| // Copyright 2011 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. |
| |
| #include "src/objects/contexts.h" |
| |
| #include "src/ast/modules.h" |
| #include "src/debug/debug.h" |
| #include "src/execution/isolate-inl.h" |
| #include "src/init/bootstrapper.h" |
| #include "src/objects/dependent-code.h" |
| #include "src/objects/module-inl.h" |
| #include "src/objects/string-set-inl.h" |
| |
| namespace v8 { |
| namespace internal { |
| |
| // static |
| Handle<ScriptContextTable> ScriptContextTable::New(Isolate* isolate, |
| int capacity, |
| AllocationType allocation) { |
| DCHECK_GE(capacity, 0); |
| DCHECK_LE(capacity, kMaxCapacity); |
| |
| auto names = NameToIndexHashTable::New(isolate, 16); |
| |
| base::Optional<DisallowGarbageCollection> no_gc; |
| Handle<ScriptContextTable> result = |
| Allocate(isolate, capacity, &no_gc, allocation); |
| result->set_length(0, kReleaseStore); |
| result->set_names_to_context_index(*names); |
| ReadOnlyRoots roots{isolate}; |
| MemsetTagged(result->RawFieldOfFirstElement(), roots.undefined_value(), |
| capacity); |
| return result; |
| } |
| |
| namespace { |
| |
| // Adds local names from `script_context` to the hash table. |
| Handle<NameToIndexHashTable> AddLocalNamesFromContext( |
| Isolate* isolate, Handle<NameToIndexHashTable> names_table, |
| Handle<Context> script_context, bool ignore_duplicates, |
| int script_context_index) { |
| ReadOnlyRoots roots(isolate); |
| Handle<ScopeInfo> scope_info(script_context->scope_info(), isolate); |
| int local_count = scope_info->ContextLocalCount(); |
| names_table = names_table->EnsureCapacity(isolate, names_table, local_count); |
| |
| for (auto it : ScopeInfo::IterateLocalNames(scope_info)) { |
| Handle<Name> name(it->name(), isolate); |
| if (ignore_duplicates) { |
| int32_t hash = NameToIndexShape::Hash(roots, name); |
| if (names_table->FindEntry(isolate, roots, name, hash).is_found()) { |
| continue; |
| } |
| } |
| names_table = NameToIndexHashTable::Add(isolate, names_table, name, |
| script_context_index); |
| } |
| |
| return names_table; |
| } |
| |
| } // namespace |
| |
| Handle<ScriptContextTable> ScriptContextTable::Add( |
| Isolate* isolate, Handle<ScriptContextTable> table, |
| Handle<Context> script_context, bool ignore_duplicates) { |
| DCHECK(script_context->IsScriptContext()); |
| |
| int old_length = table->length(kAcquireLoad); |
| int new_length = old_length + 1; |
| DCHECK_LE(0, old_length); |
| |
| Handle<ScriptContextTable> result = table; |
| int old_capacity = table->capacity(); |
| DCHECK_LE(old_length, old_capacity); |
| if (old_length == old_capacity) { |
| int new_capacity = NewCapacityForIndex(old_length, old_capacity); |
| auto new_table = New(isolate, new_capacity); |
| new_table->set_length(old_length, kReleaseStore); |
| new_table->set_names_to_context_index(table->names_to_context_index()); |
| CopyElements(isolate, *new_table, 0, *table, 0, old_length); |
| result = new_table; |
| } |
| |
| Handle<NameToIndexHashTable> names_table(result->names_to_context_index(), |
| isolate); |
| names_table = AddLocalNamesFromContext(isolate, names_table, script_context, |
| ignore_duplicates, old_length); |
| result->set_names_to_context_index(*names_table); |
| |
| result->set(old_length, *script_context, kReleaseStore); |
| result->set_length(new_length, kReleaseStore); |
| return result; |
| } |
| |
| void Context::Initialize(Isolate* isolate) { |
