- BlockDeclRefExprs always store VarDecls
- BDREs no longer store copy expressions
- BlockDecls now store a list of captured variables, information about
how they're captured, and a copy expression if necessary
With that in hand, change IR generation to use the captures data in
blocks instead of walking the block independently.
Additionally, optimize block layout by emitting fields in descending
alignment order, with a heuristic for filling in words when alignment
of the end of the block header is insufficient for the most aligned
field.
llvm-svn: 125005
derived-to-base cast that also casts away constness (one of the cases
for static_cast followed by const_cast) would be treated as a bit-cast
rather than a derived-to-base class, causing miscompiles and
heartburn.
Fixes <rdar://problem/8913298>.
llvm-svn: 124340