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114 lines
4.8 KiB
HTML
114 lines
4.8 KiB
HTML
4 years ago
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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) 1988-2018 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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Texts being (a) (see below), and with the Back-Cover Texts being (b)
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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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(b) The FSF's Back-Cover Text is:
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You have freedom to copy and modify this GNU Manual, like GNU
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software. Copies published by the Free Software Foundation raise
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funds for GNU development. -->
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<!-- Created by GNU Texinfo 6.4, http://www.gnu.org/software/texinfo/ -->
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<head>
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<title>Languages (GNU Compiler Collection (GCC) Internals)</title>
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<meta name="description" content="Languages (GNU Compiler Collection (GCC) Internals)">
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<meta name="keywords" content="Languages (GNU Compiler Collection (GCC) Internals)">
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<meta name="resource-type" content="document">
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<meta name="distribution" content="global">
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<meta name="Generator" content="makeinfo">
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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="index.html#Top" rel="up" title="Top">
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<link href="Source-Tree.html#Source-Tree" rel="next" title="Source Tree">
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<link href="Miscellaneous-routines.html#Miscellaneous-routines" rel="prev" title="Miscellaneous routines">
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<style type="text/css">
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ul.no-bullet {list-style: none}
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-->
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</style>
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</head>
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<body lang="en">
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<a name="Languages"></a>
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<div class="header">
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<p>
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Next: <a href="Source-Tree.html#Source-Tree" accesskey="n" rel="next">Source Tree</a>, Previous: <a href="Libgcc.html#Libgcc" accesskey="p" rel="prev">Libgcc</a>, Up: <a href="index.html#Top" accesskey="u" rel="up">Top</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="Language-Front-Ends-in-GCC"></a>
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<h2 class="chapter">5 Language Front Ends in GCC</h2>
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<p>The interface to front ends for languages in GCC, and in particular
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the <code>tree</code> structure (see <a href="GENERIC.html#GENERIC">GENERIC</a>), was initially designed for
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C, and many aspects of it are still somewhat biased towards C and
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C-like languages. It is, however, reasonably well suited to other
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procedural languages, and front ends for many such languages have been
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written for GCC.
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</p>
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<p>Writing a compiler as a front end for GCC, rather than compiling
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directly to assembler or generating C code which is then compiled by
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GCC, has several advantages:
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</p>
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<ul>
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<li> GCC front ends benefit from the support for many different
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target machines already present in GCC.
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</li><li> GCC front ends benefit from all the optimizations in GCC. Some
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of these, such as alias analysis, may work better when GCC is
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compiling directly from source code then when it is compiling from
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generated C code.
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</li><li> Better debugging information is generated when compiling
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directly from source code than when going via intermediate generated C
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code.
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</li></ul>
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<p>Because of the advantages of writing a compiler as a GCC front end,
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GCC front ends have also been created for languages very different
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from those for which GCC was designed, such as the declarative
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logic/functional language Mercury. For these reasons, it may also be
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useful to implement compilers created for specialized purposes (for
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example, as part of a research project) as GCC front ends.
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</p>
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</body>
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</html>
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