src/main.c

   1 /* Top level entry point of Bison.
   2
   3    Copyright (C) 1984, 1986, 1989, 1992, 1995, 2000, 2001, 2002, 2004,
   4    2005, 2006, 2007 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 <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 <quotearg.h>
  28 #include <timevar.h>
  29
  30 #include "LR0.h"
  31 #include "complain.h"
  32 #include "conflicts.h"
  33 #include "derives.h"
  34 #include "files.h"
  35 #include "getargs.h"
  36 #include "gram.h"
  37 #include "lalr.h"
  38 #include "muscle_tab.h"
  39 #include "nullable.h"
  40 #include "output.h"
  41 #include "print.h"
  42 #include "print_graph.h"
  43 #include "reader.h"
  44 #include "reduce.h"
  45 #include "scan-code.h"
  46 #include "scan-gram.h"
  47 #include "scan-skel.h"
  48 #include "symtab.h"
  49 #include "tables.h"
  50 #include "uniqstr.h"
  51
  52
  53
  54 int
  55 main (int argc, char *argv[])
  56 {
  57   program_name = argv[0];
  58   setlocale (LC_ALL, "");
  59   (void) bindtextdomain (PACKAGE, LOCALEDIR);
  60   (void) bindtextdomain ("bison-runtime", LOCALEDIR);
  61   (void) textdomain (PACKAGE);
  62
  63   uniqstrs_new ();
  64
  65   getargs (argc, argv);
  66
  67   timevar_report = trace_flag & trace_time;
  68   init_timevar ();
  69   timevar_start (TV_TOTAL);
  70
  71   if (trace_flag & trace_bitsets)
  72     bitset_stats_enable ();
  73
  74   muscle_init ();
  75
  76   /* Read the input.  Copy some parts of it to FGUARD, FACTION, FTABLE
  77      and FATTRS.  In file reader.c.  The other parts are recorded in
  78      the grammar; see gram.h.  */
  79
  80   timevar_push (TV_READER);
  81   reader ();
  82   timevar_pop (TV_READER);
  83
  84   if (complaint_issued)
  85     goto finish;
  86
  87   /* Find useless nonterminals and productions and reduce the grammar. */
  88   timevar_push (TV_REDUCE);
  89   reduce_grammar ();
  90   timevar_pop (TV_REDUCE);
  91
  92   /* Record other info about the grammar.  In files derives and
  93      nullable.  */
  94   timevar_push (TV_SETS);
  95   derives_compute ();
  96   nullable_compute ();
  97   timevar_pop (TV_SETS);
  98
  99   /* Convert to nondeterministic finite state machine.  In file LR0.
 100      See state.h for more info.  */
 101   timevar_push (TV_LR0);
 102   generate_states ();
 103   timevar_pop (TV_LR0);
 104
 105   /* make it deterministic.  In file lalr.  */
 106   timevar_push (TV_LALR);
 107   lalr ();
 108   timevar_pop (TV_LALR);
 109
 110   /* Find and record any conflicts: places where one token of
 111      lookahead is not enough to disambiguate the parsing.  In file
 112      conflicts.  Also resolve s/r conflicts based on precedence
 113      declarations.  */
 114   timevar_push (TV_CONFLICTS);
 115   conflicts_solve ();
 116   {
 117     state_number *old_to_new = xnmalloc (nstates, sizeof *old_to_new);
 118     state_number nstates_old = nstates;
 119     state_remove_unreachable_states (old_to_new);
 120     lalr_update_state_numbers (old_to_new, nstates_old);
 121     conflicts_update_state_numbers (old_to_new, nstates_old);
 122     free (old_to_new);
 123   }
 124   conflicts_print ();
 125   timevar_pop (TV_CONFLICTS);
 126
 127   /* Compute the parser tables.  */
 128   timevar_push (TV_ACTIONS);
 129   tables_generate ();
 130   timevar_pop (TV_ACTIONS);
 131
 132   grammar_rules_never_reduced_report
 133     (_("rule never reduced because of conflicts"));
 134
 135   /* Output file names. */
 136   compute_output_file_names ();
 137
 138   /* Output the detailed report on the grammar.  */
 139   if (report_flag)
 140     {
 141       timevar_push (TV_REPORT);
 142       print_results ();
 143       timevar_pop (TV_REPORT);
 144     }
 145
 146   /* Output the graph.  */
 147   if (graph_flag)
 148     {
 149       timevar_push (TV_GRAPH);
 150       print_graph ();
 151       timevar_pop (TV_GRAPH);
 152     }
 153
 154   /* Stop if there were errors, to avoid trashing previous output
 155      files.  */
 156   if (complaint_issued)
 157     goto finish;
 158
 159   /* Lookahead tokens are no longer needed. */
 160   timevar_push (TV_FREE);
 161   lalr_free ();
 162   timevar_pop (TV_FREE);
 163
 164   /* Output the tables and the parser to ftable.  In file output.  */
 165   timevar_push (TV_PARSER);
 166   output ();
 167   timevar_pop (TV_PARSER);
 168
 169   timevar_push (TV_FREE);
 170   nullable_free ();
 171   derives_free ();
 172   tables_free ();
 173   states_free ();
 174   reduce_free ();
 175   conflicts_free ();
 176   grammar_free ();
 177   output_file_names_free ();
 178
 179   /* The scanner memory cannot be released right after parsing, as it
 180      contains things such as user actions, prologue, epilogue etc.  */
 181   gram_scanner_free ();
 182   muscle_free ();
 183   uniqstrs_free ();
 184   code_scanner_free ();
 185   skel_scanner_free ();
 186   quotearg_free ();
 187   timevar_pop (TV_FREE);
 188
 189   if (trace_flag & trace_bitsets)
 190     bitset_stats_dump (stderr);
 191
 192  finish:
 193
 194   /* Stop timing and print the times.  */
 195   timevar_stop (TV_TOTAL);
 196   timevar_print (stderr);
 197
 198   return complaint_issued ? EXIT_FAILURE : EXIT_SUCCESS;
 199 }