/*

  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

#include <libsolutil/Numeric.h>

#include <liblangutil/Exceptions.h>

using namespace solidity;

bool solidity::fitsPrecisionBaseX(bigint const& _mantissa, double _log2OfBase, uint32_t _exp)

{

  if (_mantissa == 0)

    return true;

  solAssert(_mantissa > 0, "");

  size_t const bitsMax = 4096;

  size_t mostSignificantMantissaBit = static_cast<size_t>(boost::multiprecision::msb(_mantissa));

  if (mostSignificantMantissaBit > bitsMax) // _mantissa >= 2 ^ 4096

    return false;

  bigint bitsNeeded = mostSignificantMantissaBit + bigint(floor(double(_exp) * _log2OfBase)) + 1;

  return bitsNeeded <= bitsMax;

}