Adding ElementsAccessor::Pop

src/elements.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/elements.h"
 
 #include "src/arguments.h"
 #include "src/conversions.h"
 #include "src/factory.h"
 #include "src/messages.h"
@@ skipping 621 matching lines @@
   }
 
   static Handle<JSArray> SpliceImpl(Handle<JSArray> receiver,
                                     Handle<FixedArrayBase> backing_store,
                                     uint32_t start, uint32_t delete_count,
                                     Arguments args, uint32_t add_count) {
     UNREACHABLE();
     return Handle<JSArray>();
   }
 
+  virtual Handle<Object> Pop(Handle<JSArray> receiver,
+                             Handle<FixedArrayBase> backing_store) final {
+    return ElementsAccessorSubclass::PopImpl(receiver, backing_store);
+  }
+
+  static Handle<Object> PopImpl(Handle<JSArray> receiver,
+                                Handle<FixedArrayBase> backing_store) {
+    UNREACHABLE();
+    return Handle<Object>();
+  }
 
   virtual void SetLength(Handle<JSArray> array, uint32_t length) final {
     ElementsAccessorSubclass::SetLengthImpl(array, length,
                                             handle(array->elements()));
   }
 
   static void SetLengthImpl(Handle<JSArray> array, uint32_t length,
                             Handle<FixedArrayBase> backing_store);
 
   static Handle<FixedArrayBase> ConvertElementsWithCapacity(
@@ skipping 560 matching lines @@
     if (IsFastSmiElementsKind(KindTraits::Kind)) {
       for (int i = 0; i < length; i++) {
         DCHECK(BackingStore::get(backing_store, i)->IsSmi() ||
                (IsFastHoleyElementsKind(KindTraits::Kind) &&
                 backing_store->is_the_hole(i)));
       }
     }
 #endif
   }
 
+  static Handle<Object> PopImpl(Handle<JSArray> receiver,
+                                Handle<FixedArrayBase> backing_store) {
+    uint32_t new_length =
+        static_cast<uint32_t>(Smi::cast(receiver->length())->value()) - 1;
+    Handle<Object> result =
+        FastElementsAccessorSubclass::GetImpl(backing_store, new_length);
+    FastElementsAccessorSubclass::SetLengthImpl(receiver, new_length,
+                                                backing_store);
+
+    if (IsHoleyElementsKind(KindTraits::Kind) && result->IsTheHole()) {
+      result = receiver->GetIsolate()->factory()->undefined_value();
+    }
+    return result;
+  }
+
   static uint32_t PushImpl(Handle<JSArray> receiver,
                            Handle<FixedArrayBase> backing_store,
                            Object** objects, uint32_t push_size,
                            int direction) {
     uint32_t len = Smi::cast(receiver->length())->value();
     if (push_size == 0) {
       return len;
     }
     uint32_t elms_len = backing_store->length();
     // Currently fixed arrays cannot grow too big, so
@@ skipping 964 matching lines @@
 #define ACCESSOR_DELETE(Class, Kind, Store) delete elements_accessors_[Kind];
   ELEMENTS_LIST(ACCESSOR_DELETE)
 #undef ACCESSOR_DELETE
   elements_accessors_ = NULL;
 }
 
 
 ElementsAccessor** ElementsAccessor::elements_accessors_ = NULL;
 }  // namespace internal
 }  // namespace v8