int
mpn_divisible_p (mp_srcptr ap, mp_size_t asize,
mp_srcptr dp, mp_size_t dsize)
{
mp_limb_t alow, dlow, dmask;
mp_ptr qp, rp;
mp_size_t i;
TMP_DECL;
ASSERT (asize >= 0);
ASSERT (asize == 0 || ap[asize-1] != 0);
ASSERT (dsize >= 1);
ASSERT (dp[dsize-1] != 0);
ASSERT_MPN (ap, asize);
ASSERT_MPN (dp, dsize);
/* When a<d only a==0 is divisible.
Notice this test covers all cases of asize==0. */
if (asize < dsize)
return (asize == 0);
/* Strip low zero limbs from d, requiring a==0 on those. */
for (;;)
{
alow = *ap;
dlow = *dp;
if (dlow != 0)
break;
if (alow != 0)
return 0; /* a has fewer low zero limbs than d, so not divisible */
/* a!=0 and d!=0 so won't get to size==0 */
asize--; ASSERT (asize >= 1);
dsize--; ASSERT (dsize >= 1);
ap++;
dp++;
}
/* a must have at least as many low zero bits as d */
dmask = LOW_ZEROS_MASK (dlow);
if ((alow & dmask) != 0)
return 0;
if (dsize == 1)
{
if (BELOW_THRESHOLD (asize, MODEXACT_1_ODD_THRESHOLD))
return mpn_mod_1 (ap, asize, dlow) == 0;
if ((dlow & 1) == 0)
{
unsigned twos;
count_trailing_zeros (twos, dlow);
dlow >>= twos;
}
return mpn_modexact_1_odd (ap, asize, dlow) == 0;
}
int
mpz_divisible_ui_p (mpz_srcptr a, unsigned long d)
{
mp_size_t asize;
mp_ptr ap;
unsigned twos;
asize = SIZ(a);
if (UNLIKELY (d == 0))
return (asize == 0);
if (asize == 0) /* 0 divisible by any d */
return 1;
/* For nails don't try to be clever if d is bigger than a limb, just fake
up an mpz_t and go to the main mpz_divisible_p. */
if (d > GMP_NUMB_MAX)
{
mp_limb_t dlimbs[2];
mpz_t dz;
ALLOC(dz) = 2;
PTR(dz) = dlimbs;
mpz_set_ui (dz, d);
return mpz_divisible_p (a, dz);
}
ap = PTR(a);
asize = ABS(asize); /* ignore sign of a */
if (ABOVE_THRESHOLD (asize, BMOD_1_TO_MOD_1_THRESHOLD))
return mpn_mod_1 (ap, asize, (mp_limb_t) d) == 0;
if (! (d & 1))
{
/* Strip low zero bits to get odd d required by modexact. If d==e*2^n
and a is divisible by 2^n and by e, then it's divisible by d. */
if ((ap[0] & LOW_ZEROS_MASK (d)) != 0)
return 0;
count_trailing_zeros (twos, (mp_limb_t) d);
d >>= twos;
}
return mpn_modexact_1_odd (ap, asize, (mp_limb_t) d) == 0;
}
void
check (void)
{
mp_limb_t wp[100], xp[100], yp[100];
mp_size_t size = 100;
refmpn_zero (xp, size);
refmpn_zero (yp, size);
refmpn_zero (wp, size);
pre ("mpn_add_n");
mpn_add_n (wp, xp, yp, size);
post ();
#if HAVE_NATIVE_mpn_add_nc
pre ("mpn_add_nc");
