solidity/test/tools/yulInterpreter/EVMInstructionInterpreter.h
2019-02-25 11:57:48 +01:00

90 lines
2.9 KiB
C++

/*
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/>.
*/
/**
* Yul interpreter module that evaluates EVM instructions.
*/
#pragma once
#include <libyul/AsmDataForward.h>
#include <libdevcore/CommonData.h>
#include <vector>
namespace dev
{
namespace solidity
{
enum class Instruction: uint8_t;
}
}
namespace yul
{
namespace test
{
struct InterpreterState;
/**
* Interprets EVM instructions based on the current state and logs instructions with
* side-effects.
*
* Since this is mainly meant to be used for testing, it is focused on a single
* contract only, does not do any gas counting and differs from the correct
* implementation in the following ways:
*
* - If memory access to a "large" memory position is performed, a deterministic
* value is returned. Data that is stored in a "large" memory position is not
* retained.
* - The blockhash instruction returns a fixed value if the argument is in range.
* - Extcodesize returns a deterministic value depending on the address.
* - Extcodecopy copies a deterministic value depending on the address.
* - And many other things
* - TODO
*
*/
class EVMInstructionInterpreter
{
public:
explicit EVMInstructionInterpreter(InterpreterState& _state):
m_state(_state)
{}
dev::u256 eval(dev::solidity::Instruction _instruction, std::vector<dev::u256> const& _arguments);
private:
/// Record a memory read in the trace. Also updaes m_state.msize
/// @returns true if m_state.memory can be used at that offset.
bool logMemoryRead(dev::u256 const& _offset, dev::u256 const& _size = 32);
/// Record a memory write in the trace. Also updaes m_state.msize
/// @returns true if m_state.memory can be used at that offset.
bool logMemoryWrite(dev::u256 const& _offset, dev::u256 const& _size = 32, dev::bytes const& _data = {});
bool logMemory(bool _write, dev::u256 const& _offset, dev::u256 const& _size = 32, dev::bytes const& _data = {});
void logTrace(dev::solidity::Instruction _instruction, std::vector<dev::u256> const& _arguments = {}, dev::bytes const& _data = {});
/// Appends a log to the trace representing an instruction or similar operation by string,
/// with arguments and auxiliary data (if nonempty).
void logTrace(std::string const& _pseudoInstruction, std::vector<dev::u256> const& _arguments = {}, dev::bytes const& _data = {});
InterpreterState& m_state;
};
}
}