1];
|
|
|
- c[i + j + 1] = (BignumInt) t;
|
|
|
- t = t >> BIGNUM_INT_BITS;
|
|
|
+ for (cps = c + 2*len, ap = a + len; ap-- > a; cps--) {
|
|
|
+ carry = 0;
|
|
|
+ for (cp = cps, bp = b + len; cp--, bp-- > b ;) {
|
|
|
+ t = (MUL_WORD(*ap, *bp) + carry) + *cp;
|
|
|
+ *cp = (BignumInt) t;
|
|
|
+ carry = t >> BIGNUM_INT_BITS;
|
|
|
}
|
|
|
- c[i] = (BignumInt) t;
|
|
|
+ *cp = carry;
|
|
|
}
|
|
|
}
|
|
|
}
|
|
|
@@ -441,12 +444,10 @@ static void internal_mul(const BignumInt *a, const BignumInt *b,
|
|
|
* (everything above that is thrown away).
|
|
|
*/
|
|
|
static void internal_mul_low(const BignumInt *a, const BignumInt *b,
|
|
|
- BignumInt *c, int len)
|
|
|
+ BignumInt *c, int len, BignumInt *scratch)
|
|
|
{
|
|
|
- int i, j;
|
|
|
- BignumDblInt t;
|
|
|
-
|
|
|
if (len > KARATSUBA_THRESHOLD) {
|
|
|
+ int i;
|
|
|
|
|
|
/*
|
|
|
* Karatsuba-aware version of internal_mul_low. As before, we
|
|
|
@@ -481,29 +482,30 @@ static void internal_mul_low(const BignumInt *a, const BignumInt *b,
|
|
|
*/
|
|
|
|
|
|
int toplen = len/2, botlen = len - toplen; /* botlen is the bigger */
|
|
|
- BignumInt *scratch;
|
|
|
|
|
|
/*
|
|
|
- * Allocate scratch space for the various bits and pieces
|
|
|
- * we're going to be adding together. We need botlen*2 words
|
|
|
- * for a_0 b_0 (though we may end up throwing away its topmost
|
|
|
- * word), and toplen words for each of a_1 b_0 and a_0 b_1.
|
|
|
- * That adds up to exactly 2*len.
|
|
|
+ * Scratch space for the various bits and pieces we're going
|
|
|
+ * to be adding together: we need botlen*2 words for a_0 b_0
|
|
|
+ * (though we may end up throwing away its topmost word), and
|
|
|
+ * toplen words for each of a_1 b_0 and a_0 b_1. That adds up
|
|
|
+ * to exactly 2*len.
|
|
|
*/
|
|
|
- scratch = snewn(len*2, BignumInt);
|
|
|
|
|
|
/* a_0 b_0 */
|
|
|
- internal_mul(a + toplen, b + toplen, scratch + 2*toplen, botlen);
|
|
|
+ internal_mul(a + toplen, b + toplen, scratch + 2*toplen, botlen,
|
|
|
+ scratch + 2*len);
|
|
|
|
|
|
/* a_1 b_0 */
|
|
|
- internal_mul_low(a, b + len - toplen, scratch + toplen, toplen);
|
|
|
+ internal_mul_low(a, b + len - toplen, scratch + toplen, toplen,
|
|
|
+ scratch + 2*len);
|
|
|
|
|
|
/* a_0 b_1 */
|
|
|
- internal_mul_low(a + len - toplen, b, scratch, toplen);
|
|
|
+ internal_mul_low(a + len - toplen, b, scratch, toplen,
|
|
|
+ scratch + 2*len);
|
|
|
|
|
|
/* Copy the bottom half of the big coefficient into place */
|
|
|
- for (j = 0; j < botlen; j++)
|
|
|
- c[toplen + j] = scratch[2*toplen + botlen + j];
|
|
|
+ for (i = 0; i < botlen; i++)
|
|
|
+ c[toplen + i] = scratch[2*toplen + botlen + i];
|
|
|
|
|
|
/* Add the two small coefficients, throwing away the returned carry */
|
|
|
internal_add(scratch, scratch + toplen, scratch, toplen);
|
|
|
@@ -512,26 +514,28 @@ static void internal_mul_low(const BignumInt *a, const BignumInt *b,
|
|
|
internal_add(scratch, scratch + 2*toplen + botlen - toplen,
|
|
|
c, toplen);
|
|
|
|
|
|
- /* Free scratch. */
|
|
|
- for (j = 0; j < len*2; j++)
|
|
|
- scratch[j] = 0;
|
|
|
- sfree(scratch);
|
|
|
-
|
|
|
} else {
|
|
|
+ int i;
|
|
|
+ BignumInt carry;
|
|
|
+ BignumDblInt t;
|
|
|
+ const BignumInt *ap, *bp;
|
|
|
+ BignumInt *cp, *cps;
|
|
|
|
|
|
- for (j = 0; j < len; j++)
|
|
|
- c[j] = 0;
|
|
|
+ /*
|
|
|
+ * Multiply in the ordinary O(N^2) way.
