[clang][OpenMP5.1] Initial parsing/sema for 'indirect' clause

Differential Revision: https://reviews.llvm.org/D116764

13 files changed, 218 insertions, 39 deletions

diff --git a/clang/include/clang/Basic/Attr.td b/clang/include/clang/Basic/Attr.td
index 10c5c7f1b879..b071ebb4d576 100644
--- a/clang/include/clang/Basic/Attr.td
+++ b/clang/include/clang/Basic/Attr.td
@@ -3686,6 +3686,8 @@ def OMPDeclareTargetDecl : InheritableAttr {
     EnumArgument<"DevType", "DevTypeTy",
                  [ "host", "nohost", "any" ],
                  [ "DT_Host", "DT_NoHost", "DT_Any" ]>,
+    ExprArgument<"IndirectExpr">,
+    BoolArgument<"Indirect">,
     UnsignedArgument<"Level">
   ];
   let AdditionalMembers = [{
diff --git a/clang/include/clang/Basic/DiagnosticParseKinds.td b/clang/include/clang/Basic/DiagnosticParseKinds.td
index 9dc036c03faa..193dff8b9c8f 100644
--- a/clang/include/clang/Basic/DiagnosticParseKinds.td
+++ b/clang/include/clang/Basic/DiagnosticParseKinds.td
@@ -1344,15 +1344,17 @@ def warn_omp_unknown_assumption_clause_without_args
 def note_omp_assumption_clause_continue_here
     : Note<"the ignored tokens spans until here">;
 def err_omp_declare_target_unexpected_clause: Error<
-  "unexpected '%0' clause, only %select{'device_type'|'to' or 'link'|'to', 'link' or 'device_type'}1 clauses expected">;
+  "unexpected '%0' clause, only %select{'device_type'|'to' or 'link'|'to', 'link' or 'device_type'|'device_type', 'indirect'|'to', 'link', 'device_type' or 'indirect'}1 clauses expected">;
 def err_omp_begin_declare_target_unexpected_implicit_to_clause: Error<
   "unexpected '(', only 'to', 'link' or 'device_type' clauses expected for 'begin declare target' directive">;
 def err_omp_declare_target_unexpected_clause_after_implicit_to: Error<
   "unexpected clause after an implicit 'to' clause">;
 def err_omp_declare_target_missing_to_or_link_clause: Error<
-  "expected at least one 'to' or 'link' clause">;
+  "expected at least one %select{'to' or 'link'|'to', 'link' or 'indirect'}0 clause">;
 def err_omp_declare_target_multiple : Error<
   "%0 appears multiple times in clauses on the same declare target directive">;
+def err_omp_declare_target_indirect_device_type: Error<
+  "only 'device_type(any)' clause is allowed with indirect clause">;
 def err_omp_expected_clause: Error<
   "expected at least one clause on '#pragma omp %0' directive">;
 def err_omp_mapper_illegal_identifier : Error<
diff --git a/clang/include/clang/Parse/Parser.h b/clang/include/clang/Parse/Parser.h
index a98ad78401f0..74935c890017 100644
--- a/clang/include/clang/Parse/Parser.h
+++ b/clang/include/clang/Parse/Parser.h
@@ -3316,6 +3316,11 @@ private:
   /// nullptr.
   ///
   OMPClause *ParseOpenMPSimpleClause(OpenMPClauseKind Kind, bool ParseOnly);
+  /// Parses indirect clause
+  /// \param ParseOnly true to skip the clause's semantic actions and return
+  // false;
+  bool ParseOpenMPIndirectClause(Sema::DeclareTargetContextInfo &DTCI,
+                                 bool ParseOnly);
   /// Parses clause with a single expression and an additional argument
   /// of a kind \a Kind.
   ///
diff --git a/clang/include/clang/Sema/Sema.h b/clang/include/clang/Sema/Sema.h
index 9b6d9d20ca43..f1e90356c836 100644
--- a/clang/include/clang/Sema/Sema.h
+++ b/clang/include/clang/Sema/Sema.h
@@ -10333,6 +10333,9 @@ private:
     /// The directive kind, `begin declare target` or `declare target`.
     OpenMPDirectiveKind Kind;
 
+    /// The directive with indirect clause.
+    Optional<Expr *> Indirect;
+
     /// The directive location.
     SourceLocation Loc;
 
@@ -10639,7 +10642,7 @@ public:
   /// Called on correct id-expression from the '#pragma omp declare target'.
   void ActOnOpenMPDeclareTargetName(NamedDecl *ND, SourceLocation Loc,
                                     OMPDeclareTargetDeclAttr::MapTypeTy MT,
-                                    OMPDeclareTargetDeclAttr::DevTypeTy DT);
+                                    DeclareTargetContextInfo &DTCI);
 
