/* Test file for mpfr_get_flt and mpfr_set_flt

Copyright 2009, 2010, 2011, 2012 Free Software Foundation, Inc.
Contributed by the AriC and Caramel projects, INRIA.

This file is part of the GNU MPFR Library.

The GNU MPFR Library is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser 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 MPFR Library 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 Lesser General Public
License for more details.

You should have received a copy of the GNU Lesser General Public License
along with the GNU MPFR Library; see the file COPYING.LESSER.  If not, see
http://www.gnu.org/licenses/ or write to the Free Software Foundation, Inc.,
51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. */

#include <stdlib.h>
#include <float.h>     /* for FLT_MIN */
#include "mpfr-test.h"

int
main (void)
{
  mpfr_t x, y;
  float f, g, infp;
  int i;

  infp = (float) DBL_POS_INF;
  if (infp * 0.5 != infp)
    {
      fprintf (stderr, "Error, FLT_MAX + FLT_MAX does not yield INFP\n");
      fprintf (stderr, "(this is probably a compiler bug, please report)\n");
      exit (1);
    }

  tests_start_mpfr ();

  mpfr_init2 (x, 24);
  mpfr_init2 (y, 24);

#if !defined(MPFR_ERRDIVZERO)
  mpfr_set_nan (x);
  f = mpfr_get_flt (x, MPFR_RNDN);
  if (f == f)
    {
      printf ("Error for mpfr_get_flt(NaN)\n");
      exit (1);
    }
  mpfr_set_flt (x, f, MPFR_RNDN);
  if (mpfr_nan_p (x) == 0)
    {
      printf ("Error for mpfr_set_flt(NaN)\n");
      exit (1);
    }

  mpfr_set_inf (x, 1);
  f = mpfr_get_flt (x, MPFR_RNDN);
  mpfr_set_flt (x, f, MPFR_RNDN);
  if (mpfr_inf_p (x) == 0 || mpfr_sgn (x) < 0)
    {
      printf ("Error for mpfr_set_flt(mpfr_get_flt(+Inf)):\n");
      printf ("f=%f, expected -Inf\n", f);
      printf ("got "); mpfr_dump (x);
      exit (1);
    }

  mpfr_set_inf (x, -1);
  f = mpfr_get_flt (x, MPFR_RNDN);
  mpfr_set_flt (x, f, MPFR_RNDN);
  if (mpfr_inf_p (x) == 0 || mpfr_sgn (x) > 0)
    {
      printf ("Error for mpfr_set_flt(mpfr_get_flt(-Inf)):\n");
      printf ("f=%f, expected -Inf\n", f);
      printf ("got "); mpfr_dump (x);
      exit (1);
    }
#endif

  mpfr_set_ui (x, 0, MPFR_RNDN);
  f = mpfr_get_flt (x, MPFR_RNDN);
  mpfr_set_flt (x, f, MPFR_RNDN);
  if (mpfr_zero_p (x) == 0 || MPFR_SIGN (x) < 0)
    {
      printf ("Error for mpfr_set_flt(mpfr_get_flt(+0))\n");
      exit (1);
    }

  mpfr_set_ui (x, 0, MPFR_RNDN);
  mpfr_neg (x, x, MPFR_RNDN);
  f = mpfr_get_flt (x, MPFR_RNDN);
  mpfr_set_flt (x, f, MPFR_RNDN);
  if (mpfr_zero_p (x) == 0 || MPFR_SIGN (x) > 0)
    {
      printf ("Error for mpfr_set_flt(mpfr_get_flt(-0))\n");
      exit (1);
    }

  mpfr_set_ui (x, 17, MPFR_RNDN);
  f = mpfr_get_flt (x, MPFR_RNDN);
  mpfr_set_flt (x, f, MPFR_RNDN);
  if (mpfr_cmp_ui (x, 17) != 0)
    {
      printf ("Error for mpfr_set_flt(mpfr_get_flt(17))\n");
      printf ("expected 17\n");
      printf ("got      ");
      mpfr_dump (x);
      exit (1);
    }

  mpfr_set_si (x, -42, MPFR_RNDN);
  f = mpfr_get_flt (x, MPFR_RNDN);
  mpfr_set_flt (x, f, MPFR_RNDN);
  if (mpfr_cmp_si (x, -42) != 0)
    {
      printf ("Error for mpfr_set_flt(mpfr_get_flt(-42))\n");
      printf ("expected -42\n");
      printf ("got      ");
      mpfr_dump (x);
      exit (1);
    }

  mpfr_set_si_2exp (x, 1, -126, MPFR_RNDN);
  for (i = -126; i < 128; i++)
    {
      f = mpfr_get_flt (x, MPFR_RNDN);
      mpfr_set_flt (y, f, MPFR_RNDN);
      if (mpfr_cmp (x, y) != 0)
        {
          printf ("Error for mpfr_set_flt(mpfr_get_flt(x))\n");
          printf ("expected "); mpfr_dump (x);
          printf ("got      "); mpfr_dump (y);
          exit (1);
        }
      mpfr_mul_2exp (x, x, 1, MPFR_RNDN);
    }

