path: root/CompilerContext.cpp

/*
    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.
 */

#include <utility>
#include <numeric>
#include <libsolidity/AST.h>
#include <libsolidity/Compiler.h>

using namespace std;

namespace dev
{
namespace solidity
{

void CompilerContext::addMagicGlobal(MagicVariableDeclaration const& _declaration)
{
    m_magicGlobals.insert(&_declaration);
}

void CompilerContext::addStateVariable(
    VariableDeclaration const& _declaration,
    u256 const& _storageOffset,
    unsigned _byteOffset
)
{
    m_stateVariables[&_declaration] = make_pair(_storageOffset, _byteOffset);
}

void CompilerContext::startFunction(Declaration const& _function)
{
    m_functionsWithCode.insert(&_function);
    *this << getFunctionEntryLabel(_function);
}

void CompilerContext::addVariable(VariableDeclaration const& _declaration,
                                  unsigned _offsetToCurrent)
{
    solAssert(m_asm.deposit() >= 0 && unsigned(m_asm.deposit()) >= _offsetToCurrent, "");
    m_localVariables[&_declaration] = unsigned(m_asm.deposit()) - _offsetToCurrent;
}

void CompilerContext::removeVariable(VariableDeclaration const& _declaration)
{
    solAssert(!!m_localVariables.count(&_declaration), "");
    m_localVariables.erase(&_declaration);
}

void CompilerContext::addAndInitializeVariable(VariableDeclaration const& _declaration)
{
    LocationSetter locationSetter(*this, _declaration);
    addVariable(_declaration);
    int const size = _declaration.getType()->getSizeOnStack();
    for (int i = 0; i < size; ++i)
        *this << u256(0);
}

bytes const& CompilerContext::getCompiledContract(const ContractDefinition& _contract) const
{
    auto ret = m_compiledContracts.find(&_contract);
    solAssert(ret != m_compiledContracts.end(), "Compiled contract not found.");
    return *ret->second;
}

bool CompilerContext::isLocalVariable(Declaration const* _declaration) const
{
    return !!m_localVariables.count(_declaration);
}

eth::AssemblyItem CompilerContext::getFunctionEntryLabel(Declaration const& _declaration)
{
    auto res = m_functionEntryLabels.find(&_declaration);
    if (res == m_functionEntryLabels.end())
    {
        eth::AssemblyItem tag(m_asm.newTag());
        m_functionEntryLabels.insert(make_pair(&_declaration, tag));
        return tag.tag();
    }
    else
        return res->second.tag();
}

eth::AssemblyItem CompilerContext::getVirtualFunctionEntryLabel(FunctionDefinition const& _function)
{
    solAssert(!m_inheritanceHierarchy.empty(), "No inheritance hierarchy set.");
    return getVirtualFunctionEntryLabel(_function, m_inheritanceHierarchy.begin());
}

eth::AssemblyItem CompilerContext::getSuperFunctionEntryLabel(FunctionDefinition const& _function, ContractDefinition const& _base)
{
    solAssert(!m_inheritanceHierarchy.empty(), "No inheritance hierarchy set.");
    return getVirtualFunctionEntryLabel(_function, getSuperContract(_base));
}

FunctionDefinition const* CompilerContext::getNextConstructor(ContractDefinition const& _contract) const
{
    vector<ContractDefinition const*>::const_iterator it = getSuperContract(_contract);
    for (; it != m_inheritanceHierarchy.end(); ++it)
        if ((*it)->getConstructor())
            return (*it)->getConstructor();

    return nullptr;
}

set<Declaration const*> CompilerContext::getFunctionsWithoutCode()
{
    set<Declaration const*> functions;
    for (auto const& it: m_functionEntryLabels)
        if (m_functionsWithCode.count(it.first) == 0)
            functions.insert(it.first);
    return move(functions);
}

ModifierDefinition const& CompilerContext::getFunctionModifier(string const& _name) const
{
    solAssert(!m_inheritanceHierarchy.empty(), "No inheritance hierarchy set.");
    for (ContractDefinition const* contract: m_inheritanceHierarchy)
        for (ASTPointer<ModifierDefinition> const& modifier: contract->getFunctionModifiers())
            if (modifier->getName() == _name)
                return *modifier.get();
    BOOST_THROW_EXCEPTION(InternalCompilerError()
                          << errinfo_comment("Function modifier " + _name + " not found."));
}

unsigned CompilerContext::getBaseStackOffsetOfVariable(Declaration const& _declaration) const
{
    auto res = m_localVariables.find(&_declaration);
    solAssert(res != m_localVariables.end(), "Variable not found on stack.");
    return res->second;
}

unsigned CompilerContext::baseToCurrentStackOffset(unsigned _baseOffset) const
{
    return m_asm.deposit() - _baseOffset - 1;
}

unsigned CompilerContext::currentToBaseStackOffset(unsigned _offset) const
{
    return m_asm.deposit() - _offset - 1;
}

pair<u256, unsigned> CompilerContext::getStorageLocationOfVariable(const Declaration& _declaration) const
{
    auto it = m_stateVariables.find(&_declaration);
    solAssert(it != m_stateVariables.end(), "Variable not found in storage.");
    return it->second;
}

CompilerContext& CompilerContext::appendJump(eth::AssemblyItem::JumpType _jumpType)
{
    eth::AssemblyItem item(eth::Instruction::JUMP);
    item.setJumpType(_jumpType);
    return *this << item;
}

void CompilerContext::resetVisitedNodes(ASTNode const* _node)
{
    stack<ASTNode const*> newStack;
    newStack.push(_node);
    std::swap(m_visitedNodes, newStack);
    updateSourceLocation();
}

eth::AssemblyItem CompilerContext::getVirtualFunctionEntryLabel(
    FunctionDefinition const& _function,
    vector<ContractDefinition const*>::const_iterator _searchStart
)
{
    string name = _function.getName();
    FunctionType functionType(_function);
    auto it = _searchStart;
    for (; it != m_inheritanceHierarchy.end(); ++it)
        for (ASTPointer<FunctionDefinition> const& function: (*it)->getDefinedFunctions())
            if (
                function->getName() == name &&
                !function->isConstructor() &&
                FunctionType(*function).hasEqualArgumentTypes(functionType)
            )
                return getFunctionEntryLabel(*function);
    solAssert(false, "Super function " + name + " not found.");
    return m_asm.newTag(); // not reached
}

vector<ContractDefinition const*>::const_iterator CompilerContext::getSuperContract(ContractDefinition const& _contract) const
{
    solAssert(!m_inheritanceHierarchy.empty(), "No inheritance hierarchy set.");
    auto it = find(m_inheritanceHierarchy.begin(), m_inheritanceHierarchy.end(), &_contract);
    solAssert(it != m_inheritanceHierarchy.end(), "Base not found in inheritance hierarchy.");
    return ++it;
}

void CompilerContext::updateSourceLocation()
{
    m_asm.setSourceLocation(m_visitedNodes.empty() ? SourceLocation() : m_visitedNodes.top()->getLocation());
}

}
}