libyul/optimiser/Semantics.cpp


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/*(
    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/>.
*/
/**
 * Specific AST walkers that collect semantical facts.
 */

#include <libyul/optimiser/Semantics.h>

#include <libyul/Exceptions.h>
#include <libyul/AsmData.h>
#include <libyul/Dialect.h>

#include <libevmasm/SemanticInformation.h>

#include <libdevcore/CommonData.h>

using namespace std;
using namespace dev;
using namespace yul;

MovableChecker::MovableChecker(Dialect const& _dialect):
    m_dialect(_dialect)
{
}

MovableChecker::MovableChecker(Dialect const& _dialect, Expression const& _expression):
    MovableChecker(_dialect)
{
    visit(_expression);
}

void MovableChecker::operator()(Identifier const& _identifier)
{
    ASTWalker::operator()(_identifier);
    m_variableReferences.emplace(_identifier.name);
}

void MovableChecker::operator()(FunctionalInstruction const& _instr)
{
    if (!eth::SemanticInformation::movable(_instr.instruction))
        m_movable = false;
    else
        ASTWalker::operator()(_instr);
}

void MovableChecker::operator()(FunctionCall const& _functionCall)
{
    if (BuiltinFunction const* f = m_dialect.builtin(_functionCall.functionName.name))
        if (f->movable)
        {
            ASTWalker::operator()(_functionCall);
            return;
        }
    m_movable = false;
}

void MovableChecker::visit(Statement const&)
{
    assertThrow(false, OptimizerException, "Movability for statement requested.");
}