  mpfr_set_prec (x, 53);
  mpfr_set_si_2exp (x, 1, -126, MPFR_RNDN);
  for (i = -126; i < 128; i++)
    {
      mpfr_nextbelow (x);
      f = mpfr_get_flt (x, MPFR_RNDN);
      mpfr_nextabove (x);
      mpfr_set_flt (y, f, MPFR_RNDN);
      if (mpfr_cmp (x, y) != 0)
        {
          printf ("Error for mpfr_set_flt(mpfr_get_flt(x))\n");
          printf ("expected "); mpfr_dump (x);
          printf ("got      "); mpfr_dump (y);
          exit (1);
        }
      mpfr_mul_2exp (x, x, 1, MPFR_RNDN);
    }

  mpfr_set_prec (x, 53);
  mpfr_set_si_2exp (x, 1, -126, MPFR_RNDN);
  for (i = -126; i < 128; i++)
    {
      mpfr_nextabove (x);
      f = mpfr_get_flt (x, MPFR_RNDN);
      mpfr_nextbelow (x);
      mpfr_set_flt (y, f, MPFR_RNDN);
      if (mpfr_cmp (x, y) != 0)
        {
          printf ("Error for mpfr_set_flt(mpfr_get_flt(x))\n");
          printf ("expected "); mpfr_dump (x);
          printf ("got      "); mpfr_dump (y);
          exit (1);
        }
      mpfr_mul_2exp (x, x, 1, MPFR_RNDN);
    }

  mpfr_set_si_2exp (x, 1, -150, MPFR_RNDN);
  g = 0.0;
  f = mpfr_get_flt (x, MPFR_RNDN);
  if (f != g)
    {
      printf ("Error for mpfr_get_flt(2^(-150),RNDN)\n");
      printf ("expected %.8e, got %.8e\n", g, f);
      exit (1);
    }
  f = mpfr_get_flt (x, MPFR_RNDZ);
  if (f != g)
    {
      printf ("Error for mpfr_get_flt(2^(-150),RNDZ)\n");
      printf ("expected %.8e, got %.8e\n", g, f);
      exit (1);
    }
  f = mpfr_get_flt (x, MPFR_RNDD);
  if (f != g)
    {
      printf ("Error for mpfr_get_flt(2^(-150),RNDD)\n");
      printf ("expected %.8e, got %.8e\n", g, f);
      exit (1);
    }
  g = FLT_MIN * FLT_EPSILON;
  f = mpfr_get_flt (x, MPFR_RNDU);
  if (f != g)
    {
      printf ("Error for mpfr_get_flt(2^(-150),RNDU)\n");
      printf ("expected %.8e, got %.8e\n", g, f);
      exit (1);
    }
  f = mpfr_get_flt (x, MPFR_RNDA);
  if (f != g)
    {
      printf ("Error for mpfr_get_flt(2^(-150),RNDA)\n");
      printf ("expected %.8e, got %.8e\n", g, f);
      exit (1);
    }

  mpfr_set_si_2exp (x, 1, -151, MPFR_RNDN);
  g = 0.0;
  f = mpfr_get_flt (x, MPFR_RNDN);
  if (f != g)
    {
      printf ("Error for mpfr_get_flt(2^(-151),RNDN)\n");
      printf ("expected %.8e, got %.8e\n", g, f);
      exit (1);
    }
  f = mpfr_get_flt (x, MPFR_RNDZ);
  if (f != g)
    {
      printf ("Error for mpfr_get_flt(2^(-151),RNDZ)\n");
      printf ("expected %.8e, got %.8e\n", g, f);
      exit (1);
    }
  f = mpfr_get_flt (x, MPFR_RNDD);
  if (f != g)
    {
      printf ("Error for mpfr_get_flt(2^(-151),RNDD)\n");
      printf ("expected %.8e, got %.8e\n", g, f);
      exit (1);
    }
  g = FLT_MIN * FLT_EPSILON;
  f = mpfr_get_flt (x, MPFR_RNDU);
  if (f != g)
    {
      printf ("Error for mpfr_get_flt(2^(-151),RNDU)\n");
      printf ("expected %.8e, got %.8e\n", g, f);
      exit (1);
    }
  f = mpfr_get_flt (x, MPFR_RNDA);
  if (f != g)
    {
      printf ("Error for mpfr_get_flt(2^(-151),RNDA)\n");
      printf ("expected %.8e, got %.8e\n", g, f);
      exit (1);
    }

