Re: Is there single step debugging support being added to aarch64-linux?

[Prafull Suryawanshi <prafull.net@gmail.com>]

I am using kgdb and trying to do single step (software single step).
I see that infrun loops. (I enabled remote_debug option and compiled
gdb 7.7 as 7.9 has issue with connection)

infrun: clear_proceed_status_thread (Thread 3462)
infrun: clear_proceed_status_thread (Thread 3444)
infrun: proceed (addr=0xffffffffffffffff, signal=GDB_SIGNAL_DEFAULT, step=1)
infrun: resume (step=1, signal=GDB_SIGNAL_0), trap_expected=1, current
thread [Thread 3462] at 0xffffffc00021014c
Sending packet: $Hcd86#7d...Ack
Packet received: OK
Sending packet: $s#73...Ack
infrun: wait_for_inferior ()
Packet received: T05thread:0d86;
infrun: target_wait (-1, status) =
infrun:   42000 [Thread 3462],
infrun:   status->kind = stopped, signal = GDB_SIGNAL_TRAP
infrun: infwait_normal_state
infrun: TARGET_WAITKIND_STOPPED
Sending packet: $g#67...Ack
Packet received:
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
infrun: stop_pc = 0xffffffc000210150
Sending packet: $mffffffc000210150,4#4d...Ack
Packet received: fd030091
Sending packet: $mffffffc00021014c,4#7f...Ack
Packet received: fd7ba3a9
Sending packet: $mffffffc000210150,4#4d...Ack
Packet received: fd030091
infrun: stepping inside range [0xffffffc00021014c-0xffffffc000210170]
Sending packet: $Z0,ffffffc00021014c,4#c8...Ack
Packet received: OK
infrun: resume (step=1, signal=GDB_SIGNAL_0), trap_expected=0, current
thread [Thread 3462] at 0xffffffc000210150
Sending packet: $Hc0#db...Ack
Packet received: OK
Sending packet: $s#73...Ack
infrun: prepare_to_wait

Then I build the gdb using arch_dump enable option
gdbarch_dump: gdbarch_software_single_step_p() = 0

I see that in gdb code, function aarch64_linux_software_single_step not present.

I guess above loop expected if aarch64_linux_software_single_step absent, right?

Thanks,
Prafull

On Mon, Jun 15, 2015 at 4:08 PM, Andreas Schwab <schwab@suse.de> wrote:
> Prafull Suryawanshi <prafull.net@gmail.com> writes:
>
>> I am trying it on 64 bit armv8 system but not able to doit.
>> Found issue in gdb source code and absence of this function in
>> aarch64-linux-tdep.c file. Anyone knows if support getting added or
>> not?
>
> The stepi command is working fine on aarch64.  What do you get if you
> try it?
>
> Andreas.
>
> --
> Andreas Schwab, SUSE Labs, schwab@suse.de
> GPG Key fingerprint = 0196 BAD8 1CE9 1970 F4BE  1748 E4D4 88E3 0EEA B9D7
> "And now for something completely different."