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<title>Using the GNU Compiler Collection (GCC): Nios II Function Attributes</title>

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<a name="Nios-II-Function-Attributes"></a>
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<p>
Next: <a href="Nvidia-PTX-Function-Attributes.html#Nvidia-PTX-Function-Attributes" accesskey="n" rel="next">Nvidia PTX Function Attributes</a>, Previous: <a href="NDS32-Function-Attributes.html#NDS32-Function-Attributes" accesskey="p" rel="prev">NDS32 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="Nios-II-Function-Attributes-1"></a>
<h4 class="subsection">6.31.21 Nios II Function Attributes</h4>

<p>These function attributes are supported by the Nios II back end:
</p>
<dl compact="compact">
<dt><code>target (<var>options</var>)</code></dt>
<dd><a name="index-target-function-attribute-2"></a>
<p>As discussed in <a href="Common-Function-Attributes.html#Common-Function-Attributes">Common Function Attributes</a>, this attribute 
allows specification of target-specific compilation options.
</p>
<p>When compiling for Nios II, the following options are allowed:
</p>
<dl compact="compact">
<dt>&lsquo;<samp>custom-<var>insn</var>=<var>N</var></samp>&rsquo;</dt>
<dt>&lsquo;<samp>no-custom-<var>insn</var></samp>&rsquo;</dt>
<dd><a name="index-target_0028_0022custom_002dinsn_003dN_0022_0029-function-attribute_002c-Nios-II"></a>
<a name="index-target_0028_0022no_002dcustom_002dinsn_0022_0029-function-attribute_002c-Nios-II"></a>
<p>Each &lsquo;<samp>custom-<var>insn</var>=<var>N</var></samp>&rsquo; attribute locally enables use of a
custom instruction with encoding <var>N</var> when generating code that uses 
<var>insn</var>.  Similarly, &lsquo;<samp>no-custom-<var>insn</var></samp>&rsquo; locally inhibits use of
the custom instruction <var>insn</var>.
These target attributes correspond to the
<samp>-mcustom-<var>insn</var>=<var>N</var></samp> and <samp>-mno-custom-<var>insn</var></samp>
command-line options, and support the same set of <var>insn</var> keywords.
See <a href="Nios-II-Options.html#Nios-II-Options">Nios II Options</a>, for more information.
</p>
</dd>
<dt>&lsquo;<samp>custom-fpu-cfg=<var>name</var></samp>&rsquo;</dt>
<dd><a name="index-target_0028_0022custom_002dfpu_002dcfg_003dname_0022_0029-function-attribute_002c-Nios-II"></a>
<p>This attribute corresponds to the <samp>-mcustom-fpu-cfg=<var>name</var></samp>
command-line option, to select a predefined set of custom instructions
named <var>name</var>.
See <a href="Nios-II-Options.html#Nios-II-Options">Nios II Options</a>, for more information.
</p></dd>
</dl>
</dd>
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