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.
160 lines
7.7 KiB
HTML
160 lines
7.7 KiB
HTML
4 years ago
|
<!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) 1991-2019 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 6.4, http://www.gnu.org/software/texinfo/ -->
|
||
|
|
<head>
|
||
|
|
<title>s390 Operand Modifier (Using as)</title>
|
||
|
|
|
||
|
|
<meta name="description" content="s390 Operand Modifier (Using as)">
|
||
|
|
<meta name="keywords" content="s390 Operand Modifier (Using as)">
|
||
|
|
<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="s390-Syntax.html#s390-Syntax" rel="up" title="s390 Syntax">
|
||
|
|
<link href="s390-Instruction-Marker.html#s390-Instruction-Marker" rel="next" title="s390 Instruction Marker">
|
||
|
|
<link href="s390-Aliases.html#s390-Aliases" rel="prev" title="s390 Aliases">
|
||
|
|
<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="s390-Operand-Modifier"></a>
|
||
|
|
<div class="header">
|
||
|
|
<p>
|
||
|
|
Next: <a href="s390-Instruction-Marker.html#s390-Instruction-Marker" accesskey="n" rel="next">s390 Instruction Marker</a>, Previous: <a href="s390-Aliases.html#s390-Aliases" accesskey="p" rel="prev">s390 Aliases</a>, Up: <a href="s390-Syntax.html#s390-Syntax" accesskey="u" rel="up">s390 Syntax</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="Instruction-Operand-Modifier"></a>
|
||
|
|
<h4 class="subsubsection">9.40.3.6 Instruction Operand Modifier</h4>
|
||
|
|
<a name="index-instruction-operand-modifier_002c-s390"></a>
|
||
|
|
<a name="index-s390-instruction-operand-modifier"></a>
|
||
|
|
|
||
|
|
<p>If a symbol modifier is attached to a symbol in an expression for an
|
||
|
|
instruction operand field, the symbol term is replaced with a reference
|
||
|
|
to an object in the global offset table (GOT) or the procedure linkage
|
||
|
|
table (PLT). The following expressions are allowed:
|
||
|
|
‘<samp>symbol@modifier + constant</samp>’,
|
||
|
|
‘<samp>symbol@modifier + label + constant</samp>’, and
|
||
|
|
‘<samp>symbol@modifier - label + constant</samp>’.
|
||
|
|
The term ‘<samp>symbol</samp>’ is the symbol that will be entered into the GOT or
|
||
|
|
PLT, ‘<samp>label</samp>’ is a local label, and ‘<samp>constant</samp>’ is an arbitrary
|
||
|
|
expression that the assembler can evaluate to a constant value.
|
||
|
|
</p>
|
||
|
|
<p>The term ‘<samp>(symbol + constant1)@modifier +/- label + constant2</samp>’
|
||
|
|
is also accepted but a warning message is printed and the term is
|
||
|
|
converted to ‘<samp>symbol@modifier +/- label + constant1 + constant2</samp>’.
|
||
|
|
</p>
|
||
|
|
<dl compact="compact">
|
||
|
|
<dt><code>@got</code></dt>
|
||
|
|
<dt><code>@got12</code></dt>
|
||
|
|
<dd><p>The @got modifier can be used for displacement fields, 16-bit immediate
|
||
|
|
fields and 32-bit pc-relative immediate fields. The @got12 modifier is
|
||
|
|
synonym to @got. The symbol is added to the GOT. For displacement
|
||
|
|
fields and 16-bit immediate fields the symbol term is replaced with
|
||
|
|
the offset from the start of the GOT to the GOT slot for the symbol.
|
||
|
|
For a 32-bit pc-relative field the pc-relative offset to the GOT
|
||
|
|
slot from the current instruction address is used.
|
||
|
|
</p></dd>
|
||
|
|
<dt><code>@gotent</code></dt>
|
||
|
|
<dd><p>The @gotent modifier can be used for 32-bit pc-relative immediate fields.
