Comparing types returned by get_type()

Question

I am trying to compare two types using the pattern

if(T1::get_type() != T2::get_type()) <do_something>

Questa fails this at runtime, calling it an illegal comparison. I wish I could use the type operator, but I also need to support VCS, and VCS does not support the type operator.

Also, T1 and T2 could be parameterized classes, specifically parameterized UVM components. Don't know if that matters.

Any help is greatly appreciated.

Answer 1

dave_59

Forum Moderator

10500 posts

February 03, 2015 at 3:58 pm

It's illegal because get_type() returns a handle to a proxy object of type uvm_component_registry#(T1,"T1") and uvm_component_registry#(T2,"T2"). You can't compare handles of different types.

What you really want is

if (type(T1) != type(T2) ) <do something>.Are you sure VCS does not support this? This has been in the LRM since 1800-2005

If you want to compare the types of two constructed UVM objects, you can use the virtual method get_object_type()
if ( t1_h.get_object_type() != t2_h.get_object_type() ) <do_something>;

— Dave Rich, Verification Architect, Siemens EDA

Answer 2

manning999

Full Access

31 posts

February 03, 2015 at 4:24 pm

In reply to dave_59:

Yes, that is what I really wanted, to use the type operator. VCS does not support it as recent as their 2014.12 release. I know it's been in the standard for a long time, and that's why it's very annoying.

The conditional is used to determine if something of a certain type should be constructed in the build phase, so I can't really use an instance-based method such as get_object_type().

Oh well.

Answer 3

dave_59

Forum Moderator

10500 posts

February 03, 2015 at 4:52 pm

In reply to manning999:

I believe this will work. Please include a comment that explains the proper way to code this

uvm_object_wrapper wrapt1,wrapt2;
      // because VCS does not support the constant expression: ( type(T1) != type(T2) )
      wrapt1 = T1::type_id::get();
      wrapt2 = T2::type_id::get();
      if (wrapt1 != wrapt2) <do_something>;

— Dave Rich, Verification Architect, Siemens EDA

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