You would have to compile multiple versions to support multiple architectures, but the implication that NaCl is fundamentally tied to x86 is incorrect.
NativeClient's use of segmentation on x86 is just an implementation detail of how the sandbox is implemented on that architecture, AFAIK. NaCl doesn't fundamentally require that any target architecture support segmentation.
It better have very strong support for ARM, too. It already bugs me that Google wants to use Intel chips so much for some of their products, that they end up making them too expensive, and as such a failure in the market. See Google TV, and now even Chromebooks (which should've been much cheaper).
If they would've started off directly with ARM chips, they wouldn't have had the same problem, because the products would've been priced more reasonably (unless manufacturers wanted to put the "early adopter tax" on them, too).
Yep sorry for the misinformation, I hadn't read much about it recently. Seems whatever it does on amd64 (or in PNaCl at a guess) is also how it works on arm (7% slowdown from looking at the FAQ).
You would have to compile multiple versions to support multiple architectures, but the implication that NaCl is fundamentally tied to x86 is incorrect.
NativeClient's use of segmentation on x86 is just an implementation detail of how the sandbox is implemented on that architecture, AFAIK. NaCl doesn't fundamentally require that any target architecture support segmentation.