219 lines
8.2 KiB
HTML
219 lines
8.2 KiB
HTML
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
|
|
<html>
|
|
<!-- This file documents the GNU Assembler "as".
|
|
|
|
Copyright (C) 1991-2016 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".
|
|
-->
|
|
<!-- Created by GNU Texinfo 5.2, http://www.gnu.org/software/texinfo/ -->
|
|
<head>
|
|
<title>Using as: AArch64 Directives</title>
|
|
|
|
<meta name="description" content="Using as: AArch64 Directives">
|
|
<meta name="keywords" content="Using as: AArch64 Directives">
|
|
<meta name="resource-type" content="document">
|
|
<meta name="distribution" content="global">
|
|
<meta name="Generator" content="makeinfo">
|
|
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
|
|
<link href="index.html#Top" rel="start" title="Top">
|
|
<link href="AS-Index.html#AS-Index" rel="index" title="AS Index">
|
|
<link href="index.html#SEC_Contents" rel="contents" title="Table of Contents">
|
|
<link href="AArch64_002dDependent.html#AArch64_002dDependent" rel="up" title="AArch64-Dependent">
|
|
<link href="AArch64-Opcodes.html#AArch64-Opcodes" rel="next" title="AArch64 Opcodes">
|
|
<link href="AArch64-Floating-Point.html#AArch64-Floating-Point" rel="prev" title="AArch64 Floating Point">
|
|
<style type="text/css">
|
|
<!--
|
|
a.summary-letter {text-decoration: none}
|
|
blockquote.smallquotation {font-size: smaller}
|
|
div.display {margin-left: 3.2em}
|
|
div.example {margin-left: 3.2em}
|
|
div.indentedblock {margin-left: 3.2em}
|
|
div.lisp {margin-left: 3.2em}
|
|
div.smalldisplay {margin-left: 3.2em}
|
|
div.smallexample {margin-left: 3.2em}
|
|
div.smallindentedblock {margin-left: 3.2em; font-size: smaller}
|
|
div.smalllisp {margin-left: 3.2em}
|
|
kbd {font-style:oblique}
|
|
pre.display {font-family: inherit}
|
|
pre.format {font-family: inherit}
|
|
pre.menu-comment {font-family: serif}
|
|
pre.menu-preformatted {font-family: serif}
|
|
pre.smalldisplay {font-family: inherit; font-size: smaller}
|
|
pre.smallexample {font-size: smaller}
|
|
pre.smallformat {font-family: inherit; font-size: smaller}
|
|
pre.smalllisp {font-size: smaller}
|
|
span.nocodebreak {white-space:nowrap}
|
|
span.nolinebreak {white-space:nowrap}
|
|
span.roman {font-family:serif; font-weight:normal}
|
|
span.sansserif {font-family:sans-serif; font-weight:normal}
|
|
ul.no-bullet {list-style: none}
|
|
-->
|
|
</style>
|
|
|
|
|
|
</head>
|
|
|
|
<body lang="en" bgcolor="#FFFFFF" text="#000000" link="#0000FF" vlink="#800080" alink="#FF0000">
|
|
<a name="AArch64-Directives"></a>
|
|
<div class="header">
|
|
<p>
|
|
Next: <a href="AArch64-Opcodes.html#AArch64-Opcodes" accesskey="n" rel="next">AArch64 Opcodes</a>, Previous: <a href="AArch64-Floating-Point.html#AArch64-Floating-Point" accesskey="p" rel="prev">AArch64 Floating Point</a>, Up: <a href="AArch64_002dDependent.html#AArch64_002dDependent" accesskey="u" rel="up">AArch64-Dependent</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="AS-Index.html#AS-Index" title="Index" rel="index">Index</a>]</p>
|
|
</div>
|
|
<hr>
|
|
<a name="AArch64-Machine-Directives"></a>
|
|
<h4 class="subsection">9.1.5 AArch64 Machine Directives</h4>
|
|
|
|
<a name="index-machine-directives_002c-AArch64"></a>
|
|
<a name="index-AArch64-machine-directives"></a>
|
|
<dl compact="compact">
|
|
<dd>
|
|
|
|
<a name="index-_002earch-directive_002c-AArch64"></a>
|
|
</dd>
|
|
<dt><code>.arch <var>name</var></code></dt>
|
|
<dd><p>Select the target architecture. Valid values for <var>name</var> are the same as
|
|
for the <samp>-march</samp> commandline option.
|
|
</p>
|
|
<p>Specifying <code>.arch</code> clears any previously selected architecture
|
|
extensions.
|
|
</p>
|
|
<a name="index-_002earch_005fextension-directive_002c-AArch64"></a>
|
|
</dd>
|
|
<dt><code>.arch_extension <var>name</var></code></dt>
|
|
<dd><p>Add or remove an architecture extension to the target architecture. Valid
|
|
values for <var>name</var> are the same as those accepted as architectural
|
|
extensions by the <samp>-mcpu</samp> commandline option.
|
|
</p>
|
|
<p><code>.arch_extension</code> may be used multiple times to add or remove extensions
|
|
incrementally to the architecture being compiled for.
|
|
</p>
|
|
|
|
<a name="index-_002ebss-directive_002c-AArch64"></a>
|
|
</dd>
|
|
<dt><code>.bss</code></dt>
|
|
<dd><p>This directive switches to the <code>.bss</code> section.
