Remove regcache_raw_write, update all callers to use regcache::raw_write
instead.
gdb/ChangeLog:
* regcache.h (regcache_raw_write): Remove, update callers to use
regcache::raw_write instead.
* regcache.c (regcache_raw_write): Remove.
Remove regcache_raw_read, update all callers to use
readable_regcache::raw_read instead.
gdb/ChangeLog:
* regcache.h (regcache_raw_read): Remove, update callers to use
readable_regcache::raw_read instead.
* regcache.c (regcache_raw_read): Remove.
Now, m_readonly_p is always false, so we can remove it, and regcache no
longer includes pseudo registers. Some regcache methods are lift up to
its parent class, like reg_buffer or detached_regcache.
gdb:
2018-02-21 Yao Qi <yao.qi@linaro.org>
* regcache.c (regcache::regcache): Update.
(regcache::invalidate): Move it to detached_regcache::invalidate.
(get_thread_arch_aspace_regcache): Update.
(regcache::raw_update): Update.
(regcache::cooked_read): Remove some code.
(regcache::cooked_read_value): Likewise.
(regcache::raw_write): Remove assert on m_readonly_p.
(regcache::raw_supply_integer): Move it to
detached_regcache::raw_supply_integer.
(regcache::raw_supply_zeroed): Likewise.
* regcache.h (detached_regcache) <raw_supply_integer>: New
declaration.
<raw_supply_zeroed, invalidate>: Likewise.
(regcache) <raw_supply_integer, raw_supply_zeroed>: Removed.
<invalidate>: Likewise.
<m_readonly_p>: Removed.
Nowadays, we create a readonly regcache in get_return_value, and pass it
to gdbarch_return_value to get the return value. In theory, we can pass a
readable_regcache instance and get the return value, because we don't need
to modify the regcache. Unfortunately, gdbarch_return_value is designed
to multiplex regcache, according to READBUF and WRITEBUF.
# If READBUF is not NULL, extract the return value and save it in this
# buffer.
#
# If WRITEBUF is not NULL, it contains a return value which will be
# stored into the appropriate register.
In fact, gdbarch_return_value should be split to three functions, 1) only
return return_value_convention, 2) pass regcache_readonly and readbuf, 3)
pass regcache and writebuf. These changes are out of the scope of this
patch series, so I pass regcache to gdbarch_return_value even for read,
and trust each gdbarch backend doesn't modify regcache.
gdb:
2018-02-21 Yao Qi <yao.qi@linaro.org>
* infcmd.c (get_return_value): Let stop_regs point to
get_current_regcache.
* regcache.c (regcache::regcache): Remove.
(register_dump_reg_buffer): New class.
(regcache_print): Adjust.
* regcache.h (regcache): Remove constructors.
Nowadays, we need to dump registers contents from "readwrite" regcache and
"readonly" regcache,
if (target_has_registers)
get_current_regcache ()->dump (out, what_to_dump);
else
{
/* For the benefit of "maint print registers" & co when
debugging an executable, allow dumping a regcache even when
there is no thread selected / no registers. */
regcache dummy_regs (target_gdbarch ());
dummy_regs.dump (out, what_to_dump);
}
since we'll have two different types/classes for "readwrite" regcache and
"readonly" regcache, we have to move dump method to their parent class,
reg_buffer. However, the functionality of "dump" looks unnecessary to
reg_buffer (because some dump modes like regcache_dump_none,
regcache_dump_remote and regcache_dump_groups don't need reg_buffer at
all, they need gdbarch to do the dump), so I decide to move "dump" into a
separate classes, and each sub-class is about each mode of dump.
gdb:
2018-02-21 Yao Qi <yao.qi@linaro.org>
* regcache.c (class register_dump): New class.
(register_dump_regcache, register_dump_none): New class.
(register_dump_remote, register_dump_groups): New class.
(regcache_print): Update.
* regcache.h (regcache_dump_what): Move it to regcache.c.
(regcache) <dump>: Remove.
jit.c uses the regcache in a slightly different way, the regcache dosen't
write through to target, but it has read and write methods. If I apply
regcache in record-full.c, it has the similar use pattern. This patch
adds a new class detached_regcache, a register buffer, but can be
read and written.
Since jit.c doesn't want to write registers through to target, it uses
regcache as a readonly regcache (because only readonly regcache
disconnects from the target), but it adds a hole in regcache
(raw_set_cached_value) in order to modify a readonly regcache. This patch
fixes this hole completely.
regcache inherits detached_regcache, and detached_regcache inherits
readable_regcache. The ideal design is that both detached_regcache and
readable_regcache inherit reg_buffer, and regcache inherit
detached_regcache and regcache_read (virtual inheritance). I concern
about the performance overhead of virtual inheritance, so I don't do it in
the patch.
gdb:
2018-02-21 Yao Qi <yao.qi@linaro.org>
* jit.c (struct jit_unwind_private) <regcache>: Change its type to
reg_buffer_rw *.
