Subversion Repositories uart2bus_testbench

//
//-----------------------------------------------------------------------------
//   Copyright 2007-2011 Mentor Graphics Corporation
//   Copyright 2007-2011 Cadence Design Systems, Inc.
//   Copyright 2010 Synopsys, Inc.
//   Copyright 2013 NVIDIA Corporation
//   All Rights Reserved Worldwide
//
//   Licensed under the Apache License, Version 2.0 (the
//   "License"); you may not use this file except in
//   compliance with the License.  You may obtain a copy of
//   the License at
//
//       http://www.apache.org/licenses/LICENSE-2.0
//
//   Unless required by applicable law or agreed to in
//   writing, software distributed under the License is
//   distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
//   CONDITIONS OF ANY KIND, either express or implied.  See
//   the License for the specific language governing
//   permissions and limitations under the License.
//-----------------------------------------------------------------------------

typedef class uvm_report_message;

// File: UVM Recorders
//
// The uvm_recorder class serves two purposes:
//  - Firstly, it is an abstract representation of a record within a
//    <uvm_tr_stream>.
//  - Secondly, it is a policy object for recording fields ~into~ that
//    record within the ~stream~.
//

//------------------------------------------------------------------------------
//
// CLASS: uvm_recorder
//
// Abstract class which defines the ~recorder~ API.
//
//------------------------------------------------------------------------------

virtual class uvm_recorder extends uvm_object;

  // Variable- m_stream_dap
  // Data access protected reference to the stream
  local uvm_set_before_get_dap#(uvm_tr_stream) m_stream_dap;

  // Variable- m_warn_null_stream
  // Used to limit the number of warnings 
  local bit m_warn_null_stream;

  // Variable- m_is_opened
  // Used to indicate recorder is open
  local bit m_is_opened;
   
  // Variable- m_is_closed
  // Used to indicate recorder is closed
  local bit m_is_closed;

  // !m_is_opened && !m_is_closed == m_is_freed

  // Variable- m_open_time
  // Used to store the open_time
  local time m_open_time;

  // Variable- m_close_time
  // Used to store the close_time
  local time m_close_time;
   
  // Variable- recording_depth
  int recording_depth;

  // Variable: default_radix
  //
  // This is the default radix setting if <record_field> is called without
  // a radix.

  uvm_radix_enum default_radix = UVM_HEX;

  // Variable: physical
  //
  // This bit provides a filtering mechanism for fields. 
  //
  // The <abstract> and physical settings allow an object to distinguish between
  // two different classes of fields. 
  //
  // It is up to you, in the <uvm_object::do_record> method, to test the
  // setting of this field if you want to use the physical trait as a filter.

  bit physical = 1;


  // Variable: abstract
  //
  // This bit provides a filtering mechanism for fields. 
  //
  // The abstract and physical settings allow an object to distinguish between
  // two different classes of fields. 
  //
  // It is up to you, in the <uvm_object::do_record> method, to test the
  // setting of this field if you want to use the abstract trait as a filter.

  bit abstract = 1;


  // Variable: identifier
  //
  // This bit is used to specify whether or not an object's reference should be
  // recorded when the object is recorded. 

  bit identifier = 1;


  // Variable: recursion_policy
  //
  // Sets the recursion policy for recording objects. 
  //
  // The default policy is deep (which means to recurse an object).

  uvm_recursion_policy_enum policy = UVM_DEFAULT_POLICY;

   // Variable- m_ids_by_recorder
   // An associative array of integers, indexed by uvm_recorders.  This
   // provides a unique 'id' or 'handle' for each recorder, which can be
   // used to identify the recorder.
   //
   // By default, neither ~m_ids_by_recorder~ or ~m_recorders_by_id~ are
   // used.  Recorders are only placed in the arrays when the user
   // attempts to determine the id for a recorder.
   local static integer m_ids_by_recorder[uvm_recorder];


  function new(string name = "uvm_recorder");
     super.new(name);
     m_stream_dap = new("stream_dap");
     m_warn_null_stream = 1;
  endfunction

