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 <h2 class="appendix">Appendix I Trace File Format</h2>

 <p><a name="index-trace-file-format-3678"></a>
 The trace file comes in three parts: a header, a textual description
 section, and a trace frame section with binary data.

    <p>The header has the form <code>\x7fTRACE0\n</code>.  The first byte is
 <code>0x7f</code> so as to indicate that the file contains binary data,
 while the <code>0</code> is a version number that may have different values
 in the future.

    <p>The description section consists of multiple lines of <span class="sc">ascii</span> text
 separated by newline characters (<code>0xa</code>).  The lines may include a
 variety of optional descriptive or context-setting information, such
 as tracepoint definitions or register set size.  <span class="sc">gdb</span> will
 ignore any line that it does not recognize.  An empty line marks the end
 of this section.

      <dl>
 <dt><code>R </code><var>size</var><dd>Specifies the size of a register block in bytes.  This is equal to the
 size of a <code>g</code> packet payload in the remote protocol.  <var>size</var>
 is an ascii decimal number.  There should be only one such line in
 a single trace file.

      <br><dt><code>status </code><var>status</var><dd>Trace status.  <var>status</var> has the same format as a <code>qTStatus</code>
 remote packet reply.  There should be only one such line in a single trace
 file.

      <br><dt><code>tp </code><var>payload</var><dd>Tracepoint definition.  The <var>payload</var> has the same format as
 <code>qTfP</code>/<code>qTsP</code> remote packet reply payload.  A single tracepoint
 may take multiple lines of definition, corresponding to the multiple
 reply packets.

      <br><dt><code>tsv </code><var>payload</var><dd>Trace state variable definition.  The <var>payload</var> has the same format as
 <code>qTfV</code>/<code>qTsV</code> remote packet reply payload.  A single variable
 may take multiple lines of definition, corresponding to the multiple
 reply packets.

      <br><dt><code>tdesc </code><var>payload</var><dd>Target description in XML format.  The <var>payload</var> is a single line of
 the XML file.  All such lines should be concatenated together to get
 the original XML file.  This file is in the same format as <code>qXfer</code>
 <code>features</code> payload, and corresponds to the main <code>target.xml</code>
 file.  Includes are not allowed.

    </dl>

    <p>The trace frame section consists of a number of consecutive frames.
 Each frame begins with a two-byte tracepoint number, followed by a
 four-byte size giving the amount of data in the frame.  The data in
 the frame consists of a number of blocks, each introduced by a
 character indicating its type (at least register, memory, and trace
 state variable).  The data in this section is raw binary, not a
 hexadecimal or other encoding; its endianness matches the target's
 endianness.

 <!-- FIXME bi-arch may require endianness/arch info in description section -->
      <dl>
 <dt><code>R </code><var>bytes</var><dd>Register block.  The number and ordering of bytes matches that of a
 <code>g</code> packet in the remote protocol.  Note that these are the
 actual bytes, in target order, not a hexadecimal encoding.

      <br><dt><code>M </code><var>address</var> <var>length</var> <var>bytes</var><code>...</code><dd>Memory block.  This is a contiguous block of memory, at the 8-byte
 address <var>address</var>, with a 2-byte length <var>length</var>, followed by
 <var>length</var> bytes.

      <br><dt><code>V </code><var>number</var> <var>value</var><dd>Trace state variable block.  This records the 8-byte signed value
 <var>value</var> of trace state variable numbered <var>number</var>.

    </dl>

    <p>Future enhancements of the trace file format may include additional types
 of blocks.

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	<h2 class="appendix">Appendix I Trace File Format</h2>

	<p><a name="index-trace-file-format-3678"></a>
	The trace file comes in three parts: a header, a textual description
	section, and a trace frame section with binary data.

	<p>The header has the form <code>\x7fTRACE0\n</code>. The first byte is
	<code>0x7f</code> so as to indicate that the file contains binary data,
	while the <code>0</code> is a version number that may have different values
	in the future.

	<p>The description section consists of multiple lines of <span class="sc">ascii</span> text
	separated by newline characters (<code>0xa</code>). The lines may include a
	variety of optional descriptive or context-setting information, such
	as tracepoint definitions or register set size. <span class="sc">gdb</span> will
	ignore any line that it does not recognize. An empty line marks the end
	of this section.

	<dl>
	<dt><code>R </code><var>size</var><dd>Specifies the size of a register block in bytes. This is equal to the
	size of a <code>g</code> packet payload in the remote protocol. <var>size</var>
	is an ascii decimal number. There should be only one such line in
	a single trace file.

	<br><dt><code>status </code><var>status</var><dd>Trace status. <var>status</var> has the same format as a <code>qTStatus</code>
	remote packet reply. There should be only one such line in a single trace
	file.

	<br><dt><code>tp </code><var>payload</var><dd>Tracepoint definition. The <var>payload</var> has the same format as
	<code>qTfP</code>/<code>qTsP</code> remote packet reply payload. A single tracepoint
	may take multiple lines of definition, corresponding to the multiple
	reply packets.

	<br><dt><code>tsv </code><var>payload</var><dd>Trace state variable definition. The <var>payload</var> has the same format as
	<code>qTfV</code>/<code>qTsV</code> remote packet reply payload. A single variable
	may take multiple lines of definition, corresponding to the multiple
	reply packets.

	<br><dt><code>tdesc </code><var>payload</var><dd>Target description in XML format. The <var>payload</var> is a single line of
	the XML file. All such lines should be concatenated together to get
	the original XML file. This file is in the same format as <code>qXfer</code>
	<code>features</code> payload, and corresponds to the main <code>target.xml</code>
	file. Includes are not allowed.

	</dl>

	<p>The trace frame section consists of a number of consecutive frames.
	Each frame begins with a two-byte tracepoint number, followed by a
	four-byte size giving the amount of data in the frame. The data in
	the frame consists of a number of blocks, each introduced by a
	character indicating its type (at least register, memory, and trace
	state variable). The data in this section is raw binary, not a
	hexadecimal or other encoding; its endianness matches the target's
	endianness.

	<!-- FIXME bi-arch may require endianness/arch info in description section -->
	<dl>
	<dt><code>R </code><var>bytes</var><dd>Register block. The number and ordering of bytes matches that of a
	<code>g</code> packet in the remote protocol. Note that these are the
	actual bytes, in target order, not a hexadecimal encoding.

	<br><dt><code>M </code><var>address</var> <var>length</var> <var>bytes</var><code>...</code><dd>Memory block. This is a contiguous block of memory, at the 8-byte
	address <var>address</var>, with a 2-byte length <var>length</var>, followed by
	<var>length</var> bytes.

	<br><dt><code>V </code><var>number</var> <var>value</var><dd>Trace state variable block. This records the 8-byte signed value
	<var>value</var> of trace state variable numbered <var>number</var>.

	</dl>

	<p>Future enhancements of the trace file format may include additional types
	of blocks.

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