src/print_graph.c

   1 /* Output a VCG description on generated parser, for Bison,
   2
   3    Copyright (C) 2001, 2002, 2003, 2004, 2005 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., 51 Franklin Street, Fifth Floor,
  20    Boston, MA 02110-1301, USA.  */
  21
  22 #include <config.h>
  23 #include "system.h"
  24
  25 #include <quotearg.h>
  26
  27 #include "LR0.h"
  28 #include "closure.h"
  29 #include "complain.h"
  30 #include "conflicts.h"
  31 #include "files.h"
  32 #include "getargs.h"
  33 #include "gram.h"
  34 #include "lalr.h"
  35 #include "print_graph.h"
  36 #include "reader.h"
  37 #include "state.h"
  38 #include "symtab.h"
  39 #include "vcg.h"
  40
  41 static graph static_graph;
  42 static FILE *fgraph = NULL;
  43
  44
  45 /*----------------------------.
  46 | Construct the node labels.  |
  47 `----------------------------*/
  48
  49 static void
  50 print_core (struct obstack *oout, state *s)
  51 {
  52   size_t i;
  53   item_number *sitems = s->items;
  54   size_t snritems = s->nitems;
  55
  56   /* Output all the items of a state, not only its kernel.  */
  57   if (report_flag & report_itemsets)
  58     {
  59       closure (sitems, snritems);
  60       sitems = itemset;
  61       snritems = nritemset;
  62     }
  63
  64   obstack_fgrow1 (oout, "state %2d\n", s->number);
  65   for (i = 0; i < snritems; i++)
  66     {
  67       item_number *sp;
  68       item_number *sp1;
  69       rule_number r;
  70
  71       sp1 = sp = ritem + sitems[i];
  72
  73       while (*sp >= 0)
  74         sp++;
  75
  76       r = item_number_as_rule_number (*sp);
  77
  78       if (i)
  79         obstack_1grow (oout, '\n');
  80       obstack_fgrow1 (oout, " %s -> ",
  81                       rules[r].lhs->tag);
  82
  83       for (sp = rules[r].rhs; sp < sp1; sp++)
  84         obstack_fgrow1 (oout, "%s ", symbols[*sp]->tag);
  85
  86       obstack_1grow (oout, '.');
  87
  88       for (/* Nothing */; *sp >= 0; ++sp)
  89         obstack_fgrow1 (oout, " %s", symbols[*sp]->tag);
  90
  91       /* Experimental feature: display the look-ahead tokens. */
  92       if (report_flag & report_look_ahead_tokens)
  93         {
  94           /* Find the reduction we are handling.  */
  95           reductions *reds = s->reductions;
  96           int redno = state_reduction_find (s, &rules[r]);
  97
  98           /* Print them if there are.  */
  99           if (reds->look_ahead_tokens && redno != -1)
 100             {
 101               bitset_iterator biter;
 102               int k;
 103               char const *sep = "";
 104               obstack_sgrow (oout, "[");
 105               BITSET_FOR_EACH (biter, reds->look_ahead_tokens[redno], k, 0)
 106                 {
 107                   obstack_fgrow2 (oout, "%s%s", sep, symbols[k]->tag);
 108                   sep = ", ";
 109                 }
 110               obstack_sgrow (oout, "]");
 111             }
 112         }
 113     }
 114 }
 115
 116
 117 /*---------------------------------------------------------------.
 118 | Output in graph_obstack edges specifications in incidence with |
 119 | current node.                                                  |
 120 `---------------------------------------------------------------*/
 121
 122 static void
 123 print_actions (state *s, const char *node_name)
 124 {
 125   int i;
 126
 127   transitions *trans = s->transitions;
 128   reductions *reds = s->reductions;
 129
 130   static char buff[10];
 131   edge e;
 132
 133   if (!trans->num && !reds)
 134     return;
 135
 136   for (i = 0; i < trans->num; i++)
 137     if (!TRANSITION_IS_DISABLED (trans, i))
 138       {
 139         state *s1 = trans->states[i];
 140         symbol_number sym = s1->accessing_symbol;
 141
 142         new_edge (&e);
 143
 144         if (s->number > s1->number)
 145           e.type = back_edge;
 146         open_edge (&e, fgraph);
 147         /* The edge source is the current node.  */
 148         e.sourcename = node_name;
 149         sprintf (buff, "%d", s1->number);
 150         e.targetname = buff;
 151         /* Shifts are blue, gotos are green, and error is red. */
 152         if (TRANSITION_IS_ERROR (trans, i))
 153           e.color = red;
 154         else
 155           e.color = TRANSITION_IS_SHIFT (trans, i) ? blue : green;
 156         e.label = symbols[sym]->tag;
 157         output_edge (&e, fgraph);
 158         close_edge (fgraph);
 159       }
 160 }
 161
 162
 163 /*-------------------------------------------------------------.
 164 | Output in FGRAPH the current node specifications and exiting |
 165 | edges.                                                       |
 166 `-------------------------------------------------------------*/
 167
 168 static void
 169 print_state (state *s)
 170 {
 171   static char name[10];
 172   struct obstack node_obstack;
 173   node n;
 174
 175   /* The labels of the nodes are their the items.  */
 176   obstack_init (&node_obstack);
 177   new_node (&n);
 178   sprintf (name, "%d", s->number);
 179   n.title = name;
 180   print_core (&node_obstack, s);
 181   obstack_1grow (&node_obstack, '\0');
 182   n.label = obstack_finish (&node_obstack);
 183
 184   open_node (fgraph);
 185   output_node (&n, fgraph);
 186   close_node (fgraph);
 187
 188   /* Output the edges.  */
 189   print_actions (s, name);
 190
 191   obstack_free (&node_obstack, 0);
 192 }
 193 \f
 194
 195 void
 196 print_graph (void)
 197 {
 198   state_number i;
 199
 200   /* Output file.  */
 201   fgraph = xfopen (spec_graph_file, "w");
 202
 203   new_graph (&static_graph);
 204
 205   static_graph.display_edge_labels = yes;
 206
 207   static_graph.port_sharing = no;
 208   static_graph.finetuning = yes;
 209   static_graph.priority_phase = yes;
 210   static_graph.splines = yes;
 211
 212   static_graph.crossing_weight = median;
 213
 214   /* Output graph options. */
 215   open_graph (fgraph);
 216   output_graph (&static_graph, fgraph);
 217
 218   /* Output nodes and edges. */
 219   new_closure (nritems);
 220   for (i = 0; i < nstates; i++)
 221     print_state (states[i]);
 222   free_closure ();
 223
 224   /* Close graph. */
 225   close_graph (&static_graph, fgraph);
 226   xfclose (fgraph);
 227 }