xref: /netbsd-src/external/lgpl3/mpfr/dist/src/dump.c (revision ba125506a622fe649968631a56eba5d42ff57863)
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
mpfr_fdump(FILE * stream,mpfr_srcptr x)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
mpfr_dump(mpfr_srcptr x)129 mpfr_dump (mpfr_srcptr x)
130 {
131   mpfr_fdump (stdout, x);
132 }
133