'Create function with name and type signature'

def _create_function_base(self):

    global link_names, current_link_suffix
    default_link_name = 'jit_func'
    current_link_suffix += 1
    self.link_name = (default_link_name + str(current_link_suffix))
    link_names.add(self.link_name)
    fn_type = ll.FunctionType(self.llvm_ret_type, self.llvm_arg_types)
    self.fn = ll.Function(self.module, fn_type, name=self.link_name)
