/* (rp, 2n) = (xp, n)*(yp, n) */
void
mpn_mulhigh_n (mp_ptr rp, mp_srcptr xp, mp_srcptr yp, mp_size_t n)
{
mp_limb_t t;
ASSERT(n > 0);
ASSERT_MPN(xp, n);
ASSERT_MPN(yp, n);
ASSERT(!MPN_OVERLAP_P(rp, 2 * n, xp, n));
ASSERT(!MPN_OVERLAP_P(rp, 2 * n, yp, n));
if (BELOW_THRESHOLD(n, MULHIGH_BASECASE_THRESHOLD))
{
mpn_mul_basecase(rp, xp, n, yp, n);
return;
}
if (ABOVE_THRESHOLD (n, MULHIGH_MUL_THRESHOLD))
{
mpn_mul_n(rp, xp, yp, n);
return;
}
mpn_mulshort_n(rp, xp, yp, n);
t = rp[n - 1] + n - 2;
if (UNLIKELY(t < n - 2))
mpn_mul_n(rp, xp, yp, n);
return;
}
// k degree poly so have k+1 coeffs and first k are size n
// k>3 so we can do the first add unconditionally
int mpn_toom_eval_pm1(mp_ptr pp,mp_ptr mp,unsigned int k,mp_srcptr xp,mp_size_t n,mp_size_t m,mp_ptr tp)
{int isneg=0;unsigned int i;
ASSERT(k>3);ASSERT(n>=m);ASSERT(m>0);ASSERT_MPN(xp,n*k+m);
//ASSERT_SPACE(pp,n+1);ASSERT_SPACE(mp,n+1);ASSERT_SPACE(tp,n+1);
ASSERT(!MPN_OVERLAP_P(pp,n+1,mp,n+1));ASSERT(!MPN_OVERLAP_P(pp,n+1,xp,n*k+m));ASSERT(!MPN_OVERLAP_P(pp,n+1,tp,n+1));
ASSERT(!MPN_OVERLAP_P(mp,n+1,xp,n*k+m));ASSERT(!MPN_OVERLAP_P(xp,n*k+m,tp,n+1));
#if ! HAVE_NATIVE_mpn_sumdiff_n
ASSERT(!MPN_OVERLAP_P(mp,n+1,tp,n+1));
#endif
#if HAVE_NATIVE_mpn_addadd_n
if(k==4){pp[n]=mpn_add_n(pp,xp,xp+2*n,n);tp[n]=mpn_add_n(tp,xp+n,xp+3*n,n);}else
if(k==5){pp[n]=mpn_addadd_n(pp,xp,xp+2*n,xp+4*n,n);tp[n]=mpn_add_n(tp,xp+n,xp+3*n,n);}else
{pp[n]=mpn_addadd_n(pp,xp,xp+2*n,xp+4*n,n);tp[n]=mpn_addadd_n(tp,xp+n,xp+3*n,xp+5*n,n);
for(i=7;i<k-2;i+=4){pp[n]+=mpn_addadd_n(pp,pp,xp+(i-1)*n,xp+(i+1)*n,n);tp[n]+=mpn_addadd_n(tp,tp,xp+i*n,xp+(i+2)*n,n);}
if(k%4==3){pp[n]+=mpn_add_n(pp,pp,xp+(k-1)*n,n);}
if(k%4==0){pp[n]+=mpn_add_n(pp,pp,xp+(k-2)*n,n);tp[n]+=mpn_add_n(tp,tp,xp+(k-1)*n,n);}
if(k%4==1){pp[n]+=mpn_addadd_n(pp,pp,xp+(k-3)*n,xp+(k-1)*n,n);tp[n]+=mpn_add_n(tp,tp,xp+(k-2)*n,n);}}
if(k%2==0){pp[n]+=mpn_add(pp,pp,n,xp+k*n,m);}else{tp[n]+=mpn_add(tp,tp,n,xp+k*n,m);}
#else
// pp is xp+0 xp+2n xp+4n xp+6n ... xp+jn where j<=k-1
// mp is xp+1 xp+3n xp+5n xp+7n ... xp+jn where j<=k-1
pp[n]=mpn_add_n(pp,xp,xp+2*n,n);tp[n]=mpn_add_n(tp,xp+n,xp+3*n,n);
for(i=5;i<k;i+=2){pp[n]+=mpn_add_n(pp,pp,xp+(i-1)*n,n);tp[n]+=mpn_add_n(tp,tp,xp+i*n,n);}
if(k%2==1){pp[n]+=mpn_add_n(pp,pp,xp+(k-1)*n,n);tp[n]+=mpn_add(tp,tp,n,xp+k*n,m);}else{pp[n]+=mpn_add(pp,pp,n,xp+k*n,m);}
#endif
if(mpn_cmp(tp,pp,n+1)>0)isneg=-1;
#if HAVE_NATIVE_mpn_sumdiff_n
if(isneg==0){mpn_sumdiff_n(pp,mp,pp,tp,n+1);}else{mpn_sumdiff_n(pp,mp,tp,pp,n+1);}
#else
if(isneg==0){mpn_sub_n(mp,pp,tp,n+1);}else{mpn_sub_n(mp,tp,pp,n+1);}
mpn_add_n(pp,pp,tp,n+1);
#endif
return isneg;}
/* (rp, 2n) = (xp, n)*(yp, n) / B^n */
inline static void
mpn_mulshort_n_basecase(mp_ptr rp, mp_srcptr xp, mp_srcptr yp, mp_size_t n)
{
mp_size_t i, k;
#if GMP_NAIL_BITS==0
mp_limb_t t1, t2, t3;
#endif
ASSERT(n >= 3); /* this restriction doesn't make a lot of sense in general */
ASSERT_MPN(xp, n);
ASSERT_MPN(yp, n);
ASSERT(!MPN_OVERLAP_P (rp, 2 * n, xp, n));
ASSERT(!MPN_OVERLAP_P (rp, 2 * n, yp, n));
k = n - 2; /* so want short product sum_(i + j >= k) x[i]y[j]B^(i + j) */
#if GMP_NAIL_BITS!=0
rp[n] = mpn_mul_1(rp + k, xp + k, 2, yp[0]);
#else
umul_ppmm(t1, rp[k], xp[k], yp[0]);
umul_ppmm(t3, t2, xp[k + 1], yp[0]);
add_ssaaaa(rp[n], rp[k + 1], t3, t2, 0, t1);
#endif
for (i = 1; i <= n - 2; i++)
rp[n + i] = mpn_addmul_1 (rp + k, xp + k - i, 2 + i, yp[i]);
rp[n + n - 1] = mpn_addmul_1 (rp + n - 1, xp, n, yp[n - 1]);
return;
}
void
mpn_mulmid_n (mp_ptr rp, mp_srcptr ap, mp_srcptr bp, mp_size_t n)
{
ASSERT (n >= 1);
ASSERT (! MPN_OVERLAP_P (rp, n + 2, ap, 2*n - 1));
ASSERT (! MPN_OVERLAP_P (rp, n + 2, bp, n));
if (n < MULMID_TOOM42_THRESHOLD)
{
mpn_mulmid_basecase (rp, ap, 2*n - 1, bp, n);
}
else
{
mp_size_t k;
mp_ptr scratch;
TMP_DECL;
k = mpn_toom42_mulmid_itch (n);
if (k <= 1000) k = 1000;
TMP_MARK;
scratch = TMP_ALLOC_LIMBS (k);
mpn_toom42_mulmid (rp, ap, bp, n, scratch);
TMP_FREE;
}
}
void
my__gmpn_tdiv_qr (mp_ptr qp, mp_ptr rp, mp_size_t qxn,
mp_srcptr np, mp_size_t nn, mp_srcptr dp, mp_size_t dn)
{
ASSERT_ALWAYS (qxn == 0);
ASSERT (nn >= 0);
ASSERT (dn >= 0);
ASSERT (dn == 0 || dp[dn - 1] != 0);
ASSERT (! MPN_OVERLAP_P (qp, nn - dn + 1 + qxn, np, nn));
ASSERT (! MPN_OVERLAP_P (qp, nn - dn + 1 + qxn, dp, dn));
int adjust;
gmp_pi1_t dinv;
TMP_DECL;
TMP_MARK;
/* conservative tests for quotient size */
adjust = np[nn - 1] >= dp[dn - 1];
mp_ptr n2p, d2p;
mp_limb_t cy;
int cnt;
qp[nn - dn] = 0; /* zero high quotient limb */
count_leading_zeros (cnt, dp[dn - 1]);
cnt -= GMP_NAIL_BITS;
d2p = TMP_ALLOC_LIMBS (dn);
mpn_lshift (d2p, dp, dn, cnt);
for (int i=0; i<dn; i+=1)
{
printf("d2p %08x\n", *( (int*) (((void*)(d2p))+(i*4))));
}
n2p = TMP_ALLOC_LIMBS (nn + 1);
cy = mpn_lshift (n2p, np, nn, cnt);
for (int i=0; i<nn; i+=1)
{
printf("n2p %08x\n", *( (int*) (((void*)(n2p))+(i*4))));
}
n2p[nn] = cy;
nn += adjust;
printf("d2p[dn-1] = %08lx\nd2p[dn-2] = %08lx\n", d2p[dn-1], d2p[dn-2]);
invert_pi1 (dinv, d2p[dn - 1], d2p[dn - 2]);
printf("dinv %08lx\n", dinv.inv32);
my_mpn_sbpi1_div_qr (qp, n2p, nn, d2p, dn, dinv.inv32);
for (int i=0; i<nn; i+=1)
{
printf("inside qp %08x\n", *( (int*) (((void*)(qp))+(i*4))));
}
n2p[nn] = cy;
mpn_rshift (rp, n2p, dn, cnt);
TMP_FREE;
return;
}
/*
c is the top bits of the inputs, (fully reduced)
c & 2 is the top bit of y
c & 1 is the top bit of z
*/
int
mpn_mulmod_2expp1_basecase (mp_ptr xp, mp_srcptr yp, mp_srcptr zp,
