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 (trace_flag)
  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       int rule;
  67
  68       sp1 = sp = ritem + sitems[i];
  69
  70       while (*sp >= 0)
  71         sp++;
  72
  73       rule = -(*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 (trace_flag && state->nlookaheads)
  90         {
  91           int j, k;
  92           int nlookaheads = 0;
  93           /* Look for lookaheads corresponding to this rule. */
  94           for (j = 0; j < state->nlookaheads; ++j)
  95             for (k = 0; k < ntokens; ++k)
  96               if (bitset_test (state->lookaheads[j], k)
  97                   && state->lookaheads_rule[j]->number == rule)
  98                 nlookaheads++;
  99           if (nlookaheads)
 100             {
 101               obstack_sgrow (oout, "  [");
 102               for (j = 0; j < state->nlookaheads; ++j)
 103                 for (k = 0; k < ntokens; ++k)
 104                   if (bitset_test (state->lookaheads[j], k)
 105                       && state->lookaheads_rule[j]->number == rule)
 106                     obstack_fgrow2 (oout, "%s%s",
 107                                     symbol_tag_get (symbols[k]),
 108                                     --nlookaheads ? ", " : "");
 109               obstack_sgrow (oout, "]");
 110             }
 111         }
 112     }
 113 }
 114
 115
 116 /*---------------------------------------------------------------.
 117 | Output in graph_obstack edges specifications in incidence with |
 118 | current node.                                                  |
 119 `---------------------------------------------------------------*/
 120
 121 static void
 122 print_actions (state_t *state, const char *node_name)
 123 {
 124   int i;
 125
 126   shifts   *shiftp = state->shifts;
 127   reductions *redp = state->reductions;
 128
 129   static char buff[10];
 130   edge_t edge;
 131
 132   if (!shiftp->nshifts && !redp)
 133     return;
 134
 135   for (i = 0; i < shiftp->nshifts; i++)
 136     if (!SHIFT_IS_DISABLED (shiftp, i))
 137       {
 138         state_number_t state1 = shiftp->shifts[i];
 139         symbol_number_t symbol = states[state1]->accessing_symbol;
 140
 141         new_edge (&edge);
 142
 143         if (state->number > state1)
 144           edge.type = back_edge;
 145         open_edge (&edge, fgraph);
 146         /* The edge source is the current node.  */
 147         edge.sourcename = node_name;
 148         sprintf (buff, "%d", state1);
 149         edge.targetname = buff;
 150         /* Shifts are blue, gotos are green, and error is red. */
 151         if (SHIFT_IS_ERROR (shiftp, i))
 152           edge.color = red;
 153         else
 154           edge.color = SHIFT_IS_SHIFT(shiftp, i) ? blue : green;
 155         edge.label = symbol_tag_get (symbols[symbol]);
 156         output_edge (&edge, fgraph);
 157         close_edge (fgraph);
 158       }
 159 }
 160
 161
 162 /*-------------------------------------------------------------.
 163 | Output in FGRAPH the current node specifications and exiting |
 164 | edges.                                                       |
 165 `-------------------------------------------------------------*/
 166
 167 static void
 168 print_state (state_t *state)
 169 {
 170   static char name[10];
 171   struct obstack node_obstack;
 172   node_t node;
 173
 174   /* The labels of the nodes are their the items.  */
 175   obstack_init (&node_obstack);
 176   new_node (&node);
 177   sprintf (name, "%d", state->number);
 178   node.title = name;
 179   print_core (&node_obstack, state);
 180   obstack_1grow (&node_obstack, '\0');
 181   node.label = obstack_finish (&node_obstack);
 182
 183   open_node (fgraph);
 184   output_node (&node, fgraph);
 185   close_node (fgraph);
 186
 187   /* Output the edges.  */
 188   print_actions (state, name);
 189
 190   obstack_free (&node_obstack, 0);
 191 }
 192 \f
 193
 194 void
 195 print_graph (void)
 196 {
 197   state_number_t i;
 198
 199   /* Output file.  */
 200   fgraph = xfopen (spec_graph_file, "w");
 201
 202   new_graph (&graph);
 203
 204 #if 0
 205   graph.smanhattan_edges = yes;
 206   graph.manhattan_edges = yes;
 207 #endif
 208
 209   graph.display_edge_labels = yes;
 210   graph.layoutalgorithm = normal;
 211
 212   graph.port_sharing = no;
 213   graph.finetuning = yes;
 214   graph.straight_phase = yes;
 215   graph.priority_phase = yes;
 216   graph.splines = yes;
 217
 218   graph.crossing_weight = median;
 219
 220   /* Output graph options. */
 221   open_graph (fgraph);
 222   output_graph (&graph, fgraph);
 223
 224   /* Output nodes and edges. */
 225   new_closure (nritems);
 226   for (i = 0; i < nstates; i++)
 227     print_state (states[i]);
 228   free_closure ();
 229
 230   /* Close graph. */
 231   close_graph (&graph, fgraph);
 232   xfclose (fgraph);
 233 }