/* Called when g is supposed to be gcd(a,b), and g = s a + t b, for some t.
Uses temp1, temp2 and temp3. */
static int
gcdext_valid_p (const mpz_t a, const mpz_t b, const mpz_t g, const mpz_t s)
{
/* It's not clear that gcd(0,0) is well defined, but we allow it and require that
gcd(0,0) = 0. */
if (mpz_sgn (g) < 0)
return 0;
if (mpz_sgn (a) == 0)
{
/* Must have g == abs (b). Any value for s is in some sense "correct",
but it makes sense to require that s == 0. */
return mpz_cmpabs (g, b) == 0 && mpz_sgn (s) == 0;
}
else if (mpz_sgn (b) == 0)
{
/* Must have g == abs (a), s == sign (a) */
return mpz_cmpabs (g, a) == 0 && mpz_cmp_si (s, mpz_sgn (a)) == 0;
}
if (mpz_sgn (g) <= 0)
return 0;
mpz_tdiv_qr (temp1, temp3, a, g);
if (mpz_sgn (temp3) != 0)
return 0;
mpz_tdiv_qr (temp2, temp3, b, g);
if (mpz_sgn (temp3) != 0)
return 0;
/* Require that 2 |s| < |b/g|, or |s| == 1. */
if (mpz_cmpabs_ui (s, 1) > 0)
{
mpz_mul_2exp (temp3, s, 1);
if (mpz_cmpabs (temp3, temp2) >= 0)
return 0;
}
/* Compute the other cofactor. */
mpz_mul(temp2, s, a);
mpz_sub(temp2, g, temp2);
mpz_tdiv_qr(temp2, temp3, temp2, b);
if (mpz_sgn (temp3) != 0)
return 0;
/* Require that 2 |t| < |a/g| or |t| == 1*/
if (mpz_cmpabs_ui (temp2, 1) > 0)
{
mpz_mul_2exp (temp2, temp2, 1);
if (mpz_cmpabs (temp2, temp1) >= 0)
return 0;
}
return 1;
}
int32_t absCompare(const Integer &a, const int64_t b)
{
#if GMP_LIMB_BITS != 64
return absCompare( a, Integer(b));
#else
return mpz_cmpabs_ui( (mpz_srcptr)&(a.gmp_rep), (uint64_t) std::abs(b));
#endif
}
void
check_random (int reps)
{
gmp_randstate_t rands;
mpz_t a, d, r;
int i;
int want;
gmp_randinit_default(rands);
mpz_init (a);
mpz_init (d);
mpz_init (r);
for (i = 0; i < reps; i++)
{
mpz_erandomb (a, rands, 512);
mpz_erandomb_nonzero (d, rands, 512);
mpz_fdiv_r (r, a, d);
want = (mpz_sgn (r) == 0);
check_one (a, d, want);
mpz_sub (a, a, r);
check_one (a, d, 1);
if (mpz_cmpabs_ui (d, 1L) == 0)
continue;
mpz_add_ui (a, a, 1L);
check_one (a, d, 0);
}
mpz_clear (a);
mpz_clear (d);
mpz_clear (r);
gmp_randclear(rands);
}
void
check_random (int reps)
{
gmp_randstate_ptr rands = RANDS;
mpz_t a, d, r;
int i;
int want;
mpz_init (a);
mpz_init (d);
mpz_init (r);
for (i = 0; i < reps; i++)
{
mpz_erandomb (a, rands, 1 << 19);
mpz_erandomb_nonzero (d, rands, 1 << 18);
mpz_fdiv_r (r, a, d);
want = (mpz_sgn (r) == 0);
check_one (a, d, want);
mpz_sub (a, a, r);
check_one (a, d, 1);
