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@@ -35,7 +35,7 @@ the keywords in to an action.
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\section{Design}
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\section{Design}
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-There are two general types of of optimizations of the assembly code, global
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+There are two general types of optimizations of the assembly code, global
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optimizations and optimizations on a so-called basic block. These optimizations
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optimizations and optimizations on a so-called basic block. These optimizations
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will be discussed separately
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will be discussed separately
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@@ -99,6 +99,14 @@ Appendix \ref{opt}.
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A more advanced optimization is common subexpression elimination. This means
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A more advanced optimization is common subexpression elimination. This means
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that expensive operations as a multiplication or addition are performed only
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that expensive operations as a multiplication or addition are performed only
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once and the result is then `copied' into variables where needed.
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once and the result is then `copied' into variables where needed.
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+\begin{verbatim}
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+non-optimized:
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+addu $2,$2,$3
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+addu $4,$2,$3
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+
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+optimized:
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+
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+\end{verbatim}
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A standard method for doing this is the creation of a DAG or Directed Acyclic
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A standard method for doing this is the creation of a DAG or Directed Acyclic
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Graph. However, this requires a fairly advanced implementation. Our
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Graph. However, this requires a fairly advanced implementation. Our
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Richard Torenvliet