   // Group: Configuration API
   
   // Function: get_stream
   // Returns a reference to the stream which created
   // this record.
   //
   // A warning will be asserted if get_stream is called prior
   // to the record being initialized via <do_open>.
   //
   function uvm_tr_stream get_stream();
      if (!m_stream_dap.try_get(get_stream)) begin
         if (m_warn_null_stream == 1) 
           `uvm_warning("UVM/REC/NO_CFG",
                        $sformatf("attempt to retrieve STREAM from '%s' before it was set!",
                                  get_name()))
         m_warn_null_stream = 0;
      end
   endfunction : get_stream

   // Group: Transaction Recorder API
   //
   // Once a recorder has been opened via <uvm_tr_stream::open_recorder>, the user
   // can ~close~ the recorder.
   //
   // Due to the fact that many database implementations will require crossing
   // a language boundary, an additional step of ~freeing~ the recorder is required.
   //
   // A ~link~ can be established within the database any time between ~open~ and
   // ~free~, however it is illegal to establish a link after ~freeing~ the recorder.
   //

   // Function: close
   // Closes this recorder.
   //
   // Closing a recorder marks the end of the transaction in the stream.
   //
   // Parameters:
   // close_time - Optional time to record as the closing time of this transaction.
   //
   // This method will trigger a <do_close> call.
   function void close(time close_time = 0);
      if (close_time == 0)
        close_time = $realtime;

      if (!is_open())
        return;

      do_close(close_time);
      
      m_is_opened = 0;
      m_is_closed = 1;
      m_close_time = close_time;
   endfunction : close

   // Function: free
   // Frees this recorder
   //
   // Freeing a recorder indicates that the stream and database can release
   // any references to the recorder.
   //
   // Parameters:
   // close_time - Optional time to record as the closing time of this transaction.
   //
   // If a recorder has not yet been closed (via a call to <close>), then
   // <close> will automatically be called, and passed the ~close_time~.  If the recorder
   // has already been closed, then the ~close_time~ will be ignored.
   //
   // This method will trigger a <do_free> call.
   function void free(time close_time = 0);
           process p=process::self();
           string s;
        
       uvm_tr_stream stream;
       
      if (!is_open() && !is_closed())
        return;

      if (is_open()) begin
         close(close_time);
      end

      do_free();

      // Clear out internal state
      stream = get_stream();
      
      m_is_closed = 0;
      if(p != null)
        s=p.get_randstate();
      m_stream_dap = new("stream_dap");
      if(p != null)
        p.set_randstate(s);
      m_warn_null_stream = 1;
      if (m_ids_by_recorder.exists(this))
        m_free_id(m_ids_by_recorder[this]);

      // Clear out stream state
      if (stream != null)
        stream.m_free_recorder(this);
   endfunction : free
      
   // Function: is_open
   // Returns true if this ~uvm_recorder~ was opened on its stream,
   // but has not yet been closed.
   //
   function bit is_open();
      return m_is_opened;
   endfunction : is_open

   // Function: get_open_time
   // Returns the ~open_time~
   //
   function time get_open_time();
      return m_open_time;
   endfunction : get_open_time

   // Function: is_closed
   // Returns true if this ~uvm_recorder~ was closed on its stream,
   // but has not yet been freed.
   //
   function bit is_closed();
      return m_is_closed;
   endfunction : is_closed
    
   // Function: get_close_time
   // Returns the ~close_time~
   //
   function time get_close_time();
      return m_close_time;
   endfunction : get_close_time

