Changeset 197391 in webkit for trunk/Source/JavaScriptCore/runtime

Timestamp:

Mar 1, 2016, 12:11:20 AM (9 years ago)

Author:

[email protected]

Message:

PreventExtensions should be a virtual method in the method table.
​https://bugs.webkit.org/show_bug.cgi?id=154800

Reviewed by Yusuke Suzuki.

This patch makes us more consistent with how the ES6 specification models the
PreventExtensions trap. Moving this method into ClassInfo::methodTable
is a prerequisite for implementing Proxy.PreventExtensions.

• runtime/ClassInfo.h:
• runtime/JSCell.cpp:

(JSC::JSCell::getGenericPropertyNames):
(JSC::JSCell::preventExtensions):

• runtime/JSCell.h:
• runtime/JSModuleNamespaceObject.cpp:

(JSC::JSModuleNamespaceObject::JSModuleNamespaceObject):
(JSC::JSModuleNamespaceObject::finishCreation):
(JSC::JSModuleNamespaceObject::destroy):

• runtime/JSModuleNamespaceObject.h:

(JSC::JSModuleNamespaceObject::create):
(JSC::JSModuleNamespaceObject::moduleRecord):

• runtime/JSObject.cpp:

(JSC::JSObject::freeze):
(JSC::JSObject::preventExtensions):
(JSC::JSObject::reifyAllStaticProperties):

• runtime/JSObject.h:

(JSC::JSObject::isSealed):
(JSC::JSObject::isFrozen):
(JSC::JSObject::isExtensible):

• runtime/ObjectConstructor.cpp:

(JSC::objectConstructorSeal):
(JSC::objectConstructorFreeze):
(JSC::objectConstructorPreventExtensions):
(JSC::objectConstructorIsSealed):

• runtime/ReflectObject.cpp:

(JSC::reflectObjectPreventExtensions):

• runtime/Structure.cpp:

(JSC::Structure::Structure):
(JSC::Structure::preventExtensionsTransition):

• runtime/Structure.h:

Location:

trunk/Source/JavaScriptCore/runtime

Files:

• ClassInfo.h (modified) (2 diffs)
• JSCell.cpp (modified) (1 diff)
• JSCell.h (modified) (1 diff)
• JSModuleNamespaceObject.cpp (modified) (2 diffs)
• JSModuleNamespaceObject.h (modified) (2 diffs)
• JSObject.cpp (modified) (1 diff)
• JSObject.h (modified) (1 diff)
• ObjectConstructor.cpp (modified) (3 diffs)
• ReflectObject.cpp (modified) (1 diff)
• Structure.cpp (modified) (4 diffs)
• Structure.h (modified) (2 diffs)

trunk/Source/JavaScriptCore/runtime/ClassInfo.h

@@ -103 +103 @@
     typedef PassRefPtr<ArrayBufferView> (*GetTypedArrayImpl)(JSArrayBufferView*);
     GetTypedArrayImpl getTypedArrayImpl;
+
+    typedef bool (*PreventExtensionsFunctionPtr)(JSObject*, ExecState*);
+    PreventExtensionsFunctionPtr preventExtensions;
 
     typedef void (*DumpToStreamFunctionPtr)(const JSCell*, PrintStream&);
@@ -155 +158 @@
         &ClassName::slowDownAndWasteMemory, \
         &ClassName::getTypedArrayImpl, \
+        &ClassName::preventExtensions, \
         &ClassName::dumpToStream, \
         &ClassName::estimatedSize \

trunk/Source/JavaScriptCore/runtime/JSCell.cpp

@@ -271 +271 @@
 }
 
+bool JSCell::preventExtensions(JSObject*, ExecState*)
+{
+    RELEASE_ASSERT_NOT_REACHED();
+}
+
 } // namespace JSC

trunk/Source/JavaScriptCore/runtime/JSCell.h

@@ -207 +207 @@
     static NO_RETURN_DUE_TO_CRASH void getStructurePropertyNames(JSObject*, ExecState*, PropertyNameArray&, EnumerationMode);
     static NO_RETURN_DUE_TO_CRASH void getGenericPropertyNames(JSObject*, ExecState*, PropertyNameArray&, EnumerationMode);
+    static NO_RETURN_DUE_TO_CRASH bool preventExtensions(JSObject*, ExecState*);
 
