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diff --git a/share/doc/gccint/Tree-SSA.html b/share/doc/gccint/Tree-SSA.html new file mode 100644 index 0000000..6093854 --- /dev/null +++ b/share/doc/gccint/Tree-SSA.html @@ -0,0 +1,128 @@ +<!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: Tree SSA</title> + +<meta name="description" content="GNU Compiler Collection (GCC) Internals: Tree SSA"> +<meta name="keywords" content="GNU Compiler Collection (GCC) Internals: Tree SSA"> +<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="Annotations.html#Annotations" rel="next" title="Annotations"> +<link href="Statement-and-operand-traversals.html#Statement-and-operand-traversals" rel="previous" title="Statement and operand traversals"> +<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="Tree-SSA"></a> +<div class="header"> +<p> +Next: <a href="RTL.html#RTL" accesskey="n" rel="next">RTL</a>, Previous: <a href="GIMPLE.html#GIMPLE" accesskey="p" rel="previous">GIMPLE</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="Analysis-and-Optimization-of-GIMPLE-tuples"></a> +<h2 class="chapter">13 Analysis and Optimization of GIMPLE tuples</h2> +<a name="index-Tree-SSA"></a> +<a name="index-Optimization-infrastructure-for-GIMPLE"></a> + +<p>GCC uses three main intermediate languages to represent the program +during compilation: GENERIC, GIMPLE and RTL. GENERIC is a +language-independent representation generated by each front end. It +is used to serve as an interface between the parser and optimizer. +GENERIC is a common representation that is able to represent programs +written in all the languages supported by GCC. +</p> +<p>GIMPLE and RTL are used to optimize the program. GIMPLE is used for +target and language independent optimizations (e.g., inlining, +constant propagation, tail call elimination, redundancy elimination, +etc). Much like GENERIC, GIMPLE is a language independent, tree based +representation. However, it differs from GENERIC in that the GIMPLE +grammar is more restrictive: expressions contain no more than 3 +operands (except function calls), it has no control flow structures +and expressions with side effects are only allowed on the right hand +side of assignments. See the chapter describing GENERIC and GIMPLE +for more details. +</p> +<p>This chapter describes the data structures and functions used in the +GIMPLE optimizers (also known as “tree optimizers” or “middle +end”). In particular, it focuses on all the macros, data structures, +functions and programming constructs needed to implement optimization +passes for GIMPLE. +</p> +<table class="menu" border="0" cellspacing="0"> +<tr><td align="left" valign="top">• <a href="Annotations.html#Annotations" accesskey="1">Annotations</a>:</td><td> </td><td align="left" valign="top">Attributes for variables. +</td></tr> +<tr><td align="left" valign="top">• <a href="SSA-Operands.html#SSA-Operands" accesskey="2">SSA Operands</a>:</td><td> </td><td align="left" valign="top">SSA names referenced by GIMPLE statements. +</td></tr> +<tr><td align="left" valign="top">• <a href="SSA.html#SSA" accesskey="3">SSA</a>:</td><td> </td><td align="left" valign="top">Static Single Assignment representation. +</td></tr> +<tr><td align="left" valign="top">• <a href="Alias-analysis.html#Alias-analysis" accesskey="4">Alias analysis</a>:</td><td> </td><td align="left" valign="top">Representing aliased loads and stores. +</td></tr> +<tr><td align="left" valign="top">• <a href="Memory-model.html#Memory-model" accesskey="5">Memory model</a>:</td><td> </td><td align="left" valign="top">Memory model used by the middle-end. +</td></tr> +</table> + +<hr> +<div class="header"> +<p> +Next: <a href="RTL.html#RTL" accesskey="n" rel="next">RTL</a>, Previous: <a href="GIMPLE.html#GIMPLE" accesskey="p" rel="previous">GIMPLE</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> |