https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81611
--- Comment #17 from Alexandre Oliva <aoliva at gcc dot gnu.org> --- Created attachment 43025 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=43025&action=edit another complement to the initial partial patch, this one improving auto-inc-dec We already had code to turn the following into a post_inc: (set (reg A) (plus (reg B) (const_int I))) ... (mem (plus (reg A) (const_int -I))) ... so I've adjusted auto-inc-dec to also look for a (mem (reg B)) and deal with it in the same way. It worked beautifully for this one testcase. Let's see how a full bootstrap goes, on machines with auto-inc addressing modes...