"show" functions should not throw an exception in part because it causes
the output of the commands "info set" and "show" to get truncated.
This fixes the following fails:
FAIL: gdb.base/default.exp: info set
FAIL: gdb.base/default.exp: show
gdb/ChangeLog:
* i386-tdep.c (i386_mpx_info_bounds): Don't call error, instead
use printf_unfiltered.
(set_mpx_cmd): Add missing trailing space to command string
literal.
(_initialize_i386_tdep): Give the "mpx" prefix command its
correct name.
bfd/
* elf64-ppc.c (toc_adjusting_stub_needed): Use the symbol value
plus addend rather than the original st_value when looking up
entries in opd->adjust.
ld/testsuite/
* ld-powerpc/tocopt6-inc.s, ld-powerpc/tocopt6a.s,
ld-powerpc/tocopt6b.s, ld-powerpc/tocopt6c.s,
ld-powerpc/tocopt6.d: New test.
* ld-powerpc/powerpc.exp (ppc64elftests): Add it.
Back in the day support for these processors was added, we probably
didn't want to waste PPC_OPCODE bits on minor variations. I've had a
complaint that disassembly of mfspr/mtspr was wrong for power8. This
patch fixes that problem.
Note that since -m860/-m850/-m821 are new gas options enabling the
mpc8xx specific mfspr/mtspr variants it is possible that this change
will break some mpc8xx assembly code. ie. you might need to modify
makefiles to pass -m860 to gas.
include/opcode/
* ppc.h (PPC_OPCODE_750, PPC_OPCODE_7450, PPC_OPCODE_860): Define.
opcodes/
* ppc-opc.c (PPC750, PPC7450, PPC860): Define using PPC_OPCODE_*.
* ppc-dis.c (ppc_opts): Add 821, 850 and 860 entries. Add
PPC_OPCODE_7450 to 7450 entry. Add PPC_OPCODE_750 to 750cl entry.
gas/
* config/tc-ppc.c (md_show_usage): Add -m821, -m850, -m860.
* doc/c-ppc.texi (PowerPC-Opts): Likewise.
gas/testsuite/
* gas/ppc/titan.d: Correct mfmcsrr0 disassembly.
This change adds support for backtracing through Renesas RX exception
frames.
Determination about the type of frame is made by scanning the
remainder of the function for a return instruction and then looking at
which, if any, return instruction is found. A normal RTS instruction
indicates that the frame is a normal frame. An RTFI instruction
indicates that it's a fast interrupt, and an RTE instruction indicates
that the frame is a (normal) exception frame. If no return instruction
is found within the scanned region - which can happen when the end of
the function cannot be found - it is assumed to be a normal frame.
I was able to test that normal prologue scanning still works by
disabling the dwarf2 sniffer. I've tested this code for normal
interrupts. The fast interrupt case has not been tested.
gdb/ChangeLog:
* rx-tdep.c (RX_USP_REGNUM, RX_BPC_REGNUM): New constants.
(enum rx_frame_type): New.
(struct rx_prologue): Add new field `frame_type'.
(rx_analyze_prologue): Add `frame_type' parameter. Cache this
parameter in the prologue struct. Add code for recording
locations of PC and PSW for fast interrupt and exception frames.
(rx_skip_prologue): Adjust call to rx_analyze_prologue.
(rx_analyze_frame_prologue): Add `frame_type' parameter.
(rx_frame_type): New function.
(rx_frame_base): Fetch frame type and pass it to rx_analyze_prologue.
(rx_frame_this_id): Rename parameter `this_prologue_cache' to
`this_cache'.
(rx_frame_prev_register): Rename parameter `this_prologue_cache' to
`this_cache'. Add cases for RX_FRAME_TYPE_EXCEPTION and
RX_FRAME_TYPE_FAST_INTERRUPT.
(normal_frame_p, exception_frame_p, rx_frame_sniffer_common)
(rx_frame_sniffer, rx_exception_sniffer): New functions.
(rx_frame_unwind): Use rx_frame_sniffer instead of
default_frame_sniffer.
(rx_frame_unwind): New unwinder.
(rx_gdbarch_init): Register new unwinder.
This change adds two flags types for the (Renesas RX) psw, bpsw, and
fpsw registers. As a result, symbolic flags are displayed for these
registers in the output of GDB's "info registers" command as well as
in output from other commands, such as "print".
gdb/ChangeLog:
* rx-tdep.c (RX_BPSW_REGNUM, RX_FPSW_REGNUM): New constants.
