Function executor_storage_u64_len 

pub const fn executor_storage_u64_len(
    cbs: usize,
    sc: usize,
    arena: usize,
) -> usize

Number of u64 words a backing must hold for a (cbs, sc, arena)-sized executor. u64 backing is 8-aligned, which covers every field (all align_of ≤ 8; asserted in tests), so the entry never hand-aligns. The macro emits [MaybeUninit<u64>; executor_storage_u64_len(N, SC, A)].