[heap] Provide ObjectMarking with marking transitions

src/heap/spaces.cc

 // Copyright 2011 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/spaces.h"
 
 #include <utility>
 
 #include "src/base/bits.h"
 #include "src/base/platform/platform.h"
@@ skipping 1441 matching lines @@
 
       // Perform space-specific object verification.
       VerifyObject(object);
 
       // The object itself should look OK.
       object->ObjectVerify();
 
       // All the interior pointers should be contained in the heap.
       int size = object->Size();
       object->IterateBody(map->instance_type(), size, visitor);
-      if (Marking::IsBlack(ObjectMarking::MarkBitFrom(object))) {
+      if (ObjectMarking::IsBlack(object)) {
         black_size += size;
       }
 
       CHECK(object->address() + size <= top);
       end_of_previous_object = object->address() + size;
     }
     CHECK_LE(black_size, page->LiveBytes());
   }
   CHECK(allocation_pointer_found_in_space);
 }
@@ skipping 1510 matching lines @@
     reinterpret_cast<Object**>(object->address())[0] =
         heap()->fixed_array_map();
     reinterpret_cast<Object**>(object->address())[1] = Smi::kZero;
   }
 
   heap()->StartIncrementalMarkingIfAllocationLimitIsReached(Heap::kNoGCFlags,
                                                             kNoGCCallbackFlags);
   AllocationStep(object->address(), object_size);
 
   if (heap()->incremental_marking()->black_allocation()) {
-    Marking::MarkBlack(ObjectMarking::MarkBitFrom(object));
+    // We cannot use ObjectMarking here as the object still lacks a size.
+    Marking::WhiteToBlack(ObjectMarking::MarkBitFrom(object));
     MemoryChunk::IncrementLiveBytes(object, object_size);
   }
   return object;
 }
 
 
 size_t LargeObjectSpace::CommittedPhysicalMemory() {
   // On a platform that provides lazy committing of memory, we over-account
   // the actually committed memory. There is no easy way right now to support
   // precise accounting of committed memory in large object space.
@@ skipping 28 matching lines @@
     }
   }
   return NULL;
 }
 
 
 void LargeObjectSpace::ClearMarkingStateOfLiveObjects() {
   LargePage* current = first_page_;
   while (current != NULL) {
     HeapObject* object = current->GetObject();
-    MarkBit mark_bit = ObjectMarking::MarkBitFrom(object);
-    DCHECK(Marking::IsBlack(mark_bit));
-    Marking::BlackToWhite(mark_bit);
+    DCHECK(ObjectMarking::IsBlack(object));
+    ObjectMarking::BlackToWhite(object);
     Page::FromAddress(object->address())->ResetProgressBar();
     Page::FromAddress(object->address())->ResetLiveBytes();
     current = current->next_page();
   }
 }
 
 void LargeObjectSpace::InsertChunkMapEntries(LargePage* page) {
   // Register all MemoryChunk::kAlignment-aligned chunks covered by
   // this large page in the chunk map.
   uintptr_t start = reinterpret_cast<uintptr_t>(page) / MemoryChunk::kAlignment;
@@ skipping 24 matching lines @@
   for (uintptr_t key = start; key <= limit; key++) {
     chunk_map_.Remove(reinterpret_cast<void*>(key), static_cast<uint32_t>(key));
   }
 }
 
 void LargeObjectSpace::FreeUnmarkedObjects() {
   LargePage* previous = NULL;
   LargePage* current = first_page_;
   while (current != NULL) {
     HeapObject* object = current->GetObject();
-    MarkBit mark_bit = ObjectMarking::MarkBitFrom(object);
-    DCHECK(!Marking::IsGrey(mark_bit));
-    if (Marking::IsBlack(mark_bit)) {
+    DCHECK(!ObjectMarking::IsGrey(object));
+    if (ObjectMarking::IsBlack(object)) {
       Address free_start;
       if ((free_start = current->GetAddressToShrink()) != 0) {
         // TODO(hpayer): Perform partial free concurrently.
         current->ClearOutOfLiveRangeSlots(free_start);
         RemoveChunkMapEntries(current, free_start);
         heap()->memory_allocator()->PartialFreeMemory(current, free_start);
       }
       previous = current;
       current = current->next_page();
     } else {
@@ skipping 114 matching lines @@
 
 void Page::Print() {
   // Make a best-effort to print the objects in the page.
   PrintF("Page@%p in %s\n", static_cast<void*>(this->address()),
          AllocationSpaceName(this->owner()->identity()));
   printf(" --------------------------------------\n");
   HeapObjectIterator objects(this);
   unsigned mark_size = 0;
   for (HeapObject* object = objects.Next(); object != NULL;
        object = objects.Next()) {
-    bool is_marked = Marking::IsBlackOrGrey(ObjectMarking::MarkBitFrom(object));
+    bool is_marked = ObjectMarking::IsBlackOrGrey(object);
     PrintF(" %c ", (is_marked ? '!' : ' '));  // Indent a little.
     if (is_marked) {
       mark_size += object->Size();
     }
     object->ShortPrint();
     PrintF("\n");
   }
   printf(" --------------------------------------\n");
   printf(" Marked: %x, LiveCount: %x\n", mark_size, LiveBytes());
 }
 
 #endif  // DEBUG
 }  // namespace internal
 }  // namespace v8