Ensure newly allocated empty Arrays are transitioned to FAST_ELEMENT

src/contexts.h

 // Copyright 2011 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 88 matching lines @@
 #define GLOBAL_CONTEXT_FIELDS(V) \
   V(GLOBAL_PROXY_INDEX, JSObject, global_proxy_object) \
   V(SECURITY_TOKEN_INDEX, Object, security_token) \
   V(BOOLEAN_FUNCTION_INDEX, JSFunction, boolean_function) \
   V(NUMBER_FUNCTION_INDEX, JSFunction, number_function) \
   V(STRING_FUNCTION_INDEX, JSFunction, string_function) \
   V(STRING_FUNCTION_PROTOTYPE_MAP_INDEX, Map, string_function_prototype_map) \
   V(OBJECT_FUNCTION_INDEX, JSFunction, object_function) \
   V(INTERNAL_ARRAY_FUNCTION_INDEX, JSFunction, internal_array_function) \
   V(ARRAY_FUNCTION_INDEX, JSFunction, array_function) \
+  V(FAST_ARRAY_ELEMENT_BIAS_INDEX, Object, fast_array_element_bias) \
+  V(UNTRANSITIONED_JS_ARRAY_MAP_INDEX, Object, untransitioned_js_array_map) \
   V(DATE_FUNCTION_INDEX, JSFunction, date_function) \
   V(JSON_OBJECT_INDEX, JSObject, json_object) \
   V(REGEXP_FUNCTION_INDEX, JSFunction, regexp_function) \
   V(INITIAL_OBJECT_PROTOTYPE_INDEX, JSObject, initial_object_prototype) \
   V(CREATE_DATE_FUN_INDEX, JSFunction,  create_date_fun) \
   V(TO_NUMBER_FUN_INDEX, JSFunction, to_number_fun) \
   V(TO_STRING_FUN_INDEX, JSFunction, to_string_fun) \
   V(TO_DETAIL_STRING_FUN_INDEX, JSFunction, to_detail_string_fun) \
   V(TO_OBJECT_FUN_INDEX, JSFunction, to_object_fun) \
   V(TO_INTEGER_FUN_INDEX, JSFunction, to_integer_fun) \
   V(TO_UINT32_FUN_INDEX, JSFunction, to_uint32_fun) \
   V(TO_INT32_FUN_INDEX, JSFunction, to_int32_fun) \
   V(GLOBAL_EVAL_FUN_INDEX, JSFunction, global_eval_fun) \
   V(INSTANTIATE_FUN_INDEX, JSFunction, instantiate_fun) \
   V(CONFIGURE_INSTANCE_FUN_INDEX, JSFunction, configure_instance_fun) \
   V(FUNCTION_MAP_INDEX, Map, function_map) \
   V(STRICT_MODE_FUNCTION_MAP_INDEX, Map, strict_mode_function_map) \
   V(FUNCTION_WITHOUT_PROTOTYPE_MAP_INDEX, Map, function_without_prototype_map) \
   V(STRICT_MODE_FUNCTION_WITHOUT_PROTOTYPE_MAP_INDEX, Map, \
     strict_mode_function_without_prototype_map) \
   V(FUNCTION_INSTANCE_MAP_INDEX, Map, function_instance_map) \
   V(STRICT_MODE_FUNCTION_INSTANCE_MAP_INDEX, Map, \
     strict_mode_function_instance_map) \
-  V(JS_ARRAY_MAP_INDEX, Map, js_array_map)\
   V(REGEXP_RESULT_MAP_INDEX, Map, regexp_result_map)\
   V(ARGUMENTS_BOILERPLATE_INDEX, JSObject, arguments_boilerplate) \
   V(ALIASED_ARGUMENTS_BOILERPLATE_INDEX, JSObject, \
     aliased_arguments_boilerplate) \
   V(STRICT_MODE_ARGUMENTS_BOILERPLATE_INDEX, JSObject, \
     strict_mode_arguments_boilerplate) \
   V(MESSAGE_LISTENERS_INDEX, JSObject, message_listeners) \
   V(MAKE_MESSAGE_FUN_INDEX, JSFunction, make_message_fun) \
   V(GET_STACK_TRACE_LINE_INDEX, JSFunction, get_stack_trace_line_fun) \
   V(CONFIGURE_GLOBAL_INDEX, JSFunction, configure_global_fun) \
@@ skipping 81 matching lines @@
 
     // This slot holds the thrown value in catch contexts.
     THROWN_OBJECT_INDEX = MIN_CONTEXT_SLOTS,
 
     // These slots are only in global contexts.
     GLOBAL_PROXY_INDEX = MIN_CONTEXT_SLOTS,
     SECURITY_TOKEN_INDEX,
     ARGUMENTS_BOILERPLATE_INDEX,
     ALIASED_ARGUMENTS_BOILERPLATE_INDEX,
     STRICT_MODE_ARGUMENTS_BOILERPLATE_INDEX,
-    JS_ARRAY_MAP_INDEX,
     REGEXP_RESULT_MAP_INDEX,
     FUNCTION_MAP_INDEX,
     STRICT_MODE_FUNCTION_MAP_INDEX,
     FUNCTION_WITHOUT_PROTOTYPE_MAP_INDEX,
     STRICT_MODE_FUNCTION_WITHOUT_PROTOTYPE_MAP_INDEX,
     FUNCTION_INSTANCE_MAP_INDEX,
     STRICT_MODE_FUNCTION_INSTANCE_MAP_INDEX,
     INITIAL_OBJECT_PROTOTYPE_INDEX,
     BOOLEAN_FUNCTION_INDEX,
     NUMBER_FUNCTION_INDEX,
     STRING_FUNCTION_INDEX,
     STRING_FUNCTION_PROTOTYPE_MAP_INDEX,
     OBJECT_FUNCTION_INDEX,
     INTERNAL_ARRAY_FUNCTION_INDEX,
     ARRAY_FUNCTION_INDEX,
+    UNTRANSITIONED_JS_ARRAY_MAP_INDEX,
+    FAST_ARRAY_ELEMENT_BIAS_INDEX,
     DATE_FUNCTION_INDEX,
     JSON_OBJECT_INDEX,
     REGEXP_FUNCTION_INDEX,
     CREATE_DATE_FUN_INDEX,
     TO_NUMBER_FUN_INDEX,
     TO_STRING_FUN_INDEX,
     TO_DETAIL_STRING_FUN_INDEX,
     TO_OBJECT_FUN_INDEX,
     TO_INTEGER_FUN_INDEX,
     TO_UINT32_FUN_INDEX,
@@ skipping 163 matching lines @@
 #ifdef DEBUG
   // Bootstrapping-aware type checks.
   static bool IsBootstrappingOrContext(Object* object);
   static bool IsBootstrappingOrGlobalObject(Object* object);
 #endif
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_CONTEXTS_H_