solidity/libjulia/optimiser/CommonSubexpressionEliminator.cpp
2018-05-09 12:28:49 +02:00

50 lines
1.5 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/>.
*/
/**
* Optimisation stage that replaces expressions known to be the current value of a variable
* in scope by a reference to that variable.
*/
#include <libjulia/optimiser/CommonSubexpressionEliminator.h>
#include <libjulia/optimiser/Metrics.h>
#include <libjulia/optimiser/SyntacticalEquality.h>
#include <libjulia/Exceptions.h>
#include <libsolidity/inlineasm/AsmData.h>
using namespace std;
using namespace dev;
using namespace dev::julia;
void CommonSubexpressionEliminator::visit(Expression& _e)
{
// Single exception for substitution: We do not substitute one variable for another.
if (_e.type() != typeid(Identifier))
// TODO this search rather inefficient.
for (auto const& var: m_value)
{
assertThrow(var.second, OptimizerException, "");
if (SyntacticalEqualityChecker::equal(_e, *var.second))
{
_e = Identifier{locationOf(_e), var.first};
break;
}
}
DataFlowAnalyzer::visit(_e);
}