(jit_unwind_reg_set_impl): Call raw_supply.
(jit_frame_sniffer): Use reg_buffer_rw.
* record-full.c (record_full_core_regbuf): Change its type.
(record_full_core_open_1): Use reg_buffer_rw.
(record_full_close): Likewise.
(record_full_core_fetch_registers): Use regcache->raw_supply.
(record_full_core_store_registers): Likewise.
* regcache.c (regcache::get_register_status): Move it to
reg_buffer.
(regcache_raw_set_cached_value): Remove.
(regcache::raw_set_cached_value): Remove.
(regcache::raw_write): Call raw_supply.
(regcache::raw_supply): Move it to reg_buffer_rw.
* regcache.h (regcache_raw_set_cached_value): Remove.
(reg_buffer_rw): New class.
This patch adds a new class (type) for readonly regcache, which is
created via regcache::save. readonly_detached_regcache inherits
readable_regcache.
gdb:
2018-02-21 Yao Qi <yao.qi@linaro.org>
* dummy-frame.c (dummy_frame_cache) <prev_regcache>: Use
readonly_detached_regcache.
(dummy_frame_prev_register): Use regcache->cooked_read.
* frame.c (frame_save_as_regcache): Change return type.
(frame_pop): Update.
* frame.h (frame_save_as_regcache): Update declaration.
* inferior.h (get_infcall_suspend_state_regcache): Update
declaration.
* infrun.c (infcall_suspend_state) <registers>: use
readonly_detached_regcache.
(save_infcall_suspend_state): Don't use regcache_dup.
(get_infcall_suspend_state_regcache): Change return type.
* linux-fork.c (struct fork_info) <savedregs>: Change to
readonly_detached_regcache.
<pc>: New field.
(fork_save_infrun_state): Don't use regcache_dup.
(info_checkpoints_command): Adjust.
* mi/mi-main.c (register_changed_p): Update declaration.
(mi_cmd_data_list_changed_registers): Use
readonly_detached_regcache.
(register_changed_p): Change parameter type to
readonly_detached_regcache.
* ppc-linux-tdep.c (ppu2spu_cache) <regcache>: Use
readonly_detached_regcache.
(ppu2spu_sniffer): Construct a new readonly_detached_regcache.
* regcache.c (readonly_detached_regcache::readonly_detached_regcache):
New.
(regcache::save): Move it to reg_buffer.
(regcache::restore): Change parameter type.
(regcache_dup): Remove.
* regcache.h (reg_buffer) <save>: New method.
(readonly_detached_regcache): New class.
* spu-tdep.c (spu2ppu_cache) <regcache>: Use
readonly_detached_regcache.
(spu2ppu_sniffer): Construct a new readonly_detached_regcache.
... instead we start to use regcache methods save and restore. It is
quite straightforward to replace regcache_save with regcache->save.
regcache_cpy has some asserts, some of them not necessary, like
gdb_assert (src != dst);
because we already assert !m_readonly_p and src->m_readonly_p, so
src isn't dst. Some of the asserts are moved to ::restore.
gdb:
2018-02-21 Yao Qi <yao.qi@linaro.org>
* frame.c (frame_save_as_regcache): Use regcache method save.
(frame_pop): Use regcache method restore.
* infrun.c (restore_infcall_suspend_state): Likewise.
* linux-fork.c (fork_load_infrun_state): Likewise.
* ppc-linux-tdep.c (ppu2spu_sniffer): User regcache method
save.
* regcache.c (regcache_save): Remove.
(regcache::restore): More asserts.
(regcache_cpy): Remove.
* regcache.h (regcache_save): Remove the declaration.
(regcache::restore): Move from private to public.
Remove the friend declaration of regcache_cpy.
(regcache_cpy): Remove declaration.
pseudo registers are either from raw registers or memory, so
gdbarch methods pseudo_register_read and pseudo_register_read_value
should have regcache object which only have read methods. In other
words, we should disallow writing to regcache in these two gdbarch
methods. In order to apply this restriction, this patch adds a new
class readable_regcache, derived from reg_buffer, and it only has
raw_read and cooked_read methods. regcache is derived from
readable_regcache. This patch also passes readable_regcache instead of
regcache to gdbarch methods pseudo_register_read and
pseudo_register_read_value.
This patch moves raw_read* and cooked_read* methods to readable_regcache,
which is straightforward. One thing not straightforward is that I split
regcache::xfer_part to readable_regcache::read_part and regcache::write_part,
because readable_regcache can only have methods to read.
readable_regcache is an abstract base class, and it has a pure virtual
function raw_update, because I don't want readable_regcache know where
these raw registers are from. They can be from either the target
(readwrite regcache) or the regcache itself (readonly regcache).
gdb:
2018-02-21 Yao Qi <yao.qi@linaro.org>
* aarch64-tdep.c (aarch64_pseudo_register_read_value): Change
parameter type to 'readable_regcache *'.
