round trip blockaddress through .ll and .bc files, so add a testcase. There are still a bunch of places in the optimizer and other places that need to be updated to work with these constructs, but at least the basics are in now. llvm-svn: 85377
llvm-svn: 85351
(assembler,asmprinter, bc reader+writer) and document it. Codegen currently aborts on it. llvm-svn: 85274
llvm-svn: 85258