Gosh, I just had to enter this fray - especially since I have a complete set
of Microprocessor Reports going back to 1990.
In term of the most complex superscaler microprocessors in 1992, the most
significant were the 960MM, 88110 and the SuperSPARC. Now I quote:
"The 88110 has the most extensive partitioned and duplicated resource
organization of any superscaler microprocessor. It offers a branch/
instruction issue unit, a load/store unit, two integer units, a bit-field
shift unit, two graphics units, and three independent floating point units
(add, multiply and divide). The degree-two issue unit can simultaneously
dispatch two instructions to any two execution units with only minimal
exceptions."
"In addition to its impressive symmetry, the 88110 permits speculative
instruction issue and execution after a predicted branch. A register file
history buffer keeps track of registers so that they can be restored to their
pre-branch values if the branch is later discovered to have been
mis-predicted. Speculative execution allows the 88110 to extract the most
performance from its two issue capability"
Microprocessor Report, October 7, 1992
Lyle
On Thursday 13 November 2003 21:48, Eric Smith wrote:
> Peter Turnbull wrote:
> > Then I get three because I understood it, and can think of processors
> > that do it -- and a few more because I've not only got some (MIPS
> > R4600, R5K and R10K)
>
> None of which were available in November 1993. And having used the
> R4600 quite a bit in 1996, I'm fairly sure that it did *not* have
> speculative execution.
>
> > The Pentium can do speculative execution as well,
>
> The Pentium was superscalar, but did not do speculative execution.
> SE was introduced with the Pentium Pro, which was not introduced until
> 1995.
>
> I suspect that there were some processors with speculative execution
> before November 1993, but not microprocessors.
>
> I'm not convinced that you've earned your three extra geek points
> today, sorry.
>
> Eric
--
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 - 00:32:27 GMT