/*

  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/>.

*/

// SPDX-License-Identifier: GPL-3.0

/**

 * Optimiser component that renames identifiers to free up certain names.

 */

#include <libyul/optimiser/NameDisplacer.h>

#include <libyul/AST.h>

using namespace solidity;

using namespace solidity::yul;

void NameDisplacer::operator()(Identifier& _identifier)

{

  checkAndReplace(_identifier.name);

}

void NameDisplacer::operator()(VariableDeclaration& _varDecl)

{

  for (NameWithDebugData& var: _varDecl.variables)

    checkAndReplaceNew(var.name);

  ASTModifier::operator()(_varDecl);

}

void NameDisplacer::operator()(FunctionDefinition& _function)

{

  // Should have been done in the block already.

  yulAssert(!m_namesToFree.count(_function.name), "");

  for (auto& param: _function.parameters)

    checkAndReplaceNew(param.name);

  for (auto& retVar: _function.returnVariables)

    checkAndReplaceNew(retVar.name);

  ASTModifier::operator()(_function);

}

void NameDisplacer::operator()(FunctionCall& _funCall)

{

  if (std::holds_alternative<Identifier>(_funCall.functionName))

    checkAndReplace(std::get<Identifier>(_funCall.functionName).name);

  ASTModifier::operator()(_funCall);

}

void NameDisplacer::operator()(Block& _block)

{

  // First replace all the names of function definitions

  // because of scoping.

  for (auto& st: _block.statements)

    if (std::holds_alternative<FunctionDefinition>(st))

      checkAndReplaceNew(std::get<FunctionDefinition>(st).name);

  ASTModifier::operator()(_block);

}

void NameDisplacer::checkAndReplaceNew(YulName& _name)

{

  yulAssert(!m_translations.count(_name), "");

  if (m_namesToFree.count(_name))

    _name = (m_translations[_name] = m_nameDispenser.newName(_name));

}

void NameDisplacer::checkAndReplace(YulName& _name) const

{

  if (m_translations.count(_name))

    _name = m_translations.at(_name);

}