solidity/libyul/optimiser/NameDispenser.h
2019-06-19 14:55:38 +02:00

62 lines
1.8 KiB
C++

/*
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/>.
*/
/**
* Optimiser component that can create new unique names.
*/
#pragma once
#include <libyul/AsmDataForward.h>
#include <libyul/YulString.h>
#include <set>
namespace yul
{
struct Dialect;
/**
* Optimizer component that can be used to generate new names that
* do not conflict with existing names.
*
* Tries to keep names short and appends decimals to disambiguate.
*/
class NameDispenser
{
public:
/// Initialize the name dispenser with all the names used in the given AST.
explicit NameDispenser(Dialect const& _dialect, Block const& _ast, std::set<YulString> _reservedNames = {});
/// Initialize the name dispenser with the given used names.
explicit NameDispenser(Dialect const& _dialect, std::set<YulString> _usedNames);
/// @returns a currently unused name that should be similar to _nameHint.
YulString newName(YulString _nameHint);
/// Mark @a _name as used, i.e. the dispenser's newName function will not
/// return it.
void markUsed(YulString _name) { m_usedNames.insert(_name); }
private:
bool illegalName(YulString _name);
Dialect const& m_dialect;
std::set<YulString> m_usedNames;
size_t m_counter = 0;
};
}