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Re: Lucid 3.0.2 Optimization botch



    Date: Tue, 16 May 89 05:45:56 PDT
    From: Jon L White <jonl@lucid.com>

    The more desirable thing to do is to put the whole "dcode" down one 
    more level of indirection through the symbol-function cell of the 
    generic functon.  This is effectively what PCL's 'make-trampoline' 
    function does, but unfortunately that is not a very efficient approach 
    when you consider how most compilers will compile it.  Something akin 
    to the "mattress-pads" in John Foderaro's code (in the fin.lisp file) 
    could probably be done for many other implementations as well.  I don't 
    know who wrote the Lucid specific parts of fin.lisp, but I can supply 
    the Lucid-specific code sequences of corresponding "mattress-pad"'s for 
    several machines to anyone who wants to give it a try.

If you rewrite the Lucid part of FIN to do this mattress-pad stuff then
I can install it in PCL and fix this longstanding problem.

    Just doing the tail-recursive exit will probably make the matter 
    essentially moot for all practical purposes.

The problem crops up all the time here for people using PCL in Lucid
Lisp.
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