v8-include.h.diff

--- deps/v8/include/v8.h	2017-05-06 20:26:52.304139042 +0200
+++ ../../v8-wrap/v8/include/v8.h	2017-05-04 16:28:42.456713336 +0200
@@ -128,7 +128,6 @@
 template<class T, class P> class WeakCallbackObject;
 class FunctionTemplate;
 class ObjectTemplate;
-class Data;
 template<typename T> class FunctionCallbackInfo;
 template<typename T> class PropertyCallbackInfo;
 class StackTrace;
@@ -151,6 +150,9 @@
 class GlobalHandles;
 }  // namespace internal
 
+namespace debug {
+class ConsoleCallArguments;
+}  // namespace debug
 
 // --- Handles ---
 
@@ -159,7 +161,6 @@
     *(static_cast<T* volatile*>(0)) = static_cast<S*>(0);      \
   }
 
-
 /**
  * An object reference managed by the v8 garbage collector.
  *
@@ -173,10 +174,16 @@
  * allocated on the heap.
  *
  * There are two types of handles: local and persistent handles.
+ *
  * Local handles are light-weight and transient and typically used in
- * local operations.  They are managed by HandleScopes.  Persistent
- * handles can be used when storing objects across several independent
- * operations and have to be explicitly deallocated when they're no
+ * local operations.  They are managed by HandleScopes. That means that a
+ * HandleScope must exist on the stack when they are created and that they are
+ * only valid inside of the HandleScope active during their creation.
+ * For passing a local handle to an outer HandleScope, an EscapableHandleScope
+ * and its Escape() method must be used.
+ *
+ * Persistent handles can be used when storing objects across several
+ * independent operations and have to be explicitly deallocated when they're no
  * longer used.
  *
  * It is safe to extract the object stored in the handle by
@@ -254,6 +261,11 @@
     return !operator==(that);
   }
 
+  /**
+   * Cast a handle to a subclass, e.g. Local<Value> to Local<Object>.
+   * This is only valid if the handle actually refers to a value of the
+   * target type.
+   */
   template <class S> V8_INLINE static Local<T> Cast(Local<S> that) {
 #ifdef V8_ENABLE_CHECKS
     // If we're going to perform the type check then we have to check
@@ -263,6 +275,11 @@
     return Local<T>(T::Cast(*that));
   }
 
+  /**
+   * Calling this is equivalent to Local<S>::Cast().
+   * In particular, this is only valid if the handle actually refers to a value
+   * of the target type.
+   */
   template <class S>
   V8_INLINE Local<S> As() const {
     return Local<S>::Cast(*this);
@@ -339,15 +356,26 @@
 
   V8_INLINE bool IsEmpty() const { return val_ == nullptr; }
 
+  /**
+   * Converts this MaybeLocal<> to a Local<>. If this MaybeLocal<> is empty,
+   * |false| is returned and |out| is left untouched.
+   */
   template <class S>
   V8_WARN_UNUSED_RESULT V8_INLINE bool ToLocal(Local<S>* out) const {
     out->val_ = IsEmpty() ? nullptr : this->val_;
     return !IsEmpty();
   }
 
-  // Will crash if the MaybeLocal<> is empty.
+  /**
+   * Converts this MaybeLocal<> to a Local<>. If this MaybeLocal<> is empty,
+   * V8 will crash the process.
+   */
   V8_INLINE Local<T> ToLocalChecked();
 
+  /**
+   * Converts this MaybeLocal<> to a Local<>, using a default value if this
+   * MaybeLocal<> is empty.
+   */
   template <class S>
   V8_INLINE Local<S> FromMaybe(Local<S> default_value) const {
     return IsEmpty() ? default_value : Local<S>(val_);
@@ -357,8 +385,10 @@
   T* val_;
 };
 
-
-// Eternal handles are set-once handles that live for the life of the isolate.
+/**
+ * Eternal handles are set-once handles that live for the lifetime of the
+ * isolate.
+ */
 template <class T> class Eternal {
  public:
   V8_INLINE Eternal() : val_(nullptr) {}
@@ -377,7 +407,7 @@
 
 
 static const int kInternalFieldsInWeakCallback = 2;
-
+static const int kEmbedderFieldsInWeakCallback = 2;
 
 template <typename T>
 class WeakCallbackInfo {
@@ -385,11 +415,11 @@
   typedef void (*Callback)(const WeakCallbackInfo<T>& data);
 
   WeakCallbackInfo(Isolate* isolate, T* parameter,
-                   void* internal_fields[kInternalFieldsInWeakCallback],
+                   void* embedder_fields[kEmbedderFieldsInWeakCallback],
                    Callback* callback)
       : isolate_(isolate), parameter_(parameter), callback_(callback) {
-    for (int i = 0; i < kInternalFieldsInWeakCallback; ++i) {
-      internal_fields_[i] = internal_fields[i];
+    for (int i = 0; i < kEmbedderFieldsInWeakCallback; ++i) {
+      embedder_fields_[i] = embedder_fields[i];
     }
   }
 
@@ -399,11 +429,11 @@
 
   V8_INLINE V8_DEPRECATED("use indexed version",
                           void* GetInternalField1() const) {
-    return internal_fields_[0];
+    return embedder_fields_[0];
   }
   V8_INLINE V8_DEPRECATED("use indexed version",
                           void* GetInternalField2() const) {
-    return internal_fields_[1];
+    return embedder_fields_[1];
   }
 
