Re: cgen, GNU gdb/sim, and full system simulation

Peter Gavin <[email protected]> Fri, 18 May 2012 14:46:17 +0200
Newsgroups gmane.comp.emulators.sid.devel
Message-ID <CAKEMJMp8RP3xhvptyWQn4yqbTaXXOD7e4oSB2c4bg__ARrjtEg__48802.9134263799$1337345199$gmane$org@mail.gmail.com>
Hi Frank, thanks for the response.

> On Fri, May 11, 2012 at 01:57:11PM +0200, Peter Gavin wrote:
> Indeed. =C2=A0For full-system simulators, some projects have used the sid
> framework instead of gdb/sim.

Ok.  But we're primarily doing this for GDB, and I suppose gdb can't
use sid, is that right?

> Actually, instruction fetching code can be hand-written in either
> gdb-sim (see e.g. sim/m32r/mloop.in extract-*) or sid frameworks
> (sid/component/cgen-cpu/m32r/m32rbf.cxx step_insns), and so that code
> can map all it likes.

Hmm, I'll look into this.

> To me, the more interesting question would be the choice to model
> virtual memory as a separate component between the CPU and the memory
> and I/O buses (which would suite sid's modeling very well), vs
> something purely internal to the CPU model.

Yeah, I was hoping I could just define a memory in the .cpu file with
define-hardware and have custom get and set methods, but it looks like
that won't work :)

-Pete