Use virtual method return type covariance in clone()

Let clone() return pointer to the actual type instead of returning
pointer to generic ObjectData. Avoids unnecessary static casts.

hphp/runtime/ext/ext_closure.cpp

@@ -70,13 +70,12 @@ c_Closure* c_Closure::init(int numArgs, ActRec* ar, TypedValue* sp) {
   return this;
 }
 
-ObjectData* c_Closure::clone() {
-  ObjectData* obj = ObjectData::clone();
-  auto closure = static_cast<c_Closure*>(obj);
+c_Closure* c_Closure::clone() {
+  auto closure = static_cast<c_Closure*>(ObjectData::clone());
   closure->m_VMStatics = m_VMStatics;
   closure->m_thisOrClass = m_thisOrClass;
   closure->m_func = m_func;
-  return obj;
+  return closure;
 }
 
 

hphp/runtime/ext/ext_closure.h

@@ -43,7 +43,7 @@ class c_Closure : public ExtObjectData {
   // implemented by HPHP
   public: c_Closure *create();
 public:
-  public: ObjectData* clone();
+  public: c_Closure* clone();
 
   c_Closure* init(int numArgs, ActRec* ar, TypedValue* sp);
   ObjectData* getThisOrClass() { return m_thisOrClass; }

hphp/runtime/ext/ext_collections.cpp

@@ -188,9 +188,8 @@ Array c_Vector::o_toArray() const {
   return toArrayImpl();
 }
 
-ObjectData* c_Vector::clone() {
-  ObjectData* obj = ObjectData::clone();
-  auto target = static_cast<c_Vector*>(obj);
+c_Vector* c_Vector::clone() {
+  auto target = static_cast<c_Vector*>(ObjectData::clone());
   uint sz = m_size;
   TypedValue* data;
   target->m_capacity = target->m_size = sz;
@@ -198,7 +197,7 @@ ObjectData* c_Vector::clone() {
   for (int i = 0; i < sz; ++i) {
     tvDup(&m_data[i], &data[i]);
   }
-  return obj;
+  return target;
 }
 
 Object c_Vector::t_add(CVarRef val) {
@@ -1065,11 +1064,10 @@ Array c_Map::o_toArray() const {
   return toArrayImpl();
 }
 
-ObjectData* c_Map::clone() {
-  ObjectData* obj = ObjectData::clone();
-  auto target = static_cast<c_Map*>(obj);
+c_Map* c_Map::clone() {
+  auto target = static_cast<c_Map*>(ObjectData::clone());
 
-  if (!m_size) return obj;
+  if (!m_size) return target;
 
   assert(m_nLastSlot != 0);
   target->m_size = m_size;
@@ -1088,7 +1086,7 @@ ObjectData* c_Map::clone() {
     }
   }
 
-  return obj;
+  return target;
 }
 
 Object c_Map::t_add(CVarRef val) {
@@ -1403,7 +1401,7 @@ Object c_Map::t_differencebykey(CVarRef it) {
   }
   ObjectData* obj = it.getObjectData();
   c_Map* target;
-  Object ret = target = static_cast<c_Map*>(clone());
+  Object ret = target = clone();
   if (obj->getCollectionType() == Collection::MapType) {
     auto mp = static_cast<c_Map*>(obj);
     for (uint i = 0; i <= mp->m_nLastSlot; ++i) {
@@ -2236,11 +2234,10 @@ Array c_StableMap::o_toArray() const {
   return toArrayImpl();
 }
 
-ObjectData* c_StableMap::clone() {
-  ObjectData* obj = ObjectData::clone();
-  auto target = static_cast<c_StableMap*>(obj);
+c_StableMap* c_StableMap::clone() {
+  auto target = static_cast<c_StableMap*>(ObjectData::clone());
 
-  if (!m_size) return obj;
+  if (!m_size) return target;
 
   target->m_size = m_size;
   target->m_nTableSize = m_nTableSize;
@@ -2273,7 +2270,7 @@ ObjectData* c_StableMap::clone() {
   }
   target->m_pListTail = last;
 
-  return obj;
+  return target;
 }
 
 Object c_StableMap::t_add(CVarRef val) {
@@ -2583,7 +2580,7 @@ Object c_StableMap::t_differencebykey(CVarRef it) {
   }
   ObjectData* obj = it.getObjectData();
   c_StableMap* target;
-  Object ret = target = static_cast<c_StableMap*>(clone());
+  Object ret = target = clone();
   if (obj->getCollectionType() == Collection::StableMapType) {
     auto smp = static_cast<c_StableMap*>(obj);
     c_StableMap::Bucket* p = smp->m_pListHead;
@@ -3493,11 +3490,10 @@ Array c_Set::o_toArray() const {
   return toArrayImpl();
 }
 
