Kernel/RtlExtendedLargeIntegerDivide

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RtlExtendedLargeIntegerDivide will call RtlRaiseStatus(STATUS_INTEGER_DIVIDE_BY_ZERO) if Divisor = 0. Otherwise, a custom binary division algorithm is used to perform the divide operation. The algorithm below was reverse engineered from original hardware.

   LARGE_INTEGER quotient = Dividend;
   ULONG local_remainder = 0;
   BOOLEAN carry, remainder_carry;
   for (uint8_t i = 64; i > 0; i--) {
       carry = (quotient.QuadPart >> 63) & 0x1;
       remainder_carry = (local_remainder >> 31) & 0x1;
       quotient.QuadPart <<= 1;
       local_remainder = (local_remainder << 1) | carry;
       if (remainder_carry || (local_remainder >= Divisor)) {
           quotient.u.LowPart += 1;
           local_remainder -= Divisor;
       }
   }
   if (Remainder) {
       *Remainder = local_remainder;
   }