src/main.c

   1 /* Top level entry point of bison,
   2    Copyright 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 "symtab.h"
  28 #include "gram.h"
  29 #include "files.h"
  30 #include "complain.h"
  31 #include "derives.h"
  32 #include "output.h"
  33 #include "reader.h"
  34 #include "lalr.h"
  35 #include "reduce.h"
  36 #include "nullable.h"
  37 #include "print.h"
  38 #include "LR0.h"
  39 #include "conflicts.h"
  40 #include "print_graph.h"
  41 #include "muscle_tab.h"
  42
  43 /* The name this program was run with, for messages.  */
  44 char *program_name;
  45
  46
  47
  48 int
  49 main (int argc, char *argv[])
  50 {
  51   program_name = argv[0];
  52   setlocale (LC_ALL, "");
  53   bindtextdomain (PACKAGE, LOCALEDIR);
  54   textdomain (PACKAGE);
  55
  56   getargs (argc, argv);
  57
  58   time_report = trace_flag & trace_time;
  59   init_timevar ();
  60   timevar_start (TV_TOTAL);
  61
  62   if (trace_flag & trace_bitsets)
  63     bitset_stats_enable ();
  64
  65   muscle_init ();
  66
  67   /* Read the input.  Copy some parts of it to FGUARD, FACTION, FTABLE
  68      and FATTRS.  In file reader.c.  The other parts are recorded in
  69      the grammar; see gram.h.  */
  70
  71   timevar_push (TV_READER);
  72   reader ();
  73   timevar_pop (TV_READER);
  74
  75   if (complain_message_count)
  76     exit (1);
  77
  78   /* Find useless nonterminals and productions and reduce the grammar. */
  79   timevar_push (TV_REDUCE);
  80   reduce_grammar ();
  81   timevar_pop (TV_REDUCE);
  82
  83   /* Record other info about the grammar.  In files derives and
  84      nullable.  */
  85   timevar_push (TV_SETS);
  86   set_derives ();
  87   set_nullable ();
  88   timevar_pop (TV_SETS);
  89
  90   /* Convert to nondeterministic finite state machine.  In file LR0.
  91      See state.h for more info.  */
  92   timevar_push (TV_LR0);
  93   generate_states ();
  94   timevar_pop (TV_LR0);
  95
  96   /* make it deterministic.  In file lalr.  */
  97   timevar_push (TV_LALR);
  98   lalr ();
  99   timevar_pop (TV_LALR);
 100
 101   /* Find and record any conflicts: places where one token of
 102      lookahead is not enough to disambiguate the parsing.  In file
 103      conflicts.  Also resolve s/r conflicts based on precedence
 104      declarations.  */
 105   timevar_push (TV_CONFLICTS);
 106   conflicts_solve ();
 107   conflicts_print ();
 108   timevar_pop (TV_CONFLICTS);
 109
 110   /* Output file names. */
 111   compute_output_file_names ();
 112
 113   /* Output the detailed report on the grammar.  */
 114   if (report_flag)
 115     {
 116       timevar_push (TV_REPORT);
 117       print_results ();
 118       timevar_pop (TV_REPORT);
 119     }
 120
 121   /* Stop if there were errors, to avoid trashing previous output
 122      files.  */
 123   if (complain_message_count)
 124     exit (1);
 125
 126   /* Output the VCG graph.  */
 127   if (graph_flag)
 128     {
 129       timevar_push (TV_GRAPH);
 130       print_graph ();
 131       timevar_pop (TV_GRAPH);
 132     }
 133
 134   /* Output the tables and the parser to ftable.  In file output.  */
 135   timevar_push (TV_PARSER);
 136   output ();
 137   timevar_pop (TV_PARSER);
 138
 139   timevar_push (TV_FREE);
 140   states_free ();
 141   reduce_free ();
 142   conflicts_free ();
 143   free_nullable ();
 144   free_derives ();
 145   grammar_free ();
 146
 147   /* The scanner memory cannot be released right after parsing, as it
 148      contains things such as user actions, prologue, epilogue etc.  */
 149   scanner_free ();
 150   muscle_free ();
 151   /* If using alloca.c, flush the alloca'ed memory for the benefit of
 152      people running Bison as a library in IDEs.  */
 153 #if C_ALLOCA
 154   alloca (0);
 155 #endif
 156   timevar_pop (TV_FREE);
 157
 158   if (trace_flag & trace_bitsets)
 159     bitset_stats_dump (stderr);
 160
 161   /* Stop timing and print the times.  */
 162   timevar_stop (TV_TOTAL);
 163   timevar_print (stderr);
 164
 165   return complain_message_count ? EXIT_FAILURE : EXIT_SUCCESS;
 166 }