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// Copyright 2012 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef V8_EXECUTION_ISOLATE_H_
#define V8_EXECUTION_ISOLATE_H_
#include <atomic>
#include <cstddef>
#include <functional>
#include <memory>
#include <queue>
#include <unordered_map>
#include <vector>
#include "include/v8-context.h"
#include "include/v8-internal.h"
#include "include/v8-isolate.h"
#include "include/v8-metrics.h"
#include "include/v8-snapshot.h"
#include "src/base/macros.h"
#include "src/base/platform/mutex.h"
#include "src/base/platform/platform-posix.h"
#include "src/builtins/builtins.h"
#include "src/common/globals.h"
#include "src/debug/interface-types.h"
#include "src/execution/execution.h"
#include "src/execution/futex-emulation.h"
#include "src/execution/isolate-data.h"
#include "src/execution/messages.h"
#include "src/execution/shared-mutex-guard-if-off-thread.h"
#include "src/execution/stack-guard.h"
#include "src/handles/handles.h"
#include "src/handles/traced-handles.h"
#include "src/heap/base/stack.h"
#include "src/heap/factory.h"
#include "src/heap/heap.h"
#include "src/heap/read-only-heap.h"
#include "src/init/isolate-allocator.h"
#include "src/objects/code.h"
#include "src/objects/contexts.h"
#include "src/objects/debug-objects.h"
#include "src/objects/js-objects.h"
#include "src/runtime/runtime.h"
#include "src/sandbox/external-pointer.h"
#include "src/utils/allocation.h"
#ifdef DEBUG
#include "src/runtime/runtime-utils.h"
#endif
#ifdef V8_INTL_SUPPORT
#include "unicode/uversion.h" // Define U_ICU_NAMESPACE.
namespace U_ICU_NAMESPACE {
class UMemory;
} // namespace U_ICU_NAMESPACE
#endif // V8_INTL_SUPPORT
#if USE_SIMULATOR
#include "src/execution/encoded-c-signature.h"
namespace v8 {
namespace internal {
class SimulatorData;
}
} // namespace v8
#endif
namespace v8_inspector {
class V8Inspector;
} // namespace v8_inspector
namespace v8 {
class EmbedderState;
namespace base {
class RandomNumberGenerator;
} // namespace base
namespace bigint {
class Processor;
}
namespace debug {
class ConsoleDelegate;
class AsyncEventDelegate;
} // namespace debug
namespace internal {
void DefaultWasmAsyncResolvePromiseCallback(
v8::Isolate* isolate, v8::Local<v8::Context> context,
v8::Local<v8::Promise::Resolver> resolver,
v8::Local<v8::Value> compilation_result, WasmAsyncSuccess success);
namespace heap {
class HeapTester;
} // namespace heap
namespace maglev {
class MaglevConcurrentDispatcher;
} // namespace maglev
class AddressToIndexHashMap;
class AstStringConstants;
class Bootstrapper;
class BuiltinsConstantsTableBuilder;
class CancelableTaskManager;
class Logger;
class CodeTracer;
class CommonFrame;
class CompilationCache;
class CompilationStatistics;
class Counters;
class Debug;
class Deoptimizer;
class DescriptorLookupCache;
class EmbeddedFileWriterInterface;
class EternalHandles;
class GlobalHandles;
class GlobalSafepoint;
class HandleScopeImplementer;
class HeapObjectToIndexHashMap;
class HeapProfiler;
class InnerPointerToCodeCache;
class LazyCompileDispatcher;
class LocalIsolate;
class V8FileLogger;
class MaterializedObjectStore;
class Microtask;
class MicrotaskQueue;
class OptimizingCompileDispatcher;
class PersistentHandles;
class PersistentHandlesList;
class ReadOnlyArtifacts;
class RegExpStack;
class RootVisitor;
class SetupIsolateDelegate;
class Simulator;
class SnapshotData;
class StringForwardingTable;
class StringTable;
class StubCache;
class ThreadManager;
class ThreadState;
class ThreadVisitor; // Defined in v8threads.h
class TieringManager;
class TracingCpuProfilerImpl;
class UnicodeCache;
struct ManagedPtrDestructor;
template <StateTag Tag>
class VMState;
namespace baseline {
class BaselineBatchCompiler;
} // namespace baseline
namespace interpreter {
class Interpreter;
} // namespace interpreter
namespace compiler {
class NodeObserver;
class PerIsolateCompilerCache;
} // namespace compiler
namespace win64_unwindinfo {
class BuiltinUnwindInfo;
} // namespace win64_unwindinfo
namespace metrics {
class Recorder;
} // namespace metrics
namespace wasm {
class StackMemory;
}
#define RETURN_FAILURE_IF_SCHEDULED_EXCEPTION(isolate) \
do { \
Isolate* __isolate__ = (isolate); \
DCHECK(!__isolate__->has_pending_exception()); \
if (__isolate__->has_scheduled_exception()) { \
return __isolate__->PromoteScheduledException(); \
} \
} while (false)
#define RETURN_FAILURE_IF_SCHEDULED_EXCEPTION_DETECTOR(isolate, detector) \
do { \
Isolate* __isolate__ = (isolate); \
DCHECK(!__isolate__->has_pending_exception()); \
if (__isolate__->has_scheduled_exception()) { \
detector.AcceptSideEffects(); \
return __isolate__->PromoteScheduledException(); \
} \
} while (false)
// Macros for MaybeHandle.
#define RETURN_VALUE_IF_SCHEDULED_EXCEPTION(isolate, value) \
do { \
Isolate* __isolate__ = (isolate); \
DCHECK(!__isolate__->has_pending_exception()); \
if (__isolate__->has_scheduled_exception()) { \
__isolate__->PromoteScheduledException(); \
return value; \
} \
} while (false)
#define RETURN_VALUE_IF_SCHEDULED_EXCEPTION_DETECTOR(isolate, detector, value) \
RETURN_VALUE_IF_SCHEDULED_EXCEPTION(isolate, \
(detector.AcceptSideEffects(), value))
#define RETURN_EXCEPTION_IF_SCHEDULED_EXCEPTION(isolate, T) \
RETURN_VALUE_IF_SCHEDULED_EXCEPTION(isolate, MaybeHandle<T>())
#define ASSIGN_RETURN_ON_SCHEDULED_EXCEPTION_VALUE(isolate, dst, call, value) \
do { \
Isolate* __isolate__ = (isolate); \
if (!(call).ToLocal(&dst)) { \
DCHECK(__isolate__->has_scheduled_exception()); \
__isolate__->PromoteScheduledException(); \
return value; \
} \
} while (false)
#define RETURN_ON_SCHEDULED_EXCEPTION_VALUE(isolate, call, value) \
do { \
Isolate* __isolate__ = (isolate); \
if ((call).IsNothing()) { \
DCHECK(__isolate__->has_scheduled_exception()); \
__isolate__->PromoteScheduledException(); \
return value; \
} \
} while (false)
/**
* RETURN_RESULT_OR_FAILURE is used in functions with return type Object (such
* as "RUNTIME_FUNCTION(...) {...}" or "BUILTIN(...) {...}" ) to return either
* the contents of a MaybeHandle<X>, or the "exception" sentinel value.
* Example usage:
*
* RUNTIME_FUNCTION(Runtime_Func) {
* ...
* RETURN_RESULT_OR_FAILURE(
* isolate,
* FunctionWithReturnTypeMaybeHandleX(...));
* }
*
* If inside a function with return type MaybeHandle<X> use RETURN_ON_EXCEPTION
* instead.
* If inside a function with return type Handle<X>, or Maybe<X> use
* RETURN_ON_EXCEPTION_VALUE instead.
*/
#define RETURN_RESULT_OR_FAILURE(isolate, call) \
do { \
Handle<Object> __result__; \
Isolate* __isolate__ = (isolate); \
if (!(call).ToHandle(&__result__)) { \
DCHECK(__isolate__->has_pending_exception()); \
return ReadOnlyRoots(__isolate__).exception(); \
} \
DCHECK(!__isolate__->has_pending_exception()); \
return *__result__; \
} while (false)
#define ASSIGN_RETURN_ON_EXCEPTION_VALUE(isolate, dst, call, value) \
do { \
if (!(call).ToHandle(&dst)) { \
DCHECK((isolate)->has_pending_exception()); \
return value; \
} \
} while (false)
#define ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, dst, call) \
do { \
auto* __isolate__ = (isolate); \
ASSIGN_RETURN_ON_EXCEPTION_VALUE(__isolate__, dst, call, \
ReadOnlyRoots(__isolate__).exception()); \
} while (false)
#define ASSIGN_RETURN_ON_EXCEPTION(isolate, dst, call, T) \
ASSIGN_RETURN_ON_EXCEPTION_VALUE(isolate, dst, call, MaybeHandle<T>())
#define THROW_NEW_ERROR(isolate, call, T) \
do { \
auto* __isolate__ = (isolate); \
return __isolate__->template Throw<T>(__isolate__->factory()->call); \
} while (false)
#define THROW_NEW_ERROR_RETURN_FAILURE(isolate, call) \
do { \
auto* __isolate__ = (isolate); \
return __isolate__->Throw(*__isolate__->factory()->call); \
} while (false)
#define THROW_NEW_ERROR_RETURN_VALUE(isolate, call, value) \
do { \
auto* __isolate__ = (isolate); \
__isolate__->Throw(*__isolate__->factory()->call); \
return value; \
} while (false)
/**
* RETURN_ON_EXCEPTION_VALUE conditionally returns the given value when the
* given MaybeHandle is empty. It is typically used in functions with return
* type Maybe<X> or Handle<X>. Example usage:
*
* Handle<X> Func() {
* ...
* RETURN_ON_EXCEPTION_VALUE(
* isolate,
* FunctionWithReturnTypeMaybeHandleX(...),
* Handle<X>());
* // code to handle non exception
* ...
* }
*
* Maybe<bool> Func() {
* ..
* RETURN_ON_EXCEPTION_VALUE(
* isolate,
* FunctionWithReturnTypeMaybeHandleX(...),
* Nothing<bool>);
* // code to handle non exception
* return Just(true);
* }
*
* If inside a function with return type MaybeHandle<X>, use RETURN_ON_EXCEPTION
* instead.
* If inside a function with return type Object, use
* RETURN_FAILURE_ON_EXCEPTION instead.
*/
#define RETURN_ON_EXCEPTION_VALUE(isolate, call, value) \
do { \
if ((call).is_null()) { \
DCHECK((isolate)->has_pending_exception()); \
return value; \
} \
} while (false)
/**
* RETURN_FAILURE_ON_EXCEPTION conditionally returns the "exception" sentinel if
* the given MaybeHandle is empty; so it can only be used in functions with
* return type Object, such as RUNTIME_FUNCTION(...) {...} or BUILTIN(...)
* {...}. Example usage:
*
* RUNTIME_FUNCTION(Runtime_Func) {
* ...
* RETURN_FAILURE_ON_EXCEPTION(
* isolate,
* FunctionWithReturnTypeMaybeHandleX(...));
* // code to handle non exception
* ...
* }
*
* If inside a function with return type MaybeHandle<X>, use RETURN_ON_EXCEPTION
* instead.
* If inside a function with return type Maybe<X> or Handle<X>, use
* RETURN_ON_EXCEPTION_VALUE instead.
*/
#define RETURN_FAILURE_ON_EXCEPTION(isolate, call) \
do { \
Isolate* __isolate__ = (isolate); \
RETURN_ON_EXCEPTION_VALUE(__isolate__, call, \
ReadOnlyRoots(__isolate__).exception()); \
} while (false);
/**
* RETURN_ON_EXCEPTION conditionally returns an empty MaybeHandle<T> if the
* given MaybeHandle is empty. Use it to return immediately from a function with
* return type MaybeHandle when an exception was thrown. Example usage:
*
* MaybeHandle<X> Func() {
* ...
* RETURN_ON_EXCEPTION(
* isolate,
* FunctionWithReturnTypeMaybeHandleY(...),
* X);
* // code to handle non exception
* ...
* }
*
* If inside a function with return type Object, use
* RETURN_FAILURE_ON_EXCEPTION instead.
* If inside a function with return type
* Maybe<X> or Handle<X>, use RETURN_ON_EXCEPTION_VALUE instead.
