[heap] Use atomic marking operations in incremental marking if

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/concurrent-marking.h"
@@ skipping 25 matching lines @@
       was_activated_(false),
       black_allocation_(false),
       finalize_marking_completed_(false),
       trace_wrappers_toggle_(false),
       request_type_(NONE),
       new_generation_observer_(*this, kAllocatedThreshold),
       old_generation_observer_(*this, kAllocatedThreshold) {}
 
 bool IncrementalMarking::BaseRecordWrite(HeapObject* obj, Object* value) {
   HeapObject* value_heap_obj = HeapObject::cast(value);
-  DCHECK(!ObjectMarking::IsImpossible(value_heap_obj,
-                                      marking_state(value_heap_obj)));
-  DCHECK(!ObjectMarking::IsImpossible(obj, marking_state(obj)));
-  const bool is_black = ObjectMarking::IsBlack(obj, marking_state(obj));
+  DCHECK(!ObjectMarking::IsImpossible<kAtomicity>(
+      value_heap_obj, marking_state(value_heap_obj)));
+  DCHECK(!ObjectMarking::IsImpossible<kAtomicity>(obj, marking_state(obj)));
+  const bool is_black =
+      ObjectMarking::IsBlack<kAtomicity>(obj, marking_state(obj));
 
   if (is_black && WhiteToGreyAndPush(value_heap_obj)) {
     RestartIfNotMarking();
   }
   return is_compacting_ && is_black;
 }
 
 
 void IncrementalMarking::RecordWriteSlow(HeapObject* obj, Object** slot,
                                          Object* value) {
@@ skipping 53 matching lines @@
 
 void IncrementalMarking::RecordWriteIntoCodeSlow(Code* host, RelocInfo* rinfo,
                                                  Object* value) {
   if (BaseRecordWrite(host, value)) {
     // Object is not going to be rescanned.  We need to record the slot.
     heap_->mark_compact_collector()->RecordRelocSlot(host, rinfo, value);
   }
 }
 
 bool IncrementalMarking::WhiteToGreyAndPush(HeapObject* obj) {
-  if (ObjectMarking::WhiteToGrey(obj, marking_state(obj))) {
+  if (ObjectMarking::WhiteToGrey<kAtomicity>(obj, marking_state(obj))) {
     marking_deque()->Push(obj);
     return true;
   }
   return false;
 }
 
 void IncrementalMarking::TransferMark(Heap* heap, HeapObject* from,
                                       HeapObject* to) {
   DCHECK(MemoryChunk::FromAddress(from->address())->SweepingDone());
   // This is only used when resizing an object.
   DCHECK(MemoryChunk::FromAddress(from->address()) ==
          MemoryChunk::FromAddress(to->address()));
 
   if (!IsMarking()) 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 (from == to) return;
 
   MarkBit new_mark_bit = ObjectMarking::MarkBitFrom(to, marking_state(to));
   MarkBit old_mark_bit = ObjectMarking::MarkBitFrom(from, marking_state(from));
 
-  if (Marking::IsBlack(old_mark_bit)) {
+  if (Marking::IsBlack<kAtomicity>(old_mark_bit)) {
     if (from->address() + kPointerSize == to->address()) {
       // The old and the new markbits overlap. The |to| object has the
       // grey color. To make it black, we need to set second bit.
-      DCHECK(new_mark_bit.Get());
-      new_mark_bit.Next().Set();
+      DCHECK(new_mark_bit.Get<kAtomicity>());
+      new_mark_bit.Next().Set<kAtomicity>();
     } else {
-      bool success = Marking::WhiteToBlack(new_mark_bit);
+      bool success = Marking::WhiteToBlack<kAtomicity>(new_mark_bit);
       DCHECK(success);
       USE(success);
     }
-  } else if (Marking::IsGrey(old_mark_bit)) {
+  } else if (Marking::IsGrey<kAtomicity>(old_mark_bit)) {
     if (from->address() + kPointerSize == to->address()) {
       // The old and the new markbits overlap. The |to| object has the
       // white color. To make it black, we need to set both bits.
       // Note that Marking::WhiteToGrey does not work here because
       // old_mark_bit.Next() can be set by the concurrent marker at any time.
-      new_mark_bit.Set();
-      new_mark_bit.Next().Set();
+      new_mark_bit.Set<kAtomicity>();
+      new_mark_bit.Next().Set<kAtomicity>();
     } else {
-      bool success = Marking::WhiteToGrey(new_mark_bit);
+      bool success = Marking::WhiteToGrey<kAtomicity>(new_mark_bit);
       DCHECK(success);
       USE(success);
       marking_deque()->Push(to);
       RestartIfNotMarking();
     }
   }
 }
 
