v8::EmbedderRootsHandler Class Reference

#include <v8-embedder-heap.h>

Public Types
enum class	RootHandling { kQueryEmbedderForNonDroppableReferences , kDontQueryEmbedderForAnyReference }

Public Member Functions
virtual	~EmbedderRootsHandler ()=default
	EmbedderRootsHandler ()=default
	EmbedderRootsHandler (RootHandling default_traced_reference_handling)
virtual bool	IsRoot (const v8::TracedReference< v8::Value > &handle)=0
virtual void	ResetRoot (const v8::TracedReference< v8::Value > &handle)=0
virtual bool	TryResetRoot (const v8::TracedReference< v8::Value > &handle)

Friends
class	internal::TracedHandles

Detailed Description

Handler for embedder roots on non-unified heap garbage collections.

Member Enumeration Documentation

RootHandling

enum class v8::EmbedderRootsHandler::RootHandling

strong

Enumerator
kQueryEmbedderForNonDroppableReferences
kDontQueryEmbedderForAnyReference

Constructor & Destructor Documentation

~EmbedderRootsHandler()

virtual v8::EmbedderRootsHandler::~EmbedderRootsHandler ( )

virtualdefault

EmbedderRootsHandler() [1/2]

v8::EmbedderRootsHandler::EmbedderRootsHandler ( )

default

EmbedderRootsHandler() [2/2]

v8::EmbedderRootsHandler::EmbedderRootsHandler ( RootHandling  default_traced_reference_handling )

inlineexplicit

Member Function Documentation

IsRoot()

virtual bool v8::EmbedderRootsHandler::IsRoot ( const v8::TracedReference< v8::Value > &  handle )

pure virtual

Returns true if the |TracedReference| handle should be considered as root for the currently running non-tracing garbage collection and false otherwise. The default implementation will keep all |TracedReference| references as roots.

If this returns false, then V8 may decide that the object referred to by such a handle is reclaimed. In that case, V8 calls |ResetRoot()| for the |TracedReference|.

Note that the handle is different from the handle that the embedder holds for retaining the object.

The concrete implementations must be thread-safe.

ResetRoot()

virtual void v8::EmbedderRootsHandler::ResetRoot ( const v8::TracedReference< v8::Value > &  handle )

pure virtual

Used in combination with |IsRoot|. Called by V8 when an object that is backed by a handle is reclaimed by a non-tracing garbage collection. It is up to the embedder to reset the original handle.

Note that the |handle| is different from the handle that the embedder holds for retaining the object. It is up to the embedder to find the original handle via the object or class id.

TryResetRoot()

virtual bool v8::EmbedderRootsHandler::TryResetRoot ( const v8::TracedReference< v8::Value > &  handle )

inlinevirtual

Similar to |ResetRoot()|, but opportunistic. The function is called in parallel for different handles and as such must be thread-safe. In case, |false| is returned, |ResetRoot()| will be recalled for the same handle.

Friends And Related Function Documentation

internal::TracedHandles

friend class internal::TracedHandles

friend

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

• include/v8-embedder-heap.h