Global Handles in UVM

Mechanism in UVM-1.1

function void test_base::start_of_simulation_phase(uvm_phase phase);
	super.start_of_simulation_phase(phase);
	uvm_top.print_topology(); // Will not compile in UVM-1.2
	factory.print(); // Will not compile in UVM-1.2
endfunction

Global handles uvm_top and factory in uvm_pkg have been removed in UVM-1.2 and later

Mechanism in UVM-1.1 and UVM-1.2

Call the get() method of the class to retrieve the singleton handle.

function void test_base::start_of_simulation_phase(uvm_phase phase);
	super.start_of_simulation_phase(phase);
	uvm_root::get().print_topology(); // Works in UVM-1.1 & UVM-1.2
	uvm_factory::get().print(); // Works in UVM-1.1 & UVM-1.2
endfunction

Mechanism Only in UVM-1.2

function void test_base::start_of_simulation_phase(uvm_phase phase);
	uvm_coreservice_t cs = uvm_coreservice_t::get();
	cs.get_root().print_topology();
	cs.get_factory().print();
endfunction

uvm_coreservice_t is the uvm-1.2 mechanism for accessing all the central UVM services such as uvm_root,uvm_factory, uvm_report_server, etc.

// Using the uvm_coreservice_t:
uvm_coreservice_t cs;
uvm_factory f;
uvm_root top;
cs = uvm_coreservice_t::get();
f = cs.get_factory();
top = cs.get_root();