solidity/libyul/optimiser/BlockHasher.h

109 lines
2.9 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/>.
*/
/**
* Optimiser component that calculates hash values for block prefixes.
*/
#pragma once
#include <libyul/optimiser/ASTWalker.h>
#include <libyul/AsmDataForward.h>
#include <libyul/YulString.h>
#include <libyul/AsmData.h>
namespace yul
{
struct BlockPart {
Block const* block;
size_t length;
bool operator<(BlockPart const& _rhs) const
{
return std::make_tuple(_rhs.length, _rhs.block) < std::make_tuple(length, block);
}
};
/**
* Optimiser component that calculates hash values for block prefixes.
*
* Prerequisite: Disambiguator
*/
class BlockHasher: public ASTWalker
{
public:
struct State {
std::map<BlockPart, uint64_t> blockPrefixHashes;
std::map<uint64_t, std::vector<BlockPart>> hashClasses;
};
using ASTWalker::operator();
void operator()(Literal const&) override;
void operator()(Identifier const&) override;
void operator()(FunctionalInstruction const& _instr) override;
void operator()(FunctionCall const& _funCall) override;
void operator()(ExpressionStatement const& _statement) override;
void operator()(Assignment const& _assignment) override;
void operator()(VariableDeclaration const& _varDecl) override;
void operator()(If const& _if) override;
void operator()(Switch const& _switch) override;
void operator()(FunctionDefinition const&) override;
void operator()(ForLoop const&) override;
void operator()(Break const&) override;
void operator()(Continue const&) override;
void operator()(Block const& _block) override;
static State run(Block const& _block);
private:
State& m_state;
BlockHasher(State& _state): m_state(_state) {}
void hash(uint8_t _value)
{
m_hash *= 1099511628211u;
m_hash ^= _value;
}
void hash(uint16_t _value)
{
hash(static_cast<uint8_t>(_value & 0xFF));
hash(static_cast<uint8_t>(_value >> 8));
}
void hash(uint32_t _value)
{
hash(static_cast<uint8_t>(_value & 0xFFFF));
hash(static_cast<uint8_t>(_value >> 16));
}
void hash(uint64_t _value)
{
hash(static_cast<uint8_t>(_value & 0xFFFFFFFF));
hash(static_cast<uint8_t>(_value >> 32));
}
uint64_t m_hash = 14695981039346656037u;
struct VariableReference {
size_t id = 0;
bool isExternal = false;
};
std::map<YulString, VariableReference> m_variableReferences;
size_t m_externalIdentifierCount = 0;
size_t m_internalIdentifierCount = 0;
};
}