
Like the original MIPS, HPPA has the MSB of an SNaN set. However, it has different rules for silencing an SNaN: (1) msb is cleared and (2) msb-1 must be set if the fraction is now zero, and (implementation defined) may be set always. I haven't checked real hardware but chose the set always alternative because it's easy and within spec. Signed-off-by: Richard Henderson <rth@twiddle.net>