I would like to be able to use non-trivial types in gdbarch_tdep types.
This is not possible at the moment (in theory), because of the one
definition rule.
To allow it, rename all gdbarch_tdep types to <arch>_gdbarch_tdep, and
make them inherit from a gdbarch_tdep base class. The inheritance is
necessary to be able to pass pointers to all these <arch>_gdbarch_tdep
objects to gdbarch_alloc, which takes a pointer to gdbarch_tdep.
These objects are never deleted through a base class pointer, so I
didn't include a virtual destructor. In the future, if gdbarch objects
deletable, I could imagine that the gdbarch_tdep objects could become
owned by the gdbarch objects, and then it would become useful to have a
virtual destructor (so that the gdbarch object can delete the owned
gdbarch_tdep object). But that's not necessary right now.
It turns out that RISC-V already has a gdbarch_tdep that is
non-default-constructible, so that provides a good motivation for this
change.
Most changes are fairly straightforward, mostly needing to add some
casts all over the place. There is however the xtensa architecture,
doing its own little weird thing to define its gdbarch_tdep. I did my
best to adapt it, but I can't test those changes.
Change-Id: Ic001903f91ddd106bd6ca09a79dabe8df2d69f3b
I noticed that gdbarch_selftest::operator() leaked the value returned by
gdbarch_printable_names. Make gdbarch_printable_names return an
std::vector and update callers. That makes it easier for everyone
involved, less manual memory management.
Change-Id: Ia8fc028bdb91f787410cca34f10bf3c5a6da1498
When the architecture supports memory tagging, we handle
pointer/reference types in a special way, so we can validate tags and
show mismatches.
Unfortunately, the currently implementation errors out when the user
prints non-address values: composite types, floats, references, member
functions and other things.
Vector registers:
(gdb) p $v0
Value can't be converted to integer.
Non-existent internal variables:
(gdb) p $foo
Value can't be converted to integer.
The same happens for complex types and printing struct/union types.
There are a few problems here.
The first one is that after print_command_1 evaluates the expression
to print, the tag validation code call value_as_address
unconditionally, without making sure we have have a suitable type
where it makes to sense to call it. That results in value_as_address
(if it isn't given a pointer-like type) trying to treat the value as
an integer and convert it to an address, which #1 - doesn't make sense
(i.e., no sense in validating tags after "print 1"), and throws for
non-integer-convertible types. We fix this by making sure we have a
pointer or reference type first, and only if so then proceed to check
if the address-like value has tags.
The second is that we're calling value_as_address even if we have an
optimized out or unavailable value, which throws, because the value's
contents aren't fully accessible/readable. This error currently
escapes out and aborts the print. This case is fixed by checking for
optimized out / unavailable explicitly.
Third, the tag checking process does not gracefully handle exceptions.
If any exception is thrown from the tag validation code, we abort the
print. E.g., the target may fail to access tags via a running thread.
Or the needed /proc files aren't available. Or some other untold
reason. This is a bit too rigid. This commit changes print_command_1
to catch errors, print them, and still continue with the normal
expression printing path instead of erroring out and printing nothing
useful.
With this patch, printing works correctly again:
(gdb) p $v0
$1 = {d = {f = {2.0546950501119882e-81, 2.0546950501119882e-81}, u = {3399988123389603631, 3399988123389603631}, s = {
3399988123389603631, 3399988123389603631}}, s = {f = {1.59329203e-10, 1.59329203e-10, 1.59329203e-10, 1.59329203e-10}, u = {
791621423, 791621423, 791621423, 791621423}, s = {791621423, 791621423, 791621423, 791621423}}, h = {bf = {1.592e-10,
1.592e-10, 1.592e-10, 1.592e-10, 1.592e-10, 1.592e-10, 1.592e-10, 1.592e-10}, f = {0.11224, 0.11224, 0.11224, 0.11224, 0.11224,
0.11224, 0.11224, 0.11224}, u = {12079, 12079, 12079, 12079, 12079, 12079, 12079, 12079}, s = {12079, 12079, 12079, 12079,
12079, 12079, 12079, 12079}}, b = {u = {47 <repeats 16 times>}, s = {47 <repeats 16 times>}}, q = {u = {
62718710765820030520700417840365121327}, s = {62718710765820030520700417840365121327}}}
(gdb) p $foo
$2 = void
(gdb) p 2 + 2i
$3 = 2 + 2i
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=28110
While reviewing another patch, I realized that gdbarch_info_init could
easily be removed in favor of initializing gdbarch_info fields directly
in the struct declaration. The only odd part is the union. I don't
know if it's actually important for it to be zero-initialized, but I
presume it is. I added a constructor to gdbarch_info to take care of
that. A proper solution would be to use std::variant. Or, these could
also be separate fields, the little extra space required wouldn't
matter.
gdb/ChangeLog:
* gdbarch.sh (struct gdbarch_info): Initialize fields, add
constructor.
* gdbarch.h: Re-generate.
* arch-utils.h (gdbarch_info_init): Remove, delete all usages.
* arch-utils.c (gdbarch_info_init): Remove.
Change-Id: I7502e08fe0f278d84eef1667a072e8a97bda5ab5
This field is not actually used, remove it.
gdb/ChangeLog:
* gdbarch.sh (struct gdbarch_info) <tdep_info>: Remove.
(gdbarch_find_by_info): Remove print.
* gdbarch.c, gdbarch.h: Re-generate.
Change-Id: I00af4681b8e1a27727441cbadc3827f5914bd8eb
This variable was made static in:
6bd434d6caa4 ("gdb: make some variables static")
But I modified gdbarch.c instead of gdbarch.sh, so the change was
later reverted when gdbarch.c was re-generated.
Do it right this time.
gdb/ChangeLog:
* gdbarch.sh (gdbarch_data_registry): Make static.
* gdbarch.c: Re-generate.
Change-Id: I4048ba99a0cf47acd9da050934965db222fbd159
We need some new gdbarch hooks to help us manipulate memory tags without having
to have GDB call the target methods directly.
This patch adds the following hooks:
gdbarch_memtag_to_string
--
Returns a printable string corresponding to the tag.
gdbarch_tagged_address_p
--
Checks if a particular address is protected with memory tagging.
gdbarch_memtag_matches_p
--
Checks if the logical tag of a pointer and the allocation tag from the address
the pointer points to matches.
gdbarch_set_memtags:
--
Sets either the allocation tag or the logical tag for a particular value.
gdbarch_get_memtag:
--
Gets either the allocation tag or the logical tag for a particular value.
gdbarch_memtag_granule_size
--
Sets the memory tag granule size, which represents the number of bytes a
particular allocation tag covers. For example, this is 16 bytes for
AArch64's MTE.
I've used struct value as opposed to straight CORE_ADDR so other architectures
can use the infrastructure without having to rely on a particular type for
addresses/pointers. Some architecture may use pointers of 16 bytes that don't
fit in a CORE_ADDR, for example.
gdb/ChangeLog:
2021-03-24 Luis Machado <luis.machado@linaro.org>
* arch-utils.c (default_memtag_to_string, default_tagged_address_p)
(default_memtag_matches_p, default_set_memtags)
(default_get_memtag): New functions.
* arch-utils.h (default_memtag_to_string, default_tagged_address_p)
(default_memtag_matches_p, default_set_memtags)
(default_get_memtag): New prototypes.
* gdbarch.c: Regenerate.
* gdbarch.h: Regenerate.
* gdbarch.sh (memtag_to_string, tagged_address_p, memtag_matches_p)
(set_memtags, get_memtag, memtag_granule_size): New gdbarch hooks.
(enum memtag_type): New enum.
This commits the result of running gdb/copyright.py as per our Start
of New Year procedure...
gdb/ChangeLog
Update copyright year range in copyright header of all GDB files.
