- Pass the knowledge whether the old GC is compacting to the GC prologue and ...

src/mark-compact.cc

 // Copyright 2006-2008 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 40 matching lines @@
 // collection.
 int MarkCompactCollector::live_bytes_ = 0;
 int MarkCompactCollector::live_young_objects_ = 0;
 int MarkCompactCollector::live_old_data_objects_ = 0;
 int MarkCompactCollector::live_old_pointer_objects_ = 0;
 int MarkCompactCollector::live_code_objects_ = 0;
 int MarkCompactCollector::live_map_objects_ = 0;
 int MarkCompactCollector::live_lo_objects_ = 0;
 #endif
 
-void MarkCompactCollector::CollectGarbage(GCTracer* tracer) {
-  // Rather than passing the tracer around we stash it in a static member
-  // variable.
-  tracer_ = tracer;
-  Prepare();
+void MarkCompactCollector::CollectGarbage() {
+  // Make sure that Prepare() has been called. The individual steps below will
+  // update the state as they proceed.
+  ASSERT(state_ == PREPARE_GC);
+
   // Prepare has selected whether to compact the old generation or not.
   // Tell the tracer.
   if (IsCompacting()) tracer_->set_is_compacting();
 
   MarkLiveObjects();
 
   if (FLAG_collect_maps) ClearNonLiveTransitions();
 
   SweepLargeObjectSpace();
 
@@ skipping 13 matching lines @@
   Finish();
 
   // Save the count of marked objects remaining after the collection and
   // null out the GC tracer.
   previous_marked_count_ = tracer_->marked_count();
   ASSERT(previous_marked_count_ == 0);
   tracer_ = NULL;
 }
 
 
-void MarkCompactCollector::Prepare() {
+void MarkCompactCollector::Prepare(GCTracer* tracer) {
+  // Rather than passing the tracer around we stash it in a static member
+  // variable.
+  tracer_ = tracer;
+
   static const int kFragmentationLimit = 50;  // Percent.
 #ifdef DEBUG
   ASSERT(state_ == IDLE);
   state_ = PREPARE_GC;
 #endif
   ASSERT(!FLAG_always_compact || !FLAG_never_compact);
 
   compacting_collection_ = FLAG_always_compact;
 
   // We compact the old generation if it gets too fragmented (ie, we could
@@ skipping 124 matching lines @@
   if (!Heap::InNewSpace(object) && Heap::InNewSpace(first)) return object;
 
   *p = first;
   return HeapObject::cast(first);
 }
 
 
 // Helper class for marking pointers in HeapObjects.
 class MarkingVisitor : public ObjectVisitor {
  public:
-
   void VisitPointer(Object** p) {
     MarkObjectByPointer(p);
   }
 
   void VisitPointers(Object** start, Object** end) {
     // Mark all objects pointed to in [start, end).
     const int kMinRangeForMarkingRecursion = 64;
     if (end - start >= kMinRangeForMarkingRecursion) {
       if (VisitUnmarkedObjects(start, end)) return;
       // We are close to a stack overflow, so just mark the objects.
@@ skipping 1500 matching lines @@
 
 void MarkCompactCollector::RebuildRSets() {
 #ifdef DEBUG
   ASSERT(state_ == RELOCATE_OBJECTS);
   state_ = REBUILD_RSETS;
 #endif
   Heap::RebuildRSets();
 }
 
 } }  // namespace v8::internal