[db48x]

Oddly enough the unused bits are in the middle of the address. They're also sign-extended rather than filled with zeros, so sometimes they are ones and other times they are zeros.

[db48x]

In the middle of the address _space_, I should say.

[moonchild]

If you interpret your addresses as signed values, then the entire address space can be contiguous.

I'm not suggesting that this is a good idea, but is certainly an idea.

[db48x]

Negative addresses? Anathema!