solidity/libyul/backends/evm/EVMAssembly.h
2020-01-07 15:51:50 +01:00

105 lines
3.7 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/>.
*/
/**
* Assembly interface for EVM and EVM1.5.
*/
#pragma once
#include <libyul/backends/evm/AbstractAssembly.h>
#include <libevmasm/LinkerObject.h>
#include <map>
namespace solidity::langutil
{
struct SourceLocation;
}
namespace solidity::yul
{
class EVMAssembly: public AbstractAssembly
{
public:
explicit EVMAssembly(bool _evm15 = false): m_evm15(_evm15) { }
virtual ~EVMAssembly() = default;
/// Set a new source location valid starting from the next instruction.
void setSourceLocation(langutil::SourceLocation const& _location) override;
/// Retrieve the current height of the stack. This does not have to be zero
/// at the beginning.
int stackHeight() const override { return m_stackHeight; }
void setStackHeight(int height) override { m_stackHeight = height; }
/// Append an EVM instruction.
void appendInstruction(evmasm::Instruction _instruction) override;
/// Append a constant.
void appendConstant(u256 const& _constant) override;
/// Append a label.
void appendLabel(LabelID _labelId) override;
/// Append a label reference.
void appendLabelReference(LabelID _labelId) override;
/// Generate a new unique label.
LabelID newLabelId() override;
/// Returns a label identified by the given name. Creates it if it does not yet exist.
LabelID namedLabel(std::string const& _name) override;
/// Append a reference to a to-be-linked symbol.
/// Currently, we assume that the value is always a 20 byte number.
void appendLinkerSymbol(std::string const& _name) override;
/// Append a jump instruction.
/// @param _stackDiffAfter the stack adjustment after this instruction.
void appendJump(int _stackDiffAfter) override;
/// Append a jump-to-immediate operation.
void appendJumpTo(LabelID _labelId, int _stackDiffAfter) override;
/// Append a jump-to-if-immediate operation.
void appendJumpToIf(LabelID _labelId) override;
/// Start a subroutine.
void appendBeginsub(LabelID _labelId, int _arguments) override;
/// Call a subroutine.
void appendJumpsub(LabelID _labelId, int _arguments, int _returns) override;
/// Return from a subroutine.
void appendReturnsub(int _returns, int _stackDiffAfter) override;
/// Append the assembled size as a constant.
void appendAssemblySize() override;
std::pair<std::shared_ptr<AbstractAssembly>, SubID> createSubAssembly() override;
void appendDataOffset(SubID _sub) override;
void appendDataSize(SubID _sub) override;
SubID appendData(bytes const& _data) override;
/// Resolves references inside the bytecode and returns the linker object.
evmasm::LinkerObject finalize();
private:
void setLabelToCurrentPosition(AbstractAssembly::LabelID _labelId);
void appendLabelReferenceInternal(AbstractAssembly::LabelID _labelId);
void updateReference(size_t pos, size_t size, u256 value);
bool m_evm15 = false; ///< if true, switch to evm1.5 mode
LabelID m_nextLabelId = 0;
int m_stackHeight = 0;
bytes m_bytecode;
std::map<std::string, LabelID> m_namedLabels;
std::map<LabelID, size_t> m_labelPositions;
std::map<size_t, LabelID> m_labelReferences;
std::vector<size_t> m_assemblySizePositions;
};
}