src/main.c

   1 /* Top level entry point of bison,
   2    Copyright (C) 1984, 1986, 1989, 1992, 1995, 2000, 2001, 2002
   3    Free Software Foundation, Inc.
   4
   5    This file is part of Bison, the GNU Compiler Compiler.
   6
   7    Bison is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 2, or (at your option)
  10    any later version.
  11
  12    Bison is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with Bison; see the file COPYING.  If not, write to
  19    the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  20    Boston, MA 02111-1307, USA.  */
  21
  22
  23 #include "system.h"
  24 #include "bitset_stats.h"
  25 #include "bitset.h"
  26 #include "getargs.h"
  27 #include "struniq.h"
  28 #include "symtab.h"
  29 #include "gram.h"
  30 #include "files.h"
  31 #include "complain.h"
  32 #include "derives.h"
  33 #include "tables.h"
  34 #include "output.h"
  35 #include "reader.h"
  36 #include "lalr.h"
  37 #include "reduce.h"
  38 #include "nullable.h"
  39 #include "print.h"
  40 #include "LR0.h"
  41 #include "conflicts.h"
  42 #include "print_graph.h"
  43 #include "muscle_tab.h"
  44
  45 /* The name this program was run with, for messages.  */
  46 char *program_name;
  47
  48
  49
  50 int
  51 main (int argc, char *argv[])
  52 {
  53   program_name = argv[0];
  54   setlocale (LC_ALL, "");
  55   (void) bindtextdomain (PACKAGE, LOCALEDIR);
  56   (void) textdomain (PACKAGE);
  57
  58   struniqs_new ();
  59
  60   getargs (argc, argv);
  61
  62   time_report = trace_flag & trace_time;
  63   init_timevar ();
  64   timevar_start (TV_TOTAL);
  65
  66   if (trace_flag & trace_bitsets)
  67     bitset_stats_enable ();
  68
  69   muscle_init ();
  70
  71   /* Read the input.  Copy some parts of it to FGUARD, FACTION, FTABLE
  72      and FATTRS.  In file reader.c.  The other parts are recorded in
  73      the grammar; see gram.h.  */
  74
  75   timevar_push (TV_READER);
  76   reader ();
  77   timevar_pop (TV_READER);
  78
  79   if (complaint_issued)
  80     goto finish;
  81
  82   /* Find useless nonterminals and productions and reduce the grammar. */
  83   timevar_push (TV_REDUCE);
  84   reduce_grammar ();
  85   timevar_pop (TV_REDUCE);
  86
  87   /* Record other info about the grammar.  In files derives and
  88      nullable.  */
  89   timevar_push (TV_SETS);
  90   derives_compute ();
  91   nullable_compute ();
  92   timevar_pop (TV_SETS);
  93
  94   /* Convert to nondeterministic finite state machine.  In file LR0.
  95      See state.h for more info.  */
  96   timevar_push (TV_LR0);
  97   generate_states ();
  98   timevar_pop (TV_LR0);
  99
 100   /* make it deterministic.  In file lalr.  */
 101   timevar_push (TV_LALR);
 102   lalr ();
 103   timevar_pop (TV_LALR);
 104
 105   /* Find and record any conflicts: places where one token of
 106      lookahead is not enough to disambiguate the parsing.  In file
 107      conflicts.  Also resolve s/r conflicts based on precedence
 108      declarations.  */
 109   timevar_push (TV_CONFLICTS);
 110   conflicts_solve ();
 111   conflicts_print ();
 112   timevar_pop (TV_CONFLICTS);
 113
 114   /* Compute the parser tables.  */
 115   timevar_push (TV_ACTIONS);
 116   tables_generate ();
 117   timevar_pop (TV_ACTIONS);
 118
 119   grammar_rules_never_reduced_report
 120     (_("rule never reduced because of conflicts"));
 121
 122   /* Output file names. */
 123   compute_output_file_names ();
 124
 125   /* Output the detailed report on the grammar.  */
 126   if (report_flag)
 127     {
 128       timevar_push (TV_REPORT);
 129       print_results ();
 130       timevar_pop (TV_REPORT);
 131     }
 132
 133   /* Output the VCG graph.  */
 134   if (graph_flag)
 135     {
 136       timevar_push (TV_GRAPH);
 137       print_graph ();
 138       timevar_pop (TV_GRAPH);
 139     }
 140
 141   /* Stop if there were errors, to avoid trashing previous output
 142      files.  */
 143   if (complaint_issued)
 144     goto finish;
 145
 146   /* Lookaheads are no longer needed. */
 147   timevar_push (TV_FREE);
 148   lalr_free ();
 149   timevar_pop (TV_FREE);
 150
 151   /* Output the tables and the parser to ftable.  In file output.  */
 152   timevar_push (TV_PARSER);
 153   output ();
 154   timevar_pop (TV_PARSER);
 155
 156   timevar_push (TV_FREE);
 157   nullable_free ();
 158   derives_free ();
 159   tables_free ();
 160   states_free ();
 161   reduce_free ();
 162   conflicts_free ();
 163   grammar_free ();
 164
 165   /* The scanner memory cannot be released right after parsing, as it
 166      contains things such as user actions, prologue, epilogue etc.  */
 167   scanner_free ();
 168   muscle_free ();
 169   struniqs_free ();
 170   /* If using alloca.c, flush the alloca'ed memory for the benefit of
 171      people running Bison as a library in IDEs.  */
 172 #if C_ALLOCA
 173   alloca (0);
 174 #endif
 175   timevar_pop (TV_FREE);
 176
 177   if (trace_flag & trace_bitsets)
 178     bitset_stats_dump (stderr);
 179
 180  finish:
 181
 182   /* Stop timing and print the times.  */
 183   timevar_stop (TV_TOTAL);
 184   timevar_print (stderr);
 185
 186   return complaint_issued ? EXIT_FAILURE : EXIT_SUCCESS;
 187 }