  // Function- m_do_open
  // Initializes the internal state of the recorder.
  //
  // Parameters:
  // stream - The stream which spawned this recorder
  //
  // This method will trigger a <do_open> call.
  //
  // An error will be asserted if:
  // - ~m_do_open~ is called more than once without the
  //  recorder being ~freed~ in between.
  // - ~stream~ is ~null~
  function void m_do_open(uvm_tr_stream stream, time open_time, string type_name);
     uvm_tr_stream m_stream;
     if (stream == null) begin
        `uvm_error("UVM/REC/NULL_STREAM",
                   $sformatf("Illegal attempt to set STREAM for '%s' to '<null>'",
                             this.get_name()))
        return;
     end

     if (m_stream_dap.try_get(m_stream)) begin
        `uvm_error("UVM/REC/RE_INIT",
                   $sformatf("Illegal attempt to re-initialize '%s'",
                             this.get_name()))
        return;
     end

     m_stream_dap.set(stream);
     m_open_time = open_time;
     m_is_opened = 1;
     
     do_open(stream, open_time, type_name);
  endfunction : m_do_open

   // Group: Handles


   // Variable- m_recorders_by_id
   // A corollary to ~m_ids_by_recorder~, this indexes the recorders by their
   // unique ids.
   local static uvm_recorder m_recorders_by_id[integer];

   // Variable- m_id
   // Static int marking the last assigned id.
   local static integer m_id;

   // Function- m_free_id
   // Frees the id/recorder link (memory cleanup)
   //
   static function void m_free_id(integer id);
      uvm_recorder recorder;
      if ((!$isunknown(id)) && (m_recorders_by_id.exists(id)))
        recorder = m_recorders_by_id[id];

      if (recorder != null) begin
         m_recorders_by_id.delete(id);
         m_ids_by_recorder.delete(recorder);
      end
   endfunction : m_free_id
            
   // Function: get_handle
   // Returns a unique ID for this recorder.
   //
   // A value of ~0~ indicates that the recorder has been ~freed~,
   // and no longer has a valid ID.
   //
   function integer get_handle();
      if (!is_open() && !is_closed()) begin
         return 0;
      end
      else begin
         integer handle = get_inst_id();

         // Check for the weird case where our handle changed.
         if (m_ids_by_recorder.exists(this) && m_ids_by_recorder[this] != handle)
           m_recorders_by_id.delete(m_ids_by_recorder[this]);
           
         m_recorders_by_id[handle] = this;
         m_ids_by_recorder[this] = handle;

         return handle;
      end
   endfunction : get_handle

   // Function: get_recorder_from_handle
   // Static accessor, returns a recorder reference for a given unique id.
   //
   // If no recorder exists with the given ~id~, or if the
   // recorder with that ~id~ has been freed, then ~null~ is
   // returned.
   //
   // This method can be used to access the recorder associated with a
   // call to <uvm_transaction::begin_tr> or <uvm_component::begin_tr>.
   //
   // | integer handle = tr.begin_tr();
   // | uvm_recorder recorder = uvm_recorder::get_recorder_from_handle(handle);
   // | if (recorder != null) begin
   // |   recorder.record_string("begin_msg", "Started recording transaction!");
   // | end
   //
   static function uvm_recorder get_recorder_from_handle(integer id);
      if (id == 0)
        return null;

      if (($isunknown(id)) || (!m_recorders_by_id.exists(id)))
        return null;

      return m_recorders_by_id[id];
   endfunction : get_recorder_from_handle

   // Group: Attribute Recording
   
   // Function: record_field
   // Records an integral field (less than or equal to 4096 bits).
   //
   // Parameters:
   // name - Name of the field
   // value - Value of the field to record.
   // size - Number of bits of the field which apply (Usually obtained via $bits).
   // radix - The <uvm_radix_enum> to use.
   //
   // This method will trigger a <do_record_field> call.
   function void record_field(string name,
                              uvm_bitstream_t value,
                              int size,
                              uvm_radix_enum radix=UVM_NORADIX);
      if (get_stream() == null) begin
         return;
      end
      do_record_field(name, value, size, radix);
   endfunction : record_field

