This new TableGen backend, invoked with --print-detailed-records, prints all the details about the global variables, classes, and records in a TableGen file. It includes more details than the default backend.
The "TableGen Backend Developer's Guide" is updated to describe this new backend.
Add a function to the SourceMgr class to get a string with a source location formatted in the standard way.
clang-format: please reformat the code