*/
#define RETURN_ON_EXCEPTION(isolate, call, T) \
RETURN_ON_EXCEPTION_VALUE(isolate, call, MaybeHandle<T>())
#define RETURN_FAILURE(isolate, should_throw, call) \
do { \
if ((should_throw) == kDontThrow) { \
return Just(false); \
} else { \
isolate->Throw(*isolate->factory()->call); \
return Nothing<bool>(); \
} \
} while (false)
#define MAYBE_RETURN(call, value) \
do { \
if ((call).IsNothing()) return value; \
} while (false)
#define MAYBE_RETURN_NULL(call) MAYBE_RETURN(call, MaybeHandle<Object>())
#define MAYBE_RETURN_ON_EXCEPTION_VALUE(isolate, call, value) \
do { \
if ((call).IsNothing()) { \
DCHECK((isolate)->has_pending_exception()); \
return value; \
} \
} while (false)
#define MAYBE_ASSIGN_RETURN_ON_EXCEPTION_VALUE(isolate, dst, call, value) \
do { \
if (!(call).To(&dst)) { \
DCHECK((isolate)->has_pending_exception()); \
return value; \
} \
} while (false)
#define MAYBE_ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, dst, call) \
do { \
Isolate* __isolate__ = (isolate); \
if (!(call).To(&dst)) { \
DCHECK(__isolate__->has_pending_exception()); \
return ReadOnlyRoots(__isolate__).exception(); \
} \
} while (false)
#define FOR_WITH_HANDLE_SCOPE(isolate, loop_var_type, init, loop_var, \
limit_check, increment, body) \
do { \
loop_var_type init; \
loop_var_type for_with_handle_limit = loop_var; \
Isolate* for_with_handle_isolate = isolate; \
while (limit_check) { \
for_with_handle_limit += 1024; \
HandleScope loop_scope(for_with_handle_isolate); \
for (; limit_check && loop_var < for_with_handle_limit; increment) { \
body \
} \
} \
} while (false)
#define WHILE_WITH_HANDLE_SCOPE(isolate, limit_check, body) \
do { \
Isolate* for_with_handle_isolate = isolate; \
while (limit_check) { \
HandleScope loop_scope(for_with_handle_isolate); \
for (int for_with_handle_it = 0; \
limit_check && for_with_handle_it < 1024; ++for_with_handle_it) { \
body \
} \
} \
} while (false)
#define FIELD_ACCESSOR(type, name) \
inline void set_##name(type v) { name##_ = v; } \
inline type name() const { return name##_; }
// Controls for manual embedded blob lifecycle management, used by tests and
// mksnapshot.
V8_EXPORT_PRIVATE void DisableEmbeddedBlobRefcounting();
V8_EXPORT_PRIVATE void FreeCurrentEmbeddedBlob();
#ifdef DEBUG
#define ISOLATE_INIT_DEBUG_ARRAY_LIST(V) \
V(CommentStatistic, paged_space_comments_statistics, \
CommentStatistic::kMaxComments + 1) \
V(int, code_kind_statistics, kCodeKindCount)
#else
#define ISOLATE_INIT_DEBUG_ARRAY_LIST(V)
#endif
#define ISOLATE_INIT_ARRAY_LIST(V) \
/* SerializerDeserializer state. */ \
V(int32_t, jsregexp_static_offsets_vector, kJSRegexpStaticOffsetsVectorSize) \
V(int, bad_char_shift_table, kUC16AlphabetSize) \
V(int, good_suffix_shift_table, (kBMMaxShift + 1)) \
V(int, suffix_table, (kBMMaxShift + 1)) \
ISOLATE_INIT_DEBUG_ARRAY_LIST(V)
using DebugObjectCache = std::vector<Handle<HeapObject>>;
#define ISOLATE_INIT_LIST(V) \
/* Assembler state. */ \
V(FatalErrorCallback, exception_behavior, nullptr) \
V(OOMErrorCallback, oom_behavior, nullptr) \
V(LogEventCallback, event_logger, nullptr) \
V(AllowCodeGenerationFromStringsCallback, allow_code_gen_callback, nullptr) \
V(ModifyCodeGenerationFromStringsCallback, modify_code_gen_callback, \
nullptr) \
V(ModifyCodeGenerationFromStringsCallback2, modify_code_gen_callback2, \
nullptr) \
V(AllowWasmCodeGenerationCallback, allow_wasm_code_gen_callback, nullptr) \
V(ExtensionCallback, wasm_module_callback, &NoExtension) \
V(ExtensionCallback, wasm_instance_callback, &NoExtension) \
V(SharedArrayBufferConstructorEnabledCallback, \
sharedarraybuffer_constructor_enabled_callback, nullptr) \
V(WasmStreamingCallback, wasm_streaming_callback, nullptr) \
V(WasmAsyncResolvePromiseCallback, wasm_async_resolve_promise_callback, \
DefaultWasmAsyncResolvePromiseCallback) \
V(WasmLoadSourceMapCallback, wasm_load_source_map_callback, nullptr) \
V(WasmGCEnabledCallback, wasm_gc_enabled_callback, nullptr) \
/* State for Relocatable. */ \
V(Relocatable*, relocatable_top, nullptr) \
V(DebugObjectCache*, string_stream_debug_object_cache, nullptr) \
V(Object, string_stream_current_security_token, Object()) \
V(const intptr_t*, api_external_references, nullptr) \
V(AddressToIndexHashMap*, external_reference_map, nullptr) \
V(HeapObjectToIndexHashMap*, root_index_map, nullptr) \
V(MicrotaskQueue*, default_microtask_queue, nullptr) \
V(CodeTracer*, code_tracer, nullptr) \
V(PromiseRejectCallback, promise_reject_callback, nullptr) \
V(const v8::StartupData*, snapshot_blob, nullptr) \
V(int, code_and_metadata_size, 0) \
V(int, bytecode_and_metadata_size, 0) \
V(int, external_script_source_size, 0) \
/* Number of CPU profilers running on the isolate. */ \
V(size_t, num_cpu_profilers, 0) \
/* true if a trace is being formatted through Error.prepareStackTrace. */ \
V(bool, formatting_stack_trace, false) \
V(bool, disable_bytecode_flushing, false) \
V(int, last_console_context_id, 0) \
V(v8_inspector::V8Inspector*, inspector, nullptr) \
V(bool, next_v8_call_is_safe_for_termination, false) \
V(bool, only_terminate_in_safe_scope, false) \
V(int, embedder_wrapper_type_index, -1) \
V(int, embedder_wrapper_object_index, -1) \
V(compiler::NodeObserver*, node_observer, nullptr) \
V(bool, javascript_execution_assert, true) \
V(bool, javascript_execution_throws, true) \
V(bool, javascript_execution_dump, true) \
V(uint32_t, javascript_execution_counter, 0) \
V(bool, deoptimization_assert, true) \
V(bool, compilation_assert, true) \
V(bool, no_exception_assert, true)
#define THREAD_LOCAL_TOP_ACCESSOR(type, name) \
inline void set_##name(type v) { thread_local_top()->name##_ = v; } \
inline type name() const { return thread_local_top()->name##_; }
#define THREAD_LOCAL_TOP_ADDRESS(type, name) \
inline type* name##_address() { return &thread_local_top()->name##_; }
// HiddenFactory exists so Isolate can privately inherit from it without making
// Factory's members available to Isolate directly.
class V8_EXPORT_PRIVATE HiddenFactory : private Factory {};
class V8_EXPORT_PRIVATE Isolate final : private HiddenFactory {
// These forward declarations are required to make the friend declarations in
// PerIsolateThreadData work on some older versions of gcc.
class ThreadDataTable;
class EntryStackItem;
public:
Isolate(const Isolate&) = delete;
Isolate& operator=(const Isolate&) = delete;
using HandleScopeType = HandleScope;
void* operator new(size_t) = delete;
void operator delete(void*) = delete;
// A thread has a PerIsolateThreadData instance for each isolate that it has
// entered. That instance is allocated when the isolate is initially entered
// and reused on subsequent entries.
class PerIsolateThreadData {
public:
PerIsolateThreadData(Isolate* isolate, ThreadId thread_id)
: isolate_(isolate),
thread_id_(thread_id),
stack_limit_(0),
thread_state_(nullptr)
#if USE_SIMULATOR
,
simulator_(nullptr)
#endif
{
}
~PerIsolateThreadData();
PerIsolateThreadData(const PerIsolateThreadData&) = delete;
PerIsolateThreadData& operator=(const PerIsolateThreadData&) = delete;
Isolate* isolate() const { return isolate_; }
ThreadId thread_id() const { return thread_id_; }
FIELD_ACCESSOR(uintptr_t, stack_limit)
FIELD_ACCESSOR(ThreadState*, thread_state)
#if USE_SIMULATOR
FIELD_ACCESSOR(Simulator*, simulator)
#endif
bool Matches(Isolate* isolate, ThreadId thread_id) const {
return isolate_ == isolate && thread_id_ == thread_id;
}
private:
Isolate* isolate_;
ThreadId thread_id_;
uintptr_t stack_limit_;
ThreadState* thread_state_;
#if USE_SIMULATOR
Simulator* simulator_;
#endif
friend class Isolate;
friend class ThreadDataTable;
friend class EntryStackItem;
};
static void InitializeOncePerProcess();
// Creates Isolate object. Must be used instead of constructing Isolate with
// new operator.
static Isolate* New();
// Deletes Isolate object. Must be used instead of delete operator.
// Destroys the non-default isolates.
// Sets default isolate into "has_been_disposed" state rather then destroying,
// for legacy API reasons.
static void Delete(Isolate* isolate);
void SetUpFromReadOnlyArtifacts(std::shared_ptr<ReadOnlyArtifacts> artifacts,
ReadOnlyHeap* ro_heap);
void set_read_only_heap(ReadOnlyHeap* ro_heap) { read_only_heap_ = ro_heap; }
// Page allocator that must be used for allocating V8 heap pages.
v8::PageAllocator* page_allocator() const;
// Returns the PerIsolateThreadData for the current thread (or nullptr if one
// is not currently set).
V8_INLINE static PerIsolateThreadData* CurrentPerIsolateThreadData();
// Returns the isolate inside which the current thread is running or nullptr.
V8_INLINE static Isolate* TryGetCurrent();
// Returns the isolate inside which the current thread is running.
V8_INLINE static Isolate* Current();
inline bool IsCurrent() const;
// Usually called by Init(), but can be called early e.g. to allow
// testing components that require logging but not the whole
// isolate.
//
// Safe to call more than once.
void InitializeLoggingAndCounters();
bool InitializeCounters(); // Returns false if already initialized.
bool InitWithoutSnapshot();
bool InitWithSnapshot(SnapshotData* startup_snapshot_data,
SnapshotData* read_only_snapshot_data,
SnapshotData* shared_heap_snapshot_data,
bool can_rehash);
// True if at least one thread Enter'ed this isolate.
bool IsInUse() { return entry_stack_ != nullptr; }
void ReleaseSharedPtrs();
void ClearSerializerData();
void UpdateLogObjectRelocation();
// Initializes the current thread to run this Isolate.
// Not thread-safe. Multiple threads should not Enter/Exit the same isolate
// at the same time, this should be prevented using external locking.
void Enter();
// Exits the current thread. The previously entered Isolate is restored
// for the thread.
// Not thread-safe. Multiple threads should not Enter/Exit the same isolate
// at the same time, this should be prevented using external locking.
void Exit();
// Find the PerThread for this particular (isolate, thread) combination.
// If one does not yet exist, allocate a new one.
PerIsolateThreadData* FindOrAllocatePerThreadDataForThisThread();
// Find the PerThread for this particular (isolate, thread) combination
// If one does not yet exist, return null.
PerIsolateThreadData* FindPerThreadDataForThisThread();
// Find the PerThread for given (isolate, thread) combination
// If one does not yet exist, return null.
