Function dr_register_end_trace_event 

pub unsafe extern "C" fn dr_register_end_trace_event(
    func: Option<unsafe extern "C" fn(drcontext: *mut c_void, tag: *mut c_void, next_tag: *mut c_void) -> dr_custom_trace_action_t>,
)

Registers a callback function for the end-trace event. DR calls \p func before extending a trace with a new basic block. The \p func should return one of the #dr_custom_trace_action_t enum values.