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Yes, they are special, but this would be MORE special:



    Date: Wed, 14 Jun 89 05:32:41 PDT
    From: gyro@kestrel.edu (Scott Layson)

    What I'd propose is different from the current Symbolics designs in
    that there is no microcode

Sounds like the current Symbolics design to me (current = Ivory).
It's a highly-pipelined, NON-microcoded processor.  There are a number
of RISCy ideas, although I don't think it would be considered a real
RISC processor.  Many of the things that used to be done in ucode are
now done in macrocode, taking advantage of the pipelining.  For
instance, BITBLT is now macrocoded.  I think it still does generic
operations in hardware, rather than having a macrocoded tag-dispatch
instruction.  This means that the common case of fixnum arithmetic
will be done in one cycle.