Line data    Source code

       1             : // Author(s): Luc Engelen
       2             : // Copyright: see the accompanying file COPYING or copy at
       3             : // https://github.com/mCRL2org/mCRL2/blob/master/COPYING
       4             : //
       5             : // Distributed under the Boost Software License, Version 1.0.
       6             : // (See accompanying file LICENSE_1_0.txt or copy at
       7             : // http://www.boost.org/LICENSE_1_0.txt)
       8             : //
       9             : /// \file mcrl2/utilities/bdd_info.h
      10             : /// \brief Interface to class BDD_Info
      11             : 
      12             : #ifndef MCRL2_DATA_DETAIL_PROVER_BDD_INFO_H
      13             : #define MCRL2_DATA_DETAIL_PROVER_BDD_INFO_H
      14             : 
      15             : #include "mcrl2/data/bool.h"
      16             : 
      17             : namespace mcrl2
      18             : {
      19             : namespace data
      20             : {
      21             : namespace detail
      22             : {
      23             : 
      24             : /// \brief The class BDD_Info provides information about the structure of binary decision diagrams.
      25             : class BDD_Info
      26             : {
      27             :   protected:
      28           0 :     static const mcrl2::data::data_expression& argument(const mcrl2::data::data_expression& x, std::size_t n)
      29             :     {
      30           0 :       const mcrl2::data::application& a = atermpp::down_cast<mcrl2::data::application>(x);
      31           0 :       return a[n]; 
      32             :       // mcrl2::data::application::const_iterator i = a.begin();
      33             :       // std::advance(i, n);
      34             :       // return *i;
      35             :     }
      36             : 
      37             :   public:
      38             : 
      39             :     /// \brief Method that returns the guard of a BDD.
      40             :     /// \param[in] a_bdd A binary decision diagram.
      41             :     /// \return The guard at the root of the BDD.
      42           0 :     static inline const mcrl2::data::data_expression& get_guard(const mcrl2::data::data_expression& a_bdd)
      43             :     {
      44           0 :       return argument(a_bdd,0);
      45             :     }
      46             : 
      47             :     /// \brief Method that returns the true-branch of a BDD.
      48             :     /// \param[in] a_bdd A binary decision diagram.
      49             :     /// \return The true-branch of the BDD.
      50           0 :     static inline const mcrl2::data::data_expression& get_true_branch(const mcrl2::data::data_expression&  a_bdd)
      51             :     {
      52           0 :       return argument(a_bdd,1);
      53             :     }
      54             : 
      55             :     /// \brief Method that returns the false-branch of a BDD.
      56             :     /// \param[in] a_bdd A binary decision diagram.
      57             :     /// \return The false-branch of the BDD.
      58           0 :     static inline const mcrl2::data::data_expression& get_false_branch(const mcrl2::data::data_expression& a_bdd)
      59             :     {
      60           0 :       return argument(a_bdd,2);
      61             :     }
      62             : 
      63             :     /// \brief Method that indicates whether or not a BDD equals true.
      64             :     /// \param[in] a_bdd A binary decision diagram.
      65             :     /// \return True, if the BDD equals true.
      66             :     ///         False, if the BDD does not equal true.
      67          81 :     static inline bool is_true(const data_expression& a_bdd)
      68             :     {
      69          81 :       return mcrl2::data::sort_bool::is_true_function_symbol(a_bdd);
      70             :     }
      71             : 
      72             :     /// \brief Method that indicates whether or not a BDD equals false.
      73             :     /// \param[in] a_bdd A binary decision diagram.
      74             :     /// \return True, if the BDD equals false.
      75             :     ///         False, if the BDD does not equal true.
      76          22 :     static inline bool is_false(const data_expression& a_bdd)
      77             :     {
      78          22 :       return mcrl2::data::sort_bool::is_false_function_symbol(a_bdd);
      79             :     }
      80             : 
      81             :     /// \brief Method that indicates wether or not the root of a BDD is a guard node.
      82             :     /// \param[in] a_bdd A binary decision diagram.
      83             :     /// \return True, if the root of the BDD is a guard node.
      84             :     ///         False, if the BDD equals true or if the BDD equals false.
      85           0 :     static inline bool is_if_then_else(const data_expression& a_bdd)
      86             :     {
      87           0 :       return mcrl2::data::is_if_application(a_bdd);
      88             :     }
      89             : };
      90             : 
      91             : } // namespace detail
      92             : } // namespace data
      93             : } // namespace mcrl2
      94             : 
      95             : #endif