[KeyedLoadIC] Support Smi "handlers" for element loads

src/ic/handler-compiler.cc

 // Copyright 2014 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 "src/ic/handler-compiler.h"
 
 #include "src/field-type.h"
 #include "src/ic/call-optimization.h"
 #include "src/ic/ic-inl.h"
 #include "src/ic/ic.h"
@@ skipping 559 matching lines @@
   GenerateApiAccessorCall(masm(), call_optimization, handle(object->map()),
                           receiver(), scratch2(), true, value(), holder,
                           accessor_index);
   return GetCode(kind(), name);
 }
 
 
 #undef __
 
 // static
-Handle<Code> ElementHandlerCompiler::GetKeyedLoadHandler(
+Handle<Object> ElementHandlerCompiler::GetKeyedLoadHandler(
     Handle<Map> receiver_map, Isolate* isolate) {
   if (receiver_map->has_indexed_interceptor() &&
       !receiver_map->GetIndexedInterceptor()->getter()->IsUndefined(isolate) &&
       !receiver_map->GetIndexedInterceptor()->non_masking()) {
     TRACE_HANDLER_STATS(isolate, KeyedLoadIC_LoadIndexedInterceptorStub);
     return LoadIndexedInterceptorStub(isolate).GetCode();
   }
   if (receiver_map->IsStringMap()) {
     TRACE_HANDLER_STATS(isolate, KeyedLoadIC_LoadIndexedStringStub);
     return LoadIndexedStringStub(isolate).GetCode();
@@ skipping 12 matching lines @@
   if (elements_kind == DICTIONARY_ELEMENTS) {
     TRACE_HANDLER_STATS(isolate, KeyedLoadIC_LoadDictionaryElementStub);
     return LoadDictionaryElementStub(isolate).GetCode();
   }
   DCHECK(IsFastElementsKind(elements_kind) ||
          IsFixedTypedArrayElementsKind(elements_kind));
   bool is_js_array = instance_type == JS_ARRAY_TYPE;
   bool convert_hole_to_undefined =
       is_js_array && elements_kind == FAST_HOLEY_ELEMENTS &&
       *receiver_map == isolate->get_initial_js_array_map(elements_kind);
-  TRACE_HANDLER_STATS(isolate, KeyedLoadIC_LoadFastElementStub);
-  return LoadFastElementStub(isolate, is_js_array, elements_kind,
-                             convert_hole_to_undefined)
-      .GetCode();
+  if (FLAG_tf_load_ic_stub) {
+    int config = KeyedLoadElementsKind::encode(elements_kind) |
+                 KeyedLoadConvertHole::encode(convert_hole_to_undefined) |
+                 KeyedLoadIsJsarray::encode(is_js_array) |
+                 0;  // Element marker (as opposed to property).
+    return handle(Smi::FromInt(config), isolate);
+  } else {
+    TRACE_HANDLER_STATS(isolate, KeyedLoadIC_LoadFastElementStub);
+    return LoadFastElementStub(isolate, is_js_array, elements_kind,
+                               convert_hole_to_undefined)
+        .GetCode();
+  }
 }
 
 void ElementHandlerCompiler::CompileElementHandlers(
     MapHandleList* receiver_maps, List<Handle<Object>>* handlers) {
   for (int i = 0; i < receiver_maps->length(); ++i) {
     handlers->Add(GetKeyedLoadHandler(receiver_maps->at(i), isolate()));
   }
 }
 }  // namespace internal
 }  // namespace v8