Reland "Make sure that memory reducer makes progress in incremental marking""

test/cctest/test-heap.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 6645 matching lines @@
   }
 
   {
     SharedFunctionInfo::Iterator iterator(isolate);
     while (iterator.Next()) sfi_count--;
   }
 
   CHECK_EQ(0, sfi_count);
 }
 
+
+template <typename T>
+static UniqueId MakeUniqueId(const Persistent<T>& p) {
+  return UniqueId(reinterpret_cast<uintptr_t>(*v8::Utils::OpenPersistent(p)));
+}
+
+
+TEST(Regress519319) {
+  CcTest::InitializeVM();
+  v8::Isolate* isolate = CcTest::isolate();
+  v8::HandleScope scope(isolate);
+  Heap* heap = CcTest::heap();
+  LocalContext context;
+
+  v8::Persistent<Value> parent;
+  v8::Persistent<Value> child;
+
+  parent.Reset(isolate, v8::Object::New(isolate));
+  child.Reset(isolate, v8::Object::New(isolate));
+
+  SimulateFullSpace(heap->old_space());
+  heap->CollectGarbage(OLD_SPACE);
+  {
+    UniqueId id = MakeUniqueId(parent);
+    isolate->SetObjectGroupId(parent, id);
+    isolate->SetReferenceFromGroup(id, child);
+  }

[Michael Lippautz, 2015/09/03 15:01:49]

nit: Please add a comment stating that we are concurrently sweeping and depend
on the timing here.

[ulan_google, 2015/09/03 15:07:01]

Done.

+  heap->StartIncrementalMarking();
+  heap->FinalizeIncrementalMarkingIfComplete("test");
+}
+
+
 }  // namespace internal
 }  // namespace v8