[js] Avoid %_ClassOf for collection builtins.

src/runtime/runtime-collections.cc

 // 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.
 
 #include "src/runtime/runtime-utils.h"
 
 #include "src/arguments.h"
 #include "src/conversions-inl.h"
 #include "src/factory.h"
 
@@ skipping 307 matching lines @@
 
 
 RUNTIME_FUNCTION(Runtime_GetWeakSetValues) {
   HandleScope scope(isolate);
   DCHECK_EQ(2, args.length());
   CONVERT_ARG_HANDLE_CHECKED(JSWeakCollection, holder, 0);
   CONVERT_NUMBER_CHECKED(int, max_values, Int32, args[1]);
   CHECK(max_values >= 0);
   return *JSWeakCollection::GetEntries(holder, max_values);
 }
+
+RUNTIME_FUNCTION(Runtime_IsJSMap) {
+  SealHandleScope shs(isolate);
+  DCHECK_EQ(1, args.length());
+  CONVERT_ARG_CHECKED(Object, obj, 0);
+  return isolate->heap()->ToBoolean(obj->IsJSMap());
+}
+
+RUNTIME_FUNCTION(Runtime_IsJSSet) {
+  SealHandleScope shs(isolate);
+  DCHECK_EQ(1, args.length());
+  CONVERT_ARG_CHECKED(Object, obj, 0);
+  return isolate->heap()->ToBoolean(obj->IsJSSet());
+}
+
+RUNTIME_FUNCTION(Runtime_IsJSMapIterator) {
+  SealHandleScope shs(isolate);
+  DCHECK_EQ(1, args.length());
+  CONVERT_ARG_CHECKED(Object, obj, 0);
+  return isolate->heap()->ToBoolean(obj->IsJSMapIterator());
+}
+
+RUNTIME_FUNCTION(Runtime_IsJSSetIterator) {
+  SealHandleScope shs(isolate);
+  DCHECK_EQ(1, args.length());
+  CONVERT_ARG_CHECKED(Object, obj, 0);
+  return isolate->heap()->ToBoolean(obj->IsJSSetIterator());
+}
+
+RUNTIME_FUNCTION(Runtime_IsJSWeakMap) {
+  SealHandleScope shs(isolate);
+  DCHECK_EQ(1, args.length());
+  CONVERT_ARG_CHECKED(Object, obj, 0);
+  return isolate->heap()->ToBoolean(obj->IsJSWeakMap());
+}
+
+RUNTIME_FUNCTION(Runtime_IsJSWeakSet) {
+  SealHandleScope shs(isolate);
+  DCHECK_EQ(1, args.length());
+  CONVERT_ARG_CHECKED(Object, obj, 0);
+  return isolate->heap()->ToBoolean(obj->IsJSWeakSet());
+}
+
 }  // namespace internal
 }  // namespace v8