[v11,10/10] btrace: Extend ptwrite event decoding.

Message ID 20240725090937.3997414-11-felix.willgerodt@intel.com
State New
Headers
Series Extensions for PTWRITE |

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Commit Message

Willgerodt, Felix July 25, 2024, 9:09 a.m. UTC
  Call the ptwrite filter function whenever a ptwrite event is decoded.
The returned string is written to the aux_data string table and a
corresponding auxiliary instruction is appended to the function segment.

Reviewed-By: Eli Zaretskii <eliz@gnu.org>
Approved-By: Markus Metzger <markus.t.metzger@intel.com>
---
 gdb/NEWS                                  |   7 +
 gdb/btrace.c                              |  45 ++
 gdb/config.in                             |   3 +
 gdb/configure                             |  11 +
 gdb/doc/python.texi                       | 149 ++++++
 gdb/testsuite/gdb.btrace/i386-ptwrite.S   | 550 ++++++++++++++++++++++
 gdb/testsuite/gdb.btrace/ptwrite.c        |  39 ++
 gdb/testsuite/gdb.btrace/ptwrite.exp      | 202 ++++++++
 gdb/testsuite/gdb.btrace/x86_64-ptwrite.S | 544 +++++++++++++++++++++
 gdb/testsuite/lib/gdb.exp                 |  72 +++
 gdbsupport/common.m4                      |   2 +
 gdbsupport/config.in                      |   3 +
 gdbsupport/configure                      |  11 +
 13 files changed, 1638 insertions(+)
 create mode 100644 gdb/testsuite/gdb.btrace/i386-ptwrite.S
 create mode 100644 gdb/testsuite/gdb.btrace/ptwrite.c
 create mode 100644 gdb/testsuite/gdb.btrace/ptwrite.exp
 create mode 100644 gdb/testsuite/gdb.btrace/x86_64-ptwrite.S
  

Comments

Eli Zaretskii July 25, 2024, 11:13 a.m. UTC | #1
> From: Felix Willgerodt <felix.willgerodt@intel.com>
> Date: Thu, 25 Jul 2024 11:09:37 +0200
> 
> Call the ptwrite filter function whenever a ptwrite event is decoded.
> The returned string is written to the aux_data string table and a
> corresponding auxiliary instruction is appended to the function segment.
> 
> Reviewed-By: Eli Zaretskii <eliz@gnu.org>
> Approved-By: Markus Metzger <markus.t.metzger@intel.com>
> ---
>  gdb/NEWS                                  |   7 +
>  gdb/btrace.c                              |  45 ++
>  gdb/config.in                             |   3 +
>  gdb/configure                             |  11 +
>  gdb/doc/python.texi                       | 149 ++++++
>  gdb/testsuite/gdb.btrace/i386-ptwrite.S   | 550 ++++++++++++++++++++++
>  gdb/testsuite/gdb.btrace/ptwrite.c        |  39 ++
>  gdb/testsuite/gdb.btrace/ptwrite.exp      | 202 ++++++++
>  gdb/testsuite/gdb.btrace/x86_64-ptwrite.S | 544 +++++++++++++++++++++
>  gdb/testsuite/lib/gdb.exp                 |  72 +++
>  gdbsupport/common.m4                      |   2 +
>  gdbsupport/config.in                      |   3 +
>  gdbsupport/configure                      |  11 +
>  13 files changed, 1638 insertions(+)
>  create mode 100644 gdb/testsuite/gdb.btrace/i386-ptwrite.S
>  create mode 100644 gdb/testsuite/gdb.btrace/ptwrite.c
>  create mode 100644 gdb/testsuite/gdb.btrace/ptwrite.exp
>  create mode 100644 gdb/testsuite/gdb.btrace/x86_64-ptwrite.S

Thanks.

> +* GDB now supports printing of ptwrite payloads from the Intel Processor
> +  Trace during 'record instruction-history', 'record function-call-history'
> +  and all stepping commands.

The last sentence above reads as an incomplete sentence.

> +If an inferior uses the instruction, @value{GDBN} by default inserts the
> +raw payload value as auxiliary information into the execution history.
> +Auxiliary information is by default printed during
> +@code{record instruction-history}, @code{record function-call-history},
> +and all stepping commands, and is accessible in Python as a
> +@code{RecordAuxiliary} object.

What is the RecordAuxiliary object?  Is it described in the manual?
And I think this could benefit from a cross-reference to where "record
instruction-history" and "record function-call-history" are described.

Reviewed-By: Eli Zaretskii <eliz@gnu.org>
  
Willgerodt, Felix July 25, 2024, 12:15 p.m. UTC | #2
> -----Original Message-----
> From: Eli Zaretskii <eliz@gnu.org>
> Sent: Donnerstag, 25. Juli 2024 13:14
> To: Willgerodt, Felix <felix.willgerodt@intel.com>
> Cc: gdb-patches@sourceware.org; Metzger, Markus T
> <markus.t.metzger@intel.com>
> Subject: Re: [PATCH v11 10/10] btrace: Extend ptwrite event decoding.
> 
> > From: Felix Willgerodt <felix.willgerodt@intel.com>
> > Date: Thu, 25 Jul 2024 11:09:37 +0200
> >
> > Call the ptwrite filter function whenever a ptwrite event is decoded.
> > The returned string is written to the aux_data string table and a
> > corresponding auxiliary instruction is appended to the function segment.
> >
> > Reviewed-By: Eli Zaretskii <eliz@gnu.org>
> > Approved-By: Markus Metzger <markus.t.metzger@intel.com>
> > ---
> >  gdb/NEWS                                  |   7 +
> >  gdb/btrace.c                              |  45 ++
> >  gdb/config.in                             |   3 +
> >  gdb/configure                             |  11 +
> >  gdb/doc/python.texi                       | 149 ++++++
> >  gdb/testsuite/gdb.btrace/i386-ptwrite.S   | 550
> ++++++++++++++++++++++
> >  gdb/testsuite/gdb.btrace/ptwrite.c        |  39 ++
> >  gdb/testsuite/gdb.btrace/ptwrite.exp      | 202 ++++++++
> >  gdb/testsuite/gdb.btrace/x86_64-ptwrite.S | 544
> +++++++++++++++++++++
> >  gdb/testsuite/lib/gdb.exp                 |  72 +++
> >  gdbsupport/common.m4                      |   2 +
> >  gdbsupport/config.in                      |   3 +
> >  gdbsupport/configure                      |  11 +
> >  13 files changed, 1638 insertions(+)
> >  create mode 100644 gdb/testsuite/gdb.btrace/i386-ptwrite.S
> >  create mode 100644 gdb/testsuite/gdb.btrace/ptwrite.c
> >  create mode 100644 gdb/testsuite/gdb.btrace/ptwrite.exp
> >  create mode 100644 gdb/testsuite/gdb.btrace/x86_64-ptwrite.S
> 
> Thanks.
> 
> > +* GDB now supports printing of ptwrite payloads from the Intel Processor
> > +  Trace during 'record instruction-history', 'record function-call-history'
> > +  and all stepping commands.
> 
> The last sentence above reads as an incomplete sentence.

To me this is a proper English sentence. Could you elaborate on this or
propose a fix?

> > +If an inferior uses the instruction, @value{GDBN} by default inserts the
> > +raw payload value as auxiliary information into the execution history.
> > +Auxiliary information is by default printed during
> > +@code{record instruction-history}, @code{record function-call-history},
> > +and all stepping commands, and is accessible in Python as a
> > +@code{RecordAuxiliary} object.
> 
> What is the RecordAuxiliary object?  Is it described in the manual?

Yes it is. Patch 5 of this series adds it.

> And I think this could benefit from a cross-reference to where "record
> instruction-history" and "record function-call-history" are described.
> 

There is already a cross reference to the right section in this subsection,
just above the text you quoted:

+@code{PTWRITE} is a x86
+instruction that allows to write values into the Intel Processor Trace
+(@pxref{Process Record and Replay}).

I don't really see a point in adding the exact same reference again so
shortly after the first one. Especially as it is the same subsection.

Thanks for the review,
Felix


Intel Deutschland GmbH
Registered Address: Am Campeon 10, 85579 Neubiberg, Germany
Tel: +49 89 99 8853-0, www.intel.de
Managing Directors: Sean Fennelly, Jeffrey Schneiderman, Tiffany Doon Silva
Chairperson of the Supervisory Board: Nicole Lau
Registered Office: Munich
Commercial Register: Amtsgericht Muenchen HRB 186928
  
Eli Zaretskii July 25, 2024, 2:33 p.m. UTC | #3
> From: "Willgerodt, Felix" <felix.willgerodt@intel.com>
> CC: "gdb-patches@sourceware.org" <gdb-patches@sourceware.org>, "Metzger,
>  Markus T" <markus.t.metzger@intel.com>
> Date: Thu, 25 Jul 2024 12:15:33 +0000
> 
> > > +* GDB now supports printing of ptwrite payloads from the Intel Processor
> > > +  Trace during 'record instruction-history', 'record function-call-history'
> > > +  and all stepping commands.
> > 
> > The last sentence above reads as an incomplete sentence.
> 
> To me this is a proper English sentence. Could you elaborate on this or
> propose a fix?

I'm not sure I understand the sentence, so I cannot really propose a
better wording.  What did you mean by "Trace during"? is "trace" there
a verb or a noun?

> > > +If an inferior uses the instruction, @value{GDBN} by default inserts the
> > > +raw payload value as auxiliary information into the execution history.
> > > +Auxiliary information is by default printed during
> > > +@code{record instruction-history}, @code{record function-call-history},
> > > +and all stepping commands, and is accessible in Python as a
> > > +@code{RecordAuxiliary} object.
> > 
> > What is the RecordAuxiliary object?  Is it described in the manual?
> 
> Yes it is. Patch 5 of this series adds it.

Then please add a cross-reference to where it is/will be described.

> > And I think this could benefit from a cross-reference to where "record
> > instruction-history" and "record function-call-history" are described.
> > 
> 
> There is already a cross reference to the right section in this subsection,
> just above the text you quoted:
> 
> +@code{PTWRITE} is a x86
> +instruction that allows to write values into the Intel Processor Trace
> +(@pxref{Process Record and Replay}).
> 
> I don't really see a point in adding the exact same reference again so
> shortly after the first one. Especially as it is the same subsection.

In that case, no, another cross-reference is not needed there.
  
Metzger, Markus T July 25, 2024, 2:52 p.m. UTC | #4
Hello Felix,


>+	    if (btinfo->ptw_callback_fun != nullptr)
>+	      ptw_string
>+		= btinfo->ptw_callback_fun (event.variant.ptwrite.payload,
>+					    ip, btinfo->ptw_context);
>+
>+	    if (ptw_string.has_value () && (*ptw_string).empty ())
>+	      continue;
>+
>+	    if (!ptw_string.has_value ())
>+	      *ptw_string = hex_string (event.variant.ptwrite.payload);

Now I see why we want to distinguish an empty string from not a string.

Couldn't we instead use btinfo->ptw_callback_fun == nullptr?

If there is a filter and it wanted to print the raw value, it could just return
a string with the raw value instead of returning None and having GDB fill
in the raw value.

Regards,
Markus.
Intel Deutschland GmbH
Registered Address: Am Campeon 10, 85579 Neubiberg, Germany
Tel: +49 89 99 8853-0, www.intel.de
Managing Directors: Sean Fennelly, Jeffrey Schneiderman, Tiffany Doon Silva
Chairperson of the Supervisory Board: Nicole Lau
Registered Office: Munich
Commercial Register: Amtsgericht Muenchen HRB 186928
  
Willgerodt, Felix July 25, 2024, 2:53 p.m. UTC | #5
> -----Original Message-----
> From: Eli Zaretskii <eliz@gnu.org>
> Sent: Donnerstag, 25. Juli 2024 16:34
> To: Willgerodt, Felix <felix.willgerodt@intel.com>
> Cc: gdb-patches@sourceware.org; Metzger, Markus T
> <markus.t.metzger@intel.com>
> Subject: Re: [PATCH v11 10/10] btrace: Extend ptwrite event decoding.
> 
> > From: "Willgerodt, Felix" <felix.willgerodt@intel.com>
> > CC: "gdb-patches@sourceware.org" <gdb-patches@sourceware.org>,
> "Metzger,
> >  Markus T" <markus.t.metzger@intel.com>
> > Date: Thu, 25 Jul 2024 12:15:33 +0000
> >
> > > > +* GDB now supports printing of ptwrite payloads from the Intel Processor
> > > > +  Trace during 'record instruction-history', 'record function-call-history'
> > > > +  and all stepping commands.
> > >
> > > The last sentence above reads as an incomplete sentence.
> >
> > To me this is a proper English sentence. Could you elaborate on this or
> > propose a fix?
> 
> I'm not sure I understand the sentence, so I cannot really propose a
> better wording.  What did you mean by "Trace during"? is "trace" there
> a verb or a noun?