 class IncrementalMarkingMarkingVisitor
     : public StaticMarkingVisitor<IncrementalMarkingMarkingVisitor> {
@@ skipping 25 matching lines @@
       bool scan_until_end = false;
       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->incremental_marking()->marking_deque()->IsFull();
       } while (scan_until_end && start_offset < object_size);
       chunk->set_progress_bar(start_offset);
       if (start_offset < object_size) {
-        if (ObjectMarking::IsGrey(
+        if (ObjectMarking::IsGrey<IncrementalMarking::kAtomicity>(
                 object, heap->incremental_marking()->marking_state(object))) {
           heap->incremental_marking()->marking_deque()->Unshift(object);
         } else {
-          DCHECK(ObjectMarking::IsBlack(
+          DCHECK(ObjectMarking::IsBlack<IncrementalMarking::kAtomicity>(
               object, heap->incremental_marking()->marking_state(object)));
           heap->mark_compact_collector()->UnshiftBlack(object);
         }
         heap->incremental_marking()->NotifyIncompleteScanOfObject(
             object_size - (start_offset - already_scanned_offset));
       }
     } else {
       FixedArrayVisitor::Visit(map, object);
     }
   }
 
   static void VisitNativeContextIncremental(Map* map, HeapObject* object) {
     Context* context = Context::cast(object);
 
     // We will mark cache black with a separate pass when we finish marking.
     // Note that GC can happen when the context is not fully initialized,
     // so the cache can be undefined.
     Object* cache = context->get(Context::NORMALIZED_MAP_CACHE_INDEX);
     if (!cache->IsUndefined(map->GetIsolate())) {
       if (cache->IsHeapObject()) {
         HeapObject* heap_obj = HeapObject::cast(cache);
         // Mark the object grey if it is white, do not enque it into the marking
         // deque.
         Heap* heap = map->GetHeap();
-        bool ignored = ObjectMarking::WhiteToGrey(
-            heap_obj, heap->incremental_marking()->marking_state(heap_obj));
+        bool ignored =
+            ObjectMarking::WhiteToGrey<IncrementalMarking::kAtomicity>(
+                heap_obj, heap->incremental_marking()->marking_state(heap_obj));
         USE(ignored);
       }
     }
     VisitNativeContext(map, context);
   }
 
   INLINE(static void VisitPointer(Heap* heap, HeapObject* object, Object** p)) {
     Object* target = *p;
     if (target->IsHeapObject()) {
       heap->mark_compact_collector()->RecordSlot(object, p, target);
@@ skipping 14 matching lines @@
 