Today, GDB only allows a single displaced stepping operation to happen
per inferior at a time. There is a single displaced stepping buffer per
inferior, whose address is fixed (obtained with
gdbarch_displaced_step_location), managed by infrun.c.
In the case of the AMD ROCm target [1] (in the context of which this
work has been done), it is typical to have thousands of threads (or
waves, in SMT terminology) executing the same code, hitting the same
breakpoint (possibly conditional) and needing to to displaced step it at
the same time. The limitation of only one displaced step executing at a
any given time becomes a real bottleneck.
To fix this bottleneck, we want to make it possible for threads of a
same inferior to execute multiple displaced steps in parallel. This
patch builds the foundation for that.
In essence, this patch moves the task of preparing a displaced step and
cleaning up after to gdbarch functions. This allows using different
schemes for allocating and managing displaced stepping buffers for
different platforms. The gdbarch decides how to assign a buffer to a
thread that needs to execute a displaced step.
On the ROCm target, we are able to allocate one displaced stepping
buffer per thread, so a thread will never have to wait to execute a
displaced step.
On Linux, the entry point of the executable if used as the displaced
stepping buffer, since we assume that this code won't get used after
startup. From what I saw (I checked with a binary generated against
glibc and musl), on AMD64 we have enough space there to fit two
displaced stepping buffers. A subsequent patch makes AMD64/Linux use
two buffers.
In addition to having multiple displaced stepping buffers, there is also
the idea of sharing displaced stepping buffers between threads. Two
threads doing displaced steps for the same PC could use the same buffer
at the same time. Two threads stepping over the same instruction (same
opcode) at two different PCs may also be able to share a displaced
stepping buffer. This is an idea for future patches, but the
architecture built by this patch is made to allow this.
Now, the implementation details. The main part of this patch is moving
the responsibility of preparing and finishing a displaced step to the
gdbarch. Before this patch, preparing a displaced step is driven by the
displaced_step_prepare_throw function. It does some calls to the
gdbarch to do some low-level operations, but the high-level logic is
there. The steps are roughly:
- Ask the gdbarch for the displaced step buffer location
- Save the existing bytes in the displaced step buffer
- Ask the gdbarch to copy the instruction into the displaced step buffer
- Set the pc of the thread to the beginning of the displaced step buffer
Similarly, the "fixup" phase, executed after the instruction was
successfully single-stepped, is driven by the infrun code (function
displaced_step_finish). The steps are roughly:
- Restore the original bytes in the displaced stepping buffer
- Ask the gdbarch to fixup the instruction result (adjust the target's
registers or memory to do as if the instruction had been executed in
its original location)
The displaced_step_inferior_state::step_thread field indicates which
thread (if any) is currently using the displaced stepping buffer, so it
is used by displaced_step_prepare_throw to check if the displaced
stepping buffer is free to use or not.
This patch defers the whole task of preparing and cleaning up after a
displaced step to the gdbarch. Two new main gdbarch methods are added,
with the following semantics:
- gdbarch_displaced_step_prepare: Prepare for the given thread to
execute a displaced step of the instruction located at its current PC.
Upon return, everything should be ready for GDB to resume the thread
(with either a single step or continue, as indicated by
gdbarch_displaced_step_hw_singlestep) to make it displaced step the
instruction.
- gdbarch_displaced_step_finish: Called when the thread stopped after
having started a displaced step. Verify if the instruction was
executed, if so apply any fixup required to compensate for the fact
that the instruction was executed at a different place than its
original pc. Release any resources that were allocated for this
displaced step. Upon return, everything should be ready for GDB to
resume the thread in its "normal" code path.
The displaced_step_prepare_throw function now pretty much just offloads
to gdbarch_displaced_step_prepare and the displaced_step_finish function
offloads to gdbarch_displaced_step_finish.
The gdbarch_displaced_step_location method is now unnecessary, so is
removed. Indeed, the core of GDB doesn't know how many displaced step
buffers there are nor where they are.
To keep the existing behavior for existing architectures, the logic that
was previously implemented in infrun.c for preparing and finishing a
displaced step is moved to displaced-stepping.c, to the
displaced_step_buffer class. Architectures are modified to implement
the new gdbarch methods using this class. The behavior is not expected
to change.
The other important change (which arises from the above) is that the
core of GDB no longer prevents concurrent displaced steps. Before this
patch, start_step_over walks the global step over chain and tries to
initiate a step over (whether it is in-line or displaced). It follows
these rules:
- if an in-line step is in progress (in any inferior), don't start any
other step over
- if a displaced step is in progress for an inferior, don't start
another displaced step for that inferior
After starting a displaced step for a given inferior, it won't start
another displaced step for that inferior.
In the new code, start_step_over simply tries to initiate step overs for
all the threads in the list. But because threads may be added back to
the global list as it iterates the global list, trying to initiate step
overs, start_step_over now starts by stealing the global queue into a
local queue and iterates on the local queue. In the typical case, each
thread will either:
- have initiated a displaced step and be resumed
- have been added back by the global step over queue by
displaced_step_prepare_throw, because the gdbarch will have returned
that there aren't enough resources (i.e. buffers) to initiate a
displaced step for that thread
Lastly, if start_step_over initiates an in-line step, it stops
iterating, and moves back whatever remaining threads it had in its local
step over queue to the global step over queue.
Two other gdbarch methods are added, to handle some slightly annoying
corner cases. They feel awkwardly specific to these cases, but I don't
see any way around them:
- gdbarch_displaced_step_copy_insn_closure_by_addr: in
arm_pc_is_thumb, arm-tdep.c wants to get the closure for a given
buffer address.
- gdbarch_displaced_step_restore_all_in_ptid: when a process forks
(at least on Linux), the address space is copied. If some displaced
step buffers were in use at the time of the fork, we need to restore
the original bytes in the child's address space.
These two adjustments are also made in infrun.c:
- prepare_for_detach: there may be multiple threads doing displaced
steps when we detach, so wait until all of them are done
- handle_inferior_event: when we handle a fork event for a given
thread, it's possible that other threads are doing a displaced step at
the same time. Make sure to restore the displaced step buffer
contents in the child for them.
[1] https://github.com/ROCm-Developer-Tools/ROCgdb
gdb/ChangeLog:
* displaced-stepping.h (struct
displaced_step_copy_insn_closure): Adjust comments.
(struct displaced_step_inferior_state) <step_thread,
step_gdbarch, step_closure, step_original, step_copy,
step_saved_copy>: Remove fields.
(struct displaced_step_thread_state): New.
(struct displaced_step_buffer): New.
* displaced-stepping.c (displaced_step_buffer::prepare): New.
(write_memory_ptid): Move from infrun.c.
(displaced_step_instruction_executed_successfully): New,
factored out of displaced_step_finish.
(displaced_step_buffer::finish): New.
(displaced_step_buffer::copy_insn_closure_by_addr): New.
(displaced_step_buffer::restore_in_ptid): New.
* gdbarch.sh (displaced_step_location): Remove.
(displaced_step_prepare, displaced_step_finish,
displaced_step_copy_insn_closure_by_addr,
displaced_step_restore_all_in_ptid): New.
* gdbarch.c: Re-generate.
* gdbarch.h: Re-generate.
* gdbthread.h (class thread_info) <displaced_step_state>: New
field.
(thread_step_over_chain_remove): New declaration.
(thread_step_over_chain_next): New declaration.
(thread_step_over_chain_length): New declaration.
* thread.c (thread_step_over_chain_remove): Make non-static.
(thread_step_over_chain_next): New.
(global_thread_step_over_chain_next): Use
thread_step_over_chain_next.
(thread_step_over_chain_length): New.
(global_thread_step_over_chain_enqueue): Add debug print.
(global_thread_step_over_chain_remove): Add debug print.
* infrun.h (get_displaced_step_copy_insn_closure_by_addr):
Remove.
* infrun.c (get_displaced_stepping_state): New.
