http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49721
--- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> 2011-07-28 21:31:20 UTC --- (In reply to comment #2) > The question is we have > > (zero_extend:DI (plus:SI (FOO:SI) (const_int Y))) > > Is is OK to transform it to > > (plus:DI (zero_extend:DI (FOO:SI)) (const_int Y)) It is valid if addresses can never extend across singed SI_MAX and SI_MIN.