if (mpz_cmpabs_ui (d, 1L) == 0)
continue;
mpz_add_ui (a, a, 1L);
check_one (a, d, 0);
}
mpz_clear (a);
mpz_clear (d);
mpz_clear (r);
}
/* Evaluate the expression E and put the result in R. */
void
mpz_eval_expr (mpz_ptr r, expr_t e)
{
mpz_t lhs, rhs;
switch (e->op)
{
case LIT:
mpz_set (r, e->operands.val);
return;
case PLUS:
mpz_init (lhs); mpz_init (rhs);
mpz_eval_expr (lhs, e->operands.ops.lhs);
mpz_eval_expr (rhs, e->operands.ops.rhs);
mpz_add (r, lhs, rhs);
mpz_clear (lhs); mpz_clear (rhs);
return;
case MINUS:
mpz_init (lhs); mpz_init (rhs);
mpz_eval_expr (lhs, e->operands.ops.lhs);
mpz_eval_expr (rhs, e->operands.ops.rhs);
mpz_sub (r, lhs, rhs);
mpz_clear (lhs); mpz_clear (rhs);
return;
case MULT:
mpz_init (lhs); mpz_init (rhs);
mpz_eval_expr (lhs, e->operands.ops.lhs);
mpz_eval_expr (rhs, e->operands.ops.rhs);
mpz_mul (r, lhs, rhs);
mpz_clear (lhs); mpz_clear (rhs);
return;
case DIV:
mpz_init (lhs); mpz_init (rhs);
mpz_eval_expr (lhs, e->operands.ops.lhs);
mpz_eval_expr (rhs, e->operands.ops.rhs);
mpz_fdiv_q (r, lhs, rhs);
mpz_clear (lhs); mpz_clear (rhs);
return;
case MOD:
mpz_init (rhs);
mpz_eval_expr (rhs, e->operands.ops.rhs);
mpz_abs (rhs, rhs);
mpz_eval_mod_expr (r, e->operands.ops.lhs, rhs);
mpz_clear (rhs);
return;
case REM:
/* Check if lhs operand is POW expression and optimize for that case. */
if (e->operands.ops.lhs->op == POW)
{
mpz_t powlhs, powrhs;
mpz_init (powlhs);
mpz_init (powrhs);
mpz_init (rhs);
mpz_eval_expr (powlhs, e->operands.ops.lhs->operands.ops.lhs);
mpz_eval_expr (powrhs, e->operands.ops.lhs->operands.ops.rhs);
mpz_eval_expr (rhs, e->operands.ops.rhs);
mpz_powm (r, powlhs, powrhs, rhs);
if (mpz_cmp_si (rhs, 0L) < 0)
mpz_neg (r, r);
mpz_clear (powlhs);
mpz_clear (powrhs);
mpz_clear (rhs);
return;
}
mpz_init (lhs); mpz_init (rhs);
mpz_eval_expr (lhs, e->operands.ops.lhs);
mpz_eval_expr (rhs, e->operands.ops.rhs);
mpz_fdiv_r (r, lhs, rhs);
mpz_clear (lhs); mpz_clear (rhs);
return;
#if __GNU_MP_VERSION >= 2
case INVMOD:
mpz_init (lhs); mpz_init (rhs);
mpz_eval_expr (lhs, e->operands.ops.lhs);
mpz_eval_expr (rhs, e->operands.ops.rhs);
mpz_invert (r, lhs, rhs);
mpz_clear (lhs); mpz_clear (rhs);
return;
#endif
case POW:
mpz_init (lhs); mpz_init (rhs);
mpz_eval_expr (lhs, e->operands.ops.lhs);
if (mpz_cmpabs_ui (lhs, 1) <= 0)
{
/* For 0^rhs and 1^rhs, we just need to verify that
rhs is well-defined. For (-1)^rhs we need to
