<html lang="en"> <head> <title>Literal Position Directive - Using as</title> <meta http-equiv="Content-Type" content="text/html"> <meta name="description" content="Using as"> <meta name="generator" content="makeinfo 4.7"> <link title="Top" rel="start" href="index.html#Top"> <link rel="up" href="Xtensa-Directives.html#Xtensa-Directives" title="Xtensa Directives"> <link rel="prev" href="Literal-Directive.html#Literal-Directive" title="Literal Directive"> <link rel="next" href="Literal-Prefix-Directive.html#Literal-Prefix-Directive" title="Literal Prefix Directive"> <link href="http://www.gnu.org/software/texinfo/" rel="generator-home" title="Texinfo Homepage"> <!-- This file documents the GNU Assembler "as". Copyright (C) 1991, 92, 93, 94, 95, 96, 97, 98, 99, 2000, 2001, 2002, 2006, 2007 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 1.1 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''. man end--> <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; } --></style> </head> <body> <div class="node"> <p> <a name="Literal-Position-Directive"></a>Next: <a rel="next" accesskey="n" href="Literal-Prefix-Directive.html#Literal-Prefix-Directive">Literal Prefix Directive</a>, Previous: <a rel="previous" accesskey="p" href="Literal-Directive.html#Literal-Directive">Literal Directive</a>, Up: <a rel="up" accesskey="u" href="Xtensa-Directives.html#Xtensa-Directives">Xtensa Directives</a> <hr><br> </div> <h5 class="subsubsection">9.36.5.5 literal_position</h5> <p><a name="index-_0040code_007bliteral_005fposition_007d-directive-1891"></a> When using <span class="samp">--text-section-literals</span> to place literals inline in the section being assembled, the <code>.literal_position</code> directive can be used to mark a potential location for a literal pool. <pre class="smallexample"> .literal_position </pre> <p>The <code>.literal_position</code> directive is ignored when the <span class="samp">--text-section-literals</span> option is not used or when <code>L32R</code> instructions use the absolute addressing mode. <p>The assembler will automatically place text section literal pools before <code>ENTRY</code> instructions, so the <code>.literal_position</code> directive is only needed to specify some other location for a literal pool. You may need to add an explicit jump instruction to skip over an inline literal pool. <p>For example, an interrupt vector does not begin with an <code>ENTRY</code> instruction so the assembler will be unable to automatically find a good place to put a literal pool. Moreover, the code for the interrupt vector must be at a specific starting address, so the literal pool cannot come before the start of the code. The literal pool for the vector must be explicitly positioned in the middle of the vector (before any uses of the literals, due to the negative offsets used by PC-relative <code>L32R</code> instructions). The <code>.literal_position</code> directive can be used to do this. In the following code, the literal for <span class="samp">M</span> will automatically be aligned correctly and is placed after the unconditional jump. <pre class="smallexample"> .global M code_start: j continue .literal_position .align 4 continue: movi a4, M </pre> </body></html>