(struct gdbarch_tdep): Add fields rx_psw_type and rx_fpsw_type.
(rx_register_type): Add cases for RX_PSW_REGNUM, RX_BPSW_REGNUM,
and RX_FPSW_REGNUM.
(rx_gdbarch_init): Initialize PSW, BPSW, and FPSW flags types.
At least on
gcc-4.4.7-11.el6.i686
./configure --enable-64-bit-bfd --enable-targets=all
GDB does not build due to:
cc1: warnings being treated as errors
s390-linux-tdep.c: In function ‘s390_handle_arg’:
s390-linux-tdep.c:2575: error: ‘val’ may be used uninitialized in this function
gdb/ChangeLog
2015-07-02 Jan Kratochvil <jan.kratochvil@redhat.com>
Fix GCC false warning.
* s390-linux-tdep.c (s390_handle_arg): Initialize VAL.
It should be "insert_hw_breakpoint" rather than "insert_hw_watchpoint".
gdb:
2015-07-02 Yao Qi <yao.qi@linaro.org>
* aarch64-linux-nat.c (aarch64_linux_insert_hw_breakpoint): Fix
typo in the debugging message.
Add maintenance commands that help debugging the btrace record target.
The following new commands are added:
maint info btrace
Print information about branch tracing internals.
maint btrace packet-history
Print the raw branch tracing data.
maint btrace clear-packet-history
Discard the stored raw branch tracing data.
maint btrace clear
Discard all branch tracing data. It will be fetched and processed
anew by the next "record" command.
maint set|show btrace pt skip-pad
Set and show whether PAD packets are skipped when computing the
packet history.
gdb/
* btrace.c: Include gdbcmd.h, cli/cli-utils.h, and ctype.h.
(maint_btrace_cmdlist, maint_btrace_set_cmdlist)
(maint_btrace_show_cmdlist, maint_btrace_pt_set_cmdlist)
(maint_btrace_pt_show_cmdlist, maint_btrace_pt_skip_pad)
(btrace_maint_clear): New.
(btrace_fetch, btrace_clear): Call btrace_maint_clear.
(pt_print_packet, btrace_maint_decode_pt)
(btrace_maint_update_pt_packets, btrace_maint_update_packets)
(btrace_maint_print_packets, get_uint, get_context_size, no_chunk)
(maint_btrace_packet_history_cmd)
(maint_btrace_clear_packet_history_cmd, maint_btrace_clear_cmd)
(maint_btrace_cmd, maint_btrace_set_cmd, maint_btrace_show_cmd)
(maint_btrace_pt_set_cmd, maint_btrace_pt_show_cmd)
(maint_info_btrace_cmd, _initialize_btrace): New.
* btrace.h (btrace_pt_packet, btrace_pt_packet_s)
(btrace_maint_packet_history, btrace_maint_info): New.
(btrace_thread_info) <maint>: New.
* NEWS: Announce it.
doc/
* gdb.texinfo (Maintenance Commands): Document "maint btrace"
commands.
Store the raw branch trace data that has been read from the target.
This data can be used for maintenance commands as well as for generating
a core file for the "record save" command.
gdb/
* btrace.c (btrace_fetch): Append the new trace data.
(btrace_clear): Clear the stored trace data.
* btrace.h (btrace_thread_info) <data>: New.
* common/btrace-common.h (btrace_data_clear)
(btrace_data_append): New.
* common/btrace-common.c (btrace_data_clear)
(btrace_data_append): New.
In struct perf_event_mmap_page there are new fields data_size and data_offset
that give the location of the perf_event data buffer relative to the mmap
page. Use them if they are present.
gdb/
* nat/linux-btrace.c (linux_enable_bts): Check for
PERF_ATTR_SIZE_VER5.
Check for data_offset and data_size fields. Use them.
Adds a new command "record btrace pt" to configure the kernel to use
Intel(R) Processor Trace instead of Branch Trace Strore.
The "record btrace" command chooses the tracing format automatically.
Intel(R) Processor Trace support requires Linux 4.1 and libipt.
gdb/
* NEWS: Announce new commands "record btrace pt" and "record pt".
Announce new options "set|show record btrace pt buffer-size".
