src/main.c

   1 /* Top level entry point of Bison.
   2
   3    Copyright (C) 1984, 1986, 1989, 1992, 1995, 2000-2002, 2004-2015,
   4    2018-2022 Free Software Foundation, Inc.
   5
   6    This file is part of Bison, the GNU Compiler Compiler.
   7
   8    This program is free software: you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation, either version 3 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
  20
  21 #include <config.h>
  22 #include "system.h"
  23
  24 #include <bitset.h>
  25 #include <bitset/stats.h>
  26 #include <closeout.h>
  27 #include <configmake.h>
  28 #include <progname.h>
  29 #include <quote.h>
  30 #include <quotearg.h>
  31 #include <relocatable.h> /* relocate2 */
  32 #include <timevar.h>
  33
  34 #include "complain.h"
  35 #include "conflicts.h"
  36 #include "counterexample.h"
  37 #include "derives.h"
  38 #include "files.h"
  39 #include "fixits.h"
  40 #include "getargs.h"
  41 #include "glyphs.h"
  42 #include "gram.h"
  43 #include "ielr.h"
  44 #include "lalr.h"
  45 #include "lr0.h"
  46 #include "muscle-tab.h"
  47 #include "nullable.h"
  48 #include "output.h"
  49 #include "parse-gram.h"
  50 #include "print-graph.h"
  51 #include "print-xml.h"
  52 #include "print.h"
  53 #include "reader.h"
  54 #include "reduce.h"
  55 #include "scan-code.h"
  56 #include "scan-gram.h"
  57 #include "scan-skel.h"
  58 #include "symtab.h"
  59 #include "tables.h"
  60 #include "uniqstr.h"
  61
  62
  63 int
  64 main (int argc, char *argv[])
  65 {
  66   {
  67     char *cp = getenv ("BISON_PROGRAM_NAME");
  68     if (cp)
  69       argv[0] = cp;
  70   }
  71
  72 #define DEPENDS_ON_LIBINTL 1
  73   set_program_name (argv[0]);
  74   setlocale (LC_ALL, "");
  75   {
  76     char *cp = NULL;
  77     char const *localedir = relocate2 (LOCALEDIR, &cp);
  78     bindtextdomain ("bison", localedir);
  79     bindtextdomain ("bison-gnulib", localedir);
  80     bindtextdomain ("bison-runtime", localedir);
  81     free (cp);
  82   }
  83   textdomain ("bison");
  84
  85   {
  86     char const *cp = getenv ("LC_CTYPE");
  87     if (cp && STREQ (cp, "C"))
  88       set_custom_quoting (&quote_quoting_options, "'", "'");
  89     else
  90       set_quoting_style (&quote_quoting_options, locale_quoting_style);
  91   }
  92
  93   atexit (close_stdout);
  94
  95   glyphs_init ();
  96   uniqstrs_new ();
  97   muscle_init ();
  98   complain_init ();
  99   code_scanner_init ();
 100
 101   getargs (argc, argv);
 102
 103   if (trace_flag)
 104     fprintf (stderr, "bison (GNU Bison) %s\n", VERSION);
 105
 106   timevar_enabled = trace_flag & trace_time;
 107   timevar_init ();
 108   timevar_start (tv_total);
 109
 110   if (trace_flag & trace_bitsets)
 111     bitset_stats_enable ();
 112
 113   /* Read the input.  Copy some parts of it to FGUARD, FACTION, FTABLE
 114      and FATTRS.  In file reader.c.  The other parts are recorded in
 115      the grammar; see gram.h.  */
 116
 117   timevar_push (tv_reader);
 118   reader (grammar_file);
 119   timevar_pop (tv_reader);
 120
 121   if (complaint_status == status_complaint)
 122     goto finish;
 123
 124   /* Find useless nonterminals and productions and reduce the grammar. */
 125   timevar_push (tv_reduce);
 126   reduce_grammar ();
 127   timevar_pop (tv_reduce);
 128
 129   /* Record other info about the grammar.  In files derives and
 130      nullable.  */
 131   timevar_push (tv_sets);
 132   derives_compute ();
 133   nullable_compute ();
 134   timevar_pop (tv_sets);
 135
 136   /* Compute LR(0) parser states.  See state.h for more info.  */
 137   timevar_push (tv_lr0);
 138   generate_states ();
 139   timevar_pop (tv_lr0);
 140
 141   /* Add lookahead sets to parser states.  Except when LALR(1) is
 142      requested, split states to eliminate LR(1)-relative
 143      inadequacies.  */
 144   ielr ();
 145
 146   /* Find and record any conflicts: places where one token of
 147      lookahead is not enough to disambiguate the parsing.  In file
