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 static inline const char *
  42 escape (const char *s)
  43 {
  44   return quotearg_n_style (1, escape_quoting_style, s);
  45 }
  46
  47
  48 /* This part will construct the label of nodes. */
  49 static void
  50 print_core (struct obstack *oout, state_t *state)
  51 {
  52   int i;
  53   item_number_t *sitems = state->items;
  54   int snritems   = state->nitems;
  55
  56   /* Output all the items of a state, not only its kernel.  */
  57   if (trace_flag)
  58     {
  59       closure (sitems, snritems);
  60       sitems = itemset;
  61       snritems = nritemset;
  62     }
  63
  64   obstack_fgrow1 (oout, "state %2d\n", state->number);
  65   for (i = 0; i < snritems; i++)
  66     {
  67       item_number_t *sp;
  68       item_number_t *sp1;
  69       int rule;
  70
  71       sp1 = sp = ritem + sitems[i];
  72
  73       while (*sp >= 0)
  74         sp++;
  75
  76       rule = -(*sp);
  77
  78       if (i)
  79         obstack_1grow (oout, '\n');
  80       obstack_fgrow1 (oout, " %s -> ",
  81                       escape (rules[rule].lhs->tag));
  82
  83       for (sp = rules[rule].rhs; sp < sp1; sp++)
  84         obstack_fgrow1 (oout, "%s ", escape (symbols[*sp]->tag));
  85
  86       obstack_1grow (oout, '.');
  87
  88       for (/* Nothing */; *sp >= 0; ++sp)
  89         obstack_fgrow1 (oout, " %s", escape (symbols[*sp]->tag));
  90
  91       /* Experimental feature: display the lookaheads. */
  92       if (trace_flag && state->nlookaheads)
  93         {
  94           int j, k;
  95           int nlookaheads = 0;
  96           /* Look for lookaheads corresponding to this rule. */
  97           for (j = 0; j < state->nlookaheads; ++j)
  98             for (k = 0; k < ntokens; ++k)
  99               if (bitset_test (LA[state->lookaheadsp + j], k)
 100                   && LArule[state->lookaheadsp + j]->number == rule)
 101                 nlookaheads++;
 102           if (nlookaheads)
 103             {
 104               obstack_sgrow (oout, "  [");
 105               for (j = 0; j < state->nlookaheads; ++j)
 106                 for (k = 0; k < ntokens; ++k)
 107                   if (bitset_test (LA[state->lookaheadsp + j], k)
 108                       && LArule[state->lookaheadsp + j]->number == rule)
 109                     obstack_fgrow2 (oout, "%s%s",
 110                                     quotearg_style (escape_quoting_style,
 111                                                     symbols[k]->tag),
 112                                     --nlookaheads ? ", " : "");
 113               obstack_sgrow (oout, "]");
 114             }
 115         }
 116     }
 117 }
 118
 119
 120 /*---------------------------------------------------------------.
 121 | Output in graph_obstack edges specifications in incidence with |
 122 | current node.                                                  |
 123 `---------------------------------------------------------------*/
 124
 125 static void
 126 print_actions (state_t *state, const char *node_name)
 127 {
 128   int i;
 129
 130   shifts   *shiftp = state->shifts;
 131   reductions *redp = state->reductions;
 132
 133   static char buff[10];
 134   edge_t edge;
 135
 136   if (!shiftp->nshifts && !redp)
 137     return;
 138
 139   for (i = 0; i < shiftp->nshifts; i++)
 140     if (!SHIFT_IS_DISABLED (shiftp, i))
 141       {
 142         int state1 = shiftp->shifts[i];
 143         symbol_number_t symbol = states[state1]->accessing_symbol;
 144
 145         new_edge (&edge);
 146
 147         if (state->number > state1)
 148           edge.type = back_edge;
 149         open_edge (&edge, fgraph);
 150         /* The edge source is the current node.  */
 151         edge.sourcename = node_name;
 152         sprintf (buff, "%d", state1);
 153         edge.targetname = buff;
 154         /* Shifts are blue, gotos are green, and error is red. */
 155         if (SHIFT_IS_ERROR (shiftp, i))
 156           edge.color = red;
 157         else
 158           edge.color = SHIFT_IS_SHIFT(shiftp, i) ? blue : green;
 159         edge.label = escape (symbols[symbol]->tag);
 160         output_edge (&edge, fgraph);
 161         close_edge (fgraph);
 162       }
 163 }
 164
 165
 166 /*-------------------------------------------------------------.
 167 | Output in FGRAPH the current node specifications and exiting |
 168 | edges.                                                       |
 169 `-------------------------------------------------------------*/
 170
 171 static void
 172 print_state (state_t *state)
 173 {
 174   static char name[10];
 175   struct obstack node_obstack;
 176   node_t node;
 177
 178   /* The labels of the nodes are their the items.  */
 179   obstack_init (&node_obstack);
 180   new_node (&node);
 181   sprintf (name, "%d", state->number);
 182   node.title = name;
 183   print_core (&node_obstack, state);
 184   obstack_1grow (&node_obstack, '\0');
 185   node.label = obstack_finish (&node_obstack);
 186
 187   open_node (fgraph);
 188   output_node (&node, fgraph);
 189   close_node (fgraph);
 190
 191   /* Output the edges.  */
 192   print_actions (state, name);
 193
 194   obstack_free (&node_obstack, 0);
 195 }
 196 \f
 197
 198 void
 199 print_graph (void)
 200 {
 201   size_t i;
 202
 203   /* Output file.  */
 204   fgraph = xfopen (spec_graph_file, "w");
 205
 206   new_graph (&graph);
 207
 208 #if 0
 209   graph.smanhattan_edges = yes;
 210   graph.manhattan_edges = yes;
 211 #endif
 212
 213   graph.display_edge_labels = yes;
 214   graph.layoutalgorithm = normal;
 215
 216   graph.port_sharing = no;
 217   graph.finetuning = yes;
 218   graph.straight_phase = yes;
 219   graph.priority_phase = yes;
 220   graph.splines = yes;
 221
 222   graph.crossing_weight = median;
 223
 224   /* Output graph options. */
 225   open_graph (fgraph);
 226   output_graph (&graph, fgraph);
 227
 228   /* Output nodes and edges. */
 229   new_closure (nritems);
 230   for (i = 0; i < nstates; i++)
 231     print_state (states[i]);
 232   free_closure ();
 233
 234   /* Close graph. */
 235   close_graph (&graph, fgraph);
 236   xfclose (fgraph);
 237 }