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77 lines
3.6 KiB
HTML
77 lines
3.6 KiB
HTML
15 years ago
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<title>Absolute Literals Directive - Using as</title>
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<meta http-equiv="Content-Type" content="text/html">
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<meta name="description" content="Using as">
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<meta name="generator" content="makeinfo 4.7">
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<link title="Top" rel="start" href="index.html#Top">
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<link rel="up" href="Xtensa-Directives.html#Xtensa-Directives" title="Xtensa Directives">
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<link rel="prev" href="Literal-Prefix-Directive.html#Literal-Prefix-Directive" title="Literal Prefix Directive">
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<link href="http://www.gnu.org/software/texinfo/" rel="generator-home" title="Texinfo Homepage">
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<!--
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This file documents the GNU Assembler "as".
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Copyright (C) 1991, 92, 93, 94, 95, 96, 97, 98, 99, 2000, 2001, 2002,
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2006, 2007 Free Software Foundation, Inc.
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Permission is granted to copy, distribute and/or modify this document
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under the terms of the GNU Free Documentation License, Version 1.1
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or any later version published by the Free Software Foundation;
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with no Invariant Sections, with no Front-Cover Texts, and with no
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Back-Cover Texts. A copy of the license is included in the
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section entitled ``GNU Free Documentation License''.
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man end-->
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<meta http-equiv="Content-Style-Type" content="text/css">
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<style type="text/css"><!--
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pre.display { font-family:inherit }
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pre.format { font-family:inherit }
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pre.smalldisplay { font-family:inherit; font-size:smaller }
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pre.smallformat { font-family:inherit; font-size:smaller }
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pre.smallexample { font-size:smaller }
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pre.smalllisp { font-size:smaller }
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span.sc { font-variant:small-caps }
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span.roman { font-family: serif; font-weight: normal; }
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--></style>
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</head>
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<body>
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<div class="node">
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<p>
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<a name="Absolute-Literals-Directive"></a>Previous: <a rel="previous" accesskey="p" href="Literal-Prefix-Directive.html#Literal-Prefix-Directive">Literal Prefix Directive</a>,
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Up: <a rel="up" accesskey="u" href="Xtensa-Directives.html#Xtensa-Directives">Xtensa Directives</a>
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<hr><br>
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</div>
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<h5 class="subsubsection">9.36.5.7 absolute-literals</h5>
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<p><a name="index-_0040code_007babsolute_002dliterals_007d-directive-1893"></a><a name="index-_0040code_007bno_002dabsolute_002dliterals_007d-directive-1894"></a>
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The <code>absolute-literals</code> and <code>no-absolute-literals</code>
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directives control the absolute vs. PC-relative mode for <code>L32R</code>
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instructions. These are relevant only for Xtensa configurations that
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include the absolute addressing option for <code>L32R</code> instructions.
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<pre class="smallexample"> .begin [no-]absolute-literals
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.end [no-]absolute-literals
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</pre>
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<p>These directives do not change the <code>L32R</code> mode—they only cause
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the assembler to emit the appropriate kind of relocation for <code>L32R</code>
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instructions and to place the literal values in the appropriate section.
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To change the <code>L32R</code> mode, the program must write the
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<code>LITBASE</code> special register. It is the programmer's responsibility
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to keep track of the mode and indicate to the assembler which mode is
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used in each region of code.
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<p>If the Xtensa configuration includes the absolute <code>L32R</code> addressing
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option, the default is to assume absolute <code>L32R</code> addressing unless
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the <span class="samp">--no-absolute-literals</span> command-line option is specified.
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Otherwise, the default is to assume PC-relative <code>L32R</code> addressing.
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The <code>absolute-literals</code> directive can then be used to override
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the default determined by the command-line options.
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</body></html>
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