solidity/libyul/optimiser/NameCollector.h
2020-04-02 18:00:44 -05:00

117 lines
3.4 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/>.
*/
/**
* Specific AST walkers that collect facts about identifiers and definitions.
*/
#pragma once
#include <libyul/optimiser/ASTWalker.h>
#include <map>
#include <set>
namespace solidity::yul
{
/**
* Specific AST walker that collects all defined names.
*/
class NameCollector: public ASTWalker
{
public:
explicit NameCollector(Block const& _block)
{
(*this)(_block);
}
using ASTWalker::operator ();
void operator()(VariableDeclaration const& _varDecl) override;
void operator()(FunctionDefinition const& _funDef) override;
std::set<YulString> names() const { return m_names; }
private:
std::set<YulString> m_names;
};
/**
* Specific AST walker that counts all references to all declarations.
*/
class ReferencesCounter: public ASTWalker
{
public:
enum CountWhat { VariablesAndFunctions, OnlyVariables };
explicit ReferencesCounter(CountWhat _countWhat = VariablesAndFunctions):
m_countWhat(_countWhat)
{}
using ASTWalker::operator ();
void operator()(Identifier const& _identifier) override;
void operator()(FunctionCall const& _funCall) override;
static std::map<YulString, size_t> countReferences(Block const& _block, CountWhat _countWhat = VariablesAndFunctions);
static std::map<YulString, size_t> countReferences(FunctionDefinition const& _function, CountWhat _countWhat = VariablesAndFunctions);
static std::map<YulString, size_t> countReferences(Expression const& _expression, CountWhat _countWhat = VariablesAndFunctions);
std::map<YulString, size_t> const& references() const { return m_references; }
private:
CountWhat m_countWhat = CountWhat::VariablesAndFunctions;
std::map<YulString, size_t> m_references;
};
/**
* Specific AST walker that finds all variables that are assigned to.
*/
class Assignments: public ASTWalker
{
public:
using ASTWalker::operator ();
void operator()(Assignment const& _assignment) override;
std::set<YulString> const& names() const { return m_names; }
private:
std::set<YulString> m_names;
};
/**
* Collects all names from a given continue statement on onwards.
*
* It makes only sense to be invoked from within a body of an outer for loop, that is,
* it will only collect all names from the beginning of the first continue statement
* of the outer-most ForLoop.
*/
class AssignmentsSinceContinue: public ASTWalker
{
public:
using ASTWalker::operator();
void operator()(ForLoop const& _forLoop) override;
void operator()(Continue const&) override;
void operator()(Assignment const& _assignment) override;
void operator()(FunctionDefinition const& _funDef) override;
std::set<YulString> const& names() const { return m_names; }
bool empty() const noexcept { return m_names.empty(); }
private:
size_t m_forLoopDepth = 0;
bool m_continueFound = false;
std::set<YulString> m_names;
};
}