void
mpn_mul_n (mp_ptr p, mp_srcptr a, mp_srcptr b, mp_size_t n)
{
ASSERT (n >= 1);
ASSERT (! MPN_OVERLAP_P (p, 2 * n, a, n));
ASSERT (! MPN_OVERLAP_P (p, 2 * n, b, n));
if (BELOW_THRESHOLD (n, MUL_KARATSUBA_THRESHOLD))
{
mpn_mul_basecase (p, a, n, b, n);
}
else if (BELOW_THRESHOLD (n, MUL_TOOM3_THRESHOLD))
{
/* Allocate workspace of fixed size on stack: fast! */
mp_limb_t ws[MPN_KARA_MUL_N_TSIZE (MUL_TOOM3_THRESHOLD_LIMIT-1)];
ASSERT (MUL_TOOM3_THRESHOLD <= MUL_TOOM3_THRESHOLD_LIMIT);
mpn_kara_mul_n (p, a, b, n, ws);
}
else if (BELOW_THRESHOLD (n, MUL_TOOM4_THRESHOLD))
{
mp_ptr ws;
TMP_SDECL;
TMP_SMARK;
ws = TMP_SALLOC_LIMBS (MPN_TOOM3_MUL_N_TSIZE (n));
mpn_toom3_mul_n (p, a, b, n, ws);
TMP_SFREE;
}
else if (BELOW_THRESHOLD (n, MUL_TOOM8H_THRESHOLD))
{
mpn_toom4_mul_n (p, a, b, n);
}
#if WANT_FFT || TUNE_PROGRAM_BUILD
else if (BELOW_THRESHOLD (n, MUL_FFT_FULL_THRESHOLD))
{
mpn_toom8h_mul (p, a, n, b, n);
}
#endif
else
#if WANT_FFT || TUNE_PROGRAM_BUILD
{
mpn_mul_fft_main(p, a, n, b, n);
}
#else
{
/* Toom8 for large operands. */
mpn_toom8h_mul (p, a, n, b, n);
}
#endif
}
mp_limb_t
mpn_mul (mp_ptr prodp,
mp_srcptr up, mp_size_t un,
mp_srcptr vp, mp_size_t vn)
{
mp_size_t l, k;
mp_limb_t c;
ASSERT (un >= vn);
ASSERT (vn >= 1);
ASSERT (! MPN_OVERLAP_P (prodp, un+vn, up, un));
ASSERT (! MPN_OVERLAP_P (prodp, un+vn, vp, vn));
if (un == vn)
{
if (up == vp)
{
mpn_sqr (prodp, up, un);
return prodp[2 * un - 1];
}
else
{
mpn_mul_n (prodp, up, vp, un);
return prodp[2 * un - 1];
}
}
if (vn < MUL_KARATSUBA_THRESHOLD)
{ /* plain schoolbook multiplication */
if (un <= MUL_BASECASE_MAX_UN)
mpn_mul_basecase (prodp, up, un, vp, vn);
else
{
/* We have un >> MUL_BASECASE_MAX_UN > vn. For better memory
locality, split up[] into MUL_BASECASE_MAX_UN pieces and multiply
these pieces with the vp[] operand. After each such partial
multiplication (but the last) we copy the most significant vn
limbs into a temporary buffer since that part would otherwise be
overwritten by the next multiplication. After the next
multiplication, we add it back. This illustrates the situation:
-->vn<--
| |<------- un ------->|
_____________________|
X /|
/XX__________________/ |
_____________________ |
X / |
/XX__________________/ |
_____________________ |
/ / |
/____________________/ |
==================================================================
The parts marked with X are the parts whose sums are copied into
