This is a change that only affects Swift and is NFC for the language plugins on llvm.org. In Swift, we can have global variables with a location such as DW_OP_addr <addr> DW_OP_deref. The DWARF expression evaluator doesn't know how to apply a DW_OP_deref to a file address, but at the very end we convert the file address into a load address.
This patch moves the file->load address conversion to right after the result of the DW_OP_addr is pushed onto the stack so that a subsequent DW_OP_deref (and potentially other operations) can be interpreted.
rdar://problem/39767528 LLDB can't deal with dwarf expressions on global variables