http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54146
--- Comment #20 from stevenb.gcc at gmail dot com <stevenb.gcc at gmail dot com> 2012-08-06 09:09:02 UTC --- On Mon, Aug 6, 2012 at 10:45 AM, rguenth at gcc dot gnu.org <gcc-bugzi...@gcc.gnu.org> wrote: > Ick, I suppose similar issues exist on the tree level for passes that > think that memory / compile-time usage O(number-of-ssa-names or basic-blocks) > is "ok" (and I suppose it really _is_ ok ...?) I think this is OK, yes. In general, anything linear in some measure of the function should be OK. NB, this thing in ifcvt is *not* O(max_reg_num()) but O(max_reg_num()*n_basic_blocks). I suspect that in the tree optimizers, a non-linear issue exists for rewriting into loop-closed SSA form. It looks like it is O(num_ssa_names*n_basic_blocks). I'm trying to confirm that (in my evening free time, so don't hold your breath ;-).