int c, mpir_ui b, mp_ptr tp)
{
int cy, cz;
mp_size_t n, k;
cy = c & 2;
cz = c & 1;
n = BITS_TO_LIMBS (b);
k = GMP_NUMB_BITS * n - b;
ASSERT(b > 0);
ASSERT(n > 0);
ASSERT_MPN(yp, n);
ASSERT_MPN(zp, n);
ASSERT(!MPN_OVERLAP_P (tp, 2 * n, yp, n));
ASSERT(!MPN_OVERLAP_P (tp, 2 * n, zp, n));
ASSERT(MPN_SAME_OR_SEPARATE_P (xp, tp, n));
ASSERT(MPN_SAME_OR_SEPARATE_P (xp, tp + n, n));
ASSERT(k == 0 || yp[n - 1] >> (GMP_NUMB_BITS - k) == 0);
ASSERT(k == 0 || zp[n - 1] >> (GMP_NUMB_BITS - k) == 0);
#if WANT_ASSERT
{
mp_size_t t = n;
MPN_NORMALIZE(yp, t);
ASSERT(cy == 0 || t == 0);
t = n;
MPN_NORMALIZE(zp, t);
ASSERT(cz == 0 || t == 0);
}
#endif
if (LIKELY (cy == 0))
{
if (LIKELY (cz == 0))
{
c = mpn_mulmod_2expp1_internal (xp, yp, zp, b, tp);
}
else
{
c = mpn_neg_n (xp, yp, n);
c = mpn_add_1 (xp, xp, n, c);
xp[n - 1] &= GMP_NUMB_MASK >> k;
}
}
else
{
if (LIKELY (cz == 0))
void
mpn_invert (mp_ptr ip, mp_srcptr dp, mp_size_t n, mp_ptr scratch)
{
ASSERT (n > 0);
ASSERT (dp[n-1] & GMP_NUMB_HIGHBIT);
ASSERT (! MPN_OVERLAP_P (ip, n, dp, n));
ASSERT (! MPN_OVERLAP_P (ip, n, scratch, mpn_invertappr_itch(n)));
ASSERT (! MPN_OVERLAP_P (dp, n, scratch, mpn_invertappr_itch(n)));
if (n == 1)
invert_limb (*ip, *dp);
else {
TMP_DECL;
TMP_MARK;
if (BELOW_THRESHOLD (n, INV_APPR_THRESHOLD))
{
/* Maximum scratch needed by this branch: 2*n */
mp_size_t i;
mp_ptr xp;
xp = scratch; /* 2 * n limbs */
for (i = n - 1; i >= 0; i--)
xp[i] = GMP_NUMB_MAX;
mpn_com (xp + n, dp, n);
if (n == 2) {
mpn_divrem_2 (ip, 0, xp, 4, dp);
} else {
gmp_pi1_t inv;
invert_pi1 (inv, dp[n-1], dp[n-2]);
/* FIXME: should we use dcpi1_div_q, for big sizes? */
mpn_sbpi1_div_q (ip, xp, 2 * n, dp, n, inv.inv32);
}
}
else { /* Use approximated inverse; correct the result if needed. */
mp_limb_t e; /* The possible error in the approximate inverse */
ASSERT ( mpn_invert_itch (n) >= mpn_invertappr_itch (n) );
e = mpn_ni_invertappr (ip, dp, n, scratch);
if (UNLIKELY (e)) { /* Assume the error can only be "0" (no error) or "1". */
/* Code to detect and correct the "off by one" approximation. */
mpn_mul_n (scratch, ip, dp, n);
ASSERT_NOCARRY (mpn_add_n (scratch + n, scratch + n, dp, n));
if (! mpn_add (scratch, scratch, 2*n, dp, n))
MPN_INCR_U (ip, n, 1); /* The value was wrong, correct it. */
}
}
TMP_FREE;
}
}
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);
}
#if WANT_FFT || TUNE_PROGRAM_BUILD
else if (BELOW_THRESHOLD (n, MUL_FFT_THRESHOLD))
#else
else if (BELOW_THRESHOLD (n, MPN_TOOM3_MAX_N))
#endif
{
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 WANT_FFT || TUNE_PROGRAM_BUILD
{
/* The current FFT code allocates its own space. That should probably
change. */
mpn_mul_fft_full (p, a, n, b, n);
}
#else
{
/* Toom3 for large operands. Use workspace from the heap, as stack space
may be limited. Since n is at least MUL_TOOM3_THRESHOLD, multiplication
will take much longer than malloc()/free(). */
mp_ptr ws; mp_size_t ws_size;
ws_size = MPN_TOOM3_MUL_N_TSIZE (n);
ws = __GMP_ALLOCATE_FUNC_LIMBS (ws_size);
mpn_toom3_mul_n (p, a, b, n, ws);
__GMP_FREE_FUNC_LIMBS (ws, ws_size);
}
#endif
}
void
mpn_invert (mp_ptr ip, mp_srcptr dp, mp_size_t n, mp_ptr scratch)
{
ASSERT (n > 0);
ASSERT (dp[n-1] & GMP_NUMB_HIGHBIT);
ASSERT (! MPN_OVERLAP_P (ip, n, dp, n));
ASSERT (! MPN_OVERLAP_P (ip, n, scratch, mpn_invertappr_itch(n)));
ASSERT (! MPN_OVERLAP_P (dp, n, scratch, mpn_invertappr_itch(n)));
if (n == 1)
invert_limb (*ip, *dp);
else if (BELOW_THRESHOLD (n, INV_APPR_THRESHOLD))
{
/* Maximum scratch needed by this branch: 2*n */
mp_size_t i;
mp_ptr xp;
xp = scratch; /* 2 * n limbs */
/* n > 1 here */
i = n;
do
xp[--i] = GMP_NUMB_MAX;
while (i);
mpn_com (xp + n, dp, n);
if (n == 2) {
mpn_divrem_2 (ip, 0, xp, 4, dp);
} else {
gmp_pi1_t inv;
invert_pi1 (inv, dp[n-1], dp[n-2]);
/* FIXME: should we use dcpi1_div_q, for big sizes? */
mpn_sbpi1_div_q (ip, xp, 2 * n, dp, n, inv.inv32);
}
}
else { /* Use approximated inverse; correct the result if needed. */
mp_limb_t e; /* The possible error in the approximate inverse */
ASSERT ( mpn_invert_itch (n) >= mpn_invertappr_itch (n) );
e = mpn_ni_invertappr (ip, dp, n, scratch);
if (UNLIKELY (e)) { /* Assume the error can only be "0" (no error) or "1". */
/* Code to detect and correct the "off by one" approximation. */
mpn_mul_n (scratch, ip, dp, n);
e = mpn_add_n (scratch, scratch, dp, n); /* FIXME: we only need e.*/
if (LIKELY(e)) /* The high part can not give a carry by itself. */
e = mpn_add_nc (scratch + n, scratch + n, dp, n, e); /* FIXME:e */
/* If the value was wrong (no carry), correct it (increment). */
e ^= CNST_LIMB (1);
MPN_INCR_U (ip, n, e);
}
}
}
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_sumdiff_n(mp_ptr s,mp_ptr d,mp_srcptr x,mp_srcptr y,mp_size_t n)
{mp_limb_t ret;mp_ptr t;
ASSERT(n>0);
ASSERT_MPN(x,n);ASSERT_MPN(y,n);//ASSERT_SPACE(s,n);ASSERT_SPACE(d,n);
ASSERT(MPN_SAME_OR_SEPARATE_P(s,x,n));
ASSERT(MPN_SAME_OR_SEPARATE_P(s,y,n));
ASSERT(MPN_SAME_OR_SEPARATE_P(d,x,n));
ASSERT(MPN_SAME_OR_SEPARATE_P(d,y,n));
ASSERT(!MPN_OVERLAP_P(s,n,d,n));
if( (s==x && d==y)||(s==y && d==x) )
{t=__GMP_ALLOCATE_FUNC_LIMBS(n);
ret=mpn_sub_n(t,x,y,n);
ret+=2*mpn_add_n(s,x,y,n);
MPN_COPY(d,t,n);
__GMP_FREE_FUNC_LIMBS(t,n);
return ret;}
if(s==x || s==y)
{ret=mpn_sub_n(d,x,y,n);
ret+=2*mpn_add_n(s,x,y,n);
return ret;}
ret=2*mpn_add_n(s,x,y,n);
ret+=mpn_sub_n(d,x,y,n);
return ret;}
/*
mpn_dc_mullo_n requires a scratch space of 2*n limbs at tp.
