diff --git a/test/cctest/heap/test-spaces.cc b/test/cctest/heap/test-spaces.cc
new file mode 100644
index 0000000..2fe099d
--- /dev/null
+++ b/test/cctest/heap/test-spaces.cc
@@ -0,0 +1,929 @@
+// Copyright 2011 the V8 project authors. All rights reserved.
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+//       notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+//       copyright notice, this list of conditions and the following
+//       disclaimer in the documentation and/or other materials provided
+//       with the distribution.
+//     * Neither the name of Google Inc. nor the names of its
+//       contributors may be used to endorse or promote products derived
+//       from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#include <stdlib.h>
+
+#include "src/base/platform/platform.h"
+#include "src/snapshot/snapshot.h"
+#include "src/v8.h"
+#include "test/cctest/cctest.h"
+#include "test/cctest/heap/heap-tester.h"
+#include "test/cctest/heap/utils-inl.h"
+
+namespace v8 {
+namespace internal {
+
+#if 0
+static void VerifyRegionMarking(Address page_start) {
+#ifdef ENABLE_CARDMARKING_WRITE_BARRIER
+  Page* p = Page::FromAddress(page_start);
+
+  p->SetRegionMarks(Page::kAllRegionsCleanMarks);
+
+  for (Address addr = p->ObjectAreaStart();
+       addr < p->ObjectAreaEnd();
+       addr += kPointerSize) {
+    CHECK(!Page::FromAddress(addr)->IsRegionDirty(addr));
+  }
+
+  for (Address addr = p->ObjectAreaStart();
+       addr < p->ObjectAreaEnd();
+       addr += kPointerSize) {
+    Page::FromAddress(addr)->MarkRegionDirty(addr);
+  }
+
+  for (Address addr = p->ObjectAreaStart();
+       addr < p->ObjectAreaEnd();
+       addr += kPointerSize) {
+    CHECK(Page::FromAddress(addr)->IsRegionDirty(addr));
+  }
+#endif
+}
+#endif
+
+
+// TODO(gc) you can no longer allocate pages like this. Details are hidden.
+#if 0
+TEST(Page) {
+  byte* mem = NewArray<byte>(2*Page::kPageSize);
+  CHECK(mem != NULL);
+
+  Address start = reinterpret_cast<Address>(mem);
+  Address page_start = RoundUp(start, Page::kPageSize);
+
+  Page* p = Page::FromAddress(page_start);
+  // Initialized Page has heap pointer, normally set by memory_allocator.
+  p->heap_ = CcTest::heap();
+  CHECK(p->address() == page_start);
+  CHECK(p->is_valid());
+
+  p->opaque_header = 0;
+  p->SetIsLargeObjectPage(false);
+  CHECK(!p->next_page()->is_valid());
+
+  CHECK(p->ObjectAreaStart() == page_start + Page::kObjectStartOffset);
+  CHECK(p->ObjectAreaEnd() == page_start + Page::kPageSize);
+
+  CHECK(p->Offset(page_start + Page::kObjectStartOffset) ==
+        Page::kObjectStartOffset);
+  CHECK(p->Offset(page_start + Page::kPageSize) == Page::kPageSize);
+
+  CHECK(p->OffsetToAddress(Page::kObjectStartOffset) == p->ObjectAreaStart());
+  CHECK(p->OffsetToAddress(Page::kPageSize) == p->ObjectAreaEnd());
+
+  // test region marking
+  VerifyRegionMarking(page_start);
+
+  DeleteArray(mem);
+}
+#endif
+
+
+// Temporarily sets a given allocator in an isolate.
+class TestMemoryAllocatorScope {
+ public:
+  TestMemoryAllocatorScope(Isolate* isolate, MemoryAllocator* allocator)
+      : isolate_(isolate),
+        old_allocator_(isolate->memory_allocator_) {
+    isolate->memory_allocator_ = allocator;
+  }
+
+  ~TestMemoryAllocatorScope() {
+    isolate_->memory_allocator_ = old_allocator_;
+  }
+
+ private:
+  Isolate* isolate_;
+  MemoryAllocator* old_allocator_;
+
+  DISALLOW_COPY_AND_ASSIGN(TestMemoryAllocatorScope);
+};
+
+
+// Temporarily sets a given code range in an isolate.