"Intel Processor Trace" is the name of a CPU feature. It is what the GDB
command "record btrace pt" uses to record the program.
Note that there are different types of recording formats/traces on some x86 CPUs.
They are already mentioned in the manual:
https://sourceware.org/gdb/current/onlinedocs/gdb.html/Process-Record-and-Replay.html


> > > > +If an inferior uses the instruction, @value{GDBN} by default inserts the
> > > > +raw payload value as auxiliary information into the execution history.
> > > > +Auxiliary information is by default printed during
> > > > +@code{record instruction-history}, @code{record function-call-history},
> > > > +and all stepping commands, and is accessible in Python as a
> > > > +@code{RecordAuxiliary} object.
> > >
> > > What is the RecordAuxiliary object?  Is it described in the manual?
> >
> > Yes it is. Patch 5 of this series adds it.
> 
> Then please add a cross-reference to where it is/will be described.

I will add one.

Thanks,
Felix
Intel Deutschland GmbH
Registered Address: Am Campeon 10, 85579 Neubiberg, Germany
Tel: +49 89 99 8853-0, www.intel.de
Managing Directors: Sean Fennelly, Jeffrey Schneiderman, Tiffany Doon Silva
Chairperson of the Supervisory Board: Nicole Lau
Registered Office: Munich
Commercial Register: Amtsgericht Muenchen HRB 186928
  
Eli Zaretskii July 25, 2024, 3:10 p.m. UTC | #6
> From: "Willgerodt, Felix" <felix.willgerodt@intel.com>
> CC: "gdb-patches@sourceware.org" <gdb-patches@sourceware.org>, "Metzger,
>  Markus T" <markus.t.metzger@intel.com>
> Date: Thu, 25 Jul 2024 14:53:18 +0000
> 
> > > > > +* GDB now supports printing of ptwrite payloads from the Intel Processor
> > > > > +  Trace during 'record instruction-history', 'record function-call-history'
> > > > > +  and all stepping commands.
> > > >
> > > > The last sentence above reads as an incomplete sentence.
> > >
> > > To me this is a proper English sentence. Could you elaborate on this or
> > > propose a fix?
> > 
> > I'm not sure I understand the sentence, so I cannot really propose a
> > better wording.  What did you mean by "Trace during"? is "trace" there
> > a verb or a noun?
> 
> "Intel Processor Trace" is the name of a CPU feature. It is what the GDB
> command "record btrace pt" uses to record the program.

Sorry, for some reason I thought that the first line ends in a period.
My bad.  There's nothing wrong with that NEWS patch.
  
Willgerodt, Felix July 26, 2024, 9:11 a.m. UTC | #7
> -----Original Message-----
> From: Metzger, Markus T <markus.t.metzger@intel.com>
> Sent: Donnerstag, 25. Juli 2024 16:53
> To: Willgerodt, Felix <felix.willgerodt@intel.com>; gdb-
> patches@sourceware.org
> Subject: RE: [PATCH v11 10/10] btrace: Extend ptwrite event decoding.
> 
> Hello Felix,
> 
> 
> >+	    if (btinfo->ptw_callback_fun != nullptr)
> >+	      ptw_string
> >+		= btinfo->ptw_callback_fun (event.variant.ptwrite.payload,
> >+					    ip, btinfo->ptw_context);
> >+
> >+	    if (ptw_string.has_value () && (*ptw_string).empty ())
> >+	      continue;
> >+
> >+	    if (!ptw_string.has_value ())
> >+	      *ptw_string = hex_string (event.variant.ptwrite.payload);
> 
> Now I see why we want to distinguish an empty string from not a string.
> 
> Couldn't we instead use btinfo->ptw_callback_fun == nullptr?
> 
> If there is a filter and it wanted to print the raw value, it could just return
> a string with the raw value instead of returning None and having GDB fill
> in the raw value.
> 
> Regards,
> Markus.

This was mainly added based on feedback from Simon last year:
https://inbox.sourceware.org/gdb-patches/9c1d4088-3a18-d806-5320-b554abc7f0d1@simark.ca/
The main advantage I see is supporting this for a GDB build without python.
And that the user doesn't have to register anything himself for the default behaviour.
If he wants to disable payload printing, he can use the /a option, or if he wants to see some other
aux options but not ptwrite, register a filter that returns an empty string. Simon's idea was also to
register None as a means to reset the behaviour of GDB back to the default one.
Instead of silencing output.

Regards,
Felix
Intel Deutschland GmbH
Registered Address: Am Campeon 10, 85579 Neubiberg, Germany
Tel: +49 89 99 8853-0, www.intel.de
Managing Directors: Sean Fennelly, Jeffrey Schneiderman, Tiffany Doon Silva
Chairperson of the Supervisory Board: Nicole Lau
Registered Office: Munich
Commercial Register: Amtsgericht Muenchen HRB 186928
  
Metzger, Markus T Aug. 7, 2024, 11:48 a.m. UTC | #8
Hello Felix,

>+#include <immintrin.h>
>+
>+void
>+ptwrite1 (int value)
>+{
>+  _ptwrite32 (value);
>+}

Why is the test case not using the GCC builtin functions from the documentation?
Should the documentation be updated to use those _ptwrite wrappers?

>+set opts {}

Wouldn't we need to add 'debug'?  It's the default, but we pass options explicitly.
Since pre-compiled assembly sources already contain debug info, this probably
only shows with COMPILE=1.

The test checks for specific instructions at specific locations in the trace so COMPILE=1
probably won't pass, anyway.

>+# Setup recording
>+gdb_test_no_output "set record instruction-history-size unlimited"
>+gdb_test_no_output "record btrace pt"
>+gdb_test "next" ".*" "next"
>+gdb_test "next" ".*" "next 2"

We could use 'next 2' so we don't need an explicit message.

>+# Run a test on the target to see if it supports ptwrite instructions and
>+# if GDB can decode ptwrite events.  Return 1 if so, 0 if it does not.
>+
>+gdb_caching_proc allow_btrace_ptw_tests {} {
>+    global srcdir subdir gdb_prompt inferior_exited_re decimal
>+
>+    require allow_btrace_pt_tests
>+    set me "allow_btrace_ptw_tests"
>+
>+    set src {
>+	int
>+	main ()
>+	{
>+	  asm volatile ("PTWRITE %0;" : : "b"(0x42));

This is yet another way of encoding ptwrite instructions.  I think we should
align on one and use it everywhere.

>+    if { $allow_btrace_ptw_tests == 1 } {
>+	# Show the func-call-history to get the packet trace.
>+	gdb_test "record function-call-history" ".*"
>+
>+	gdb_test_multiple "maintenance btrace packet-history 0,1000" \
>+	    "$me: check decoding support" {
>+	    -re  "ptw" {
>+		verbose -log "$me:  ptwrite decoding support detected."
>+		set allow_btrace_ptw_tests 1
>+	    }
>+	    -re ".*${gdb_prompt} $" {
>+		verbose -log "$me:  ptwrite decoding support not detected."
>+		set allow_btrace_ptw_tests 0
>+	    }

This is the only place where we use gdb_prompt.  Wouldn't '-re -wrap ""' work?

>+	}
>+    }
>+
>+    gdb_exit
>+    remote_file build delete $obj
>+
>+    verbose "$me:  returning $allow_btrace_ptw_tests" 2
>+    return $allow_btrace_ptw_tests

This was initialized to 2.  If those gdb_test_multiple time out, we would end up
returning 2, which is probably interpreted as 'allowed'.

Regards,
Markus.
Intel Deutschland GmbH
Registered Address: Am Campeon 10, 85579 Neubiberg, Germany
Tel: +49 89 99 8853-0, www.intel.de
Managing Directors: Sean Fennelly, Jeffrey Schneiderman, Tiffany Doon Silva
Chairperson of the Supervisory Board: Nicole Lau
Registered Office: Munich
Commercial Register: Amtsgericht Muenchen HRB 186928
  
Willgerodt, Felix Aug. 12, 2024, 2:14 p.m. UTC | #9
> -----Original Message-----
> From: Metzger, Markus T <markus.t.metzger@intel.com>
> Sent: Mittwoch, 7. August 2024 13:49
> To: Willgerodt, Felix <felix.willgerodt@intel.com>
> Cc: gdb-patches@sourceware.org
> Subject: RE: [PATCH v11 10/10] btrace: Extend ptwrite event decoding.
> 
> Hello Felix,
> 
> >+#include <immintrin.h>
> >+
> >+void
> >+ptwrite1 (int value)
> >+{
> >+  _ptwrite32 (value);
> >+}
> 
> Why is the test case not using the GCC builtin functions from the documentation?
> Should the documentation be updated to use those _ptwrite wrappers?

Historically grown. _ptwrite32/64() is from the Intel intrinsics guide and should work
with all compilers (including GCC) and is shorter. I will update the documentation to use that.

> >+set opts {}
> 
> Wouldn't we need to add 'debug'?  It's the default, but we pass options explicitly.
> Since pre-compiled assembly sources already contain debug info, this probably
> only shows with COMPILE=1.
> 
> The test checks for specific instructions at specific locations in the trace so
> COMPILE=1
> probably won't pass, anyway.

I just copied this from other tests. And in the case of COMPILE=1, we do pass
'debug'. For the disassembly file case, we already have symbols as you said.
So both cases are covered and have symbols.

FWIW: I see COMPILE=1 working fine (all passes, no failures) on a machine
that has a different GCC (gcc 15) than the one I used to create the assembly
files (GCC 10). But yes there could of course be differences. But I think that
is the intention of the whole mechanism.

> >+# Setup recording
> >+gdb_test_no_output "set record instruction-history-size unlimited"
> >+gdb_test_no_output "record btrace pt"
> >+gdb_test "next" ".*" "next"
> >+gdb_test "next" ".*" "next 2"
> 
> We could use 'next 2' so we don't need an explicit message.

Good idea, will do.

> >+# Run a test on the target to see if it supports ptwrite instructions and
> >+# if GDB can decode ptwrite events.  Return 1 if so, 0 if it does not.
> >+
> >+gdb_caching_proc allow_btrace_ptw_tests {} {
> >+    global srcdir subdir gdb_prompt inferior_exited_re decimal
> >+
> >+    require allow_btrace_pt_tests
> >+    set me "allow_btrace_ptw_tests"
> >+
> >+    set src {
> >+	int
> >+	main ()
> >+	{
> >+	  asm volatile ("PTWRITE %0;" : : "b"(0x42));
> 
> This is yet another way of encoding ptwrite instructions.  I think we should
> align on one and use it everywhere.

Will do.

> >+    if { $allow_btrace_ptw_tests == 1 } {
> >+	# Show the func-call-history to get the packet trace.
> >+	gdb_test "record function-call-history" ".*"
> >+
> >+	gdb_test_multiple "maintenance btrace packet-history 0,1000" \
> >+	    "$me: check decoding support" {
> >+	    -re  "ptw" {
> >+		verbose -log "$me:  ptwrite decoding support detected."
> >+		set allow_btrace_ptw_tests 1
> >+	    }
> >+	    -re ".*${gdb_prompt} $" {
> >+		verbose -log "$me:  ptwrite decoding support not detected."
> >+		set allow_btrace_ptw_tests 0
> >+	    }
> 
> This is the only place where we use gdb_prompt.  Wouldn't '-re -wrap ""' work?

It does work. Will change.

> >+	}
> >+    }
> >+
> >+    gdb_exit
> >+    remote_file build delete $obj
> >+
> >+    verbose "$me:  returning $allow_btrace_ptw_tests" 2
> >+    return $allow_btrace_ptw_tests
> 
> This was initialized to 2.  If those gdb_test_multiple time out, we would end up
> returning 2, which is probably interpreted as 'allowed'.

Right, will fix.

