uECC_VLI_API bitcount_t uECC_vli_numBits(const uECC_word_t *vli, const wordcount_t max_words) {
    uECC_word_t i;
    uECC_word_t digit;

    wordcount_t num_digits = vli_numDigits(vli, max_words);
    if (num_digits == 0) {
        return 0;
    }

    digit = vli[num_digits - 1];
    for (i = 0; digit; ++i) {
        digit >>= 1;
    }

    return (((bitcount_t)(num_digits - 1) << uECC_WORD_BITS_SHIFT) + i);
}