+class TestCodeRangeScope {
+ public:
+  TestCodeRangeScope(Isolate* isolate, CodeRange* code_range)
+      : isolate_(isolate),
+        old_code_range_(isolate->code_range_) {
+    isolate->code_range_ = code_range;
+  }
+
+  ~TestCodeRangeScope() {
+    isolate_->code_range_ = old_code_range_;
+  }
+
+ private:
+  Isolate* isolate_;
+  CodeRange* old_code_range_;
+
+  DISALLOW_COPY_AND_ASSIGN(TestCodeRangeScope);
+};
+
+
+static void VerifyMemoryChunk(Isolate* isolate,
+                              Heap* heap,
+                              CodeRange* code_range,
+                              size_t reserve_area_size,
+                              size_t commit_area_size,
+                              size_t second_commit_area_size,
+                              Executability executable) {
+  MemoryAllocator* memory_allocator = new MemoryAllocator(isolate);
+  CHECK(memory_allocator->SetUp(heap->MaxReserved(),
+                                heap->MaxExecutableSize()));
+  TestMemoryAllocatorScope test_allocator_scope(isolate, memory_allocator);
+  TestCodeRangeScope test_code_range_scope(isolate, code_range);
+
+  size_t header_size = (executable == EXECUTABLE)
+                       ? MemoryAllocator::CodePageGuardStartOffset()
+                       : MemoryChunk::kObjectStartOffset;
+  size_t guard_size = (executable == EXECUTABLE)
+                       ? MemoryAllocator::CodePageGuardSize()
+                       : 0;
+
+  MemoryChunk* memory_chunk = memory_allocator->AllocateChunk(reserve_area_size,
+                                                              commit_area_size,
+                                                              executable,
+                                                              NULL);
+  size_t alignment = code_range != NULL && code_range->valid()
+                         ? MemoryChunk::kAlignment
+                         : base::OS::CommitPageSize();
+  size_t reserved_size =
+      ((executable == EXECUTABLE))
+          ? RoundUp(header_size + guard_size + reserve_area_size + guard_size,
+                    alignment)
+          : RoundUp(header_size + reserve_area_size,
+                    base::OS::CommitPageSize());
+  CHECK(memory_chunk->size() == reserved_size);
+  CHECK(memory_chunk->area_start() < memory_chunk->address() +
+                                     memory_chunk->size());
+  CHECK(memory_chunk->area_end() <= memory_chunk->address() +
+                                    memory_chunk->size());
+  CHECK(static_cast<size_t>(memory_chunk->area_size()) == commit_area_size);
+
+  Address area_start = memory_chunk->area_start();
+
+  memory_chunk->CommitArea(second_commit_area_size);
+  CHECK(area_start == memory_chunk->area_start());
+  CHECK(memory_chunk->area_start() < memory_chunk->address() +
+                                     memory_chunk->size());
+  CHECK(memory_chunk->area_end() <= memory_chunk->address() +
+                                    memory_chunk->size());
+  CHECK(static_cast<size_t>(memory_chunk->area_size()) ==
+      second_commit_area_size);
+
+  memory_allocator->Free(memory_chunk);
+  memory_allocator->TearDown();
+  delete memory_allocator;
+}
+
+
+TEST(Regress3540) {
+  Isolate* isolate = CcTest::i_isolate();
+  Heap* heap = isolate->heap();
+  const int pageSize = Page::kPageSize;
+  MemoryAllocator* memory_allocator = new MemoryAllocator(isolate);
+  CHECK(
+      memory_allocator->SetUp(heap->MaxReserved(), heap->MaxExecutableSize()));
+  TestMemoryAllocatorScope test_allocator_scope(isolate, memory_allocator);
+  CodeRange* code_range = new CodeRange(isolate);
+  const size_t code_range_size = 4 * pageSize;
+  if (!code_range->SetUp(
+          code_range_size +
+          RoundUp(v8::base::OS::CommitPageSize() * kReservedCodeRangePages,
+                  MemoryChunk::kAlignment) +
+          v8::internal::MemoryAllocator::CodePageAreaSize())) {
+    return;
+  }
+
+  Address address;
+  size_t size;
+  size_t request_size = code_range_size - 2 * pageSize;
+  address = code_range->AllocateRawMemory(
+      request_size, request_size - (2 * MemoryAllocator::CodePageGuardSize()),
+      &size);
+  CHECK(address != NULL);
+
+  Address null_address;
+  size_t null_size;
+  request_size = code_range_size - pageSize;
+  null_address = code_range->AllocateRawMemory(
+      request_size, request_size - (2 * MemoryAllocator::CodePageGuardSize()),
+      &null_size);
+  CHECK(null_address == NULL);
+
+  code_range->FreeRawMemory(address, size);
+  delete code_range;
+  memory_allocator->TearDown();
+  delete memory_allocator;
+}
+
+
+static unsigned int Pseudorandom() {
+  static uint32_t lo = 2345;
+  lo = 18273 * (lo & 0xFFFFF) + (lo >> 16);
+  return lo & 0xFFFFF;
+}
+
+
+TEST(MemoryChunk) {
+  Isolate* isolate = CcTest::i_isolate();
+  Heap* heap = isolate->heap();
+
+  size_t reserve_area_size = 1 * MB;
+  size_t initial_commit_area_size, second_commit_area_size;
+
+  for (int i = 0; i < 100; i++) {
+    initial_commit_area_size = Pseudorandom();
+    second_commit_area_size = Pseudorandom();
+
+    // With CodeRange.
