[patch][rfa]: Simulating and Debugging Multiple Processors

[Dave Brolley <brolley@redhat.com>]

Hi,

The attached patch adds two options to configrun-sid.in which enable 
loading programs into multiple cpus in a simulation and attaching 
multiple GDB debuggers to those cpus. The first option is:

--load PROCESSOR=NAME

o collects a mapping of processors to executables (may be specified more 
than once).
o reconciles $exec with any --load cpu=<name> which may have been  
specified (i.e. "cpu" specifically named on a --load option). The 
--load  option wins (with a warning) in case of conflict.
o generates a loader and mapper for each processor named 
<processor>-loader and <processor>-mapper respectively. These replace 
the current generic 'loader' and 'mapper' components. The generated 
loaders load the named executables and pass the data/insns to the 
generated mappers.

The generated mappers must still be connected to the appropriate 
memory/mappers/etc via hand written configury. This is just an extension 
of the current 'loader'-->'mapper' setup for single cpu simulations.

The second option is and extension of the -gdb=PORT option:

--gbdport PROCESSOR=PORT

This option generates a GDB interface component on the given port and 
interfaces it with the given processor. --gdb=PORT is equivalent to 
gdbport cpu=PORT. If both are specified and there is a conflict, the 
--gdbport option wins (with a warning).

Using these new options, and assuming that a configuration exists for a 
cpu with an additional processor 'cpu1', one could use

   <target>-sid program --gdb=1234 --load cpu1=program1 --gdbport cpu1=5678

to debug a multiple cpu simulation with 'program' being loaded into the 
main cpu and 'program1' being loaded into cpu1. One or more instance of 
GDB could be used to debug each on ports 1234 and 5678 respectively.

   <target>-sid --load cpu=program --gdbport cpu=1234 --load 
cpu1=program1 --gdbport cpu1=5678

is an equivalent command.

For all current ports, the difference in the generated config is that:

mapper  --> cpu-mapper
loader   --> cpu-loader
gdb   --> cpu-gdb
gdb-socket --> cpu-gdb-socket

All current options continue to work as expected.  Every pregenerated  
config is affected cosmetically, but not functionally. Pending approval, 
I will check in regenerated versions of each.

OK to commit?

Dave