PerIsolateThreadData* FindPerThreadDataForThread(ThreadId thread_id);
// Discard the PerThread for this particular (isolate, thread) combination
// If one does not yet exist, no-op.
void DiscardPerThreadDataForThisThread();
// Mutex for serializing access to break control structures.
base::RecursiveMutex* break_access() { return &break_access_; }
// Shared mutex for allowing thread-safe concurrent reads of FeedbackVectors.
base::SharedMutex* feedback_vector_access() {
return &feedback_vector_access_;
}
// Shared mutex for allowing thread-safe concurrent reads of
// InternalizedStrings.
base::SharedMutex* internalized_string_access() {
return &internalized_string_access_;
}
// Shared mutex for allowing thread-safe concurrent reads of TransitionArrays
// of kind kFullTransitionArray.
base::SharedMutex* full_transition_array_access() {
return &full_transition_array_access_;
}
// Shared mutex for allowing thread-safe concurrent reads of
// SharedFunctionInfos.
base::SharedMutex* shared_function_info_access() {
return &shared_function_info_access_;
}
// Protects (most) map update operations, see also MapUpdater.
base::SharedMutex* map_updater_access() { return &map_updater_access_; }
// Protects JSObject boilerplate migrations (i.e. calls to MigrateInstance on
// boilerplate objects; elements kind transitions are *not* protected).
// Note this lock interacts with `map_updater_access` as follows
//
// - boilerplate migrations may trigger map updates.
// - if so, `boilerplate_migration_access` is locked before
// `map_updater_access`.
// - backgrounds threads must use the same lock order to avoid deadlocks.
base::SharedMutex* boilerplate_migration_access() {
return &boilerplate_migration_access_;
}
// The isolate's string table.
StringTable* string_table() const { return string_table_.get(); }
StringForwardingTable* string_forwarding_table() const {
return string_forwarding_table_.get();
}
Address get_address_from_id(IsolateAddressId id);
// Access to top context (where the current function object was created).
Context context() const { return thread_local_top()->context_; }
inline void set_context(Context context);
Context* context_address() { return &thread_local_top()->context_; }
// Access to current thread id.
inline void set_thread_id(ThreadId id) {
thread_local_top()->thread_id_.store(id, std::memory_order_relaxed);
}
inline ThreadId thread_id() const {
return thread_local_top()->thread_id_.load(std::memory_order_relaxed);
}
void InstallConditionalFeatures(Handle<Context> context);
bool IsSharedArrayBufferConstructorEnabled(Handle<Context> context);
bool IsWasmGCEnabled(Handle<Context> context);
bool IsWasmStringRefEnabled(Handle<Context> context);
bool IsWasmInliningEnabled(Handle<Context> context);
THREAD_LOCAL_TOP_ADDRESS(Context, pending_handler_context)
THREAD_LOCAL_TOP_ADDRESS(Address, pending_handler_entrypoint)
THREAD_LOCAL_TOP_ADDRESS(Address, pending_handler_constant_pool)
THREAD_LOCAL_TOP_ADDRESS(Address, pending_handler_fp)
THREAD_LOCAL_TOP_ADDRESS(Address, pending_handler_sp)
THREAD_LOCAL_TOP_ADDRESS(uintptr_t, num_frames_above_pending_handler)
THREAD_LOCAL_TOP_ACCESSOR(bool, external_caught_exception)
v8::TryCatch* try_catch_handler() {
return thread_local_top()->try_catch_handler_;
}
THREAD_LOCAL_TOP_ADDRESS(bool, external_caught_exception)
// Interface to pending exception.
THREAD_LOCAL_TOP_ADDRESS(Object, pending_exception)
inline Object pending_exception();
inline void set_pending_exception(Object exception_obj);
inline void clear_pending_exception();
inline bool has_pending_exception();
THREAD_LOCAL_TOP_ADDRESS(Object, pending_message)
inline void clear_pending_message();
inline Object pending_message();
inline bool has_pending_message();
inline void set_pending_message(Object message_obj);
THREAD_LOCAL_TOP_ADDRESS(Object, scheduled_exception)
inline Object scheduled_exception();
inline bool has_scheduled_exception();
inline void clear_scheduled_exception();
inline void set_scheduled_exception(Object exception);
#ifdef DEBUG
inline Object VerifyBuiltinsResult(Object result);
inline ObjectPair VerifyBuiltinsResult(ObjectPair pair);
#endif
enum class ExceptionHandlerType {
kJavaScriptHandler,
kExternalTryCatch,
kNone
};
ExceptionHandlerType TopExceptionHandlerType(Object exception);
inline bool is_catchable_by_javascript(Object exception);
inline bool is_catchable_by_wasm(Object exception);
inline bool is_execution_terminating();
inline bool is_execution_termination_pending();
// JS execution stack (see frames.h).
static Address c_entry_fp(ThreadLocalTop* thread) {
return thread->c_entry_fp_;
}
static Address handler(ThreadLocalTop* thread) { return thread->handler_; }
Address c_function() { return thread_local_top()->c_function_; }
inline Address* c_entry_fp_address() {
return &thread_local_top()->c_entry_fp_;
}
static uint32_t c_entry_fp_offset() {
return static_cast<uint32_t>(OFFSET_OF(Isolate, isolate_data_) +
OFFSET_OF(IsolateData, thread_local_top_) +
OFFSET_OF(ThreadLocalTop, c_entry_fp_) -
isolate_root_bias());
}
inline Address* handler_address() { return &thread_local_top()->handler_; }
inline Address* c_function_address() {
return &thread_local_top()->c_function_;
}
#if defined(DEBUG) || defined(VERIFY_HEAP)
// Count the number of active deserializers, so that the heap verifier knows
// whether there is currently an active deserialization happening.
//
// This is needed as the verifier currently doesn't support verifying objects
// which are partially deserialized.
//
// TODO(leszeks): Make the verifier a bit more deserialization compatible.
void RegisterDeserializerStarted() { ++num_active_deserializers_; }
void RegisterDeserializerFinished() {
CHECK_GE(--num_active_deserializers_, 0);
}
bool has_active_deserializer() const {
return num_active_deserializers_.load(std::memory_order_acquire) > 0;
}
#else
void RegisterDeserializerStarted() {}
void RegisterDeserializerFinished() {}
bool has_active_deserializer() const { UNREACHABLE(); }
#endif
// Bottom JS entry.
Address js_entry_sp() { return thread_local_top()->js_entry_sp_; }
inline Address* js_entry_sp_address() {
return &thread_local_top()->js_entry_sp_;
}
std::vector<MemoryRange>* GetCodePages() const;
void SetCodePages(std::vector<MemoryRange>* new_code_pages);
// Returns the global object of the current context. It could be
// a builtin object, or a JS global object.
inline Handle<JSGlobalObject> global_object();
// Returns the global proxy object of the current context.
inline Handle<JSGlobalProxy> global_proxy();
static int ArchiveSpacePerThread() { return sizeof(ThreadLocalTop); }
void FreeThreadResources() { thread_local_top()->Free(); }
// This method is called by the api after operations that may throw
// exceptions. If an exception was thrown and not handled by an external
// handler the exception is scheduled to be rethrown when we return to running
// JavaScript code. If an exception is scheduled true is returned.
bool OptionalRescheduleException(bool clear_exception);
// Push and pop a promise and the current try-catch handler.
void PushPromise(Handle<JSObject> promise);
void PopPromise();
bool IsPromiseStackEmpty() const;
// Return the relevant Promise that a throw/rejection pertains to, based
// on the contents of the Promise stack
Handle<Object> GetPromiseOnStackOnThrow();
// Heuristically guess whether a Promise is handled by user catch handler
bool PromiseHasUserDefinedRejectHandler(Handle<JSPromise> promise);
class V8_NODISCARD ExceptionScope {
public:
// Scope currently can only be used for regular exceptions,
// not termination exception.
inline explicit ExceptionScope(Isolate* isolate);
inline ~ExceptionScope();
private:
Isolate* isolate_;
Handle<Object> pending_exception_;
};
void SetCaptureStackTraceForUncaughtExceptions(
bool capture, int frame_limit, StackTrace::StackTraceOptions options);
bool get_capture_stack_trace_for_uncaught_exceptions() const;
void SetAbortOnUncaughtExceptionCallback(
v8::Isolate::AbortOnUncaughtExceptionCallback callback);
enum PrintStackMode { kPrintStackConcise, kPrintStackVerbose };
void PrintCurrentStackTrace(std::ostream& out);
void PrintStack(StringStream* accumulator,
PrintStackMode mode = kPrintStackVerbose);
void PrintStack(FILE* out, PrintStackMode mode = kPrintStackVerbose);
Handle<String> StackTraceString();
// Stores a stack trace in a stack-allocated temporary buffer which will
// end up in the minidump for debugging purposes.
V8_NOINLINE void PushStackTraceAndDie(void* ptr1 = nullptr,
void* ptr2 = nullptr,
void* ptr3 = nullptr,
void* ptr4 = nullptr);
// Similar to the above but without collecting the stack trace.
V8_NOINLINE void PushParamsAndDie(void* ptr1 = nullptr, void* ptr2 = nullptr,
void* ptr3 = nullptr, void* ptr4 = nullptr,
void* ptr5 = nullptr, void* ptr6 = nullptr);
Handle<FixedArray> CaptureDetailedStackTrace(
int limit, StackTrace::StackTraceOptions options);
MaybeHandle<JSObject> CaptureAndSetErrorStack(Handle<JSObject> error_object,
FrameSkipMode mode,
Handle<Object> caller);
Handle<FixedArray> GetDetailedStackTrace(Handle<JSReceiver> error_object);
Handle<FixedArray> GetSimpleStackTrace(Handle<JSReceiver> error_object);
// Walks the JS stack to find the first frame with a script name or
// source URL. The inspected frames are the same as for the detailed stack
// trace.
Handle<String> CurrentScriptNameOrSourceURL();
Address GetAbstractPC(int* line, int* column);
// Returns if the given context may access the given global object. If
// the result is false, the pending exception is guaranteed to be
// set.
bool MayAccess(Handle<Context> accessing_context, Handle<JSObject> receiver);
void SetFailedAccessCheckCallback(v8::FailedAccessCheckCallback callback);
void ReportFailedAccessCheck(Handle<JSObject> receiver);
// Exception throwing support. The caller should use the result
// of Throw() as its return value.
Object Throw(Object exception) { return ThrowInternal(exception, nullptr); }
Object ThrowAt(Handle<JSObject> exception, MessageLocation* location);
Object ThrowIllegalOperation();
template <typename T>
V8_WARN_UNUSED_RESULT MaybeHandle<T> Throw(Handle<Object> exception) {
Throw(*exception);
return MaybeHandle<T>();
}
template <typename T>
V8_WARN_UNUSED_RESULT MaybeHandle<T> ThrowAt(Handle<JSObject> exception,
MessageLocation* location) {
ThrowAt(exception, location);
return MaybeHandle<T>();
}
void FatalProcessOutOfHeapMemory(const char* location) {
heap()->FatalProcessOutOfMemory(location);
}
void set_console_delegate(debug::ConsoleDelegate* delegate) {
console_delegate_ = delegate;
}
debug::ConsoleDelegate* console_delegate() { return console_delegate_; }
void set_async_event_delegate(debug::AsyncEventDelegate* delegate) {
async_event_delegate_ = delegate;
PromiseHookStateUpdated();
}
// Async function and promise instrumentation support.
void OnAsyncFunctionSuspended(Handle<JSPromise> promise,
Handle<JSPromise> parent);
void OnPromiseThen(Handle<JSPromise> promise);
void OnPromiseBefore(Handle<JSPromise> promise);
void OnPromiseAfter(Handle<JSPromise> promise);
void OnTerminationDuringRunMicrotasks();
// Re-throw an exception. This involves no error reporting since error
// reporting was handled when the exception was thrown originally.
// The first overload doesn't set the corresponding pending message, which
// has to be set separately or be guaranteed to not have changed.
Object ReThrow(Object exception);
Object ReThrow(Object exception, Object message);
// Find the correct handler for the current pending exception. This also
// clears and returns the current pending exception.
Object UnwindAndFindHandler();
// Tries to predict whether an exception will be caught. Note that this can
// only produce an estimate, because it is undecidable whether a finally
// clause will consume or re-throw an exception.
enum CatchType {
NOT_CAUGHT,
CAUGHT_BY_JAVASCRIPT,
CAUGHT_BY_EXTERNAL,
CAUGHT_BY_PROMISE,
CAUGHT_BY_ASYNC_AWAIT
};
CatchType PredictExceptionCatcher();
void ScheduleThrow(Object exception);
// Re-set pending message, script and positions reported to the TryCatch
// back to the TLS for re-use when rethrowing.
void RestorePendingMessageFromTryCatch(v8::TryCatch* handler);
// Un-schedule an exception that was caught by a TryCatch handler.
void CancelScheduledExceptionFromTryCatch(v8::TryCatch* handler);
void ReportPendingMessages();
// Promote a scheduled exception to pending. Asserts has_scheduled_exception.
