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<title>C.1 Generating prefix sequences</title>

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<h2>
  <a name="1051078"> </a><font color="#003366"  face="Verdana, Arial, Helvetica, sans-serif">C.1 	 Generating prefix sequences</font>
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<p>
  <a name="1051079"> </a><font size=2  face="Verdana, Arial, Helvetica, sans-serif">Prefixing is intended to be performed by a compiler or assembler. Prefixing by hand is not advised.</font>
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<p>
  <a name="1051080"> </a><font size=2  face="Verdana, Arial, Helvetica, sans-serif">Normally a value can be loaded into the instruction data value by a variety of different prefix sequences. It is important to use the shortest possible sequence as this enhances both code compaction and execution speed. The best method of optimizing object code so as to minimize the number of prefix instructions needed is shown below. </font>
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<h3>
  <a name="1051081"> </a><font color="#003366"  face="Verdana, Arial, Helvetica, sans-serif">C.1.1 	 Prefixing a constant</font>
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<p>
  <a name="1051082"> </a><font size=2  face="Verdana, Arial, Helvetica, sans-serif">The algorithm to generate a constant instruction data value <em>e</em> for a function <em>op</em> is described by the following recursive function. </font>
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<dl>  <dl>
    <dt> <a name="1051083"> </a><font size=2  face="Verdana, Arial, Helvetica, sans-serif">prefix(<em>op</em>, <em>e</em>) =

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