   V8_DEPRECATED("Not realiable once SetSecondPassCallback() was used.",
@@ -423,7 +453,7 @@
   Isolate* isolate_;
   T* parameter_;
   Callback* callback_;
-  void* internal_fields_[kInternalFieldsInWeakCallback];
+  void* embedder_fields_[kEmbedderFieldsInWeakCallback];
 };
 
 
@@ -438,10 +468,10 @@
  * An object reference that is independent of any handle scope.  Where
  * a Local handle only lives as long as the HandleScope in which it was
  * allocated, a PersistentBase handle remains valid until it is explicitly
- * disposed.
+ * disposed using Reset().
  *
  * A persistent handle contains a reference to a storage cell within
- * the v8 engine which holds an object value and which is updated by
+ * the V8 engine which holds an object value and which is updated by
  * the garbage collector whenever the object is moved.  A new storage
  * cell can be created using the constructor or PersistentBase::Reset and
  * existing handles can be disposed using PersistentBase::Reset.
@@ -899,6 +929,11 @@
   internal::Object** escape_slot_;
 };
 
+/**
+ * A SealHandleScope acts like a handle scope in which no handle allocations
+ * are allowed. It can be useful for debugging handle leaks.
+ * Handles can be allocated within inner normal HandleScopes.
+ */
 class V8_EXPORT SealHandleScope {
  public:
   SealHandleScope(Isolate* isolate);
@@ -1060,19 +1095,41 @@
   /**
    * ModuleDeclarationInstantiation
    *
-   * Returns false if an exception occurred during instantiation.
+   * Returns false if an exception occurred during instantiation. (In the case
+   * where the callback throws an exception, that exception is propagated.)
    */
   V8_WARN_UNUSED_RESULT bool Instantiate(Local<Context> context,
                                          ResolveCallback callback);
 
   /**
    * ModuleEvaluation
+   *
+   * Returns the completion value.
    */
   V8_WARN_UNUSED_RESULT MaybeLocal<Value> Evaluate(Local<Context> context);
 };
 
-// Node.js-specific: This will be implemented by a later V8 upgrade!
-class DynamicImportResult;
+/**
+ * This is an unfinished experimental feature, and is only exposed
+ * here for internal testing purposes. DO NOT USE.
+ *
+ * A compiled JavaScript module.
+ */
+class V8_EXPORT DynamicImportResult {
+ public:
+  /**
+   * Resolves the promise with the namespace object of the given
+   * module.
+   */
+  V8_WARN_UNUSED_RESULT bool FinishDynamicImportSuccess(Local<Context> context,
+                                                        Local<Module> module);
+
+  /**
+   * Rejects the promise with the given exception.
+   */
+  V8_WARN_UNUSED_RESULT bool FinishDynamicImportFailure(Local<Context> context,
+                                                        Local<Value> exception);
+};
 
 /**
  * A compiled JavaScript script, tied to a Context which was active when the
@@ -1364,7 +1421,7 @@
    * CachedData instance is still valid; the tag has no other meaing.
    *
    * Background: The data carried by CachedData may depend on the exact
-   *   V8 version number or currently compiler flags. This means when
+   *   V8 version number or current compiler flags. This means that when
    *   persisting CachedData, the embedder must take care to not pass in
    *   data from another V8 version, or the same version with different
    *   features enabled.
@@ -1615,6 +1672,11 @@
    * constructor via "new".
    */
   bool IsConstructor() const;
+
+  /**
+   * Returns whether or not the associated functions is defined in wasm.
+   */
+  bool IsWasm() const;
 };
 
 
@@ -1684,21 +1746,21 @@
    public:
     virtual ~Delegate() {}
 
-    /*
+    /**
      * Handles the case where a DataCloneError would be thrown in the structured
      * clone spec. Other V8 embedders may throw some other appropriate exception
      * type.
      */
     virtual void ThrowDataCloneError(Local<String> message) = 0;
 
-    /*
+    /**
      * The embedder overrides this method to write some kind of host object, if
      * possible. If not, a suitable exception should be thrown and
      * Nothing<bool>() returned.
      */
     virtual Maybe<bool> WriteHostObject(Isolate* isolate, Local<Object> object);
 
-    /*
+    /**
      * Called when the ValueSerializer is going to serialize a
      * SharedArrayBuffer object. The embedder must return an ID for the
      * object, using the same ID if this SharedArrayBuffer has already been
@@ -1713,7 +1775,7 @@
 
     virtual Maybe<uint32_t> GetWasmModuleTransferId(
         Isolate* isolate, Local<WasmCompiledModule> module);
-    /*
+    /**
      * Allocates memory for the buffer of at least the size provided. The actual
      * size (which may be greater or equal) is written to |actual_size|. If no
      * buffer has been allocated yet, nullptr will be provided.
@@ -1725,7 +1787,7 @@
     virtual void* ReallocateBufferMemory(void* old_buffer, size_t size,
                                          size_t* actual_size);
 
-    /*
+    /**
      * Frees a buffer allocated with |ReallocateBufferMemory|.
      */
     virtual void FreeBufferMemory(void* buffer);
@@ -1735,24 +1797,24 @@
   ValueSerializer(Isolate* isolate, Delegate* delegate);
   ~ValueSerializer();
 
