[flang][driver] Add `-fdebug-dump-parsing-log`

This patch adds `-fdebug-dump-parsing-log` in the new driver. This option is
semantically identical to `-fdebug-instrumented-parse` in `f18` (the
former is added as an alias in `f18`).

As dumping the parsing log makes only sense for instrumented parses, we
set Fortran::parser::Options::instrumentedParse to `True` when
`-fdebug-dump-parsing-log` is used. This is consistent with `f18`.

To facilitate tweaking the configuration of the frontend based on the
action being requested, `setUpFrontendBasedOnAction` is introduced in
CompilerInvocation.cpp.

Differential Revision: https://reviews.llvm.org/D97457

1 files changed, 18 insertions, 0 deletions

diff --git a/flang/lib/Frontend/CompilerInvocation.cpp b/flang/lib/Frontend/CompilerInvocation.cpp
index 0dc7e7c..1764970 100644
--- a/flang/lib/Frontend/CompilerInvocation.cpp
+++ b/flang/lib/Frontend/CompilerInvocation.cpp
@@ -85,6 +85,15 @@ bool Fortran::frontend::ParseDiagnosticArgs(clang::DiagnosticOptions &opts,
   return true;
 }
 
+// Tweak the frontend configuration based on the frontend action
+static void setUpFrontendBasedOnAction(FrontendOptions &opts) {
+  assert(opts.programAction_ != Fortran::frontend::InvalidAction &&
+      "Fortran frontend action not set!");
+
+  if (opts.programAction_ == DebugDumpParsingLog)
+    opts.instrumentedParse_ = true;
+}
+
 static InputKind ParseFrontendArgs(FrontendOptions &opts,
     llvm::opt::ArgList &args, clang::DiagnosticsEngine &diags) {
 
@@ -125,6 +134,9 @@ static InputKind ParseFrontendArgs(FrontendOptions &opts,
     case clang::driver::options::OPT_fdebug_dump_provenance:
       opts.programAction_ = DebugDumpProvenance;
       break;
+    case clang::driver::options::OPT_fdebug_dump_parsing_log:
+      opts.programAction_ = DebugDumpParsingLog;
+      break;
     case clang::driver::options::OPT_fdebug_measure_parse_tree:
       opts.programAction_ = DebugMeasureParseTree;
       break;
@@ -264,6 +276,9 @@ static InputKind ParseFrontendArgs(FrontendOptions &opts,
           << arg->getAsString(args) << argValue;
     }
   }
+
+  setUpFrontendBasedOnAction(opts);
+
   return dashX;
 }
 
@@ -484,6 +499,9 @@ void CompilerInvocation::setFortranOpts() {
   // directories
   if (moduleDirJ.compare(".") != 0)
     fortranOptions.searchDirectories.emplace_back(moduleDirJ);
+
+  if (frontendOptions.instrumentedParse_)
+    fortranOptions.instrumentedParse = true;
 }
 
 void CompilerInvocation::setSemanticsOpts(