Speed up ArrayBuffer/typed array/DataView properties.

src/ic.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 1330 matching lines @@
         return isolate()->stub_cache()->ComputeLoadGlobal(
             name, receiver, global, cell, lookup->IsDontDelete());
       }
       // There is only one shared stub for loading normalized
       // properties. It does not traverse the prototype chain, so the
       // property must be found in the receiver for the stub to be
       // applicable.
       if (!holder.is_identical_to(receiver)) break;
       return isolate()->stub_cache()->ComputeLoadNormal(name, receiver);
     case CALLBACKS: {
-      Handle<Object> callback(lookup->GetCallbackObject(), isolate());
-      if (name->Equals(isolate()->heap()->length_string())) {
-        if (receiver->IsJSArray()) {
-          PropertyIndex lengthIndex = PropertyIndex::NewHeaderIndex(
-              JSArray::kLengthOffset / kPointerSize);
+      {

[Toon Verwaest, 2013/09/24 15:37:38]

Remove extra { .. }

+        // Use simple field loads for some well-known callback properties.
+        int object_offset;
+        Handle<Map> map(receiver->map());
+        if (Accessors::IsJSObjectFieldAccessor(map, name, &object_offset)) {
+          PropertyIndex index =
+              PropertyIndex::NewHeaderIndex(object_offset / kPointerSize);
           return isolate()->stub_cache()->ComputeLoadField(
-              name, receiver, receiver, lengthIndex, Representation::Tagged());
-        } else if (receiver->IsJSTypedArray()) {
-          PropertyIndex lengthIndex = PropertyIndex::NewHeaderIndex(
-              JSTypedArray::kLengthOffset / kPointerSize);
-          return isolate()->stub_cache()->ComputeLoadField(
-              name, receiver, receiver, lengthIndex, Representation::Tagged());
+              name, receiver, receiver, index, Representation::Tagged());
         }
       }
+
+      Handle<Object> callback(lookup->GetCallbackObject(), isolate());
       if (callback->IsExecutableAccessorInfo()) {
         Handle<ExecutableAccessorInfo> info =
             Handle<ExecutableAccessorInfo>::cast(callback);
         if (v8::ToCData<Address>(info->getter()) == 0) break;
         if (!info->IsCompatibleReceiver(*receiver)) break;
         return isolate()->stub_cache()->ComputeLoadCallback(
             name, receiver, holder, info);
       } else if (callback->IsAccessorPair()) {
         Handle<Object> getter(Handle<AccessorPair>::cast(callback)->getter(),
                               isolate());
@@ skipping 1788 matching lines @@
 #undef ADDR
 };
 
 
 Address IC::AddressFromUtilityId(IC::UtilityId id) {
   return IC_utilities[id];
 }
 
 
 } }  // namespace v8::internal