Revert of [handles] Sanitize Handle and friends.

src/handles.cc

 // Copyright 2012 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/handles.h"
 
-#include "src/api.h"
-#include "src/isolate.h"
-
 namespace v8 {
 namespace internal {
 
-HandleBase::HandleBase(HeapObject* object)
-    : HandleBase(object, object->GetIsolate()) {}
 
-
-HandleBase::HandleBase(Object* object, Isolate* isolate)
-    : HandleBase(HandleScope::CreateHandle(isolate, object)) {}
-
-
-#ifdef DEBUG
-
-bool HandleBase::IsDereferenceAllowed(DereferenceCheckMode mode) const {
-  DCHECK_NOT_NULL(location_);
-  Object* const object = *location_;
-  if (object->IsSmi()) return true;
-  HeapObject* const heap_object = HeapObject::cast(object);
-  Heap* const heap = heap_object->GetHeap();
-  Object** roots_array_start = heap->roots_array_start();
-  if (roots_array_start <= location_ &&
-      location_ < roots_array_start + Heap::kStrongRootListLength &&
-      heap->RootCanBeTreatedAsConstant(
-          static_cast<Heap::RootListIndex>(location_ - roots_array_start))) {
-    return true;
-  }
-  if (!AllowHandleDereference::IsAllowed()) return false;
-  if (mode == INCLUDE_DEFERRED_CHECK &&
-      !AllowDeferredHandleDereference::IsAllowed()) {
-    // Accessing cells, maps and internalized strings is safe.
-    if (heap_object->IsCell()) return true;
-    if (heap_object->IsMap()) return true;
-    if (heap_object->IsInternalizedString()) return true;
-    return !heap->isolate()->IsDeferredHandle(location_);
-  }
-  return true;
-}
-
-#endif  // DEBUG
-
-
-HandleScope::HandleScope(Isolate* isolate) : isolate_(isolate) {
-  HandleScopeData* const current = isolate->handle_scope_data();
-  prev_next_ = current->next;
-  prev_limit_ = current->limit;
-  current->level++;
-}
-
-
-HandleScope::~HandleScope() { CloseScope(isolate_, prev_next_, prev_limit_); }
-
-
-// static
 int HandleScope::NumberOfHandles(Isolate* isolate) {
   HandleScopeImplementer* impl = isolate->handle_scope_implementer();
   int n = impl->blocks()->length();
   if (n == 0) return 0;
   return ((n - 1) * kHandleBlockSize) + static_cast<int>(
       (isolate->handle_scope_data()->next - impl->blocks()->last()));
 }
 
 
-// static
-Object** HandleScope::CreateHandle(Isolate* isolate, Object* value) {
-  DCHECK(AllowHandleAllocation::IsAllowed());
-  HandleScopeData* const current = isolate->handle_scope_data();
-
-  Object** result = current->next;
-  if (result == current->limit) result = Extend(isolate);
-  // Update the current next field, set the value in the created
-  // handle, and return the result.
-  DCHECK_LT(result, current->limit);
-  current->next = result + 1;
-
-  *result = value;
-  return result;
-}
-
-
-// static
-void HandleScope::DeleteExtensions(Isolate* isolate) {
-  HandleScopeData* const current = isolate->handle_scope_data();
-  isolate->handle_scope_implementer()->DeleteExtensions(current->limit);
-}
-
-
-Handle<Object> HandleScope::CloseAndEscape(Handle<Object> handle) {
-  HandleScopeData* const current = isolate_->handle_scope_data();
-
-  Object* value = *handle;
-  // Throw away all handles in the current scope.
-  CloseScope(isolate_, prev_next_, prev_limit_);
-  // Allocate one handle in the parent scope.
-  DCHECK_LT(0, current->level);
-  Handle<Object> result(CreateHandle(isolate_, value));
-  // Reinitialize the current scope (so that it's ready
-  // to be used or closed again).
-  prev_next_ = current->next;
-  prev_limit_ = current->limit;
-  current->level++;
-  return result;
-}
-
-
-// static
-void HandleScope::CloseScope(Isolate* isolate, Object** prev_next,
-                             Object** prev_limit) {
-  HandleScopeData* const current = isolate->handle_scope_data();
-
-  std::swap(current->next, prev_next);
-  current->level--;
-  if (current->limit != prev_limit) {
-    current->limit = prev_limit;
-    DeleteExtensions(isolate);
-#ifdef ENABLE_HANDLE_ZAPPING
-    ZapRange(current->next, prev_limit);
-  } else {
-    ZapRange(current->next, prev_next);
-#endif
-  }
-}
-
-
-// static
 Object** HandleScope::Extend(Isolate* isolate) {
   HandleScopeData* current = isolate->handle_scope_data();
 
   Object** result = current->next;
-  DCHECK_EQ(result, current->limit);
+
+  DCHECK(result == current->limit);
   // Make sure there's at least one scope on the stack and that the
   // top of the scope stack isn't a barrier.
   if (!Utils::ApiCheck(current->level != 0,
                        "v8::HandleScope::CreateHandle()",
                        "Cannot create a handle without a HandleScope")) {
     return NULL;
   }
   HandleScopeImplementer* impl = isolate->handle_scope_implementer();
   // If there's more room in the last block, we use that. This is used
   // for fast creation of scopes after scope barriers.
@@ skipping 13 matching lines @@
     // Add the extension to the global list of blocks, but count the
     // extension as part of the current scope.
     impl->blocks()->Add(result);
     current->limit = &result[kHandleBlockSize];
   }
 
   return result;
 }
 
 
+void HandleScope::DeleteExtensions(Isolate* isolate) {
+  HandleScopeData* current = isolate->handle_scope_data();
+  isolate->handle_scope_implementer()->DeleteExtensions(current->limit);
+}
+
+
 #ifdef ENABLE_HANDLE_ZAPPING
 void HandleScope::ZapRange(Object** start, Object** end) {
   DCHECK(end - start <= kHandleBlockSize);
   for (Object** p = start; p != end; p++) {
     *reinterpret_cast<Address*>(p) = v8::internal::kHandleZapValue;
   }
 }
 #endif
 
 
@@ skipping 43 matching lines @@
   DeferredHandles* deferred = impl_->Detach(prev_limit_);
   HandleScopeData* data = impl_->isolate()->handle_scope_data();
   data->next = prev_next_;
   data->limit = prev_limit_;
 #ifdef DEBUG
   handles_detached_ = true;
 #endif
   return deferred;
 }
 
-
-#ifdef DEBUG
-
-SealHandleScope::SealHandleScope(Isolate* isolate) : isolate_(isolate) {
-  // Make sure the current thread is allowed to create handles to begin with.
-  CHECK(AllowHandleAllocation::IsAllowed());
-  HandleScopeData* const current = isolate_->handle_scope_data();
-  // Shrink the current handle scope to make it impossible to do
-  // handle allocations without an explicit handle scope.
-  limit_ = current->limit;
-  current->limit = current->next;
-  level_ = current->level;
-  current->level = 0;
-}
-
-
-SealHandleScope::~SealHandleScope() {
-  // Restore state in current handle scope to re-enable handle
-  // allocations.
-  HandleScopeData* const current = isolate_->handle_scope_data();
-  DCHECK_EQ(0, current->level);
-  current->level = level_;
-  DCHECK_EQ(current->next, current->limit);
-  current->limit = limit_;
-}
-
-#endif  // DEBUG
-
-}  // namespace internal
-}  // namespace v8
+} }  // namespace v8::internal