-  /*
+  /**
    * Writes out a header, which includes the format version.
    */
   void WriteHeader();
 
-  /*
+  /**
    * Serializes a JavaScript value into the buffer.
    */
   V8_WARN_UNUSED_RESULT Maybe<bool> WriteValue(Local<Context> context,
                                                Local<Value> value);
 
-  /*
+  /**
    * Returns the stored data. This serializer should not be used once the buffer
    * is released. The contents are undefined if a previous write has failed.
    */
   V8_DEPRECATE_SOON("Use Release()", std::vector<uint8_t> ReleaseBuffer());
 
-  /*
+  /**
    * Returns the stored data (allocated using the delegate's
    * AllocateBufferMemory) and its size. This serializer should not be used once
    * the buffer is released. The contents are undefined if a previous write has
@@ -1760,7 +1822,7 @@
    */
   V8_WARN_UNUSED_RESULT std::pair<uint8_t*, size_t> Release();
 
-  /*
+  /**
    * Marks an ArrayBuffer as havings its contents transferred out of band.
    * Pass the corresponding ArrayBuffer in the deserializing context to
    * ValueDeserializer::TransferArrayBuffer.
@@ -1768,7 +1830,7 @@
   void TransferArrayBuffer(uint32_t transfer_id,
                            Local<ArrayBuffer> array_buffer);
 
-  /*
+  /**
    * Similar to TransferArrayBuffer, but for SharedArrayBuffer.
    */
   V8_DEPRECATE_SOON("Use Delegate::GetSharedArrayBufferId",
@@ -1776,7 +1838,7 @@
                         uint32_t transfer_id,
                         Local<SharedArrayBuffer> shared_array_buffer));
 
-  /*
+  /**
    * Indicate whether to treat ArrayBufferView objects as host objects,
    * i.e. pass them to Delegate::WriteHostObject. This should not be
    * called when no Delegate was passed.
@@ -1785,7 +1847,7 @@
    */
   void SetTreatArrayBufferViewsAsHostObjects(bool mode);
 
-  /*
+  /**
    * Write raw data in various common formats to the buffer.
    * Note that integer types are written in base-128 varint format, not with a
    * binary copy. For use during an override of Delegate::WriteHostObject.
@@ -1817,14 +1879,14 @@
    public:
     virtual ~Delegate() {}
 
-    /*
+    /**
      * The embedder overrides this method to read some kind of host object, if
      * possible. If not, a suitable exception should be thrown and
      * MaybeLocal<Object>() returned.
      */
     virtual MaybeLocal<Object> ReadHostObject(Isolate* isolate);
 
-    /*
+    /**
      * Get a WasmCompiledModule given a transfer_id previously provided
      * by ValueSerializer::GetWasmModuleTransferId
      */
@@ -1837,25 +1899,25 @@
                     Delegate* delegate);
   ~ValueDeserializer();
 
-  /*
+  /**
    * Reads and validates a header (including the format version).
    * May, for example, reject an invalid or unsupported wire format.
    */
   V8_WARN_UNUSED_RESULT Maybe<bool> ReadHeader(Local<Context> context);
 
-  /*
+  /**
    * Deserializes a JavaScript value from the buffer.
    */
   V8_WARN_UNUSED_RESULT MaybeLocal<Value> ReadValue(Local<Context> context);
 
-  /*
+  /**
    * Accepts the array buffer corresponding to the one passed previously to
    * ValueSerializer::TransferArrayBuffer.
    */
   void TransferArrayBuffer(uint32_t transfer_id,
                            Local<ArrayBuffer> array_buffer);
 
-  /*
+  /**
    * Similar to TransferArrayBuffer, but for SharedArrayBuffer.
    * The id is not necessarily in the same namespace as unshared ArrayBuffer
    * objects.
@@ -1863,7 +1925,7 @@
   void TransferSharedArrayBuffer(uint32_t id,
                                  Local<SharedArrayBuffer> shared_array_buffer);
 
-  /*
+  /**
    * Must be called before ReadHeader to enable support for reading the legacy
    * wire format (i.e., which predates this being shipped).
    *
@@ -1872,14 +1934,19 @@
    */
   void SetSupportsLegacyWireFormat(bool supports_legacy_wire_format);
 
-  /*
+  /**
+   * Expect inline wasm in the data stream (rather than in-memory transfer)
+   */
+  void SetExpectInlineWasm(bool allow_inline_wasm);
+
+  /**
    * Reads the underlying wire format version. Likely mostly to be useful to
    * legacy code reading old wire format versions. Must be called after
    * ReadHeader.
    */
   uint32_t GetWireFormatVersion() const;
 
-  /*
+  /**
    * Reads raw data in various common formats to the buffer.
    * Note that integer types are read in base-128 varint format, not with a
    * binary copy. For use during an override of Delegate::ReadHostObject.
@@ -1906,7 +1973,7 @@
  public:
   static Local<NativeWeakMap> New(Isolate* isolate);
   void Set(Local<Value> key, Local<Value> value);
-  Local<Value> Get(Local<Value> key);
+  Local<Value> Get(Local<Value> key) const;
   bool Has(Local<Value> key);
   bool Delete(Local<Value> key);
 };
@@ -2252,6 +2319,8 @@
 
   Local<String> TypeOf(Isolate*);
 
