82326d7ec8
We had the belief that m_type as an int32_t (and in at least one
place, an int64_t) burned in many places. This is going to make any kind of
re-encoding of TypedValues nearly impossible.
Redirect all such accesses via some helpers, so e.g.
a. cmpl(KindOfUninit, base[TVOFF(m_type)]);
becomes
emitCmpTVType(a, KindOfUninit, base[TVOFF(m_type)]);
which may do byte or dword access, depending on m_type's actual size. While
this is motivated by 7pack, I'm planning to route it through trunk to
prevent any more of the old style accesses from cropping up.