Re: [PATCH] gdb/py-inferior: Keep inferior threads in a map

[Tom Tromey <tom@tromey.com>]

>>>>> "Lancelot" == Lancelot SIX via Gdb-patches <gdb-patches@sourceware.org> writes:

Lancelot> The python code maintains a list of threads for each inferior.  This
Lancelot> list is implemented as a linked list.  When the number of threads grows
Lancelot> high, this implementation can begin to be a performance bottleneck as
Lancelot> finding a particular thread_object in the list has a complexity of O(N).

Thanks for the patch.

Lancelot> -  delete tmp;
Lancelot> +  auto it = inf_obj->threads->find (tp);
Lancelot> +  if (it != inf_obj->threads->end ())
Lancelot> +    {
Lancelot> +      it->second->thread = nullptr;
Lancelot> +      inf_obj->threads->erase (it);

Doesn't the erase implicitly also drop the 'thread' reference?
That is, I don't think the nullptr assignment is needed here.

Lancelot> -      PyTuple_SET_ITEM (tuple, i, thr);
Lancelot> +      PyTuple_SET_ITEM (tuple, i++, thr);

It's better to do the increment separately, in case PyTuple_SET_ITEM is
a macro that evaluates arguments more than once.

Tom