/*

  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

#pragma once

#include <libsmtutil/SolverInterface.h>

namespace solidity::smtutil

{

/// Signed division in SMTLIB2 rounds differently than EVM.

/// This does not check for division by zero!

inline Expression signedDivisionEVM(Expression _left, Expression _right)

{

  return Expression::ite(

    _left >= 0,

    Expression::ite(_right >= 0, _left / _right, 0 - (_left / (0 - _right))),

    Expression::ite(_right >= 0, 0 - ((0 - _left) / _right), (0 - _left) / (0 - _right))

  );

}

inline Expression abs(Expression _value)

{

  return Expression::ite(_value >= 0, _value, 0 - _value);

}

/// Signed modulo in SMTLIB2 behaves differently with regards

/// to the sign than EVM.

/// This does not check for modulo by zero!

inline Expression signedModuloEVM(Expression _left, Expression _right)

{

  return Expression::ite(

    _left >= 0,

    _left % _right,

    Expression::ite(

      (_left % _right) == 0,

      0,

      (_left % _right) - abs(_right)

    )

  );

}

}