* amd64-tdep.c (amd64_pseudo_register_read_value): Likewise.
* arm-tdep.c (arm_neon_quad_read): Likewise.
(arm_pseudo_read): Likewise.
* avr-tdep.c (avr_pseudo_register_read): Likewise.
* bfin-tdep.c (bfin_pseudo_register_read): Likewise.
* frv-tdep.c (frv_pseudo_register_read): Likewise.
* gdbarch.c: Re-generated.
* gdbarch.h: Re-generated.
* gdbarch.sh (pseudo_register_read): Change parameter type to
'readable_regcache *'.
(pseudo_register_read_value): Likewise.
* h8300-tdep.c (pseudo_from_raw_register): Likewise.
(h8300_pseudo_register_read): Likewise.
* hppa-tdep.c (hppa_pseudo_register_read): Likewise.
* i386-tdep.c (i386_mmx_regnum_to_fp_regnum): Likewise.
(i386_pseudo_register_read_into_value): Likewise.
(i386_pseudo_register_read_value): Likewise.
* i386-tdep.h (i386_pseudo_register_read_into_value): Update
declaration.
* ia64-tdep.c (ia64_pseudo_register_read): Likewise.
* m32c-tdep.c (m32c_raw_read): Likewise.
(m32c_read_flg): Likewise.
(m32c_banked_register): Likewise.
(m32c_banked_read): Likewise.
(m32c_sb_read): Likewise.
(m32c_part_read): Likewise.
(m32c_cat_read): Likewise.
(m32c_r3r2r1r0_read): Likewise.
(m32c_pseudo_register_read): Likewise.
* m68hc11-tdep.c (m68hc11_pseudo_register_read): Likewise.
* mep-tdep.c (mep_pseudo_cr32_read): Likewise.
(mep_pseudo_cr64_read): Likewise.
(mep_pseudo_register_read): Likewise.
* mips-tdep.c (mips_pseudo_register_read): Likewise.
* msp430-tdep.c (msp430_pseudo_register_read): Likewise.
* nds32-tdep.c (nds32_pseudo_register_read): Likewise.
* regcache.c (regcache::raw_read): Move it to readable_regcache.
(regcache::cooked_read): Likewise.
(regcache::cooked_read_value): Likewise.
(regcache_cooked_read_signed):
(regcache::cooked_read): Likewise.
* regcache.h (readable_regcache): New class.
(regcache): Inherit readable_regcache. Move some methods to
readable_regcache.
* rl78-tdep.c (rl78_pseudo_register_read): Change
parameter type to 'readable_regcache *'.
* rs6000-tdep.c (do_regcache_raw_read): Remove.
(e500_pseudo_register_read): Change parameter type to
'readable_regcache *'.
(dfp_pseudo_register_read): Likewise.
(vsx_pseudo_register_read): Likewise.
(efpr_pseudo_register_read): Likewise.
* s390-tdep.c (s390_pseudo_register_read): Likewise.
* sh-tdep.c (sh_pseudo_register_read): Likewise.
* sh64-tdep.c (pseudo_register_read_portions): Likewise.
(sh64_pseudo_register_read): Likewise.
* sparc-tdep.c (sparc32_pseudo_register_read): Likewise.
* sparc64-tdep.c (sparc64_pseudo_register_read): Likewise.
* spu-tdep.c (spu_pseudo_register_read_spu): Likewise.
(spu_pseudo_register_read): Likewise.
* xtensa-tdep.c (xtensa_register_read_masked): Likewise.
(xtensa_pseudo_register_read): Likewise.
This patch adds a new class reg_buffer, and regcache inherits it. Class
reg_buffer is a very simple class, which has the buffer for register
contents and status only. It doesn't have any methods to set contents and
status, and it is expected that its children classes can inherit it and
add different access methods.
Another reason I keep class reg_buffer so simple is that I think
reg_buffer can be even reused in other classes which need to record the
registers contents and status, like frame cache for example.
gdb:
2018-02-21 Yao Qi <yao.qi@linaro.org>
* regcache.c (regcache::regcache): Call reg_buffer ctor.
(regcache::arch): Move it to reg_buffer::arch.
(regcache::register_buffer): Likewise.
(regcache::assert_regnum): Likewise.
(regcache::num_raw_registers): Likewise.
* regcache.h (reg_buffer): New class.
(regcache): Inherit reg_buffer.
The address space is useless to readonly regcache, so this patch removes
the parameter to construct readonly regcache.
address_space was added in regcache by 6c95b8d, but for read-write
regcache. regcache::aspace is used for various breakpoint/watchpoint
checking, and these regcache are not read-only regcache.
gdb:
2017-11-02 Yao Qi <yao.qi@linaro.org>
* frame.c (do_frame_register_read): Remove aspace.
