RE: [PATCH 1/1] gdb, gdbserver: Add Intel APX register support

["Joos, Christina" <christina.joos@intel.com>]

> -----Original Message-----
> From: Hannes Domani <ssbssa@yahoo.de>
> Sent: Freitag, 4. September 2026 21:43
> To: gdb-patches@sourceware.org; Joos, Christina <christina.joos@intel.com>
> Subject: Re: [PATCH 1/1] gdb, gdbserver: Add Intel APX register support
> 
>  Am Samstag, 25. Juli 2026 um 12:55:55 MESZ hat Christina Joos
> <christina.joos@intel.com> Folgendes geschrieben:
> 
> > From: "H.J. Lu" <hjl.tools@gmail.com>
> >
> > Intel Advanced Performance Extensions (APX) doubles the number of
> > general-purpose registers (GPRs) from 16 to 32 (r16-r31).
> >
> > Those new 64-bit Extended GPRs (EGPRs) do not change the size of the
> > XSAVE area, as they take up the space left behind by the deprecated
> > MPX registers.
> >
> > In contrast to the legacy GPRS, EGPRs are not enabled by default in
> > 64-bit mode but are xcr0 enabled based on APX_F Intel APX state.
> > Define X86_XSTATE_APX_F to support this new configuration.
> >
> > Add gdb and gdbserver registers support for those new 64-bit EGPRs.
> > Also add byte, word and dword pseudo register support.
> >
> > Co-Authored-By:  Christina Joos <christina.joos@intel.com>
> >
> > diff --git a/gdb/testsuite/gdb.arch/amd64-apx.c
> > b/gdb/testsuite/gdb.arch/amd64-apx.c
> > new file mode 100644
> > index 00000000000..c9539d16cf1
> > --- /dev/null
> > +++ b/gdb/testsuite/gdb.arch/amd64-apx.c
> > @@ -0,0 +1,66 @@
> > +/* Copyright 2024-2026 Free Software Foundation, Inc.
> > +
> > +  This file is part of GDB.
> > +
> > +  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/>.
> > +
> > +  Test program for Intel APX Extended GPRs (EGPRs).  */
> > +
> > +long data[] = {
> > +  0x0000000004030201,
> > +  0x0000000014131211,
> > +  0x0000000024232221,
> > +  0x0000000034333231,
> > +  0x0000000044434241,
> > +  0x0000000054535251,
> > +  0x0000000064636261,
> > +  0x0000000074737271,
> > +  0x0000000084838281,
> > +  0x0000000094939291,
> > +  0x00000000a4a3a2a1,
> > +  0x00000000b4b3b2b1,
> > +  0x00000000c4c3c2c1,
> > +  0x00000000d4d3d2d1,
> > +  0x00000000e4e3e2e1,
> > +  0x00000000f4f3f2f1,
> > +};
> > +
> > +int
> > +main (int argc, char **argv)
> > +{
> > +  asm ("mov 0(%0), %%r16\n\t"
> > +      "mov 8(%0), %%r17\n\t"
> > +      "mov 16(%0), %%r18\n\t"
> > +      "mov 24(%0), %%r19\n\t"
> > +      "mov 32(%0), %%r20\n\t"
> > +      "mov 40(%0), %%r21\n\t"
> > +      "mov 48(%0), %%r22\n\t"
> > +      "mov 56(%0), %%r23\n\t"
> > +      "mov 64(%0), %%r24\n\t"
> > +      "mov 72(%0), %%r25\n\t"
> > +      "mov 80(%0), %%r26\n\t"
> > +      "mov 88(%0), %%r27\n\t"
> > +      "mov 96(%0), %%r28\n\t"
> > +      "mov 104(%0), %%r29\n\t"
> > +      "mov 112(%0), %%r30\n\t"
> > +      "mov 120(%0), %%r31\n\t"
> > +      : /* no output operands */
> > +      : "r" (data)
> > +      : "r16", "r17", "r18", "r19", "r20", "r21", "r22", "r23",
> > +    "r24", "r25", "r26", "r27", "r28", "r29", "r30", "r31");
> > +
> > +  asm ("nop"); /* break here */
> > +
> > +  return 0;
> > +}
> 
> I suggest using 'long long' for data[], because on windows 'long' has always a
> size of 32bit.

Right, thank you for this feedback.
I'd prefer to use int64_t, would that be ok from your side?

Regards,
Christina
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