/*
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/>.
*/
/**
* @author Christian <c@ethdev.com>
* @date 2014
* Utilities for the solidity compiler.
*/
#pragma once
#include <ostream>
#include <stack>
#include <utility>
#include <libevmcore/Instruction.h>
#include <libevmasm/Assembly.h>
#include <libsolidity/ASTForward.h>
#include <libsolidity/Types.h>
#include <libdevcore/Common.h>
namespace dev {
namespace solidity {
/**
* Context to be shared by all units that compile the same contract.
* It stores the generated bytecode and the position of identifiers in memory and on the stack.
*/
class CompilerContext
{
public:
void addMagicGlobal(MagicVariableDeclaration const& _declaration);
void addStateVariable(VariableDeclaration const& _declaration, u256 const& _storageOffset, unsigned _byteOffset);
void addVariable(VariableDeclaration const& _declaration, unsigned _offsetToCurrent = 0);
void removeVariable(VariableDeclaration const& _declaration);
void setCompiledContracts(std::map<ContractDefinition const*, bytes const*> const& _contracts) { m_compiledContracts = _contracts; }
bytes const& getCompiledContract(ContractDefinition const& _contract) const;
void setStackOffset(int _offset) { m_asm.setDeposit(_offset); }
void adjustStackOffset(int _adjustment) { m_asm.adjustDeposit(_adjustment); }
unsigned getStackHeight() const { solAssert(m_asm.deposit() >= 0, ""); return unsigned(m_asm.deposit()); }
bool isMagicGlobal(Declaration const* _declaration) const { return m_magicGlobals.count(_declaration) != 0; }
bool isLocalVariable(Declaration const* _declaration) const;
bool isStateVariable(Declaration const* _declaration) const { return m_stateVariables.count(_declaration) != 0; }
/// @returns the entry label of the given function and creates it if it does not exist yet.
eth::AssemblyItem getFunctionEntryLabel(Declaration const& _declaration);
/// @returns the entry label of the given function. Might return an AssemblyItem of type
/// UndefinedItem if it does not exist yet.
eth::AssemblyItem getFunctionEntryLabelIfExists(Declaration const& _declaration) const;
void setInheritanceHierarchy(std::vector<ContractDefinition const*> const& _hierarchy) { m_inheritanceHierarchy = _hierarchy; }
/// @returns the entry label of the given function and takes overrides into account.
eth::AssemblyItem getVirtualFunctionEntryLabel(FunctionDefinition const& _function);
/// @returns the entry label of a function that overrides the given declaration from the most derived class just
/// above _base in the current inheritance hierarchy.
eth::AssemblyItem getSuperFunctionEntryLabel(FunctionDefinition const& _function, ContractDefinition const& _base);
FunctionDefinition const* getNextConstructor(ContractDefinition const& _contract) const;
/// @returns the set of functions for which we still need to generate code
std::set<Declaration const*> getFunctionsWithoutCode();
/// Resets function specific members, inserts the function entry label and marks the function
/// as "having code".
void startFunction(Declaration const& _function);
ModifierDefinition const& getFunctionModifier(std::string const& _name) const;
/// Returns the distance of the given local variable from the bottom of the stack (of the current function).
unsigned getBaseStackOffsetOfVariable(Declaration const& _declaration) const;
/// If supplied by a value returned by @ref getBaseStackOffsetOfVariable(variable), returns
/// the distance of that variable from the current top of the stack.
unsigned baseToCurrentStackOffset(unsigned _baseOffset) const;
/// Converts an offset relative to the current stack height to a value that can be used later
/// with baseToCurrentStackOffset to point to the same stack element.
unsigned currentToBaseStackOffset(unsigned _offset) const;
/// @returns pair of slot and byte offset of the value inside this slot.
std::pair<u256, unsigned> getStorageLocationOfVariable(Declaration const& _declaration) const;
/// Appends a JUMPI instruction to a new tag and @returns the tag
eth::AssemblyItem appendConditionalJump() { return m_asm.appendJumpI().tag(); }
/// Appends a JUMPI instruction to @a _tag
CompilerContext& appendConditionalJumpTo(eth::AssemblyItem const& _tag) { m_asm.appendJumpI(_tag); return *this; }
/// Appends a JUMP to a new tag and @returns the tag
eth::AssemblyItem appendJumpToNew() { return m_asm.appendJump().tag(); }
/// Appends a JUMP to a tag already on the stack
CompilerContext& appendJump(eth::AssemblyItem::JumpType _jumpType = eth::AssemblyItem::JumpType::Ordinary);
/// Returns an "ErrorTag"
eth::AssemblyItem errorTag() { return m_asm.errorTag(); }
/// Appends a JUMP to a specific tag
CompilerContext& appendJumpTo(eth::AssemblyItem const& _tag) { m_asm.appendJump(_tag); return *this; }
/// Appends pushing of a new tag and @returns the new tag.
