Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Fixes: 56aebc89 ("Add GDB XML register description support")
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20231106185112.2755262-3-alex.bennee@linaro.org>

Since GDB 13.1(GDB commit ea3352172), GDB LoongArch changed to use
fcc0-7 instead of fcc register. This commit partially reverts commit
2f149c75 (`target/loongarch: Update gdb_set_fpu() and gdb_get_fpu()`)
to match the behavior of GDB.

Note that it is a breaking change for GDB 13.0 or earlier, but it is
also required for GDB 13.1 or later to work.

Signed-off-by: Jiajie Chen <c@jia.je>
Acked-by: Song Gao <gaosong@loongson.cn>
Message-Id: <20230808054315.3391465-1-c@jia.je>
Signed-off-by: Song Gao <gaosong@loongson.cn>

GPRs and PC are 32-bit wide in loongarch32 mode.

Signed-off-by: Jiajie Chen <c@jia.je>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Song Gao <gaosong@loongson.cn>
Message-ID: <20230817093121.1053890-4-gaosong@loongson.cn>
[PMD: Rebased, set gdb_num_core_regs]
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230821125959.28666-9-philmd@linaro.org>

Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Co-authored-by: Brian Cain <bcain@quicinc.com>
Signed-off-by: Brian Cain <bcain@quicinc.com>
Co-authored-by: Matheus Tavares Bernardino <quic_mathbern@quicinc.com>
Signed-off-by: Matheus Tavares Bernardino <quic_mathbern@quicinc.com>
Reviewed-by: Brian Cain <bcain@quicinc.com>
Message-Id: <17cb32f34d469f705c3cc066a3583935352ee048.1683214375.git.quic_mathbern@quicinc.com>

Signed-off-by: Matheus Tavares Bernardino <quic_mathbern@quicinc.com>
Reviewed-by: Taylor Simpson <tsimpson@quicinc.com>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Message-Id: <d25a3a79334d81f0e1ecfb438b6ee82585d02dc4.1683214375.git.quic_mathbern@quicinc.com>

Both TCG and KVM emulate ckc, cputm, last_break and prefix, and it's
quite useful to have them during debugging. Right now they are grouped
together with KVM-only pp, pfault_token, pfault_select and
pfault_compare in s390-virt.xml, and are not available when debugging
TCG-emulated code.

Move KVM-only registers into the new s390-virt-kvm.xml file. Advertise
s390-virt.xml always, and the new s390-virt-kvm.xml only for KVM.

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Message-Id: <20230314101813.174874-1-iii@linux.ibm.com>
Acked-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>

So that we can avoid the "older gdb crashes" problem described in
commit 5787d17a and which caused us to disable reporting pauth
information via the gdbstub, newer gdb is going to implement support
for recognizing the pauth information via a new feature name:
 org.gnu.gdb.aarch64.pauth_v2

Older gdb won't recognize this feature name, so we can re-enable the
pauth support under the new name without risking them crashing.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20230406150827.3322670-1-peter.maydell@linaro.org

The extension is primarily defined by the Linux kernel NT_ARM_PAC_MASK
ptrace register set.

The original gdb feature consists of two masks, data and code, which are
used to mask out the authentication code within a pointer.  Following
discussion with Luis Machado, add two more masks in order to support
pointers within the high half of the address space (i.e. TTBR1 vs TTBR0).

Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1105


Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20230227213329.793795-12-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

Mirroring the upstream gdb xml files, the two stack boundary
registers are separated out.

Reviewed-by: Edgar E. Iglesias <edgar@zeroasic.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

Before this commit, there were contradictory descriptions about size of EFER
register.
Line 113 says the size is 8 bytes.
Line 129 says the size is 4 bytes.

