Reland Create JSPromise (patchset #16 id:300001 of https://codereview.chromium.org/2536463002/ )"

src/objects.h

 // Copyright 2015 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_H_
 #define V8_OBJECTS_H_
 
 #include <iosfwd>
 #include <memory>
 
@@ skipping 8877 matching lines @@
   static const int kStackFramesOffset = kScriptOffset + kPointerSize;
   static const int kStartPositionOffset = kStackFramesOffset + kPointerSize;
   static const int kEndPositionOffset = kStartPositionOffset + kPointerSize;
   static const int kSize = kEndPositionOffset + kPointerSize;
 
   typedef FixedBodyDescriptor<HeapObject::kMapOffset,
                               kStackFramesOffset + kPointerSize,
                               kSize> BodyDescriptor;
 };
 
+class JSPromise : public JSObject {
+ public:
+  DECL_INT_ACCESSORS(status)
+  DECL_ACCESSORS(result, Object)
+
+  // There are 3 possible states for these fields --
+  // 1) Undefined -- This is the zero state when there is no callback
+  // or deferred registered.
+  // 2) Object -- There is a single Callable directly attached to the
+  // fulfill_reactions, reject_reactions and the deferred JSObject is
+  // directly attached to the deferred field.
+  // 3) FixedArray -- There is more than one callback and deferred
+  // attached to a FixedArray.
+  DECL_ACCESSORS(deferred, Object)
+  DECL_ACCESSORS(fulfill_reactions, Object)
+  DECL_ACCESSORS(reject_reactions, Object)
+
+  static const char* Status(int status);
+
+  DECLARE_CAST(JSPromise)
+
+  // Dispatched behavior.
+  DECLARE_PRINTER(JSPromise)
+  DECLARE_VERIFIER(JSPromise)
+
+  // Layout description.
+  static const int kStatusOffset = JSObject::kHeaderSize;
+  static const int kResultOffset = kStatusOffset + kPointerSize;
+  static const int kDeferredOffset = kResultOffset + kPointerSize;
+  static const int kFulfillReactionsOffset = kDeferredOffset + kPointerSize;
+  static const int kRejectReactionsOffset =
+      kFulfillReactionsOffset + kPointerSize;
+  static const int kSize = kRejectReactionsOffset + kPointerSize;
+};
+
 // Regular expressions
 // The regular expression holds a single reference to a FixedArray in
 // the kDataOffset field.
 // The FixedArray contains the following data:
 // - tag : type of regexp implementation (not compiled yet, atom or irregexp)
 // - reference to the original source string
 // - reference to the original flag string
 // If it is an atom regexp
 // - a reference to a literal string to search for
 // If it is an irregexp regexp:
@@ skipping 3045 matching lines @@
     }
     return value;
   }
 };
 
 
 }  // NOLINT, false-positive due to second-order macros.
 }  // NOLINT, false-positive due to second-order macros.
 
 #endif  // V8_OBJECTS_H_