ExtendStorageStub added, it is aimed for extending objects backing store when it runs out of space.

src/code-stubs.h

 // 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.
 
 #ifndef V8_CODE_STUBS_H_
 #define V8_CODE_STUBS_H_
 
 #include "src/allocation.h"
 #include "src/assembler.h"
 #include "src/codegen.h"
@@ skipping 65 matching lines @@
   V(StringAdd)                              \
   V(ToBoolean)                              \
   V(ToNumber)                               \
   V(TransitionElementsKind)                 \
   V(VectorKeyedLoad)                        \
   V(VectorLoad)                             \
   /* IC Handler stubs */                    \
   V(LoadConstant)                           \
   V(LoadField)                              \
   V(StoreField)                             \
+  V(ExtendStorage)                          \
   V(StoreGlobal)                            \
   V(StringLength)
 
 // List of code stubs only used on ARM 32 bits platforms.
 #if V8_TARGET_ARCH_ARM
 #define CODE_STUB_LIST_ARM(V) \
   V(DirectCEntry)             \
   V(WriteInt32ToHeapNumber)
 
 #else
@@ skipping 878 matching lines @@
   virtual Code::StubType GetStubType() { return Code::FAST; }
 
  private:
   class StoreFieldByIndexBits : public BitField<int, 0, 13> {};
   class RepresentationBits : public BitField<uint8_t, 13, 4> {};
 
   DEFINE_HANDLER_CODE_STUB(StoreField, HandlerStub);
 };
 
 
+// Extend storage is called in a store inline cache when
+// it is necessary to extend the properties array of a
+// JSObject.
+class ExtendStorageStub : public HandlerStub {
+ public:
+  ExtendStorageStub(Isolate* isolate, FieldIndex index,
+                    Representation representation)
+      : HandlerStub(isolate) {
+    int property_index_key = index.GetFieldAccessStubKey();
+    uint8_t repr = PropertyDetails::EncodeRepresentation(representation);
+    set_sub_minor_key(StoreFieldByIndexBits::encode(property_index_key) |
+                      RepresentationBits::encode(repr));
+  }
+
+  FieldIndex index() const {
+    int property_index_key = StoreFieldByIndexBits::decode(sub_minor_key());
+    return FieldIndex::FromFieldAccessStubKey(property_index_key);
+  }
+
+  Representation representation() {
+    uint8_t repr = RepresentationBits::decode(sub_minor_key());
+    return PropertyDetails::DecodeRepresentation(repr);
+  }
+
+ protected:
+  virtual Code::Kind kind() const { return Code::STORE_IC; }
+  virtual Code::StubType GetStubType() { return Code::FAST; }
+
+ private:
+  class StoreFieldByIndexBits : public BitField<int, 0, 13> {};
+  class RepresentationBits : public BitField<uint8_t, 13, 4> {};
+
+  DEFINE_HANDLER_CODE_STUB(ExtendStorage, HandlerStub);
+};
+
+
 class StoreGlobalStub : public HandlerStub {
  public:
   StoreGlobalStub(Isolate* isolate, bool is_constant, bool check_global)
       : HandlerStub(isolate) {
     set_sub_minor_key(IsConstantBits::encode(is_constant) |
                       CheckGlobalBits::encode(check_global));
   }
 
   static Handle<HeapObject> global_placeholder(Isolate* isolate) {
     return isolate->factory()->uninitialized_value();
@@ skipping 1419 matching lines @@
 
 #undef DEFINE_CALL_INTERFACE_DESCRIPTOR
 #undef DEFINE_PLATFORM_CODE_STUB
 #undef DEFINE_HANDLER_CODE_STUB
 #undef DEFINE_HYDROGEN_CODE_STUB
 #undef DEFINE_CODE_STUB
 #undef DEFINE_CODE_STUB_BASE
 } }  // namespace v8::internal
 
 #endif  // V8_CODE_STUBS_H_