-ObjectData* c_Set::clone() {
-  ObjectData* obj = ObjectData::clone();
-  auto target = static_cast<c_Set*>(obj);
+c_Set* c_Set::clone() {
+  auto target = static_cast<c_Set*>(ObjectData::clone());
 
-  if (!m_size) return obj;
+  if (!m_size) return target;
 
   assert(m_nLastSlot != 0);
   target->m_size = m_size;
@@ -3513,7 +3509,7 @@ ObjectData* c_Set::clone() {
     }
   }
 
-  return obj;
+  return target;
 }
 
 Object c_Set::t_add(CVarRef val) {
@@ -4256,7 +4252,7 @@ Array c_Pair::o_toArray() const {
   return toArrayImpl();
 }
 
-ObjectData* c_Pair::clone() {
+c_Pair* c_Pair::clone() {
   auto pair = NEWOBJ(c_Pair)();
   pair->incRefCount();
   pair->m_size = 2;
@@ -4678,7 +4674,7 @@ ArrayData* collectionDeepCopyArray(ArrayData* arr) {
 }
 
 ObjectData* collectionDeepCopyVector(c_Vector* vec) {
-  Object o = vec = static_cast<c_Vector*>(vec->clone());
+  Object o = vec = vec->clone();
   size_t sz = vec->m_size;
   for (size_t i = 0; i < sz; ++i) {
     collectionDeepCopyTV(&vec->m_data[i]);
@@ -4687,7 +4683,7 @@ ObjectData* collectionDeepCopyVector(c_Vector* vec) {
 }
 
 ObjectData* collectionDeepCopyMap(c_Map* mp) {
-  Object o = mp = static_cast<c_Map*>(mp->clone());
+  Object o = mp = mp->clone();
   uint lastSlot = mp->m_nLastSlot;
   for (uint i = 0; i <= lastSlot; ++i) {
     c_Map::Bucket* p = mp->fetchBucket(i);
@@ -4699,7 +4695,7 @@ ObjectData* collectionDeepCopyMap(c_Map* mp) {
 }
 
 ObjectData* collectionDeepCopyStableMap(c_StableMap* smp) {
-  Object o = smp = static_cast<c_StableMap*>(smp->clone());
+  Object o = smp = smp->clone();
   for (c_StableMap::Bucket* p = smp->m_pListHead; p; p = p->pListNext) {
     collectionDeepCopyTV(&p->data);
   }
@@ -4707,12 +4703,12 @@ ObjectData* collectionDeepCopyStableMap(c_StableMap* smp) {
 }
 
 ObjectData* collectionDeepCopySet(c_Set* st) {
-  Object o = st = static_cast<c_Set*>(st->clone());
+  Object o = st = st->clone();
   return o.detach();
 }
 
 ObjectData* collectionDeepCopyPair(c_Pair* pair) {
-  Object o = pair = static_cast<c_Pair*>(pair->clone());
+  Object o = pair = pair->clone();
   collectionDeepCopyTV(&pair->elm0);
   collectionDeepCopyTV(&pair->elm1);
   return o.detach();

hphp/runtime/ext/ext_collections.h

@@ -142,7 +142,7 @@ class c_Vector : public ExtObjectDataFlags<ObjectData::VectorAttrInit|
   Array toArrayImpl() const;
 
   Array o_toArray() const;
-  ObjectData* clone();
+  c_Vector* clone();
 
   enum SortFlavor { IntegerSort, StringSort, GenericSort };
 
@@ -324,7 +324,7 @@ class c_Map : public ExtObjectDataFlags<ObjectData::MapAttrInit|
   Array toArrayImpl() const;
 
   Array o_toArray() const;
-  ObjectData* clone();
+  c_Map* clone();
 
   static TypedValue* OffsetGet(ObjectData* obj, TypedValue* key);
   static void OffsetSet(ObjectData* obj, TypedValue* key, TypedValue* val);
@@ -623,7 +623,7 @@ class c_StableMap : public ExtObjectDataFlags<ObjectData::StableMapAttrInit|
   Array toArrayImpl() const;
 
   Array o_toArray() const;
-  ObjectData* clone();
+  c_StableMap* clone();
 
   static TypedValue* OffsetGet(ObjectData* obj, TypedValue* key);
   static void OffsetSet(ObjectData* obj, TypedValue* key, TypedValue* val);
@@ -849,7 +849,7 @@ class c_Set : public ExtObjectDataFlags<ObjectData::SetAttrInit|
   Array toArrayImpl() const;
 