   // Function: record_field_int
   // Records an integral field (less than or equal to 64 bits).
   //
   // This optimized version of <record_field> is useful for sizes up
   // to 64 bits.
   //
   // Parameters:
   // name - Name of the field
   // value - Value of the field to record
   // size - Number of bits of the wfield which apply (Usually obtained via $bits).
   // radix - The <uvm_radix_enum> to use.
   //
   // This method will trigger a <do_record_field_int> call.
   function void record_field_int(string name,
                                  uvm_integral_t value,
                                  int size,
                                  uvm_radix_enum radix=UVM_NORADIX);
        if (get_stream() == null) begin
         return;
      end
      do_record_field_int(name, value, size, radix);
   endfunction : record_field_int

   // Function: record_field_real
   // Records a real field.
   //
   // Parameters:
   // name - Name of the field
   // value - Value of the field to record
   //
   // This method will trigger a <do_record_field_real> call.
   function void record_field_real(string name,
                                   real value);
      if (get_stream() == null) begin
         return;
      end
      do_record_field_real(name, value);
   endfunction : record_field_real

   // Function: record_object
   // Records an object field.
   //
   // Parameters:
   // name - Name of the field
   // value - Object to record
   //
   // The implementation must use the <recursion_policy> and <identifier> to
   // determine exactly what should be recorded.
   function void record_object(string name,
                               uvm_object value);
      if (get_stream() == null) begin
         return;
      end
      
      do_record_object(name, value);
   endfunction : record_object

   // Function: record_string
   // Records a string field.
   //
   // Parameters:
   // name - Name of the field
   // value - Value of the field
   //
   function void record_string(string name,
                               string value);
      if (get_stream() == null) begin
         return;
      end

      do_record_string(name, value);
   endfunction : record_string
   
   // Function: record_time
   // Records a time field.
   //
   // Parameters:
   // name - Name of the field
   // value - Value of the field
   //
   function void record_time(string name,
                             time value);
      if (get_stream() == null) begin
         return;
      end

      do_record_time(name, value);
   endfunction : record_time
   
   // Function: record_generic
   // Records a name/value pair, where ~value~ has been converted to a string.
   //
   // For example:
   //| recorder.record_generic("myvar","var_type", $sformatf("%0d",myvar), 32);
   //
   // Parameters:
   // name - Name of the field
   // value - Value of the field
   // type_name - ~optional~ Type name of the field
   function void record_generic(string name,
                                string value,
                                string type_name="");
      if (get_stream() == null) begin
         return;
      end

      do_record_generic(name, value, type_name);
   endfunction : record_generic

  // Function: use_record_attribute
  //
  // Indicates that this recorder does (or does not) support usage of
  // the <`uvm_record_attribute> macro.
  //
  // The default return value is ~0~ (not supported), developers can
  // optionally extend ~uvm_recorder~ and set the value to ~1~ if they
  // support the <`uvm_record_attribute> macro.
  virtual function bit use_record_attribute();
     return 0;
  endfunction : use_record_attribute

   // Function: get_record_attribute_handle
   // Provides a tool-specific handle which is compatible with <`uvm_record_attribute>.
   //
   // By default, this method will return the same value as <get_handle>,
   // however tool vendors can override this method to provide tool-specific handles
   // which will be passed to the <`uvm_record_attribute> macro.
   //
   virtual function integer get_record_attribute_handle();
      return get_handle();
   endfunction : get_record_attribute_handle
   
   // Group: Implementation Agnostic API

   // Function: do_open
   // Callback triggered via <uvm_tr_stream::open_recorder>.
   //
   // The ~do_open~ callback can be used to initialize any internal
   // state within the recorder, as well as providing a location to
   // record any initial information.
   protected virtual function void do_open(uvm_tr_stream stream,
                                             time open_time,
                                             string type_name);
   endfunction : do_open

   // Function: do_close
   // Callback triggered via <close>.
   //
   // The ~do_close~ callback can be used to set internal state
   // within the recorder, as well as providing a location to
   // record any closing information.
   protected virtual function void do_close(time close_time);
   endfunction : do_close

