https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108459
--- Comment #4 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
I think that ought to be fine.
There is
if (single_nonrect == -1
|| (loop->m1 && TREE_CODE (loop->m1) != INTEGER_CST)
|| (loop->m2 && TREE_CODE (loop->m2) != INTEGER_CST)
|| TREE_CODE (loop->n1) != INTEGER_CST
|| TREE_CODE (loop->n2) != INTEGER_CST
|| TREE_CODE (loop->step) != INTEGER_CST)
{
count = NULL_TREE;
continue;
}
some lines above that, after all, it is also using fold_binary rather than
fold_build2 etc. All that code is there to compute the constant number of
iterations and other helper values for non-rectangular loops with all constant
expressions.
