"Piston slap" appears to be different than I remember.  I always thought
that piston slap was the skirts of the pistons having excessive clearance
and they made a slapping sound as they passed the rollover point on
the rod at bottom center.  This usually occurs with age as the skirts of
the pistons wear.  Some cars even add an extra ring down around the
skirt.  If the pistons and cylinders are mismatched, they can gall along
the bottom of the cylinder when the pistons get hot, really screwing up
an engine.  Most pistons are graphite or molybdenum coated to ease this
spot during break-in.

I've never heard bearing failure called piston slap before, but then I
am not a mechanic.

malcolm