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Supplements								  [TOC]
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Memory layout of a loaded program
=================================
Before a program gets executed the loader for the ULM reads in an executable and
initializes the memory of the ULM.  In general the memory layout of a program
consists of a text, data and BSS segment:

---- TIKZ ----------------------------------------------------------------------
\begin{tikzpicture}
\input{memory.tex}
\renewcommand\MemCellWidth { 0.2 }


%\DrawMemLabel{0}{Entry Point}
\DrawMemRange{0}{30}
\DrawMemVariable[gray!50]{0}{30}{ Text segment}

\DrawMemRange{30}{50}
\DrawMemVariable[orange]{30}{50}{ Data segment }

\DrawMemRange{50}{75}
\DrawMemVariable[blue!50]{50}{75}{ BSS segment }

\DrawMemArrayOpenRight{75}{100}

\end{tikzpicture}
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The loader setup the segments from the information provided in the program
file. The general format of a program file consists of sections that can be
empty:

---- TIKZ ----------------------------------------------------------------------
\begin{tikzpicture}

\node at (0, 0.25) {\color{white}.};
\node at (0, -5.25) {\color{white}.};
\node at (-.25, 0) {\color{white}.};
\node at (5.25, 0) {\color{white}.};

\draw (0,0) rectangle (5,-1);
\node at (2.5, -0.5) {text segment};

\draw (0,-1) rectangle (5,-2);
\node at (2.5, -1.5) {data segment};

\draw (0,-2) rectangle (5,-3);
\node at (2.5, -2.5) {BSS segment};

\draw (0,-3) rectangle (5,-4);
\node at (2.5, -3.5) {symbol table};

\draw (0,-4) rectangle (5,-5);
\node at (2.5, -4.5) {relocatable table};

\end{tikzpicture}
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