RE: [RFA] Patch to fix "reverse-next" command error

["Marc Khouzam" <marc dot khouzam at ericsson dot com>]

> -----Original Message-----
> From: gdb-patches-owner@sourceware.org 
> [mailto:gdb-patches-owner@sourceware.org] On Behalf Of Hui Zhu
> Sent: June-15-09 2:47 AM
> To: Michael Snyder; Marc Khouzam
> Cc: gdb-patches@sourceware.org
> Subject: Re: [RFA] Patch to fix "reverse-next" command error
> 
> On Mon, Jun 15, 2009 at 10:45, Michael 
> Snyder<msnyder@vmware.com> wrote:
> > Hui Zhu wrote:
> >>
> >> Ping.
> >
> > Hui, I rewrote your patch a little bit. ?I think we can use
> > gdbarch_skip_trampoline_code to detect the fact that we have
> > stepped into a trampoline (ie. "plt"). ?This is more general.
> >
> > Mark, please tell me if this patch fixes your original problem,
> > and Hui, please tell me if the patch is OK with you.
> >
> 
> This patch is OK with me.

I also tested this one and it works great for me as well.

Thanks

> 
> BTW, the patch that you sent include the prev one.
> 
> 
> Thanks,
> Hui
> 
> >> On Mon, May 11, 2009 at 15:07, Hui Zhu<teawater@gmail.com> wrote:
> >>>
> >>> PING
> >>>
> >>> On Wed, May 6, 2009 at 14:00, Hui Zhu <teawater@gmail.com> wrote:
> >>>>
> >>>> Hi Michael,
> >>>>
> >>>> I try this issue with cvs-head. ?It still affect cvs-head.
> >>>> And I try the patch, it can fix this issue. ?It's time 
> close to 7.0
> >>>> branch. ?So could you please help me review it?
> >>>>
> >>>> The attachment is the new patch follow cvs-head.
> >>>>
> >>>> 2009-05-06 ?Hui Zhu ?<teawater@gmail.com>
> >>>>
> >>>> ? ? ?* infrun.c (handle_inferior_event): Make inferior step if it
> >>>> ? ? ?stepping over a function call in reverse , and stop at the
> >>>> ? ? ?start address of the function.
> >>>>
> >>>> Thanks,
> >>>> Hui
> >>>>
> >>>> On Thu, Jan 22, 2009 at 17:00, teawater 
> <teawater@gmail.com> wrote:
> >>>>>
> >>>>> Hi guys,
> >>>>>
> >>>>> This patch is for bug in
> >>>>> http://sourceware.org/ml/gdb/2009-01/msg00146.html
> >>>>>
> >>>>> This issue is because sometime the inferior is already 
> in function
> >>>>> start address (i.e. plt), set a breakpoint and continue 
> will make
> >>>>> "reverse-next" work error.
> >>>>>
> >>>>> This patch make inferior step if it reverse step and stop at the
> >>>>> function start address.
> >>>>> It tested OK with process record patch and testsuite 
> gdb.twreverse in
> >>>>> branch reverse-20081226-branch.
> >>>>>
> >>>>> 2009-01-22 ?Hui Zhu ?<teawater@gmail.com>
> >>>>>
> >>>>> ? ? ? * infrun.c (handle_inferior_event): Make inferior 
> step if it
> >>>>> ? ? ? stepping over a function call in reverse , and stop at the
> >>>>> ? ? ? start address of the function.
> >>>>>
> >>>>> OK for mainline?
> >>>>>
> >>>>> Thanks,
> >>>>> Hui
> >>>>>
> >>
> >
> >
> > 2009-06-14 ?Hui Zhu ?<teawater@gmail.com>
> > ? ? ? ? ? ?Michael Snyder ?<msnyder@vmware.com>
> >
> > ? ? ? ?* infrun.c (handle_inferior_event): Reverse-next 
> through trampoline.
> >
> > Index: infrun.c
> > ===================================================================
> > RCS file: /cvs/src/src/gdb/infrun.c,v
> > retrieving revision 1.387
> > diff -u -p -r1.387 infrun.c
> > --- infrun.c ? ?11 Jun 2009 11:57:46 -0000 ? ? ?1.387
> > +++ infrun.c ? ?15 Jun 2009 02:39:51 -0000
> > @@ -3623,9 +3623,17 @@ infrun: not switching back to stepped th
> >
> > ? ? ?Note that step_range_end is the address of the first 
> instruction
> > ? ? ?beyond the step range, and NOT the address of the last 
> instruction
> > - ? ? within it! */
> > + ? ? within it!
> > +
> > + ? ? Note also that during reverse execution, we may be stepping
> > + ? ? through a function epilogue and therefore must detect when
> > + ? ? the current-frame changes in the middle of a line. ?*/
> > +
> > ? if (stop_pc >= ecs->event_thread->step_range_start
> > - ? ? ?&& stop_pc < ecs->event_thread->step_range_end)
> > + ? ? ?&& stop_pc < ecs->event_thread->step_range_end
> > + ? ? ?&& (execution_direction != EXEC_REVERSE
> > + ? ? ? ? || frame_id_eq (get_frame_id (get_current_frame ()),
> > + ? ? ? ? ? ? ? ? ? ? ? ? ecs->event_thread->step_frame_id)))
> > ? ? {
> > ? ? ? if (debug_infrun)
> > ? ? ? ?fprintf_unfiltered (gdb_stdlog, "infrun: stepping 
> inside range
> > [0x%s-0x%s]\n",
> > @@ -3762,10 +3770,21 @@ infrun: not switching back to stepped th
> > ? ? ? ? ? ? ? ? ?keep_going (ecs);
> > ? ? ? ? ? ? ? ? ?return;
> > ? ? ? ? ? ? ? ?}
> > - ? ? ? ? ? ? /* Normal (staticly linked) function call return. ?*/
> > - ? ? ? ? ? ? init_sal (&sr_sal);
> > - ? ? ? ? ? ? sr_sal.pc = ecs->stop_func_start;
> > - ? ? ? ? ? ? insert_step_resume_breakpoint_at_sal (sr_sal, 
> null_frame_id);
> > + ? ? ? ? ? ? if (gdbarch_skip_trampoline_code(current_gdbarch,
> > + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?get_current_frame (),
> > + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?stop_pc))
> > + ? ? ? ? ? ? ? {
> > + ? ? ? ? ? ? ? ? /* We are in a function call trampoline.
> > + ? ? ? ? ? ? ? ? ? ?Keep stepping backward to get to the 
> caller. ?*/
> > + ? ? ? ? ? ? ? ? ecs->event_thread->stepping_over_breakpoint = 1;
> > + ? ? ? ? ? ? ? }
> > + ? ? ? ? ? ? else
> > + ? ? ? ? ? ? ? {
> > + ? ? ? ? ? ? ? ? /* Normal function call return (static or 
> dynamic). ?*/
> > + ? ? ? ? ? ? ? ? init_sal (&sr_sal);
> > + ? ? ? ? ? ? ? ? sr_sal.pc = ecs->stop_func_start;
> > + ? ? ? ? ? ? ? ? insert_step_resume_breakpoint_at_sal (sr_sal,
> > null_frame_id);
> > + ? ? ? ? ? ? ? }
> > ? ? ? ? ? ?}
> > ? ? ? ? ?else
> > ? ? ? ? ? ?insert_step_resume_breakpoint_at_caller 
> (get_current_frame ());
> >
> >
>