Reland "Remove the weak list of views from array buffers"

src/elements.cc

 // 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.
 
 #include "src/v8.h"
 
 #include "src/arguments.h"
 #include "src/conversions.h"
 #include "src/elements.h"
 #include "src/objects.h"
@@ skipping 602 matching lines @@
 
     return ElementsAccessorSubclass::GetImpl(
         receiver, holder, key, backing_store);
   }
 
   MUST_USE_RESULT static MaybeHandle<Object> GetImpl(
       Handle<Object> receiver,
       Handle<JSObject> obj,
       uint32_t key,
       Handle<FixedArrayBase> backing_store) {
-    if (key < ElementsAccessorSubclass::GetCapacityImpl(backing_store)) {
+    if (key < ElementsAccessorSubclass::GetCapacityImpl(obj, backing_store)) {
       return BackingStore::get(Handle<BackingStore>::cast(backing_store), key);
     } else {
       return backing_store->GetIsolate()->factory()->the_hole_value();
     }
   }
 
   MUST_USE_RESULT virtual PropertyAttributes GetAttributes(
       Handle<JSObject> holder, uint32_t key,
       Handle<FixedArrayBase> backing_store) final {
     return ElementsAccessorSubclass::GetAttributesImpl(holder, key,
                                                        backing_store);
   }
 
   MUST_USE_RESULT static PropertyAttributes GetAttributesImpl(
         Handle<JSObject> obj,
         uint32_t key,
         Handle<FixedArrayBase> backing_store) {
-    if (key >= ElementsAccessorSubclass::GetCapacityImpl(backing_store)) {
+    if (key >= ElementsAccessorSubclass::GetCapacityImpl(obj, backing_store)) {
       return ABSENT;
     }
     return
         Handle<BackingStore>::cast(backing_store)->is_the_hole(key)
           ? ABSENT : NONE;
   }
 
   MUST_USE_RESULT virtual MaybeHandle<AccessorPair> GetAccessorPair(
       Handle<JSObject> holder, uint32_t key,
       Handle<FixedArrayBase> backing_store) final {
@@ skipping 92 matching lines @@
 #ifdef ENABLE_SLOW_DCHECKS
     if (FLAG_enable_slow_asserts) {
       for (int i = 0; i < len0; i++) {
         DCHECK(!to->get(i)->IsTheHole());
       }
     }
 #endif
 
     // Optimize if 'other' is empty.
     // We cannot optimize if 'this' is empty, as other may have holes.
-    uint32_t len1 = ElementsAccessorSubclass::GetCapacityImpl(from);
+    uint32_t len1 = ElementsAccessorSubclass::GetCapacityImpl(holder, from);
     if (len1 == 0) return to;
 
     Isolate* isolate = from->GetIsolate();
 
     // Compute how many elements are not in other.
     uint32_t extra = 0;
     for (uint32_t y = 0; y < len1; y++) {
       uint32_t key = ElementsAccessorSubclass::GetKeyForIndexImpl(from, y);
       if (ElementsAccessorSubclass::HasElementImpl(holder, key, from)) {
         Handle<Object> value;
@@ skipping 45 matching lines @@
           result->set(len0 + index, *value);
           index++;
         }
       }
     }
     DCHECK(extra == index);
     return result;
   }
 
  protected:
-  static uint32_t GetCapacityImpl(Handle<FixedArrayBase> backing_store) {
+  static uint32_t GetCapacityImpl(Handle<JSObject> holder,
+                                  Handle<FixedArrayBase> backing_store) {
     return backing_store->length();
   }
 
-  uint32_t GetCapacity(Handle<FixedArrayBase> backing_store) final {
-    return ElementsAccessorSubclass::GetCapacityImpl(backing_store);
+  uint32_t GetCapacity(Handle<JSObject> holder,
+                       Handle<FixedArrayBase> backing_store) final {
+    return ElementsAccessorSubclass::GetCapacityImpl(holder, backing_store);
   }
 
   static uint32_t GetKeyForIndexImpl(Handle<FixedArrayBase> backing_store,
                                      uint32_t index) {
     return index;
   }
 
   virtual uint32_t GetKeyForIndex(Handle<FixedArrayBase> backing_store,
                                   uint32_t index) final {
     return ElementsAccessorSubclass::GetKeyForIndexImpl(backing_store, index);
@@ skipping 417 matching lines @@
   typedef TypedElementsAccessor<Kind> AccessorClass;
 
   friend class ElementsAccessorBase<AccessorClass,
                                     ElementsKindTraits<Kind> >;
 
