Faster stepping amidst breakpoints

[Maxim Grigoriev <maxim@tensilica.com>]

Hello GDB community,

Has anyone tried to optimize the GDB protocol by letting
the remote agent plant and unplant breakpoints when the
target resumes and stops, rather than having GDB do it
over the wire with round-trip latency on every single
breakpoint plant&  unplant request?

Certain GDB operations involve a lot of single-stepping,
which can be really slow on certain targets (especially
embedded targets) because of that latency.

In principle, GDB can query the remote agent to decide
whether to apply this optimization.  And the remote agent
must be careful not to plant any breakpoint at the current
PC when single-stepping.  There are likely other
considerations, but at a glance, it seems doable.
So am curious whether there's any particular reason
it wasn't done (that we could see).

Thanks,
-- Maxim