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Progress on AppNote 011

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Clifford Wolf 2013-12-02 12:54:21 +01:00
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manual/APPNOTE_011_Design_Investigation.tex
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@ -654,11 +654,60 @@ See {\tt help select} for a complete list of actions available in selections.
\subsection{Storing and recalling selections}
\FIXME{}
The current selection can be stored in memory with the command {\tt select -set
<name>}. It can later be recalled using {\tt select @<name>}. In fact, the {\tt
@<name>} expression pushes the stored selection on the stack maintained by the
{\tt select} command. So for example
\begin{verbatim}
select @foo @bar %i
\end{verbatim}
will select the intersection between the stored selections {\tt foo} and {\tt bar}.
\medskip
In larger investigation efforts it is highly recommended to maintain a script that
sets up relevant selections, so they can easily be recalled, for example when
Yosys needs to be re-run after a design or source code change.
The {\tt history} command can be used to list all recent interactive commands.
A feature that can be useful to create such a script from the commands used in
an interactive session.
\section{Advanced investigation techniques}
\label{poke}
When working with very large modules, it is often not enough to just select the
interesting part of the module. Instead it can be useful to extract the
interesting part of the circuit into a separate module. This can for example be
useful if one wants to run a series of synthesis commands on the critical part
of the module and wants to carefully read all the debug output created by the
commands in order to spot a problem. This kind of troubleshooting is much easier
if the circuit under investigation is encapsulated in a separate module.
\begin{figure}[b]
\includegraphics[width=\linewidth,trim=0 0cm 0 0cm]{APPNOTE_011_Design_Investigation/submod_00.pdf} \\ \centerline{\tt memdemo} \vskip1em
\includegraphics[width=\linewidth,trim=0 0cm 0 0cm]{APPNOTE_011_Design_Investigation/submod_01.pdf} \\ \centerline{\tt scramble} \vskip1em
\includegraphics[width=\linewidth,trim=0 0cm 0 0cm]{APPNOTE_011_Design_Investigation/submod_02.pdf} \\ \centerline{\tt outstage} \vskip1em
\includegraphics[width=\linewidth,trim=0 0cm 0 0cm]{APPNOTE_011_Design_Investigation/submod_03.pdf} \\ \centerline{\tt selstage} \vskip1em
\begin{lstlisting}[basicstyle=\ttfamily\scriptsize]
select -set outstage y %ci2:+$dff[Q,D] %ci*:-$mux[S]:-$dff
select -set selstage y %ci2:+$dff[Q,D] %ci*:-$dff @outstage %d
select -set scramble mem* %ci2 %ci*:-$dff mem* %d @selstage %d
submod -name scramble @scramble
submod -name outstage @outstage
submod -name selstage @selstage
\end{lstlisting}
\caption{The circuit from Fig.~\ref{memdemo_src} and \ref{memdemo_00} broken up using {\tt submod}}
\label{submod}
\end{figure}
\FIXME{} --- submod, eval, sat
\section{Conclusion}