4 files changed, 41 insertions, 18 deletions

diff --git a/libsolidity/codegen/CompilerUtils.cpp b/libsolidity/codegen/CompilerUtils.cpp
index ce97ed61..f9b181ae 100644
--- a/libsolidity/codegen/CompilerUtils.cpp
+++ b/libsolidity/codegen/CompilerUtils.cpp
@@ -191,7 +191,7 @@ void CompilerUtils::encodeToMemory(
 	{
 		// Use the new JULIA-based encoding function
 		auto stackHeightBefore = m_context.stackHeight();
-		abiEncode(_givenTypes, targetTypes, _encodeAsLibraryTypes);
+		abiEncodeV2(_givenTypes, targetTypes, _encodeAsLibraryTypes);
 		solAssert(stackHeightBefore - m_context.stackHeight() == sizeOnStack(_givenTypes), "");
 		return;
 	}
@@ -302,7 +302,7 @@ void CompilerUtils::encodeToMemory(
 	popStackSlots(argSize + dynPointers + 1);
 }
 
-void CompilerUtils::abiEncode(
+void CompilerUtils::abiEncodeV2(
 	TypePointers const& _givenTypes,
 	TypePointers const& _targetTypes,
 	bool _encodeAsLibraryTypes
diff --git a/libsolidity/codegen/CompilerUtils.h b/libsolidity/codegen/CompilerUtils.h
index b239bde6..ad3989ad 100644
--- a/libsolidity/codegen/CompilerUtils.h
+++ b/libsolidity/codegen/CompilerUtils.h
@@ -109,6 +109,19 @@ public:
 		bool _encodeAsLibraryTypes = false
 	);
 
+	/// Special case of @a encodeToMemory which assumes tight packing, e.g. no zero padding
+	/// and dynamic data is encoded in-place.
+	/// Stack pre: <value0> <value1> ... <valueN-1> <head_start>
+	/// Stack post: <mem_ptr>
+	void packedEncode(
+		TypePointers const& _givenTypes,
+		TypePointers const& _targetTypes,
+		bool _encodeAsLibraryTypes = false
+	)
+	{
+		encodeToMemory(_givenTypes, _targetTypes, false, true, _encodeAsLibraryTypes);
+	}
+
 	/// 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).
 	/// Stack pre: <value0> <value1> ... <valueN-1> <head_start>
@@ -117,6 +130,20 @@ public:
 		TypePointers const& _givenTypes,
 		TypePointers const& _targetTypes,
 		bool _encodeAsLibraryTypes = false
+	)
+	{
+		encodeToMemory(_givenTypes, _targetTypes, true, false, _encodeAsLibraryTypes);
+	}
+
+	/// 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).
+	/// Uses a new, less tested encoder implementation.
+	/// Stack pre: <value0> <value1> ... <valueN-1> <head_start>
+	/// Stack post: <mem_ptr>
+	void abiEncodeV2(
+		TypePointers const& _givenTypes,
+		TypePointers const& _targetTypes,
+		bool _encodeAsLibraryTypes = false
 	);
 
