[pjmlp]

> JVM bytecode is truly portable, whereas target ABI details leak into LLVM IR. A biggie is 32 bit vs 64 bit LLVM IR.

From a few LLVM meetings and Apple's work on bitcode packaging, I think there is some work to make LLVM IR actually architecture independent.

[gsnedders]

PNaCl is noteworthy here too, insofar as its IR is very much based on LLVM IR (but portable and stable).