+  Maybe<bool> InstanceOf(Local<Context> context, Local<Object> object);
+
  private:
   V8_INLINE bool QuickIsUndefined() const;
   V8_INLINE bool QuickIsNull() const;
@@ -2304,9 +2373,25 @@
   static void CheckCast(Value* obj);
 };
 
+/**
+ * A flag describing different modes of string creation.
+ *
+ * Aside from performance implications there are no differences between the two
+ * creation modes.
+ */
+enum class NewStringType {
+  /**
+   * Create a new string, always allocating new storage memory.
+   */
+  kNormal,
 
-enum class NewStringType { kNormal, kInternalized };
-
+  /**
+   * Acts as a hint that the string should be created in the
+   * old generation heap space and be deduplicated if an identical string
+   * already exists.
+   */
+  kInternalized
+};
 
 /**
  * A JavaScript string value (ECMA-262, 4.3.17).
@@ -2321,7 +2406,7 @@
     ONE_BYTE_ENCODING = 0x8
   };
   /**
-   * Returns the number of characters in this string.
+   * Returns the number of characters (UTF-16 code units) in this string.
    */
   int Length() const;
 
@@ -2332,14 +2417,16 @@
   int Utf8Length() const;
 
   /**
-   * Returns whether this string is known to contain only one byte data.
+   * Returns whether this string is known to contain only one byte data,
+   * i.e. ISO-8859-1 code points.
    * Does not read the string.
    * False negatives are possible.
    */
   bool IsOneByte() const;
 
   /**
-   * Returns whether this string contain only one byte data.
+   * Returns whether this string contain only one byte data,
+   * i.e. ISO-8859-1 code points.
    * Will read the entire string in some cases.
    */
   bool ContainsOnlyOneByte() const;
@@ -2646,7 +2733,7 @@
   };
 
   /**
-   * Converts an object to a two-byte string.
+   * Converts an object to a two-byte (UTF-16-encoded) string.
    * If conversion to a string fails (eg. due to an exception in the toString()
    * method of the object) then the length() method returns 0 and the * operator
    * returns NULL.
@@ -2681,30 +2768,43 @@
  */
 class V8_EXPORT Symbol : public Name {
  public:
-  // Returns the print name string of the symbol, or undefined if none.
+  /**
+   * Returns the print name string of the symbol, or undefined if none.
+   */
   Local<Value> Name() const;
 
-  // Create a symbol. If name is not empty, it will be used as the description.
+  /**
+   * Create a symbol. If name is not empty, it will be used as the description.
+   */
   static Local<Symbol> New(Isolate* isolate,
                            Local<String> name = Local<String>());
 
-  // Access global symbol registry.
-  // Note that symbols created this way are never collected, so
-  // they should only be used for statically fixed properties.
-  // Also, there is only one global name space for the names used as keys.
-  // To minimize the potential for clashes, use qualified names as keys.
+  /**
+   * Access global symbol registry.
+   * Note that symbols created this way are never collected, so
+   * they should only be used for statically fixed properties.
+   * Also, there is only one global name space for the names used as keys.
+   * To minimize the potential for clashes, use qualified names as keys.
+   */
   static Local<Symbol> For(Isolate *isolate, Local<String> name);
 
-  // Retrieve a global symbol. Similar to |For|, but using a separate
-  // registry that is not accessible by (and cannot clash with) JavaScript code.
+  /**
+   * Retrieve a global symbol. Similar to |For|, but using a separate
+   * registry that is not accessible by (and cannot clash with) JavaScript code.
+   */
   static Local<Symbol> ForApi(Isolate *isolate, Local<String> name);
 
   // Well-known symbols
+  static Local<Symbol> GetHasInstance(Isolate* isolate);
+  static Local<Symbol> GetIsConcatSpreadable(Isolate* isolate);
   static Local<Symbol> GetIterator(Isolate* isolate);
-  static Local<Symbol> GetUnscopables(Isolate* isolate);
+  static Local<Symbol> GetMatch(Isolate* isolate);
+  static Local<Symbol> GetReplace(Isolate* isolate);
+  static Local<Symbol> GetSearch(Isolate* isolate);
+  static Local<Symbol> GetSplit(Isolate* isolate);
   static Local<Symbol> GetToPrimitive(Isolate* isolate);
   static Local<Symbol> GetToStringTag(Isolate* isolate);
-  static Local<Symbol> GetIsConcatSpreadable(Isolate* isolate);
+  static Local<Symbol> GetUnscopables(Isolate* isolate);
 
   V8_INLINE static Symbol* Cast(Value* obj);
 
@@ -2721,20 +2821,26 @@
  */
 class V8_EXPORT Private : public Data {
  public:
-  // Returns the print name string of the private symbol, or undefined if none.
+  /**
+   * Returns the print name string of the private symbol, or undefined if none.
+   */
   Local<Value> Name() const;
 
-  // Create a private symbol. If name is not empty, it will be the description.
+  /**
+   * Create a private symbol. If name is not empty, it will be the description.
+   */
   static Local<Private> New(Isolate* isolate,
                             Local<String> name = Local<String>());
 
