ubuntu-buildroot/output/build/host-gmp-6.2.1/tests/mpz/t-set_d.c

140 lines
3.5 KiB
C

/* Test mpz_set_d and mpz_init_set_d.
Copyright 2000-2003, 2006 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"
void
check_data (void)
{
static const struct {
double d;
mp_size_t want_size;
mp_limb_t want_data[2];
} data[] = {
{ 0.0, 0 },
{ 1.0, 1, { 1 } },
{ -1.0, -1, { 1 } },
{ 123.0, 1, { 123 } },
{ -123.0, -1, { 123 } },
{ 1e-1, 0, { 0 } },
{ -1e-1, 0, { 0 } },
{ 2.328306436538696e-10, 0, { 0 } },
{ -2.328306436538696e-10, 0, { 0 } },
{ 5.421010862427522e-20, 0, { 0 } },
{ -5.421010862427522e-20, 0, { 0 } },
{ 2.938735877055719e-39, 0, { 0 } },
{ -2.938735877055719e-39, 0, { 0 } },
};
mpz_t z;
int i;
for (i = 0; i < numberof (data); i++)
{
mpz_init (z);
mpz_set_d (z, data[i].d);
MPZ_CHECK_FORMAT (z);
if (z->_mp_size != data[i].want_size
|| refmpn_cmp_allowzero (z->_mp_d, data[i].want_data,
ABS (data[i].want_size)) != 0)
{
printf ("mpz_set_d wrong on data[%d]\n", i);
bad:
d_trace (" d ", data[i].d);
printf (" got size %ld\n", (long) z->_mp_size);
printf (" want size %ld\n", (long) data[i].want_size);
mpn_trace (" got z", z->_mp_d, z->_mp_size);
mpn_trace (" want z", data[i].want_data, data[i].want_size);
abort();
}
mpz_clear (z);
mpz_init_set_d (z, data[i].d);
MPZ_CHECK_FORMAT (z);
if (z->_mp_size != data[i].want_size
|| refmpn_cmp_allowzero (z->_mp_d, data[i].want_data,
ABS (data[i].want_size)) != 0)
{
printf ("mpz_init_set_d wrong on data[%d]\n", i);
goto bad;
}
mpz_clear (z);
}
}
/* Try mpz_set_d on values 2^i+1, while such a value fits a double. */
void
check_2n_plus_1 (void)
{
volatile double p, d, diff;
mpz_t want, got;
int i;
mpz_init (want);
mpz_init (got);
p = 1.0;
mpz_set_ui (want, 2L); /* gives 3 on first step */
for (i = 1; i < 500; i++)
{
mpz_mul_2exp (want, want, 1L);
mpz_sub_ui (want, want, 1L); /* want = 2^i+1 */
p *= 2.0; /* p = 2^i */
d = p + 1.0;
diff = d - p;
if (diff != 1.0)
break; /* rounding occurred, stop now */
mpz_set_d (got, d);
MPZ_CHECK_FORMAT (got);
if (mpz_cmp (got, want) != 0)
{
printf ("mpz_set_d wrong on 2^%d+1\n", i);
d_trace (" d ", d);
mpz_trace (" got ", got);
mpz_trace (" want ", want);
abort ();
}
}
mpz_clear (want);
mpz_clear (got);
}
int
main (void)
{
tests_start ();
check_data ();
check_2n_plus_1 ();
tests_end ();
exit (0);
}