Post_randomization block is not executing

UVM
,
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