do not backref empty string/array to save a few bytes

diff --git a/ion_private.h b/ion_private.h
index 29d45a74bfb19acc36f91d2810d30b5eb352c0f9..9b20fac9851905bef5a8f6c51459cb628dd302f0 100644 (file)
--- a/ion_private.h
+++ b/ion_private.h
@@ -1609,21 +1609,18 @@ static inline bool php_ion_serialize_system_value(php_ion_serializer *ser, zval
        return false;
 }
 
-static inline void php_ion_serialize_refcounted(php_ion_serializer *ser, zval *zv)
+static inline bool php_ion_serialize_backref(php_ion_serializer *ser, zval *zv)
 {
-       if (php_ion_serialize_system_value(ser, zv)) {
-               return;
+       if (Z_TYPE_P(zv) == IS_STRING && Z_STR_P(zv) == zend_empty_string) {
+               return false;
+       }
+       if (Z_TYPE_P(zv) == IS_ARRAY && Z_ARR_P(zv) == &zend_empty_array) {
+               return false;
        }
 
        zend_ulong idx = (zend_ulong) (uintptr_t) Z_COUNTED_P(zv);
-
-       ION_STRING is;
-       if (zend_hash_index_exists(ser->ids, idx)) {
-               zval *num = zend_hash_index_find(ser->ids, idx);
-
-               ION_CHECK(ion_writer_add_annotation_symbol(ser->writer, &PHP_ION_SYMBOL_BACKREF));
-               ION_CHECK(ion_writer_write_int64(ser->writer, Z_LVAL_P(num)));
-       } else {
+       zval *ref = zend_hash_index_find(ser->ids, idx);
+       if (!ref) {
                zval num;
 
                ZVAL_LONG(&num, zend_hash_num_elements(ser->ids));
@@ -1632,24 +1629,41 @@ static inline void php_ion_serialize_refcounted(php_ion_serializer *ser, zval *z
                Z_TRY_ADDREF_P(zv);
                zend_hash_next_index_insert(ser->tmp, zv);
 
-               switch (Z_TYPE_P(zv)) {
-               case IS_STRING:
-                       ION_CHECK(ion_writer_write_string(ser->writer, ion_string_from_zend(&is, Z_STR_P(zv))));
-                       break;
+               return false;
+       }
 
-               case IS_ARRAY:
-                       php_ion_serialize_array(ser, Z_ARRVAL_P(zv));
-                       break;
+       ION_CHECK_RETURN(true, ion_writer_add_annotation_symbol(ser->writer, &PHP_ION_SYMBOL_BACKREF));
+       ION_CHECK_RETURN(true, ion_writer_write_int64(ser->writer, Z_LVAL_P(ref)));
+       return true;
+}
 
-               case IS_OBJECT:
-                       php_ion_serialize_object(ser, Z_OBJ_P(zv));
-                       break;
+static inline void php_ion_serialize_refcounted(php_ion_serializer *ser, zval *zv)
+{
+       if (php_ion_serialize_system_value(ser, zv)) {
+               return;
+       }
+       if (php_ion_serialize_backref(ser, zv)) {
+               return;
+       }
 
-               case IS_REFERENCE:
-                       ION_CHECK(ion_writer_add_annotation_symbol(ser->writer, &PHP_ION_SYMBOL_REFERENCE));
-                       php_ion_serialize_zval(ser, Z_REFVAL_P(zv));
-                       break;
-               }
+       ION_STRING is;
+       switch (Z_TYPE_P(zv)) {
+       case IS_STRING:
+               ION_CHECK(ion_writer_write_string(ser->writer, ion_string_from_zend(&is, Z_STR_P(zv))));
+               break;
+
+       case IS_ARRAY:
+               php_ion_serialize_array(ser, Z_ARRVAL_P(zv));
+               break;
+
+       case IS_OBJECT:
+               php_ion_serialize_object(ser, Z_OBJ_P(zv));
+               break;
+
+       case IS_REFERENCE:
+               ION_CHECK(ion_writer_add_annotation_symbol(ser->writer, &PHP_ION_SYMBOL_REFERENCE));
+               php_ion_serialize_zval(ser, Z_REFVAL_P(zv));
+               break;
        }
 }