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<title>Nios II Relocations - Using as</title>
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<link title="Top" rel="start" href="index.html#Top">
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<link rel="up" href="NiosII_002dDependent.html#NiosII_002dDependent" title="NiosII-Dependent">
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<link rel="prev" href="Nios-II-Syntax.html#Nios-II-Syntax" title="Nios II Syntax">
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<!--
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This file documents the GNU Assembler "as".
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Copyright (C) 1991-2019 Free Software Foundation, Inc.
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Permission is granted to copy, distribute and/or modify this document
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under the terms of the GNU Free Documentation License, Version 1.3
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or any later version published by the Free Software Foundation;
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with no Invariant Sections, with no Front-Cover Texts, and with no
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Back-Cover Texts. A copy of the license is included in the
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</head>
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<div class="node">
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<a name="Nios-II-Relocations"></a>
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<p>
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Next: <a rel="next" accesskey="n" href="Nios-II-Directives.html#Nios-II-Directives">Nios II Directives</a>,
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Previous: <a rel="previous" accesskey="p" href="Nios-II-Syntax.html#Nios-II-Syntax">Nios II Syntax</a>,
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Up: <a rel="up" accesskey="u" href="NiosII_002dDependent.html#NiosII_002dDependent">NiosII-Dependent</a>
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<hr>
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</div>
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<h4 class="subsection">9.31.3 Nios II Machine Relocations</h4>
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<p><a name="index-machine-relocations_002c-Nios-II-1784"></a><a name="index-Nios-II-machine-relocations-1785"></a>
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<a name="index-g_t_0040code_007bhiadj_007d-directive_002c-Nios-II-1786"></a>
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<dl><dt><code>%hiadj(</code><var>expression</var><code>)</code><dd>Extract the upper 16 bits of <var>expression</var> and add
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one if the 15th bit is set.
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<p>The value of <code>%hiadj(</code><var>expression</var><code>)</code> is:
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<pre class="smallexample"> ((<var>expression</var> >> 16) & 0xffff) + ((<var>expression</var> >> 15) & 0x01)
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</pre>
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<p>The <code>%hiadj</code> relocation is intended to be used with
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the <code>addi</code>, <code>ld</code> or <code>st</code> instructions
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along with a <code>%lo</code>, in order to load a 32-bit constant.
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<pre class="smallexample"> movhi r2, %hiadj(symbol)
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addi r2, r2, %lo(symbol)
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</pre>
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<p><a name="index-g_t_0040code_007bhi_007d-directive_002c-Nios-II-1787"></a><br><dt><code>%hi(</code><var>expression</var><code>)</code><dd>Extract the upper 16 bits of <var>expression</var>.
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<p><a name="index-g_t_0040code_007blo_007d-directive_002c-Nios-II-1788"></a><br><dt><code>%lo(</code><var>expression</var><code>)</code><dd>Extract the lower 16 bits of <var>expression</var>.
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<p><a name="index-g_t_0040code_007bgprel_007d-directive_002c-Nios-II-1789"></a><br><dt><code>%gprel(</code><var>expression</var><code>)</code><dd>Subtract the value of the symbol <code>_gp</code> from
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<var>expression</var>.
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<p>The intention of the <code>%gprel</code> relocation is
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to have a fast small area of memory which only
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takes a 16-bit immediate to access.
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<pre class="smallexample"> .section .sdata
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fastint:
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.int 123
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.section .text
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ldw r4, %gprel(fastint)(gp)
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</pre>
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<p><a name="index-g_t_0040code_007bcall_007d-directive_002c-Nios-II-1790"></a><a name="index-g_t_0040code_007bcall_005flo_007d-directive_002c-Nios-II-1791"></a><a name="index-g_t_0040code_007bcall_005fhiadj_007d-directive_002c-Nios-II-1792"></a><a name="index-g_t_0040code_007bgot_007d-directive_002c-Nios-II-1793"></a><a name="index-g_t_0040code_007bgot_005flo_007d-directive_002c-Nios-II-1794"></a><a name="index-g_t_0040code_007bgot_005fhiadj_007d-directive_002c-Nios-II-1795"></a><a name="index-g_t_0040code_007bgotoff_007d-directive_002c-Nios-II-1796"></a><a name="index-g_t_0040code_007bgotoff_005flo_007d-directive_002c-Nios-II-1797"></a><a name="index-g_t_0040code_007bgotoff_005fhiadj_007d-directive_002c-Nios-II-1798"></a><a name="index-g_t_0040code_007btls_005fgd_007d-directive_002c-Nios-II-1799"></a><a name="index-g_t_0040code_007btls_005fie_007d-directive_002c-Nios-II-1800"></a><a name="index-g_t_0040code_007btls_005fle_007d-directive_002c-Nios-II-1801"></a><a name="index-g_t_0040code_007btls_005fldm_007d-directive_002c-Nios-II-1802"></a><a name="index-g_t_0040code_007btls_005fldo_007d-directive_002c-Nios-II-1803"></a><br><dt><code>%call(</code><var>expression</var><code>)</code><br><dt><code>%call_lo(</code><var>expression</var><code>)</code><br><dt><code>%call_hiadj(</code><var>expression</var><code>)</code><dt><code>%got(</code><var>expression</var><code>)</code><dt><code>%got_lo(</code><var>expression</var><code>)</code><dt><code>%got_hiadj(</code><var>expression</var><code>)</code><dt><code>%gotoff(</code><var>expression</var><code>)</code><dt><code>%gotoff_lo(</code><var>expression</var><code>)</code><dt><code>%gotoff_hiadj(</code><var>expression</var><code>)</code><dt><code>%tls_gd(</code><var>expression</var><code>)</code><dt><code>%tls_ie(</code><var>expression</var><code>)</code><dt><code>%tls_le(</code><var>expression</var><code>)</code><dt><code>%tls_ldm(</code><var>expression</var><code>)</code><dt><code>%tls_ldo(</code><var>expression</var><code>)</code><dd>
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These relocations support the ABI for Linux Systems documented in the
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<cite>Nios II Processor Reference Handbook</cite>.
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</dl>
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