src/print_graph.c

   1 /* Output a VCG description on generated parser, for Bison,
   2    Copyright 2001 Free Software Foundation, Inc.
   3
   4    This file is part of Bison, the GNU Compiler Compiler.
   5
   6    Bison is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 2, or (at your option)
   9    any later version.
  10
  11    Bison is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with Bison; see the file COPYING.  If not, write to
  18    the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  19    Boston, MA 02111-1307, USA.  */
  20
  21 #include "system.h"
  22 #include "quotearg.h"
  23 #include "files.h"
  24 #include "symtab.h"
  25 #include "gram.h"
  26 #include "LR0.h"
  27 #include "lalr.h"
  28 #include "conflicts.h"
  29 #include "complain.h"
  30 #include "getargs.h"
  31 #include "state.h"
  32 #include "reader.h"
  33 #include "closure.h"
  34 #include "obstack.h"
  35 #include "print_graph.h"
  36 #include "vcg.h"
  37
  38 static graph_t graph;
  39 static FILE *fgraph = NULL;
  40
  41
  42 /*----------------------------.
  43 | Construct the node labels.  |
  44 `----------------------------*/
  45
  46 static void
  47 print_core (struct obstack *oout, state_t *state)
  48 {
  49   int i;
  50   item_number_t *sitems = state->items;
  51   int snritems   = state->nitems;
  52
  53   /* Output all the items of a state, not only its kernel.  */
  54   if (report_flag & report_itemsets)
  55     {
  56       closure (sitems, snritems);
  57       sitems = itemset;
  58       snritems = nritemset;
  59     }
  60
  61   obstack_fgrow1 (oout, "state %2d\n", state->number);
  62   for (i = 0; i < snritems; i++)
  63     {
  64       item_number_t *sp;
  65       item_number_t *sp1;
  66       rule_number_t rule;
  67
  68       sp1 = sp = ritem + sitems[i];
  69
  70       while (*sp >= 0)
  71         sp++;
  72
  73       rule = rule_number_of_item_number (*sp);
  74
  75       if (i)
  76         obstack_1grow (oout, '\n');
  77       obstack_fgrow1 (oout, " %s -> ",
  78                       symbol_tag_get (rules[rule].lhs));
  79
  80       for (sp = rules[rule].rhs; sp < sp1; sp++)
  81         obstack_fgrow1 (oout, "%s ", symbol_tag_get (symbols[*sp]));
  82
  83       obstack_1grow (oout, '.');
  84
  85       for (/* Nothing */; *sp >= 0; ++sp)
  86         obstack_fgrow1 (oout, " %s", symbol_tag_get (symbols[*sp]));
  87
  88       /* Experimental feature: display the lookaheads. */
  89       if ((report_flag & report_lookaheads)
  90           && state->nlookaheads)
  91         {
  92           int j, k;
  93           int nlookaheads = 0;
  94           /* Look for lookaheads corresponding to this rule. */
  95           for (j = 0; j < state->nlookaheads; ++j)
  96             for (k = 0; k < ntokens; ++k)
  97               if (bitset_test (state->lookaheads[j], k)
  98                   && state->lookaheads_rule[j]->number == rule)
  99                 nlookaheads++;
 100           if (nlookaheads)
 101             {
 102               obstack_sgrow (oout, "  [");
 103               for (j = 0; j < state->nlookaheads; ++j)
 104                 for (k = 0; k < ntokens; ++k)
 105                   if (bitset_test (state->lookaheads[j], k)
 106                       && state->lookaheads_rule[j]->number == rule)
 107                     obstack_fgrow2 (oout, "%s%s",
 108                                     symbol_tag_get (symbols[k]),
 109                                     --nlookaheads ? ", " : "");
 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_t *state, const char *node_name)
 124 {
 125   int i;
 126
 127   shifts_t     *shiftp = state->shifts;
 128   reductions_t *redp = state->reductions;
 129
 130   static char buff[10];
 131   edge_t edge;
 132
 133   if (!shiftp->nshifts && !redp)
 134     return;
 135
 136   for (i = 0; i < shiftp->nshifts; i++)
 137     if (!SHIFT_IS_DISABLED (shiftp, i))
 138       {
 139         state_number_t state1 = shiftp->shifts[i];
 140         symbol_number_t symbol = states[state1]->accessing_symbol;
 141
 142         new_edge (&edge);
 143
 144         if (state->number > state1)
 145           edge.type = back_edge;
 146         open_edge (&edge, fgraph);
 147         /* The edge source is the current node.  */
 148         edge.sourcename = node_name;
 149         sprintf (buff, "%d", state1);
 150         edge.targetname = buff;
 151         /* Shifts are blue, gotos are green, and error is red. */
 152         if (SHIFT_IS_ERROR (shiftp, i))
 153           edge.color = red;
 154         else
 155           edge.color = SHIFT_IS_SHIFT(shiftp, i) ? blue : green;
 156         edge.label = symbol_tag_get (symbols[symbol]);
 157         output_edge (&edge, 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_t *state)
 170 {
 171   static char name[10];
 172   struct obstack node_obstack;
 173   node_t node;
 174
 175   /* The labels of the nodes are their the items.  */
 176   obstack_init (&node_obstack);
 177   new_node (&node);
 178   sprintf (name, "%d", state->number);
 179   node.title = name;
 180   print_core (&node_obstack, state);
 181   obstack_1grow (&node_obstack, '\0');
 182   node.label = obstack_finish (&node_obstack);
 183
 184   open_node (fgraph);
 185   output_node (&node, fgraph);
 186   close_node (fgraph);
 187
 188   /* Output the edges.  */
 189   print_actions (state, name);
 190
 191   obstack_free (&node_obstack, 0);
 192 }
 193 \f
 194
 195 void
 196 print_graph (void)
 197 {
 198   state_number_t i;
 199
 200   /* Output file.  */
 201   fgraph = xfopen (spec_graph_file, "w");
 202
 203   new_graph (&graph);
 204
 205 #if 0
 206   graph.smanhattan_edges = yes;
 207   graph.manhattan_edges = yes;
 208 #endif
 209
 210   graph.display_edge_labels = yes;
 211   graph.layoutalgorithm = normal;
 212
 213   graph.port_sharing = no;
 214   graph.finetuning = yes;
 215   graph.straight_phase = yes;
 216   graph.priority_phase = yes;
 217   graph.splines = yes;
 218
 219   graph.crossing_weight = median;
 220
 221   /* Output graph options. */
 222   open_graph (fgraph);
 223   output_graph (&graph, fgraph);
 224
 225   /* Output nodes and edges. */
 226   new_closure (nritems);
 227   for (i = 0; i < nstates; i++)
 228     print_state (states[i]);
 229   free_closure ();
 230
 231   /* Close graph. */
 232   close_graph (&graph, fgraph);
 233   xfclose (fgraph);
 234 }