This is was a very mechanical patch where I basically first renamed SILNodes.def
and then just kept fixing things until everything compiled, so even though it is
large patch I feel ok(ish) with committing it.
If anyone has any concerns/etc, please email me and I will revert in 1 second.
Swift SVN r7604
Because union layout may interleave tag bits with payload data, we need to be able to efficiently inject and remove tag bits from an address-only union in-place. To do this, we'll model address-only union initialization by projecting out the data address (union_data_addr) and storing to it, then overlaying the tag bits (inject_union_addr). To dispatch and project out the data, we'll use a destructive_switch_union_addr instruction that clears any tag bits in-place necessary to give a valid data address.
Swift SVN r7589
The instruction represents constructing a loadable union given a case and the data for that case, which will let us emit union constructor functions in SIL instead of IRGen (rdar://problem/14773182).
Swift SVN r7558