+    CodeRange* code_range = new CodeRange(isolate);
+    const size_t code_range_size = 32 * MB;
+    if (!code_range->SetUp(code_range_size)) return;
+
+    VerifyMemoryChunk(isolate,
+                      heap,
+                      code_range,
+                      reserve_area_size,
+                      initial_commit_area_size,
+                      second_commit_area_size,
+                      EXECUTABLE);
+
+    VerifyMemoryChunk(isolate,
+                      heap,
+                      code_range,
+                      reserve_area_size,
+                      initial_commit_area_size,
+                      second_commit_area_size,
+                      NOT_EXECUTABLE);
+    delete code_range;
+
+    // Without CodeRange.
+    code_range = NULL;
+    VerifyMemoryChunk(isolate,
+                      heap,
+                      code_range,
+                      reserve_area_size,
+                      initial_commit_area_size,
+                      second_commit_area_size,
+                      EXECUTABLE);
+
+    VerifyMemoryChunk(isolate,
+                      heap,
+                      code_range,
+                      reserve_area_size,
+                      initial_commit_area_size,
+                      second_commit_area_size,
+                      NOT_EXECUTABLE);
+  }
+}
+
+
+TEST(MemoryAllocator) {
+  Isolate* isolate = CcTest::i_isolate();
+  Heap* heap = isolate->heap();
+
+  MemoryAllocator* memory_allocator = new MemoryAllocator(isolate);
+  CHECK(memory_allocator != nullptr);
+  CHECK(memory_allocator->SetUp(heap->MaxReserved(),
+                                heap->MaxExecutableSize()));
+  TestMemoryAllocatorScope test_scope(isolate, memory_allocator);
+
+  {
+    int total_pages = 0;
+    OldSpace faked_space(heap, OLD_SPACE, NOT_EXECUTABLE);
+    Page* first_page = memory_allocator->AllocatePage(
+        faked_space.AreaSize(), &faked_space, NOT_EXECUTABLE);
+
+    first_page->InsertAfter(faked_space.anchor()->prev_page());
+    CHECK(first_page->is_valid());
+    CHECK(first_page->next_page() == faked_space.anchor());
+    total_pages++;
+
+    for (Page* p = first_page; p != faked_space.anchor(); p = p->next_page()) {
+      CHECK(p->owner() == &faked_space);
+    }
+
+    // Again, we should get n or n - 1 pages.
+    Page* other = memory_allocator->AllocatePage(faked_space.AreaSize(),
+                                                 &faked_space, NOT_EXECUTABLE);
+    CHECK(other->is_valid());
+    total_pages++;
+    other->InsertAfter(first_page);
+    int page_count = 0;
+    for (Page* p = first_page; p != faked_space.anchor(); p = p->next_page()) {
+      CHECK(p->owner() == &faked_space);
+      page_count++;
+    }
+    CHECK(total_pages == page_count);
+
+    Page* second_page = first_page->next_page();
+    CHECK(second_page->is_valid());
+
+    // OldSpace's destructor will tear down the space and free up all pages.
+  }
+  memory_allocator->TearDown();
+  delete memory_allocator;
+}
+
+
+TEST(NewSpace) {
+  Isolate* isolate = CcTest::i_isolate();
+  Heap* heap = isolate->heap();
+  MemoryAllocator* memory_allocator = new MemoryAllocator(isolate);
+  CHECK(memory_allocator->SetUp(heap->MaxReserved(),
+                                heap->MaxExecutableSize()));
+  TestMemoryAllocatorScope test_scope(isolate, memory_allocator);
+
+  NewSpace new_space(heap);
+
+  CHECK(new_space.SetUp(CcTest::heap()->ReservedSemiSpaceSize(),
+                        CcTest::heap()->ReservedSemiSpaceSize()));
+  CHECK(new_space.HasBeenSetUp());
+
+  while (new_space.Available() >= Page::kMaxRegularHeapObjectSize) {
+    Object* obj =
+        new_space.AllocateRawUnaligned(Page::kMaxRegularHeapObjectSize)
+            .ToObjectChecked();
+    CHECK(new_space.Contains(HeapObject::cast(obj)));
+  }
+
+  new_space.TearDown();
+  memory_allocator->TearDown();
+  delete memory_allocator;
+}
+
+
+TEST(OldSpace) {
+  Isolate* isolate = CcTest::i_isolate();
+  Heap* heap = isolate->heap();
