Fix speedup of typedarray-length loading in the ICs as well as Crankshaft

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 61 matching lines @@
 bool Accessors::IsJSObjectFieldAccessor(Handle<Map> map, Handle<Name> name,
                                         int* object_offset) {
   Isolate* isolate = name->GetIsolate();
 
   switch (map->instance_type()) {
     case JS_ARRAY_TYPE:
       return
         CheckForName(name, isolate->factory()->length_string(),
                      JSArray::kLengthOffset, object_offset);
     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_ARRAY_BUFFER_TYPE:
       return
         CheckForName(name, isolate->factory()->byte_length_string(),
@@ skipping 1468 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