https://gcc.gnu.org/bugzilla/show_bug.cgi?id=116002
--- Comment #6 from Richard Biener <rguenth at gcc dot gnu.org> --- (In reply to Richard Biener from comment #5) > With -O2 we have PTA showing up > > tree PTA : 12.21 ( 77%) > > PTA solving should be pretty quick, but it seems we take a lot of iterations > for unknown reasons: > > 32.27% 20663 cc1 cc1 [.] topo_visit > 16.29% 10432 cc1 cc1 [.] solve_constraints > 14.69% 9412 cc1 cc1 [.] find > 14.10% 9021 cc1 cc1 [.] bitmap_clear_bit > 1.19% 764 cc1 cc1 [.] bitmap_set_bit the issue is that we have only constraints like _7 = &NONLOCAL e_30 = _7 + UNKNOWN e_30 = f_27 + UNKNOWN _8 = f_27 + UNKNOWN _8 = f_27 + UNKNOWN _9 = _8 + UNKNOWN those form a graph with N nodes and no copy edges as those constraints are all complex. Each solving iteration a few nodes get a new solution but those dependent have already been evaluated so we bottleneck on computing the optimal order to visit. I'm testing a patch for this.
