Emulation Alternatives

Tom R. Halfhill's article ``Emulation: RISC's Secret Weapon'' (April) fascinated me. But I have a question: With all the effort going into writing good run-time translators and emulators, why not put that effort into writing a good batch-mode binary-code translator?

Instead of translating at run time every time an 80x86 program needs to be run, such a translator would just translate the entire program once and store the translated binary on disk. This way, the run-time speed would be faster because no time would be spent translating on-the-fly, and more effort could be devoted to optimizing the output code. With this technique, virtually any program written for the 80x86 could easily be ported to the PowerPC (barring legal issues).

I hope that someone reading this letter will develop a program to do this. I think it would solve the compatibil ity problem--and make my life using the PowerPC easier as well.

Peter Shell

Pittsburgh, PA

Several other people wrote with the same idea, and it's already been done. Echo Logic (Holmdel, NJ) has a tool called FlashPort that translates 680x0 binaries into PowerPC binaries. Some Macintosh developers are using it to port all or parts of their 680x0-based software to the new Power Macs. DEC has a similar technology that translates legacy software written for its minicomputers to the Alpha-series RISC processors. It's not trivial, though, and there are legal issues that emulation neatly sidesteps.

--Tom R. Halfhill