[OpenMP] Parsing and sema support for thread_limit clause.

http://reviews.llvm.org/D15029

llvm-svn: 254207

clang/include/clang/AST/OpenMPClause.h

@@ -2783,6 +2783,61 @@ public:
   child_range children() { return child_range(&NumTeams, &NumTeams + 1); }
 };
 
+/// \brief This represents 'thread_limit' clause in the '#pragma omp ...'
+/// directive.
+///
+/// \code
+/// #pragma omp teams thread_limit(n)
+/// \endcode
+/// In this example directive '#pragma omp teams' has clause 'thread_limit'
+/// with single expression 'n'.
+///
+class OMPThreadLimitClause : public OMPClause {
+  friend class OMPClauseReader;
+  /// \brief Location of '('.
+  SourceLocation LParenLoc;
+  /// \brief ThreadLimit number.
+  Stmt *ThreadLimit;
+  /// \brief Set the ThreadLimit number.
+  ///
+  /// \param E ThreadLimit number.
+  ///
+  void setThreadLimit(Expr *E) { ThreadLimit = E; }
+
+public:
+  /// \brief Build 'thread_limit' clause.
+  ///
+  /// \param E Expression associated with this clause.
+  /// \param StartLoc Starting location of the clause.
+  /// \param LParenLoc Location of '('.
+  /// \param EndLoc Ending location of the clause.
+  ///
+  OMPThreadLimitClause(Expr *E, SourceLocation StartLoc,
+                       SourceLocation LParenLoc, SourceLocation EndLoc)
+      : OMPClause(OMPC_thread_limit, StartLoc, EndLoc), LParenLoc(LParenLoc),
+        ThreadLimit(E) {}
+
+  /// \brief Build an empty clause.
+  ///
+  OMPThreadLimitClause()
+      : OMPClause(OMPC_thread_limit, SourceLocation(), SourceLocation()),
+        LParenLoc(SourceLocation()), ThreadLimit(nullptr) {}
+  /// \brief Sets the location of '('.
+  void setLParenLoc(SourceLocation Loc) { LParenLoc = Loc; }
+  /// \brief Returns the location of '('.
+  SourceLocation getLParenLoc() const { return LParenLoc; }
+  /// \brief Return ThreadLimit number.
+  Expr *getThreadLimit() { return cast<Expr>(ThreadLimit); }
+  /// \brief Return ThreadLimit number.
+  Expr *getThreadLimit() const { return cast<Expr>(ThreadLimit); }
+
+  static bool classof(const OMPClause *T) {
+    return T->getClauseKind() == OMPC_thread_limit;
+  }
+
+  child_range children() { return child_range(&ThreadLimit, &ThreadLimit + 1); }
+};
+
 } // end namespace clang
 
 #endif // LLVM_CLANG_AST_OPENMPCLAUSE_H

clang/include/clang/AST/RecursiveASTVisitor.h

@@ -2728,6 +2728,13 @@ bool RecursiveASTVisitor<Derived>::VisitOMPNumTeamsClause(
   return true;
 }
 
+template <typename Derived>
+bool RecursiveASTVisitor<Derived>::VisitOMPThreadLimitClause(
+    OMPThreadLimitClause *C) {
+  TRY_TO(TraverseStmt(C->getThreadLimit()));
+  return true;
+}
+
 // FIXME: look at the following tricky-seeming exprs to see if we
 // need to recurse on anything.  These are ones that have methods
 // returning decls or qualtypes or nestednamespecifier -- though I'm

clang/include/clang/Basic/OpenMPKinds.def

@@ -151,6 +151,7 @@ OPENMP_CLAUSE(threads, OMPThreadsClause)
 OPENMP_CLAUSE(simd, OMPSIMDClause)
 OPENMP_CLAUSE(map, OMPMapClause)
 OPENMP_CLAUSE(num_teams, OMPNumTeamsClause)
+OPENMP_CLAUSE(thread_limit, OMPThreadLimitClause)
 
 // Clauses allowed for OpenMP directive 'parallel'.
 OPENMP_PARALLEL_CLAUSE(if)
@@ -323,6 +324,7 @@ OPENMP_TEAMS_CLAUSE(firstprivate)
 OPENMP_TEAMS_CLAUSE(shared)
 OPENMP_TEAMS_CLAUSE(reduction)
 OPENMP_TEAMS_CLAUSE(num_teams)
+OPENMP_TEAMS_CLAUSE(thread_limit)
 