   /// Check declaration inside target region.
   void
diff --git a/clang/lib/AST/AttrImpl.cpp b/clang/lib/AST/AttrImpl.cpp
index c2f13cf63830..7b8acfcd92be 100644
--- a/clang/lib/AST/AttrImpl.cpp
+++ b/clang/lib/AST/AttrImpl.cpp
@@ -139,6 +139,13 @@ void OMPDeclareTargetDeclAttr::printPrettyPragma(
     OS << " device_type(" << ConvertDevTypeTyToStr(getDevType()) << ")";
   if (getMapType() != MT_To)
     OS << ' ' << ConvertMapTypeTyToStr(getMapType());
+  if (Expr *E = getIndirectExpr()) {
+    OS << " indirect(";
+    E->printPretty(OS, nullptr, Policy);
+    OS << ")";
+  } else if (getIndirect()) {
+    OS << " indirect";
+  }
 }
 
 llvm::Optional<OMPDeclareTargetDeclAttr *>
diff --git a/clang/lib/CodeGen/CGStmtOpenMP.cpp b/clang/lib/CodeGen/CGStmtOpenMP.cpp
index b340e0505a78..11af2812a411 100644
--- a/clang/lib/CodeGen/CGStmtOpenMP.cpp
+++ b/clang/lib/CodeGen/CGStmtOpenMP.cpp
@@ -6049,6 +6049,7 @@ static void emitOMPAtomicExpr(CodeGenFunction &CGF, OpenMPClauseKind Kind,
   case OMPC_inbranch:
   case OMPC_notinbranch:
   case OMPC_link:
+  case OMPC_indirect:
   case OMPC_use:
   case OMPC_novariants:
   case OMPC_nocontext:
diff --git a/clang/lib/Parse/ParseOpenMP.cpp b/clang/lib/Parse/ParseOpenMP.cpp
index 0264d385610a..0089da741b59 100644
--- a/clang/lib/Parse/ParseOpenMP.cpp
+++ b/clang/lib/Parse/ParseOpenMP.cpp
@@ -1814,38 +1814,55 @@ parseOpenMPSimpleClause(Parser &P, OpenMPClauseKind Kind) {
 void Parser::ParseOMPDeclareTargetClauses(
     Sema::DeclareTargetContextInfo &DTCI) {
   SourceLocation DeviceTypeLoc;
-  bool RequiresToOrLinkClause = false;
-  bool HasToOrLinkClause = false;
+  bool RequiresToOrLinkOrIndirectClause = false;
+  bool HasToOrLinkOrIndirectClause = false;
   while (Tok.isNot(tok::annot_pragma_openmp_end)) {
     OMPDeclareTargetDeclAttr::MapTypeTy MT = OMPDeclareTargetDeclAttr::MT_To;
     bool HasIdentifier = Tok.is(tok::identifier);
     if (HasIdentifier) {
       // If we see any clause we need a to or link clause.
-      RequiresToOrLinkClause = true;
+      RequiresToOrLinkOrIndirectClause = true;
       IdentifierInfo *II = Tok.getIdentifierInfo();
       StringRef ClauseName = II->getName();
       bool IsDeviceTypeClause =
           getLangOpts().OpenMP >= 50 &&
           getOpenMPClauseKind(ClauseName) == OMPC_device_type;
 
+      bool IsIndirectClause = getLangOpts().OpenMP >= 51 &&
+                              getOpenMPClauseKind(ClauseName) == OMPC_indirect;
+      if (DTCI.Indirect.hasValue() && IsIndirectClause) {
+        Diag(Tok, diag::err_omp_more_one_clause)
+            << getOpenMPDirectiveName(OMPD_declare_target)
+            << getOpenMPClauseName(OMPC_indirect) << 0;
+        break;
+      }
       bool IsToOrLinkClause =
           OMPDeclareTargetDeclAttr::ConvertStrToMapTypeTy(ClauseName, MT);
       assert((!IsDeviceTypeClause || !IsToOrLinkClause) && "Cannot be both!");
 