* btrace.c: Include "rsp-low.h".
Include "inttypes.h".
(btrace_add_pc): Add forward declaration.
(pt_reclassify_insn, ftrace_add_pt, btrace_pt_readmem_callback)
(pt_translate_cpu_vendor, btrace_finalize_ftrace_pt)
(btrace_compute_ftrace_pt): New.
(btrace_compute_ftrace): Support BTRACE_FORMAT_PT.
(check_xml_btrace_version): Update version check.
(parse_xml_raw, parse_xml_btrace_pt_config_cpu)
(parse_xml_btrace_pt_raw, parse_xml_btrace_pt)
(btrace_pt_config_cpu_attributes, btrace_pt_config_children)
(btrace_pt_children): New.
(btrace_children): Add support for "pt".
(parse_xml_btrace_conf_pt, btrace_conf_pt_attributes): New.
(btrace_conf_children): Add support for "pt".
* btrace.h: Include "intel-pt.h".
(btrace_pt_error): New.
* common/btrace-common.c (btrace_format_string, btrace_data_fini)
(btrace_data_empty): Support BTRACE_FORMAT_PT.
* common/btrace-common.h (btrace_format): Add BTRACE_FORMAT_PT.
(struct btrace_config_pt): New.
(struct btrace_config)<pt>: New.
(struct btrace_data_pt_config, struct btrace_data_pt): New.
(struct btrace_data)<pt>: New.
* features/btrace-conf.dtd (btrace-conf)<pt>: New.
(pt): New.
* features/btrace.dtd (btrace)<pt>: New.
(pt, pt-config, cpu): New.
* nat/linux-btrace.c (perf_event_read, perf_event_read_all)
(perf_event_pt_event_type, kernel_supports_pt)
(linux_supports_pt): New.
(linux_supports_btrace): Support BTRACE_FORMAT_PT.
(linux_enable_bts): Free tinfo on error.
(linux_enable_pt): New.
(linux_enable_btrace): Support BTRACE_FORMAT_PT.
(linux_disable_pt): New.
(linux_disable_btrace): Support BTRACE_FORMAT_PT.
(linux_fill_btrace_pt_config, linux_read_pt): New.
(linux_read_btrace): Support BTRACE_FORMAT_PT.
* nat/linux-btrace.h (struct btrace_tinfo_pt): New.
(struct btrace_target_info)<pt>: New.
* record-btrace.c (set_record_btrace_pt_cmdlist)
(show_record_btrace_pt_cmdlist): New.
(record_btrace_print_pt_conf): New.
(record_btrace_print_conf): Support BTRACE_FORMAT_PT.
(btrace_ui_out_decode_error): Support BTRACE_FORMAT_PT.
(cmd_record_btrace_pt_start): New.
(cmd_record_btrace_start): Support BTRACE_FORMAT_PT.
(cmd_set_record_btrace_pt, cmd_show_record_btrace_pt): New.
(_initialize_record_btrace): Add new commands.
* remote.c (PACKET_Qbtrace_pt, PACKET_Qbtrace_conf_pt_size): New.
(remote_protocol_features): Add "Qbtrace:pt".
Add "Qbtrace-conf:pt:size".
(remote_supports_btrace): Support BTRACE_FORMAT_PT.
(btrace_sync_conf): Support PACKET_Qbtrace_conf_pt_size.
(remote_enable_btrace): Support BTRACE_FORMAT_PT.
(_initialize_remote): Add new commands.
gdbserver/
* linux-low.c: Include "rsp-low.h"
(linux_low_encode_pt_config, linux_low_encode_raw): New.
(linux_low_read_btrace): Support BTRACE_FORMAT_PT.
(linux_low_btrace_conf): Support BTRACE_FORMAT_PT.
(handle_btrace_enable_pt): New.
(handle_btrace_general_set): Support "pt".
(handle_btrace_conf_general_set): Support "pt:size".
doc/
* gdb.texinfo (Process Record and Replay): Spell out that variables
and registers are not available during btrace replay.
Describe the new "record btrace pt" command.
Describe the new "set|show record btrace pt buffer-size" options.
(General Query Packets): Describe the new Qbtrace:pt and
Qbtrace-conf:pt:size packets.
Expand "bts" to "Branch Trace Store".
Update the branch trace DTD.
