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diff --git a/share/doc/gccint/Target-Structure.html b/share/doc/gccint/Target-Structure.html new file mode 100644 index 0000000..e29f12f --- /dev/null +++ b/share/doc/gccint/Target-Structure.html @@ -0,0 +1,145 @@ +<!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: Target Structure</title> + +<meta name="description" content="GNU Compiler Collection (GCC) Internals: Target Structure"> +<meta name="keywords" content="GNU Compiler Collection (GCC) Internals: Target Structure"> +<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="Target-Macros.html#Target-Macros" rel="up" title="Target Macros"> +<link href="Driver.html#Driver" rel="next" title="Driver"> +<link href="Target-Macros.html#Target-Macros" rel="previous" title="Target Macros"> +<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="Target-Structure"></a> +<div class="header"> +<p> +Next: <a href="Driver.html#Driver" accesskey="n" rel="next">Driver</a>, Up: <a href="Target-Macros.html#Target-Macros" accesskey="u" rel="up">Target Macros</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="The-Global-targetm-Variable"></a> +<h3 class="section">18.1 The Global <code>targetm</code> Variable</h3> +<a name="index-target-hooks"></a> +<a name="index-target-functions"></a> + +<dl> +<dt><a name="index-targetm"></a>Variable: <em>struct gcc_target</em> <strong>targetm</strong></dt> +<dd><p>The target <samp>.c</samp> file must define the global <code>targetm</code> variable +which contains pointers to functions and data relating to the target +machine. The variable is declared in <samp>target.h</samp>; +<samp>target-def.h</samp> defines the macro <code>TARGET_INITIALIZER</code> which is +used to initialize the variable, and macros for the default initializers +for elements of the structure. The <samp>.c</samp> file should override those +macros for which the default definition is inappropriate. For example: +</p><div class="smallexample"> +<pre class="smallexample">#include "target.h" +#include "target-def.h" + +/* <span class="roman">Initialize the GCC target structure.</span> */ + +#undef TARGET_COMP_TYPE_ATTRIBUTES +#define TARGET_COMP_TYPE_ATTRIBUTES <var>machine</var>_comp_type_attributes + +struct gcc_target targetm = TARGET_INITIALIZER; +</pre></div> +</dd></dl> + +<p>Where a macro should be defined in the <samp>.c</samp> file in this manner to +form part of the <code>targetm</code> structure, it is documented below as a +“Target Hook” with a prototype. Many macros will change in future +from being defined in the <samp>.h</samp> file to being part of the +<code>targetm</code> structure. +</p> +<p>Similarly, there is a <code>targetcm</code> variable for hooks that are +specific to front ends for C-family languages, documented as “C +Target Hook”. This is declared in <samp>c-family/c-target.h</samp>, the +initializer <code>TARGETCM_INITIALIZER</code> in +<samp>c-family/c-target-def.h</samp>. If targets initialize <code>targetcm</code> +themselves, they should set <code>target_has_targetcm=yes</code> in +<samp>config.gcc</samp>; otherwise a default definition is used. +</p> +<p>Similarly, there is a <code>targetm_common</code> variable for hooks that +are shared between the compiler driver and the compilers proper, +documented as “Common Target Hook”. This is declared in +<samp>common/common-target.h</samp>, the initializer +<code>TARGETM_COMMON_INITIALIZER</code> in +<samp>common/common-target-def.h</samp>. If targets initialize +<code>targetm_common</code> themselves, they should set +<code>target_has_targetm_common=yes</code> in <samp>config.gcc</samp>; otherwise a +default definition is used. +</p> +<p>Similarly, there is a <code>targetdm</code> variable for hooks that are +specific to the D language front end, documented as “D Target Hook”. +This is declared in <samp>d/d-target.h</samp>, the initializer +<code>TARGETDM_INITIALIZER</code> in <samp>d/d-target-def.h</samp>. If targets +initialize <code>targetdm</code> themselves, they should set +<code>target_has_targetdm=yes</code> in <samp>config.gcc</samp>; otherwise a default +definition is used. +</p> +<hr> +<div class="header"> +<p> +Next: <a href="Driver.html#Driver" accesskey="n" rel="next">Driver</a>, Up: <a href="Target-Macros.html#Target-Macros" accesskey="u" rel="up">Target Macros</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> |