| Tagged<ScopeInfo> scope_info = this->scope_info(); |
| int header = scope_info->ContextHeaderLength(); |
| for (int var = 0; var < scope_info->ContextLocalCount(); var++) { |
| if (scope_info->ContextLocalInitFlag(var) == kNeedsInitialization) { |
| set(header + var, ReadOnlyRoots(isolate).the_hole_value()); |
| } |
| } |
| } |
| |
| bool ScriptContextTable::Lookup(Handle<String> name, |
| VariableLookupResult* result) { |
| DisallowGarbageCollection no_gc; |
| int index = names_to_context_index()->Lookup(name); |
| if (index == -1) return false; |
| DCHECK_LE(0, index); |
| DCHECK_LT(index, length(kAcquireLoad)); |
| Tagged<Context> context = get(index); |
| DCHECK(context->IsScriptContext()); |
| int slot_index = context->scope_info()->ContextSlotIndex(name, result); |
| if (slot_index < 0) return false; |
| result->context_index = index; |
| result->slot_index = slot_index; |
| return true; |
| } |
| |
| bool Context::is_declaration_context() const { |
| if (IsFunctionContext() || IsNativeContext(*this) || IsScriptContext() || |
| IsModuleContext()) { |
| return true; |
| } |
| if (IsEvalContext()) { |
| return scope_info()->language_mode() == LanguageMode::kStrict; |
| } |
| if (!IsBlockContext()) return false; |
| return scope_info()->is_declaration_scope(); |
| } |
| |
| Tagged<Context> Context::declaration_context() const { |
| Tagged<Context> current = *this; |
| while (!current->is_declaration_context()) { |
| current = current->previous(); |
| } |
| return current; |
| } |
| |
| Tagged<Context> Context::closure_context() const { |
| Tagged<Context> current = *this; |
| while (!current->IsFunctionContext() && !current->IsScriptContext() && |
| !current->IsModuleContext() && !IsNativeContext(current) && |
| !current->IsEvalContext()) { |
| current = current->previous(); |
| } |
| return current; |
| } |
| |
| Tagged<JSObject> Context::extension_object() const { |
| DCHECK(IsNativeContext(*this) || IsFunctionContext() || IsBlockContext() || |
| IsEvalContext() || IsCatchContext()); |
| Tagged<HeapObject> object = extension(); |
| if (IsUndefined(object)) return JSObject(); |
| DCHECK(IsJSContextExtensionObject(object) || |
| (IsNativeContext(*this) && IsJSGlobalObject(object))); |
| return JSObject::cast(object); |
| } |
| |
| Tagged<JSReceiver> Context::extension_receiver() const { |
| DCHECK(IsNativeContext(*this) || IsWithContext() || IsEvalContext() || |
| IsFunctionContext() || IsBlockContext()); |
| return IsWithContext() ? JSReceiver::cast(extension()) : extension_object(); |
| } |
| |
| Tagged<SourceTextModule> Context::module() const { |
| Tagged<Context> current = *this; |
| while (!current->IsModuleContext()) { |
| current = current->previous(); |
| } |
| return SourceTextModule::cast(current->extension()); |
| } |
| |
| Tagged<JSGlobalObject> Context::global_object() const { |
| return JSGlobalObject::cast(native_context()->extension()); |
| } |
| |
| Tagged<Context> Context::script_context() const { |
| Tagged<Context> current = *this; |
| while (!current->IsScriptContext()) { |
| current = current->previous(); |
| } |
| return current; |
| } |
| |
| Tagged<JSGlobalProxy> Context::global_proxy() const { |
| return native_context()->global_proxy_object(); |
| } |
| |
| /** |
| * Lookups a property in an object environment, taking the unscopables into |
| * account. This is used For HasBinding spec algorithms for ObjectEnvironment. |
