I found this const/not const mixup found by building in C++ mode.
gdb/ChangeLog:
* ada-lang.c (ada_search_struct_field): Constify parameters
and/or variables..
(xget_renaming_scope): Likewise.
(ada_is_redundant_range_encoding): Likewise.
(scan_discrim_bound): Likewise.
(to_fixed_range_type): Likewise.
This fixes the instruction format for 3 of the compare and branch
extended mnemonics. That way the extended mnemonics are actually
being found by objdump.
gas/testsuite/ChangeLog:
2015-09-10 Andreas Krebbel <krebbel@linux.vnet.ibm.com>
* gas/s390/zarch-z10.d: Fix testcase for some of the compare and
branch extended mnemonics.
opcodes/ChangeLog:
2015-09-10 Andreas Krebbel <krebbel@linux.vnet.ibm.com>
* s390-opc.txt: Fix instruction format of crj*, clrj*, and clgrj*.
This is cleanup only.
opcodes/ChangeLog:
2015-09-10 Andreas Krebbel <krebbel@linux.vnet.ibm.com>
* s390-opc.c: Remove unused (and broken) F_20 and FE_20 operand
types and adjust numbering accordingly. Fix some comments.
This makes objdump to be able to recognize some of the extended
mnemonics more often. It does not lead to wrong being generated.
opcodes/ChangeLog:
2015-09-10 Andreas Krebbel <krebbel@linux.vnet.ibm.com>
* s390-opc.c: Fix MASK_RIE_R0PI and MASK_RIE_R0PU.
gas/testsuite/ChangeLog:
2015-09-10 Andreas Krebbel <krebbel@linux.vnet.ibm.com>
* gas/s390/zarch-z10.d: Fix testcase for compare and branch
extended mnemonics.
Nowadays, GDB calls target_can_download_tracepoint at the entry of
download_tracepoint_locations, which is called by.
update_global_location_list. Sometimes, it is not needed to call
target_can_download_tracepoint at all because there is no tracepoint
created. In remote target, target_can_download_tracepoint send
qTStatus to the remote in order to know whether tracepoint can be
downloaded or not. This means some redundant qTStatus packets are
sent.
This patch is to teach GDB to call target_can_download_tracepoint
lazily, only on the moment there are tracepoint to download.
gdb.perf/single-step.exp (with a local patch to measure RSP packets)
shows the number of RSP packets is reduced because there is no
tracepoint at all, so GDB doesn't send qTStatus any more.
# of RSP packets
original patched
single-step rsp 1000 7000 6000
single-step rsp 2000 14000 12000
single-step rsp 3000 21000 18000
single-step rsp 4000 28000 24000
gdb:
2015-09-10 Yao Qi <yao.qi@linaro.org>
* breakpoint.c (download_tracepoint_locations): New local
can_download_tracepoint. Check the result of
target_can_download_tracepoint and save it in
can_download_tracepoint if there are tracepoints to download.
* linux-nat.h (enum tribool): Move it to ...
* common/common-types.h: ... here.
* strings.c: Add -s/--output-separator option to specify custom
separator string.
* NEWS: Mention the new feature.
* doc/binutils.text (strings): Document the new command line
option.
gdb/ChangeLog:
2015-09-09 Pedro Alves <palves@redhat.com>
* breakpoint.c: Include "thread-fsm.h".
(struct until_break_command_continuation_args): Delete.
(struct until_break_fsm): New.
(until_break_fsm_ops): New global.
(new_until_break_fsm, until_break_fsm_should_stop): New functions.
(until_break_command_continuation): Delete.
(until_break_fsm_clean_up): New function.
(until_break_fsm_async_reply_reason): New function.
(until_break_command): Adjust to create an until_break_fsm instead
of a continuation.
(momentary_bkpt_print_it): No longer print MI's async-stop-reason
here.
* infcmd.c (struct until_next_fsm): New.
(until_next_fsm_ops): New global.
(new_until_next_fsm, until_next_fsm_should_stop): New function.
(until_next_continuation): Delete.
(until_next_fsm_clean_up, until_next_fsm_async_reply_reason): New
functions.
(until_next_command): Adjust to create a new until_next_fsm
instead of a continuation.
This removes infcall-specific special casing from normal_stop,
simplifying it.