   // Marks the object grey and pushes it on the marking stack.
   INLINE(static void MarkObject(Heap* heap, Object* obj)) {
     heap->incremental_marking()->WhiteToGreyAndPush(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);
-    return ObjectMarking::WhiteToBlack(
+    return ObjectMarking::WhiteToBlack<IncrementalMarking::kAtomicity>(
         heap_object, heap->incremental_marking()->marking_state(heap_object));
   }
 };
 
 void IncrementalMarking::IterateBlackObject(HeapObject* object) {
-  if (IsMarking() && ObjectMarking::IsBlack(object, marking_state(object))) {
+  if (IsMarking() &&
+      ObjectMarking::IsBlack<kAtomicity>(object, marking_state(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();
     }
     Map* map = object->map();
     WhiteToGreyAndPush(map);
     IncrementalMarkingMarkingVisitor::IterateBody(map, object);
   }
 }
@@ skipping 336 matching lines @@
   Object* weak_cell_obj = heap()->encountered_weak_cells();
   Object* weak_cell_head = Smi::kZero;
   WeakCell* prev_weak_cell_obj = NULL;
   while (weak_cell_obj != Smi::kZero) {
     WeakCell* weak_cell = reinterpret_cast<WeakCell*>(weak_cell_obj);
     // We do not insert cleared weak cells into the list, so the value
     // cannot be a Smi here.
     HeapObject* value = HeapObject::cast(weak_cell->value());
     // Remove weak cells with live objects from the list, they do not need
     // clearing.
-    if (ObjectMarking::IsBlackOrGrey(value, marking_state(value))) {
+    if (ObjectMarking::IsBlackOrGrey<kAtomicity>(value, marking_state(value))) {
       // Record slot, if value is pointing to an evacuation candidate.
       Object** slot = HeapObject::RawField(weak_cell, WeakCell::kValueOffset);
       heap_->mark_compact_collector()->RecordSlot(weak_cell, slot, *slot);
       // Remove entry somewhere after top.
       if (prev_weak_cell_obj != NULL) {
         prev_weak_cell_obj->set_next(weak_cell->next());
       }
       weak_cell_obj = weak_cell->next();
       weak_cell->clear_next(the_hole_value);
     } else {
@@ skipping 10 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();
   Heap* heap = map->GetHeap();
   if (!constructor->IsHeapObject() ||
-      ObjectMarking::IsWhite(HeapObject::cast(constructor),
-                             heap->incremental_marking()->marking_state(
-                                 HeapObject::cast(constructor)))) {
+      ObjectMarking::IsWhite<IncrementalMarking::kAtomicity>(
+          HeapObject::cast(constructor),
+          heap->incremental_marking()->marking_state(
+              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());
     if (i >= number_of_disposed_maps && !map_retaining_is_disabled &&
-        ObjectMarking::IsWhite(map, marking_state(map))) {
+        ObjectMarking::IsWhite<kAtomicity>(map, marking_state(map))) {
       if (ShouldRetainMap(map, age)) {
         WhiteToGreyAndPush(map);
       }
       Object* prototype = map->prototype();
       if (age > 0 && prototype->IsHeapObject() &&
-          ObjectMarking::IsWhite(HeapObject::cast(prototype),
-                                 marking_state(HeapObject::cast(prototype)))) {
+          ObjectMarking::IsWhite<kAtomicity>(
+              HeapObject::cast(prototype),
+              marking_state(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 70 matching lines @@
       MapWord map_word = obj->map_word();
       if (!map_word.IsForwardingAddress()) {
         // There may be objects on the marking deque that do not exist anymore,
         // e.g. left trimmed objects or objects from the root set (frames).
         // If these object are dead at scavenging time, their marking deque
         // entries will not point to forwarding addresses. Hence, we can discard
         // them.
         return nullptr;
       }
       HeapObject* dest = map_word.ToForwardingAddress();
-      if (ObjectMarking::IsBlack(dest, marking_state(dest))) {
+      if (ObjectMarking::IsBlack<kAtomicity>(dest, marking_state(dest))) {
         // The object is already processed by the marker.
         return nullptr;
       }
-      DCHECK(
-          ObjectMarking::IsGrey(obj, marking_state(obj)) ||
-          (obj->IsFiller() && ObjectMarking::IsWhite(obj, marking_state(obj))));
+      DCHECK(ObjectMarking::IsGrey<kAtomicity>(obj, marking_state(obj)) ||
+             (obj->IsFiller() &&
+              ObjectMarking::IsWhite<kAtomicity>(obj, marking_state(obj))));
       return dest;
     } else {
-      DCHECK(ObjectMarking::IsGrey(obj, marking_state(obj)) ||
+      DCHECK(ObjectMarking::IsGrey<kAtomicity>(obj, marking_state(obj)) ||
              (obj->IsFiller() &&
-              ObjectMarking::IsWhite(obj, marking_state(obj))) ||
+              ObjectMarking::IsWhite<kAtomicity>(obj, marking_state(obj))) ||
              (MemoryChunk::FromAddress(obj->address())
                   ->IsFlagSet(MemoryChunk::HAS_PROGRESS_BAR) &&
-              ObjectMarking::IsBlack(obj, marking_state(obj))));
+              ObjectMarking::IsBlack<kAtomicity>(obj, marking_state(obj))));
       // Skip one word filler objects that appear on the
       // stack when we perform in place array shift.
       return (obj->map() == filler_map) ? nullptr : obj;
     }
   });
 }
 
