gdb: don't handle i386 k registers as pseudo registers

I think that i386 k registers are raw registers, and therefore shouldn't
be handled in the various functions handling pseudo registers.

What tipped me off is the code in i386_pseudo_register_read_into_value:

      else if (i386_k_regnum_p (gdbarch, regnum))
	{
	  regnum -= tdep->k0_regnum;

	  /* Extract (always little endian).  */
	  status = regcache->raw_read (tdep->k0_regnum + regnum, raw_buf);

We take regnum (the pseudo register number we want to read), subtract
k0_regnum, add k0_regnum, and pass the result to raw_read.  So we would
end up calling raw_read with the same regnum as the function received
which is supposedly a pseudo register number.

Other hints are:

 - The command `maint print raw-registers` shows the k registers.
 - Printing $k0 doesn't cause i386_pseudo_register_read_into_value to be
   called.
 - There's code in i387-tdep.c to save/restore the k registers.

Remove handling of the k registers from:

 - i386_pseudo_register_read_into_value
 - i386_pseudo_register_write
 - i386_ax_pseudo_register_collect

Change-Id: Ic97956ed59af6099fef6d36a0b61464172694562
Reviewed-by: John Baldwin <jhb@FreeBSD.org>

0 files changed, 0 insertions, 0 deletions