   // Function: do_free
   // Callback triggered via <free>.
   //
   // The ~do_free~ callback can be used to release the internal
   // state within the recorder, as well as providing a location
   // to record any "freeing" information.
   protected virtual function void do_free();
   endfunction : do_free
   
   // Function: do_record_field
   // Records an integral field (less than or equal to 4096 bits).
   //
   // ~Mandatory~ Backend implementation of <record_field>
   pure virtual protected function void do_record_field(string name,
                                                        uvm_bitstream_t value,
                                                        int size,
                                                        uvm_radix_enum radix);

   // Function: do_record_field_int
   // Records an integral field (less than or equal to 64 bits).
   //
   // ~Mandatory~ Backend implementation of <record_field_int>
   pure virtual protected function void do_record_field_int(string name,
                                                            uvm_integral_t value,
                                                            int          size,
                                                            uvm_radix_enum radix);
   
   // Function: do_record_field_real
   // Records a real field.
   //
   // ~Mandatory~ Backend implementation of <record_field_real>
   pure virtual protected function void do_record_field_real(string name,
                                                             real value);

   // Function: do_record_object
   // Records an object field.
   //
   // ~Mandatory~ Backend implementation of <record_object>
   pure virtual protected function void do_record_object(string name,
                                                         uvm_object value);

   // Function: do_record_string
   // Records a string field.
   //
   // ~Mandatory~ Backend implementation of <record_string>
   pure virtual protected function void do_record_string(string name,
                                                         string value);

   // Function: do_record_time
   // Records a time field.
   //
   // ~Mandatory~ Backend implementation of <record_time>
   pure virtual protected function void do_record_time(string name,
                                                       time value);

   // Function: do_record_generic
   // Records a name/value pair, where ~value~ has been converted to a string.
   //
   // ~Mandatory~ Backend implementation of <record_generic>
   pure virtual protected function void do_record_generic(string name,
                                                          string value,
                                                          string type_name);


   // The following code is primarily for backwards compat. purposes.  "Transaction
   // Handles" are useful when connecting to a backend, but when passing the information
   // back and forth within simulation, it is safer to user the ~recorder~ itself
   // as a reference to the transaction within the database.

   //------------------------------
   // Group- Vendor-Independent API
   //------------------------------


  // UVM provides only a text-based default implementation.
  // Vendors provide subtype implementations and overwrite the
  // <uvm_default_recorder> handle.


  // Function- open_file
  //
  // Opens the file in the <filename> property and assigns to the
  // file descriptor <file>.
  //
  virtual function bit open_file();
     return 0;
  endfunction

  // Function- create_stream
  //
  //
  virtual function integer create_stream (string name,
                                          string t,
                                          string scope);
     return -1;
  endfunction

   
  // Function- m_set_attribute
  //
  //
  virtual function void m_set_attribute (integer txh,
                                 string nm,
                                 string value);
  endfunction
  
  
  // Function- set_attribute
  //
  virtual function void set_attribute (integer txh,
                               string nm,
                               logic [1023:0] value,
                               uvm_radix_enum radix,
                               integer numbits=1024);
  endfunction
  
  
  // Function- check_handle_kind
  //
  //
  virtual function integer check_handle_kind (string htype, integer handle);
     return 0;
  endfunction
  
  
  // Function- begin_tr
  //
  //
  virtual function integer begin_tr(string txtype,
                                     integer stream,
                                     string nm,
                                     string label="",
                                     string desc="",
                                     time begin_time=0);
    return -1;
  endfunction
  
  
  // Function- end_tr
  //
  //
  virtual function void end_tr (integer handle, time end_time=0);
  endfunction
  
  
  // Function- link_tr
  //
  //
  virtual function void link_tr(integer h1,
                                 integer h2,
                                 string relation="");
  endfunction
  