   Array o_toArray() const;
-  ObjectData* clone();
+  c_Set* clone();
 
   static TypedValue* OffsetGet(ObjectData* obj, TypedValue* key);
   static void OffsetSet(ObjectData* obj, TypedValue* key, TypedValue* val);
@@ -1076,7 +1076,7 @@ class c_Pair : public ExtObjectDataFlags<ObjectData::PairAttrInit|
   Array toArrayImpl() const;
 
   Array o_toArray() const;
-  ObjectData* clone();
+  c_Pair* clone();
 
   static TypedValue* OffsetGet(ObjectData* obj, TypedValue* key);
   static void OffsetSet(ObjectData* obj, TypedValue* key, TypedValue* val);

hphp/runtime/ext/ext_datetime.cpp

@@ -159,11 +159,10 @@ Object c_DateTime::t_sub(CObjRef interval) {
   return this;
 }
 
-ObjectData *c_DateTime::clone() {
-  ObjectData *obj = ObjectData::clone();
-  c_DateTime *dt = static_cast<c_DateTime*>(obj);
+c_DateTime* c_DateTime::clone() {
+  c_DateTime* dt = static_cast<c_DateTime*>(ObjectData::clone());
   dt->m_dt = m_dt->cloneDateTime();
-  return obj;
+  return dt;
 }
 
 c_DateTimeZone::c_DateTimeZone(Class* cb) :
@@ -209,11 +208,10 @@ Array c_DateTimeZone::ti_listidentifiers() {
   return TimeZone::GetNames();
 }
 
-ObjectData *c_DateTimeZone::clone() {
-  ObjectData *obj = ObjectData::clone();
-  c_DateTimeZone *dtz = static_cast<c_DateTimeZone*>(obj);
+c_DateTimeZone* c_DateTimeZone::clone() {
+  c_DateTimeZone* dtz = static_cast<c_DateTimeZone*>(ObjectData::clone());
   dtz->m_tz = m_tz->cloneTimeZone();
-  return obj;
+  return dtz;
 }
 
 c_DateInterval::c_DateInterval(Class* cb) :
@@ -316,11 +314,10 @@ String c_DateInterval::t_format(CStrRef format) {
   return m_di->format(format);
 }
 
-ObjectData *c_DateInterval::clone() {
-  ObjectData *obj = ObjectData::clone();
-  c_DateInterval *di = static_cast<c_DateInterval*>(obj);
+c_DateInterval* c_DateInterval::clone() {
+  c_DateInterval *di = static_cast<c_DateInterval*>(ObjectData::clone());
   di->m_di = m_di->cloneDateInterval();
-  return obj;
+  return di;
 }
 
 ///////////////////////////////////////////////////////////////////////////////

hphp/runtime/ext/ext_datetime.h

@@ -85,7 +85,7 @@ class c_DateTime : public ExtObjectData {
  private:
   SmartObject<DateTime> m_dt;
  public:
-  virtual ObjectData *clone();
+  virtual c_DateTime* clone();
 };
 
 ///////////////////////////////////////////////////////////////////////////////
@@ -141,7 +141,7 @@ class c_DateTimeZone : public ExtObjectData {
  private:
   SmartObject<TimeZone> m_tz;
  public:
-  virtual ObjectData *clone();
+  virtual c_DateTimeZone* clone();
 };
 
 ///////////////////////////////////////////////////////////////////////////////
@@ -180,7 +180,7 @@ class c_DateInterval : public ExtObjectDataFlags<ObjectData::UseGet|ObjectData::
  private:
   SmartObject<DateInterval> m_di;
  public:
-  virtual ObjectData *clone();
+  virtual c_DateInterval* clone();
 
 };
 

hphp/runtime/ext/ext_domdocument.cpp

@@ -2002,12 +2002,11 @@ Variant c_DOMNode::t_appendchild(CObjRef newnode) {
   return create_node_object(new_child, doc(), false);
 }
 
-ObjectData *c_DOMNode::clone() {
-  ObjectData *obj = ObjectData::clone();
-  c_DOMNode *node = static_cast<c_DOMNode*>(obj);
+c_DOMNode* c_DOMNode::clone() {
+  c_DOMNode* node = static_cast<c_DOMNode*>(ObjectData::clone());
   node->m_node = m_node;
   node->m_doc = doc();
-  return obj;
+  return node;
 }
 
 Variant c_DOMNode::t_clonenode(bool deep /* = false */) {

hphp/runtime/ext/ext_domdocument.h

@@ -135,7 +135,7 @@ class c_DOMNode : public ExtObjectDataFlags<ObjectData::UseGet|ObjectData::UseSe
 
 
 public:
-  virtual ObjectData *clone();
+  virtual c_DOMNode* clone();
   virtual p_DOMDocument doc() { return m_doc;}
   p_DOMDocument m_doc;
   xmlNodePtr m_node;