(displaced_step_in_progress_any_inferior): Remove.
(displaced_step_in_progress_thread): Adjust.
(displaced_step_in_progress): Adjust.
(displaced_step_in_progress_any_thread): New.
(get_displaced_step_copy_insn_closure_by_addr): Remove.
(gdbarch_supports_displaced_stepping): Use
gdbarch_displaced_step_prepare_p.
(displaced_step_reset): Change parameter from inferior to
thread.
(displaced_step_prepare_throw): Implement using
gdbarch_displaced_step_prepare.
(write_memory_ptid): Move to displaced-step.c.
(displaced_step_restore): Remove.
(displaced_step_finish): Implement using
gdbarch_displaced_step_finish.
(start_step_over): Allow starting more than one displaced step.
(prepare_for_detach): Handle possibly multiple threads doing
displaced steps.
(handle_inferior_event): Handle possibility that fork event
happens while another thread displaced steps.
* linux-tdep.h (linux_displaced_step_prepare): New.
(linux_displaced_step_finish): New.
(linux_displaced_step_copy_insn_closure_by_addr): New.
(linux_displaced_step_restore_all_in_ptid): New.
(linux_init_abi): Add supports_displaced_step parameter.
* linux-tdep.c (struct linux_info) <disp_step_buf>: New field.
(linux_displaced_step_prepare): New.
(linux_displaced_step_finish): New.
(linux_displaced_step_copy_insn_closure_by_addr): New.
(linux_displaced_step_restore_all_in_ptid): New.
(linux_init_abi): Add supports_displaced_step parameter,
register displaced step methods if true.
(_initialize_linux_tdep): Register inferior_execd observer.
* amd64-linux-tdep.c (amd64_linux_init_abi_common): Add
supports_displaced_step parameter, adjust call to
linux_init_abi. Remove call to
set_gdbarch_displaced_step_location.
(amd64_linux_init_abi): Adjust call to
amd64_linux_init_abi_common.
(amd64_x32_linux_init_abi): Likewise.
* aarch64-linux-tdep.c (aarch64_linux_init_abi): Adjust call to
linux_init_abi. Remove call to
set_gdbarch_displaced_step_location.
* arm-linux-tdep.c (arm_linux_init_abi): Likewise.
* i386-linux-tdep.c (i386_linux_init_abi): Likewise.
* alpha-linux-tdep.c (alpha_linux_init_abi): Adjust call to
linux_init_abi.
* arc-linux-tdep.c (arc_linux_init_osabi): Likewise.
* bfin-linux-tdep.c (bfin_linux_init_abi): Likewise.
* cris-linux-tdep.c (cris_linux_init_abi): Likewise.
* csky-linux-tdep.c (csky_linux_init_abi): Likewise.
* frv-linux-tdep.c (frv_linux_init_abi): Likewise.
* hppa-linux-tdep.c (hppa_linux_init_abi): Likewise.
* ia64-linux-tdep.c (ia64_linux_init_abi): Likewise.
* m32r-linux-tdep.c (m32r_linux_init_abi): Likewise.
* m68k-linux-tdep.c (m68k_linux_init_abi): Likewise.
* microblaze-linux-tdep.c (microblaze_linux_init_abi): Likewise.
* mips-linux-tdep.c (mips_linux_init_abi): Likewise.
* mn10300-linux-tdep.c (am33_linux_init_osabi): Likewise.
* nios2-linux-tdep.c (nios2_linux_init_abi): Likewise.
* or1k-linux-tdep.c (or1k_linux_init_abi): Likewise.
* riscv-linux-tdep.c (riscv_linux_init_abi): Likewise.
* s390-linux-tdep.c (s390_linux_init_abi_any): Likewise.
* sh-linux-tdep.c (sh_linux_init_abi): Likewise.
* sparc-linux-tdep.c (sparc32_linux_init_abi): Likewise.
* sparc64-linux-tdep.c (sparc64_linux_init_abi): Likewise.
* tic6x-linux-tdep.c (tic6x_uclinux_init_abi): Likewise.
* tilegx-linux-tdep.c (tilegx_linux_init_abi): Likewise.
* xtensa-linux-tdep.c (xtensa_linux_init_abi): Likewise.
* ppc-linux-tdep.c (ppc_linux_init_abi): Adjust call to
linux_init_abi. Remove call to
set_gdbarch_displaced_step_location.
* arm-tdep.c (arm_pc_is_thumb): Call
gdbarch_displaced_step_copy_insn_closure_by_addr instead of
get_displaced_step_copy_insn_closure_by_addr.
* rs6000-aix-tdep.c (rs6000_aix_init_osabi): Adjust calls to
clear gdbarch methods.
* rs6000-tdep.c (struct ppc_inferior_data): New structure.
(get_ppc_per_inferior): New function.
(ppc_displaced_step_prepare): New function.
(ppc_displaced_step_finish): New function.
(ppc_displaced_step_restore_all_in_ptid): New function.
(rs6000_gdbarch_init): Register new gdbarch methods.
* s390-tdep.c (s390_gdbarch_init): Don't call
set_gdbarch_displaced_step_location, set new gdbarch methods.
gdb/testsuite/ChangeLog:
* gdb.arch/amd64-disp-step-avx.exp: Adjust pattern.
* gdb.threads/forking-threads-plus-breakpoint.exp: Likewise.
* gdb.threads/non-stop-fair-events.exp: Likewise.
Change-Id: I387cd235a442d0620ec43608fd3dc0097fcbf8c8
The last commit missed updating the doc of
gdbarch_displaced_step_hw_singlestep to avoid mentioning the removed
parameter, this one fixes it.
gdb/ChangeLog:
* gdbarch.sh (displaced_step_hw_singlestep): Adjust
documentation.
* gdbarch.h: Re-generate.
Change-Id: I33675d9a6c253443eee707e8285d16615ce20aaa
I noticed that the closure parameter of
gdbarch_displaced_step_hw_singlestep is never used by any
implementation of the method, so this patch removes it.
gdb/ChangeLog:
* gdbarch.sh (displaced_step_hw_singlestep): Remove closure
parameter.
* aarch64-tdep.c (aarch64_displaced_step_hw_singlestep):
Likewise.
* aarch64-tdep.h (aarch64_displaced_step_hw_singlestep):
Likewise.
* arch-utils.c (default_displaced_step_hw_singlestep):
Likewise.
* arch-utils.h (default_displaced_step_hw_singlestep):
Likewise.
* rs6000-tdep.c (ppc_displaced_step_hw_singlestep):
Likewise.
* s390-tdep.c (s390_displaced_step_hw_singlestep):
Likewise.
* gdbarch.c: Re-generate.
* gdbarch.h: Re-generate.
* infrun.c (resume_1): Adjust.
Change-Id: I7354f0b22afc2692ebff0cd700a462db8f389fc1
This patch starts by making the gdbarch_make_corefile_notes function
return a gdb::unique_xmalloc_ptr<char> and takes care of the fallouts,
mostly in linux-tdep.c and fbsd-tdep.c.
The difficulty in these files is that they use the BFD API for writing
core files, where you pass in a pointer to a malloc-ed buffer (or NULL
in the beginning), it re-allocs it if needed, and returns you the
possibly updated pointer. I therefore used this pattern everywhere:
note_data.reset (elfcore_write_note (obfd, note_data.release (), ...)
This hands over the ownership of note_data to the BFD function for the
duration of the call, and then puts its back in note_data right after
the call.
gdb/ChangeLog:
* gdbarch.sh (make_corefile_notes): Return unique pointer.
* gdbarch.c: Re-generate.
* gdbarch.h: Re-generate.
* gcore.c (write_gcore_file_1): Adjust.
* fbsd-tdep.c (struct fbsd_collect_regset_section_cb_data): Add
constructor.
<note_data>: Change type to unique pointer.
<abort_iteration>: Change type to bool.
