25 Jul
2014
25 Jul
'14
9:09 p.m.
On Fri, Jul 25, 2014 at 7:47 PM, Jon Elson <elson at pico-systems.com> wrote:
I think most modern, high performance CPUs do not use
microcode,
as the two-stage instruction execution would be slower than
just doing the decode in pure logic.
That's true if you don't consider x86 processors to be "modern high
performance CPUs". All Intel and AMD x86 processors have microcode,
and I suspect that those from other vendors do as well. Depending on
how you specifically define "microcode", they don't use it for all
instructions, but they do use it for some.
If they didn't use microcode, they wouldn't need microcode patches!
Eric