the temporary buffer. */
mp_limb_t tp[MUL_KARATSUBA_THRESHOLD_LIMIT];
mp_limb_t cy;
ASSERT (MUL_KARATSUBA_THRESHOLD <= MUL_KARATSUBA_THRESHOLD_LIMIT);
mpn_mul_basecase (prodp, up, MUL_BASECASE_MAX_UN, vp, vn);
prodp += MUL_BASECASE_MAX_UN;
MPN_COPY (tp, prodp, vn); /* preserve high triangle */
up += MUL_BASECASE_MAX_UN;
un -= MUL_BASECASE_MAX_UN;
while (un > MUL_BASECASE_MAX_UN)
{
mpn_mul_basecase (prodp, up, MUL_BASECASE_MAX_UN, vp, vn);
cy = mpn_add_n (prodp, prodp, tp, vn); /* add back preserved triangle */
mpn_incr_u (prodp + vn, cy); /* safe? */
prodp += MUL_BASECASE_MAX_UN;
MPN_COPY (tp, prodp, vn); /* preserve high triangle */
up += MUL_BASECASE_MAX_UN;
un -= MUL_BASECASE_MAX_UN;
}
if (un > vn)
{
mpn_mul_basecase (prodp, up, un, vp, vn);
}
else
{
ASSERT_ALWAYS (un > 0);
mpn_mul_basecase (prodp, vp, vn, up, un);
}
cy = mpn_add_n (prodp, prodp, tp, vn); /* add back preserved triangle */
mpn_incr_u (prodp + vn, cy); /* safe? */
}
return prodp[un + vn - 1];
}
if (ABOVE_THRESHOLD (un + vn, 2*MUL_FFT_FULL_THRESHOLD)
&& ABOVE_THRESHOLD (3*vn, MUL_FFT_FULL_THRESHOLD))
{
mpn_mul_fft_main (prodp, up, un, vp, vn);
return prodp[un + vn - 1];
}
k = (un + 3)/4; // ceil(un/4)
#if GMP_NUMB_BITS == 32
if ((ABOVE_THRESHOLD (un + vn, 2*MUL_TOOM8H_THRESHOLD)) && (vn>=86) && (5*un <= 11*vn))
#else
if ((ABOVE_THRESHOLD (un + vn, 2*MUL_TOOM8H_THRESHOLD)) && (vn>=86) && (4*un <= 13*vn))
#endif
{
mpn_toom8h_mul(prodp, up, un, vp, vn);
return prodp[un + vn - 1];
}
if (ABOVE_THRESHOLD (un + vn, 2*MUL_TOOM4_THRESHOLD))
{
if (vn > 3*k)
{
mpn_toom4_mul(prodp, up, un, vp, vn);
return prodp[un + vn - 1];
} else
{
l = (un + 4)/5; // ceil(un/5)
if ((((vn > 9*k/4) && (un+vn <= 6*MUL_TOOM4_THRESHOLD))
|| ((vn > 2*l) && (un+vn > 6*MUL_TOOM4_THRESHOLD)))
&& (vn <= 3*l))
{
mpn_toom53_mul(prodp, up, un, vp, vn);
return prodp[un + vn - 1];
}
}
}
if (ABOVE_THRESHOLD (un + vn, 2*MUL_TOOM3_THRESHOLD) && (vn > k))
{
mp_ptr ws;
TMP_DECL;
TMP_MARK;
if (vn < 2*k) // un/2 >= vn > un/4
{
ws = TMP_ALLOC_LIMBS (MPN_TOOM3_MUL_TSIZE(un));
mpn_toom42_mul(prodp, up, un, vp, vn, ws);
TMP_FREE;
return prodp[un + vn - 1];
}
l = (un+2)/3; //ceil(u/3)
if (vn > 2*l) // un >= vn > 2un/3
{
ws = TMP_ALLOC_LIMBS (MPN_TOOM3_MUL_TSIZE(un));
mpn_toom3_mul(prodp, up, un, vp, vn, ws);
TMP_FREE;
return prodp[un + vn - 1];
} else // 2un/3 >= vn > un/3
{
ws = TMP_ALLOC_LIMBS (MPN_TOOM3_MUL_TSIZE(un));
mpn_toom32_mul(prodp, up, un, vp, vn, ws);
