static void
randiset_lc (gmp_randstate_ptr dst, gmp_randstate_srcptr src)
{
gmp_rand_lc_struct *dstp, *srcp;
srcp = (gmp_rand_lc_struct *) RNG_STATE (src);
dstp = (*__gmp_allocate_func) (sizeof (gmp_rand_lc_struct));
RNG_STATE (dst) = (void *) dstp;
RNG_FNPTR (dst) = (void *) &Linear_Congruential_Generator;
/* _mp_seed and _mp_a might be unnormalized (high zero limbs), but
mpz_init_set won't worry about that */
mpz_init_set (dstp->_mp_seed, srcp->_mp_seed);
mpz_init_set (dstp->_mp_a, srcp->_mp_a);
dstp->_cn = srcp->_cn;
dstp->_cp[0] = srcp->_cp[0];
if (LIMBS_PER_ULONG > 1)
dstp->_cp[1] = srcp->_cp[1];
if (LIMBS_PER_ULONG > 2) /* usually there's only 1 or 2 */
MPN_COPY (dstp->_cp + 2, srcp->_cp + 2, LIMBS_PER_ULONG - 2);
dstp->_mp_m2exp = srcp->_mp_m2exp;
}
void
gmp_randinit_lc_2exp (gmp_randstate_t rstate,
mpz_srcptr a,
unsigned long int c,
mp_bitcnt_t m2exp)
{
gmp_rand_lc_struct *p;
mp_size_t seedn = BITS_TO_LIMBS (m2exp);
ASSERT_ALWAYS (m2exp != 0);
p = __GMP_ALLOCATE_FUNC_TYPE (1, gmp_rand_lc_struct);
RNG_STATE (rstate) = (void *) p;
RNG_FNPTR (rstate) = (void *) &Linear_Congruential_Generator;
/* allocate m2exp bits of space for p->_mp_seed, and initial seed "1" */
mpz_init2 (p->_mp_seed, m2exp);
MPN_ZERO (PTR (p->_mp_seed), seedn);
SIZ (p->_mp_seed) = seedn;
PTR (p->_mp_seed)[0] = 1;
/* "a", forced to 0 to 2^m2exp-1 */
mpz_init (p->_mp_a);
mpz_fdiv_r_2exp (p->_mp_a, a, m2exp);
/* Avoid SIZ(a) == 0 to avoid checking for special case in lc(). */
if (SIZ (p->_mp_a) == 0)
{
SIZ (p->_mp_a) = 1;
PTR (p->_mp_a)[0] = CNST_LIMB (0);
}
MPN_SET_UI (p->_cp, p->_cn, c);
/* Internally we may discard any bits of c above m2exp. The following
code ensures that __GMPN_ADD in lc() will always work. */
if (seedn < p->_cn)
p->_cn = (p->_cp[0] != 0);
p->_mp_m2exp = m2exp;
}
/* Initialize MT-specific data. */
void
gmp_randinit_mt (gmp_randstate_t rstate)
{
__gmp_randinit_mt_noseed (rstate);
RNG_FNPTR (rstate) = (void *) &Mersenne_Twister_Generator;
}
void
gmp_randseed (gmp_randstate_t rstate,
mpz_srcptr seed)
{
(*((gmp_randfnptr_t *) RNG_FNPTR (rstate))->randseed_fn) (rstate, seed);
}
void
gmp_randclear (gmp_randstate_t rstate)
{
(*((gmp_randfnptr_t *) RNG_FNPTR (rstate))->randclear_fn) (rstate);
}
void
gmp_randinit_set (gmp_randstate_ptr dst, gmp_randstate_srcptr src)
{
(*((gmp_randfnptr_t *) RNG_FNPTR (src))->randiset_fn) (dst, src);
}
