[cleanup] Remove VirtualMemory::TakeControl

Use the existing move assignment operator instead.

R=ulan@chromium.org

Bug: v8:9183
Change-Id: Id7a4427da2bbf92d2954faba06e24afe64cb9818
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1594729
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#61236}

src/allocation.cc

@@ -283,12 +283,5 @@ void VirtualMemory::Free() {
                   RoundUp(region.size(), page_allocator->AllocatePageSize())));
 }
 
-void VirtualMemory::TakeControl(VirtualMemory* from) {
-  DCHECK(!IsReserved());
-  page_allocator_ = from->page_allocator_;
-  region_ = from->region_;
-  from->Reset();
-}
-
 }  // namespace internal
 }  // namespace v8

src/allocation.h

@@ -186,11 +186,14 @@ class V8_EXPORT_PRIVATE VirtualMemory final {
   ~VirtualMemory();
 
   // Move constructor.
-  VirtualMemory(VirtualMemory&& other) V8_NOEXCEPT { TakeControl(&other); }
+  VirtualMemory(VirtualMemory&& other) V8_NOEXCEPT { *this = std::move(other); }
 
   // Move assignment operator.
   VirtualMemory& operator=(VirtualMemory&& other) V8_NOEXCEPT {
-    TakeControl(&other);
+    DCHECK(!IsReserved());
+    page_allocator_ = other.page_allocator_;
+    region_ = other.region_;
+    other.Reset();
     return *this;
   }
 
@@ -235,10 +238,6 @@ class V8_EXPORT_PRIVATE VirtualMemory final {
   // Frees all memory.
   void Free();
 
-  // Assign control of the reserved region to a different VirtualMemory object.
-  // The old object is no longer functional (IsReserved() returns false).
-  void TakeControl(VirtualMemory* from);
-
   bool InVM(Address address, size_t size) {
     return region_.contains(address, size);
   }

src/heap/spaces.cc

@@ -207,7 +207,7 @@ void MemoryAllocator::InitializeCodePageAllocator(
       NewEvent("CodeRange", reinterpret_cast<void*>(reservation.address()),
                requested));
 
-  heap_reservation_.TakeControl(&reservation);
+  heap_reservation_ = std::move(reservation);
   code_page_allocator_instance_ = base::make_unique<base::BoundedPageAllocator>(
       page_allocator, aligned_base, size,
       static_cast<size_t>(MemoryChunk::kAlignment));
@@ -457,7 +457,7 @@ Address MemoryAllocator::AllocateAlignedMemory(
     return kNullAddress;
   }
 
-  controller->TakeControl(&reservation);
+  *controller = std::move(reservation);
   return base;
 }
 
@@ -942,7 +942,7 @@ MemoryChunk* MemoryAllocator::AllocateChunk(size_t reserve_area_size,
   // linear allocation area.
   if ((base + chunk_size) == 0u) {
     CHECK(!last_chunk_.IsReserved());
-    last_chunk_.TakeControl(&reservation);
+    last_chunk_ = std::move(reservation);
     UncommitMemory(&last_chunk_);
     size_ -= chunk_size;
     if (executable == EXECUTABLE) {

src/heap/store-buffer.cc

@@ -78,7 +78,7 @@ void StoreBuffer::SetUp() {
   }
   current_ = 0;
   top_ = start_[current_];
-  virtual_memory_.TakeControl(&reservation);
+  virtual_memory_ = std::move(reservation);
 }
 
 void StoreBuffer::TearDown() {