powerpc remote target registers
Tue Dec 2 05:23:00 GMT 2003
Andrew Cagney wrote:
>> Now, arguably this is a problem with GCC/GAS/GLD: there is a machine
>> type specifically for mpc860 with the correct register definitions,
>> instead of "common" with the correct register definitions. However
>> GCC/GAS don't allow you to set that when compiling objects, and LD
>> appears to ignore my request to set it explicitly when linking (using
>> -A powerpc:mpc860). That shouldn't really be needed anyway, as it
>> should be implied by a compile with -mcpu=860, but GCC doesn't pass
>> anything to GAS/the linker to reflect that. Sigh.
>> However I would say that GDB is also mistaken for not initializing the
>> packet buffer in remote_fetch_registers() to 0 first, so that
>> registers that aren't supplied by the remote target don't have
>> uninitialised data, which may include an "x" in them.
> I don't think this fixes the bug. It will fill each nibble of the
> altivec registers with (0 - '0') instead of zero (you should see this
> with "maint print raw-registers").
Ah, it still came up with 0 until I did that so I thought that was it.
> Suggest instead changing the for loop filling in regs so that it
> doesn't run off the end of the NUL terminated buf (I think this is the
> real bug).
But then the registers aren't marked as cached at all, so they're now
requested from the target each time you do "info all-registers", even
though they come up with 0s. Should I pretend the registers not supplied
by the target were 0, or should I mark them as unavailable (i.e. the same
as what having an "x" does) so at least it's consistent?
eCosCentric http://www.eCosCentric.com/ The eCos and RedBoot experts
--["No sense being pessimistic, it wouldn't work anyway"]-- Opinions==mine
More information about the Gdb-patches