Zend: add consume_params support for fcall arguments

Author: drealecs

Zend/zend_API.c

@@ -1023,6 +1023,7 @@ static const char *zend_parse_arg_impl(zval *arg, va_list *va, const char **spec
 
 				if (check_null && Z_TYPE_P(arg) == IS_NULL) {
 					fci->size = 0;
+					fci->consume_params = 0;
 					fcc->function_handler = 0;
 					break;
 				}
@@ -4238,6 +4239,7 @@ ZEND_API zend_result zend_fcall_info_init(zval *callable, uint32_t check_flags,
 	fci->param_count = 0;
 	fci->params = NULL;
 	fci->named_params = NULL;
+	fci->consume_params = 0;
 
 	return SUCCESS;
 }

Zend/zend_API.h

@@ -54,6 +54,7 @@ typedef struct _zend_fcall_info {
 	 * integrate APIs like call_user_func_array(). The usual restriction that
 	 * there may not be position arguments after named arguments applies. */
 	HashTable *named_params;
+	uint32_t consume_params;
 } zend_fcall_info;
 
 typedef struct _zend_fcall_info_cache {
@@ -339,6 +340,7 @@ typedef struct _zend_fcall_info_cache {
 
 #define ZEND_FCI_INITIALIZED(fci) ((fci).size != 0)
 #define ZEND_FCC_INITIALIZED(fcc) ((fcc).function_handler != NULL)
+#define ZEND_FCI_CONSUME_PARAM(arg_num) (1u << ((arg_num) - 1))
 
 ZEND_API int zend_next_free_module(void);
 
@@ -2486,6 +2488,7 @@ static zend_always_inline bool zend_parse_arg_func(zval *arg, zend_fcall_info *d
 {
 	if (check_null && UNEXPECTED(Z_TYPE_P(arg) == IS_NULL)) {
 		dest_fci->size = 0;
+		dest_fci->consume_params = 0;
 		dest_fcc->function_handler = NULL;
 		*error = NULL;
 	} else if (UNEXPECTED(zend_fcall_info_init(arg, 0, dest_fci, dest_fcc, NULL, error) != SUCCESS)) {

Zend/zend_closures.c

@@ -155,6 +155,7 @@ ZEND_METHOD(Closure, call)
 	fci_cache.object = fci.object = newobj;
 
 	fci.size = sizeof(fci);
+	fci.consume_params = 0;
 	ZVAL_OBJ(&fci.function_name, &closure->std);
 	ZVAL_UNDEF(&closure_result);
 	fci.retval = &closure_result;

Zend/zend_exceptions.c

@@ -687,6 +687,7 @@ ZEND_METHOD(Exception, __toString)
 	fci.params = NULL;
 	fci.object = NULL;
 	fci.named_params = NULL;
+	fci.consume_params = 0;
 
 	zend_fcall_info_cache fcc;
 	fcc.function_handler = getTraceAsString;

Zend/zend_execute_API.c

@@ -797,6 +797,7 @@ zend_result _call_user_function_impl(zval *object, zval *function_name, zval *re
 	fci.param_count = param_count;
 	fci.params = params;
 	fci.named_params = named_params;
+	fci.consume_params = 0;
 
 	return zend_call_function(&fci, NULL);
 }
@@ -869,6 +870,7 @@ zend_result zend_call_function(zend_fcall_info *fci, zend_fcall_info_cache *fci_
 		zval *param = ZEND_CALL_ARG(call, i+1);
 		zval *arg = &fci->params[i];
 		bool must_wrap = false;
+		bool consume_arg = i < 32 && ((fci->consume_params >> i) & 1);
 		if (UNEXPECTED(Z_ISUNDEF_P(arg))) {
 			/* Allow forwarding undef slots. This is only used by Closure::__invoke(). */
 			ZVAL_UNDEF(param);
@@ -905,7 +907,12 @@ zend_result zend_call_function(zend_fcall_info *fci, zend_fcall_info_cache *fci_
 		}
 
 		if (EXPECTED(!must_wrap)) {
-			ZVAL_COPY(param, arg);
+			if (consume_arg && !Z_ISREF_P(arg) && arg == &fci->params[i]) {
+				ZVAL_COPY_VALUE(param, arg);
+				ZVAL_UNDEF(arg);
+			} else {
+				ZVAL_COPY(param, arg);
+			}
 		} else {
 			Z_TRY_ADDREF_P(arg);
 			ZVAL_NEW_REF(param, arg);
@@ -1091,6 +1098,7 @@ ZEND_API void zend_call_known_function(
 	fci.param_count = param_count;
 	fci.params = params;
 	fci.named_params = named_params;
+	fci.consume_params = 0;
 	ZVAL_UNDEF(&fci.function_name); /* Unused */
 
 	fcic.function_handler = fn;

Zend/zend_gc.c

@@ -1922,6 +1922,7 @@ static zend_fiber *gc_create_destructor_fiber(void)
 
 	fiber = (zend_fiber *)Z_OBJ(zobj);
 	fiber->fci.size = sizeof(fiber->fci);
+	fiber->fci.consume_params = 0;
 	fiber->fci_cache.function_handler = (zend_function*) &gc_destructor_fiber;
 
 	GC_G(dtor_fiber) = fiber;

ext/dom/xpath_callbacks.c

@@ -408,6 +408,7 @@ static zend_result php_dom_xpath_callback_dispatch(php_dom_xpath_callbacks *xpat
 		fci.param_count = param_count;
 		fci.params = params;
 		fci.named_params = NULL;
+		fci.consume_params = 0;
 		ZVAL_STRINGL(&fci.function_name, function_name, function_name_length);
 
 		zend_call_function(&fci, NULL);

ext/ffi/ffi.c

@@ -950,6 +950,7 @@ static void zend_ffi_callback_trampoline(ffi_cif* cif, void* ret, void** args, v
 	fci.object = NULL;
 	fci.param_count = callback_data->arg_count;
 	fci.named_params = NULL;
+	fci.consume_params = 0;
 
 	if (callback_data->type->func.args) {
 		int n = 0;