Can We Pass Multiple Testnames To Uvm_testname

8 min read Oct 03, 2024

Can We Pass Multiple Testnames to `uvm_testname`?

The uvm_testname function in UVM (Universal Verification Methodology) is a powerful tool for setting the name of the current test being run. But you might wonder, "Can we pass multiple test names to uvm_testname?" The answer is no, you cannot directly pass multiple test names to the uvm_testname function.

Let's delve into why and explore some alternative approaches to achieve the desired result of specifying multiple test names.

Understanding `uvm_testname`

The uvm_testname function in UVM is designed to set a single, descriptive name for the currently executing test. This name is valuable for several reasons:

Test Reporting: The test name is used in various UVM reporting mechanisms, including the test report generated at the end of the simulation. This allows you to clearly identify which test was run.
Test Identification: During test execution, the test name helps distinguish between different tests, making it easier to understand the test environment's state and progress.
Test Filtering: Some UVM tools and frameworks leverage the test name for filtering tests, enabling the selection and execution of specific tests.

Why Multiple Test Names Aren't Supported

The uvm_testname function is designed to work with a single, string-based test name. This design ensures consistency and avoids ambiguities in test identification and reporting. The UVM framework expects a singular name for each test, making it difficult to accommodate multiple names within the function's structure.

Workarounds for Multiple Test Names

While you can't directly pass multiple names to uvm_testname, here are some workarounds to achieve a similar effect:

1. String Concatenation:

You can combine multiple test names into a single string using string concatenation operators.

string test_name = "test_a" + "_" + "test_b"; 
uvm_testname(test_name);

This approach creates a single string containing both test names, separated by an underscore. However, this might lead to lengthy test names and might not be ideal if you have many test names to concatenate.

2. UVM Macros and Parameters:

UVM provides mechanisms for defining macros and parameters. You can define a macro or parameter that holds a string containing multiple test names.

`define TEST_NAMES "test_a_test_b"

// or 
parameter string TEST_NAMES = "test_c_test_d";

uvm_testname(`TEST_NAMES); // Or uvm_testname(TEST_NAMES);

This approach helps organize your test names and allows for flexibility in updating them. However, you might need to modify the code whenever the test names change.

3. UVM Environment and Test Configuration:

UVM encourages using a dedicated environment class to manage test configuration. You can leverage the environment class to store and access multiple test names.

class my_env extends uvm_env;
 string test_name1;
 string test_name2;

 function new(string name = "my_env");
    super.new(name);
 endfunction

 function void build_phase(uvm_phase phase);
    test_name1 = "test_a";
    test_name2 = "test_b"; 
    uvm_testname(test_name1 + "_" + test_name2);
 endfunction
endclass

// In your test:
my_env env;
initial begin
 env = my_env::type_id::create("env");
 run_test(); 
end

This approach encapsulates the test name management within the environment, making it easier to maintain and modify. The test names are stored as separate variables, offering flexibility and control.

4. UVM Configuration Database:

UVM provides a powerful configuration database to store and retrieve various settings, including test names.

// In your test:
uvm_config_db#(string)::set(null, this, "TEST_NAME_1", "test_a");
uvm_config_db#(string)::set(null, this, "TEST_NAME_2", "test_b");

string test_name1;
string test_name2;

uvm_config_db#(string)::get(null, this, "TEST_NAME_1", test_name1);
uvm_config_db#(string)::get(null, this, "TEST_NAME_2", test_name2);

uvm_testname(test_name1 + "_" + test_name2);

This approach centralizes the test names within the UVM configuration database, making it easier to manage and update them across multiple tests.

5. Using Multiple Test Cases:

You can create multiple test cases, each with its unique test name, and execute them sequentially. This approach allows for clear separation of test names and execution.

// Test Case 1
class test_a extends uvm_test;
   function new(string name = "test_a");
      super.new(name);
   endfunction
endclass

// Test Case 2
class test_b extends uvm_test;
   function new(string name = "test_b");
      super.new(name);
   endfunction
endclass 

// In your testbench:
initial begin
   test_a test_case_a = new("test_a");
   test_case_a.run();

   test_b test_case_b = new("test_b");
   test_case_b.run();
end

This approach offers a structured way to organize tests and assign unique names to each.

Choose the Right Approach

The best workaround depends on your specific needs and how you organize your tests. Consider factors like:

Number of Test Names: If you have a few test names, string concatenation might be sufficient.
Test Name Management: If you need flexibility and centralized control over test names, UVM macros, parameters, or the configuration database are more suitable.
Test Organization: Using multiple test cases offers a structured way to manage and execute tests with distinct names.

Conclusion

While you cannot directly pass multiple test names to uvm_testname in UVM, various workarounds allow you to represent multiple test names within the test environment. Choose the approach that best suits your test structure and management requirements. By effectively managing test names, you can maintain clear test identification, robust reporting, and streamlined test execution in your UVM environment.

Can We Pass Multiple Testnames To Uvm_testname