Fix OOM bug 3976.

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/v8.h"
 
 #include "src/base/bits.h"
 #include "src/base/platform/platform.h"
 #include "src/full-codegen.h"
 #include "src/heap/mark-compact.h"
@@ skipping 1001 matching lines @@
 
   UNREACHABLE();
   return Smi::FromInt(0);
 }
 
 
 bool PagedSpace::CanExpand() {
   DCHECK(max_capacity_ % AreaSize() == 0);
   DCHECK(Capacity() <= heap()->MaxOldGenerationSize());
   DCHECK(heap()->CommittedOldGenerationMemory() <=
-         heap()->MaxOldGenerationSize());
+         heap()->MaxOldGenerationSize() +
+             PagedSpace::MaxEmergencyMemoryAllocated());
 
   // Are we going to exceed capacity for this space?
   if (!heap()->CanExpandOldGeneration(Page::kPageSize)) return false;
 
   return true;
 }
 
 
 bool PagedSpace::Expand() {
   if (!CanExpand()) return false;
 
   intptr_t size = AreaSize();
 
   if (anchor_.next_page() == &anchor_) {
     size = Snapshot::SizeOfFirstPage(heap()->isolate(), identity());
   }
 
   Page* p = heap()->isolate()->memory_allocator()->AllocatePage(size, this,
                                                                 executable());
   if (p == NULL) return false;
 
   // Pages created during bootstrapping may contain immortal immovable objects.
   if (!heap()->deserialization_complete()) p->MarkNeverEvacuate();
 
   DCHECK(Capacity() <= heap()->MaxOldGenerationSize());
   DCHECK(heap()->CommittedOldGenerationMemory() <=
-         heap()->MaxOldGenerationSize());
+         heap()->MaxOldGenerationSize() +
+             PagedSpace::MaxEmergencyMemoryAllocated());
 
   p->InsertAfter(anchor_.prev_page());
 
   return true;
 }
 
 
 int PagedSpace::CountTotalPages() {
   PageIterator it(this);
   int count = 0;
@@ skipping 61 matching lines @@
     heap()->isolate()->memory_allocator()->Free(page);
   } else {
     heap()->QueueMemoryChunkForFree(page);
   }
 
   DCHECK(Capacity() > 0);
   accounting_stats_.ShrinkSpace(AreaSize());
 }
 
 
+intptr_t PagedSpace::MaxEmergencyMemoryAllocated() {
+  // New space and large object space.
+  static const int spaces_without_emergency_memory = 2;
+  static const int spaces_with_emergency_memory =
+      LAST_SPACE - FIRST_SPACE + 1 - spaces_without_emergency_memory;
+  return Page::kPageSize * spaces_with_emergency_memory;
+}
+
+
 void PagedSpace::CreateEmergencyMemory() {
   if (identity() == CODE_SPACE) {
     // Make the emergency block available to the allocator.
     CodeRange* code_range = heap()->isolate()->code_range();
     if (code_range != NULL && code_range->valid()) {
       code_range->ReleaseEmergencyBlock();
     }
     DCHECK(MemoryAllocator::CodePageAreaSize() == AreaSize());
   }
   emergency_memory_ = heap()->isolate()->memory_allocator()->AllocateChunk(
@@ skipping 1990 matching lines @@
     object->ShortPrint();
     PrintF("\n");
   }
   printf(" --------------------------------------\n");
   printf(" Marked: %x, LiveCount: %x\n", mark_size, LiveBytes());
 }
 
 #endif  // DEBUG
 }
 }  // namespace v8::internal