Remote protocol extension for register ranges

[Fernando Nasser <fnasser at redhat dot com>]

Presently, the remote protocol can only read all registers of a target. 
This is OK for the context registers (the ones that are saved by the OD
on a context switch) but this is a serious limitation for machines that
have lots of additional registers.  It is just not feasible to read them
all at every "g" packet.

I would like to add parameters to the "g" packet.  Something similar has
been proposed before -- the only difference is that I would like the
parameters to be a register number or a register number range range.  

For instance: 

g82      Reads register 82
g31-40   Reads registers 31-40

Gdb would test for the acceptance of these types of packets by the stub
and fall back to the less efficient form if not (like it does for "P"
packets).

I really need this feature as do other people that are dealing with one
of the numerous microprocessors that have too many extra registers.  And
it is becoming quite urgent now.

What is the current thinking about this?  Are there other proposals I am
not aware of?  What are the maintainers position?

-- 
Fernando Nasser
Red Hat, Inc. - Toronto                 E-Mail:  fnasser@redhat.com
2323 Yonge Street, Suite #300           Tel:  416-482-2661 ext. 311
Toronto, Ontario   M4P 2C9              Fax:  416-482-6299