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diff --git a/share/doc/gcc/Asm-Labels.html b/share/doc/gcc/Asm-Labels.html new file mode 100644 index 0000000..9b0a6d3 --- /dev/null +++ b/share/doc/gcc/Asm-Labels.html @@ -0,0 +1,139 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> +<html> +<!-- This file documents the use of the GNU compilers. + +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>Using the GNU Compiler Collection (GCC): Asm Labels</title> + +<meta name="description" content="Using the GNU Compiler Collection (GCC): Asm Labels"> +<meta name="keywords" content="Using the GNU Compiler Collection (GCC): Asm Labels"> +<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="Indices.html#Indices" rel="index" title="Indices"> +<link href="index.html#SEC_Contents" rel="contents" title="Table of Contents"> +<link href="Using-Assembly-Language-with-C.html#Using-Assembly-Language-with-C" rel="up" title="Using Assembly Language with C"> +<link href="Explicit-Register-Variables.html#Explicit-Register-Variables" rel="next" title="Explicit Register Variables"> +<link href="Machine-Constraints.html#Machine-Constraints" rel="previous" title="Machine Constraints"> +<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_US" bgcolor="#FFFFFF" text="#000000" link="#0000FF" vlink="#800080" alink="#FF0000"> +<a name="Asm-Labels"></a> +<div class="header"> +<p> +Next: <a href="Explicit-Register-Variables.html#Explicit-Register-Variables" accesskey="n" rel="next">Explicit Register Variables</a>, Previous: <a href="Constraints.html#Constraints" accesskey="p" rel="previous">Constraints</a>, Up: <a href="Using-Assembly-Language-with-C.html#Using-Assembly-Language-with-C" accesskey="u" rel="up">Using Assembly Language with C</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Indices.html#Indices" title="Index" rel="index">Index</a>]</p> +</div> +<hr> +<a name="Controlling-Names-Used-in-Assembler-Code"></a> +<h4 class="subsection">6.47.4 Controlling Names Used in Assembler Code</h4> +<a name="index-assembler-names-for-identifiers"></a> +<a name="index-names-used-in-assembler-code"></a> +<a name="index-identifiers_002c-names-in-assembler-code"></a> + +<p>You can specify the name to be used in the assembler code for a C +function or variable by writing the <code>asm</code> (or <code>__asm__</code>) +keyword after the declarator. +It is up to you to make sure that the assembler names you choose do not +conflict with any other assembler symbols, or reference registers. +</p> +<a name="Assembler-names-for-data"></a> +<h4 class="subsubheading">Assembler names for data</h4> + +<p>This sample shows how to specify the assembler name for data: +</p> +<div class="smallexample"> +<pre class="smallexample">int foo asm ("myfoo") = 2; +</pre></div> + +<p>This specifies that the name to be used for the variable <code>foo</code> in +the assembler code should be ‘<samp>myfoo</samp>’ rather than the usual +‘<samp>_foo</samp>’. +</p> +<p>On systems where an underscore is normally prepended to the name of a C +variable, this feature allows you to define names for the +linker that do not start with an underscore. +</p> +<p>GCC does not support using this feature with a non-static local variable +since such variables do not have assembler names. If you are +trying to put the variable in a particular register, see +<a href="Explicit-Register-Variables.html#Explicit-Register-Variables">Explicit Register Variables</a>. +</p> +<a name="Assembler-names-for-functions"></a> +<h4 class="subsubheading">Assembler names for functions</h4> + +<p>To specify the assembler name for functions, write a declaration for the +function before its definition and put <code>asm</code> there, like this: +</p> +<div class="smallexample"> +<pre class="smallexample">int func (int x, int y) asm ("MYFUNC"); + +int func (int x, int y) +{ + /* <span class="roman">…</span> */ +</pre></div> + +<p>This specifies that the name to be used for the function <code>func</code> in +the assembler code should be <code>MYFUNC</code>. +</p> +<hr> +<div class="header"> +<p> +Next: <a href="Explicit-Register-Variables.html#Explicit-Register-Variables" accesskey="n" rel="next">Explicit Register Variables</a>, Previous: <a href="Constraints.html#Constraints" accesskey="p" rel="previous">Constraints</a>, Up: <a href="Using-Assembly-Language-with-C.html#Using-Assembly-Language-with-C" accesskey="u" rel="up">Using Assembly Language with C</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Indices.html#Indices" title="Index" rel="index">Index</a>]</p> +</div> + + + +</body> +</html> |