-  // Retrieve a global private symbol. If a symbol with this name has not
-  // been retrieved in the same isolate before, it is created.
-  // Note that private symbols created this way are never collected, so
-  // they should only be used for statically fixed properties.
-  // Also, there is only one global name space for the names used as keys.
-  // To minimize the potential for clashes, use qualified names as keys,
-  // e.g., "Class#property".
+  /**
+   * Retrieve a global private symbol. If a symbol with this name has not
+   * been retrieved in the same isolate before, it is created.
+   * Note that private symbols created this way are never collected, so
+   * they should only be used for statically fixed properties.
+   * Also, there is only one global name space for the names used as keys.
+   * To minimize the potential for clashes, use qualified names as keys,
+   * e.g., "Class#property".
+   */
   static Local<Private> ForApi(Isolate* isolate, Local<String> name);
 
  private:
@@ -3000,15 +3106,16 @@
                                         Local<Value> key);
 
   V8_DEPRECATE_SOON("Use maybe version", bool Delete(Local<Value> key));
-  // TODO(dcarney): mark V8_WARN_UNUSED_RESULT
-  Maybe<bool> Delete(Local<Context> context, Local<Value> key);
+  V8_WARN_UNUSED_RESULT Maybe<bool> Delete(Local<Context> context,
+                                           Local<Value> key);
 
   V8_DEPRECATED("Use maybe version", bool Has(uint32_t index));
-  V8_WARN_UNUSED_RESULT Maybe<bool> Has(Local<Context> context, uint32_t index);
+  V8_WARN_UNUSED_RESULT Maybe<bool> Has(Local<Context> context,
+                                        uint32_t index);
 
   V8_DEPRECATED("Use maybe version", bool Delete(uint32_t index));
-  // TODO(dcarney): mark V8_WARN_UNUSED_RESULT
-  Maybe<bool> Delete(Local<Context> context, uint32_t index);
+  V8_WARN_UNUSED_RESULT Maybe<bool> Delete(Local<Context> context,
+                                           uint32_t index);
 
   V8_DEPRECATED("Use maybe version",
                 bool SetAccessor(Local<String> name,
@@ -3024,8 +3131,8 @@
                                  Local<Value> data = Local<Value>(),
                                  AccessControl settings = DEFAULT,
                                  PropertyAttribute attribute = None));
-  // TODO(dcarney): mark V8_WARN_UNUSED_RESULT
-  Maybe<bool> SetAccessor(Local<Context> context, Local<Name> name,
+  V8_WARN_UNUSED_RESULT Maybe<bool> SetAccessor(Local<Context> context,
+                          Local<Name> name,
                           AccessorNameGetterCallback getter,
                           AccessorNameSetterCallback setter = 0,
                           MaybeLocal<Value> data = MaybeLocal<Value>(),
@@ -3038,6 +3145,16 @@
                            AccessControl settings = DEFAULT);
 
   /**
+   * Sets a native data property like Template::SetNativeDataProperty, but
+   * this method sets on this object directly.
+   */
+  V8_WARN_UNUSED_RESULT Maybe<bool> SetNativeDataProperty(
+      Local<Context> context, Local<Name> name,
+      AccessorNameGetterCallback getter,
+      AccessorNameSetterCallback setter = nullptr,
+      Local<Value> data = Local<Value>(), PropertyAttribute attributes = None);
+
+  /**
    * Functionality for private properties.
    * This is an experimental feature, use at your own risk.
    * Note: Private properties are not inherited. Do not rely on this, since it
@@ -3515,6 +3632,7 @@
  protected:
   friend class internal::FunctionCallbackArguments;
   friend class internal::CustomArguments<FunctionCallbackInfo>;
+  friend class debug::ConsoleCallArguments;
   static const int kHolderIndex = 0;
   static const int kIsolateIndex = 1;
   static const int kReturnValueDefaultValueIndex = 2;
@@ -3775,12 +3893,12 @@
      * Ignored if the promise is no longer pending.
      */
     V8_DEPRECATE_SOON("Use maybe version", void Resolve(Local<Value> value));
-    // TODO(dcarney): mark V8_WARN_UNUSED_RESULT
-    Maybe<bool> Resolve(Local<Context> context, Local<Value> value);
+    V8_WARN_UNUSED_RESULT Maybe<bool> Resolve(Local<Context> context,
+                                              Local<Value> value);
 
     V8_DEPRECATE_SOON("Use maybe version", void Reject(Local<Value> value));
-    // TODO(dcarney): mark V8_WARN_UNUSED_RESULT
-    Maybe<bool> Reject(Local<Context> context, Local<Value> value);
+    V8_WARN_UNUSED_RESULT Maybe<bool> Reject(Local<Context> context,
+                                             Local<Value> value);
 
     V8_INLINE static Resolver* Cast(Value* obj);
 
@@ -3927,11 +4045,44 @@
   static void CheckCast(Value* obj);
 };
 