 148      conflicts.  Also resolve s/r conflicts based on precedence
 149      declarations.  */
 150   timevar_push (tv_conflicts);
 151   conflicts_solve ();
 152   if (!muscle_percent_define_flag_if ("lr.keep-unreachable-state"))
 153     {
 154       state_number *old_to_new = xnmalloc (nstates, sizeof *old_to_new);
 155       state_number nstates_old = nstates;
 156       state_remove_unreachable_states (old_to_new);
 157       lalr_update_state_numbers (old_to_new, nstates_old);
 158       conflicts_update_state_numbers (old_to_new, nstates_old);
 159       free (old_to_new);
 160     }
 161   if (report_flag & report_cex
 162       || warning_is_enabled (Wcounterexamples))
 163     counterexample_init ();
 164   conflicts_print ();
 165   timevar_pop (tv_conflicts);
 166
 167   /* Compute the parser tables.  */
 168   timevar_push (tv_actions);
 169   tables_generate ();
 170   timevar_pop (tv_actions);
 171
 172   grammar_rules_useless_report (_("rule useless in parser due to conflicts"));
 173
 174   print_precedence_warnings ();
 175
 176   /* Whether to generate output files.  */
 177   bool generate = !(feature_flag & feature_syntax_only);
 178
 179   if (generate)
 180     {
 181       /* Output file names. */
 182       compute_output_file_names ();
 183
 184       /* Output the detailed report on the grammar.  */
 185       if (report_flag)
 186         {
 187           timevar_push (tv_report);
 188           print_results ();
 189           timevar_pop (tv_report);
 190         }
 191
 192       /* Output the graph.  */
 193       if (graph_flag)
 194         {
 195           timevar_push (tv_graph);
 196           print_graph ();
 197           timevar_pop (tv_graph);
 198         }
 199
 200       /* Output xml.  */
 201       if (html_flag || xml_flag)
 202         {
 203           timevar_push (tv_xml);
 204           print_xml ();
 205           timevar_pop (tv_xml);
 206         }
 207
 208       /* Output html.  */
 209       if (html_flag)
 210         {
 211           timevar_push (tv_html);
 212           print_html ();
 213           timevar_pop (tv_html);
 214         }
 215     }
 216
 217   /* Stop if there were errors, to avoid trashing previous output
 218      files.  */
 219   if (complaint_status == status_complaint)
 220     goto finish;
 221
 222   /* Lookahead tokens are no longer needed. */
 223   timevar_push (tv_free);
 224   lalr_free ();
 225   timevar_pop (tv_free);
 226
 227   /* Output the tables and the parser to ftable.  In file output.  */
 228   if (generate)
 229     {
 230       timevar_push (tv_parser);
 231       output ();
 232       timevar_pop (tv_parser);
 233     }
 234
 235  finish:
 236
 237   timevar_push (tv_free);
 238   nullable_free ();
 239   derives_free ();
 240   tables_free ();
 241   states_free ();
 242   reduce_free ();
 243   conflicts_free ();
 244   grammar_free ();
 245   counterexample_free ();
 246   output_file_names_free ();
 247
 248   /* The scanner and parser memory cannot be released right after
 249      parsing, as it contains things such as user actions, prologue,
 250      epilogue etc.  */
 251   gram_scanner_free ();
 252   parser_free ();
 253
 254   muscle_free ();
 255   code_scanner_free ();
 256   skel_scanner_free ();
 257   timevar_pop (tv_free);
 258
 259   if (trace_flag & trace_bitsets)
 260     bitset_stats_dump (stderr);
 261
 262   /* Stop timing and print the times.  */
 263   timevar_stop (tv_total);
 264   timevar_print (stderr);
 265
 266   /* Fix input file now, even if there are errors: that's less
 267      warnings in the following runs.  */
 268   if (!fixits_empty ())
 269     {
 270       if (update_flag)
 271         fixits_run ();
 272       else
 273         complain (NULL, Wother,
 274                   _("fix-its can be applied.  Rerun with option '--update'."));
 275       fixits_free ();
 276     }
 277   uniqstrs_free ();
 278
 279   complain_free ();
 280   quotearg_free ();
 281
 282   return complaint_status ? EXIT_FAILURE : EXIT_SUCCESS;
 283 }