On Mon, 30 May 2016, Tom de Vries wrote: > On 30/05/16 11:46, Richard Biener wrote: > > > This patch fixes the assert conservatively by aborting graphite code > > > >generation when encountering a phi with more than two arguments in > > > >copy_bb_and_scalar_dependences. > > > > > > > >Bootstrapped and reg-tested on x86_64. > > > > > > > >OK for trunk, 6 branch? > > > Did you check if simply returning false from bb_contains_loop_phi_nodes > > instead of asserting works? The caller has a 'else' that is supposed > > to handle condition PHIs. After all it already handles one predecessor > > specially ... Thus > > > > if (EDGE_COUNT (bb->preds) != 2) > > return false; > > > > should work here. > > Unfortunately, that doesn't work. We run into another assert in > copy_cond_phi_nodes: > ... > /* Cond phi nodes should have exactly two arguments. */ > gcc_assert (2 == EDGE_COUNT (bb->preds)); > ...
Hah. So can we still do my suggested change and bail out conservatively in Cond PHI node handling instead? Because the PHI node is clearly _not_ a loop header PHI and the cond phi assert is also a latent bug. > > Or replace this function with bb_loop_header_p (bb) > > (works w/o loop info, the function seems to depend on loop info and > > thus simply checking bb->loop_father->header == bb should work as well). > > I think that will run into the same assert. Yes. Richard. > Thanks, > - Tom > > > -- Richard Biener <rguent...@suse.de> SUSE LINUX GmbH, GF: Felix Imendoerffer, Jane Smithard, Graham Norton, HRB 21284 (AG Nuernberg)
