113 lines
5.0 KiB
HTML
113 lines
5.0 KiB
HTML
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<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
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<html>
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<!-- Copyright (C) 1988-2016 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 1.3 or
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any later version published by the Free Software Foundation; with the
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Invariant Sections being "Funding Free Software", the Front-Cover
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(see below). A copy of the license is included in the section entitled
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"GNU Free Documentation License".
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(a) The FSF's Front-Cover Text is:
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A GNU Manual
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<!-- Created by GNU Texinfo 5.2, http://www.gnu.org/software/texinfo/ -->
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<head>
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<title>Using the GNU Compiler Collection (GCC): H8/300 Variable Attributes</title>
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<meta name="description" content="Using the GNU Compiler Collection (GCC): H8/300 Variable Attributes">
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<meta name="keywords" content="Using the GNU Compiler Collection (GCC): H8/300 Variable Attributes">
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<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
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<link href="index.html#Top" rel="start" title="Top">
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<link href="Option-Index.html#Option-Index" rel="index" title="Option Index">
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<link href="index.html#SEC_Contents" rel="contents" title="Table of Contents">
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<link href="Variable-Attributes.html#Variable-Attributes" rel="up" title="Variable Attributes">
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<link href="IA_002d64-Variable-Attributes.html#IA_002d64-Variable-Attributes" rel="next" title="IA-64 Variable Attributes">
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<link href="Blackfin-Variable-Attributes.html#Blackfin-Variable-Attributes" rel="prev" title="Blackfin Variable Attributes">
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</style>
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</head>
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<body lang="en" bgcolor="#FFFFFF" text="#000000" link="#0000FF" vlink="#800080" alink="#FF0000">
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<a name="H8_002f300-Variable-Attributes"></a>
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<div class="header">
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<p>
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Next: <a href="IA_002d64-Variable-Attributes.html#IA_002d64-Variable-Attributes" accesskey="n" rel="next">IA-64 Variable Attributes</a>, Previous: <a href="Blackfin-Variable-Attributes.html#Blackfin-Variable-Attributes" accesskey="p" rel="prev">Blackfin Variable Attributes</a>, Up: <a href="Variable-Attributes.html#Variable-Attributes" accesskey="u" rel="up">Variable Attributes</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Option-Index.html#Option-Index" title="Index" rel="index">Index</a>]</p>
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</div>
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<hr>
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<a name="H8_002f300-Variable-Attributes-1"></a>
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<h4 class="subsection">6.32.4 H8/300 Variable Attributes</h4>
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<p>These variable attributes are available for H8/300 targets:
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</p>
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<dl compact="compact">
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<dt><code>eightbit_data</code></dt>
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<dd><a name="index-eightbit_005fdata-variable-attribute_002c-H8_002f300"></a>
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<a name="index-eight_002dbit-data-on-the-H8_002f300_002c-H8_002f300H_002c-and-H8S"></a>
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<p>Use this attribute on the H8/300, H8/300H, and H8S to indicate that the specified
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variable should be placed into the eight-bit data section.
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The compiler generates more efficient code for certain operations
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on data in the eight-bit data area. Note the eight-bit data area is limited to
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256 bytes of data.
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</p>
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<p>You must use GAS and GLD from GNU binutils version 2.7 or later for
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this attribute to work correctly.
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</p>
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</dd>
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<dt><code>tiny_data</code></dt>
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<dd><a name="index-tiny_005fdata-variable-attribute_002c-H8_002f300"></a>
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<a name="index-tiny-data-section-on-the-H8_002f300H-and-H8S"></a>
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<p>Use this attribute on the H8/300H and H8S to indicate that the specified
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variable should be placed into the tiny data section.
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The compiler generates more efficient code for loads and stores
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on data in the tiny data section. Note the tiny data area is limited to
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slightly under 32KB of data.
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</p>
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</dd>
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</dl>
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</body>
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</html>
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