Re: Stealing a Great Idea from the 6600

John Savard wrote:

On Sat, 20 Apr 2024 22:03:21 +0000, mitchalsup@aol.com (MitchAlsup1)
wrote:

BGB wrote:

   Sign-extend signed values, zero-extend unsigned values.

Another mistake I mad in Mc 88100.

As that is a mistake the IBM 360 made, I make it too. But I make it
the way the 360 did: there are no signed and unsigned values, in the
sense of a Burroughs machine, there are just Load, Load Unsigned - and
Insert - instructions.

Index and base register values are assumed to be unsigned.

I would use the term signless as opposed to unsigned.
Address arithmetic is ADD only and does not care about signs or
overflow. There is no concept of a negative base register or a
negative index register (or, for that matter, a negative displace-
ment), overflow, underflow, carry, ...

John Savard