solidity/libsolidity/analysis/VariableCanBeImmutable.cpp

126 lines
3.7 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/>.
*/
// SPDX-License-Identifier: GPL-3.0
#include <libsolidity/analysis/VariableCanBeImmutable.h>
#include <libsolidity/ast/AST.h>
#include <libsolidity/ast/CallGraph.h>
#include <libsolutil/Algorithms.h>
#include <liblangutil/ErrorReporter.h>
#include <range/v3/view/transform.hpp>
#include <range/v3/view/filter.hpp>
#include <range/v3/range/conversion.hpp>
#include <map>
using namespace std;
using namespace solidity;
using namespace solidity::langutil;
using namespace solidity::frontend;
bool VariableCanBeImmutable::visit(ContractDefinition const& _contractDefinition)
{
m_contract = &_contractDefinition;
auto const& edges = (*_contractDefinition.annotation().deployedCallGraph)->edges;
frontend::CallGraph::Node _node = frontend::CallGraph::SpecialNode::Entry;
// A contract with no additional functions
if (!edges.count(_node))
return true;
auto functions =
edges.at(_node) |
ranges::views::transform(
[](auto const& _node) -> optional<FunctionDefinition const*>
{
auto callable = get<CallableDeclaration const*>(_node);
solAssert(callable, "");
if (auto functionDefinition = dynamic_cast<FunctionDefinition const*>(callable))
return functionDefinition;
return std::nullopt;
}
) |
ranges::views::filter([](auto const& _optional) { return _optional.has_value(); }) |
ranges::views::transform([](auto const& _optional) { return *_optional; }) |
ranges::to<list<FunctionDefinition const*>>
;
m_reachableFunctions = util::BreadthFirstSearch<FunctionDefinition const*>{functions}.run(
[&](FunctionDefinition const* _function, auto&& _addChild)
{
for (CallGraph::Node const& node: edges.at(_function))
{
auto callable = get<CallableDeclaration const*>(node);
solAssert(callable, "");
if (auto function = dynamic_cast<FunctionDefinition const*>(callable))
_addChild(function);
}
}
).visited;
return true;
}
void VariableCanBeImmutable::endVisit(ContractDefinition const& _contractDefinition)
{
for (auto const& variable: _contractDefinition.stateVariables())
if (
!variable->immutable() &&
!m_variablesWrittenTo.count(variable) &&
!variable->isConstant()
)
m_errorReporter.warning(
0000_error,
variable->location(),
"Variable declaration can be converted into an immutable."
);
m_variablesWrittenTo.clear();
m_contract = nullptr;
}
bool VariableCanBeImmutable::visit(FunctionDefinition const& _functionDefinition)
{
m_function = &_functionDefinition;
return true;
}
void VariableCanBeImmutable::endVisit(FunctionDefinition const& )
{
m_function = nullptr;
}
void VariableCanBeImmutable::endVisit(Identifier const& _identifier)
{
Declaration const* declaration = _identifier.annotation().referencedDeclaration;
solAssert(declaration, "");
bool writes = _identifier.annotation().willBeWrittenTo;
if (VariableDeclaration const* varDecl = dynamic_cast<VariableDeclaration const*>(declaration))
if (
writes &&
!varDecl->immutable() &&
varDecl->isStateVariable() &&
!varDecl->isConstant()
)
{
solAssert(m_contract, "");
if (m_function && m_reachableFunctions.count(m_function))
m_variablesWrittenTo.insert(varDecl);
}
}