solidity/libjulia/backends/evm/AbstractAssembly.h
2017-05-29 15:40:32 +02:00

92 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/>.
*/
/**
* @date 2017
* Abstract assembly interface, subclasses of which are to be used with the generic
* bytecode generator.
*/
#pragma once
#include <libdevcore/CommonData.h>
#include <functional>
namespace dev
{
struct SourceLocation;
namespace solidity
{
enum class Instruction: uint8_t;
namespace assembly
{
struct Instruction;
struct Identifier;
}
}
namespace julia
{
class AbstractAssembly
{
public:
using LabelID = size_t;
virtual ~AbstractAssembly() {}
/// Set a new source location valid starting from the next instruction.
virtual void setSourceLocation(SourceLocation const& _location) = 0;
/// Retrieve the current height of the stack. This does not have to be zero
/// at the beginning.
virtual int stackHeight() const = 0;
/// Append an EVM instruction.
virtual void appendInstruction(solidity::Instruction _instruction) = 0;
/// Append a constant.
virtual void appendConstant(u256 const& _constant) = 0;
/// Append a label.
virtual void appendLabel(LabelID _labelId) = 0;
/// Append a label reference.
virtual void appendLabelReference(LabelID _labelId) = 0;
/// Generate a new unique label.
virtual LabelID newLabelId() = 0;
/// Append a reference to a to-be-linked symobl.
/// Currently, we assume that the value is always a 20 byte number.
virtual void appendLinkerSymbol(std::string const& _name) = 0;
};
enum class IdentifierContext { LValue, RValue };
/// Object that is used to resolve references and generate code for access to identifiers external
/// to inline assembly (not used in standalone assembly mode).
struct ExternalIdentifierAccess
{
using Resolver = std::function<size_t(solidity::assembly::Identifier const&, IdentifierContext)>;
/// Resolve a an external reference given by the identifier in the given context.
/// @returns the size of the value (number of stack slots) or size_t(-1) if not found.
Resolver resolve;
using CodeGenerator = std::function<void(solidity::assembly::Identifier const&, IdentifierContext, julia::AbstractAssembly&)>;
/// Generate code for retrieving the value (rvalue context) or storing the value (lvalue context)
/// of an identifier. The code should be appended to the assembly. In rvalue context, the value is supposed
/// to be put onto the stack, in lvalue context, the value is assumed to be at the top of the stack.
CodeGenerator generateCode;
};
}
}