(fbsd_collect_regset_section_cb): Adjust to unique pointer.
(fbsd_collect_thread_registers): Return void, adjust.
(struct fbsd_corefile_thread_data): Add construtor.
<note_data>: Change type to unique pointer.
(fbsd_corefile_thread): Adjust.
(fbsd_make_corefile_notes): Return unique pointer, adjust.
* linux-tdep.c (linux_make_mappings_corefile_notes): Change type
to unique pointer, adjust.
(struct linux_collect_regset_section_cb_data): Add constructor.
<note_data>: Change type to unique pointer.
<abort_iteration>: Change type to bool.
(linux_collect_thread_registers): Return void, adjust.
(struct linux_corefile_thread_data): Add constructor.
<note_data>: Change type to unique pointer.
(linux_corefile_thread): Adjust.
(linux_make_corefile_notes): Return unique pointer, adjust.
Change-Id: I1e03476bb47b87c6acb3e12204d193f38cc4e02b
gdbarch predicates (functions suffixed _p to check whether a gdbarch
implements a given method) currently return int. Make them return bool.
There is no expected behavior change.
gdb/ChangeLog:
* gdbarch.sh: Make generated predicates return bool.
* gdbarch.c: Re-generate.
* gdbarch.h: Re-generate.
Change-Id: Ie7ebc1acae62df83da9085ba69327fca551c5a30
A later patch in this series will rewrite enum_flags fixing some API
holes. That would cause build failures around code using
type_instance_flags. Or rather, that should be using it, but wasn't.
This patch fixes it by using type_instance_flags throughout instead of
plain integers.
Note that we can't make the seemingly obvious change to struct
type::instance_flags:
- unsigned instance_flags : 9;
+ ENUM_BITFIELD (type_instance_flag_value) instance_flags : 9;
Because G++ complains then that 9 bits isn't sufficient for holding
all values of type_instance_flag_value.
So the patch adds an type::instance_flags() method, which takes care
of casting appropriately, and adds a separate type::set_instance_flags
method, following the pattern of the ongoing TYPE_XXX macro
elimination. This converts uses of TYPE_INSTANCE_FLAGS to
type::instance_flags() in the places where the code was already being
touched, but there are still many references to the
TYPE_INSTANCE_FLAGS macro left behind. Those could/should be fully
replaced at some point.
gdb/ChangeLog:
* avr-tdep.c (avr_address_class_type_flags): Return
type_instance_flags.
(avr_address_class_type_flags_to_name): Take a
type_instance_flags.
(avr_address_class_name_to_type_flags): Return bool and take a
type_instance_flags.
* d-lang.c (build_d_types): Use type::set_instance_flags.
* ft32-tdep.c (ft32_address_class_type_flags): Return
type_instance_flags.
(ft32_address_class_type_flags_to_name): Take a
type_instance_flags.
(ft32_address_class_name_to_type_flags): Return bool and take a
type_instance_flags.
(ft32_gdbarch_init): Use type::set_instance_flags.
* eval.c (fake_method::fake_method): Use type::set_instance_flags.
* gdbarch.h, gdbarch.c: Regenerate.
* gdbarch.sh (address_class_type_flags): Use type_instance_flags.
(address_class_name_to_type_flags): Use type_instance_flags and
bool.
* gdbtypes.c (address_space_name_to_int)
(address_space_int_to_name, make_qualified_type): Use
type_instance_flags.
(make_qualified_type): Use type_instance_flags and
type::set_instance_flags.
(make_type_with_address_space, make_cv_type, make_vector_type)
(check_typedef): Use type_instance_flags.
(recursive_dump_type): Cast type_instance_flags to unsigned for
printing.
(copy_type_recursive): Use type::set_instance_flags.
(gdbtypes_post_init): Use type::set_instance_flags.
* gdbtypes.h (struct type) <instance_flags>: Rename to ...
<m_instance_flags>: ... this.
<instance_flags, set_instance_flags>: New methods.
(TYPE_INSTANCE_FLAGS): Use the instance_flags method.
(SET_TYPE_INSTANCE_FLAGS): New.
(address_space_name_to_int, address_space_int_to_name)
(make_type_with_address_space): Pass flags using
type_instance_flags instead of int.
* stabsread.c (cleanup_undefined_types_noname): Use
type::set_instance_flags.
* s390-tdep.c (s390_address_class_type_flags): Return
type_instance_flags.
(s390_address_class_type_flags_to_name): Take a
type_instance_flags.
(s390_address_class_name_to_type_flags): Return bool and take a
type_instance_flags.
* type-stack.c (type_stack::follow_types): Use
type_instance_flags.
* dwarf2/read.c (read_tag_pointer_type): Use type_instance_flags.
This adds support for the bfloat16 datatype, which can be seen as a short
version of FP32, skipping the least significant 16 bits of the mantissa.
Since the datatype is currently only supported by the AVX512 registers,
the printing of bfloat16 values is only supported for xmm, ymm and zmm
registers.
gdb/ChangeLog:
2020-09-11 Moritz Riesterer <moritz.riesterer@intel.com>
Felix Willgerodt <Felix.Willgerodt@intel.com>
* gdbarch.sh: Added bfloat16 type.
* gdbarch.c: Regenerated.
* gdbarch.h: Regenerated.
* gdbtypes.c (floatformats_bfloat16): New struct.
(gdbtypes_post_init): Add builtin_bfloat16.
* gdbtypes.h (struct builtin_type) <builtin_bfloat16>: New member.
(floatformats_bfloat16): New struct.
* i386-tdep.c (i386_zmm_type): Add field "v32_bfloat16"
(i386_ymm_type): Add field "v16_bfloat16"
(i386_gdbarch_init): Add set_gdbarch_bfloat16_format.
* target-descriptions.c (make_gdb_type): Add case TDESC_TYPE_BFLOAT16.
* gdbsupport/tdesc.cc (tdesc_predefined_types): New member bfloat16.
* gdbsupport/tdesc.h (tdesc_type_kind): New member TDESC_TYPE_BFLOAT16.
* features/i386/64bit-avx512.xml: Add bfloat16 type.
* features/i386/64bit-avx512.c: Regenerated.
* features/i386/64bit-sse.xml: Add bfloat16 type.
* features/i386/64bit-sse.c: Regenerated.
gdb/testsuite/ChangeLog:
2020-09-11 Moritz Riesterer <moritz.riesterer@intel.com>
Felix Willgerodt <Felix.Willgerodt@intel.com>
* x86-avx512bf16.c: New file.
* x86-avx512bf16.exp: Likewise.
* lib/gdb.exp (skip_avx512bf16_tests): New function.
The new gdbarch method, read_core_file_mappings, will be used for
reading file-backed mappings from a core file. It'll be used
for two purposes: 1) to construct a table of file-backed mappings
in corelow.c, and 2) for display of core file mappings.
For Linux, I tried a different approach in which knowledge of the note
format was placed directly in corelow.c. This seemed okay at first;
it was only one note format and the note format was fairly simple.
After looking at FreeBSD's note/mapping reading code, I concluded
that it's best to leave architecture specific details for decoding
the note in (architecture specific) tdep files.
With regard to display of core file mappings, I experimented with
placing the mappings display code in corelow.c. It has access to the
file-backed mappings which were read in when the core file was loaded.
And, better, still common code could be used for all architectures.
But, again, the FreeBSD mapping code convinced me that this was not
the best approach since it has even more mapping info than Linux.
Display code which would work well for Linux will leave out mappings
as well as protection info for mappings.
So, for these reasons, I'm introducing a new gdbarch method for
reading core file mappings.
gdb/ChangeLog:
* arch-utils.c (default_read_core_file_mappings): New function.
* arch-utils.c (default_read_core_file_mappings): Declare.
* gdbarch.sh (read_core_file_mappings): New gdbarch method.
* gdbarch.h, gdbarch.c: Regenerate.
