rs6000: Corrects comments which are added by r13-4423

gcc/
	* config/rs6000/rs6000-call.cc (swap_endian_selector_for_mode):
	Corrects comments of this function and make them clear.

diff --git a/gcc/config/rs6000/rs6000-call.cc b/gcc/config/rs6000/rs6000-call.cc
index c2a4e4f4e27116436a066870c85c5f493d9fa46a..59c51fa35795f44c8d7f8951c491be9e2eec79a6 100644 (file)
--- a/gcc/config/rs6000/rs6000-call.cc
+++ b/gcc/config/rs6000/rs6000-call.cc
@@ -2802,8 +2802,10 @@ rs6000_gimplify_va_arg (tree valist, tree type, gimple_seq *pre_p,
   return build_va_arg_indirect_ref (addr);
 }
 
-/* The selector (perm) is expected to be used with vperm direct as the
-   function generates reversed perm for little endian with this patch.  */
+/* Return the permutation index for the swapping on the given vector mode.
+   Note that the permutation index is correspondingly generated by endianness,
+   it should be used by direct vector permutation.  */
+
 rtx
 swap_endian_selector_for_mode (machine_mode mode)
 {