| */ |
| static Maybe<bool> UnscopableLookup(LookupIterator* it, bool is_with_context) { |
| Isolate* isolate = it->isolate(); |
| |
| Maybe<bool> found = JSReceiver::HasProperty(it); |
| if (!is_with_context || found.IsNothing() || !found.FromJust()) return found; |
| |
| Handle<Object> unscopables; |
| ASSIGN_RETURN_ON_EXCEPTION_VALUE( |
| isolate, unscopables, |
| JSReceiver::GetProperty(isolate, |
| Handle<JSReceiver>::cast(it->GetReceiver()), |
| isolate->factory()->unscopables_symbol()), |
| Nothing<bool>()); |
| if (!IsJSReceiver(*unscopables)) return Just(true); |
| Handle<Object> blocklist; |
| ASSIGN_RETURN_ON_EXCEPTION_VALUE( |
| isolate, blocklist, |
| JSReceiver::GetProperty(isolate, Handle<JSReceiver>::cast(unscopables), |
| it->name()), |
| Nothing<bool>()); |
| return Just(!Object::BooleanValue(*blocklist, isolate)); |
| } |
| |
| static PropertyAttributes GetAttributesForMode(VariableMode mode) { |
| DCHECK(IsSerializableVariableMode(mode)); |
| return IsImmutableLexicalOrPrivateVariableMode(mode) ? READ_ONLY : NONE; |
| } |
| |
| // static |
| Handle<Object> Context::Lookup(Handle<Context> context, Handle<String> name, |
| ContextLookupFlags flags, int* index, |
| PropertyAttributes* attributes, |
| InitializationFlag* init_flag, |
| VariableMode* variable_mode, |
| bool* is_sloppy_function_name) { |
| Isolate* isolate = context->GetIsolate(); |
| |
| bool follow_context_chain = (flags & FOLLOW_CONTEXT_CHAIN) != 0; |
| bool has_seen_debug_evaluate_context = false; |
| *index = kNotFound; |
| *attributes = ABSENT; |
| *init_flag = kCreatedInitialized; |
| *variable_mode = VariableMode::kVar; |
| if (is_sloppy_function_name != nullptr) { |
| *is_sloppy_function_name = false; |
| } |
| |
| if (v8_flags.trace_contexts) { |
| PrintF("Context::Lookup("); |
| ShortPrint(*name); |
| PrintF(")\n"); |
| } |
| |
| do { |
| if (v8_flags.trace_contexts) { |
| PrintF(" - looking in context %p", |
| reinterpret_cast<void*>(context->ptr())); |
| if (context->IsScriptContext()) PrintF(" (script context)"); |
| if (IsNativeContext(*context)) PrintF(" (native context)"); |
| if (context->IsDebugEvaluateContext()) PrintF(" (debug context)"); |
| PrintF("\n"); |
| } |
| |
| // 1. Check global objects, subjects of with, and extension objects. |
| DCHECK_IMPLIES(context->IsEvalContext() && context->has_extension(), |
| IsTheHole(context->extension(), isolate)); |
| if ((IsNativeContext(*context) || context->IsWithContext() || |
| context->IsFunctionContext() || context->IsBlockContext()) && |
| context->has_extension() && !context->extension_receiver().is_null()) { |
| Handle<JSReceiver> object(context->extension_receiver(), isolate); |
| |
| if (IsNativeContext(*context)) { |
| DisallowGarbageCollection no_gc; |
| if (v8_flags.trace_contexts) { |
| PrintF(" - trying other script contexts\n"); |
| } |
| // Try other script contexts. |
| Tagged<ScriptContextTable> script_contexts = |
| context->native_context()->script_context_table(); |
| VariableLookupResult r; |
| if (script_contexts->Lookup(name, &r)) { |
| Tagged<Context> script_context = |
| script_contexts->get(r.context_index); |
| if (v8_flags.trace_contexts) { |
| PrintF("=> found property in script context %d: %p\n", |
| r.context_index, |
| reinterpret_cast<void*>(script_context.ptr())); |
| } |
| *index = r.slot_index; |
| *variable_mode = r.mode; |
| *init_flag = r.init_flag; |