mpn_add_nc (wp, xp, yp, size, CNST_LIMB(0));
post ();
#endif
#if HAVE_NATIVE_mpn_addlsh1_n
pre ("mpn_addlsh1_n");
mpn_addlsh1_n (wp, xp, yp, size);
post ();
#endif
#if HAVE_NATIVE_mpn_and_n
pre ("mpn_and_n");
mpn_and_n (wp, xp, yp, size);
post ();
#endif
#if HAVE_NATIVE_mpn_andn_n
pre ("mpn_andn_n");
mpn_andn_n (wp, xp, yp, size);
post ();
#endif
pre ("mpn_addmul_1");
mpn_addmul_1 (wp, xp, size, yp[0]);
post ();
#if HAVE_NATIVE_mpn_addmul_1c
pre ("mpn_addmul_1c");
mpn_addmul_1c (wp, xp, size, yp[0], CNST_LIMB(0));
post ();
#endif
#if HAVE_NATIVE_mpn_com_n
pre ("mpn_com_n");
mpn_com_n (wp, xp, size);
post ();
#endif
#if HAVE_NATIVE_mpn_copyd
pre ("mpn_copyd");
mpn_copyd (wp, xp, size);
post ();
#endif
#if HAVE_NATIVE_mpn_copyi
pre ("mpn_copyi");
mpn_copyi (wp, xp, size);
post ();
#endif
pre ("mpn_divexact_1");
mpn_divexact_1 (wp, xp, size, CNST_LIMB(123));
post ();
pre ("mpn_divexact_by3c");
mpn_divexact_by3c (wp, xp, size, CNST_LIMB(0));
post ();
pre ("mpn_divrem_1");
mpn_divrem_1 (wp, (mp_size_t) 0, xp, size, CNST_LIMB(123));
post ();
#if HAVE_NATIVE_mpn_divrem_1c
pre ("mpn_divrem_1c");
mpn_divrem_1c (wp, (mp_size_t) 0, xp, size, CNST_LIMB(123), CNST_LIMB(122));
post ();
#endif
pre ("mpn_gcd_1");
xp[0] |= 1;
notdead += (unsigned long) mpn_gcd_1 (xp, size, CNST_LIMB(123));
post ();
#if HAVE_NATIVE_mpn_gcd_finda
pre ("mpn_gcd_finda");
xp[0] |= 1;
xp[1] |= 1;
notdead += mpn_gcd_finda (xp);
post ();
#endif
pre ("mpn_hamdist");
notdead += mpn_hamdist (xp, yp, size);
post ();
#if HAVE_NATIVE_mpn_ior_n
pre ("mpn_ior_n");
mpn_ior_n (wp, xp, yp, size);
post ();
#endif
#if HAVE_NATIVE_mpn_iorn_n
pre ("mpn_iorn_n");
mpn_iorn_n (wp, xp, yp, size);
post ();
#endif
pre ("mpn_lshift");
mpn_lshift (wp, xp, size, 1);
post ();
pre ("mpn_mod_1");
notdead += mpn_mod_1 (xp, size, CNST_LIMB(123));
post ();
#if HAVE_NATIVE_mpn_mod_1c
pre ("mpn_mod_1c");
notdead += mpn_mod_1c (xp, size, CNST_LIMB(123), CNST_LIMB(122));
post ();
#endif
#if GMP_NUMB_BITS % 4 == 0
pre ("mpn_mod_34lsub1");
notdead += mpn_mod_34lsub1 (xp, size);
post ();
#endif
pre ("mpn_modexact_1_odd");
notdead += mpn_modexact_1_odd (xp, size, CNST_LIMB(123));
post ();
pre ("mpn_modexact_1c_odd");
notdead += mpn_modexact_1c_odd (xp, size, CNST_LIMB(123), CNST_LIMB(456));
post ();
pre ("mpn_mul_1");
mpn_mul_1 (wp, xp, size, yp[0]);
post ();
#if HAVE_NATIVE_mpn_mul_1c