|
||
|
|
The symbol is added to the GOT and the symbol term is replaced with
|
||
|
|
the pc-relative offset from the current instruction to the GOT slot for the
|
||
|
|
symbol.
|
||
|
|
</p></dd>
|
||
|
|
<dt><code>@gotoff</code></dt>
|
||
|
|
<dd><p>The @gotoff modifier can be used for 16-bit immediate fields. The symbol
|
||
|
|
term is replaced with the offset from the start of the GOT to the
|
||
|
|
address of the symbol.
|
||
|
|
</p></dd>
|
||
|
|
<dt><code>@gotplt</code></dt>
|
||
|
|
<dd><p>The @gotplt modifier can be used for displacement fields, 16-bit immediate
|
||
|
|
fields, and 32-bit pc-relative immediate fields. A procedure linkage
|
||
|
|
table entry is generated for the symbol and a jump slot for the symbol
|
||
|
|
is added to the GOT. For displacement fields and 16-bit immediate
|
||
|
|
fields the symbol term is replaced with the offset from the start of the
|
||
|
|
GOT to the jump slot for the symbol. For a 32-bit pc-relative field
|
||
|
|
the pc-relative offset to the jump slot from the current instruction
|
||
|
|
address is used.
|
||
|
|
</p></dd>
|
||
|
|
<dt><code>@plt</code></dt>
|
||
|
|
<dd><p>The @plt modifier can be used for 16-bit and 32-bit pc-relative immediate
|
||
|
|
fields. A procedure linkage table entry is generated for the symbol.
|
||
|
|
The symbol term is replaced with the relative offset from the current
|
||
|
|
instruction to the PLT entry for the symbol.
|
||
|
|
</p></dd>
|
||
|
|
<dt><code>@pltoff</code></dt>
|
||
|
|
<dd><p>The @pltoff modifier can be used for 16-bit immediate fields. The symbol
|
||
|
|
term is replaced with the offset from the start of the PLT to the address
|
||
|
|
of the symbol.
|
||
|
|
</p></dd>
|
||
|
|
<dt><code>@gotntpoff</code></dt>
|
||
|
|
<dd><p>The @gotntpoff modifier can be used for displacement fields. The symbol
|
||
|
|
is added to the static TLS block and the negated offset to the symbol
|
||
|
|
in the static TLS block is added to the GOT. The symbol term is replaced
|
||
|
|
with the offset to the GOT slot from the start of the GOT.
|
||
|
|
</p></dd>
|
||
|
|
<dt><code>@indntpoff</code></dt>
|
||
|
|
<dd><p>The @indntpoff modifier can be used for 32-bit pc-relative immediate
|
||
|
|
fields. The symbol is added to the static TLS block and the negated offset
|
||
|
|
to the symbol in the static TLS block is added to the GOT. The symbol term
|
||
|
|
is replaced with the pc-relative offset to the GOT slot from the current
|
||
|
|
instruction address.
|
||
|
|
</p></dd>
|
||
|
|
</dl>
|
||
|
|
|
||
|
|
<p>For more information about the thread local storage modifiers
|
||
|
|
‘<samp>gotntpoff</samp>’ and ‘<samp>indntpoff</samp>’ see the ELF extension documentation
|
||
|
|
‘<samp>ELF Handling For Thread-Local Storage</samp>’.
|
||
|
|
</p>
|
||
|
|
<hr>
|
||
|
|
<div class="header">
|
||
|
|
<p>
|
||
|
|
Next: <a href="s390-Instruction-Marker.html#s390-Instruction-Marker" accesskey="n" rel="next">s390 Instruction Marker</a>, Previous: <a href="s390-Aliases.html#s390-Aliases" accesskey="p" rel="prev">s390 Aliases</a>, Up: <a href="s390-Syntax.html#s390-Syntax" accesskey="u" rel="up">s390 Syntax</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>
|