| *attributes = GetAttributesForMode(r.mode); |
| return handle(script_context, isolate); |
| } |
| } |
| |
| // Context extension objects needs to behave as if they have no |
| // prototype. So even if we want to follow prototype chains, we need |
| // to only do a local lookup for context extension objects. |
| Maybe<PropertyAttributes> maybe = Nothing<PropertyAttributes>(); |
| if ((flags & FOLLOW_PROTOTYPE_CHAIN) == 0 || |
| IsJSContextExtensionObject(*object)) { |
| maybe = JSReceiver::GetOwnPropertyAttributes(object, name); |
| } else { |
| // A with context will never bind "this", but debug-eval may look into |
| // a with context when resolving "this". Other synthetic variables such |
| // as new.target may be resolved as VariableMode::kDynamicLocal due to |
| // bug v8:5405 , skipping them here serves as a workaround until a more |
| // thorough fix can be applied. |
| // TODO(v8:5405): Replace this check with a DCHECK when resolution of |
| // of synthetic variables does not go through this code path. |
| if (ScopeInfo::VariableIsSynthetic(*name)) { |
| maybe = Just(ABSENT); |
| } else { |
| LookupIterator it(isolate, object, name, object); |
| Maybe<bool> found = UnscopableLookup(&it, context->IsWithContext()); |
| if (found.IsNothing()) { |
| maybe = Nothing<PropertyAttributes>(); |
| } else { |
| // Luckily, consumers of |maybe| only care whether the property |
| // was absent or not, so we can return a dummy |NONE| value |
| // for its attributes when it was present. |
| maybe = Just(found.FromJust() ? NONE : ABSENT); |
| } |
| } |
| } |
| |
| if (maybe.IsNothing()) return Handle<Object>(); |
| DCHECK(!isolate->has_exception()); |
| *attributes = maybe.FromJust(); |
| |
| if (maybe.FromJust() != ABSENT) { |
| if (v8_flags.trace_contexts) { |
| PrintF("=> found property in context object %p\n", |
| reinterpret_cast<void*>(object->ptr())); |
| } |
| return object; |
| } |
| } |
| |
| // 2. Check the context proper if it has slots. |
| if (context->IsFunctionContext() || context->IsBlockContext() || |
| context->IsScriptContext() || context->IsEvalContext() || |
| context->IsModuleContext() || context->IsCatchContext()) { |
| DisallowGarbageCollection no_gc; |
| // Use serialized scope information of functions and blocks to search |
| // for the context index. |
| Tagged<ScopeInfo> scope_info = context->scope_info(); |
| VariableLookupResult lookup_result; |
| int slot_index = scope_info->ContextSlotIndex(name, &lookup_result); |
| DCHECK(slot_index < 0 || slot_index >= MIN_CONTEXT_SLOTS); |
| if (slot_index >= 0) { |
| // Re-direct lookup to the ScriptContextTable in case we find a hole in |
| // a REPL script context. REPL scripts allow re-declaration of |
| // script-level let bindings. The value itself is stored in the script |
| // context of the first script that declared a variable, all other |
| // script contexts will contain 'the hole' for that particular name. |
| if (scope_info->IsReplModeScope() && |
| IsTheHole(context->get(slot_index), isolate)) { |
| context = Handle<Context>(context->previous(), isolate); |
| continue; |
| } |
| |
| if (v8_flags.trace_contexts) { |
| PrintF("=> found local in context slot %d (mode = %hhu)\n", |
| slot_index, static_cast<uint8_t>(lookup_result.mode)); |
| } |
| *index = slot_index; |
| *variable_mode = lookup_result.mode; |
| *init_flag = lookup_result.init_flag; |
| *attributes = GetAttributesForMode(lookup_result.mode); |