Sorry, I forgot to send out this answer with my v12 series.
Felix
Intel Deutschland GmbH
Registered Address: Am Campeon 10, 85579 Neubiberg, Germany
Tel: +49 89 99 8853-0, www.intel.de
Managing Directors: Sean Fennelly, Jeffrey Schneiderman, Tiffany Doon Silva
Chairperson of the Supervisory Board: Nicole Lau
Registered Office: Munich
Commercial Register: Amtsgericht Muenchen HRB 186928
  

Patch

diff --git a/gdb/NEWS b/gdb/NEWS
index 4ab6cc92edf..00da390f214 100644
--- a/gdb/NEWS
+++ b/gdb/NEWS
@@ -3,6 +3,13 @@ 
 
 *** Changes since GDB 15
 
+* GDB now supports printing of ptwrite payloads from the Intel Processor
+  Trace during 'record instruction-history', 'record function-call-history'
+  and all stepping commands.  The payload is also accessible in Python as a
+  RecordAuxiliary object.  Printing is customizable via a ptwrite filter
+  function in Python.  By default, the raw ptwrite payload is printed for
+  each ptwrite that is encountered.
+
 * Python API
 
   ** Added gdb.record.clear(). Clears the trace data of the current recording.
diff --git a/gdb/btrace.c b/gdb/btrace.c
index 92d371d1da9..9d60096f985 100644
--- a/gdb/btrace.c
+++ b/gdb/btrace.c
@@ -41,6 +41,7 @@ 
 #include <inttypes.h>
 #include <ctype.h>
 #include <algorithm>
+#include <string>
 
 /* Command lists for btrace maintenance commands.  */
 static struct cmd_list_element *maint_btrace_cmdlist;
@@ -1205,6 +1206,24 @@  pt_btrace_insn (const struct pt_insn &insn)
 	  pt_btrace_insn_flags (insn)};
 }
 
+#if defined (HAVE_PT_INSN_EVENT)
+/* Helper for events that will result in an aux_insn.  */
+
+static void
+handle_pt_aux_insn (btrace_thread_info *btinfo, btrace_function *bfun,
+		    std::string &aux_str, CORE_ADDR ip)
+{
+  btinfo->aux_data.emplace_back (std::move (aux_str));
+  bfun = ftrace_update_function (btinfo, ip);
+
+  btrace_insn insn {btinfo->aux_data.size () - 1, 0,
+		    BTRACE_INSN_AUX, 0};
+
+  ftrace_update_insns (bfun, insn);
+}
+
+#endif /* defined (HAVE_PT_INSN_EVENT) */
+
 /* Handle instruction decode events (libipt-v2).  */
 
 static int
@@ -1253,6 +1272,32 @@  handle_pt_insn_events (struct btrace_thread_info *btinfo,
 		   bfun->insn_offset - 1, offset);
 
 	  break;
+#if defined (HAVE_STRUCT_PT_EVENT_VARIANT_PTWRITE)
+	case ptev_ptwrite:
+	  {
+	    uint64_t ip = 0;
+	    std::optional<std::string> ptw_string;
+
+	    /* Lookup the ip if available.  */
+	    if (event.ip_suppressed == 0)
+	      ip = event.variant.ptwrite.ip;
+
+	    if (btinfo->ptw_callback_fun != nullptr)
+	      ptw_string
+		= btinfo->ptw_callback_fun (event.variant.ptwrite.payload,
+					    ip, btinfo->ptw_context);
+
+	    if (ptw_string.has_value () && (*ptw_string).empty ())
+	      continue;
+
+	    if (!ptw_string.has_value ())
+	      *ptw_string = hex_string (event.variant.ptwrite.payload);
+
+	    handle_pt_aux_insn (btinfo, bfun, *ptw_string, ip);
+
+	    break;
+	  }
+#endif /* defined (HAVE_STRUCT_PT_EVENT_VARIANT_PTWRITE) */
 	}
     }
 #endif /* defined (HAVE_PT_INSN_EVENT) */
diff --git a/gdb/config.in b/gdb/config.in
index 0c144c8918b..57be033802e 100644
--- a/gdb/config.in
+++ b/gdb/config.in
@@ -481,6 +481,9 @@ 
 /* Define to 1 if `pl_tdname' is a member of `struct ptrace_lwpinfo'. */
 #undef HAVE_STRUCT_PTRACE_LWPINFO_PL_TDNAME
 
+/* Define to 1 if `variant.ptwrite' is a member of `struct pt_event'. */
+#undef HAVE_STRUCT_PT_EVENT_VARIANT_PTWRITE
+
 /* Define to 1 if `enabled' is a member of `struct pt_insn'. */
 #undef HAVE_STRUCT_PT_INSN_ENABLED
 
diff --git a/gdb/configure b/gdb/configure
index 15ececfefa2..ce9a957f44c 100755
--- a/gdb/configure
+++ b/gdb/configure
@@ -21510,6 +21510,17 @@  cat >>confdefs.h <<_ACEOF
 _ACEOF
 
 
+fi
+
+      ac_fn_c_check_member "$LINENO" "struct pt_event" "variant.ptwrite" "ac_cv_member_struct_pt_event_variant_ptwrite" "#include <intel-pt.h>
+"
+if test "x$ac_cv_member_struct_pt_event_variant_ptwrite" = xyes; then :
+
+cat >>confdefs.h <<_ACEOF
+#define HAVE_STRUCT_PT_EVENT_VARIANT_PTWRITE 1
+_ACEOF
+
+
 fi
 
       LIBS=$save_LIBS
diff --git a/gdb/doc/python.texi b/gdb/doc/python.texi
index ac6015b3c2e..953734fda46 100644
--- a/gdb/doc/python.texi
+++ b/gdb/doc/python.texi
@@ -8224,6 +8224,7 @@  registering objfile-specific pretty-printers and frame-filters.
 * gdb.printing::       Building and registering pretty-printers.
 * gdb.types::          Utilities for working with types.
 * gdb.prompt::         Utilities for prompt value substitution.
+* gdb.ptwrite::        Utilities for PTWRITE filter registration.
 @end menu
 