 
 void IncrementalMarking::VisitObject(Map* map, HeapObject* obj, int size) {
   WhiteToGreyAndPush(map);
 
   IncrementalMarkingMarkingVisitor::IterateBody(map, obj);
 
 #if ENABLE_SLOW_DCHECKS
   MarkBit mark_bit = ObjectMarking::MarkBitFrom(obj, marking_state(obj));
   MemoryChunk* chunk = MemoryChunk::FromAddress(obj->address());
-  SLOW_DCHECK(Marking::IsGrey(mark_bit) ||
+  SLOW_DCHECK(Marking::IsGrey<kAtomicity>(mark_bit) ||
               (chunk->IsFlagSet(MemoryChunk::HAS_PROGRESS_BAR) &&
-               Marking::IsBlack(mark_bit)));
+               Marking::IsBlack<kAtomicity>(mark_bit)));
 #endif
-  ObjectMarking::GreyToBlack(obj, marking_state(obj));
+  ObjectMarking::GreyToBlack<kAtomicity>(obj, marking_state(obj));
 }
 
 intptr_t IncrementalMarking::ProcessMarkingDeque(
     intptr_t bytes_to_process, ForceCompletionAction completion) {
   intptr_t bytes_processed = 0;
   while (!marking_deque()->IsEmpty() && (bytes_processed < bytes_to_process ||
                                          completion == FORCE_COMPLETION)) {
     HeapObject* obj = marking_deque()->Pop();
 
     // Left trimming may result in white, grey, or black filler objects on the
     // marking deque. Ignore these objects.
     if (obj->IsFiller()) {
-      DCHECK(!ObjectMarking::IsImpossible(obj, marking_state(obj)));
+      DCHECK(!ObjectMarking::IsImpossible<kAtomicity>(obj, marking_state(obj)));
       continue;
     }
 
     Map* map = obj->map();
     int size = obj->SizeFromMap(map);
     unscanned_bytes_of_large_object_ = 0;
     VisitObject(map, obj, size);
     bytes_processed += size - unscanned_bytes_of_large_object_;
   }
   // Report all found wrappers to the embedder. This is necessary as the
@@ skipping 35 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())) {
       // Mark the cache black if it is grey.
-      bool ignored = ObjectMarking::GreyToBlack(cache, marking_state(cache));
+      bool ignored =
+          ObjectMarking::GreyToBlack<kAtomicity>(cache, marking_state(cache));
       USE(ignored);
     }
     context = Context::cast(context)->next_context_link();
   }
 }
 
 
 void IncrementalMarking::Stop() {
   if (IsStopped()) return;
   if (FLAG_trace_incremental_marking) {
@@ skipping 260 matching lines @@
   idle_marking_delay_counter_++;
 }
 
 
 void IncrementalMarking::ClearIdleMarkingDelayCounter() {
   idle_marking_delay_counter_ = 0;
 }
 
 }  // namespace internal
 }  // namespace v8