Like the "finish" command's, the FSM is responsible for storing the
function's return value.
gdb/ChangeLog:
2015-09-09 Pedro Alves <palves@redhat.com>
* infcall.c: Include thread_fsm.h.
(struct call_return_meta_info): New.
(get_call_return_value): New function, factored out from
call_function_by_hand_dummy.
(struct call_thread_fsm): New.
(call_thread_fsm_ops): New global.
(new_call_thread_fsm, call_thread_fsm_should_stop)
(call_thread_fsm_should_notify_stop): New functions.
(run_inferior_call): Add 'sm' parameter. Associate the FSM with
the thread.
(call_function_by_hand_dummy): Create a new call_thread_fsm
instance, associate it with the thread, and wait for the FSM to
finish. If finished successfully, fetch the function's result
value out of the FSM.
* infrun.c (fetch_inferior_event): If the FSM says the stop
shouldn't be notified, don't call normal_stop.
(maybe_remove_breakpoints): New function, factored out from ...
(normal_stop): ... here. Simplify.
* infrun.h (maybe_remove_breakpoints): Declare.
* thread-fsm.c (thread_fsm_should_notify_stop): New function.
(thread-fsm.h) <struct thread_fsm_ops>: New field.
(thread_fsm_should_notify_stop): Declare.
This adds an object oriented replacement for the "struct continuation"
mechanism, and converts the stepping commands (step, next, stepi,
nexti) and the "finish" commands to use it.
It adds a new thread "class" (struct thread_fsm) that contains the
necessary info and callbacks to manage the state machine of a thread's
execution command.
This allows getting rid of some hacks. E.g., in fetch_inferior_event
and normal_stop we no longer need to know whether a thread is doing a
multi-step (e.g., step N). This effectively makes the
intermediate_continuations unused -- they'll be garbage collected in a
separate patch. (They were never a proper abstraction, IMO. See how
fetch_inferior_event needs to check step_multi before knowing whether
to call INF_EXEC_CONTINUE or INF_EXEC_COMPLETE.)
The target async vs !async uiout hacks in mi_on_normal_stop go away
too.
print_stop_event is no longer called from normal_stop. Instead it is
now called from within each interpreter's normal_stop observer. This
clears the path to make each interpreter print a stop event the way it
sees fit. Currently we have some hacks in common code to
differenciate CLI vs TUI vs MI around this area.
The "finish" command's FSM class stores the return value plus that
value's position in the value history, so that those can be printed to
both MI and CLI's streams. This fixes the CLI "finish" command when
run from MI -- it now also includes the function's return value in the
CLI stream:
(gdb)
~"callee3 (strarg=0x400730 \"A string argument.\") at src/gdb/testsuite/gdb.mi/basics.c:35\n"
~"35\t}\n"
+~"Value returned is $1 = 0\n"
*stopped,reason="function-finished",frame=...,gdb-result-var="$1",return-value="0",thread-id="1",stopped-threads="all",core="0"
-FAIL: gdb.mi/mi-cli.exp: CLI finish: check CLI output
+PASS: gdb.mi/mi-cli.exp: CLI finish: check CLI output
gdb/ChangeLog:
2015-09-09 Pedro Alves <palves@redhat.com>
* Makefile.in (COMMON_OBS): Add thread-fsm.o.
* breakpoint.c (handle_jit_event): Print debug output.
(bpstat_what): Split event callback handling to ...
(bpstat_run_callbacks): ... this new function.
(momentary_bkpt_print_it): No longer handle bp_finish here.
* breakpoint.h (bpstat_run_callbacks): Declare.
* gdbthread.h (struct thread_info) <step_multi>: Delete field.
<thread_fsm>: New field.
(thread_cancel_execution_command): Declare.
* infcmd.c: Include thread-fsm.h.
(struct step_command_fsm): New.
(step_command_fsm_ops): New global.
(new_step_command_fsm, step_command_fsm_prepare): New functions.
(step_1): Adjust to use step_command_fsm_prepare and
prepare_one_step.
(struct step_1_continuation_args): Delete.
(step_1_continuation): Delete.
(step_command_fsm_should_stop): New function.
(step_once): Delete.
(step_command_fsm_clean_up, step_command_fsm_async_reply_reason)
(prepare_one_step): New function, based on step_once.