     static String className(const JSObject*);

trunk/Source/JavaScriptCore/runtime/JSModuleNamespaceObject.cpp

@@ -50 +50 @@
 }
 
-void JSModuleNamespaceObject::finishCreation(VM& vm, JSGlobalObject* globalObject, JSModuleRecord* moduleRecord, const IdentifierSet& exports)
+void JSModuleNamespaceObject::finishCreation(ExecState* exec, JSGlobalObject* globalObject, JSModuleRecord* moduleRecord, const IdentifierSet& exports)
 {
+    VM& vm = exec->vm();
     Base::finishCreation(vm);
     ASSERT(inherits(info()));
@@ -79 +80 @@
     // http://www.ecma-international.org/ecma-262/6.0/#sec-module-namespace-exotic-objects-isextensible
     // http://www.ecma-international.org/ecma-262/6.0/#sec-module-namespace-exotic-objects-preventextensions
-    preventExtensions(vm);
+    methodTable(vm)->preventExtensions(this, exec);
+    ASSERT(!exec->hadException());
 }
 

trunk/Source/JavaScriptCore/runtime/JSModuleNamespaceObject.h

@@ -42 +42 @@
     {
         JSModuleNamespaceObject* object = new (NotNull, allocateCell<JSModuleNamespaceObject>(exec->vm().heap)) JSModuleNamespaceObject(exec->vm(), structure);
-        object->finishCreation(exec->vm(), globalObject, moduleRecord, exports);
+        object->finishCreation(exec, globalObject, moduleRecord, exports);
         return object;
     }
@@ -63 +63 @@
 
 protected:
-    JS_EXPORT_PRIVATE void finishCreation(VM&, JSGlobalObject*, JSModuleRecord*, const IdentifierSet& exports);
+    JS_EXPORT_PRIVATE void finishCreation(ExecState*, JSGlobalObject*, JSModuleRecord*, const IdentifierSet& exports);
     JS_EXPORT_PRIVATE JSModuleNamespaceObject(VM&, Structure*);
 

trunk/Source/JavaScriptCore/runtime/JSObject.cpp

@@ -1676 +1676 @@
 }
 
-void JSObject::preventExtensions(VM& vm)
-{
-    if (!isExtensible())
-        return;
-    enterDictionaryIndexingMode(vm);
-    setStructure(vm, Structure::preventExtensionsTransition(vm, structure(vm)));
+bool JSObject::preventExtensions(JSObject* object, ExecState* exec)
+{
+    if (!object->isExtensible())
+        return true;
+
+    VM& vm = exec->vm();
+    object->enterDictionaryIndexingMode(vm);
+    object->setStructure(vm, Structure::preventExtensionsTransition(vm, object->structure(vm)));
+    return true;
 }
 

trunk/Source/JavaScriptCore/runtime/JSObject.h

@@ -615 +615 @@
     JS_EXPORT_PRIVATE void seal(VM&);
     JS_EXPORT_PRIVATE void freeze(VM&);
-    JS_EXPORT_PRIVATE void preventExtensions(VM&);
+    JS_EXPORT_PRIVATE static bool preventExtensions(JSObject*, ExecState*);
     bool isSealed(VM& vm) { return structure(vm)->isSealed(vm); }
     bool isFrozen(VM& vm) { return structure(vm)->isFrozen(vm); }

trunk/Source/JavaScriptCore/runtime/ObjectConstructor.cpp

@@ -517 +517 @@
 
     // 3. Set the [[Extensible]] internal property of O to false.
-    object->preventExtensions(exec->vm());
+    object->methodTable(exec->vm())->preventExtensions(object, exec);
+    if (exec->hadException())
+        return JSValue::encode(JSValue());
 
     // 4. Return O.
@@ -555 +557 @@
 
     // 3. Set the [[Extensible]] internal property of O to false.
-    object->preventExtensions(exec->vm());
+    object->methodTable(exec->vm())->preventExtensions(object, exec);
+    if (exec->hadException())
+        return nullptr;
 
