[flang][OpenMP] Use DirId() instead of DirName().v, NFC

flang/lib/Parser/openmp-parsers.cpp

@@ -1920,7 +1920,7 @@ struct OmpLoopConstructParser {
     auto loopItem{LoopNestParser{} || ompLoopConstruct};
 
     if (auto &&begin{OmpBeginDirectiveParser(dirs_).Parse(state)}) {
-      auto loopDir{begin->DirName().v};
+      auto loopDir{begin->DirId()};
       auto assoc{llvm::omp::getDirectiveAssociation(loopDir)};
       if (assoc == llvm::omp::Association::LoopNest) {
         if (auto &&item{attempt(loopItem).Parse(state)}) {

flang/lib/Semantics/check-omp-loop.cpp

@@ -271,7 +271,7 @@ void OmpStructureChecker::CheckNestedBlock(const parser::OpenMPLoopConstruct &x,
     } else if (parser::Unwrap<parser::DoConstruct>(stmt)) {
       ++nestedCount;
     } else if (auto *omp{parser::Unwrap<parser::OpenMPLoopConstruct>(stmt)}) {
-      if (!IsLoopTransforming(omp->BeginDir().DirName().v)) {
+      if (!IsLoopTransforming(omp->BeginDir().DirId())) {
         context_.Say(omp->source,
             "Only loop-transforming OpenMP constructs are allowed inside OpenMP loop constructs"_err_en_US);
       }
@@ -324,7 +324,7 @@ void OmpStructureChecker::CheckFullUnroll(
   // since it won't contain a loop.
   if (const parser::OpenMPLoopConstruct *nested{x.GetNestedConstruct()}) {
     auto &nestedSpec{nested->BeginDir()};
-    if (nestedSpec.DirName().v == llvm::omp::Directive::OMPD_unroll) {
+    if (nestedSpec.DirId() == llvm::omp::Directive::OMPD_unroll) {
       bool isPartial{
           llvm::any_of(nestedSpec.Clauses().v, [](const parser::OmpClause &c) {
             return c.Id() == llvm::omp::Clause::OMPC_partial;

flang/lib/Semantics/check-omp-structure.cpp

@@ -2800,7 +2800,7 @@ void OmpStructureChecker::Leave(const parser::OpenMPCancelConstruct &) {
 void OmpStructureChecker::Enter(const parser::OpenMPCriticalConstruct &x) {
   const parser::OmpBeginDirective &beginSpec{x.BeginDir()};
   const std::optional<parser::OmpEndDirective> &endSpec{x.EndDir()};
-  PushContextAndClauseSets(beginSpec.DirName().source, beginSpec.DirName().v);
+  PushContextAndClauseSets(beginSpec.DirName().source, beginSpec.DirId());
 
   const auto &block{std::get<parser::Block>(x.t)};
   CheckNoBranching(

flang/lib/Semantics/resolve-directives.cpp

@@ -2477,7 +2477,7 @@ bool OmpAttributeVisitor::Pre(const parser::OpenMPSectionConstruct &x) {
 
 bool OmpAttributeVisitor::Pre(const parser::OpenMPCriticalConstruct &x) {
   const parser::OmpBeginDirective &beginSpec{x.BeginDir()};
-  PushContext(beginSpec.DirName().source, beginSpec.DirName().v);
+  PushContext(beginSpec.DirName().source, beginSpec.DirId());
   GetContext().withinConstruct = true;
   return true;
 }

flang/lib/Semantics/rewrite-parse-tree.cpp

@@ -118,7 +118,7 @@ static bool ReturnsDataPointer(const Symbol &symbol) {
 }
 
 static bool LoopConstructIsSIMD(parser::OpenMPLoopConstruct *ompLoop) {
-  return llvm::omp::allSimdSet.test(ompLoop->BeginDir().DirName().v);
+  return llvm::omp::allSimdSet.test(ompLoop->BeginDir().DirId());
 }
 
 // Remove non-SIMD OpenMPConstructs once they are parsed.