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The fial memory reference in this instruction trade could be removed by storing a pointer to each method's UEP in vtable (and itable) entries, as C++ doeadoes. This has not been done because it would then be difficult for the interpreter to use the vtables. (An earlier version of the system had two-word vtables, to display both kinds two entry points on an equal footing, but this led to complexities and, worst of all, race conditions.) It is an interesting problem to try to invert the preference the current design gives to the interpreter; the interpreted entry point would have to be hidden somewhere at a fixed offset from the method's compiled entry point, but not close enough to disturb the tuning of the VEP.

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