According to a chart in Microprocessor Report identifying the attributes of
all the major superscaler microprocessor chips available as of October, 1992,
only the Motorola 88110 had speculative execution.
Back in the sixties, I was working at IBM's Development Lab in Poughkeepsie,
NY when we (IBM) announced the IBM 360/91 - which one could argue was the
first computer that explored superscaler techniques (Of course, it was
definitely NOT a microprocessor ;-)
Of course, some CDC folks might argue with me on who was first :-)
BTW: I used the "Nancy" simulator (simulating 360 architecture) on the IBM
Stretch to develop an early diagnostic OS for the 360 - and for sure the
early 360's could not be considered superscaler - although I would argue that
Stretch itself was "close"...
Cheers,
Lyle
On Friday 14 November 2003 05:35, Eric Smith wrote:
> > I thought the R4600 was, though maybe it was early 1994, but actually I
> > wasn't claiming any particular date
>
> There's no challenge in naming a few parts that have speculative
> execution. In my original posting, I specifically stated that I
> couldn't think of any processors introduced before Nov. 1993 that
> had speculative execution, other than the IBM 7030 (Stretch, 1961).
>
> I wasn't claiming that there weren't any others, just that I didn't
> know of any. I was *almost* willing to claim that there weren't any
> microprocessors with speculative execution until after Nov. 1993.
>
> However, I may have been a bit hasty. Although I don't think the
> R4600 was out at that time, after thinking about it some more it
> occurs to me that some earlier R4K series parts may have had
> speculative execution, and probably the DEC Alpha (20164). So if
> I were the arbiter for geek points, I guess I'd have to give you at
> least partial credit. :-)
>
> > I meant the Pentium family.
>
> Is there really a Pentium family? Aside from the Pentium Pro,
> Pentium II, and Pentium 3, which use similar cores, there seems to be
> little microarchitectural similarity between parts for which Intel uses
> the "Pentium" name. For instance, there seems to be more similarity
> between the i486 and Pentium cores than between the Pentium III and
> Pentium IV cores, despite the fact that the Pentium was superscalar
> and the i486 was not.
--
Lyle Bickley
Bickley Consulting West Inc.
Mountain View, CA 94040
"Black holes are where God is dividing by zero"
Received on Fri Nov 14 2003 - 09:33:05 GMT