Check for libipt, an Intel(R) Processor Trace decoder library. The sources
can be found on github at:
https://github.com/01org/processor-trace
gdb/
* configure.ac: Check for libipt
* configure: Regenerate.
* config.in: Regenerate.
* Makefile.in (LIBIPT): New.
(CLIBS): Add $LIBIPT.
* NEWS: document new configure options
It was found that from
(gdb) set debug compile 1
(gdb) compile code 1
[...]
allocated 0x7f bytes at 0x7ffff7ff9000 prot 5
allocated 0x38 bytes at 0x7ffff7ff8000 prot 1
lookup undefined ELF symbol "_GLOBAL_OFFSET_TABLE_"
allocated 0x10 bytes at 0x7ffff7ff7000 for registers
(gdb) _
the message 'lookup undefined ELF symbol' looks as an error to people,
including to myself once.
Change it to:
allocated 0x7f bytes at 0x7ffff7ff9000 prot 5
allocated 0x38 bytes at 0x7ffff7ff8000 prot 1
ELF symbol "_GLOBAL_OFFSET_TABLE_" relocated to zero
allocated 0x10 bytes at 0x7ffff7ff7000 for registers
(gdb) _
gdb/ChangeLog
2015-07-02 Jan Kratochvil <jan.kratochvil@redhat.com>
* compile/compile-object-load.c (compile_object_load): Replace debug
message "lookup undefined ELF symbol" by 3 more specific messages.
For the Renesas rl78 architecture, associate a flags type with the PSW
register. This will cause symbolic flags to be printed when using
the "info registers" command.
gdb/ChangeLog:
* rl78-tdep.c (struct gdbarch_tdep): Add new field, rl78_psw_type.
(rl78_register_type): Add case for RL78_PSW_REGNUM.
(rl78_gdbarch_init): Initialize rl78_psw_type.
When I replaced TUI's frame_changed hook to fix PR tui/13378 I assumed
that there's no reason to refresh register information following a call
to "up", "down" or "frame". This assumption was made to fix the problem
of refreshing frame information twice following a sync-execution normal
stop (once in tui_normal_stop and then in tui_before_prompt) -- the
second refresh removing any highlights made by the first.
I was wrong about that -- GDB's snapshot of register information is
per-frame, and when the frame changes, registers do too (most
prominently the %rip and %rsp registers). So e.g. GDB 7.8 would
highlight such register changes after invoking "up", "down" or "frame",
and current GDB does not.
To fix this regression, this patch adds another (sufficient) condition
for refreshing register information: in
tui_refresh_frame_and_register_information, always refresh register
information if frame information has changed. This makes register
information get refreshed following a call to "up", "down" or "frame"
while still avoiding the "double refresh" issue following a normal stop.
This condition may seem to obsolete the existing registers_too_p
parameter, but it does not: following a normal stop, it is possible that
registers may have changed while frame information had not. We could be
on the exact same PC with different register values. The new condition
would not catch such a case, but the registers_too_p condition will. So
both conditions seem necessary (and either one is sufficient).
gdb/ChangeLog:
* tui/tui-hooks.c (tui_refresh_frame_and_register_information):
Update commentary. Always refresh the registers when frame
information has changed.
* tui/tui-stack.c (tui_show_frame_info): Update commentary.
Change return type to int. Return 1 if frame information has
changed, 1 otherwise.
(tui_before_prompt): Update commentary.
* tui/tui-stack.h (tui_show_frame_info): Change return type to
int.
As these characters don't need to be escaped for strings
wrapped inside {} braces, we can remove the unneeded backslashes.
gdb/testsuite/ChangeLog:
* lib/gdb.exp (test_class_help): Remove the unneeded escaping of
'[' and ']' characters.
The select_frame hook is used by TUI to update TUI's frame and register
information following changes to the selected frame. The problem with
this hook is that it gets called after every single frame change, even
if the frame change is only temporary or internal. This is the primary
cause of flickering and slowdown when running the inferior under TUI
with conditional breakpoints set. Internal GDB events are the source of
many calls to select_frame and these internal events are triggered
frequently, especially when a few conditional breakpoints are set.
