How does the compiler avoid creating a closure here?

[Andrei Alexandrescu via Digitalmars-d]

Consider http://dpaste.dzfl.pl/fork/ae75176d7d3f.

It's a bit roundabout but in brief it instantiates a template with a 
nested function. The nested function, in turn, uses a parameter in its 
environment. By the canon, that function needs to create a closure with 
dynamically-allocated environment.

To my surprise, however, the generated code uses no closure (disassembly 
at http://goo.gl/ti23W0) yet works correctly.

How come? Can anyone explain to me where x (used by the nested function) 
is stored?


Thanks,

Andrei

P.S. I'd like to thank Iain and Vladimir for making it so easy and 
pleasing to inspect and share code snippets with dpaste and asm.dlang.org.