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<a name="Blackfin-Function-Attributes"></a>
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<p>
Next: <a href="CR16-Function-Attributes.html#CR16-Function-Attributes" accesskey="n" rel="next">CR16 Function Attributes</a>, Previous: <a href="AVR-Function-Attributes.html#AVR-Function-Attributes" accesskey="p" rel="prev">AVR 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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<hr>
<a name="Blackfin-Function-Attributes-1"></a>
<h4 class="subsection">6.31.6 Blackfin Function Attributes</h4>
<p>These function attributes are supported by the Blackfin back end:
</p>
<dl compact="compact">
<dt><code>exception_handler</code></dt>
<dd><a name="index-exception_005fhandler-function-attribute"></a>
<a name="index-exception-handler-functions_002c-Blackfin"></a>
<p>Use this attribute on the Blackfin to indicate that the specified function
is an exception handler. The compiler generates function entry and
exit sequences suitable for use in an exception handler when this
attribute is present.
</p>
</dd>
<dt><code>interrupt_handler</code></dt>
<dd><a name="index-interrupt_005fhandler-function-attribute_002c-Blackfin"></a>
<p>Use this attribute to
indicate that the specified function is an interrupt handler. The compiler
generates function entry and exit sequences suitable for use in an
interrupt handler when this attribute is present.
</p>
</dd>
<dt><code>kspisusp</code></dt>
<dd><a name="index-kspisusp-function-attribute_002c-Blackfin"></a>
<a name="index-User-stack-pointer-in-interrupts-on-the-Blackfin"></a>
<p>When used together with <code>interrupt_handler</code>, <code>exception_handler</code>
or <code>nmi_handler</code>, code is generated to load the stack pointer
from the USP register in the function prologue.
</p>
</dd>
<dt><code>l1_text</code></dt>
<dd><a name="index-l1_005ftext-function-attribute_002c-Blackfin"></a>
<p>This attribute specifies a function to be placed into L1 Instruction
SRAM. The function is put into a specific section named <code>.l1.text</code>.
With <samp>-mfdpic</samp>, function calls with a such function as the callee
or caller uses inlined PLT.
</p>
</dd>
<dt><code>l2</code></dt>
<dd><a name="index-l2-function-attribute_002c-Blackfin"></a>
<p>This attribute specifies a function to be placed into L2
SRAM. The function is put into a specific section named
<code>.l2.text</code>. With <samp>-mfdpic</samp>, callers of such functions use
an inlined PLT.
</p>
</dd>
<dt><code>longcall</code></dt>
<dt><code>shortcall</code></dt>
<dd><a name="index-indirect-calls_002c-Blackfin"></a>
<a name="index-longcall-function-attribute_002c-Blackfin"></a>
<a name="index-shortcall-function-attribute_002c-Blackfin"></a>
<p>The <code>longcall</code> attribute
indicates that the function might be far away from the call site and
require a different (more expensive) calling sequence. The
<code>shortcall</code> attribute indicates that the function is always close
enough for the shorter calling sequence to be used. These attributes
override the <samp>-mlongcall</samp> switch.
</p>
</dd>
<dt><code>nesting</code></dt>
<dd><a name="index-nesting-function-attribute_002c-Blackfin"></a>
<a name="index-Allow-nesting-in-an-interrupt-handler-on-the-Blackfin-processor"></a>
<p>Use this attribute together with <code>interrupt_handler</code>,
<code>exception_handler</code> or <code>nmi_handler</code> to indicate that the function
entry code should enable nested interrupts or exceptions.
</p>
</dd>
<dt><code>nmi_handler</code></dt>
<dd><a name="index-nmi_005fhandler-function-attribute_002c-Blackfin"></a>
<a name="index-NMI-handler-functions-on-the-Blackfin-processor"></a>
<p>Use this attribute on the Blackfin to indicate that the specified function
is an NMI handler. The compiler generates function entry and
exit sequences suitable for use in an NMI handler when this
attribute is present.
</p>
</dd>
<dt><code>saveall</code></dt>
<dd><a name="index-saveall-function-attribute_002c-Blackfin"></a>
<a name="index-save-all-registers-on-the-Blackfin"></a>
<p>Use this attribute to indicate that
all registers except the stack pointer should be saved in the prologue
regardless of whether they are used or not.
</p></dd>
</dl>
<hr>
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<p>
Next: <a href="CR16-Function-Attributes.html#CR16-Function-Attributes" accesskey="n" rel="next">CR16 Function Attributes</a>, Previous: <a href="AVR-Function-Attributes.html#AVR-Function-Attributes" accesskey="p" rel="prev">AVR 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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