This patch removes the select_frame hook altogether and instead makes
the frame and register information get updated in two key places (using
observers): after an inferior stops, and right before displaying a
prompt. The latter hook covers the case when frame information must be
updated following a call to "up", "down" or "frame", and the former
covers the case when frame and register information must be updated
after a call to "continue", "step", etc. or after the inferior stops in
async execution mode. Together these hooks should cover all the cases
when frame information ought to be refreshed (and when the relevant
windows ought to be subsequently updated).
The print_frame_info_listing hook is also effectively obsolete now, but
it still must be set while the TUI is active because its caller
print_frame_info will otherwise assume that the CLI is active, and will
print the frame informaion accordingly. So this patch also sets the
print_frame_info_listing hook to a dummy callback, in lieu of outright
removing it yet.
Effectively, with this patch, frame/PC changes that do not immediately
precede an inferior-stop event or a prompt display event no longer cause
TUI's frame and register information to be updated.
And as a result of this change and of the previous change to
tui_show_frame_info, the TUI is much more disciplined about updating the
screen, and so the flicker as described in the PR is totally gone.
gdb/ChangeLog:
PR tui/13378
* frame.c (select_frame): Remove reference to
deprecated_selected_frame_level_changed_hook.
* frame.h (deprecated_selected_frame_level_changed_hook): Remove
declaration.
* stack.c (deprecated_selected_frame_level_changed_hook):
Likewise.
* tui/tui-hooks.c (tui_selected_frame_level_changed_hook):
Rename to ...
(tui_refresh_frame_and_register_information): ... this. Bail
out if there is no stack. Don't update register information
unless registers_too_p is true.
(tui_print_frame_info_listing_hook): Rename to ...
(tui_dummy_print_frame_info_listing_hook): ... this.
(tui_before_prompt): New function.
(tui_normal_stop): New function.
(tui_before_prompt_observer): New observer.
(tui_normal_stop_observer): New observer.
(tui_install_hooks): Set
deprecated_print_frame_info_listing_hook to
tui_dummy_print_frame_info_listing_hook. Register
tui_before_prompt_observer to call tui_before_prompt and
tui_normal_stop_observer to call tui_normal_stop. Remove
reference to deprecated_selected_frame_level_changed_hook.
(tui_remove_hooks): Detach and unset tui_before_prompt_observer
and tui_normal_stop_observer. Remove reference to
deprecated_selected_frame_level_changed_hook.
tui_show_frame_info is responsible for updating the visible windows
following a change in frame information (that being the currently
selected frame, PC, line number, etc). Currently it always redraws and
refreshes each window even if frame information has not changed. This
behavior is inefficient and helps contribute to the occassional
flickering of the TUI as described in the mentioned PR.
This patch makes tui_show_frame_info refresh the windows only if frame
information has changed. Determining whether frame information has
changed is done indirectly by determining whether the locator has
changed. This approach is convenient and yet sensible because the
locator contains all the relevant info we need to check anyway: the
current PC, the line number, the name of the executable and the name of
the current function. Probably only the PC is really necessary to
check, but it doesn't hurt to check every field.
Effectively, with this patch, consecutive calls to select_frame with the
same frame/PC no longer cause TUI's frame information to be updated
multiple times.
gdb/ChangeLog:
PR tui/13378
* tui/tui-stack.c (tui_set_locator_info): Change prototype to
return an int instead of void. Return whether the locator
window has changed.
(tui_show_frame_info): If the locator info has not changed, then
bail out early to avoid refreshing the windows.
The call to tui_alloc_content in tui_set_locator_info passes
locator->type as the type of the window whose content is being
allocated. This may seem correct but it's actually not because when
this code path actually get executed locator->type has not yet been to
set LOCATOR_WIN so it defaults to 0 i.e. SRC_WIN. Thus we allocate the
content of the locator window as if it was the source window. This
oversight turns out not to be a big deal in practice but the patch that
follows depends on the locator's proc_name and full_name arrays to be
initialized to the empty string which is done by tui_alloc_content if
we pass to it LOCATOR_WIN.
This patch fixes this bug by explicitly passing LOCATOR_WIN to
tui_alloc_content.
gdb/ChangeLog:
* tui/tui-stack.c (tui_set_locator_info): Explicitly pass
LOCATOR_WIN to tui_alloc_content.
This patch fixes PR 18605 which is about incorrectly decoding media
instructions in software single step.
gdb:
2015-06-30 Yao Qi <yao.qi@linaro.org>
PR tdep/18605
* arm-tdep.c (arm_get_next_pc_raw): Break for media
instructions.
