1 //===--- ParseOpenMP.cpp - OpenMP directives parsing ----------------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 /// \file
10 /// This file implements parsing of all OpenMP directives and clauses.
11 ///
12 //===----------------------------------------------------------------------===//
13 
14 #include "clang/AST/ASTContext.h"
15 #include "clang/AST/StmtOpenMP.h"
16 #include "clang/Parse/ParseDiagnostic.h"
17 #include "clang/Parse/Parser.h"
18 #include "clang/Parse/RAIIObjectsForParser.h"
19 #include "clang/Sema/Scope.h"
20 #include "llvm/ADT/PointerIntPair.h"
21 
22 using namespace clang;
23 
24 //===----------------------------------------------------------------------===//
25 // OpenMP declarative directives.
26 //===----------------------------------------------------------------------===//
27 
28 namespace {
29 enum OpenMPDirectiveKindEx {
30   OMPD_cancellation = OMPD_unknown + 1,
31   OMPD_data,
32   OMPD_declare,
33   OMPD_end,
34   OMPD_end_declare,
35   OMPD_enter,
36   OMPD_exit,
37   OMPD_point,
38   OMPD_reduction,
39   OMPD_target_enter,
40   OMPD_target_exit,
41   OMPD_update,
42   OMPD_distribute_parallel,
43   OMPD_teams_distribute_parallel,
44   OMPD_target_teams_distribute_parallel
45 };
46 
47 class ThreadprivateListParserHelper final {
48   SmallVector<Expr *, 4> Identifiers;
49   Parser *P;
50 
51 public:
52   ThreadprivateListParserHelper(Parser *P) : P(P) {}
53   void operator()(CXXScopeSpec &SS, DeclarationNameInfo NameInfo) {
54     ExprResult Res =
55         P->getActions().ActOnOpenMPIdExpression(P->getCurScope(), SS, NameInfo);
56     if (Res.isUsable())
57       Identifiers.push_back(Res.get());
58   }
59   llvm::ArrayRef<Expr *> getIdentifiers() const { return Identifiers; }
60 };
61 } // namespace
62 
63 // Map token string to extended OMP token kind that are
64 // OpenMPDirectiveKind + OpenMPDirectiveKindEx.
65 static unsigned getOpenMPDirectiveKindEx(StringRef S) {
66   auto DKind = getOpenMPDirectiveKind(S);
67   if (DKind != OMPD_unknown)
68     return DKind;
69 
70   return llvm::StringSwitch<unsigned>(S)
71       .Case("cancellation", OMPD_cancellation)
72       .Case("data", OMPD_data)
73       .Case("declare", OMPD_declare)
74       .Case("end", OMPD_end)
75       .Case("enter", OMPD_enter)
76       .Case("exit", OMPD_exit)
77       .Case("point", OMPD_point)
78       .Case("reduction", OMPD_reduction)
79       .Case("update", OMPD_update)
80       .Default(OMPD_unknown);
81 }
82 
83 static OpenMPDirectiveKind parseOpenMPDirectiveKind(Parser &P) {
84   // Array of foldings: F[i][0] F[i][1] ===> F[i][2].
85   // E.g.: OMPD_for OMPD_simd ===> OMPD_for_simd
86   // TODO: add other combined directives in topological order.
87   static const unsigned F[][3] = {
88       {OMPD_cancellation, OMPD_point, OMPD_cancellation_point},
89       {OMPD_declare, OMPD_reduction, OMPD_declare_reduction},
90       {OMPD_declare, OMPD_simd, OMPD_declare_simd},
91       {OMPD_declare, OMPD_target, OMPD_declare_target},
92       {OMPD_distribute, OMPD_parallel, OMPD_distribute_parallel},
93       {OMPD_distribute_parallel, OMPD_for, OMPD_distribute_parallel_for},
94       {OMPD_distribute_parallel_for, OMPD_simd,
95        OMPD_distribute_parallel_for_simd},
96       {OMPD_distribute, OMPD_simd, OMPD_distribute_simd},
97       {OMPD_end, OMPD_declare, OMPD_end_declare},
98       {OMPD_end_declare, OMPD_target, OMPD_end_declare_target},
99       {OMPD_target, OMPD_data, OMPD_target_data},
100       {OMPD_target, OMPD_enter, OMPD_target_enter},
101       {OMPD_target, OMPD_exit, OMPD_target_exit},
102       {OMPD_target, OMPD_update, OMPD_target_update},
103       {OMPD_target_enter, OMPD_data, OMPD_target_enter_data},
104       {OMPD_target_exit, OMPD_data, OMPD_target_exit_data},
105       {OMPD_for, OMPD_simd, OMPD_for_simd},
106       {OMPD_parallel, OMPD_for, OMPD_parallel_for},
107       {OMPD_parallel_for, OMPD_simd, OMPD_parallel_for_simd},
108       {OMPD_parallel, OMPD_sections, OMPD_parallel_sections},
