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A copy of the license is included in the 12section entitled "GNU Free Documentation License". 13 --> 14<!-- Created by GNU Texinfo 5.1, http://www.gnu.org/software/texinfo/ --> 15<head> 16<title>Using as: s390 Syntax</title> 17 18<meta name="description" content="Using as: s390 Syntax"> 19<meta name="keywords" content="Using as: s390 Syntax"> 20<meta name="resource-type" content="document"> 21<meta name="distribution" content="global"> 22<meta name="Generator" content="makeinfo"> 23<meta http-equiv="Content-Type" content="text/html; charset=utf-8"> 24<link href="index.html#Top" rel="start" title="Top"> 25<link href="AS-Index.html#AS-Index" rel="index" title="AS Index"> 26<link href="index.html#SEC_Contents" rel="contents" title="Table of Contents"> 27<link href="S_002f390_002dDependent.html#S_002f390_002dDependent" rel="up" title="S/390-Dependent"> 28<link href="s390-Register.html#s390-Register" rel="next" title="s390 Register"> 29<link href="s390-Characters.html#s390-Characters" rel="previous" title="s390 Characters"> 30<style type="text/css"> 31<!-- 32a.summary-letter {text-decoration: none} 33blockquote.smallquotation {font-size: smaller} 34div.display {margin-left: 3.2em} 35div.example {margin-left: 3.2em} 36div.indentedblock {margin-left: 3.2em} 37div.lisp {margin-left: 3.2em} 38div.smalldisplay {margin-left: 3.2em} 39div.smallexample {margin-left: 3.2em} 40div.smallindentedblock {margin-left: 3.2em; font-size: smaller} 41div.smalllisp {margin-left: 3.2em} 42kbd {font-style:oblique} 43pre.display {font-family: inherit} 44pre.format {font-family: inherit} 45pre.menu-comment {font-family: serif} 46pre.menu-preformatted {font-family: serif} 47pre.smalldisplay {font-family: inherit; font-size: smaller} 48pre.smallexample {font-size: smaller} 49pre.smallformat {font-family: inherit; font-size: smaller} 50pre.smalllisp {font-size: smaller} 51span.nocodebreak {white-space:nowrap} 52span.nolinebreak {white-space:nowrap} 53span.roman {font-family:serif; font-weight:normal} 54span.sansserif {font-family:sans-serif; font-weight:normal} 55ul.no-bullet {list-style: none} 56--> 57</style> 58 59 60</head> 61 62<body lang="en" bgcolor="#FFFFFF" text="#000000" link="#0000FF" vlink="#800080" alink="#FF0000"> 63<a name="s390-Syntax"></a> 64<div class="header"> 65<p> 66Next: <a href="s390-Directives.html#s390-Directives" accesskey="n" rel="next">s390 Directives</a>, Previous: <a href="s390-Characters.html#s390-Characters" accesskey="p" rel="previous">s390 Characters</a>, Up: <a href="S_002f390_002dDependent.html#S_002f390_002dDependent" accesskey="u" rel="up">S/390-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> 67</div> 68<hr> 69<a name="Instruction-syntax"></a> 70<h4 class="subsection">9.41.3 Instruction syntax</h4> 71<a name="index-instruction-syntax_002c-s390"></a> 72<a name="index-s390-instruction-syntax"></a> 73 74<p>The assembler syntax closely follows the syntax outlined in 75Enterprise Systems Architecture/390 Principles of Operation (SA22-7201) 76and the z/Architecture Principles of Operation (SA22-7832). 77</p> 78<p>Each instruction has two major parts, the instruction mnemonic 79and the instruction operands. The instruction format varies. 80</p> 81<table class="menu" border="0" cellspacing="0"> 82<tr><td align="left" valign="top">• <a href="s390-Register.html#s390-Register" accesskey="1">s390 Register</a>:</td><td> </td><td align="left" valign="top">Register Naming 83</td></tr> 84<tr><td align="left" valign="top">• <a href="s390-Mnemonics.html#s390-Mnemonics" accesskey="2">s390 Mnemonics</a>:</td><td> </td><td align="left" valign="top">Instruction Mnemonics 85</td></tr> 86<tr><td align="left" valign="top">• <a href="s390-Operands.html#s390-Operands" accesskey="3">s390 Operands</a>:</td><td> </td><td align="left" valign="top">Instruction Operands 87</td></tr> 88<tr><td align="left" valign="top">• <a href="s390-Formats.html#s390-Formats" accesskey="4">s390 Formats</a>:</td><td> </td><td align="left" valign="top">Instruction Formats 89</td></tr> 90<tr><td align="left" valign="top">• <a href="s390-Aliases.html#s390-Aliases" accesskey="5">s390 Aliases</a>:</td><td> </td><td align="left" valign="top">Instruction Aliases 91</td></tr> 92<tr><td align="left" valign="top">• <a href="s390-Operand-Modifier.html#s390-Operand-Modifier" accesskey="6">s390 Operand Modifier</a>:</td><td> </td><td align="left" valign="top">Instruction Operand Modifier 93</td></tr> 94<tr><td align="left" valign="top">• <a href="s390-Instruction-Marker.html#s390-Instruction-Marker" accesskey="7">s390 Instruction Marker</a>:</td><td> </td><td align="left" valign="top">Instruction Marker 95</td></tr> 96<tr><td align="left" valign="top">• <a href="s390-Literal-Pool-Entries.html#s390-Literal-Pool-Entries" accesskey="8">s390 Literal Pool Entries</a>:</td><td> </td><td align="left" valign="top">Literal Pool Entries 97</td></tr> 98</table> 99 100 101 102 103</body> 104</html> 105