Verify that GC can handle trailing fillers in large pages.

runtime/vm/object_test.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 // TODO(zra): Remove when tests are ready to enable.
 #include "platform/globals.h"
 
 #include "vm/assembler.h"
 #include "vm/bigint_operations.h"
 #include "vm/class_finalizer.h"
@@ skipping 2032 matching lines @@
   addr = RawObject::ToAddr(new_array.raw());
   obj = RawObject::FromAddr(addr);
   EXPECT(obj.IsArray());
   new_array ^= obj.raw();
   EXPECT_EQ(1, new_array.Length());
   addr += used_size;
   obj = RawObject::FromAddr(addr);
   EXPECT(obj.IsTypedData());
   left_over_array ^= obj.raw();
   EXPECT_EQ((6 * kWordSize), left_over_array.Length());
+
+  // 4. Verify that GC can handle the filler object for a large array.
+  array = GrowableObjectArray::New((1 * MB) >> kWordSizeLog2);
+  EXPECT_EQ(0, array.Length());
+  for (intptr_t i = 0; i < 1; i++) {
+    value = Smi::New(i);
+    array.Add(value);
+  }
+  new_array = Array::MakeArray(array);
+  EXPECT_EQ(1, new_array.Length());
+  Isolate::Current()->heap()->CollectAllGarbage();
+  EXPECT_EQ(1, new_array.Length());
 }
 
 
 TEST_CASE(InternalTypedData) {
   uint8_t data[] = { 253, 254, 255, 0, 1, 2, 3, 4 };
   intptr_t data_length = ARRAY_SIZE(data);
 
   const TypedData& int8_array =
       TypedData::Handle(TypedData::New(kTypedDataInt8ArrayCid, data_length));
   EXPECT(!int8_array.IsNull());
@@ skipping 1990 matching lines @@
   const Instance& a0 = Instance::Handle(Instance::New(clazz));
   const Instance& a1 = Instance::Handle(Instance::New(clazz));
   EXPECT(a0.raw() != a1.raw());
   EXPECT(a0.OperatorEquals(a0));
   EXPECT(a0.OperatorEquals(a1));
   EXPECT(a0.IsIdenticalTo(a0));
   EXPECT(!a0.IsIdenticalTo(a1));
 }
 
 }  // namespace dart