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   getargs (argc, argv);
  59
  60   time_report = trace_flag & trace_time;
  61   init_timevar ();
  62   timevar_start (TV_TOTAL);
  63
  64   if (trace_flag & trace_bitsets)
  65     bitset_stats_enable ();
  66
  67   struniqs_new ();
  68   muscle_init ();
  69
  70   /* Read the input.  Copy some parts of it to FGUARD, FACTION, FTABLE
  71      and FATTRS.  In file reader.c.  The other parts are recorded in
  72      the grammar; see gram.h.  */
  73
  74   timevar_push (TV_READER);
  75   reader ();
  76   timevar_pop (TV_READER);
  77
  78   if (complaint_issued)
  79     goto finish;
  80
  81   /* Find useless nonterminals and productions and reduce the grammar. */
  82   timevar_push (TV_REDUCE);
  83   reduce_grammar ();
  84   timevar_pop (TV_REDUCE);
  85
  86   /* Record other info about the grammar.  In files derives and
  87      nullable.  */
  88   timevar_push (TV_SETS);
  89   derives_compute ();
  90   nullable_compute ();
  91   timevar_pop (TV_SETS);
  92
  93   /* Convert to nondeterministic finite state machine.  In file LR0.
  94      See state.h for more info.  */
  95   timevar_push (TV_LR0);
  96   generate_states ();
  97   timevar_pop (TV_LR0);
  98
  99   /* make it deterministic.  In file lalr.  */
 100   timevar_push (TV_LALR);
 101   lalr ();
 102   timevar_pop (TV_LALR);
 103
 104   /* Find and record any conflicts: places where one token of
 105      lookahead is not enough to disambiguate the parsing.  In file
 106      conflicts.  Also resolve s/r conflicts based on precedence
 107      declarations.  */
 108   timevar_push (TV_CONFLICTS);
 109   conflicts_solve ();
 110   conflicts_print ();
 111   timevar_pop (TV_CONFLICTS);
 112
 113   /* Compute the parser tables.  */
 114   timevar_push (TV_ACTIONS);
 115   tables_generate ();
 116   timevar_pop (TV_ACTIONS);
 117
 118   grammar_rules_never_reduced_report
 119     (_("rule never reduced because of conflicts"));
 120
 121   /* Output file names. */
 122   compute_output_file_names ();
 123
 124   /* Output the detailed report on the grammar.  */
 125   if (report_flag)
 126     {
 127       timevar_push (TV_REPORT);
 128       print_results ();
 129       timevar_pop (TV_REPORT);
 130     }
 131
 132   /* Output the VCG graph.  */
 133   if (graph_flag)
 134     {
 135       timevar_push (TV_GRAPH);
 136       print_graph ();
 137       timevar_pop (TV_GRAPH);
 138     }
 139
 140   /* Stop if there were errors, to avoid trashing previous output
 141      files.  */
 142   if (complaint_issued)
 143     goto finish;
 144
 145   /* Lookaheads are no longer needed. */
 146   timevar_push (TV_FREE);
 147   lalr_free ();
 148   timevar_pop (TV_FREE);
 149
 150   /* Output the tables and the parser to ftable.  In file output.  */
 151   timevar_push (TV_PARSER);
 152   output ();
 153   timevar_pop (TV_PARSER);
 154
 155   timevar_push (TV_FREE);
 156   nullable_free ();
 157   derives_free ();
 158   tables_free ();
 159   states_free ();
 160   reduce_free ();
 161   conflicts_free ();
 162   grammar_free ();
 163   /* FIXME: We are leaking all the other file names.  */
 164   free (infile);
 165
 166   /* The scanner memory cannot be released right after parsing, as it
 167      contains things such as user actions, prologue, epilogue etc.  */
 168   scanner_free ();
 169   muscle_free ();
 170   struniqs_free ();
 171   /* If using alloca.c, flush the alloca'ed memory for the benefit of
 172      people running Bison as a library in IDEs.  */
 173 #if C_ALLOCA
 174   alloca (0);
 175 #endif
 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 }