Merge pull request #2704 from ethereum/newEncoder

New ABI encoder

libsolidity/ast/ExperimentalFeatures.h

@@ -29,15 +29,19 @@ namespace solidity
 
 enum class ExperimentalFeature
 {
+	ABIEncoderV2, // new ABI encoder that makes use of JULIA
 	Test,
 	TestOnlyAnalysis
 };
 
-static const std::map<ExperimentalFeature, bool> ExperimentalFeatureOnlyAnalysis = {
+static const std::map<ExperimentalFeature, bool> ExperimentalFeatureOnlyAnalysis =
+{
 	{ ExperimentalFeature::TestOnlyAnalysis, true },
 };
 
-static const std::map<std::string, ExperimentalFeature> ExperimentalFeatureNames = {
+static const std::map<std::string, ExperimentalFeature> ExperimentalFeatureNames =
+{
+	{ "ABIEncoderV2", ExperimentalFeature::ABIEncoderV2 },
 	{ "__test", ExperimentalFeature::Test },
 	{ "__testOnlyAnalysis", ExperimentalFeature::TestOnlyAnalysis },
 };

libsolidity/ast/Types.cpp

@@ -1529,8 +1529,6 @@ TypePointer ArrayType::interfaceType(bool _inLibrary) const
 	TypePointer baseExt = m_baseType->interfaceType(_inLibrary);
 	if (!baseExt)
 		return TypePointer();
-	if (m_baseType->category() == Category::Array && m_baseType->isDynamicallySized())
-		return TypePointer();
 
 	if (isDynamicallySized())
 		return make_shared<ArrayType>(DataLocation::Memory, baseExt);

