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 = item_number_as_rule_number (*sp);
  74
  75       if (i)
  76         obstack_1grow (oout, '\n');
  77       obstack_fgrow1 (oout, " %s -> ",
  78                       rules[rule].lhs->tag);
  79
  80       for (sp = rules[rule].rhs; sp < sp1; sp++)
  81         obstack_fgrow1 (oout, "%s ", symbols[*sp]->tag);
  82
  83       obstack_1grow (oout, '.');
  84
  85       for (/* Nothing */; *sp >= 0; ++sp)
  86         obstack_fgrow1 (oout, " %s", symbols[*sp]->tag);
  87
  88       /* Experimental feature: display the lookaheads. */
  89       if ((report_flag & report_lookaheads)
  90           && state->nlookaheads)
  91         {
  92           int j, k;
  93           bitset_iterator biter;
  94           int nlookaheads = 0;
  95
  96           /* Look for lookaheads corresponding to this rule. */
  97           for (j = 0; j < state->nlookaheads; ++j)
  98             BITSET_FOR_EACH (biter, state->lookaheads[j], k, 0)
  99               if (state->lookaheads_rule[j]->number == rule)
 100                 nlookaheads++;
 101
 102           if (nlookaheads)
 103             {
 104               obstack_sgrow (oout, "  [");
 105               for (j = 0; j < state->nlookaheads; ++j)
 106                 BITSET_FOR_EACH (biter, state->lookaheads[j], k, 0)
 107                   if (state->lookaheads_rule[j]->number == rule)
 108                     obstack_fgrow2 (oout, "%s%s",
 109                                     symbols[k]->tag,
 110                                     --nlookaheads ? ", " : "");
 111               obstack_sgrow (oout, "]");
 112             }
 113         }
 114     }
 115 }
 116
 117
 118 /*---------------------------------------------------------------.
 119 | Output in graph_obstack edges specifications in incidence with |
 120 | current node.                                                  |
 121 `---------------------------------------------------------------*/
 122
 123 static void
 124 print_actions (state_t *state, const char *node_name)
 125 {
 126   int i;
 127
 128   transitions_t     *transitions = state->transitions;
 129   reductions_t *redp = state->reductions;
 130
 131   static char buff[10];
 132   edge_t edge;
 133
 134   if (!transitions->num && !redp)
 135     return;
 136
 137   for (i = 0; i < transitions->num; i++)
 138     if (!TRANSITION_IS_DISABLED (transitions, i))
 139       {
 140         state_t *state1 = transitions->states[i];
 141         symbol_number_t symbol = state1->accessing_symbol;
 142
 143         new_edge (&edge);
 144
 145         if (state->number > state1->number)
 146           edge.type = back_edge;
 147         open_edge (&edge, fgraph);
 148         /* The edge source is the current node.  */
 149         edge.sourcename = node_name;
 150         sprintf (buff, "%d", state1->number);
 151         edge.targetname = buff;
 152         /* Shifts are blue, gotos are green, and error is red. */
 153         if (TRANSITION_IS_ERROR (transitions, i))
 154           edge.color = red;
 155         else
 156           edge.color = TRANSITION_IS_SHIFT(transitions, i) ? blue : green;
 157         edge.label = symbols[symbol]->tag;
 158         output_edge (&edge, fgraph);
 159         close_edge (fgraph);
 160       }
 161 }
 162
 163
 164 /*-------------------------------------------------------------.
 165 | Output in FGRAPH the current node specifications and exiting |
 166 | edges.                                                       |
 167 `-------------------------------------------------------------*/
 168
 169 static void
 170 print_state (state_t *state)
 171 {
 172   static char name[10];
 173   struct obstack node_obstack;
 174   node_t node;
 175
 176   /* The labels of the nodes are their the items.  */
 177   obstack_init (&node_obstack);
 178   new_node (&node);
 179   sprintf (name, "%d", state->number);
 180   node.title = name;
 181   print_core (&node_obstack, state);
 182   obstack_1grow (&node_obstack, '\0');
 183   node.label = obstack_finish (&node_obstack);
 184
 185   open_node (fgraph);
 186   output_node (&node, fgraph);
 187   close_node (fgraph);
 188
 189   /* Output the edges.  */
 190   print_actions (state, name);
 191
 192   obstack_free (&node_obstack, 0);
 193 }
 194 \f
 195
 196 void
 197 print_graph (void)
 198 {
 199   state_number_t i;
 200
 201   /* Output file.  */
 202   fgraph = xfopen (spec_graph_file, "w");
 203
 204   new_graph (&graph);
 205
 206 #if 0
 207   graph.smanhattan_edges = yes;
 208   graph.manhattan_edges = yes;
 209 #endif
 210
 211   graph.display_edge_labels = yes;
 212   graph.layoutalgorithm = normal;
 213
 214   graph.port_sharing = no;
 215   graph.finetuning = yes;
 216   graph.straight_phase = yes;
 217   graph.priority_phase = yes;
 218   graph.splines = yes;
 219
 220   graph.crossing_weight = median;
 221
 222   /* Output graph options. */
 223   open_graph (fgraph);
 224   output_graph (&graph, fgraph);
 225
 226   /* Output nodes and edges. */
 227   new_closure (nritems);
 228   for (i = 0; i < nstates; i++)
 229     print_state (states[i]);
 230   free_closure ();
 231
 232   /* Close graph. */
 233   close_graph (&graph, fgraph);
 234   xfclose (fgraph);
 235 }