  
  
  // Function- free_tr
  //
  //
  virtual function void free_tr(integer handle);
  endfunction
  
endclass // uvm_recorder

//------------------------------------------------------------------------------
//
// CLASS: uvm_text_recorder
//
// The ~uvm_text_recorder~ is the default recorder implementation for the
// <uvm_text_tr_database>.
//

class uvm_text_recorder extends uvm_recorder;

   `uvm_object_utils(uvm_text_recorder)

   // Variable- m_text_db
   //
   // Reference to the text database backend
   uvm_text_tr_database m_text_db;

   // Variable- scope
   // Imeplementation detail
   uvm_scope_stack scope = new;

   // Function: new
   // Constructor
   //
   // Parameters:
   // name - Instance name
   function new(string name="unnamed-uvm_text_recorder");
      super.new(name);
   endfunction : new

   // Group: Implementation Agnostic API

   // Function: do_open
   // Callback triggered via <uvm_tr_stream::open_recorder>.
   //
   // Text-backend specific implementation.
   protected virtual function void do_open(uvm_tr_stream stream,
                                             time open_time,
                                             string type_name);
      $cast(m_text_db, stream.get_db());
      if (m_text_db.open_db())
        $fdisplay(m_text_db.m_file, 
                  "    OPEN_RECORDER @%0t {TXH:%0d STREAM:%0d NAME:%s TIME:%0t TYPE=\"%0s\"}",
                  $realtime,
                  this.get_handle(),
                  stream.get_handle(),
                  this.get_name(),
                  open_time,
                  type_name);
   endfunction : do_open

   // Function: do_close
   // Callback triggered via <uvm_recorder::close>.
   //
   // Text-backend specific implementation.
   protected virtual function void do_close(time close_time);
      if (m_text_db.open_db()) begin
         $fdisplay(m_text_db.m_file, 
                   "    CLOSE_RECORDER @%0t {TXH:%0d TIME=%0t}",
                   $realtime,
                   this.get_handle(),
                   close_time);
         
      end
   endfunction : do_close

   // Function: do_free
   // Callback triggered via <uvm_recorder::free>.
   //
   // Text-backend specific implementation.
   protected virtual function void do_free();
      if (m_text_db.open_db()) begin
         $fdisplay(m_text_db.m_file, 
                   "    FREE_RECORDER @%0t {TXH:%0d}",
                   $realtime,
                   this.get_handle());
      end
      m_text_db = null;
   endfunction : do_free
   
   // Function: do_record_field
   // Records an integral field (less than or equal to 4096 bits).
   //
   // Text-backend specific implementation.
   protected virtual function void do_record_field(string name,
                                                   uvm_bitstream_t value,
                                                   int size,
                                                   uvm_radix_enum radix);
      scope.set_arg(name);
      if (!radix)
        radix = default_radix;

      write_attribute(scope.get(),
                      value,
                      radix,
                      size);

   endfunction : do_record_field
  
   
   // Function: do_record_field_int
   // Records an integral field (less than or equal to 64 bits).
   //
   // Text-backend specific implementation.
   protected virtual function void do_record_field_int(string name,
                                                       uvm_integral_t value,
                                                       int          size,
                                                       uvm_radix_enum radix);
      scope.set_arg(name);
      if (!radix)
        radix = default_radix;

      write_attribute_int(scope.get(),
                          value,
                          radix,
                          size);

   endfunction : do_record_field_int


   // Function: do_record_field_real
   // Record a real field.
   //
   // Text-backened specific implementation.
   protected virtual function void do_record_field_real(string name,
                                                        real value);
      bit [63:0] ival = $realtobits(value);
      scope.set_arg(name);

      write_attribute_int(scope.get(),
                          ival,
                          UVM_REAL,
                          64);
   endfunction : do_record_field_real