libsolidity/codegen/ABIFunctions.h

@@ -0,0 +1,172 @@
+/*
+	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/>.
+*/
+/**
+ * @author Christian <chris@ethereum.org>
+ * @date 2017
+ * Routines that generate JULIA code related to ABI encoding, decoding and type conversions.
+ */
+
+#pragma once
+
+#include <libsolidity/ast/ASTForward.h>
+
+#include <vector>
+#include <functional>
+#include <map>
+
+namespace dev {
+namespace solidity {
+
+class Type;
+class ArrayType;
+class StructType;
+class FunctionType;
+using TypePointer = std::shared_ptr<Type const>;
+using TypePointers = std::vector<TypePointer>;
+
+///
+/// Class to generate encoding and decoding functions. Also maintains a collection
+/// of "functions to be generated" in order to avoid generating the same function
+/// multiple times.
+///
+/// Make sure to include the result of ``requestedFunctions()`` to a block that
+/// is visible from the code that was generated here.
+class ABIFunctions
+{
+public:
+	~ABIFunctions();
+
+	/// @returns assembly code block to ABI-encode values of @a _givenTypes residing on the stack
+	/// into memory, converting the types to @a _targetTypes on the fly.
+	/// Assumed variables to be present: <$value0> <$value1> ... <$value(n-1)> <$headStart>
+	/// Does not allocate memory (does not change the memory head pointer), but writes
+	/// to memory starting at $headStart and an unrestricted amount after that.
+	/// Assigns the end of encoded memory either to $value0 or (if that is not present)
+	/// to $headStart.
+	std::string tupleEncoder(
+		TypePointers const& _givenTypes,
+		TypePointers const& _targetTypes,
+		bool _encodeAsLibraryTypes = false
+	);
+
+	/// @returns auxiliary functions referenced from the block generated in @a tupleEncoder
+	std::string requestedFunctions();
+
+private:
+	/// @returns the name of the cleanup function for the given type and
+	/// adds its implementation to the requested functions.
+	/// @param _revertOnFailure if true, causes revert on invalid data,
+	/// otherwise an assertion failure.
+	std::string cleanupFunction(Type const& _type, bool _revertOnFailure = false);
+
+	/// @returns the name of the function that converts a value of type @a _from
+	/// to a value of type @a _to. The resulting vale is guaranteed to be in range
+	/// (i.e. "clean"). Asserts on failure.
+	std::string conversionFunction(Type const& _from, Type const& _to);
+
+	std::string cleanupCombinedExternalFunctionIdFunction();
+
+	/// @returns a function that combines the address and selector to a single value
+	/// for use in the ABI.
+	std::string combineExternalFunctionIdFunction();
+
+	/// @returns the name of the ABI encoding function with the given type
+	/// and queues the generation of the function to the requested functions.
+	/// @param _compacted if true, the input value was just loaded from storage
+	/// or memory and thus might be compacted into a single slot (depending on the type).
+	std::string abiEncodingFunction(
+		Type const& _givenType,
+		Type const& _targetType,
+		bool _encodeAsLibraryTypes,
+		bool _compacted
+	);
+	/// Part of @a abiEncodingFunction for array target type and given calldata array.
+	std::string abiEncodingFunctionCalldataArray(
+		Type const& _givenType,
+		Type const& _targetType,
+		bool _encodeAsLibraryTypes
+	);
+	/// Part of @a abiEncodingFunction for array target type and given memory array or
+	/// a given storage array with one item per slot.
+	std::string abiEncodingFunctionSimpleArray(
+		ArrayType const& _givenType,
+		ArrayType const& _targetType,
+		bool _encodeAsLibraryTypes
+	);
+	std::string abiEncodingFunctionMemoryByteArray(
+		ArrayType const& _givenType,
+		ArrayType const& _targetType,
+		bool _encodeAsLibraryTypes
+	);
+	/// Part of @a abiEncodingFunction for array target type and given storage array
+	/// where multiple items are packed into the same storage slot.
+	std::string abiEncodingFunctionCompactStorageArray(
+		ArrayType const& _givenType,
+		ArrayType const& _targetType,
+		bool _encodeAsLibraryTypes
+	);
+
+	// @returns the name of the ABI encoding function with the given type
+	// and queues the generation of the function to the requested functions.
+	// Case for _givenType being a string literal
+	std::string abiEncodingFunctionStringLiteral(
+		Type const& _givenType,
+		Type const& _targetType,
+		bool _encodeAsLibraryTypes
+	);
+
+	std::string abiEncodingFunctionFunctionType(
+		FunctionType const& _from,
+		Type const& _to,
+		bool _encodeAsLibraryTypes,
+		bool _compacted
+	);
+
+	/// @returns a function that copies raw bytes of dynamic length from calldata
+	/// or memory to memory.
+	/// Pads with zeros and might write more than exactly length.
+	std::string copyToMemoryFunction(bool _fromCalldata);
+
+	std::string shiftLeftFunction(size_t _numBits);
+	std::string shiftRightFunction(size_t _numBits, bool _signed);
+	/// @returns the name of a function that rounds its input to the next multiple
+	/// of 32 or the input if it is a multiple of 32.
+	std::string roundUpFunction();
+
+	std::string arrayLengthFunction(ArrayType const& _type);
+	/// @returns the name of a function that converts a storage slot number
+	/// or a memory pointer to the slot number / memory pointer for the data position of an array
+	/// which is stored in that slot / memory area.
+	std::string arrayDataAreaFunction(ArrayType const& _type);
+	/// @returns the name of a function that advances an array data pointer to the next element.
+	/// Only works for memory arrays and storage arrays that store one item per slot.
+	std::string nextArrayElementFunction(ArrayType const& _type);
+
+	/// Helper function that uses @a _creator to create a function and add it to
+	/// @a m_requestedFunctions if it has not been created yet and returns @a _name in both
+	/// cases.
+	std::string createFunction(std::string const& _name, std::function<std::string()> const& _creator);
+
+	/// @returns the size of the static part of the encoding of the given types.
+	size_t headSize(TypePointers const& _targetTypes);
+
+	/// Map from function name to code for a multi-use function.
+	std::map<std::string, std::string> m_requestedFunctions;
+};
+
+}
+}

libsolidity/codegen/CompilerContext.cpp

@@ -44,11 +44,6 @@ namespace dev
 namespace solidity
 {
 
-void CompilerContext::addMagicGlobal(MagicVariableDeclaration const& _declaration)
-{
-	m_magicGlobals.insert(&_declaration);
-}
-
 void CompilerContext::addStateVariable(
 	VariableDeclaration const& _declaration,
 	u256 const& _storageOffset,

libsolidity/codegen/CompilerContext.h

@@ -48,7 +48,7 @@ namespace solidity {
 class CompilerContext
 {
 public:
-	CompilerContext(CompilerContext* _runtimeContext = nullptr):
+	explicit CompilerContext(CompilerContext* _runtimeContext = nullptr):
 		m_asm(std::make_shared<eth::Assembly>()),
 		m_runtimeContext(_runtimeContext)
 	{
@@ -56,7 +56,9 @@ public:
 			m_runtimeSub = size_t(m_asm->newSub(m_runtimeContext->m_asm).data());
 	}
 
-	void addMagicGlobal(MagicVariableDeclaration const& _declaration);
+	void setExperimentalFeatures(std::set<ExperimentalFeature> const& _features) { m_experimentalFeatures = _features; }
+	bool experimentalFeatureActive(ExperimentalFeature _feature) const { return m_experimentalFeatures.count(_feature); }
+
 	void addStateVariable(VariableDeclaration const& _declaration, u256 const& _storageOffset, unsigned _byteOffset);
 	void addVariable(VariableDeclaration const& _declaration, unsigned _offsetToCurrent = 0);
 	void removeVariable(VariableDeclaration const& _declaration);
@@ -68,7 +70,6 @@ public:
 	void adjustStackOffset(int _adjustment) { m_asm->adjustDeposit(_adjustment); }
 	unsigned stackHeight() const { solAssert(m_asm->deposit() >= 0, ""); return unsigned(m_asm->deposit()); }
 
