70's computers

[Paul Koning]

> On Oct 23, 2018, at 7:08 PM, Noel Chiappa via cctalk <cctalk at classiccmp.org> wrote:
> 
> ...
> There was a recent discussion about code density (I forget whether here, or
> on TUHS), and someone mentioned this paper:
> 
>  http://web.eece.maine.edu/~vweaver/papers/iccd09/iccd09_density.pdf
> 
> which shows that for a combo of benchmarks, the PDP-11 had the densest code
> out of all the ones they looked at. (They didn't look at the PDP-8, but I
> suspect that since it's a single-address design, it's almost ceertainly not
> as dense.)
> 
> The PDP-11 dates back to the days of core (it went through several generations
> before DRAM arrived - e.g. the -11/70 originally shipped with core), and given
> core prices, minimizing code size was pretty important - hence the results
> above.

What's interesting is that the paper uses compiled code.  The gcc back end for pdp11 is still a work in progress and clearly doesn't deliver best possible code, certainly not back then.

	paul