+// TODO(mtrofin): rename WasmCompiledModule to WasmModuleObject, for
+// consistency with internal APIs.
 class V8_EXPORT WasmCompiledModule : public Object {
  public:
   typedef std::pair<std::unique_ptr<const uint8_t[]>, size_t> SerializedModule;
   // A buffer that is owned by the caller.
   typedef std::pair<const uint8_t*, size_t> CallerOwnedBuffer;
+
+  // An opaque, native heap object for transferring wasm modules. It
+  // supports move semantics, and does not support copy semantics.
+  class TransferrableModule final {
+   public:
+    TransferrableModule(TransferrableModule&& src) = default;
+    TransferrableModule(const TransferrableModule& src) = delete;
+
+    TransferrableModule& operator=(TransferrableModule&& src) = default;
+    TransferrableModule& operator=(const TransferrableModule& src) = delete;
+
+   private:
+    typedef std::pair<std::unique_ptr<const uint8_t[]>, size_t> OwnedBuffer;
+    friend class WasmCompiledModule;
+    TransferrableModule(OwnedBuffer&& code, OwnedBuffer&& bytes)
+        : compiled_code(std::move(code)), wire_bytes(std::move(bytes)) {}
+
+    OwnedBuffer compiled_code = {nullptr, 0};
+    OwnedBuffer wire_bytes = {nullptr, 0};
+  };
+
+  // Get an in-memory, non-persistable, and context-independent (meaning,
+  // suitable for transfer to another Isolate and Context) representation
+  // of this wasm compiled module.
+  TransferrableModule GetTransferrableModule();
+
+  // Efficiently re-create a WasmCompiledModule, without recompiling, from
+  // a TransferrableModule.
+  static MaybeLocal<WasmCompiledModule> FromTransferrableModule(
+      Isolate* isolate, const TransferrableModule&);
+
   // Get the wasm-encoded bytes that were used to compile this module.
   Local<String> GetWasmWireBytes();
 
@@ -3947,16 +4098,49 @@
   V8_INLINE static WasmCompiledModule* Cast(Value* obj);
 
  private:
+  // TODO(ahaas): please remove the friend once streamed compilation is
+  // implemented
+  friend class WasmModuleObjectBuilder;
+
   static MaybeLocal<WasmCompiledModule> Deserialize(
       Isolate* isolate, const CallerOwnedBuffer& serialized_module,
       const CallerOwnedBuffer& wire_bytes);
   static MaybeLocal<WasmCompiledModule> Compile(Isolate* isolate,
                                                 const uint8_t* start,
                                                 size_t length);
+  static CallerOwnedBuffer AsCallerOwned(
+      const TransferrableModule::OwnedBuffer& buff) {
+    return {buff.first.get(), buff.second};
+  }
+
   WasmCompiledModule();
   static void CheckCast(Value* obj);
 };
 
+class V8_EXPORT WasmModuleObjectBuilder final {
+ public:
+  WasmModuleObjectBuilder(Isolate* isolate) : isolate_(isolate) {}
+  // The buffer passed into OnBytesReceived is owned by the caller.
+  void OnBytesReceived(const uint8_t*, size_t size);
+  MaybeLocal<WasmCompiledModule> Finish();
+
+ private:
+  Isolate* isolate_ = nullptr;
+  // TODO(ahaas): We probably need none of this below here once streamed
+  // compilation is implemented.
+  typedef std::pair<std::unique_ptr<const uint8_t[]>, size_t> Buffer;
+
+  // Disable copy semantics *in this implementation*. We can choose to
+  // relax this, albeit it's not clear why.
+  WasmModuleObjectBuilder(const WasmModuleObjectBuilder&) = delete;
+  WasmModuleObjectBuilder(WasmModuleObjectBuilder&&) = default;
+  WasmModuleObjectBuilder& operator=(const WasmModuleObjectBuilder&) = delete;
+  WasmModuleObjectBuilder& operator=(WasmModuleObjectBuilder&&) = default;
+
+  std::vector<Buffer> received_buffers_;
+  size_t total_size_ = 0;
+};
+
 #ifndef V8_ARRAY_BUFFER_INTERNAL_FIELD_COUNT
 // The number of required internal fields can be defined by embedder.
 #define V8_ARRAY_BUFFER_INTERNAL_FIELD_COUNT 2
@@ -4011,7 +4195,8 @@
     /**
      * malloc/free based convenience allocator.
      *
-     * Caller takes ownership.
+     * Caller takes ownership, i.e. the returned object needs to be freed using
+     * |delete allocator| once it is no longer in use.
      */
     static Allocator* NewDefaultAllocator();
   };
@@ -4055,8 +4240,11 @@
   /**
    * Create a new ArrayBuffer over an existing memory block.
    * The created array buffer is by default immediately in externalized state.
-   * The memory block will not be reclaimed when a created ArrayBuffer
-   * is garbage-collected.
+   * In externalized state, the memory block will not be reclaimed when a
+   * created ArrayBuffer is garbage-collected.
+   * In internalized state, the memory block will be released using
+   * |Allocator::Free| once all ArrayBuffers referencing it are collected by
+   * the garbage collector.
    */
   static Local<ArrayBuffer> New(
       Isolate* isolate, void* data, size_t byte_length,
@@ -4107,6 +4295,7 @@
   V8_INLINE static ArrayBuffer* Cast(Value* obj);
 
   static const int kInternalFieldCount = V8_ARRAY_BUFFER_INTERNAL_FIELD_COUNT;
+  static const int kEmbedderFieldCount = V8_ARRAY_BUFFER_INTERNAL_FIELD_COUNT;
 
  private:
   ArrayBuffer();
@@ -4160,6 +4349,8 @@
 
   static const int kInternalFieldCount =
       V8_ARRAY_BUFFER_VIEW_INTERNAL_FIELD_COUNT;
+  static const int kEmbedderFieldCount =
+      V8_ARRAY_BUFFER_VIEW_INTERNAL_FIELD_COUNT;
 
  private:
   ArrayBufferView();
@@ -4569,11 +4760,12 @@
    */
   enum Flags {
     kNone = 0,
-    kGlobal = 1,
-    kIgnoreCase = 2,
-    kMultiline = 4,
-    kSticky = 8,
-    kUnicode = 16
+    kGlobal = 1 << 0,
+    kIgnoreCase = 1 << 1,
+    kMultiline = 1 << 2,
+    kSticky = 1 << 3,
+    kUnicode = 1 << 4,
+    kDotAll = 1 << 5,
   };
 