This is a more general version of the existing handle_segmentation_fault
hook that is able to report information for an arbitrary signal, not
just SIGSEGV.
gdb/ChangeLog:
* gdbarch.c: Regenerate.
* gdbarch.h: Regenerate.
* gdbarch.sh (report_signal_info): New method.
* infrun.c (print_signal_received_reason): Invoke gdbarch
report_signal_info hook if present.
There are currently two remaining uses of deprecated_set_gdbarch_data,
both of which are needed because during gdbarch initialisation we call
gdbarch_data for a data field that is registered using:
gdbarch_data_register_post_init (....)
However, in both of these cases, the only thing that the call back
needs from the gdbarch struct is its obstack. Given this there is
nothing stopping us changing the post-init hooks into pre-init hooks.
The pre-init hooks don't get passed the full gdbarch, they only get
passed its obstack.
The IA64 change is completely untested. The user-regs change has been
tested a little by locally adding some user-regs to the x86-64 target,
and also by running the RISC-V tests, which do use user-regs.
gdb/ChangeLog:
* gdbarch.c: Regenerate.
* gdbarch.h: Regenerate.
* gdbarch.sh (deprecated_set_gdbarch_data): Delete.
(gdbarch_data): Use internal_error for the case where
deprecated_set_gdbarch_data was originally needed.
* ia64-libunwind-tdep.c (libunwind_descr_init): Update parameters,
and use passed in obstack.
(libunwind_frame_set_descr): Should no longer get back NULL from
gdbarch_data.
(_initialize_libunwind_frame): Register as a pre-init gdbarch data
type.
* user-regs.c (user_regs_init): Update parameters, and use passed
in obstack.
(user_reg_add): Should no longer get back NULL from gdbarch_data.
(_initialize_user_regs): Register as a pre-init gdbarch data type.
I spotted something that looks wrong in the doc of
gdbarch_displaced_step_copy_insn.
It says that if the function returns NULL, it means that it has emulated
the behavior of the instruction and written the result to REGS.
However, it says below that the function may return NULL to indicate
that the instruction can't be single-stepped out-of-line, in which case
the core steps the instruction in-line. The two are contradictory.
The right one is the latter, if the function returns NULL, the core
falls back to in-line stepping. I checked all the implementations of
this function and they all agree with this.
gdb/ChangeLog:
* gdbarch.sh (displaced_step_copy_insn): Update doc.
* gdbarch.h: Re-generate.
Change-Id: I98163cdd38970cde4c77680e249b10f5d2d5bf9b
gdbarch_static_transform_name is completely Solaris-specific or rather
specific to the Studio compilers. Studio cc has deprecated Stabs support
in the 12.4 release back in 2015, GCC has defaulted to DWARF-2 on Solaris
7+ since 2004 and Stabs themselves are pretty much obsolete, so the whole
code can go.
Tested on sparcv9-sun-solaris2.11 and x86_64-pc-linux-gnu with
--enable-targets=all.
* sol2-tdep.c (sol2_static_transform_name): Remove.
(sol2_init_abi): Don't register it.
* gdbarch.sh (static_transform_name): Remove.
* gdbarch.c, gdbarch.h: Regenerate.
* dbxread.c (read_dbx_symtab) <'S'>: Remove call to
gdbarch_static_transform_name.
* mdebugread.c (parse_partial_symbols) <'S'>: Likewise.
* stabsread.c (define_symbol) <'X'>: Remove.
(define_symbol) <'S'>: Remove gdbarch_static_transform_name
handling.
<'V'>: Likewise.
* xcoffread.c (scan_xcoff_symtab): Remove gdbarch.
<'S'>: Remove call to gdbarch_static_transform_name.
It was suggested in this thread [1] that gdbarch.sh should write to
gdbarch.h and gdbarch.c directly. This patch implements that.
When running gdbarch.sh, we currently need to move new-gdbarch.c over
gdbarch.c and new-gdbarch.h over gdbarch.h. It might have been useful
at some point to not have gdbarch.sh overwrite gdbarch.h and gdbarch.c,
but with git it's really unnecessary. Any changes to gdbarch.sh can be
inspected using `git diff`.
A next step would be to have the Makefile automatically run gdbarch.sh
if it sees that gdbarch.c and gdbarch.h are out of date. Or maybe even
remove gdbarch.c and gdbarch.h from the tree and generate them in the
build directory when building. But that requires more thinking and
discussions, and I think that this change is already useful in itself.
[1] https://sourceware.org/pipermail/gdb-patches/2020-May/168265.html
gdb/ChangeLog;
* gdbarch.sh: Write to gdbarch.c/gdbarch.h directly. Don't
compare old and new versions.
(compare_new): Remove.
Change-Id: I7970a9e8af0afc0145cb5a28e73d94fbaa1e25b9
shellcheck reports:
In gdbarch.sh line 53:
while IFS='' read line
^--^ SC2162: read without -r will mangle backslashes.
See the rationale at [1]. In our case, we actually want the backslashes
to be interpreted and removed. Silence the warning using a directive.
[1] https://github.com/koalaman/shellcheck/wiki/SC2162
gdb/ChangeLog:
* gdbarch.sh (do_read): Add shellcheck disable directive for
warning SC2162.
Fix all instances of this kind of warning:
In gdbarch.sh line 96:
m ) staticdefault="${predefault}" ;;
^-----------^ SC2154: predefault is referenced but not assigned.
These warnings appear because we are doing something a bit funky when reading
the gdbarch fields. These variables are not assigned explicitly, but
using some `eval` commands.
I don't think there is so much we can fix about those warnings. To
silence them, I've changed `${foo}` to `${foo:-}`. This tells the shell
to substitute with an empty string if `foo` is not defined. This
retains the current behavior, but the warnings go away.
gdb/ChangeLog:
* gdbarch.sh: Use ${foo:-} where shellcheck would report a
"referenced but not assigned" warning.
shellcheck reports:
In gdbarch.sh line 139:
fallbackdefault="0"
^-------------^ SC2034: fallbackdefault appears unused. Verify use (or export if used externally).
Indeed, the `fallbackdefault` variable appears to be unused, remove the
code that sets it.
gdb/ChangeLog:
* gdbarch.sh: Remove code that sets fallbackdefault.
Fix all warnings of this type:
In gdbarch.sh line 1238:
if [ "x${invalid_p}" = "x0" -a -n "${postdefault}" ]
^-- SC2166: Prefer [ p ] && [ q ] as [ p -a q ] is not well defined.
See the rationale here [1].
[1] https://github.com/koalaman/shellcheck/wiki/SC2166
gdb/ChangeLog:
* gdbarch.sh: Use shell operators && and || instead of
-a and -o.
Fix all instances of:
In gdbarch.sh line 2195:
printf " `echo "$function" | sed -e 's/./ /g'` %s %s)\n" "$returntype" "$function"
^-- SC2006: Use $(...) notation instead of legacy backticked `...`.
Did you mean:
printf " $(echo "$function" | sed -e 's/./ /g') %s %s)\n" "$returntype" "$function"
See here [1] for the rationale.
[1] https://github.com/koalaman/shellcheck/wiki/SC2006
gdb/ChangeLog:
* gdbarch.sh: Use $(...) instead of `...`.
Fix all instances of:
In gdbarch.sh line 31:
if test ! -r ${file}
^-----^ SC2086: Double quote to prevent globbing and word splitting.
Did you mean:
if test ! -r "${file}"
Note that some instances of these are in text that is eval'ed. I'm
pretty sure that things could go wrong during the eval too, but that's
not something shellcheck can check.
gdb/ChangeLog:
* gdbarch.sh: Use double quotes around variables.
Fix all instances of this:
In gdbarch.sh line 2182:
printf " gdb_assert (!(${invalid_p}));\n"
^-- SC2059: Don't use variables in the printf format string. Use printf "..%s.." "$foo".