It accepts tp == rp.
*/
static void
mpn_dc_mullo_n (mp_ptr rp, mp_srcptr xp, mp_srcptr yp, mp_size_t n, mp_ptr tp)
{
mp_size_t n2, n1;
ASSERT (n >= 2);
ASSERT (! MPN_OVERLAP_P (rp, n, xp, n));
ASSERT (! MPN_OVERLAP_P (rp, n, yp, n));
ASSERT (MPN_SAME_OR_SEPARATE2_P(rp, n, tp, 2*n));
/* Divide-and-conquer */
/* We need fractional approximation of the value 0 < a <= 1/2
giving the minimum in the function k=(1-a)^e/(1-2*a^e).
*/
if (MAYBE_range_basecase && BELOW_THRESHOLD (n, MUL_TOOM22_THRESHOLD*36/(36-11)))
n1 = n >> 1;
else if (MAYBE_range_toom22 && BELOW_THRESHOLD (n, MUL_TOOM33_THRESHOLD*36/(36-11)))
void
mpn_sqr (mp_ptr p, mp_srcptr a, mp_size_t n)
{
ASSERT (n >= 1);
ASSERT (! MPN_OVERLAP_P (p, 2 * n, a, n));
#if 0
/* FIXME: Can this be removed? */
if (n == 0)
return;
#endif
if (BELOW_THRESHOLD (n, SQR_BASECASE_THRESHOLD))
{ /* mul_basecase is faster than sqr_basecase on small sizes sometimes */
mpn_mul_basecase (p, a, n, a, n);
}
else if (BELOW_THRESHOLD (n, SQR_KARATSUBA_THRESHOLD))
{
mpn_sqr_basecase (p, a, n);
}
else if (BELOW_THRESHOLD (n, SQR_TOOM3_THRESHOLD))
{
/* Allocate workspace of fixed size on stack: fast! */
mp_limb_t ws[MPN_KARA_SQR_N_TSIZE (SQR_TOOM3_THRESHOLD_LIMIT-1)];
ASSERT (SQR_TOOM3_THRESHOLD <= SQR_TOOM3_THRESHOLD_LIMIT);
mpn_kara_sqr_n (p, a, n, ws);
}
else if (BELOW_THRESHOLD (n, SQR_TOOM4_THRESHOLD))
{
mp_ptr ws;
TMP_SDECL;
TMP_SMARK;
ws = TMP_SALLOC_LIMBS (MPN_TOOM3_SQR_N_TSIZE (n));
mpn_toom3_sqr_n (p, a, n, ws);
TMP_SFREE;
}
else if (BELOW_THRESHOLD (n, SQR_TOOM8_THRESHOLD))
{
mpn_toom4_sqr_n (p, a, n);
}
#if WANT_FFT || TUNE_PROGRAM_BUILD
else if (BELOW_THRESHOLD (n, SQR_FFT_FULL_THRESHOLD))
#else
else
#endif
{
mpn_toom8_sqr_n (p, a, n);
}
#if WANT_FFT || TUNE_PROGRAM_BUILD
else
{
void
mpn_sqr_n (mp_ptr prodp,
mp_srcptr up, mp_size_t un)
{
ASSERT (un >= 1);
ASSERT (! MPN_OVERLAP_P (prodp, 2*un, up, un));
/* FIXME: Can this be removed? */
if (un == 0)
return;
if (BELOW_THRESHOLD (un, SQR_BASECASE_THRESHOLD))
{ /* mul_basecase is faster than sqr_basecase on small sizes sometimes */
mpn_mul_basecase (prodp, up, un, up, un);
}
else if (BELOW_THRESHOLD (un, SQR_KARATSUBA_THRESHOLD))
{ /* plain schoolbook multiplication */
mpn_sqr_basecase (prodp, up, un);
}
else if (BELOW_THRESHOLD (un, SQR_TOOM3_THRESHOLD))
{ /* karatsuba multiplication */
mp_ptr tspace;
TMP_DECL (marker);
TMP_MARK (marker);
tspace = TMP_ALLOC_LIMBS (MPN_KARA_SQR_N_TSIZE (un));
mpn_kara_sqr_n (prodp, up, un, tspace);
TMP_FREE (marker);
}
#if WANT_FFT || TUNE_PROGRAM_BUILD
else if (BELOW_THRESHOLD (un, SQR_FFT_THRESHOLD))
#else
else
#endif
{ /* Toom3 multiplication.
