path: root/libsolidity/codegen/AsmCodeGen.cpp

/*
    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/>.
*/
/**
 * Adaptor between the abstract assembly and eth assembly.
 */

#include <libsolidity/codegen/AsmCodeGen.h>

#include <libyul/AsmData.h>
#include <libyul/AsmAnalysisInfo.h>

#include <libyul/backends/evm/AbstractAssembly.h>
#include <libyul/backends/evm/EVMCodeTransform.h>

#include <libevmasm/Assembly.h>
#include <libevmasm/AssemblyItem.h>
#include <libevmasm/Instruction.h>

#include <liblangutil/SourceLocation.h>

#include <libdevcore/FixedHash.h>

#include <memory>
#include <functional>

using namespace std;
using namespace dev;
using namespace langutil;
using namespace yul;
using namespace dev::solidity;

EthAssemblyAdapter::EthAssemblyAdapter(eth::Assembly& _assembly):
    m_assembly(_assembly)
{
}

void EthAssemblyAdapter::setSourceLocation(SourceLocation const& _location)
{
    m_assembly.setSourceLocation(_location);
}

int EthAssemblyAdapter::stackHeight() const
{
    return m_assembly.deposit();
}

void EthAssemblyAdapter::appendInstruction(solidity::Instruction _instruction)
{
    m_assembly.append(_instruction);
}

void EthAssemblyAdapter::appendConstant(u256 const& _constant)
{
    m_assembly.append(_constant);
}

void EthAssemblyAdapter::appendLabel(LabelID _labelId)
{
    m_assembly.append(eth::AssemblyItem(eth::Tag, _labelId));
}

void EthAssemblyAdapter::appendLabelReference(LabelID _labelId)
{
    m_assembly.append(eth::AssemblyItem(eth::PushTag, _labelId));
}

size_t EthAssemblyAdapter::newLabelId()
{
    return assemblyTagToIdentifier(m_assembly.newTag());
}

size_t EthAssemblyAdapter::namedLabel(std::string const& _name)
{
    return assemblyTagToIdentifier(m_assembly.namedTag(_name));
}

void EthAssemblyAdapter::appendLinkerSymbol(std::string const& _linkerSymbol)
{
    m_assembly.appendLibraryAddress(_linkerSymbol);
}

void EthAssemblyAdapter::appendJump(int _stackDiffAfter)
{
    appendInstruction(solidity::Instruction::JUMP);
    m_assembly.adjustDeposit(_stackDiffAfter);
}

void EthAssemblyAdapter::appendJumpTo(LabelID _labelId, int _stackDiffAfter)
{
    appendLabelReference(_labelId);
    appendJump(_stackDiffAfter);
}

void EthAssemblyAdapter::appendJumpToIf(LabelID _labelId)
{
    appendLabelReference(_labelId);
    appendInstruction(solidity::Instruction::JUMPI);
}

void EthAssemblyAdapter::appendBeginsub(LabelID, int)
{
    // TODO we could emulate that, though
    solAssert(false, "BEGINSUB not implemented for EVM 1.0");
}

void EthAssemblyAdapter::appendJumpsub(LabelID, int, int)
{
    // TODO we could emulate that, though
    solAssert(false, "JUMPSUB not implemented for EVM 1.0");
}

void EthAssemblyAdapter::appendReturnsub(int, int)
{
    // TODO we could emulate that, though
    solAssert(false, "RETURNSUB not implemented for EVM 1.0");
}

void EthAssemblyAdapter::appendAssemblySize()
{
    m_assembly.appendProgramSize();
}

pair<shared_ptr<AbstractAssembly>, AbstractAssembly::SubID> EthAssemblyAdapter::createSubAssembly()
{
    shared_ptr<eth::Assembly> assembly{make_shared<eth::Assembly>()};
    auto sub = m_assembly.newSub(assembly);
    return {make_shared<EthAssemblyAdapter>(*assembly), size_t(sub.data())};
}

void EthAssemblyAdapter::appendDataOffset(AbstractAssembly::SubID _sub)
{
    auto it = m_dataHashBySubId.find(_sub);
    if (it == m_dataHashBySubId.end())
        m_assembly.pushSubroutineOffset(size_t(_sub));
    else
        m_assembly << eth::AssemblyItem(eth::PushData, it->second);
}

void EthAssemblyAdapter::appendDataSize(AbstractAssembly::SubID _sub)
{
    auto it = m_dataHashBySubId.find(_sub);
    if (it == m_dataHashBySubId.end())
        m_assembly.pushSubroutineSize(size_t(_sub));
    else
        m_assembly << u256(m_assembly.data(h256(it->second)).size());
}

AbstractAssembly::SubID EthAssemblyAdapter::appendData(bytes const& _data)
{
    eth::AssemblyItem pushData = m_assembly.newData(_data);
    SubID subID = m_nextDataCounter++;
    m_dataHashBySubId[subID] = pushData.data();
    return subID;
}

EthAssemblyAdapter::LabelID EthAssemblyAdapter::assemblyTagToIdentifier(eth::AssemblyItem const& _tag)
{
    u256 id = _tag.data();
    solAssert(id <= std::numeric_limits<LabelID>::max(), "Tag id too large.");
    return LabelID(id);
}

void CodeGenerator::assemble(
    Block const& _parsedData,
    AsmAnalysisInfo& _analysisInfo,
    eth::Assembly& _assembly,
    ExternalIdentifierAccess const& _identifierAccess,
    bool _useNamedLabelsForFunctions
)
{
    EthAssemblyAdapter assemblyAdapter(_assembly);
    CodeTransform(
        assemblyAdapter,
        _analysisInfo,
        false,
        false,
        _identifierAccess,
        _useNamedLabelsForFunctions
    )(_parsedData);
}