 @node gdb.printing
@@ -8414,3 +8415,151 @@  substitute_prompt ("frame: \f, args: \p@{print frame-arguments@}")
 "frame: main, args: scalars"
 @end smallexample
 @end table
+
+@node gdb.ptwrite
+@subsubsection gdb.ptwrite
+@cindex gdb.ptwrite
+
+This module provides additional functionality for recording programs that
+make use of the @code{PTWRITE} instruction.  @code{PTWRITE} is a x86
+instruction that allows to write values into the Intel Processor Trace
+(@pxref{Process Record and Replay}).
+The @value{NGCC} built-in functions for it are:
+@smallexample
+void __builtin_ia32_ptwrite32 (unsigned);
+void __builtin_ia32_ptwrite64 (unsigned long long);
+@end smallexample
+
+If an inferior uses the instruction, @value{GDBN} by default inserts the
+raw payload value as auxiliary information into the execution history.
+Auxiliary information is by default printed during
+@code{record instruction-history}, @code{record function-call-history},
+and all stepping commands, and is accessible in Python as a
+@code{RecordAuxiliary} object.
+
+@exdent Sample program:
+@smallexample
+@group
+void
+ptwrite64 (unsigned long long value)
+@{
+  __builtin_ia32_ptwrite64 (value);
+@}
+@end group
+
+@group
+int
+main (void)
+@{
+  ptwrite64 (0x42);
+  return 0; /* break here.  */
+@}
+@end group
+@end smallexample
+
+
+@exdent @value{GDBN} output after recording the sample program in pt format:
+@smallexample
+@group
+(gdb) record instruction-history 12,14
+12         0x0040074c <ptwrite64+16>:   ptwrite %rbx
+13           [0x42]
+14         0x00400751 <ptwrite64+21>:   mov -0x8(%rbp),%rbx
+(gdb) record function-call-history
+1       main
+2       ptwrite64
+          [0x42]
+3       main
+@end group
+@end smallexample
+
+The @code{gdb.ptwrite} module allows customizing the default output of
+@code{PTWRITE} auxiliary information.  A custom Python function can be
+registered as the @code{PTWRITE} filter function.  This function will be
+called with the @code{PTWRITE} payload and PC as arguments during trace
+decoding.  It can return a string, which will be printed by @value{GDBN}
+during the aforementioned commands, or @code{None}, resulting in no output.
+To register such a filter function, the user needs to provide a filter factory
+function, which returns a new filter function object to be called by
+@value{GDBN}.
+
+@findex gdb.ptwrite.register_filter_factory
+@defun register_filter_factory (filter_factory)
+Used to register the @code{PTWRITE} filter factory.  This filter factory can
+be any callable object that accepts one argument, the current thread as
+a @code{gdb.InferiorThread}.
+It can return None or a callable.  This callable is the @code{PTWRITE} filter
+function for the specified thread.  If @code{None} is returned by the factory
+function, the default auxiliary information will be printed.
+@end defun
+
+@findex gdb.ptwrite.get_filter
+@defun get_filter ()
+Return the currently active @code{PTWRITE} filter function.
+@end defun
+
+An example:
+
+@smallexample
+@group
+(gdb) python-interactive
+>>> class my_filter():
+...    def __init__(self):
+...        self.var = 0
+...    def __call__(self, payload, ip):
+...        self.var += 1
+...        return f"counter: @{self.var@}, ip: @{ip:#x@}"
+...
+>>> def my_filter_factory(thread):
+...    if thread.global_num == 1:
+...        return my_filter()
+...    else:
+...        return None
+...
+>>> import gdb.ptwrite
+>>> gdb.ptwrite.register_filter_factory(my_filter_factory)
+>>>
+@end group
+
+@group
+(gdb) record function-call-history 59,64
+59      pthread_create@@GLIBC_2.2.5
+60      job()
+61      task(void*)
+62      ptwrite64(unsigned long)
+          [counter: 1, ip: 0x401156]
+63      task(void*)
+64      ptwrite32(unsigned int)
+          [counter: 2, ip: 0x40116c]
+@end group
+
+@group
+(gdb) info threads
+* 1    Thread 0x7ffff7fd8740 (LWP 25796) "ptw_threads" task ()
+    at bin/ptwrite/ptw_threads.c:45
+  2    Thread 0x7ffff6eb8700 (LWP 25797) "ptw_threads" task ()
+    at bin/ptwrite/ptw_threads.c:45
+@end group
+
+@group
+(gdb) thread 2
+[Switching to thread 2 (Thread 0x7ffff6eb8700 (LWP 25797))]
+#0  task (arg=0x0) at ptwrite_threads.c:45
+45        return NULL;
+@end group
+
+@group
+(gdb) record function-call-history 10,14
+10    start_thread
+11    task(void*)
+12    ptwrite64(unsigned long)
+        [0x42]
+13    task(void*)
+14    ptwrite32(unsigned int)
+        [0x43]
+@end group
+@end smallexample
+
+This @value{GDBN} feature is dependent on hardware and operating system
+support and requires the Intel Processor Trace decoder library in version
+2.0.0 or newer.
diff --git a/gdb/testsuite/gdb.btrace/i386-ptwrite.S b/gdb/testsuite/gdb.btrace/i386-ptwrite.S
new file mode 100644
index 00000000000..5c649cf194a
--- /dev/null
+++ b/gdb/testsuite/gdb.btrace/i386-ptwrite.S
@@ -0,0 +1,550 @@ 
+/* This testcase is part of GDB, the GNU debugger.
+
+   Copyright 2024 Free Software Foundation, Inc.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+
+   This file has been generated using gcc version 10.3.1 20210422
+   (Red Hat 10.3.1-1):
+   gcc -S -dA -g -m32 -mptwrite ptwrite.c -o i386-ptwrite.S.  */
+
+
+	.file	"ptwrite.c"
+	.text
+.Ltext0:
+	.globl	ptwrite1
+	.type	ptwrite1, @function
+ptwrite1:
+.LFB4021:
+	.file 1 "ptwrite.c"
+	# ptwrite.c:22:1
+	.loc 1 22 1
+	.cfi_startproc
+# BLOCK 2 seq:0
+# PRED: ENTRY (FALLTHRU)
+	pushl	%ebp
+	.cfi_def_cfa_offset 8
+	.cfi_offset 5, -8
+	movl	%esp, %ebp
+	.cfi_def_cfa_register 5
+	subl	$16, %esp
+	# ptwrite.c:23:3
+	.loc 1 23 3
+	movl	8(%ebp), %eax
+	movl	%eax, -4(%ebp)
+.LBB6:
+.LBB7:
+	.file 2 "/usr/lib/gcc/x86_64-redhat-linux/10/include/immintrin.h"
+	# /usr/lib/gcc/x86_64-redhat-linux/10/include/immintrin.h:307:3
+	.loc 2 307 3
+	movl	-4(%ebp), %eax
+	ptwrite	%eax
+	# /usr/lib/gcc/x86_64-redhat-linux/10/include/immintrin.h:308:1
+	.loc 2 308 1
+	nop
+.LBE7:
+.LBE6:
+	# ptwrite.c:24:1
+	.loc 1 24 1
+	nop
+	leave
+	.cfi_restore 5
+	.cfi_def_cfa 4, 4
+# SUCC: EXIT [always]
+	ret
+	.cfi_endproc
+.LFE4021:
+	.size	ptwrite1, .-ptwrite1
+	.globl	ptwrite2
+	.type	ptwrite2, @function
+ptwrite2:
+.LFB4022:
+	# ptwrite.c:28:1
+	.loc 1 28 1
+	.cfi_startproc
+# BLOCK 2 seq:0
+# PRED: ENTRY (FALLTHRU)
+	pushl	%ebp
+	.cfi_def_cfa_offset 8
+	.cfi_offset 5, -8
+	movl	%esp, %ebp
+	.cfi_def_cfa_register 5
+	subl	$16, %esp
+	# ptwrite.c:29:3
+	.loc 1 29 3
+	movl	8(%ebp), %eax
+	movl	%eax, -4(%ebp)
+.LBB8:
+.LBB9:
+	# /usr/lib/gcc/x86_64-redhat-linux/10/include/immintrin.h:307:3
+	.loc 2 307 3
+	movl	-4(%ebp), %eax
+	ptwrite	%eax
+	# /usr/lib/gcc/x86_64-redhat-linux/10/include/immintrin.h:308:1
+	.loc 2 308 1
+	nop
+.LBE9:
+.LBE8:
+	# ptwrite.c:30:1
+	.loc 1 30 1
+	nop
+	leave
+	.cfi_restore 5
+	.cfi_def_cfa 4, 4
+# SUCC: EXIT [always]
+	ret
+	.cfi_endproc
+.LFE4022:
+	.size	ptwrite2, .-ptwrite2
+	.globl	main
+	.type	main, @function
+main:
+.LFB4023:
+	# ptwrite.c:34:1
+	.loc 1 34 1
+	.cfi_startproc
+# BLOCK 2 seq:0
+# PRED: ENTRY (FALLTHRU)
+	pushl	%ebp
+	.cfi_def_cfa_offset 8
+	.cfi_offset 5, -8
+	movl	%esp, %ebp
+	.cfi_def_cfa_register 5
+	# ptwrite.c:35:3
+	.loc 1 35 3
+	pushl	$66
+	call	ptwrite1
+	addl	$4, %esp
+	# ptwrite.c:36:3
+	.loc 1 36 3
+	pushl	$67
+	call	ptwrite2
+	addl	$4, %esp
+	# ptwrite.c:38:10
+	.loc 1 38 10
+	movl	$0, %eax
+	# ptwrite.c:39:1
+	.loc 1 39 1
+	leave
+	.cfi_restore 5
+	.cfi_def_cfa 4, 4
+# SUCC: EXIT [always]
+	ret
+	.cfi_endproc
+.LFE4023:
+	.size	main, .-main
+.Letext0:
+	.section	.debug_info,"",@progbits
+.Ldebug_info0:
+	.long	0x129	# Length of Compilation Unit Info
+	.value	0x4	# DWARF version number
+	.long	.Ldebug_abbrev0	# Offset Into Abbrev. Section
+	.byte	0x4	# Pointer Size (in bytes)
+	.uleb128 0x1	# (DIE (0xb) DW_TAG_compile_unit)
+	.long	.LASF15	# DW_AT_producer: "GNU C17 10.3.1 20210422 (Red Hat 10.3.1-1) -m32 -mptwrite -mtune=generic -march=i686 -g"
+	.byte	0xc	# DW_AT_language
+	.long	.LASF16	# DW_AT_name: "ptwrite.c"
+	.long	.LASF17	# DW_AT_comp_dir: "gdb/gdb/testsuite/gdb.btrace"
+	.long	.Ltext0	# DW_AT_low_pc
+	.long	.Letext0-.Ltext0	# DW_AT_high_pc
+	.long	.Ldebug_line0	# DW_AT_stmt_list
+	.uleb128 0x2	# (DIE (0x25) DW_TAG_base_type)
+	.byte	0x4	# DW_AT_byte_size
+	.byte	0x5	# DW_AT_encoding
+	.ascii "int\0"	# DW_AT_name
+	.uleb128 0x3	# (DIE (0x2c) DW_TAG_base_type)
+	.byte	0x2	# DW_AT_byte_size
+	.byte	0x5	# DW_AT_encoding
+	.long	.LASF0	# DW_AT_name: "short int"
+	.uleb128 0x3	# (DIE (0x33) DW_TAG_base_type)
+	.byte	0x1	# DW_AT_byte_size
+	.byte	0x6	# DW_AT_encoding
+	.long	.LASF1	# DW_AT_name: "char"
+	.uleb128 0x3	# (DIE (0x3a) DW_TAG_base_type)
+	.byte	0x8	# DW_AT_byte_size
+	.byte	0x5	# DW_AT_encoding
+	.long	.LASF2	# DW_AT_name: "long long int"
+	.uleb128 0x3	# (DIE (0x41) DW_TAG_base_type)
+	.byte	0x4	# DW_AT_byte_size
+	.byte	0x4	# DW_AT_encoding
+	.long	.LASF3	# DW_AT_name: "float"
+	.uleb128 0x3	# (DIE (0x48) DW_TAG_base_type)
+	.byte	0x4	# DW_AT_byte_size
+	.byte	0x7	# DW_AT_encoding
+	.long	.LASF4	# DW_AT_name: "unsigned int"
+	.uleb128 0x3	# (DIE (0x4f) DW_TAG_base_type)
+	.byte	0x4	# DW_AT_byte_size
+	.byte	0x5	# DW_AT_encoding
+	.long	.LASF5	# DW_AT_name: "long int"
+	.uleb128 0x3	# (DIE (0x56) DW_TAG_base_type)
+	.byte	0x1	# DW_AT_byte_size
+	.byte	0x8	# DW_AT_encoding
+	.long	.LASF6	# DW_AT_name: "unsigned char"
+	.uleb128 0x3	# (DIE (0x5d) DW_TAG_base_type)
+	.byte	0x2	# DW_AT_byte_size
+	.byte	0x7	# DW_AT_encoding
+	.long	.LASF7	# DW_AT_name: "short unsigned int"
+	.uleb128 0x3	# (DIE (0x64) DW_TAG_base_type)
+	.byte	0x4	# DW_AT_byte_size
+	.byte	0x7	# DW_AT_encoding
+	.long	.LASF8	# DW_AT_name: "long unsigned int"
+	.uleb128 0x3	# (DIE (0x6b) DW_TAG_base_type)
+	.byte	0x1	# DW_AT_byte_size
+	.byte	0x6	# DW_AT_encoding
+	.long	.LASF9	# DW_AT_name: "signed char"
+	.uleb128 0x3	# (DIE (0x72) DW_TAG_base_type)
+	.byte	0x8	# DW_AT_byte_size
+	.byte	0x7	# DW_AT_encoding
+	.long	.LASF10	# DW_AT_name: "long long unsigned int"
+	.uleb128 0x3	# (DIE (0x79) DW_TAG_base_type)
+	.byte	0x8	# DW_AT_byte_size
+	.byte	0x4	# DW_AT_encoding
+	.long	.LASF11	# DW_AT_name: "double"
+	.uleb128 0x4	# (DIE (0x80) DW_TAG_subprogram)
+			# DW_AT_external
+	.long	.LASF18	# DW_AT_name: "main"
+	.byte	0x1	# DW_AT_decl_file (ptwrite.c)
+	.byte	0x21	# DW_AT_decl_line
+	.byte	0x1	# DW_AT_decl_column
+			# DW_AT_prototyped
+	.long	0x25	# DW_AT_type
+	.long	.LFB4023	# DW_AT_low_pc
+	.long	.LFE4023-.LFB4023	# DW_AT_high_pc
+	.uleb128 0x1	# DW_AT_frame_base
+	.byte	0x9c	# DW_OP_call_frame_cfa
+			# DW_AT_GNU_all_tail_call_sites
+	.uleb128 0x5	# (DIE (0x96) DW_TAG_subprogram)
+			# DW_AT_external
+	.long	.LASF12	# DW_AT_name: "ptwrite2"
+	.byte	0x1	# DW_AT_decl_file (ptwrite.c)
+	.byte	0x1b	# DW_AT_decl_line
+	.byte	0x1	# DW_AT_decl_column
+			# DW_AT_prototyped
+	.long	.LFB4022	# DW_AT_low_pc
+	.long	.LFE4022-.LFB4022	# DW_AT_high_pc
+	.uleb128 0x1	# DW_AT_frame_base
+	.byte	0x9c	# DW_OP_call_frame_cfa
+			# DW_AT_GNU_all_call_sites
+	.long	0xd5	# DW_AT_sibling
+	.uleb128 0x6	# (DIE (0xac) DW_TAG_formal_parameter)
+	.long	.LASF14	# DW_AT_name: "value"
+	.byte	0x1	# DW_AT_decl_file (ptwrite.c)
+	.byte	0x1b	# DW_AT_decl_line
+	.byte	0xf	# DW_AT_decl_column
+	.long	0x25	# DW_AT_type
+	.uleb128 0x2	# DW_AT_location
+	.byte	0x91	# DW_OP_fbreg
+	.sleb128 0
+	.uleb128 0x7	# (DIE (0xbb) DW_TAG_inlined_subroutine)
+	.long	0x114	# DW_AT_abstract_origin
+	.long	.LBB8	# DW_AT_low_pc
+	.long	.LBE8-.LBB8	# DW_AT_high_pc
+	.byte	0x1	# DW_AT_call_file (ptwrite.c)
+	.byte	0x1d	# DW_AT_call_line
+	.byte	0x3	# DW_AT_call_column
+	.uleb128 0x8	# (DIE (0xcb) DW_TAG_formal_parameter)
+	.long	0x11e	# DW_AT_abstract_origin
+	.uleb128 0x2	# DW_AT_location
+	.byte	0x91	# DW_OP_fbreg
+	.sleb128 -12
+	.byte	0	# end of children of DIE 0xbb
+	.byte	0	# end of children of DIE 0x96
+	.uleb128 0x5	# (DIE (0xd5) DW_TAG_subprogram)
+			# DW_AT_external
+	.long	.LASF13	# DW_AT_name: "ptwrite1"
+	.byte	0x1	# DW_AT_decl_file (ptwrite.c)
+	.byte	0x15	# DW_AT_decl_line
+	.byte	0x1	# DW_AT_decl_column
+			# DW_AT_prototyped
+	.long	.LFB4021	# DW_AT_low_pc
+	.long	.LFE4021-.LFB4021	# DW_AT_high_pc
+	.uleb128 0x1	# DW_AT_frame_base
+	.byte	0x9c	# DW_OP_call_frame_cfa
+			# DW_AT_GNU_all_call_sites
+	.long	0x114	# DW_AT_sibling
+	.uleb128 0x6	# (DIE (0xeb) DW_TAG_formal_parameter)
+	.long	.LASF14	# DW_AT_name: "value"
+	.byte	0x1	# DW_AT_decl_file (ptwrite.c)
+	.byte	0x15	# DW_AT_decl_line
+	.byte	0xf	# DW_AT_decl_column
+	.long	0x25	# DW_AT_type
+	.uleb128 0x2	# DW_AT_location
+	.byte	0x91	# DW_OP_fbreg
+	.sleb128 0
+	.uleb128 0x7	# (DIE (0xfa) DW_TAG_inlined_subroutine)
+	.long	0x114	# DW_AT_abstract_origin
+	.long	.LBB6	# DW_AT_low_pc
+	.long	.LBE6-.LBB6	# DW_AT_high_pc
+	.byte	0x1	# DW_AT_call_file (ptwrite.c)
+	.byte	0x17	# DW_AT_call_line
+	.byte	0x3	# DW_AT_call_column
+	.uleb128 0x8	# (DIE (0x10a) DW_TAG_formal_parameter)
+	.long	0x11e	# DW_AT_abstract_origin
+	.uleb128 0x2	# DW_AT_location
+	.byte	0x91	# DW_OP_fbreg
+	.sleb128 -12
+	.byte	0	# end of children of DIE 0xfa
+	.byte	0	# end of children of DIE 0xd5
+	.uleb128 0x9	# (DIE (0x114) DW_TAG_subprogram)
+			# DW_AT_external
+	.long	.LASF19	# DW_AT_name: "_ptwrite32"
+	.byte	0x2	# DW_AT_decl_file (/usr/lib/gcc/x86_64-redhat-linux/10/include/immintrin.h)
+	.value	0x131	# DW_AT_decl_line
+	.byte	0x1	# DW_AT_decl_column
+			# DW_AT_prototyped
+	.byte	0x3	# DW_AT_inline
+			# DW_AT_artificial
+	.uleb128 0xa	# (DIE (0x11e) DW_TAG_formal_parameter)
+	.ascii "__B\0"	# DW_AT_name
+	.byte	0x2	# DW_AT_decl_file (/usr/lib/gcc/x86_64-redhat-linux/10/include/immintrin.h)
+	.value	0x131	# DW_AT_decl_line
+	.byte	0x16	# DW_AT_decl_column
+	.long	0x48	# DW_AT_type
+	.byte	0	# end of children of DIE 0x114
+	.byte	0	# end of children of DIE 0xb
+	.section	.debug_abbrev,"",@progbits
+.Ldebug_abbrev0:
+	.uleb128 0x1	# (abbrev code)
+	.uleb128 0x11	# (TAG: DW_TAG_compile_unit)
+	.byte	0x1	# DW_children_yes
+	.uleb128 0x25	# (DW_AT_producer)
+	.uleb128 0xe	# (DW_FORM_strp)
+	.uleb128 0x13	# (DW_AT_language)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3	# (DW_AT_name)
+	.uleb128 0xe	# (DW_FORM_strp)
+	.uleb128 0x1b	# (DW_AT_comp_dir)
+	.uleb128 0xe	# (DW_FORM_strp)
+	.uleb128 0x11	# (DW_AT_low_pc)
+	.uleb128 0x1	# (DW_FORM_addr)
+	.uleb128 0x12	# (DW_AT_high_pc)
+	.uleb128 0x6	# (DW_FORM_data4)
+	.uleb128 0x10	# (DW_AT_stmt_list)
+	.uleb128 0x17	# (DW_FORM_sec_offset)
+	.byte	0
+	.byte	0
+	.uleb128 0x2	# (abbrev code)
+	.uleb128 0x24	# (TAG: DW_TAG_base_type)
+	.byte	0	# DW_children_no
+	.uleb128 0xb	# (DW_AT_byte_size)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3e	# (DW_AT_encoding)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3	# (DW_AT_name)
+	.uleb128 0x8	# (DW_FORM_string)
+	.byte	0
+	.byte	0