 // Clauses allowed for OpenMP directive 'ordered'.
 // TODO More clauses for 'ordered' directive.

clang/include/clang/Sema/Sema.h

@@ -8125,6 +8125,11 @@ public:
   OMPClause *ActOnOpenMPNumTeamsClause(Expr *NumTeams, SourceLocation StartLoc,
                                        SourceLocation LParenLoc,
                                        SourceLocation EndLoc);
+  /// \brief Called on well-formed 'thread_limit' clause.
+  OMPClause *ActOnOpenMPThreadLimitClause(Expr *ThreadLimit,
+                                          SourceLocation StartLoc,
+                                          SourceLocation LParenLoc,
+                                          SourceLocation EndLoc);
 
   /// \brief The kind of conversion being performed.
   enum CheckedConversionKind {

clang/lib/AST/StmtPrinter.cpp

@@ -715,6 +715,12 @@ void OMPClausePrinter::VisitOMPNumTeamsClause(OMPNumTeamsClause *Node) {
   OS << ")";
 }
 
+void OMPClausePrinter::VisitOMPThreadLimitClause(OMPThreadLimitClause *Node) {
+  OS << "thread_limit(";
+  Node->getThreadLimit()->printPretty(OS, nullptr, Policy, 0);
+  OS << ")";
+}
+
 template<typename T>
 void OMPClausePrinter::VisitOMPClauseList(T *Node, char StartSym) {
   for (typename T::varlist_iterator I = Node->varlist_begin(),

clang/lib/AST/StmtProfile.cpp

@@ -456,6 +456,10 @@ void OMPClauseProfiler::VisitOMPMapClause(const OMPMapClause *C) {
 void OMPClauseProfiler::VisitOMPNumTeamsClause(const OMPNumTeamsClause *C) {
   Profiler->VisitStmt(C->getNumTeams());
 }
+void OMPClauseProfiler::VisitOMPThreadLimitClause(
+    const OMPThreadLimitClause *C) {
+  Profiler->VisitStmt(C->getThreadLimit());
+}
 }
 
 void

clang/lib/Basic/OpenMPKinds.cpp

@@ -136,6 +136,7 @@ unsigned clang::getOpenMPSimpleClauseType(OpenMPClauseKind Kind,
   case OMPC_threads:
   case OMPC_simd:
   case OMPC_num_teams:
+  case OMPC_thread_limit:
     break;
   }
   llvm_unreachable("Invalid OpenMP simple clause kind");
@@ -235,6 +236,7 @@ const char *clang::getOpenMPSimpleClauseTypeName(OpenMPClauseKind Kind,
   case OMPC_threads:
   case OMPC_simd:
   case OMPC_num_teams:
+  case OMPC_thread_limit:
     break;
   }
   llvm_unreachable("Invalid OpenMP simple clause kind");

clang/lib/CodeGen/CGStmtOpenMP.cpp

@@ -2435,6 +2435,7 @@ static void EmitOMPAtomicExpr(CodeGenFunction &CGF, OpenMPClauseKind Kind,
   case OMPC_simd:
   case OMPC_map:
   case OMPC_num_teams:
+  case OMPC_thread_limit:
     llvm_unreachable("Clause is not allowed in 'omp atomic'.");
   }
 }

clang/lib/Parse/ParseOpenMP.cpp

@@ -394,7 +394,8 @@ bool Parser::ParseOpenMPSimpleVarList(OpenMPDirectiveKind Kind,
 ///       schedule-clause | copyin-clause | copyprivate-clause | untied-clause |
 ///       mergeable-clause | flush-clause | read-clause | write-clause |
 ///       update-clause | capture-clause | seq_cst-clause | device-clause |
-///       simdlen-clause | threads-clause | simd-clause | num_teams-clause
+///       simdlen-clause | threads-clause | simd-clause | num_teams-clause |
+///       thread_limit-clause
 ///
 OMPClause *Parser::ParseOpenMPClause(OpenMPDirectiveKind DKind,
                                      OpenMPClauseKind CKind, bool FirstClause) {
@@ -416,6 +417,7 @@ OMPClause *Parser::ParseOpenMPClause(OpenMPDirectiveKind DKind,
   case OMPC_ordered:
   case OMPC_device:
   case OMPC_num_teams:
+  case OMPC_thread_limit:
     // OpenMP [2.5, Restrictions]
     //  At most one num_threads clause can appear on the directive.
     // OpenMP [2.8.1, simd construct, Restrictions]
@@ -429,6 +431,7 @@ OMPClause *Parser::ParseOpenMPClause(OpenMPDirectiveKind DKind,
     //  At most one final clause can appear on the directive.
     // OpenMP [teams Construct, Restrictions]
     //  At most one num_teams clause can appear on the directive.
+    //  At most one thread_limit clause can appear on the directive.
     if (!FirstClause) {
       Diag(Tok, diag::err_omp_more_one_clause)
           << getOpenMPDirectiveName(DKind) << getOpenMPClauseName(CKind) << 0;