-      if (!IsDeviceTypeClause && DTCI.Kind == OMPD_begin_declare_target) {
+      if (!IsDeviceTypeClause && !IsIndirectClause &&
+          DTCI.Kind == OMPD_begin_declare_target) {
         Diag(Tok, diag::err_omp_declare_target_unexpected_clause)
-            << ClauseName << 0;
+            << ClauseName << (getLangOpts().OpenMP >= 51 ? 3 : 0);
         break;
       }
-      if (!IsDeviceTypeClause && !IsToOrLinkClause) {
+      if (!IsDeviceTypeClause && !IsToOrLinkClause && !IsIndirectClause) {
         Diag(Tok, diag::err_omp_declare_target_unexpected_clause)
-            << ClauseName << (getLangOpts().OpenMP >= 50 ? 2 : 1);
+            << ClauseName
+            << (getLangOpts().OpenMP >= 51   ? 4
+                : getLangOpts().OpenMP >= 50 ? 2
+                                             : 1);
         break;
       }
 
-      if (IsToOrLinkClause)
-        HasToOrLinkClause = true;
+      if (IsToOrLinkClause || IsIndirectClause)
+        HasToOrLinkOrIndirectClause = true;
 
+      if (IsIndirectClause) {
+        if (!ParseOpenMPIndirectClause(DTCI, /*ParseOnly*/ false))
+          break;
+        continue;
+      }
       // Parse 'device_type' clause and go to next clause if any.
       if (IsDeviceTypeClause) {
         Optional<SimpleClauseData> DevTypeData =
@@ -1911,10 +1928,14 @@ void Parser::ParseOMPDeclareTargetClauses(
       ConsumeToken();
   }
 
+  if (DTCI.Indirect.hasValue() && DTCI.DT != OMPDeclareTargetDeclAttr::DT_Any)
+    Diag(DeviceTypeLoc, diag::err_omp_declare_target_indirect_device_type);
+
   // For declare target require at least 'to' or 'link' to be present.
-  if (DTCI.Kind == OMPD_declare_target && RequiresToOrLinkClause &&
-      !HasToOrLinkClause)
-    Diag(DTCI.Loc, diag::err_omp_declare_target_missing_to_or_link_clause);
+  if (DTCI.Kind == OMPD_declare_target && RequiresToOrLinkOrIndirectClause &&
+      !HasToOrLinkOrIndirectClause)
+    Diag(DTCI.Loc, diag::err_omp_declare_target_missing_to_or_link_clause)
+        << (getLangOpts().OpenMP >= 51 ? 1 : 0);
 
   SkipUntil(tok::annot_pragma_openmp_end, StopBeforeMatch);
 }
@@ -2283,11 +2304,12 @@ Parser::DeclGroupPtrTy Parser::ParseOpenMPDeclarativeDirectiveWithExtDecl(
   case OMPD_declare_target: {
     SourceLocation DTLoc = ConsumeAnyToken();
     bool HasClauses = Tok.isNot(tok::annot_pragma_openmp_end);
-    bool HasImplicitMappings =
-        DKind == OMPD_begin_declare_target || !HasClauses;
     Sema::DeclareTargetContextInfo DTCI(DKind, DTLoc);
     if (HasClauses)
       ParseOMPDeclareTargetClauses(DTCI);
+    bool HasImplicitMappings =
+        DKind == OMPD_begin_declare_target || !HasClauses ||
+        (DTCI.ExplicitlyMapped.empty() && DTCI.Indirect.hasValue());
 
     // Skip the last annot_pragma_openmp_end.
     ConsumeAnyToken();
@@ -3384,6 +3406,47 @@ OMPClause *Parser::ParseOpenMPSingleExprClause(OpenMPClauseKind Kind,
   return Actions.ActOnOpenMPSingleExprClause(Kind, Val.get(), Loc, LLoc, RLoc);
 }
 