determine (rhs mod 2). For simplicity, compute
(rhs mod 2) for all three cases. */
expr_t two, et;
two = malloc (sizeof (struct expr));
two -> op = LIT;
mpz_init_set_ui (two->operands.val, 2L);
makeexp (&et, MOD, e->operands.ops.rhs, two);
e->operands.ops.rhs = et;
}
mpz_eval_expr (rhs, e->operands.ops.rhs);
if (mpz_cmp_si (rhs, 0L) == 0)
/* x^0 is 1 */
mpz_set_ui (r, 1L);
else if (mpz_cmp_si (lhs, 0L) == 0)
/* 0^y (where y != 0) is 0 */
mpz_set_ui (r, 0L);
else if (mpz_cmp_ui (lhs, 1L) == 0)
/* 1^y is 1 */
mpz_set_ui (r, 1L);
else if (mpz_cmp_si (lhs, -1L) == 0)
/* (-1)^y just depends on whether y is even or odd */
mpz_set_si (r, (mpz_get_ui (rhs) & 1) ? -1L : 1L);
else if (mpz_cmp_si (rhs, 0L) < 0)
/* x^(-n) is 0 */
mpz_set_ui (r, 0L);
else
{
unsigned long int cnt;
unsigned long int y;
/* error if exponent does not fit into an unsigned long int. */
if (mpz_cmp_ui (rhs, ~(unsigned long int) 0) > 0)
goto pow_err;
y = mpz_get_ui (rhs);
/* x^y == (x/(2^c))^y * 2^(c*y) */
#if __GNU_MP_VERSION >= 2
cnt = mpz_scan1 (lhs, 0);
#else
cnt = 0;
#endif
if (cnt != 0)
{
if (y * cnt / cnt != y)
goto pow_err;
mpz_tdiv_q_2exp (lhs, lhs, cnt);
mpz_pow_ui (r, lhs, y);
mpz_mul_2exp (r, r, y * cnt);
}
else
mpz_pow_ui (r, lhs, y);
}
mpz_clear (lhs); mpz_clear (rhs);
return;
pow_err:
error = "result of `pow' operator too large";
mpz_clear (lhs); mpz_clear (rhs);
longjmp (errjmpbuf, 1);
case GCD:
mpz_init (lhs); mpz_init (rhs);
mpz_eval_expr (lhs, e->operands.ops.lhs);
mpz_eval_expr (rhs, e->operands.ops.rhs);
mpz_gcd (r, lhs, rhs);
mpz_clear (lhs); mpz_clear (rhs);
return;
#if __GNU_MP_VERSION > 2 || __GNU_MP_VERSION_MINOR >= 1
case LCM:
mpz_init (lhs); mpz_init (rhs);
mpz_eval_expr (lhs, e->operands.ops.lhs);
mpz_eval_expr (rhs, e->operands.ops.rhs);
mpz_lcm (r, lhs, rhs);
mpz_clear (lhs); mpz_clear (rhs);
return;
#endif
case AND:
mpz_init (lhs); mpz_init (rhs);
mpz_eval_expr (lhs, e->operands.ops.lhs);
mpz_eval_expr (rhs, e->operands.ops.rhs);
mpz_and (r, lhs, rhs);
mpz_clear (lhs); mpz_clear (rhs);
return;
case IOR:
mpz_init (lhs); mpz_init (rhs);
mpz_eval_expr (lhs, e->operands.ops.lhs);
mpz_eval_expr (rhs, e->operands.ops.rhs);
mpz_ior (r, lhs, rhs);
mpz_clear (lhs); mpz_clear (rhs);
return;
#if __GNU_MP_VERSION > 2 || __GNU_MP_VERSION_MINOR >= 1
case XOR:
mpz_init (lhs); mpz_init (rhs);
mpz_eval_expr (lhs, e->operands.ops.lhs);
mpz_eval_expr (rhs, e->operands.ops.rhs);
