------- Comment #1 from pinskia at gcc dot gnu dot org 2008-09-24 00:35 ------- IIRC these are not documented because they can and will change at any time and don't always produce correct code.
Also you can use most of the builtin functions to get the same as the inline-asm ... -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37621
