Is there any reason why arithmetic operation on shorts and bytes return int?

[d coder]

Greetings

The following code prints FFFF0000. Similar thing happens when a and b are
bytes.
Is this intended?

Regards
- Puneet

void main()
{
  import std.stdio;
  ushort a = 0x55AA;
  ushort b = 0xAA55;
  writefln("%X", ~(a | b));
}