Re: CRIS port; frame cleanup crash

[Orjan Friberg <orjan dot friberg at axis dot com>]

Andrew Cagney wrote:
> And callfuncs.exp, and a sequence like:
>
> ./gdb callfuncs
> (gdb) break add
> (gdb) break main
> (gdb) run
> (gdb) print add(1,2)
> (gdb) bt
> (gdb) print add(3,4)
> (gdb) bt
> add(3,4)
> <dummy frame>
> add (1,2)
> <dummy frame>
> main ()
> (gdb)
>
> is a good check of dummy frames

Ok, backtrace doesn't work at all.  (find_dummy_frame() isn't able to 
locate the dummy frame because fp doesn't match dummyframe->top.)  A 
couple of questions regarding this:

frame_align(): this function is only concerned with architecture issues, 
and not ABI issues, right?  What I mean is that we're not mimicking 
anything the compiler would do the way we do when we set up arguments 
for a function call.  If the architecture has no alignment restrictions 
on the stack, then we shouldn't have to do any stack alignment, although 
the compiler might align it for performance reasons.

push_dummy_call(): the CRIS code allocates more space on the stack than 
is actually needed; is this going to cause me problems?  Since, as I 
understand it, the SP returned from push_dummy_call() must match the SP 
unwound when unwinding the dummy id I'm thinking I'll either have to get 
rid of the over-allocation on the stack (preferred) or compensate for it 
when unwinding the dummy id.  Is this correct?

FWIW, everything up to and including the cmp10(...) test in 
callfuncs.exp works, so at least the argument setup seems ok.

Thanks,
Orjan

--
Orjan Friberg
Axis Communications