clang/lib/Sema/SemaOpenMP.cpp

@@ -5097,6 +5097,9 @@ OMPClause *Sema::ActOnOpenMPSingleExprClause(OpenMPClauseKind Kind, Expr *Expr,
   case OMPC_num_teams:
     Res = ActOnOpenMPNumTeamsClause(Expr, StartLoc, LParenLoc, EndLoc);
     break;
+  case OMPC_thread_limit:
+    Res = ActOnOpenMPThreadLimitClause(Expr, StartLoc, LParenLoc, EndLoc);
+    break;
   case OMPC_if:
   case OMPC_default:
   case OMPC_proc_bind:
@@ -5214,31 +5217,39 @@ ExprResult Sema::PerformOpenMPImplicitIntegerConversion(SourceLocation Loc,
   return PerformContextualImplicitConversion(Loc, Op, ConvertDiagnoser);
 }
 
+static bool IsNonNegativeIntegerValue(Expr *&ValExpr, Sema &SemaRef,
+                                      OpenMPClauseKind CKind) {
+  if (!ValExpr->isTypeDependent() && !ValExpr->isValueDependent() &&
+      !ValExpr->isInstantiationDependent()) {
+    SourceLocation Loc = ValExpr->getExprLoc();
+    ExprResult Value =
+        SemaRef.PerformOpenMPImplicitIntegerConversion(Loc, ValExpr);
+    if (Value.isInvalid())
+      return false;
+
+    ValExpr = Value.get();
+    // The expression must evaluate to a non-negative integer value.
+    llvm::APSInt Result;
+    if (ValExpr->isIntegerConstantExpr(Result, SemaRef.Context) &&
+        Result.isSigned() && !Result.isStrictlyPositive()) {
+      SemaRef.Diag(Loc, diag::err_omp_negative_expression_in_clause)
+          << getOpenMPClauseName(CKind) << ValExpr->getSourceRange();
+      return false;
+    }
+  }
+  return true;
+}
+
 OMPClause *Sema::ActOnOpenMPNumThreadsClause(Expr *NumThreads,
                                              SourceLocation StartLoc,
                                              SourceLocation LParenLoc,
                                              SourceLocation EndLoc) {
   Expr *ValExpr = NumThreads;
-  if (!NumThreads->isValueDependent() && !NumThreads->isTypeDependent() &&
-      !NumThreads->containsUnexpandedParameterPack()) {
-    SourceLocation NumThreadsLoc = NumThreads->getLocStart();
-    ExprResult Val =
-        PerformOpenMPImplicitIntegerConversion(NumThreadsLoc, NumThreads);
-    if (Val.isInvalid())
-      return nullptr;
 
-    ValExpr = Val.get();
+  // OpenMP [2.5, Restrictions]
-
+  //  The num_threads expression must evaluate to a positive integer value.
-    // OpenMP [2.5, Restrictions]
+  if (!IsNonNegativeIntegerValue(ValExpr, *this, OMPC_num_threads))
-    //  The num_threads expression must evaluate to a positive integer value.
+    return nullptr;
-    llvm::APSInt Result;
-    if (ValExpr->isIntegerConstantExpr(Result, Context) && Result.isSigned() &&
-        !Result.isStrictlyPositive()) {
-      Diag(NumThreadsLoc, diag::err_omp_negative_expression_in_clause)
-          << "num_threads" << NumThreads->getSourceRange();
-      return nullptr;
-    }
-  }
 
