path: root/libsolidity/formal/SymbolicVariable.h

/*
    This file is part of solidity.

    solidity is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    solidity is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with solidity.  If not, see <http://www.gnu.org/licenses/>.
*/

#pragma once

#include <libsolidity/formal/SolverInterface.h>

#include <libsolidity/ast/AST.h>

#include <memory>

namespace dev
{
namespace solidity
{

class Declaration;

/**
 * This class represents the symbolic version of a program variable.
 */
class SymbolicVariable
{
public:
    SymbolicVariable(
        Declaration const& _decl,
        smt::SolverInterface& _interface
    );

    smt::Expression operator()(int _seq) const
    {
        return valueAtSequence(_seq);
    }

    std::string uniqueSymbol(int _seq) const;

    /// Sets the var to the default value of its type.
    virtual void setZeroValue(int _seq) = 0;
    /// The unknown value is the full range of valid values,
    /// and that's sub-type dependent.
    virtual void setUnknownValue(int _seq) = 0;

protected:
    virtual smt::Expression valueAtSequence(int _seq) const = 0;

    Declaration const& m_declaration;
    smt::SolverInterface& m_interface;
};

}
}