* jit.c (jit_frame_sniffer): Likwise.
* ppc-linux-tdep.c (ppu2spu_sniffer): Likewise.
* regcache.c (regcache::regcache): Pass nullptr.
(regcache_print): Caller updated.
* regcache.h (regcache::regcache): Remove one constructor
parameter aspace.
struct regcache_descr has fields nr_raw_registers and gdbarch, and
nr_raw_registers can be got via gdbarch_num_regs (gdbarch), so it looks
nr_raw_registers is redundant. This patch removes it and adds a protected
method num_raw_registers.
gdb:
2017-11-02 Yao Qi <yao.qi@linaro.org>
* regcache.c (struct regcache_descr) <nr_raw_registers>: Remove.
(init_regcache_descr): Use gdbarch_num_regs.
(regcache::regcache): Likewise.
(regcache::get_register_status): Likewise.
(regcache::assert_raw_regnum): Likewise.
(regcache::cooked_read): Likewise.
(regcache::cooked_read_value): Likewise.
(regcache::cooked_write): Likewise.
(regcache::dump): Likewise.
(regcache::num_raw_registers): New method.
* regcache.h (class regcache) <num_raw_registers>: New.
class regcache has some methods checking the range of register number,
this patch is to move it in a new method assert_regnum.
gdb:
2017-11-02 Yao Qi <yao.qi@linaro.org>
* regcache.c (regcache::assert_regnum): New method.
(regcache::invalidate): Call assert_regnum.
(regcache::raw_update): Likewise.
(regcache::raw_write): Likewise.
(regcache::raw_read_part): Likewise.
(regcache::raw_write_part): Likewise.
(regcache::raw_supply): Likewise.
(regcache::raw_supply_integer): Likewise.
(regcache::raw_supply_zeroed): Likewise.
(regcache::raw_collect): Likewise.
(regcache::raw_collect_integer): Likewise.
* regcache.h (regcache::assert_regnum): Declare.
Since xfer_part is already a class method, and only
{raw,cooked}_{read,write} are passed to it. We can remove these two
arguments, but add a bool argument is_raw, indicating raw registers or
cooked registers are accessed.
gdb:
2017-10-17 Yao Qi <yao.qi@linaro.org>
* regcache.c (regcache::xfer_part): Remove parameters read and
write, add parameter is_raw. All callers are updated.
A following patch will remove this hack from within regcache's
implementation:
struct regcache *
get_thread_arch_regcache (ptid_t ptid, struct gdbarch *gdbarch)
{
struct address_space *aspace;
/* For the benefit of "maint print registers" & co when debugging an
executable, allow dumping the regcache even when there is no
thread selected (target_thread_address_space internal-errors if
no address space is found). Note that normal user commands will
fail higher up on the call stack due to no
target_has_registers. */
aspace = (ptid_equal (null_ptid, ptid)
? NULL
: target_thread_address_space (ptid));
i.e., it'll no longer be possible to try to build a regcache for
null_ptid. That change alone would regress the gdbarch self tests
though, causing this:
(gdb) maintenance selftest
[...]
Running selftest register_to_value.
src/gdb/inferior.c:309: internal-error: inferior* find_inferior_pid(int): Assertion `pid != 0' failed.
A problem internal to GDB has been detected,
further debugging may prove unreliable.
Quit this debugging session? (y or n) FAIL: gdb.gdb/unittest.exp: maintenance selftest (GDB internal error)
The problem is that the way the mocking environment for those unit
tests is written is a bit fragile: it creates a special purpose
regcache (and sentinel's frame), using whatever is the current
inferior_ptid (usually null_ptid), and assumes get_current_regcache
will find that in the regcache::current_regcache list.
This commit changes the way the mock environment is created. It
eliminates the special regcache and frame and instead creates a fuller
mock environment, with a custom mock target_ops, and then a mock
inferior and thread "running" on that target.
If there's already a running target when you type "maint selftest",
then we error out, instead of pushing a new target on top of the
existing one (and thus killing the debug session). This results in:
(gdb) maint selftest
(...)
Self test failed: arch i386: target already pushed
Self test failed: arch i386:x86-64: target already pushed
Self test failed: arch i386:x64-32: target already pushed
Self test failed: arch i8086: target already pushed
Self test failed: arch i386:intel: target already pushed
Self test failed: arch i386:x86-64:intel: target already pushed
Self test failed: arch i386:x64-32:intel: target already pushed
Self test failed: arch i386:nacl: target already pushed
Self test failed: arch i386:x86-64:nacl: target already pushed
Self test failed: arch i386:x64-32:nacl: target already pushed
Self test failed: self-test failed at /home/pedro/gdb/mygit/src/gdb/selftest-arch.c:86
(...)