This change turns on dwarf2 unwinding in rx-tdep.c. I found it
necessary to add rx_dwarf_reg_to_regnum in order to cause PC to be
mapped correctly.
gdb/ChangeLog:
* rx-tdep.c (RX_PSW_REGNUM): New enum constant.
(rx_dwarf_reg_to_regnum): New function.
(rx_gdbarch_init): Register rx_dwarf_reg_to_regnum. Use dwarf2
unwinding.
The crash reason is that the insn to be moved to stub may be a
relocation spot, so instead of placing the origin insn (that is insn
before-relocation) to the stub, I have to place the relocated one.
Note the relocation involved is non-pc-relative, so it is safe to move
the relocated insn.
gold/ChangeLog:
2015-06-29 Han Shen <shenhan@google.com>
* AArch64.cc (Erratum_stub::Insn_utilities): New typedef.
(Erratum_stub::update_erratum_insn): New method.
(Stub_table::relocate_stubs): Modified to place relocated insn.
(AArch64_relobj::fix_errata): Modified gold_assert.
Refs:
https://sourceware.org/ml/gdb/2015-03/msg00024.htmlhttps://sourceware.org/ml/gdb/2015-06/msg00005.html
On GNU/Linux, if an infcall spawns a thread, that thread ends up with
stuck running state. This happens because:
- when linux-nat.c detects a new thread, it marks them as running,
and does not report anything to the core.
- we skip finish_thread_state when the thread that is running the
infcall stops.
As result, that new thread ends up with stuck "running" state, even
though it really is stopped.
On Windows, _all_ threads end up stuck in running state, not just the
one that was spawned. That happens because when a new thread is
detected, unlike linux-nat.c, windows-nat.c reports
TARGET_WAITKIND_SPURIOUS to infrun. It's the fact that that event
does not cause a user-visible stop that triggers the problem. When
the target is re-resumed, we call set_running with a wildcard ptid,
which marks all thread as running. That set_running is not suppressed
because the (leader) thread being resumed does not have in_infcall
set. Later, when the infcall finally finishes successfully, nothing
marks all threads back to stopped.
We can trigger the same problem on all targets by having a thread
other than the one that is running the infcall report a breakpoint hit
to infrun, and then have that breakpoint not cause a stop. That's
what the included test does.
The fix is to stop GDB from suppressing the set_running calls while
doing an infcall, and then set the threads back to stopped when the
call finishes, iff they were originally stopped before the infcall
started. (Note the MI *running/*stopped event suppression isn't
affected.)
Tested on x86_64 GNU/Linux.
gdb/ChangeLog:
2015-06-29 Pedro Alves <palves@redhat.com>
PR threads/18127
* infcall.c (run_inferior_call): On infcall success, if the thread
was marked stopped before, reset it back to stopped.
* infrun.c (resume): Don't suppress the set_running calls when
doing an infcall.
(normal_stop): Only discard the finish_thread_state cleanup if the
infcall succeeded.
gdb/testsuite/ChangeLog:
2015-06-29 Pedro Alves <palves@redhat.com>
PR threads/18127
* gdb.threads/hand-call-new-thread.c: New file.
* gdb.threads/hand-call-new-thread.c: New file.
This patch lets GDBServer handle software breakpoints instead of relying
on GDB.
gdb/gdbserver/ChangeLog:
* linux-aarch64-low.c (aarch64_supports_z_point_type): Enable for
Z_PACKET_SW_BP.
GDB uses a "brk #0" instruction to perform a software breakpoint while
GDBServer uses an illegal instruction. Both instructions should match.
When enabling support for the 'Z0' packet, we let GDBServer insert the
breakpoint instruction instead of GDB. And in case of permanent
breakpoints for example, GDB will check if a breakpoint is inserted in the
inferior with `program_breakpoint_here_p (gdbarch, address)', and
compare the instruction read from the inferior with the breakpoint
instruction.
On AArch64, instructions are always little endian so we need to
represent it as an array of bytes, as done in aarch64-tdep.c.
gdb/gdbserver/ChangeLog:
* linux-aarch64-low.c: Remove comment about endianness.
(aarch64_breakpoint): Change type to gdb_byte[]. Set to "brk #0".
(aarch64_breakpoint_at): Change type of insn to gdb_byte[]. Use
memcmp.
