Method CountLeadingBinaryZeros

cpp/src/arrow/util/basic_decimal.cc:391–393

template <typename BaseType>
int32_t SmallBasicDecimal<BaseType>::CountLeadingBinaryZeros() const {
  return std::countl_zero(static_cast<std::make_unsigned_t<BaseType>>(value_));
}

// same as kDecimal128PowersOfTen[38] - 1
static constexpr BasicDecimal128 kMaxDecimal128Value{5421010862427522170LL,