 	/// Zero-initialises (the data part of) an already allocated memory array.
diff --git a/libsolidity/codegen/ContractCompiler.cpp b/libsolidity/codegen/ContractCompiler.cpp
index 92782b8d..429db532 100644
--- a/libsolidity/codegen/ContractCompiler.cpp
+++ b/libsolidity/codegen/ContractCompiler.cpp
@@ -421,7 +421,7 @@ void ContractCompiler::appendReturnValuePacker(TypePointers const& _typeParamete
 		utils.fetchFreeMemoryPointer();
 		//@todo optimization: if we return a single memory array, there should be enough space before
 		// its data to add the needed parts and we avoid a memory copy.
-		utils.encodeToMemory(_typeParameters, _typeParameters, true, false, _isLibrary);
+		utils.abiEncode(_typeParameters, _typeParameters, _isLibrary);
 		utils.toSizeAfterFreeMemoryPointer();
 		m_context << Instruction::RETURN;
 	}
diff --git a/libsolidity/codegen/ExpressionCompiler.cpp b/libsolidity/codegen/ExpressionCompiler.cpp
index 5de24136..c2bf0f5c 100644
--- a/libsolidity/codegen/ExpressionCompiler.cpp
+++ b/libsolidity/codegen/ExpressionCompiler.cpp
@@ -581,7 +581,7 @@ bool ExpressionCompiler::visit(FunctionCall const& _functionCall)
 					_context << Instruction::ADD;
 				}
 			);
-			utils().encodeToMemory(argumentTypes, function.parameterTypes(), true, false);
+			utils().abiEncode(argumentTypes, function.parameterTypes());
 			// now on stack: memory_end_ptr
 			// need: size, offset, endowment
 			utils().toSizeAfterFreeMemoryPointer();
@@ -675,7 +675,8 @@ bool ExpressionCompiler::visit(FunctionCall const& _functionCall)
 				argumentTypes.push_back(arg->annotation().type);
 			}
 			utils().fetchFreeMemoryPointer();
-			utils().encodeToMemory(argumentTypes, TypePointers(), function.padArguments(), true);
+			solAssert(!function.padArguments(), "");
+			utils().packedEncode(argumentTypes, TypePointers());
 			utils().toSizeAfterFreeMemoryPointer();
 			m_context << Instruction::KECCAK256;
 			break;
@@ -694,11 +695,10 @@ bool ExpressionCompiler::visit(FunctionCall const& _functionCall)
 			}
 			arguments.front()->accept(*this);
 			utils().fetchFreeMemoryPointer();
-			utils().encodeToMemory(
+			utils().packedEncode(
 				{arguments.front()->annotation().type},
-				{function.parameterTypes().front()},
-				false,
-				true);
+				{function.parameterTypes().front()}
+			);
 			utils().toSizeAfterFreeMemoryPointer();
 			m_context << logInstruction(logNumber);
 			break;
@@ -717,11 +717,9 @@ bool ExpressionCompiler::visit(FunctionCall const& _functionCall)
 					if (auto const& arrayType = dynamic_pointer_cast<ArrayType const>(function.parameterTypes()[arg - 1]))
 					{
 						utils().fetchFreeMemoryPointer();
-						utils().encodeToMemory(
+						utils().packedEncode(
 							{arguments[arg - 1]->annotation().type},
-							{arrayType},
-							false,
-							true
+							{arrayType}
 						);
 						utils().toSizeAfterFreeMemoryPointer();
 						m_context << Instruction::KECCAK256;
@@ -751,7 +749,7 @@ bool ExpressionCompiler::visit(FunctionCall const& _functionCall)
 					nonIndexedParamTypes.push_back(function.parameterTypes()[arg]);
 				}
 			utils().fetchFreeMemoryPointer();
-			utils().encodeToMemory(nonIndexedArgTypes, nonIndexedParamTypes, true, false);
+			utils().abiEncode(nonIndexedArgTypes, nonIndexedParamTypes);
 			// need: topic1 ... topicn memsize memstart
 			utils().toSizeAfterFreeMemoryPointer();
 			m_context << logInstruction(numIndexed);
@@ -1212,11 +1210,9 @@ bool ExpressionCompiler::visit(IndexAccess const& _indexAccess)
 			utils().fetchFreeMemoryPointer();
 			// stack: base index mem
 			// note: the following operations must not allocate memory!
-			utils().encodeToMemory(
+			utils().packedEncode(
 				TypePointers{_indexAccess.indexExpression()->annotation().type},
-				TypePointers{keyType},
-				false,
-				true
+				TypePointers{keyType}
 			);
 			m_context << Instruction::SWAP1;
 			utils().storeInMemoryDynamic(IntegerType(256));