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0 pointsstcredzero8y ago0 comments

It's a finite register machine which isn't just faithfully exposing the underlying architecture. Not something we often see. iirc SPIR and GNU Lightning are both finite register machines, but, to quote Douglas Adams, this has made a lot of people very angry and been widely regarded as a bad move.

TAOS operating system used such a virtual ISA, and was able to achieve around 90% efficiency of native code. The worst case was PowerPC which fell to 80%. That's pretty darn good, IMO.

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MaxBarraclough8y ago

Skimreading http://www.dickpountain.co.uk/home/computing/byte-articles/t... ( linked from https://news.ycombinator.com/item?id=9806607 , where you yourself commented )

Interesting OS. Its 'VP code' looks like a precursor to Java bytecode/HotSpot, but much more low-level and RISC-ey.

Inferno OS's 'Dis' VM took a similar to approach to VP code, if I understand correctly.

I presume that, in 1991 when the article was written, "JIT" wasn't yet in the techies' parlance. It's not used anywhere in the article.

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