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<a name="MicroBlaze-Function-Attributes"></a>
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Next: <a href="Microsoft-Windows-Function-Attributes.html#Microsoft-Windows-Function-Attributes" accesskey="n" rel="next">Microsoft Windows Function Attributes</a>, Previous: <a href="MeP-Function-Attributes.html#MeP-Function-Attributes" accesskey="p" rel="prev">MeP Function Attributes</a>, Up: <a href="Function-Attributes.html#Function-Attributes" accesskey="u" rel="up">Function Attributes</a> &nbsp; [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Option-Index.html#Option-Index" title="Index" rel="index">Index</a>]</p>
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<a name="MicroBlaze-Function-Attributes-1"></a>
<h4 class="subsection">6.31.16 MicroBlaze Function Attributes</h4>
<p>These function attributes are supported on MicroBlaze targets:
</p>
<dl compact="compact">
<dt><code>save_volatiles</code></dt>
<dd><a name="index-save_005fvolatiles-function-attribute_002c-MicroBlaze"></a>
<p>Use this attribute to indicate that the function is
an interrupt handler. All volatile registers (in addition to non-volatile
registers) are saved in the function prologue. If the function is a leaf
function, only volatiles used by the function are saved. A normal function
return is generated instead of a return from interrupt.
</p>
</dd>
<dt><code>break_handler</code></dt>
<dd><a name="index-break_005fhandler-function-attribute_002c-MicroBlaze"></a>
<a name="index-break-handler-functions"></a>
<p>Use this attribute to indicate that
the specified function is a break handler. The compiler generates function
entry and exit sequences suitable for use in an break handler when this
attribute is present. The return from <code>break_handler</code> is done through
the <code>rtbd</code> instead of <code>rtsd</code>.
</p>
<div class="smallexample">
<pre class="smallexample">void f () __attribute__ ((break_handler));
</pre></div>
</dd>
<dt><code>interrupt_handler</code></dt>
<dt><code>fast_interrupt</code></dt>
<dd><a name="index-interrupt_005fhandler-function-attribute_002c-MicroBlaze"></a>
<a name="index-fast_005finterrupt-function-attribute_002c-MicroBlaze"></a>
<p>These attributes indicate that the specified function is an interrupt
handler. Use the <code>fast_interrupt</code> attribute to indicate handlers
used in low-latency interrupt mode, and <code>interrupt_handler</code> for
interrupts that do not use low-latency handlers. In both cases, GCC
emits appropriate prologue code and generates a return from the handler
using <code>rtid</code> instead of <code>rtsd</code>.
</p></dd>
</dl>
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