We can change llvm-dwp to emit DWARF64 version of the .debug_str_offsets
tables for .dwo files in a .dwp file. This allows the string table to
exceed 4GB without truncating string offsets into the .debug_str section
and losing data. llvm-dwp will append all strings to the .debug_str
section for a .dwo file, and if any of the new string offsets exceed
UINT32_MAX, it will upgrade the .debug_str_offsets table to a DWARF64
header and then each string offset in that table can now have a 64 bit
offset.
Fixed LLDB to be able to successfully load the 64 bit string tables in
.dwp files.
Fixed llvm-dwarfdump and LLVM DWARF parsing code to do the right thing
with DWARF64 string table headers.
ac6e48de40