base class of all object containers. More...

#include <object.h>

Inheritance diagram for tvm::runtime::Object:

Collaboration diagram for tvm::runtime::Object:

Public Types
typedef void(*	FDeleter) (Object *self)
	Object deleter. More...

using	RefCounterType = std::atomic< int32_t >

Public Member Functions
uint32_t	type_index () const

std::string	GetTypeKey () const

size_t	GetTypeKeyHash () const

template<typename TargetType >
bool	IsInstance () const

bool	unique () const

	Object ()

	Object (const Object &other)

	Object (Object &&other)

Object &	operator= (const Object &other)

Object &	operator= (Object &&other)

Static Public Member Functions
static std::string	TypeIndex2Key (uint32_t tindex)
	Get the type key of the corresponding index from runtime. More...

static size_t	TypeIndex2KeyHash (uint32_t tindex)
	Get the type key hash of the corresponding index from runtime. More...

static uint32_t	TypeKey2Index (const std::string &key)
	Get the type index of the corresponding key from runtime. More...

static uint32_t	_GetOrAllocRuntimeTypeIndex ()

static uint32_t	RuntimeTypeIndex ()

Static Public Attributes
static constexpr const char *	_type_key = "runtime.Object"

static constexpr bool	_type_final = false

static constexpr uint32_t	_type_child_slots = 0

static constexpr bool	_type_child_slots_can_overflow = true

static constexpr bool	_type_has_method_visit_attrs = true

static constexpr bool	_type_has_method_sequal_reduce = false

static constexpr bool	_type_has_method_shash_reduce = false

static constexpr uint32_t	_type_index = TypeIndex::kDynamic

Protected Member Functions
void	IncRef ()
	developer function, increases reference counter. More...

void	DecRef ()
	developer function, decrease reference counter. More...

Static Protected Member Functions
static uint32_t	GetOrAllocRuntimeTypeIndex (const std::string &key, uint32_t static_tindex, uint32_t parent_tindex, uint32_t type_child_slots, bool type_child_slots_can_overflow)
	Get the type index using type key. More...

Protected Attributes
uint32_t	type_index_ {0}
	Type index(tag) that indicates the type of the object. More...

RefCounterType	ref_counter_ {0}
	The internal reference counter. More...

FDeleter	deleter_ = nullptr
	deleter of this object to enable customized allocation. If the deleter is nullptr, no deletion will be performed. The creator of the object must always set the deleter field properly. More...

Friends
template<typename >
class	ObjAllocatorBase

template<typename >
class	ObjectPtr

class	TVMRetValue

class	ObjectInternal

Detailed Description

base class of all object containers.

Sub-class of objects should declare the following static constexpr fields:

_type_index: Static type index of the object, if assigned to TypeIndex::kDynamic the type index will be assigned during runtime. Runtime type index can be accessed by ObjectType::TypeIndex();
_type_key: The unique string identifier of the type.
_type_final: Whether the type is terminal type(there is no subclass of the type in the object system). This field is automatically set by macro TVM_DECLARE_FINAL_OBJECT_INFO It is still OK to sub-class a terminal object type T and construct it using make_object. But IsInstance check will only show that the object type is T(instead of the sub-class).

The following two fields are necessary for base classes that can be sub-classed.

_type_child_slots: Number of reserved type index slots for child classes. Used for runtime optimization for type checking in IsInstance. If an object's type_index is within range of [type_index, type_index + _type_child_slots] Then the object can be quickly decided as sub-class of the current object class. If not, a fallback mechanism is used to check the global type table. Recommendation: set to estimate number of children needed.
_type_child_slots_can_overflow: Whether we can add additional child classes even if the number of child classes exceeds the _type_child_slots. A fallback mechanism to check global type table will be used. Recommendation: set to false for optimal runtime speed if we know exact number of children.

Two macros are used to declare helper functions in the object:

Use TVM_DECLARE_BASE_OBJECT_INFO for object classes that can be sub-classed.
Use TVM_DECLARE_FINAL_OBJECT_INFO for object classes that cannot be sub-classed.

New objects can be created using make_object function. Which will automatically populate the type_index and deleter of the object.

