[stubs] Implement binary-search descriptor lookup in CSA

src/ic/accessor-assembler.cc

 // Copyright 2016 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/accessor-assembler.h"
 
 #include "src/code-factory.h"
 #include "src/code-stubs.h"
 #include "src/ic/handler-configuration.h"
 #include "src/ic/stub-cache.h"
@@ skipping 1151 matching lines @@
          slow);
 
   // Check if the receiver has fast or slow properties.
   Node* properties = LoadProperties(receiver);
   Node* properties_map = LoadMap(properties);
   GotoIf(WordEqual(properties_map, LoadRoot(Heap::kHashTableMapRootIndex)),
          &if_property_dictionary);
 
   // Try looking up the property on the receiver; if unsuccessful, look
   // for a handler in the stub cache.
-  Comment("DescriptorArray lookup");
+  Node* bitfield3 = LoadMapBitField3(receiver_map);
+  Node* descriptors = LoadMapDescriptors(receiver_map);
 
-  // Skip linear search if there are too many descriptors.
-  // TODO(jkummerow): Consider implementing binary search.
-  // See also TryLookupProperty() which has the same limitation.
-  const int32_t kMaxLinear = 210;
-  Label stub_cache(this);
-  Node* bitfield3 = LoadMapBitField3(receiver_map);
-  Node* nof = DecodeWordFromWord32<Map::NumberOfOwnDescriptorsBits>(bitfield3);
-  GotoIf(UintPtrLessThan(IntPtrConstant(kMaxLinear), nof), &stub_cache);
-  Node* descriptors = LoadMapDescriptors(receiver_map);
+  Label if_descriptor_found(this), stub_cache(this);
   Variable var_name_index(this, MachineType::PointerRepresentation());
-  Label if_descriptor_found(this);
-  DescriptorLookupLinear(key, descriptors, nof, &if_descriptor_found,
-                         &var_name_index, &stub_cache);
+  DescriptorLookup(key, descriptors, bitfield3, &if_descriptor_found,
+                   &var_name_index, &stub_cache);
 
   Bind(&if_descriptor_found);
   {
     LoadPropertyFromFastObject(receiver, receiver_map, descriptors,
                                var_name_index.value(), &var_details,
                                &var_value);
     Goto(&if_found_on_receiver);
   }
 
   Bind(&stub_cache);
@@ skipping 751 matching lines @@
   Node* slot = Parameter(Descriptor::kSlot);
   Node* context = Parameter(Descriptor::kContext);
   Node* vector = LoadFeedbackVectorForStub();
 
   StoreICParameters p(context, receiver, name, value, slot, vector);
   KeyedStoreIC(&p, language_mode);
 }
 
 }  // namespace internal
 }  // namespace v8