(until_next_command): Remove step_multi reference.
(struct return_value_info): New.
(print_return_value): Rename to ...
(print_return_value_1): ... this. New struct return_value_info
parameter. Adjust.
(print_return_value): Reimplement as wrapper around
print_return_value_1.
(struct finish_command_fsm): New.
(finish_command_continuation): Delete.
(finish_command_fsm_ops): New global.
(new_finish_command_fsm, finish_command_fsm_should_stop): New
functions.
(finish_command_fsm_clean_up, finish_command_fsm_return_value):
New.
(finish_command_continuation_free_arg): Delete.
(finish_command_fsm_async_reply_reason): New.
(finish_backward, finish_forward): Change symbol parameter to a
finish_command_fsm. Adjust.
(finish_command): Create a finish_command_fsm. Adjust.
* infrun.c: Include "thread-fsm.h".
(clear_proceed_status_thread): Delete the thread's FSM.
(infrun_thread_stop_requested_callback): Cancel the thread's
execution command.
(clean_up_just_stopped_threads_fsms): New function.
(fetch_inferior_event): Handle the event_thread's should_stop
method saying the command isn't done yet.
(process_event_stop_test): Run breakpoint callbacks here.
(print_stop_event): Rename to ...
(print_stop_location): ... this.
(restore_current_uiout_cleanup): New function.
(print_stop_event): Reimplement.
(normal_stop): No longer notify the end_stepping_range observers
here handle "step N" nor "finish" here. No longer call
print_stop_event here.
* infrun.h (struct return_value_info): Forward declare.
(print_return_value): Declare.
(print_stop_event): Change prototype.
* thread-fsm.c: New file.
* thread-fsm.h: New file.
* thread.c: Include "thread-fsm.h".
(thread_cancel_execution_command): New function.
(clear_thread_inferior_resources): Call it.
* cli/cli-interp.c (cli_on_normal_stop): New function.
(cli_interpreter_init): Install cli_on_normal_stop as normal_stop
observer.
* mi/mi-interp.c: Include "thread-fsm.h".
(restore_current_uiout_cleanup): Delete.
(mi_on_normal_stop): If the thread has an FSM associated, and it
finished, ask it for the async-reply-reason to print. Always call
print_stop_event here, regardless of the top-level interpreter.
Check bpstat_what to tell whether an asynchronous breakpoint hit
triggered.
* tui/tui-interp.c (tui_on_normal_stop): New function.
(tui_init): Install tui_on_normal_stop as normal_stop observer.
gdb/testsuite/ChangeLog:
2015-09-09 Pedro Alves <palves@redhat.com>
* gdb.mi/mi-cli.exp: Add CLI finish tests.
This patch makes the execution control code use largely the same
mechanisms in both sync- and async-capable targets. This means using
continuations and use the event loop to react to target events on sync
targets as well. The trick is to immediately mark infrun's event loop
source after resume instead of calling wait_for_inferior. Then
fetch_inferior_event is adjusted to do a blocking wait on sync
targets.
Tested on x86_64 Fedora 20, native and gdbserver, with and without
"maint set target-async off".
gdb/ChangeLog:
2015-09-09 Pedro Alves <palves@redhat.com>
* breakpoint.c (bpstat_do_actions_1, until_break_command): Don't
check whether the target can async.
* inf-loop.c (inferior_event_handler): Only call target_async if
the target can async.
* infcall.c: Include top.h and interps.h.
(run_inferior_call): For the interpreter to sync mode while
running the infcall. Call wait_sync_command_done instead of
wait_for_inferior plus normal_stop.
* infcmd.c (prepare_execution_command): Don't check whether the
target can async when running in the foreground.
(step_1): Delete synchronous case handling.
(step_once): Always install a continuation, even in sync mode.
(until_next_command, finish_forward): Don't check whether the
target can async.
(attach_command_post_wait, notice_new_inferior): Always install a
continuation, even in sync mode.
* infrun.c (mark_infrun_async_event_handler): New function.
(proceed): In sync mode, mark infrun's event source instead of
waiting for events here.
(fetch_inferior_event): If the target can't async, do a blocking
wait.
(prepare_to_wait): In sync mode, mark infrun's event source.
(infrun_async_inferior_event_handler): No longer bail out if the
target can't async.
