Fix out-dated docs and typo

[ci skip]

Author: c9s

Zend/zend_compile.h

@@ -958,7 +958,7 @@ static zend_always_inline int zend_check_arg_send_type(const zend_function *zf,
 #define ARG_MAY_BE_SENT_BY_REF(zf, arg_num) \
 	zend_check_arg_send_type(zf, arg_num, ZEND_SEND_PREFER_REF)
 
-/* Quick API to check firat 12 arguments */
+/* Quick API to check first 12 arguments */
 #define MAX_ARG_FLAG_NUM 12
 
 #ifdef WORDS_BIGENDIAN

Zend/zend_execute.c

@@ -3261,7 +3261,7 @@ ZEND_API void zend_free_compiled_variables(zend_execute_data *execute_data) /* {
  *                             +========================================+
  * EG(current_execute_data) -> | zend_execute_data                      |
  *                             +----------------------------------------+
- *     EX_CV_NUM(0) ---------> | VAR[0] = ARG[1]                        |
+ *     EX_VAR_NUM(0) --------> | VAR[0] = ARG[1]                        |
  *                             | ...                                    |
  *                             | VAR[op_array->num_args-1] = ARG[N]     |
  *                             | ...                                    |
@@ -3274,6 +3274,15 @@ ZEND_API void zend_free_compiled_variables(zend_execute_data *execute_data) /* {
  *                             +----------------------------------------+
  */
 
+/* zend_copy_extra_args is used when the actually passed number of arguments
+ * (EX_NUM_ARGS) is greater than what the function defined (op_array->num_args).
+ *
+ * The extra arguments will be copied into the call frame after all the compiled variables.
+ *
+ * If there are extra arguments copied, a flag "ZEND_CALL_FREE_EXTRA_ARGS" will be set
+ * on the zend_execute_data, and when the executor leaves the function, the
+ * args will be freed in zend_leave_helper.
+ */
 static zend_never_inline void zend_copy_extra_args(EXECUTE_DATA_D)
 {
 	zend_op_array *op_array = &EX(func)->op_array;