+  MemoryAllocator* memory_allocator = new MemoryAllocator(isolate);
+  CHECK(memory_allocator->SetUp(heap->MaxReserved(),
+                                heap->MaxExecutableSize()));
+  TestMemoryAllocatorScope test_scope(isolate, memory_allocator);
+
+  OldSpace* s = new OldSpace(heap, OLD_SPACE, NOT_EXECUTABLE);
+  CHECK(s != NULL);
+
+  CHECK(s->SetUp());
+
+  while (s->Available() > 0) {
+    s->AllocateRawUnaligned(Page::kMaxRegularHeapObjectSize).ToObjectChecked();
+  }
+
+  delete s;
+  memory_allocator->TearDown();
+  delete memory_allocator;
+}
+
+
+TEST(CompactionSpace) {
+  Isolate* isolate = CcTest::i_isolate();
+  Heap* heap = isolate->heap();
+  MemoryAllocator* memory_allocator = new MemoryAllocator(isolate);
+  CHECK(memory_allocator != nullptr);
+  CHECK(
+      memory_allocator->SetUp(heap->MaxReserved(), heap->MaxExecutableSize()));
+  TestMemoryAllocatorScope test_scope(isolate, memory_allocator);
+
+  CompactionSpace* compaction_space =
+      new CompactionSpace(heap, OLD_SPACE, NOT_EXECUTABLE);
+  CHECK(compaction_space != NULL);
+  CHECK(compaction_space->SetUp());
+
+  OldSpace* old_space = new OldSpace(heap, OLD_SPACE, NOT_EXECUTABLE);
+  CHECK(old_space != NULL);
+  CHECK(old_space->SetUp());
+
+  // Cannot loop until "Available()" since we initially have 0 bytes available
+  // and would thus neither grow, nor be able to allocate an object.
+  const int kNumObjects = 100;
+  const int kNumObjectsPerPage =
+      compaction_space->AreaSize() / Page::kMaxRegularHeapObjectSize;
+  const int kExpectedPages =
+      (kNumObjects + kNumObjectsPerPage - 1) / kNumObjectsPerPage;
+  for (int i = 0; i < kNumObjects; i++) {
+    compaction_space->AllocateRawUnaligned(Page::kMaxRegularHeapObjectSize)
+        .ToObjectChecked();
+  }
+  int pages_in_old_space = old_space->CountTotalPages();
+  int pages_in_compaction_space = compaction_space->CountTotalPages();
+  CHECK_EQ(pages_in_compaction_space, kExpectedPages);
+  CHECK_LE(pages_in_old_space, 1);
+
+  old_space->MergeCompactionSpace(compaction_space);
+  CHECK_EQ(old_space->CountTotalPages(),
+           pages_in_old_space + pages_in_compaction_space);
+
+  delete compaction_space;
+  delete old_space;
+
+  memory_allocator->TearDown();
+  delete memory_allocator;
+}
+
+
+TEST(CompactionSpaceUsingExternalMemory) {
+  const int kObjectSize = 512;
+
+  Isolate* isolate = CcTest::i_isolate();
+  Heap* heap = isolate->heap();
+  MemoryAllocator* allocator = new MemoryAllocator(isolate);
+  CHECK(allocator != nullptr);
+  CHECK(allocator->SetUp(heap->MaxReserved(), heap->MaxExecutableSize()));
+  TestMemoryAllocatorScope test_scope(isolate, allocator);
+
+  CompactionSpaceCollection* collection = new CompactionSpaceCollection(heap);
+  CompactionSpace* compaction_space = collection->Get(OLD_SPACE);
+  CHECK(compaction_space != NULL);
+  CHECK(compaction_space->SetUp());
+
+  OldSpace* old_space = new OldSpace(heap, OLD_SPACE, NOT_EXECUTABLE);
+  CHECK(old_space != NULL);
+  CHECK(old_space->SetUp());
+
+  // The linear allocation area already counts as used bytes, making
+  // exact testing impossible.
+  heap->DisableInlineAllocation();
+
+  // Test:
+  // * Allocate a backing store in old_space.
+  // * Compute the number num_rest_objects of kObjectSize objects that fit into
+  //   of available memory.
+  //   kNumRestObjects.
+  // * Add the rest of available memory to the compaction space.
+  // * Allocate kNumRestObjects in the compaction space.
+  // * Allocate one object more.
+  // * Merge the compaction space and compare the expected number of pages.
+
+  // Allocate a single object in old_space to initialize a backing page.
+  old_space->AllocateRawUnaligned(kObjectSize).ToObjectChecked();
+  // Compute the number of objects that fit into the rest in old_space.
+  intptr_t rest = static_cast<int>(old_space->Available());
+  CHECK_GT(rest, 0);
+  intptr_t num_rest_objects = rest / kObjectSize;
+  // After allocating num_rest_objects in compaction_space we allocate a bit
+  // more.