* infrun.h (mark_infrun_async_event_handler): New declaration.
* linux-nat.c (linux_nat_wait_1): Remove calls to
set_sigint_trap/clear_sigint_trap.
(linux_nat_terminal_inferior): No longer check whether the target
can async.
* mi/mi-interp.c (mi_on_sync_execution_done): Update and simplify
comment.
(mi_execute_command_input_handler): No longer check whether the
target is async. Update and simplify comment.
* target.c (default_target_wait): New function.
* target.h (struct target_ops) <to_wait>: Now defaults to
default_target_wait.
(default_target_wait): Declare.
* top.c (wait_sync_command_done): New function, factored out from
...
(maybe_wait_sync_command_done): ... this.
* top.h (wait_sync_command_done): Declare.
* target-delegates.c: Regenerate.
This can also speedup the check as TLSDESC is the default model for
global/local dynamic that the big "||" check can finish more quickly
than putting them at the bottom.
2015-09-09 Jiong. Wang <jiong.wang@arm.com>
bfd/
* elfnn-aarch64.c (IS_AARCH64_TLS_RELAX_RELOC): Sort alphabetically.
This is a NOP change only relevant when reading the file or parsing it
with other tools.
opcodes/ChangeLog:
2015-09-09 Andreas Krebbel <krebbel@linux.vnet.ibm.com>
* s390-opc.c: Add OP32 definition.
* s390-opc.txt: Reduce the opcode padding of some extended
mnemonics from 6 to the actual length (which is 4).
For the BTS recording format, we sometimes get a FROM->TO record where the
FROM address lies in the kernel and the TO address lies in user space at
whatever address the user process was resumed.
GDB has a heuristic to filter out such records based on looking at the most
significant bit in the PC. This works fine for 64-bit systems but it doesn't
always work for 32-bit systems. Libraries that are loaded at fairly high
addresses might be mistaken for kernel code and branches inside the library
are filtered out.
Change the heuristic to (again heuristically) try to determine the lowest
address in kernel space. Any PC that is smaller than that should be in
user space.
On today's systems, there should be a symbol "_text" at that address.
Read /proc/kallsyms and search for that symbol.
It is not guaranteed that /proc/kallsyms is readable on all systems. On
64-bit systems, we fall back to check the most significant bit. On 32-bit
systems, we refrain from filtering out addresses.
The filtering should really be done by the kernel. And it soon will be:
https://lkml.org/lkml/2015/8/31/212.
gdb/
* nat/linux-btrace.h (struct btrace_target_info) <ptr_bits>: Remove.
* nat/linux-btrace.c: Include filestuff.h and inttypes.h.
Remove include of sys/utsname.h.
(linux_determine_kernel_ptr_bits): Remove.
(linux_determine_kernel_start): New.
(perf_event_is_kernel_addr): Remove tinfo argument. Update users.
Update check.
(perf_event_skip_bts_record): Remove tinfo argument. Update users.
(linux_enable_bts, linux_enable_pt): Remove tinfo->ptr_bits
initialization.
* x86-linux-nat.c (x86_linux_enable_btrace): Remove ptr_bits
assignment.
gdbserver/
* linux-low.c (linux_low_enable_btrace): Remove.
(linux_target_ops): Replace linux_low_enable_btrace with
linux_enable_btrace.
2015-09-08 Sandra Loosemore <sandra@codesourcery.com>
gdb/testsuite/
* gdb.threads/hand-call-in-threads.exp: Make sure the thread
command actually switches threads. Give up on remaining
tests if target fails to stop at breakpoint.
The new orphan handling tests added in commit c005eb9 fail on a range of
targets. Some of the failures were fixed in commit e32aa93 but not
all. This commit should address the remaining failures.
Update results to account for orphan sections being placed in different
orders, and for other, target specific sections, being discarded.
ld/testsuite/ChangeLog:
* ld-elf/orphan-7.map: Allow for other discarded sections.
* ld-elf/orphan-8.map: Updated to allow for different section
ordering on different targets.
* ld-elf/orphan.ld: Place .sbss section.
