src/main.c

   1 /* Top level entry point of Bison.
   2
   3    Copyright (C) 1984, 1986, 1989, 1992, 1995, 2000, 2001, 2002, 2004, 2005,
   4    2006
   5    Free Software Foundation, Inc.
   6
   7    This file is part of Bison, the GNU Compiler Compiler.
   8
   9    Bison is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 2, or (at your option)
  12    any later version.
  13
  14    Bison is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with Bison; see the file COPYING.  If not, write to
  21    the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  22    Boston, MA 02110-1301, USA.  */
  23
  24 #include <config.h>
  25 #include "system.h"
  26
  27 #include <bitset_stats.h>
  28 #include <bitset.h>
  29 #include <timevar.h>
  30
  31 #include "LR0.h"
  32 #include "complain.h"
  33 #include "conflicts.h"
  34 #include "derives.h"
  35 #include "files.h"
  36 #include "getargs.h"
  37 #include "gram.h"
  38 #include "lalr.h"
  39 #include "muscle_tab.h"
  40 #include "nullable.h"
  41 #include "output.h"
  42 #include "print.h"
  43 #include "print_graph.h"
  44 #include "reader.h"
  45 #include "reduce.h"
  46 #include "symtab.h"
  47 #include "tables.h"
  48 #include "uniqstr.h"
  49
  50 /* The name this program was run with, for messages.  */
  51 char *program_name;
  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      look-ahead 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   conflicts_print ();
 118   timevar_pop (TV_CONFLICTS);
 119
 120   /* Compute the parser tables.  */
 121   timevar_push (TV_ACTIONS);
 122   tables_generate ();
 123   timevar_pop (TV_ACTIONS);
 124
 125   grammar_rules_never_reduced_report
 126     (_("rule never reduced because of conflicts"));
 127
 128   /* Output file names. */
 129   compute_output_file_names ();
 130
 131   /* Output the detailed report on the grammar.  */
 132   if (report_flag)
 133     {
 134       timevar_push (TV_REPORT);
 135       print_results ();
 136       timevar_pop (TV_REPORT);
 137     }
 138
 139   /* Output the VCG graph.  */
 140   if (graph_flag)
 141     {
 142       timevar_push (TV_GRAPH);
 143       print_graph ();
 144       timevar_pop (TV_GRAPH);
 145     }
 146
 147   /* Stop if there were errors, to avoid trashing previous output
 148      files.  */
 149   if (complaint_issued)
 150     goto finish;
 151
 152   /* Look-ahead tokens are no longer needed. */
 153   timevar_push (TV_FREE);
 154   lalr_free ();
 155   timevar_pop (TV_FREE);
 156
 157   /* Output the tables and the parser to ftable.  In file output.  */
 158   timevar_push (TV_PARSER);
 159   output ();
 160   timevar_pop (TV_PARSER);
 161
 162   timevar_push (TV_FREE);
 163   nullable_free ();
 164   derives_free ();
 165   tables_free ();
 166   states_free ();
 167   reduce_free ();
 168   conflicts_free ();
 169   grammar_free ();
 170
 171   /* The scanner memory cannot be released right after parsing, as it
 172      contains things such as user actions, prologue, epilogue etc.  */
 173   gram_scanner_free ();
 174   muscle_free ();
 175   uniqstrs_free ();
 176   timevar_pop (TV_FREE);
 177
 178   if (trace_flag & trace_bitsets)
 179     bitset_stats_dump (stderr);
 180
 181  finish:
 182
 183   /* Stop timing and print the times.  */
 184   timevar_stop (TV_TOTAL);
 185   timevar_print (stderr);
 186
 187   return complaint_issued ? EXIT_FAILURE : EXIT_SUCCESS;
 188 }