+/// Parse indirect clause for '#pragma omp declare target' directive.
+///  'indirect' '[' '(' invoked-by-fptr ')' ']'
+/// where invoked-by-fptr is a constant boolean expression that evaluates to
+/// true or false at compile time.
+bool Parser::ParseOpenMPIndirectClause(Sema::DeclareTargetContextInfo &DTCI,
+                                       bool ParseOnly) {
+  SourceLocation Loc = ConsumeToken();
+  SourceLocation RLoc;
+
+  if (Tok.isNot(tok::l_paren)) {
+    if (ParseOnly)
+      return false;
+    DTCI.Indirect = nullptr;
+    return true;
+  }
+
+  ExprResult Val =
+      ParseOpenMPParensExpr(getOpenMPClauseName(OMPC_indirect), RLoc);
+  if (Val.isInvalid())
+    return false;
+
+  if (ParseOnly)
+    return false;
+
+  if (!Val.get()->isValueDependent() && !Val.get()->isTypeDependent() &&
+      !Val.get()->isInstantiationDependent() &&
+      !Val.get()->containsUnexpandedParameterPack()) {
+    ExprResult Ret = Actions.CheckBooleanCondition(Loc, Val.get());
+    if (Ret.isInvalid())
+      return false;
+    llvm::APSInt Result;
+    Ret = Actions.VerifyIntegerConstantExpression(Val.get(), &Result,
+                                                  Sema::AllowFold);
+    if (Ret.isInvalid())
+      return false;
+    DTCI.Indirect = Val.get();
+    return true;
+  }
+  return false;
+}
+
 /// Parsing of OpenMP clauses that use an interop-var.
 ///
 /// init-clause:
diff --git a/clang/lib/Sema/SemaOpenMP.cpp b/clang/lib/Sema/SemaOpenMP.cpp
index b97d9d90f6ca..20b090faaf4c 100644
--- a/clang/lib/Sema/SemaOpenMP.cpp
+++ b/clang/lib/Sema/SemaOpenMP.cpp
@@ -20762,8 +20762,7 @@ Sema::ActOnOpenMPEndDeclareTargetDirective() {
 void Sema::ActOnFinishedOpenMPDeclareTargetContext(
     DeclareTargetContextInfo &DTCI) {
   for (auto &It : DTCI.ExplicitlyMapped)
-    ActOnOpenMPDeclareTargetName(It.first, It.second.Loc, It.second.MT,
-                                 DTCI.DT);
+    ActOnOpenMPDeclareTargetName(It.first, It.second.Loc, It.second.MT, DTCI);
 }
 
 NamedDecl *Sema::lookupOpenMPDeclareTargetName(Scope *CurScope,
@@ -20800,9 +20799,9 @@ NamedDecl *Sema::lookupOpenMPDeclareTargetName(Scope *CurScope,
   return ND;
 }
 
-void Sema::ActOnOpenMPDeclareTargetName(
-    NamedDecl *ND, SourceLocation Loc, OMPDeclareTargetDeclAttr::MapTypeTy MT,
-    OMPDeclareTargetDeclAttr::DevTypeTy DT) {
+void Sema::ActOnOpenMPDeclareTargetName(NamedDecl *ND, SourceLocation Loc,
+                                        OMPDeclareTargetDeclAttr::MapTypeTy MT,
+                                        DeclareTargetContextInfo &DTCI) {
   assert((isa<VarDecl>(ND) || isa<FunctionDecl>(ND) ||
           isa<FunctionTemplateDecl>(ND)) &&
          "Expected variable, function or function template.");
@@ -20819,10 +20818,10 @@ void Sema::ActOnOpenMPDeclareTargetName(
   auto *VD = cast<ValueDecl>(ND);
   llvm::Optional<OMPDeclareTargetDeclAttr *> ActiveAttr =
       OMPDeclareTargetDeclAttr::getActiveAttr(VD);
-  if (ActiveAttr.hasValue() && ActiveAttr.getValue()->getDevType() != DT &&
+  if (ActiveAttr.hasValue() && ActiveAttr.getValue()->getDevType() != DTCI.DT &&
       ActiveAttr.getValue()->getLevel() == Level) {
     Diag(Loc, diag::err_omp_device_type_mismatch)
-        << OMPDeclareTargetDeclAttr::ConvertDevTypeTyToStr(DT)
+        << OMPDeclareTargetDeclAttr::ConvertDevTypeTyToStr(DTCI.DT)
         << OMPDeclareTargetDeclAttr::ConvertDevTypeTyToStr(
                ActiveAttr.getValue()->getDevType());
     return;
@@ -20836,8 +20835,16 @@ void Sema::ActOnOpenMPDeclareTargetName(
   if (ActiveAttr.hasValue() && ActiveAttr.getValue()->getLevel() == Level)
     return;
 