   return new (Context)
       OMPNumThreadsClause(ValExpr, StartLoc, LParenLoc, EndLoc);
@@ -5385,6 +5396,7 @@ OMPClause *Sema::ActOnOpenMPSimpleClause(
   case OMPC_simd:
   case OMPC_map:
   case OMPC_num_teams:
+  case OMPC_thread_limit:
   case OMPC_unknown:
     llvm_unreachable("Clause is not allowed.");
   }
@@ -5516,6 +5528,7 @@ OMPClause *Sema::ActOnOpenMPSingleExprWithArgClause(
   case OMPC_simd:
   case OMPC_map:
   case OMPC_num_teams:
+  case OMPC_thread_limit:
   case OMPC_unknown:
     llvm_unreachable("Clause is not allowed.");
   }
@@ -5649,6 +5662,7 @@ OMPClause *Sema::ActOnOpenMPClause(OpenMPClauseKind Kind,
   case OMPC_device:
   case OMPC_map:
   case OMPC_num_teams:
+  case OMPC_thread_limit:
   case OMPC_unknown:
     llvm_unreachable("Clause is not allowed.");
   }
@@ -5779,6 +5793,7 @@ OMPClause *Sema::ActOnOpenMPVarListClause(
   case OMPC_threads:
   case OMPC_simd:
   case OMPC_num_teams:
+  case OMPC_thread_limit:
   case OMPC_unknown:
     llvm_unreachable("Clause is not allowed.");
   }
@@ -7458,23 +7473,12 @@ OMPClause *Sema::ActOnOpenMPDeviceClause(Expr *Device, SourceLocation StartLoc,
                                          SourceLocation LParenLoc,
                                          SourceLocation EndLoc) {
   Expr *ValExpr = Device;
-  if (!ValExpr->isTypeDependent() && !ValExpr->isValueDependent() &&
-      !ValExpr->isInstantiationDependent()) {
-    SourceLocation Loc = ValExpr->getExprLoc();
-    ExprResult Value = PerformOpenMPImplicitIntegerConversion(Loc, ValExpr);
-    if (Value.isInvalid())
-      return nullptr;
 
-    // OpenMP [2.9.1, Restrictions]
+  // OpenMP [2.9.1, Restrictions]
-    // The device expression must evaluate to a non-negative integer value.
+  // The device expression must evaluate to a non-negative integer value.
-    llvm::APSInt Result;
+  if (!IsNonNegativeIntegerValue(ValExpr, *this, OMPC_device))
-    if (Value.get()->isIntegerConstantExpr(Result, Context) && 
+    return nullptr;
-        Result.isSigned() && !Result.isStrictlyPositive()) {
+
-      Diag(Loc, diag::err_omp_negative_expression_in_clause)
-          << "device" << ValExpr->getSourceRange();
-      return nullptr;
-    }
-  }
   return new (Context) OMPDeviceClause(ValExpr, StartLoc, LParenLoc, EndLoc);
 }
 
@@ -7659,23 +7663,26 @@ OMPClause *Sema::ActOnOpenMPNumTeamsClause(Expr *NumTeams,
                                            SourceLocation LParenLoc,
                                            SourceLocation EndLoc) {
   Expr *ValExpr = NumTeams;
-  if (!ValExpr->isTypeDependent() && !ValExpr->isValueDependent() &&
-      !ValExpr->isInstantiationDependent()) {
-    SourceLocation Loc = ValExpr->getExprLoc();
-    ExprResult Value = PerformOpenMPImplicitIntegerConversion(Loc, ValExpr);
-    if (Value.isInvalid())
-      return nullptr;
 
-    // OpenMP [teams Constrcut, Restrictions]
+  // OpenMP [teams Constrcut, Restrictions]
-    // The num_teams expression must evaluate to a positive integer value.
+  // The num_teams expression must evaluate to a positive integer value.
-    llvm::APSInt Result;
+  if (!IsNonNegativeIntegerValue(ValExpr, *this, OMPC_num_teams))
-    if (Value.get()->isIntegerConstantExpr(Result, Context) && 
+    return nullptr;
-        Result.isSigned() && !Result.isStrictlyPositive()) {
-      Diag(Loc, diag::err_omp_negative_expression_in_clause)
-          << "num_teams" << ValExpr->getSourceRange();
-      return nullptr;
-    }
-  }
 
   return new (Context) OMPNumTeamsClause(ValExpr, StartLoc, LParenLoc, EndLoc);
 }
+
+OMPClause *Sema::ActOnOpenMPThreadLimitClause(Expr *ThreadLimit,
+                                              SourceLocation StartLoc,
+                                              SourceLocation LParenLoc,
+                                              SourceLocation EndLoc) {
+  Expr *ValExpr = ThreadLimit;
+
+  // OpenMP [teams Constrcut, Restrictions]
+  // The thread_limit expression must evaluate to a positive integer value.
+  if (!IsNonNegativeIntegerValue(ValExpr, *this, OMPC_thread_limit))
+    return nullptr;
+
+  return new (Context) OMPThreadLimitClause(ValExpr, StartLoc, LParenLoc,
+                                            EndLoc);
+}

clang/lib/Sema/TreeTransform.h

@@ -1677,6 +1677,18 @@ public:
                                                EndLoc);
   }
 