+  const intptr_t kAdditionalCompactionMemory = kObjectSize;
+  // We expect a single old_space page.
+  const intptr_t kExpectedInitialOldSpacePages = 1;
+  // We expect a single additional page in compaction space because we mostly
+  // use external memory.
+  const intptr_t kExpectedCompactionPages = 1;
+  // We expect two pages to be reachable from old_space in the end.
+  const intptr_t kExpectedOldSpacePagesAfterMerge = 2;
+
+  CHECK_EQ(old_space->CountTotalPages(), kExpectedInitialOldSpacePages);
+  CHECK_EQ(compaction_space->CountTotalPages(), 0);
+  CHECK_EQ(compaction_space->Capacity(), 0);
+  // Make the rest of memory available for compaction.
+  old_space->DivideUponCompactionSpaces(&collection, 1, rest);
+  CHECK_EQ(compaction_space->CountTotalPages(), 0);
+  CHECK_EQ(compaction_space->Capacity(), rest);
+  while (num_rest_objects-- > 0) {
+    compaction_space->AllocateRawUnaligned(kObjectSize).ToObjectChecked();
+  }
+  // We only used external memory so far.
+  CHECK_EQ(compaction_space->CountTotalPages(), 0);
+  // Additional allocation.
+  compaction_space->AllocateRawUnaligned(kAdditionalCompactionMemory)
+      .ToObjectChecked();
+  // Now the compaction space shouldve also acquired a page.
+  CHECK_EQ(compaction_space->CountTotalPages(), kExpectedCompactionPages);
+
+  old_space->MergeCompactionSpace(compaction_space);
+  CHECK_EQ(old_space->CountTotalPages(), kExpectedOldSpacePagesAfterMerge);
+
+  delete collection;
+  delete old_space;
+
+  allocator->TearDown();
+  delete allocator;
+}
+
+
+CompactionSpaceCollection** HeapTester::InitializeCompactionSpaces(
+    Heap* heap, int num_spaces) {
+  CompactionSpaceCollection** spaces =
+      new CompactionSpaceCollection*[num_spaces];
+  for (int i = 0; i < num_spaces; i++) {
+    spaces[i] = new CompactionSpaceCollection(heap);
+  }
+  return spaces;
+}
+
+
+void HeapTester::DestroyCompactionSpaces(CompactionSpaceCollection** spaces,
+                                         int num_spaces) {
+  for (int i = 0; i < num_spaces; i++) {
+    delete spaces[i];
+  }
+  delete[] spaces;
+}
+
+
+void HeapTester::MergeCompactionSpaces(PagedSpace* space,
+                                       CompactionSpaceCollection** spaces,
+                                       int num_spaces) {
+  AllocationSpace id = space->identity();
+  for (int i = 0; i < num_spaces; i++) {
+    space->MergeCompactionSpace(spaces[i]->Get(id));
+    CHECK_EQ(spaces[i]->Get(id)->accounting_stats_.Size(), 0);
+    CHECK_EQ(spaces[i]->Get(id)->accounting_stats_.Capacity(), 0);
+    CHECK_EQ(spaces[i]->Get(id)->Waste(), 0);
+  }
+}
+
+
+void HeapTester::AllocateInCompactionSpaces(CompactionSpaceCollection** spaces,
+                                            AllocationSpace id, int num_spaces,
+                                            int num_objects, int object_size) {
+  for (int i = 0; i < num_spaces; i++) {
+    for (int j = 0; j < num_objects; j++) {
+      spaces[i]->Get(id)->AllocateRawUnaligned(object_size).ToObjectChecked();
+    }
+    spaces[i]->Get(id)->EmptyAllocationInfo();
+    CHECK_EQ(spaces[i]->Get(id)->accounting_stats_.Size(),
+             num_objects * object_size);
+    CHECK_GE(spaces[i]->Get(id)->accounting_stats_.Capacity(),
+             spaces[i]->Get(id)->accounting_stats_.Size());
+  }
+}
+
+
+void HeapTester::CompactionStats(CompactionSpaceCollection** spaces,
+                                 AllocationSpace id, int num_spaces,
+                                 intptr_t* capacity, intptr_t* size) {
+  *capacity = 0;
+  *size = 0;
+  for (int i = 0; i < num_spaces; i++) {
+    *capacity += spaces[i]->Get(id)->accounting_stats_.Capacity();
+    *size += spaces[i]->Get(id)->accounting_stats_.Size();
+  }
+}
+
+
+void HeapTester::TestCompactionSpaceDivide(int num_additional_objects,
+                                           int object_size,
+                                           int num_compaction_spaces,
+                                           int additional_capacity_in_bytes) {
+  Isolate* isolate = CcTest::i_isolate();
+  Heap* heap = isolate->heap();
+  OldSpace* old_space = new OldSpace(heap, OLD_SPACE, NOT_EXECUTABLE);
+  CHECK(old_space != nullptr);
+  CHECK(old_space->SetUp());
