You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
90 lines
6.0 KiB
HTML
90 lines
6.0 KiB
HTML
<html lang="en">
|
|
<head>
|
|
<title>Nios II Relocations - Using as</title>
|
|
<meta http-equiv="Content-Type" content="text/html">
|
|
<meta name="description" content="Using as">
|
|
<meta name="generator" content="makeinfo 4.13">
|
|
<link title="Top" rel="start" href="index.html#Top">
|
|
<link rel="up" href="NiosII_002dDependent.html#NiosII_002dDependent" title="NiosII-Dependent">
|
|
<link rel="prev" href="Nios-II-Syntax.html#Nios-II-Syntax" title="Nios II Syntax">
|
|
<link rel="next" href="Nios-II-Directives.html#Nios-II-Directives" title="Nios II Directives">
|
|
<link href="http://www.gnu.org/software/texinfo/" rel="generator-home" title="Texinfo Homepage">
|
|
<!--
|
|
This file documents the GNU Assembler "as".
|
|
|
|
Copyright (C) 1991-2015 Free Software Foundation, Inc.
|
|
|
|
Permission is granted to copy, distribute and/or modify this document
|
|
under the terms of the GNU Free Documentation License, Version 1.3
|
|
or any later version published by the Free Software Foundation;
|
|
with no Invariant Sections, with no Front-Cover Texts, and with no
|
|
Back-Cover Texts. A copy of the license is included in the
|
|
section entitled ``GNU Free Documentation License''.
|
|
|
|
-->
|
|
<meta http-equiv="Content-Style-Type" content="text/css">
|
|
<style type="text/css"><!--
|
|
pre.display { font-family:inherit }
|
|
pre.format { font-family:inherit }
|
|
pre.smalldisplay { font-family:inherit; font-size:smaller }
|
|
pre.smallformat { font-family:inherit; font-size:smaller }
|
|
pre.smallexample { font-size:smaller }
|
|
pre.smalllisp { font-size:smaller }
|
|
span.sc { font-variant:small-caps }
|
|
span.roman { font-family:serif; font-weight:normal; }
|
|
span.sansserif { font-family:sans-serif; font-weight:normal; }
|
|
--></style>
|
|
</head>
|
|
<body>
|
|
<div class="node">
|
|
<a name="Nios-II-Relocations"></a>
|
|
<p>
|
|
Next: <a rel="next" accesskey="n" href="Nios-II-Directives.html#Nios-II-Directives">Nios II Directives</a>,
|
|
Previous: <a rel="previous" accesskey="p" href="Nios-II-Syntax.html#Nios-II-Syntax">Nios II Syntax</a>,
|
|
Up: <a rel="up" accesskey="u" href="NiosII_002dDependent.html#NiosII_002dDependent">NiosII-Dependent</a>
|
|
<hr>
|
|
</div>
|
|
|
|
<h4 class="subsection">9.31.3 Nios II Machine Relocations</h4>
|
|
|
|
<p><a name="index-machine-relocations_002c-Nios-II-1676"></a><a name="index-Nios-II-machine-relocations-1677"></a>
|
|
|
|
<a name="index-g_t_0040code_007bhiadj_007d-directive_002c-Nios-II-1678"></a>
|
|
<dl><dt><code>%hiadj(</code><var>expression</var><code>)</code><dd>Extract the upper 16 bits of <var>expression</var> and add
|
|
one if the 15th bit is set.
|
|
|
|
<p>The value of <code>%hiadj(</code><var>expression</var><code>)</code> is:
|
|
<pre class="smallexample"> ((<var>expression</var> >> 16) & 0xffff) + ((<var>expression</var> >> 15) & 0x01)
|
|
</pre>
|
|
<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.
|
|
|
|
<pre class="smallexample"> movhi r2, %hiadj(symbol)
|
|
addi r2, r2, %lo(symbol)
|
|
</pre>
|
|
<p><a name="index-g_t_0040code_007bhi_007d-directive_002c-Nios-II-1679"></a><br><dt><code>%hi(</code><var>expression</var><code>)</code><dd>Extract the upper 16 bits of <var>expression</var>.
|
|
|
|
<p><a name="index-g_t_0040code_007blo_007d-directive_002c-Nios-II-1680"></a><br><dt><code>%lo(</code><var>expression</var><code>)</code><dd>Extract the lower 16 bits of <var>expression</var>.
|
|
|
|
<p><a name="index-g_t_0040code_007bgprel_007d-directive_002c-Nios-II-1681"></a><br><dt><code>%gprel(</code><var>expression</var><code>)</code><dd>Subtract the value of the symbol <code>_gp</code> from
|
|
<var>expression</var>.
|
|
|
|
<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.
|
|
|
|
<pre class="smallexample"> .section .sdata
|
|
fastint:
|
|
.int 123
|
|
.section .text
|
|
ldw r4, %gprel(fastint)(gp)
|
|
</pre>
|
|
<p><a name="index-g_t_0040code_007bcall_007d-directive_002c-Nios-II-1682"></a><a name="index-g_t_0040code_007bcall_005flo_007d-directive_002c-Nios-II-1683"></a><a name="index-g_t_0040code_007bcall_005fhiadj_007d-directive_002c-Nios-II-1684"></a><a name="index-g_t_0040code_007bgot_007d-directive_002c-Nios-II-1685"></a><a name="index-g_t_0040code_007bgot_005flo_007d-directive_002c-Nios-II-1686"></a><a name="index-g_t_0040code_007bgot_005fhiadj_007d-directive_002c-Nios-II-1687"></a><a name="index-g_t_0040code_007bgotoff_007d-directive_002c-Nios-II-1688"></a><a name="index-g_t_0040code_007bgotoff_005flo_007d-directive_002c-Nios-II-1689"></a><a name="index-g_t_0040code_007bgotoff_005fhiadj_007d-directive_002c-Nios-II-1690"></a><a name="index-g_t_0040code_007btls_005fgd_007d-directive_002c-Nios-II-1691"></a><a name="index-g_t_0040code_007btls_005fie_007d-directive_002c-Nios-II-1692"></a><a name="index-g_t_0040code_007btls_005fle_007d-directive_002c-Nios-II-1693"></a><a name="index-g_t_0040code_007btls_005fldm_007d-directive_002c-Nios-II-1694"></a><a name="index-g_t_0040code_007btls_005fldo_007d-directive_002c-Nios-II-1695"></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>
|
|
These relocations support the ABI for Linux Systems documented in the
|
|
<cite>Nios II Processor Reference Handbook</cite>.
|
|
</dl>
|
|
|
|
</body></html>
|
|
|