Parameterized Component registered via `uvm_component_utils Macro

UVM
,
1

Out of curiosity I was trying an example of running a parameterized test ( registered via `uvm_component_utils macro ) .



  `include "uvm_macros.svh"
  `include "uvm_pkg.sv"
   
   import uvm_pkg::* ;

  `define COMP function new( string name , uvm_component parent );\
                   super.new(name,parent);\
               endfunction

  class  test #( BITWIDTH = 128 )  extends  uvm_test ;
  
      `uvm_component_utils( test #(BITWIDTH)  )    //  What  would  be  String  Registration  ??
  
      `COMP 
   
   function void build_phase ( uvm_phase phase ) ;
       
     `uvm_info(get_name(),$sformatf(" In  build_phase  of  test#( %0d ) ", BITWIDTH ) , UVM_NONE)  
     
   endfunction
   
  endclass


  module  top_tb ;    
  
   test #( 256 ) test_256 ;  //  [A]  Specialization  Needed  since  Parameterized  Class  !!
  
    initial begin

       run_test("test#(256)");   //   Issue  with  this !!

    end
  
 endmodule

I Observe Output ::

UVM_WARNING @ 0: reporter [BDTYP] Cannot create a component of type ‘test #(256)’ because it is not registered with the factory.
UVM_FATAL @ 0: reporter [INVTST] Requested test from call to run_test(test#(256)) not found.

However if I change the string argument to run_test() to ::


 run_test("test#(BITWIDTH)");  //  This  works  !!

I understand that String Registration occus via Text Substitution macro ( "" ) internally .
So shouldn’t the actual value ( 256 ) be used instead of parameter name??

One possibility I see is that macro `uvm_component_utils gets expanded at Compile time whereas the specialization occurs at elaboration time .

2

In reply to dave_59:

Thanks for the reply .
I understand that multiple specialization in above example would be incorrect .
But in case of multiple specialization there is a UVM_WARNING from the library rather than an UVM_ERROR .



module  top_tb ;    
 
 test #( 256 ) test_256 ;  //  [A]  Specialization  Needed  since  Parameterized  Class  !!
    
 test #( 200 ) test_200 ;  //  2nd  Specialization
 
    initial begin
 
       run_test("test#(256)");   //   Issue  with  this !!
 
    end
 
 endmodule

I Observe ::

UVM_WARNING @ 0: reporter [TPRGED] Type name ‘test #(BITWIDTH)’ already registered with factory. No string-based lookup support for multiple types with the same type name.
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