[esnext] prototype runtime implementation for async functions

src/objects-inl.h

 // 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.
 //
 // Review notes:
 //
 // - The use of macros in these inline functions may seem superfluous
 // but it is absolutely needed to make sure gcc generates optimal
 // code. gcc is not happy when attempting to inline too deep.
 //
@@ skipping 5768 matching lines @@
                name_should_print_as_anonymous,
                kNameShouldPrintAsAnonymous)
 BOOL_ACCESSORS(SharedFunctionInfo, compiler_hints, is_anonymous_expression,
                kIsAnonymousExpression)
 BOOL_ACCESSORS(SharedFunctionInfo, compiler_hints, is_function, kIsFunction)
 BOOL_ACCESSORS(SharedFunctionInfo, compiler_hints, dont_crankshaft,
                kDontCrankshaft)
 BOOL_ACCESSORS(SharedFunctionInfo, compiler_hints, dont_flush, kDontFlush)
 BOOL_ACCESSORS(SharedFunctionInfo, compiler_hints, is_arrow, kIsArrow)
 BOOL_ACCESSORS(SharedFunctionInfo, compiler_hints, is_generator, kIsGenerator)
+BOOL_ACCESSORS(SharedFunctionInfo, compiler_hints, is_async, kIsAsyncFunction)
 BOOL_ACCESSORS(SharedFunctionInfo, compiler_hints, is_concise_method,
                kIsConciseMethod)
 BOOL_ACCESSORS(SharedFunctionInfo, compiler_hints, is_getter_function,
                kIsGetterFunction)
 BOOL_ACCESSORS(SharedFunctionInfo, compiler_hints, is_setter_function,
                kIsSetterFunction)
 BOOL_ACCESSORS(SharedFunctionInfo, compiler_hints, is_default_constructor,
                kIsDefaultConstructor)
 
+inline bool SharedFunctionInfo::is_resumable() const {
+  return is_generator() || is_async();
+}
+
 bool Script::HasValidSource() {
   Object* src = this->source();
   if (!src->IsString()) return true;
   String* src_str = String::cast(src);
   if (!StringShape(src_str).IsExternal()) return true;
   if (src_str->IsOneByteRepresentation()) {
     return ExternalOneByteString::cast(src)->resource() != NULL;
   } else if (src_str->IsTwoByteRepresentation()) {
     return ExternalTwoByteString::cast(src)->resource() != NULL;
   }
@@ skipping 2043 matching lines @@
 #undef WRITE_INT64_FIELD
 #undef READ_BYTE_FIELD
 #undef WRITE_BYTE_FIELD
 #undef NOBARRIER_READ_BYTE_FIELD
 #undef NOBARRIER_WRITE_BYTE_FIELD
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_OBJECTS_INL_H_