Merge pull request #1488 from chriseth/sol_optimizerRefactoring

Moved semantic information to its own file.

libevmcore/CommonSubexpressionEliminator.cpp

@@ -24,7 +24,7 @@
 #include <functional>
 #include <boost/range/adaptor/reversed.hpp>
 #include <libevmcore/CommonSubexpressionEliminator.h>
-#include <libevmcore/Assembly.h>
+#include <libevmcore/AssemblyItem.h>
 
 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<CSECodeGenerator::StoreOperation> const& _storeOperations

libevmcore/CommonSubexpressionEliminator.h

@@ -31,6 +31,7 @@
 #include <libdevcore/CommonIO.h>
 #include <libdevcore/Exceptions.h>
 #include <libevmcore/ExpressionClasses.h>
+#include <libevmcore/SemanticInformation.h>
 
 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++);

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 <http://www.gnu.org/licenses/>.
+*/
+/**
+ * @file SemanticInformation.cpp
+ * @author Christian <c@ethdev.com>
+ * @date 2015
+ * Helper to provide semantic information about assembly items.
+ */
+
+#include <libevmcore/SemanticInformation.h>
+#include <libevmcore/AssemblyItem.h>
+
+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);
+}

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 <http://www.gnu.org/licenses/>.
+*/
+/**
+ * @file SemanticInformation.h
+ * @author Christian <c@ethdev.com>
+ * @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);
+};
+
+}
+}