Post_randomization block is not executing

UVM
,
1

Hay!
I have used a post_randomize function in my sequence_item class.
Also I have used for loop, while loop, if statements inside it
i am using .randomize() inside a task in sequence class.
when i am running the post_randomize() function is not executing.
plz help me out this.

2

In reply to jd_jagdish:

Could you please show your sequence body task and the definition of the seq_item.

3

In reply to jd_jagdish:

Did you check the return value from the call to randomize()? post_randomize() does not get called if the solver fails.

4

In reply to chr_sue:

This is my code

//sequence_item class 

class packet extends uvm_sequence_item;

//input signal that can be randomize
rand 	bit start_1;
rand 	bit ble;
rand 	bit cca;

// output logic signal that should not be randomize
logic result;

`uvm_object_utils_begin(packet)
	`uvm_field_int(start_1,UVM_ALL_ON|UVM_DEC)
	`uvm_field_int(ble,UVM_ALL_ON|UVM_DEC)
	`uvm_field_int(cca,UVM_ALL_ON|UVM_DEC)
`uvm_object_utils_end



int cnt=0;
bit count=0;
constraint valid{
	
	//start inside {[0:1]};
		cca inside {[0:1]};
		ble inside {[0:1]};
}

function void post_randomization();

while(cnt<4)
	begin
		if (count==1)
			begin	
				start_1=1;
				cca=0;
				ble=0;
				count=~count;
			end
		else
			begin
				start_1=0;
				cca=0;
				ble=0;
				count=~count;		
			end
	cnt=cnt+1;
	end
if(cnt==4)
	begin
		count=1;
		cnt=cnt+1;
	end
else if(cnt>4)

			begin
				cca=1;
				ble=1;
				
			end
			
		else
			begin
				cca=1;
				ble=0;
			end
	end
		
endfunction

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

endclass:packet


//sequence class

class packet_sequence extends uvm_sequence#(packet);
	`uvm_object_utils(packet_sequence)
	
	bit start_1;
	bit ble;
	bit cca;

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

task body();
	
	packet ref_pkt;
	ref_pkt=packet::type_id::create("ref_pkt");
	repeat(50)
	begin
	`uvm_create(req)
		assert(ref_pkt.randomize with {ref_pkt.start_1==0;ref_pkt.ble==0;ref_pkt.cca==0;});
		
		req.copy(ref_pkt);
		start_1=req.start_1;
		cca=req.cca;
		ble=req.ble;
		start_item(req);
		req.print(uvm_default_line_printer);
		finish_item(req);
		
	
	`uvm_create(req)
		assert(ref_pkt.randomize with {ref_pkt.start_1==1;ref_pkt.ble==0;ref_pkt.cca==1;});
		req.copy(ref_pkt);
		start_1=req.start_1;
		cca=req.cca;
		ble=req.ble;
		start_item(req);
		req.print(uvm_default_line_printer);
		finish_item(req);
		
		end	
endtask		
endclass:packet_sequence
5

In reply to dave_59:

should i need to use return after .randomize() in body of sequence class?

6

In reply to jd_jagdish:

2 things:
(1) do you see the diagnostic messages (print) in your log-file?
(2) why you are using a copy (req) of your original data packet (ref_pkt)?

7

In reply to chr_sue:

yes i am getting the print messages in log file.
The “req” that i have used is not required. I simply used to check what’s happening.

8

In reply to jd_jagdish:

If you see the print messages from post_randomize it will be definitely executed.
I gues you are getting in the driver the ref_pkt instead of req.