LLVM-MOS targets 6502 and so goes out of its way to use as few of the hardware stack as possible: it does global program optimization, figuring out what calls w

LLVM-MOS targets 6502 and so goes out of its way to use as few of the hardware stack as possible: it does global program optimization, figuring out what calls what, and what functions don't need to be reentrant so it could allocate as many of activation records as possible statically, FORTRAN-style.