blob: 50d92722114ed910e3f2175527c42de29adb37bd [file] [log] [blame]
<!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) 1991-2013 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: s390 Mnemonics</title>
<meta name="description" content="Using as: s390 Mnemonics">
<meta name="keywords" content="Using as: s390 Mnemonics">
<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-Operands.html#s390-Operands" rel="next" title="s390 Operands">
<link href="s390-Register.html#s390-Register" rel="prev" title="s390 Register">
<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="s390-Mnemonics"></a>
<div class="header">
<p>
Next: <a href="s390-Operands.html#s390-Operands" accesskey="n" rel="next">s390 Operands</a>, Previous: <a href="s390-Register.html#s390-Register" accesskey="p" rel="prev">s390 Register</a>, Up: <a href="s390-Syntax.html#s390-Syntax" accesskey="u" rel="up">s390 Syntax</a> &nbsp; [<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-Mnemonics"></a>
<h4 class="subsubsection">9.37.3.2 Instruction Mnemonics</h4>
<a name="index-instruction-mnemonics_002c-s390"></a>
<a name="index-s390-instruction-mnemonics"></a>
<p>All instructions documented in the Principles of Operation are supported
with the mnemonic and order of operands as described.
The instruction mnemonic identifies the instruction format
(<a href="s390-Formats.html#s390-Formats">s390 Formats</a>) and the specific operation code for the instruction.
For example, the &lsquo;<samp>lr</samp>&rsquo; mnemonic denotes the instruction format &lsquo;<samp>RR</samp>&rsquo;
with the operation code &lsquo;<samp>0x18</samp>&rsquo;.
</p>
<p>The definition of the various mnemonics follows a scheme, where the first
character usually hint at the type of the instruction:
</p>
<div class="display">
<table>
<tr><td><pre class="display">a</pre></td><td><pre class="display">add instruction, for example &lsquo;<samp>al</samp>&rsquo; for add logical 32-bit</pre></td></tr>
<tr><td><pre class="display">b</pre></td><td><pre class="display">branch instruction, for example &lsquo;<samp>bc</samp>&rsquo; for branch on condition</pre></td></tr>
<tr><td><pre class="display">c</pre></td><td><pre class="display">compare or convert instruction, for example &lsquo;<samp>cr</samp>&rsquo; for compare
register 32-bit</pre></td></tr>
<tr><td><pre class="display">d</pre></td><td><pre class="display">divide instruction, for example &lsquo;<samp>dlr</samp>&rsquo; devide logical register
64-bit to 32-bit</pre></td></tr>
<tr><td><pre class="display">i</pre></td><td><pre class="display">insert instruction, for example &lsquo;<samp>ic</samp>&rsquo; insert character</pre></td></tr>
<tr><td><pre class="display">l</pre></td><td><pre class="display">load instruction, for example &lsquo;<samp>ltr</samp>&rsquo; load and test register</pre></td></tr>
<tr><td><pre class="display">mv</pre></td><td><pre class="display">move instruction, for example &lsquo;<samp>mvc</samp>&rsquo; move character</pre></td></tr>
<tr><td><pre class="display">m</pre></td><td><pre class="display">multiply instruction, for example &lsquo;<samp>mh</samp>&rsquo; multiply halfword</pre></td></tr>
<tr><td><pre class="display">n</pre></td><td><pre class="display">and instruction, for example &lsquo;<samp>ni</samp>&rsquo; and immediate</pre></td></tr>
<tr><td><pre class="display">o</pre></td><td><pre class="display">or instruction, for example &lsquo;<samp>oc</samp>&rsquo; or character</pre></td></tr>
<tr><td><pre class="display">sla, sll</pre></td><td><pre class="display">shift left single instruction</pre></td></tr>
<tr><td><pre class="display">sra, srl</pre></td><td><pre class="display">shift right single instruction</pre></td></tr>
<tr><td><pre class="display">st</pre></td><td><pre class="display">store instruction, for example &lsquo;<samp>stm</samp>&rsquo; store multiple</pre></td></tr>
<tr><td><pre class="display">s</pre></td><td><pre class="display">subtract instruction, for example &lsquo;<samp>slr</samp>&rsquo; subtract
logical 32-bit</pre></td></tr>
<tr><td><pre class="display">t</pre></td><td><pre class="display">test or translate instruction, of example &lsquo;<samp>tm</samp>&rsquo; test under mask</pre></td></tr>
<tr><td><pre class="display">x</pre></td><td><pre class="display">exclusive or instruction, for example &lsquo;<samp>xc</samp>&rsquo; exclusive or
character</pre></td></tr>
</table>
</div>
<p>Certain characters at the end of the mnemonic may describe a property
of the instruction:
</p>
<div class="display">
<table>
<tr><td><pre class="display">c</pre></td><td><pre class="display">the instruction uses a 8-bit character operand</pre></td></tr>
<tr><td><pre class="display">f</pre></td><td><pre class="display">the instruction extends a 32-bit operand to 64 bit</pre></td></tr>
<tr><td><pre class="display">g</pre></td><td><pre class="display">the operands are treated as 64-bit values</pre></td></tr>
<tr><td><pre class="display">h</pre></td><td><pre class="display">the operand uses a 16-bit halfword operand</pre></td></tr>
<tr><td><pre class="display">i</pre></td><td><pre class="display">the instruction uses an immediate operand</pre></td></tr>
<tr><td><pre class="display">l</pre></td><td><pre class="display">the instruction uses unsigned, logical operands</pre></td></tr>
<tr><td><pre class="display">m</pre></td><td><pre class="display">the instruction uses a mask or operates on multiple values</pre></td></tr>
<tr><td><pre class="display">r</pre></td><td><pre class="display">if r is the last character, the instruction operates on registers</pre></td></tr>
<tr><td><pre class="display">y</pre></td><td><pre class="display">the instruction uses 20-bit displacements</pre></td></tr>
</table>
</div>
<p>There are many exceptions to the scheme outlined in the above lists, in
particular for the priviledged instructions. For non-priviledged
instruction it works quite well, for example the instruction &lsquo;<samp>clgfr</samp>&rsquo;
c: compare instruction, l: unsigned operands, g: 64-bit operands,
f: 32- to 64-bit extension, r: register operands. The instruction compares
an 64-bit value in a register with the zero extended 32-bit value from
a second register.
For a complete list of all mnemonics see appendix B in the Principles
of Operation.
</p>
<hr>
<div class="header">
<p>
Next: <a href="s390-Operands.html#s390-Operands" accesskey="n" rel="next">s390 Operands</a>, Previous: <a href="s390-Register.html#s390-Register" accesskey="p" rel="prev">s390 Register</a>, Up: <a href="s390-Syntax.html#s390-Syntax" accesskey="u" rel="up">s390 Syntax</a> &nbsp; [<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>