[cv5005]

A good compiler will only do that if the register spilling is more efficient than using more stack varibles, so I don't really see the problem.

[Joker_vD]

You can't operate on stack variables without loading them into the registers first, not on RISCs anyway. My main point is that this memory-shuffling traffic is unavoidable in non-leaf functions, so an extremely large amount of available registers doesn't really help them.