function_exists    55 Zend/zend_builtin_functions.c static ZEND_FUNCTION(function_exists);
function_exists   282 Zend/zend_builtin_functions.c 	ZEND_FE(function_exists,	arginfo_function_exists)
function_exists  1535 Zend/zend_builtin_functions.c ZEND_FUNCTION(function_exists)