Make the typefeedback oracle use a NumberDictionary instead of JSObject as it...

src/type-info.cc

 // Copyright 2010 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 46 matching lines @@
   return info;
 }
 
 
 STATIC_ASSERT(DEFAULT_STRING_STUB == Code::kNoExtraICState);
 
 
 TypeFeedbackOracle::TypeFeedbackOracle(Handle<Code> code,
                                        Handle<Context> global_context) {
   global_context_ = global_context;
-  Initialize(code);
+  PopulateMap(code);
+  ASSERT(reinterpret_cast<Address>(*dictionary_.location()) != kHandleZapValue);
 }
 
 
-void TypeFeedbackOracle::Initialize(Handle<Code> code) {
-  ASSERT(map_.is_null());  // Only initialize once.
-  map_ = Factory::NewJSObject(Top::object_function());
-  PopulateMap(code);
+Handle<Object> TypeFeedbackOracle::GetInfo(int pos) {
+  int entry = dictionary_->FindEntry(pos);
+  return entry != NumberDictionary::kNotFound
+      ? Handle<Object>(dictionary_->ValueAt(entry))
+      : Factory::undefined_value();
 }
 
 
 bool TypeFeedbackOracle::LoadIsMonomorphic(Property* expr) {
-  return GetElement(map_, expr->position())->IsMap();
+  return GetInfo(expr->position())->IsMap();
 }
 
 
 bool TypeFeedbackOracle:: StoreIsMonomorphic(Assignment* expr) {
-  return GetElement(map_, expr->position())->IsMap();
+  return GetInfo(expr->position())->IsMap();
 }
 
 
 bool TypeFeedbackOracle::CallIsMonomorphic(Call* expr) {
-  Handle<Object> value = GetElement(map_, expr->position());
+  Handle<Object> value = GetInfo(expr->position());
   return value->IsMap() || value->IsSmi();
 }
 
 
 Handle<Map> TypeFeedbackOracle::LoadMonomorphicReceiverType(Property* expr) {
   ASSERT(LoadIsMonomorphic(expr));
-  return Handle<Map>::cast(GetElement(map_, expr->position()));
+  return Handle<Map>::cast(GetInfo(expr->position()));
 }
 
 
 Handle<Map> TypeFeedbackOracle::StoreMonomorphicReceiverType(Assignment* expr) {
   ASSERT(StoreIsMonomorphic(expr));
-  return Handle<Map>::cast(GetElement(map_, expr->position()));
+  return Handle<Map>::cast(GetInfo(expr->position()));
 }
 
 
 ZoneMapList* TypeFeedbackOracle::LoadReceiverTypes(Property* expr,
                                                    Handle<String> name) {
   Code::Flags flags = Code::ComputeMonomorphicFlags(Code::LOAD_IC, NORMAL);
   return CollectReceiverTypes(expr->position(), name, flags);
 }
 
 
@@ skipping 15 matching lines @@
                                                     NORMAL,
                                                     Code::kNoExtraICState,
                                                     OWN_MAP,
                                                     NOT_IN_LOOP,
                                                     arity);
   return CollectReceiverTypes(expr->position(), name, flags);
 }
 
 
 CheckType TypeFeedbackOracle::GetCallCheckType(Call* expr) {
-  Handle<Object> value = GetElement(map_, expr->position());
+  Handle<Object> value = GetInfo(expr->position());
   if (!value->IsSmi()) return RECEIVER_MAP_CHECK;
   CheckType check = static_cast<CheckType>(Smi::cast(*value)->value());
   ASSERT(check != RECEIVER_MAP_CHECK);
   return check;
 }
 
