/* Test mpz_cmp_d and mpz_cmpabs_d.
Copyright 2001-2003, 2005, 2013 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 <math.h>
#include "testutils.h"
/* FIXME: Not sure if the tests here are exhaustive. Ought to try to get
each possible exit from mpz_cmp_d (and mpz_cmpabs_d) exercised. */
#define SGN(n) ((n) > 0 ? 1 : (n) < 0 ? -1 : 0)
void
check_one (const char *name, mpz_srcptr x, double y, int cmp, int cmpabs)
{
int got;
got = mpz_cmp_d (x, y);
if (SGN(got) != cmp)
{
unsigned i;
printf ("mpz_cmp_d wrong (from %s)\n", name);
printf (" got %d\n", got);
printf (" want %d\n", cmp);
fail:
printf (" x=");
mpz_out_str (stdout, 10, x);
printf ("\n y %g\n", y);
printf (" x=0x");
mpz_out_str (stdout, -16, x);
printf ("\n y %g\n", y);
printf (" y");
for (i = 0; i < sizeof(y); i++)
printf (" %02X", (unsigned) ((unsigned char *) &y)[i]);
printf ("\n");
abort ();
}
got = mpz_cmpabs_d (x, y);
if (SGN(got) != cmpabs)
{
printf ("mpz_cmpabs_d wrong\n");
printf (" got %d\n", got);
printf (" want %d\n", cmpabs);
goto fail;
}
}
void
check_data (void)
{
static const struct {
const char *x;
double y;
int cmp, cmpabs;
} data[] = {
{ "0", 0.0, 0, 0 },
{ "1", 0.0, 1, 1 },
{ "-1", 0.0, -1, 1 },
{ "1", 0.5, 1, 1 },
{ "-1", -0.5, -1, 1 },
{ "0", 1.0, -1, -1 },
{ "0", -1.0, 1, -1 },
{ "0x1000000000000000000000000000000000000000000000000", 1.0, 1, 1 },
{ "-0x1000000000000000000000000000000000000000000000000", 1.0, -1, 1 },
{ "0", 1e100, -1, -1 },
{ "0", -1e100, 1, -1 },
{ "2", 1.5, 1, 1 },
{ "2", -1.5, 1, 1 },
{ "-2", 1.5, -1, 1 },
{ "-2", -1.5, -1, 1 },
};
mpz_t x;
unsigned i;
mpz_init (x);
for (i = 0; i < numberof (data); i++)
{
mpz_set_str_or_abort (x, data[i].x, 0);
check_one ("check_data", x, data[i].y, data[i].cmp, data[i].cmpabs);
}
mpz_clear (x);
}
/* Equality of integers with up to 53 bits */
void
check_onebits (void)
{
mpz_t x, x2;
double y;
int i;
mpz_init_set_ui (x, 0L);
mpz_init (x2);
for (i = 0; i < 512; i++)
{
mpz_mul_2exp (x, x, 1);
mpz_add_ui (x, x, 1L);
y = mpz_get_d (x);
mpz_set_d (x2, y);
/* stop if any truncation is occurring */
if (mpz_cmp (x, x2) != 0)
break;
check_one ("check_onebits", x, y, 0, 0);
check_one ("check_onebits", x, -y, 1, 0);
mpz_neg (x, x);
check_one ("check_onebits", x, y, -1, 0);
check_one ("check_onebits", x, -y, 0, 0);
mpz_neg (x, x);
}
mpz_clear (x);
mpz_clear (x2);
}
/* With the mpz differing by 1, in a limb position possibly below the double */
void
check_low_z_one (void)
{
mpz_t x;
double y;
unsigned long i;
mpz_init (x);
/* FIXME: It'd be better to base this on the float format. */
#if defined (__vax) || defined (__vax__)
#define LIM 127 /* vax fp numbers have limited range */
#else
#define LIM 512
#endif
for (i = 1; i < LIM; i++)
{
mpz_set_ui (x, 1L);
mpz_mul_2exp (x, x, i);
y = mpz_get_d (x);
check_one ("check_low_z_one", x, y, 0, 0);
check_one ("check_low_z_one", x, -y, 1, 0);
mpz_neg (x, x);
check_one ("check_low_z_one", x, y, -1, 0);
check_one ("check_low_z_one", x, -y, 0, 0);
mpz_neg (x, x);
mpz_sub_ui (x, x, 1);
check_one ("check_low_z_one", x, y, -1, -1);
check_one ("check_low_z_one", x, -y, 1, -1);
mpz_neg (x, x);
check_one ("check_low_z_one", x, y, -1, -1);
check_one ("check_low_z_one", x, -y, 1, -1);
mpz_neg (x, x);
mpz_add_ui (x, x, 2);
check_one ("check_low_z_one", x, y, 1, 1);
check_one ("check_low_z_one", x, -y, 1, 1);
mpz_neg (x, x);
check_one ("check_low_z_one", x, y, -1, 1);
check_one ("check_low_z_one", x, -y, -1, 1);
mpz_neg (x, x);
}
mpz_clear (x);
}
/* Comparing 1 and 1+2^-n. "y" is volatile to make gcc store and fetch it,
which forces it to a 64-bit double, whereas on x86 it would otherwise
remain on the float stack as an 80-bit long double. */
void
check_one_2exp (void)
{
double e;
mpz_t x;
volatile double y;
int i;
mpz_init (x);
e = 1.0;
for (i = 0; i < 128; i++)
{
e /= 2.0;
y = 1.0 + e;
if (y == 1.0)
break;
mpz_set_ui (x, 1L);
check_one ("check_one_2exp", x, y, -1, -1);
check_one ("check_one_2exp", x, -y, 1, -1);
mpz_set_si (x, -1L);
check_one ("check_one_2exp", x, y, -1, -1);
check_one ("check_one_2exp", x, -y, 1, -1);
}
mpz_clear (x);
}
void
check_infinity (void)
{
mpz_t x;
double y = HUGE_VAL;
if (y != 2*y)
return;
mpz_init (x);
/* 0 cmp inf */
mpz_set_ui (x, 0L);
check_one ("check_infinity", x, y, -1, -1);
check_one ("check_infinity", x, -y, 1, -1);
/* 123 cmp inf */
mpz_set_ui (x, 123L);
check_one ("check_infinity", x, y, -1, -1);
check_one ("check_infinity", x, -y, 1, -1);
/* -123 cmp inf */
mpz_set_si (x, -123L);
check_one ("check_infinity", x, y, -1, -1);
check_one ("check_infinity", x, -y, 1, -1);
/* 2^5000 cmp inf */
mpz_set_ui (x, 1L);
mpz_mul_2exp (x, x, 5000L);
check_one ("check_infinity", x, y, -1, -1);
check_one ("check_infinity", x, -y, 1, -1);
/* -2^5000 cmp inf */
mpz_neg (x, x);
check_one ("check_infinity", x, y, -1, -1);
check_one ("check_infinity", x, -y, 1, -1);
mpz_clear (x);
}
void
testmain (int argc, char *argv[])
{
check_data ();
check_onebits ();
check_low_z_one ();
check_one_2exp ();
check_infinity ();
}