/*

  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/>.

*/

// SPDX-License-Identifier: GPL-3.0

#pragma once

#include <libsolidity/analysis/ControlFlowGraph.h>

#include <liblangutil/ErrorReporter.h>

#include <set>

namespace solidity::frontend

{

class ControlFlowAnalyzer

{

public:

  explicit ControlFlowAnalyzer(CFG const& _cfg, langutil::ErrorReporter& _errorReporter):

    m_cfg(_cfg), m_errorReporter(_errorReporter) {}

  bool run();

private:

  void analyze(FunctionDefinition const& _function, ContractDefinition const* _contract, FunctionFlow const& _flow);

  /// Checks for uninitialized variable accesses in the control flow between @param _entry and @param _exit.

  /// @param _entry entry node

  /// @param _exit exit node

  /// @param _emptyBody whether the body of the function is empty (true) or not (false)

  /// @param _contractName name of the most derived contract, should be empty

  ///        if the function is also defined in it

  void checkUninitializedAccess(CFGNode const* _entry, CFGNode const* _exit, bool _emptyBody, std::optional<std::string> _contractName = {});

  /// Checks for unreachable code, i.e. code ending in @param _exit, @param _revert or @param _transactionReturn

  /// that can not be reached from @param _entry.

  void checkUnreachable(CFGNode const* _entry, CFGNode const* _exit, CFGNode const* _revert, CFGNode const* _transactionReturn);

  CFG const& m_cfg;

  langutil::ErrorReporter& m_errorReporter;

  std::set<langutil::SourceLocation> m_unreachableLocationsAlreadyWarnedFor;

  std::set<VariableDeclaration const*> m_unassignedReturnVarsAlreadyWarnedFor;

};

}