stdlib/gen-tst-strtod-round.c

   1 /* Generate table of tests in tst-strtod-round.c from
   2    tst-strtod-round-data.
   3    Copyright (C) 2012 Free Software Foundation, Inc.
   4    This file is part of the GNU C Library.
   5
   6    The GNU C Library is free software; you can redistribute it and/or
   7    modify it under the terms of the GNU Lesser General Public
   8    License as published by the Free Software Foundation; either
   9    version 2.1 of the License, or (at your option) any later version.
  10
  11    The GNU C Library is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14    Lesser General Public License for more details.
  15
  16    You should have received a copy of the GNU Lesser General Public
  17    License along with the GNU C Library; if not, see
  18    <http://www.gnu.org/licenses/>.  */
  19
  20 #define _GNU_SOURCE
  21 #include <assert.h>
  22 #include <stdbool.h>
  23 #include <stdio.h>
  24 #include <stdlib.h>
  25 #include <mpfr.h>
  26
  27 /* Work around incorrect ternary value from mpfr_strtofr
  28    <https://sympa.inria.fr/sympa/arc/mpfr/2012-08/msg00005.html>.  */
  29 #define WORKAROUND
  30
  31 static int
  32 string_to_fp (mpfr_t f, const char *s, mpfr_rnd_t rnd)
  33 {
  34 #ifdef WORKAROUND
  35   mpfr_t f2;
  36   mpfr_init2 (f2, 100000);
  37   int r0 = mpfr_strtofr (f2, s, NULL, 0, rnd);
  38   int r = mpfr_set (f, f2, rnd);
  39   mpfr_subnormalize (f, r, rnd);
  40   mpfr_clear (f2);
  41   return r0 | r;
  42 #else
  43   int r = mpfr_strtofr (f, s, NULL, 0, rnd);
  44   mpfr_subnormalize (f, r, rnd);
  45   return r;
  46 #endif
  47 }
  48
  49 static void
  50 print_fp (mpfr_t f, const char *suffix, const char *suffix2)
  51 {
  52   if (mpfr_inf_p (f))
  53     mpfr_printf ("\t%sINFINITY%s", mpfr_signbit (f) ? "-" : "", suffix2);
  54   else
  55     mpfr_printf ("\t%Ra%s%s", f, suffix, suffix2);
  56 }
  57
  58 static void
  59 round_str (const char *s, const char *suffix,
  60            int prec, int emin, int emax, bool need_exact)
  61 {
  62   mpfr_t f;
  63   mpfr_set_default_prec (prec);
  64   mpfr_set_emin (emin);
  65   mpfr_set_emax (emax);
  66   mpfr_init (f);
  67   int r = string_to_fp (f, s, MPFR_RNDD);
  68   if (need_exact)
  69     {
  70       assert (prec == 106 && emin == -1073 && emax == 1024);
  71       /* The maximum value in IBM long double has discontiguous
  72          mantissa bits.  */
  73       mpfr_t max_value;
  74       mpfr_init2 (max_value, 107);
  75       mpfr_set_str (max_value, "0x1.fffffffffffff7ffffffffffffcp+1023", 0,
  76                     MPFR_RNDN);
  77       if (mpfr_cmpabs (f, max_value) > 0)
  78         r = 1;
  79       mpfr_printf ("\t%s,\n", r ? "false" : "true");
  80       mpfr_clear (max_value);
  81     }
  82   print_fp (f, suffix, ",\n");
  83   string_to_fp (f, s, MPFR_RNDN);
  84   print_fp (f, suffix, ",\n");
  85   string_to_fp (f, s, MPFR_RNDZ);
  86   print_fp (f, suffix, ",\n");
  87   string_to_fp (f, s, MPFR_RNDU);
  88   print_fp (f, suffix, "");
  89   mpfr_clear (f);
  90 }
  91
  92 static void
  93 round_for_all (const char *s)
  94 {
  95   static const struct fmt {
  96     const char *suffix;
  97     int prec;
  98     int emin;
  99     int emax;
 100     bool need_exact;
 101   } formats[7] = {
 102     { "f", 24, -148, 128, false },
 103     { "", 53, -1073, 1024, false },
 104     { "L", 53, -1073, 1024, false },
 105     /* This is the Intel extended float format.  */
 106     { "L", 64, -16444, 16384, false },
 107     /* This is the Motorola extended float format.  */
 108     { "L", 64, -16445, 16384, false },
 109     { "L", 106, -1073, 1024, true },
 110     { "L", 113, -16493, 16384, false },
 111   };
 112   mpfr_printf ("  TEST (\"");
 113   const char *p;
 114   for (p = s; *p; p++)
 115     {
 116       putchar (*p);
 117       if ((p - s) % 60 == 59 && p[1])
 118         mpfr_printf ("\"\n\t\"");
 119     }
 120   mpfr_printf ("\",\n");
 121   int i;
 122   for (i = 0; i < 7; i++)
 123     {
 124       round_str (s, formats[i].suffix, formats[i].prec,
 125                  formats[i].emin, formats[i].emax, formats[i].need_exact);
 126       if (i < 6)
 127         mpfr_printf (",\n");
 128     }
 129   mpfr_printf ("),\n");
 130 }
 131
 132 int
 133 main (void)
 134 {
 135   char *p = NULL;
 136   size_t len;
 137   ssize_t nbytes;
 138   while ((nbytes = getline (&p, &len, stdin)) != -1)
 139     {
 140       if (p[nbytes - 1] == '\n')
 141         p[nbytes - 1] = 0;
 142       round_for_all (p);
 143       free (p);
 144       p = NULL;
 145     }
 146   return 0;
 147 }