[Libre-soc-dev] All div pipe tests pass

[Cole Poirier]

On Fri, Oct 9, 2020 at 10:09 AM Luke Kenneth Casson Leighton
<lkcl at lkcl.net> wrote:
> On Fri, Oct 9, 2020 at 6:03 PM Jacob Lifshay <programmerjake at gmail.com> wrote:
>
> > well, the modsw instruction has similar behavior -- sign-extending the
> > result in all cases when the spec leaves the top 32-bits undefined.
>
> ahh interesting.  sigh all of these fall into "Ahmdahl nightmare
> scenario".  i'm amazed anyone hasn't pointed that out before, or made
> a fuss about it.

I've heard of Ahmdahl's law in terms of parallel scaling before, but I
can't quite understand the above, can you enlighten me as to why this
sign extension behaviour falls into Ahmdahl nightmare scenario?

Cole

Cole