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<title>ARC-Chars (Using as)</title>

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<a name="ARC_002dChars"></a>
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<p>
Next: <a href="ARC_002dRegs.html#ARC_002dRegs" accesskey="n" rel="next">ARC-Regs</a>, Up: <a href="ARC-Syntax.html#ARC-Syntax" accesskey="u" rel="up">ARC Syntax</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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<hr>
<a name="Special-Characters-2"></a>
<h4 class="subsubsection">9.3.2.1 Special Characters</h4>

<dl compact="compact">
<dt><code>%</code></dt>
<dd><a name="index-register-name-prefix-character_002c-ARC"></a>
<a name="index-ARC-register-name-prefix-character"></a>
<p>A register name can optionally be prefixed by a &lsquo;<samp>%</samp>&rsquo; character.  So
register <code>%r0</code> is equivalent to <code>r0</code> in the assembly code.
</p>
</dd>
<dt><code>#</code></dt>
<dd><a name="index-line-comment-character_002c-ARC"></a>
<a name="index-ARC-line-comment-character"></a>
<p>The presence of a &lsquo;<samp>#</samp>&rsquo; character within a line (but not at the
start of a line) indicates the start of a comment that extends to the
end of the current line.
</p>
<p><em>Note:</em> if a line starts with a &lsquo;<samp>#</samp>&rsquo; character then it can
also be a logical line number directive (see <a href="Comments.html#Comments">Comments</a>) or a
preprocessor control command (see <a href="Preprocessing.html#Preprocessing">Preprocessing</a>).
</p>
</dd>
<dt><code>@</code></dt>
<dd><a name="index-symbol-prefix-character_002c-ARC"></a>
<a name="index-ARC-symbol-prefix-character"></a>
<p>Prefixing an operand with an &lsquo;<samp>@</samp>&rsquo; specifies that the operand is a
symbol and not a register.  This is how the assembler disambiguates
the use of an ARC register name as a symbol.  So the instruction
</p><div class="example">
<pre class="example">mov r0, @r0
</pre></div>
<p>moves the address of symbol <code>r0</code> into register <code>r0</code>.
</p>
</dd>
<dt><code>`</code></dt>
<dd><a name="index-line-separator_002c-ARC"></a>
<a name="index-statement-separator_002c-ARC"></a>
<a name="index-ARC-line-separator"></a>
<p>The &lsquo;<samp>`</samp>&rsquo; (backtick) character is used to separate statements on a
single line.
</p>
<a name="index-line"></a>
</dd>
<dt><code>-</code></dt>
<dd><a name="index-C-preprocessor-macro-separator_002c-ARC"></a>
<a name="index-ARC-C-preprocessor-macro-separator"></a>
<p>Used as a separator to obtain a sequence of commands from a C
preprocessor macro.
</p>
</dd>
</dl>


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