| return context; |
| } |
| |
| // Check the slot corresponding to the intermediate context holding |
| // only the function name variable. It's conceptually (and spec-wise) |
| // in an outer scope of the function's declaration scope. |
| if (follow_context_chain && context->IsFunctionContext()) { |
| int function_index = scope_info->FunctionContextSlotIndex(*name); |
| if (function_index >= 0) { |
| if (v8_flags.trace_contexts) { |
| PrintF("=> found intermediate function in context slot %d\n", |
| function_index); |
| } |
| *index = function_index; |
| *attributes = READ_ONLY; |
| *init_flag = kCreatedInitialized; |
| *variable_mode = VariableMode::kConst; |
| if (is_sloppy_function_name != nullptr && |
| is_sloppy(scope_info->language_mode())) { |
| *is_sloppy_function_name = true; |
| } |
| return context; |
| } |
| } |
| |
| // Lookup variable in module imports and exports. |
| if (context->IsModuleContext()) { |
| VariableMode mode; |
| InitializationFlag flag; |
| MaybeAssignedFlag maybe_assigned_flag; |
| int cell_index = |
| scope_info->ModuleIndex(*name, &mode, &flag, &maybe_assigned_flag); |
| if (cell_index != 0) { |
| if (v8_flags.trace_contexts) { |
| PrintF("=> found in module imports or exports\n"); |
| } |
| *index = cell_index; |
| *variable_mode = mode; |
| *init_flag = flag; |
| *attributes = SourceTextModuleDescriptor::GetCellIndexKind( |
| cell_index) == SourceTextModuleDescriptor::kExport |
| ? GetAttributesForMode(mode) |
| : READ_ONLY; |
| return handle(context->module(), isolate); |
| } |
| } |
| } else if (context->IsDebugEvaluateContext()) { |
| has_seen_debug_evaluate_context = true; |
| |
| // Check materialized locals. |
| Tagged<Object> ext = context->get(EXTENSION_INDEX); |
| if (IsJSReceiver(ext)) { |
| Handle<JSReceiver> extension(JSReceiver::cast(ext), isolate); |
| LookupIterator it(isolate, extension, name, extension); |
| Maybe<bool> found = JSReceiver::HasProperty(&it); |
| if (found.FromMaybe(false)) { |
| *attributes = NONE; |
| return extension; |
| } |
| } |
| |
| // Check the original context, but do not follow its context chain. |
| Tagged<Object> obj = context->get(WRAPPED_CONTEXT_INDEX); |
| if (IsContext(obj)) { |
| Handle<Context> wrapped_context(Context::cast(obj), isolate); |
| Handle<Object> result = |
| Context::Lookup(wrapped_context, name, DONT_FOLLOW_CHAINS, index, |
| attributes, init_flag, variable_mode); |
| if (!result.is_null()) return result; |
| } |
| } |
| |
| // 3. Prepare to continue with the previous (next outermost) context. |
| if (IsNativeContext(*context)) break; |
| |
| // In case we saw any DebugEvaluateContext, we'll need to check the block |
| // list before we can advance to properly "shadow" stack-allocated |
| // variables. |
| // Note that this implicitly skips the block list check for the |
| // "wrapped" context lookup for DebugEvaluateContexts. In that case |
| // `has_seen_debug_evaluate_context` will always be false. |
| if (has_seen_debug_evaluate_context && |
| IsEphemeronHashTable(isolate->heap()->locals_block_list_cache())) { |
| Handle<ScopeInfo> scope_info = handle(context->scope_info(), isolate); |
| Tagged<Object> maybe_outer_block_list = |
| isolate->LocalsBlockListCacheGet(scope_info); |
| if (IsStringSet(maybe_outer_block_list) && |
| StringSet::cast(maybe_outer_block_list)->Has(isolate, name)) { |
| if (v8_flags.trace_contexts) { |
| PrintF(" - name is blocklisted. Aborting.\n"); |