     // 4. Return O.
@@ -567 +571 @@
     if (!obj.isObject())
         return JSValue::encode(obj);
-    return JSValue::encode(objectConstructorFreeze(exec, asObject(obj)));
+    JSObject* result = objectConstructorFreeze(exec, asObject(obj));
+    if (exec->hadException())
+        return JSValue::encode(JSValue());
+    return JSValue::encode(result);
 }
 
 EncodedJSValue JSC_HOST_CALL objectConstructorPreventExtensions(ExecState* exec)
 {
-    JSValue obj = exec->argument(0);
-    if (!obj.isObject())
-        return JSValue::encode(obj);
-    asObject(obj)->preventExtensions(exec->vm());
-    return JSValue::encode(obj);
+    JSValue argument = exec->argument(0);
+    if (!argument.isObject())
+        return JSValue::encode(argument);
+    JSObject* object = asObject(argument);
+    object->methodTable(exec->vm())->preventExtensions(object, exec);
+    return JSValue::encode(object);
 }
 

trunk/Source/JavaScriptCore/runtime/ReflectObject.cpp

@@ -187 +187 @@
     if (!target.isObject())
         return JSValue::encode(throwTypeError(exec, ASCIILiteral("Reflect.preventExtensions requires the first argument be an object")));
-    asObject(target)->preventExtensions(exec->vm());
-    return JSValue::encode(jsBoolean(true));
+    JSObject* object = asObject(target);
+    bool result = object->methodTable(exec->vm())->preventExtensions(object, exec);
+    if (exec->hadException())
+        return JSValue::encode(JSValue());
+    return JSValue::encode(jsBoolean(result));
 }
 

trunk/Source/JavaScriptCore/runtime/Structure.cpp

@@ -204 +204 @@
     setHasNonEnumerableProperties(false);
     setAttributesInPrevious(0);
-    setPreventExtensions(false);
+    setDidPreventExtensions(false);
     setDidTransition(false);
     setStaticFunctionsReified(false);
@@ -236 +236 @@
     setHasNonEnumerableProperties(false);
     setAttributesInPrevious(0);
-    setPreventExtensions(false);
+    setDidPreventExtensions(false);
     setDidTransition(false);
     setStaticFunctionsReified(false);
@@ -267 +267 @@
     setHasNonEnumerableProperties(previous->hasNonEnumerableProperties());
     setAttributesInPrevious(0);
-    setPreventExtensions(previous->preventExtensions());
+    setDidPreventExtensions(previous->didPreventExtensions());
     setDidTransition(true);
     setStaticFunctionsReified(previous->staticFunctionsReified());
@@ -626 +626 @@
     transition->propertyTable().set(vm, transition, structure->copyPropertyTableForPinning(vm));
     transition->m_offset = structure->m_offset;
-    transition->setPreventExtensions(true);
+    transition->setDidPreventExtensions(true);
     transition->pin();
 

trunk/Source/JavaScriptCore/runtime/Structure.h

@@ -184 +184 @@
     JS_EXPORT_PRIVATE bool isSealed(VM&);
     JS_EXPORT_PRIVATE bool isFrozen(VM&);
-    bool isExtensible() const { return !preventExtensions(); }
+    bool isExtensible() const { return !didPreventExtensions(); }
     bool putWillGrowOutOfLineStorage();
     size_t suggestedNewOutOfLineStorageCapacity(); 
@@ -580 +580 @@
     DEFINE_BITFIELD(bool, hasNonEnumerableProperties, HasNonEnumerableProperties, 1, 5);
     DEFINE_BITFIELD(unsigned, attributesInPrevious, AttributesInPrevious, 14, 6);
-    DEFINE_BITFIELD(bool, preventExtensions, PreventExtensions, 1, 20);
+    DEFINE_BITFIELD(bool, didPreventExtensions, DidPreventExtensions, 1, 20);
     DEFINE_BITFIELD(bool, didTransition, DidTransition, 1, 21);
     DEFINE_BITFIELD(bool, staticFunctionsReified, StaticFunctionsReified, 1, 22);