Re: Question: Checking register value in buffer

Daniel Jacobowitz
2005-05-19T03:07:11Z

On Wed, May 18, 2005 at 07:22:56PM -0700, Richard Henderson wrote:
> On Thu, May 19, 2005 at 12:04:44PM +1000, Joel Brobecker wrote:
> > LONGEST rav = extract_signed_integer (buf, 8)
> >
> > and then do the test using integer arithmetics. But then I'm not guarantied
> > that LONGEST is at least 64bit long, am I.
>
> It had better be, or the rest of alpha_next_pc is broken too.
>
> Since it isn't, or isn't reported to be, you might as well
> assume it is large enough.
>
> > How are these sort of checks usually done in GDB?
>
> In gcc-land we have a "need_64bit_hwint" bit in config.gcc, and it
> is set for targets that require the equivalent of LONGEST be at
> least 64 bits, or we error out of configure.
>
> Dunno what's done in gdb.

Because GDB doesn't have the same performance concerns with LONGEST
that GCC does with H_W_I, it's the biggest thing we can find. Joel,
the definitions in defs.h are pretty clear - it will only be smaller
than 64-bit if we're really strapped for a 64-bit type, and if that's
the case, there's no way you're loading 64-bit ELF files.

--
Daniel Jacobowitz
CodeSourcery, LLC