[gnu8]

This is almost surely a dumb question, but what would happen if someone made a processor that only executed mov instructions, which would be extremely simple, and presumably would be really goddamn fast. Would that be competitive with today's fastest CPUs? If it were, what would be the advantages and disadvantages of this design?

[gizmo686]

Well, Turing machines do not have random access memory (which changes the big-theta complexity of algorithms), and that operations such as multiplications would be complicated and multi-cycle, whereas conventional CPUs can easily parralize them.

If you were comparing the performs of mov-only programs, a specialized cpu would likely be faster. Otherwise, there is a good reason we do not actually use Turing machines.

[sklogic]

An extreme example:

http://laughtonelectronics.com/Arcana/One-bit%20computer/One...

A bit less extreme: http://www.sccs.swarthmore.edu/users/06/adem/engin/e25/final...

[userbinator]

what would happen if someone made a processor that only executed mov instructions, which would be extremely simple, and presumably would be really goddamn fast.

The laws of physics get in the way. It's essentially the same reason why clock frequencies have stopped going up.

[0xe2-0x9a-0x9b]

"a processor that only executed mov instructions, which would be extremely simple"

I believe such a CPU wouldn't end up simple due to competition for better performance. It would end up being more complex than x86 CPUs.

[asdfaoeu]

Might want to look at the examples. They turn an equality check into two register stores and a load.