Change CSE to record expressions as their values are pushed on the

Change CSE to record expressions as their values are pushed on the
stack; previously these expressions weren't recorded until their first
reference.  Fix `insert-stack-destination!' which was not setting up
the quantity associated with a stack slot correctly.  Fix stack model
which was not invalidating things correctly when pops occurred.
Change method for `invocation:special-primitive' to forget the
contents of all pseudo registers.