Recent changes to MLIR meant that Flang does not generate any debug line
This patch adds a pass that provides some foundation work with which
basic line table debug info can be generated. A walk is performed on
all the func ops in the module and they are decorated with a fusedLoc
op that contains the debug metadata for the subroutine along with
Alternatives include populating this info during lowering or during FIR
to LLVM Dialect conversion.
Note: Patches in future will add
-> more realistic debug info for types and other fields. -> driver flags to control generation of debug.