/* This file is part of cpp-ethereum. cpp-ethereum 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. cpp-ethereum 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 cpp-ethereum. If not, see <http://www.gnu.org/licenses/>. */ /** @file PathGasMeter.cpp * @author Christian <c@ethdev.com> * @date 2015 */ #pragma once #include <set> #include <vector> #include <memory> #include <libevmasm/GasMeter.h> namespace dev { namespace eth { class KnownState; struct GasPath { size_t index = 0; std::shared_ptr<KnownState> state; u256 largestMemoryAccess; GasMeter::GasConsumption gas; std::set<size_t> visitedJumpdests; }; /** * Computes an upper bound on the gas usage of a computation starting at a certain position in * a list of AssemblyItems in a given state until the computation stops. * Can be used to estimate the gas usage of functions on any given input. */ class PathGasMeter { public: PathGasMeter(AssemblyItems const& _items); GasMeter::GasConsumption estimateMax(size_t _startIndex, std::shared_ptr<KnownState> const& _state); private: GasMeter::GasConsumption handleQueueItem(); std::vector<std::unique_ptr<GasPath>> m_queue; std::map<u256, size_t> m_tagPositions; AssemblyItems const& m_items; }; } }