   // Function: do_record_object
   // Record an object field.
   //
   // Text-backend specific implementation.
   //
   // The method uses ~identifier~ to determine whether or not to
   // record the object instance id, and ~recursion_policy~ to
   // determine whether or not to recurse into the object.
   protected virtual function void do_record_object(string name,
                                                    uvm_object value);
      int            v;
      string         str;
      
      if(identifier) begin 
         if(value != null) begin
            $swrite(str, "%0d", value.get_inst_id());
            v = str.atoi(); 
         end
         scope.set_arg(name);
         write_attribute_int(scope.get(), 
                             v, 
                             UVM_DEC, 
                             32);
      end
 
      if(policy != UVM_REFERENCE) begin
         if(value!=null) begin
            if(value.__m_uvm_status_container.cycle_check.exists(value)) return;
            value.__m_uvm_status_container.cycle_check[value] = 1;
            scope.down(name);
            value.record(this);
            scope.up();
            value.__m_uvm_status_container.cycle_check.delete(value);
         end
      end
   endfunction : do_record_object

   // Function: do_record_string
   // Records a string field.
   //
   // Text-backend specific implementation.
   protected virtual function void do_record_string(string name,
                                                    string value);
      scope.set_arg(name);
      if (m_text_db.open_db()) begin
         $fdisplay(m_text_db.m_file, 
                   "      SET_ATTR @%0t {TXH:%0d NAME:%s VALUE:%s   RADIX:%s BITS=%0d}",
                   $realtime,
                   this.get_handle(),
                   scope.get(),
                   value,
                   "UVM_STRING",
                   8+value.len());
      end
   endfunction : do_record_string

   // Function: do_record_time
   // Records a time field.
   //
   // Text-backend specific implementation.
   protected virtual function void do_record_time(string name,
                                                    time value);
      scope.set_arg(name);
      write_attribute_int(scope.get(), 
                          value,
                          UVM_TIME, 
                          64);
   endfunction : do_record_time

   // Function: do_record_generic
   // Records a name/value pair, where ~value~ has been converted to a string.
   //
   // Text-backend specific implementation.
   protected virtual function void do_record_generic(string name,
                                                     string value,
                                                     string type_name);
      scope.set_arg(name);
      write_attribute(scope.get(), 
                      uvm_string_to_bits(value), 
                      UVM_STRING, 
                      8+value.len());
   endfunction : do_record_generic

   // Group: Implementation Specific API
   
   // Function: write_attribute
   // Outputs an integral attribute to the textual log
   //
   // Parameters:
   // nm - Name of the attribute
   // value - Value
   // radix - Radix of the output
   // numbits - number of valid bits
   function void write_attribute(string nm,
                                 uvm_bitstream_t value,
                                 uvm_radix_enum radix,
                                 integer numbits=$bits(uvm_bitstream_t));
      if (m_text_db.open_db()) begin
         $fdisplay(m_text_db.m_file, 
                   "      SET_ATTR @%0t {TXH:%0d NAME:%s VALUE:%s   RADIX:%s BITS=%0d}",
                   $realtime,
                   this.get_handle(),
                   nm,
                   uvm_bitstream_to_string(value, numbits, radix),
                    radix.name(),
                   numbits);
      end
   endfunction : write_attribute

   // Function: write_attribute_int
   // Outputs an integral attribute to the textual log
   //
   // Parameters:
   // nm - Name of the attribute
   // value - Value
   // radix - Radix of the output
   // numbits - number of valid bits
   function void write_attribute_int(string  nm,
                                     uvm_integral_t value,
                                     uvm_radix_enum radix,
                                     integer numbits=$bits(uvm_bitstream_t));
      if (m_text_db.open_db()) begin
         $fdisplay(m_text_db.m_file, 
                   "      SET_ATTR @%0t {TXH:%0d NAME:%s VALUE:%s   RADIX:%s BITS=%0d}",
                   $realtime,
                   this.get_handle(),
                   nm,
                   uvm_integral_to_string(value, numbits, radix),
                   radix.name(),
                   numbits);
      end
   endfunction : write_attribute_int

   /// LEFT FOR BACKWARDS COMPAT ONLY!!!!!!!!