   /**
@@ -4628,7 +4820,8 @@
   F(ArrayProto_entries, array_entries_iterator)  \
   F(ArrayProto_forEach, array_for_each_iterator) \
   F(ArrayProto_keys, array_keys_iterator)        \
-  F(ArrayProto_values, array_values_iterator)
+  F(ArrayProto_values, array_values_iterator)    \
+  F(IteratorPrototype, initial_iterator_prototype)
 
 enum Intrinsic {
 #define V8_DECL_INTRINSIC(name, iname) k##name,
@@ -5962,19 +6155,7 @@
 typedef bool (*AllowCodeGenerationFromStringsCallback)(Local<Context> context);
 
 // --- WASM compilation callbacks ---
-
-/**
- * Callback to check if a buffer source may be compiled to WASM, given
- * the compilation is attempted as a promise or not.
- */
-
-typedef bool (*AllowWasmCompileCallback)(Isolate* isolate, Local<Value> source,
-                                         bool as_promise);
-
-typedef bool (*AllowWasmInstantiateCallback)(Isolate* isolate,
-                                             Local<Value> module_or_bytes,
-                                             MaybeLocal<Value> ffi,
-                                             bool as_promise);
+typedef bool (*ExtensionCallback)(const FunctionCallbackInfo<Value>&);
 
 // --- Garbage Collection Callbacks ---
 
@@ -6037,6 +6218,11 @@
   size_t heap_size_limit() { return heap_size_limit_; }
   size_t malloced_memory() { return malloced_memory_; }
   size_t peak_malloced_memory() { return peak_malloced_memory_; }
+
+  /**
+   * Returns a 0/1 boolean, which signifies whether the V8 overwrite heap
+   * garbage with a bit pattern.
+   */
   size_t does_zap_garbage() { return does_zap_garbage_; }
 
  private:
@@ -6285,7 +6471,7 @@
    * wrappers from them when called through |AdvanceTracing|.
    */
   virtual void RegisterV8References(
-      const std::vector<std::pair<void*, void*> >& internal_fields) = 0;
+      const std::vector<std::pair<void*, void*> >& embedder_fields) = 0;
 
   /**
    * Called at the beginning of a GC cycle.
@@ -6348,6 +6534,9 @@
   CallbackFunction callback;
   void* data;
 };
+// Note that these fields are called "internal fields" in the API and called
+// "embedder fields" within V8.
+typedef SerializeInternalFieldsCallback SerializeEmbedderFieldsCallback;
 
 /**
  * Callback and supporting data used to implement embedder logic to deserialize
@@ -6363,6 +6552,7 @@
                    void* data);
   void* data;
 };
+typedef DeserializeInternalFieldsCallback DeserializeEmbedderFieldsCallback;
 
 /**
  * Isolate represents an isolated instance of the V8 engine.  V8 isolates have
@@ -6394,8 +6584,9 @@
      * The optional entry_hook allows the host application to provide the
      * address of a function that's invoked on entry to every V8-generated
      * function.  Note that entry_hook is invoked at the very start of each
-     * generated function. Furthermore, if an entry_hook is given, V8 will
-     * not use a snapshot, including custom snapshots.
+     * generated function.
+     * An entry_hook can only be provided in no-snapshot builds; in snapshot
+     * builds it must be nullptr.
      */
     FunctionEntryHook entry_hook;
 
@@ -6447,7 +6638,7 @@
 
     /**
      * Whether calling Atomics.wait (a function that may block) is allowed in
-     * this isolate.
+     * this isolate. This can also be configured via SetAllowAtomicsWait.
      */
     bool allow_atomics_wait;
 
@@ -6686,6 +6877,12 @@
   void Dispose();
 
   /**
+   * Dumps activated low-level V8 internal stats. This can be used instead
+   * of performing a full isolate disposal.
+   */
+  void DumpAndResetStats();
+
+  /**
    * Discards all V8 thread-specific data for the Isolate. Should be used
    * if a thread is terminating and it has used an Isolate that will outlive
    * the thread -- all thread-specific data for an Isolate is discarded when
@@ -7210,6 +7407,14 @@
       AllowCodeGenerationFromStringsCallback callback);
 
   /**
+   * Embedder over{ride|load} injection points for wasm APIs.
+   */
+  void SetWasmModuleCallback(ExtensionCallback callback);
+  void SetWasmCompileCallback(ExtensionCallback callback);
+  void SetWasmInstanceCallback(ExtensionCallback callback);
+  void SetWasmInstantiateCallback(ExtensionCallback callback);
+
+  /**
   * Check if V8 is dead and therefore unusable.  This is the case after
   * fatal errors such as out-of-memory situations.
   */
@@ -7293,6 +7498,13 @@
    */
   bool IsInUse();
 
