Method zeroValueFunction

libsolidity/codegen/YulUtilFunctions.cpp:4300–4373

}

std::string YulUtilFunctions::zeroValueFunction(Type const& _type, bool _splitFunctionTypes)
{
	solAssert(_type.category() != Type::Category::Mapping, "");

	std::string const functionName = "zero_value_for_" + std::string(_splitFunctionTypes ? "split_" : "") + _type.identifier();

	return m_functionCollector.createFunction(functionName, [&]() {
		FunctionType const* fType = dynamic_cast<FunctionType const*>(&_type);
		if (fType && fType->kind() == FunctionType::Kind::External && _splitFunctionTypes)
			return Whiskers(R"(
				function <functionName>() -> retAddress, retFunction {
					retAddress := 0
					retFunction := 0
				}
			)")
			("functionName", functionName)
			.render();

		if (_type.dataStoredIn(DataLocation::CallData))
		{
			solAssert(
				_type.category() == Type::Category::Struct ||
				_type.category() == Type::Category::Array,
			"");
			Whiskers templ(R"(
				function <functionName>() -> offset<?hasLength>, length</hasLength> {
					offset := calldatasize()
					<?hasLength> length := 0 </hasLength>
				}
			)");
			templ("functionName", functionName);
			templ("hasLength",
				_type.category() == Type::Category::Array &&
				dynamic_cast<ArrayType const&>(_type).isDynamicallySized()
			);

			return templ.render();
		}

		Whiskers templ(R"(
			function <functionName>() -> ret {
				ret := <zeroValue>
			}
		)");
		templ("functionName", functionName);

		if (_type.isValueType())
		{
			solAssert((
				_type.hasSimpleZeroValueInMemory() ||
				(fType && (fType->kind() == FunctionType::Kind::Internal || fType->kind() == FunctionType::Kind::External))
			), "");
			templ("zeroValue", "0");
		}
		else
		{
			solAssert(_type.dataStoredIn(DataLocation::Memory), "");
			if (auto const* arrayType = dynamic_cast<ArrayType const*>(&_type))