What prevents an efficient Haskell virtual machine (like JVM)?

Question

I have been wondering, what prevents the development of an efficient virtual machine like JVM or PyPy for Haskell (except maybe development effort)? Is it the language structure? I think languages, that are harder to interpret efficiently (like Python, being very dynamic), already have decent VMs.

Also, if nothing is obstructing such an implementation, would STG be a good target "bytecode", since all optimizations are done on Core?

Are there any articles or blog posts that discuss this topic?

EDITs:

• I am aware of HaLVM, but I don't think it is what I mean.
• I am also aware of runhaskell, but it is not efficient at all.

Answer 1

What prevents an efficient Haskell virtual machine?

Nothing - there already has been one, Daan Leijen's LVM. It was efficient enough to be used for the runtime system of Helium (the Haskell "teaching language" from Utrecht University).

That said I don't know if it is used these days, so the question "What prevents an efficient Haskell virtual machine?" could be answered as manpower, continuous investment, etc. When Haskell already has a good compiler, a good VM is a luxury as Paulo Pinto noted already.

Answer 2

I am not aware of any technical restriction applying here. There is a language called Frege, semanticaly close to Haskell, that targets JVM. So it is just that nobody has considered so far that a Haskell-to-JVM compiler was worth the effort. Indeed, as a JVM-skeptic, I wonder what that would bring. If it is just intermediate language portability, I'd rather work on LLVM or on a pre-built binary farm.