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diff --git a/share/doc/gccint/GENERIC.html b/share/doc/gccint/GENERIC.html new file mode 100644 index 0000000..bf2f5c5 --- /dev/null +++ b/share/doc/gccint/GENERIC.html @@ -0,0 +1,136 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> +<html> +<!-- Copyright (C) 1988-2023 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 1.3 or +any later version published by the Free Software Foundation; with the +Invariant Sections being "Funding Free Software", the Front-Cover +Texts being (a) (see below), and with the Back-Cover Texts being (b) +(see below). A copy of the license is included in the section entitled +"GNU Free Documentation License". + +(a) The FSF's Front-Cover Text is: + +A GNU Manual + +(b) The FSF's Back-Cover Text is: + +You have freedom to copy and modify this GNU Manual, like GNU + software. Copies published by the Free Software Foundation raise + funds for GNU development. --> +<!-- Created by GNU Texinfo 5.1, http://www.gnu.org/software/texinfo/ --> +<head> +<title>GNU Compiler Collection (GCC) Internals: GENERIC</title> + +<meta name="description" content="GNU Compiler Collection (GCC) Internals: GENERIC"> +<meta name="keywords" content="GNU Compiler Collection (GCC) Internals: GENERIC"> +<meta name="resource-type" content="document"> +<meta name="distribution" content="global"> +<meta name="Generator" content="makeinfo"> +<meta http-equiv="Content-Type" content="text/html; charset=utf-8"> +<link href="index.html#Top" rel="start" title="Top"> +<link href="Option-Index.html#Option-Index" rel="index" title="Option Index"> +<link href="index.html#SEC_Contents" rel="contents" title="Table of Contents"> +<link href="index.html#Top" rel="up" title="Top"> +<link href="Deficiencies.html#Deficiencies" rel="next" title="Deficiencies"> +<link href="Guidelines-for-using-poly_005fint.html#Guidelines-for-using-poly_005fint" rel="previous" title="Guidelines for using poly_int"> +<style type="text/css"> +<!-- +a.summary-letter {text-decoration: none} +blockquote.smallquotation {font-size: smaller} +div.display {margin-left: 3.2em} +div.example {margin-left: 3.2em} +div.indentedblock {margin-left: 3.2em} +div.lisp {margin-left: 3.2em} +div.smalldisplay {margin-left: 3.2em} +div.smallexample {margin-left: 3.2em} +div.smallindentedblock {margin-left: 3.2em; font-size: smaller} +div.smalllisp {margin-left: 3.2em} +kbd {font-style:oblique} +pre.display {font-family: inherit} +pre.format {font-family: inherit} +pre.menu-comment {font-family: serif} +pre.menu-preformatted {font-family: serif} +pre.smalldisplay {font-family: inherit; font-size: smaller} +pre.smallexample {font-size: smaller} +pre.smallformat {font-family: inherit; font-size: smaller} +pre.smalllisp {font-size: smaller} +span.nocodebreak {white-space:nowrap} +span.nolinebreak {white-space:nowrap} +span.roman {font-family:serif; font-weight:normal} +span.sansserif {font-family:sans-serif; font-weight:normal} +ul.no-bullet {list-style: none} +--> +</style> + + +</head> + +<body lang="en" bgcolor="#FFFFFF" text="#000000" link="#0000FF" vlink="#800080" alink="#FF0000"> +<a name="GENERIC"></a> +<div class="header"> +<p> +Next: <a href="GIMPLE.html#GIMPLE" accesskey="n" rel="next">GIMPLE</a>, Previous: <a href="poly_005fint.html#poly_005fint" accesskey="p" rel="previous">poly_int</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> +</div> +<hr> +<a name="GENERIC-1"></a> +<h2 class="chapter">11 GENERIC</h2> +<a name="index-GENERIC-1"></a> + +<p>The purpose of GENERIC is simply to provide a +language-independent way of representing an entire function in +trees. To this end, it was necessary to add a few new tree codes +to the back end, but almost everything was already there. If you +can express it with the codes in <code>gcc/tree.def</code>, it’s +GENERIC. +</p> +<p>Early on, there was a great deal of debate about how to think +about statements in a tree IL. In GENERIC, a statement is +defined as any expression whose value, if any, is ignored. A +statement will always have <code>TREE_SIDE_EFFECTS</code> set (or it +will be discarded), but a non-statement expression may also have +side effects. A <code>CALL_EXPR</code>, for instance. +</p> +<p>It would be possible for some local optimizations to work on the +GENERIC form of a function; indeed, the adapted tree inliner +works fine on GENERIC, but the current compiler performs inlining +after lowering to GIMPLE (a restricted form described in the next +section). Indeed, currently the frontends perform this lowering +before handing off to <code>tree_rest_of_compilation</code>, but this +seems inelegant. +</p> +<table class="menu" border="0" cellspacing="0"> +<tr><td align="left" valign="top">• <a href="Deficiencies.html#Deficiencies" accesskey="1">Deficiencies</a>:</td><td> </td><td align="left" valign="top">Topics not yet covered in this document. +</td></tr> +<tr><td align="left" valign="top">• <a href="Tree-overview.html#Tree-overview" accesskey="2">Tree overview</a>:</td><td> </td><td align="left" valign="top">All about <code>tree</code>s. +</td></tr> +<tr><td align="left" valign="top">• <a href="Types.html#Types" accesskey="3">Types</a>:</td><td> </td><td align="left" valign="top">Fundamental and aggregate types. +</td></tr> +<tr><td align="left" valign="top">• <a href="Declarations.html#Declarations" accesskey="4">Declarations</a>:</td><td> </td><td align="left" valign="top">Type declarations and variables. +</td></tr> +<tr><td align="left" valign="top">• <a href="Attributes.html#Attributes" accesskey="5">Attributes</a>:</td><td> </td><td align="left" valign="top">Declaration and type attributes. +</td></tr> +<tr><td align="left" valign="top">• <a href="Expression-trees.html#Expression-trees" accesskey="6">Expressions</a>:</td><td> </td><td align="left" valign="top">Operating on data. +</td></tr> +<tr><td align="left" valign="top">• <a href="Statements.html#Statements" accesskey="7">Statements</a>:</td><td> </td><td align="left" valign="top">Control flow and related trees. +</td></tr> +<tr><td align="left" valign="top">• <a href="Functions.html#Functions" accesskey="8">Functions</a>:</td><td> </td><td align="left" valign="top">Function bodies, linkage, and other aspects. +</td></tr> +<tr><td align="left" valign="top">• <a href="Language_002ddependent-trees.html#Language_002ddependent-trees" accesskey="9">Language-dependent trees</a>:</td><td> </td><td align="left" valign="top">Topics and trees specific to language front ends. +</td></tr> +<tr><td align="left" valign="top">• <a href="C-and-C_002b_002b-Trees.html#C-and-C_002b_002b-Trees">C and C++ Trees</a>:</td><td> </td><td align="left" valign="top">Trees specific to C and C++. +</td></tr> +</table> + + +<hr> +<div class="header"> +<p> +Next: <a href="GIMPLE.html#GIMPLE" accesskey="n" rel="next">GIMPLE</a>, Previous: <a href="poly_005fint.html#poly_005fint" accesskey="p" rel="previous">poly_int</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> +</div> + + + +</body> +</html> |