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<title>Using as: M68HC11-Directives</title>

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<a name="M68HC11_002dDirectives"></a>
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<p>
Next: <a href="M68HC11_002dFloat.html#M68HC11_002dFloat" accesskey="n" rel="next">M68HC11-Float</a>, Previous: <a href="M68HC11_002dModifiers.html#M68HC11_002dModifiers" accesskey="p" rel="prev">M68HC11-Modifiers</a>, Up: <a href="M68HC11_002dDependent.html#M68HC11_002dDependent" accesskey="u" rel="up">M68HC11-Dependent</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="Assembler-Directives-2"></a>
<h4 class="subsection">9.24.4 Assembler Directives</h4>

<a name="index-assembler-directives_002c-M68HC11"></a>
<a name="index-assembler-directives_002c-M68HC12"></a>
<a name="index-M68HC11-assembler-directives"></a>
<a name="index-M68HC12-assembler-directives"></a>

<p>The 68HC11 and 68HC12 version of <code>as</code> have the following
specific assembler directives:
</p>
<dl compact="compact">
<dt><code>.relax</code></dt>
<dd><a name="index-assembler-directive-_002erelax_002c-M68HC11"></a>
<a name="index-M68HC11-assembler-directive-_002erelax"></a>
<p>The relax directive is used by the &lsquo;<samp>GNU Compiler</samp>&rsquo; to emit a specific
relocation to mark a group of instructions for linker relaxation.
The sequence of instructions within the group must be known to the linker
so that relaxation can be performed.
</p>
</dd>
<dt><code>.mode [mshort|mlong|mshort-double|mlong-double]</code></dt>
<dd><a name="index-assembler-directive-_002emode_002c-M68HC11"></a>
<a name="index-M68HC11-assembler-directive-_002emode"></a>
<p>This directive specifies the ABI.  It overrides the &lsquo;<samp>-mshort</samp>&rsquo;,
&lsquo;<samp>-mlong</samp>&rsquo;, &lsquo;<samp>-mshort-double</samp>&rsquo; and &lsquo;<samp>-mlong-double</samp>&rsquo; options.
</p>
</dd>
<dt><code>.far <var>symbol</var></code></dt>
<dd><a name="index-assembler-directive-_002efar_002c-M68HC11"></a>
<a name="index-M68HC11-assembler-directive-_002efar"></a>
<p>This directive marks the symbol as a &lsquo;<samp>far</samp>&rsquo; symbol meaning that it
uses a &lsquo;<samp>call/rtc</samp>&rsquo; calling convention as opposed to &lsquo;<samp>jsr/rts</samp>&rsquo;.
During a final link, the linker will identify references to the &lsquo;<samp>far</samp>&rsquo;
symbol and will verify the proper calling convention.
</p>
</dd>
<dt><code>.interrupt <var>symbol</var></code></dt>
<dd><a name="index-assembler-directive-_002einterrupt_002c-M68HC11"></a>
<a name="index-M68HC11-assembler-directive-_002einterrupt"></a>
<p>This directive marks the symbol as an interrupt entry point.
This information is then used by the debugger to correctly unwind the
frame across interrupts.
</p>
</dd>
<dt><code>.xrefb <var>symbol</var></code></dt>
<dd><a name="index-assembler-directive-_002exrefb_002c-M68HC11"></a>
<a name="index-M68HC11-assembler-directive-_002exrefb"></a>
<p>This directive is defined for compatibility with the
&lsquo;<samp>Specification for Motorola 8 and 16-Bit Assembly Language Input
Standard</samp>&rsquo; and is ignored.
</p>
</dd>
</dl>


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