See also: make_object; ObjectPtr; ObjectRef

// Create a base object
class BaseObj : public Object {
 public:
  // object fields
  int field0;
 
  // object properties
  static constexpr const uint32_t _type_index = TypeIndex::kDynamic;
  static constexpr const char* _type_key = "test.BaseObj";
  TVM_DECLARE_BASE_OBJECT_INFO(BaseObj, Object);
};
 
class LeafObj : public BaseObj {
 public:
  // fields
  int child_field0;
  // object properties
  static constexpr const uint32_t _type_index = TypeIndex::kDynamic;
  static constexpr const char* _type_key = "test.LeafObj";
  TVM_DECLARE_BASE_OBJECT_INFO(LeafObj, Object);
};
 
// The following code should be put into a cc file.
TVM_REGISTER_OBJECT_TYPE(BaseObj);
TVM_REGISTER_OBJECT_TYPE(LeafObj);
 
// Usage example.
void TestObjects() {
  // create an object
  ObjectRef leaf_ref(make_object<LeafObj>());
  // cast to a specific instance
  const LeafObj* leaf_ptr = leaf_ref.as<LeafObj>();
  ICHECK(leaf_ptr != nullptr);
  // can also cast to the base class.
  ICHECK(leaf_ref.as<BaseObj>() != nullptr);
}

Member Typedef Documentation

◆ FDeleter

typedef void(* tvm::runtime::Object::FDeleter) (Object *self)

Object deleter.

Parameters

self	pointer to the Object.

◆ RefCounterType

using tvm::runtime::Object::RefCounterType = std::atomic<int32_t>

Constructor & Destructor Documentation

◆ Object() [1/3]

tvm::runtime::Object::Object ( )

inline

◆ Object() [2/3]

tvm::runtime::Object::Object ( const Object & other )

inline

◆ Object() [3/3]

tvm::runtime::Object::Object ( Object && other )

inline

Member Function Documentation

◆ _GetOrAllocRuntimeTypeIndex()

static uint32_t tvm::runtime::Object::_GetOrAllocRuntimeTypeIndex ( )

inlinestatic

◆ DecRef()

void tvm::runtime::Object::DecRef ( )

inlineprotected

developer function, decrease reference counter.

Note: The deleter will be called when ref_counter_ becomes zero.

◆ GetOrAllocRuntimeTypeIndex()

static uint32_t tvm::runtime::Object::GetOrAllocRuntimeTypeIndex	(	const std::string &	key,
		uint32_t	static_tindex,
		uint32_t	parent_tindex,
		uint32_t	type_child_slots,
		bool	type_child_slots_can_overflow
	)

staticprotected

Get the type index using type key.

When the function is first time called for a type, it will register the type to the type table in the runtime. If the static_tindex is TypeIndex::kDynamic, the function will allocate a runtime type index. Otherwise, we will populate the type table and return the static index.

Parameters

key	the type key.
static_tindex	The current _type_index field. can be TypeIndex::kDynamic.
parent_tindex	The index of the parent.
type_child_slots	Number of slots reserved for its children.
type_child_slots_can_overflow	Whether to allow child to overflow the slots.

Returns: The allocated type index.

◆ GetTypeKey()

std::string tvm::runtime::Object::GetTypeKey ( ) const

inline

Returns: the type key of the object.

Note: this operation is expensive, can be used for error reporting.

◆ GetTypeKeyHash()

size_t tvm::runtime::Object::GetTypeKeyHash ( ) const

inline

Returns: A hash value of the return of GetTypeKey.

◆ IncRef()

void tvm::runtime::Object::IncRef ( )

inlineprotected

developer function, increases reference counter.

◆ IsInstance()

template<typename TargetType >

bool tvm::runtime::Object::IsInstance

inline

Check if the object is an instance of TargetType.

Template Parameters

TargetType The target type to be checked.

Returns: Whether the target type is true.

◆ operator=() [1/2]

Object& tvm::runtime::Object::operator= ( const Object & other )

inline

◆ operator=() [2/2]

Object& tvm::runtime::Object::operator= ( Object && other )

inline

◆ RuntimeTypeIndex()

static uint32_t tvm::runtime::Object::RuntimeTypeIndex ( )

inlinestatic

◆ type_index()

uint32_t tvm::runtime::Object::type_index ( ) const

inline

Returns: The internal runtime type index of the object.

