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91 lines
3.8 KiB
HTML
91 lines
3.8 KiB
HTML
4 years ago
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<html lang="en">
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<head>
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<title>Languages - GNU Compiler Collection (GCC) Internals</title>
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<meta http-equiv="Content-Type" content="text/html">
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<meta name="description" content="GNU Compiler Collection (GCC) Internals">
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<meta name="generator" content="makeinfo 4.13">
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<link title="Top" rel="start" href="index.html#Top">
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<link rel="prev" href="Libgcc.html#Libgcc" title="Libgcc">
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<link rel="next" href="Source-Tree.html#Source-Tree" title="Source Tree">
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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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Copyright (C) 1988-2015 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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--></style>
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</head>
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<body>
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<div class="node">
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<a name="Languages"></a>
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<p>
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Next: <a rel="next" accesskey="n" href="Source-Tree.html#Source-Tree">Source Tree</a>,
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Previous: <a rel="previous" accesskey="p" href="Libgcc.html#Libgcc">Libgcc</a>,
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Up: <a rel="up" accesskey="u" href="index.html#Top">Top</a>
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<hr>
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</div>
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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>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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<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>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>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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</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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<!-- Copyright (C) 2002-2015 Free Software Foundation, Inc. -->
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<!-- This is part of the GCC manual. -->
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<!-- For copying conditions, see the file gcc.texi. -->
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</body></html>
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