Ran 19 unit tests, 1 failed
I think that's OK, because self tests are really meant to be run from
a clean state right after GDB is started. I'm adding that erroring
out just as safe measure just in case someone types "maint selftest"
on the command line while already debugging something (as I've done
it).
(In my multi-target branch, where this patch originated from, we don't
actually need to error out, because there each inferior has its own
target stack).
Also, note that the current code was doing:
current_inferior()->gdbarch = gdbarch;
without taking care to restore the previous gdbarch. This means that
GDB's state was being left inconsistent after running the self tests,
further supporting the point that there's probably not much
expectation that mixing "maint selftests" and regular debugging in the
same GDB invocation really works. This patch fixes that, regardless.
gdb/ChangeLog:
2017-10-04 Pedro Alves <palves@redhat.com>
* frame.c (create_test_frame): Delete.
* frame.h (create_test_frame): Delete.
* gdbarch-selftests.c: Include gdbthread.h and target.h.
(class regcache_test): Delete.
(test_target_has_registers, test_target_has_stack)
(test_target_has_memory, test_target_prepare_to_store)
(test_target_store_registers): New functions.
(test_target_ops): New class.
(register_to_value_test): Error out if there's already a
process_stratum (or higher) target pushed. Create a fuller mock
environment, with mock target_ops, inferior, address space, thread
and inferior_ptid.
* progspace.c (struct address_space): Move to ...
* progspace.h (struct address_space): ... here.
* regcache.h (regcache::~regcache, regcache::raw_write)
[GDB_SELF_TEST]: No longer virtual.
Nowadays, regcache_cpy is used where src is read-only and dst is not
read-only, so the regcache_cpy can be simplified to handle this case only.
As a result, regcache::cpy_no_passthrough, which is about two read-only
regcache copy, is no longer used, remove it as well.
gdb:
2017-07-18 Yao Qi <yao.qi@linaro.org>
* regcache.c (regcache_cpy): Simplify it.
(regcache::cpy_no_passthrough): Remove it.
* regcache.h (cpy_no_passthrough): Remove it.
(regcache_dup, regcache_cpy): Update comments.
This patch converts functions extract_{unsigned,signed}_integer
to a function template extract_integer, which has two instantiations. It
also does the similar changes to store__{unsigned,signed}_integer,
regcache::raw_read_{unsigned,signed}, regcache::raw_write_{unsigned,signed},
regcache::cooked_read_{unsigned,signed},
regcache::cooked_write_{unsigned,signed}.
This patch was posted here
https://sourceware.org/ml/gdb-patches/2017-05/msg00492.html but the
problem was fixed in a different way. However, I think the patch is still
useful to shorten the code.
gdb:
2017-06-16 Alan Hayward <alan.hayward@arm.com>
Pedro Alves <palves@redhat.com>
Yao Qi <yao.qi@linaro.org>
* defs.h (RequireLongest): New.
(extract_integer): Declare function template.
(extract_signed_integer): Remove the declaration, but define it
static inline.
(extract_unsigned_integer): Likewise.
(store_integer): Declare function template.
(store_signed_integer): Remove the declaration, but define it
static inline.
(store_unsigned_integer): Likewise.
* findvar.c (extract_integer): New function template.
(extract_signed_integer): Remove.
(extract_unsigned_integer): Remove.
(extract_integer<LONGEST>, extract_integer<ULONGEST>): Explicit
instantiations.
(store_integer): New function template.
(store_signed_integer): Remove.
(store_unsigned_integer): Remove.
(store_integer): Explicit instantiations.
* regcache.c (regcache_raw_read_signed): Update.
(regcache::raw_read): New function.
(regcache::raw_read_signed): Remove.
(regcache::raw_read_unsigned): Remove.
(regcache_raw_read_unsigned): Update.
(regcache_raw_write_unsigned): Update.
(regcache::raw_write_signed): Remove.
(regcache::raw_write): New function.
(regcache_cooked_read_signed): Update.
(regcache::raw_write_unsigned): Remove.
(regcache::cooked_read_signed): Remove.
(regcache_cooked_read_unsigned): Update.
(regcache::cooked_read_unsigned): Remove.
(regcache_cooked_write_signed): Update.
(regcache_cooked_write_unsigned): Update.
* regcache.h (regcache) <raw_read_signed>: Remove.
<raw_write_signed, raw_read_unsigned, raw_write_unsigned>: Remove.
<raw_read, raw_write>: New.
<cooked_read_signed, cooked_write_signed>: Remove.
<cooked_write_unsigned, cooked_read_unsigned>: Remove.
<cooked_read, cooked_write>: New.
* sh64-tdep.c (sh64_pseudo_register_read): Update.
(sh64_pseudo_register_write): Update.
Use these to replace instances of MAX_REGISTER_SIZE.
* defs.h (copy_integer_to_size): New declaration.
* findvar.c (copy_integer_to_size): New function.
(do_cint_test): New selftest function.
