Avoid refcounted copy in _object_properties_init() for internal classes (#12474)

This currently uses ZVAL_COPY_OR_DUP, which copies the value and handles
refcounting. However, internal classes cannot have refcounted default
properties because of constraints imposed by
zend_declare_typed_property(). So copying the value is sufficient.

While this doesn't really improve the performance for our benchmarks, it
improves performance for cases where a lot of temporary internal objects
are instantiated. For example, when instantiating DOM classes: DOM
objects are transient, so lots of temporary objects are created.

Author: nielsdos

Zend/zend_API.c

@@ -1610,8 +1610,11 @@ static zend_always_inline void _object_properties_init(zend_object *object, zend
 		zval *end = src + class_type->default_properties_count;
 
 		if (UNEXPECTED(class_type->type == ZEND_INTERNAL_CLASS)) {
+			/* We don't have to account for refcounting because
+			 * zend_declare_typed_property() disallows refcounted defaults for internal classes. */
 			do {
-				ZVAL_COPY_OR_DUP_PROP(dst, src);
+				ZEND_ASSERT(!Z_REFCOUNTED_P(src));
+				ZVAL_COPY_VALUE_PROP(dst, src);
 				src++;
 				dst++;
 			} while (src != end);

Zend/zend_inheritance.c

@@ -1547,7 +1547,10 @@ ZEND_API void zend_do_inheritance_ex(zend_class_entry *ce, zend_class_entry *par
 			do {
 				dst--;
 				src--;
-				ZVAL_COPY_OR_DUP_PROP(dst, src);
+				/* We don't have to account for refcounting because
+				 * zend_declare_typed_property() disallows refcounted defaults for internal classes. */
+				ZEND_ASSERT(!Z_REFCOUNTED_P(src));
+				ZVAL_COPY_VALUE_PROP(dst, src);
 				if (Z_OPT_TYPE_P(dst) == IS_CONSTANT_AST) {
 					ce->ce_flags &= ~ZEND_ACC_CONSTANTS_UPDATED;
 					ce->ce_flags |= ZEND_ACC_HAS_AST_PROPERTIES;