-  auto *A = OMPDeclareTargetDeclAttr::CreateImplicit(Context, MT, DT, Level,
-                                                     SourceRange(Loc, Loc));
+  Expr *IndirectE = nullptr;
+  bool IsIndirect = false;
+  if (DTCI.Indirect.hasValue()) {
+    IndirectE = DTCI.Indirect.getValue();
+    if (!IndirectE)
+      IsIndirect = true;
+  }
+  auto *A = OMPDeclareTargetDeclAttr::CreateImplicit(
+      Context, MT, DTCI.DT, IndirectE, IsIndirect, Level,
+      SourceRange(Loc, Loc));
   ND->addAttr(A);
   if (ASTMutationListener *ML = Context.getASTMutationListener())
     ML->DeclarationMarkedOpenMPDeclareTarget(ND, A);
@@ -20928,9 +20935,16 @@ void Sema::checkDeclIsAllowedInOpenMPTarget(Expr *E, Decl *D,
         if (ActiveAttr.hasValue() && ActiveAttr.getValue()->getLevel() >= Level)
           return;
         DeclareTargetContextInfo &DTCI = DeclareTargetNesting.back();
+        Expr *IndirectE = nullptr;
+        bool IsIndirect = false;
+        if (DTCI.Indirect.hasValue()) {
+          IndirectE = DTCI.Indirect.getValue();
+          if (!IndirectE)
+            IsIndirect = true;
+        }
         auto *A = OMPDeclareTargetDeclAttr::CreateImplicit(
-            Context, OMPDeclareTargetDeclAttr::MT_To, DTCI.DT, Level,
-            SourceRange(DTCI.Loc, DTCI.Loc));
+            Context, OMPDeclareTargetDeclAttr::MT_To, DTCI.DT, IndirectE,
+            IsIndirect, Level, SourceRange(DTCI.Loc, DTCI.Loc));
         D->addAttr(A);
         if (ASTMutationListener *ML = Context.getASTMutationListener())
           ML->DeclarationMarkedOpenMPDeclareTarget(D, A);
diff --git a/clang/lib/Serialization/ASTReaderDecl.cpp b/clang/lib/Serialization/ASTReaderDecl.cpp
index 2144befcdb14..310bbc0f3cbb 100644
--- a/clang/lib/Serialization/ASTReaderDecl.cpp
+++ b/clang/lib/Serialization/ASTReaderDecl.cpp
@@ -4781,10 +4781,12 @@ void ASTDeclReader::UpdateDecl(Decl *D,
     case UPD_DECL_MARKED_OPENMP_DECLARETARGET: {
       auto MapType = Record.readEnum<OMPDeclareTargetDeclAttr::MapTypeTy>();
       auto DevType = Record.readEnum<OMPDeclareTargetDeclAttr::DevTypeTy>();
+      Expr *IndirectE = Record.readExpr();
+      bool Indirect = Record.readBool();
       unsigned Level = Record.readInt();
       D->addAttr(OMPDeclareTargetDeclAttr::CreateImplicit(
-          Reader.getContext(), MapType, DevType, Level, readSourceRange(),
-          AttributeCommonInfo::AS_Pragma));
+          Reader.getContext(), MapType, DevType, IndirectE, Indirect, Level,
+          readSourceRange(), AttributeCommonInfo::AS_Pragma));
       break;
     }
 
diff --git a/clang/test/OpenMP/declare_target_ast_print.cpp b/clang/test/OpenMP/declare_target_ast_print.cpp
index dbd0b923a7d6..2dd45bbc7948 100644
--- a/clang/test/OpenMP/declare_target_ast_print.cpp
+++ b/clang/test/OpenMP/declare_target_ast_print.cpp
@@ -3,8 +3,11 @@
 // RUN: %clang_cc1 -fopenmp -std=c++11 -include-pch %t -fsyntax-only -I %S/Inputs -verify %s -ast-print | FileCheck %s
 
 // RUN: %clang_cc1 -verify -fopenmp -I %S/Inputs -ast-print %s | FileCheck %s --check-prefix=CHECK --check-prefix=OMP50
+// RUN: %clang_cc1 -verify -fopenmp -fopenmp-version=51 -I %S/Inputs -ast-print %s | FileCheck %s --check-prefix=CHECK --check-prefix=OMP51
 // RUN: %clang_cc1 -fopenmp -x c++ -std=c++11 -I %S/Inputs -emit-pch -o %t %s
 // RUN: %clang_cc1 -fopenmp -std=c++11 -include-pch %t -fsyntax-only -I %S/Inputs -verify %s -ast-print | FileCheck %s --check-prefix=CHECK --check-prefix=OMP50
+// RUN: %clang_cc1 -fopenmp -fopenmp-version=51 -x c++ -std=c++11 -I %S/Inputs -emit-pch -o %t %s
+// RUN: %clang_cc1 -fopenmp -fopenmp-version=51 -std=c++11 -include-pch %t -fsyntax-only -I %S/Inputs -verify %s -ast-print | FileCheck %s --check-prefix=CHECK --check-prefix=OMP51
 