Use workspace from the heap, as stack may be limited. Since n is
at least MUL_TOOM3_THRESHOLD, the multiplication will take much
longer than malloc()/free(). */
mp_ptr tspace;
mp_size_t tsize;
tsize = MPN_TOOM3_SQR_N_TSIZE (un);
tspace = __GMP_ALLOCATE_FUNC_LIMBS (tsize);
mpn_toom3_sqr_n (prodp, up, un, tspace);
__GMP_FREE_FUNC_LIMBS (tspace, tsize);
}
#if WANT_FFT || TUNE_PROGRAM_BUILD
else
{
/* Define our own squaring function, which uses mpn_sqr_basecase for its
allowed sizes, but its own code for larger sizes. */
static void
mpn_local_sqr (mp_ptr rp, mp_srcptr up, mp_size_t n, mp_ptr tp)
{
mp_size_t i;
ASSERT (n >= 1);
ASSERT (! MPN_OVERLAP_P (rp, 2*n, up, n));
if (BELOW_THRESHOLD (n, SQR_BASECASE_LIM))
{
mpn_sqr_basecase (rp, up, n);
return;
}
{
mp_limb_t ul, lpl;
ul = up[0];
umul_ppmm (rp[1], lpl, ul, ul << GMP_NAIL_BITS);
rp[0] = lpl >> GMP_NAIL_BITS;
}
if (n > 1)
{
mp_limb_t cy;
cy = mpn_mul_1 (tp, up + 1, n - 1, up[0]);
tp[n - 1] = cy;
for (i = 2; i < n; i++)
{
mp_limb_t cy;
cy = mpn_addmul_1 (tp + 2 * i - 2, up + i, n - i, up[i - 1]);
tp[n + i - 2] = cy;
}
MPN_SQR_DIAGONAL (rp + 2, up + 1, n - 1);
{
mp_limb_t cy;
#if HAVE_NATIVE_mpn_addlsh1_n
cy = mpn_addlsh1_n (rp + 1, rp + 1, tp, 2 * n - 2);
#else
cy = mpn_lshift (tp, tp, 2 * n - 2, 1);
cy += mpn_add_n (rp + 1, rp + 1, tp, 2 * n - 2);
#endif
rp[2 * n - 1] += cy;
}
}
}
mp_limb_t
mpn_sb_divrem_mn (mp_ptr qp,
mp_ptr np, mp_size_t nn,
mp_srcptr dp, mp_size_t dn)
{
mp_limb_t most_significant_q_limb = 0;
mp_size_t qn = nn - dn;
mp_size_t i;
mp_limb_t dx, d1, n0;
mp_limb_t dxinv;
int use_preinv;
ASSERT (dn > 2);
ASSERT (nn >= dn);
ASSERT (dp[dn-1] & GMP_NUMB_HIGHBIT);
ASSERT (! MPN_OVERLAP_P (np, nn, dp, dn));
ASSERT (! MPN_OVERLAP_P (qp, nn-dn, dp, dn));
ASSERT (! MPN_OVERLAP_P (qp, nn-dn, np, nn) || qp+dn >= np);
ASSERT_MPN (np, nn);
ASSERT_MPN (dp, dn);
np += qn;
dx = dp[dn - 1];
d1 = dp[dn - 2];
n0 = np[dn - 1];
if (n0 >= dx)
{
if (n0 > dx || mpn_cmp (np, dp, dn - 1) >= 0)
{
mpn_sub_n (np, np, dp, dn);
most_significant_q_limb = 1;
}
}
/* use_preinv is possibly a constant, but it's left to the compiler to
optimize away the unused code in that case. */
use_preinv = ABOVE_THRESHOLD (qn, DIV_SB_PREINV_THRESHOLD);
if (use_preinv)
invert_limb (dxinv, dx);
for (i = qn - 1; i >= 0; i--)
{
mp_limb_t q;
mp_limb_t nx;
mp_limb_t cy_limb;
nx = np[dn - 1]; /* FIXME: could get value from r1 */
np--;
if (nx == dx)
{
/* This might over-estimate q, but it's probably not worth
the extra code here to find out. */
q = GMP_NUMB_MASK;
#if 1
cy_limb = mpn_submul_1 (np, dp, dn, q);
#else
/* This should be faster on many machines */
cy_limb = mpn_sub_n (np + 1, np + 1, dp, dn);
cy = mpn_add_n (np, np, dp, dn);
np[dn] += cy;
#endif
if (nx != cy_limb)
{
mpn_add_n (np, np, dp, dn);
q--;
}
qp[i] = q;
}
else
{
mp_limb_t rx, r1, r0, p1, p0;
/* "workaround" avoids a problem with gcc 2.7.2.3 i386 register usage
when np[dn-1] is used in an asm statement like umul_ppmm in
udiv_qrnnd_preinv. The symptom is seg faults due to registers
being clobbered. gcc 2.95 i386 doesn't have the problem. */
{
mp_limb_t workaround = np[dn - 1];
if (use_preinv)
udiv_qrnnd_preinv (q, r1, nx, workaround, dx, dxinv);
else
{
udiv_qrnnd (q, r1, nx, workaround << GMP_NAIL_BITS,
dx << GMP_NAIL_BITS);
r1 >>= GMP_NAIL_BITS;
}
}
umul_ppmm (p1, p0, d1, q << GMP_NAIL_BITS);
p0 >>= GMP_NAIL_BITS;
r0 = np[dn - 2];
rx = 0;
if (r1 < p1 || (r1 == p1 && r0 < p0))
{
p1 -= p0 < d1;
p0 = (p0 - d1) & GMP_NUMB_MASK;
q--;
r1 = (r1 + dx) & GMP_NUMB_MASK;
rx = r1 < dx;
}
p1 += r0 < p0; /* cannot carry! */
rx -= r1 < p1; /* may become 11..1 if q is still too large */
r1 = (r1 - p1) & GMP_NUMB_MASK;
r0 = (r0 - p0) & GMP_NUMB_MASK;
cy_limb = mpn_submul_1 (np, dp, dn - 2, q);
/* Check if we've over-estimated q, and adjust as needed. */
{
mp_limb_t cy1, cy2;
cy1 = r0 < cy_limb;
r0 = (r0 - cy_limb) & GMP_NUMB_MASK;
cy2 = r1 < cy1;
r1 -= cy1;
np[dn - 1] = r1;
np[dn - 2] = r0;
if (cy2 != rx)
{
mpn_add_n (np, np, dp, dn);
q--;
}
}
qp[i] = q;
}
}
/* ______ ______ ______
|__rx__|__r1__|__r0__| partial remainder
______ ______
- |__p1__|__p0__| partial product to subtract
______ ______
- |______|cylimb|
rx is -1, 0 or 1. If rx=1, then q is correct (it should match
carry out). If rx=-1 then q is too large. If rx=0, then q might
be too large, but it is most likely correct.
*/
return most_significant_q_limb;
}
void
mpn_tdiv_q (mp_ptr qp,
mp_srcptr np, mp_size_t nn,
mp_srcptr dp, mp_size_t dn)
{
mp_ptr new_dp, new_np, tp, rp, scratch;
mp_limb_t cy, dh, qh;
mp_size_t new_nn, qn;
mp_limb_t dinv;
int cnt;
TMP_DECL;
TMP_MARK;
ASSERT (nn >= dn);
ASSERT (dn > 0);
ASSERT (dp[dn - 1] != 0);
ASSERT (! MPN_OVERLAP_P (qp, nn - dn + 1, np, nn));
ASSERT (! MPN_OVERLAP_P (qp, nn - dn + 1, dp, dn));
ASSERT_ALWAYS (FUDGE >= 2);
if (dn == 1)
{
mpn_divrem_1 (qp, 0L, np, nn, dp[dn - 1]);
return;
}
scratch = TMP_ALLOC_LIMBS(nn + 1);
qn = nn - dn + 1; /* Quotient size, high limb might be zero */
if (qn + FUDGE >= dn)
{
/* |________________________|
|_______| */
new_np = scratch;
dh = dp[dn - 1];
if (LIKELY ((dh & GMP_NUMB_HIGHBIT) == 0))
{
count_leading_zeros (cnt, dh);
cy = mpn_lshift (new_np, np, nn, cnt);
new_np[nn] = cy;
new_nn = nn + (cy != 0);
new_dp = TMP_ALLOC_LIMBS (dn);
mpn_lshift (new_dp, dp, dn, cnt);
if (dn == 2)
{
qh = mpn_divrem_2 (qp, 0L, new_np, new_nn, new_dp);
}
else if (BELOW_THRESHOLD (dn, DC_DIV_Q_THRESHOLD) ||
BELOW_THRESHOLD (new_nn - dn, DC_DIV_Q_THRESHOLD))
{
invert_1(dinv, new_dp[dn - 1], new_dp[dn - 2]);
qh = mpn_sb_div_q (qp, new_np, new_nn, new_dp, dn, dinv);