mpz_xor (r, lhs, rhs);
mpz_clear (lhs); mpz_clear (rhs);
return;
#endif
case NEG:
mpz_eval_expr (r, e->operands.ops.lhs);
mpz_neg (r, r);
return;
case NOT:
mpz_eval_expr (r, e->operands.ops.lhs);
mpz_com (r, r);
return;
case SQRT:
mpz_init (lhs);
mpz_eval_expr (lhs, e->operands.ops.lhs);
if (mpz_sgn (lhs) < 0)
{
error = "cannot take square root of negative numbers";
mpz_clear (lhs);
longjmp (errjmpbuf, 1);
}
mpz_sqrt (r, lhs);
return;
#if __GNU_MP_VERSION > 2 || __GNU_MP_VERSION_MINOR >= 1
case ROOT:
mpz_init (lhs); mpz_init (rhs);
mpz_eval_expr (lhs, e->operands.ops.lhs);
mpz_eval_expr (rhs, e->operands.ops.rhs);
if (mpz_sgn (rhs) <= 0)
{
error = "cannot take non-positive root orders";
mpz_clear (lhs); mpz_clear (rhs);
longjmp (errjmpbuf, 1);
}
if (mpz_sgn (lhs) < 0 && (mpz_get_ui (rhs) & 1) == 0)
{
error = "cannot take even root orders of negative numbers";
mpz_clear (lhs); mpz_clear (rhs);
longjmp (errjmpbuf, 1);
}
{
unsigned long int nth = mpz_get_ui (rhs);
if (mpz_cmp_ui (rhs, ~(unsigned long int) 0) > 0)
{
/* If we are asked to take an awfully large root order, cheat and
ask for the largest order we can pass to mpz_root. This saves
some error prone special cases. */
nth = ~(unsigned long int) 0;
}
mpz_root (r, lhs, nth);
}
mpz_clear (lhs); mpz_clear (rhs);
return;
#endif
case FAC:
mpz_eval_expr (r, e->operands.ops.lhs);
if (mpz_size (r) > 1)
{
error = "result of `!' operator too large";
longjmp (errjmpbuf, 1);
}
mpz_fac_ui (r, mpz_get_ui (r));
return;
#if __GNU_MP_VERSION >= 2
case POPCNT:
mpz_eval_expr (r, e->operands.ops.lhs);
{ long int cnt;
cnt = mpz_popcount (r);
mpz_set_si (r, cnt);
}
return;
case HAMDIST:
{ long int cnt;
mpz_init (lhs); mpz_init (rhs);
mpz_eval_expr (lhs, e->operands.ops.lhs);
mpz_eval_expr (rhs, e->operands.ops.rhs);
cnt = mpz_hamdist (lhs, rhs);
mpz_clear (lhs); mpz_clear (rhs);
mpz_set_si (r, cnt);
}
return;
#endif
case LOG2:
mpz_eval_expr (r, e->operands.ops.lhs);
{ unsigned long int cnt;
if (mpz_sgn (r) <= 0)
{
error = "logarithm of non-positive number";
longjmp (errjmpbuf, 1);
}
cnt = mpz_sizeinbase (r, 2);
mpz_set_ui (r, cnt - 1);
}
return;
case LOG:
{ unsigned long int cnt;
mpz_init (lhs); mpz_init (rhs);
mpz_eval_expr (lhs, e->operands.ops.lhs);
mpz_eval_expr (rhs, e->operands.ops.rhs);
if (mpz_sgn (lhs) <= 0)
{
error = "logarithm of non-positive number";
mpz_clear (lhs); mpz_clear (rhs);
longjmp (errjmpbuf, 1);
