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 "reader.h"
  48 #include "reduce.h"
  49 #include "scan-code.h"
  50 #include "scan-gram.h"
  51 #include "scan-skel.h"
  52 #include "symtab.h"
  53 #include "tables.h"
  54 #include "uniqstr.h"
  55
  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   atexit (close_stdout);
  68
  69   uniqstrs_new ();
  70   muscle_init ();
  71
  72   getargs (argc, argv);
  73
  74   timevar_report = trace_flag & trace_time;
  75   init_timevar ();
  76   timevar_start (TV_TOTAL);
  77
  78   if (trace_flag & trace_bitsets)
  79     bitset_stats_enable ();
  80
  81   /* Read the input.  Copy some parts of it to FGUARD, FACTION, FTABLE
  82      and FATTRS.  In file reader.c.  The other parts are recorded in
  83      the grammar; see gram.h.  */
  84
  85   timevar_push (TV_READER);
  86   reader ();
  87   timevar_pop (TV_READER);
  88
  89   if (complaint_issued)
  90     goto finish;
  91
  92   /* Find useless nonterminals and productions and reduce the grammar. */
  93   timevar_push (TV_REDUCE);
  94   reduce_grammar ();
  95   timevar_pop (TV_REDUCE);
  96
  97   /* Record other info about the grammar.  In files derives and
  98      nullable.  */
  99   timevar_push (TV_SETS);
 100   derives_compute ();
 101   nullable_compute ();
 102   timevar_pop (TV_SETS);
 103
 104   /* Compute LR(0) parser states.  See state.h for more info.  */
 105   timevar_push (TV_LR0);
 106   generate_states ();
 107   timevar_pop (TV_LR0);
 108
 109   /* Add lookahead sets to parser states.  Except when LALR(1) is
 110      requested, split states to eliminate LR(1)-relative
 111      inadequacies.  */
 112   ielr ();
 113
 114   /* Find and record any conflicts: places where one token of
 115      lookahead is not enough to disambiguate the parsing.  In file
 116      conflicts.  Also resolve s/r conflicts based on precedence
 117      declarations.  */
 118   timevar_push (TV_CONFLICTS);
 119   conflicts_solve ();
 120   if (!muscle_percent_define_flag_if ("lr.keep-unreachable-states"))
 121     {
 122       state_number *old_to_new = xnmalloc (nstates, sizeof *old_to_new);
 123       state_number nstates_old = nstates;
 124       state_remove_unreachable_states (old_to_new);
 125       lalr_update_state_numbers (old_to_new, nstates_old);
 126       conflicts_update_state_numbers (old_to_new, nstates_old);
 127       free (old_to_new);
 128     }
 129   conflicts_print ();
 130   timevar_pop (TV_CONFLICTS);
 131
 132   /* Compute the parser tables.  */
 133   timevar_push (TV_ACTIONS);
 134   tables_generate ();
 135   timevar_pop (TV_ACTIONS);
 136
 137   grammar_rules_useless_report
 138     (_("rule useless in parser due to conflicts"));
 139
 140   /* Output file names. */
 141   compute_output_file_names ();
 142
 143   /* Output the detailed report on the grammar.  */
 144   if (report_flag)
 145     {
 146       timevar_push (TV_REPORT);
 147       print_results ();
 148       timevar_pop (TV_REPORT);
 149     }
 150
 151   /* Output the graph.  */
 152   if (graph_flag)
 153     {
 154       timevar_push (TV_GRAPH);
 155       print_graph ();
 156       timevar_pop (TV_GRAPH);
 157     }
 158
 159   /* Output xml.  */
 160   if (xml_flag)
 161     {
 162       timevar_push (TV_XML);
 163       print_xml ();
 164       timevar_pop (TV_XML);
 165     }
 166
 167   /* Stop if there were errors, to avoid trashing previous output
 168      files.  */
 169   if (complaint_issued)
 170     goto finish;
 171
 172   /* Lookahead tokens are no longer needed. */
 173   timevar_push (TV_FREE);
 174   lalr_free ();
 175   timevar_pop (TV_FREE);
 176
 177   /* Output the tables and the parser to ftable.  In file output.  */
 178   timevar_push (TV_PARSER);
 179   output ();
 180   timevar_pop (TV_PARSER);
 181
 182   timevar_push (TV_FREE);
 183   nullable_free ();
 184   derives_free ();
 185   tables_free ();
 186   states_free ();
 187   reduce_free ();
 188   conflicts_free ();
 189   grammar_free ();
 190   output_file_names_free ();
 191
 192   /* The scanner memory cannot be released right after parsing, as it
 193      contains things such as user actions, prologue, epilogue etc.  */
 194   gram_scanner_free ();
 195   muscle_free ();
 196   uniqstrs_free ();
 197   code_scanner_free ();
 198   skel_scanner_free ();
 199   quotearg_free ();
 200   timevar_pop (TV_FREE);
 201
 202   if (trace_flag & trace_bitsets)
 203     bitset_stats_dump (stderr);
 204
 205  finish:
 206
 207   /* Stop timing and print the times.  */
 208   timevar_stop (TV_TOTAL);
 209   timevar_print (stderr);
 210
 211   return complaint_issued ? EXIT_FAILURE : EXIT_SUCCESS;
 212 }