Re: GDB on SGI Irix 6.5

["Eli Zaretskii" <eliz@is.elta.co.il>]

> Date: Mon, 30 Apr 2001 13:01:33 -0400
> From: Andrew Cagney <ac131313@cygnus.com>
> 
> >   - Should I make the change in tm-irix5.h, or should I leave it alone
> >     and create irix6x.h?  The issue here is that perhaps Irix 5 did
> >     work like tm-irix5.h says, and I won't want to break that.
> 
> I think everyone has agreed on tm-irix6.h.

Yes; tm-irix6.h it is.

> >   - What should I do about the different ABIs?  At least 3 come to
> >     mind: O32, N32, and N64.  They have subtly different layouts of
> >     registers, so if I need to set things up for more than a single
> >     ABI, I'll need to know what's the current say-so about how this
> >     should be done (e.g., does gdbarch has some functionality for
> >     dynamically computing the registers array?).
> 
> By subtle differences in registers do you mean the register use or
> layout?

The names of some registers are different, and some of the registers
defined by tm-irix3.h and used by tm-irix5.h, evidently for O32 and
older ABIs, don't exist in N32 and 64, according to my references.

> mips-tdep.c:mips_gdbarch_init() is hopefully already detecting the ABI
> and setting things up to handle the register usage differences.

Not really.  I discovered that tm-irix3.h and tm-irix5.h are totally
wrong for N32 (that's why GDB crashed for me).  In particular, they
define FP_REGNUM incorrectly.

> With regard to register layout, the MIPS still, unfortunatly, uses a
> static configuration.  multi-arch can support dynamic register layouts,
> it is just not implemented for MIPS.

I'll try to make tm-irix6.h do a better job (no promises ;-).

Thanks for the feedback.