Building GDB in C++ mode on Fedora 20, the gdb/guile/ code shows ~280
errors like:
src/gdb/guile/guile.c:515:1: error: invalid conversion from ‘scm_unused_struct* (*)(SCM, SCM) {aka scm_unused_struct* (*)(scm_unused_struct*, scm_unused_struct*)}’ to ‘scm_t_subr {aka void*}’ [-fpermissive]
This commit fixes them all.
gdb/ChangeLog:
2015-09-07 Pedro Alves <palves@redhat.com>
* guile/guile-internal.h (as_a_scm_t_subr): New.
* guile/guile.c (misc_guile_functions): Use it.
* guile/scm-arch.c (arch_functions): Use it.
* guile/scm-block.c (block_functions, gdbscm_initialize_blocks):
Use it.
* guile/scm-breakpoint.c (breakpoint_functions): Use it.
* guile/scm-cmd.c (command_functions): Use it.
* guile/scm-disasm.c (disasm_functions): Use it.
* guile/scm-exception.c (exception_functions)
(private_exception_functions): Use it.
* guile/scm-frame.c (frame_functions)
* guile/scm-gsmob.c (gsmob_functions): Use it.
* guile/scm-iterator.c (iterator_functions): Use it.
* guile/scm-lazy-string.c (lazy_string_functions): Use it.
* guile/scm-math.c (math_functions): Use it.
* guile/scm-objfile.c (objfile_functions): Use it.
* guile/scm-param.c (parameter_functions): Use it.
* guile/scm-ports.c (port_functions, private_port_functions): Use
it.
* guile/scm-pretty-print.c (pretty_printer_functions): Use it.
* guile/scm-progspace.c (pspace_functions): Use it.
* guile/scm-string.c (string_functions): Use it.
* guile/scm-symbol.c (symbol_functions): Use it.
* guile/scm-symtab.c (symtab_functions): Use it.
* guile/scm-type.c (type_functions, gdbscm_initialize_types): Use
it.
* guile/scm-value.c (value_functions): Use it.
The previous commit to fix PR gold/18886 converted STT_IFUNC
to STT_FUNC when resolving to a symbol defined in a shared library.
This leads to an internal error if the shared library symbol is
seen first, as we do not convert the symbol at all.
We need to override the STT_IFUNC in add_from_dynobj() instead of
in override_base().
gold/
PR gold/18930
PR gold/18886
* resolve.cc (Symbol::override_base): Don't convert IFUNC symbols here.
* symtab.cc (Symbol_table::add_from_dynobj): Convert them here instead.
Replace the options --warn-orphan and --no-warn-orphan with a single
option --orphan-handling=MODE, where mode can be place, warn, error, and
discard.
Mode 'place' is the default, and is the current behaviour, placing the
orphan section into a suitable output section.
Mode 'warn' is the same as '--warn-orphan'. The orphan is also placed
using the same algorithm as for 'place'.
Mode 'error' is the same as '--warn-orphan' and '--fatal-warnings'.
Mode 'discard' assigns all output sections to the /DISCARD/ section.
ld/ChangeLog:
* ld.h (enum orphan_handling_enum): New.
(ld_config_type): Remove warn_orphan, add orphan_handling.
* ldemul.c (ldemul_place_orphan): Remove warning about orphan
sections.
* ldlang.c (ldlang_place_orphan): New function.
(lang_place_orphans): Call ldlang_place_orphan.
* ldlex.h (enum option_values): Remove OPTION_WARN_ORPHAN and
OPTION_NO_WARN_ORPHAN, add OPTION_ORPHAN_HANDLING.
* lexsup.c (ld_options): Remove 'warn-orphan' and
'no-warn-orphan', add 'orphan-handling'.
(parse_args): Remove handling for OPTION_WARN_ORPHAN and
OPTION_NO_WARN_ORPHAN, add handling for OPTION_ORPHAN_HANDLING.
* NEWS: Replace text about --warn-orphan with --orphan-handling.
* ld.texinfo (Options): Remove --warn-orphan entry and add
entry on --orphan-handling.
(Orphan Sections): Add reference to relevant command line options.
ld/testsuite/ChangeLog:
* ld-elf/elf.exp: Switch to rely on run_dump_test.
* ld-elf/orphan-5.l: Update expected output.
* ld-elf/orphan-5.d: New file.
* ld-elf/orphan-6.d: New file.
* ld-elf/orphan-6.l: New file.
* ld-elf/orphan-7.d: New file.
