[OpenMP][WIP] Use ATTACH maps for array-sections/subscripts on pointers.

clang/include/clang/AST/OpenMPClause.h

@@ -5815,6 +5815,12 @@ class OMPClauseMappableExprCommon {
     ValueDecl *getAssociatedDeclaration() const {
       return AssociatedDeclaration;
     }
+
+    bool operator==(const MappableComponent &Other) const {
+      return AssociatedExpressionNonContiguousPr ==
+                 Other.AssociatedExpressionNonContiguousPr &&
+             AssociatedDeclaration == Other.AssociatedDeclaration;
+    }
   };
 
   // List of components of an expression. This first one is the whole
@@ -5828,6 +5834,13 @@ class OMPClauseMappableExprCommon {
   using MappableExprComponentLists = SmallVector<MappableExprComponentList, 8>;
   using MappableExprComponentListsRef = ArrayRef<MappableExprComponentList>;
 
+  // Hash function to allow usage as DenseMap keys.
+  friend llvm::hash_code hash_value(const MappableComponent &MC) {
+    return llvm::hash_combine(MC.getAssociatedExpression(),
+                              MC.getAssociatedDeclaration(),
+                              MC.isNonContiguous());
+  }
+
 protected:
   // Return the total number of elements in a list of component lists.
   static unsigned

clang/include/clang/Basic/OpenMPKinds.h

@@ -301,6 +301,14 @@ bool isOpenMPTargetExecutionDirective(OpenMPDirectiveKind DKind);
 /// otherwise - false.
 bool isOpenMPTargetDataManagementDirective(OpenMPDirectiveKind DKind);
 
+/// Checks if the specified directive is a map-entering target directive.
+/// \param DKind Specified directive.
+/// \return true - the directive is a map-entering target directive like
+/// 'omp target', 'omp target data', 'omp target enter data',
+/// 'omp target parallel', etc. (excludes 'omp target exit data', 'omp target
+/// update') otherwise - false.
+bool isOpenMPTargetMapEnteringDirective(OpenMPDirectiveKind DKind);
+
 /// Checks if the specified composite/combined directive constitutes a teams
 /// directive in the outermost nest.  For example
 /// 'omp teams distribute' or 'omp teams distribute parallel for'.

clang/lib/Basic/OpenMPKinds.cpp

@@ -650,6 +650,11 @@ bool clang::isOpenMPTargetDataManagementDirective(OpenMPDirectiveKind DKind) {
          DKind == OMPD_target_exit_data || DKind == OMPD_target_update;
 }
 
+bool clang::isOpenMPTargetMapEnteringDirective(OpenMPDirectiveKind DKind) {
+  return DKind == OMPD_target_data || DKind == OMPD_target_enter_data ||
+         isOpenMPTargetExecutionDirective(DKind);
+}
+
 bool clang::isOpenMPNestingTeamsDirective(OpenMPDirectiveKind DKind) {
   if (DKind == OMPD_teams)
     return true;