+	.uleb128 0x3	# (abbrev code)
+	.uleb128 0x24	# (TAG: DW_TAG_base_type)
+	.byte	0	# DW_children_no
+	.uleb128 0xb	# (DW_AT_byte_size)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3e	# (DW_AT_encoding)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3	# (DW_AT_name)
+	.uleb128 0xe	# (DW_FORM_strp)
+	.byte	0
+	.byte	0
+	.uleb128 0x4	# (abbrev code)
+	.uleb128 0x2e	# (TAG: DW_TAG_subprogram)
+	.byte	0	# DW_children_no
+	.uleb128 0x3f	# (DW_AT_external)
+	.uleb128 0x19	# (DW_FORM_flag_present)
+	.uleb128 0x3	# (DW_AT_name)
+	.uleb128 0xe	# (DW_FORM_strp)
+	.uleb128 0x3a	# (DW_AT_decl_file)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3b	# (DW_AT_decl_line)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x39	# (DW_AT_decl_column)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x27	# (DW_AT_prototyped)
+	.uleb128 0x19	# (DW_FORM_flag_present)
+	.uleb128 0x49	# (DW_AT_type)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.uleb128 0x11	# (DW_AT_low_pc)
+	.uleb128 0x1	# (DW_FORM_addr)
+	.uleb128 0x12	# (DW_AT_high_pc)
+	.uleb128 0x6	# (DW_FORM_data4)
+	.uleb128 0x40	# (DW_AT_frame_base)
+	.uleb128 0x18	# (DW_FORM_exprloc)
+	.uleb128 0x2116	# (DW_AT_GNU_all_tail_call_sites)
+	.uleb128 0x19	# (DW_FORM_flag_present)
+	.byte	0
+	.byte	0
+	.uleb128 0x5	# (abbrev code)
+	.uleb128 0x2e	# (TAG: DW_TAG_subprogram)
+	.byte	0x1	# DW_children_yes
+	.uleb128 0x3f	# (DW_AT_external)
+	.uleb128 0x19	# (DW_FORM_flag_present)
+	.uleb128 0x3	# (DW_AT_name)
+	.uleb128 0xe	# (DW_FORM_strp)
+	.uleb128 0x3a	# (DW_AT_decl_file)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3b	# (DW_AT_decl_line)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x39	# (DW_AT_decl_column)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x27	# (DW_AT_prototyped)
+	.uleb128 0x19	# (DW_FORM_flag_present)
+	.uleb128 0x11	# (DW_AT_low_pc)
+	.uleb128 0x1	# (DW_FORM_addr)
+	.uleb128 0x12	# (DW_AT_high_pc)
+	.uleb128 0x6	# (DW_FORM_data4)
+	.uleb128 0x40	# (DW_AT_frame_base)
+	.uleb128 0x18	# (DW_FORM_exprloc)
+	.uleb128 0x2117	# (DW_AT_GNU_all_call_sites)
+	.uleb128 0x19	# (DW_FORM_flag_present)
+	.uleb128 0x1	# (DW_AT_sibling)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.byte	0
+	.byte	0
+	.uleb128 0x6	# (abbrev code)
+	.uleb128 0x5	# (TAG: DW_TAG_formal_parameter)
+	.byte	0	# DW_children_no
+	.uleb128 0x3	# (DW_AT_name)
+	.uleb128 0xe	# (DW_FORM_strp)
+	.uleb128 0x3a	# (DW_AT_decl_file)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3b	# (DW_AT_decl_line)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x39	# (DW_AT_decl_column)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x49	# (DW_AT_type)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.uleb128 0x2	# (DW_AT_location)
+	.uleb128 0x18	# (DW_FORM_exprloc)
+	.byte	0
+	.byte	0
+	.uleb128 0x7	# (abbrev code)
+	.uleb128 0x1d	# (TAG: DW_TAG_inlined_subroutine)
+	.byte	0x1	# DW_children_yes
+	.uleb128 0x31	# (DW_AT_abstract_origin)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.uleb128 0x11	# (DW_AT_low_pc)
+	.uleb128 0x1	# (DW_FORM_addr)
+	.uleb128 0x12	# (DW_AT_high_pc)
+	.uleb128 0x6	# (DW_FORM_data4)
+	.uleb128 0x58	# (DW_AT_call_file)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x59	# (DW_AT_call_line)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x57	# (DW_AT_call_column)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.byte	0
+	.byte	0
+	.uleb128 0x8	# (abbrev code)
+	.uleb128 0x5	# (TAG: DW_TAG_formal_parameter)
+	.byte	0	# DW_children_no
+	.uleb128 0x31	# (DW_AT_abstract_origin)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.uleb128 0x2	# (DW_AT_location)
+	.uleb128 0x18	# (DW_FORM_exprloc)
+	.byte	0
+	.byte	0
+	.uleb128 0x9	# (abbrev code)
+	.uleb128 0x2e	# (TAG: DW_TAG_subprogram)
+	.byte	0x1	# DW_children_yes
+	.uleb128 0x3f	# (DW_AT_external)
+	.uleb128 0x19	# (DW_FORM_flag_present)
+	.uleb128 0x3	# (DW_AT_name)
+	.uleb128 0xe	# (DW_FORM_strp)
+	.uleb128 0x3a	# (DW_AT_decl_file)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3b	# (DW_AT_decl_line)
+	.uleb128 0x5	# (DW_FORM_data2)
+	.uleb128 0x39	# (DW_AT_decl_column)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x27	# (DW_AT_prototyped)
+	.uleb128 0x19	# (DW_FORM_flag_present)
+	.uleb128 0x20	# (DW_AT_inline)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x34	# (DW_AT_artificial)
+	.uleb128 0x19	# (DW_FORM_flag_present)
+	.byte	0
+	.byte	0
+	.uleb128 0xa	# (abbrev code)
+	.uleb128 0x5	# (TAG: DW_TAG_formal_parameter)
+	.byte	0	# DW_children_no
+	.uleb128 0x3	# (DW_AT_name)
+	.uleb128 0x8	# (DW_FORM_string)
+	.uleb128 0x3a	# (DW_AT_decl_file)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3b	# (DW_AT_decl_line)
+	.uleb128 0x5	# (DW_FORM_data2)
+	.uleb128 0x39	# (DW_AT_decl_column)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x49	# (DW_AT_type)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.byte	0
+	.byte	0
+	.byte	0
+	.section	.debug_aranges,"",@progbits
+	.long	0x1c	# Length of Address Ranges Info
+	.value	0x2	# DWARF aranges version
+	.long	.Ldebug_info0	# Offset of Compilation Unit Info
+	.byte	0x4	# Size of Address
+	.byte	0	# Size of Segment Descriptor
+	.value	0	# Pad to 8 byte boundary
+	.value	0
+	.long	.Ltext0	# Address
+	.long	.Letext0-.Ltext0	# Length
+	.long	0
+	.long	0
+	.section	.debug_line,"",@progbits
+.Ldebug_line0:
+	.section	.debug_str,"MS",@progbits,1
+.LASF2:
+	.string	"long long int"
+.LASF14:
+	.string	"value"
+.LASF19:
+	.string	"_ptwrite32"
+.LASF4:
+	.string	"unsigned int"
+.LASF17:
+	.string	"gdb/gdb/testsuite/gdb.btrace"
+.LASF18:
+	.string	"main"
+.LASF16:
+	.string	"ptwrite.c"
+.LASF8:
+	.string	"long unsigned int"
+.LASF10:
+	.string	"long long unsigned int"
+.LASF13:
+	.string	"ptwrite1"
+.LASF12:
+	.string	"ptwrite2"
+.LASF6:
+	.string	"unsigned char"
+.LASF1:
+	.string	"char"
+.LASF5:
+	.string	"long int"
+.LASF15:
+	.string	"GNU C17 10.3.1 20210422 (Red Hat 10.3.1-1) -m32 -mptwrite -mtune=generic -march=i686 -g"
+.LASF11:
+	.string	"double"
+.LASF7:
+	.string	"short unsigned int"
+.LASF9:
+	.string	"signed char"
+.LASF3:
+	.string	"float"
+.LASF0:
+	.string	"short int"
+	.ident	"GCC: (GNU) 10.3.1 20210422 (Red Hat 10.3.1-1)"
+	.section	.note.GNU-stack,"",@progbits
diff --git a/gdb/testsuite/gdb.btrace/ptwrite.c b/gdb/testsuite/gdb.btrace/ptwrite.c
new file mode 100644
index 00000000000..e10b88573c1
--- /dev/null
+++ b/gdb/testsuite/gdb.btrace/ptwrite.c
@@ -0,0 +1,39 @@ 
+/* This testcase is part of GDB, the GNU debugger.
+
+ Copyright 2024 Free Software Foundation, Inc.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+#include <immintrin.h>
+
+void
+ptwrite1 (int value)
+{
+  _ptwrite32 (value);
+}
+
+void
+ptwrite2 (int value)
+{
+  _ptwrite32 (value);
+}
+
+int
+main (void)
+{
+  ptwrite1 (0x42);
+  ptwrite2 (0x43);
+
+  return 0;
+}
diff --git a/gdb/testsuite/gdb.btrace/ptwrite.exp b/gdb/testsuite/gdb.btrace/ptwrite.exp
new file mode 100644
index 00000000000..43ecfac76cb
--- /dev/null
+++ b/gdb/testsuite/gdb.btrace/ptwrite.exp
@@ -0,0 +1,202 @@ 
+# This testcase is part of GDB, the GNU debugger.
+#
+# Copyright 2024 Free Software Foundation, Inc.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+load_lib gdb-python.exp
+
+require allow_btrace_ptw_tests allow_python_tests
+
+set opts {}
+
+if [info exists COMPILE] {
+    # make check RUNTESTFLAGS="gdb.btrace/ptwrite.exp COMPILE=1"
+    standard_testfile ptwrite.c
+    lappend opts debug additional_flags=-mptwrite
+} elseif {[istarget "i?86-*-*"] || [istarget "x86_64-*-*"]} {
+    if {[is_amd64_regs_target]} {
+	standard_testfile x86_64-ptwrite.S
+    } else {
+	standard_testfile i386-ptwrite.S
+    }
+} else {
+    unsupported "target architecture not supported"
+    return -1
+}
+
+if [prepare_for_testing "failed to prepare" $testfile $srcfile $opts] {
+    return -1
+}
+
+if { ![runto_main] } {
+    untested "failed to run to main"
+    return -1
+}
+
+### 1. Default testrun
+
+# Setup recording
+gdb_test_no_output "set record instruction-history-size unlimited"
+gdb_test_no_output "record btrace pt"
+gdb_test "next" ".*" "next"
+gdb_test "next" ".*" "next 2"
+
+with_test_prefix "Default" {
+    # Test record instruction-history
+    gdb_test "record instruction-history 1" [multi_line \
+	".*\[0-9\]+\t   $hex <ptwrite1\\+\[0-9\]+>:\tptwrite %\[a-z\]+" \
+	"\[0-9\]+\t     \\\[0x42\\\]" \
+	".*\[0-9\]+\t   $hex <ptwrite2\\+\[0-9\]+>:\tptwrite %\[a-z\]+" \
+	"\[0-9\]+\t     \\\[0x43\\\].*" \
+	]
+
+    gdb_test "record instruction-history /a 1" [multi_line \
+	".*\[0-9\]+\t   $hex <ptwrite1\\+\[0-9\]+>:\tptwrite %\[a-z\]+" \
+	".*\[0-9\]+\t   $hex <ptwrite2\\+\[0-9\]+>:\tptwrite %\[a-z\]+.*" \
+	]
+
+    # Test function call history
+    gdb_test "record function-call-history 1,4" [multi_line \
+	"1\tmain" \
+	"2\tptwrite1" \
+	"\t  \\\[0x42\\\]" \
+	"3\tmain" \
+	"4\tptwrite2" \
+	"\t  \\\[0x43\\\]" \
+	]
+
+    gdb_test "record function-call-history /a 1,4" [multi_line \
+	"1\tmain" \
+	"2\tptwrite1" \
+	"3\tmain" \
+	"4\tptwrite2" \
+	]
+}
+
+# Test payload printing during stepping
+with_test_prefix "Stepping" {
+    gdb_test "record goto 10" "Can't go to an auxiliary instruction\."
+    gdb_test "record goto 9" ".*ptwrite.* at .*"
+    gdb_test "stepi" ".*\\\[0x42\\\].*"
+    gdb_test "reverse-stepi" ".*\\\[0x42\\\].*"
+    gdb_test "continue" [multi_line \
+	    ".*\\\[0x42\\\]" \
+	    "\\\[0x43\\\].*" \
+	    ]
+    gdb_test "reverse-continue" [multi_line \
+	    ".*\\\[0x43\\\]" \
+	    "\\\[0x42\\\].*" \
+	    ]
+}
+
+# Test auxiliary type in python
+gdb_test_multiline "auxiliary type in python" \
+    "python" "" \
+    "h = gdb.current_recording().instruction_history" "" \
+    "for insn in h:" "" \
+    "    if hasattr(insn, 'decoded'):" "" \
+    "        print(insn.decoded.decode())" "" \
+    "    elif hasattr(insn, 'data'):" "" \
+    "        print(insn.data)" "" \
+    "end" \
+    [multi_line \
+	".*mov    -0x4\\\(%(e|r)bp\\\),%(e|r)ax" \
+	"ptwrite %eax" \
+	"0x42" \
+	"nop.*" \
+	"mov    -0x4\\\(%(e|r)bp\\\),%(e|r)ax" \
+	"ptwrite %eax" \
+	"0x43" \
+	"nop.*"
+    ]
+
+
+### 2. Test filter registration
+### 2.1 Custom filter
+with_test_prefix "Custom" {
+    gdb_test_multiline "register filter in python" \
+	"python" "" \
+	"def my_filter(payload, ip):" "" \
+	"    if  payload == 66:" "" \
+	"        return \"payload: {0}, ip: {1:#x}\".format(payload, ip)" "" \
+	"    else:" "" \
+	"        return None" "" \
+	"def factory(thread): return my_filter" "" \
+	"import gdb.ptwrite" "" \
+	"gdb.ptwrite.register_filter_factory(factory)" "" \
+	"end" ""
+
+    gdb_test "record instruction-history 1" [multi_line \
+	".*\[0-9\]+\t   $hex <ptwrite1\\+\[0-9\]+>:\tptwrite %\[a-z\]+" \
+	"\[0-9\]+\t     \\\[payload: 66, ip: $hex\\\]" \
+	".*\[0-9\]+\t   $hex <ptwrite2\\+\[0-9\]+>:\tptwrite %\[a-z\]+" \
+	"\[0-9\]+\t   $hex <ptwrite2\\+\[0-9\]+>:.*" \
+	]
+}
+
+### 2.2 None as filter. This resets the default behaviour.
+with_test_prefix "None" {
+    gdb_test_multiline "register filter in python" \
+	"python" "" \
+	"import gdb.ptwrite" "" \
+	"gdb.ptwrite.register_filter_factory(None)" "" \
+	"end" ""
+
+    gdb_test "record instruction-history 1" [multi_line \
+	".*\[0-9\]+\t   $hex <ptwrite1\\+\[0-9\]+>:\tptwrite %\[a-z\]+" \
+	"\[0-9\]+\t     \\\[0x42\\\]" \
+	".*\[0-9\]+\t   $hex <ptwrite2\\+\[0-9\]+>:\tptwrite %\[a-z\]+" \
+	"\[0-9\]+\t     \\\[0x43\\\].*" \
+	]
+}
+
+### 2.3 Lambdas as filter
+with_test_prefix "Lambdas" {
+    gdb_test_multiline "register filter in python" \
+	"python" "" \
+	"import gdb.ptwrite" "" \
+	"lambda_filter = lambda payload, ip: \"{}\".format(payload + 2)" "" \
+	"gdb.ptwrite.register_filter_factory(lambda thread : lambda_filter)" "" \
+	"end" ""
+
+    gdb_test "record instruction-history 1" [multi_line \
+	".*\[0-9\]+\t   $hex <ptwrite1\\+\[0-9\]+>:\tptwrite %\[a-z\]+" \
+	"\[0-9\]+\t     \\\[68\\\]" \
+	".*\[0-9\]+\t   $hex <ptwrite2\\+\[0-9\]+>:\tptwrite %\[a-z\]+" \
+	"\[0-9\]+\t     \\\[69\\\].*" \
+	] "Lambdas: record instruction-history 1"
+}
+
+### 2.4 Functors as filter
+with_test_prefix "Functors" {
+    gdb_test_multiline "register filter in python" \
+	"python" "" \
+	"import gdb.ptwrite" "" \
+	"class foobar(object):" "" \
+	"    def __init__(self):" "" \
+	"        self.variable = 0" "" \
+	"    def __call__(self, payload, ip):" "" \
+	"        self.variable += 1" "" \
+	"        return \"{}, {}\".format(self.variable, payload)" "" \
+	"gdb.ptwrite.register_filter_factory(lambda thread : foobar())" "" \
+	"end" ""
+
+    gdb_test "record instruction-history 1" [multi_line \
+	".*\[0-9\]+\t   $hex <ptwrite1\\+\[0-9\]+>:\tptwrite %\[a-z\]+" \
+	"\[0-9\]+\t     \\\[1, 66\\\]" \
+	".*\[0-9\]+\t   $hex <ptwrite2\\+\[0-9\]+>:\tptwrite %\[a-z\]+" \
+	"\[0-9\]+\t     \\\[2, 67\\\].*" \
+	] "Functors: record instruction-history 1"
+}
diff --git a/gdb/testsuite/gdb.btrace/x86_64-ptwrite.S b/gdb/testsuite/gdb.btrace/x86_64-ptwrite.S
new file mode 100644
index 00000000000..be4d204dc61
--- /dev/null
+++ b/gdb/testsuite/gdb.btrace/x86_64-ptwrite.S
@@ -0,0 +1,544 @@ 
+/* This testcase is part of GDB, the GNU debugger.
+
+   Copyright 2024 Free Software Foundation, Inc.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+
+   This file has been generated using gcc version 10.3.1 20210422
+   (Red Hat 10.3.1-1):
+   gcc -S -dA -g -mptwrite ptwrite.c -o x86_64-ptwrite.S.  */
+
+	.file	"ptwrite.c"
+	.text
+.Ltext0:
+	.globl	ptwrite1
+	.type	ptwrite1, @function
+ptwrite1:
+.LFB4096:
+	.file 1 "ptwrite.c"
+	# ptwrite.c:22:1
+	.loc 1 22 1
+	.cfi_startproc
+# BLOCK 2 seq:0
+# PRED: ENTRY (FALLTHRU)
+	pushq	%rbp
+	.cfi_def_cfa_offset 16
+	.cfi_offset 6, -16
+	movq	%rsp, %rbp
+	.cfi_def_cfa_register 6
+	movl	%edi, -20(%rbp)
+	# ptwrite.c:23:3
+	.loc 1 23 3
+	movl	-20(%rbp), %eax
+	movl	%eax, -4(%rbp)
+.LBB6:
+.LBB7:
+	.file 2 "/usr/lib/gcc/x86_64-redhat-linux/10/include/immintrin.h"
+	# /usr/lib/gcc/x86_64-redhat-linux/10/include/immintrin.h:307:3
+	.loc 2 307 3
+	movl	-4(%rbp), %eax
+	ptwrite	%eax
+	# /usr/lib/gcc/x86_64-redhat-linux/10/include/immintrin.h:308:1
+	.loc 2 308 1
+	nop
+.LBE7:
+.LBE6:
+	# ptwrite.c:24:1
+	.loc 1 24 1
+	nop
+	popq	%rbp
+	.cfi_def_cfa 7, 8
+# SUCC: EXIT [always]
+	ret
+	.cfi_endproc
+.LFE4096:
+	.size	ptwrite1, .-ptwrite1
+	.globl	ptwrite2
+	.type	ptwrite2, @function
+ptwrite2:
+.LFB4097:
+	# ptwrite.c:28:1
+	.loc 1 28 1
+	.cfi_startproc
+# BLOCK 2 seq:0
+# PRED: ENTRY (FALLTHRU)
+	pushq	%rbp
+	.cfi_def_cfa_offset 16
+	.cfi_offset 6, -16
+	movq	%rsp, %rbp
+	.cfi_def_cfa_register 6
+	movl	%edi, -20(%rbp)
+	# ptwrite.c:29:3
+	.loc 1 29 3
+	movl	-20(%rbp), %eax
+	movl	%eax, -4(%rbp)
+.LBB8:
+.LBB9:
+	# /usr/lib/gcc/x86_64-redhat-linux/10/include/immintrin.h:307:3
+	.loc 2 307 3
+	movl	-4(%rbp), %eax
+	ptwrite	%eax
+	# /usr/lib/gcc/x86_64-redhat-linux/10/include/immintrin.h:308:1
+	.loc 2 308 1
+	nop
+.LBE9:
+.LBE8:
+	# ptwrite.c:30:1
+	.loc 1 30 1
+	nop
+	popq	%rbp
+	.cfi_def_cfa 7, 8
+# SUCC: EXIT [always]
+	ret
+	.cfi_endproc
+.LFE4097:
+	.size	ptwrite2, .-ptwrite2
+	.globl	main
+	.type	main, @function
+main:
+.LFB4098:
+	# ptwrite.c:34:1
+	.loc 1 34 1
+	.cfi_startproc
+# BLOCK 2 seq:0
+# PRED: ENTRY (FALLTHRU)
+	pushq	%rbp
+	.cfi_def_cfa_offset 16
+	.cfi_offset 6, -16
+	movq	%rsp, %rbp
+	.cfi_def_cfa_register 6
+	# ptwrite.c:35:3
+	.loc 1 35 3
+	movl	$66, %edi
+	call	ptwrite1
+	# ptwrite.c:36:3
+	.loc 1 36 3
+	movl	$67, %edi
+	call	ptwrite2
+	# ptwrite.c:38:10
+	.loc 1 38 10
+	movl	$0, %eax
+	# ptwrite.c:39:1
+	.loc 1 39 1
+	popq	%rbp
+	.cfi_def_cfa 7, 8
+# SUCC: EXIT [always]
+	ret
+	.cfi_endproc
+.LFE4098:
+	.size	main, .-main
+.Letext0:
+	.section	.debug_info,"",@progbits
+.Ldebug_info0:
+	.long	0x159	# Length of Compilation Unit Info
+	.value	0x4	# DWARF version number
+	.long	.Ldebug_abbrev0	# Offset Into Abbrev. Section
+	.byte	0x8	# Pointer Size (in bytes)
+	.uleb128 0x1	# (DIE (0xb) DW_TAG_compile_unit)
+	.long	.LASF15	# DW_AT_producer: "GNU C17 10.3.1 20210422 (Red Hat 10.3.1-1) -mptwrite -mtune=generic -march=x86-64 -g"
+	.byte	0xc	# DW_AT_language
+	.long	.LASF16	# DW_AT_name: "ptwrite.c"
+	.long	.LASF17	# DW_AT_comp_dir: "gdb/gdb/testsuite/gdb.btrace"
+	.quad	.Ltext0	# DW_AT_low_pc
+	.quad	.Letext0-.Ltext0	# DW_AT_high_pc
+	.long	.Ldebug_line0	# DW_AT_stmt_list
+	.uleb128 0x2	# (DIE (0x2d) DW_TAG_base_type)
+	.byte	0x4	# DW_AT_byte_size
+	.byte	0x5	# DW_AT_encoding
+	.ascii "int\0"	# DW_AT_name
+	.uleb128 0x3	# (DIE (0x34) DW_TAG_base_type)
+	.byte	0x2	# DW_AT_byte_size
+	.byte	0x5	# DW_AT_encoding
+	.long	.LASF0	# DW_AT_name: "short int"
+	.uleb128 0x3	# (DIE (0x3b) DW_TAG_base_type)
+	.byte	0x1	# DW_AT_byte_size
+	.byte	0x6	# DW_AT_encoding
+	.long	.LASF1	# DW_AT_name: "char"
+	.uleb128 0x3	# (DIE (0x42) DW_TAG_base_type)
+	.byte	0x8	# DW_AT_byte_size
+	.byte	0x5	# DW_AT_encoding
+	.long	.LASF2	# DW_AT_name: "long long int"
+	.uleb128 0x3	# (DIE (0x49) DW_TAG_base_type)
+	.byte	0x4	# DW_AT_byte_size
+	.byte	0x4	# DW_AT_encoding
+	.long	.LASF3	# DW_AT_name: "float"
+	.uleb128 0x3	# (DIE (0x50) DW_TAG_base_type)
+	.byte	0x8	# DW_AT_byte_size
+	.byte	0x7	# DW_AT_encoding
+	.long	.LASF4	# DW_AT_name: "long unsigned int"
+	.uleb128 0x3	# (DIE (0x57) DW_TAG_base_type)
+	.byte	0x8	# DW_AT_byte_size
+	.byte	0x5	# DW_AT_encoding
+	.long	.LASF5	# DW_AT_name: "long int"
+	.uleb128 0x3	# (DIE (0x5e) DW_TAG_base_type)
+	.byte	0x1	# DW_AT_byte_size
+	.byte	0x8	# DW_AT_encoding
+	.long	.LASF6	# DW_AT_name: "unsigned char"
+	.uleb128 0x3	# (DIE (0x65) DW_TAG_base_type)
+	.byte	0x2	# DW_AT_byte_size
+	.byte	0x7	# DW_AT_encoding
+	.long	.LASF7	# DW_AT_name: "short unsigned int"
+	.uleb128 0x3	# (DIE (0x6c) DW_TAG_base_type)
+	.byte	0x4	# DW_AT_byte_size
+	.byte	0x7	# DW_AT_encoding
+	.long	.LASF8	# DW_AT_name: "unsigned int"
+	.uleb128 0x3	# (DIE (0x73) DW_TAG_base_type)
+	.byte	0x1	# DW_AT_byte_size
+	.byte	0x6	# DW_AT_encoding
+	.long	.LASF9	# DW_AT_name: "signed char"
+	.uleb128 0x3	# (DIE (0x7a) DW_TAG_base_type)
+	.byte	0x8	# DW_AT_byte_size
+	.byte	0x7	# DW_AT_encoding
+	.long	.LASF10	# DW_AT_name: "long long unsigned int"
+	.uleb128 0x3	# (DIE (0x81) DW_TAG_base_type)
+	.byte	0x8	# DW_AT_byte_size
+	.byte	0x4	# DW_AT_encoding
+	.long	.LASF11	# DW_AT_name: "double"
+	.uleb128 0x4	# (DIE (0x88) DW_TAG_subprogram)
+			# DW_AT_external
+	.long	.LASF18	# DW_AT_name: "main"
+	.byte	0x1	# DW_AT_decl_file (ptwrite.c)
+	.byte	0x21	# DW_AT_decl_line
+	.byte	0x1	# DW_AT_decl_column
+			# DW_AT_prototyped
+	.long	0x2d	# DW_AT_type
+	.quad	.LFB4098	# DW_AT_low_pc
+	.quad	.LFE4098-.LFB4098	# DW_AT_high_pc
+	.uleb128 0x1	# DW_AT_frame_base
+	.byte	0x9c	# DW_OP_call_frame_cfa
+			# DW_AT_GNU_all_tail_call_sites
+	.uleb128 0x5	# (DIE (0xa6) DW_TAG_subprogram)
+			# DW_AT_external
+	.long	.LASF12	# DW_AT_name: "ptwrite2"
+	.byte	0x1	# DW_AT_decl_file (ptwrite.c)
+	.byte	0x1b	# DW_AT_decl_line
+	.byte	0x1	# DW_AT_decl_column
+			# DW_AT_prototyped
+	.quad	.LFB4097	# DW_AT_low_pc
+	.quad	.LFE4097-.LFB4097	# DW_AT_high_pc
+	.uleb128 0x1	# DW_AT_frame_base
+	.byte	0x9c	# DW_OP_call_frame_cfa
+			# DW_AT_GNU_all_call_sites
+	.long	0xf5	# DW_AT_sibling
+	.uleb128 0x6	# (DIE (0xc4) DW_TAG_formal_parameter)
+	.long	.LASF14	# DW_AT_name: "value"
+	.byte	0x1	# DW_AT_decl_file (ptwrite.c)
+	.byte	0x1b	# DW_AT_decl_line
+	.byte	0xf	# DW_AT_decl_column
+	.long	0x2d	# DW_AT_type
+	.uleb128 0x2	# DW_AT_location
+	.byte	0x91	# DW_OP_fbreg
+	.sleb128 -36
+	.uleb128 0x7	# (DIE (0xd3) DW_TAG_inlined_subroutine)
+	.long	0x144	# DW_AT_abstract_origin
+	.quad	.LBB8	# DW_AT_low_pc
+	.quad	.LBE8-.LBB8	# DW_AT_high_pc
+	.byte	0x1	# DW_AT_call_file (ptwrite.c)
+	.byte	0x1d	# DW_AT_call_line
+	.byte	0x3	# DW_AT_call_column
+	.uleb128 0x8	# (DIE (0xeb) DW_TAG_formal_parameter)
+	.long	0x14e	# DW_AT_abstract_origin
+	.uleb128 0x2	# DW_AT_location
+	.byte	0x91	# DW_OP_fbreg
+	.sleb128 -20
+	.byte	0	# end of children of DIE 0xd3
+	.byte	0	# end of children of DIE 0xa6
+	.uleb128 0x5	# (DIE (0xf5) DW_TAG_subprogram)
+			# DW_AT_external
+	.long	.LASF13	# DW_AT_name: "ptwrite1"
+	.byte	0x1	# DW_AT_decl_file (ptwrite.c)
+	.byte	0x15	# DW_AT_decl_line
+	.byte	0x1	# DW_AT_decl_column
+			# DW_AT_prototyped
+	.quad	.LFB4096	# DW_AT_low_pc
+	.quad	.LFE4096-.LFB4096	# DW_AT_high_pc
+	.uleb128 0x1	# DW_AT_frame_base
+	.byte	0x9c	# DW_OP_call_frame_cfa
+			# DW_AT_GNU_all_call_sites
+	.long	0x144	# DW_AT_sibling
+	.uleb128 0x6	# (DIE (0x113) DW_TAG_formal_parameter)
+	.long	.LASF14	# DW_AT_name: "value"
+	.byte	0x1	# DW_AT_decl_file (ptwrite.c)
+	.byte	0x15	# DW_AT_decl_line
+	.byte	0xf	# DW_AT_decl_column
+	.long	0x2d	# DW_AT_type
+	.uleb128 0x2	# DW_AT_location
+	.byte	0x91	# DW_OP_fbreg
+	.sleb128 -36
+	.uleb128 0x7	# (DIE (0x122) DW_TAG_inlined_subroutine)
+	.long	0x144	# DW_AT_abstract_origin
+	.quad	.LBB6	# DW_AT_low_pc
+	.quad	.LBE6-.LBB6	# DW_AT_high_pc
+	.byte	0x1	# DW_AT_call_file (ptwrite.c)
+	.byte	0x17	# DW_AT_call_line
+	.byte	0x3	# DW_AT_call_column
+	.uleb128 0x8	# (DIE (0x13a) DW_TAG_formal_parameter)
+	.long	0x14e	# DW_AT_abstract_origin
+	.uleb128 0x2	# DW_AT_location
+	.byte	0x91	# DW_OP_fbreg
+	.sleb128 -20
+	.byte	0	# end of children of DIE 0x122
+	.byte	0	# end of children of DIE 0xf5
+	.uleb128 0x9	# (DIE (0x144) DW_TAG_subprogram)
+			# DW_AT_external
+	.long	.LASF19	# DW_AT_name: "_ptwrite32"
+	.byte	0x2	# DW_AT_decl_file (/usr/lib/gcc/x86_64-redhat-linux/10/include/immintrin.h)
+	.value	0x131	# DW_AT_decl_line
+	.byte	0x1	# DW_AT_decl_column
+			# DW_AT_prototyped
+	.byte	0x3	# DW_AT_inline
+			# DW_AT_artificial
+	.uleb128 0xa	# (DIE (0x14e) DW_TAG_formal_parameter)
+	.ascii "__B\0"	# DW_AT_name
+	.byte	0x2	# DW_AT_decl_file (/usr/lib/gcc/x86_64-redhat-linux/10/include/immintrin.h)
+	.value	0x131	# DW_AT_decl_line
+	.byte	0x16	# DW_AT_decl_column
+	.long	0x6c	# DW_AT_type
+	.byte	0	# end of children of DIE 0x144
+	.byte	0	# end of children of DIE 0xb
+	.section	.debug_abbrev,"",@progbits
+.Ldebug_abbrev0:
+	.uleb128 0x1	# (abbrev code)
+	.uleb128 0x11	# (TAG: DW_TAG_compile_unit)
+	.byte	0x1	# DW_children_yes
+	.uleb128 0x25	# (DW_AT_producer)
+	.uleb128 0xe	# (DW_FORM_strp)
+	.uleb128 0x13	# (DW_AT_language)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3	# (DW_AT_name)
+	.uleb128 0xe	# (DW_FORM_strp)
+	.uleb128 0x1b	# (DW_AT_comp_dir)
+	.uleb128 0xe	# (DW_FORM_strp)
+	.uleb128 0x11	# (DW_AT_low_pc)
+	.uleb128 0x1	# (DW_FORM_addr)
+	.uleb128 0x12	# (DW_AT_high_pc)
+	.uleb128 0x7	# (DW_FORM_data8)
+	.uleb128 0x10	# (DW_AT_stmt_list)
+	.uleb128 0x17	# (DW_FORM_sec_offset)
+	.byte	0
+	.byte	0
+	.uleb128 0x2	# (abbrev code)
+	.uleb128 0x24	# (TAG: DW_TAG_base_type)
+	.byte	0	# DW_children_no
+	.uleb128 0xb	# (DW_AT_byte_size)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3e	# (DW_AT_encoding)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3	# (DW_AT_name)
+	.uleb128 0x8	# (DW_FORM_string)
+	.byte	0
+	.byte	0
+	.uleb128 0x3	# (abbrev code)
+	.uleb128 0x24	# (TAG: DW_TAG_base_type)
+	.byte	0	# DW_children_no
+	.uleb128 0xb	# (DW_AT_byte_size)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3e	# (DW_AT_encoding)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3	# (DW_AT_name)
+	.uleb128 0xe	# (DW_FORM_strp)
+	.byte	0
+	.byte	0
+	.uleb128 0x4	# (abbrev code)
+	.uleb128 0x2e	# (TAG: DW_TAG_subprogram)
+	.byte	0	# DW_children_no
+	.uleb128 0x3f	# (DW_AT_external)
+	.uleb128 0x19	# (DW_FORM_flag_present)
+	.uleb128 0x3	# (DW_AT_name)
+	.uleb128 0xe	# (DW_FORM_strp)
+	.uleb128 0x3a	# (DW_AT_decl_file)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3b	# (DW_AT_decl_line)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x39	# (DW_AT_decl_column)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x27	# (DW_AT_prototyped)
+	.uleb128 0x19	# (DW_FORM_flag_present)
+	.uleb128 0x49	# (DW_AT_type)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.uleb128 0x11	# (DW_AT_low_pc)
+	.uleb128 0x1	# (DW_FORM_addr)
+	.uleb128 0x12	# (DW_AT_high_pc)
+	.uleb128 0x7	# (DW_FORM_data8)
+	.uleb128 0x40	# (DW_AT_frame_base)
+	.uleb128 0x18	# (DW_FORM_exprloc)
+	.uleb128 0x2116	# (DW_AT_GNU_all_tail_call_sites)
+	.uleb128 0x19	# (DW_FORM_flag_present)
+	.byte	0
+	.byte	0
+	.uleb128 0x5	# (abbrev code)
+	.uleb128 0x2e	# (TAG: DW_TAG_subprogram)
+	.byte	0x1	# DW_children_yes
+	.uleb128 0x3f	# (DW_AT_external)
+	.uleb128 0x19	# (DW_FORM_flag_present)
+	.uleb128 0x3	# (DW_AT_name)
+	.uleb128 0xe	# (DW_FORM_strp)
+	.uleb128 0x3a	# (DW_AT_decl_file)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3b	# (DW_AT_decl_line)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x39	# (DW_AT_decl_column)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x27	# (DW_AT_prototyped)
+	.uleb128 0x19	# (DW_FORM_flag_present)
+	.uleb128 0x11	# (DW_AT_low_pc)
+	.uleb128 0x1	# (DW_FORM_addr)
+	.uleb128 0x12	# (DW_AT_high_pc)
+	.uleb128 0x7	# (DW_FORM_data8)
+	.uleb128 0x40	# (DW_AT_frame_base)
+	.uleb128 0x18	# (DW_FORM_exprloc)
+	.uleb128 0x2117	# (DW_AT_GNU_all_call_sites)
+	.uleb128 0x19	# (DW_FORM_flag_present)
+	.uleb128 0x1	# (DW_AT_sibling)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.byte	0
+	.byte	0
+	.uleb128 0x6	# (abbrev code)
+	.uleb128 0x5	# (TAG: DW_TAG_formal_parameter)
+	.byte	0	# DW_children_no
+	.uleb128 0x3	# (DW_AT_name)
+	.uleb128 0xe	# (DW_FORM_strp)
+	.uleb128 0x3a	# (DW_AT_decl_file)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3b	# (DW_AT_decl_line)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x39	# (DW_AT_decl_column)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x49	# (DW_AT_type)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.uleb128 0x2	# (DW_AT_location)
+	.uleb128 0x18	# (DW_FORM_exprloc)
+	.byte	0
+	.byte	0
+	.uleb128 0x7	# (abbrev code)
+	.uleb128 0x1d	# (TAG: DW_TAG_inlined_subroutine)
+	.byte	0x1	# DW_children_yes
+	.uleb128 0x31	# (DW_AT_abstract_origin)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.uleb128 0x11	# (DW_AT_low_pc)
+	.uleb128 0x1	# (DW_FORM_addr)
+	.uleb128 0x12	# (DW_AT_high_pc)
+	.uleb128 0x7	# (DW_FORM_data8)
+	.uleb128 0x58	# (DW_AT_call_file)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x59	# (DW_AT_call_line)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x57	# (DW_AT_call_column)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.byte	0
+	.byte	0
+	.uleb128 0x8	# (abbrev code)
+	.uleb128 0x5	# (TAG: DW_TAG_formal_parameter)
+	.byte	0	# DW_children_no
+	.uleb128 0x31	# (DW_AT_abstract_origin)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.uleb128 0x2	# (DW_AT_location)
+	.uleb128 0x18	# (DW_FORM_exprloc)
+	.byte	0
+	.byte	0
+	.uleb128 0x9	# (abbrev code)
+	.uleb128 0x2e	# (TAG: DW_TAG_subprogram)
+	.byte	0x1	# DW_children_yes
+	.uleb128 0x3f	# (DW_AT_external)
+	.uleb128 0x19	# (DW_FORM_flag_present)
+	.uleb128 0x3	# (DW_AT_name)
+	.uleb128 0xe	# (DW_FORM_strp)
+	.uleb128 0x3a	# (DW_AT_decl_file)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3b	# (DW_AT_decl_line)
+	.uleb128 0x5	# (DW_FORM_data2)
+	.uleb128 0x39	# (DW_AT_decl_column)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x27	# (DW_AT_prototyped)
+	.uleb128 0x19	# (DW_FORM_flag_present)
+	.uleb128 0x20	# (DW_AT_inline)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x34	# (DW_AT_artificial)
+	.uleb128 0x19	# (DW_FORM_flag_present)
+	.byte	0
+	.byte	0
+	.uleb128 0xa	# (abbrev code)
+	.uleb128 0x5	# (TAG: DW_TAG_formal_parameter)
+	.byte	0	# DW_children_no
+	.uleb128 0x3	# (DW_AT_name)
+	.uleb128 0x8	# (DW_FORM_string)
+	.uleb128 0x3a	# (DW_AT_decl_file)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x3b	# (DW_AT_decl_line)
+	.uleb128 0x5	# (DW_FORM_data2)
+	.uleb128 0x39	# (DW_AT_decl_column)
+	.uleb128 0xb	# (DW_FORM_data1)
+	.uleb128 0x49	# (DW_AT_type)
+	.uleb128 0x13	# (DW_FORM_ref4)
+	.byte	0
+	.byte	0
+	.byte	0
+	.section	.debug_aranges,"",@progbits
+	.long	0x2c	# Length of Address Ranges Info
+	.value	0x2	# DWARF aranges version
+	.long	.Ldebug_info0	# Offset of Compilation Unit Info
+	.byte	0x8	# Size of Address
+	.byte	0	# Size of Segment Descriptor
+	.value	0	# Pad to 16 byte boundary
+	.value	0
+	.quad	.Ltext0	# Address
+	.quad	.Letext0-.Ltext0	# Length
+	.quad	0
+	.quad	0
+	.section	.debug_line,"",@progbits
+.Ldebug_line0:
+	.section	.debug_str,"MS",@progbits,1
+.LASF2:
+	.string	"long long int"
+.LASF14:
+	.string	"value"
+.LASF19:
+	.string	"_ptwrite32"
+.LASF8:
+	.string	"unsigned int"
+.LASF17:
+	.string	"gdb/gdb/testsuite/gdb.btrace"
+.LASF18:
+	.string	"main"
+.LASF16:
+	.string	"ptwrite.c"
+.LASF4:
+	.string	"long unsigned int"
+.LASF10:
+	.string	"long long unsigned int"
+.LASF15:
+	.string	"GNU C17 10.3.1 20210422 (Red Hat 10.3.1-1) -mptwrite -mtune=generic -march=x86-64 -g"
+.LASF13:
+	.string	"ptwrite1"
+.LASF12:
+	.string	"ptwrite2"
+.LASF6:
+	.string	"unsigned char"
+.LASF1:
+	.string	"char"
+.LASF5:
+	.string	"long int"
+.LASF11:
+	.string	"double"
+.LASF7:
+	.string	"short unsigned int"
+.LASF9:
+	.string	"signed char"
+.LASF3:
+	.string	"float"
+.LASF0:
+	.string	"short int"
+	.ident	"GCC: (GNU) 10.3.1 20210422 (Red Hat 10.3.1-1)"
+	.section	.note.GNU-stack,"",@progbits
diff --git a/gdb/testsuite/lib/gdb.exp b/gdb/testsuite/lib/gdb.exp
index dfe19c9410d..6e9ec8bee49 100644
--- a/gdb/testsuite/lib/gdb.exp
+++ b/gdb/testsuite/lib/gdb.exp
@@ -4258,6 +4258,78 @@  gdb_caching_proc allow_btrace_pt_tests {} {
     return $allow_btrace_pt_tests
 }
 
