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@@ -180,6 +180,19 @@ This code shows that \texttt{\$regA} is replaced with \texttt{\$regB}. This
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way, the move instruction might have become useless, and it will then be
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removed by the dead code elimination.
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+\subsection{Dead code elimination}
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+
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+The final optimization that is performed is dead code elimination. This means
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+that when an instruction is executed, but the result is never used, that
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+instruction can be removed.
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+
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+To be able to properly perform dead code elimination, we need to know whether a
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+variable will be used, before it is overwritten again. If it does, we call the
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+variable live, otherwise the variable is dead. The technique to find out if a
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+variable is live is called liveness analysis. We implemented this for the
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+entire code, by analyzing each block, and using the variables that come in the
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+block live as the variables that exit its predecessor live.
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+
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\section{Implementation}
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We decided to implement the optimization in Python. We chose this programming
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Richard Torenvliet