109       {OMPD_taskloop, OMPD_simd, OMPD_taskloop_simd},
110       {OMPD_target, OMPD_parallel, OMPD_target_parallel},
111       {OMPD_target, OMPD_simd, OMPD_target_simd},
112       {OMPD_target_parallel, OMPD_for, OMPD_target_parallel_for},
113       {OMPD_target_parallel_for, OMPD_simd, OMPD_target_parallel_for_simd},
114       {OMPD_teams, OMPD_distribute, OMPD_teams_distribute},
115       {OMPD_teams_distribute, OMPD_simd, OMPD_teams_distribute_simd},
116       {OMPD_teams_distribute, OMPD_parallel, OMPD_teams_distribute_parallel},
117       {OMPD_teams_distribute_parallel, OMPD_for,
118        OMPD_teams_distribute_parallel_for},
119       {OMPD_teams_distribute_parallel_for, OMPD_simd,
120        OMPD_teams_distribute_parallel_for_simd},
121       {OMPD_target, OMPD_teams, OMPD_target_teams},
122       {OMPD_target_teams, OMPD_distribute, OMPD_target_teams_distribute},
123       {OMPD_target_teams_distribute, OMPD_parallel,
124        OMPD_target_teams_distribute_parallel},
125       {OMPD_target_teams_distribute, OMPD_simd,
126        OMPD_target_teams_distribute_simd},
127       {OMPD_target_teams_distribute_parallel, OMPD_for,
128        OMPD_target_teams_distribute_parallel_for},
129       {OMPD_target_teams_distribute_parallel_for, OMPD_simd,
130        OMPD_target_teams_distribute_parallel_for_simd}};
131   enum { CancellationPoint = 0, DeclareReduction = 1, TargetData = 2 };
132   Token Tok = P.getCurToken();
133   unsigned DKind =
134       Tok.isAnnotation()
135           ? static_cast<unsigned>(OMPD_unknown)
136           : getOpenMPDirectiveKindEx(P.getPreprocessor().getSpelling(Tok));
137   if (DKind == OMPD_unknown)
138     return OMPD_unknown;
139 
140   for (unsigned I = 0; I < llvm::array_lengthof(F); ++I) {
141     if (DKind != F[I][0])
142       continue;
143 
144     Tok = P.getPreprocessor().LookAhead(0);
145     unsigned SDKind =
146         Tok.isAnnotation()
147             ? static_cast<unsigned>(OMPD_unknown)
148             : getOpenMPDirectiveKindEx(P.getPreprocessor().getSpelling(Tok));
149     if (SDKind == OMPD_unknown)
150       continue;
151 
152     if (SDKind == F[I][1]) {
153       P.ConsumeToken();
154       DKind = F[I][2];
155     }
156   }
157   return DKind < OMPD_unknown ? static_cast<OpenMPDirectiveKind>(DKind)
158                               : OMPD_unknown;
159 }
160 
161 static DeclarationName parseOpenMPReductionId(Parser &P) {
162   Token Tok = P.getCurToken();
163   Sema &Actions = P.getActions();
164   OverloadedOperatorKind OOK = OO_None;
165   // Allow to use 'operator' keyword for C++ operators
166   bool WithOperator = false;
167   if (Tok.is(tok::kw_operator)) {
168     P.ConsumeToken();
169     Tok = P.getCurToken();
170     WithOperator = true;
171   }
172   switch (Tok.getKind()) {
173   case tok::plus: // '+'
174     OOK = OO_Plus;
175     break;
176   case tok::minus: // '-'
177     OOK = OO_Minus;
178     break;
179   case tok::star: // '*'
180     OOK = OO_Star;
181     break;
182   case tok::amp: // '&'
183     OOK = OO_Amp;
184     break;
185   case tok::pipe: // '|'
186     OOK = OO_Pipe;
187     break;
188   case tok::caret: // '^'
189     OOK = OO_Caret;
190     break;
191   case tok::ampamp: // '&&'
192     OOK = OO_AmpAmp;
193     break;
194   case tok::pipepipe: // '||'
195     OOK = OO_PipePipe;
196     break;
197   case tok::identifier: // identifier
198     if (!WithOperator)
199       break;
200     LLVM_FALLTHROUGH;
201   default:
202     P.Diag(Tok.getLocation(), diag::err_omp_expected_reduction_identifier);
203     P.SkipUntil(tok::colon, tok::r_paren, tok::annot_pragma_openmp_end,
204                 Parser::StopBeforeMatch);
205     return DeclarationName();
206   }
207   P.ConsumeToken();
208   auto &DeclNames = Actions.getASTContext().DeclarationNames;
209   return OOK == OO_None ? DeclNames.getIdentifier(Tok.getIdentifierInfo())
210                         : DeclNames.getCXXOperatorName(OOK);
211 }
212 
213 /// Parse 'omp declare reduction' construct.