As a result, when GDB is debugging an OS running on QEMU, the GDB cannot
read 'g' packets correctly. This 'g' packet transmits values of each
registers of machine emulated by QEMU to GDB. QEMU, the packet sender,
assign 4 bytes for EFER in 'g' packet based on the line 113.
GDB, the packet receiver, extract 8 bytes for EFER in 'g' packet based on
the line 129. Therefore, all registers located behind EFER in 'g' packet
has been shifted 4 bytes in GDB.

After this commit, GDB can read 'g' packets correctly.

Signed-off-by: TaiseiIto <taisei1212@outlook.jp>
Message-Id: <TY0PR0101MB4285F637209075C9F65FCDA6A4479@TY0PR0101MB4285.apcprd01.prod.exchangelabs.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

The fixed register numbering in the various GDB feature files for
RISC-V only exists because these files were originally copied from the
GDB source tree.

However, the fixed numbering only exists in the GDB source tree so
that GDB, when it connects to a target that doesn't provide a target
description, will use a specific numbering scheme.

That numbering scheme is designed to be compatible with the first
versions of QEMU (for RISC-V), that didn't send a target description,
and relied on a fixed numbering scheme.

Because of the way that QEMU manages its target descriptions,
recording the number of registers in each feature, and just relying on
GDB's numbering starting from 0, then I propose that we remove all the
fixed numbering from the RISC-V feature xml files, and just rely on
the standard numbering scheme.  Plenty of other targets manage their
xml files this way, e.g. ARM, AArch64, Loongarch, m68k, rx, and s390.

Signed-off-by: Andrew Burgess <aburgess@redhat.com>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Palmer Dabbelt <palmer@rivosinc.com>
Message-Id: <6069395f90e6fc24dac92197be815fedf42f5974.1661934573.git.aburgess@redhat.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>

While testing some changes to GDB's handling for the RISC-V registers
fcsr, fflags, and frm, I spotted that QEMU includes these registers
twice in the target description it sends to GDB, once in the fpu
feature, and once in the csr feature.

Right now things basically work OK, QEMU maps these registers onto two
different register numbers, e.g. fcsr maps to both 68 and 73, and GDB
can use either of these to access the register.

However, GDB's target descriptions don't really work this way, each
register should appear just once in a target description, mapping the
register name onto the number GDB should use when accessing the
register on the target.  Duplicate register names actually result in
duplicate registers on the GDB side, however, as the registers have
the same name, the user can only access one of these registers.

Currently GDB has a hack in place, specifically for RISC-V, to spot
the duplicate copies of these three registers, and hide them from the
user, ensuring the user only ever sees a single copy of each.

In this commit I propose fixing this issue on the QEMU side, and in
the process, simplify the fpu register handling a little.

I think we should, remove fflags, frm, and fcsr from the two (32-bit
and 64-bit) fpu feature xml files.  These files will only contain the
32 core floating point register f0 to f31.  The fflags, frm, and fcsr
registers will continue to be advertised in the csr feature as they
currently are.

With that change made, I will simplify riscv_gdb_get_fpu and
riscv_gdb_set_fpu, removing the extra handling for the 3 status
registers.

Signed-off-by: Andrew Burgess <aburgess@redhat.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <0fbf2a5b12e3210ff3867d5cf7022b3f3462c9c8.1661934573.git.aburgess@redhat.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>

Rename loongarch-fpu64.xml to loongarch-fpu.xml and update
loongarch-fpu.xml to match upstream GDB [1]

[1]:https://github.com/bminor/binutils-gdb/blob/master/gdb/features/loongarch/fpu.xml



Signed-off-by: Song Gao <gaosong@loongson.cn>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Acked-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20220805033523.1416837-5-gaosong@loongson.cn>

Update loongarch-base64.xml to match the upstream GDB [1].

[1]:https://github.com/bminor/binutils-gdb/blob/master/gdb/features/loongarch/base64.xml



Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Song Gao <gaosong@loongson.cn>
Acked-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20220805033523.1416837-4-gaosong@loongson.cn>

GDB LoongArch add a register orig_a0, see the base64.xml [1].
We should add the orig_a0 to match the upstream GDB.

