Re: Why ssse3?

Andi Kleen
2007-05-03T09:07:45Z

On Thursday 03 May 2007 11:02:31 Avi Kivity wrote:
> Andi Kleen wrote:
> > On Thursday 03 May 2007 00:56:26 Ulrich Drepper wrote:
> >
> >> Andi Kleen wrote:
> >>
> >>> Nope. SSE3 != SSSE3. The additional S means Supplemential.
> >>>
> >>> It's probably because the few changes didn't justify a SSE4
> >>>
> >> OK, the problem is that the actual sse3 bit is misnamed. According to
> >> Intel's docs bit 0 of ECX is "sse", the kernel uses "pni". Too bad.
> >>
> >
> > PNI (Prescott New Instructions) was the original engineering code name. Unfortunately
> > it was added too early before the marketing name was known and then it couldn't be
> > changed anymore.
> >
>
> Perhaps sse3 could be added as an alias to pni.

That was considered at some point, but it would be a ugly special case and is
probably not worth it. Usually these flags are Greek for most people anyways
(and something else for the Greek speaking people @)

-Andi