Comment parsing: add CommentOptions to allow specifying custom comment block commands

Add an ability to specify custom documentation block comment commands via a new
class CommentOptions.  The intention is that this class will hold future
customizations for comment parsing, including defining documentation comments
with specific numbers of parameters, etc.

CommentOptions instance is a member of LangOptions.

CommentOptions is controlled by a new command-line parameter
-fcomment-block-commands=Foo,Bar,Baz.

llvm-svn: 175892

clang/lib/Frontend/CompilerInvocation.cpp

@@ -279,6 +279,10 @@ static bool ParseMigratorArgs(MigratorOptions &Opts, ArgList &Args) {
   return true;
 }
 
+static void ParseCommentArgs(CommentOptions &Opts, ArgList &Args) {
+  Opts.BlockCommandNames = Args.getAllArgValues(OPT_fcomment_block_commands);
+}
+
 static bool ParseCodeGenArgs(CodeGenOptions &Opts, ArgList &Args, InputKind IK,
                              DiagnosticsEngine &Diags) {
   using namespace options;
@@ -1522,6 +1526,7 @@ bool CompilerInvocation::CreateFromArgs(CompilerInvocation &Res,
   ParseDependencyOutputArgs(Res.getDependencyOutputOpts(), *Args);
   Success = ParseDiagnosticArgs(Res.getDiagnosticOpts(), *Args, &Diags)
             && Success;
+  ParseCommentArgs(Res.getLangOpts()->CommentOpts, *Args);
   ParseFileSystemArgs(Res.getFileSystemOpts(), *Args);
   // FIXME: We shouldn't have to pass the DashX option around here
   InputKind DashX = ParseFrontendArgs(Res.getFrontendOpts(), *Args, Diags);