Disabling printing for a single field within UVM utility macros requires a nuanced approach, as the default behavior is to print all fields. There isn't a single, universally applicable solution, as the specific method depends on the utility macro you're using and how it's implemented. However, we can explore several strategies to achieve this goal.
Understanding UVM Utility Macros and Printing
UVM (Universal Verification Methodology) utility macros, such as uvm_info, uvm_warning, uvm_error, etc., are designed for reporting and debugging within a verification environment. By default, they typically print information about the object and its associated fields. The level of detail printed depends on the severity level and the verbosity settings.
However, directly disabling printing for only one field within a complex object printed by a macro isn't a direct feature. The macros typically operate on the entire object or a specified subset of fields determined by the object's display() method. Therefore, we need to work around this limitation.
Strategies to Control Printing
Here are several approaches to selectively suppress printing for a particular field:
1. Overriding the display() Method
This is arguably the most effective and clean approach. You can create a derived class of your original object and override its display() method. In this overridden method, you explicitly exclude the field you want to hide from the output.
class my_object extends uvm_object;
rand bit [7:0] field_a;
rand bit [15:0] field_b; // This field we want to suppress
function void display(string prefix = "");
$display("%sfield_a: %h", prefix, field_a);
// Exclude field_b from display
endfunction
function new(string name = "my_object");
super.new(name);
endfunction
endclass
This method ensures that only the desired fields are printed, giving you fine-grained control over the output.
2. Conditional Printing within the display() Method (If Applicable)
If you don't have control over the object's class, you might be able to modify the existing display() method (if you have access to its source code) to conditionally print fields based on a flag or a specific condition.
function void display(string prefix = "");
if (!suppress_field_b)
$display("%sfield_b: %h", prefix, field_b);
$display("%sfield_a: %h", prefix, field_a);
endfunction
This requires careful management of the suppress_field_b flag throughout your code.
3. Using a Separate Reporting Mechanism
For more complex scenarios, consider creating a custom reporting mechanism. This approach involves writing your own functions or tasks to log the data you require, selectively excluding specific fields. This offers maximal flexibility, though it adds complexity.
4. Adjusting Verbosity Levels (Less Precise)
While not ideal for targeting a single field, you could adjust the verbosity level of the UVM reporting. This might suppress the output of certain fields if they are printed at a lower verbosity level than the currently configured one. However, this is a coarse-grained approach and may suppress other useful information.
Choosing the Right Approach
The best approach depends heavily on your context:
- Overriding
display(): This is generally the preferred method if you can modify the object's class. It's clean, efficient, and offers precise control. - Conditional Printing: Useful if you have limited control over the object's definition but can modify its
display()method. - Custom Reporting: Provides the highest flexibility but introduces more code and potential complexity.
- Adjusting Verbosity: Only suitable as a last resort, as it’s a blunt instrument.
Remember to always consider maintainability and readability when choosing your approach. Carefully documenting any changes you make to the existing code is crucial for collaboration and future debugging.
