set_irg_block_visited(current_ir_graph, /* Don't walk all the way to Start. */
get_irg_block_visited(current_ir_graph)-1);
irg_block_walk(ka, optimize_blocks, NULL, NULL);
mark_irn_visited(ka);
set_irg_block_visited(current_ir_graph, /* Don't walk all the way to Start. */
get_irg_block_visited(current_ir_graph)-1);
irg_block_walk(ka, optimize_blocks, NULL, NULL);
mark_irn_visited(ka);