Sequence-Related Macros

`uvm_create(SEQ_OR_ITEM)

This action creates the item or sequence using the factory.  It intentionally does zero processing.  After this action completes, the user can manually set values, manipulate rand_mode and constraint_mode, etc.

`uvm_do(SEQ_OR_ITEM)

This macro takes as an argument a uvm_sequence_item variable or object.  The argument is created using `uvm_create if necessary, then randomized.  In the case of an item, it is randomized after the call to uvm_sequence_base::start_item() returns.  This is called late-randomization.  In the case of a sequence, the sub-sequence is started using uvm_sequence_base::start() with call_pre_post set to 0.  In the case of an item, the item is sent to the driver through the associated sequencer.

For a sequence item, the following are called, in order

`uvm_create(item)
sequencer.wait_for_grant(prior) (task)
this.pre_do(1)                  (task)
item.randomize()
this.mid_do(item)               (func)
sequencer.send_request(item)    (func)
sequencer.wait_for_item_done()  (task)
this.post_do(item)              (func)

For a sequence, the following are called, in order

`uvm_create(sub_seq)
sub_seq.randomize()
sub_seq.pre_start()         (task)
this.pre_do(0)              (task)
this.mid_do(sub_seq)        (func)
sub_seq.body()              (task)
this.post_do(sub_seq)       (func)
sub_seq.post_start()        (task)

`uvm_do_pri(SEQ_OR_ITEM, PRIORITY)

This is the same as `uvm_do except that the sequence item or sequence is executed with the priority specified in the argument

`uvm_do_with(SEQ_OR_ITEM, CONSTRAINTS)

This is the same as `uvm_do except that the constraint block in the 2nd argument is applied to the item or sequence in a randomize with statement before execution.

`uvm_do_pri_with(SEQ_OR_ITEM, PRIORITY, CONSTRAINTS)

This is the same as `uvm_do_pri except that the given constraint block is applied to the item or sequence in a randomize with statement before execution.

`uvm_create_on(SEQ_OR_ITEM, SEQR)

This is the same as `uvm_create except that it also sets the parent sequence to the sequence in which the macro is invoked, and it sets the sequencer to the specified SEQR argument.

`uvm_do_on(SEQ_OR_ITEM, SEQR)

This is the same as `uvm_do except that it also sets the parent sequence to the sequence in which the macro is invoked, and it sets the sequencer to the specified SEQR argument.

`uvm_do_on_pri(SEQ_OR_ITEM, SEQR, PRIORITY)

This is the same as `uvm_do_pri except that it also sets the parent sequence to the sequence in which the macro is invoked, and it sets the sequencer to the specified SEQR argument.

`uvm_do_on_with(SEQ_OR_ITEM, SEQR, CONSTRAINTS)

This is the same as `uvm_do_with except that it also sets the parent sequence to the sequence in which the macro is invoked, and it sets the sequencer to the specified SEQR argument.  The user must supply brackets around the constraints.

`uvm_do_on_pri_with(SEQ_OR_ITEM, SEQR, PRIORITY, CONSTRAINTS)

This is the same as `uvm_do_pri_with except that it also sets the parent sequence to the sequence in which the macro is invoked, and it sets the sequencer to the specified SEQR argument.

`uvm_send(SEQ_OR_ITEM)

This macro processes the item or sequence that has been created using `uvm_create.  The processing is done without randomization.  Essentially, an `uvm_do without the create or randomization.

`uvm_send_pri(SEQ_OR_ITEM, PRIORITY)

This is the same as `uvm_send except that the sequence item or sequence is executed with the priority specified in the argument.

`uvm_rand_send(SEQ_OR_ITEM)

This macro processes the item or sequence that has been already been allocated (possibly with `uvm_create).  The processing is done with randomization.  Essentially, an `uvm_do without the create.

`uvm_rand_send_pri(SEQ_OR_ITEM, PRIORITY)

This is the same as `uvm_rand_send except that the sequence item or sequence is executed with the priority specified in the argument.

`uvm_rand_send_with(SEQ_OR_ITEM, CONSTRAINTS)

This is the same as `uvm_rand_send except that the given constraint block is applied to the item or sequence in a randomize with statement before execution.

`uvm_rand_send_pri_with(SEQ_OR_ITEM, PRIORITY, CONSTRAINTS)

This is the same as `uvm_rand_send_pri except that the given constraint block is applied to the item or sequence in a randomize with statement before execution.

Adds the given sequence TYPE to the given sequence library LIBTYPE

`uvm_add_to_seq_lib(TYPE,LIBTYPE)

Invoke any number of times within a sequence declaration to statically add that sequence to one or more sequence library types.  The sequence will then be available for selection and execution in all instances of the given sequencer types.

class seqA extends uvm_sequence_base #(simple_item);

   function new(string name=`"TYPE`");
     super.new(name);
   endfunction

   `uvm_object_utils(seqA)

   `uvm_add_to_seq_lib(seqA, simple_seq_lib_RST)
   `uvm_add_to_seq_lib(seqA, simple_seq_lib_CFG)

   virtual task body(); \
     `uvm_info("SEQ_START", {"Executing sequence '", get_full_name(),
                            "' (",get_type_name(),")"},UVM_HIGH)
     #10;
   endtask

 endclass

`uvm_sequence_library_utils(TYPE)

Declares the infrastructure needed to define extensions to the uvm_sequence_library class.  You define new sequence library subtypes to statically specify sequence membership from within sequence definitions.  See also `uvm_add_to_sequence_library for more information.

typedef simple_seq_lib uvm_sequence_library #(simple_item);

class simple_seq_lib_RST extends simple_seq_lib;

  `uvm_object_utils(simple_seq_lib_RST)

  `uvm_sequence_library_utils(simple_seq_lib_RST)

  function new(string name="");
    super.new(name);
  endfunction

endclass

Each library, itself a sequence, can then be started independently on different sequencers or in different phases of the same sequencer.  See uvm_sequencer_base::start_phase_sequence for information on starting default sequences.

This macro is used to declare a variable p_sequencer whose type is specified by SEQUENCER.

`uvm_declare_p_sequencer(SEQUENCER)

The example below shows using the `uvm_declare_p_sequencer macro along with the uvm_object_utils macros to set up the sequence but not register the sequence in the sequencer’s library.

class mysequence extends uvm_sequence#(mydata);
  `uvm_object_utils(mysequence)
  `uvm_declare_p_sequencer(some_seqr_type)
  task body;
    //Access some variable in the user's custom sequencer
    if(p_sequencer.some_variable) begin
      ...
    end
  endtask
endclass