More cleanup related to setting array.length

src/accessors.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/accessors.h"
 #include "src/api.h"
 #include "src/contexts.h"
 #include "src/deoptimizer.h"
@@ skipping 186 matching lines @@
   JSArray* holder = JSArray::cast(*Utils::OpenHandle(*info.Holder()));
   Object* result = holder->length();
   info.GetReturnValue().Set(Utils::ToLocal(Handle<Object>(result, isolate)));
 }
 
 
 void Accessors::ArrayLengthSetter(
     v8::Local<v8::Name> name,
     v8::Local<v8::Value> val,
     const v8::PropertyCallbackInfo<void>& info) {
+  // TODO(verwaest): Speed up.
   i::Isolate* isolate = reinterpret_cast<i::Isolate*>(info.GetIsolate());
   HandleScope scope(isolate);
   Handle<JSObject> object = Utils::OpenHandle(*info.This());
   Handle<Object> value = Utils::OpenHandle(*val);
 
   value = FlattenNumber(isolate, value);
 
   Handle<JSArray> array_handle = Handle<JSArray>::cast(object);
   MaybeHandle<Object> maybe;
   Handle<Object> uint32_v;
   maybe = Execution::ToUint32(isolate, value);
   if (!maybe.ToHandle(&uint32_v)) {
     isolate->OptionalRescheduleException(false);
     return;
   }
   Handle<Object> number_v;
   maybe = Execution::ToNumber(isolate, value);
   if (!maybe.ToHandle(&number_v)) {
     isolate->OptionalRescheduleException(false);
     return;
   }
 
   if (uint32_v->Number() == number_v->Number()) {
-    maybe = JSArray::SetElementsLength(array_handle, uint32_v);
+    uint32_t new_length = 0;
+    CHECK(uint32_v->ToArrayLength(&new_length));
+    maybe = JSArray::ObservableSetLength(array_handle, new_length);
     if (maybe.is_null()) isolate->OptionalRescheduleException(false);
     return;
   }
 
   Handle<Object> exception =
       isolate->factory()->NewRangeError(MessageTemplate::kInvalidArrayLength);
   isolate->ScheduleThrow(*exception);
 }
 
 
@@ skipping 1250 matching lines @@
   Handle<Object> getter = v8::FromCData(isolate, &ModuleGetExport);
   Handle<Object> setter = v8::FromCData(isolate, &ModuleSetExport);
   info->set_getter(*getter);
   if (!(attributes & ReadOnly)) info->set_setter(*setter);
   return info;
 }
 
 
 }  // namespace internal
 }  // namespace v8