Use COW to prevent unnecessary duplication of dynamic propertyes of stdClass (and other classes without predefined properties).

4 files changed, 78 insertions, 19 deletions

diff --git a/Zend/zend_builtin_functions.c b/Zend/zend_builtin_functions.c
index 8989e93fa6..8ea758adcc 100644
--- a/Zend/zend_builtin_functions.c
+++ b/Zend/zend_builtin_functions.c
@@ -1151,6 +1151,12 @@ ZEND_FUNCTION(get_object_vars)
 
 	if (!zobj->ce->default_properties_count && properties == zobj->properties) {
 		/* fast copy */
+		if (EXPECTED(zobj->handlers == &std_object_handlers)) {
+			if (EXPECTED(!(GC_FLAGS(properties) & IS_ARRAY_IMMUTABLE))) {
+				GC_REFCOUNT(properties)++;
+			}
+			RETURN_ARR(properties);
+		}
 		RETURN_ARR(zend_array_dup(properties));
 	} else {
 		array_init_size(return_value, zend_hash_num_elements(properties));
diff --git a/Zend/zend_object_handlers.c b/Zend/zend_object_handlers.c
index 74ae382df4..f284ca4b31 100644
--- a/Zend/zend_object_handlers.c
+++ b/Zend/zend_object_handlers.c
@@ -628,6 +628,12 @@ ZEND_API void zend_std_write_property(zval *object, zval *member, zval *value, v
 				goto found;
 			}
 		} else if (EXPECTED(zobj->properties != NULL)) {
+			if (UNEXPECTED(GC_REFCOUNT(zobj->properties) > 1)) {
+				if (EXPECTED(!(GC_FLAGS(zobj->properties) & IS_ARRAY_IMMUTABLE))) {
+					GC_REFCOUNT(zobj->properties)--;
+				}
+				zobj->properties = zend_array_dup(zobj->properties);
+			}
 			if ((variable_ptr = zend_hash_find(zobj->properties, Z_STR_P(member))) != NULL) {
 found:
 				zend_assign_to_variable(variable_ptr, value, IS_CV);
@@ -815,20 +821,31 @@ static zval *zend_std_get_property_ptr_ptr(zval *object, zval *member, int type,
 				}
 			}
 		} else {
-			if (UNEXPECTED(!zobj->properties) ||
-			    UNEXPECTED((retval = zend_hash_find(zobj->properties, name)) == NULL)) {
-				if (EXPECTED(!zobj->ce->__get) ||
-				    UNEXPECTED((*zend_get_property_guard(zobj, name)) & IN_GET)) {
-					if (UNEXPECTED(!zobj->properties)) {
-						rebuild_object_properties(zobj);
+			if (EXPECTED(zobj->properties)) {
+				if (UNEXPECTED(GC_REFCOUNT(zobj->properties) > 1)) {
+					if (EXPECTED(!(GC_FLAGS(zobj->properties) & IS_ARRAY_IMMUTABLE))) {
+						GC_REFCOUNT(zobj->properties)--;
 					}
-					retval = zend_hash_update(zobj->properties, name, &EG(uninitialized_zval));
-					/* Notice is thrown after creation of the property, to avoid EG(std_property_info)
-					 * being overwritten in an error handler. */
-					if (UNEXPECTED(type == BP_VAR_RW || type == BP_VAR_R)) {
-						zend_error(E_NOTICE, "Undefined property: %s::$%s", zobj->ce->name->val, name->val);
+					zobj->properties = zend_array_dup(zobj->properties);
+				}
+			    if (EXPECTED((retval = zend_hash_find(zobj->properties, name)) != NULL)) {
+					if (UNEXPECTED(Z_TYPE_P(member) != IS_STRING)) {
+						zend_string_release(name);
 					}
-	        	}
+					return retval;
+			    }
+			}
+			if (EXPECTED(!zobj->ce->__get) ||
+			    UNEXPECTED((*zend_get_property_guard(zobj, name)) & IN_GET)) {
+				if (UNEXPECTED(!zobj->properties)) {
+					rebuild_object_properties(zobj);
+				}
+				retval = zend_hash_update(zobj->properties, name, &EG(uninitialized_zval));
+				/* Notice is thrown after creation of the property, to avoid EG(std_property_info)
+				 * being overwritten in an error handler. */
+				if (UNEXPECTED(type == BP_VAR_RW || type == BP_VAR_R)) {
+					zend_error(E_NOTICE, "Undefined property: %s::$%s", zobj->ce->name->val, name->val);
+				}
 			}
 		}
 	}
@@ -866,9 +883,16 @@ static void zend_std_unset_property(zval *object, zval *member, void **cache_slo
 				ZVAL_UNDEF(slot);
 				goto exit;
 			}
-		} else if (EXPECTED(zobj->properties != NULL) &&
-        	EXPECTED(zend_hash_del(zobj->properties, Z_STR_P(member)) != FAILURE)) {
-			goto exit;
+		} else if (EXPECTED(zobj->properties != NULL)) {
+			if (UNEXPECTED(GC_REFCOUNT(zobj->properties) > 1)) {
+				if (EXPECTED(!(GC_FLAGS(zobj->properties) & IS_ARRAY_IMMUTABLE))) {
+					GC_REFCOUNT(zobj->properties)--;
+				}
+				zobj->properties = zend_array_dup(zobj->properties);
+			}
+			if (EXPECTED(zend_hash_del(zobj->properties, Z_STR_P(member)) != FAILURE)) {
+				goto exit;
+			}
 		}
 	} else if (UNEXPECTED(EG(exception))) {
 		goto exit;
diff --git a/Zend/zend_objects.c b/Zend/zend_objects.c
index 9007661f03..2a0655b258 100644
--- a/Zend/zend_objects.c
+++ b/Zend/zend_objects.c
@@ -55,7 +55,11 @@ ZEND_API void zend_object_std_dtor(zend_object *object)
 	zval *p, *end;
 