+  old_space->AllocateRawUnaligned(object_size).ToObjectChecked();
+  old_space->EmptyAllocationInfo();
+
+  intptr_t rest_capacity = old_space->accounting_stats_.Capacity() -
+                           old_space->accounting_stats_.Size();
+  intptr_t capacity_for_compaction_space =
+      rest_capacity / num_compaction_spaces;
+  int num_objects_in_compaction_space =
+      static_cast<int>(capacity_for_compaction_space) / object_size +
+      num_additional_objects;
+  CHECK_GT(num_objects_in_compaction_space, 0);
+  intptr_t initial_old_space_capacity = old_space->accounting_stats_.Capacity();
+
+  CompactionSpaceCollection** spaces =
+      InitializeCompactionSpaces(heap, num_compaction_spaces);
+  old_space->DivideUponCompactionSpaces(spaces, num_compaction_spaces,
+                                        capacity_for_compaction_space);
+
+  intptr_t compaction_capacity = 0;
+  intptr_t compaction_size = 0;
+  CompactionStats(spaces, OLD_SPACE, num_compaction_spaces,
+                  &compaction_capacity, &compaction_size);
+
+  intptr_t old_space_capacity = old_space->accounting_stats_.Capacity();
+  intptr_t old_space_size = old_space->accounting_stats_.Size();
+  // Compaction space memory is subtracted from the original space's capacity.
+  CHECK_EQ(old_space_capacity,
+           initial_old_space_capacity - compaction_capacity);
+  CHECK_EQ(compaction_size, 0);
+
+  AllocateInCompactionSpaces(spaces, OLD_SPACE, num_compaction_spaces,
+                             num_objects_in_compaction_space, object_size);
+
+  // Old space size and capacity should be the same as after dividing.
+  CHECK_EQ(old_space->accounting_stats_.Size(), old_space_size);
+  CHECK_EQ(old_space->accounting_stats_.Capacity(), old_space_capacity);
+
+  CompactionStats(spaces, OLD_SPACE, num_compaction_spaces,
+                  &compaction_capacity, &compaction_size);
+  MergeCompactionSpaces(old_space, spaces, num_compaction_spaces);
+
+  CHECK_EQ(old_space->accounting_stats_.Capacity(),
+           old_space_capacity + compaction_capacity);
+  CHECK_EQ(old_space->accounting_stats_.Size(),
+           old_space_size + compaction_size);
+  // We check against the expected end capacity.
+  CHECK_EQ(old_space->accounting_stats_.Capacity(),
+           initial_old_space_capacity + additional_capacity_in_bytes);
+
+  DestroyCompactionSpaces(spaces, num_compaction_spaces);
+  delete old_space;
+}
+
+
+HEAP_TEST(CompactionSpaceDivideSinglePage) {
+  const int kObjectSize = KB;
+  const int kCompactionSpaces = 4;
+  // Since the bound for objects is tight and the dividing is best effort, we
+  // subtract some objects to make sure we still fit in the initial page.
+  // A CHECK makes sure that the overall number of allocated objects stays
+  // > 0.
+  const int kAdditionalObjects = -10;
+  const int kAdditionalCapacityRequired = 0;
+  TestCompactionSpaceDivide(kAdditionalObjects, kObjectSize, kCompactionSpaces,
+                            kAdditionalCapacityRequired);
+}
+
+
+HEAP_TEST(CompactionSpaceDivideMultiplePages) {
+  const int kObjectSize = KB;
+  const int kCompactionSpaces = 4;
+  // Allocate half a page of objects to ensure that we need one more page per
+  // compaction space.
+  const int kAdditionalObjects = (Page::kPageSize / kObjectSize / 2);
+  const int kAdditionalCapacityRequired =
+      Page::kAllocatableMemory * kCompactionSpaces;
+  TestCompactionSpaceDivide(kAdditionalObjects, kObjectSize, kCompactionSpaces,
+                            kAdditionalCapacityRequired);
+}
+
+
+TEST(LargeObjectSpace) {
+  v8::V8::Initialize();
+
+  LargeObjectSpace* lo = CcTest::heap()->lo_space();
+  CHECK(lo != NULL);
+
+  int lo_size = Page::kPageSize;
+
+  Object* obj = lo->AllocateRaw(lo_size, NOT_EXECUTABLE).ToObjectChecked();
+  CHECK(obj->IsHeapObject());
+
+  HeapObject* ho = HeapObject::cast(obj);
+
+  CHECK(lo->Contains(HeapObject::cast(obj)));
+
+  CHECK(lo->FindObject(ho->address()) == obj);
+
+  CHECK(lo->Contains(ho));
+
+  while (true) {
+    intptr_t available = lo->Available();
+    { AllocationResult allocation = lo->AllocateRaw(lo_size, NOT_EXECUTABLE);
+      if (allocation.IsRetry()) break;
+    }
+    // The available value is conservative such that it may report
+    // zero prior to heap exhaustion.