Object PromoteScheduledException();
// Attempts to compute the current source location, storing the
// result in the target out parameter. The source location is attached to a
// Message object as the location which should be shown to the user. It's
// typically the top-most meaningful location on the stack.
bool ComputeLocation(MessageLocation* target);
bool ComputeLocationFromException(MessageLocation* target,
Handle<Object> exception);
bool ComputeLocationFromSimpleStackTrace(MessageLocation* target,
Handle<Object> exception);
bool ComputeLocationFromDetailedStackTrace(MessageLocation* target,
Handle<Object> exception);
Handle<JSMessageObject> CreateMessage(Handle<Object> exception,
MessageLocation* location);
Handle<JSMessageObject> CreateMessageOrAbort(Handle<Object> exception,
MessageLocation* location);
// Similar to Isolate::CreateMessage but DOESN'T inspect the JS stack and
// only looks at the "detailed stack trace" as the "simple stack trace" might
// have already been stringified.
Handle<JSMessageObject> CreateMessageFromException(Handle<Object> exception);
// Out of resource exception helpers.
Object StackOverflow();
Object TerminateExecution();
void CancelTerminateExecution();
void RequestInterrupt(InterruptCallback callback, void* data);
void InvokeApiInterruptCallbacks();
// Administration
void Iterate(RootVisitor* v);
void Iterate(RootVisitor* v, ThreadLocalTop* t);
char* Iterate(RootVisitor* v, char* t);
void IterateThread(ThreadVisitor* v, char* t);
// Returns the current native context.
inline Handle<NativeContext> native_context();
inline NativeContext raw_native_context();
Handle<Context> GetIncumbentContext();
void RegisterTryCatchHandler(v8::TryCatch* that);
void UnregisterTryCatchHandler(v8::TryCatch* that);
char* ArchiveThread(char* to);
char* RestoreThread(char* from);
static const int kUC16AlphabetSize = 256; // See StringSearchBase.
static const int kBMMaxShift = 250; // See StringSearchBase.
// Accessors.
#define GLOBAL_ACCESSOR(type, name, initialvalue) \
inline type name() const { \
DCHECK(OFFSET_OF(Isolate, name##_) == name##_debug_offset_); \
return name##_; \
} \
inline void set_##name(type value) { \
DCHECK(OFFSET_OF(Isolate, name##_) == name##_debug_offset_); \
name##_ = value; \
}
ISOLATE_INIT_LIST(GLOBAL_ACCESSOR)
#undef GLOBAL_ACCESSOR
void SetDetailedSourcePositionsForProfiling(bool value) {
if (value) {
CollectSourcePositionsForAllBytecodeArrays();
}
detailed_source_positions_for_profiling_ = value;
}
bool detailed_source_positions_for_profiling() const {
return detailed_source_positions_for_profiling_;
}
#define GLOBAL_ARRAY_ACCESSOR(type, name, length) \
inline type* name() { \
DCHECK(OFFSET_OF(Isolate, name##_) == name##_debug_offset_); \
return &(name##_)[0]; \
}
ISOLATE_INIT_ARRAY_LIST(GLOBAL_ARRAY_ACCESSOR)
#undef GLOBAL_ARRAY_ACCESSOR
#define NATIVE_CONTEXT_FIELD_ACCESSOR(index, type, name) \
inline Handle<type> name(); \
inline bool is_##name(type value);
NATIVE_CONTEXT_FIELDS(NATIVE_CONTEXT_FIELD_ACCESSOR)
#undef NATIVE_CONTEXT_FIELD_ACCESSOR
Bootstrapper* bootstrapper() { return bootstrapper_; }
// Use for updating counters on a foreground thread.
Counters* counters() { return async_counters().get(); }
// Use for updating counters on a background thread.
const std::shared_ptr<Counters>& async_counters() {
// Make sure InitializeCounters() has been called.
DCHECK_NOT_NULL(async_counters_.get());
return async_counters_;
}
const std::shared_ptr<metrics::Recorder>& metrics_recorder() {
return metrics_recorder_;
}
TieringManager* tiering_manager() { return tiering_manager_; }
CompilationCache* compilation_cache() { return compilation_cache_; }
V8FileLogger* v8_file_logger() const {
// Call InitializeLoggingAndCounters() if logging is needed before
// the isolate is fully initialized.
DCHECK_NOT_NULL(v8_file_logger_);
return v8_file_logger_;
}
StackGuard* stack_guard() { return isolate_data()->stack_guard(); }
Heap* heap() { return &heap_; }
const Heap* heap() const { return &heap_; }
ReadOnlyHeap* read_only_heap() const { return read_only_heap_; }
static Isolate* FromHeap(const Heap* heap) {
return reinterpret_cast<Isolate*>(reinterpret_cast<Address>(heap) -
OFFSET_OF(Isolate, heap_));
}
const IsolateData* isolate_data() const { return &isolate_data_; }
IsolateData* isolate_data() { return &isolate_data_; }
// When pointer compression is on, this is the base address of the pointer
// compression cage, and the kPtrComprCageBaseRegister is set to this
// value. When pointer compression is off, this is always kNullAddress.
Address cage_base() const {
DCHECK_IMPLIES(!COMPRESS_POINTERS_BOOL,
isolate_data()->cage_base() == kNullAddress);
return isolate_data()->cage_base();
}
// When pointer compression and external code space are on, this is the base
// address of the cage where the code space is allocated. Otherwise, it
// defaults to cage_base().
Address code_cage_base() const {
#ifdef V8_EXTERNAL_CODE_SPACE
return code_cage_base_;
#else
return cage_base();
#endif // V8_EXTERNAL_CODE_SPACE
}
// When pointer compression is on, the PtrComprCage used by this
// Isolate. Otherwise nullptr.
VirtualMemoryCage* GetPtrComprCage() {
return isolate_allocator_->GetPtrComprCage();
}
const VirtualMemoryCage* GetPtrComprCage() const {
return isolate_allocator_->GetPtrComprCage();
}
VirtualMemoryCage* GetPtrComprCodeCageForTesting();
// Generated code can embed this address to get access to the isolate-specific
// data (for example, roots, external references, builtins, etc.).
// The kRootRegister is set to this value.
Address isolate_root() const { return isolate_data()->isolate_root(); }
static size_t isolate_root_bias() {
return OFFSET_OF(Isolate, isolate_data_) + IsolateData::kIsolateRootBias;
}
static Isolate* FromRootAddress(Address isolate_root) {
return reinterpret_cast<Isolate*>(isolate_root - isolate_root_bias());
}
RootsTable& roots_table() { return isolate_data()->roots(); }
const RootsTable& roots_table() const { return isolate_data()->roots(); }
// A sub-region of the Isolate object that has "predictable" layout which
// depends only on the pointer size and therefore it's guaranteed that there
// will be no compatibility issues because of different compilers used for
// snapshot generator and actual V8 code.
// Thus, kRootRegister may be used to address any location that falls into
// this region.
// See IsolateData::AssertPredictableLayout() for details.
base::AddressRegion root_register_addressable_region() const {
return base::AddressRegion(reinterpret_cast<Address>(&isolate_data_),
sizeof(IsolateData));
}
Object root(RootIndex index) const { return Object(roots_table()[index]); }
Handle<Object> root_handle(RootIndex index) {
return Handle<Object>(&roots_table()[index]);
}
ExternalReferenceTable* external_reference_table() {
DCHECK(isolate_data()->external_reference_table()->is_initialized());
return isolate_data()->external_reference_table();
}
Address* builtin_entry_table() { return isolate_data_.builtin_entry_table(); }
V8_INLINE Address* builtin_table() { return isolate_data_.builtin_table(); }
V8_INLINE Address* builtin_tier0_table() {
return isolate_data_.builtin_tier0_table();
}
bool IsBuiltinTableHandleLocation(Address* handle_location);
StubCache* load_stub_cache() const { return load_stub_cache_; }
StubCache* store_stub_cache() const { return store_stub_cache_; }
Deoptimizer* GetAndClearCurrentDeoptimizer() {
Deoptimizer* result = current_deoptimizer_;
CHECK_NOT_NULL(result);
current_deoptimizer_ = nullptr;
return result;
}
void set_current_deoptimizer(Deoptimizer* deoptimizer) {
DCHECK_NULL(current_deoptimizer_);
DCHECK_NOT_NULL(deoptimizer);
current_deoptimizer_ = deoptimizer;
}
bool deoptimizer_lazy_throw() const { return deoptimizer_lazy_throw_; }
void set_deoptimizer_lazy_throw(bool value) {
deoptimizer_lazy_throw_ = value;
}
void InitializeThreadLocal();
ThreadLocalTop* thread_local_top() {
return &isolate_data_.thread_local_top_;
}
ThreadLocalTop const* thread_local_top() const {
return &isolate_data_.thread_local_top_;
}
static uint32_t thread_in_wasm_flag_address_offset() {
// For WebAssembly trap handlers there is a flag in thread-local storage
// which indicates that the executing thread executes WebAssembly code. To
// access this flag directly from generated code, we store a pointer to the
// flag in ThreadLocalTop in thread_in_wasm_flag_address_. This function
// here returns the offset of that member from {isolate_root()}.
return static_cast<uint32_t>(
OFFSET_OF(Isolate, isolate_data_) +
OFFSET_OF(IsolateData, thread_local_top_) +
OFFSET_OF(ThreadLocalTop, thread_in_wasm_flag_address_) -
isolate_root_bias());
}
THREAD_LOCAL_TOP_ADDRESS(Address, thread_in_wasm_flag_address)
MaterializedObjectStore* materialized_object_store() const {
return materialized_object_store_;
}
DescriptorLookupCache* descriptor_lookup_cache() const {
return descriptor_lookup_cache_;
}
V8_INLINE HandleScopeData* handle_scope_data() {
return &isolate_data_.handle_scope_data_;
}
HandleScopeImplementer* handle_scope_implementer() const {
DCHECK(handle_scope_implementer_);
return handle_scope_implementer_;
}
UnicodeCache* unicode_cache() const { return unicode_cache_; }
InnerPointerToCodeCache* inner_pointer_to_code_cache() {
return inner_pointer_to_code_cache_;
}
GlobalHandles* global_handles() const { return global_handles_; }
TracedHandles* traced_handles() { return &traced_handles_; }
EternalHandles* eternal_handles() const { return eternal_handles_; }
ThreadManager* thread_manager() const { return thread_manager_; }
bigint::Processor* bigint_processor() { return bigint_processor_; }
#ifndef V8_INTL_SUPPORT
unibrow::Mapping<unibrow::Ecma262UnCanonicalize>* jsregexp_uncanonicalize() {
return &jsregexp_uncanonicalize_;
}
unibrow::Mapping<unibrow::CanonicalizationRange>* jsregexp_canonrange() {
return &jsregexp_canonrange_;
}
unibrow::Mapping<unibrow::Ecma262Canonicalize>*
regexp_macro_assembler_canonicalize() {
return &regexp_macro_assembler_canonicalize_;
}
#endif // !V8_INTL_SUPPORT
RuntimeState* runtime_state() { return &runtime_state_; }
Builtins* builtins() { return &builtins_; }
RegExpStack* regexp_stack() const { return regexp_stack_; }
size_t total_regexp_code_generated() const {
return total_regexp_code_generated_;
}
void IncreaseTotalRegexpCodeGenerated(Handle<HeapObject> code);
std::vector<int>* regexp_indices() { return &regexp_indices_; }
Debug* debug() const { return debug_; }
bool is_profiling() const {
return isolate_data_.execution_mode_ &
IsolateExecutionModeFlag::kIsProfiling;
}
void SetIsProfiling(bool enabled) {
if (enabled) {
CollectSourcePositionsForAllBytecodeArrays();
}
isolate_data_.execution_mode_.set(IsolateExecutionModeFlag::kIsProfiling,
enabled);
UpdateLogObjectRelocation();
}
// Perform side effect checks on function calls and API callbacks.