 // RUN: %clang_cc1 -verify -fopenmp-simd -I %S/Inputs -ast-print %s | FileCheck %s
 // RUN: %clang_cc1 -fopenmp-simd -x c++ -std=c++11 -I %S/Inputs -emit-pch -o %t %s
@@ -32,6 +35,48 @@ void bazz();
 // OMP50: #pragma omp end declare target{{$}}
 #endif // _OPENMP
 
+#if _OPENMP == 202011
+extern "C" {
+void boo_c() {}
+#pragma omp declare target to(boo_c) indirect
+// OMP51: #pragma omp declare target indirect
+// OMP51: void boo_c() {
+// OMP51: }
+// OMP51: #pragma omp end declare target
+#pragma omp declare target indirect
+void yoo(){}
+#pragma omp end declare target
+// OMP51: #pragma omp declare target indirect
+// OMP51: void yoo() {
+// OMP51: }
+// OMP51: #pragma omp end declare target
+}
+extern "C++" {
+void boo_cpp() {}
+#pragma omp declare target to(boo_cpp) indirect
+// OMP51: #pragma omp declare target indirect
+// OMP51: void boo_cpp() {
+// OMP51: }
+// OMP51: #pragma omp end declare target
+
+constexpr bool f() {return false;}
+#pragma omp begin declare target indirect(f())
+void zoo() {}
+void xoo();
+#pragma omp end declare target
+#pragma omp declare target to(zoo) indirect(false)
+// OMP51: #pragma omp declare target indirect(f())
+// OMP51: #pragma omp declare target indirect(false)
+// OMP51: void zoo() {
+// OMP51: }
+// OMP51: #pragma omp end declare target
+// OMP51: #pragma omp declare target indirect(f())
+// OMP51: void xoo();
+// OMP51: #pragma omp end declare target
+
+}
+#endif // _OPENMP
+
 int out_decl_target = 0;
 #pragma omp declare target (out_decl_target)
 
diff --git a/clang/test/OpenMP/declare_target_messages.cpp b/clang/test/OpenMP/declare_target_messages.cpp
index 1f608e927421..31185881e192 100644
--- a/clang/test/OpenMP/declare_target_messages.cpp
+++ b/clang/test/OpenMP/declare_target_messages.cpp
@@ -5,11 +5,13 @@
 // RUN: %clang_cc1 -triple x86_64-apple-macos10.7.0 -verify=expected,omp5,host5 -fopenmp-simd -fopenmp-targets=x86_64-apple-macos10.7.0 -fnoopenmp-use-tls -ferror-limit 100 -o - %s
 // RUN: %clang_cc1 -triple x86_64-apple-macos10.7.0 -verify=expected,omp5,host5 -fopenmp-simd -fopenmp-is-device -fopenmp-targets=x86_64-apple-macos10.7.0 -fnoopenmp-use-tls -ferror-limit 100 -o - %s
 // RUN: %clang_cc1 -triple x86_64-apple-macos10.7.0 -verify=expected,omp45 -fopenmp-version=45 -fopenmp-simd -fnoopenmp-use-tls -ferror-limit 100 -o - %s
+// RUN: %clang_cc1 -triple x86_64-apple-macos10.7.0 -verify=expected,omp51 -fopenmp -fopenmp-version=51 -fnoopenmp-use-tls -ferror-limit 100 -o - %s
+// RUN: %clang_cc1 -triple x86_64-apple-macos10.7.0 -verify=expected,omp51 -fopenmp-version=51 -fopenmp-simd -fnoopenmp-use-tls -ferror-limit 100 -o - %s
 
 // RUN: %clang_cc1 -triple x86_64-apple-macos10.7.0 -verify=expected,omp5 -fopenmp -fnoopenmp-use-tls -ferror-limit 100 -o - %s
 #pragma omp end declare target // expected-error {{unexpected OpenMP directive '#pragma omp end declare target'}}
 
-int a, b, z; // omp5-error {{variable captured in declare target region must appear in a to clause}}
+int a, b, z; // omp5-error {{variable captured in declare target region must appear in a to clause}} // omp51-error {{variable captured in declare target region must appear in a to clause}}
 __thread int t; // expected-note {{defined as threadprivate or thread local}}
 
 #pragma omp declare target . // expected-error {{expected '(' after 'declare target'}}
@@ -18,7 +20,7 @@ __thread int t; // expected-note {{defined as threadprivate or thread local}}
 void f();
 #pragma omp end declare target shared(a) // expected-warning {{extra tokens at the end of '#pragma omp end declare target' are ignored}}
 