pre ("mpn_mul_1c");
mpn_mul_1c (wp, xp, size, yp[0], CNST_LIMB(0));
post ();
#endif
#if HAVE_NATIVE_mpn_mul_2
pre ("mpn_mul_2");
mpn_mul_2 (wp, xp, size-1, yp);
post ();
#endif
pre ("mpn_mul_basecase");
mpn_mul_basecase (wp, xp, (mp_size_t) 3, yp, (mp_size_t) 3);
post ();
#if HAVE_NATIVE_mpn_nand_n
pre ("mpn_nand_n");
mpn_nand_n (wp, xp, yp, size);
post ();
#endif
#if HAVE_NATIVE_mpn_nior_n
pre ("mpn_nior_n");
mpn_nior_n (wp, xp, yp, size);
post ();
#endif
pre ("mpn_popcount");
notdead += mpn_popcount (xp, size);
post ();
pre ("mpn_preinv_mod_1");
notdead += mpn_preinv_mod_1 (xp, size, GMP_NUMB_MAX,
refmpn_invert_limb (GMP_NUMB_MAX));
post ();
#if USE_PREINV_DIVREM_1 || HAVE_NATIVE_mpn_preinv_divrem_1
pre ("mpn_preinv_divrem_1");
mpn_preinv_divrem_1 (wp, (mp_size_t) 0, xp, size, GMP_NUMB_MAX,
refmpn_invert_limb (GMP_NUMB_MAX), 0);
post ();
#endif
#if HAVE_NATIVE_mpn_rsh1add_n
pre ("mpn_rsh1add_n");
mpn_rsh1add_n (wp, xp, yp, size);
post ();
#endif
#if HAVE_NATIVE_mpn_rsh1sub_n
pre ("mpn_rsh1sub_n");
mpn_rsh1sub_n (wp, xp, yp, size);
post ();
#endif
pre ("mpn_rshift");
mpn_rshift (wp, xp, size, 1);
post ();
pre ("mpn_sqr_basecase");
mpn_sqr_basecase (wp, xp, (mp_size_t) 3);
post ();
pre ("mpn_submul_1");
mpn_submul_1 (wp, xp, size, yp[0]);
post ();
#if HAVE_NATIVE_mpn_submul_1c
pre ("mpn_submul_1c");
mpn_submul_1c (wp, xp, size, yp[0], CNST_LIMB(0));
post ();
#endif
pre ("mpn_sub_n");
mpn_sub_n (wp, xp, yp, size);
post ();
#if HAVE_NATIVE_mpn_sub_nc
pre ("mpn_sub_nc");
mpn_sub_nc (wp, xp, yp, size, CNST_LIMB(0));
post ();
#endif
#if HAVE_NATIVE_mpn_sublsh1_n
pre ("mpn_sublsh1_n");
mpn_sublsh1_n (wp, xp, yp, size);
post ();
#endif
#if HAVE_NATIVE_mpn_udiv_qrnnd
pre ("mpn_udiv_qrnnd");
mpn_udiv_qrnnd (&wp[0], CNST_LIMB(122), xp[0], CNST_LIMB(123));
post ();
#endif
#if HAVE_NATIVE_mpn_udiv_qrnnd_r
pre ("mpn_udiv_qrnnd_r");
mpn_udiv_qrnnd (CNST_LIMB(122), xp[0], CNST_LIMB(123), &wp[0]);
post ();
#endif
#if HAVE_NATIVE_mpn_umul_ppmm
pre ("mpn_umul_ppmm");
mpn_umul_ppmm (&wp[0], xp[0], yp[0]);
post ();
#endif
#if HAVE_NATIVE_mpn_umul_ppmm_r
pre ("mpn_umul_ppmm_r");
mpn_umul_ppmm_r (&wp[0], xp[0], yp[0]);
post ();
#endif
#if HAVE_NATIVE_mpn_xor_n
pre ("mpn_xor_n");
mpn_xor_n (wp, xp, yp, size);
post ();
#endif
#if HAVE_NATIVE_mpn_xnor_n
pre ("mpn_xnor_n");
mpn_xnor_n (wp, xp, yp, size);
post ();
#endif
}