[heap] Untangle Marking and friends from heap dependencies.

src/heap/incremental-marking.cc

 // Copyright 2012 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/incremental-marking.h"
 
 #include "src/code-stubs.h"
 #include "src/compilation-cache.h"
 #include "src/conversions.h"
 #include "src/heap/gc-idle-time-handler.h"
@@ skipping 31 matching lines @@
       idle_marking_delay_counter_(0),
       unscanned_bytes_of_large_object_(0),
       was_activated_(false),
       black_allocation_(false),
       finalize_marking_completed_(false),
       incremental_marking_finalization_rounds_(0),
       request_type_(NONE) {}
 
 bool IncrementalMarking::BaseRecordWrite(HeapObject* obj, Object* value) {
   HeapObject* value_heap_obj = HeapObject::cast(value);
-  MarkBit value_bit = Marking::MarkBitFrom(value_heap_obj);
+  MarkBit value_bit = ObjectMarking::MarkBitFrom(value_heap_obj);
   DCHECK(!Marking::IsImpossible(value_bit));
 
-  MarkBit obj_bit = Marking::MarkBitFrom(obj);
+  MarkBit obj_bit = ObjectMarking::MarkBitFrom(obj);
   DCHECK(!Marking::IsImpossible(obj_bit));
   bool is_black = Marking::IsBlack(obj_bit);
 
   if (is_black && Marking::IsWhite(value_bit)) {
     WhiteToGreyAndPush(value_heap_obj, value_bit);
     RestartIfNotMarking();
   }
   return is_compacting_ && is_black;
 }
 
@@ skipping 77 matching lines @@
 
 void IncrementalMarking::WhiteToGreyAndPush(HeapObject* obj, MarkBit mark_bit) {
   Marking::WhiteToGrey(mark_bit);
   heap_->mark_compact_collector()->marking_deque()->Push(obj);
 }
 
 
 static void MarkObjectGreyDoNotEnqueue(Object* obj) {
   if (obj->IsHeapObject()) {
     HeapObject* heap_obj = HeapObject::cast(obj);
-    MarkBit mark_bit = Marking::MarkBitFrom(HeapObject::cast(obj));
+    MarkBit mark_bit = ObjectMarking::MarkBitFrom(HeapObject::cast(obj));
     if (Marking::IsBlack(mark_bit)) {
       MemoryChunk::IncrementLiveBytesFromGC(heap_obj, -heap_obj->Size());
     }
     Marking::AnyToGrey(mark_bit);
   }
 }
 
+void IncrementalMarking::TransferMark(Heap* heap, Address old_start,
+                                      Address new_start) {
+  // This is only used when resizing an object.
+  DCHECK(MemoryChunk::FromAddress(old_start) ==
+         MemoryChunk::FromAddress(new_start));
+
+  if (!heap->incremental_marking()->IsMarking() ||
+      Page::FromAddress(old_start)->IsFlagSet(Page::BLACK_PAGE))
+    return;
+
+  // If the mark doesn't move, we don't check the color of the object.
+  // It doesn't matter whether the object is black, since it hasn't changed
+  // size, so the adjustment to the live data count will be zero anyway.
+  if (old_start == new_start) return;
+
+  MarkBit new_mark_bit = ObjectMarking::MarkBitFrom(new_start);
+  MarkBit old_mark_bit = ObjectMarking::MarkBitFrom(old_start);
+
+#ifdef DEBUG
+  Marking::ObjectColor old_color = Marking::Color(old_mark_bit);
+#endif
+
+  if (Marking::IsBlack(old_mark_bit)) {
+    Marking::BlackToWhite(old_mark_bit);
+    Marking::MarkBlack(new_mark_bit);
+    return;
+  } else if (Marking::IsGrey(old_mark_bit)) {
+    Marking::GreyToWhite(old_mark_bit);
+    heap->incremental_marking()->WhiteToGreyAndPush(
+        HeapObject::FromAddress(new_start), new_mark_bit);
+    heap->incremental_marking()->RestartIfNotMarking();
+  }
+
+#ifdef DEBUG
+  Marking::ObjectColor new_color = Marking::Color(new_mark_bit);
+  DCHECK(new_color == old_color);
+#endif
+}
 
