Remove LookupTransitionOrDescriptor altogether.

src/hydrogen-instructions.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 1652 matching lines @@
 }
 
 
 void HLoadNamedField::PrintDataTo(StringStream* stream) {
   object()->PrintNameTo(stream);
   stream->Add(" @%d%s", offset(), is_in_object() ? "[in-object]" : "");
 }
 
 
 // Returns true if an instance of this map can never find a property with this
-// name in its prototype chain.  This means all prototypes up to the top are
-// fast and don't have the name in them.  It would be good if we could optimize
+// name in its prototype chain. This means all prototypes up to the top are fast
+// and don't have the name in them. It would be good if we could optimize
 // polymorphic loads where the property is sometimes found in the prototype
 // chain.
 static bool PrototypeChainCanNeverResolve(
     Handle<Map> map, Handle<String> name) {
   Isolate* isolate = map->GetIsolate();
   Object* current = map->prototype();
   while (current != isolate->heap()->null_value()) {
     if (current->IsJSGlobalProxy() ||
         current->IsGlobalObject() ||
         !current->IsJSObject() ||
         JSObject::cast(current)->IsAccessCheckNeeded() ||
         !JSObject::cast(current)->HasFastProperties()) {
       return false;
     }
 
     LookupResult lookup(isolate);
     Map* map = JSObject::cast(current)->map();
-    map->LookupTransitionOrDescriptor(NULL, *name, &lookup);
-    if (lookup.IsFound()) {
-      if (!lookup.IsTransition()) return false;
-    } else if (!lookup.IsCacheable()) {
-      return false;
-    }
-
+    map->LookupDescriptor(NULL, *name, &lookup);
+    if (lookup.IsFound()) return false;
+    if (!lookup.IsCacheable()) return false;
     current = JSObject::cast(current)->GetPrototype();
   }
   return true;
 }
 
 
 HLoadNamedFieldPolymorphic::HLoadNamedFieldPolymorphic(HValue* context,
                                                        HValue* object,
                                                        SmallMapList* types,
                                                        Handle<String> name,
                                                        Zone* zone)
     : types_(Min(types->length(), kMaxLoadPolymorphism), zone),
       name_(name),
       need_generic_(false) {
   SetOperandAt(0, context);
   SetOperandAt(1, object);
   set_representation(Representation::Tagged());
   SetGVNFlag(kDependsOnMaps);
   SmallMapList negative_lookups;
   for (int i = 0;
        i < types->length() && types_.length() < kMaxLoadPolymorphism;
        ++i) {
     Handle<Map> map = types->at(i);
     LookupResult lookup(map->GetIsolate());
-    map->LookupTransitionOrDescriptor(NULL, *name, &lookup);
+    map->LookupDescriptor(NULL, *name, &lookup);
     if (lookup.IsFound()) {
       switch (lookup.type()) {
         case FIELD: {
           int index = lookup.GetLocalFieldIndexFromMap(*map);
           if (index < 0) {
             SetGVNFlag(kDependsOnInobjectFields);
           } else {
             SetGVNFlag(kDependsOnBackingStoreFields);
           }
           types_.Add(types->at(i), zone);
           break;
         }
         case CONSTANT_FUNCTION:
           types_.Add(types->at(i), zone);
           break;
         case CALLBACKS:
           break;
         case TRANSITION:
-          if (PrototypeChainCanNeverResolve(map, name)) {
-            negative_lookups.Add(types->at(i), zone);
-          }
-          break;
         case INTERCEPTOR:
         case NONEXISTENT:
         case NORMAL:
         case HANDLER:
           UNREACHABLE();
           break;
       }
-    } else if (lookup.IsCacheable()) {
-      if (PrototypeChainCanNeverResolve(map, name)) {
-        negative_lookups.Add(types->at(i), zone);
-      }
+    } else if (lookup.IsCacheable() &&
+               PrototypeChainCanNeverResolve(map, name)) {
+      negative_lookups.Add(types->at(i), zone);
     }
   }
 
   bool need_generic =
       (types->length() != negative_lookups.length() + types_.length());
   if (!need_generic && FLAG_deoptimize_uncommon_cases) {
     SetFlag(kUseGVN);
     for (int i = 0; i < negative_lookups.length(); i++) {
       types_.Add(negative_lookups.at(i), zone);
     }
@@ skipping 822 matching lines @@
 
 
 void HCheckPrototypeMaps::Verify() {
   HInstruction::Verify();
   ASSERT(HasNoUses());
 }
 
 #endif
 
 } }  // namespace v8::internal