// See Debug::StartSideEffectCheckMode().
bool should_check_side_effects() const {
return isolate_data_.execution_mode_ &
IsolateExecutionModeFlag::kCheckSideEffects;
}
DebugInfo::ExecutionMode debug_execution_mode() const {
return should_check_side_effects() ? DebugInfo::kSideEffects
: DebugInfo::kBreakpoints;
}
void set_debug_execution_mode(DebugInfo::ExecutionMode debug_execution_mode) {
bool check_side_effects = debug_execution_mode == DebugInfo::kSideEffects;
isolate_data_.execution_mode_.set(
IsolateExecutionModeFlag::kCheckSideEffects, check_side_effects);
}
Logger* logger() const { return logger_; }
HeapProfiler* heap_profiler() const { return heap_profiler_; }
#ifdef DEBUG
static size_t non_disposed_isolates() { return non_disposed_isolates_; }
// Turbofan's string builder optimization can introduce SlicedString that are
// less than SlicedString::kMinLength characters. Their live range and scope
// are pretty limitted, but they can be visible to the GC, which shouldn't
// treat them as invalid. When such short SlicedString are introduced,
// Turbofan will set has_turbofan_string_builders_ to true, which
// SlicedString::SlicedStringVerify will check when verifying SlicedString to
// decide if a too-short SlicedString is an issue or not.
// See the compiler's StringBuilderOptimizer class for more details.
bool has_turbofan_string_builders() { return has_turbofan_string_builders_; }
void set_has_turbofan_string_builders() {
has_turbofan_string_builders_ = true;
}
#endif
v8::internal::Factory* factory() {
// Upcast to the privately inherited base-class using c-style casts to avoid
// undefined behavior (as static_cast cannot cast across private bases).
return (v8::internal::Factory*)this;
}
static const int kJSRegexpStaticOffsetsVectorSize = 128;
THREAD_LOCAL_TOP_ACCESSOR(ExternalCallbackScope*, external_callback_scope)
THREAD_LOCAL_TOP_ACCESSOR(StateTag, current_vm_state)
THREAD_LOCAL_TOP_ACCESSOR(EmbedderState*, current_embedder_state)
void SetData(uint32_t slot, void* data) {
DCHECK_LT(slot, Internals::kNumIsolateDataSlots);
isolate_data_.embedder_data_[slot] = data;
}
void* GetData(uint32_t slot) const {
DCHECK_LT(slot, Internals::kNumIsolateDataSlots);
return isolate_data_.embedder_data_[slot];
}
bool serializer_enabled() const { return serializer_enabled_; }
void enable_serializer() { serializer_enabled_ = true; }
bool snapshot_available() const {
return snapshot_blob_ != nullptr && snapshot_blob_->raw_size != 0;
}
bool IsDead() const { return has_fatal_error_; }
void SignalFatalError() { has_fatal_error_ = true; }
bool use_optimizer();
bool initialized_from_snapshot() { return initialized_from_snapshot_; }
bool NeedsSourcePositions() const;
bool IsLoggingCodeCreation() const;
bool NeedsDetailedOptimizedCodeLineInfo() const;
bool is_best_effort_code_coverage() const {
return code_coverage_mode() == debug::CoverageMode::kBestEffort;
}
bool is_precise_count_code_coverage() const {
return code_coverage_mode() == debug::CoverageMode::kPreciseCount;
}
bool is_precise_binary_code_coverage() const {
return code_coverage_mode() == debug::CoverageMode::kPreciseBinary;
}
bool is_block_count_code_coverage() const {
return code_coverage_mode() == debug::CoverageMode::kBlockCount;
}
bool is_block_binary_code_coverage() const {
return code_coverage_mode() == debug::CoverageMode::kBlockBinary;
}
bool is_block_code_coverage() const {
return is_block_count_code_coverage() || is_block_binary_code_coverage();
}
bool is_binary_code_coverage() const {
return is_precise_binary_code_coverage() || is_block_binary_code_coverage();
}
bool is_count_code_coverage() const {
return is_precise_count_code_coverage() || is_block_count_code_coverage();
}
// Collect feedback vectors with data for code coverage or type profile.
// Reset the list, when both code coverage and type profile are not
// needed anymore. This keeps many feedback vectors alive, but code
// coverage or type profile are used for debugging only and increase in
// memory usage is expected.
void SetFeedbackVectorsForProfilingTools(Object value);
void MaybeInitializeVectorListFromHeap();
double time_millis_since_init() const {
return heap_.MonotonicallyIncreasingTimeInMs() - time_millis_at_init_;
}
DateCache* date_cache() const { return date_cache_; }
void set_date_cache(DateCache* date_cache);
#ifdef V8_INTL_SUPPORT
const std::string& DefaultLocale();
void ResetDefaultLocale();
void set_default_locale(const std::string& locale) {
DCHECK_EQ(default_locale_.length(), 0);
default_locale_ = locale;
}
enum class ICUObjectCacheType{
kDefaultCollator, kDefaultNumberFormat, kDefaultSimpleDateFormat,
kDefaultSimpleDateFormatForTime, kDefaultSimpleDateFormatForDate};
static constexpr int kICUObjectCacheTypeCount = 5;
icu::UMemory* get_cached_icu_object(ICUObjectCacheType cache_type,
Handle<Object> locales);
void set_icu_object_in_cache(ICUObjectCacheType cache_type,
Handle<Object> locales,
std::shared_ptr<icu::UMemory> obj);
void clear_cached_icu_object(ICUObjectCacheType cache_type);
void clear_cached_icu_objects();
#endif // V8_INTL_SUPPORT
enum class KnownPrototype { kNone, kObject, kArray, kString };
KnownPrototype IsArrayOrObjectOrStringPrototype(Object object);
// On intent to set an element in object, make sure that appropriate
// notifications occur if the set is on the elements of the array or
// object prototype. Also ensure that changes to prototype chain between
// Array and Object fire notifications.
void UpdateNoElementsProtectorOnSetElement(Handle<JSObject> object);
void UpdateNoElementsProtectorOnSetLength(Handle<JSObject> object) {
UpdateNoElementsProtectorOnSetElement(object);
}
void UpdateNoElementsProtectorOnSetPrototype(Handle<JSObject> object) {
UpdateNoElementsProtectorOnSetElement(object);
}
void UpdateTypedArraySpeciesLookupChainProtectorOnSetPrototype(
Handle<JSObject> object);
void UpdateNumberStringNotRegexpLikeProtectorOnSetPrototype(
Handle<JSObject> object);
void UpdateNoElementsProtectorOnNormalizeElements(Handle<JSObject> object) {
UpdateNoElementsProtectorOnSetElement(object);
}
// Returns true if array is the initial array prototype in any native context.
inline bool IsAnyInitialArrayPrototype(JSArray array);
std::unique_ptr<PersistentHandles> NewPersistentHandles();
PersistentHandlesList* persistent_handles_list() const {
return persistent_handles_list_.get();
}
#ifdef DEBUG
bool IsDeferredHandle(Address* location);
#endif // DEBUG
baseline::BaselineBatchCompiler* baseline_batch_compiler() const {
DCHECK_NOT_NULL(baseline_batch_compiler_);
return baseline_batch_compiler_;
}
#ifdef V8_ENABLE_MAGLEV
maglev::MaglevConcurrentDispatcher* maglev_concurrent_dispatcher() {
DCHECK_NOT_NULL(maglev_concurrent_dispatcher_);
return maglev_concurrent_dispatcher_;
}
#endif // V8_ENABLE_MAGLEV
bool concurrent_recompilation_enabled() {
// Thread is only available with flag enabled.
DCHECK(optimizing_compile_dispatcher_ == nullptr ||
v8_flags.concurrent_recompilation);
return optimizing_compile_dispatcher_ != nullptr;
}
OptimizingCompileDispatcher* optimizing_compile_dispatcher() {
DCHECK_NOT_NULL(optimizing_compile_dispatcher_);
return optimizing_compile_dispatcher_;
}
// Flushes all pending concurrent optimization jobs from the optimizing
// compile dispatcher's queue.
void AbortConcurrentOptimization(BlockingBehavior blocking_behavior);
int id() const { return id_; }
bool was_locker_ever_used() const {
return was_locker_ever_used_.load(std::memory_order_relaxed);
}
void set_was_locker_ever_used() {
was_locker_ever_used_.store(true, std::memory_order_relaxed);
}
std::shared_ptr<CompilationStatistics> GetTurboStatistics();
CodeTracer* GetCodeTracer();
void DumpAndResetStats();
void* stress_deopt_count_address() { return &stress_deopt_count_; }
void set_force_slow_path(bool v) { force_slow_path_ = v; }
bool force_slow_path() const { return force_slow_path_; }
bool* force_slow_path_address() { return &force_slow_path_; }
bool jitless() const { return jitless_; }
base::RandomNumberGenerator* random_number_generator();
base::RandomNumberGenerator* fuzzer_rng();
// Generates a random number that is non-zero when masked
// with the provided mask.
int GenerateIdentityHash(uint32_t mask);
int NextOptimizationId() {
int id = next_optimization_id_++;
if (!Smi::IsValid(next_optimization_id_)) {
next_optimization_id_ = 0;
}
return id;
}
// https://github.com/tc39/proposal-top-level-await/pull/159
// TODO(syg): Update to actual spec link once merged.
//
// According to the spec, modules that depend on async modules (i.e. modules
// with top-level await) must be evaluated in order in which their
// [[AsyncEvaluating]] flags were set to true. V8 tracks this global total
// order with next_module_async_evaluating_ordinal_. Each module that sets its
// [[AsyncEvaluating]] to true grabs the next ordinal.
unsigned NextModuleAsyncEvaluatingOrdinal() {
unsigned ordinal = next_module_async_evaluating_ordinal_++;
CHECK_LT(ordinal, kMaxModuleAsyncEvaluatingOrdinal);
return ordinal;
}
inline void DidFinishModuleAsyncEvaluation(unsigned ordinal);
void AddNearHeapLimitCallback(v8::NearHeapLimitCallback, void* data);
void RemoveNearHeapLimitCallback(v8::NearHeapLimitCallback callback,
size_t heap_limit);
void AddCallCompletedCallback(CallCompletedCallback callback);
void RemoveCallCompletedCallback(CallCompletedCallback callback);
void FireCallCompletedCallback(MicrotaskQueue* microtask_queue) {
if (!thread_local_top()->CallDepthIsZero()) return;
FireCallCompletedCallbackInternal(microtask_queue);
}
void AddBeforeCallEnteredCallback(BeforeCallEnteredCallback callback);
void RemoveBeforeCallEnteredCallback(BeforeCallEnteredCallback callback);
inline void FireBeforeCallEnteredCallback();
void SetPromiseRejectCallback(PromiseRejectCallback callback);
void ReportPromiseReject(Handle<JSPromise> promise, Handle<Object> value,
v8::PromiseRejectEvent event);
void SetTerminationOnExternalTryCatch();
Handle<Symbol> SymbolFor(RootIndex dictionary_index, Handle<String> name,
bool private_symbol);
void SetUseCounterCallback(v8::Isolate::UseCounterCallback callback);
void CountUsage(v8::Isolate::UseCounterFeature feature);
void CountUsage(v8::Isolate::UseCounterFeature feature, int count);
static std::string GetTurboCfgFileName(Isolate* isolate);
int GetNextScriptId();
#if V8_SFI_HAS_UNIQUE_ID
int GetNextUniqueSharedFunctionInfoId() {
int current_id = next_unique_sfi_id_.load(std::memory_order_relaxed);
int next_id;
do {
if (current_id >= Smi::kMaxValue) {
next_id = 0;
} else {
next_id = current_id + 1;
}
} while (!next_unique_sfi_id_.compare_exchange_weak(
current_id, next_id, std::memory_order_relaxed));
return current_id;
}
#endif
#ifdef V8_ENABLE_JAVASCRIPT_PROMISE_HOOKS
void SetHasContextPromiseHooks(bool context_promise_hook) {
promise_hook_flags_ = PromiseHookFields::HasContextPromiseHook::update(
promise_hook_flags_, context_promise_hook);
PromiseHookStateUpdated();
}
#endif // V8_ENABLE_JAVASCRIPT_PROMISE_HOOKS
bool HasContextPromiseHooks() const {
return PromiseHookFields::HasContextPromiseHook::decode(
promise_hook_flags_);
}
Address promise_hook_flags_address() {
return reinterpret_cast<Address>(&promise_hook_flags_);
}
Address promise_hook_address() {
return reinterpret_cast<Address>(&promise_hook_);
}
Address async_event_delegate_address() {
return reinterpret_cast<Address>(&async_event_delegate_);
}
Address javascript_execution_assert_address() {
return reinterpret_cast<Address>(&javascript_execution_assert_);
}
void IncrementJavascriptExecutionCounter() {
javascript_execution_counter_++;
}
Address handle_scope_implementer_address() {
return reinterpret_cast<Address>(&handle_scope_implementer_);
}
void SetAtomicsWaitCallback(v8::Isolate::AtomicsWaitCallback callback,
void* data);
void RunAtomicsWaitCallback(v8::Isolate::AtomicsWaitEvent event,
Handle<JSArrayBuffer> array_buffer,
size_t offset_in_bytes, int64_t value,
double timeout_in_ms,
AtomicsWaitWakeHandle* stop_handle);
void SetPromiseHook(PromiseHook hook);
void RunPromiseHook(PromiseHookType type, Handle<JSPromise> promise,
Handle<Object> parent);
void RunAllPromiseHooks(PromiseHookType type, Handle<JSPromise> promise,
Handle<Object> parent);
void UpdatePromiseHookProtector();
void PromiseHookStateUpdated();
void AddDetachedContext(Handle<Context> context);
void CheckDetachedContextsAfterGC();
// Detach the environment from its outer global object.