(copy_integer_to_size_test): Likewise.
(_initialize_findvar): Likewise.
* mips-fbsd-tdep.c (mips_fbsd_supply_reg): Use raw_supply_integer.
(mips_fbsd_collect_reg): Use raw_collect_integer.
* mips-linux-tdep.c (supply_32bit_reg): Use raw_supply_integer.
(mips64_fill_gregset): Use raw_collect_integer
(mips64_fill_fpregset): Use raw_supply_integer.
* regcache.c (regcache::raw_supply_integer): New function.
(regcache::raw_collect_integer): Likewise.
* regcache.h: (regcache::raw_supply_integer): New declaration.
(regcache::raw_collect_integer): Likewise.
This patch adds one unit test for gdbarch methods register_to_value and
value_to_register. The test pass different combinations of {regnu, type}
to gdbarch_register_to_value and gdbarch_value_to_register. In order
to do the test, add a new function create_new_frame to create a fake
frame. It can be improved after we converted frame_info to class.
In order to isolate regcache (from target_ops operations on writing
registers, like target_store_registers), the sub-class of regcache in the
test override raw_write. Also, in order to get the right regcache from
get_thread_arch_aspace_regcache, the sub-class of regcache inserts itself
to current_regcache.
Suppose I incorrectly modified the size of buffer as below,
@@ -1228,7 +1228,7 @@ ia64_register_to_value (struct frame_info *frame, int regnum,
int *optimizedp, int *unavailablep)
{
struct gdbarch *gdbarch = get_frame_arch (frame);
- gdb_byte in[MAX_REGISTER_SIZE];
+ gdb_byte in[1];
/* Convert to TYPE. */
if (!get_frame_register_bytes (frame, regnum, 0,
build GDB with "-fsanitize=address" and run unittest.exp, asan can detect
such error
==2302==ERROR: AddressSanitizer: stack-buffer-overflow on address 0x7fff98193870 at pc 0xbd55ea bp 0x7fff981935a0 sp 0x7fff98193598
WRITE of size 16 at 0x7fff98193870 thread T0
#0 0xbd55e9 in frame_register_unwind(frame_info*, int, int*, int*, lval_type*, unsigned long*, int*, unsigned char*) /home/yao/SourceCode/gnu/gdb/git/gdb/frame.c:1119
#1 0xbd58c8 in frame_register(frame_info*, int, int*, int*, lval_type*, unsigned long*, int*, unsigned char*) /home/yao/SourceCode/gnu/gdb/git/gdb/frame.c:1147
#2 0xbd6e25 in get_frame_register_bytes(frame_info*, int, unsigned long, int, unsigned char*, int*, int*) /home/yao/SourceCode/gnu/gdb/git/gdb/frame.c:1427
#3 0x70080a in ia64_register_to_value /home/yao/SourceCode/gnu/gdb/git/gdb/ia64-tdep.c:1236
#4 0xbf570e in gdbarch_register_to_value(gdbarch*, frame_info*, int, type*, unsigned char*, int*, int*) /home/yao/SourceCode/gnu/gdb/git/gdb/gdbarch.c:2619
#5 0xc05975 in register_to_value_test /home/yao/SourceCode/gnu/gdb/git/gdb/gdbarch-selftests.c:131
Or, even if GDB is not built with asan, GDB just crashes.
*** stack smashing detected ***: ./gdb terminated
Aborted (core dumped)
gdb:
2017-05-24 Yao Qi <yao.qi@linaro.org>
* Makefile.in (SFILES): Add gdbarch-selftests.c.
(COMMON_OBS): Add gdbarch-selftests.o.
* frame.c [GDB_SELF_TESTS] (create_new_frame): New function.
* frame.h [GDB_SELF_TESTS] (create_new_frame): Declare.
* gdbarch-selftests.c: New file.
* regcache.h (regcache) <~regcache>: Mark it virtual if
GDB_SELF_TEST.
<raw_write>: Likewise.
This patches moves global variable current_regcache to a class regcache
static variable (protected) so that the unit test I add in the following
patch can access it (by means of extending class regcache in unit test).
gdb:
2017-05-24 Yao Qi <yao.qi@linaro.org>
* regcache.c (current_regcache): Change it to
regcache::current_regcache.
(regcache_observer_target_changed): Update.
(regcache_thread_ptid_changed): Make it a regcache static
method.
(regcache_thread_ptid_changed): Update.
(class regcache_access): New.
(current_regcache_test): Update.
(_initialize_regcache): Update.
* regcache.h: Include forward_list.
(regcache): Declare regcache_thread_ptid_changed and declare
registers_changed_ptid as friend.
This patch adds a tag dispatch ctor to create read-only regcache from
a write-through regcache, also this patch deletes copy ctor and
assignment operator.
gdb:
2017-04-28 Yao Qi <yao.qi@linaro.org>
Pedro Alves <palves@redhat.com>
* regcache.c (regcache::regcache): New tag dispatch ctor.
