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1.Sequence 中的 m_sequencer和p_sequencer ovm_sequencer_base继承而来在factory中注册的那个sequencer。区别是m_sequencer由ovm_sequencer_base保护，不可ovm_user来更改，而p_sequencer可由user通过`uvm_declare_p_sequencer(sequencer_name)来改变指向。 所以用户如果想从一个sequence得到sequencer的信息可指定p_sequencer的指向，之后通过p_sequencer.*的方式取得相应信息。 实例：（uvm实例ovm通用） `uvm_object_utils(seq_name)`uvm_declare_p_sequencer(sequencer_name)if you need to access the sequencer information (or any of its hierarchy information) from a sequence.I believe m_sequencer should not be used as it is protected. /forums/showthread.php?193-m_sequencer-vs-p_sequencer 2.一个Sequence 中的 CREATED： The sequence has been allocated. PRE_BODY： The sequence is started and the pre_body task is being executed. BODY： The sequence is started and the body task is being executed. POST_BODY：The sequence is started and the post_body task is being executed. ENDED： The sequence has ended by the completion of the body task. STOPPED： The sequence has been forcibly ended by issuing a kill() on the sequence. FINISHED： The sequence is completely finished executing. 3.OVM使仿真结束方法 （1）global_stop_request：基于task的目标结束方式 （2）ovm_test_done：object结束方式，当所有object dropped调用global_stop_request （3）kill or do_kill_all：强行结束，不推荐 （4）timeout：超时结束，需要用set_global_timeout来设定超时时间 详细内容参考OVM_Reference的P38 4.ovm_test_done ovm_test_done_objection的实例化class（global类），用来结束run phase。当所有它挂起的object都dropped时，其会调用global_stop_request来结束整个仿真 实例：ovm_example xbus/xbus_master_seq_lib.sv/xbus_base_sequence virtual class xbus_base_sequence extends ovm_sequence #(xbus_transfer); function new(string name=xbus_base_seq); super.new(name); endfunction // Raise in pre_body so the objection is only raised for root sequences. // There is no need to raise for sub-sequences since the root sequence // will encapsulate the sub-sequence. virtual task pre_body(); m_sequencer.ovm_report_info(get_type_name(), $psprintf(%s pre_body() raising an ovm_test_done objection, get_sequence_path()), OVM_M