| } |
| break; |
| } |
| } |
| |
| context = Handle<Context>(context->previous(), isolate); |
| } while (follow_context_chain); |
| |
| if (v8_flags.trace_contexts) { |
| PrintF("=> no property/slot found\n"); |
| } |
| return Handle<Object>::null(); |
| } |
| |
| Tagged<ConstTrackingLetCell> Context::GetOrCreateConstTrackingLetCell( |
| Handle<Context> script_context, size_t index, Isolate* isolate) { |
| DCHECK(v8_flags.const_tracking_let); |
| DCHECK(script_context->IsScriptContext()); |
| int side_data_index = |
| static_cast<int>(index - Context::MIN_CONTEXT_EXTENDED_SLOTS); |
| Handle<FixedArray> side_data = handle( |
| FixedArray::cast(script_context->get(CONST_TRACKING_LET_SIDE_DATA_INDEX)), |
| isolate); |
| Tagged<Object> object = side_data->get(side_data_index); |
| if (!IsConstTrackingLetCell(object)) { |
| // If these CHECKs fail, there's a code path which initializes or assigns a |
| // top-level `let` variable but doesn't update the side data. |
| CHECK_EQ(object, ConstTrackingLetCell::kConstMarker); |
| object = *isolate->factory()->NewConstTrackingLetCell(); |
| side_data->set(side_data_index, object); |
| } |
| return ConstTrackingLetCell::cast(object); |
| } |
| |
| bool Context::ConstTrackingLetSideDataIsConst(size_t index) const { |
| DCHECK(v8_flags.const_tracking_let); |
| DCHECK(IsScriptContext()); |
| int side_data_index = |
| static_cast<int>(index - Context::MIN_CONTEXT_EXTENDED_SLOTS); |
| Tagged<FixedArray> side_data = |
| FixedArray::cast(get(CONST_TRACKING_LET_SIDE_DATA_INDEX)); |
| Tagged<Object> object = side_data->get(side_data_index); |
| return !ConstTrackingLetCell::IsNotConst(object); |
| } |
| |
| void Context::UpdateConstTrackingLetSideData(Handle<Context> script_context, |
| int index, |
| Handle<Object> new_value, |
| Isolate* isolate) { |
| DCHECK(v8_flags.const_tracking_let); |
| DCHECK(script_context->IsScriptContext()); |
| Handle<Object> old_value = handle(script_context->get(index), isolate); |
| const int side_data_index = index - Context::MIN_CONTEXT_EXTENDED_SLOTS; |
| Handle<FixedArray> side_data = handle( |
| FixedArray::cast( |
| script_context->get(Context::CONST_TRACKING_LET_SIDE_DATA_INDEX)), |
| isolate); |
| if (IsTheHole(*old_value)) { |
| // Setting the initial value. Here we cannot assert the corresponding side |
| // data is `undefined` - that won't hold w/ variable redefinitions in REPL. |
| side_data->set(side_data_index, ConstTrackingLetCell::kConstMarker); |
| return; |
| } |
| if (*old_value == *new_value) { |
| return; |
| } |
| // From now on, we know the value is no longer a constant. If there's a |
| // DependentCode, invalidate it. |
| Tagged<Object> data = side_data->get(side_data_index); |
| if (IsConstTrackingLetCell(data)) { |
| DependentCode::DeoptimizeDependencyGroups( |
| isolate, ConstTrackingLetCell::cast(data), |
| DependentCode::kConstTrackingLetChangedGroup); |
| } else { |
| // The value is not constant, but it also was not used as a constant |
| // (there's no code to invalidate). No action needed here; the data will |
| // be updated below. |
| |
| // If the CHECK fails, there's a code path which initializes or assigns a |
| // top-level `let` variable but doesn't update the side data. |
| CHECK(IsSmi(data)); |
| } |
| side_data->set(side_data_index, ConstTrackingLetCell::kNonConstMarker); |
| } |
| |
| bool NativeContext::HasTemplateLiteralObject(Tagged<JSArray> array) { |