}
else if (BELOW_THRESHOLD (dn, INV_DIV_Q_THRESHOLD) ||
BELOW_THRESHOLD (nn, 2 * INV_DIV_Q_THRESHOLD))
{
invert_1(dinv, new_dp[dn - 1], new_dp[dn - 2]);
qh = mpn_dc_div_q (qp, new_np, new_nn, new_dp, dn, dinv);
}
else
{
mp_ptr inv = TMP_ALLOC_LIMBS(dn);
mpn_invert(inv, new_dp, dn);
qh = mpn_inv_div_q (qp, new_np, new_nn, new_dp, dn, inv);
}
if (cy == 0)
qp[qn - 1] = qh;
else if (UNLIKELY (qh != 0))
{
/* This happens only when the quotient is close to B^n and
mpn_*_divappr_q returned B^n. */
mp_size_t i, n;
n = new_nn - dn;
for (i = 0; i < n; i++)
qp[i] = GMP_NUMB_MAX;
qh = 0; /* currently ignored */
}
}
else /* divisor is already normalised */
{
if (new_np != np)
MPN_COPY (new_np, np, nn);
if (dn == 2)
{
qh = mpn_divrem_2 (qp, 0L, new_np, nn, dp);
}
else if (BELOW_THRESHOLD (dn, DC_DIV_Q_THRESHOLD) ||
BELOW_THRESHOLD (nn - dn, DC_DIV_Q_THRESHOLD))
{
invert_1(dinv, dh, dp[dn - 2]);
qh = mpn_sb_div_q (qp, new_np, nn, dp, dn, dinv);
}
else if (BELOW_THRESHOLD (dn, INV_DIV_Q_THRESHOLD) ||
BELOW_THRESHOLD (nn, 2 * INV_DIV_Q_THRESHOLD))
{
invert_1(dinv, dh, dp[dn - 2]);
qh = mpn_dc_div_q (qp, new_np, nn, dp, dn, dinv);
}
else
{
mp_ptr inv = TMP_ALLOC_LIMBS(dn);
mpn_invert(inv, dp, dn);
qh = mpn_inv_div_q (qp, new_np, nn, dp, dn, inv);
}
qp[nn - dn] = qh;
}
}
else
{
/* |________________________|
|_________________| */
tp = TMP_ALLOC_LIMBS (qn + 1);
new_np = scratch;
new_nn = 2 * qn + 1;
if (new_np == np)
/* We need {np,nn} to remain untouched until the final adjustment, so
we need to allocate separate space for new_np. */
new_np = TMP_ALLOC_LIMBS (new_nn + 1);
dh = dp[dn - 1];
if (LIKELY ((dh & GMP_NUMB_HIGHBIT) == 0))
{
count_leading_zeros (cnt, dh);
cy = mpn_lshift (new_np, np + nn - new_nn, new_nn, cnt);
new_np[new_nn] = cy;
new_nn += (cy != 0);
new_dp = TMP_ALLOC_LIMBS (qn + 1);
mpn_lshift (new_dp, dp + dn - (qn + 1), qn + 1, cnt);
new_dp[0] |= dp[dn - (qn + 1) - 1] >> (GMP_NUMB_BITS - cnt);
if (qn + 1 == 2)
{
qh = mpn_divrem_2 (tp, 0L, new_np, new_nn, new_dp);
}
else if (BELOW_THRESHOLD (qn - 1, DC_DIVAPPR_Q_THRESHOLD))
{
invert_1(dinv, new_dp[qn], new_dp[qn - 1]);
qh = mpn_sb_divappr_q (tp, new_np, new_nn, new_dp, qn + 1, dinv);
}
else if (BELOW_THRESHOLD (qn - 1, INV_DIVAPPR_Q_THRESHOLD))
{
invert_1(dinv, new_dp[qn], new_dp[qn - 1]);
qh = mpn_dc_divappr_q (tp, new_np, new_nn, new_dp, qn + 1, dinv);
}
else
{
mp_ptr inv = TMP_ALLOC_LIMBS(qn + 1);
mpn_invert(inv, new_dp, qn + 1);
qh = mpn_inv_divappr_q (tp, new_np, new_nn, new_dp, qn + 1, inv);
}
if (cy == 0)
tp[qn] = qh;
else if (UNLIKELY (qh != 0))
{
/* This happens only when the quotient is close to B^n and
mpn_*_divappr_q returned B^n. */
mp_size_t i, n;
n = new_nn - (qn + 1);
for (i = 0; i < n; i++)
tp[i] = GMP_NUMB_MAX;
qh = 0; /* currently ignored */
}
}
else /* divisor is already normalised */
{
mp_limb_t
mpn_div_qr_1n_pi2 (mp_ptr qp,
mp_srcptr up, mp_size_t un,
struct precomp_div_1_pi2 *pd)
{
mp_limb_t most_significant_q_limb;
mp_size_t i;
mp_limb_t r, u2, u1, u0;
mp_limb_t d0, di1, di0;
mp_limb_t q3a, q2a, q2b, q1b, q2c, q1c, q1d, q0d;
mp_limb_t cnd;
ASSERT (un >= 2);
ASSERT ((pd->d & GMP_NUMB_HIGHBIT) != 0);
ASSERT (! MPN_OVERLAP_P (qp, un-2, up, un) || qp+2 >= up);
ASSERT_MPN (up, un);
#define q3 q3a
#define q2 q2b
#define q1 q1b
up += un - 3;
r = up[2];
d0 = pd->d;
most_significant_q_limb = (r >= d0);
r -= d0 & -most_significant_q_limb;
qp += un - 3;
qp[2] = most_significant_q_limb;
di1 = pd->dip[1];
di0 = pd->dip[0];
for (i = un - 3; i >= 0; i -= 2)
{
u2 = r;
u1 = up[1];
u0 = up[0];
/* Dividend in {r,u1,u0} */
umul_ppmm (q1d,q0d, u1, di0);
umul_ppmm (q2b,q1b, u1, di1);
q2b++; /* cannot spill */
add_sssaaaa (r,q2b,q1b, q2b,q1b, u1,u0);
umul_ppmm (q2c,q1c, u2, di0);
add_sssaaaa (r,q2b,q1b, q2b,q1b, q2c,q1c);
umul_ppmm (q3a,q2a, u2, di1);
add_sssaaaa (r,q2b,q1b, q2b,q1b, q2a,q1d);
q3 += r;
r = u0 - q2 * d0;
cnd = (r >= q1);
r += d0 & -cnd;
sub_ddmmss (q3,q2, q3,q2, 0,cnd);
if (UNLIKELY (r >= d0))
{
r -= d0;
add_ssaaaa (q3,q2, q3,q2, 0,1);
}
qp[0] = q2;
qp[1] = q3;
up -= 2;
qp -= 2;
}
if ((un & 1) == 0)
{
u2 = r;
u1 = up[1];
udiv_qrnnd_preinv (q3, r, u2, u1, d0, di1);
qp[1] = q3;
}
return r;
#undef q3
#undef q2
#undef q1
}
/* (rp, 2n) = (xp, n)*(yp, n) */
static void
mpn_mulshort_n(mp_ptr rp, mp_srcptr xp, mp_srcptr yp, mp_size_t n)
{
mp_size_t m;
mp_limb_t t;
mp_ptr rpn2;
ASSERT(n >= 1);
ASSERT_MPN(xp, n);
ASSERT_MPN(yp, n);
ASSERT(!MPN_OVERLAP_P (rp, 2 * n, xp, n));
ASSERT(!MPN_OVERLAP_P (rp, 2 * n, yp, n));
if (BELOW_THRESHOLD(n, MULHIGH_BASECASE_THRESHOLD))
{
mpn_mul_basecase(rp, xp, n, yp, n);
return;
}
if (BELOW_THRESHOLD (n, MULHIGH_DC_THRESHOLD))
{
mpn_mulshort_n_basecase(rp, xp, yp, n);
return;
}
/* choose optimal m s.t. n + 2 <= 2m, m < n */
ASSERT (n >= 4);
m = 87 * n / 128;
if (2 * m < n + 2)
m = (n + 1) / 2 + 1;
if (m >= n)
m = n - 1;
ASSERT (n + 2 <= 2 * m);
ASSERT (m < n);
rpn2 = rp + n - 2;
mpn_mul_n (rp + n - m + n - m, xp + n - m, yp + n - m, m);
mpn_mulshort_n (rp, xp, yp + m, n - m);
ASSERT_NOCARRY (mpn_add (rpn2, rpn2, n + 2, rpn2 - m, n - m + 2));
mpn_mulshort_n (rp, xp + m, yp, n - m);
ASSERT_NOCARRY (mpn_add (rpn2, rpn2, n + 2, rpn2 - m, n - m + 2));
umul_ppmm (rp[1], t, xp[m - 1], yp[n - m - 1] << GMP_NAIL_BITS);
rp[0] = t >> GMP_NAIL_BITS;
ASSERT_NOCARRY (mpn_add (rpn2, rpn2, n + 2, rp, 2));
umul_ppmm (rp[1], t, xp[n - m - 1], yp[m - 1] << GMP_NAIL_BITS);
rp[0] = t >> GMP_NAIL_BITS;
ASSERT_NOCARRY (mpn_add (rpn2, rpn2, n + 2, rp, 2));
return;
}
void
mpn_mul_basecase (mp_ptr rp,
mp_srcptr up, mp_size_t un,
mp_srcptr vp, mp_size_t vn)
{
ASSERT (un >= vn);