[1]: https://github.com/bminor/binutils-gdb/blob/master/gdb/features/loongarch/base64.xml



Signed-off-by: Song Gao <gaosong@loongson.cn>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Acked-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20220805033523.1416837-2-gaosong@loongson.cn>

Signed-off-by: Xiaojuan Yang <yangxiaojuan@loongson.cn>
Signed-off-by: Song Gao <gaosong@loongson.cn>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220606124333.2060567-42-yangxiaojuan@loongson.cn>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

Cortex-M CPUs with MVE should advertise this fact to gdb, using the
org.gnu.gdb.arm.m-profile-mve XML feature, which defines the VPR
register.  Presence of this feature also tells gdb to create
pseudo-registers Q0..Q7, so we do not need to tell gdb about them
separately.

Note that unless you have a very recent GDB that includes this fix:
http://patches-tcwg.linaro.org/patch/58133/

 gdb will mis-print the
individual fields of the VPR register as zero (but showing the whole
thing as hex, eg with "print /x $vpr" will give the correct value).

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20211101160814.5103-1-peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

Currently we send VFP XML which includes D0..D15 or D0..D31, plus
FPSID, FPSCR and FPEXC.  The upstream GDB tolerates this, but its
definition of this XML feature does not include FPSID or FPEXC.  In
particular, for M-profile cores there are no FPSID or FPEXC
registers, so advertising those is wrong.

Move FPSID and FPEXC into their own bit of XML which we only send for
A and R profile cores.  This brings our definition of the XML
org.gnu.gdb.arm.vfp feature into line with GDB's own (at least for
non-Neon cores...) and means we don't claim to have FPSID and FPEXC
on M-profile.

(It seems unlikely to me that any gdbstub users really care about
being able to look at FPEXC and FPSID; but we've supplied them to gdb
for a decade and it's not hard to keep doing so.)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210921162901.17508-5-peter.maydell@linaro.org

Now that we have switched to generate the RISC-V CSR XML dynamically,
remove the built-in hardcoded XML files.

Signed-off-by: Bin Meng <bin.meng@windriver.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-id: 20210116054123.5457-3-bmeng.cn@gmail.com
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>

This includes GDB hooks for reading from wnd wrtiting to AVR
registers, and xml register definition file as well.

[AM: Split a larger AVR introduction patch into logical units]
Suggested-by: Aleksandar Markovic <aleksandar.m.mail@gmail.com>
Co-developed-by: Michael Rolnik <mrolnik@gmail.com>
Co-developed-by: Sarah Harris <S.E.Harris@kent.ac.uk>
Signed-off-by: Michael Rolnik <mrolnik@gmail.com>
Signed-off-by: Sarah Harris <S.E.Harris@kent.ac.uk>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Aleksandar Markovic <aleksandar.m.mail@gmail.com>
Acked-by: Igor Mammedov <imammedo@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
[thuth: Fixed avr_cpu_gdb_read_register() parameter]
Signed-off-by: Thomas Huth <huth@tuxfamily.org>
Message-Id: <20200705140315.260514-7-huth@tuxfamily.org>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>

GDB's remote protocol requires M-profile cores to use the feature
name 'org.gnu.gdb.arm.m-profile' instead of the 'org.gnu.gdb.arm.core'
feature used for A- and R-profile cores. We weren't doing this, which
meant GDB treated our M-profile cores like A-profile ones. This mostly
doesn't matter, but for instance means that it doesn't correctly
handle backtraces where an M-profile exception frame is involved.

Ship a copy of GDB's arm-m-profile.xml and use it on the M-profile
cores.  The integer registers have the same offsets as the
arm-core.xml, but register 25 is the M-profile XPSR rather than the
A-profile CPSR, so we need to update arm_cpu_gdb_read_register() and
arm_cpu_gdb_write_register() to handle XSPR reads and writes.

