RE: [PATCH 05/10] python: Introduce gdb.RecordAuxiliary class.

["Metzger, Markus T" <markus.t.metzger@intel.com>]

Hello Felix,

> Auxiliary instructions are no real instructions and get their own object
> class, similar to gaps. gdb.Record.instruction_history is now possibly a
> list of gdb.RecordInstruction, gdb.RecordGap or gdb.RecordAuxiliary
> objects.
> 
> This patch is in preparation for the new ptwrite feature, which is based on
> auxiliary instructions.
> 
> 2019-05-29  Felix Willgerodt  <felix.willgerodt@intel.com>
> 
> gdb/ChangeLog:
> 	* py-record-btrace.c (btpy_insn_or_gap_new): Removed.
> 	(btpy_item_new): New function.
> 	(btpy_list_item): Call btpy_item_new instead of recpy_insn_new.
> 	(recpy_bt_replay_position): Call btpy_item_new instead of
> 	btpy_insn_or_gap_new.
> 	(recpy_bt_begin): Call btpy_item_new instead of btpy_insn_or_gap_new.
> 	(recpy_bt_end): Call btpy_item_new instead of btpy_insn_or_gap_new.
> 	* py-record.c (recpy_aux_type): New static object.
> 	(recpy_aux_object): New typedef.
> 	(recpy_aux_new, recpy_aux_number, recpy_aux_data): New function.
> 	(recpy_aux_getset): New static object.
> 	(gdbpy_initialize_record): Initialize gdb.RecordAuxiliary type.
> 
> gdb/doc/ChangeLog:
> 	* python.texi (gdb.RecordAuxiliary): New documentation.
> 
> ---
>  gdb/doc/python.texi           | 13 +++++++
>  gdb/python/py-record-btrace.c | 22 +++++++----
>  gdb/python/py-record.c        | 73 ++++++++++++++++++++++++++++++++++-
>  gdb/python/py-record.h        |  3 ++
>  4 files changed, 103 insertions(+), 8 deletions(-)

Looks good to me but I can't approve it.

> @@ -172,6 +173,14 @@ btpy_insn_or_gap_new (thread_info *tinfo, Py_ssize_t
> number)
>        return recpy_gap_new (err_code, err_string, number);
>      }
> 
> +  const struct btrace_insn *insn = btrace_insn_get (&iter);
> +
> +  gdb_assert (insn != nullptr);

This must be true because we checked btrace_insn_get_error () before.  To make it
more obvious, we could rewrite the function to call btrace_insn_get () first and check
the returned btrace_insn pointer.  There's no need to check the error code, I think.
In the worst case, we'll end up with a gap that says 'success'.

> @@ -470,7 +479,7 @@ btpy_list_item (PyObject *self, Py_ssize_t index)
>    number = obj->first + (obj->step * index);
> 
>    if (obj->element_type == &recpy_insn_type)
> -    return recpy_insn_new (obj->thread, RECORD_METHOD_BTRACE, number);
> +    return btpy_item_new (obj->thread, number);
>    else
>      return recpy_func_new (obj->thread, RECORD_METHOD_BTRACE, number);
>  }

Isn't this code just creating list item objects?

Thanks,
Markus.

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