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 "print-xml.h"
  44 #include "reader.h"
  45 #include "reduce.h"
  46 #include "scan-code.h"
  47 #include "scan-gram.h"
  48 #include "scan-skel.h"
  49 #include "symtab.h"
  50 #include "tables.h"
  51 #include "uniqstr.h"
  52
  53
  54
  55 int
  56 main (int argc, char *argv[])
  57 {
  58   program_name = argv[0];
  59   setlocale (LC_ALL, "");
  60   (void) bindtextdomain (PACKAGE, LOCALEDIR);
  61   (void) bindtextdomain ("bison-runtime", LOCALEDIR);
  62   (void) textdomain (PACKAGE);
  63
  64   uniqstrs_new ();
  65
  66   getargs (argc, argv);
  67
  68   timevar_report = trace_flag & trace_time;
  69   init_timevar ();
  70   timevar_start (TV_TOTAL);
  71
  72   if (trace_flag & trace_bitsets)
  73     bitset_stats_enable ();
  74
  75   muscle_init ();
  76
  77   /* Read the input.  Copy some parts of it to FGUARD, FACTION, FTABLE
  78      and FATTRS.  In file reader.c.  The other parts are recorded in
  79      the grammar; see gram.h.  */
  80
  81   timevar_push (TV_READER);
  82   reader ();
  83   timevar_pop (TV_READER);
  84
  85   if (complaint_issued)
  86     goto finish;
  87
  88   /* Find useless nonterminals and productions and reduce the grammar. */
  89   timevar_push (TV_REDUCE);
  90   reduce_grammar ();
  91   timevar_pop (TV_REDUCE);
  92
  93   /* Record other info about the grammar.  In files derives and
  94      nullable.  */
  95   timevar_push (TV_SETS);
  96   derives_compute ();
  97   nullable_compute ();
  98   timevar_pop (TV_SETS);
  99
 100   /* Convert to nondeterministic finite state machine.  In file LR0.
 101      See state.h for more info.  */
 102   timevar_push (TV_LR0);
 103   generate_states ();
 104   timevar_pop (TV_LR0);
 105
 106   /* make it deterministic.  In file lalr.  */
 107   timevar_push (TV_LALR);
 108   lalr ();
 109   timevar_pop (TV_LALR);
 110
 111   /* Find and record any conflicts: places where one token of
 112      lookahead is not enough to disambiguate the parsing.  In file
 113      conflicts.  Also resolve s/r conflicts based on precedence
 114      declarations.  */
 115   timevar_push (TV_CONFLICTS);
 116   conflicts_solve ();
 117   muscle_percent_define_default ("lr.keep_unreachable_states", "false");
 118   if (!muscle_percent_define_flag_if ("lr.keep_unreachable_states"))
 119     {
 120       state_number *old_to_new = xnmalloc (nstates, sizeof *old_to_new);
 121       state_number nstates_old = nstates;
 122       state_remove_unreachable_states (old_to_new);
 123       lalr_update_state_numbers (old_to_new, nstates_old);
 124       conflicts_update_state_numbers (old_to_new, nstates_old);
 125       free (old_to_new);
 126     }
 127   conflicts_print ();
 128   timevar_pop (TV_CONFLICTS);
 129
 130   /* Compute the parser tables.  */
 131   timevar_push (TV_ACTIONS);
 132   tables_generate ();
 133   timevar_pop (TV_ACTIONS);
 134
 135   grammar_rules_never_reduced_report
 136     (_("rule never reduced because of conflicts"));
 137
 138   /* Output file names. */
 139   compute_output_file_names ();
 140
 141   /* Output the detailed report on the grammar.  */
 142   if (report_flag)
 143     {
 144       timevar_push (TV_REPORT);
 145       print_results ();
 146       timevar_pop (TV_REPORT);
 147     }
 148
 149   /* Output the graph.  */
 150   if (graph_flag)
 151     {
 152       timevar_push (TV_GRAPH);
 153       print_graph ();
 154       timevar_pop (TV_GRAPH);
 155     }
 156
 157   /* Output xml.  */
 158   if (xml_flag)
 159     {
 160       timevar_push (TV_XML);
 161       print_xml ();
 162       timevar_pop (TV_XML);
 163     }
 164
 165   /* Stop if there were errors, to avoid trashing previous output
 166      files.  */
 167   if (complaint_issued)
 168     goto finish;
 169
 170   /* Lookahead tokens are no longer needed. */
 171   timevar_push (TV_FREE);
 172   lalr_free ();
 173   timevar_pop (TV_FREE);
 174
 175   /* Output the tables and the parser to ftable.  In file output.  */
 176   timevar_push (TV_PARSER);
 177   output ();
 178   timevar_pop (TV_PARSER);
 179
 180   timevar_push (TV_FREE);
 181   nullable_free ();
 182   derives_free ();
 183   tables_free ();
 184   states_free ();
 185   reduce_free ();
 186   conflicts_free ();
 187   grammar_free ();
 188   output_file_names_free ();
 189
 190   /* The scanner memory cannot be released right after parsing, as it
 191      contains things such as user actions, prologue, epilogue etc.  */
 192   gram_scanner_free ();
 193   muscle_free ();
 194   uniqstrs_free ();
 195   code_scanner_free ();
 196   skel_scanner_free ();
 197   quotearg_free ();
 198   timevar_pop (TV_FREE);
 199
 200   if (trace_flag & trace_bitsets)
 201     bitset_stats_dump (stderr);
 202
 203  finish:
 204
 205   /* Stop timing and print the times.  */
 206   timevar_stop (TV_TOTAL);
 207   timevar_print (stderr);
 208
 209   return complaint_issued ? EXIT_FAILURE : EXIT_SUCCESS;
 210 }