I apologize for the exception frame format size change.  Some history:
On the 68000, from which this code long ago originated, 2 bytes of padding
were required to longword align the exception stack (the HW pushed a 2-byte
PSW and 4-byte PC).  However, with the 68010 and beyond, the frame was
already aligned and the 2 bytes of padding only threw it out of alignment.
I meant to fix this from day 1 (back in 1987) but it never happened until
a couple of years ago when I put in 68040 support.  Since so many things
changed at that point anyway, I decided to go ahead and fix it while I was
in there.  I couldn't just remove the pad word because it was being used
so I extended it by 2 bytes.  Checking the RCS logs, the affected files I
see are:

	cpu.h		(clockframe)
	frame.h		(new pad)
	reg.h		(PC no longer included)
	genassym.c	(new constants)
	kgdb_glue.c	(stack pop in asm statement)
	kgdb_stub.c	(regs_to_gdb copy)
	locore.s	(tons o changes)

	hpux_compat.c	(ptrace code)

	kern_exit.c	(GETPS macro)
	sys_process.c	(location of PS/PC)


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