On Tue, Jan 11, 2022 at 7:41 PM Vladimir Makarov via Gcc-patches <gcc-patches@gcc.gnu.org> wrote: > > > On 2022-01-11 12:42, Richard Sandiford wrote: > > The new IRA heuristics would need more work on old-reload targets, > > since flattening needs to be able to undo the cost propagation. > > It's doable, but hardly seems worth it. > Agree. It is not worth to spend your time for work for reload. > > This patch therefore makes all the new calls to > > ira_subloop_allocnos_can_differ_p return false if !ira_use_lra_p. > > The color_pass code that predated the new function (and that was > > the source of ira_subloop_allocnos_can_differ_p) continues to > > behave as before. > > > > It's a hack, but at least it has the advantage that the new parameter > > would become obviously unused if reload and (!)ira_use_lra_p were > > removed. The hack should therefore disappear alongside reload. > I have a feeling that it will stay for a long time if not forever.
We indeed seem to have 34 targets w/o LRA by default and only 15 with :/ At some point Eric wrote a nice summary for how to transition targets away from CC0, I wonder if there's something similar for transitioning a port away from reload to LRA? In those 34 targets there must be some for which that's a relatively easy task? I suppose it depends on how much of the reload target hooks are put to use and how those translate to LRA. Richard.