... by doing exactly as the message suggests.
The rationale explained here [1] makes sense, if there happens to be a
format specifier in text substituted for the variable, the printf won't
do what we expect.
[1] https://github.com/koalaman/shellcheck/wiki/SC2059
gdb/ChangeLog:
* gdbarch.sh: Use %s with printf, instead of variables in the
format string.
I think it makes sense to have it there instead of in the catch-all
defs.h.
gdb/ChangeLog:
* defs.h (enum gdb_osabi): Move to...
* osabi.h (enum gdb_osabi): ... here.
* gdbarch.sh: Include osabi.h in gdbarch.h.
* gdbarch.h: Re-generate.
To help with readability, add the type displaced_step_closure_up, an
alias for std::unique_ptr<displaced_step_closure>, and use it throughout
the code base.
gdb/ChangeLog:
* aarch64-tdep.c (aarch64_displaced_step_copy_insn): Use
displaced_step_closure_up.
* aarch64-tdep.h (aarch64_displaced_step_copy_insn): Likewise.
(struct displaced_step_closure_up):
* amd64-tdep.c (amd64_displaced_step_copy_insn): Likewise.
* amd64-tdep.h (amd64_displaced_step_copy_insn): Likewise.
* arm-linux-tdep.c (arm_linux_displaced_step_copy_insn):
Likewise.
* gdbarch.sh (displaced_step_copy_insn): Likewise.
* gdbarch.c, gdbarch.h: Re-generate.
* i386-linux-tdep.c (i386_linux_displaced_step_copy_insn): Use
displaced_step_closure_up.
* i386-tdep.c (i386_displaced_step_copy_insn): Likewise.
* i386-tdep.h (i386_displaced_step_copy_insn): Likewise.
* infrun.h (displaced_step_closure_up): New type alias.
(struct displaced_step_inferior_state) <step_closure>: Change
type to displaced_step_closure_up.
* rs6000-tdep.c (ppc_displaced_step_copy_insn): Use
displaced_step_closure_up.
* s390-tdep.c (s390_displaced_step_copy_insn): Likewise.
This callback dynamically allocates a specialized displaced_step_closure, and
gives the ownership of the object to its caller. So I think it would make
sense for the callback to return an std::unique_ptr, this is what this patch
implements.
gdb/ChangeLog:
* gdbarch.sh (displaced_step_copy_insn): Change return type to an
std::unique_ptr.
* gdbarch.c: Re-generate.
* gdbarch.h: Re-generate.
* infrun.c (displaced_step_prepare_throw): Adjust to std::unique_ptr
change.
* aarch64-tdep.c (aarch64_displaced_step_copy_insn): Change return
type to std::unique_ptr.
* aarch64-tdep.h (aarch64_displaced_step_copy_insn): Likewise.
* amd64-tdep.c (amd64_displaced_step_copy_insn): Likewise.
* amd64-tdep.h (amd64_displaced_step_copy_insn): Likewise.
* arm-linux-tdep.c (arm_linux_displaced_step_copy_insn): Likewise.
* i386-linux-tdep.c (i386_linux_displaced_step_copy_insn): Likewise.
* i386-tdep.c (i386_displaced_step_copy_insn): Likewise.
* i386-tdep.h (i386_displaced_step_copy_insn): Likewise.
* rs6000-tdep.c (ppc_displaced_step_copy_insn): Likewise.
* s390-tdep.c (s390_displaced_step_copy_insn): Likewise.
New in v3:
- Code cleanups based on reviews.
New in v2:
- Fixed misc problems based on reviews.
- Switched to using gdbarch_program_breakpoint_here_p as opposed to
gdbarch_insn_is_breakpoint.
- Fixed matching of brk instructions. Previously the mask was incorrect, which
was showing up as a few failures in the testsuite. Now it is clean.
- New testcase (separate patch).
- Moved program_breakpoint_here () to arch-utils.c and made it the default
implementation of gdbarch_program_breakpoint_here_p.
--
It was reported to me that program breakpoints (permanent ones inserted into
the code itself) other than the one GDB uses for AArch64 (0xd4200000) do not
generate visible stops when continuing, and GDB will continue spinning
infinitely.
This happens because GDB, upon hitting one of those program breakpoints, thinks
the SIGTRAP came from a delayed breakpoint hit...
(gdb) x/i $pc
=> 0x4005c0 <problem_function>: brk #0x90f
(gdb) c
Continuing.
infrun: clear_proceed_status_thread (process 14198)
infrun: proceed (addr=0xffffffffffffffff, signal=GDB_SIGNAL_DEFAULT)
infrun: proceed: resuming process 14198
infrun: resume (step=0, signal=GDB_SIGNAL_0), trap_expected=0, current thread [process 14198] at 0x4005c0
infrun: infrun_async(1)
infrun: prepare_to_wait
infrun: target_wait (-1.0.0, status) =
infrun: 14198.14198.0 [process 14198],
infrun: status->kind = stopped, signal = GDB_SIGNAL_TRAP
infrun: handle_inferior_event status->kind = stopped, signal = GDB_SIGNAL_TRAP
infrun: stop_pc = 0x4005c0
infrun: delayed software breakpoint trap, ignoring
infrun: no stepping, continue
infrun: resume (step=0, signal=GDB_SIGNAL_0), trap_expected=0, current thread [process 14198] at 0x4005c0
infrun: prepare_to_wait
infrun: target_wait (-1.0.0, status) =
infrun: 14198.14198.0 [process 14198],
infrun: status->kind = stopped, signal = GDB_SIGNAL_TRAP
infrun: handle_inferior_event status->kind = stopped, signal = GDB_SIGNAL_TRAP
infrun: stop_pc = 0x4005c0
infrun: delayed software breakpoint trap, ignoring
infrun: no stepping, continue
infrun: resume (step=0, signal=GDB_SIGNAL_0), trap_expected=0, current thread [process 14198] at 0x4005c0
infrun: prepare_to_wait
infrun: target_wait (-1.0.0, status) =
infrun: 14198.14198.0 [process 14198],
infrun: status->kind = stopped, signal = GDB_SIGNAL_TRAP
infrun: handle_inferior_event status->kind = stopped, signal = GDB_SIGNAL_TRAP
infrun: stop_pc = 0x4005c0
infrun: delayed software breakpoint trap, ignoring
infrun: no stepping, continue
infrun: resume (step=0, signal=GDB_SIGNAL_0), trap_expected=0, current thread [process 14198] at 0x4005c0
infrun: prepare_to_wait
infrun: target_wait (-1.0.0, status) =
infrun: 14198.14198.0 [process 14198],
infrun: status->kind = stopped, signal = GDB_SIGNAL_TRAP
infrun: handle_inferior_event status->kind = stopped, signal = GDB_SIGNAL_TRAP
infrun: stop_pc = 0x4005c0
infrun: delayed software breakpoint trap, ignoring
infrun: no stepping, continue
infrun: resume (step=0, signal=GDB_SIGNAL_0), trap_expected=0, current thread [process 14198] at 0x4005c0
infrun: prepare_to_wait
infrun: target_wait (-1.0.0, status) =
infrun: 14198.14198.0 [process 14198],
infrun: status->kind = stopped, signal = GDB_SIGNAL_TRAP
...
... which is not the case.
If the program breakpoint is one GDB recognizes, then it will stop when it
hits it.
