[virtmach] parrot VM?

Manoj Plakal virtmach@iecc.com
Fri, 12 Jul 2002 17:15:06 -0500

Ian Piumarta wrote (Fri, Jul 12, 2002 at 11:37:01PM +0200) :
> When dynamically translating to native code at runtime it's much easier to
> generate register-based native code off a stack-based bytecode than it is
> to do it off a register-based one (or even convert back to pure
> stack-based code for some architectures which have no registers).  One
> reason for this is that the stack manipulation in the bytecode has lots of
> implicit information in it (e.g., lifetimes) that would be missing in
> register-based code.

	That's interesting. But are you talking about extra information
	in the bytecode, or are you referring to simply popping a value 
        off the stack as ending its lifetime? Registers get overwritten too,
	so that can convey the same information. 

        Do you have a short example of strictly more information available
	in a stack-VM bytecode sequence than a register-VM sequence?