uvm_pair¶

Title: UVMPair classes

This section defines container classes for handling value pairs.

class uvm.comps.uvm_pair.UVMClassPair(name='', f=None, s=None)[source]¶

Bases: UVMObject

Class: UVMClassPair

Container holding handles to two objects whose types are specified by the type parameters, T1 and T2.

type_name = 'UVMClassPair'¶

convert2string()[source]¶

This virtual function is a user-definable hook, called directly by the user, that allows users to provide object information in the form of a string. Unlike sprint, there is no requirement to use a uvm_printer policy object. As such, the format and content of the output is fully customizable, which may be suitable for applications not requiring the consistent formatting offered by the print/sprint/do_print API.

Fields declared in <Utility Macros> macros (`uvm_field_*), if used, will not automatically appear in calls to convert2string.

An example implementation of convert2string follows.
 class Base(UVMObject):
   field = "foo"
   def convert2string(self):
     return "base_field=" + self.field

 class Obj2(UVMObject):
   field = "bar"
   def convert2string()
     convert2string = "child_field=" + self.field

 class Obj(Base):
   addr = 0x123
   data = 0x456
   write = 1
   child = Obj2()
   def convert2string(self):
      convert2string = super().convert2string() +
        sv.sformatf(" write=%0d addr=%8h data=%8h ",write,addr,data) +
        child.convert2string()

Then, to display an object, you could write:

.. code-block:: python

  o = Obj()
  uvm_report_info("BusMaster", "Sending:

” + o.convert2string())

The output will look similar to:
UVM_INFO @ 0: reporter [BusMaster] Sending:
  base_field=foo write=1 addr=00000123 data=00000456 child_field=bar
Returns:
str: Object converted into string.

create(name='')¶

Group: Creation

The create method allocates a new object of the same type as this object and returns it via a base uvm_object handle. Every class deriving from uvm_object, directly or indirectly, must implement the create method.

A typical implementation is as follows:

class mytype (UVMObject):
  ...
  def create(self, name=""):
    mytype t = mytype(name)
    return t

Parameters: name (str) – Name of the created object.
Returns: New object.
Return type: obj

get_object_type()¶

Function: get_object_type

Returns the type-proxy (wrapper) for this object. The uvm_factory’s type-based override and creation methods take arguments of uvm_object_wrapper. This method, if implemented, can be used as convenient means of supplying those arguments. This method is the same as the static get_type method, but uses an already allocated object to determine the type-proxy to access (instead of using the static object).

The default implementation of this method does a factory lookup of the proxy using the return value from get_type_name. If the type returned by get_type_name is not registered with the factory, then a None handle is returned.

For example:

class cmd (UVMObject):
  type_id = UVMObjectRegistry()
  @classmethod
  def type_id get_type(cls):
    return type_id.get()
  def get_object_type(self):
    return cmd.type_id.get()

This function is implemented by the `uvm_*_utils macros, if employed.

Returns:

classmethod get_type()¶

Returns the type-proxy (wrapper) for this object. The UVMFactory’s type-based override and creation methods take arguments of uvm_object_wrapper. This method, if implemented, can be used as convenient means of supplying those arguments.

The default implementation of this method produces an error and returns None. To enable use of this method, a user’s subtype must implement a version that returns the subtype’s wrapper.

For example:

class cmd(UVMObject):
  type_id = None

  @classmethod
  def get_type(cls):
    return cls.type_id.get()

Then, to use:

factory.set_type_override(cmd.get_type(), subcmd.get_type())

This function is implemented by the uvm_*_utils functions, if employed.

Returns:

get_type_name()¶

This function returns the type name of the object, which is typically the type identifier enclosed in quotes. It is used for various debugging functions in the library, and it is used by the factory for creating objects.

This function must be defined in every derived class.

A typical implementation is as follows:

class mytype (UVMObject):
  ...
  type_name = "mytype"

  def get_type_name(self):
    return my_type.type_name

We define the type_name static variable to enable access to the type name without need of an object of the class, i.e., to enable access via the scope operator, ~mytype::type_name~.

Returns: Type name of the object.
Return type: str

type_id = <uvm.base.uvm_registry.UVMObjectRegistry object>¶

class uvm.comps.uvm_pair.UVMBuiltInPair(name='')[source]¶

Bases: UVMObject

type_name = 'UVMBuiltInPair'¶

get_type_name()¶

This function returns the type name of the object, which is typically the type identifier enclosed in quotes. It is used for various debugging functions in the library, and it is used by the factory for creating objects.

This function must be defined in every derived class.