(gdb) x/i $pc
=> 0x4005c0 <problem_function>: brk #0x0
(gdb) c
Continuing.
infrun: clear_proceed_status_thread (process 14193)
infrun: proceed (addr=0xffffffffffffffff, signal=GDB_SIGNAL_DEFAULT)
infrun: proceed: resuming process 14193
infrun: resume (step=0, signal=GDB_SIGNAL_0), trap_expected=0, current thread [process 14193] at 0x4005c0
infrun: infrun_async(1)
infrun: prepare_to_wait
infrun: target_wait (-1.0.0, status) =
infrun: 14193.14193.0 [process 14193],
infrun: status->kind = stopped, signal = GDB_SIGNAL_TRAP
infrun: handle_inferior_event status->kind = stopped, signal = GDB_SIGNAL_TRAP
infrun: stop_pc = 0x4005c0
infrun: random signal (GDB_SIGNAL_TRAP)
infrun: stop_waiting
infrun: stop_all_threads
infrun: stop_all_threads, pass=0, iterations=0
infrun: process 14193 not executing
infrun: stop_all_threads, pass=1, iterations=1
infrun: process 14193 not executing
infrun: stop_all_threads done
Program received signal SIGTRAP, Trace/breakpoint trap.
problem_function () at brk_0.c:7
7 asm("brk %0\n\t" ::"n"(0x0));
infrun: infrun_async(0)
Otherwise GDB will keep trying to resume the inferior and will keep
seeing the SIGTRAP's, without stopping.
To the user it appears GDB has gone into an infinite loop, interruptible only
by Ctrl-C.
Also, windbg seems to use a different variation of AArch64 breakpoint compared
to GDB. This causes problems when debugging Windows on ARM binaries, when
program breakpoints are being used.
The proposed patch creates a new gdbarch method (gdbarch_program_breakpoint_here_p)
that tells GDB whether the underlying instruction is a breakpoint instruction
or not.
This is more general than only checking for the instruction GDB uses as
breakpoint.
The existing logic is still preserved for targets that do not implement this
new gdbarch method.
The end result is like so:
(gdb) x/i $pc
=> 0x4005c0 <problem_function>: brk #0x90f
(gdb) c
Continuing.
infrun: clear_proceed_status_thread (process 16417)
infrun: proceed (addr=0xffffffffffffffff, signal=GDB_SIGNAL_DEFAULT)
infrun: proceed: resuming process 16417
infrun: resume (step=0, signal=GDB_SIGNAL_0), trap_expected=0, current thread [process 16417] at 0x4005c0
infrun: infrun_async(1)
infrun: prepare_to_wait
infrun: target_wait (-1.0.0, status) =
infrun: 16417.16417.0 [process 16417],
infrun: status->kind = stopped, signal = GDB_SIGNAL_TRAP
infrun: handle_inferior_event status->kind = stopped, signal = GDB_SIGNAL_TRAP
infrun: stop_pc = 0x4005c0
infrun: random signal (GDB_SIGNAL_TRAP)
infrun: stop_waiting
infrun: stop_all_threads
infrun: stop_all_threads, pass=0, iterations=0
infrun: process 16417 not executing
infrun: stop_all_threads, pass=1, iterations=1
infrun: process 16417 not executing
infrun: stop_all_threads done
Program received signal SIGTRAP, Trace/breakpoint trap.
problem_function () at brk.c:7
7 asm("brk %0\n\t" ::"n"(0x900 + 0xf));
infrun: infrun_async(0)
gdb/ChangeLog:
2020-01-29 Luis Machado <luis.machado@linaro.org>
* aarch64-tdep.c (BRK_INSN_MASK): Define to 0xffe0001f.
(BRK_INSN_MASK): Define to 0xd4200000.
(aarch64_program_breakpoint_here_p): New function.
(aarch64_gdbarch_init): Set gdbarch_program_breakpoint_here_p hook.
* arch-utils.c (default_program_breakpoint_here_p): Moved from
breakpoint.c.
* arch-utils.h (default_program_breakpoint_here_p): Moved from
breakpoint.h
* breakpoint.c (bp_loc_is_permanent): Changed return type to bool and
call gdbarch_program_breakpoint_here_p.
(program_breakpoint_here): Moved to arch-utils.c, renamed to
default_program_breakpoint_here_p, changed return type to bool and
simplified.
* breakpoint.h (program_breakpoint_here): Moved prototype to
arch-utils.h, renamed to default_program_breakpoint_here_p and changed
return type to bool.
* gdbarch.c: Regenerate.
* gdbarch.h: Regenerate.
* gdbarch.sh (program_breakpoint_here_p): New method.
* infrun.c (handle_signal_stop): Call
gdbarch_program_breakpoint_here_p.
In commit
gdb: add back declarations for _initialize functions
6c2659886f7018fcca26ee0fc813bc9748fb8513
I wrongfully edited gdbarch.c, instead of editing gdbarch.sh and
re-generating gdbarch.c. This patch fixes gdbarch.sh to add a
declaration for _initialize_gdbarch. gdbarch.c is not changed, as the
output of gdbarch.sh now matches the current state of gdbarch.c.
gdb/ChangeLog:
* gdbarch.sh: Add declaration for _initialize_gdbarch.
These are files that need to be updated by hand, because the copyright.py
script isn't able to handle them automatically.
gdb/ChangeLog:
* gdbarch.sh: Update copyright year range of generated files.
gdb/doc/ChangeLog:
* gdb.texinfo, refcard.tex: Update copyright year range.
From what I can tell, set_gdbarch_bits_big_endian has never been used.
That is, all architectures since its introduction have simply used the
default, which is simply check the architecture's byte-endianness.
Because this interferes with the scalar_storage_order code, this patch
removes this gdbarch setting entirely. In some places,
type_byte_order is used rather than the plain gdbarch.
gdb/ChangeLog
2019-12-04 Tom Tromey <tromey@adacore.com>
* ada-lang.c (decode_constrained_packed_array)
(ada_value_assign, value_assign_to_component): Update.
* dwarf2loc.c (rw_pieced_value, access_memory)
(dwarf2_compile_expr_to_ax): Update.
* dwarf2read.c (dwarf2_add_field): Update.
* eval.c (evaluate_subexp_standard): Update.
* gdbarch.c, gdbarch.h: Rebuild.
* gdbarch.sh (bits_big_endian): Remove.
* gdbtypes.h (union field_location): Update comment.
* target-descriptions.c (make_gdb_type): Update.
* valarith.c (value_bit_index): Update.
* value.c (struct value) <bitpos>: Update comment.
(unpack_bits_as_long, modify_field): Update.
* value.h (value_bitpos): Update comment.
Change-Id: I379b5e0c408ec8742f7a6c6b721108e73ed1b018
This patch was inspired by a recent review that recommended using
std::string in a new implementation of the gcc_target_options gdbarch
function. It changes this function to return std::string rather than
an ordinary xmalloc'd string.
I believe this caught a latent memory leak in compile.c:get_args.
Tested on x86-64 Fedora 29.
gdb/ChangeLog
2019-10-15 Tom Tromey <tromey@adacore.com>
* gdbarch.h, gdbarch.c: Rebuild.
* gdbarch.sh (gcc_target_options): Change return type to
std::string.
* compile/compile.c (get_args): Update.
* nios2-tdep.c (nios2_gcc_target_options): Return std::string.
* arm-linux-tdep.c (arm_linux_gcc_target_options): Return
std::string.
* aarch64-linux-tdep.c (aarch64_linux_gcc_target_options): Return
std::string.
* arch-utils.c (default_gcc_target_options): Return std::string.
* arch-utils.h (default_gcc_target_options): Return std::string.
* s390-tdep.c (s390_gcc_target_options): Return std::string.
Change-Id: I51f61703426a323089e646da8f22320a2cafbc1f
Add a new print_pc which prints both the PC and a new field addr_flags.
Call this wherever the PC is printed in stack.c.
Add a new gdbarch method get_pc_address_flags to obtain the addr_flag
contents. By default returns an empty string, on AArch64 this returns
PAC if the address has been masked in the frame.
Document this in the manual and NEWS file.
gdb/ChangeLog:
* NEWS (Other MI changes): New subsection.
* aarch64-tdep.c (aarch64_get_pc_address_flags): New function.
(aarch64_gdbarch_init): Add aarch64_get_pc_address_flags.