 
 Handle<JSObject> TypeFeedbackOracle::GetPrototypeForPrimitiveCheck(
     CheckType check) {
   JSFunction* function = NULL;
@@ skipping 10 matching lines @@
     case BOOLEAN_CHECK:
       function = global_context_->boolean_function();
       break;
   }
   ASSERT(function != NULL);
   return Handle<JSObject>(JSObject::cast(function->instance_prototype()));
 }
 
 
 bool TypeFeedbackOracle::LoadIsBuiltin(Property* expr, Builtins::Name id) {
-  Handle<Object> object = GetElement(map_, expr->position());
-  return *object == Builtins::builtin(id);
+  return *GetInfo(expr->position()) == Builtins::builtin(id);
 }
 
 
 TypeInfo TypeFeedbackOracle::CompareType(CompareOperation* expr) {
-  Handle<Object> object = GetElement(map_, expr->position());
+  Handle<Object> object = GetInfo(expr->position());
   TypeInfo unknown = TypeInfo::Unknown();
   if (!object->IsCode()) return unknown;
   Handle<Code> code = Handle<Code>::cast(object);
   if (!code->is_compare_ic_stub()) return unknown;
 
   CompareIC::State state = static_cast<CompareIC::State>(code->compare_state());
   switch (state) {
     case CompareIC::UNINITIALIZED:
       // Uninitialized means never executed.
       // TODO(fschneider): Introduce a separate value for never-executed ICs.
       return unknown;
     case CompareIC::SMIS:
       return TypeInfo::Smi();
     case CompareIC::HEAP_NUMBERS:
       return TypeInfo::Number();
     case CompareIC::OBJECTS:
       // TODO(kasperl): We really need a type for JS objects here.
       return TypeInfo::NonPrimitive();
     case CompareIC::GENERIC:
     default:
       return unknown;
   }
 }
 
 
 TypeInfo TypeFeedbackOracle::BinaryType(BinaryOperation* expr) {
-  Handle<Object> object = GetElement(map_, expr->position());
+  Handle<Object> object = GetInfo(expr->position());
   TypeInfo unknown = TypeInfo::Unknown();
   if (!object->IsCode()) return unknown;
   Handle<Code> code = Handle<Code>::cast(object);
   if (code->is_binary_op_stub()) {
     BinaryOpIC::TypeInfo type = static_cast<BinaryOpIC::TypeInfo>(
         code->binary_op_type());
     switch (type) {
       case BinaryOpIC::UNINIT_OR_SMI:
         return TypeInfo::Smi();
       case BinaryOpIC::DEFAULT:
@@ skipping 41 matching lines @@
         return unknown;
      default:
         return unknown;
     }
   }
   return unknown;
 }
 
 
 TypeInfo TypeFeedbackOracle::SwitchType(CaseClause* clause) {
-  Handle<Object> object = GetElement(map_, clause->position());
+  Handle<Object> object = GetInfo(clause->position());
   TypeInfo unknown = TypeInfo::Unknown();
   if (!object->IsCode()) return unknown;
   Handle<Code> code = Handle<Code>::cast(object);
   if (!code->is_compare_ic_stub()) return unknown;
 
   CompareIC::State state = static_cast<CompareIC::State>(code->compare_state());
   switch (state) {
     case CompareIC::UNINITIALIZED:
       // Uninitialized means never executed.
       // TODO(fschneider): Introduce a separate value for never-executed ICs.
       return unknown;
     case CompareIC::SMIS:
       return TypeInfo::Smi();
     case CompareIC::HEAP_NUMBERS:
       return TypeInfo::Number();
     case CompareIC::OBJECTS:
       // TODO(kasperl): We really need a type for JS objects here.
       return TypeInfo::NonPrimitive();
     case CompareIC::GENERIC:
     default:
       return unknown;
   }
 }
 
