\item Documentation of the ISA
\item Manual coding and optimisation
\item Time to support the platform
+ \item Compilance Suite development and testing
+ \item Protracted Variable-Length encoding (x86) severely compromises
+ Multi-issue decoding
\end{itemize}
\subsection{Simple Vectorisation}
\begin{itemize}
\item Introduce by implementing on top of existing Power ISA
\item Effectively a \textbf{hardware for-loop}, pauses main PC,
- issues multiple scalar op's
- \item Preserves underlying scalar execution dependencies as
- the for-loop had been expanded as actual scalar instructions
+ issues multiple scalar operations
+ \item Preserves underlying scalar execution dependencies as if
+ the for-loop had been expanded into actual scalar instructions
("preserving Program Order")
\item Augments existing instructions by adding "tags" - provides
Vectorisation "context" rather than adding new opcodes.
advantage in the vector space (see \ref{subsubsec:add_to_pow_isa})
\item Aimed at Supercomputing: avoids creating significant
\textit{sequential dependency hazards}, allowing \textbf{high
- performance superscalar microarchitectures} to be deployed.
+ performance multi-issue superscalar microarchitectures} to be
+ leveraged.
\end{itemize}
Advantages include: