Move DeepCopy of JSObject from runtime to object.

src/objects.cc

Index: src/objects.cc
diff --git a/src/objects.cc b/src/objects.cc
index a3163eb619c6d76ff18ab33db93ded19414542c3..f3e7471c07b74a43421ae1c90f110d9374211ec5 100644
--- a/src/objects.cc
+++ b/src/objects.cc
@@ -4689,6 +4689,145 @@ MaybeObject* JSObject::PreventExtensions() {
 }
 
 
+MUST_USE_RESULT MaybeObject* JSObject::DeepCopy(Isolate* isolate) {
+  StackLimitCheck check(isolate);
+  if (check.HasOverflowed()) return isolate->StackOverflow();
+
+  Heap* heap = isolate->heap();
+  Object* result;
+  { MaybeObject* maybe_result = heap->CopyJSObject(this);
+    if (!maybe_result->ToObject(&result)) return maybe_result;
+  }
+  JSObject* copy = JSObject::cast(result);
+
+  // Deep copy local properties.
+  if (copy->HasFastProperties()) {
+    FixedArray* properties = copy->properties();
+    for (int i = 0; i < properties->length(); i++) {
+      Object* value = properties->get(i);
+      if (value->IsJSObject()) {
+        JSObject* js_object = JSObject::cast(value);
+        { MaybeObject* maybe_result = js_object->DeepCopy(isolate);
+          if (!maybe_result->ToObject(&result)) return maybe_result;
+        }
+        properties->set(i, result);
+      }
+    }
+    int nof = copy->map()->inobject_properties();
+    for (int i = 0; i < nof; i++) {
+      Object* value = copy->InObjectPropertyAt(i);
+      if (value->IsJSObject()) {
+        JSObject* js_object = JSObject::cast(value);
+        { MaybeObject* maybe_result = js_object->DeepCopy(isolate);
+          if (!maybe_result->ToObject(&result)) return maybe_result;
+        }
+        copy->InObjectPropertyAtPut(i, result);
+      }
+    }
+  } else {
+    { MaybeObject* maybe_result =
+          heap->AllocateFixedArray(copy->NumberOfLocalProperties());
+      if (!maybe_result->ToObject(&result)) return maybe_result;
+    }
+    FixedArray* names = FixedArray::cast(result);
+    copy->GetLocalPropertyNames(names, 0);
+    for (int i = 0; i < names->length(); i++) {
+      ASSERT(names->get(i)->IsString());
+      String* key_string = String::cast(names->get(i));
+      PropertyAttributes attributes =
+          copy->GetLocalPropertyAttribute(key_string);
+      // Only deep copy fields from the object literal expression.
+      // In particular, don't try to copy the length attribute of
+      // an array.
+      if (attributes != NONE) continue;
+      Object* value =
+          copy->GetProperty(key_string, &attributes)->ToObjectUnchecked();
+      if (value->IsJSObject()) {
+        JSObject* js_object = JSObject::cast(value);
+        { MaybeObject* maybe_result = js_object->DeepCopy(isolate);
+          if (!maybe_result->ToObject(&result)) return maybe_result;
+        }
+        { MaybeObject* maybe_result =
+              // Creating object copy for literals. No strict mode needed.
+              copy->SetProperty(key_string, result, NONE, kNonStrictMode);
+          if (!maybe_result->ToObject(&result)) return maybe_result;
+        }
+      }
+    }
+  }
+
+  // Deep copy local elements.
+  // Pixel elements cannot be created using an object literal.
+  ASSERT(!copy->HasExternalArrayElements());
+  switch (copy->GetElementsKind()) {
+    case FAST_SMI_ELEMENTS:
+    case FAST_ELEMENTS:
+    case FAST_HOLEY_SMI_ELEMENTS:
+    case FAST_HOLEY_ELEMENTS: {
+      FixedArray* elements = FixedArray::cast(copy->elements());
+      if (elements->map() == heap->fixed_cow_array_map()) {
+        isolate->counters()->cow_arrays_created_runtime()->Increment();
+#ifdef DEBUG
+        for (int i = 0; i < elements->length(); i++) {
+          ASSERT(!elements->get(i)->IsJSObject());
+        }
+#endif
+      } else {
+        for (int i = 0; i < elements->length(); i++) {
+          Object* value = elements->get(i);
+          ASSERT(value->IsSmi() ||
+                 value->IsTheHole() ||
+                 (IsFastObjectElementsKind(copy->GetElementsKind())));
+          if (value->IsJSObject()) {
+            JSObject* js_object = JSObject::cast(value);
+            { MaybeObject* maybe_result = js_object->DeepCopy(isolate);
+              if (!maybe_result->ToObject(&result)) return maybe_result;
+            }
+            elements->set(i, result);
+          }
+        }
+      }
+      break;
+    }
+    case DICTIONARY_ELEMENTS: {
+      SeededNumberDictionary* element_dictionary = copy->element_dictionary();
+      int capacity = element_dictionary->Capacity();
+      for (int i = 0; i < capacity; i++) {
+        Object* k = element_dictionary->KeyAt(i);
+        if (element_dictionary->IsKey(k)) {
+          Object* value = element_dictionary->ValueAt(i);
+          if (value->IsJSObject()) {
+            JSObject* js_object = JSObject::cast(value);
+            { MaybeObject* maybe_result = js_object->DeepCopy(isolate);
+              if (!maybe_result->ToObject(&result)) return maybe_result;
+            }
+            element_dictionary->ValueAtPut(i, result);
+          }
+        }
+      }
+      break;
+    }
+    case NON_STRICT_ARGUMENTS_ELEMENTS:
+      UNIMPLEMENTED();
+      break;
+    case EXTERNAL_PIXEL_ELEMENTS:
+    case EXTERNAL_BYTE_ELEMENTS:
+    case EXTERNAL_UNSIGNED_BYTE_ELEMENTS:
+    case EXTERNAL_SHORT_ELEMENTS:
+    case EXTERNAL_UNSIGNED_SHORT_ELEMENTS:
+    case EXTERNAL_INT_ELEMENTS:
+    case EXTERNAL_UNSIGNED_INT_ELEMENTS:
+    case EXTERNAL_FLOAT_ELEMENTS:
+    case EXTERNAL_DOUBLE_ELEMENTS:
+    case FAST_DOUBLE_ELEMENTS:
+    case FAST_HOLEY_DOUBLE_ELEMENTS:
+      // No contained objects, nothing to do.
+      break;
+  }
+  return copy;
+}
+
+
 // Tests for the fast common case for property enumeration:
 // - This object and all prototypes has an enum cache (which means that
 //   it is no proxy, has no interceptors and needs no access checks).