eth::AssemblyItem pushNewTag() { return m_asm.append(m_asm.newPushTag()).tag(); }
/// @returns a new tag without pushing any opcodes or data
eth::AssemblyItem newTag() { return m_asm.newTag(); }
/// Adds a subroutine to the code (in the data section) and pushes its size (via a tag)
/// on the stack. @returns the assembly item corresponding to the pushed subroutine, i.e. its offset.
eth::AssemblyItem addSubroutine(eth::Assembly const& _assembly) { return m_asm.appendSubSize(_assembly); }
/// Pushes the size of the final program
void appendProgramSize() { return m_asm.appendProgramSize(); }
/// Adds data to the data section, pushes a reference to the stack
eth::AssemblyItem appendData(bytes const& _data) { return m_asm.append(_data); }
/// Resets the stack of visited nodes with a new stack having only @c _node
void resetVisitedNodes(ASTNode const* _node);
/// Pops the stack of visited nodes
void popVisitedNodes() { m_visitedNodes.pop(); updateSourceLocation(); }
/// Pushes an ASTNode to the stack of visited nodes
void pushVisitedNodes(ASTNode const* _node) { m_visitedNodes.push(_node); updateSourceLocation(); }
/// Append elements to the current instruction list and adjust @a m_stackOffset.
CompilerContext& operator<<(eth::AssemblyItem const& _item) { m_asm.append(_item); return *this; }
CompilerContext& operator<<(eth::Instruction _instruction) { m_asm.append(_instruction); return *this; }
CompilerContext& operator<<(u256 const& _value) { m_asm.append(_value); return *this; }
CompilerContext& operator<<(bytes const& _data) { m_asm.append(_data); return *this; }
void optimise(unsigned _runs = 200) { m_asm.optimise(true, true, _runs); }
eth::Assembly const& getAssembly() const { return m_asm; }
/// @arg _sourceCodes is the map of input files to source code strings
/// @arg _inJsonFormat shows whether the out should be in Json format
Json::Value streamAssembly(std::ostream& _stream, StringMap const& _sourceCodes = StringMap(), bool _inJsonFormat = false) const
{
return m_asm.stream(_stream, "", _sourceCodes, _inJsonFormat);
}
bytes getAssembledBytecode() { return m_asm.assemble(); }
bytes getAssembledRuntimeBytecode(size_t _subIndex) { m_asm.assemble(); return m_asm.data(u256(_subIndex)); }
/**
* Helper class to pop the visited nodes stack when a scope closes
*/
class LocationSetter: public ScopeGuard
{
public:
LocationSetter(CompilerContext& _compilerContext, ASTNode const& _node):
ScopeGuard([&]{ _compilerContext.popVisitedNodes(); }) { _compilerContext.pushVisitedNodes(&_node); }
};
private:
/// @returns the entry label of the given function - searches the inheritance hierarchy
/// startig from the given point towards the base.
eth::AssemblyItem getVirtualFunctionEntryLabel(
FunctionDefinition const& _function,
std::vector<ContractDefinition const*>::const_iterator _searchStart
);
/// @returns an iterator to the contract directly above the given contract.
std::vector<ContractDefinition const*>::const_iterator getSuperContract(const ContractDefinition &_contract) const;
/// Updates source location set in the assembly.
void updateSourceLocation();
eth::Assembly m_asm;
/// Magic global variables like msg, tx or this, distinguished by type.
std::set<Declaration const*> m_magicGlobals;
/// Other already compiled contracts to be used in contract creation calls.
std::map<ContractDefinition const*, bytes const*> m_compiledContracts;
/// Storage offsets of state variables
std::map<Declaration const*, std::pair<u256, unsigned>> m_stateVariables;
/// Offsets of local variables on the stack (relative to stack base).
std::map<Declaration const*, unsigned> m_localVariables;
/// Labels pointing to the entry points of functions.
std::map<Declaration const*, eth::AssemblyItem> m_functionEntryLabels;
/// Set of functions for which we did not yet generate code.
std::set<Declaration const*> m_functionsWithCode;
/// List of current inheritance hierarchy from derived to base.
std::vector<ContractDefinition const*> m_inheritanceHierarchy;
/// Stack of current visited AST nodes, used for location attachment
std::stack<ASTNode const*> m_visitedNodes;
};
}
}