|
|
</p>
|
|
|
|
<a name="index-_002ecpu-directive_002c-AArch64"></a>
|
|
</dd>
|
|
<dt><code>.cpu <var>name</var></code></dt>
|
|
<dd><p>Set the target processor. Valid values for <var>name</var> are the same as
|
|
those accepted by the <samp>-mcpu=</samp> command line option.
|
|
</p>
|
|
|
|
<a name="index-_002edword-directive_002c-AArch64"></a>
|
|
</dd>
|
|
<dt><code>.dword <var>expressions</var></code></dt>
|
|
<dd><p>The <code>.dword</code> directive produces 64 bit values.
|
|
</p>
|
|
|
|
<a name="index-_002eeven-directive_002c-AArch64"></a>
|
|
</dd>
|
|
<dt><code>.even</code></dt>
|
|
<dd><p>The <code>.even</code> directive aligns the output on the next even byte
|
|
boundary.
|
|
</p>
|
|
|
|
<a name="index-_002einst-directive_002c-AArch64"></a>
|
|
</dd>
|
|
<dt><code>.inst <var>expressions</var></code></dt>
|
|
<dd><p>Inserts the expressions into the output as if they were instructions,
|
|
rather than data.
|
|
</p>
|
|
|
|
<a name="index-_002eltorg-directive_002c-AArch64"></a>
|
|
</dd>
|
|
<dt><code>.ltorg</code></dt>
|
|
<dd><p>This directive causes the current contents of the literal pool to be
|
|
dumped into the current section (which is assumed to be the .text
|
|
section) at the current location (aligned to a word boundary).
|
|
GAS maintains a separate literal pool for each section and each
|
|
sub-section. The <code>.ltorg</code> directive will only affect the literal
|
|
pool of the current section and sub-section. At the end of assembly
|
|
all remaining, un-empty literal pools will automatically be dumped.
|
|
</p>
|
|
<p>Note - older versions of GAS would dump the current literal
|
|
pool any time a section change occurred. This is no longer done, since
|
|
it prevents accurate control of the placement of literal pools.
|
|
</p>
|
|
|
|
|
|
|
|
<a name="index-_002epool-directive_002c-AArch64"></a>
|
|
</dd>
|
|
<dt><code>.pool</code></dt>
|
|
<dd><p>This is a synonym for .ltorg.
|
|
</p>
|
|
|
|
<a name="index-_002ereq-directive_002c-AArch64"></a>
|
|
</dd>
|
|
<dt><code><var>name</var> .req <var>register name</var></code></dt>
|
|
<dd><p>This creates an alias for <var>register name</var> called <var>name</var>. For
|
|
example:
|
|
</p>
|
|
<div class="smallexample">
|
|
<pre class="smallexample"> foo .req w0
|
|
</pre></div>
|
|
|
|
|
|
|
|
<a name="index-_002etlsdescadd-directive_002c-AArch64"></a>
|
|
</dd>
|
|
<dt><code><code>.tlsdescadd</code></code></dt>
|
|
<dd><p>Emits a TLSDESC_ADD reloc on the next instruction.
|
|
</p>
|
|
<a name="index-_002etlsdesccall-directive_002c-AArch64"></a>
|
|
</dd>
|
|
<dt><code><code>.tlsdesccall</code></code></dt>
|
|
<dd><p>Emits a TLSDESC_CALL reloc on the next instruction.
|
|
</p>
|
|
<a name="index-_002etlsdescldr-directive_002c-AArch64"></a>
|
|
</dd>
|
|
<dt><code><code>.tlsdescldr</code></code></dt>
|
|
<dd><p>Emits a TLSDESC_LDR reloc on the next instruction.
|
|
</p>
|
|
|
|
<a name="index-_002eunreq-directive_002c-AArch64"></a>
|
|
</dd>
|
|
<dt><code>.unreq <var>alias-name</var></code></dt>
|
|
<dd><p>This undefines a register alias which was previously defined using the
|
|
<code>req</code> directive. For example:
|
|
</p>
|
|
<div class="smallexample">
|
|
<pre class="smallexample"> foo .req w0
|
|
.unreq foo
|
|
</pre></div>
|
|
|
|
<p>An error occurs if the name is undefined. Note - this pseudo op can
|
|
be used to delete builtin in register name aliases (eg ’w0’). This
|
|
should only be done if it is really necessary.
|
|
</p>
|
|
|
|
|
|
<a name="index-_002exword-directive_002c-AArch64"></a>
|
|
</dd>
|
|
<dt><code>.xword <var>expressions</var></code></dt>
|
|
<dd><p>The <code>.xword</code> directive produces 64 bit values. This is the same
|
|
as the <code>.dword</code> directive.
|
|
</p>
|
|
|
|
</dd>
|
|
</dl>
|
|
|
|
<hr>
|
|
<div class="header">
|
|
<p>
|
|
Next: <a href="AArch64-Opcodes.html#AArch64-Opcodes" accesskey="n" rel="next">AArch64 Opcodes</a>, Previous: <a href="AArch64-Floating-Point.html#AArch64-Floating-Point" accesskey="p" rel="prev">AArch64 Floating Point</a>, Up: <a href="AArch64_002dDependent.html#AArch64_002dDependent" accesskey="u" rel="up">AArch64-Dependent</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="AS-Index.html#AS-Index" title="Index" rel="index">Index</a>]</p>
|
|
</div>
|
|
|
|
|
|
|
|
</body>
|
|
</html>
|