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    Free Software Foundation, Inc.
   5
   6    This file is part of Bison, the GNU Compiler Compiler.
   7
   8    Bison 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 2, or (at your option)
  11    any later version.
  12
  13    Bison 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 Bison; see the file COPYING.  If not, write to
  20    the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  21    Boston, MA 02110-1301, USA.  */
  22
  23
  24 #include "system.h"
  25
  26 #include <bitset_stats.h>
  27 #include <bitset.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 "reader.h"
  44 #include "reduce.h"
  45 #include "symtab.h"
  46 #include "tables.h"
  47 #include "uniqstr.h"
  48
  49 /* The name this program was run with, for messages.  */
  50 char *program_name;
  51
  52
  53
  54 int
  55 main (int argc, char *argv[])
  56 {
  57   program_name = argv[0];
  58   setlocale (LC_ALL, "");
  59   (void) bindtextdomain (PACKAGE, LOCALEDIR);
  60   (void) bindtextdomain ("bison-runtime", LOCALEDIR);
  61   (void) textdomain (PACKAGE);
  62
  63   uniqstrs_new ();
  64
  65   getargs (argc, argv);
  66
  67   timevar_report = trace_flag & trace_time;
  68   init_timevar ();
  69   timevar_start (TV_TOTAL);
  70
  71   if (trace_flag & trace_bitsets)
  72     bitset_stats_enable ();
  73
  74   muscle_init ();
  75
  76   /* Read the input.  Copy some parts of it to FGUARD, FACTION, FTABLE
  77      and FATTRS.  In file reader.c.  The other parts are recorded in
  78      the grammar; see gram.h.  */
  79
  80   timevar_push (TV_READER);
  81   reader ();
  82   timevar_pop (TV_READER);
  83
  84   if (complaint_issued)
  85     goto finish;
  86
  87   /* Find useless nonterminals and productions and reduce the grammar. */
  88   timevar_push (TV_REDUCE);
  89   reduce_grammar ();
  90   timevar_pop (TV_REDUCE);
  91
  92   /* Record other info about the grammar.  In files derives and
  93      nullable.  */
  94   timevar_push (TV_SETS);
  95   derives_compute ();
  96   nullable_compute ();
  97   timevar_pop (TV_SETS);
  98
  99   /* Convert to nondeterministic finite state machine.  In file LR0.
 100      See state.h for more info.  */
 101   timevar_push (TV_LR0);
 102   generate_states ();
 103   timevar_pop (TV_LR0);
 104
 105   /* make it deterministic.  In file lalr.  */
 106   timevar_push (TV_LALR);
 107   lalr ();
 108   timevar_pop (TV_LALR);
 109
 110   /* Find and record any conflicts: places where one token of
 111      look-ahead is not enough to disambiguate the parsing.  In file
 112      conflicts.  Also resolve s/r conflicts based on precedence
 113      declarations.  */
 114   timevar_push (TV_CONFLICTS);
 115   conflicts_solve ();
 116   conflicts_print ();
 117   timevar_pop (TV_CONFLICTS);
 118
 119   /* Compute the parser tables.  */
 120   timevar_push (TV_ACTIONS);
 121   tables_generate ();
 122   timevar_pop (TV_ACTIONS);
 123
 124   grammar_rules_never_reduced_report
 125     (_("rule never reduced because of conflicts"));
 126
 127   /* Output file names. */
 128   compute_output_file_names ();
 129
 130   /* Output the detailed report on the grammar.  */
 131   if (report_flag)
 132     {
 133       timevar_push (TV_REPORT);
 134       print_results ();
 135       timevar_pop (TV_REPORT);
 136     }
 137
 138   /* Output the VCG graph.  */
 139   if (graph_flag)
 140     {
 141       timevar_push (TV_GRAPH);
 142       print_graph ();
 143       timevar_pop (TV_GRAPH);
 144     }
 145
 146   /* Stop if there were errors, to avoid trashing previous output
 147      files.  */
 148   if (complaint_issued)
 149     goto finish;
 150
 151   /* Look-ahead tokens are no longer needed. */
 152   timevar_push (TV_FREE);
 153   lalr_free ();
 154   timevar_pop (TV_FREE);
 155
 156   /* Output the tables and the parser to ftable.  In file output.  */
 157   timevar_push (TV_PARSER);
 158   output ();
 159   timevar_pop (TV_PARSER);
 160
 161   timevar_push (TV_FREE);
 162   nullable_free ();
 163   derives_free ();
 164   tables_free ();
 165   states_free ();
 166   reduce_free ();
 167   conflicts_free ();
 168   grammar_free ();
 169
 170   /* The scanner memory cannot be released right after parsing, as it
 171      contains things such as user actions, prologue, epilogue etc.  */
 172   scanner_free ();
 173   muscle_free ();
 174   uniqstrs_free ();
 175   /* If using alloca.c, flush the alloca'ed memory for the benefit of
 176      people running Bison as a library in IDEs.  */
 177 #if C_ALLOCA
 178   {
 179     extern void *alloca (size_t);
 180     alloca (0);
 181   }
 182 #endif
 183   timevar_pop (TV_FREE);
 184
 185   if (trace_flag & trace_bitsets)
 186     bitset_stats_dump (stderr);
 187
 188  finish:
 189
 190   /* Stop timing and print the times.  */
 191   timevar_stop (TV_TOTAL);
 192   timevar_print (stderr);
 193
 194   return complaint_issued ? EXIT_FAILURE : EXIT_SUCCESS;
 195 }