| return array->map() == js_array_template_literal_object_map(); |
| } |
| |
| Handle<Object> Context::ErrorMessageForCodeGenerationFromStrings() { |
| Isolate* isolate = GetIsolate(); |
| Handle<Object> result(error_message_for_code_gen_from_strings(), isolate); |
| if (!IsUndefined(*result, isolate)) return result; |
| return isolate->factory()->NewStringFromStaticChars( |
| "Code generation from strings disallowed for this context"); |
| } |
| |
| Handle<Object> Context::ErrorMessageForWasmCodeGeneration() { |
| Isolate* isolate = GetIsolate(); |
| Handle<Object> result(error_message_for_wasm_code_gen(), isolate); |
| if (!IsUndefined(*result, isolate)) return result; |
| return isolate->factory()->NewStringFromStaticChars( |
| "Wasm code generation disallowed by embedder"); |
| } |
| |
| #define COMPARE_NAME(index, type, name) \ |
| if (string->IsOneByteEqualTo(base::StaticCharVector(#name))) return index; |
| |
| int Context::IntrinsicIndexForName(Handle<String> string) { |
| NATIVE_CONTEXT_INTRINSIC_FUNCTIONS(COMPARE_NAME); |
| return kNotFound; |
| } |
| |
| #undef COMPARE_NAME |
| |
| #define COMPARE_NAME(index, type, name) \ |
| { \ |
| const int name_length = static_cast<int>(arraysize(#name)) - 1; \ |
| if ((length == name_length) && strncmp(string, #name, name_length) == 0) \ |
| return index; \ |
| } |
| |
| int Context::IntrinsicIndexForName(const unsigned char* unsigned_string, |
| int length) { |
| const char* string = reinterpret_cast<const char*>(unsigned_string); |
| NATIVE_CONTEXT_INTRINSIC_FUNCTIONS(COMPARE_NAME); |
| return kNotFound; |
| } |
| |
| #undef COMPARE_NAME |
| |
| #ifdef VERIFY_HEAP |
| namespace { |
| // TODO(v8:12298): Fix js-context-specialization cctests to set up full |
| // native contexts instead of using dummy internalized strings as |
| // extensions. |
| bool IsContexExtensionTestObject(Tagged<HeapObject> extension) { |
| return IsInternalizedString(extension) && |
| String::cast(extension)->length() == 1; |
| } |
| } // namespace |
| |
| void Context::VerifyExtensionSlot(Tagged<HeapObject> extension) { |
| CHECK(scope_info()->HasContextExtensionSlot()); |
| // Early exit for potentially uninitialized contexfts. |
| if (IsUndefined(extension)) return; |
| if (IsJSContextExtensionObject(extension)) { |
| CHECK((IsBlockContext() && scope_info()->is_declaration_scope()) || |
| IsFunctionContext()); |
| } else if (IsModuleContext()) { |
| CHECK(IsSourceTextModule(extension)); |
| } else if (IsDebugEvaluateContext() || IsWithContext()) { |
| CHECK(IsJSReceiver(extension) || |
| (IsWithContext() && IsContexExtensionTestObject(extension))); |
| } else if (IsNativeContext(*this)) { |
| CHECK(IsJSGlobalObject(extension) || |
| IsContexExtensionTestObject(extension)); |
| } else if (IsScriptContext()) { |
| // Host-defined options can be stored on the context for classic scripts. |
| CHECK(IsFixedArray(extension)); |
| } |
| } |
| #endif // VERIFY_HEAP |
| |
| void Context::set_extension(Tagged<HeapObject> object, WriteBarrierMode mode) { |
| DCHECK(scope_info()->HasContextExtensionSlot()); |
| #ifdef VERIFY_HEAP |
| if (v8_flags.verify_heap) VerifyExtensionSlot(object); |
| #endif |
| set(EXTENSION_INDEX, object, mode); |
| } |
| |
| #ifdef DEBUG |
| |
| bool Context::IsBootstrappingOrValidParentContext(Tagged<Object> object, |
| Tagged<Context> child) { |
| // During bootstrapping we allow all objects to pass as |