+# Run a test on the target to see if it supports ptwrite instructions and
+# if GDB can decode ptwrite events.  Return 1 if so, 0 if it does not.
+
+gdb_caching_proc allow_btrace_ptw_tests {} {
+    global srcdir subdir gdb_prompt inferior_exited_re decimal
+
+    require allow_btrace_pt_tests
+    set me "allow_btrace_ptw_tests"
+
+    set src {
+	int
+	main ()
+	{
+	  asm volatile ("PTWRITE %0;" : : "b"(0x42));
+	  return 0;
+	}
+    }
+
+    if {![gdb_simple_compile $me $src executable]} {
+	return 1
+    }
+
+    gdb_exit
+    gdb_start
+    gdb_reinitialize_dir $srcdir/$subdir
+    gdb_load "$obj"
+    if ![runto_main] {
+	return 1
+    }
+
+    gdb_test_no_output "record btrace pt" "$me: record btrace pt"
+
+    set allow_btrace_ptw_tests 2
+    gdb_test_multiple "next" "$me: next" {
+	-re -wrap ".*Illegal instruction.*" {
+	    verbose -log "$me:  ptwrite instruction support not detected."
+	    set allow_btrace_ptw_tests 0
+	}
+	-re -wrap ".*$inferior_exited_re normally.*" {
+	    verbose -log "$me:  ptwrite support not detected."
+	    set allow_btrace_ptw_tests 0
+	}
+	-re -wrap "$decimal.*(at|in|return 0).*" {
+	    set allow_btrace_ptw_tests 1
+	}
+    }
+
+    if { $allow_btrace_ptw_tests == 1 } {
+	# Show the func-call-history to get the packet trace.
+	gdb_test "record function-call-history" ".*"
+
+	gdb_test_multiple "maintenance btrace packet-history 0,1000" \
+	    "$me: check decoding support" {
+	    -re  "ptw" {
+		verbose -log "$me:  ptwrite decoding support detected."
+		set allow_btrace_ptw_tests 1
+	    }
+	    -re ".*${gdb_prompt} $" {
+		verbose -log "$me:  ptwrite decoding support not detected."
+		set allow_btrace_ptw_tests 0
+	    }
+	}
+    }
+
+    gdb_exit
+    remote_file build delete $obj
+
+    verbose "$me:  returning $allow_btrace_ptw_tests" 2
+    return $allow_btrace_ptw_tests
+}
+
+
 # Run a test on the target to see if it supports Aarch64 SVE hardware.
 # Return 1 if so, 0 if it does not.  Note this causes a restart of GDB.
 
