deps: update V8 to 7.6.303.28

PR-URL: https://github.com/nodejs/node/pull/28016
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Refael Ackermann (רפאל פלחי) <refack@gmail.com>
Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: Michael Dawson <michael_dawson@ca.ibm.com>
Reviewed-By: Jiawen Geng <technicalcute@gmail.com>

1 files changed, 89 insertions, 0 deletions

diff --git a/deps/v8/src/objects/prototype.h b/deps/v8/src/objects/prototype.h
new file mode 100644
index 0000000000..cd003837ca
--- /dev/null
+++ b/deps/v8/src/objects/prototype.h
@@ -0,0 +1,89 @@
+// Copyright 2014 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_PROTOTYPE_H_
+#define V8_OBJECTS_PROTOTYPE_H_
+
+#include "src/execution/isolate.h"
+#include "src/objects/objects.h"
+
+namespace v8 {
+namespace internal {
+
+/**
+ * A class to uniformly access the prototype of any Object and walk its
+ * prototype chain.
+ *
+ * The PrototypeIterator can either start at the prototype (default), or
+ * include the receiver itself. If a PrototypeIterator is constructed for a
+ * Map, it will always start at the prototype.
+ *
+ * The PrototypeIterator can either run to the null_value(), the first
+ * non-hidden prototype, or a given object.
+ */
+
+class PrototypeIterator {
+ public:
+  enum WhereToEnd { END_AT_NULL, END_AT_NON_HIDDEN };
+
+  inline PrototypeIterator(Isolate* isolate, Handle<JSReceiver> receiver,
+                           WhereToStart where_to_start = kStartAtPrototype,
+                           WhereToEnd where_to_end = END_AT_NULL);
+
+  inline PrototypeIterator(Isolate* isolate, JSReceiver receiver,
+                           WhereToStart where_to_start = kStartAtPrototype,
+                           WhereToEnd where_to_end = END_AT_NULL);
+
+  inline explicit PrototypeIterator(Isolate* isolate, Map receiver_map,
+                                    WhereToEnd where_to_end = END_AT_NULL);
+
+  inline explicit PrototypeIterator(Isolate* isolate, Handle<Map> receiver_map,
+                                    WhereToEnd where_to_end = END_AT_NULL);
+
+  ~PrototypeIterator() = default;
+
+  inline bool HasAccess() const;
+
+  template <typename T = HeapObject>
+  T GetCurrent() const {
+    DCHECK(handle_.is_null());
+    return T::cast(object_);
+  }
+
+  template <typename T = HeapObject>
+  static Handle<T> GetCurrent(const PrototypeIterator& iterator) {
+    DCHECK(!iterator.handle_.is_null());
+    DCHECK_EQ(iterator.object_, Object());
+    return Handle<T>::cast(iterator.handle_);
+  }
+
+  inline void Advance();
+
+  inline void AdvanceIgnoringProxies();
+
+  // Returns false iff a call to JSProxy::GetPrototype throws.
+  V8_WARN_UNUSED_RESULT inline bool AdvanceFollowingProxies();
+
+  V8_WARN_UNUSED_RESULT inline bool
+  AdvanceFollowingProxiesIgnoringAccessChecks();
+
+  bool IsAtEnd() const { return is_at_end_; }
+  Isolate* isolate() const { return isolate_; }
+
+ private:
+  Isolate* isolate_;
+  Object object_;
+  Handle<HeapObject> handle_;
+  WhereToEnd where_to_end_;
+  bool is_at_end_;
+  int seen_proxies_;
+
+  DISALLOW_COPY_AND_ASSIGN(PrototypeIterator);
+};
+
+}  // namespace internal
+
+}  // namespace v8
+
+#endif  // V8_OBJECTS_PROTOTYPE_H_