mirror of
https://github.com/ethereum/solidity
synced 2023-10-03 13:03:40 +00:00
71 lines
2.2 KiB
C++
71 lines
2.2 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 variables by their most recently assigned expressions.
|
|
*/
|
|
|
|
#include <libyul/optimiser/Rematerialiser.h>
|
|
|
|
#include <libyul/optimiser/Metrics.h>
|
|
#include <libyul/optimiser/ASTCopier.h>
|
|
#include <libyul/optimiser/NameCollector.h>
|
|
#include <libyul/Exceptions.h>
|
|
#include <libyul/AsmData.h>
|
|
|
|
using namespace std;
|
|
using namespace dev;
|
|
using namespace yul;
|
|
|
|
void Rematerialiser::run(Dialect const& _dialect, Block& _ast)
|
|
{
|
|
Rematerialiser{_dialect, _ast}(_ast);
|
|
}
|
|
|
|
Rematerialiser::Rematerialiser(Dialect const& _dialect, Block& _ast):
|
|
DataFlowAnalyzer(_dialect),
|
|
m_referenceCounts(ReferencesCounter::countReferences(_ast))
|
|
{
|
|
}
|
|
|
|
void Rematerialiser::visit(Expression& _e)
|
|
{
|
|
if (_e.type() == typeid(Identifier))
|
|
{
|
|
Identifier& identifier = boost::get<Identifier>(_e);
|
|
if (m_value.count(identifier.name))
|
|
{
|
|
YulString name = identifier.name;
|
|
assertThrow(m_value.at(name), OptimizerException, "");
|
|
auto const& value = *m_value.at(name);
|
|
size_t refs = m_referenceCounts[name];
|
|
size_t cost = CodeCost::codeCost(value);
|
|
if (refs <= 1 || cost == 0 || (refs <= 5 && cost <= 1))
|
|
{
|
|
assertThrow(m_referenceCounts[name] > 0, OptimizerException, "");
|
|
for (auto const& ref: m_references[name])
|
|
assertThrow(inScope(ref), OptimizerException, "");
|
|
// update reference counts
|
|
m_referenceCounts[name]--;
|
|
for (auto const& ref: ReferencesCounter::countReferences(value))
|
|
m_referenceCounts[ref.first] += ref.second;
|
|
_e = (ASTCopier{}).translate(value);
|
|
}
|
|
}
|
|
}
|
|
DataFlowAnalyzer::visit(_e);
|
|
}
|