From d6cf8492312341bbbd8df0cc80cb1aa74e26b5f5 Mon Sep 17 00:00:00 2001 From: chriseth Date: Wed, 1 Apr 2015 11:48:34 +0200 Subject: [PATCH] Moved semantic information to its own file. --- libevmcore/CommonSubexpressionEliminator.cpp | 75 +------------ libevmcore/CommonSubexpressionEliminator.h | 17 +-- libevmcore/SemanticInformation.cpp | 107 +++++++++++++++++++ libevmcore/SemanticInformation.h | 50 +++++++++ 4 files changed, 160 insertions(+), 89 deletions(-) create mode 100644 libevmcore/SemanticInformation.cpp create mode 100644 libevmcore/SemanticInformation.h diff --git a/libevmcore/CommonSubexpressionEliminator.cpp b/libevmcore/CommonSubexpressionEliminator.cpp index 47bb5b512..5c6ba95af 100644 --- a/libevmcore/CommonSubexpressionEliminator.cpp +++ b/libevmcore/CommonSubexpressionEliminator.cpp @@ -24,7 +24,7 @@ #include #include #include -#include +#include using namespace std; using namespace dev; @@ -248,79 +248,6 @@ ExpressionClasses::Id CommonSubexpressionEliminator::loadFromMemory(ExpressionCl return m_memoryContent[_slot] = m_expressionClasses.find(Instruction::MLOAD, {_slot}, true, m_sequenceNumber); } -bool SemanticInformation::breaksBasicBlock(AssemblyItem const& _item) -{ - switch (_item.type()) - { - default: - case UndefinedItem: - case Tag: - return true; - case Push: - case PushString: - case PushTag: - case PushSub: - case PushSubSize: - case PushProgramSize: - case PushData: - return false; - case Operation: - { - if (isSwapInstruction(_item) || isDupInstruction(_item)) - return false; - if (_item.instruction() == Instruction::GAS || _item.instruction() == Instruction::PC) - return true; // GAS and PC assume a specific order of opcodes - if (_item.instruction() == Instruction::MSIZE) - return true; // msize is modified already by memory access, avoid that for now - if (_item.instruction() == Instruction::SHA3) - return true; //@todo: we have to compare sha3's not based on their memory addresses but on the memory content. - InstructionInfo info = instructionInfo(_item.instruction()); - if (_item.instruction() == Instruction::SSTORE) - return false; - if (_item.instruction() == Instruction::MSTORE) - return false; - //@todo: We do not handle the following memory instructions for now: - // calldatacopy, codecopy, extcodecopy, mstore8, - // msize (note that msize also depends on memory read access) - - // the second requirement will be lifted once it is implemented - return info.sideEffects || info.args > 2; - } - } -} - -bool SemanticInformation::isCommutativeOperation(AssemblyItem const& _item) -{ - if (_item.type() != Operation) - return false; - switch (_item.instruction()) - { - case Instruction::ADD: - case Instruction::MUL: - case Instruction::EQ: - case Instruction::AND: - case Instruction::OR: - case Instruction::XOR: - return true; - default: - return false; - } -} - -bool SemanticInformation::isDupInstruction(AssemblyItem const& _item) -{ - if (_item.type() != Operation) - return false; - return Instruction::DUP1 <= _item.instruction() && _item.instruction() <= Instruction::DUP16; -} - -bool SemanticInformation::isSwapInstruction(AssemblyItem const& _item) -{ - if (_item.type() != Operation) - return false; - return Instruction::SWAP1 <= _item.instruction() && _item.instruction() <= Instruction::SWAP16; -} - CSECodeGenerator::CSECodeGenerator( ExpressionClasses& _expressionClasses, vector const& _storeOperations diff --git a/libevmcore/CommonSubexpressionEliminator.h b/libevmcore/CommonSubexpressionEliminator.h index a9a0c60a4..0dbb47b29 100644 --- a/libevmcore/CommonSubexpressionEliminator.h +++ b/libevmcore/CommonSubexpressionEliminator.h @@ -31,6 +31,7 @@ #include #include #include +#include namespace dev { @@ -139,20 +140,6 @@ private: AssemblyItem const* m_breakingItem = nullptr; }; -/** - * Helper functions to provide context-independent information about assembly items. - */ -struct SemanticInformation -{ - /// @returns true if the given items starts a new basic block - static bool breaksBasicBlock(AssemblyItem const& _item); - /// @returns true if the item is a two-argument operation whose value does not depend on the - /// order of its arguments. - static bool isCommutativeOperation(AssemblyItem const& _item); - static bool isDupInstruction(AssemblyItem const& _item); - static bool isSwapInstruction(AssemblyItem const& _item); -}; - /** * Unit that generates code from current stack layout, target stack layout and information about * the equivalence classes. @@ -230,7 +217,7 @@ _AssemblyItemIterator CommonSubexpressionEliminator::feedItems( _AssemblyItemIterator _end ) { - for (; _iterator != _end && !SemanticInformation::breaksBasicBlock(*_iterator); ++_iterator) + for (; _iterator != _end && !SemanticInformation::breaksCSEAnalysisBlock(*_iterator); ++_iterator) feedItem(*_iterator); if (_iterator != _end) m_breakingItem = &(*_iterator++); diff --git a/libevmcore/SemanticInformation.cpp b/libevmcore/SemanticInformation.cpp new file mode 100644 index 000000000..e561e7554 --- /dev/null +++ b/libevmcore/SemanticInformation.cpp @@ -0,0 +1,107 @@ +/* + This file is part of cpp-ethereum. + + cpp-ethereum 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. + + cpp-ethereum 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 cpp-ethereum. If not, see . +*/ +/** + * @file SemanticInformation.cpp + * @author Christian + * @date 2015 + * Helper to provide semantic information about assembly items. + */ + +#include +#include + +using namespace std; +using namespace dev; +using namespace dev::eth; + +bool SemanticInformation::breaksCSEAnalysisBlock(AssemblyItem const& _item) +{ + switch (_item.type()) + { + default: + case UndefinedItem: + case Tag: + return true; + case Push: + case PushString: + case PushTag: + case PushSub: + case PushSubSize: + case PushProgramSize: + case PushData: + return false; + case Operation: + { + if (isSwapInstruction(_item) || isDupInstruction(_item)) + return false; + if (_item.instruction() == Instruction::GAS || _item.instruction() == Instruction::PC) + return true; // GAS and PC assume a specific order of opcodes + if (_item.instruction() == Instruction::MSIZE) + return true; // msize is modified already by memory access, avoid that for now + if (_item.instruction() == Instruction::SHA3) + return true; //@todo: we have to compare sha3's not based on their memory addresses but on the memory content. + InstructionInfo info = instructionInfo(_item.instruction()); + if (_item.instruction() == Instruction::SSTORE) + return false; + if (_item.instruction() == Instruction::MSTORE) + return false; + //@todo: We do not handle the following memory instructions for now: + // calldatacopy, codecopy, extcodecopy, mstore8, + // msize (note that msize also depends on memory read access) + + // the second requirement will be lifted once it is implemented + return info.sideEffects || info.args > 2; + } + } +} + +bool SemanticInformation::isCommutativeOperation(AssemblyItem const& _item) +{ + if (_item.type() != Operation) + return false; + switch (_item.instruction()) + { + case Instruction::ADD: + case Instruction::MUL: + case Instruction::EQ: + case Instruction::AND: + case Instruction::OR: + case Instruction::XOR: + return true; + default: + return false; + } +} + +bool SemanticInformation::isDupInstruction(AssemblyItem const& _item) +{ + if (_item.type() != Operation) + return false; + return Instruction::DUP1 <= _item.instruction() && _item.instruction() <= Instruction::DUP16; +} + +bool SemanticInformation::isSwapInstruction(AssemblyItem const& _item) +{ + if (_item.type() != Operation) + return false; + return Instruction::SWAP1 <= _item.instruction() && _item.instruction() <= Instruction::SWAP16; +} + +bool SemanticInformation::isJumpInstruction(AssemblyItem const& _item) +{ + return _item == AssemblyItem(Instruction::JUMP) || _item == AssemblyItem(Instruction::JUMPI); +} diff --git a/libevmcore/SemanticInformation.h b/libevmcore/SemanticInformation.h new file mode 100644 index 000000000..7497dc651 --- /dev/null +++ b/libevmcore/SemanticInformation.h @@ -0,0 +1,50 @@ +/* + This file is part of cpp-ethereum. + + cpp-ethereum 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. + + cpp-ethereum 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 cpp-ethereum. If not, see . +*/ +/** + * @file SemanticInformation.h + * @author Christian + * @date 2015 + * Helper to provide semantic information about assembly items. + */ + +#pragma once + + +namespace dev +{ +namespace eth +{ + +class AssemblyItem; + +/** + * Helper functions to provide context-independent information about assembly items. + */ +struct SemanticInformation +{ + /// @returns true if the given items starts a new block for common subexpression analysis. + static bool breaksCSEAnalysisBlock(AssemblyItem const& _item); + /// @returns true if the item is a two-argument operation whose value does not depend on the + /// order of its arguments. + static bool isCommutativeOperation(AssemblyItem const& _item); + static bool isDupInstruction(AssemblyItem const& _item); + static bool isSwapInstruction(AssemblyItem const& _item); + static bool isJumpInstruction(AssemblyItem const& _item); +}; + +} +}