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diff --git a/share/doc/gdb/PowerPC-Embedded.html b/share/doc/gdb/PowerPC-Embedded.html new file mode 100644 index 0000000..86150f9 --- /dev/null +++ b/share/doc/gdb/PowerPC-Embedded.html @@ -0,0 +1,166 @@ +<!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: PowerPC Embedded</title> + +<meta name="description" content="Debugging with GDB: PowerPC Embedded"> +<meta name="keywords" content="Debugging with GDB: PowerPC Embedded"> +<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="Embedded-Processors.html#Embedded-Processors" rel="up" title="Embedded Processors"> +<link href="AVR.html#AVR" rel="next" title="AVR"> +<link href="OpenRISC-1000.html#OpenRISC-1000" rel="previous" title="OpenRISC 1000"> +<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="PowerPC-Embedded"></a> +<div class="header"> +<p> +Next: <a href="AVR.html#AVR" accesskey="n" rel="next">AVR</a>, Previous: <a href="OpenRISC-1000.html#OpenRISC-1000" accesskey="p" rel="previous">OpenRISC 1000</a>, Up: <a href="Embedded-Processors.html#Embedded-Processors" accesskey="u" rel="up">Embedded Processors</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="PowerPC-Embedded-1"></a> +<h4 class="subsection">21.3.8 PowerPC Embedded</h4> + +<a name="index-DVC-register"></a> +<p><small>GDB</small> supports using the DVC (Data Value Compare) register to +implement in hardware simple hardware watchpoint conditions of the form: +</p> +<div class="smallexample"> +<pre class="smallexample">(gdb) watch <var>address|variable</var> \ + if <var>address|variable</var> == <var>constant expression</var> +</pre></div> + +<p>The DVC register will be automatically used when <small>GDB</small> detects +such pattern in a condition expression, and the created watchpoint uses one +debug register (either the <code>exact-watchpoints</code> option is on and the +variable is scalar, or the variable has a length of one byte). This feature +is available in native <small>GDB</small> running on a Linux kernel version 2.6.34 +or newer. +</p> +<p>When running on PowerPC embedded processors, <small>GDB</small> automatically uses +ranged hardware watchpoints, unless the <code>exact-watchpoints</code> option is on, +in which case watchpoints using only one debug register are created when +watching variables of scalar types. +</p> +<p>You can create an artificial array to watch an arbitrary memory +region using one of the following commands (see <a href="Expressions.html#Expressions">Expressions</a>): +</p> +<div class="smallexample"> +<pre class="smallexample">(gdb) watch *((char *) <var>address</var>)@<var>length</var> +(gdb) watch {char[<var>length</var>]} <var>address</var> +</pre></div> + +<p>PowerPC embedded processors support masked watchpoints. See the discussion +about the <code>mask</code> argument in <a href="Set-Watchpoints.html#Set-Watchpoints">Set Watchpoints</a>. +</p> +<a name="index-ranged-breakpoint"></a> +<p>PowerPC embedded processors support hardware accelerated +<em>ranged breakpoints</em>. A ranged breakpoint stops execution of +the inferior whenever it executes an instruction at any address within +the range it was set at. To set a ranged breakpoint in <small>GDB</small>, +use the <code>break-range</code> command. +</p> +<p><small>GDB</small> provides the following PowerPC-specific commands: +</p> +<dl compact="compact"> +<dd><a name="index-break_002drange"></a> +</dd> +<dt><code>break-range <var>start-locspec</var>, <var>end-locspec</var></code></dt> +<dd><p>Set a breakpoint for an address range given by <var>start-locspec</var> and +<var>end-locspec</var>, which are location specs. See <a href="Location-Specifications.html#Location-Specifications">Location Specifications</a>, for a list of all the possible forms of location +specs. <small>GDB</small> resolves both <var>start-locspec</var> and +<var>end-locspec</var>, and uses the addresses of the resolved code +locations as start and end addresses of the range to break at. The +breakpoint will stop execution of the inferior whenever it executes an +instruction at any address between the start and end addresses, +inclusive. If either <var>start-locspec</var> or <var>end-locspec</var> resolve +to multiple code locations in the program, then the command aborts +with an error without creating a breakpoint. +</p> +<a name="index-set-powerpc"></a> +</dd> +<dt><code>set powerpc soft-float</code></dt> +<dt><code>show powerpc soft-float</code></dt> +<dd><p>Force <small>GDB</small> to use (or not use) a software floating point calling +convention. By default, <small>GDB</small> selects the calling convention based +on the selected architecture and the provided executable file. +</p> +</dd> +<dt><code>set powerpc vector-abi</code></dt> +<dt><code>show powerpc vector-abi</code></dt> +<dd><p>Force <small>GDB</small> to use the specified calling convention for vector +arguments and return values. The valid options are ‘<samp>auto</samp>’; +‘<samp>generic</samp>’, to avoid vector registers even if they are present; +‘<samp>altivec</samp>’, to use AltiVec registers; and ‘<samp>spe</samp>’ to use SPE +registers. By default, <small>GDB</small> selects the calling convention +based on the selected architecture and the provided executable file. +</p> +</dd> +<dt><code>set powerpc exact-watchpoints</code></dt> +<dt><code>show powerpc exact-watchpoints</code></dt> +<dd><p>Allow <small>GDB</small> to use only one debug register when watching a variable +of scalar type, thus assuming that the variable is accessed through the +address of its first byte. +</p> +</dd> +</dl> + +<hr> +<div class="header"> +<p> +Next: <a href="AVR.html#AVR" accesskey="n" rel="next">AVR</a>, Previous: <a href="OpenRISC-1000.html#OpenRISC-1000" accesskey="p" rel="previous">OpenRISC 1000</a>, Up: <a href="Embedded-Processors.html#Embedded-Processors" accesskey="u" rel="up">Embedded Processors</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> |