|
|
|
+ */
|
|
|
|
|
|
- for (i = len - 1; i >= 0; i--) {
|
|
|
- t = 0;
|
|
|
- for (j = len - 1; j >= len - i - 1; j--) {
|
|
|
- t += MUL_WORD(a[i], (BignumDblInt) b[j]);
|
|
|
- t += (BignumDblInt) c[i + j + 1 - len];
|
|
|
- c[i + j + 1 - len] = (BignumInt) t;
|
|
|
- t = t >> BIGNUM_INT_BITS;
|
|
|
+ for (i = 0; i < len; i++)
|
|
|
+ c[i] = 0;
|
|
|
+
|
|
|
+ for (cps = c + len, ap = a + len; ap-- > a; cps--) {
|
|
|
+ carry = 0;
|
|
|
+ for (cp = cps, bp = b + len; bp--, cp-- > c ;) {
|
|
|
+ t = (MUL_WORD(*ap, *bp) + carry) + *cp;
|
|
|
+ *cp = (BignumInt) t;
|
|
|
+ carry = t >> BIGNUM_INT_BITS;
|
|
|
}
|
|
|
}
|
|
|
-
|
|
|
}
|
|
|
}
|
|
|
|
|
|
@@ -546,8 +550,8 @@ static void internal_mul_low(const BignumInt *a, const BignumInt *b,
|
|
|
* each, containing respectively n and the multiplicative inverse of
|
|
|
* -n mod r.
|
|
|
*
|
|
|
- * 'tmp' is an array of at least '3*len' BignumInts used as scratch
|
|
|
- * space.
|
|
|
+ * 'tmp' is an array of BignumInt used as scratch space, of length at
|
|
|
+ * least 3*len + mul_compute_scratch(len).
|
|
|
*/
|
|
|
static void monty_reduce(BignumInt *x, const BignumInt *n,
|
|
|
const BignumInt *mninv, BignumInt *tmp, int len)
|
|
|
@@ -560,7 +564,7 @@ static void monty_reduce(BignumInt *x, const BignumInt *n,
|
|
|
* that mn is congruent to -x mod r. Hence, mn+x is an exact
|
|
|
* multiple of r, and is also (obviously) congruent to x mod n.
|
|
|
*/
|
|
|
- internal_mul_low(x + len, mninv, tmp, len);
|
|
|
+ internal_mul_low(x + len, mninv, tmp, len, tmp + 3*len);
|
|
|
|
|
|
/*
|
|
|
* Compute t = (mn+x)/r in ordinary, non-modular, integer
|
|
|
@@ -571,7 +575,7 @@ static void monty_reduce(BignumInt *x, const BignumInt *n,
|
|
|
* significant half of the 'x' array, so then we must shift it
|
|
|
* down.
|
|
|
*/
|
|
|
- internal_mul(tmp, n, tmp+len, len);
|
|
|
+ internal_mul(tmp, n, tmp+len, len, tmp + 3*len);
|
|
|
carry = internal_add(x, tmp+len, x, 2*len);
|
|
|
for (i = 0; i < len; i++)
|
|
|
x[len + i] = x[i], x[i] = 0;
|
|
|
@@ -721,9 +725,9 @@ static void internal_mod(BignumInt *a, int alen,
|
|
|
*/
|
|
|
Bignum modpow_simple(Bignum base_in, Bignum exp, Bignum mod)
|
|
|
{
|
|
|
- BignumInt *a, *b, *n, *m;
|
|
|
+ BignumInt *a, *b, *n, *m, *scratch;
|
|
|
int mshift;
|
|
|
- int mlen, i, j;
|
|
|
+ int mlen, scratchlen, i, j;
|
|
|
Bignum base, result;
|
|
|
|
|
|
/*
|
|
|
@@ -770,6 +774,10 @@ Bignum modpow_simple(Bignum base_in, Bignum exp, Bignum mod)
|
|
|
a[i] = 0;
|
|
|
a[2 * mlen - 1] = 1;
|
|
|
|
|
|
+ /* Scratch space for multiplies */
|
|
|
+ scratchlen = mul_compute_scratch(mlen);
|
|
|