-	bool isMagicGlobal(Declaration const* _declaration) const { return m_magicGlobals.count(_declaration) != 0; }
 	bool isLocalVariable(Declaration const* _declaration) const;
 	bool isStateVariable(Declaration const* _declaration) const { return m_stateVariables.count(_declaration) != 0; }
 
@@ -265,8 +266,8 @@ private:
 	} m_functionCompilationQueue;
 
 	eth::AssemblyPointer m_asm;
-	/// Magic global variables like msg, tx or this, distinguished by type.
-	std::set<Declaration const*> m_magicGlobals;
+	/// Activated experimental features.
+	std::set<ExperimentalFeature> m_experimentalFeatures;
 	/// Other already compiled contracts to be used in contract creation calls.
 	std::map<ContractDefinition const*, eth::Assembly const*> m_compiledContracts;
 	/// Storage offsets of state variables

libsolidity/codegen/CompilerUtils.cpp

@@ -25,6 +25,7 @@
 #include <libevmasm/Instruction.h>
 #include <libsolidity/codegen/ArrayUtils.h>
 #include <libsolidity/codegen/LValue.h>
+#include <libsolidity/codegen/ABIFunctions.h>
 
 using namespace std;
 
@@ -182,6 +183,18 @@ void CompilerUtils::encodeToMemory(
 
 	if (_givenTypes.empty())
 		return;
+	else if (
+		_padToWordBoundaries &&
+		!_copyDynamicDataInPlace &&
+		m_context.experimentalFeatureActive(ExperimentalFeature::ABIEncoderV2)
+	)
+	{
+		// Use the new JULIA-based encoding function
+		auto stackHeightBefore = m_context.stackHeight();
+		abiEncode(_givenTypes, targetTypes, _encodeAsLibraryTypes);
+		solAssert(stackHeightBefore - m_context.stackHeight() == sizeOnStack(_givenTypes), "");
+		return;
+	}
 
 	// Stack during operation:
 	// <v1> <v2> ... <vn> <mem_start> <dyn_head_1> ... <dyn_head_r> <end_of_mem>
@@ -289,6 +302,28 @@ void CompilerUtils::encodeToMemory(
 	popStackSlots(argSize + dynPointers + 1);
 }
 
+void CompilerUtils::abiEncode(
+	TypePointers const& _givenTypes,
+	TypePointers const& _targetTypes,
+	bool _encodeAsLibraryTypes
+)
+{
+	// stack: <$value0> <$value1> ... <$value(n-1)> <$headStart>
+
+	vector<string> variables;
+	size_t numValues = sizeOnStack(_givenTypes);
+	for (size_t i = 0; i < numValues; ++i)
+			variables.push_back("$value" + to_string(i));
+	variables.push_back("$headStart");
+
+	ABIFunctions funs;
+	string routine = funs.tupleEncoder(_givenTypes, _targetTypes, _encodeAsLibraryTypes);
+	routine += funs.requestedFunctions();
+	m_context.appendInlineAssembly("{" + routine + "}", variables);
+	// Remove everyhing except for "value0" / the final memory pointer.
+	popStackSlots(numValues);
+}
+
 void CompilerUtils::zeroInitialiseMemoryArray(ArrayType const& _type)
 {
 	auto repeat = m_context.newTag();

libsolidity/codegen/CompilerUtils.h

@@ -103,6 +103,14 @@ public:
 		bool _encodeAsLibraryTypes = false
 	);
 
+	/// Special case of @a encodeToMemory which assumes that everything is padded to words
+	/// and dynamic data is not copied in place (i.e. a proper ABI encoding).
+	void abiEncode(
+		TypePointers const& _givenTypes,
+		TypePointers const& _targetTypes,
+		bool _encodeAsLibraryTypes = false
+	);
+
 	/// Zero-initialises (the data part of) an already allocated memory array.
 	/// Length has to be nonzero!
 	/// Stack pre: <length> <memptr>

libsolidity/codegen/ContractCompiler.cpp

@@ -100,6 +100,7 @@ void ContractCompiler::initializeContext(
 	map<ContractDefinition const*, eth::Assembly const*> const& _compiledContracts
 )
 {
+	m_context.setExperimentalFeatures(_contract.sourceUnit().annotation().experimentalFeatures);
 	m_context.setCompiledContracts(_compiledContracts);
 	m_context.setInheritanceHierarchy(_contract.annotation().linearizedBaseContracts);
 	CompilerUtils(m_context).initialiseFreeMemoryPointer();