[arm-gnu] how to add new instruction in gcc

[Nick Clifton]

Hi Luca,

> Hi nick, hi all
> I tried and build the ARM simulator, but I really was never
> able to get it working for an arm-linux-pxa270-softfloat-gnu
> platform (forgive the fantasy name).
> Am I missing something?
> I thought that the simulator was working just with not-so-modern
> arm platforms and, most of all, not with OS (linux) support.

The ARM simulator used by GDB is not a platform simulator at all.  It 
does not simulate any boards or test environments.  It only simulates an 
ARM CPU.  Hence it is not really possible to simulate an entire OS using it.

The simulator's purpose is to allow testing and debugging of ARM code 
generated by GCC and that is all.  So it should be sufficient for you if 
you just want to test the generation of new instructions, but if you 
want to test these instructions in an simulated run-time environment 
then you are going to need another tool.  You might like to look at the 
SID project:

   http://sources.redhat.com/sid/

Alternatively there are commercial simulators that are out there as well.

Cheers
   Nick