While you may be right with regards to the file size (although most SSA-representations are not built for small size, there is quite some potential to reduce it, imho), you'll have to do register allocation/spilling/etc. in your VM/compiler anyway and that is easier and faster on SSA[1, and more]. The dominance frontiers algorithm is actually not that good imho, there are better options[2], especially considering that one may not want to construct an unnecessary dominance tree in an Interpreter/VM. Now, I have no experience how much overhead SSA-deconstruction inflicts when lowering to machine code.

[1] http://www.cdl.uni-saarland.de/projects/ssara/ [2] http://www.cdl.uni-saarland.de/projects/ssaconstr/

Yes, I'm associated with that group.