From e30b202d683e36731d9674ebf75803990a33816e Mon Sep 17 00:00:00 2001 From: Aaron Kennedy Date: Thu, 27 Oct 2011 11:31:56 +0100 Subject: [PATCH 02/13] Add a "fallback" mode for named property interceptors By default interceptors are called before the normal property resolution on objects. When an interceptor is installed as a "fallback" interceptor, it is only called if the object doesn't already have the property. In the case of a global object having an fallback interceptor, the interceptor is not invoked at all for var or function declarations. --- include/v8.h | 7 +++++++ src/api.cc | 29 +++++++++++++++++++++++++++++ src/factory.cc | 3 +++ src/handles.cc | 6 ++++-- src/handles.h | 3 ++- src/objects-inl.h | 15 +++++++++++++++ src/objects.cc | 24 +++++++++++++++++------- src/objects.h | 16 ++++++++++++---- src/runtime.cc | 11 ++++++----- 9 files changed, 95 insertions(+), 19 deletions(-) diff --git a/include/v8.h b/include/v8.h index 86ea70f..d2e6c32 100644 --- a/include/v8.h +++ b/include/v8.h @@ -2305,6 +2305,7 @@ class V8EXPORT FunctionTemplate : public Template { NamedPropertyQuery query, NamedPropertyDeleter remover, NamedPropertyEnumerator enumerator, + bool is_fallback, Handle data); void SetIndexedInstancePropertyHandler(IndexedPropertyGetter getter, IndexedPropertySetter setter, @@ -2388,6 +2389,12 @@ class V8EXPORT ObjectTemplate : public Template { NamedPropertyDeleter deleter = 0, NamedPropertyEnumerator enumerator = 0, Handle data = Handle()); + void SetFallbackPropertyHandler(NamedPropertyGetter getter, + NamedPropertySetter setter = 0, + NamedPropertyQuery query = 0, + NamedPropertyDeleter deleter = 0, + NamedPropertyEnumerator enumerator = 0, + Handle data = Handle()); /** * Sets an indexed property handler on the object template. diff --git a/src/api.cc b/src/api.cc index 996812e..e0f3b5a 100644 --- a/src/api.cc +++ b/src/api.cc @@ -1123,6 +1123,7 @@ void FunctionTemplate::SetNamedInstancePropertyHandler( NamedPropertyQuery query, NamedPropertyDeleter remover, NamedPropertyEnumerator enumerator, + bool is_fallback, Handle data) { i::Isolate* isolate = Utils::OpenHandle(this)->GetIsolate(); if (IsDeadCheck(isolate, @@ -1141,6 +1142,7 @@ void FunctionTemplate::SetNamedInstancePropertyHandler( if (query != 0) SET_FIELD_WRAPPED(obj, set_query, query); if (remover != 0) SET_FIELD_WRAPPED(obj, set_deleter, remover); if (enumerator != 0) SET_FIELD_WRAPPED(obj, set_enumerator, enumerator); + obj->set_is_fallback(i::Smi::FromInt(is_fallback)); if (data.IsEmpty()) data = v8::Undefined(); obj->set_data(*Utils::OpenHandle(*data)); @@ -1285,6 +1287,33 @@ void ObjectTemplate::SetNamedPropertyHandler(NamedPropertyGetter getter, query, remover, enumerator, + false, + data); +} + + +void ObjectTemplate::SetFallbackPropertyHandler(NamedPropertyGetter getter, + NamedPropertySetter setter, + NamedPropertyQuery query, + NamedPropertyDeleter remover, + NamedPropertyEnumerator enumerator, + Handle data) { + i::Isolate* isolate = Utils::OpenHandle(this)->GetIsolate(); + if (IsDeadCheck(isolate, "v8::ObjectTemplate::SetNamedPropertyHandler()")) { + return; + } + ENTER_V8(isolate); + i::HandleScope scope(isolate); + EnsureConstructor(this); + i::FunctionTemplateInfo* constructor = + i::FunctionTemplateInfo::cast(Utils::OpenHandle(this)->constructor()); + i::Handle cons(constructor); + Utils::ToLocal(cons)->SetNamedInstancePropertyHandler(getter, + setter, + query, + remover, + enumerator, + true, data); } diff --git a/src/factory.cc b/src/factory.cc index 15f640e..1b95ed1 100644 --- a/src/factory.cc +++ b/src/factory.cc @@ -1213,6 +1213,9 @@ Handle Factory::CreateApiFunction( // Set interceptor information in the map. if (!obj->named_property_handler()->IsUndefined()) { map->set_has_named_interceptor(); + InterceptorInfo *nph = InterceptorInfo::cast(obj->named_property_handler()); + bool is_fallback = nph->is_fallback()->IsUndefined()?false:nph->is_fallback()->value(); + map->set_named_interceptor_is_fallback(is_fallback); } if (!obj->indexed_property_handler()->IsUndefined()) { map->set_has_indexed_interceptor(); diff --git a/src/handles.cc b/src/handles.cc index 62851f3..790d224 