+ scratch = snewn(scratchlen, BignumInt);
|
|
|
+
|
|
|
/* Skip leading zero bits of exp. */
|
|
|
i = 0;
|
|
|
j = BIGNUM_INT_BITS-1;
|
|
|
@@ -784,10 +792,10 @@ Bignum modpow_simple(Bignum base_in, Bignum exp, Bignum mod)
|
|
|
/* Main computation */
|
|
|
while (i < (int)exp[0]) {
|
|
|
while (j >= 0) {
|
|
|
- internal_mul(a + mlen, a + mlen, b, mlen);
|
|
|
+ internal_mul(a + mlen, a + mlen, b, mlen, scratch);
|
|
|
internal_mod(b, mlen * 2, m, mlen, NULL, 0);
|
|
|
if ((exp[exp[0] - i] & (1 << j)) != 0) {
|
|
|
- internal_mul(b + mlen, n, a, mlen);
|
|
|
+ internal_mul(b + mlen, n, a, mlen, scratch);
|
|
|
internal_mod(a, mlen * 2, m, mlen, NULL, 0);
|
|
|
} else {
|
|
|
BignumInt *t;
|
|
|
@@ -822,6 +830,9 @@ Bignum modpow_simple(Bignum base_in, Bignum exp, Bignum mod)
|
|
|
for (i = 0; i < 2 * mlen; i++)
|
|
|
a[i] = 0;
|
|
|
sfree(a);
|
|
|
+ for (i = 0; i < scratchlen; i++)
|
|
|
+ scratch[i] = 0;
|
|
|
+ sfree(scratch);
|
|
|
for (i = 0; i < 2 * mlen; i++)
|
|
|
b[i] = 0;
|
|
|
sfree(b);
|
|
|
@@ -843,8 +854,8 @@ Bignum modpow_simple(Bignum base_in, Bignum exp, Bignum mod)
|
|
|
*/
|
|
|
Bignum modpow(Bignum base_in, Bignum exp, Bignum mod)
|
|
|
{
|
|
|
- BignumInt *a, *b, *x, *n, *mninv, *tmp;
|
|
|
- int len, i, j;
|
|
|
+ BignumInt *a, *b, *x, *n, *mninv, *scratch;
|
|
|
+ int len, scratchlen, i, j;
|
|
|
Bignum base, base2, r, rn, inv, result;
|
|
|
|
|
|
/*
|
|
|
@@ -917,7 +928,9 @@ Bignum modpow(Bignum base_in, Bignum exp, Bignum mod)
|
|
|
a[2*len - 1 - j] = (j < rn[0] ? rn[j + 1] : 0);
|
|
|
freebn(rn);
|
|
|
|
|
|
- tmp = snewn(3*len, BignumInt);
|
|
|
+ /* Scratch space for multiplies */
|
|
|
+ scratchlen = 3*len + mul_compute_scratch(len);
|
|
|
+ scratch = snewn(scratchlen, BignumInt);
|
|
|
|
|
|
/* Skip leading zero bits of exp. */
|
|
|
i = 0;
|
|
|
@@ -933,11 +946,11 @@ Bignum modpow(Bignum base_in, Bignum exp, Bignum mod)
|
|
|
/* Main computation */
|
|
|
while (i < (int)exp[0]) {
|
|
|
while (j >= 0) {
|
|
|
- internal_mul(a + len, a + len, b, len);
|
|
|
- monty_reduce(b, n, mninv, tmp, len);
|
|
|
+ internal_mul(a + len, a + len, b, len, scratch);
|
|
|
+ monty_reduce(b, n, mninv, scratch, len);
|
|
|
if ((exp[exp[0] - i] & (1 << j)) != 0) {
|
|
|
- internal_mul(b + len, x, a, len);
|
|
|
- monty_reduce(a, n, mninv, tmp, len);
|
|
|
+ internal_mul(b + len, x, a, len, scratch);
|
|
|
+ monty_reduce(a, n, mninv, scratch, len);
|
|
|
} else {
|
|
|
BignumInt *t;
|
|
|
t = a;
|
|
|
@@ -954,7 +967,7 @@ Bignum modpow(Bignum base_in, Bignum exp, Bignum mod)
|
|
|
* Final monty_reduce to get back from the adjusted Montgomery
|
|
|
* representation.