◆ TypeIndex2Key()

static std::string tvm::runtime::Object::TypeIndex2Key ( uint32_t tindex )

static

Get the type key of the corresponding index from runtime.

Parameters

tindex The type index.

Returns: the result.

◆ TypeIndex2KeyHash()

static size_t tvm::runtime::Object::TypeIndex2KeyHash ( uint32_t tindex )

static

Get the type key hash of the corresponding index from runtime.

Parameters

tindex The type index.

Returns: the related key-hash.

◆ TypeKey2Index()

static uint32_t tvm::runtime::Object::TypeKey2Index ( const std::string & key )

static

Get the type index of the corresponding key from runtime.

Parameters

key	The type key.

Returns: the result.

◆ unique()

bool tvm::runtime::Object::unique ( ) const

inline

Returns: Whether the cell has only one reference

Note: We use stl style naming to be consistent with known API in shared_ptr.

Friends And Related Function Documentation

◆ ObjAllocatorBase

template<typename >

friend class ObjAllocatorBase

friend

◆ ObjectInternal

friend class ObjectInternal

friend

◆ ObjectPtr

template<typename >

friend class ObjectPtr

friend

◆ TVMRetValue

friend class TVMRetValue

friend

Member Data Documentation

◆ _type_child_slots

constexpr uint32_t tvm::runtime::Object::_type_child_slots = 0

staticconstexpr

◆ _type_child_slots_can_overflow

constexpr bool tvm::runtime::Object::_type_child_slots_can_overflow = true

staticconstexpr

◆ _type_final

constexpr bool tvm::runtime::Object::_type_final = false

staticconstexpr

◆ _type_has_method_sequal_reduce

constexpr bool tvm::runtime::Object::_type_has_method_sequal_reduce = false

staticconstexpr

◆ _type_has_method_shash_reduce

constexpr bool tvm::runtime::Object::_type_has_method_shash_reduce = false

staticconstexpr

◆ _type_has_method_visit_attrs

constexpr bool tvm::runtime::Object::_type_has_method_visit_attrs = true

staticconstexpr

◆ _type_index

constexpr uint32_t tvm::runtime::Object::_type_index = TypeIndex::kDynamic

staticconstexpr

◆ _type_key

constexpr const char* tvm::runtime::Object::_type_key = "runtime.Object"

staticconstexpr

◆ deleter_

FDeleter tvm::runtime::Object::deleter_ = nullptr

protected

deleter of this object to enable customized allocation. If the deleter is nullptr, no deletion will be performed. The creator of the object must always set the deleter field properly.

◆ ref_counter_

RefCounterType tvm::runtime::Object::ref_counter_ {0}

protected

The internal reference counter.

◆ type_index_

uint32_t tvm::runtime::Object::type_index_ {0}

protected

Type index(tag) that indicates the type of the object.

The documentation for this class was generated from the following file:

include/tvm/runtime/object.h

Public Types

Public Member Functions

Static Public Member Functions

Static Public Attributes

Protected Member Functions

Static Protected Member Functions

Protected Attributes

Friends

Detailed Description

Member Typedef Documentation

◆ FDeleter

◆ RefCounterType

Constructor & Destructor Documentation

◆ Object() [1/3]

◆ Object() [2/3]

◆ Object() [3/3]

Member Function Documentation

◆ _GetOrAllocRuntimeTypeIndex()

◆ DecRef()

◆ GetOrAllocRuntimeTypeIndex()

◆ GetTypeKey()

◆ GetTypeKeyHash()

◆ IncRef()

◆ IsInstance()

◆ operator=() [1/2]

◆ operator=() [2/2]

◆ RuntimeTypeIndex()

◆ type_index()

◆ TypeIndex2Key()

◆ TypeIndex2KeyHash()

◆ TypeKey2Index()

◆ unique()

Friends And Related Function Documentation

◆ ObjAllocatorBase

◆ ObjectInternal

◆ ObjectPtr

◆ TVMRetValue

Member Data Documentation

◆ _type_child_slots

◆ _type_child_slots_can_overflow

◆ _type_final

◆ _type_has_method_sequal_reduce

◆ _type_has_method_shash_reduce

◆ _type_has_method_visit_attrs

◆ _type_index

◆ _type_key

◆ deleter_

◆ ref_counter_

◆ type_index_