Fixes: https://bugs.launchpad.net/qemu/+bug/1877136


Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 20200507134755.13997-1-peter.maydell@linaro.org

Currently "cf-core.xml" is sent to GDB when using any m68k flavor.  Thing is
it uses the "org.gnu.gdb.coldfire.core" feature name and gdb 8.3 then expects
a coldfire FPU instead of the default m68881 FPU.

This is not OK because the m68881 floats registers are 96 bits wide so it
crashes GDB with the following error message:

(gdb) target remote localhost:7960
Remote debugging using localhost:7960
warning: Register "fp0" has an unsupported size (96 bits)
warning: Register "fp1" has an unsupported size (96 bits)
...
Remote 'g' packet reply is too long (expected 148 bytes, got 180 bytes):    \
  00000000000[...]0000

With this patch: qemu-system-m68k -M none -cpu m68020 -s -S

(gdb) tar rem :1234
Remote debugging using :1234
warning: No executable has been specified and target does not support
determining executable automatically.  Try using the "file" command.
0x00000000 in ?? ()
(gdb) p $fp0
$1 = nan(0xffffffffffffffff)

Signed-off-by: KONRAD Frederic <frederic.konrad@adacore.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <1588094279-17913-3-git-send-email-frederic.konrad@adacore.com>
Message-Id: <20200430190122.4592-10-alex.bennee@linaro.org>

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
[PMD: Use newer QOM style, split cpu-qom.h, restrict access to
 extable array, use rx_cpu_tlb_fill() extracted from patch of
 Yoshinori Sato 'Convert to CPUClass::tlb_fill', call cpu_reset
 after qemu_init_vcpu, make rx_crname a function]
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Acked-by: Igor Mammedov <imammedo@redhat.com>
Message-Id: <20200224141923.82118-7-ysato@users.sourceforge.jp>
Acked-by: Richard Henderson <richard.henderson@linaro.org>
[PMD: Use GByteArray in gdbstub (rebase commit a010bdbe),
 use device_class_set_parent_reset (rebase commit 781c67ca)]
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>

This patch enables a debugger to read the current privilege level via a virtual
"priv" register. When compiled with CONFIG_USER_ONLY the register is still
visible but always reports the value zero.

Signed-off-by: Jonathan Behrens <jonathan@fintelia.io>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Bin Meng <bmeng.cn@gmail.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>

Signed-off-by: Jim Wilson <jimw@sifive.com>
Signed-off-by: Chih-Min Chao <chihmin.chao@sifive.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>

Signed-off-by: Jim Wilson <jimw@sifive.com>
Signed-off-by: Chih-Min Chao <chihmin.chao@sifive.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>

The machine description we send is being (silently) thrown on the floor
by GDB and GDB silently uses the default machine description, because
the xml parse fails on <feature> nested within <feature>.
Changes to the xml in qemu source code have no effect.

In addition, the default machine description has fs_base, which fails to
be retrieved, which breaks the whole register window.  Add it and the
other control registers.

Signed-off-by: Doug Gale <doug16k@gmail.com>
Message-Id: <20190124040457.2546-1-doug16k@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Let's provide the guarded storage registers via gdb server.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>

Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Message-Id: <20170620205121.26515-5-laurent@vivier.eu>

Add an XML description for SSE registers (XMM+MXCSR) for both X86
and X86-64 architectures in the GDB stub:
- configure: Define gdb_xml_files for the X86 targets (32 and 64bit).
- gdb-xml/i386-32bit-sse.xml & gdb-xml/i386-64bit-sse.xml: The XML files
that contain a description of the XMM + MXCSR registers.
- gdb-xml/i386-32bit.xml & gdb-xml/i386-64bit.xml: wrappers that include
the XML file of the core registers and the other XML file of the SSE registers.
- target/i386/cpu.c: Modify the gdb_core_xml_file to the new XML wrapper,
  modify the gdb_num_core_regs to fit the registers number defined in each
  XML file.

