Hi ALL, Can anybody tell me the exact application of the clone methos? What is the significance of the clone method? Regards, Ankit.

The clone method is used to provide a deep (nested) copy of an object. clone first allocates new memory for the object, then copies over each field to the new object. If a field is an object handle, then instead of copying the handle (which would do a “shallow” copy) you would call fieldname.clone…

clone() returns a handle of newly created object which is copy of original object. If you want to use copy(), New objected has to be created explicitly. Look at page number 267, 284 of AVM cook book.

Hi Ankit, you can simply remember as clone = create and (+) copy That is, it first creates a new object and then copies all the data to the newly created object. Regards, Moneesh

Another key difference is that **clone()**is virtual;**copy()**is non-virtual. And clone() is a method of the original object; copy() is a method of the target object. That means clone() creates a copy an object of the same class type as the original. With copy(), the original object could be a sub…

In reply to dave_59 : Hi Dave, With copy(), the original object could be a subclass of the target object's type with additional class properties that will not get copied. I haven’t understood why “additional class properties will not get copied” for copy() as the subclass (child) is inherited from…

In reply to mseyunni : class base; int p1; function void copy(base orig); this.p1 = orig.p1; endfunction endclass class ex_base; int p2; function void copy(base orig); super.copy(b); this.p2 = orig.p2; endfunction endclass base b1,b2; ex_base eb1, eb2; initial begin eb1 = n…

In reply to dave_59 : p2 will copy if we write b1.copy(eb2)?

I do not understand the claims about copy() here. I agree with the example code, but in UVM the non-virtual copy() method calls the virtual do_copy() method. So the do_copy of the derived class gets called, and hence its members do get copied? For example: class base extends uvm_object; `uvm_…

In reply to dave_59 : Hi Dave, I can understand which you gave the example of copy but i need the example for clone() also.You said copy() is virtual in that thing i just confused what is virtual will you please clear my doudt i am new learner of SV. thanks in advance.

In reply to NiLu : The OVM and UVM mechanisms are the same. The OVM added the virtual do_copy() methods as a hook to the non-virtual copy() methods. This might be to get their field automation macros to work. In reply to swethasundararaj : class base; int p1; function void copy(base orig); th…

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Importance of the clone( ) method

OVM

svq January 5, 2020, 7:13pm 17

In reply to dave_59:

Thanks Dave for the explanation. Makes sense now