toolchain/share/doc/as.html/Nops.html

65 lines
2.8 KiB
HTML

<html lang="en">
<head>
<title>Nops - Using as</title>
<meta http-equiv="Content-Type" content="text/html">
<meta name="description" content="Using as">
<meta name="generator" content="makeinfo 4.13">
<link title="Top" rel="start" href="index.html#Top">
<link rel="up" href="Pseudo-Ops.html#Pseudo-Ops" title="Pseudo Ops">
<link rel="prev" href="Nolist.html#Nolist" title="Nolist">
<link rel="next" href="Octa.html#Octa" title="Octa">
<link href="http://www.gnu.org/software/texinfo/" rel="generator-home" title="Texinfo Homepage">
<!--
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''.
-->
<meta http-equiv="Content-Style-Type" content="text/css">
<style type="text/css"><!--
pre.display { font-family:inherit }
pre.format { font-family:inherit }
pre.smalldisplay { font-family:inherit; font-size:smaller }
pre.smallformat { font-family:inherit; font-size:smaller }
pre.smallexample { font-size:smaller }
pre.smalllisp { font-size:smaller }
span.sc { font-variant:small-caps }
span.roman { font-family:serif; font-weight:normal; }
span.sansserif { font-family:sans-serif; font-weight:normal; }
--></style>
</head>
<body>
<div class="node">
<a name="Nops"></a>
<p>
Next:&nbsp;<a rel="next" accesskey="n" href="Octa.html#Octa">Octa</a>,
Previous:&nbsp;<a rel="previous" accesskey="p" href="Nolist.html#Nolist">Nolist</a>,
Up:&nbsp;<a rel="up" accesskey="u" href="Pseudo-Ops.html#Pseudo-Ops">Pseudo Ops</a>
<hr>
</div>
<h3 class="section">7.65 <code>.nops </code><var>size</var><code>[, </code><var>control</var><code>]</code></h3>
<p><a name="index-g_t_0040code_007bnops_007d-directive-421"></a><a name="index-filling-memory-with-no_002dop-instructions-422"></a>This directive emits <var>size</var> bytes filled with no-op instructions.
<var>size</var> is absolute expression, which must be a positve value.
<var>control</var> controls how no-op instructions should be generated. If
the comma and <var>control</var> are omitted, <var>control</var> is assumed to be
zero.
<p>Note: For Intel 80386 and AMD x86-64 targets, <var>control</var> specifies
the size limit of a no-op instruction. The valid values of <var>control</var>
are between 0 and 4 in 16-bit mode, between 0 and 7 when tuning for
older processors in 32-bit mode, between 0 and 11 in 64-bit mode or when
tuning for newer processors in 32-bit mode. When 0 is used, the no-op
instruction size limit is set to the maximum supported size.
</body></html>