Avoid reading RawObject::class_ directly in the runtime.

runtime/vm/gc_marker.cc

 // Copyright (c) 2011, 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.
 
 #include "vm/gc_marker.h"
 
 #include "vm/allocation.h"
 #include "vm/dart_api_state.h"
 #include "vm/isolate.h"
 #include "vm/pages.h"
@@ skipping 98 matching lines @@
   MarkingStackChunk* empty_chunks_;
   RawObject** marking_stack_;
   uint32_t top_;
 
   DISALLOW_COPY_AND_ASSIGN(MarkingStack);
 };
 
 
 class MarkingVisitor : public ObjectPointerVisitor {
  public:
-  MarkingVisitor(Heap* heap, PageSpace* page_space, MarkingStack* marking_stack)
-      : heap_(heap),
+  MarkingVisitor(Isolate* isolate,
+                 Heap* heap,
+                 PageSpace* page_space,
+                 MarkingStack* marking_stack)
+      : isolate_(isolate),
+        heap_(heap),
         vm_heap_(Dart::vm_isolate()->heap()),
         page_space_(page_space),
         marking_stack_(marking_stack) {
     ASSERT(heap_ != vm_heap_);
   }
 
   MarkingStack* marking_stack() const { return marking_stack_; }
 
   void VisitPointers(RawObject** first, RawObject** last) {
     for (RawObject** current = first; current <= last; current++) {
       MarkObject(*current);
     }
   }
 
  private:
   void MarkAndPush(RawObject* raw_obj) {
     ASSERT(raw_obj->IsHeapObject());
     ASSERT(page_space_->Contains(RawObject::ToAddr(raw_obj)));
 
     // Mark the object and push it on the marking stack.
     ASSERT(!raw_obj->IsMarked());
-    RawClass* raw_class = raw_obj->ptr()->class_;
+    RawClass* raw_class = isolate_->class_table()->At(raw_obj->GetClassIndex());
     raw_obj->SetMarkBit();
     marking_stack_->Push(raw_obj);
 
     // Update the number of used bytes on this page for fast accounting.
     HeapPage* page = PageSpace::PageFor(raw_obj);
     page->AddUsed(raw_obj->Size());
 
     // TODO(iposva): Should we mark the classes early?
     MarkObject(raw_class);
   }
@@ skipping 14 matching lines @@
     uword raw_addr = RawObject::ToAddr(raw_obj);
     // TODO(iposva): Premark vm_isolate objects, to avoid this extra check here.
     if (vm_heap_->Contains(raw_addr)) {
       return;
     }
     // TODO(iposva): merge old and code spaces.
     ASSERT(page_space_->Contains(raw_addr));
     MarkAndPush(raw_obj);
   }
 
+  Isolate* isolate_;
   Heap* heap_;
   Heap* vm_heap_;
   PageSpace* page_space_;
   MarkingStack* marking_stack_;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(MarkingVisitor);
 };
 
 
 bool IsUnreachable(const RawObject* raw_obj) {
@@ skipping 120 matching lines @@
     raw_obj->VisitPointers(visitor);
   }
 }
 
 
 void GCMarker::MarkObjects(Isolate* isolate,
                            PageSpace* page_space,
                            bool invoke_api_callbacks) {
   MarkingStack marking_stack;
   Prologue(isolate, invoke_api_callbacks);
-  MarkingVisitor mark(heap_, page_space, &marking_stack);
+  MarkingVisitor mark(isolate, heap_, page_space, &marking_stack);
   IterateRoots(isolate, &mark, !invoke_api_callbacks);
   DrainMarkingStack(isolate, &mark);
   IterateWeakReferences(isolate, &mark);
   MarkingWeakVisitor mark_weak;
   IterateWeakRoots(isolate, &mark_weak, invoke_api_callbacks);
   Epilogue(isolate, invoke_api_callbacks);
 }
 
 }  // namespace dart