 static inline void MarkBlackOrKeepBlack(HeapObject* heap_object,
                                         MarkBit mark_bit, int size) {
   DCHECK(!Marking::IsImpossible(mark_bit));
   if (Marking::IsBlack(mark_bit)) return;
   Marking::MarkBlack(mark_bit);
   MemoryChunk::IncrementLiveBytesFromGC(heap_object, size);
 }
 
-
 class IncrementalMarkingMarkingVisitor
     : public StaticMarkingVisitor<IncrementalMarkingMarkingVisitor> {
  public:
   static void Initialize() {
     StaticMarkingVisitor<IncrementalMarkingMarkingVisitor>::Initialize();
     table_.Register(kVisitFixedArray, &VisitFixedArrayIncremental);
     table_.Register(kVisitNativeContext, &VisitNativeContextIncremental);
     table_.Register(kVisitJSRegExp, &VisitJSRegExp);
     if (FLAG_track_gc_object_stats) {
       IncrementalMarkingObjectStatsVisitor::Initialize(&table_);
@@ skipping 26 matching lines @@
       do {
         VisitPointers(heap, object, HeapObject::RawField(object, start_offset),
                       HeapObject::RawField(object, end_offset));
         start_offset = end_offset;
         end_offset = Min(object_size, end_offset + kProgressBarScanningChunk);
         scan_until_end =
             heap->mark_compact_collector()->marking_deque()->IsFull();
       } while (scan_until_end && start_offset < object_size);
       chunk->set_progress_bar(start_offset);
       if (start_offset < object_size) {
-        if (Marking::IsGrey(Marking::MarkBitFrom(object))) {
+        if (Marking::IsGrey(ObjectMarking::MarkBitFrom(object))) {
           heap->mark_compact_collector()->marking_deque()->Unshift(object);
         } else {
-          DCHECK(Marking::IsBlack(Marking::MarkBitFrom(object)));
+          DCHECK(Marking::IsBlack(ObjectMarking::MarkBitFrom(object)));
           heap->mark_compact_collector()->UnshiftBlack(object);
         }
         heap->incremental_marking()->NotifyIncompleteScanOfObject(
             object_size - (start_offset - already_scanned_offset));
       }
     } else {
       FixedArrayVisitor::Visit(map, object);
     }
   }
 
@@ skipping 31 matching lines @@
 
   // Marks the object grey and pushes it on the marking stack.
   INLINE(static void MarkObject(Heap* heap, Object* obj)) {
     IncrementalMarking::MarkObject(heap, HeapObject::cast(obj));
   }
 
   // Marks the object black without pushing it on the marking stack.
   // Returns true if object needed marking and false otherwise.
   INLINE(static bool MarkObjectWithoutPush(Heap* heap, Object* obj)) {
     HeapObject* heap_object = HeapObject::cast(obj);
-    MarkBit mark_bit = Marking::MarkBitFrom(heap_object);
+    MarkBit mark_bit = ObjectMarking::MarkBitFrom(heap_object);
     if (Marking::IsWhite(mark_bit)) {
       Marking::MarkBlack(mark_bit);
       MemoryChunk::IncrementLiveBytesFromGC(heap_object, heap_object->Size());
       return true;
     }
     return false;
   }
 };
 
 void IncrementalMarking::IterateBlackObject(HeapObject* object) {
-  if (IsMarking() && Marking::IsBlack(Marking::MarkBitFrom(object))) {
+  if (IsMarking() && Marking::IsBlack(ObjectMarking::MarkBitFrom(object))) {
     Page* page = Page::FromAddress(object->address());
     if ((page->owner() != nullptr) && (page->owner()->identity() == LO_SPACE)) {
       // IterateBlackObject requires us to visit the whole object.
       page->ResetProgressBar();
     }
     IncrementalMarkingMarkingVisitor::IterateBody(object->map(), object);
   }
 }
 