}
if (mpz_cmp_ui (rhs, 256) >= 0)
{
error = "logarithm base too large";
mpz_clear (lhs); mpz_clear (rhs);
longjmp (errjmpbuf, 1);
}
cnt = mpz_sizeinbase (lhs, mpz_get_ui (rhs));
mpz_set_ui (r, cnt - 1);
mpz_clear (lhs); mpz_clear (rhs);
}
return;
case FERMAT:
{
unsigned long int t;
mpz_init (lhs);
mpz_eval_expr (lhs, e->operands.ops.lhs);
t = (unsigned long int) 1 << mpz_get_ui (lhs);
if (mpz_cmp_ui (lhs, ~(unsigned long int) 0) > 0 || t == 0)
{
error = "too large Mersenne number index";
mpz_clear (lhs);
longjmp (errjmpbuf, 1);
}
mpz_set_ui (r, 1);
mpz_mul_2exp (r, r, t);
mpz_add_ui (r, r, 1);
mpz_clear (lhs);
}
return;
case MERSENNE:
mpz_init (lhs);
mpz_eval_expr (lhs, e->operands.ops.lhs);
if (mpz_cmp_ui (lhs, ~(unsigned long int) 0) > 0)
{
error = "too large Mersenne number index";
mpz_clear (lhs);
longjmp (errjmpbuf, 1);
}
mpz_set_ui (r, 1);
mpz_mul_2exp (r, r, mpz_get_ui (lhs));
mpz_sub_ui (r, r, 1);
mpz_clear (lhs);
return;
case FIBONACCI:
{ mpz_t t;
unsigned long int n, i;
mpz_init (lhs);
mpz_eval_expr (lhs, e->operands.ops.lhs);
if (mpz_sgn (lhs) <= 0 || mpz_cmp_si (lhs, 1000000000) > 0)
{
error = "Fibonacci index out of range";
mpz_clear (lhs);
longjmp (errjmpbuf, 1);
}
n = mpz_get_ui (lhs);
mpz_clear (lhs);
#if __GNU_MP_VERSION > 2 || __GNU_MP_VERSION_MINOR >= 1
mpz_fib_ui (r, n);
#else
mpz_init_set_ui (t, 1);
mpz_set_ui (r, 1);
if (n <= 2)
mpz_set_ui (r, 1);
else
{
for (i = 3; i <= n; i++)
{
mpz_add (t, t, r);
mpz_swap (t, r);
}
}
mpz_clear (t);
#endif
}
return;
case RANDOM:
{
unsigned long int n;
mpz_init (lhs);
mpz_eval_expr (lhs, e->operands.ops.lhs);
if (mpz_sgn (lhs) <= 0 || mpz_cmp_si (lhs, 1000000000) > 0)
{
error = "random number size out of range";
mpz_clear (lhs);
longjmp (errjmpbuf, 1);
}
n = mpz_get_ui (lhs);
mpz_clear (lhs);
mpz_urandomb (r, rstate, n);
}
return;
case NEXTPRIME:
{
mpz_eval_expr (r, e->operands.ops.lhs);
mpz_nextprime (r, r);
}
return;
case BINOM:
mpz_init (lhs); mpz_init (rhs);
mpz_eval_expr (lhs, e->operands.ops.lhs);
mpz_eval_expr (rhs, e->operands.ops.rhs);
{
unsigned long int k;
if (mpz_cmp_ui (rhs, ~(unsigned long int) 0) > 0)
{
error = "k too large in (n over k) expression";
mpz_clear (lhs); mpz_clear (rhs);
longjmp (errjmpbuf, 1);
}
k = mpz_get_ui (rhs);
mpz_bin_ui (r, lhs, k);
}
mpz_clear (lhs); mpz_clear (rhs);
return;
case TIMING:
{
int t0;
t0 = cputime ();
mpz_eval_expr (r, e->operands.ops.lhs);
