[plt-scheme] Nanojit - an alternative to LLVM

A little while ago someone asked about using LLVM as an alternative
compiler backend to Lightning. Another alternative, with perhaps a
better set of tradeoffs (much smaller but lower performance than LLVM)
is Nanojit, used in the pre-release versions of Firefox:

  https://developer.mozilla.org/En/Nanojit

It currently support x86 and ARM. I believe Sparc support is at least
on the wishlist.

[Another alternative is libjit, but their website is makes ridiculous
claims, which doesn't inspire confidence in the project.]

[Implementing a trace based compiler should lead to publishable
research, so it might be more appealing to those likely to actual do
the work.]

N.