void DetachGlobal(Handle<Context> env);
std::vector<Object>* startup_object_cache() { return &startup_object_cache_; }
// When there is a shared space (i.e. when this is a client Isolate), the
// shared heap object cache holds objects in shared among Isolates. Otherwise
// this object cache is per-Isolate like the startup object cache.
std::vector<Object>* shared_heap_object_cache() {
if (has_shared_space()) {
return &shared_space_isolate()->shared_heap_object_cache_;
}
return &shared_heap_object_cache_;
}
bool IsGeneratingEmbeddedBuiltins() const {
return builtins_constants_table_builder() != nullptr;
}
BuiltinsConstantsTableBuilder* builtins_constants_table_builder() const {
return builtins_constants_table_builder_;
}
// Hashes bits of the Isolate that are relevant for embedded builtins. In
// particular, the embedded blob requires builtin InstructionStream object
// layout and the builtins constants table to remain unchanged from
// build-time.
size_t HashIsolateForEmbeddedBlob();
static const uint8_t* CurrentEmbeddedBlobCode();
static uint32_t CurrentEmbeddedBlobCodeSize();
static const uint8_t* CurrentEmbeddedBlobData();
static uint32_t CurrentEmbeddedBlobDataSize();
static bool CurrentEmbeddedBlobIsBinaryEmbedded();
// These always return the same result as static methods above, but don't
// access the global atomic variable (and thus *might be* slightly faster).
const uint8_t* embedded_blob_code() const;
uint32_t embedded_blob_code_size() const;
const uint8_t* embedded_blob_data() const;
uint32_t embedded_blob_data_size() const;
// Returns true if short builtin calls optimization is enabled for the
// Isolate.
bool is_short_builtin_calls_enabled() const {
return V8_SHORT_BUILTIN_CALLS_BOOL && is_short_builtin_calls_enabled_;
}
// Returns a region from which it's possible to make pc-relative (short)
// calls/jumps to embedded builtins or empty region if there's no embedded
// blob or if pc-relative calls are not supported.
static base::AddressRegion GetShortBuiltinsCallRegion();
void set_array_buffer_allocator(v8::ArrayBuffer::Allocator* allocator) {
array_buffer_allocator_ = allocator;
}
v8::ArrayBuffer::Allocator* array_buffer_allocator() const {
return array_buffer_allocator_;
}
void set_array_buffer_allocator_shared(
std::shared_ptr<v8::ArrayBuffer::Allocator> allocator) {
array_buffer_allocator_shared_ = std::move(allocator);
}
std::shared_ptr<v8::ArrayBuffer::Allocator> array_buffer_allocator_shared()
const {
return array_buffer_allocator_shared_;
}
FutexWaitListNode* futex_wait_list_node() { return &futex_wait_list_node_; }
CancelableTaskManager* cancelable_task_manager() {
return cancelable_task_manager_;
}
const AstStringConstants* ast_string_constants() const {
return ast_string_constants_;
}
interpreter::Interpreter* interpreter() const { return interpreter_; }
compiler::PerIsolateCompilerCache* compiler_cache() const {
return compiler_cache_;
}
void set_compiler_utils(compiler::PerIsolateCompilerCache* cache,
Zone* zone) {
compiler_cache_ = cache;
compiler_zone_ = zone;
}
AccountingAllocator* allocator() { return allocator_; }
LazyCompileDispatcher* lazy_compile_dispatcher() const {
return lazy_compile_dispatcher_.get();
}
bool IsInAnyContext(Object object, uint32_t index);
void ClearKeptObjects();
void SetHostImportModuleDynamicallyCallback(
HostImportModuleDynamicallyWithImportAssertionsCallback callback);
void SetHostImportModuleDynamicallyCallback(
HostImportModuleDynamicallyCallback callback);
MaybeHandle<JSPromise> RunHostImportModuleDynamicallyCallback(
MaybeHandle<Script> maybe_referrer, Handle<Object> specifier,
MaybeHandle<Object> maybe_import_assertions_argument);
void SetHostInitializeImportMetaObjectCallback(
HostInitializeImportMetaObjectCallback callback);
MaybeHandle<JSObject> RunHostInitializeImportMetaObjectCallback(
Handle<SourceTextModule> module);
void SetHostCreateShadowRealmContextCallback(
HostCreateShadowRealmContextCallback callback);
MaybeHandle<NativeContext> RunHostCreateShadowRealmContextCallback();
void RegisterEmbeddedFileWriter(EmbeddedFileWriterInterface* writer) {
embedded_file_writer_ = writer;
}
int LookupOrAddExternallyCompiledFilename(const char* filename);
const char* GetExternallyCompiledFilename(int index) const;
int GetExternallyCompiledFilenameCount() const;
// PrepareBuiltinSourcePositionMap is necessary in order to preserve the
// builtin source positions before the corresponding code objects are
// replaced with trampolines. Those source positions are used to
// annotate the builtin blob with debugging information.
void PrepareBuiltinSourcePositionMap();
// Store the position of the labels that will be used in the list of allowed
// return addresses.
void PrepareBuiltinLabelInfoMap();
#if defined(V8_OS_WIN64)
void SetBuiltinUnwindData(
Builtin builtin,
const win64_unwindinfo::BuiltinUnwindInfo& unwinding_info);
#endif // V8_OS_WIN64
void SetPrepareStackTraceCallback(PrepareStackTraceCallback callback);
MaybeHandle<Object> RunPrepareStackTraceCallback(Handle<Context>,
Handle<JSObject> Error,
Handle<JSArray> sites);
bool HasPrepareStackTraceCallback() const;
void SetAddCrashKeyCallback(AddCrashKeyCallback callback);
void AddCrashKey(CrashKeyId id, const std::string& value) {
if (add_crash_key_callback_) {
add_crash_key_callback_(id, value);
}
}
void SetRAILMode(RAILMode rail_mode);
RAILMode rail_mode() { return rail_mode_.load(); }
void set_code_coverage_mode(debug::CoverageMode coverage_mode) {
code_coverage_mode_.store(coverage_mode, std::memory_order_relaxed);
}
debug::CoverageMode code_coverage_mode() const {
return code_coverage_mode_.load(std::memory_order_relaxed);
}
double LoadStartTimeMs();
void UpdateLoadStartTime();
void IsolateInForegroundNotification();
void IsolateInBackgroundNotification();
bool IsIsolateInBackground() { return is_isolate_in_background_; }
void EnableMemorySavingsMode() { memory_savings_mode_active_ = true; }
void DisableMemorySavingsMode() { memory_savings_mode_active_ = false; }
bool IsMemorySavingsModeActive() { return memory_savings_mode_active_; }
PRINTF_FORMAT(2, 3) void PrintWithTimestamp(const char* format, ...);
void set_allow_atomics_wait(bool set) { allow_atomics_wait_ = set; }
bool allow_atomics_wait() { return allow_atomics_wait_; }
// Register a finalizer to be called at isolate teardown.
void RegisterManagedPtrDestructor(ManagedPtrDestructor* finalizer);
// Removes a previously-registered shared object finalizer.
void UnregisterManagedPtrDestructor(ManagedPtrDestructor* finalizer);
size_t elements_deletion_counter() { return elements_deletion_counter_; }
void set_elements_deletion_counter(size_t value) {
elements_deletion_counter_ = value;
}
#if V8_ENABLE_WEBASSEMBLY
void AddSharedWasmMemory(Handle<WasmMemoryObject> memory_object);
#endif // V8_ENABLE_WEBASSEMBLY
const v8::Context::BackupIncumbentScope* top_backup_incumbent_scope() const {
return top_backup_incumbent_scope_;
}
void set_top_backup_incumbent_scope(
const v8::Context::BackupIncumbentScope* top_backup_incumbent_scope) {
top_backup_incumbent_scope_ = top_backup_incumbent_scope;
}
void SetIdle(bool is_idle);
// Changing various modes can cause differences in generated bytecode which
// interferes with lazy source positions, so this should be called immediately
// before such a mode change to ensure that this cannot happen.
void CollectSourcePositionsForAllBytecodeArrays();
void AddCodeMemoryChunk(MemoryChunk* chunk);
void RemoveCodeMemoryChunk(MemoryChunk* chunk);
void AddCodeRange(Address begin, size_t length_in_bytes);
bool RequiresCodeRange() const;
static Address load_from_stack_count_address(const char* function_name);
static Address store_to_stack_count_address(const char* function_name);
v8::metrics::Recorder::ContextId GetOrRegisterRecorderContextId(
Handle<NativeContext> context);
MaybeLocal<v8::Context> GetContextFromRecorderContextId(
v8::metrics::Recorder::ContextId id);
void UpdateLongTaskStats();
v8::metrics::LongTaskStats* GetCurrentLongTaskStats();
LocalIsolate* main_thread_local_isolate() {
return main_thread_local_isolate_.get();
}
Isolate* AsIsolate() { return this; }
LocalIsolate* AsLocalIsolate() { return main_thread_local_isolate(); }
LocalHeap* main_thread_local_heap();
LocalHeap* CurrentLocalHeap();
#ifdef V8_COMPRESS_POINTERS
ExternalPointerTable& external_pointer_table() {
return isolate_data_.external_pointer_table_;
}
const ExternalPointerTable& external_pointer_table() const {
return isolate_data_.external_pointer_table_;
}
Address external_pointer_table_address() {
return reinterpret_cast<Address>(&isolate_data_.external_pointer_table_);
}
ExternalPointerTable& shared_external_pointer_table() {
return *isolate_data_.shared_external_pointer_table_;
}
const ExternalPointerTable& shared_external_pointer_table() const {
return *isolate_data_.shared_external_pointer_table_;
}
Address shared_external_pointer_table_address_address() {
return reinterpret_cast<Address>(
&isolate_data_.shared_external_pointer_table_);
}
ExternalPointerHandle* GetWaiterQueueNodeExternalPointerHandleLocation() {
return &waiter_queue_node_external_pointer_handle_;
}
ExternalPointerHandle GetOrCreateWaiterQueueNodeExternalPointer();
#endif // V8_COMPRESS_POINTERS
struct PromiseHookFields {
using HasContextPromiseHook = base::BitField<bool, 0, 1>;
using HasIsolatePromiseHook = HasContextPromiseHook::Next<bool, 1>;
using HasAsyncEventDelegate = HasIsolatePromiseHook::Next<bool, 1>;
using IsDebugActive = HasAsyncEventDelegate::Next<bool, 1>;
};
// Returns true when this isolate contains the shared spaces.
bool is_shared_space_isolate() const { return is_shared_space_isolate_; }
// Returns the isolate that owns the shared spaces.