A typical implementation is as follows:

class mytype (UVMObject):
  ...
  type_name = "mytype"

  def get_type_name(self):
    return my_type.type_name

We define the type_name static variable to enable access to the type name without need of an object of the class, i.e., to enable access via the scope operator, ~mytype::type_name~.

Returns: Type name of the object.
Return type: str

convert2string()[source]¶

This virtual function is a user-definable hook, called directly by the user, that allows users to provide object information in the form of a string. Unlike sprint, there is no requirement to use a uvm_printer policy object. As such, the format and content of the output is fully customizable, which may be suitable for applications not requiring the consistent formatting offered by the print/sprint/do_print API.

Fields declared in <Utility Macros> macros (`uvm_field_*), if used, will not automatically appear in calls to convert2string.

An example implementation of convert2string follows.
 class Base(UVMObject):
   field = "foo"
   def convert2string(self):
     return "base_field=" + self.field

 class Obj2(UVMObject):
   field = "bar"
   def convert2string()
     convert2string = "child_field=" + self.field

 class Obj(Base):
   addr = 0x123
   data = 0x456
   write = 1
   child = Obj2()
   def convert2string(self):
      convert2string = super().convert2string() +
        sv.sformatf(" write=%0d addr=%8h data=%8h ",write,addr,data) +
        child.convert2string()

Then, to display an object, you could write:

.. code-block:: python

  o = Obj()
  uvm_report_info("BusMaster", "Sending:

” + o.convert2string())

The output will look similar to:
UVM_INFO @ 0: reporter [BusMaster] Sending:
  base_field=foo write=1 addr=00000123 data=00000456 child_field=bar
Returns:
str: Object converted into string.

do_compare(rhs, comparer)[source]¶

The do_compare method is the user-definable hook called by the compare method. A derived class should override this method to include its fields in a compare operation. It should return 1 if the comparison succeeds, 0 otherwise.

A typical implementation is as follows:

class mytype (UVMObject):
  ...
  f1 = 0
  def do_compare(self, rhs, comparer):
    do_compare = super.do_compare(rhs,comparer)
    # Optional type checking
    do_compare &= comparer.compare_field_int("f1", f1, rhs.f1)
    return do_compare

A derived class implementation must call super().do_compare to ensure its base class’ properties, if any, are included in the comparison. If type matching is required instead of duck-typing, the user can also implemented this checking.

The actual comparison should be implemented using the UVMComparer object rather than direct field-by-field comparison. This enables users of your class to customize how comparisons are performed and how much miscompare information is collected. See UVMComparer for more details.

Parameters

rhs (UVMObject) –
comparer (UVMComparer) –

Returns

True if objects match, False otherwise.

Return type

bool

create(name='')¶

Group: Creation

The create method allocates a new object of the same type as this object and returns it via a base uvm_object handle. Every class deriving from uvm_object, directly or indirectly, must implement the create method.

A typical implementation is as follows:

class mytype (UVMObject):
  ...
  def create(self, name=""):
    mytype t = mytype(name)
    return t

Parameters: name (str) – Name of the created object.
Returns: New object.
Return type: obj

get_object_type()¶

Function: get_object_type

Returns the type-proxy (wrapper) for this object. The uvm_factory’s type-based override and creation methods take arguments of uvm_object_wrapper. This method, if implemented, can be used as convenient means of supplying those arguments. This method is the same as the static get_type method, but uses an already allocated object to determine the type-proxy to access (instead of using the static object).

The default implementation of this method does a factory lookup of the proxy using the return value from get_type_name. If the type returned by get_type_name is not registered with the factory, then a None handle is returned.

For example:

class cmd (UVMObject):
  type_id = UVMObjectRegistry()
  @classmethod
  def type_id get_type(cls):
    return type_id.get()
  def get_object_type(self):
    return cmd.type_id.get()

This function is implemented by the `uvm_*_utils macros, if employed.

Returns:

classmethod get_type()¶

Returns the type-proxy (wrapper) for this object. The UVMFactory’s type-based override and creation methods take arguments of uvm_object_wrapper. This method, if implemented, can be used as convenient means of supplying those arguments.

The default implementation of this method produces an error and returns None. To enable use of this method, a user’s subtype must implement a version that returns the subtype’s wrapper.

For example:

class cmd(UVMObject):
  type_id = None

  @classmethod
  def get_type(cls):
    return cls.type_id.get()

Then, to use:

factory.set_type_override(cmd.get_type(), subcmd.get_type())

This function is implemented by the uvm_*_utils functions, if employed.

Returns:

type_id = <uvm.base.uvm_registry.UVMObjectRegistry object>¶