[OPENMP50]Initial support for scan directive.

Addedi basic parsing/sema/serialization support for scan directive.

Author: alexey-bataev

clang/include/clang-c/Index.h

@@ -2578,7 +2578,11 @@ enum CXCursorKind {
    */
   CXCursor_OMPDepobjDirective             = 286,
 
-  CXCursor_LastStmt = CXCursor_OMPDepobjDirective,
+  /** OpenMP scan directive.
+   */
+  CXCursor_OMPScanDirective               = 287,
+
+  CXCursor_LastStmt = CXCursor_OMPScanDirective,
 
   /**
    * Cursor that represents the translation unit itself.

clang/include/clang/AST/RecursiveASTVisitor.h

@@ -2852,6 +2852,9 @@ DEF_TRAVERSE_STMT(OMPFlushDirective,
 DEF_TRAVERSE_STMT(OMPDepobjDirective,
                   { TRY_TO(TraverseOMPExecutableDirective(S)); })
 
+DEF_TRAVERSE_STMT(OMPScanDirective,
+                  { TRY_TO(TraverseOMPExecutableDirective(S)); })
+
 DEF_TRAVERSE_STMT(OMPOrderedDirective,
                   { TRY_TO(TraverseOMPExecutableDirective(S)); })
 

clang/include/clang/AST/StmtOpenMP.h

@@ -4688,6 +4688,63 @@ class OMPTargetTeamsDistributeSimdDirective final : public OMPLoopDirective {
   }
 };
 
+/// This represents '#pragma omp scan' directive.
+///
+/// \code
+/// #pragma omp scan inclusive(a)
+/// \endcode
+/// In this example directive '#pragma omp scan' has clause 'inclusive' with
+/// list item 'a'.
+class OMPScanDirective final : public OMPExecutableDirective {
+  friend class ASTStmtReader;
+  /// Build directive with the given start and end location.
+  ///
+  /// \param StartLoc Starting location of the directive kind.
+  /// \param EndLoc Ending location of the directive.
+  /// \param NumClauses Number of clauses.
+  ///
+  OMPScanDirective(SourceLocation StartLoc, SourceLocation EndLoc,
+                   unsigned NumClauses)
+      : OMPExecutableDirective(this, OMPScanDirectiveClass,
+                               llvm::omp::OMPD_scan, StartLoc, EndLoc,
+                               NumClauses, 0) {}
+
+  /// Build an empty directive.
+  ///
+  /// \param NumClauses Number of clauses.
+  ///
+  explicit OMPScanDirective(unsigned NumClauses)
+      : OMPExecutableDirective(this, OMPScanDirectiveClass,
+                               llvm::omp::OMPD_scan, SourceLocation(),
+                               SourceLocation(), NumClauses, 0) {}
+
+public:
+  /// Creates directive with a list of \a Clauses.
+  ///
+  /// \param C AST context.
+  /// \param StartLoc Starting location of the directive kind.
+  /// \param EndLoc Ending Location of the directive.
+  /// \param Clauses List of clauses (only single OMPFlushClause clause is
+  /// allowed).
+  ///
+  static OMPScanDirective *Create(const ASTContext &C, SourceLocation StartLoc,
+                                  SourceLocation EndLoc,
+                                  ArrayRef<OMPClause *> Clauses);
+
+  /// Creates an empty directive with the place for \a NumClauses
+  /// clauses.
+  ///
+  /// \param C AST context.
+  /// \param NumClauses Number of clauses.
+  ///
+  static OMPScanDirective *CreateEmpty(const ASTContext &C, unsigned NumClauses,
+                                       EmptyShell);
+
+  static bool classof(const Stmt *T) {
+    return T->getStmtClass() == OMPScanDirectiveClass;
+  }
+};
+
 } // end namespace clang
 
 #endif

clang/include/clang/Basic/DiagnosticSemaKinds.td

@@ -9823,9 +9823,10 @@ def err_omp_prohibited_region : Error<
   "%select{|; perhaps you forget to enclose 'omp %3' directive into a parallel region?|"
   "; perhaps you forget to enclose 'omp %3' directive into a for or a parallel for region with 'ordered' clause?|"
   "; perhaps you forget to enclose 'omp %3' directive into a target region?|"
-  "; perhaps you forget to enclose 'omp %3' directive into a teams region?}2">;
+  "; perhaps you forget to enclose 'omp %3' directive into a teams region?|"
+  "; perhaps you forget to enclose 'omp %3' directive into a for, simd, or for simd region?}2">;
 def err_omp_prohibited_region_simd : Error<
-  "OpenMP constructs may not be nested inside a simd region%select{| except for ordered simd, simd or atomic directive}0">;
+  "OpenMP constructs may not be nested inside a simd region%select{| except for ordered simd, simd, scan, or atomic directive}0">;
 def err_omp_prohibited_region_atomic : Error<
   "OpenMP constructs may not be nested inside an atomic region">;
 def err_omp_prohibited_region_critical_same_name : Error<
@@ -10016,7 +10017,7 @@ def warn_omp_nesting_simd : Warning<
   InGroup<SourceUsesOpenMP>;
 def err_omp_orphaned_device_directive : Error<
   "orphaned 'omp %0' directives are prohibited"
-  "; perhaps you forget to enclose the directive into a %select{|||target |teams }1region?">;
+  "; perhaps you forget to enclose the directive into a %select{|||target |teams|for, simd, or for simd }1region?">;
 def err_omp_reduction_non_addressable_expression : Error<
   "expected addressable reduction item for the task-based directives">;
 def err_omp_reduction_with_nogroup : Error<