-#pragma omp declare target map(a) // expected-error {{expected at least one 'to' or 'link' clause}} omp45-error {{unexpected 'map' clause, only 'to' or 'link' clauses expected}} omp5-error {{unexpected 'map' clause, only 'to', 'link' or 'device_type' clauses expected}}
+#pragma omp declare target map(a) // omp45-error {{expected at least one 'to' or 'link' clause}} omp5-error {{expected at least one 'to' or 'link' clause}} omp51-error {{expected at least one 'to', 'link' or 'indirect' clause}} omp45-error {{unexpected 'map' clause, only 'to' or 'link' clauses expected}} omp5-error {{unexpected 'map' clause, only 'to', 'link' or 'device_type' clauses expected}} omp51-error {{unexpected 'map' clause, only 'to', 'link', 'device_type' or 'indirect' clauses expected}}
 
 #pragma omp declare target to(foo1) // expected-error {{use of undeclared identifier 'foo1'}}
 
@@ -27,17 +29,46 @@ void f();
 #pragma omp declare target to(f) device_type(host) // omp45-error {{unexpected 'device_type' clause, only 'to' or 'link' clauses expected}} dev5-note {{marked as 'device_type(host)' here}}
 
 void q();
-#pragma omp declare target to(q) device_type(any) device_type(any) device_type(host) // omp45-error {{unexpected 'device_type' clause, only 'to' or 'link' clauses expected}} omp5-warning {{more than one 'device_type' clause is specified}}
+#pragma omp declare target to(q) device_type(any) device_type(any) device_type(host) // omp45-error {{unexpected 'device_type' clause, only 'to' or 'link' clauses expected}} omp5-warning {{more than one 'device_type' clause is specified}} // omp51-warning {{more than one 'device_type' clause is specified}}
+
+#if _OPENMP == 202011
+// omp51-error@+1 {{directive '#pragma omp declare target' cannot contain more than one 'indirect' clause}}
+#pragma omp declare target to(q) indirect(true) indirect(false)
+
+int xxx; //expected-note {{declared here}}
+// omp51-error@+2 {{expression is not an integral constant expression}}
+// omp51-note@+1 {{read of non-const variable 'xxx' is not allowed in a constant expression}}
+#pragma omp declare target to(q) indirect(xxx)
+
+constexpr bool fz() {return true;}
+// omp51-error@+1 {{unexpected 'to' clause, only 'device_type', 'indirect' clauses expected}}
+#pragma omp begin declare target to(q) indirect(fz()) device_type(nohost)
+#pragma omp end declare target
+
+// omp51-error@+1 {{unexpected 'to' clause, only 'device_type', 'indirect' clauses expected}}
+#pragma omp begin declare target indirect to(xxx)
+void bar();
+#pragma omp end declare target
+
+// omp51-error@+2 {{unexpected 'tofrom' clause, only 'to', 'link', 'device_type' or 'indirect' clauses expected}}
+// omp51-error@+1 {{expected at least one 'to', 'link' or 'indirect' clause}}
+#pragma omp declare target tofrom(xxx)
+
+// omp51-error@+1 {{only 'device_type(any)' clause is allowed with indirect clause}}
+#pragma omp begin declare target device_type(host) indirect
+void bar();
+#pragma omp end declare target
+#endif  // _OPENMP
 
 void c();
 
 void func() {} // expected-note {{'func' defined here}}
 
-#pragma omp declare target link(func) allocate(a) // expected-error {{function name is not allowed in 'link' clause}} omp45-error {{unexpected 'allocate' clause, only 'to' or 'link' clauses expected}} omp5-error {{unexpected 'allocate' clause, only 'to', 'link' or 'device_type' clauses expected}}
+#pragma omp declare target link(func) allocate(a) // expected-error {{function name is not allowed in 'link' clause}} omp45-error {{unexpected 'allocate' clause, only 'to' or 'link' clauses expected}} omp5-error {{unexpected 'allocate' clause, only 'to', 'link' or 'device_type' clauses expected}} omp51-error {{unexpected 'allocate' clause, only 'to', 'link', 'device_type' or 'indirect' clauses expected}}
 
 void bar();
 void baz() {bar();}
-#pragma omp declare target(bar) // omp5-warning {{declaration marked as declare target after first use, it may lead to incorrect results}}
+#pragma omp declare target(bar) // omp5-warning {{declaration marked as declare target after first use, it may lead to incorrect results}} // omp51-warning {{declaration marked as declare target after first use, it may lead to incorrect results}}
 
 extern int b;
 