Isolate* shared_space_isolate() const {
DCHECK(has_shared_space());
Isolate* isolate = shared_space_isolate_.value();
DCHECK(has_shared_space());
return isolate;
}
// Returns true when this isolate supports allocation in shared spaces.
bool has_shared_space() const { return shared_space_isolate_.value(); }
GlobalSafepoint* global_safepoint() const { return global_safepoint_.get(); }
bool owns_shareable_data() { return owns_shareable_data_; }
bool log_object_relocation() const { return log_object_relocation_; }
// TODO(pthier): Unify with owns_shareable_data() once the flag
// --shared-string-table is removed.
bool OwnsStringTables() {
return !v8_flags.shared_string_table || is_shared_space_isolate();
}
#if USE_SIMULATOR
SimulatorData* simulator_data() { return simulator_data_; }
#endif
::heap::base::Stack& stack() { return stack_; }
#ifdef V8_ENABLE_WEBASSEMBLY
wasm::StackMemory*& wasm_stacks() { return wasm_stacks_; }
// Update the thread local's Stack object so that it is aware of the new stack
// start and the inactive stacks.
void RecordStackSwitchForScanning();
#endif
// Access to the global "locals block list cache". Caches outer-stack
// allocated variables per ScopeInfo for debug-evaluate.
// We also store a strong reference to the outer ScopeInfo to keep all
// blocklists along a scope chain alive.
void LocalsBlockListCacheSet(Handle<ScopeInfo> scope_info,
Handle<ScopeInfo> outer_scope_info,
Handle<StringSet> locals_blocklist);
// Returns either `TheHole` or `StringSet`.
Object LocalsBlockListCacheGet(Handle<ScopeInfo> scope_info);
void VerifyStaticRoots();
private:
explicit Isolate(std::unique_ptr<IsolateAllocator> isolate_allocator);
~Isolate();
static Isolate* Allocate();
bool Init(SnapshotData* startup_snapshot_data,
SnapshotData* read_only_snapshot_data,
SnapshotData* shared_heap_snapshot_data, bool can_rehash);
void CheckIsolateLayout();
void InitializeCodeRanges();
void AddCodeMemoryRange(MemoryRange range);
static void RemoveContextIdCallback(const v8::WeakCallbackInfo<void>& data);
void FireCallCompletedCallbackInternal(MicrotaskQueue* microtask_queue);
class ThreadDataTable {
public:
ThreadDataTable() = default;
PerIsolateThreadData* Lookup(ThreadId thread_id);
void Insert(PerIsolateThreadData* data);
void Remove(PerIsolateThreadData* data);
void RemoveAllThreads();
private:
struct Hasher {
std::size_t operator()(const ThreadId& t) const {
return std::hash<int>()(t.ToInteger());
}
};
std::unordered_map<ThreadId, PerIsolateThreadData*, Hasher> table_;
};
// These items form a stack synchronously with threads Enter'ing and Exit'ing
// the Isolate. The top of the stack points to a thread which is currently
// running the Isolate. When the stack is empty, the Isolate is considered
// not entered by any thread and can be Disposed.
// If the same thread enters the Isolate more than once, the entry_count_
// is incremented rather then a new item pushed to the stack.
class EntryStackItem {
public:
EntryStackItem(PerIsolateThreadData* previous_thread_data,
Isolate* previous_isolate, EntryStackItem* previous_item)
: entry_count(1),
previous_thread_data(previous_thread_data),
previous_isolate(previous_isolate),
previous_item(previous_item) {}
EntryStackItem(const EntryStackItem&) = delete;
EntryStackItem& operator=(const EntryStackItem&) = delete;
int entry_count;
PerIsolateThreadData* previous_thread_data;
Isolate* previous_isolate;
EntryStackItem* previous_item;
};
static Isolate* process_wide_shared_space_isolate_;
void Deinit();
static void SetIsolateThreadLocals(Isolate* isolate,
PerIsolateThreadData* data);
void FillCache();
// Propagate pending exception message to the v8::TryCatch.
// If there is no external try-catch or message was successfully propagated,
// then return true.
bool PropagatePendingExceptionToExternalTryCatch(
ExceptionHandlerType top_handler);
bool HasIsolatePromiseHooks() const {
return PromiseHookFields::HasIsolatePromiseHook::decode(
promise_hook_flags_);
}
bool HasAsyncEventDelegate() const {
return PromiseHookFields::HasAsyncEventDelegate::decode(
promise_hook_flags_);
}
const char* RAILModeName(RAILMode rail_mode) const {
switch (rail_mode) {
case PERFORMANCE_RESPONSE:
return "RESPONSE";
case PERFORMANCE_ANIMATION:
return "ANIMATION";
case PERFORMANCE_IDLE:
return "IDLE";
case PERFORMANCE_LOAD:
return "LOAD";
}
return "";
}
void AddCrashKeysForIsolateAndHeapPointers();
// Returns the Exception sentinel.
Object ThrowInternal(Object exception, MessageLocation* location);
// This class contains a collection of data accessible from both C++ runtime
// and compiled code (including assembly stubs, builtins, interpreter bytecode
// handlers and optimized code).
IsolateData isolate_data_;
// Set to true if this isolate is used as main isolate with a shared space.
bool is_shared_space_isolate_{false};
std::unique_ptr<IsolateAllocator> isolate_allocator_;
Heap heap_;
ReadOnlyHeap* read_only_heap_ = nullptr;
std::shared_ptr<ReadOnlyArtifacts> artifacts_;
std::shared_ptr<StringTable> string_table_;
std::shared_ptr<StringForwardingTable> string_forwarding_table_;
const int id_;
EntryStackItem* entry_stack_ = nullptr;
int stack_trace_nesting_level_ = 0;
std::atomic<bool> was_locker_ever_used_{false};
StringStream* incomplete_message_ = nullptr;
Address isolate_addresses_[kIsolateAddressCount + 1] = {};
Bootstrapper* bootstrapper_ = nullptr;
TieringManager* tiering_manager_ = nullptr;
CompilationCache* compilation_cache_ = nullptr;
std::shared_ptr<Counters> async_counters_;
base::RecursiveMutex break_access_;
base::SharedMutex feedback_vector_access_;
base::SharedMutex internalized_string_access_;
base::SharedMutex full_transition_array_access_;
base::SharedMutex shared_function_info_access_;
base::SharedMutex map_updater_access_;
base::SharedMutex boilerplate_migration_access_;
V8FileLogger* v8_file_logger_ = nullptr;
StubCache* load_stub_cache_ = nullptr;
StubCache* store_stub_cache_ = nullptr;
Deoptimizer* current_deoptimizer_ = nullptr;
bool deoptimizer_lazy_throw_ = false;
MaterializedObjectStore* materialized_object_store_ = nullptr;
bool capture_stack_trace_for_uncaught_exceptions_ = false;
int stack_trace_for_uncaught_exceptions_frame_limit_ = 0;
StackTrace::StackTraceOptions stack_trace_for_uncaught_exceptions_options_ =
StackTrace::kOverview;
DescriptorLookupCache* descriptor_lookup_cache_ = nullptr;
HandleScopeImplementer* handle_scope_implementer_ = nullptr;
UnicodeCache* unicode_cache_ = nullptr;
AccountingAllocator* allocator_ = nullptr;
InnerPointerToCodeCache* inner_pointer_to_code_cache_ = nullptr;
GlobalHandles* global_handles_ = nullptr;
TracedHandles traced_handles_;
EternalHandles* eternal_handles_ = nullptr;
ThreadManager* thread_manager_ = nullptr;
bigint::Processor* bigint_processor_ = nullptr;
RuntimeState runtime_state_;
Builtins builtins_;
SetupIsolateDelegate* setup_delegate_ = nullptr;
#if defined(DEBUG) || defined(VERIFY_HEAP)
std::atomic<int> num_active_deserializers_;
#endif
#ifndef V8_INTL_SUPPORT
unibrow::Mapping<unibrow::Ecma262UnCanonicalize> jsregexp_uncanonicalize_;
unibrow::Mapping<unibrow::CanonicalizationRange> jsregexp_canonrange_;
unibrow::Mapping<unibrow::Ecma262Canonicalize>
regexp_macro_assembler_canonicalize_;
#endif // !V8_INTL_SUPPORT
RegExpStack* regexp_stack_ = nullptr;
std::vector<int> regexp_indices_;
DateCache* date_cache_ = nullptr;
base::RandomNumberGenerator* random_number_generator_ = nullptr;
base::RandomNumberGenerator* fuzzer_rng_ = nullptr;
std::atomic<RAILMode> rail_mode_;
v8::Isolate::AtomicsWaitCallback atomics_wait_callback_ = nullptr;
void* atomics_wait_callback_data_ = nullptr;
PromiseHook promise_hook_ = nullptr;
HostImportModuleDynamicallyCallback host_import_module_dynamically_callback_ =
nullptr;
HostImportModuleDynamicallyWithImportAssertionsCallback
host_import_module_dynamically_with_import_assertions_callback_ = nullptr;
std::atomic<debug::CoverageMode> code_coverage_mode_{
debug::CoverageMode::kBestEffort};
// Helper function for RunHostImportModuleDynamicallyCallback.
// Unpacks import assertions, if present, from the second argument to dynamic
// import() and returns them in a FixedArray, sorted by code point order of
// the keys, in the form [key1, value1, key2, value2, ...]. Returns an empty
// MaybeHandle if an error was thrown. In this case, the host callback should
// not be called and instead the caller should use the pending exception to
// reject the import() call's Promise.
MaybeHandle<FixedArray> GetImportAssertionsFromArgument(
MaybeHandle<Object> maybe_import_assertions_argument);
HostInitializeImportMetaObjectCallback
host_initialize_import_meta_object_callback_ = nullptr;
HostCreateShadowRealmContextCallback
host_create_shadow_realm_context_callback_ = nullptr;
base::Mutex rail_mutex_;
double load_start_time_ms_ = 0;
#ifdef V8_INTL_SUPPORT
std::string default_locale_;
// The cache stores the most recently accessed {locales,obj} pair for each
// cache type.
struct ICUObjectCacheEntry {
std::string locales;
std::shared_ptr<icu::UMemory> obj;
ICUObjectCacheEntry() = default;
ICUObjectCacheEntry(std::string locales, std::shared_ptr<icu::UMemory> obj)
: locales(locales), obj(std::move(obj)) {}
};
ICUObjectCacheEntry icu_object_cache_[kICUObjectCacheTypeCount];
#endif // V8_INTL_SUPPORT
// Whether the isolate has been created for snapshotting.
bool serializer_enabled_ = false;
// True if fatal error has been signaled for this isolate.
bool has_fatal_error_ = false;
// True if this isolate was initialized from a snapshot.
bool initialized_from_snapshot_ = false;
// True if short builtin calls optimization is enabled.
bool is_short_builtin_calls_enabled_ = false;
// True if the isolate is in background. This flag is used
// to prioritize between memory usage and latency.
bool is_isolate_in_background_ = false;
// True if the isolate is in memory savings mode. This flag is used to
// favor memory over runtime performance.
bool memory_savings_mode_active_ = false;
// Indicates whether the isolate owns shareable data.
// Only false for client isolates attached to a shared isolate.
bool owns_shareable_data_ = true;
bool log_object_relocation_ = false;
#ifdef V8_EXTERNAL_CODE_SPACE
// Base address of the pointer compression cage containing external code
// space, when external code space is enabled.
Address code_cage_base_ = 0;
#endif
// Time stamp at initialization.
double time_millis_at_init_ = 0;
#ifdef DEBUG
static std::atomic<size_t> non_disposed_isolates_;
JSObject::SpillInformation js_spill_information_;
std::atomic<bool> has_turbofan_string_builders_ = false;
#endif
Debug* debug_ = nullptr;
HeapProfiler* heap_profiler_ = nullptr;
Logger* logger_ = nullptr;
const AstStringConstants* ast_string_constants_ = nullptr;
interpreter::Interpreter* interpreter_ = nullptr;
compiler::PerIsolateCompilerCache* compiler_cache_ = nullptr;
// The following zone is for compiler-related objects that should live
// through all compilations (and thus all JSHeapBroker instances).
Zone* compiler_zone_ = nullptr;
std::unique_ptr<LazyCompileDispatcher> lazy_compile_dispatcher_;
baseline::BaselineBatchCompiler* baseline_batch_compiler_ = nullptr;
#ifdef V8_ENABLE_MAGLEV
maglev::MaglevConcurrentDispatcher* maglev_concurrent_dispatcher_ = nullptr;
#endif // V8_ENABLE_MAGLEV
using InterruptEntry = std::pair<InterruptCallback, void*>;
std::queue<InterruptEntry> api_interrupts_queue_;
#define GLOBAL_BACKING_STORE(type, name, initialvalue) type name##_;
ISOLATE_INIT_LIST(GLOBAL_BACKING_STORE)
#undef GLOBAL_BACKING_STORE
#define GLOBAL_ARRAY_BACKING_STORE(type, name, length) type name##_[length];
ISOLATE_INIT_ARRAY_LIST(GLOBAL_ARRAY_BACKING_STORE)
#undef GLOBAL_ARRAY_BACKING_STORE
#ifdef DEBUG
// This class is huge and has a number of fields controlled by
// preprocessor defines. Make sure the offsets of these fields agree
// between compilation units.