  mpfr_set_si_2exp (x, 1, -149, MPFR_RNDN);
  g = FLT_MIN * FLT_EPSILON;
  f = mpfr_get_flt (x, MPFR_RNDN);
  if (f != g)
    {
      printf ("Error for mpfr_get_flt(2^(-149),RNDN)\n");
      printf ("expected %.8e, got %.8e\n", g, f);
      exit (1);
    }
  f = mpfr_get_flt (x, MPFR_RNDZ);
  if (f != g)
    {
      printf ("Error for mpfr_get_flt(2^(-149),RNDZ)\n");
      printf ("expected %.8e, got %.8e\n", g, f);
      exit (1);
    }
  f = mpfr_get_flt (x, MPFR_RNDD);
  if (f != g)
    {
      printf ("Error for mpfr_get_flt(2^(-149),RNDD)\n");
      printf ("expected %.8e, got %.8e\n", g, f);
      exit (1);
    }
  f = mpfr_get_flt (x, MPFR_RNDU);
  if (f != g)
    {
      printf ("Error for mpfr_get_flt(2^(-149),RNDU)\n");
      printf ("expected %.8e, got %.8e\n", g, f);
      exit (1);
    }
  f = mpfr_get_flt (x, MPFR_RNDA);
  if (f != g)
    {
      printf ("Error for mpfr_get_flt(2^(-149),RNDA)\n");
      printf ("expected %.8e, got %.8e\n", g, f);
      exit (1);
    }

  mpfr_set_si_2exp (x, 1, 128, MPFR_RNDN);
  g = FLT_MAX;
  f = mpfr_get_flt (x, MPFR_RNDZ);
  if (f != g)
    {
      printf ("Error for mpfr_get_flt(2^128,RNDZ)\n");
      printf ("expected %.8e, got %.8e\n", g, f);
      exit (1);
    }
  f = mpfr_get_flt (x, MPFR_RNDD);
  if (f != g)
    {
      printf ("Error for mpfr_get_flt(2^128,RNDD)\n");
      printf ("expected %.8e, got %.8e\n", g, f);
      exit (1);
    }
#if !defined(MPFR_ERRDIVZERO)
  f = mpfr_get_flt (x, MPFR_RNDN); /* 2^128 rounds to itself with extended
                                      exponent range, we should get +Inf */
  g = infp;
  if (f != g)
    {
      printf ("Error for mpfr_get_flt(2^128,RNDN)\n");
      printf ("expected %.8e, got %.8e\n", g, f);
      exit (1);
    }
  f = mpfr_get_flt (x, MPFR_RNDU);
  if (f != g)
    {
      printf ("Error for mpfr_get_flt(2^128,RNDU)\n");
      printf ("expected %.8e, got %.8e\n", g, f);
      exit (1);
    }
  f = mpfr_get_flt (x, MPFR_RNDA);
  if (f != g)
    {
      printf ("Error for mpfr_get_flt(2^128,RNDA)\n");
      printf ("expected %.8e, got %.8e\n", g, f);
      exit (1);
    }
#endif

  /* corner case: take x with 25 bits just below 2^128 */
  mpfr_set_prec (x, 25);
  mpfr_set_si_2exp (x, 1, 128, MPFR_RNDN);
  mpfr_nextbelow (x);
  g = FLT_MAX;
  f = mpfr_get_flt (x, MPFR_RNDZ);
  if (f != g)
    {
      printf ("Error for mpfr_get_flt(2^128*(1-2^(-25)),RNDZ)\n");
      printf ("expected %.8e, got %.8e\n", g, f);
      exit (1);
    }
  f = mpfr_get_flt (x, MPFR_RNDD);
  if (f != g)
    {
      printf ("Error for mpfr_get_flt(2^128*(1-2^(-25)),RNDD)\n");
      printf ("expected %.8e, got %.8e\n", g, f);
      exit (1);
    }
  f = mpfr_get_flt (x, MPFR_RNDN); /* first round to 2^128 (even rule),
                                      thus we should get +Inf */
  g = infp;
  if (f != g)
    {
      printf ("Error for mpfr_get_flt(2^128*(1-2^(-25)),RNDN)\n");
      printf ("expected %.8e, got %.8e\n", g, f);
      exit (1);
    }
  f = mpfr_get_flt (x, MPFR_RNDU);
  if (f != g)
    {
      printf ("Error for mpfr_get_flt(2^128*(1-2^(-25)),RNDU)\n");
      printf ("expected %.8e, got %.8e\n", g, f);
      exit (1);
    }
  f = mpfr_get_flt (x, MPFR_RNDA);
  if (f != g)
    {
      printf ("Error for mpfr_get_flt(2^128*(1-2^(-25)),RNDA)\n");
      printf ("expected %.8e, got %.8e\n", g, f);
      exit (1);
    }

  mpfr_clear (x);
  mpfr_clear (y);

  tests_end_mpfr ();
  return 0;
}