+  /// \brief Build a new OpenMP 'thread_limit' clause.
+  ///
+  /// By default, performs semantic analysis to build the new statement.
+  /// Subclasses may override this routine to provide different behavior.
+  OMPClause *RebuildOMPThreadLimitClause(Expr *ThreadLimit,
+                                         SourceLocation StartLoc,
+                                         SourceLocation LParenLoc,
+                                         SourceLocation EndLoc) {
+    return getSema().ActOnOpenMPThreadLimitClause(ThreadLimit, StartLoc,
+                                                  LParenLoc, EndLoc);
+  }
+
   /// \brief Rebuild the operand to an Objective-C \@synchronized statement.
   ///
   /// By default, performs semantic analysis to build the new statement.
@@ -7718,6 +7730,16 @@ TreeTransform<Derived>::TransformOMPNumTeamsClause(OMPNumTeamsClause *C) {
       E.get(), C->getLocStart(), C->getLParenLoc(), C->getLocEnd());
 }
 
+template <typename Derived>
+OMPClause *
+TreeTransform<Derived>::TransformOMPThreadLimitClause(OMPThreadLimitClause *C) {
+  ExprResult E = getDerived().TransformExpr(C->getThreadLimit());
+  if (E.isInvalid())
+    return nullptr;
+  return getDerived().RebuildOMPThreadLimitClause(
+      E.get(), C->getLocStart(), C->getLParenLoc(), C->getLocEnd());
+}
+
 //===----------------------------------------------------------------------===//
 // Expression transformation
 //===----------------------------------------------------------------------===//

clang/lib/Serialization/ASTReaderStmt.cpp

@@ -1853,6 +1853,9 @@ OMPClause *OMPClauseReader::readClause() {
   case OMPC_num_teams:
     C = new (Context) OMPNumTeamsClause();
     break;
+  case OMPC_thread_limit:
+    C = new (Context) OMPThreadLimitClause();
+    break;
   }
   Visit(C);
   C->setLocStart(Reader->ReadSourceLocation(Record, Idx));
@@ -2182,6 +2185,11 @@ void OMPClauseReader::VisitOMPNumTeamsClause(OMPNumTeamsClause *C) {
   C->setLParenLoc(Reader->ReadSourceLocation(Record, Idx));
 }
 
+void OMPClauseReader::VisitOMPThreadLimitClause(OMPThreadLimitClause *C) {
+  C->setThreadLimit(Reader->Reader.ReadSubExpr());
+  C->setLParenLoc(Reader->ReadSourceLocation(Record, Idx));
+}
+
 //===----------------------------------------------------------------------===//
 // OpenMP Directives.
 //===----------------------------------------------------------------------===//

clang/lib/Serialization/ASTWriterStmt.cpp

@@ -2006,6 +2006,11 @@ void OMPClauseWriter::VisitOMPNumTeamsClause(OMPNumTeamsClause *C) {
   Writer->Writer.AddSourceLocation(C->getLParenLoc(), Record);
 }
 
+void OMPClauseWriter::VisitOMPThreadLimitClause(OMPThreadLimitClause *C) {
+  Writer->Writer.AddStmt(C->getThreadLimit());
+  Writer->Writer.AddSourceLocation(C->getLParenLoc(), Record);
+}
+
 //===----------------------------------------------------------------------===//
 // OpenMP Directives.
 //===----------------------------------------------------------------------===//