#define ISOLATE_FIELD_OFFSET(type, name, ignored) \
static const intptr_t name##_debug_offset_;
ISOLATE_INIT_LIST(ISOLATE_FIELD_OFFSET)
ISOLATE_INIT_ARRAY_LIST(ISOLATE_FIELD_OFFSET)
#undef ISOLATE_FIELD_OFFSET
#endif
bool detailed_source_positions_for_profiling_;
OptimizingCompileDispatcher* optimizing_compile_dispatcher_ = nullptr;
std::unique_ptr<PersistentHandlesList> persistent_handles_list_;
// Counts deopt points if deopt_every_n_times is enabled.
unsigned int stress_deopt_count_ = 0;
bool force_slow_path_ = false;
bool initialized_ = false;
bool jitless_ = false;
int next_optimization_id_ = 0;
#if V8_SFI_HAS_UNIQUE_ID
std::atomic<int> next_unique_sfi_id_;
#endif
unsigned next_module_async_evaluating_ordinal_;
// Vector of callbacks before a Call starts execution.
std::vector<BeforeCallEnteredCallback> before_call_entered_callbacks_;
// Vector of callbacks when a Call completes.
std::vector<CallCompletedCallback> call_completed_callbacks_;
v8::Isolate::UseCounterCallback use_counter_callback_ = nullptr;
std::shared_ptr<CompilationStatistics> turbo_statistics_;
std::shared_ptr<metrics::Recorder> metrics_recorder_;
uintptr_t last_recorder_context_id_ = 0;
std::unordered_map<uintptr_t, v8::Global<v8::Context>>
recorder_context_id_map_;
size_t last_long_task_stats_counter_ = 0;
v8::metrics::LongTaskStats long_task_stats_;
std::vector<Object> startup_object_cache_;
// When sharing data among Isolates (e.g. v8_flags.shared_string_table), only
// the shared Isolate populates this and client Isolates reference that copy.
//
// Otherwise this is populated for all Isolates.
std::vector<Object> shared_heap_object_cache_;
// Used during builtins compilation to build the builtins constants table,
// which is stored on the root list prior to serialization.
BuiltinsConstantsTableBuilder* builtins_constants_table_builder_ = nullptr;
void InitializeDefaultEmbeddedBlob();
void CreateAndSetEmbeddedBlob();
void InitializeIsShortBuiltinCallsEnabled();
void MaybeRemapEmbeddedBuiltinsIntoCodeRange();
void TearDownEmbeddedBlob();
void SetEmbeddedBlob(const uint8_t* code, uint32_t code_size,
const uint8_t* data, uint32_t data_size);
void ClearEmbeddedBlob();
const uint8_t* embedded_blob_code_ = nullptr;
uint32_t embedded_blob_code_size_ = 0;
const uint8_t* embedded_blob_data_ = nullptr;
uint32_t embedded_blob_data_size_ = 0;
v8::ArrayBuffer::Allocator* array_buffer_allocator_ = nullptr;
std::shared_ptr<v8::ArrayBuffer::Allocator> array_buffer_allocator_shared_;
FutexWaitListNode futex_wait_list_node_;
CancelableTaskManager* cancelable_task_manager_ = nullptr;
debug::ConsoleDelegate* console_delegate_ = nullptr;
debug::AsyncEventDelegate* async_event_delegate_ = nullptr;
uint32_t promise_hook_flags_ = 0;
int async_task_count_ = 0;
std::unique_ptr<LocalIsolate> main_thread_local_isolate_;
v8::Isolate::AbortOnUncaughtExceptionCallback
abort_on_uncaught_exception_callback_ = nullptr;
bool allow_atomics_wait_ = true;
base::Mutex managed_ptr_destructors_mutex_;
ManagedPtrDestructor* managed_ptr_destructors_head_ = nullptr;
size_t total_regexp_code_generated_ = 0;
size_t elements_deletion_counter_ = 0;
std::unique_ptr<TracingCpuProfilerImpl> tracing_cpu_profiler_;
EmbeddedFileWriterInterface* embedded_file_writer_ = nullptr;
// The top entry of the v8::Context::BackupIncumbentScope stack.
const v8::Context::BackupIncumbentScope* top_backup_incumbent_scope_ =
nullptr;
PrepareStackTraceCallback prepare_stack_trace_callback_ = nullptr;
// TODO(kenton@cloudflare.com): This mutex can be removed if
// thread_data_table_ is always accessed under the isolate lock. I do not
// know if this is the case, so I'm preserving it for now.
base::Mutex thread_data_table_mutex_;
ThreadDataTable thread_data_table_;
// Stores the isolate containing the shared space.
base::Optional<Isolate*> shared_space_isolate_;
#ifdef V8_COMPRESS_POINTERS
// The external pointer handle to the Isolate's main thread's WaiterQueueNode.
// It is used to wait for JS-exposed mutex or condition variable.
ExternalPointerHandle waiter_queue_node_external_pointer_handle_ =
kNullExternalPointerHandle;
#endif
// Used to track and safepoint all client isolates attached to this shared
// isolate.
std::unique_ptr<GlobalSafepoint> global_safepoint_;
// Client isolates list managed by GlobalSafepoint.
Isolate* global_safepoint_prev_client_isolate_ = nullptr;
Isolate* global_safepoint_next_client_isolate_ = nullptr;
// A signal-safe vector of heap pages containing code. Used with the
// v8::Unwinder API.
std::atomic<std::vector<MemoryRange>*> code_pages_{nullptr};
std::vector<MemoryRange> code_pages_buffer1_;
std::vector<MemoryRange> code_pages_buffer2_;
// The mutex only guards adding pages, the retrieval is signal safe.
base::Mutex code_pages_mutex_;
// Stack information for the main thread.
::heap::base::Stack stack_;
#ifdef V8_ENABLE_WEBASSEMBLY
wasm::StackMemory* wasm_stacks_;
#endif
// Enables the host application to provide a mechanism for recording a
// predefined set of data as crash keys to be used in postmortem debugging
// in case of a crash.
AddCrashKeyCallback add_crash_key_callback_ = nullptr;
// Delete new/delete operators to ensure that Isolate::New() and
// Isolate::Delete() are used for Isolate creation and deletion.
void* operator new(size_t, void* ptr) { return ptr; }
#if USE_SIMULATOR
SimulatorData* simulator_data_ = nullptr;
#endif
friend class heap::HeapTester;
friend class GlobalSafepoint;
friend class TestSerializer;
friend class SharedHeapNoClientsTest;
};
// The current entered Isolate and its thread data. Do not access these
// directly! Use Isolate::Current and Isolate::CurrentPerIsolateThreadData.
//
// These are outside the Isolate class with extern storage because in clang-cl,
// thread_local is incompatible with dllexport linkage caused by
// V8_EXPORT_PRIVATE being applied to Isolate.
extern thread_local Isolate::PerIsolateThreadData*
g_current_per_isolate_thread_data_ V8_CONSTINIT;
extern thread_local Isolate* g_current_isolate_ V8_CONSTINIT;
#undef FIELD_ACCESSOR
#undef THREAD_LOCAL_TOP_ACCESSOR
#undef THREAD_LOCAL_TOP_ADDRESS
// SaveContext scopes save the current context on the Isolate on creation, and
// restore it on destruction.
class V8_EXPORT_PRIVATE SaveContext {
public:
explicit SaveContext(Isolate* isolate);
~SaveContext();
private:
Isolate* const isolate_;
Handle<Context> context_;
};
// Like SaveContext, but also switches the Context to a new one in the
// constructor.
class V8_EXPORT_PRIVATE SaveAndSwitchContext : public SaveContext {
public:
SaveAndSwitchContext(Isolate* isolate, Context new_context);
};
// A scope which sets the given isolate's context to null for its lifetime to
// ensure that code does not make assumptions on a context being available.
class V8_NODISCARD NullContextScope : public SaveAndSwitchContext {
public:
explicit NullContextScope(Isolate* isolate)
: SaveAndSwitchContext(isolate, Context()) {}
};
class AssertNoContextChange {
#ifdef DEBUG
public:
explicit AssertNoContextChange(Isolate* isolate);
~AssertNoContextChange() { DCHECK(isolate_->context() == *context_); }
private:
Isolate* isolate_;
Handle<Context> context_;
#else
public:
explicit AssertNoContextChange(Isolate* isolate) {}
#endif
};
class ExecutionAccess {
public:
explicit ExecutionAccess(Isolate* isolate) : isolate_(isolate) {
Lock(isolate);
}
~ExecutionAccess() { Unlock(isolate_); }
static void Lock(Isolate* isolate) { isolate->break_access()->Lock(); }
static void Unlock(Isolate* isolate) { isolate->break_access()->Unlock(); }
static bool TryLock(Isolate* isolate) {
return isolate->break_access()->TryLock();
}
private:
Isolate* isolate_;
};
// Support for checking for stack-overflows.
class StackLimitCheck {
public:
explicit StackLimitCheck(Isolate* isolate) : isolate_(isolate) {}
// Use this to check for stack-overflows in C++ code.
bool HasOverflowed() const {
StackGuard* stack_guard = isolate_->stack_guard();
return GetCurrentStackPosition() < stack_guard->real_climit();
}
static bool HasOverflowed(LocalIsolate* local_isolate);
// Use this to check for stack-overflow when entering runtime from JS code.
bool JsHasOverflowed(uintptr_t gap = 0) const;
// Use this to check for interrupt request in C++ code.
V8_INLINE bool InterruptRequested() {
StackGuard* stack_guard = isolate_->stack_guard();
return GetCurrentStackPosition() < stack_guard->climit();
}
// Precondition: InterruptRequested == true.
// Returns true if any interrupt (overflow or termination) was handled, in
// which case the caller must prevent further JS execution.
V8_EXPORT_PRIVATE bool HandleStackOverflowAndTerminationRequest();
private:
Isolate* const isolate_;
};
// This macro may be used in context that disallows JS execution.
// That is why it checks only for a stack overflow and termination.
#define STACK_CHECK(isolate, result_value) \
do { \
StackLimitCheck stack_check(isolate); \
if (V8_UNLIKELY(stack_check.InterruptRequested()) && \
V8_UNLIKELY(stack_check.HandleStackOverflowAndTerminationRequest())) { \
return result_value; \
} \
} while (false)
class StackTraceFailureMessage {
public:
enum StackTraceMode { kIncludeStackTrace, kDontIncludeStackTrace };
explicit StackTraceFailureMessage(Isolate* isolate, StackTraceMode mode,
void* ptr1 = nullptr, void* ptr2 = nullptr,
void* ptr3 = nullptr, void* ptr4 = nullptr,
void* ptr5 = nullptr, void* ptr6 = nullptr);
V8_NOINLINE void Print() volatile;
static const uintptr_t kStartMarker = 0xdecade30;
static const uintptr_t kEndMarker = 0xdecade31;
static const int kStacktraceBufferSize = 32 * KB;
uintptr_t start_marker_ = kStartMarker;
void* isolate_;
void* ptr1_;
void* ptr2_;
void* ptr3_;
void* ptr4_;
void* ptr5_;
void* ptr6_;
void* code_objects_[4];
char js_stack_trace_[kStacktraceBufferSize];
uintptr_t end_marker_ = kEndMarker;
};
template <base::MutexSharedType kIsShared>
class V8_NODISCARD SharedMutexGuardIfOffThread<Isolate, kIsShared> final {
public:
SharedMutexGuardIfOffThread(base::SharedMutex* mutex, Isolate* isolate) {
DCHECK_NOT_NULL(mutex);
DCHECK_NOT_NULL(isolate);
DCHECK_EQ(ThreadId::Current(), isolate->thread_id());
}
SharedMutexGuardIfOffThread(const SharedMutexGuardIfOffThread&) = delete;
SharedMutexGuardIfOffThread& operator=(const SharedMutexGuardIfOffThread&) =
delete;
};
} // namespace internal
} // namespace v8
#endif // V8_EXECUTION_ISOLATE_H_