printf ("time: %d\n", cputime () - t0);
}
return;
default:
abort ();
}
}
unsigned long tiny_evaluate_candidate(linalg_t * la_inf, QS_t * qs_inf, poly_t * poly_inf,
unsigned long i, unsigned char * sieve)
{
unsigned long bits, exp, extra_bits, modp, prime;
unsigned long num_primes = qs_inf->num_primes;
prime_t * factor_base = qs_inf->factor_base;
unsigned long * soln1 = poly_inf->soln1;
unsigned long * soln2 = poly_inf->soln2;
unsigned long * small = la_inf->small;
fac_t * factor = la_inf->factor;
unsigned long A = poly_inf->A;
unsigned long B = poly_inf->B;
unsigned long num_factors = 0;
unsigned long j;
mpz_t * C = &poly_inf->C;
unsigned long relations = 0;
double pinv;
mpz_t X, Y, res, p;
mpz_init(X);
mpz_init(Y);
mpz_init(res);
mpz_init(p);
#if POLYS
printf("X = %ld\n", i);
printf("%ldX^2+2*%ldX+%ld\n", A, B, C);
#endif
mpz_set_ui(X, i);
mpz_sub_ui(X, X, SIEVE_SIZE/2); //X
mpz_mul_ui(Y, X, A);
if ((long) B < 0)
{
mpz_sub_ui(Y, Y, -B); // Y = AX+B
mpz_sub_ui(res, Y, -B);
}
else
{
mpz_add_ui(Y, Y, B);
mpz_add_ui(res, Y, B);
}
mpz_mul(res, res, X);
mpz_add(res, res, *C); // res = AX^2+2BX+C
bits = mpz_sizeinbase(res, 2);
bits -= 10;
extra_bits = 0;
mpz_set_ui(p, 2); // divide out by powers of 2
exp = mpz_remove(res, res, p);
#if RELATIONS
if (exp) printf("2^%ld ", exp);
#endif
extra_bits += exp;
small[1] = exp;
if (factor_base[0].p != 1) // divide out powers of the multiplier
{
mpz_set_ui(p, factor_base[0].p);
exp = mpz_remove(res, res, p);
if (exp) extra_bits += exp*qs_inf->sizes[0];
small[0] = exp;
#if RELATIONS
if (exp) printf("%ld^%ld ", factor_base[0].p, exp);
#endif
} else small[0] = 0;
for (j = 2; j < SMALL_PRIMES; j++) // pull out small primes
{
prime = factor_base[j].p;
pinv = factor_base[j].pinv;
modp = z_mod_64_precomp(i, prime, pinv);
if ((modp == soln1[j]) || (modp == soln2[j]))
{
mpz_set_ui(p, prime);
exp = mpz_remove(res, res, p);
if (exp) extra_bits += qs_inf->sizes[j];
small[j] = exp;
#if RELATIONS
if (exp) gmp_printf("%Zd^%ld ", p, exp);
#endif
} else small[j] = 0;
}
if (extra_bits + sieve[i] > bits)
{
sieve[i] += extra_bits;
for (j = SMALL_PRIMES; (j < num_primes) && (extra_bits < sieve[i]); j++) // pull out remaining primes
{
prime = factor_base[j].p;
pinv = factor_base[j].pinv;
modp = z_mod_64_precomp(i, prime, pinv);
if (soln2[j] != -1L)
{
if ((modp == soln1[j]) || (modp == soln2[j]))
{
mpz_set_ui(p, prime);
exp = mpz_remove(res, res, p);
