1  /* Test file for mpfr_reldiff.
       2  
       3  Copyright 2000-2023 Free Software Foundation, Inc.
       4  Contributed by the AriC and Caramba projects, INRIA.
       5  
       6  This file is part of the GNU MPFR Library.
       7  
       8  The GNU MPFR Library is free software; you can redistribute it and/or modify
       9  it under the terms of the GNU Lesser General Public License as published by
      10  the Free Software Foundation; either version 3 of the License, or (at your
      11  option) any later version.
      12  
      13  The GNU MPFR Library is distributed in the hope that it will be useful, but
      14  WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
      15  or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
      16  License for more details.
      17  
      18  You should have received a copy of the GNU Lesser General Public License
      19  along with the GNU MPFR Library; see the file COPYING.LESSER.  If not, see
      20  https://www.gnu.org/licenses/ or write to the Free Software Foundation, Inc.,
      21  51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. */
      22  
      23  #include "mpfr-test.h"
      24  
      25  #define SPECIAL_MAX 12
      26  
      27  /* copied from reuse.c */
      28  static void
      29  set_special (mpfr_ptr x, unsigned int select)
      30  {
      31    MPFR_ASSERTN (select < SPECIAL_MAX);
      32    switch (select)
      33      {
      34      case 0:
      35        MPFR_SET_NAN (x);
      36        break;
      37      case 1:
      38        MPFR_SET_INF (x);
      39        MPFR_SET_POS (x);
      40        break;
      41      case 2:
      42        MPFR_SET_INF (x);
      43        MPFR_SET_NEG (x);
      44        break;
      45      case 3:
      46        MPFR_SET_ZERO (x);
      47        MPFR_SET_POS  (x);
      48        break;
      49      case 4:
      50        MPFR_SET_ZERO (x);
      51        MPFR_SET_NEG  (x);
      52        break;
      53      case 5:
      54        mpfr_set_str_binary (x, "1");
      55        break;
      56      case 6:
      57        mpfr_set_str_binary (x, "-1");
      58        break;
      59      case 7:
      60        mpfr_set_str_binary (x, "1e-1");
      61        break;
      62      case 8:
      63        mpfr_set_str_binary (x, "1e+1");
      64        break;
      65      case 9:
      66        mpfr_const_pi (x, MPFR_RNDN);
      67        break;
      68      case 10:
      69        mpfr_const_pi (x, MPFR_RNDN);
      70        MPFR_SET_EXP (x, MPFR_GET_EXP (x)-1);
      71        break;
      72      case 11:
      73        mpfr_urandomb (x, RANDS);
      74        if (RAND_BOOL ())
      75          mpfr_neg (x, x, MPFR_RNDN);
      76        break;
      77      default:
      78        MPFR_ASSERTN (0);
      79      }
      80  }
      81  
      82  int
      83  main (void)
      84  {
      85    mpfr_t a1, a2, b, c;
      86    int pa, pb, pc, i, j, r;
      87    int prec[] = { MPFR_PREC_MIN, 3, 16, 32, 53 };
      88  
      89    tests_start_mpfr ();
      90  
      91    /* Just check that mpfr_reldiff(a,b,c,rnd) computes |b-c|/b using the
      92       precision of a, without any optimization. */
      93  
      94    for (pa = 0; pa < numberof(prec); pa++)
      95      {
      96        mpfr_inits2 (prec[pa], a1, a2, (mpfr_ptr) 0);
      97        for (pb = 0; pb < numberof(prec); pb++)
      98          {
      99            mpfr_init2 (b, prec[pb]);
     100            for (pc = 0; pc < numberof(prec); pc++)
     101              {
     102                mpfr_init2 (c, prec[pc]);
     103                for (i = 0; i < SPECIAL_MAX; i++)
     104                  {
     105                    set_special (b, i);
     106                    for (j = 0; j < SPECIAL_MAX; j++)
     107                      {
     108                        set_special (c, j);
     109                        RND_LOOP (r)
     110                          {
     111                            mpfr_rnd_t rnd = (mpfr_rnd_t) r;
     112  
     113                            mpfr_sub (a1, b, c, rnd);
     114                            mpfr_abs (a1, a1, rnd);
     115                            mpfr_div (a1, a1, b, rnd);
     116                            mpfr_reldiff (a2, b, c, rnd);
     117                            if (! SAME_VAL (a1, a2))
     118                              {
     119                                printf ("Error for pa=%d pb=%d pc=%d "
     120                                        "i=%d j=%d rnd=%s\n", pa, pb, pc,
     121                                        i, j, mpfr_print_rnd_mode (rnd));
     122                                printf ("expected ");
     123                                mpfr_dump (a1);
     124                                printf ("got      ");
     125                                mpfr_dump (a2);
     126                                exit (1);
     127                              }
     128                          }
     129                      }
     130                  }
     131                mpfr_clear (c);
     132              }
     133            mpfr_clear (b);
     134          }
     135        mpfr_clears (a1, a2, (mpfr_ptr) 0);
     136      }
     137  
     138    tests_end_mpfr ();
     139    return 0;
     140  }