[clang][OpenMP] Implement isOpenMPExecutableDirective (#97089)

What is considered "executable" in clang differs slightly from the
OpenMP's "executable" category. In addition to the executable category,
subsidiary directives, and OMPD_error are considered executable.

Implement a function that performs that check.

Author: kparzysz

clang/include/clang/Basic/OpenMPKinds.h

@@ -368,6 +368,14 @@ bool needsTaskBasedThreadLimit(OpenMPDirectiveKind DKind);
 /// is restricted only to memory order clauses of "OMPC_acquire",
 /// "OMPC_relaxed" and "OMPC_seq_cst".
 bool checkFailClauseParameter(OpenMPClauseKind FailClauseParameter);
+
+/// Checks if the specified directive is considered as "executable". This
+/// combines the OpenMP categories of "executable" and "subsidiary", plus
+/// any other directives that should be treated as executable.
+/// \param DKind Specified directive.
+/// \return true - if the above condition is met for this directive
+/// otherwise - false.
+bool isOpenMPExecutableDirective(OpenMPDirectiveKind DKind);
 }
 
 #endif

clang/lib/Basic/OpenMPKinds.cpp

@@ -702,6 +702,13 @@ bool clang::needsTaskBasedThreadLimit(OpenMPDirectiveKind DKind) {
          DKind == OMPD_target_parallel_loop;
 }
 
+bool clang::isOpenMPExecutableDirective(OpenMPDirectiveKind DKind) {
+  if (DKind == OMPD_error)
+    return true;
+  Category Cat = getDirectiveCategory(DKind);
+  return Cat == Category::Executable || Cat == Category::Subsidiary;
+}
+
 void clang::getOpenMPCaptureRegions(
     SmallVectorImpl<OpenMPDirectiveKind> &CaptureRegions,
     OpenMPDirectiveKind DKind) {

clang/lib/Parse/ParseOpenMP.cpp

@@ -2397,10 +2397,8 @@ Parser::DeclGroupPtrTy Parser::ParseOpenMPDeclarativeDirectiveWithExtDecl(
 StmtResult Parser::ParseOpenMPExecutableDirective(
     ParsedStmtContext StmtCtx, OpenMPDirectiveKind DKind, SourceLocation Loc,
     bool ReadDirectiveWithinMetadirective) {
-  assert((DKind == OMPD_error ||
-          getDirectiveCategory(DKind) == Category::Executable ||
-          getDirectiveCategory(DKind) == Category::Subsidiary) &&
-         "Directive with an unexpected category");
+  assert(isOpenMPExecutableDirective(DKind) && "Unexpected directive category");
+
   bool HasAssociatedStatement = true;
   Association Assoc = getDirectiveAssociation(DKind);
 

clang/lib/Sema/SemaOpenMP.cpp

@@ -6357,6 +6357,8 @@ StmtResult SemaOpenMP::ActOnOpenMPExecutableDirective(
     OpenMPDirectiveKind CancelRegion, ArrayRef<OMPClause *> Clauses,
     Stmt *AStmt, SourceLocation StartLoc, SourceLocation EndLoc,
     OpenMPDirectiveKind PrevMappedDirective) {
+  assert(isOpenMPExecutableDirective(Kind) && "Unexpected directive category");
+
   StmtResult Res = StmtError();
   OpenMPBindClauseKind BindKind = OMPC_BIND_unknown;
   llvm::SmallVector<OMPClause *> ClausesWithoutBind;