toolchain/share/doc/gdb/Varying-Target-Capabilities...

80 lines
3.3 KiB
HTML
Raw Permalink Normal View History

2024-01-10 05:24:32 +00:00
<html lang="en">
<head>
<title>Varying Target Capabilities - Debugging with GDB</title>
<meta http-equiv="Content-Type" content="text/html">
<meta name="description" content="Debugging with GDB">
<meta name="generator" content="makeinfo 4.13">
<link title="Top" rel="start" href="index.html#Top">
<link rel="up" href="Agent-Expressions.html#Agent-Expressions" title="Agent Expressions">
<link rel="prev" href="Using-Agent-Expressions.html#Using-Agent-Expressions" title="Using Agent Expressions">
<link rel="next" href="Rationale.html#Rationale" title="Rationale">
<link href="http://www.gnu.org/software/texinfo/" rel="generator-home" title="Texinfo Homepage">
<!--
Copyright (C) 1988-2019 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.''
-->
<meta http-equiv="Content-Style-Type" content="text/css">
<style type="text/css"><!--
pre.display { font-family:inherit }
pre.format { font-family:inherit }
pre.smalldisplay { font-family:inherit; font-size:smaller }
pre.smallformat { font-family:inherit; font-size:smaller }
pre.smallexample { font-size:smaller }
pre.smalllisp { font-size:smaller }
span.sc { font-variant:small-caps }
span.roman { font-family:serif; font-weight:normal; }
span.sansserif { font-family:sans-serif; font-weight:normal; }
--></style>
</head>
<body>
<div class="node">
<a name="Varying-Target-Capabilities"></a>
<p>
Next:&nbsp;<a rel="next" accesskey="n" href="Rationale.html#Rationale">Rationale</a>,
Previous:&nbsp;<a rel="previous" accesskey="p" href="Using-Agent-Expressions.html#Using-Agent-Expressions">Using Agent Expressions</a>,
Up:&nbsp;<a rel="up" accesskey="u" href="Agent-Expressions.html#Agent-Expressions">Agent Expressions</a>
<hr>
</div>
<h3 class="section">F.4 Varying Target Capabilities</h3>
<p>Some targets don't support floating-point, and some would rather not
have to deal with <code>long long</code> operations. Also, different targets
will have different stack sizes, and different bytecode buffer lengths.
<p>Thus, GDB needs a way to ask the target about itself. We haven't worked
out the details yet, but in general, GDB should be able to send the
target a packet asking it to describe itself. The reply should be a
packet whose length is explicit, so we can add new information to the
packet in future revisions of the agent, without confusing old versions
of GDB, and it should contain a version number. It should contain at
least the following information:
<ul>
<li>whether floating point is supported
<li>whether <code>long long</code> is supported
<li>maximum acceptable size of bytecode stack
<li>maximum acceptable length of bytecode expressions
<li>which registers are actually available for collection
<li>whether the target supports disabled tracepoints
</ul>
</body></html>