'Assign default names to all variables.
:return: None'

def assign_variable_names(self):

    for var in self._variables:
        if isinstance(var, SimStackVariable):
            if (var.name is not None):
                continue
            if var.ident.startswith('iarg'):
                var.name = ('arg_%x' % var.offset)
            else:
                var.name = ('s_%x' % (- var.offset))
        elif isinstance(var, SimRegisterVariable):
            if (var.name is not None):
                continue
            var.name = var.ident
