Timings for tak

[pop at cs.umass.edu]

[copy to pop-forum%uk.co.hp.lb at nsfnet-relay.ac.uk]

I obtained the following results for  tak(18,12,6) on a SUN/3 running POPLOG.
Memoisation is not in this case a big win over C, as it is for tak(24,16,8).
I do not have access to the compiler for the POP-11 system dialect, which
does considerably more optimisation. Roughly speaking, generating
fixed-integer code rather than code for general numbers (Common Lisp spec)
gives a factor of 2 speedup, while any other optimisations available to
the user of the incremental compiler gain about 10% extra.                     

POP-11(POPLOG,optimised,incremental)  SUN3/60        0.83
POP-11(POPLOG,memoised,generic)       SUN3/60        0.67
C     (cc -c tak.c)                   SUN3/60        0.37


Robin Popplestone.