 class IncrementalMarkingRootMarkingVisitor : public ObjectVisitor {
@@ skipping 353 matching lines @@
 }
 
 
 bool ShouldRetainMap(Map* map, int age) {
   if (age == 0) {
     // The map has aged. Do not retain this map.
     return false;
   }
   Object* constructor = map->GetConstructor();
   if (!constructor->IsHeapObject() ||
-      Marking::IsWhite(Marking::MarkBitFrom(HeapObject::cast(constructor)))) {
+      Marking::IsWhite(
+          ObjectMarking::MarkBitFrom(HeapObject::cast(constructor)))) {
     // The constructor is dead, no new objects with this map can
     // be created. Do not retain this map.
     return false;
   }
   return true;
 }
 
 
 void IncrementalMarking::RetainMaps() {
   // Do not retain dead maps if flag disables it or there is
   // - memory pressure (reduce_memory_footprint_),
   // - GC is requested by tests or dev-tools (abort_incremental_marking_).
   bool map_retaining_is_disabled = heap()->ShouldReduceMemory() ||
                                    heap()->ShouldAbortIncrementalMarking() ||
                                    FLAG_retain_maps_for_n_gc == 0;
   ArrayList* retained_maps = heap()->retained_maps();
   int length = retained_maps->Length();
   // The number_of_disposed_maps separates maps in the retained_maps
   // array that were created before and after context disposal.
   // We do not age and retain disposed maps to avoid memory leaks.
   int number_of_disposed_maps = heap()->number_of_disposed_maps_;
   for (int i = 0; i < length; i += 2) {
     DCHECK(retained_maps->Get(i)->IsWeakCell());
     WeakCell* cell = WeakCell::cast(retained_maps->Get(i));
     if (cell->cleared()) continue;
     int age = Smi::cast(retained_maps->Get(i + 1))->value();
     int new_age;
     Map* map = Map::cast(cell->value());
-    MarkBit map_mark = Marking::MarkBitFrom(map);
+    MarkBit map_mark = ObjectMarking::MarkBitFrom(map);
     if (i >= number_of_disposed_maps && !map_retaining_is_disabled &&
         Marking::IsWhite(map_mark)) {
       if (ShouldRetainMap(map, age)) {
         MarkObject(heap(), map);
       }
       Object* prototype = map->prototype();
       if (age > 0 && prototype->IsHeapObject() &&
-          Marking::IsWhite(Marking::MarkBitFrom(HeapObject::cast(prototype)))) {
+          Marking::IsWhite(
+              ObjectMarking::MarkBitFrom(HeapObject::cast(prototype)))) {
         // The prototype is not marked, age the map.
         new_age = age - 1;
       } else {
         // The prototype and the constructor are marked, this map keeps only
         // transition tree alive, not JSObjects. Do not age the map.
         new_age = age;
       }
     } else {
       new_age = FLAG_retain_maps_for_n_gc;
     }
@@ skipping 91 matching lines @@
       // entries will not point to forwarding addresses. Hence, we can discard
       // them.
       if (map_word.IsForwardingAddress()) {
         HeapObject* dest = map_word.ToForwardingAddress();
         if (Page::FromAddress(dest->address())->IsFlagSet(Page::BLACK_PAGE))
           continue;
         array[new_top] = dest;
         new_top = ((new_top + 1) & mask);
         DCHECK(new_top != marking_deque->bottom());
 #ifdef DEBUG
-        MarkBit mark_bit = Marking::MarkBitFrom(obj);
+        MarkBit mark_bit = ObjectMarking::MarkBitFrom(obj);
         DCHECK(Marking::IsGrey(mark_bit) ||
                (obj->IsFiller() && Marking::IsWhite(mark_bit)));
 #endif
       }
     } else if (obj->map() != filler_map) {
       // Skip one word filler objects that appear on the
       // stack when we perform in place array shift.
       array[new_top] = obj;
       new_top = ((new_top + 1) & mask);
       DCHECK(new_top != marking_deque->bottom());
 #ifdef DEBUG
-      MarkBit mark_bit = Marking::MarkBitFrom(obj);
+      MarkBit mark_bit = ObjectMarking::MarkBitFrom(obj);
       MemoryChunk* chunk = MemoryChunk::FromAddress(obj->address());
       DCHECK(Marking::IsGrey(mark_bit) ||
              (obj->IsFiller() && Marking::IsWhite(mark_bit)) ||
              (chunk->IsFlagSet(MemoryChunk::HAS_PROGRESS_BAR) &&
               Marking::IsBlack(mark_bit)));
 #endif
     }
   }
   marking_deque->set_top(new_top);
 }
 