| // contexts. This is necessary to fix circular dependencies. |
| if (child->GetIsolate()->bootstrapper()->IsActive()) return true; |
| if (!IsContext(object)) return false; |
| Tagged<Context> context = Context::cast(object); |
| return IsNativeContext(context) || context->IsScriptContext() || |
| context->IsModuleContext() || !child->IsModuleContext(); |
| } |
| |
| #endif |
| |
| void NativeContext::ResetErrorsThrown() { set_errors_thrown(Smi::FromInt(0)); } |
| |
| void NativeContext::IncrementErrorsThrown() { |
| int previous_value = errors_thrown().value(); |
| set_errors_thrown(Smi::FromInt(previous_value + 1)); |
| } |
| |
| int NativeContext::GetErrorsThrown() { return errors_thrown().value(); } |
| |
| static_assert(Context::MIN_CONTEXT_SLOTS == 2); |
| static_assert(Context::MIN_CONTEXT_EXTENDED_SLOTS == 3); |
| static_assert(NativeContext::kScopeInfoOffset == |
| Context::OffsetOfElementAt(NativeContext::SCOPE_INFO_INDEX)); |
| static_assert(NativeContext::kPreviousOffset == |
| Context::OffsetOfElementAt(NativeContext::PREVIOUS_INDEX)); |
| static_assert(NativeContext::kExtensionOffset == |
| Context::OffsetOfElementAt(NativeContext::EXTENSION_INDEX)); |
| |
| static_assert(NativeContext::kStartOfStrongFieldsOffset == |
| Context::OffsetOfElementAt(-1)); |
| static_assert(NativeContext::kStartOfWeakFieldsOffset == |
| Context::OffsetOfElementAt(NativeContext::FIRST_WEAK_SLOT)); |
| static_assert(NativeContext::kMicrotaskQueueOffset == |
| Context::SizeFor(NativeContext::NATIVE_CONTEXT_SLOTS)); |
| static_assert(NativeContext::kSize == |
| (Context::SizeFor(NativeContext::NATIVE_CONTEXT_SLOTS) + |
| kSystemPointerSize)); |
| |
| #ifdef V8_ENABLE_JAVASCRIPT_PROMISE_HOOKS |
| void NativeContext::RunPromiseHook(PromiseHookType type, |
| Handle<JSPromise> promise, |
| Handle<Object> parent) { |
| Isolate* isolate = promise->GetIsolate(); |
| DCHECK(isolate->HasContextPromiseHooks()); |
| int contextSlot; |
| |
| switch (type) { |
| case PromiseHookType::kInit: |
| contextSlot = PROMISE_HOOK_INIT_FUNCTION_INDEX; |
| break; |
| case PromiseHookType::kResolve: |
| contextSlot = PROMISE_HOOK_RESOLVE_FUNCTION_INDEX; |
| break; |
| case PromiseHookType::kBefore: |
| contextSlot = PROMISE_HOOK_BEFORE_FUNCTION_INDEX; |
| break; |
| case PromiseHookType::kAfter: |
| contextSlot = PROMISE_HOOK_AFTER_FUNCTION_INDEX; |
| break; |
| default: |
| UNREACHABLE(); |
| } |
| |
| Handle<Object> hook(isolate->native_context()->get(contextSlot), isolate); |
| if (IsUndefined(*hook)) return; |
| |
| int argc = type == PromiseHookType::kInit ? 2 : 1; |
| Handle<Object> argv[2] = { |
| Handle<Object>::cast(promise), |
| parent |
| }; |
| |
| Handle<Object> receiver = isolate->global_proxy(); |
| |
| StackLimitCheck check(isolate); |
| bool failed = false; |
| if (check.HasOverflowed()) { |
| isolate->StackOverflow(); |
| failed = true; |
| } else { |
| failed = Execution::Call(isolate, hook, receiver, argc, argv).is_null(); |
| } |
| if (failed) { |
| DCHECK(isolate->has_exception()); |
| Handle<Object> exception(isolate->exception(), isolate); |
| |
| MessageLocation* no_location = nullptr; |
| Handle<JSMessageObject> message = |
| isolate->CreateMessageOrAbort(exception, no_location); |
| MessageHandler::ReportMessage(isolate, no_location, message); |
| |
| isolate->clear_exception(); |
| } |
| } |
| #endif |
| |
| } // namespace internal |
| } // namespace v8 |