ASSERT (vn >= 1);
ASSERT (! MPN_OVERLAP_P (rp, un+vn, up, un));
ASSERT (! MPN_OVERLAP_P (rp, un+vn, vp, vn));
/* We first multiply by the low order limb (or depending on optional function
availability, limbs). This result can be stored, not added, to rp. We
also avoid a loop for zeroing this way. */
#if HAVE_NATIVE_mpn_mul_2
if (vn >= 2)
{
rp[un + 1] = mpn_mul_2 (rp, up, un, vp);
rp += 2, vp += 2, vn -= 2;
}
else
{
rp[un] = mpn_mul_1 (rp, up, un, vp[0]);
return;
}
#else
rp[un] = mpn_mul_1 (rp, up, un, vp[0]);
rp += 1, vp += 1, vn -= 1;
#endif
/* Now accumulate the product of up[] and the next low-order limb (or
depending on optional function availability, limbs) from vp[0]. */
#define MAX_LEFT MP_SIZE_T_MAX
#if HAVE_NATIVE_mpn_addmul_4
while (vn >= 4)
{
rp[un + 4 - 1] = mpn_addmul_4 (rp, up, un, vp);
rp += 4, vp += 4, vn -= 4;
}
#undef MAX_LEFT
#define MAX_LEFT 3
#endif
#if HAVE_NATIVE_mpn_addmul_3
while (vn >= 3)
{
rp[un + 3 - 1] = mpn_addmul_3 (rp, up, un, vp);
rp += 3, vp += 3, vn -= 3;
if (MAX_LEFT - 3 <= 3)
break;
}
#undef MAX_LEFT
#define MAX_LEFT 2
#endif
#if HAVE_NATIVE_mpn_addmul_2
while (vn >= 2)
{
rp[un + 2 - 1] = mpn_addmul_2 (rp, up, un, vp);
rp += 2, vp += 2, vn -= 2;
if (MAX_LEFT - 2 <= 2)
break;
}
#undef MAX_LEFT
#define MAX_LEFT 1
#endif
while (vn >= 1)
{
rp[un] = mpn_addmul_1 (rp, up, un, vp[0]);
rp += 1, vp += 1, vn -= 1;
if (MAX_LEFT - 1 <= 1)
break;
}
}
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];
}
mp_limb_t
mpn_bdivmod (mp_ptr qp, mp_ptr up, mp_size_t usize,
mp_srcptr vp, mp_size_t vsize, unsigned long int d)
{
mp_limb_t v_inv;
ASSERT (usize >= 1);
ASSERT (vsize >= 1);
ASSERT (usize * GMP_NUMB_BITS >= d);
ASSERT (! MPN_OVERLAP_P (up, usize, vp, vsize));
ASSERT (! MPN_OVERLAP_P (qp, d/GMP_NUMB_BITS, vp, vsize));
ASSERT (MPN_SAME_OR_INCR2_P (qp, d/GMP_NUMB_BITS, up, usize));
ASSERT_MPN (up, usize);
ASSERT_MPN (vp, vsize);
/* 1/V mod 2^GMP_NUMB_BITS. */
binvert_limb (v_inv, vp[0]);
/* Fast code for two cases previously used by the accel part of mpn_gcd.
(Could probably remove this now it's inlined there.) */
if (usize == 2 && vsize == 2 &&
(d == GMP_NUMB_BITS || d == 2*GMP_NUMB_BITS))
{
mp_limb_t hi, lo;
mp_limb_t q = (up[0] * v_inv) & GMP_NUMB_MASK;
umul_ppmm (hi, lo, q, vp[0] << GMP_NAIL_BITS);
up[0] = 0;
up[1] -= hi + q*vp[1];
qp[0] = q;
if (d == 2*GMP_NUMB_BITS)
{
q = (up[1] * v_inv) & GMP_NUMB_MASK;
up[1] = 0;
qp[1] = q;
}
return 0;
}
/* Main loop. */
while (d >= GMP_NUMB_BITS)
{
mp_limb_t q = (up[0] * v_inv) & GMP_NUMB_MASK;
mp_limb_t b = mpn_submul_1 (up, vp, MIN (usize, vsize), q);
if (usize > vsize)
mpn_sub_1 (up + vsize, up + vsize, usize - vsize, b);
d -= GMP_NUMB_BITS;
up += 1, usize -= 1;
*qp++ = q;
}
if (d)
{
mp_limb_t b;
mp_limb_t q = (up[0] * v_inv) & (((mp_limb_t)1<<d) - 1);
if (q <= 1)
{
if (q == 0)
return 0;
else
b = mpn_sub_n (up, up, vp, MIN (usize, vsize));
}
else
b = mpn_submul_1 (up, vp, MIN (usize, vsize), q);
if (usize > vsize)
mpn_sub_1 (up + vsize, up + vsize, usize - vsize, b);
return q;
}
return 0;
}
/* (rp, 2n) = (xp, n)*(yp, n) / B^n */
inline static void
mpn_mulshort_n_basecase(mp_ptr rp, mp_srcptr xp, mp_srcptr yp, mp_size_t n)
{
mp_size_t i, k;
ASSERT(n >= 3); /* this restriction doesn't make a lot of sense in general */
ASSERT_MPN(xp, n);
ASSERT_MPN(yp, n);
ASSERT(!MPN_OVERLAP_P (rp, 2 * n, xp, n));
ASSERT(!MPN_OVERLAP_P (rp, 2 * n, yp, n));
k = n - 2; /* so want short product sum_(i + j >= k) x[i]y[j]B^(i + j) */
i = 0;
/* Multiply w limbs from y + i to (2 + i + w - 1) limbs from x + (n - 2 - i - w + 1)
and put it into r + (n - 2 - w + 1), "overflow" (i.e. last) limb into
r + (n + w - 1) for i between 0 and n - 2.
i == n - w needs special treatment. */
/* We first multiply by the low order limb (or depending on optional function
availability, limbs). This result can be stored, not added, to rp. We
also avoid a loop for zeroing this way. */
#if HAVE_NATIVE_mpn_mul_2
rp[n + 1] = mpn_mul_2 (rp + k - 1, xp + k - 1, 2 + 1, yp);
i += 2;
#else
rp[n] = mpn_mul_1 (rp + k, xp + k, 2, yp[0]);
i += 1;
#endif
#if HAVE_NATIVE_mpn_addmul_6
while (i < n - 6)
{
rp[n + i + 6 - 1] = mpn_addmul_6 (rp + k - 6 + 1, xp + k - i - 6 + 1, 2 + i + 6 - 1, yp + i);
i += 6;
}
if (i == n - 6)
{
rp[n + n - 1] = mpn_addmul_6 (rp + i, xp, n, yp + i);
return;
}
#endif
#if HAVE_NATIVE_mpn_addmul_5
while (i < n - 5)
{
rp[n + i + 5 - 1] = mpn_addmul_5 (rp + k - 5 + 1, xp + k - i - 5 + 1, 2 + i + 5 - 1, yp + i)
i += 5;
}
if (i == n - 5)
{
rp[n + n - 1] = mpn_addmul_5 (rp + i, xp, n, yp + i);
return;
}
#endif
#if HAVE_NATIVE_mpn_addmul_4
while (i < n - 4)
{
rp[n + i + 4 - 1] = mpn_addmul_4 (rp + k - 4 + 1, xp + k - i - 4 + 1, 2 + i + 4 - 1, yp + i);
i += 4;
}
if (i == n - 4)
{
rp[n + n - 1] = mpn_addmul_4 (rp + i, xp, n, yp + i);
return;
}
#endif
#if HAVE_NATIVE_mpn_addmul_3
while (i < n - 3)
{
rp[n + i + 3 - 1] = mpn_addmul_3 (rp + k - 3 + 1, xp + k - i - 3 + 1, 2 + i + 3 - 1, yp + i);
i += 3;
}
if (i == n - 3)
{
rp[n + n - 1] = mpn_addmul_3 (rp + i, xp, n, yp + i);
return;
}
#endif
#if HAVE_NATIVE_mpn_addmul_2
while (i < n - 2)
{
rp[n + i + 2 - 1] = mpn_addmul_2 (rp + k - 2 + 1, xp + k - i - 2 + 1, 2 + i + 2 - 1, yp + i);
i += 2;
}
if (i == n - 2)
{
rp[n + n - 1] = mpn_addmul_2 (rp + i, xp, n, yp + i);
return;
}
#endif
while (i < n - 1)
{
rp[n + i] = mpn_addmul_1 (rp + k, xp + k - i, 2 + i, yp[i]);
i += 1;
}
rp[n + n - 1] = mpn_addmul_1 (rp + i, xp, n, yp[i]);
return;
}
/*
Computes {np, n} / {dp, n} mod B^n, using divide-and-conquer
algorithm, switching to classical for n <= BDIV_Q_DC_THRESHOLD.