   MUST_USE_RESULT static MaybeHandle<Object> GetImpl(
       Handle<Object> receiver,
       Handle<JSObject> obj,
       uint32_t key,
       Handle<FixedArrayBase> backing_store) {
-    if (key < AccessorClass::GetCapacityImpl(backing_store)) {
+    if (key < AccessorClass::GetCapacityImpl(obj, backing_store)) {
       return BackingStore::get(Handle<BackingStore>::cast(backing_store), key);
     } else {
       return backing_store->GetIsolate()->factory()->undefined_value();
     }
   }
 
   MUST_USE_RESULT static PropertyAttributes GetAttributesImpl(
       Handle<JSObject> obj,
       uint32_t key,
       Handle<FixedArrayBase> backing_store) {
-    return
-        key < AccessorClass::GetCapacityImpl(backing_store)
-          ? NONE : ABSENT;
+    return key < AccessorClass::GetCapacityImpl(obj, backing_store) ? NONE
+                                                                    : ABSENT;
   }
 
   MUST_USE_RESULT static MaybeHandle<Object> SetLengthImpl(
       Handle<JSObject> obj,
       Handle<Object> length,
       Handle<FixedArrayBase> backing_store) {
     // External arrays do not support changing their length.
     UNREACHABLE();
     return obj;
   }
 
   MUST_USE_RESULT virtual MaybeHandle<Object> Delete(
       Handle<JSObject> obj, uint32_t key, LanguageMode language_mode) final {
     // External arrays always ignore deletes.
     return obj->GetIsolate()->factory()->true_value();
   }
 
   static bool HasElementImpl(Handle<JSObject> holder, uint32_t key,
                              Handle<FixedArrayBase> backing_store) {
-    uint32_t capacity =
-        AccessorClass::GetCapacityImpl(backing_store);
+    uint32_t capacity = AccessorClass::GetCapacityImpl(holder, backing_store);
     return key < capacity;
   }
+
+  static uint32_t GetCapacityImpl(Handle<JSObject> holder,
+                                  Handle<FixedArrayBase> backing_store) {
+    Handle<JSArrayBufferView> view = Handle<JSArrayBufferView>::cast(holder);
+    if (view->WasNeutered()) return 0;
+    return backing_store->length();
+  }
 };
 
 
 
 #define EXTERNAL_ELEMENTS_ACCESSOR(Type, type, TYPE, ctype, size)    \
   typedef TypedElementsAccessor<EXTERNAL_##TYPE##_ELEMENTS>          \
       External##Type##ElementsAccessor;
 
 TYPED_ARRAYS(EXTERNAL_ELEMENTS_ACCESSOR)
 #undef EXTERNAL_ELEMENTS_ACCESSOR
@@ skipping 315 matching lines @@
     return isolate->factory()->true_value();
   }
 
   static void CopyElementsImpl(FixedArrayBase* from, uint32_t from_start,
                                FixedArrayBase* to, ElementsKind from_kind,
                                uint32_t to_start, int packed_size,
                                int copy_size) {
     UNREACHABLE();
   }
 
-  static uint32_t GetCapacityImpl(Handle<FixedArrayBase> backing_store) {
+  static uint32_t GetCapacityImpl(Handle<JSObject> holder,
+                                  Handle<FixedArrayBase> backing_store) {
     Handle<FixedArray> parameter_map = Handle<FixedArray>::cast(backing_store);
     Handle<FixedArrayBase> arguments(
         FixedArrayBase::cast(parameter_map->get(1)));
     return Max(static_cast<uint32_t>(parameter_map->length() - 2),
-               ForArray(arguments)->GetCapacity(arguments));
+               ForArray(arguments)->GetCapacity(holder, arguments));
   }
 
   static uint32_t GetKeyForIndexImpl(Handle<FixedArrayBase> dict,
                                      uint32_t index) {
     return index;
   }
 
  private:
   static Handle<Object> GetParameterMapArg(Handle<JSObject> holder,
                                            Handle<FixedArray> parameter_map,
@@ skipping 192 matching lines @@
       UNREACHABLE();
       break;
   }
 
   array->set_elements(*elms);
   array->set_length(Smi::FromInt(number_of_elements));
   return array;
 }
 
 } }  // namespace v8::internal