TMP_FREE;
return prodp[un + vn - 1];
}
}
mpn_mul_n (prodp, up, vp, vn);
if (un != vn)
{ mp_limb_t t;
mp_ptr ws;
TMP_DECL;
TMP_MARK;
prodp += vn;
l = vn;
up += vn;
un -= vn;
if (un < vn)
{
/* Swap u's and v's. */
MPN_SRCPTR_SWAP (up,un, vp,vn);
}
ws = TMP_ALLOC_LIMBS ((vn >= MUL_KARATSUBA_THRESHOLD ? vn : un) + vn);
t = 0;
while (vn >= MUL_KARATSUBA_THRESHOLD)
{
mpn_mul_n (ws, up, vp, vn);
if (l <= 2*vn)
{
t += mpn_add_n (prodp, prodp, ws, l);
if (l != 2*vn)
{
t = mpn_add_1 (prodp + l, ws + l, 2*vn - l, t);
l = 2*vn;
}
}
else
{
c = mpn_add_n (prodp, prodp, ws, 2*vn);
t += mpn_add_1 (prodp + 2*vn, prodp + 2*vn, l - 2*vn, c);
}
prodp += vn;
l -= vn;
up += vn;
un -= vn;
if (un < vn)
{
/* Swap u's and v's. */
MPN_SRCPTR_SWAP (up,un, vp,vn);
}
}
if (vn != 0)
{
mpn_mul_basecase (ws, up, un, vp, vn);
if (l <= un + vn)
{
t += mpn_add_n (prodp, prodp, ws, l);
if (l != un + vn)
t = mpn_add_1 (prodp + l, ws + l, un + vn - l, t);
}
else
{
c = mpn_add_n (prodp, prodp, ws, un + vn);
t += mpn_add_1 (prodp + un + vn, prodp + un + vn, l - un - vn, c);
}
}
TMP_FREE;
}
return prodp[un + vn - 1];
}
int
main(void)
{
mp_bitcnt_t depth, w;
flint_rand_t state;
printf("mul_fft_main....");
fflush(stdout);
flint_randinit(state);
_flint_rand_init_gmp(state);
for (depth = 6; depth <= 13; depth++)
{
for (w = 1; w <= 3 - (depth >= 12); w++)
{
int iter = 1 + 200*(depth <= 8) + 80*(depth <= 9) + 10*(depth <= 10), i;
for (i = 0; i < iter; i++)
{
mp_size_t n = (1UL<<depth);
mp_bitcnt_t bits1 = (n*w - (depth + 1))/2;
mp_size_t len1 = 2*n + n_randint(state, 2*n) + 1;
mp_size_t len2 = 2*n + 2 - len1 + n_randint(state, 2*n);
mp_bitcnt_t b1 = len1*bits1, b2;
mp_size_t n1, n2;
mp_size_t j;
mp_limb_t * i1, *i2, *r1, *r2;
if (len2 <= 0)
len2 = 2*n + n_randint(state, 2*n) + 1;
b2 = len2*bits1;
n1 = (b1 - 1)/FLINT_BITS + 1;
n2 = (b2 - 1)/FLINT_BITS + 1;
if (n1 < n2) /* ensure b1 >= b2 */
{
mp_size_t t = n1;
mp_bitcnt_t tb = b1;
n1 = n2;
b1 = b2;
n2 = t;
b2 = tb;
}
i1 = flint_malloc(3*(n1 + n2)*sizeof(mp_limb_t));
i2 = i1 + n1;
r1 = i2 + n2;
r2 = r1 + n1 + n2;
mpn_urandomb(i1, state->gmp_state, b1);
mpn_urandomb(i2, state->gmp_state, b2);
mpn_mul(r2, i1, n1, i2, n2);
mpn_mul_fft_main(r1, i1, n1, i2, n2);
for (j = 0; j < n1 + n2; j++)
{
if (r1[j] != r2[j])
{
printf("error in limb %ld, %lx != %lx\n", j, r1[j], r2[j]);
abort();
}
}
flint_free(i1);
}
}
}
flint_randclear(state);
printf("PASS\n");
return 0;
}
