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
  25 #include <bitset_stats.h>
  26 #include <bitset.h>
  27 #include <timevar.h>
  28
  29 #include "LR0.h"
  30 #include "complain.h"
  31 #include "conflicts.h"
  32 #include "derives.h"
  33 #include "files.h"
  34 #include "getargs.h"
  35 #include "gram.h"
  36 #include "lalr.h"
  37 #include "muscle_tab.h"
  38 #include "nullable.h"
  39 #include "output.h"
  40 #include "print.h"
  41 #include "print_graph.h"
  42 #include "reader.h"
  43 #include "reduce.h"
  44 #include "symtab.h"
  45 #include "tables.h"
  46 #include "uniqstr.h"
  47
  48 /* The name this program was run with, for messages.  */
  49 char *program_name;
  50
  51
  52
  53 int
  54 main (int argc, char *argv[])
  55 {
  56   program_name = argv[0];
  57   setlocale (LC_ALL, "");
  58   (void) bindtextdomain (PACKAGE, LOCALEDIR);
  59   (void) textdomain (PACKAGE);
  60
  61   uniqstrs_new ();
  62
  63   getargs (argc, argv);
  64
  65   timevar_report = trace_flag & trace_time;
  66   init_timevar ();
  67   timevar_start (TV_TOTAL);
  68
  69   if (trace_flag & trace_bitsets)
  70     bitset_stats_enable ();
  71
  72   muscle_init ();
  73
  74   /* Read the input.  Copy some parts of it to FGUARD, FACTION, FTABLE
  75      and FATTRS.  In file reader.c.  The other parts are recorded in
  76      the grammar; see gram.h.  */
  77
  78   timevar_push (TV_READER);
  79   reader ();
  80   timevar_pop (TV_READER);
  81
  82   if (complaint_issued)
  83     goto finish;
  84
  85   /* Find useless nonterminals and productions and reduce the grammar. */
  86   timevar_push (TV_REDUCE);
  87   reduce_grammar ();
  88   timevar_pop (TV_REDUCE);
  89
  90   /* Record other info about the grammar.  In files derives and
  91      nullable.  */
  92   timevar_push (TV_SETS);
  93   derives_compute ();
  94   nullable_compute ();
  95   timevar_pop (TV_SETS);
  96
  97   /* Convert to nondeterministic finite state machine.  In file LR0.
  98      See state.h for more info.  */
  99   timevar_push (TV_LR0);
 100   generate_states ();
 101   timevar_pop (TV_LR0);
 102
 103   /* make it deterministic.  In file lalr.  */
 104   timevar_push (TV_LALR);
 105   lalr ();
 106   timevar_pop (TV_LALR);
 107
 108   /* Find and record any conflicts: places where one token of
 109      lookahead is not enough to disambiguate the parsing.  In file
 110      conflicts.  Also resolve s/r conflicts based on precedence
 111      declarations.  */
 112   timevar_push (TV_CONFLICTS);
 113   conflicts_solve ();
 114   conflicts_print ();
 115   timevar_pop (TV_CONFLICTS);
 116
 117   /* Compute the parser tables.  */
 118   timevar_push (TV_ACTIONS);
 119   tables_generate ();
 120   timevar_pop (TV_ACTIONS);
 121
 122   grammar_rules_never_reduced_report
 123     (_("rule never reduced because of conflicts"));
 124
 125   /* Output file names. */
 126   compute_output_file_names ();
 127
 128   /* Output the detailed report on the grammar.  */
 129   if (report_flag)
 130     {
 131       timevar_push (TV_REPORT);
 132       print_results ();
 133       timevar_pop (TV_REPORT);
 134     }
 135
 136   /* Output the VCG graph.  */
 137   if (graph_flag)
 138     {
 139       timevar_push (TV_GRAPH);
 140       print_graph ();
 141       timevar_pop (TV_GRAPH);
 142     }
 143
 144   /* Stop if there were errors, to avoid trashing previous output
 145      files.  */
 146   if (complaint_issued)
 147     goto finish;
 148
 149   /* Lookaheads are no longer needed. */
 150   timevar_push (TV_FREE);
 151   lalr_free ();
 152   timevar_pop (TV_FREE);
 153
 154   /* Output the tables and the parser to ftable.  In file output.  */
 155   timevar_push (TV_PARSER);
 156   output ();
 157   timevar_pop (TV_PARSER);
 158
 159   timevar_push (TV_FREE);
 160   nullable_free ();
 161   derives_free ();
 162   tables_free ();
 163   states_free ();
 164   reduce_free ();
 165   conflicts_free ();
 166   grammar_free ();
 167
 168   /* The scanner memory cannot be released right after parsing, as it
 169      contains things such as user actions, prologue, epilogue etc.  */
 170   scanner_free ();
 171   muscle_free ();
 172   uniqstrs_free ();
 173   /* If using alloca.c, flush the alloca'ed memory for the benefit of
 174      people running Bison as a library in IDEs.  */
 175 #if C_ALLOCA
 176   alloca (0);
 177 #endif
 178   timevar_pop (TV_FREE);
 179
 180   if (trace_flag & trace_bitsets)
 181     bitset_stats_dump (stderr);
 182
 183  finish:
 184
 185   /* Stop timing and print the times.  */
 186   timevar_stop (TV_TOTAL);
 187   timevar_print (stderr);
 188
 189   return complaint_issued ? EXIT_FAILURE : EXIT_SUCCESS;
 190 }