SystemVerilog OOP questions – interview or otherwise

As Indian VLSI industry is hiring at crazy rate for verification, SystemVerilog has emerged as a key differentiator in most of the front-end Verification job roles (see: http://www.linkedin.com/groups?homeNewMember=&gid=3706843). With many engineers adding SV skills to their CVs – the interviewers are getting tougher and smarter in their questions during interviews. Some related to OOP are below, source: http://verificationguild.com/modules.php?name=Forums&file=viewtopic&t=4410

As our CEO posted some code snippet to start with  -we thought we will assist our junior engineers to ponder around the same and explore more on this topic.

class base_pkt;
  bit b1;
  virtual function void display;
    $display ("base_pkt: b1: %b", this.b1);
  endfunction : display
endclass : base_pkt
class extended_pkt extends base_pkt;
  bit b2;
  virtual function void display;
    $display ("extended_pkt: b1: %b b2: %b", this.b1, this.b2);
  endfunction : display
  virtual function void ext_fn;
    $display ("EXT Function");
  endfunction : ext_fn
endclass : extended_pkt
class container_c;
  base_pkt b_p_0;
  function new;
    this.b_p_0 = new;
  endfunction : new
endclass : container_c
program test;
  container_c c_0;
  extended_pkt e_p_0;
  initial begin : b1
    c_0 = new;
    e_p_0 = new;
    c_0.b_p_0.display;
    c_0.b_p_0 = e_p_0;
    c_0.b_p_0.display;
    $finish;
  end : b1
endprogram : test

Some of the advanced questions from http://verificationguild.com/modules.php?name=Forums&file=viewtopic&t=4410

• can main access the methods and properties in the base_packet
• can main access the new methods and properties in the extended_packet class as it is or any casting would be needed
• assume one of the method in base_packet has a method that is virtual, what would happen if this method was called in the main method using the base class handle

Now – it is your turn to solve them based on above code starting point and ask more here in comments. We will try and help you with answers if you need!

 

Good Luck

TeamCVC

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