clang/test/OpenMP/teams_ast_print.cpp

@@ -37,7 +37,7 @@ T tmain(T argc, T *argv) {
 #pragma omp teams
   a=2;
 #pragma omp target
-#pragma omp teams default(none), private(argc,b) firstprivate(argv) shared (d) reduction(+:c) reduction(max:e) num_teams(C)
+#pragma omp teams default(none), private(argc,b) firstprivate(argv) shared (d) reduction(+:c) reduction(max:e) num_teams(C) thread_limit(d*C)
   foo();
 #pragma omp target
 #pragma omp teams reduction(^:e, f) reduction(&& : g)
@@ -53,7 +53,7 @@ T tmain(T argc, T *argv) {
 // CHECK-NEXT: #pragma omp teams
 // CHECK-NEXT: a = 2;
 // CHECK-NEXT: #pragma omp target
-// CHECK-NEXT: #pragma omp teams default(none) private(argc,b) firstprivate(argv) shared(d) reduction(+: c) reduction(max: e) num_teams(5)
+// CHECK-NEXT: #pragma omp teams default(none) private(argc,b) firstprivate(argv) shared(d) reduction(+: c) reduction(max: e) num_teams(5) thread_limit(d * 5)
 // CHECK-NEXT: foo()
 // CHECK-NEXT: #pragma omp target
 // CHECK-NEXT: #pragma omp teams reduction(^: e,f) reduction(&&: g)
@@ -66,7 +66,7 @@ T tmain(T argc, T *argv) {
 // CHECK-NEXT: #pragma omp teams
 // CHECK-NEXT: a = 2;
 // CHECK-NEXT: #pragma omp target
-// CHECK-NEXT: #pragma omp teams default(none) private(argc,b) firstprivate(argv) shared(d) reduction(+: c) reduction(max: e) num_teams(1)
+// CHECK-NEXT: #pragma omp teams default(none) private(argc,b) firstprivate(argv) shared(d) reduction(+: c) reduction(max: e) num_teams(1) thread_limit(d * 1)
 // CHECK-NEXT: foo()
 // CHECK-NEXT: #pragma omp target
 // CHECK-NEXT: #pragma omp teams reduction(^: e,f) reduction(&&: g)
@@ -79,7 +79,7 @@ T tmain(T argc, T *argv) {
 // CHECK-NEXT: #pragma omp teams
 // CHECK-NEXT: a = 2;
 // CHECK-NEXT: #pragma omp target
-// CHECK-NEXT: #pragma omp teams default(none) private(argc,b) firstprivate(argv) shared(d) reduction(+: c) reduction(max: e) num_teams(C)
+// CHECK-NEXT: #pragma omp teams default(none) private(argc,b) firstprivate(argv) shared(d) reduction(+: c) reduction(max: e) num_teams(C) thread_limit(d * C)
 // CHECK-NEXT: foo()
 // CHECK-NEXT: #pragma omp target
 // CHECK-NEXT: #pragma omp teams reduction(^: e,f) reduction(&&: g)
@@ -101,9 +101,9 @@ int main (int argc, char **argv) {
   a=2;
 // CHECK-NEXT: a = 2;
 #pragma omp target
-#pragma omp teams default(none), private(argc,b) num_teams(f) firstprivate(argv) reduction(| : c, d) reduction(* : e)
+#pragma omp teams default(none), private(argc,b) num_teams(f) firstprivate(argv) reduction(| : c, d) reduction(* : e) thread_limit(f+g)
 // CHECK-NEXT: #pragma omp target
-// CHECK-NEXT: #pragma omp teams default(none) private(argc,b) num_teams(f) firstprivate(argv) reduction(|: c,d) reduction(*: e)
+// CHECK-NEXT: #pragma omp teams default(none) private(argc,b) num_teams(f) firstprivate(argv) reduction(|: c,d) reduction(*: e) thread_limit(f + g)
   foo();
 // CHECK-NEXT: foo();
   return tmain<int, 5>(b, &b) + tmain<long, 1>(x, &x);