   //------------------------------
   // Group- Vendor-Independent API
   //------------------------------


  // UVM provides only a text-based default implementation.
  // Vendors provide subtype implementations and overwrite the
  // <uvm_default_recorder> handle.

   string                                                   filename;
   bit                                                      filename_set;

  // Function- open_file
  //
  // Opens the file in the <filename> property and assigns to the
  // file descriptor <file>.
  //
  virtual function bit open_file();
     if (!filename_set) begin
        m_text_db.set_file_name(filename);
     end
     return m_text_db.open_db();
  endfunction


  // Function- create_stream
  //
  //
  virtual function integer create_stream (string name,
                                          string t,
                                          string scope);
     uvm_text_tr_stream stream;
     if (open_file()) begin
        $cast(stream,m_text_db.open_stream(name, scope, t));
        return stream.get_handle();
     end
     return 0;
  endfunction

   
  // Function- m_set_attribute
  //
  //
  virtual function void m_set_attribute (integer txh,
                                 string nm,
                                 string value);
     if (open_file()) begin
        UVM_FILE file = m_text_db.m_file;
        $fdisplay(file,"      SET_ATTR @%0t {TXH:%0d NAME:%s VALUE:%s}", $realtime,txh,nm,value);
     end
  endfunction
  
  
  // Function- set_attribute
  //
  //
  virtual function void set_attribute (integer txh,
                               string nm,
                               logic [1023:0] value,
                               uvm_radix_enum radix,
                               integer numbits=1024);
     if (open_file()) begin
        UVM_FILE file = m_text_db.m_file;
         $fdisplay(file, 
                   "      SET_ATTR @%0t {TXH:%0d NAME:%s VALUE:%s   RADIX:%s BITS=%0d}",
                   $realtime,
                   txh,
                   nm,
                   uvm_bitstream_to_string(value, numbits, radix),
                   radix.name(),
                   numbits);
        
     end
  endfunction
  
  
  // Function- check_handle_kind
  //
  //
  virtual function integer check_handle_kind (string htype, integer handle);
     return ((uvm_recorder::get_recorder_from_handle(handle) != null) ||
             (uvm_tr_stream::get_stream_from_handle(handle) != null));
  endfunction
  
  
  // Function- begin_tr
  //
  //
  virtual function integer begin_tr(string txtype,
                                     integer stream,
                                     string nm,
                                     string label="",
                                     string desc="",
                                     time begin_time=0);
     if (open_file()) begin
        uvm_tr_stream stream_obj = uvm_tr_stream::get_stream_from_handle(stream);
        uvm_recorder recorder;
  
        if (stream_obj == null)
          return -1;

        recorder = stream_obj.open_recorder(nm, begin_time, txtype);

        return recorder.get_handle();
     end
     return -1;
  endfunction
  
  
  // Function- end_tr
  //
  //
  virtual function void end_tr (integer handle, time end_time=0);
     if (open_file()) begin
        uvm_recorder record = uvm_recorder::get_recorder_from_handle(handle);
        if (record != null) begin
           record.close(end_time);
        end
     end
  endfunction
  
  
  // Function- link_tr
  //
  //
  virtual function void link_tr(integer h1,
                                 integer h2,
                                 string relation="");
    if (open_file())
      $fdisplay(m_text_db.m_file,"  LINK @%0t {TXH1:%0d TXH2:%0d RELATION=%0s}", $realtime,h1,h2,relation);
  endfunction
  
  
  
  // Function- free_tr
  //
  //
  virtual function void free_tr(integer handle);
     if (open_file()) begin
        uvm_recorder record = uvm_recorder::get_recorder_from_handle(handle);
        if (record != null) begin
           record.free();
        end
     end
  endfunction // free_tr

endclass : uvm_text_recorder