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[no subject]

    GLS@MIT-AI 02/23/79 02:06:32 Re: OPTIMIZE in pass 1 of QCMP (QCP1)
    The optimizer as it is currently structured seems to have
    the general problem that at the point an optimizer is applied to
    a form, the subforms of that form are not optimized.  As a result,
    a form like   (EQUAL X (OR))  optimizes only to  (EQUAL X 'NIL),
    whereas if  (EQUAL X 'NIL) were originally written, it would optimize
    first to  (EQ X 'NIL)  and thence to  (NOT X).  The optimizer seems
    to operate top-down, in effect, but this example indicates that
    it were perhaps better arranged bottom-up.

The optimizer is called by some of the individual optimizers to avoid
this problem.  If some neglect to do so, they can be fixed.
It can't be done bottom-up without being a separate
pass.  I don't think that's worth it.