(do_cooked_read): Moved above.
(regcache_dup): Use the tag dispatch ctor..
* regcache.h (regcache): Declare ctor, delete copy ctor and
assignment operator, remove friend regcache_dup.
regcache_dup, in fact, is to create a readonly regcache from a
non-readonly regcache. This patch adds an assert that src is not
readonly.
gdb:
2017-04-28 Yao Qi <yao.qi@linaro.org>
* regcache.c (regcache_dup): Assert !src->m_readonly_p and
call method save instead of regcache_cpy.
* regcache.h (struct regcache): Make regcache_dup a friend.
This patch introduces the regcache_get_ptid function, which can be used
to retrieve the ptid a regcache is connected to. It is used in
subsequent patches.
gdb/ChangeLog:
* regcache.h (regcache_get_ptid): New function.
* regcache.c (regcache_get_ptid): New function.
This applies the second part of GDB's End of Year Procedure, which
updates the copyright year range in all of GDB's files.
gdb/ChangeLog:
Update copyright year range in all GDB files.
This patch adds a new regcache api regcache_raw_get_signed.
gdb:
2016-11-22 Yao Qi <yao.qi@linaro.org>
* regcache.c (regcache_raw_get_signed): New function.
* regcache.h (regcache_raw_get_signed): Declare.
The jit-reader.exp test isn't really exercising the jit-reader's
unwinder API at all. This commit address that, and then fixes GDB
problems exposed.
- The custom JIT reader provided for the jit-reader.exp testcase
always rejects the jitted function's frame...
This is because the custom JIT reader in the testcase never ever
sets state->code_begin/end, so the bounds check in
gdb.base/jitreader.c:unwind_frame:
if (this_ip >= state->code_end || this_ip < state->code_begin)
return GDB_FAIL;
tends to fail, unless you're "lucky" (because it references
uninitialized data).
The result is that GDB is always actually using a built-in unwinder
for the jitted function.
- The provided unwinder doesn't do anything that GDB's built-in
unwinder can't do.
IOW, we can't really tell whether the JIT reader's unwinder is
working or not.
I fixed that by making the jitted function mangle its own stack
pointer with a xor, and then teaching the jit unwinder to demangle
it back (another xor). So now "backtrace" with GDB's built-in
unwinder fails while with the jit unwinder, it succeeds.
- GDB crashes after unloading the JIT reader, and flushing frames...
I made the testcase use the "flushregs" command after unloading the
JIT reader, to force the JIT frames to be flushed. However, that
crashes GDB...
When reinit_frame_cache tears down a frame's cache, it calls its
unwinder's dealloc_cache method, which for JIT frames ends up in
jit.c:jit_dealloc_cache. This function calls each of the frame's
gdb_reg_value's "free" pointer:
for (i = 0; i < gdbarch_num_regs (frame_arch); i++)
if (priv_data->registers[i] && priv_data->registers[i]->free)
priv_data->registers[i]->free (priv_data->registers[i]);
and the problem is these gdb_reg_value instances have been returned
by the JIT reader that has been already unloaded, and their "free"
function pointers likely point to functions in the DSO that has
already been unloaded...
A fix for that could be to call reinit_frame_cache in
jit_reader_unload_command _before_ unloading the jit reader DSO so
that the jit reader is given a chance to clean up the gdb_reg_values
before it is unloaded. However, the fix for the point below makes
this unnecessary, because it stops jit.c from keeping around
gdb_reg_values in the first place.
- However, it still makes sense to clear the frame cache when loading
or unloading a JIT unwinder.
This makes testing a JIT unwinder a bit simpler.
- Not only the frame cache actually -- gdb is not unloading the
jit-registered objfiles when the JIT reader is unloaded, and not
loading the already-registered descriptors when a JIT reader is
loaded.
The new test exercises unloading the jit reader, loading it back
again, and then making sure the JIT reader's unwinder works again.
Without the unload/re-load of already-read descriptors, the newly
loaded JIT would have no idea where the new function is, because
it's stored at symbol read time.
- I added a couple "info frame" calls to the test, and that
crashes GDB...
The problem is that jit_frame_prev_register assumes it'll only be
called for raw registers, so when it gets a pseudo register number,
the "priv->registers[reg]" access is really an out-of-bounds access.
To fix that, I made jit_frame_prev_register use
gdbarch_pseudo_register_read_value for reading the pseudo-registers.
However, that works with a regcache and we don't have one. To fix
that, I made the JIT unwinder store a regcache in its cache instead
of an array of gdb_reg_value pointers.
gdb/ChangeLog:
2016-07-01 Pedro Alves <palves@redhat.com>
Tom Tromey <tom@tromey.com>
* jit.c (jit_reader_load_command): Call reinit_frame_cache and
jit_inferior_created_hook.
