Speed up debug mode GC.

src/mark-compact.cc

Index: src/mark-compact.cc
===================================================================
--- src/mark-compact.cc	(revision 9765)
+++ src/mark-compact.cc	(working copy)
@@ -65,16 +65,6 @@
       collect_maps_(FLAG_collect_maps),
       tracer_(NULL),
       migration_slots_buffer_(NULL),
-#ifdef DEBUG
-      live_young_objects_size_(0),
-      live_old_pointer_objects_size_(0),
-      live_old_data_objects_size_(0),
-      live_code_objects_size_(0),
-      live_map_objects_size_(0),
-      live_cell_objects_size_(0),
-      live_lo_objects_size_(0),
-      live_bytes_(0),
-#endif
       heap_(NULL),
       code_flusher_(NULL),
       encountered_weak_maps_(NULL) { }
@@ -523,21 +513,10 @@
   }
 
 #ifdef DEBUG
-  if (!was_marked_incrementally_) {
+  if (!was_marked_incrementally_ && FLAG_verify_heap) {
     VerifyMarkbitsAreClean();
   }
 #endif
-
-#ifdef DEBUG
-  live_bytes_ = 0;
-  live_young_objects_size_ = 0;
-  live_old_pointer_objects_size_ = 0;
-  live_old_data_objects_size_ = 0;
-  live_code_objects_size_ = 0;
-  live_map_objects_size_ = 0;
-  live_cell_objects_size_ = 0;
-  live_lo_objects_size_ = 0;
-#endif
 }
 
 
@@ -2176,32 +2155,6 @@
 }
 
 
-#ifdef DEBUG
-void MarkCompactCollector::UpdateLiveObjectCount(HeapObject* obj) {
-  live_bytes_ += obj->Size();
-  if (heap()->new_space()->Contains(obj)) {
-    live_young_objects_size_ += obj->Size();
-  } else if (heap()->map_space()->Contains(obj)) {
-    ASSERT(obj->IsMap());
-    live_map_objects_size_ += obj->Size();
-  } else if (heap()->cell_space()->Contains(obj)) {
-    ASSERT(obj->IsJSGlobalPropertyCell());
-    live_cell_objects_size_ += obj->Size();
-  } else if (heap()->old_pointer_space()->Contains(obj)) {
-    live_old_pointer_objects_size_ += obj->Size();
-  } else if (heap()->old_data_space()->Contains(obj)) {
-    live_old_data_objects_size_ += obj->Size();
-  } else if (heap()->code_space()->Contains(obj)) {
-    live_code_objects_size_ += obj->Size();
-  } else if (heap()->lo_space()->Contains(obj)) {
-    live_lo_objects_size_ += obj->Size();
-  } else {
-    UNREACHABLE();
-  }
-}
-#endif  // DEBUG
-
-
 void MarkCompactCollector::ReattachInitialMaps() {
   HeapObjectIterator map_iterator(heap()->map_space());
   for (HeapObject* obj = map_iterator.Next();
@@ -3649,8 +3602,6 @@
   // of the previous ones.
   SweepSpace(heap()->map_space(), PRECISE);
 
-  ASSERT(live_map_objects_size_ <= heap()->map_space()->Size());
-
   // Deallocate unmarked objects and clear marked bits for marked objects.
   heap_->lo_space()->FreeUnmarkedObjects();
 }