[heap] Black areas are created for both linear and free list allocations.

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 815 matching lines @@
         filler->address(),
         static_cast<int>(area_end() - filler->address() - unused),
         ClearRecordedSlots::kNo);
     heap()->memory_allocator()->ShrinkChunk(this, unused);
     CHECK(filler->IsFiller());
     CHECK_EQ(filler->address() + filler->Size(), area_end());
   }
   return unused;
 }
 
+void Page::CreateBlackArea(Address start, Address end) {
+  DCHECK(heap()->incremental_marking()->black_allocation());
+  DCHECK_EQ(Page::FromAddress(start), this);
+  DCHECK_NE(start, end);
+  DCHECK_EQ(Page::FromAddress(end - 1), this);
+  markbits()->SetRange(AddressToMarkbitIndex(start),
+                       AddressToMarkbitIndex(end));
+  IncrementLiveBytes(static_cast<int>(end - start));
+}
+
 void MemoryAllocator::PartialFreeMemory(MemoryChunk* chunk,
                                         Address start_free) {
   // We do not allow partial shrink for code.
   DCHECK(chunk->executable() == NOT_EXECUTABLE);
 
   intptr_t size;
   base::VirtualMemory* reservation = chunk->reserved_memory();
   DCHECK(reservation->IsReserved());
   size = static_cast<intptr_t>(reservation->size());
 
@@ skipping 489 matching lines @@
 void PagedSpace::ResetFreeListStatistics() {
   for (Page* page : *this) {
     page->ResetFreeListStatistics();
   }
 }
 
 void PagedSpace::SetAllocationInfo(Address top, Address limit) {
   SetTopAndLimit(top, limit);
   if (top != nullptr && top != limit &&
       heap()->incremental_marking()->black_allocation()) {
-    Page* page = Page::FromAllocationAreaAddress(top);
-    page->markbits()->SetRange(page->AddressToMarkbitIndex(top),
-                               page->AddressToMarkbitIndex(limit));
-    page->IncrementLiveBytes(static_cast<int>(limit - top));
+    Page::FromAllocationAreaAddress(top)->CreateBlackArea(top, limit);
   }
 }
 
 void PagedSpace::MarkAllocationInfoBlack() {
   DCHECK(heap()->incremental_marking()->black_allocation());
   Address current_top = top();
   Address current_limit = limit();
   if (current_top != nullptr && current_top != current_limit) {
-    Page* page = Page::FromAllocationAreaAddress(current_top);
-    page->markbits()->SetRange(page->AddressToMarkbitIndex(current_top),
-                               page->AddressToMarkbitIndex(current_limit));
-    page->IncrementLiveBytes(static_cast<int>(current_limit - current_top));
+    Page::FromAllocationAreaAddress(current_top)
+        ->CreateBlackArea(current_top, current_limit);
   }
 }
 
 // Empty space allocation info, returning unused area to free list.
 void PagedSpace::EmptyAllocationInfo() {
   // Mark the old linear allocation area with a free space map so it can be
   // skipped when scanning the heap.
   Address current_top = top();
   Address current_limit = limit();
   if (current_top == nullptr) {
@@ skipping 1858 matching lines @@
     object->ShortPrint();
     PrintF("\n");
   }
   printf(" --------------------------------------\n");
   printf(" Marked: %x, LiveCount: %x\n", mark_size, LiveBytes());
 }
 
 #endif  // DEBUG
 }  // namespace internal
 }  // namespace v8