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.

157 lines
7.2 KiB
HTML

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<!-- Copyright (C) 1988-2018 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 the
Invariant Sections being "Funding Free Software", the Front-Cover
Texts being (a) (see below), and with the Back-Cover Texts being (b)
(see below). A copy of the license is included in the section entitled
"GNU Free Documentation License".
(a) The FSF's Front-Cover Text is:
A GNU Manual
(b) The FSF's Back-Cover Text is:
You have freedom to copy and modify this GNU Manual, like GNU
software. Copies published by the Free Software Foundation raise
funds for GNU development. -->
<!-- Created by GNU Texinfo 6.4, http://www.gnu.org/software/texinfo/ -->
<head>
<title>ARC Function Attributes (Using the GNU Compiler Collection (GCC))</title>
<meta name="description" content="ARC Function Attributes (Using the GNU Compiler Collection (GCC))">
<meta name="keywords" content="ARC Function Attributes (Using the GNU Compiler Collection (GCC))">
<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="Option-Index.html#Option-Index" rel="index" title="Option Index">
<link href="index.html#SEC_Contents" rel="contents" title="Table of Contents">
<link href="Function-Attributes.html#Function-Attributes" rel="up" title="Function Attributes">
<link href="ARM-Function-Attributes.html#ARM-Function-Attributes" rel="next" title="ARM Function Attributes">
<link href="AArch64-Function-Attributes.html#AArch64-Function-Attributes" rel="prev" title="AArch64 Function Attributes">
<style type="text/css">
<!--
a.summary-letter {text-decoration: none}
blockquote.indentedblock {margin-right: 0em}
blockquote.smallindentedblock {margin-right: 0em; font-size: smaller}
blockquote.smallquotation {font-size: smaller}
div.display {margin-left: 3.2em}
div.example {margin-left: 3.2em}
div.lisp {margin-left: 3.2em}
div.smalldisplay {margin-left: 3.2em}
div.smallexample {margin-left: 3.2em}
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.nolinebreak {white-space: nowrap}
span.roman {font-family: initial; font-weight: normal}
span.sansserif {font-family: sans-serif; font-weight: normal}
ul.no-bullet {list-style: none}
-->
</style>
</head>
<body lang="en">
<a name="ARC-Function-Attributes"></a>
<div class="header">
<p>
Next: <a href="ARM-Function-Attributes.html#ARM-Function-Attributes" accesskey="n" rel="next">ARM Function Attributes</a>, Previous: <a href="AArch64-Function-Attributes.html#AArch64-Function-Attributes" accesskey="p" rel="prev">AArch64 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>
</div>
<hr>
<a name="ARC-Function-Attributes-1"></a>
<h4 class="subsection">6.31.3 ARC Function Attributes</h4>
<p>These function attributes are supported by the ARC back end:
</p>
<dl compact="compact">
<dt><code>interrupt</code></dt>
<dd><a name="index-interrupt-function-attribute_002c-ARC"></a>
<p>Use this attribute to indicate
that the specified function is an interrupt handler. The compiler generates
function entry and exit sequences suitable for use in an interrupt handler
when this attribute is present.
</p>
<p>On the ARC, you must specify the kind of interrupt to be handled
in a parameter to the interrupt attribute like this:
</p>
<div class="smallexample">
<pre class="smallexample">void f () __attribute__ ((interrupt (&quot;ilink1&quot;)));
</pre></div>
<p>Permissible values for this parameter are: <code>ilink1</code><!-- /@w --> and
<code>ilink2</code><!-- /@w -->.
</p>
</dd>
<dt><code>long_call</code></dt>
<dt><code>medium_call</code></dt>
<dt><code>short_call</code></dt>
<dd><a name="index-long_005fcall-function-attribute_002c-ARC"></a>
<a name="index-medium_005fcall-function-attribute_002c-ARC"></a>
<a name="index-short_005fcall-function-attribute_002c-ARC"></a>
<a name="index-indirect-calls_002c-ARC"></a>
<p>These attributes specify how a particular function is called.
These attributes override the
<samp>-mlong-calls</samp> and <samp>-mmedium-calls</samp> (see <a href="ARC-Options.html#ARC-Options">ARC Options</a>)
command-line switches and <code>#pragma long_calls</code> settings.
</p>
<p>For ARC, a function marked with the <code>long_call</code> attribute is
always called using register-indirect jump-and-link instructions,
thereby enabling the called function to be placed anywhere within the
32-bit address space. A function marked with the <code>medium_call</code>
attribute will always be close enough to be called with an unconditional
branch-and-link instruction, which has a 25-bit offset from
the call site. A function marked with the <code>short_call</code>
attribute will always be close enough to be called with a conditional
branch-and-link instruction, which has a 21-bit offset from
the call site.
</p>
</dd>
<dt><code>jli_always</code></dt>
<dd><a name="index-jli_005falways-function-attribute_002c-ARC"></a>
<p>Forces a particular function to be called using <code>jli</code>
instruction. The <code>jli</code> instruction makes use of a table stored
into <code>.jlitab</code> section, which holds the location of the functions
which are addressed using this instruction.
</p>
</dd>
<dt><code>jli_fixed</code></dt>
<dd><a name="index-jli_005ffixed-function-attribute_002c-ARC"></a>
<p>Identical like the above one, but the location of the function in the
<code>jli</code> table is known and given as an attribute parameter.
</p>
</dd>
<dt><code>secure_call</code></dt>
<dd><a name="index-secure_005fcall-function-attribute_002c-ARC"></a>
<p>This attribute allows one to mark secure-code functions that are
callable from normal mode. The location of the secure call function
into the <code>sjli</code> table needs to be passed as argument.
</p>
</dd>
</dl>
<hr>
<div class="header">
<p>
Next: <a href="ARM-Function-Attributes.html#ARM-Function-Attributes" accesskey="n" rel="next">ARM Function Attributes</a>, Previous: <a href="AArch64-Function-Attributes.html#AArch64-Function-Attributes" accesskey="p" rel="prev">AArch64 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>
</div>
</body>
</html>