#if RELATIONS
if (exp) gmp_printf("%Zd^%ld ", p, exp);
#endif
if (exp)
{
extra_bits += qs_inf->sizes[j];
factor[num_factors].ind = j;
factor[num_factors++].exp = exp;
}
}
} else
{
mpz_set_ui(p, prime);
exp = mpz_remove(res, res, p);
factor[num_factors].ind = j;
factor[num_factors++].exp = exp+1;
#if RELATIONS
if (exp) gmp_printf("%Zd^%ld ", p, exp);
#endif
}
}
if (mpz_cmpabs_ui(res, 1) == 0) // We've found a relation
{
unsigned long * A_ind = poly_inf->A_ind;
unsigned long i;
for (i = 0; i < poly_inf->s; i++) // Commit any outstanding A factors
{
if (A_ind[i] >= j)
{
factor[num_factors].ind = A_ind[i];
factor[num_factors++].exp = 1;
}
}
la_inf->num_factors = num_factors;
relations += tiny_insert_relation(la_inf, poly_inf, Y); // Insert the relation in the matrix
if (la_inf->num_relations >= 2*(qs_inf->num_primes + EXTRA_RELS + 100))
{
printf("Error: too many duplicate relations!\n");
abort();
}
goto cleanup;
}
}
#if RELATIONS
printf("\n");
#endif
cleanup:
mpz_clear(X);
mpz_clear(Y);
mpz_clear(res);
mpz_clear(p);
return relations;
}
int
mpz_perfect_power_p (mpz_srcptr u)
{
unsigned long int prime;
unsigned long int n, n2;
int i;
unsigned long int rem;
mpz_t u2, q;
int exact;
mp_size_t uns;
mp_size_t usize = SIZ (u);
TMP_DECL;
if (mpz_cmpabs_ui (u, 1) <= 0)
return 1; /* -1, 0, and +1 are perfect powers */
n2 = mpz_scan1 (u, 0);
if (n2 == 1)
return 0; /* 2 divides exactly once. */
TMP_MARK;
uns = ABS (usize) - n2 / BITS_PER_MP_LIMB;
MPZ_TMP_INIT (q, uns);
MPZ_TMP_INIT (u2, uns);
mpz_tdiv_q_2exp (u2, u, n2);
mpz_abs (u2, u2);
if (mpz_cmp_ui (u2, 1) == 0)
{
TMP_FREE;
/* factoring completed; consistent power */
return ! (usize < 0 && POW2P(n2));
}
if (isprime (n2))
goto n2prime;
for (i = 1; primes[i] != 0; i++)
{
prime = primes[i];
if (mpz_cmp_ui (u2, prime) < 0)
break;
if (mpz_divisible_ui_p (u2, prime)) /* divisible by this prime? */
{
rem = mpz_tdiv_q_ui (q, u2, prime * prime);
if (rem != 0)
{
TMP_FREE;
return 0; /* prime divides exactly once, reject */
}
mpz_swap (q, u2);
for (n = 2;;)
{
rem = mpz_tdiv_q_ui (q, u2, prime);
if (rem != 0)
break;
mpz_swap (q, u2);
n++;
}
n2 = gcd (n2, n);
if (n2 == 1)
{
TMP_FREE;
return 0; /* we have multiplicity 1 of some factor */
}
if (mpz_cmp_ui (u2, 1) == 0)
{
TMP_FREE;
/* factoring completed; consistent power */
return ! (usize < 0 && POW2P(n2));
}
/* As soon as n2 becomes a prime number, stop factoring.
