Add support for union types for internal functions

This closes the last hole in the supported types for internal
function arginfo types. It's now possible to represent unions of
multiple classes. This is done by storing them as TypeA|TypeB and
PHP will then convert this into an appropriate union type list.

Closes GH-6581.

1 files changed, 23 insertions, 12 deletions

diff --git a/Zend/zend_execute.c b/Zend/zend_execute.c
index 16eafc39ba..14ebcec1b7 100644
--- a/Zend/zend_execute.c
+++ b/Zend/zend_execute.c
@@ -951,6 +951,13 @@ ZEND_API zend_bool zend_value_instanceof_static(zval *zv) {
 	return instanceof_function(Z_OBJCE_P(zv), called_scope);
 }
 
+/* The cache_slot may only be NULL in debug builds, where arginfo verification of
+ * internal functions is enabled. Avoid unnecessary checks in release builds. */
+#if ZEND_DEBUG
+# define HAVE_CACHE_SLOT (cache_slot != NULL)
+#else
+# define HAVE_CACHE_SLOT 1
+#endif
 
 static zend_always_inline zend_bool zend_check_type_slow(
 		zend_type type, zval *arg, zend_reference *ref, void **cache_slot, zend_class_entry *scope,
@@ -962,31 +969,39 @@ static zend_always_inline zend_bool zend_check_type_slow(
 		if (ZEND_TYPE_HAS_LIST(type)) {
 			zend_type *list_type;
 			ZEND_TYPE_LIST_FOREACH(ZEND_TYPE_LIST(type), list_type) {
-				if (*cache_slot) {
+				if (HAVE_CACHE_SLOT && *cache_slot) {
 					ce = *cache_slot;
 				} else {
 					ce = zend_fetch_class(ZEND_TYPE_NAME(*list_type),
 						(ZEND_FETCH_CLASS_AUTO | ZEND_FETCH_CLASS_NO_AUTOLOAD));
 					if (!ce) {
-						cache_slot++;
+						if (HAVE_CACHE_SLOT) {
+							cache_slot++;
+						}
 						continue;
 					}
-					*cache_slot = ce;
+					if (HAVE_CACHE_SLOT) {
+						*cache_slot = ce;
+					}
 				}
 				if (instanceof_function(Z_OBJCE_P(arg), ce)) {
 					return 1;
 				}
-				cache_slot++;
+				if (HAVE_CACHE_SLOT) {
+					cache_slot++;
+				}
 			} ZEND_TYPE_LIST_FOREACH_END();
 		} else {
-			if (EXPECTED(*cache_slot)) {
+			if (EXPECTED(HAVE_CACHE_SLOT && *cache_slot)) {
 				ce = (zend_class_entry *) *cache_slot;
 			} else {
 				ce = zend_fetch_class(ZEND_TYPE_NAME(type), (ZEND_FETCH_CLASS_AUTO | ZEND_FETCH_CLASS_NO_AUTOLOAD));
 				if (UNEXPECTED(!ce)) {
 					goto builtin_types;
 				}
-				*cache_slot = (void *) ce;
+				if (HAVE_CACHE_SLOT) {
+					*cache_slot = (void *) ce;
+				}
 			}
 			if (instanceof_function(Z_OBJCE_P(arg), ce)) {
 				return 1;
@@ -1079,8 +1094,6 @@ static zend_never_inline ZEND_ATTRIBUTE_UNUSED bool zend_verify_internal_arg_typ
 
 	for (i = 0; i < num_args; ++i) {
 		zend_arg_info *cur_arg_info;
-		void *dummy_cache_slot = NULL;
-
 		if (EXPECTED(i < fbc->common.num_args)) {
 			cur_arg_info = &fbc->common.arg_info[i];
 		} else if (UNEXPECTED(fbc->common.fn_flags & ZEND_ACC_VARIADIC)) {
@@ -1090,7 +1103,7 @@ static zend_never_inline ZEND_ATTRIBUTE_UNUSED bool zend_verify_internal_arg_typ
 		}
 
 		if (ZEND_TYPE_IS_SET(cur_arg_info->type)
-				&& UNEXPECTED(!zend_check_type(cur_arg_info->type, arg, &dummy_cache_slot, fbc->common.scope, 0, /* is_internal */ 1))) {
+				&& UNEXPECTED(!zend_check_type(cur_arg_info->type, arg, /* cache_slot */ NULL, fbc->common.scope, 0, /* is_internal */ 1))) {
 			return 0;
 		}
 		arg++;
@@ -1215,8 +1228,6 @@ static ZEND_COLD void zend_verify_void_return_error(const zend_function *zf, con
 static bool zend_verify_internal_return_type(zend_function *zf, zval *ret)
 {
 	zend_internal_arg_info *ret_info = zf->internal_function.arg_info - 1;
-	void *dummy_cache_slot = NULL;
-
 	if (ZEND_TYPE_FULL_MASK(ret_info->type) & MAY_BE_VOID) {
 		if (UNEXPECTED(Z_TYPE_P(ret) != IS_NULL)) {
 			zend_verify_void_return_error(zf, zend_zval_type_name(ret), "");
@@ -1225,7 +1236,7 @@ static bool zend_verify_internal_return_type(zend_function *zf, zval *ret)
 		return 1;
 	}
 
-	if (UNEXPECTED(!zend_check_type(ret_info->type, ret, &dummy_cache_slot, NULL, 1, /* is_internal */ 1))) {
+	if (UNEXPECTED(!zend_check_type(ret_info->type, ret, /* cache_slot */ NULL, NULL, 1, /* is_internal */ 1))) {
 		zend_verify_internal_return_error(zf, ret);
 		return 0;
 	}