Test

(int, int, int) compute_data_size(cell c, int max_cells) impure asm "CDATASIZE";
(int, int, int) slice_compute_data_size(slice s, int max_cells) impure asm "SDATASIZE";
(int, int, int, int) compute_data_size?(cell c, int max_cells) asm "CDATASIZEQ NULLSWAPIFNOT2 NULLSWAPIFNOT";
(int, int, int, int) slice_compute_data_size?(cell c, int max_cells) asm "SDATASIZEQ NULLSWAPIFNOT2 NULLSWAPIFNOT";