(jit_reader_unload_command): Call reinit_frame_cache and
jit_inferior_exit_hook.
* jit.c (struct jit_unwind_private) <registers>: Delete field.
<regcache>: New field.
(jit_unwind_reg_set_impl): Set the register's value in the
regcache. Free the passed-in gdb_reg_value.
(jit_dealloc_cache): Adjust to free the regcache.
(jit_frame_sniffer): Allocate a regcache instead of an array of
gdb_reg_value pointers.
(jit_frame_this_id): Adjust.
(jit_frame_prev_register): Read raw registers off of the regcache
instead of from the gdb_reg_value pointer array. Use
gdbarch_pseudo_register_read_value to read pseudo registers.
* regcache.c (regcache_raw_set_cached_value): New function,
factored out from ...
(regcache_raw_write): ... here.
* regcache.h (regcache_raw_set_cached_value): Declare.
gdb/testsuite/ChangeLog:
2016-07-01 Pedro Alves <palves@redhat.com>
* gdb.base/jit-reader.exp (info_registers_current_frame): New
procedure.
(jit_reader_test): Test the jit reader's unwinder.
* gdb.base/jithost.c (jit_function_00_code): New global.
(main): Use memcpy to fill in the mmapped code, instead of poking
bytes manually here.
* gdb.base/jitreader.c (enum register_mapping) <AMD64_RBP>: New
value.
(read_debug_info): Save the function's range.
(read_sp): New function.
(unwind_frame): Use it. Also unwind RBP.
(get_frame_id): Use read_sp.
(gdb_init_reader): Use calloc instead of malloc.
* lib/gdb.exp (get_hexadecimal_valueof): Add optional 'test'
parameter. Use gdb_test_multiple.
This patch is in preparation for software single step support on ARM in
GDBServer. It adds a new shared function regcache_raw_read_unsigned and
regcache_raw_get_unsigned so that GDB and GDBServer can use the same call
to fetch a raw register into an integer.
No regressions, tested on ubuntu 14.04 ARMv7 and x86.
With gdbserver-{native,extended} / { -marm -mthumb }
gdb/ChangeLog:
* Makefile.in (SFILES): Append common/common-regcache.c.
(COMMON_OBS): Append common/common-regcache.o.
(common-regcache.o): New rule.
* common/common-regcache.h (register_status) New enum.
(regcache_raw_read_unsigned): New declaration.
* common/common-regcache.c: New file.
* regcache.h (enum register_status): Move to common-regcache.h.
(regcache_raw_read_unsigned): Likewise.
(regcache_raw_get_unsigned): Likewise.
gdb/gdbserver/ChangeLog:
* Makefile.in (SFILES): Append common/common-regcache.c.
(OBS): Append common-regcache.o.
(common-regcache.o): New rule.
* regcache.c (init_register_cache): Initialize cache to
REG_UNAVAILABLE.
(regcache_raw_read_unsigned): New function.
* regcache.h (REG_UNAVAILABLE, REG_VALID): Replaced by shared
register_status enum.
This patch is in preparation for software single step support on ARM in
GDBServer. It refactors arm_*_software_single_step and sub-functions to
use regcache instead of frame to access registers so that the code can be
shared more easily between GDB and GDBServer.
Note also that since the intention is at some point to get rid of frame
completely in that function, memory reads have also been replaced by
read_memory_unsigned_integer rather than get_frame_memory_unsigned.
No regressions, tested on ubuntu 14.04 ARMv7 and x86.
With gdbserver-{native,extended} / { -marm -mthumb }
gdb/ChangeLog:
* arm-linux-tdep.c (arm_linux_sigreturn_next_pc_offset): New function.
(arm_linux_sigreturn_next_pc): Likewise.
(arm_linux_syscall_next_pc): Use regcache instead of frame.
(arm_linux_software_single_step): Likewise.
* arm-tdep.c (arm_is_thumb): New function.
(shifted_reg_va): Use regcache instead of frame.
(thumb_get_next_pc_raw): Likewise.
(arm_get_next_pc_raw): Likewise.
(arm_get_next_pc): Likewise.
(thumb_deal_with_atomic_sequence_raw): Likewise.
(arm_deal_with_atomic_sequence_raw): Likewise.
(arm_deal_with_atomic_sequence): Likewise.
(arm_software_single_step): Likewise.
* arm-tdep.h (struct gdbarch_tdep): Use regcache for syscall_next_pc.
(arm_get_next_pc): Use regcache.
(arm_deal_with_atomic_sequence): Likewise.
(arm_is_thumb): New declaration.
* regcache.c (regcache_raw_get_unsigned): New function.
* regcache.h (regcache_raw_get_unsigned): New function declaration.
Simon Marchi
Yao Qi
Joel Brobecker
Pedro Alves
Tom Tromey
Alan Hayward
Simon Marchi
Antoine Tremblay