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 "gram.h"
  25 #include "LR0.h"
  26 #include "lalr.h"
  27 #include "conflicts.h"
  28 #include "complain.h"
  29 #include "getargs.h"
  30 #include "state.h"
  31 #include "reader.h"
  32 #include "closure.h"
  33 #include "obstack.h"
  34 #include "print_graph.h"
  35 #include "vcg.h"
  36
  37 static graph_t graph;
  38 static FILE *fgraph = NULL;
  39
  40 static inline const char *
  41 escape (const char *s)
  42 {
  43   return quotearg_n_style (1, escape_quoting_style, s);
  44 }
  45
  46
  47 /* This part will construct the label of nodes. */
  48 static void
  49 print_core (state_t *state, struct obstack *node_obstack)
  50 {
  51   int i;
  52   short *sitems = state->items;
  53   int snitems   = state->nitems;
  54
  55   /* Output all the items of a state, not only its kernel.  */
  56   closure (sitems, snitems);
  57   sitems = itemset;
  58   snitems = nitemset;
  59
  60   obstack_fgrow1 (node_obstack, "state %2d\n", state->number);
  61   for (i = 0; i < snitems; i++)
  62     {
  63       short *sp;
  64       short *sp1;
  65       int rule;
  66
  67       sp1 = sp = ritem + sitems[i];
  68
  69       while (*sp > 0)
  70         sp++;
  71
  72       rule = -(*sp);
  73
  74       if (i)
  75         obstack_1grow (node_obstack, '\n');
  76       obstack_fgrow1 (node_obstack, " %s -> ",
  77                       escape (tags[rule_table[rule].lhs]));
  78
  79       for (sp = ritem + rule_table[rule].rhs; sp < sp1; sp++)
  80         obstack_fgrow1 (node_obstack, "%s ", escape (tags[*sp]));
  81
  82       obstack_1grow (node_obstack, '.');
  83
  84       for (/* Nothing */; *sp > 0; ++sp)
  85         obstack_fgrow1 (node_obstack, " %s", escape (tags[*sp]));
  86     }
  87 }
  88
  89
  90 /*---------------------------------------------------------------.
  91 | Output in graph_obstack edges specifications in incidence with |
  92 | current node.                                                  |
  93 `---------------------------------------------------------------*/
  94
  95 static void
  96 print_actions (state_t *state, const char *node_name)
  97 {
  98   int i;
  99
 100   shifts   *shiftp = state->shifts;
 101   reductions *redp = state->reductions;
 102
 103   static char buff[10];
 104   edge_t edge;
 105
 106   if (!shiftp->nshifts && !redp)
 107     return;
 108
 109   for (i = 0; i < shiftp->nshifts; i++)
 110     if (!SHIFT_IS_DISABLED (shiftp, i))
 111       {
 112         int state1 = shiftp->shifts[i];
 113         int symbol = state_table[state1]->accessing_symbol;
 114
 115         new_edge (&edge);
 116
 117         if (state->number > state1)
 118           edge.type = back_edge;
 119         open_edge (&edge, fgraph);
 120         /* The edge source is the current node.  */
 121         edge.sourcename = node_name;
 122         sprintf (buff, "%d", state1);
 123         edge.targetname = buff;
 124         /* Shifts are blue, gotos are green, and error is red. */
 125         if (SHIFT_IS_ERROR (shiftp, i))
 126           edge.color = red;
 127         else
 128           edge.color = SHIFT_IS_SHIFT(shiftp, i) ? blue : green;
 129         edge.label = escape (tags[symbol]);
 130         output_edge (&edge, fgraph);
 131         close_edge (fgraph);
 132       }
 133 }
 134
 135
 136 /*-------------------------------------------------------------.
 137 | Output in FGRAPH the current node specifications and exiting |
 138 | edges.                                                       |
 139 `-------------------------------------------------------------*/
 140
 141 static void
 142 print_state (state_t *state)
 143 {
 144   static char name[10];
 145   struct obstack node_obstack;
 146   node_t node;
 147
 148   /* The labels of the nodes are their the items.  */
 149   obstack_init (&node_obstack);
 150   new_node (&node);
 151   sprintf (name, "%d", state->number);
 152   node.title = name;
 153   print_core (state, &node_obstack);
 154   obstack_1grow (&node_obstack, '\0');
 155   node.label = obstack_finish (&node_obstack);
 156
 157   open_node (fgraph);
 158   output_node (&node, fgraph);
 159   close_node (fgraph);
 160
 161   /* Output the edges.  */
 162   print_actions (state, name);
 163
 164   obstack_free (&node_obstack, 0);
 165 }
 166 \f
 167
 168 void
 169 print_graph (void)
 170 {
 171   int i;
 172
 173   /* Output file.  */
 174   fgraph = xfopen (spec_graph_file, "w");
 175
 176   new_graph (&graph);
 177
 178 #if 0
 179   graph.smanhattan_edges = yes;
 180   graph.manhattan_edges = yes;
 181 #endif
 182
 183   graph.display_edge_labels = yes;
 184   graph.layoutalgorithm = normal;
 185
 186   graph.port_sharing = no;
 187   graph.finetuning = yes;
 188   graph.straight_phase = yes;
 189   graph.priority_phase = yes;
 190   graph.splines = yes;
 191
 192   graph.crossing_weight = median;
 193
 194   /* Output graph options. */
 195   open_graph (fgraph);
 196   output_graph (&graph, fgraph);
 197
 198   /* Output nodes and edges. */
 199   new_closure (nitems);
 200   for (i = 0; i < nstates; i++)
 201     print_state (state_table[i]);
 202   free_closure ();
 203
 204   /* Close graph. */
 205   close_graph (&graph, fgraph);
 206   xfclose (fgraph);
 207 }