+    CHECK(lo->Available() < available || available == 0);
+  }
+
+  CHECK(!lo->IsEmpty());
+
+  CHECK(lo->AllocateRaw(lo_size, NOT_EXECUTABLE).IsRetry());
+}
+
+
+TEST(SizeOfFirstPageIsLargeEnough) {
+  if (i::FLAG_always_opt) return;
+  // Bootstrapping without a snapshot causes more allocations.
+  CcTest::InitializeVM();
+  Isolate* isolate = CcTest::i_isolate();
+  if (!isolate->snapshot_available()) return;
+  if (Snapshot::EmbedsScript(isolate)) return;
+
+  // If this test fails due to enabling experimental natives that are not part
+  // of the snapshot, we may need to adjust CalculateFirstPageSizes.
+
+  // Freshly initialized VM gets by with one page per space.
+  for (int i = FIRST_PAGED_SPACE; i <= LAST_PAGED_SPACE; i++) {
+    // Debug code can be very large, so skip CODE_SPACE if we are generating it.
+    if (i == CODE_SPACE && i::FLAG_debug_code) continue;
+    CHECK_EQ(1, isolate->heap()->paged_space(i)->CountTotalPages());
+  }
+
+  // Executing the empty script gets by with one page per space.
+  HandleScope scope(isolate);
+  CompileRun("/*empty*/");
+  for (int i = FIRST_PAGED_SPACE; i <= LAST_PAGED_SPACE; i++) {
+    // Debug code can be very large, so skip CODE_SPACE if we are generating it.
+    if (i == CODE_SPACE && i::FLAG_debug_code) continue;
+    CHECK_EQ(1, isolate->heap()->paged_space(i)->CountTotalPages());
+  }
+
+  // No large objects required to perform the above steps.
+  CHECK(isolate->heap()->lo_space()->IsEmpty());
+}
+
+
+UNINITIALIZED_TEST(NewSpaceGrowsToTargetCapacity) {
+  FLAG_target_semi_space_size = 2 * (Page::kPageSize / MB);
+  if (FLAG_optimize_for_size) return;
+
+  v8::Isolate::CreateParams create_params;
+  create_params.array_buffer_allocator = CcTest::array_buffer_allocator();
+  v8::Isolate* isolate = v8::Isolate::New(create_params);
+  {
+    v8::Isolate::Scope isolate_scope(isolate);
+    v8::HandleScope handle_scope(isolate);
+    v8::Context::New(isolate)->Enter();
+
+    Isolate* i_isolate = reinterpret_cast<Isolate*>(isolate);
+
+    NewSpace* new_space = i_isolate->heap()->new_space();
+
+    // This test doesn't work if we start with a non-default new space
+    // configuration.
+    if (new_space->InitialTotalCapacity() == Page::kPageSize) {
+      CHECK_EQ(new_space->CommittedMemory(), new_space->InitialTotalCapacity());
+
+      // Fill up the first (and only) page of the semi space.
+      FillCurrentPage(new_space);
+
+      // Try to allocate out of the new space. A new page should be added and
+      // the
+      // allocation should succeed.
+      v8::internal::AllocationResult allocation =
+          new_space->AllocateRawUnaligned(80);
+      CHECK(!allocation.IsRetry());
+      CHECK_EQ(new_space->CommittedMemory(), 2 * Page::kPageSize);
+
+      // Turn the allocation into a proper object so isolate teardown won't
+      // crash.
+      HeapObject* free_space = NULL;
+      CHECK(allocation.To(&free_space));
+      new_space->heap()->CreateFillerObjectAt(free_space->address(), 80);
+    }
+  }
+  isolate->Dispose();
+}
+
+
+static HeapObject* AllocateUnaligned(NewSpace* space, int size) {
+  AllocationResult allocation = space->AllocateRawUnaligned(size);
+  CHECK(!allocation.IsRetry());
+  HeapObject* filler = NULL;
+  CHECK(allocation.To(&filler));
+  space->heap()->CreateFillerObjectAt(filler->address(), size);
+  return filler;
+}
+
+class Observer : public InlineAllocationObserver {
+ public:
+  explicit Observer(intptr_t step_size)
+      : InlineAllocationObserver(step_size), count_(0) {}
+
+  void Step(int bytes_allocated, Address, size_t) override { count_++; }
+
+  int count() const { return count_; }
+
+ private:
+  int count_;
+};
+
+
+UNINITIALIZED_TEST(InlineAllocationObserver) {
+  v8::Isolate::CreateParams create_params;
+  create_params.array_buffer_allocator = CcTest::array_buffer_allocator();
+  v8::Isolate* isolate = v8::Isolate::New(create_params);
+  {
+    v8::Isolate::Scope isolate_scope(isolate);
+    v8::HandleScope handle_scope(isolate);
+    v8::Context::New(isolate)->Enter();
+
+    Isolate* i_isolate = reinterpret_cast<Isolate*>(isolate);
+
+    NewSpace* new_space = i_isolate->heap()->new_space();
+
+    Observer observer1(128);
+    new_space->AddInlineAllocationObserver(&observer1);
+
+    // The observer should not get notified if we have only allocated less than
+    // 128 bytes.
