gdb reverse execution: how to actually run tests for it?

[Hui Zhu]

On Wed, Aug 19, 2009 at 20:28, Pedro Alves<pedro@codesourcery.com> wrote:
> On Wednesday 19 August 2009 08:23:54, Jakob Engblom wrote:
>> > # Create an empty file named site.exp.
>> > # Create a directory named boards in the same location as site.exp.
>> > # Create a file named native-gdbserver.exp in the boards directory (see
>> below).
>> > # Set the DEJAGNU environment variable to point to the empty site.exp.
>> > # Run the testsuite with make check-gdb RUNTESTFLAGS="--target_board native-
>> > gdbserver".
>>
>> Should such files be part of the gdb source tree, so that the tests for reverse
>> can be run without having to set up a local special board?
>
> For the generic reverse execution tests --- reverse step, reverse next,
> reverse continue, run to breakpoint in reverse, etc., etc., I'd must prefer
> that we would get rid of the need for board files at all.  :-)
>
>  1. for native targets, the only reverse solution we currently support is
>  precord.  I can't see why we can't default to testing the reverse tests
>  with precord then.  We could still leave the possibility of a dejagnu
>  board variable changing this defaulting, but I don't think we need
>  it currently.  Of course, this would be filtered on selected targets.
>  Something along these lines in testsuite/lib/gdb.exp:
>
> proc run_reverse_tests_with_precord {} {
>
>  # Board requested it explicitly.  Might want to try
>  # precord against gdbserver.
>  if [target_info exists gdb,use_precord] {
>    return 1
>  }
>
>  if { [isnative] && ([istarget "i?86-*-linux*"] || [istarget "x86_64-*-linux*"]) } then {
>    # Nothing else supports precord, yet.
>    return 1
>  }
>
>  # Nope, don't use precord.  Maybe the target supports reverse
>  # debugging in some other way (e.g., a remote full system emulator)
>  return 0
> }
>
> Then have the tests check run_reverse_tests_with_precord instead of
> checking "target_info exists gdb,use_precord".
>

I think it's very useful.  Thanks.

Hui