foo1.cs

        var isInGeneratedCode = IsInGeneratedCode(node, parameters.RegionsInfo);

        UsageState state;
        if (isInGeneratedCode != null)
        {
          state = (bool) isInGeneratedCode
            ? UsageState.METHOD_ASSIGNED_TO_DELEGATE_IN_GENERATED_CODE
            : UsageState.METHOD_ASSIGNED_TO_DELEGATE_IN_USER_CODE;
        }
        else
        {
          state = UsageState.METHOD_ASSIGNED_TO_DELEGATE_MASK;
        }

        parameters.UsageData.SetElementState(method, state);

foo2.cs

        var state = IsInGeneratedCode(node, parameters.RegionsInfo) switch {
          true  => UsageState.METHOD_ASSIGNED_TO_DELEGATE_IN_GENERATED_CODE,
          false => UsageState.METHOD_ASSIGNED_TO_DELEGATE_IN_USER_CODE,
          null  => UsageState.METHOD_ASSIGNED_TO_DELEGATE_MASK
        };

        parameters.UsageData.SetElementState(method, state);