* ld-elf/orphan-7.map: New file.
* ld-elf/orphan-8.d: New file.
* ld-elf/orphan-8.map: New file.
In the following code:
struct symbol *wsym = (struct symbol *) NULL;
the cast of NULL is redundant, it adds noise, and is just one more thing
to change if the type of wsym ever changes. There are a relatively
small number of places in gdb where the above code pattern is used.
Usually the cast is removed like this:
struct symbol *wsym = NULL;
This commit updates all the places within the gdb/tui directory where we
cast NULL during assignment, removing the cast.
gdb/ChangeLog:
* tui/tui-data.c (win_with_focus): Remove cast of NULL pointer.
(tui_next_win): Likewise.
(tui_prev_win): Likewise.
(tui_partial_win_by_name): Likewise.
(tui_init_generic_part): Likewise.
(init_content_element): Likewise.
(tui_del_window): Likewise.
(tui_free_window): Likewise.
(tui_del_data_windows): Likewise.
(tui_free_data_content): Likewise.
* tui/tui-layout.c (make_source_or_disasm_window): Likewise.
* tui/tui-regs.c (tui_show_register_group): Likewise.
* tui/tui-win.c (tui_resize_all): Likewise.
(tui_set_focus): Likewise.
(tui_set_win_height): Likewise.
(make_invisible_and_set_new_height): Likewise.
* tui/tui-windata.c (tui_delete_data_content_windows): Likewise.
* tui/tui-wingeneral.c (make_visible): Likewise.
In the following code:
struct symbol *wsym = (struct symbol *) NULL;
the cast of NULL is redundant, it adds noise, and is just one more thing
to change if the type of wsym ever changes. There are a relatively
small number of places in gdb where the above code pattern is used.
Usually the cast is removed like this:
struct symbol *wsym = NULL;
This commit updates all the places within the gdb/cli directory where we
cast NULL during assignment, removing the cast.
gdb/ChangeLog:
* cli/cli-decode.c (find_cmd): Remove cast of NULL pointer.
In the following code:
struct symbol *wsym = (struct symbol *) NULL;
the cast of NULL is redundant, it adds noise, and is just one more thing
to change if the type of wsym ever changes. There are a relatively
small number of places in gdb where the above code pattern is used.
Usually the cast is removed like this:
struct symbol *wsym = NULL;
This commit updates all the places within the gdb/ directory where we
cast NULL during assignment, removing the cast.
gdb/ChangeLog:
* c-valprint.c (print_unpacked_pointer): Remove cast of NULL
pointer.
* dbxread.c (dbx_end_psymtab): Likewise.
* gnu-nat.c (gnu_write_inferior): Likewise.
* mdebugread.c (cross_ref): Likewise.
* p-valprint.c (pascal_val_print): Likewise.
* xcoffread.c (xcoff_end_psymtab): Likewise.
Before this change, trying to call an overloaded function with at least
one character literal in argument would fail. For instance, given these
two functions:
function F (C : Character) return Integer is
begin
return Character'Pos (C);
end F;
function F (I : Integer) return Integer is
begin
return -I;
end F;
We would get the following GDB session:
(gdb) p f('A')
$1 = -65
(gdb) p f(1)
$1 = -1
This is wrong because the first call should select the first F function
and thus return 65.
The root problem is that ada-lang.c:ada_language_arch_info stores in
string_char_type a type whose code is TYPE_CODE_INT instead of
TYPE_CODE_CHAR. As a result, all parsed character literals are turned
into integer values and during overload matching, the TYPE_CODE_CHAR
formal rejects the TYPE_CODE_INT actual.
This change turns string_char_type into a true TYPE_CODE_CHAR type in
ada-lang.c so that we have instead the expected:
(gdb) p f('A')
$1 = 65
gdb/ChangeLog:
* ada-lang.c (ada_language_arch_info): Create a TYPE_CODE_CHAR
type instead of a TYPE_CODE_INT one for the string_char_type
and the ada_primitive_type_char types.
gdb/testsuite/ChangeLog:
* gdb.ada/funcall_char.exp: New testcase.
* gdb.ada/funcall_char/foo.adb: New file.
Tested on x86_64-linux, no regression.
PR binutils/18879
* readelf.c (get_unwind_section_word): Check for negative offsets
and very small sections.
