With MSVC it seems that this class and its constructor is colliding
with the one in ir_variable_refcount.cpp. Rename the class here to
avoid the collision.
This is a bit of a hack. Can the two variable_entry classes be merged
and shared?
I'd missed putting in the actual "find structures to split" part, so
most of the code didn't do anything. I was running on too large of an
app and assuming the lack of progress was elsewhere.
This doesn't do anything if your structure goes through an uninlined
function call or if whole-structure assignment occurs. As such, the
impact is limited, at least until we do some global copy propagation
to reduce whole-structure assignment.