 
 void IncrementalMarking::VisitObject(Map* map, HeapObject* obj, int size) {
   MarkObject(heap_, map);
 
   IncrementalMarkingMarkingVisitor::IterateBody(map, obj);
 
-  MarkBit mark_bit = Marking::MarkBitFrom(obj);
+  MarkBit mark_bit = ObjectMarking::MarkBitFrom(obj);
 #if ENABLE_SLOW_DCHECKS
   MemoryChunk* chunk = MemoryChunk::FromAddress(obj->address());
   SLOW_DCHECK(Marking::IsGrey(mark_bit) ||
               (obj->IsFiller() && Marking::IsWhite(mark_bit)) ||
               (chunk->IsFlagSet(MemoryChunk::HAS_PROGRESS_BAR) &&
                Marking::IsBlack(mark_bit)));
 #endif
   MarkBlackOrKeepBlack(obj, mark_bit, size);
 }
 
 
 void IncrementalMarking::MarkObject(Heap* heap, HeapObject* obj) {
-  MarkBit mark_bit = Marking::MarkBitFrom(obj);
+  MarkBit mark_bit = ObjectMarking::MarkBitFrom(obj);
   if (Marking::IsWhite(mark_bit)) {
     heap->incremental_marking()->WhiteToGreyAndPush(obj, mark_bit);
   }
 }
 
 
 intptr_t IncrementalMarking::ProcessMarkingDeque(intptr_t bytes_to_process) {
   intptr_t bytes_processed = 0;
   Map* one_pointer_filler_map = heap_->one_pointer_filler_map();
   Map* two_pointer_filler_map = heap_->two_pointer_filler_map();
@@ skipping 66 matching lines @@
     }
   }
 
   Object* context = heap_->native_contexts_list();
   while (!context->IsUndefined(heap_->isolate())) {
     // GC can happen when the context is not fully initialized,
     // so the cache can be undefined.
     HeapObject* cache = HeapObject::cast(
         Context::cast(context)->get(Context::NORMALIZED_MAP_CACHE_INDEX));
     if (!cache->IsUndefined(heap_->isolate())) {
-      MarkBit mark_bit = Marking::MarkBitFrom(cache);
+      MarkBit mark_bit = ObjectMarking::MarkBitFrom(cache);
       if (Marking::IsGrey(mark_bit)) {
         Marking::GreyToBlack(mark_bit);
         MemoryChunk::IncrementLiveBytesFromGC(cache, cache->Size());
       }
     }
     context = Context::cast(context)->next_context_link();
   }
 }
 
 
@@ skipping 295 matching lines @@
 void IncrementalMarking::IncrementIdleMarkingDelayCounter() {
   idle_marking_delay_counter_++;
 }
 
 
 void IncrementalMarking::ClearIdleMarkingDelayCounter() {
   idle_marking_delay_counter_ = 0;
 }
 }  // namespace internal
 }  // namespace v8