Function opnd_size_from_bytes 

pub unsafe extern "C" fn opnd_size_from_bytes(
    bytes: uint,
) -> opnd_size_t

Returns the appropriate OPSZ_ constant for the given number of bytes. Returns OPSZ_NA if there is no such constant. The intended use case is something like “opnd_size_in_bytes(sizeof(foo))” for integer/pointer types. This routine returns simple single-size types and will not return complex/variable size types.