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      1 /* mpfr_dump, mpfr_fdump -- dump a float (for the tests and debugging purpose)
      2 
      3 Copyright 1999-2023 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-impl.h"
     24 
     25 /* mpfr_dump is mainly for debugging purpose. It outputs a MPFR number
     26  * in some unspecified format, then a newline character. This function
     27  * is part of the API, but the output format may change without breaking
     28  * the ABI.
     29  *
     30  * Since this is for debugging, it can detect invalid data (or UBF), and
     31  * in such a case, it outputs information between exclamation marks:
     32  *   - 'N': the number is not normalized (MSB = 0);
     33  *   - 'T': there are non-zero trailing bits (output in square brackets);
     34  *   - 'U': this is an UBF number (internal use only);
     35  *   - '<': the exponent is < the current emin;
     36  *   - '>': the exponent is > the current emax.
     37  *
     38  * The format may depend on MPFR_* environment variables. For instance,
     39  * in the future, some environment variables could specify prefix and
     40  * suffix strings to colorize parts of the output that correspond to
     41  * invalid data.
     42  */
     43 
     44 void
     45 mpfr_fdump (FILE *stream, mpfr_srcptr x)
     46 {
     47   if (MPFR_IS_NEG (x))
     48     fprintf (stream, "-");
     49 
     50   if (MPFR_IS_NAN (x))
     51     fprintf (stream, "@NaN@");
     52   else if (MPFR_IS_INF (x))
     53     fprintf (stream, "@Inf@");
     54   else if (MPFR_IS_ZERO (x))
     55     fprintf (stream, "0");
     56   else
     57     {
     58       mp_limb_t *mx;
     59       mpfr_prec_t px;
     60       mp_size_t n;
     61       char invalid[4];
     62       int first = 1, i = 0;
     63 
     64       mx = MPFR_MANT (x);
     65       px = MPFR_PREC (x);
     66 
     67       fprintf (stream, "0.");
     68       for (n = (px - 1) / GMP_NUMB_BITS; n >= 0; n--)
     69         {
     70           mp_limb_t wd, t;
     71 
     72           wd = mx[n];
     73           if (first)
     74             {
     75               if (! MPFR_LIMB_MSB (wd))
     76                 invalid[i++] = 'N';
     77               first = 0;
     78             }
     79           for (t = MPFR_LIMB_HIGHBIT; t != 0; t >>= 1)
     80             {
     81               putc ((wd & t) == 0 ? '0' : '1', stream);
     82               if (--px == 0)
     83                 {
     84                   MPFR_ASSERTD (n == 0);
     85                   if (t != 0 && (wd & (t - 1)) != 0)
     86                     {
     87                       putc ('[', stream);
     88                       invalid[i++] = 'T';
     89                     }
     90                   else
     91                     break; /* the trailing bits (all 0's) are not output */
     92                 }
     93             }
     94         }
     95       if (px < 0)  /* there are non-zero trailing bits */
     96         putc (']', stream);
     97 
     98       if (MPFR_IS_UBF (x))
     99         {
    100 #ifndef MPFR_USE_MINI_GMP
    101           gmp_fprintf (stream, "E%Zd", MPFR_ZEXP (x));
    102 #else /* mini-gmp has no gmp_fprintf */
    103           fprintf (stream, "E");
    104           mpz_out_str (stream, 10, MPFR_ZEXP (x));
    105 #endif
    106           invalid[i++] = 'U';
    107         }
    108       else
    109         {
    110           mpfr_exp_t e = MPFR_EXP (x);
    111 
    112           fprintf (stream, "E%" MPFR_EXP_FSPEC "d", (mpfr_eexp_t) e);
    113           if (e < __gmpfr_emin)
    114             invalid[i++] = '<';
    115           else if (e > __gmpfr_emax)
    116             invalid[i++] = '>';
    117         }
    118 
    119       if (i != 0)
    120         {
    121           invalid[i] = '\0';
    122           fprintf (stream, "!!!%s!!!", invalid);
    123         }
    124     }
    125   putc ('\n', stream);
    126 }
    127 
    128 void
    129 mpfr_dump (mpfr_srcptr x)
    130 {
    131   mpfr_fdump (stdout, x);
    132 }
    133