(dump_arm_unwind): Warn if the table offset is too large.
Nowadays, if user requests HW watchpoint to monitor a large memory area
or unaligned area, aarch64 GDB will split into multiple aligned areas,
and use multiple debugging registers to watch them. However, the
registers are not updated in a transaction way. GDBserver doesn't revert
updates in previous iterations if some debugging registers fail to update
due to some reason, like no free debugging registers available, in the
latter iteration. For example, if we have a char buf[34], and watch buf
in gdb,
(gdb) watch buf
Hardware watchpoint 2: buf
(gdb) c
Continuing.
infrun: clear_proceed_status_thread (Thread 13466)
infrun: proceed (addr=0xffffffffffffffff, signal=GDB_SIGNAL_DEFAULT)
infrun: step-over queue now empty
infrun: resuming [Thread 13466] for step-over
Sending packet: $m410838,22#35...Packet received: 00000000000000000000000000000000000000000000000000000000000000000000
infrun: skipping breakpoint: stepping past insn at: 0x400524
infrun: skipping breakpoint: stepping past insn at: 0x400524
Sending packet: $Z2,410838,22#80...Packet received: E01 <----- [1]
Packet Z2 (write-watchpoint) is supported
Sending packet: $Z0,7fb7fe0a8c,4#43...Packet received: OK
Warning:
Could not insert hardware watchpoint 2.
Could not insert hardware breakpoints:
You may have requested too many hardware breakpoints/watchpoints.
GDB receives E01 for Z2 packet [1] but GDBserver updates the debugging
register status,
insert_point (addr=0x00410838, len=34, type=hw-write-watchpoint):
BREAKPOINTs:
BP0: addr=0x0, ctrl=0x00000000, ref.count=0
BP1: addr=0x0, ctrl=0x00000000, ref.count=0
BP2: addr=0x0, ctrl=0x00000000, ref.count=0
BP3: addr=0x0, ctrl=0x00000000, ref.count=0
BP4: addr=0x0, ctrl=0x00000000, ref.count=0
BP5: addr=0x0, ctrl=0x00000000, ref.count=0
WATCHPOINTs:
WP0: addr=0x410850, ctrl=0x00001ff5, ref.count=1
WP1: addr=0x410848, ctrl=0x00001ff5, ref.count=1
WP2: addr=0x410840, ctrl=0x00001ff5, ref.count=1
WP3: addr=0x410838, ctrl=0x00001ff5, ref.count=1
four debugging registers can not monitor 34-byte long area, so the last
iteration of updating debugging register state fails but previous
iterations succeed. This makes GDB think no HW watchpoint is inserted
but some debugging registers are used.
This problem was exposed by "watch buf" gdb.base/watchpoint.exp with
aarch64 GDBserver debugging arm 32-bit program. The buf is 30-byte long
but 4-byte aligned, and four debugging registers can't cover 34-byte
(extend 4 bytes to be 8-byte aligned) area. However, this problem
does exist on non-multi-arch debugging scenario as well.
This patch moves code in aarch64_linux_region_ok_for_hw_watchpoint to
aarch64_linux_region_ok_for_watchpoint in nat/aarch64-linux-hw-point.c.
Then, checks with aarch64_linux_region_ok_for_watchpoint, like what we
are doing in GDB. If the region is OK, call aarch64_handle_watchpoint.
Regression tested on aarch64 with both 64-bit program and 32-bit
program. Some fails in gdb.base/watchpoint.exp are fixed.
gdb:
2015-09-03 Yao Qi <yao.qi@linaro.org>
* aarch64-linux-nat.c (aarch64_linux_region_ok_for_hw_watchpoint):
Move code to aarch64_linux_region_ok_for_watchpoint. Call
aarch64_linux_region_ok_for_watchpoint.
* nat/aarch64-linux-hw-point.c (aarch64_linux_region_ok_for_watchpoint):
New function.
* nat/aarch64-linux-hw-point.h (aarch64_linux_region_ok_for_watchpoint):
Declare it.
gdb/gdbserver:
2015-09-03 Yao Qi <yao.qi@linaro.org>
* linux-aarch64-low.c (aarch64_insert_point): Call
aarch64_handle_watchpoint if aarch64_linux_region_ok_for_watchpoint
returns true.