diff --git a/gdbsupport/common.m4 b/gdbsupport/common.m4
index 6c317ff2450..d89c3aed0fe 100644
--- a/gdbsupport/common.m4
+++ b/gdbsupport/common.m4
@@ -200,6 +200,8 @@  AC_DEFUN([GDB_AC_COMMON], [
       AC_CHECK_FUNCS(pt_insn_event)
       AC_CHECK_MEMBERS([struct pt_insn.enabled, struct pt_insn.resynced], [], [],
 		       [#include <intel-pt.h>])
+      AC_CHECK_MEMBERS([struct pt_event.variant.ptwrite], [], [],
+		       [#include <intel-pt.h>])
       LIBS=$save_LIBS
     fi
   fi
diff --git a/gdbsupport/config.in b/gdbsupport/config.in
index 832c92b2cb1..8467072752a 100644
--- a/gdbsupport/config.in
+++ b/gdbsupport/config.in
@@ -256,6 +256,9 @@ 
 /* Define to 1 if you have the <string.h> header file. */
 #undef HAVE_STRING_H
 
+/* Define to 1 if `variant.ptwrite' is a member of `struct pt_event'. */
+#undef HAVE_STRUCT_PT_EVENT_VARIANT_PTWRITE
+
 /* Define to 1 if `enabled' is a member of `struct pt_insn'. */
 #undef HAVE_STRUCT_PT_INSN_ENABLED
 
diff --git a/gdbsupport/configure b/gdbsupport/configure
index 19b19c42c6f..71966e92f1c 100755
--- a/gdbsupport/configure
+++ b/gdbsupport/configure
@@ -12991,6 +12991,17 @@  cat >>confdefs.h <<_ACEOF
 _ACEOF
 
 
+fi
+
+      ac_fn_c_check_member "$LINENO" "struct pt_event" "variant.ptwrite" "ac_cv_member_struct_pt_event_variant_ptwrite" "#include <intel-pt.h>
+"
+if test "x$ac_cv_member_struct_pt_event_variant_ptwrite" = xyes; then :
+
+cat >>confdefs.h <<_ACEOF
+#define HAVE_STRUCT_PT_EVENT_VARIANT_PTWRITE 1
+_ACEOF
+
+
 fi
 
       LIBS=$save_LIBS