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| author | alk3pInjection <webmaster@raspii.tech> | 2024-02-04 16:16:35 +0800 |
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| committer | alk3pInjection <webmaster@raspii.tech> | 2024-02-04 16:16:35 +0800 |
| commit | abdaadbcae30fe0c9a66c7516798279fdfd97750 (patch) | |
| tree | 00a54a6e25601e43876d03c1a4a12a749d4a914c /share/doc/gdb/Optimized-Code.html | |
https://developer.arm.com/downloads/-/arm-gnu-toolchain-downloads
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diff --git a/share/doc/gdb/Optimized-Code.html b/share/doc/gdb/Optimized-Code.html new file mode 100644 index 0000000..140144a --- /dev/null +++ b/share/doc/gdb/Optimized-Code.html @@ -0,0 +1,117 @@ +<!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 "Free Software" and "Free Software Needs +Free Documentation", with the Front-Cover Texts being "A GNU Manual," +and with the Back-Cover Texts as in (a) below. + +(a) The FSF's Back-Cover Text is: "You are free to copy and modify +this GNU Manual. Buying copies from GNU Press supports the FSF in +developing GNU and promoting software freedom." --> +<!-- Created by GNU Texinfo 5.1, http://www.gnu.org/software/texinfo/ --> +<head> +<title>Debugging with GDB: Optimized Code</title> + +<meta name="description" content="Debugging with GDB: Optimized Code"> +<meta name="keywords" content="Debugging with GDB: Optimized Code"> +<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="Concept-Index.html#Concept-Index" rel="index" title="Concept Index"> +<link href="index.html#SEC_Contents" rel="contents" title="Table of Contents"> +<link href="index.html#Top" rel="up" title="Top"> +<link href="Inline-Functions.html#Inline-Functions" rel="next" title="Inline Functions"> +<link href="Value-Sizes.html#Value-Sizes" rel="previous" title="Value Sizes"> +<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="Optimized-Code"></a> +<div class="header"> +<p> +Next: <a href="Macros.html#Macros" accesskey="n" rel="next">Macros</a>, Previous: <a href="Data.html#Data" accesskey="p" rel="previous">Data</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="Concept-Index.html#Concept-Index" title="Index" rel="index">Index</a>]</p> +</div> +<hr> +<a name="Debugging-Optimized-Code"></a> +<h2 class="chapter">11 Debugging Optimized Code</h2> +<a name="index-optimized-code_002c-debugging"></a> +<a name="index-debugging-optimized-code"></a> + +<p>Almost all compilers support optimization. With optimization +disabled, the compiler generates assembly code that corresponds +directly to your source code, in a simplistic way. As the compiler +applies more powerful optimizations, the generated assembly code +diverges from your original source code. With help from debugging +information generated by the compiler, <small>GDB</small> can map from +the running program back to constructs from your original source. +</p> +<p><small>GDB</small> is more accurate with optimization disabled. If you +can recompile without optimization, it is easier to follow the +progress of your program during debugging. But, there are many cases +where you may need to debug an optimized version. +</p> +<p>When you debug a program compiled with ‘<samp>-g -O</samp>’, remember that the +optimizer has rearranged your code; the debugger shows you what is +really there. Do not be too surprised when the execution path does not +exactly match your source file! An extreme example: if you define a +variable, but never use it, <small>GDB</small> never sees that +variable—because the compiler optimizes it out of existence. +</p> +<p>Some things do not work as well with ‘<samp>-g -O</samp>’ as with just +‘<samp>-g</samp>’, particularly on machines with instruction scheduling. If in +doubt, recompile with ‘<samp>-g</samp>’ alone, and if this fixes the problem, +please report it to us as a bug (including a test case!). +See <a href="Variables.html#Variables">Variables</a>, for more information about debugging optimized code. +</p> +<table class="menu" border="0" cellspacing="0"> +<tr><td align="left" valign="top">• <a href="Inline-Functions.html#Inline-Functions" accesskey="1">Inline Functions</a>:</td><td> </td><td align="left" valign="top">How <small>GDB</small> presents inlining +</td></tr> +<tr><td align="left" valign="top">• <a href="Tail-Call-Frames.html#Tail-Call-Frames" accesskey="2">Tail Call Frames</a>:</td><td> </td><td align="left" valign="top"><small>GDB</small> analysis of jumps to functions +</td></tr> +</table> + +<hr> +<div class="header"> +<p> +Next: <a href="Macros.html#Macros" accesskey="n" rel="next">Macros</a>, Previous: <a href="Data.html#Data" accesskey="p" rel="previous">Data</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="Concept-Index.html#Concept-Index" title="Index" rel="index">Index</a>]</p> +</div> + + + +</body> +</html> |