https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82627
--- Comment #5 from Richard Biener <rguenth at gcc dot gnu.org> --- What ISL version are you using? We have the same IL before ISL but the transformed schedule is different and for some reason the AST generator biases one IV by one. Before the rev. ISL did even more weird stuff to this testcase for you. Please make sure to use ISL 0.18.