 
 ZoneMapList* TypeFeedbackOracle::CollectReceiverTypes(int position,
                                                       Handle<String> name,
                                                       Code::Flags flags) {
-  Handle<Object> object = GetElement(map_, position);
+  Handle<Object> object = GetInfo(position);
   if (object->IsUndefined() || object->IsSmi()) return NULL;
 
   if (*object == Builtins::builtin(Builtins::StoreIC_GlobalProxy)) {
     // TODO(fschneider): We could collect the maps and signal that
     // we need a generic store (or load) here.
     ASSERT(Handle<Code>::cast(object)->ic_state() == MEGAMORPHIC);
     return NULL;
   } else if (object->IsMap()) {
     ZoneMapList* types = new ZoneMapList(1);
     types->Add(Handle<Map>::cast(object));
@@ skipping 10 matching lines @@
 
 
 void TypeFeedbackOracle::PopulateMap(Handle<Code> code) {
   HandleScope scope;
 
   const int kInitialCapacity = 16;
   List<int> code_positions(kInitialCapacity);
   List<int> source_positions(kInitialCapacity);
   CollectPositions(*code, &code_positions, &source_positions);
 
+  ASSERT(dictionary_.is_null());  // Only initialize once.
+  dictionary_ = Factory::NewNumberDictionary(code_positions.length());
+
   int length = code_positions.length();
   ASSERT(source_positions.length() == length);
   for (int i = 0; i < length; i++) {
+    HandleScope loop_scope;
     RelocInfo info(code->instruction_start() + code_positions[i],
                    RelocInfo::CODE_TARGET, 0);
     Handle<Code> target(Code::GetCodeFromTargetAddress(info.target_address()));
     int position = source_positions[i];
     InlineCacheState state = target->ic_state();
     Code::Kind kind = target->kind();
+    Handle<Object> value;
     if (kind == Code::BINARY_OP_IC ||
         kind == Code::TYPE_RECORDING_BINARY_OP_IC ||
         kind == Code::COMPARE_IC) {
       // TODO(kasperl): Avoid having multiple ICs with the same
       // position by making sure that we have position information
       // recorded for all binary ICs.
-      if (GetElement(map_, position)->IsUndefined()) {
-        SetElement(map_, position, target, kNonStrictMode);
+      int entry = dictionary_->FindEntry(position);
+      if (entry == NumberDictionary::kNotFound) {
+        value = target;
       }
     } else if (state == MONOMORPHIC) {
       if (target->kind() != Code::CALL_IC ||
           target->check_type() == RECEIVER_MAP_CHECK) {
         Handle<Map> map = Handle<Map>(target->FindFirstMap());
         if (*map == NULL) {
-          SetElement(map_, position, target, kNonStrictMode);
+          value = target;
         } else {
-          SetElement(map_, position, map, kNonStrictMode);
+          value = map;
         }
       } else {
         ASSERT(target->kind() == Code::CALL_IC);
         CheckType check = target->check_type();
         ASSERT(check != RECEIVER_MAP_CHECK);
-        SetElement(map_, position,
-                   Handle<Object>(Smi::FromInt(check)), kNonStrictMode);
-        ASSERT(Smi::cast(*GetElement(map_, position))->value() == check);
+        value = Handle<Object>(Smi::FromInt(check));
       }
     } else if (state == MEGAMORPHIC) {
-      SetElement(map_, position, target, kNonStrictMode);
+      value = target;
+    }
+
+    if (!value.is_null()) {
+      Handle<NumberDictionary> new_dict =
+          Factory::DictionaryAtNumberPut(dictionary_, position, value);
+      dictionary_ = loop_scope.CloseAndEscape(new_dict);
     }
   }
+  // Allocate handle in the parent scope.
+  dictionary_ = scope.CloseAndEscape(dictionary_);
 }
 
 
 void TypeFeedbackOracle::CollectPositions(Code* code,
                                           List<int>* code_positions,
                                           List<int>* source_positions) {
   AssertNoAllocation no_allocation;
   int position = 0;
   // Because the ICs we use for global variables access in the full
   // code generator do not have any meaningful positions, we avoid
@@ skipping 25 matching lines @@
         source_positions->Add(position);
       }
     } else {
       ASSERT(RelocInfo::IsPosition(mode));
       position = static_cast<int>(info->data());
     }
   }
 }
 
 } }  // namespace v8::internal