100644 --- a/src/handles.cc +++ b/src/handles.cc @@ -269,9 +269,11 @@ Handle SetProperty(Handle object, Handle key, Handle value, PropertyAttributes attributes, - StrictModeFlag strict_mode) { + StrictModeFlag strict_mode, + bool skip_fallback_interceptor) { CALL_HEAP_FUNCTION(object->GetIsolate(), - object->SetProperty(*key, *value, attributes, strict_mode), + object->SetProperty(*key, *value, attributes, strict_mode, + skip_fallback_interceptor), Object); } diff --git a/src/handles.h b/src/handles.h index 06e47fc..c359cb3 100644 --- a/src/handles.h +++ b/src/handles.h @@ -190,7 +190,8 @@ Handle SetProperty(Handle object, Handle key, Handle value, PropertyAttributes attributes, - StrictModeFlag strict_mode); + StrictModeFlag strict_mode, + bool skip_fallback_interceptor = false); Handle SetProperty(Handle object, Handle key, diff --git a/src/objects-inl.h b/src/objects-inl.h index 34cae9f..1cfea84 100644 --- a/src/objects-inl.h +++ b/src/objects-inl.h @@ -2754,6 +2754,20 @@ void Map::set_is_shared(bool value) { bool Map::is_shared() { return ((1 << kIsShared) & bit_field3()) != 0; } + +void Map::set_named_interceptor_is_fallback(bool value) +{ + if (value) { + set_bit_field3(bit_field3() | (1 << kNamedInterceptorIsFallback)); + } else { + set_bit_field3(bit_field3() & ~(1 << kNamedInterceptorIsFallback)); + } +} + +bool Map::named_interceptor_is_fallback() +{ + return ((1 << kNamedInterceptorIsFallback) & bit_field3()) != 0; +} JSFunction* Map::unchecked_constructor() { @@ -3255,6 +3269,7 @@ ACCESSORS(InterceptorInfo, query, Object, kQueryOffset) ACCESSORS(InterceptorInfo, deleter, Object, kDeleterOffset) ACCESSORS(InterceptorInfo, enumerator, Object, kEnumeratorOffset) ACCESSORS(InterceptorInfo, data, Object, kDataOffset) +ACCESSORS(InterceptorInfo, is_fallback, Smi, kFallbackOffset) ACCESSORS(CallHandlerInfo, callback, Object, kCallbackOffset) ACCESSORS(CallHandlerInfo, data, Object, kDataOffset) diff --git a/src/objects.cc b/src/objects.cc index 2946d02..f5b6bee 100644 --- a/src/objects.cc +++ b/src/objects.cc @@ -1980,9 +1980,10 @@ MaybeObject* JSObject::SetPropertyWithInterceptor( MaybeObject* JSReceiver::SetProperty(String* name, Object* value, PropertyAttributes attributes, - StrictModeFlag strict_mode) { + StrictModeFlag strict_mode, + bool skip_fallback_interceptor) { LookupResult result(GetIsolate()); - LocalLookup(name, &result); + LocalLookup(name, &result, skip_fallback_interceptor); return SetProperty(&result, name, value, attributes, strict_mode); } @@ -4213,7 +4214,8 @@ AccessorDescriptor* Map::FindAccessor(String* name) { } -void JSReceiver::LocalLookup(String* name, LookupResult* result) { +void JSReceiver::LocalLookup(String* name, LookupResult* result, + bool skip_fallback_interceptor) { ASSERT(name->IsString()); Heap* heap = GetHeap(); @@ -4245,23 +4247,31 @@ void JSReceiver::LocalLookup(String* name, LookupResult* result) { } // Check for lookup interceptor except when bootstrapping. - if (js_object->HasNamedInterceptor() && - !heap->isolate()->bootstrapper()->IsActive()) { + bool wouldIntercept = js_object->HasNamedInterceptor() && + !heap->isolate()->bootstrapper()->IsActive(); + if (wouldIntercept && !map()->named_interceptor_is_fallback()) { result->InterceptorResult(js_object); return; } js_object->LocalLookupRealNamedProperty(name, result); + + if (wouldIntercept && !skip_fallback_interceptor && !result->IsProperty() && + map()->named_interceptor_is_fallback()) { + result->InterceptorResult(js_object); + return; + } } -void JSReceiver::Lookup(String* name, LookupResult* result) { +void JSReceiver::Lookup(String* name, LookupResult* result, + bool skip_fallback_interceptor) { // Ecma-262 3rd 8.6.2.4 Heap* heap = GetHeap(); for (Object* current = this; current != heap->null_value(); current = JSObject::cast(current)->GetPrototype()) { - JSReceiver::cast(current)->LocalLookup(name, result); + JSReceiver::cast(current)->LocalLookup(name, result, skip_fallback_interceptor); if (result->IsProperty()) return; } result->NotFound(); diff --git a/src/objects.h b/src/objects.h index d96e5f9..ed40061 100644 --- a/src/objects.h +++ b/src/objects.h @@ -1362,7 +1362,8 @@ class JSReceiver: public HeapObject { MUST_USE_RESULT MaybeObject* SetProperty(String* key, Object* value, PropertyAttributes attributes, - StrictModeFlag strict_mode); + StrictModeFlag strict_mode, + bool skip_fallback_interceptor = false); MUST_USE_RESULT MaybeObject* SetProperty(LookupResult* result, String* key, Object* value, @@ -1414,8 +1415,8 @@ class JSReceiver: public HeapObject { // Lookup a property. If found, the result is valid and has // detailed information. - void LocalLookup(String* name, LookupResult* result); - void Lookup(String* name, LookupResult* result); + void LocalLookup(String* name, LookupResult* result, bool skip_fallback_interceptor = false); + void Lookup(String* name, LookupResult* result, bool skip_fallback_interceptor = false); protected: Smi* GenerateIdentityHash(); @@ -4242,6 +4243,10 @@ class Map: public HeapObject { inline void set_is_access_check_needed(bool access_check_needed); inline bool is_access_check_needed(); + // Whether the named interceptor is a fallback interceptor or not + inline void set_named_interceptor_is_fallback(bool value); + inline bool named_interceptor_is_fallback(); + // [prototype]: implicit prototype object. DECL_ACCESSORS(prototype, Object) @@ -4506,6 +4511,7 @@ class Map: public HeapObject { // Bit positions for bit field 3 static const int kIsShared = 0; + static const int kNamedInterceptorIsFallback = 1; // Layout of the default cache. It holds alternating name and code objects. static const int kCodeCacheEntrySize = 2; @@ -7390,6 +7396,7 @@ class InterceptorInfo: public Struct { DECL_ACCESSORS(deleter, Object) DECL_ACCESSORS(enumerator, Object) DECL_ACCESSORS(data, Object) + DECL_ACCESSORS(is_fallback, Smi) static inline InterceptorInfo* cast(Object* obj); @@ -7409,7 +7416,8 @@ class InterceptorInfo: public Struct { static const int kDeleterOffset = kQueryOffset + kPointerSize; static const int kEnumeratorOffset = kDeleterOffset + kPointerSize; static const int kDataOffset = kEnumeratorOffset + kPointerSize; - static const int kSize = kDataOffset + kPointerSize; + static const int kFallbackOffset = kDataOffset + kPointerSize; + static const int kSize = kFallbackOffset + kPointerSize; private: DISALLOW_IMPLICIT_CONSTRUCTORS(InterceptorInfo); diff --git a/src/runtime.cc b/src/runtime.cc index 9c23c2c..0e256c1 100644 --- a/src/runtime.cc +++ b/src/runtime.cc @@ -1330,7 +1330,7 @@ RUNTIME_FUNCTION(MaybeObject*, Runtime_DeclareGlobals) { // Lookup the property in the global object, and don't set the // value of the variable if the property is already there. LookupResult lookup(isolate); - global->Lookup(*name, &lookup); + global->Lookup(*name, &lookup, true); if (lookup.IsProperty()) { // We found an existing property. Unless it was an interceptor // that claims the property is absent, skip this declaration. @@ -1357,7 +1357,7 @@ RUNTIME_FUNCTION(MaybeObject*, Runtime_DeclareGlobals) { } LookupResult lookup(isolate); - global->LocalLookup(*name, &lookup); + global->LocalLookup(*name, &lookup, true); // Compute the property attributes. According to ECMA-262, section // 13, page 71, the property must be read-only and @@ -1398,7 +1398,8 @@ RUNTIME_FUNCTION(MaybeObject*, Runtime_DeclareGlobals) { name, value, static_cast(attr), - strict_mode)); + strict_mode, + true)); } } @@ -1534,7 +1535,7 @@ RUNTIME_FUNCTION(MaybeObject*, Runtime_InitializeVarGlobal) { while (object->IsJSObject() && JSObject::cast(object)->map()->is_hidden_prototype()) { JSObject* raw_holder = JSObject::cast(object); - raw_holder->LocalLookup(*name, &lookup); + raw_holder->LocalLookup(*name, &lookup, true); if (lookup.IsProperty() && lookup.type() == INTERCEPTOR) { HandleScope handle_scope(isolate); Handle holder(raw_holder); @@ -1557,7 +1558,7 @@ RUNTIME_FUNCTION(MaybeObject*, Runtime_InitializeVarGlobal) { // Reload global in case the loop above performed a GC. global = isolate->context()->global(); if (assign) { - return global->SetProperty(*name, args[2], attributes, strict_mode); + return global->SetProperty(*name, args[2], attributes, strict_mode, true); } return isolate->heap()->undefined_value(); } -- 1.7.4.1