src/main.c

   1 /* Top level entry point of Bison.
   2
   3    Copyright (C) 1984, 1986, 1989, 1992, 1995, 2000-2002, 2004-2012 Free
   4    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 <http://www.gnu.org/licenses/>.  */
  20
  21 #include <config.h>
  22 #include "system.h"
  23
  24 #include <bitset_stats.h>
  25 #include <bitset.h>
  26 #include <configmake.h>
  27 #include <progname.h>
  28 #include <quotearg.h>
  29 #include <timevar.h>
  30
  31 #include "LR0.h"
  32 #include "closeout.h"
  33 #include "complain.h"
  34 #include "conflicts.h"
  35 #include "derives.h"
  36 #include "files.h"
  37 #include "getargs.h"
  38 #include "gram.h"
  39 #include "lalr.h"
  40 #include "ielr.h"
  41 #include "muscle-tab.h"
  42 #include "nullable.h"
  43 #include "output.h"
  44 #include "print.h"
  45 #include "print_graph.h"
  46 #include "print-xml.h"
  47 #include <quote.h>
  48 #include "reader.h"
  49 #include "reduce.h"
  50 #include "scan-code.h"
  51 #include "scan-gram.h"
  52 #include "scan-skel.h"
  53 #include "symtab.h"
  54 #include "tables.h"
  55 #include "uniqstr.h"
  56
  57
  58 int
  59 main (int argc, char *argv[])
  60 {
  61   set_program_name (argv[0]);
  62   setlocale (LC_ALL, "");
  63   (void) bindtextdomain (PACKAGE, LOCALEDIR);
  64   (void) bindtextdomain ("bison-runtime", LOCALEDIR);
  65   (void) textdomain (PACKAGE);
  66
  67   {
  68     char const *cp = getenv ("LC_CTYPE");
  69     if (cp && !strcmp (cp, "C"))
  70       set_custom_quoting (&quote_quoting_options, "'", "'");
  71     else
  72       set_quoting_style (&quote_quoting_options, locale_quoting_style);
  73   }
  74
  75   atexit (close_stdout);
  76
  77   uniqstrs_new ();
  78   muscle_init ();
  79
  80   getargs (argc, argv);
  81
  82   timevar_report = trace_flag & trace_time;
  83   init_timevar ();
  84   timevar_start (TV_TOTAL);
  85
  86   if (trace_flag & trace_bitsets)
  87     bitset_stats_enable ();
  88
  89   /* Read the input.  Copy some parts of it to FGUARD, FACTION, FTABLE
  90      and FATTRS.  In file reader.c.  The other parts are recorded in
  91      the grammar; see gram.h.  */
  92
  93   timevar_push (TV_READER);
  94   reader ();
  95   timevar_pop (TV_READER);
  96
  97   if (complaint_issued)
  98     goto finish;
  99
 100   /* Find useless nonterminals and productions and reduce the grammar. */
 101   timevar_push (TV_REDUCE);
 102   reduce_grammar ();
 103   timevar_pop (TV_REDUCE);
 104
 105   /* Record other info about the grammar.  In files derives and
 106      nullable.  */
 107   timevar_push (TV_SETS);
 108   derives_compute ();
 109   nullable_compute ();
 110   timevar_pop (TV_SETS);
 111
 112   /* Compute LR(0) parser states.  See state.h for more info.  */
 113   timevar_push (TV_LR0);
 114   generate_states ();
 115   timevar_pop (TV_LR0);
 116
 117   /* Add lookahead sets to parser states.  Except when LALR(1) is
 118      requested, split states to eliminate LR(1)-relative
 119      inadequacies.  */
 120   ielr ();
 121
 122   /* Find and record any conflicts: places where one token of
 123      lookahead is not enough to disambiguate the parsing.  In file
 124      conflicts.  Also resolve s/r conflicts based on precedence
 125      declarations.  */
 126   timevar_push (TV_CONFLICTS);
 127   conflicts_solve ();
 128   if (!muscle_percent_define_flag_if ("lr.keep-unreachable-states"))
 129     {
 130       state_number *old_to_new = xnmalloc (nstates, sizeof *old_to_new);
 131       state_number nstates_old = nstates;
 132       state_remove_unreachable_states (old_to_new);
 133       lalr_update_state_numbers (old_to_new, nstates_old);
 134       conflicts_update_state_numbers (old_to_new, nstates_old);
 135       free (old_to_new);
 136     }
 137   conflicts_print ();
 138   timevar_pop (TV_CONFLICTS);
 139
 140   /* Compute the parser tables.  */
 141   timevar_push (TV_ACTIONS);
 142   tables_generate ();
 143   timevar_pop (TV_ACTIONS);
 144
 145   grammar_rules_useless_report
 146     (_("rule useless in parser due to conflicts"));
 147
 148   /* Output file names. */
 149   compute_output_file_names ();
 150
 151   /* Output the detailed report on the grammar.  */
 152   if (report_flag)
 153     {
 154       timevar_push (TV_REPORT);
 155       print_results ();
 156       timevar_pop (TV_REPORT);
 157     }
 158
 159   /* Output the graph.  */
 160   if (graph_flag)
 161     {
 162       timevar_push (TV_GRAPH);
 163       print_graph ();
 164       timevar_pop (TV_GRAPH);
 165     }
 166
 167   /* Output xml.  */
 168   if (xml_flag)
 169     {
 170       timevar_push (TV_XML);
 171       print_xml ();
 172       timevar_pop (TV_XML);
 173     }
 174
 175   /* Stop if there were errors, to avoid trashing previous output
 176      files.  */
 177   if (complaint_issued)
 178     goto finish;
 179
 180   /* Lookahead tokens are no longer needed. */
 181   timevar_push (TV_FREE);
 182   lalr_free ();
 183   timevar_pop (TV_FREE);
 184
 185   /* Output the tables and the parser to ftable.  In file output.  */
 186   timevar_push (TV_PARSER);
 187   output ();
 188   timevar_pop (TV_PARSER);
 189
 190   timevar_push (TV_FREE);
 191   nullable_free ();
 192   derives_free ();
 193   tables_free ();
 194   states_free ();
 195   reduce_free ();
 196   conflicts_free ();
 197   grammar_free ();
 198   output_file_names_free ();
 199
 200   /* The scanner memory cannot be released right after parsing, as it
 201      contains things such as user actions, prologue, epilogue etc.  */
 202   gram_scanner_free ();
 203   muscle_free ();
 204   uniqstrs_free ();
 205   code_scanner_free ();
 206   skel_scanner_free ();
 207   quotearg_free ();
 208   timevar_pop (TV_FREE);
 209
 210   if (trace_flag & trace_bitsets)
 211     bitset_stats_dump (stderr);
 212
 213  finish:
 214
 215   /* Stop timing and print the times.  */
 216   timevar_stop (TV_TOTAL);
 217   timevar_print (stderr);
 218
 219   cleanup_caret ();
 220
 221   return complaint_issued ? EXIT_FAILURE : EXIT_SUCCESS;
 222 }