Added output in DOT format for class hierarchy. (#642)

Added output in DOT format.

Author: marek-trtik

src/goto-programs/class_hierarchy.cpp

@@ -135,3 +135,30 @@ void class_hierarchyt::output(std::ostream &out) const
           << ch << '\n';
   }
 }
+
+/*******************************************************************\
+
+Function: output_dot
+
+  Inputs:
+
+ Outputs:
+
+ Purpose:
+
+\*******************************************************************/
+
+std::ostream &output_dot(std::ostream &ostr, const class_hierarchyt &hierarchy)
+{
+  ostr << "digraph call_graph {\n"
+       << "  rankdir=BT;\n"
+       << "  node [fontsize=12 shape=box];\n";
+  for(const auto &c : hierarchy.class_map)
+    for(const auto &ch : c.second.parents)
+      ostr << "  \"" << c.first << "\" -> "
+           << "\"" << ch << "\" "
+           << " [arrowhead=\"vee\"];"
+           << "\n";
+  ostr << "}\n";
+  return ostr;
+}

src/goto-programs/class_hierarchy.h

@@ -55,4 +55,6 @@ class class_hierarchyt
   void get_parents_trans_rec(const irep_idt &, idst &) const;
 };
 
+std::ostream &output_dot(std::ostream &ostr, const class_hierarchyt &hierarchy);
+
 #endif // CPROVER_GOTO_PROGRAMS_CLASS_HIERARCHY_H