- BM_mesh_elem_toolflags_ensure / bmo_flag_layer_alloc / bmo_flag_layer_free / bmo_flag_layer_clear - BM_mesh_select_flush - EDBM_index_arrays_init notes: - mostly use openmp `sections` to split operations on vert/edge/face since this is a fairly minor change. - split tool flag pool in 3, this means we can allocate exact sizes needed and iterate on them in threads without alloc'ing.