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<title>Using as: Nios II Relocations</title>
 
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<p>
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<hr>
<a name="Nios-II-Machine-Relocations"></a>
<h4 class="subsection">9.31.3 Nios II Machine Relocations</h4>
 
<a name="index-machine-relocations_002c-Nios-II"></a>
<a name="index-Nios-II-machine-relocations"></a>
 
<dl compact="compact">
<dd><a name="index-hiadj-directive_002c-Nios-II"></a>
</dd>
<dt><code>%hiadj(<var>expression</var>)</code></dt>
<dd><p>Extract the upper 16 bits of <var>expression</var> and add 
one if the 15th bit is set. 
</p>
<p>The value of <code>%hiadj(<var>expression</var>)</code> is:
</p><div class="smallexample">
<pre class="smallexample">((<var>expression</var> &gt;&gt; 16) &amp; 0xffff) + ((<var>expression</var> &gt;&gt; 15) &amp; 0x01)
</pre></div>
 
<p>The <code>%hiadj</code> relocation is intended to be used with
the <code>addi</code>, <code>ld</code> or <code>st</code> instructions
along with a <code>%lo</code>, in order to load a 32-bit constant.
</p>
<div class="smallexample">
<pre class="smallexample">movhi r2, %hiadj(symbol)
addi r2, r2, %lo(symbol)
</pre></div>
 
<a name="index-hi-directive_002c-Nios-II"></a>
</dd>
<dt><code>%hi(<var>expression</var>)</code></dt>
<dd><p>Extract the upper 16 bits of <var>expression</var>.
</p>
<a name="index-lo-directive_002c-Nios-II"></a>
</dd>
<dt><code>%lo(<var>expression</var>)</code></dt>
<dd><p>Extract the lower 16 bits of <var>expression</var>.
</p>
<a name="index-gprel-directive_002c-Nios-II"></a>
</dd>
<dt><code>%gprel(<var>expression</var>)</code></dt>
<dd><p>Subtract the value of the symbol <code>_gp</code> from
<var>expression</var>. 
</p>
<p>The intention of the <code>%gprel</code> relocation is
to have a fast small area of memory which only
takes a 16-bit immediate to access.
</p>
<div class="smallexample">
<pre class="smallexample">    .section .sdata
fastint:
    .int 123
    .section .text
    ldw r4, %gprel(fastint)(gp)
</pre></div>
 
<a name="index-call-directive_002c-Nios-II"></a>
<a name="index-call_005flo-directive_002c-Nios-II"></a>
<a name="index-call_005fhiadj-directive_002c-Nios-II"></a>
<a name="index-got-directive_002c-Nios-II"></a>
<a name="index-got_005flo-directive_002c-Nios-II"></a>
<a name="index-got_005fhiadj-directive_002c-Nios-II"></a>
<a name="index-gotoff-directive_002c-Nios-II"></a>
<a name="index-gotoff_005flo-directive_002c-Nios-II"></a>
<a name="index-gotoff_005fhiadj-directive_002c-Nios-II"></a>
<a name="index-tls_005fgd-directive_002c-Nios-II"></a>
<a name="index-tls_005fie-directive_002c-Nios-II"></a>
<a name="index-tls_005fle-directive_002c-Nios-II"></a>
<a name="index-tls_005fldm-directive_002c-Nios-II"></a>
<a name="index-tls_005fldo-directive_002c-Nios-II"></a>
</dd>
<dt><code>%call(<var>expression</var>)</code></dt>
<dt><code>%call_lo(<var>expression</var>)</code></dt>
<dt><code>%call_hiadj(<var>expression</var>)</code></dt>
<dt><code>%got(<var>expression</var>)</code></dt>
<dt><code>%got_lo(<var>expression</var>)</code></dt>
<dt><code>%got_hiadj(<var>expression</var>)</code></dt>
<dt><code>%gotoff(<var>expression</var>)</code></dt>
<dt><code>%gotoff_lo(<var>expression</var>)</code></dt>
<dt><code>%gotoff_hiadj(<var>expression</var>)</code></dt>
<dt><code>%tls_gd(<var>expression</var>)</code></dt>
<dt><code>%tls_ie(<var>expression</var>)</code></dt>
<dt><code>%tls_le(<var>expression</var>)</code></dt>
<dt><code>%tls_ldm(<var>expression</var>)</code></dt>
<dt><code>%tls_ldo(<var>expression</var>)</code></dt>
<dd>
<p>These relocations support the ABI for Linux Systems documented in the
<cite>Nios II Processor Reference Handbook</cite>.
</p></dd>
</dl>
 
 
 
 
 
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