[OpenMP] Diagnose function name on the link clause

This patch is to add diagnose when a function name is
specified on the link clause. According to the  OpenMP
spec, only the list items that exclude the function 
name are allowed on the link clause.

Differential Revision: https://reviews.llvm.org/D40968

llvm-svn: 320521

clang/include/clang/Basic/DiagnosticSemaKinds.td

@@ -8710,6 +8710,8 @@ def err_omp_declare_target_to_and_link : Error<
 def warn_omp_not_in_target_context : Warning<
   "declaration is not declared in any declare target region">,
   InGroup<OpenMPTarget>;
+def err_omp_function_in_link_clause : Error<
+  "function name is not allowed in 'link' clause">;
 def err_omp_aligned_expected_array_or_ptr : Error<
   "argument of aligned clause should be array"
   "%select{ or pointer|, pointer, reference to array or reference to pointer}1"

clang/include/clang/Sema/Sema.h

@@ -8656,7 +8656,8 @@ public:
                                     OMPDeclareTargetDeclAttr::MapTypeTy MT,
                                     NamedDeclSetType &SameDirectiveDecls);
   /// Check declaration inside target region.
-  void checkDeclIsAllowedInOpenMPTarget(Expr *E, Decl *D);
+  void checkDeclIsAllowedInOpenMPTarget(Expr *E, Decl *D,
+                                        SourceLocation IdLoc = SourceLocation());
   /// Return true inside OpenMP declare target region.
   bool isInOpenMPDeclareTargetContext() const {
     return IsInOpenMPDeclareTargetContext;

clang/lib/Sema/SemaOpenMP.cpp

@@ -12600,7 +12600,7 @@ void Sema::ActOnOpenMPDeclareTargetName(Scope *CurScope,
       ND->addAttr(A);
       if (ASTMutationListener *ML = Context.getASTMutationListener())
         ML->DeclarationMarkedOpenMPDeclareTarget(ND, A);
-      checkDeclIsAllowedInOpenMPTarget(nullptr, ND);
+      checkDeclIsAllowedInOpenMPTarget(nullptr, ND, Id.getLoc());
     } else if (ND->getAttr<OMPDeclareTargetDeclAttr>()->getMapType() != MT) {
       Diag(Id.getLoc(), diag::err_omp_declare_target_to_and_link)
           << Id.getName();
@@ -12689,7 +12689,8 @@ static bool checkValueDeclInTarget(SourceLocation SL, SourceRange SR,
   return true;
 }
 
-void Sema::checkDeclIsAllowedInOpenMPTarget(Expr *E, Decl *D) {
+void Sema::checkDeclIsAllowedInOpenMPTarget(Expr *E, Decl *D,
+                                            SourceLocation IdLoc) {
   if (!D || D->isInvalidDecl())
     return;
   SourceRange SR = E ? E->getSourceRange() : D->getSourceRange();
@@ -12718,6 +12719,16 @@ void Sema::checkDeclIsAllowedInOpenMPTarget(Expr *E, Decl *D) {
       return;
     }
   }
+  if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
+    if (FD->hasAttr<OMPDeclareTargetDeclAttr>() &&
+        (FD->getAttr<OMPDeclareTargetDeclAttr>()->getMapType() ==
+         OMPDeclareTargetDeclAttr::MT_Link)) {
+      assert(IdLoc.isValid() && "Source location is expected");
+      Diag(IdLoc, diag::err_omp_function_in_link_clause);
+      Diag(FD->getLocation(), diag::note_defined_here) << FD;
+      return;
+    }
+  }
   if (!E) {
     // Checking declaration inside declare target region.
     if (!D->hasAttr<OMPDeclareTargetDeclAttr>() &&

clang/test/OpenMP/declare_target_ast_print.cpp

@@ -108,9 +108,7 @@ void f2() {
 // CHECK: #pragma omp end declare target
 
 int c1, c2, c3;
-void f3() {
+#pragma omp declare target link(c1) link(c2), link(c3)
-}
-#pragma omp declare target link(c1) link(c2), link(c3, f3)
 // CHECK: #pragma omp declare target link
 // CHECK: int c1;
 // CHECK: #pragma omp end declare target
@@ -120,9 +118,6 @@ void f3() {
 // CHECK: #pragma omp declare target link
 // CHECK: int c3;
 // CHECK: #pragma omp end declare target
-// CHECK: #pragma omp declare target link
-// CHECK: void f3()
-// CHECK: #pragma omp end declare target
 
 struct SSSt {
 #pragma omp declare target

clang/test/OpenMP/declare_target_messages.cpp

@@ -19,6 +19,10 @@ void f();
 
 void c(); // expected-warning {{declaration is not declared in any declare target region}}
 
+void func() {} // expected-note {{'func' defined here}}
+
+#pragma omp declare target link(func) // expected-error {{function name is not allowed in 'link' clause}}
+
 extern int b;
 
 struct NonT {