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  • when should we implement raise_objection(this) and drop_objection(this) in pre_body() and post_body() task respectively ?

when should we implement raise_objection(this) and drop_objection(this) in pre_body() and post_body() task respectively ?

UVM 6654
drop_objection in post... 2 raise_objection in pre... 3
Balu_15
Balu_15
Full Access
56 posts
December 17, 2013 at 10:32 pm

Hi,
i am trying to implement raise_objection() and drop_objection() in pre/post body. the simulator is giving fatal error message like "Null instance encountered when dereferencing 'this.starting phase'". Please suggest me how to implement and what is necessary ?

Example :

virtual task pre_body();
starting_phase.raise_objection(this);
endtask

virtual task post_body();
starting_phase.drop_objection(this);
endtask

Thanks
kbkdec15

Replies

Log In to Reply
basheer55
basheer55
Forum Access
30 posts
December 18, 2013 at 1:49 am

Hi,

I think you should use uvm_test_done.raise/drop_objection(this).

-Baser

Balu_15
Balu_15
Full Access
56 posts
December 18, 2013 at 10:56 pm

Hi Basheer,

Thanks for your responce.

why should use uvm_test_done.raise/drop_objection(this) or starting_phase.raise/drop_objection(this).

i am using raise/drop_objections at Test class.

Thanks
kbkdec15

Balu_15
Balu_15
Full Access
56 posts
December 18, 2013 at 11:06 pm

Hi Every One,

Please let me clear on this concept

Very advance Thanks

Regards
kbkdec15

Solution

Solution

cgales
cgales
Forum Moderator
1947 posts
December 19, 2013 at 9:38 am

It is highly recommended that raise_objection() and drop_objection() only be used in the run_phase() of your test. Since the run_phase() of your test will encapsulate all of your test sequences, there is no need to use raise_objection() or drop_objection() in any part of a sequence.

VE
VE
Full Access
112 posts
December 19, 2013 at 10:25 am

Hi Kbkdec :
Can you try to use raise_objection/drop_objection inside your seq body()? like
......
task body;
virtual task pre_start(); // optional
if ( starting_phase ! = null ) // to mk sure your seq is not sub_seq of another seq
staring_phase.raise_objection(this);
...
endtask
....
virtual task post_start(); // optional
if (starting_phase ! = null)
starting_address.drop_objection(this);
....
end
endtask

Balu_15
Balu_15
Full Access
56 posts
December 26, 2013 at 2:15 am

In reply to aming:

Hi Aming,

thanks for replay.

tool giving following error

Unresolved reference to 'staring_phase' in $root.staring_phase.raise_objection.

Thanks
kbkdec15

VE
VE
Full Access
112 posts
January 03, 2014 at 1:03 pm

I am sorry, There is a typo there. Would you try starting_phase instead of staring_phase?

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