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diff --git a/manual/PRESENTATION_ExAdv.tex b/manual/PRESENTATION_ExAdv.tex index 74f0e82c..8457ceb7 100644 --- a/manual/PRESENTATION_ExAdv.tex +++ b/manual/PRESENTATION_ExAdv.tex @@ -24,7 +24,155 @@ This section contains 4 subsections: \subsectionpagesuffix \end{frame} -\subsubsection{TBD} +\subsubsection{Simple selections} + +\begin{frame}[fragile]{\subsubsecname} +Most Yosys commands make use of the ``selection framework'' of Yosys. It can be used +to apply commands only to part of the design. For example: + +\medskip +\begin{lstlisting}[xleftmargin=0.5cm, basicstyle=\ttfamily\fontsize{8pt}{10pt}\selectfont, language=ys] +delete # will delete the whole design, but + +delete foobar # will only delete the module foobar. +\end{lstlisting} + +\bigskip +The {\tt select} command can be used to create a selection for subsequent +commands. For example: + +\medskip +\begin{lstlisting}[xleftmargin=0.5cm, basicstyle=\ttfamily\fontsize{8pt}{10pt}\selectfont, language=ys] +select foobar # select the module foobar +delete # delete selected objects +select -clear # reset selection (select whole design) +\end{lstlisting} +\end{frame} + +\subsubsection{Selection by object name} + +\begin{frame}[fragile]{\subsubsecname} +The easiest way to select objects is by object name. This is usually only done +in synthesis scripts that are hand-tailored for a specific design. + +\bigskip +\begin{lstlisting}[xleftmargin=0.5cm, basicstyle=\ttfamily\fontsize{8pt}{10pt}\selectfont, language=ys] +select foobar # select module foobar +select foo* # select all modules whose names start with foo +select foo*/bar* # select all objects matching bar* from modules matching foo* +select */clk # select objects named clk from all modules +\end{lstlisting} +\end{frame} + +\subsubsection{Module and design context} + +\begin{frame}[fragile]{\subsubsecname} +Commands can be executed in {\it module\/} or {\it design\/} context. Until now all +commands have been executed in design context. The {\tt cd} command can be used +to switch to module context. + +\bigskip +In module context all commands only effect the active module. Objects in the module +are selected without the {\tt <module\_name>/} prefix. For example: + +\bigskip +\begin{lstlisting}[xleftmargin=0.5cm, basicstyle=\ttfamily\fontsize{8pt}{10pt}\selectfont, language=ys] +cd foo # switch to module foo +delete bar # delete object foo/bar + +cd mycpu # switch to module mycpu +dump reg_* # print details on all objects whose names start with reg_ + +cd .. # switch back to design +\end{lstlisting} + +\bigskip +Note: Most synthesis script never switch to module context. But it is a very powerful +tool for interactive design investigation. +\end{frame} + +\subsubsection{Selecting by object property or type} + +\begin{frame}[fragile]{\subsubsecname} +Special pattern can be used to select by object property or type. For example: + +\bigskip +\begin{lstlisting}[xleftmargin=0.5cm, basicstyle=\ttfamily\fontsize{8pt}{10pt}\selectfont, language=ys] +select w:reg_* # select all wires whose names start with reg_ +select a:foobar # select all objects with the attribute foobar set +select a:foobar=42 # select all objects with the attribute foobar set to 42 +select A:blabla # select all module with the attribute blabla set +select foo/t:$add # select all $add cells from the module foo +\end{lstlisting} + +\bigskip +A complete list of this pattern expressions can be found in the command +reference to the {\tt select} command. +\end{frame} + +\subsubsection{Combining selection} + +\begin{frame}[fragile]{\subsubsecname} +When more than one selection expression is used in one statement they are +pushed on a stack. At the final elements on the stack are combined into a union: + +\medskip +\begin{lstlisting}[xleftmargin=0.5cm, basicstyle=\ttfamily\fontsize{8pt}{10pt}\selectfont, language=ys] +select t:$dff r:WIDTH>1 # all cells of type $dff and/or with a parameter WIDTH > 1 +\end{lstlisting} + +\bigskip +Special \%-commands can be used to combine the elements on the stack: + +\medskip +\begin{lstlisting}[xleftmargin=0.5cm, basicstyle=\ttfamily\fontsize{8pt}{10pt}\selectfont, language=ys] +select t:$dff r:WIDTH>1 %i # all cells of type $dff *AND* with a parameter WIDTH > 1 +\end{lstlisting} + +\medskip +\begin{block}{Examples for {\tt \%}-codes (see {\tt help select} for full list)} +{\tt \%u} \dotfill union of top two elements on stack -- pop 2, push 1 \\ +{\tt \%d} \dotfill difference of top two elements on stack -- pop 2, push 1 \\ +{\tt \%i} \dotfill intersection of top two elements on stack -- pop 2, push 1 \\ +{\tt \%n} \dotfill inverse of top element on stack -- pop 1, push 1 \\ +\end{block} +\end{frame} + +\subsubsection{Expanding selections} + +\begin{frame}[fragile]{\subsubsecname} +Selections of cells and wires can be expanded along connections using {\tt \%}-codes +for selecting input cones ({\tt \%ci}), output cones ({\tt \%co}), or both ({\tt \%x}). + +\medskip +\begin{lstlisting}[xleftmargin=0.5cm, basicstyle=\ttfamily\fontsize{8pt}{10pt}\selectfont, language=ys] +# select all wires that are inputs to $add cells +select t:$add %ci w:* %i +\end{lstlisting} + +\bigskip +Additional constraints such as port names can be specified. + +\medskip +\begin{lstlisting}[xleftmargin=0.5cm, basicstyle=\ttfamily\fontsize{8pt}{10pt}\selectfont, language=ys] +# select all wires that connect a "Q" output with a "D" input +select c:* %co:+[Q] w:* %i c:* %ci:+[D] w:* %i %i + +# select the multiplexer tree that drives the signal 'state' +select state %ci*:+$mux,$pmux[A,B,Y] +\end{lstlisting} + +\bigskip +See {\tt help select} for full documentation of this expressions. +\end{frame} + +\subsubsection{Incremental selection} + +\begin{frame}{\subsubsecname} +TBD +\end{frame} + +\subsubsection{Creating selection variables} \begin{frame}{\subsubsecname} TBD |