Yes, I saw those references already. Still not enough information...
What, in particular, sets HLVM apart. Surely not just the native machine types?
Are you handling array references in some unusually efficient manner? Are you avoiding unnecessary copy-on-writes of large arrays by some form of whole-program analysis? I still don't have a handle on HLVM...
http://www.ffconsultancy.com/ocaml/hlvm/
http://flyingfrogblog.blogspot.com/2009/03/performance-ocaml-vs-hlvm-beta-04.html