Labels.html 3.7 KB

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  60. Next: <a href="Setting-Symbols.html#Setting-Symbols" accesskey="n" rel="next">Setting Symbols</a>, Up: <a href="Symbols.html#Symbols" accesskey="u" rel="up">Symbols</a> &nbsp; [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="AS-Index.html#AS-Index" title="Index" rel="index">Index</a>]</p>
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  63. <a name="Labels-1"></a>
  64. <h3 class="section">5.1 Labels</h3>
  65. <a name="index-labels"></a>
  66. <p>A <em>label</em> is written as a symbol immediately followed by a colon
  67. &lsquo;<samp>:</samp>&rsquo;. The symbol then represents the current value of the
  68. active location counter, and is, for example, a suitable instruction
  69. operand. You are warned if you use the same symbol to represent two
  70. different locations: the first definition overrides any other
  71. definitions.
  72. </p>
  73. <p>On the HPPA, the usual form for a label need not be immediately followed by a
  74. colon, but instead must start in column zero. Only one label may be defined on
  75. a single line. To work around this, the HPPA version of <code>as</code> also
  76. provides a special directive <code>.label</code> for defining labels more flexibly.
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