Either we have u=x^n2 or u is not a perfect power. */
if (isprime (n2))
goto n2prime;
}
}
if (n2 == 0)
{
/* We found no factors above; have to check all values of n. */
unsigned long int nth;
for (nth = usize < 0 ? 3 : 2;; nth++)
{
if (! isprime (nth))
continue;
#if 0
exact = mpz_padic_root (q, u2, nth, PTH);
if (exact)
#endif
exact = mpz_root (q, u2, nth);
if (exact)
{
TMP_FREE;
return 1;
}
if (mpz_cmp_ui (q, SMALLEST_OMITTED_PRIME) < 0)
{
TMP_FREE;
return 0;
}
}
}
else
{
unsigned long int nth;
if (usize < 0 && POW2P(n2))
{
TMP_FREE;
return 0;
}
/* We found some factors above. We just need to consider values of n
that divides n2. */
for (nth = 2; nth <= n2; nth++)
{
if (! isprime (nth))
continue;
if (n2 % nth != 0)
continue;
#if 0
exact = mpz_padic_root (q, u2, nth, PTH);
if (exact)
#endif
exact = mpz_root (q, u2, nth);
if (exact)
{
if (! (usize < 0 && POW2P(nth)))
{
TMP_FREE;
return 1;
}
}
if (mpz_cmp_ui (q, SMALLEST_OMITTED_PRIME) < 0)
{
TMP_FREE;
return 0;
}
}
TMP_FREE;
return 0;
}
n2prime:
if (usize < 0 && POW2P(n2))
{
TMP_FREE;
return 0;
}
exact = mpz_root (NULL, u2, n2);
TMP_FREE;
return exact;
}
int
mpz_probab_prime_p (mpz_srcptr n, int reps)
{
mp_limb_t r;
mpz_t n2;
/* Handle small and negative n. */
if (mpz_cmp_ui (n, 1000000L) <= 0)
{
if (mpz_cmpabs_ui (n, 1000000L) <= 0)
{
int is_prime;
unsigned long n0;
n0 = mpz_get_ui (n);
is_prime = n0 & (n0 > 1) ? isprime (n0) : n0 == 2;
return is_prime ? 2 : 0;
}
/* Negative number. Negate and fall out. */
PTR(n2) = PTR(n);
SIZ(n2) = -SIZ(n);
n = n2;
}
/* If n is now even, it is not a prime. */
if (mpz_even_p (n))
return 0;
#if defined (PP)
/* Check if n has small factors. */
#if defined (PP_INVERTED)
r = MPN_MOD_OR_PREINV_MOD_1 (PTR(n), (mp_size_t) SIZ(n), (mp_limb_t) PP,
(mp_limb_t) PP_INVERTED);
#else
r = mpn_mod_1 (PTR(n), (mp_size_t) SIZ(n), (mp_limb_t) PP);
#endif
if (r % 3 == 0
#if GMP_LIMB_BITS >= 4
|| r % 5 == 0
#endif
#if GMP_LIMB_BITS >= 8
|| r % 7 == 0
#endif
#if GMP_LIMB_BITS >= 16
|| r % 11 == 0 || r % 13 == 0
#endif
#if GMP_LIMB_BITS >= 32
|| r % 17 == 0 || r % 19 == 0 || r % 23 == 0 || r % 29 == 0
#endif
#if GMP_LIMB_BITS >= 64
|| r % 31 == 0 || r % 37 == 0 || r % 41 == 0 || r % 43 == 0
|| r % 47 == 0 || r % 53 == 0
#endif
)
{
return 0;
}
#endif /* PP */
/* Do more dividing. We collect small primes, using umul_ppmm, until we
overflow a single limb. We divide our number by the small primes product,
and look for factors in the remainder. */
{
unsigned long int ln2;
unsigned long int q;
mp_limb_t p1, p0, p;
unsigned int primes[15];
int nprimes;
nprimes = 0;
p = 1;
ln2 = mpz_sizeinbase (n, 2); /* FIXME: tune this limit */
for (q = PP_FIRST_OMITTED; q < ln2; q += 2)
{
if (isprime (q))
{
umul_ppmm (p1, p0, p, q);
if (p1 != 0)
{
r = MPN_MOD_OR_MODEXACT_1_ODD (PTR(n), (mp_size_t) SIZ(n), p);
while (--nprimes >= 0)
if (r % primes[nprimes] == 0)
{
ASSERT_ALWAYS (mpn_mod_1 (PTR(n), (mp_size_t) SIZ(n), (mp_limb_t) primes[nprimes]) == 0);
return 0;
}
p = q;
nprimes = 0;
}
else
{
p = p0;
}
primes[nprimes++] = q;
}
}
}
/* Perform a number of Miller-Rabin tests. */
return mpz_millerrabin (n, reps);
}
int32_t absCompare(const Integer &a, const int32_t b)
{
return mpz_cmpabs_ui( (mpz_srcptr)&(a.gmp_rep), (uint64_t) std::abs(b));
}
