}
-\frame{\frametitle{}
+\frame{\frametitle{Which Processor Cores to use?}
\begin{itemize}
- \item
- \item
- \item
+ \item Shakti RV64 at the top of the list, not just for technical
+ reasons, but for the Shakti Group's goals and vision.
+ \vspace{6pt}
+ \item Libre 3D GPGPU (SMP RV64 plus accelerated custom ISA)
+ would make things interesting\\
+ (3D app pinned to a non-uniform but SMP architecture)
+ \vspace{6pt}
+ \item Video Processing again is reasonable to be a different
+ RV32/64 Core (SMP or otherwise), possibly not even RV
+ at all (MIPS, OR1200)
+ \vspace{6pt}
+ \item RV32 (PicoRV32?) always-on definitely needed (sleep mode)
+ \vspace{6pt}
\end{itemize}
+ {\it Ultimately, decisions are flexible, heavily weighted
+ towards "what does good and doesn't do bad" as
+ well as cost vs risk
+ }
}
\frame{\frametitle{What's the value of SV? Why adopt it even in non-V?}
\begin{itemize}
- \item memcpy becomes much smaller (higher bang-per-buck)
+ \item memcpy has a much higher bang-per-buck ratio
\item context-switch (LOAD/STORE multiple): 1-2 instructions
\item Compressed instrs further reduces I-cache (etc.)
\item Reduced I-cache load (and less I-reads)
\begin{semiverbatim}
function op\_add(rd, rs1, rs2) # add not VADD!
int i, id=0, irs1=0, irs2=0;
+ predval = get\_pred\_val(FALSE, rd);
rd = int\_vec[rd ].isvector ? int\_vec[rd ].regidx : rd;
rs1 = int\_vec[rs1].isvector ? int\_vec[rs1].regidx : rs1;
rs2 = int\_vec[rs2].isvector ? int\_vec[rs2].regidx : rs2;
- predval = get\_pred\_val(FALSE, rd);
for (i = 0; i < VL; i++)
if (predval \& 1<<i) # predication uses intregs
ireg[rd+id] <= ireg[rs1+irs1] + ireg[rs2+irs2];