allocation-site-scopes.h

Go to the documentation of this file.

// Copyright 2013 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.
 
#ifndef V8_OBJECTS_ALLOCATION_SITE_SCOPES_H_
#define V8_OBJECTS_ALLOCATION_SITE_SCOPES_H_
 
#include "src/handles/handles.h"
#include "src/objects/allocation-site.h"
#include "src/objects/map.h"
#include "src/objects/objects.h"
 
namespace v8 {
namespace internal {
 
// AllocationSiteContext is the base class for walking and copying a nested
// boilerplate with AllocationSite and AllocationMemento support.
class AllocationSiteContext {
 public:
  explicit AllocationSiteContext(Isolate* isolate) { isolate_ = isolate; }
 
  DirectHandle<AllocationSite> top() { return top_; }
  DirectHandle<AllocationSite> current() { return current_; }
 
  bool ShouldCreateMemento(DirectHandle<JSObject> object) { return false; }
 
  Isolate* isolate() { return isolate_; }
 
 protected:
  void update_current_site(Tagged<AllocationSite> site) {
    current_.PatchValue(site);
  }
 
  inline void InitializeTraversal(Handle<AllocationSite> site);
 
 private:
  Isolate* isolate_;
  Handle<AllocationSite> top_;
  Handle<AllocationSite> current_;
};
 
// AllocationSiteUsageContext aids in the creation of AllocationMementos placed
// behind some/all components of a copied object literal.
class AllocationSiteUsageContext : public AllocationSiteContext {
 public:
  AllocationSiteUsageContext(Isolate* isolate, Handle<AllocationSite> site,
                             bool activated)
      : AllocationSiteContext(isolate),
        top_site_(site),
        activated_(activated) {}
 
  inline Handle<AllocationSite> EnterNewScope();
 
  inline void ExitScope(DirectHandle<AllocationSite> scope_site,
                        DirectHandle<JSObject> object);
 
  inline bool ShouldCreateMemento(DirectHandle<JSObject> object);
 
  static const bool kCopying = true;
 
 private:
  Handle<AllocationSite> top_site_;
  bool activated_;
};
 
}  // namespace internal
}  // namespace v8
 
#endif  // V8_OBJECTS_ALLOCATION_SITE_SCOPES_H_