/* Test mpf_get_d and mpf_set_d.

Copyright 1996, 1999-2001, 2009 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.h"

#include "tests.h"

#if defined (__vax) || defined (__vax__)

#define LOW_BOUND 1e-38

#define HIGH_BOUND 8e37

#endif

#if defined (_CRAY) && ! defined (_CRAYIEEE)

/* The range varies mysteriously between Cray version.  On an SV1,

   the range seem to be 1e-600..1e603, but a cfp (non-ieee) T90

   has a much smaller range of 1e-240..1e240.  */

#define LOW_BOUND 1e-240

#define HIGH_BOUND 1e240

#endif

#if ! defined (LOW_BOUND)

#define LOW_BOUND 1e-300

#define HIGH_BOUND 1e300

#endif

void

test_denorms (int prc)

{

#ifdef _GMP_IEEE_FLOATS

  double d1, d2;

  mpf_t f;

  int i;

  mpf_set_default_prec (prc);

  mpf_init (f);

  d1 = 1.9;

  for (i = 0; i < 820; i++)

    {

      mpf_set_d (f, d1);

      d2 = mpf_get_d (f);

      if (d1 != d2)

        abort ();

      d1 *= 0.4;

    }

  mpf_clear (f);

#endif

}

int

main (int argc, char **argv)

{

  double d, e, r;

  mpf_t u, v;

  tests_start ();

  mpf_init (u);

  mpf_init (v);

  mpf_set_d (u, LOW_BOUND);

  for (d = 2.0 * LOW_BOUND; d < HIGH_BOUND; d *= 1.01)

    {

      mpf_set_d (v, d);

      if (mpf_cmp (u, v) >= 0)

	abort ();

      e = mpf_get_d (v);

      r = e/d;

      if (r < 0.99999999999999 || r > 1.00000000000001)

	{

	  fprintf (stderr, "should be one ulp from 1: %.16f\n", r);

	  abort ();

	}

      mpf_set (u, v);

    }

  mpf_clear (u);

  mpf_clear (v);

  test_denorms (10);

  test_denorms (32);

  test_denorms (64);

  test_denorms (100);

  test_denorms (200);

  tests_end ();

  exit (0);

}