Also computes a 2 limb "overflow". See sb_bdiv_q.c for a definition.
scratch is workspace.
*/
void
mpn_dc_bdiv_q_n (mp_ptr qp, mp_ptr wp, mp_ptr np, mp_srcptr dp,
mp_size_t n, mp_limb_t dinv, mp_ptr scratch)
{
mp_size_t s, t;
mp_limb_t cy;
ASSERT (n >= 6);
ASSERT (! MPN_OVERLAP_P (qp, n, np, n));
ASSERT (! MPN_OVERLAP_P (qp, n, dp, n));
ASSERT (! MPN_OVERLAP_P (wp, 2, np, n));
ASSERT (! MPN_OVERLAP_P (wp, 2, dp, n));
ASSERT (! MPN_OVERLAP_P (np, n, dp, n));
/*
Example with s = 4, t = 3, n = 7:
C
C C
C C C
qp . A B B B
. A A B B B
1 A A A B B B
0 A A A A B B B
0 1 ...
dp
*/
t = n / 2; /* t = floor(n/2) */
s = n - t; /* s = ceil(n/2) */
/* recurse into low half of quotient (region A) */
if (s <= DC_BDIV_Q_THRESHOLD)
mpn_sb_bdiv_q (qp, wp, np, s, dp, s, dinv);
else
mpn_dc_bdiv_q_n (qp, wp, np, dp, s, dinv, scratch);
/* remove region B and overflow from A from N
(if n odd, do first row of B separately --- we could have used
mpn_mulmid, but this saves some logic) */
mpn_mulmid_n (scratch, dp + 1, qp + (n & 1), t);
if (n & 1)
{
cy = mpn_addmul_1 (scratch, dp + s, t, qp[0]);
MPN_INCR_U (scratch + t, 2, cy);
}
ADDC_LIMB (cy, scratch[0], scratch[0], wp[0]); /* overflow from A */
MPN_INCR_U (scratch + 1, t + 1, wp[1] + cy);
cy = mpn_sub_n (np + s, np + s, scratch, t);
MPN_INCR_U (scratch + t, 2, cy);
/* recurse into top half of quotient (region C)
(this does not overwrite {scratch + t, 2}, because n >= 6 implies
t >= 3 implies floor(t/2) + 2 <= t) */
if (t <= DC_BDIV_Q_THRESHOLD)
mpn_sb_bdiv_q (qp + s, wp, np + s, t, dp, t, dinv);
else
mpn_dc_bdiv_q_n (qp + s, wp, np + s, dp, t, dinv, scratch);
/* combine overflows from B and C */
ADDC_LIMB (cy, wp[0], wp[0], scratch[t]);
wp[1] += scratch[t + 1] + cy;
}
mp_limb_t
mpn_divrem (mp_ptr qp, mp_size_t qxn,
mp_ptr np, mp_size_t nn,
mp_srcptr dp, mp_size_t dn)
{
ASSERT (qxn >= 0);
ASSERT (nn >= dn);
ASSERT (dn >= 1);
ASSERT (dp[dn-1] & GMP_NUMB_HIGHBIT);
ASSERT (! MPN_OVERLAP_P (np, nn, dp, dn));
ASSERT (! MPN_OVERLAP_P (qp, nn-dn+qxn, np, nn) || qp==np+dn+qxn);
ASSERT (! MPN_OVERLAP_P (qp, nn-dn+qxn, dp, dn));
ASSERT_MPN (np, nn);
ASSERT_MPN (dp, dn);
if (dn == 1)
{
mp_limb_t ret;
mp_ptr q2p;
mp_size_t qn;
TMP_DECL;
TMP_MARK;
q2p = (mp_ptr) TMP_ALLOC ((nn + qxn) * BYTES_PER_MP_LIMB);
np[0] = mpn_divrem_1 (q2p, qxn, np, nn, dp[0]);
qn = nn + qxn - 1;
MPN_COPY (qp, q2p, qn);
ret = q2p[qn];
TMP_FREE;
return ret;
}
else if (dn == 2)
{
return mpn_divrem_2 (qp, qxn, np, nn, dp);
}
else
{
mp_ptr rp, q2p;
mp_limb_t qhl;
mp_size_t qn;
TMP_DECL;
TMP_MARK;
if (UNLIKELY (qxn != 0))
{
mp_ptr n2p;
n2p = (mp_ptr) TMP_ALLOC ((nn + qxn) * BYTES_PER_MP_LIMB);
MPN_ZERO (n2p, qxn);
MPN_COPY (n2p + qxn, np, nn);
q2p = (mp_ptr) TMP_ALLOC ((nn - dn + qxn + 1) * BYTES_PER_MP_LIMB);
rp = (mp_ptr) TMP_ALLOC (dn * BYTES_PER_MP_LIMB);
mpn_tdiv_qr (q2p, rp, 0L, n2p, nn + qxn, dp, dn);
MPN_COPY (np, rp, dn);
qn = nn - dn + qxn;
MPN_COPY (qp, q2p, qn);
qhl = q2p[qn];
}
else
{
q2p = (mp_ptr) TMP_ALLOC ((nn - dn + 1) * BYTES_PER_MP_LIMB);
rp = (mp_ptr) TMP_ALLOC (dn * BYTES_PER_MP_LIMB);
mpn_tdiv_qr (q2p, rp, 0L, np, nn, dp, dn);
MPN_COPY (np, rp, dn); /* overwrite np area with remainder */
qn = nn - dn;
MPN_COPY (qp, q2p, qn);
qhl = q2p[qn];
}
TMP_FREE;
return qhl;
}
}
void
mpn_sqr (mp_ptr p, mp_srcptr a, mp_size_t n)
{
ASSERT (n >= 1);
ASSERT (! MPN_OVERLAP_P (p, 2 * n, a, n));
if (BELOW_THRESHOLD (n, SQR_BASECASE_THRESHOLD))
{ /* mul_basecase is faster than sqr_basecase on small sizes sometimes */
mpn_mul_basecase (p, a, n, a, n);
}
else if (BELOW_THRESHOLD (n, SQR_TOOM2_THRESHOLD))
{
mpn_sqr_basecase (p, a, n);
}
else if (BELOW_THRESHOLD (n, SQR_TOOM3_THRESHOLD))
{
/* Allocate workspace of fixed size on stack: fast! */
mp_limb_t ws[mpn_toom2_sqr_itch (SQR_TOOM3_THRESHOLD_LIMIT-1)];
ASSERT (SQR_TOOM3_THRESHOLD <= SQR_TOOM3_THRESHOLD_LIMIT);
mpn_toom2_sqr (p, a, n, ws);
}
else if (BELOW_THRESHOLD (n, SQR_TOOM4_THRESHOLD))
{
mp_ptr ws;
TMP_SDECL;
TMP_SMARK;
ws = TMP_SALLOC_LIMBS (mpn_toom3_sqr_itch (n));
mpn_toom3_sqr (p, a, n, ws);
TMP_SFREE;
}
else if (BELOW_THRESHOLD (n, SQR_TOOM6_THRESHOLD))
{
mp_ptr ws;
TMP_SDECL;
TMP_SMARK;
ws = TMP_SALLOC_LIMBS (mpn_toom4_sqr_itch (n));
mpn_toom4_sqr (p, a, n, ws);
TMP_SFREE;
}
else if (BELOW_THRESHOLD (n, SQR_TOOM8_THRESHOLD))
{
mp_ptr ws;
TMP_SDECL;
TMP_SMARK;
ws = TMP_SALLOC_LIMBS (mpn_toom6_sqr_itch (n));
mpn_toom6_sqr (p, a, n, ws);
TMP_SFREE;
}
else if (BELOW_THRESHOLD (n, SQR_FFT_THRESHOLD))
{
mp_ptr ws;
TMP_DECL;
TMP_MARK;
ws = TMP_ALLOC_LIMBS (mpn_toom8_sqr_itch (n));
mpn_toom8_sqr (p, a, n, ws);
TMP_FREE;
}
else
{
/* The current FFT code allocates its own space. That should probably
change. */
mpn_fft_mul (p, a, n, a, n);
}
}
/*
ret + (xp, n) = (yp, n)*(zp, n) % 2^b + 1
needs (tp, 2n) temp space, everything reduced mod 2^b
inputs, outputs are fully reduced
N.B: 2n is not the same as 2b rounded up to nearest limb!
