Revert r12825 and r12796 from trunk.

src/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 402 matching lines @@
 #endif  // DEBUG
 }
 
 
 void Heap::GarbageCollectionPrologue() {
   isolate_->transcendental_cache()->Clear();
   ClearJSFunctionResultCaches();
   gc_count_++;
   unflattened_strings_length_ = 0;
 
-  bool should_enable_code_flushing = FLAG_flush_code;
-#ifdef ENABLE_DEBUGGER_SUPPORT
-  if (isolate_->debug()->IsLoaded() || isolate_->debug()->has_break_points()) {
-    should_enable_code_flushing = false;
-  }
-#endif
-  mark_compact_collector()->EnableCodeFlushing(should_enable_code_flushing);
-
 #ifdef VERIFY_HEAP
   if (FLAG_verify_heap) {
     Verify();
   }
 #endif
 
 #ifdef DEBUG
   ASSERT(allocation_allowed_ && gc_state_ == NOT_IN_GC);
   allow_allocation(false);
 
@@ skipping 879 matching lines @@
   for (HeapObject* heap_object = cell_iterator.Next();
        heap_object != NULL;
        heap_object = cell_iterator.Next()) {
     if (heap_object->IsJSGlobalPropertyCell()) {
       JSGlobalPropertyCell* cell = JSGlobalPropertyCell::cast(heap_object);
       Address value_address = cell->ValueAddress();
       scavenge_visitor.VisitPointer(reinterpret_cast<Object**>(value_address));
     }
   }
 
-  // Copy objects reachable from the code flushing candidates list.
-  MarkCompactCollector* collector = mark_compact_collector();
-  if (collector->is_code_flushing_enabled()) {
-    collector->code_flusher()->IteratePointersToFromSpace(&scavenge_visitor);
-  }
-
   // Scavenge object reachable from the native contexts list directly.
   scavenge_visitor.VisitPointer(BitCast<Object**>(&native_contexts_list_));
 
   new_space_front = DoScavenge(&scavenge_visitor, new_space_front);
   isolate_->global_handles()->IdentifyNewSpaceWeakIndependentHandles(
       &IsUnscavengedHeapObject);
   isolate_->global_handles()->IterateNewSpaceWeakIndependentRoots(
       &scavenge_visitor);
   new_space_front = DoScavenge(&scavenge_visitor, new_space_front);
 
@@ skipping 4195 matching lines @@
 
 
 bool Heap::LookupSymbolIfExists(String* string, String** symbol) {
   if (string->IsSymbol()) {
     *symbol = string;
     return true;
   }
   return symbol_table()->LookupSymbolIfExists(string, symbol);
 }
 
-
 void Heap::ZapFromSpace() {
   NewSpacePageIterator it(new_space_.FromSpaceStart(),
                           new_space_.FromSpaceEnd());
   while (it.has_next()) {
     NewSpacePage* page = it.next();
     for (Address cursor = page->area_start(), limit = page->area_end();
          cursor < limit;
          cursor += kPointerSize) {
       Memory::Address_at(cursor) = kFromSpaceZapValue;
     }
@@ skipping 1805 matching lines @@
       static_cast<int>(object_sizes_last_time_[index]));
   FIXED_ARRAY_SUB_INSTANCE_TYPE_LIST(ADJUST_LAST_TIME_OBJECT_COUNT)
 #undef ADJUST_LAST_TIME_OBJECT_COUNT
 
   memcpy(object_counts_last_time_, object_counts_, sizeof(object_counts_));
   memcpy(object_sizes_last_time_, object_sizes_, sizeof(object_sizes_));
   ClearObjectStats();
 }
 
 } }  // namespace v8::internal