|
|
|
*/
|
|
|
- monty_reduce(a, n, mninv, tmp, len);
|
|
|
+ monty_reduce(a, n, mninv, scratch, len);
|
|
|
|
|
|
/* Copy result to buffer */
|
|
|
result = newbn(mod[0]);
|
|
|
@@ -964,9 +977,9 @@ Bignum modpow(Bignum base_in, Bignum exp, Bignum mod)
|
|
|
result[0]--;
|
|
|
|
|
|
/* Free temporary arrays */
|
|
|
- for (i = 0; i < 3 * len; i++)
|
|
|
- tmp[i] = 0;
|
|
|
- sfree(tmp);
|
|
|
+ for (i = 0; i < scratchlen; i++)
|
|
|
+ scratch[i] = 0;
|
|
|
+ sfree(scratch);
|
|
|
for (i = 0; i < 2 * len; i++)
|
|
|
a[i] = 0;
|
|
|
sfree(a);
|
|
|
@@ -993,8 +1006,8 @@ Bignum modpow(Bignum base_in, Bignum exp, Bignum mod)
|
|
|
*/
|
|
|
Bignum modmul(Bignum p, Bignum q, Bignum mod)
|
|
|
{
|
|
|
- BignumInt *a, *n, *m, *o;
|
|
|
- int mshift;
|
|
|
+ BignumInt *a, *n, *m, *o, *scratch;
|
|
|
+ int mshift, scratchlen;
|
|
|
int pqlen, mlen, rlen, i, j;
|
|
|
Bignum result;
|
|
|
|
|
|
@@ -1036,8 +1049,12 @@ Bignum modmul(Bignum p, Bignum q, Bignum mod)
|
|
|
/* Allocate a of size 2*pqlen for result */
|
|
|
a = snewn(2 * pqlen, BignumInt);
|
|
|
|
|
|
+ /* Scratch space for multiplies */
|
|
|
+ scratchlen = mul_compute_scratch(pqlen);
|
|
|
+ scratch = snewn(scratchlen, BignumInt);
|
|
|
+
|
|
|
/* Main computation */
|
|
|
- internal_mul(n, o, a, pqlen);
|
|
|
+ internal_mul(n, o, a, pqlen, scratch);
|
|
|
internal_mod(a, pqlen * 2, m, mlen, NULL, 0);
|
|
|
|
|
|
/* Fixup result in case the modulus was shifted */
|
|
|
@@ -1059,6 +1076,9 @@ Bignum modmul(Bignum p, Bignum q, Bignum mod)
|
|
|
result[0]--;
|
|
|
|
|
|
/* Free temporary arrays */
|
|
|
+ for (i = 0; i < scratchlen; i++)
|
|
|
+ scratch[i] = 0;
|
|
|
+ sfree(scratch);
|
|
|
for (i = 0; i < 2 * pqlen; i++)
|
|
|
a[i] = 0;
|
|
|
sfree(a);
|
|
|
@@ -1347,18 +1367,21 @@ Bignum bigmuladd(Bignum a, Bignum b, Bignum addend)
|
|
|
int alen = a[0], blen = b[0];
|
|
|
int mlen = (alen > blen ? alen : blen);
|
|
|
int rlen, i, maxspot;
|
|
|
+ int wslen;
|
|
|
BignumInt *workspace;
|
|
|
Bignum ret;
|
|
|
|
|
|
- /* mlen space for a, mlen space for b, 2*mlen for result */
|
|
|
- workspace = snewn(mlen * 4, BignumInt);
|
|
|
+ /* mlen space for a, mlen space for b, 2*mlen for result,
|
|
|
+ * plus scratch space for multiplication */
|
|
|
+ wslen = mlen * 4 + mul_compute_scratch(mlen);
|
|
|
+ workspace = snewn(wslen, BignumInt);
|
|
|
for (i = 0; i < mlen; i++) {
|
|
|
workspace[0 * mlen + i] = (mlen - i <= (int)a[0] ? a[mlen - i] : 0);
|
|
|
workspace[1 * mlen + i] = (mlen - i <= (int)b[0] ? b[mlen - i] : 0);
|
|
|
}
|
|
|
|
|
|
internal_mul(workspace + 0 * mlen, workspace + 1 * mlen,
|
|
|
- workspace + 2 * mlen, mlen);
|
|
|
+ workspace + 2 * mlen, mlen, workspace + 4 * mlen);
|
|
|
|
|
|
/* now just copy the result back */
|
|
|
rlen = alen + blen + 1;
|
|
|
@@ -1387,6 +1410,8 @@ Bignum bigmuladd(Bignum a, Bignum b, Bignum addend)
|
|
|
}
|
|
|
ret[0] = maxspot;
|
|
|
|
|
|
+ for (i = 0; i < wslen; i++)
|
|
|
+ workspace[i] = 0;
|
|
|
sfree(workspace);
|
|
|
return ret;
|
|
|
}
|