* arch-utils.c (default_get_pc_address_flags): New function.
* arch-utils.h (default_get_pc_address_flags): New declaration.
* gdbarch.sh: Add get_pc_address_flags.
* gdbarch.c: Regenerate.
* gdbarch.h: Likewise.
* stack.c (print_pc): New function.
(print_frame_info) (print_frame): Call print_pc.
gdb/doc/ChangeLog:
* gdb.texinfo (AArch64 Pointer Authentication)
(GDB/MI Breakpoint Information) (Frame Information): Document
addr_field.
Non-const reference parameter should be avoided according to the GDB
coding standard:
https://sourceware.org/gdb/wiki/Internals%20GDB-C-Coding-Standards#Avoid_non-const_reference_parameters.2C_use_pointers_instead
This commit updates the gdbarch method gdbarch_stap_adjust_register,
and the one implementation i386_stap_adjust_register to avoid using a
non-const reference parameter.
I've also removed the kfail from the testsuite for bug 24541, as this
issue is now resolved.
gdb/ChangeLog:
PR breakpoints/24541
* gdbarch.c: Regenerate.
* gdbarch.h: Regenerate.
* gdbarch.sh: Adjust return type and parameter types for
'stap_adjust_register'.
(i386_stap_adjust_register): Adjust signature and return new
register name.
* stap-probe.c (stap_parse_register_operand): Adjust use of
'gdbarch_stap_adjust_register'.
gdb/testsuite/ChangeLog:
PR breakpoints/24541
* gdb.mi/mi-catch-cpp-exceptions.exp: Remove kfail due to 24541.
This bug has been reported on PR breakpoints/24541, but it is possible
to reproduce it easily by running:
make check-gdb TESTS=gdb.base/stap-probe.exp RUNTESTFLAGS='--target_board unix/-m32'
The underlying cause is kind of complex, and involves decisions made
by GCC and the sys/sdt.h header file about how to represent a probe
argument that lives in a register in 32-bit programs. I'll use
Andrew's example on the bug to illustrate the problem.
libstdc++ has a probe named "throw" with two arguments. On i386, the
probe is:
stapsdt 0x00000028 NT_STAPSDT (SystemTap probe descriptors)
Provider: libstdcxx
Name: throw
Location: 0x00072c96, Base: 0x00133d64, Semaphore: 0x00000000
Arguments: 4@%si 4@%di
I.e., the first argument is an unsigned 32-bit value (represented by
the "4@") that lives on %si, and the second argument is an unsigned
32-bit value that lives on %di. Note the discrepancy between the
argument size reported by the probe (32-bit) and the register size
being used to store the value (16-bit).
However, if you take a look at the disassemble of a program that uses
this probe, you will see:
00072c80 <__cxa_throw@@CXXABI_1.3>:
72c80: 57 push %edi
72c81: 56 push %esi
72c82: 53 push %ebx
72c83: 8b 74 24 10 mov 0x10(%esp),%esi
72c87: e8 74 bf ff ff call 6ec00 <__cxa_finalize@plt+0x980>
72c8c: 81 c3 74 e3 10 00 add $0x10e374,%ebx
72c92: 8b 7c 24 14 mov 0x14(%esp),%edi
72c96: 90 nop <----------------- PROBE IS HERE
72c97: e8 d4 a2 ff ff call 6cf70 <__cxa_get_globals@plt>
72c9c: 83 40 04 01 addl $0x1,0x4(%eax)
72ca0: 83 ec 04 sub $0x4,%esp
72ca3: ff 74 24 1c pushl 0x1c(%esp)
72ca7: 57 push %edi
72ca8: 56 push %esi
72ca9: e8 62 a3 ff ff call 6d010 <__cxa_init_primary_exception@plt>
72cae: 8d 70 40 lea 0x40(%eax),%esi
72cb1: c7 00 01 00 00 00 movl $0x1,(%eax)
72cb7: 89 34 24 mov %esi,(%esp)
72cba: e8 61 96 ff ff call 6c320 <_Unwind_RaiseException@plt>
72cbf: 89 34 24 mov %esi,(%esp)
72cc2: e8 c9 84 ff ff call 6b190 <__cxa_begin_catch@plt>
72cc7: e8 d4 b3 ff ff call 6e0a0 <_ZSt9terminatev@plt>
72ccc: 66 90 xchg %ax,%ax
72cce: 66 90 xchg %ax,%ax
Note how the program is actually using %edi, and not %di, to store the
second argument. This is the problem here.
GDB will basically read the probe argument, then read the contents of
%di, and then cast this value to uint32_t, which causes the wrong
value to be obtained. In the gdb.base/stap-probe.exp case, this makes
GDB read the wrong memory location, and not be able to display a test
string. In Andrew's example, this causes GDB to actually stop at a
"catch throw" when it should actually have *not* stopped.
After some discussion with Frank Eigler and Jakub Jelinek, it was
decided that this bug should be fixed on the client side (i.e., the
program that actually reads the probes), and this is why I'm proposing
this patch.
The idea is simple: we will have a gdbarch method, which, for now, is
only used by i386. The generic code that deals with register operands
on gdb/stap-probe.c will call this method if it exists, passing the
current parse information, the register name and its number.
The i386 method will then verify if the register size is greater or
equal than the size reported by the stap probe (the "4@" part). If it
is, we're fine. Otherwise, it will check if we're dealing with any of
the "extendable" registers (like ax, bx, si, di, sp, etc.). If we
are, it will change the register name to include the "e" prefix.
I have tested the patch here in many scenarios, and it fixes Andrew's
bug and also the regressions I mentioned before, on
gdb.base/stap-probe.exp. No regressions where found on other tests.
Comments?
gdb/ChangeLog:
2019-06-27 Sergio Durigan Junior <sergiodj@redhat.com>
PR breakpoints/24541
* gdbarch.c: Regenerate.
* gdbarch.h: Regenerate.
* gdbarch.sh: Add 'stap_adjust_register'.
* i386-tdep.c: Include '<unordered_set>'.
(i386_stap_adjust_register): New function.
(i386_elf_init_abi): Register 'i386_stap_adjust_register'.
* stap-probe.c (stap_parse_register_operand): Call
'gdbarch_stap_adjust_register'.
This makes a new base class, expr_builder, for parser_state. This
separates the state needed to construct an expression from the state
needed by the parsers.
gdb/ChangeLog
2019-04-04 Tom Tromey <tom@tromey.com>
* gdbarch.h, gdbarch.c: Rebuild.
* gdbarch.sh (dtrace_parse_probe_argument): Change type.
* stap-probe.h:
(struct stap_parse_info): Replace "parser_state" with
"expr_builder".
* parser-defs.h (struct expr_builder): Rename from "parser_state".
(parser_state): New class.
* parse.c (expr_builder): Rename.
(expr_builder::release): Rename.
(write_exp_elt, write_exp_elt_opcode, write_exp_elt_sym)
(write_exp_elt_msym, write_exp_elt_block, write_exp_elt_objfile)
(write_exp_elt_longcst, write_exp_elt_floatcst)
(write_exp_elt_type, write_exp_elt_intern, write_exp_string)
(write_exp_string_vector, write_exp_bitstring)
(write_exp_msymbol, mark_struct_expression)
(write_dollar_variable)
(insert_type_address_space, increase_expout_size): Replace
"parser_state" with "expr_builder".
* dtrace-probe.c: Replace "parser_state" with "expr_builder".
* amd64-linux-tdep.c (amd64_dtrace_parse_probe_argument): Replace
"parser_state" with "expr_builder".
Simon Marchi
Luis Machado
Tom Tromey
Joel Brobecker
Simon Marchi
Pedro Alves
Felix Willgerodt
Kevin Buettner
John Baldwin
Andrew Burgess
Rainer Orth
Tom Tromey
Alan Hayward
Sergio Durigan Junior