Function Hacl_Chacha20_Vec256_chacha20_decrypt_256 

pub unsafe extern "C" fn Hacl_Chacha20_Vec256_chacha20_decrypt_256(
    len: u32,
    out: *mut u8,
    cipher: *mut u8,
    key: *mut u8,
    n: *mut u8,
    ctr: u32,
)