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diff --git a/share/doc/gcc/Cross_002dprofiling.html b/share/doc/gcc/Cross_002dprofiling.html new file mode 100644 index 0000000..05770a8 --- /dev/null +++ b/share/doc/gcc/Cross_002dprofiling.html @@ -0,0 +1,125 @@ +<!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): Cross-profiling</title> + +<meta name="description" content="Using the GNU Compiler Collection (GCC): Cross-profiling"> +<meta name="keywords" content="Using the GNU Compiler Collection (GCC): Cross-profiling"> +<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="Gcov.html#Gcov" rel="up" title="Gcov"> +<link href="Freestanding-Environments.html#Freestanding-Environments" rel="next" title="Freestanding Environments"> +<link href="Gcov-Data-Files.html#Gcov-Data-Files" rel="previous" title="Gcov Data Files"> +<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="Cross_002dprofiling"></a> +<div class="header"> +<p> +Next: <a href="Freestanding-Environments.html#Freestanding-Environments" accesskey="n" rel="next">Freestanding Environments</a>, Previous: <a href="Gcov-Data-Files.html#Gcov-Data-Files" accesskey="p" rel="previous">Gcov Data Files</a>, Up: <a href="Gcov.html#Gcov" accesskey="u" rel="up">Gcov</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="Data-File-Relocation-to-Support-Cross_002dProfiling"></a> +<h3 class="section">10.5 Data File Relocation to Support Cross-Profiling</h3> + +<p>Running the program will cause profile output to be generated. For each +source file compiled with <samp>-fprofile-arcs</samp>, an accompanying <samp>.gcda</samp> +file will be placed in the object file directory. That implicitly requires +running the program on the same system as it was built or having the same +absolute directory structure on the target system. The program will try +to create the needed directory structure, if it is not already present. +</p> +<p>To support cross-profiling, a program compiled with <samp>-fprofile-arcs</samp> +can relocate the data files based on two environment variables: +</p> +<ul> +<li> GCOV_PREFIX contains the prefix to add to the absolute paths +in the object file. Prefix can be absolute, or relative. The +default is no prefix. + +</li><li> GCOV_PREFIX_STRIP indicates the how many initial directory names to strip off +the hardwired absolute paths. Default value is 0. + +<p><em>Note:</em> If GCOV_PREFIX_STRIP is set without GCOV_PREFIX is undefined, + then a relative path is made out of the hardwired absolute paths. +</p></li></ul> + +<p>For example, if the object file <samp>/user/build/foo.o</samp> was built with +<samp>-fprofile-arcs</samp>, the final executable will try to create the data file +<samp>/user/build/foo.gcda</samp> when running on the target system. This will +fail if the corresponding directory does not exist and it is unable to create +it. This can be overcome by, for example, setting the environment as +‘<samp>GCOV_PREFIX=/target/run</samp>’ and ‘<samp>GCOV_PREFIX_STRIP=1</samp>’. Such a +setting will name the data file <samp>/target/run/build/foo.gcda</samp>. +</p> +<p>You must move the data files to the expected directory tree in order to +use them for profile directed optimizations (<samp>-fprofile-use</samp>), or to +use the <code>gcov</code> tool. +</p> +<hr> +<div class="header"> +<p> +Next: <a href="Freestanding-Environments.html#Freestanding-Environments" accesskey="n" rel="next">Freestanding Environments</a>, Previous: <a href="Gcov-Data-Files.html#Gcov-Data-Files" accesskey="p" rel="previous">Gcov Data Files</a>, Up: <a href="Gcov.html#Gcov" accesskey="u" rel="up">Gcov</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> |