> +/* Returns whether the control parents of BB are preserved. */ > + > +static bool > +control_parents_preserved_p (basic_block bb) > +{ > + /* If we marked the control parents from BB they are preserved. */ > + if (bitmap_bit_p (visited_control_parents, bb->index)) > + return true; > + > + /* But they can also end up being marked from elsewhere. */ > + bitmap_iterator bi; > + unsigned edge_number; > + EXECUTE_IF_SET_IN_BITMAP (cd->get_edges_dependent_on (bb->index), > + 0, edge_number, bi) > + { > + basic_block cd_bb = cd->get_edge_src (edge_number); > + if (cd_bb != bb > + && !bitmap_bit_p (last_stmt_necessary, cd_bb->index)) > + return false; > + } > + return true; I suppose you can also set visited_control_parents bit here so the loop is not re-done for every clobber in a BB.
Honza