clang/test/OpenMP/teams_thread_limit_messages.cpp

@@ -0,0 +1,111 @@
+// RUN: %clang_cc1 -verify -fopenmp -std=c++11 -ferror-limit 100 -o - %s
+
+void foo() {
+}
+
+bool foobool(int argc) {
+  return argc;
+}
+
+struct S1; // expected-note 2 {{declared here}}
+
+template <typename T, int C> // expected-note {{declared here}}
+T tmain(T argc) {
+  char **a;
+#pragma omp target
+#pragma omp teams thread_limit(C)
+  foo();
+#pragma omp target
+#pragma omp teams thread_limit(T) // expected-error {{'T' does not refer to a value}}
+  foo();
+#pragma omp target
+#pragma omp teams thread_limit // expected-error {{expected '(' after 'thread_limit'}}
+  foo();
+#pragma omp target
+#pragma omp teams thread_limit( // expected-error {{expected expression}} expected-error {{expected ')'}} expected-note {{to match this '('}}
+  foo();
+#pragma omp target
+#pragma omp teams thread_limit() // expected-error {{expected expression}}
+  foo();
+#pragma omp target
+#pragma omp teams thread_limit(argc // expected-error {{expected ')'}} expected-note {{to match this '('}}
+  foo();
+#pragma omp target
+#pragma omp teams thread_limit(argc)) // expected-warning {{extra tokens at the end of '#pragma omp teams' are ignored}}
+  foo();
+#pragma omp target
+#pragma omp teams thread_limit(argc > 0 ? a[1] : a[2]) // expected-error {{expression must have integral or unscoped enumeration type, not 'char *'}}
+  foo();
+#pragma omp target
+#pragma omp teams thread_limit(argc + argc)
+  foo();
+#pragma omp target
+#pragma omp teams thread_limit(argc), thread_limit (argc+1) // expected-error {{directive '#pragma omp teams' cannot contain more than one 'thread_limit' clause}}
+  foo();
+#pragma omp target
+#pragma omp teams thread_limit(S1) // expected-error {{'S1' does not refer to a value}}
+  foo();
+#pragma omp target
+#pragma omp teams thread_limit(-2) // expected-error {{argument to 'thread_limit' clause must be a positive integer value}}
+  foo();
+#pragma omp target
+#pragma omp teams thread_limit(-10u)
+  foo();
+#pragma omp target
+#pragma omp teams thread_limit(3.14) // expected-error 2 {{expression must have integral or unscoped enumeration type, not 'double'}}
+  foo();
+
+  return 0;
+}
+
+int main(int argc, char **argv) {
+#pragma omp target
+#pragma omp teams thread_limit // expected-error {{expected '(' after 'thread_limit'}}
+  foo();
+
+#pragma omp target
+#pragma omp teams thread_limit ( // expected-error {{expected expression}} expected-error {{expected ')'}} expected-note {{to match this '('}}
+  foo();
+
+#pragma omp target
+#pragma omp teams thread_limit () // expected-error {{expected expression}}
+  foo();
+
+#pragma omp target
+#pragma omp teams thread_limit (argc // expected-error {{expected ')'}} expected-note {{to match this '('}}
+  foo();
+
+#pragma omp target
+#pragma omp teams thread_limit (argc)) // expected-warning {{extra tokens at the end of '#pragma omp teams' are ignored}}
+  foo();
+
+#pragma omp target
+#pragma omp teams thread_limit (argc > 0 ? argv[1] : argv[2]) // expected-error {{expression must have integral or unscoped enumeration type, not 'char *'}}
+  foo();
+
+#pragma omp target
+#pragma omp teams thread_limit (argc + argc)
+  foo();
+
+#pragma omp target
+#pragma omp teams thread_limit (argc), thread_limit (argc+1) // expected-error {{directive '#pragma omp teams' cannot contain more than one 'thread_limit' clause}}
+  foo();
+
+#pragma omp target
+#pragma omp teams thread_limit (S1) // expected-error {{'S1' does not refer to a value}}
+  foo();
+
+#pragma omp target
+#pragma omp teams thread_limit (-2) // expected-error {{argument to 'thread_limit' clause must be a positive integer value}}
+  foo();
+
+#pragma omp target
+#pragma omp teams thread_limit (-10u)
+  foo();
+
+#pragma omp target
+#pragma omp teams thread_limit (3.14) // expected-error {{expression must have integral or unscoped enumeration type, not 'double'}}
+  foo();
+
+  return tmain<int, 10>(argc); // expected-note {{in instantiation of function template specialization 'tmain<int, 10>' requested here}}
+}

clang/tools/libclang/CIndex.cpp

@@ -2079,6 +2079,10 @@ void OMPClauseEnqueue::VisitOMPNumTeamsClause(const OMPNumTeamsClause *C) {
   Visitor->AddStmt(C->getNumTeams());
 }
 
+void OMPClauseEnqueue::VisitOMPThreadLimitClause(const OMPThreadLimitClause *C) {
+  Visitor->AddStmt(C->getThreadLimit());
+}
+
 template<typename T>
 void OMPClauseEnqueue::VisitOMPClauseList(T *Node) {
   for (const auto *I : Node->varlists()) {