 	if (object->properties) {
-		zend_array_destroy(object->properties);
+		if (EXPECTED(!(GC_FLAGS(object->properties) & IS_ARRAY_IMMUTABLE))) {
+			if (EXPECTED(--GC_REFCOUNT(object->properties) == 0)) {
+				zend_array_destroy(object->properties);
+			}
+		}
 	}
 	p = object->properties_table;
 	if (EXPECTED(object->ce->default_properties_count)) {
@@ -163,7 +167,17 @@ ZEND_API void zend_objects_clone_members(zend_object *new_object, zend_object *o
 			src++;
 			dst++;
 		} while (src != end);
+	} else if (old_object->properties && !old_object->ce->clone) {
+		/* fast copy */
+		if (EXPECTED(old_object->handlers == &std_object_handlers)) {
+			if (EXPECTED(!(GC_FLAGS(old_object->properties) & IS_ARRAY_IMMUTABLE))) {
+				GC_REFCOUNT(old_object->properties)++;
+			}
+			new_object->properties = old_object->properties;
+			return;
+		}
 	}
+
 	if (old_object->properties &&
 	    EXPECTED(zend_hash_num_elements(old_object->properties))) {
 		zval *prop, new_prop;
diff --git a/Zend/zend_operators.c b/Zend/zend_operators.c
index d7d2591382..7e3b458bbe 100644
--- a/Zend/zend_operators.c
+++ b/Zend/zend_operators.c
@@ -588,9 +588,24 @@ try_again:
 					HashTable *obj_ht = Z_OBJ_HT_P(op)->get_properties(op);
 					if (obj_ht) {
 						zval arr;
-						ZVAL_ARR(&arr, zend_array_dup(obj_ht));
-						zval_dtor(op);
-						ZVAL_COPY_VALUE(op, &arr);
+
+						if (!Z_OBJCE_P(op)->default_properties_count && obj_ht == Z_OBJ_P(op)->properties) {
+							/* fast copy */
+							if (EXPECTED(Z_OBJ_P(op)->handlers == &std_object_handlers)) {
+								ZVAL_ARR(&arr, obj_ht);
+								if (EXPECTED(!(GC_FLAGS(Z_OBJ_P(op)->properties) & IS_ARRAY_IMMUTABLE))) {
+									GC_REFCOUNT(Z_OBJ_P(op)->properties)++;
+								}
+							} else {
+								ZVAL_ARR(&arr, zend_array_dup(obj_ht));
+							}
+							zval_dtor(op);
+							ZVAL_COPY_VALUE(op, &arr);
+						} else {
+							ZVAL_ARR(&arr, zend_array_dup(obj_ht));
+							zval_dtor(op);
+							ZVAL_COPY_VALUE(op, &arr);
+						}
 						return;
 					}
 				} else {