Function instr_get_label_data_area 

pub unsafe extern "C" fn instr_get_label_data_area(
    instr: *mut instr_t,
) -> *mut dr_instr_label_data_t

\return a pointer to user-controlled data fields in a label instruction. These fields are available for use by clients for their own purposes. Returns NULL if \p instr is not a label instruction. \note These data fields are copied (shallowly) across instr_clone().