Need advice on bounds checking approaches

[Jeffrey A Law]

  In message < ms8zz4rr51.fsf@gkm-dsl-194.ascend.com >you write:
  > > I can't think of any support on ppc for this that isn't already
  > > represented in the machine description through the TRAP RTXs.
  > 
  > Conditional traps aren't widely available (only i960, m68k, powerpc,
  > sparc), so that approach doesn't help all that much for portability.
  > Is there something more that I'm missing?
The PA has conditional traps.  We've just never bothered adding them
the MD file.

jeff