+    AllocateUnaligned(new_space, 64);
+    CHECK_EQ(observer1.count(), 0);
+
+    // The observer should get called when we have allocated exactly 128 bytes.
+    AllocateUnaligned(new_space, 64);
+    CHECK_EQ(observer1.count(), 1);
+
+    // Another >128 bytes should get another notification.
+    AllocateUnaligned(new_space, 136);
+    CHECK_EQ(observer1.count(), 2);
+
+    // Allocating a large object should get only one notification.
+    AllocateUnaligned(new_space, 1024);
+    CHECK_EQ(observer1.count(), 3);
+
+    // Allocating another 2048 bytes in small objects should get 16
+    // notifications.
+    for (int i = 0; i < 64; ++i) {
+      AllocateUnaligned(new_space, 32);
+    }
+    CHECK_EQ(observer1.count(), 19);
+
+    // Multiple observers should work.
+    Observer observer2(96);
+    new_space->AddInlineAllocationObserver(&observer2);
+
+    AllocateUnaligned(new_space, 2048);
+    CHECK_EQ(observer1.count(), 20);
+    CHECK_EQ(observer2.count(), 1);
+
+    AllocateUnaligned(new_space, 104);
+    CHECK_EQ(observer1.count(), 20);
+    CHECK_EQ(observer2.count(), 2);
+
+    // Callback should stop getting called after an observer is removed.
+    new_space->RemoveInlineAllocationObserver(&observer1);
+
+    AllocateUnaligned(new_space, 384);
+    CHECK_EQ(observer1.count(), 20);  // no more notifications.
+    CHECK_EQ(observer2.count(), 3);   // this one is still active.
+
+    // Ensure that PauseInlineAllocationObserversScope work correctly.
+    AllocateUnaligned(new_space, 48);
+    CHECK_EQ(observer2.count(), 3);
+    {
+      PauseInlineAllocationObserversScope pause_observers(new_space);
+      CHECK_EQ(observer2.count(), 3);
+      AllocateUnaligned(new_space, 384);
+      CHECK_EQ(observer2.count(), 3);
+    }
+    CHECK_EQ(observer2.count(), 3);
+    // Coupled with the 48 bytes allocated before the pause, another 48 bytes
+    // allocated here should trigger a notification.
+    AllocateUnaligned(new_space, 48);
+    CHECK_EQ(observer2.count(), 4);
+
+    new_space->RemoveInlineAllocationObserver(&observer2);
+    AllocateUnaligned(new_space, 384);
+    CHECK_EQ(observer1.count(), 20);
+    CHECK_EQ(observer2.count(), 4);
+  }
+  isolate->Dispose();
+}
+
+
+UNINITIALIZED_TEST(InlineAllocationObserverCadence) {
+  v8::Isolate::CreateParams create_params;
+  create_params.array_buffer_allocator = CcTest::array_buffer_allocator();
+  v8::Isolate* isolate = v8::Isolate::New(create_params);
+  {
+    v8::Isolate::Scope isolate_scope(isolate);
+    v8::HandleScope handle_scope(isolate);
+    v8::Context::New(isolate)->Enter();
+
+    Isolate* i_isolate = reinterpret_cast<Isolate*>(isolate);
+
+    NewSpace* new_space = i_isolate->heap()->new_space();
+
+    Observer observer1(512);
+    new_space->AddInlineAllocationObserver(&observer1);
+    Observer observer2(576);
+    new_space->AddInlineAllocationObserver(&observer2);
+
+    for (int i = 0; i < 512; ++i) {
+      AllocateUnaligned(new_space, 32);
+    }
+
+    new_space->RemoveInlineAllocationObserver(&observer1);
+    new_space->RemoveInlineAllocationObserver(&observer2);
+
+    CHECK_EQ(observer1.count(), 32);
+    CHECK_EQ(observer2.count(), 28);
+  }
+  isolate->Dispose();
+}
+
+}  // namespace internal
+}  // namespace v8