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/*
Copyright 2012, 2013, 2018, 2020 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 <limits.h>
#include <math.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <float.h>
#include "testutils.h"
#define GMP_LIMB_BITS (sizeof(mp_limb_t) * CHAR_BIT)
mp_bitcnt_t
mpz_mantissasizeinbits (const mpz_t z)
{
return ! mpz_cmp_ui (z, 0) ? 0 :
mpz_sizeinbase (z, 2) - mpz_scan1 (z, 0);
}
#if defined(DBL_MANT_DIG) && FLT_RADIX == 2
int
mpz_get_d_exact_p (const mpz_t z)
{
return mpz_mantissasizeinbits (z) <= DBL_MANT_DIG;
}
#define HAVE_EXACT_P 1
#endif
#define COUNT 10000
void
test_matissa (void)
{
mpz_t x, y;
int i, c;
mpz_init (x);
mpz_init (y);
mini_urandomb (y, 4);
c = i = mpz_get_ui (y);
do {
double d;
int cmp;
mpz_setbit (x, c);
d = mpz_get_d (x);
mpz_set_d (y, d);
if (mpz_cmp_d (y, d) != 0)
{
fprintf (stderr, "mpz_cmp_d (y, d) failed:\n"
"d = %.20g\n"
"i = %i\n"
"c = %i\n",
d, i, c);
abort ();
}
cmp = mpz_cmp (x, y);
#if defined(HAVE_EXACT_P)
if ((mpz_get_d_exact_p (x) != 0) != (cmp == 0))
{
fprintf (stderr, "Not all bits converted:\n"
"d = %.20g\n"
"i = %i\n"
"c = %i\n",
d, i, c);
abort ();
}
#endif
if (cmp < 0)
{
fprintf (stderr, "mpz_get_d failed:\n"
"d = %.20g\n"
"i = %i\n"
"c = %i\n",
d, i, c);
abort ();
}
else if (cmp > 0)
{
if (mpz_cmp_d (x, d) <= 0)
{
fprintf (stderr, "mpz_cmp_d (x, d) failed:\n"
"d = %.20g\n"
"i = %i\n"
"c = %i\n",
d, i, c);
abort ();
}
break;
}
++c;
} while (1);
mpz_clear (x);
mpz_clear (y);
}
#ifndef M_PI
#define M_PI 3.141592653589793238462643383279502884
#endif
static const struct
{
double d;
const char *s;
} values[] = {
{ 0.0, "0" },
{ 0.3, "0" },
{ -0.3, "0" },
{ M_PI, "3" },
{ M_PI*1e15, "b29430a256d21" },
{ -M_PI*1e15, "-b29430a256d21" },
/* 17 * 2^{200} =
27317946752402834684213355569799764242877450894307478200123392 */
{0.2731794675240283468421335556979976424288e62,
"1100000000000000000000000000000000000000000000000000" },
{ 0.0, NULL }
};
void
testmain (int argc, char **argv)
{
unsigned i;
mpz_t x;
for (i = 0; values[i].s; i++)
{
char *s;
mpz_init_set_d (x, values[i].d);
s = mpz_get_str (NULL, 16, x);
if (strcmp (s, values[i].s) != 0)
{
fprintf (stderr, "mpz_set_d failed:\n"
"d = %.20g\n"
"s = %s\n"
"r = %s\n",
values[i].d, s, values[i].s);
abort ();
}
testfree (s);
mpz_clear (x);
}
mpz_init (x);
for (i = 0; i < COUNT; i++)
{
/* Use volatile, to avoid extended precision in floating point
registers, e.g., on m68k and 80387. */
volatile double d, f;
unsigned long m;
int e;
mini_rrandomb (x, GMP_LIMB_BITS);
m = mpz_get_ui (x);
mini_urandomb (x, 8);
e = mpz_get_ui (x) - 100;
d = ldexp ((double) m, e);
mpz_set_d (x, d);
f = mpz_get_d (x);
if (f != floor (d))
{
fprintf (stderr, "mpz_set_d/mpz_get_d failed:\n");
goto dumperror;
}
if ((f == d) ? (mpz_cmp_d (x, d) != 0) : (mpz_cmp_d (x, d) >= 0))
{
fprintf (stderr, "mpz_cmp_d (x, d) failed:\n");
goto dumperror;
}
f = d + 1.0;
if (f > d && ! (mpz_cmp_d (x, f) < 0))
{
fprintf (stderr, "mpz_cmp_d (x, f) failed:\n");
goto dumperror;
}
d = - d;
mpz_set_d (x, d);
f = mpz_get_d (x);
if (f != ceil (d))
{
fprintf (stderr, "mpz_set_d/mpz_get_d failed:\n");
dumperror:
dump ("x", x);
fprintf (stderr, "m = %lx, e = %i\n", m, e);
fprintf (stderr, "d = %.15g\n", d);
fprintf (stderr, "f = %.15g\n", f);
fprintf (stderr, "f - d = %.5g\n", f - d);
abort ();
}
if ((f == d) ? (mpz_cmp_d (x, d) != 0) : (mpz_cmp_d (x, d) <= 0))
{
fprintf (stderr, "mpz_cmp_d (x, d) failed:\n");
goto dumperror;
}
f = d - 1.0;
if (f < d && ! (mpz_cmp_d (x, f) > 0))
{
fprintf (stderr, "mpz_cmp_d (x, f) failed:\n");
goto dumperror;
}
}
mpz_clear (x);
test_matissa();
}
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