@@ -128,7 +159,7 @@ void foo(int p) {
 }
 #pragma omp declare target
 void foo1() {
-  [&](){ (void)(b+z);}(); // omp5-note {{variable 'z' is captured here}}
+  [&](){ (void)(b+z);}(); // omp5-note {{variable 'z' is captured here}} //omp51-note {{variable 'z' is captured here}}
 }
 #pragma omp end declare target
 
@@ -194,8 +225,8 @@ void any8() {any2();}
 
 int MultiDevTy;
 #pragma omp declare target to(MultiDevTy) device_type(any)    // omp45-error {{unexpected 'device_type' clause, only 'to' or 'link' clauses expected}}
-#pragma omp declare target to(MultiDevTy) device_type(host)   // omp45-error {{unexpected 'device_type' clause, only 'to' or 'link' clauses expected}} omp5-error {{'device_type(host)' does not match previously specified 'device_type(any)' for the same declaration}}
-#pragma omp declare target to(MultiDevTy) device_type(nohost) // omp45-error {{unexpected 'device_type' clause, only 'to' or 'link' clauses expected}} omp5-error {{'device_type(nohost)' does not match previously specified 'device_type(any)' for the same declaration}}
+#pragma omp declare target to(MultiDevTy) device_type(host)   // omp45-error {{unexpected 'device_type' clause, only 'to' or 'link' clauses expected}} omp5-error {{'device_type(host)' does not match previously specified 'device_type(any)' for the same declaration}} omp51-error {{'device_type(host)' does not match previously specified 'device_type(any)' for the same declaration}}
+#pragma omp declare target to(MultiDevTy) device_type(nohost) // omp45-error {{unexpected 'device_type' clause, only 'to' or 'link' clauses expected}} omp5-error {{'device_type(nohost)' does not match previously specified 'device_type(any)' for the same declaration}} // omp51-error {{'device_type(nohost)' does not match previously specified 'device_type(any)' for the same declaration}}
 
 // TODO: Issue an error message error {{expected '#pragma omp end declare target'}} note {{to match this '#pragma omp declare target'}}
 #pragma omp declare target
diff --git a/flang/lib/Semantics/check-omp-structure.cpp b/flang/lib/Semantics/check-omp-structure.cpp
index db7dd2e9670f..df66a42dede5 100644
--- a/flang/lib/Semantics/check-omp-structure.cpp
+++ b/flang/lib/Semantics/check-omp-structure.cpp
@@ -1528,6 +1528,7 @@ CHECK_SIMPLE_CLAUSE(Threads, OMPC_threads)
 CHECK_SIMPLE_CLAUSE(Inbranch, OMPC_inbranch)
 CHECK_SIMPLE_CLAUSE(IsDevicePtr, OMPC_is_device_ptr)
 CHECK_SIMPLE_CLAUSE(Link, OMPC_link)
+CHECK_SIMPLE_CLAUSE(Indirect, OMPC_indirect)
 CHECK_SIMPLE_CLAUSE(Mergeable, OMPC_mergeable)
 CHECK_SIMPLE_CLAUSE(Nogroup, OMPC_nogroup)
 CHECK_SIMPLE_CLAUSE(Notinbranch, OMPC_notinbranch)
diff --git a/llvm/include/llvm/Frontend/OpenMP/OMP.td b/llvm/include/llvm/Frontend/OpenMP/OMP.td
index 18d577dff497..c5abb16dd9e5 100644
--- a/llvm/include/llvm/Frontend/OpenMP/OMP.td
+++ b/llvm/include/llvm/Frontend/OpenMP/OMP.td
@@ -358,6 +358,7 @@ def OMPC_Unknown : Clause<"unknown"> {
 def OMPC_Link : Clause<"link"> {
   let flangClass = "OmpObjectList";
 }
+def OMPC_Indirect : Clause<"indirect"> {}
 def OMPC_Inbranch : Clause<"inbranch"> {}
 def OMPC_Notinbranch : Clause<"notinbranch"> {}
 def OMPC_Filter : Clause<"filter"> {
@@ -973,12 +974,14 @@ def OMP_BeginDeclareTarget : Directive<"begin declare target"> {
     VersionedClause<OMPC_To>,
     VersionedClause<OMPC_Link>,
     VersionedClause<OMPC_DeviceType>,
+    VersionedClause<OMPC_Indirect>
   ];
 }
 def OMP_DeclareTarget : Directive<"declare target"> {
   let allowedClauses = [
     VersionedClause<OMPC_To>,
-    VersionedClause<OMPC_Link>
+    VersionedClause<OMPC_Link>,
+    VersionedClause<OMPC_Indirect>
   ];
 }
 def OMP_EndDeclareTarget : Directive<"end declare target"> {}