+  /**
+   * Set whether calling Atomics.wait (a function that may block) is allowed in
+   * this isolate. This can also be configured via
+   * CreateParams::allow_atomics_wait.
+   */
+  void SetAllowAtomicsWait(bool allow);
+
   Isolate() = delete;
   ~Isolate() = delete;
   Isolate(const Isolate&) = delete;
@@ -7664,6 +7876,35 @@
    */
   static void ShutdownPlatform();
 
+#if V8_OS_LINUX && V8_TARGET_ARCH_X64 && !V8_OS_ANDROID
+  /**
+   * Give the V8 signal handler a chance to handle a fault.
+   *
+   * This function determines whether a memory access violation can be recovered
+   * by V8. If so, it will return true and modify context to return to a code
+   * fragment that can recover from the fault. Otherwise, TryHandleSignal will
+   * return false.
+   *
+   * The parameters to this function correspond to those passed to a Linux
+   * signal handler.
+   *
+   * \param signal_number The signal number.
+   *
+   * \param info A pointer to the siginfo_t structure provided to the signal
+   * handler.
+   *
+   * \param context The third argument passed to the Linux signal handler, which
+   * points to a ucontext_t structure.
+   */
+  static bool TryHandleSignal(int signal_number, void* info, void* context);
+#endif  // V8_OS_LINUX
+
+  /**
+   * Enable the default signal handler rather than using one provided by the
+   * embedder.
+   */
+  static bool RegisterDefaultSignalHandler();
+
  private:
   V8();
 
@@ -7790,20 +8031,33 @@
   V8_INLINE bool IsNothing() const { return !has_value_; }
   V8_INLINE bool IsJust() const { return has_value_; }
 
-  // Will crash if the Maybe<> is nothing.
+  /**
+   * An alias for |FromJust|. Will crash if the Maybe<> is nothing.
+   */
   V8_INLINE T ToChecked() const { return FromJust(); }
 
+  /**
+   * Converts this Maybe<> to a value of type T. If this Maybe<> is
+   * nothing (empty), |false| is returned and |out| is left untouched.
+   */
   V8_WARN_UNUSED_RESULT V8_INLINE bool To(T* out) const {
     if (V8_LIKELY(IsJust())) *out = value_;
     return IsJust();
   }
 
-  // Will crash if the Maybe<> is nothing.
+  /**
+   * Converts this Maybe<> to a value of type T. If this Maybe<> is
+   * nothing (empty), V8 will crash the process.
+   */
   V8_INLINE T FromJust() const {
     if (V8_UNLIKELY(!IsJust())) V8::FromJustIsNothing();
     return value_;
   }
 
+  /**
+   * Converts this Maybe<> to a value of type T, using a default value if this
+   * Maybe<> is nothing (empty).
+   */
   V8_INLINE T FromMaybe(const T& default_value) const {
     return has_value_ ? value_ : default_value;
   }
@@ -7953,6 +8207,11 @@
   void SetVerbose(bool value);
 
   /**
+   * Returns true if verbosity is enabled.
+   */
+  bool IsVerbose() const;
+
+  /**
    * Set whether or not this TryCatch should capture a Message object
    * which holds source information about where the exception
    * occurred.  True by default.
@@ -8077,7 +8336,7 @@
    * \param context_snapshot_index The index of the context snapshot to
    * deserialize from. Use v8::Context::New for the default snapshot.
    *
-   * \param internal_fields_deserializer Optional callback to deserialize
+   * \param embedder_fields_deserializer Optional callback to deserialize
    * internal fields. It should match the SerializeInternalFieldCallback used
    * to serialize.
    *
@@ -8088,7 +8347,7 @@
 
   static MaybeLocal<Context> FromSnapshot(
       Isolate* isolate, size_t context_snapshot_index,
-      DeserializeInternalFieldsCallback internal_fields_deserializer =
+      DeserializeInternalFieldsCallback embedder_fields_deserializer =
           DeserializeInternalFieldsCallback(),
       ExtensionConfiguration* extensions = nullptr,
       MaybeLocal<Value> global_object = MaybeLocal<Value>());
@@ -8144,16 +8403,14 @@
   Isolate* GetIsolate();
 
   /**
-   * The field at kDebugIdIndex is reserved for V8 debugger implementation.
-   * The value is propagated to the scripts compiled in given Context and
-   * can be used for filtering scripts.
+   * The field at kDebugIdIndex used to be reserved for the inspector.
+   * It now serves no purpose.
    */
   enum EmbedderDataFields { kDebugIdIndex = 0 };
 
   /**
    * Gets the embedder data with the given index, which must have been set by a
-   * previous call to SetEmbedderData with the same index. Note that index 0
-   * currently has a special meaning for Chrome's debugger.
+   * previous call to SetEmbedderData with the same index.
    */
   V8_INLINE Local<Value> GetEmbedderData(int index);
 
@@ -8669,11 +8926,11 @@
 template <class T>
 void* WeakCallbackInfo<T>::GetInternalField(int index) const {
 #ifdef V8_ENABLE_CHECKS
-  if (index < 0 || index >= kInternalFieldsInWeakCallback) {
+  if (index < 0 || index >= kEmbedderFieldsInWeakCallback) {
     V8::InternalFieldOutOfBounds(index);
   }
 #endif
-  return internal_fields_[index];
+  return embedder_fields_[index];
 }