clang/include/clang/Basic/StmtNodes.td

@@ -233,6 +233,7 @@ def OMPTaskwaitDirective : StmtNode<OMPExecutableDirective>;
 def OMPTaskgroupDirective : StmtNode<OMPExecutableDirective>;
 def OMPFlushDirective : StmtNode<OMPExecutableDirective>;
 def OMPDepobjDirective : StmtNode<OMPExecutableDirective>;
+def OMPScanDirective : StmtNode<OMPExecutableDirective>;
 def OMPOrderedDirective : StmtNode<OMPExecutableDirective>;
 def OMPAtomicDirective : StmtNode<OMPExecutableDirective>;
 def OMPTargetDirective : StmtNode<OMPExecutableDirective>;

clang/include/clang/Sema/Sema.h

@@ -10094,6 +10094,10 @@ class Sema final {
   StmtResult ActOnOpenMPDepobjDirective(ArrayRef<OMPClause *> Clauses,
                                         SourceLocation StartLoc,
                                         SourceLocation EndLoc);
+  /// Called on well-formed '\#pragma omp scan'.
+  StmtResult ActOnOpenMPScanDirective(ArrayRef<OMPClause *> Clauses,
+                                      SourceLocation StartLoc,
+                                      SourceLocation EndLoc);
   /// Called on well-formed '\#pragma omp ordered' after parsing of the
   /// associated statement.
   StmtResult ActOnOpenMPOrderedDirective(ArrayRef<OMPClause *> Clauses,

clang/include/clang/Serialization/ASTBitCodes.h

@@ -1826,6 +1826,7 @@ namespace serialization {
       STMT_OMP_TASKWAIT_DIRECTIVE,
       STMT_OMP_FLUSH_DIRECTIVE,
       STMT_OMP_DEPOBJ_DIRECTIVE,
+      STMT_OMP_SCAN_DIRECTIVE,
       STMT_OMP_ORDERED_DIRECTIVE,
       STMT_OMP_ATOMIC_DIRECTIVE,
       STMT_OMP_TARGET_DIRECTIVE,

clang/lib/AST/StmtOpenMP.cpp

@@ -781,6 +781,27 @@ OMPDepobjDirective *OMPDepobjDirective::CreateEmpty(const ASTContext &C,
   return new (Mem) OMPDepobjDirective(NumClauses);
 }
 
+OMPScanDirective *OMPScanDirective::Create(const ASTContext &C,
+                                           SourceLocation StartLoc,
+                                           SourceLocation EndLoc,
+                                           ArrayRef<OMPClause *> Clauses) {
+  unsigned Size = llvm::alignTo(sizeof(OMPScanDirective), alignof(OMPClause *));
+  void *Mem = C.Allocate(Size + sizeof(OMPClause *) * Clauses.size(),
+                         alignof(OMPScanDirective));
+  auto *Dir = new (Mem) OMPScanDirective(StartLoc, EndLoc, Clauses.size());
+  Dir->setClauses(Clauses);
+  return Dir;
+}
+
+OMPScanDirective *OMPScanDirective::CreateEmpty(const ASTContext &C,
+                                                unsigned NumClauses,
+                                                EmptyShell) {
+  unsigned Size = llvm::alignTo(sizeof(OMPScanDirective), alignof(OMPClause *));
+  void *Mem = C.Allocate(Size + sizeof(OMPClause *) * NumClauses,
+                         alignof(OMPScanDirective));
+  return new (Mem) OMPScanDirective(NumClauses);
+}
+
 OMPOrderedDirective *OMPOrderedDirective::Create(const ASTContext &C,
                                                  SourceLocation StartLoc,
                                                  SourceLocation EndLoc,

clang/lib/AST/StmtPrinter.cpp

@@ -758,6 +758,11 @@ void StmtPrinter::VisitOMPDepobjDirective(OMPDepobjDirective *Node) {
   PrintOMPExecutableDirective(Node);
 }
 
+void StmtPrinter::VisitOMPScanDirective(OMPScanDirective *Node) {
+  Indent() << "#pragma omp scan";
+  PrintOMPExecutableDirective(Node);
+}
+
 void StmtPrinter::VisitOMPOrderedDirective(OMPOrderedDirective *Node) {
   Indent() << "#pragma omp ordered";
   PrintOMPExecutableDirective(Node, Node->hasClausesOfKind<OMPDependClause>());

clang/lib/AST/StmtProfile.cpp

@@ -900,6 +900,10 @@ void StmtProfiler::VisitOMPDepobjDirective(const OMPDepobjDirective *S) {
   VisitOMPExecutableDirective(S);
 }
 
+void StmtProfiler::VisitOMPScanDirective(const OMPScanDirective *S) {
+  VisitOMPExecutableDirective(S);
+}
+
 void StmtProfiler::VisitOMPOrderedDirective(const OMPOrderedDirective *S) {
   VisitOMPExecutableDirective(S);
 }