Recover performance of array buffer view field accesses in ICs

src/accessors.cc

 // Copyright 2012 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/v8.h"
 
 #include "src/accessors.h"
 #include "src/api.h"
 #include "src/contexts.h"
 #include "src/deoptimizer.h"
@@ skipping 75 matching lines @@
       if (map->instance_type() < FIRST_NONSTRING_TYPE) {
         return CheckForName(name, isolate->factory()->length_string(),
                             String::kLengthOffset, object_offset);
       }
 
       return false;
   }
 }
 
 
+bool Accessors::IsJSArrayBufferViewFieldAccessor(Handle<Map> map,
+                                                 Handle<Name> name,
+                                                 int* object_offset) {
+  Isolate* isolate = name->GetIsolate();
+
+  switch (map->instance_type()) {
+    case JS_TYPED_ARRAY_TYPE:
+      // %TypedArray%.prototype is non-configurable, and so are the following
+      // named properties on %TypedArray%.prototype, so we can directly inline
+      // the field-load for typed array maps that still use their
+      // %TypedArray%.prototype.
+      if (JSFunction::cast(map->GetConstructor())->prototype() !=
+          map->prototype()) {
+        return false;
+      }
+      return CheckForName(name, isolate->factory()->length_string(),
+                          JSTypedArray::kLengthOffset, object_offset) ||
+             CheckForName(name, isolate->factory()->byte_length_string(),
+                          JSTypedArray::kByteLengthOffset, object_offset) ||
+             CheckForName(name, isolate->factory()->byte_offset_string(),
+                          JSTypedArray::kByteOffsetOffset, object_offset);
+
+    case JS_DATA_VIEW_TYPE:
+      return CheckForName(name, isolate->factory()->byte_length_string(),
+                          JSDataView::kByteLengthOffset, object_offset) ||
+             CheckForName(name, isolate->factory()->byte_offset_string(),
+                          JSDataView::kByteOffsetOffset, object_offset);
+    default:
+      return false;
+  }
+}
+
+
 bool SetPropertyOnInstanceIfInherited(
     Isolate* isolate, const v8::PropertyCallbackInfo<void>& info,
     v8::Local<v8::Name> name, Handle<Object> value) {
   Handle<Object> holder = Utils::OpenHandle(*info.Holder());
   Handle<Object> receiver = Utils::OpenHandle(*info.This());
   if (*holder == *receiver) return false;
   if (receiver->IsJSObject()) {
     Handle<JSObject> object = Handle<JSObject>::cast(receiver);
     // This behaves sloppy since we lost the actual strict-mode.
     // TODO(verwaest): Fix by making ExecutableAccessorInfo behave like data
@@ skipping 1348 matching lines @@
   info->set_data(Smi::FromInt(index));
   Handle<Object> getter = v8::FromCData(isolate, &ModuleGetExport);
   Handle<Object> setter = v8::FromCData(isolate, &ModuleSetExport);
   info->set_getter(*getter);
   if (!(attributes & ReadOnly)) info->set_setter(*setter);
   return info;
 }
 
 
 } }  // namespace v8::internal