*/
inline static int
mpn_mulmod_2expp1_internal (mp_ptr xp, mp_srcptr yp, mp_srcptr zp,
mpir_ui b, mp_ptr tp)
{
mp_size_t n, k;
mp_limb_t c;
TMP_DECL;
n = BITS_TO_LIMBS (b);
k = GMP_NUMB_BITS * n - b;
ASSERT(b > 0);
ASSERT(n > 0);
ASSERT_MPN(yp, n);
ASSERT_MPN(zp, n);
ASSERT(!MPN_OVERLAP_P (tp, 2 * n, yp, n));
ASSERT(!MPN_OVERLAP_P (tp, 2 * n, zp, n));
ASSERT(MPN_SAME_OR_SEPARATE_P (xp, tp, n));
ASSERT(MPN_SAME_OR_SEPARATE_P (xp, tp + n, n));
ASSERT(k == 0 || yp[n - 1] >> (GMP_NUMB_BITS - k) == 0);
ASSERT(k == 0 || zp[n - 1] >> (GMP_NUMB_BITS - k) == 0);
#ifndef TUNE_PROGRAM_BUILD
if (k == 0 && n > FFT_MULMOD_2EXPP1_CUTOFF && n == mpir_fft_adjust_limbs(n))
{
mp_bitcnt_t depth1, depth = 1;
mp_size_t w1, off;
mp_ptr tx, ty, tz;
mp_limb_t ret;
TMP_MARK;
tx = TMP_BALLOC_LIMBS(3*n + 3);
ty = tx + n + 1;
tz = ty + n + 1;
MPN_COPY(ty, yp, n);
MPN_COPY(tz, zp, n);
ty[n] = 0;
tz[n] = 0;
while ((((mp_limb_t)1)<<depth) < b) depth++;
if (depth < 12) off = mulmod_2expp1_table_n[0];
else off = mulmod_2expp1_table_n[MIN(depth, FFT_N_NUM + 11) - 12];
depth1 = depth/2 - off;
w1 = b/(((mp_limb_t)1)<<(2*depth1));
mpir_fft_mulmod_2expp1(tx, ty, tz, n, depth1, w1);
MPN_COPY(xp, tx, n);
ret = tx[n];
TMP_FREE;
return ret;
}
#endif
if (yp == zp)
mpn_sqr(tp, yp, n);
else
mpn_mul_n (tp, yp, zp, n);
if (k == 0)
{
c = mpn_sub_n (xp, tp, tp + n, n);
return mpn_add_1 (xp, xp, n, c);
}
c = tp[n - 1];
tp[n - 1] &= GMP_NUMB_MASK >> k;
#if HAVE_NATIVE_mpn_sublsh_nc
c = mpn_sublsh_nc (xp, tp, tp + n, n, k, c);
#else
{
mp_limb_t c1;
c1 = mpn_lshift (tp + n, tp + n, n, k);
tp[n] |= c >> (GMP_NUMB_BITS - k);
c = mpn_sub_n (xp, tp, tp + n, n) + c1;
}
#endif
c = mpn_add_1 (xp, xp, n, c);
xp[n - 1] &= GMP_NUMB_MASK >> k;
return c;
}
void
mpn_mul_basecase (mp_ptr rp,
mp_srcptr up, mp_size_t un,
mp_srcptr vp, mp_size_t vn)
{
ASSERT (un >= vn);
ASSERT (vn >= 1);
ASSERT (! MPN_OVERLAP_P (rp, un+vn, up, un));
ASSERT (! MPN_OVERLAP_P (rp, un+vn, vp, vn));
/* We first multiply by the low order limb (or depending on optional function
availability, limbs). This result can be stored, not added, to rp. We
also avoid a loop for zeroing this way. */
#ifdef HAVE_NATIVE_mpn_mul_2
if (vn >= 2)
{
rp[un + 1] = mpn_mul_2 (rp, up, un, vp);
rp += 2, vp += 2, vn -= 2;
}
else
{
rp[un] = mpn_mul_1 (rp, up, un, vp[0]);
return;
}
#else
rp[un] = mpn_mul_1 (rp, up, un, vp[0]);
rp += 1, vp += 1, vn -= 1;
#endif
/* Now accumulate the product of up[] and the next higher limb (or depending
on optional function availability, limbs) from vp[]. */
#define MAX_LEFT MP_SIZE_T_MAX /* Used to simplify loops into if statements */
#ifdef HAVE_NATIVE_mpn_addmul_6
while (vn >= 6)
{
rp[un + 6 - 1] = mpn_addmul_6 (rp, up, un, vp);
if (MAX_LEFT == 6)
return;
rp += 6, vp += 6, vn -= 6;
if (MAX_LEFT < 2 * 6)
break;
}
#undef MAX_LEFT
#define MAX_LEFT (6 - 1)
#endif
#ifdef HAVE_NATIVE_mpn_addmul_5
while (vn >= 5)
{
rp[un + 5 - 1] = mpn_addmul_5 (rp, up, un, vp);
if (MAX_LEFT == 5)
return;
rp += 5, vp += 5, vn -= 5;
if (MAX_LEFT < 2 * 5)
break;
}
#undef MAX_LEFT
#define MAX_LEFT (5 - 1)
#endif
#ifdef HAVE_NATIVE_mpn_addmul_4
while (vn >= 4)
{
rp[un + 4 - 1] = mpn_addmul_4 (rp, up, un, vp);
if (MAX_LEFT == 4)
return;
rp += 4, vp += 4, vn -= 4;
if (MAX_LEFT < 2 * 4)
break;
}
#undef MAX_LEFT
#define MAX_LEFT (4 - 1)
#endif
#ifdef HAVE_NATIVE_mpn_addmul_3
while (vn >= 3)
{
rp[un + 3 - 1] = mpn_addmul_3 (rp, up, un, vp);
if (MAX_LEFT == 3)
return;
rp += 3, vp += 3, vn -= 3;
if (MAX_LEFT < 2 * 3)
break;
}
#undef MAX_LEFT
#define MAX_LEFT (3 - 1)
#endif
#ifdef HAVE_NATIVE_mpn_addmul_2
while (vn >= 2)
{
rp[un + 2 - 1] = mpn_addmul_2 (rp, up, un, vp);
if (MAX_LEFT == 2)
return;
rp += 2, vp += 2, vn -= 2;
if (MAX_LEFT < 2 * 2)
break;
}
#undef MAX_LEFT
#define MAX_LEFT (2 - 1)
#endif
while (vn >= 1)
{
rp[un] = mpn_addmul_1 (rp, up, un, vp[0]);
if (MAX_LEFT == 1)
return;
rp += 1, vp += 1, vn -= 1;
}
}
