Re: is Vax addressing sane today

Lawrence D'Oliveiro <ldo@nz.invalid> writes:

On Mon, 9 Sep 2024 04:38:42 -0000 (UTC), Brett wrote:

The next step up for a CPU has one ALU and one load/store unit, giving
above one IPC. This is what one of the PlayStation CPU’s did.

>
Those were the ones using PowerPC chips in the 1990s, I think it was.

The first PlayStation used a 33MHz R3000 (single-issue).

The PS2 released in 2000 used a 299MHz MIPS R5900-based core, two-way in-order
superscalar.

The PS3 released in 2006 used the PowerPC-based Cell broadband engine.

IBM’s POWER claimed superscalar performance right from its launch in, what
was it, 1989.

1990.

It's interesting that it took so long to go to dual-issue with the
same number of functional units.  I guess that the early RISCs were
bandwidth-limited, and only once the L1 cache(s) came on-chip, was
there enough bandwidth to make superscalarity actually pay off.

- anton
--
'Anyone trying for "industrial quality" ISA should avoid undefined behavior.'
  Mitch Alsup, <c17fcd89-f024-40e7-a594-88a85ac10d20o@googlegroups.com>