Signed-off-by: Abdallah Bouassida <abdallah.bouassida@lauterbach.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

This patch implements XML target description support for X86 and X86-64
architectures in the GDB stub, as the way with ARM and PowerPC:
- gdb-xml/32bit-core.xml & gdb-xml/64bit-core.xml: Adding the XML target
  description files, these files are picked from GDB source code.
- configure: Define gdb_xml_files for X86 targets.
- target/i386/cpu.c: Define gdb_core_xml_file and gdb_arch_name to add
  XML awareness for this architecture, modify the gdb_num_core_regs to
  fit the registers number defined in each XML file.

Signed-off-by: Abdallah Bouassida <abdallah.bouassida@lauterbach.com>
Message-Id: <2b3c8119-1602-28c7-eab4-296593877103@lauterbach.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Add the XML and functions to get and set VSX registers.

Signed-off-by: Anton Blanchard <anton@samba.org>
(fixed little-endian guests)
Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

Let's expose some virtual/fake registers as virtualization specific
registers.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Message-Id: <1443689387-34473-3-git-send-email-jfrei@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>

Let's support reading and writing of control registers for kvm and tcg.

We have to take care of flushing the tlb (tcg) and pushing the changed
registers into kvm.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>

Include the vector registers XML file that is provided by gdb,
and can be used by the qemu gdbserver interface.

Signed-off-by: Eric Farman <farman@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>

This patch adds the relevant s390x feature xml files taken from gdb.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>

Register the aarch64-fpu XML and implement the necessary
read/write handlers so we can support reading and writing
of FP registers in the gdb stub.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>

We want to be able to debug AArch64 guests. So let's add the respective gdb
stub functions and xml descriptions that allow us to do so.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: John Rigby <john.rigby@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1378235544-22290-12-git-send-email-peter.maydell@linaro.org
Message-id: 1368505980-17151-6-git-send-email-john.rigby@linaro.org
[PMM: dropped unused fp regs XML for now; moved 64 bit only functions
 to new gdbstub64.c; these are hooked up in AArch64CPU, not via
 ifdefs in ARMCPU]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

The powerpc xml files contained a hack--an empty, non-existent
register--for getting the register numbers to line up for
newer (XML-aware) and older (non-XML-aware) GDB.  While this hack worked
in some cases, it didn't work in all cases, notably when the user used
`finish' or `continue': GDB would attempt to read the non-existent
register and QEMU would complain.

This patch fixes things up properly.  Instead of inserting a fake
register, we explicitly declare the floating-point and SPE registers to
start at 71.  This action accomplishes the same thing as the nasty hack,
except that now GDB never tries to fetch the non-existant register 70.

Signed-off-by: Nathan Froyd <froydnj@codesourcery.com>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>

The current XML files claim, on floating point-supporting Power chips,
that $f0 is register 70.  This would be fine, except that register 70
for non-XML-aware GDB is FPSCR.  More importantly, 70 is less than
NUM_CORE_REGS (71) for Power, so a request for register 70 goes to the
"core" register reading routines, rather than the floating-point
register read routine we registered with gdb_register_coprocessor.

Therefore, when we are talking to an XML-aware GDB, we claim that
register has zero width, which causes the rest of QEMU's GDB stub to
send an error back to GDB, which causes GDB to be unable to read the
floating-point registers.  (The problem is also present for SPE
registers and occurs in a slightly different way for Altivec registers.)

The best way to fix this is to have the "core register" XML files for
PPC32 and PPC64 claim that there is a 4-byte register 70, which causes
$f0 to be register 71, and everything works just fine from that point
forward.

Signed-off-by: Nathan Froyd <froydnj@codesourcery.com>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6770 c046a42c-6fe2-441c-8c8c-71466251a162