solidity/libyul/optimiser/LoadResolver.h
2019-09-04 19:16:54 +02:00

71 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/>.
*/
/**
* Optimisation stage that replaces expressions of type ``sload(x)`` by the value
* currently stored in storage, if known.
*/
#pragma once
#include <libyul/optimiser/DataFlowAnalyzer.h>
#include <libevmasm/Instruction.h>
namespace yul
{
struct EVMDialect;
struct BuiltinFunctionForEVM;
/**
* Optimisation stage that replaces expressions of type ``sload(x)`` and ``mload(x)`` by the value
* currently stored in storage resp. memory, if known.
*
* Works best if the code is in SSA form.
*
* Prerequisite: Disambiguator, ForLoopInitRewriter.
*/
class LoadResolver: public DataFlowAnalyzer
{
public:
/// Run the load resolver on the given complete AST.
static void run(Dialect const& _dialect, Block& _ast);
private:
LoadResolver(
Dialect const& _dialect,
std::map<YulString, SideEffects> _functionSideEffects,
bool _optimizeMLoad
):
DataFlowAnalyzer(_dialect, std::move(_functionSideEffects)),
m_optimizeMLoad(_optimizeMLoad)
{}
protected:
using ASTModifier::visit;
void visit(Expression& _e) override;
void tryResolve(
Expression& _e,
dev::eth::Instruction _instruction,
std::vector<Expression> const& _arguments
);
bool m_optimizeMLoad = false;
};
}