[turbofan] Introduce map-guarded generic handler for named store.

src/compiler/access-info.cc

 // 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.
 
 #include <ostream>
 
 #include "src/accessors.h"
 #include "src/compilation-dependencies.h"
 #include "src/compiler/access-info.h"
 #include "src/compiler/type-cache.h"
@@ skipping 76 matching lines @@
                             receiver_maps);
 }
 
 // static
 PropertyAccessInfo PropertyAccessInfo::AccessorConstant(
     MapList const& receiver_maps, Handle<Object> constant,
     MaybeHandle<JSObject> holder) {
   return PropertyAccessInfo(kAccessorConstant, holder, constant, receiver_maps);
 }
 
+// static
+PropertyAccessInfo PropertyAccessInfo::Generic(MapList const& receiver_maps) {
+  return PropertyAccessInfo(kGeneric, MaybeHandle<JSObject>(), Handle<Object>(),
+                            receiver_maps);
+}
+
 PropertyAccessInfo::PropertyAccessInfo()
     : kind_(kInvalid),
       field_representation_(MachineRepresentation::kNone),
       field_type_(Type::None()) {}
 
 PropertyAccessInfo::PropertyAccessInfo(MaybeHandle<JSObject> holder,
                                        MapList const& receiver_maps)
     : kind_(kNotFound),
       receiver_maps_(receiver_maps),
       holder_(holder),
@@ skipping 53 matching lines @@
     case kAccessorConstant: {
       // Check if we actually access the same constant.
       if (this->constant_.address() == that->constant_.address()) {
         this->receiver_maps_.insert(this->receiver_maps_.end(),
                                     that->receiver_maps_.begin(),
                                     that->receiver_maps_.end());
         return true;
       }
       return false;
     }
+    case kGeneric: {
+      this->receiver_maps_.insert(this->receiver_maps_.end(),
+                                  that->receiver_maps_.begin(),
+                                  that->receiver_maps_.end());
+      return true;
+    }
   }
 
   UNREACHABLE();
   return false;
 }
 
 AccessInfoFactory::AccessInfoFactory(CompilationDependencies* dependencies,
                                      Handle<Context> native_context, Zone* zone)
     : dependencies_(dependencies),
       native_context_(native_context),
@@ skipping 291 matching lines @@
     return true;
   }
   return false;
 }
 
 
 bool AccessInfoFactory::LookupTransition(Handle<Map> map, Handle<Name> name,
                                          MaybeHandle<JSObject> holder,
                                          PropertyAccessInfo* access_info) {
   // Check if the {map} has a data transition with the given {name}.
-  if (map->unused_property_fields() == 0) return false;
+  if (map->unused_property_fields() == 0) {
+    *access_info = PropertyAccessInfo::Generic(MapList{map});
+    return true;
+  }
   Handle<Map> transition_map;
   if (TransitionArray::SearchTransition(map, kData, name, NONE)
           .ToHandle(&transition_map)) {
     int const number = transition_map->LastAdded();
     PropertyDetails const details =
         transition_map->instance_descriptors()->GetDetails(number);
     // Don't bother optimizing stores to read-only properties.
     if (details.IsReadOnly()) return false;
     // TODO(bmeurer): Handle transition to data constant?
     if (details.type() != DATA) return false;
@@ skipping 39 matching lines @@
   }
   return false;
 }
 
 
 Factory* AccessInfoFactory::factory() const { return isolate()->factory(); }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8