solidity/libyul/optimiser/ForLoopConditionOutOfBody.h
2019-09-24 14:52:01 +02:00

75 lines
1.6 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/>.
*/
#pragma once
#include <libyul/optimiser/ASTWalker.h>
#include <libyul/optimiser/OptimiserStep.h>
#include <libyul/Dialect.h>
namespace yul
{
/**
* Reverses the transformation of ForLoopConditionIntoBody.
*
* For any movable ``c``, it turns
*
* for { ... } 1 { ... } {
* if iszero(c) { break }
* ...
* }
*
* into
*
* for { ... } c { ... } {
* ...
* }
*
* and it turns
*
* for { ... } 1 { ... } {
* if c { break }
* ...
* }
*
* into
*
* for { ... } iszero(c) { ... } {
* ...
* }
*
* The LiteralRematerialiser should be run before this step.
*/
class ForLoopConditionOutOfBody: public ASTModifier
{
public:
static constexpr char const* name{"ForLoopConditionOutOfBody"};
static void run(OptimiserStepContext&, Block& _ast);
using ASTModifier::operator();
void operator()(ForLoop& _forLoop) override;
private:
ForLoopConditionOutOfBody(Dialect const& _dialect):
m_dialect(_dialect)
{}
Dialect const& m_dialect;
};
}