Reland of "[heap] Parallel newspace evacuation, semispace copy, and compaction \o/"

src/heap/array-buffer-tracker.cc

 // Copyright 2015 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/heap/array-buffer-tracker.h"
 #include "src/heap/heap.h"
 #include "src/isolate.h"
 #include "src/objects.h"
 #include "src/objects-inl.h"
 #include "src/v8.h"
@@ skipping 59 matching lines @@
   size_t length = (*live_buffers)[data];
   live_buffers->erase(data);
   not_yet_discovered_buffers->erase(data);
 
   heap()->update_amount_of_external_allocated_memory(
       -static_cast<int64_t>(length));
 }
 
 
 void ArrayBufferTracker::MarkLive(JSArrayBuffer* buffer) {
+  base::LockGuard<base::Mutex> guard(&mutex_);
   void* data = buffer->backing_store();
 
   // ArrayBuffer might be in the middle of being constructed.
   if (data == heap()->undefined_value()) return;
   if (heap()->InNewSpace(buffer)) {
     not_yet_discovered_array_buffers_for_scavenge_.erase(data);
   } else {
     not_yet_discovered_array_buffers_.erase(data);
   }
 }
@@ skipping 26 matching lines @@
 }
 
 
 void ArrayBufferTracker::PrepareDiscoveryInNewSpace() {
   not_yet_discovered_array_buffers_for_scavenge_ =
       live_array_buffers_for_scavenge_;
 }
 
 
 void ArrayBufferTracker::Promote(JSArrayBuffer* buffer) {
+  base::LockGuard<base::Mutex> guard(&mutex_);
+
   if (buffer->is_external()) return;
   void* data = buffer->backing_store();
   if (!data) return;
   // ArrayBuffer might be in the middle of being constructed.
   if (data == heap()->undefined_value()) return;
   DCHECK(live_array_buffers_for_scavenge_.count(data) > 0);
   live_array_buffers_[data] = live_array_buffers_for_scavenge_[data];
   live_array_buffers_for_scavenge_.erase(data);
   not_yet_discovered_array_buffers_for_scavenge_.erase(data);
 }
 
 }  // namespace internal
 }  // namespace v8