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/* Test mpz_[cft]div_[qr]_2exp.
Copyright 2001 Free Software Foundation, Inc.
This file is part of the GNU MP Library test suite.
The GNU MP Library test suite is free software; you can redistribute it
and/or modify it under the terms of the GNU General Public License as
published by the Free Software Foundation; either version 3 of the License,
or (at your option) any later version.
The GNU MP Library test suite is distributed in the hope that it will be
useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
Public License for more details.
You should have received a copy of the GNU General Public License along with
the GNU MP Library test suite. If not, see https://www.gnu.org/licenses/. */
#include <stdio.h>
#include <stdlib.h>
#include "gmp-impl.h"
#include "tests.h"
/* If the remainder is in the correct range and q*d+r is correct, then q
must have rounded correctly. */
void
check_one (mpz_srcptr a, unsigned long d)
{
mpz_t q, r, p, d2exp;
int inplace;
mpz_init (d2exp);
mpz_init (q);
mpz_init (r);
mpz_init (p);
mpz_set_ui (d2exp, 1L);
mpz_mul_2exp (d2exp, d2exp, d);
#define INPLACE(fun,dst,src,d) \
if (inplace) \
{ \
mpz_set (dst, src); \
fun (dst, dst, d); \
} \
else \
fun (dst, src, d);
for (inplace = 0; inplace <= 1; inplace++)
{
INPLACE (mpz_fdiv_q_2exp, q, a, d);
INPLACE (mpz_fdiv_r_2exp, r, a, d);
mpz_mul_2exp (p, q, d);
mpz_add (p, p, r);
if (mpz_sgn (r) < 0 || mpz_cmp (r, d2exp) >= 0)
{
printf ("mpz_fdiv_r_2exp result out of range\n");
goto error;
}
if (mpz_cmp (p, a) != 0)
{
printf ("mpz_fdiv_[qr]_2exp doesn't multiply back\n");
goto error;
}
INPLACE (mpz_cdiv_q_2exp, q, a, d);
INPLACE (mpz_cdiv_r_2exp, r, a, d);
mpz_mul_2exp (p, q, d);
mpz_add (p, p, r);
if (mpz_sgn (r) > 0 || mpz_cmpabs (r, d2exp) >= 0)
{
printf ("mpz_cdiv_r_2exp result out of range\n");
goto error;
}
if (mpz_cmp (p, a) != 0)
{
printf ("mpz_cdiv_[qr]_2exp doesn't multiply back\n");
goto error;
}
INPLACE (mpz_tdiv_q_2exp, q, a, d);
INPLACE (mpz_tdiv_r_2exp, r, a, d);
mpz_mul_2exp (p, q, d);
mpz_add (p, p, r);
if (mpz_sgn (r) != 0 && mpz_sgn (r) != mpz_sgn (a))
{
printf ("mpz_tdiv_r_2exp result wrong sign\n");
goto error;
}
if (mpz_cmpabs (r, d2exp) >= 0)
{
printf ("mpz_tdiv_r_2exp result out of range\n");
goto error;
}
if (mpz_cmp (p, a) != 0)
{
printf ("mpz_tdiv_[qr]_2exp doesn't multiply back\n");
goto error;
}
}
mpz_clear (d2exp);
mpz_clear (q);
mpz_clear (r);
mpz_clear (p);
return;
error:
mpz_trace ("a", a);
printf ("d=%lu\n", d);
mpz_trace ("q", q);
mpz_trace ("r", r);
mpz_trace ("p", p);
mp_trace_base = -16;
mpz_trace ("a", a);
printf ("d=0x%lX\n", d);
mpz_trace ("q", q);
mpz_trace ("r", r);
mpz_trace ("p", p);
abort ();
}
void
check_all (mpz_ptr a, unsigned long d)
{
check_one (a, d);
mpz_neg (a, a);
check_one (a, d);
}
void
check_various (void)
{
static const unsigned long table[] = {
0, 1, 2, 3, 4, 5,
GMP_NUMB_BITS-1, GMP_NUMB_BITS, GMP_NUMB_BITS+1,
2*GMP_NUMB_BITS-1, 2*GMP_NUMB_BITS, 2*GMP_NUMB_BITS+1,
3*GMP_NUMB_BITS-1, 3*GMP_NUMB_BITS, 3*GMP_NUMB_BITS+1,
4*GMP_NUMB_BITS-1, 4*GMP_NUMB_BITS, 4*GMP_NUMB_BITS+1
};
int i, j;
unsigned long n, d;
mpz_t a;
mpz_init (a);
/* a==0, and various d */
mpz_set_ui (a, 0L);
for (i = 0; i < numberof (table); i++)
check_one (a, table[i]);
/* a==2^n, and various d */
for (i = 0; i < numberof (table); i++)
{
n = table[i];
mpz_set_ui (a, 1L);
mpz_mul_2exp (a, a, n);
for (j = 0; j < numberof (table); j++)
{
d = table[j];
check_all (a, d);
}
}
mpz_clear (a);
}
void
check_random (int argc, char *argv[])
{
gmp_randstate_ptr rands = RANDS;
int reps = 100;
mpz_t a;
unsigned long d;
int i;
if (argc == 2)
reps = atoi (argv[1]);
mpz_init (a);
for (i = 0; i < reps; i++)
{
/* exponentially within 2 to 257 bits */
mpz_erandomb (a, rands, urandom () % 8 + 2);
d = urandom () % 256;
check_all (a, d);
}
mpz_clear (a);
}
int
main (int argc, char *argv[])
{
tests_start ();
check_various ();
check_random (argc, argv);
tests_end ();
exit (0);
}
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