path: root/libsolidity/inlineasm/AsmAnalysis.h

/*
    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/>.
*/
/**
 * Analysis part of inline assembly.
 */

#pragma once

#include <libsolidity/interface/Exceptions.h>

#include <libsolidity/inlineasm/AsmScope.h>

#include <libjulia/backends/evm/AbstractAssembly.h>

#include <libsolidity/inlineasm/AsmDataForward.h>

#include <boost/variant.hpp>

#include <functional>
#include <memory>

namespace dev
{
namespace solidity
{
class ErrorReporter;
namespace assembly
{

struct AsmAnalysisInfo;

/**
 * Performs the full analysis stage, calls the ScopeFiller internally, then resolves
 * references and performs other checks.
 * If all these checks pass, code generation should not throw errors.
 */
class AsmAnalyzer: public boost::static_visitor<bool>
{
public:
    explicit AsmAnalyzer(
        AsmAnalysisInfo& _analysisInfo,
        ErrorReporter& _errorReporter,
        AsmFlavour _flavour = AsmFlavour::Loose,
        julia::ExternalIdentifierAccess::Resolver const& _resolver = julia::ExternalIdentifierAccess::Resolver()
    ): m_resolver(_resolver), m_info(_analysisInfo), m_errorReporter(_errorReporter), m_flavour(_flavour) {}

    bool analyze(assembly::Block const& _block);

    bool operator()(assembly::Instruction const&);
    bool operator()(assembly::Literal const& _literal);
    bool operator()(assembly::Identifier const&);
    bool operator()(assembly::FunctionalInstruction const& _functionalInstruction);
    bool operator()(assembly::Label const& _label);
    bool operator()(assembly::ExpressionStatement const&);
    bool operator()(assembly::StackAssignment const&);
    bool operator()(assembly::Assignment const& _assignment);
    bool operator()(assembly::VariableDeclaration const& _variableDeclaration);
    bool operator()(assembly::FunctionDefinition const& _functionDefinition);
    bool operator()(assembly::FunctionCall const& _functionCall);
    bool operator()(assembly::If const& _if);
    bool operator()(assembly::Switch const& _switch);
    bool operator()(assembly::ForLoop const& _forLoop);
    bool operator()(assembly::Block const& _block);

private:
    /// Visits the statement and expects it to deposit one item onto the stack.
    bool expectExpression(Expression const& _expr);
    bool expectDeposit(int _deposit, int _oldHeight, SourceLocation const& _location);

    /// Verifies that a variable to be assigned to exists and has the same size
    /// as the value, @a _valueSize, unless that is equal to -1.
    bool checkAssignment(assembly::Identifier const& _assignment, size_t _valueSize = size_t(-1));

    Scope& scope(assembly::Block const* _block);
    void expectValidType(std::string const& type, SourceLocation const& _location);
    void warnOnInstructions(solidity::Instruction _instr, SourceLocation const& _location);

    int m_stackHeight = 0;
    julia::ExternalIdentifierAccess::Resolver m_resolver;
    Scope* m_currentScope = nullptr;
    /// Variables that are active at the current point in assembly (as opposed to
    /// "part of the scope but not yet declared")
    std::set<Scope::Variable const*> m_activeVariables;
    AsmAnalysisInfo& m_info;
    ErrorReporter& m_errorReporter;
    AsmFlavour m_flavour = AsmFlavour::Loose;
};

}
}
}