214 ///
215 ///       declare-reduction-directive:
216 ///        annot_pragma_openmp 'declare' 'reduction'
217 ///        '(' <reduction_id> ':' <type> {',' <type>} ':' <expression> ')'
218 ///        ['initializer' '(' ('omp_priv' '=' <expression>)|<function_call> ')']
219 ///        annot_pragma_openmp_end
220 /// <reduction_id> is either a base language identifier or one of the following
221 /// operators: '+', '-', '*', '&', '|', '^', '&&' and '||'.
222 ///
223 Parser::DeclGroupPtrTy
224 Parser::ParseOpenMPDeclareReductionDirective(AccessSpecifier AS) {
225   // Parse '('.
226   BalancedDelimiterTracker T(*this, tok::l_paren, tok::annot_pragma_openmp_end);
227   if (T.expectAndConsume(diag::err_expected_lparen_after,
228                          getOpenMPDirectiveName(OMPD_declare_reduction))) {
229     SkipUntil(tok::annot_pragma_openmp_end, StopBeforeMatch);
230     return DeclGroupPtrTy();
231   }
232 
233   DeclarationName Name = parseOpenMPReductionId(*this);
234   if (Name.isEmpty() && Tok.is(tok::annot_pragma_openmp_end))
235     return DeclGroupPtrTy();
236 
237   // Consume ':'.
238   bool IsCorrect = !ExpectAndConsume(tok::colon);
239 
240   if (!IsCorrect && Tok.is(tok::annot_pragma_openmp_end))
241     return DeclGroupPtrTy();
242 
243   IsCorrect = IsCorrect && !Name.isEmpty();
244 
245   if (Tok.is(tok::colon) || Tok.is(tok::annot_pragma_openmp_end)) {
246     Diag(Tok.getLocation(), diag::err_expected_type);
247     IsCorrect = false;
248   }
249 
250   if (!IsCorrect && Tok.is(tok::annot_pragma_openmp_end))
251     return DeclGroupPtrTy();
252 
253   SmallVector<std::pair<QualType, SourceLocation>, 8> ReductionTypes;
254   // Parse list of types until ':' token.
255   do {
256     ColonProtectionRAIIObject ColonRAII(*this);
257     SourceRange Range;
258     TypeResult TR =
259         ParseTypeName(&Range, DeclaratorContext::PrototypeContext, AS);
260     if (TR.isUsable()) {
261       QualType ReductionType =
262           Actions.ActOnOpenMPDeclareReductionType(Range.getBegin(), TR);
263       if (!ReductionType.isNull()) {
264         ReductionTypes.push_back(
265             std::make_pair(ReductionType, Range.getBegin()));
266       }
267     } else {
268       SkipUntil(tok::comma, tok::colon, tok::annot_pragma_openmp_end,
269                 StopBeforeMatch);
270     }
271 
272     if (Tok.is(tok::colon) || Tok.is(tok::annot_pragma_openmp_end))
273       break;
274 
275     // Consume ','.
276     if (ExpectAndConsume(tok::comma)) {
277       IsCorrect = false;
278       if (Tok.is(tok::annot_pragma_openmp_end)) {
279         Diag(Tok.getLocation(), diag::err_expected_type);
280         return DeclGroupPtrTy();
281       }
282     }
283   } while (Tok.isNot(tok::annot_pragma_openmp_end));
284 
285   if (ReductionTypes.empty()) {
286     SkipUntil(tok::annot_pragma_openmp_end, StopBeforeMatch);
287     return DeclGroupPtrTy();
288   }
289 
290   if (!IsCorrect && Tok.is(tok::annot_pragma_openmp_end))
291     return DeclGroupPtrTy();
292 
293   // Consume ':'.
294   if (ExpectAndConsume(tok::colon))
295     IsCorrect = false;
296 
297   if (Tok.is(tok::annot_pragma_openmp_end)) {
298     Diag(Tok.getLocation(), diag::err_expected_expression);
299     return DeclGroupPtrTy();
300   }
301 
302   DeclGroupPtrTy DRD = Actions.ActOnOpenMPDeclareReductionDirectiveStart(
303       getCurScope(), Actions.getCurLexicalContext(), Name, ReductionTypes, AS);
304 
305   // Parse <combiner> expression and then parse initializer if any for each
306   // correct type.
307   unsigned I = 0, E = ReductionTypes.size();
308   for (Decl *D : DRD.get()) {
309     TentativeParsingAction TPA(*this);
310     ParseScope OMPDRScope(this, Scope::FnScope | Scope::DeclScope |
311                                     Scope::CompoundStmtScope |
312                                     Scope::OpenMPDirectiveScope);
313     // Parse <combiner> expression.
314     Actions.ActOnOpenMPDeclareReductionCombinerStart(getCurScope(), D);
315     ExprResult CombinerResult =
316         Actions.ActOnFinishFullExpr(ParseAssignmentExpression().get(),
317                                     D->getLocation(), /*DiscardedValue=*/true);
318     Actions.ActOnOpenMPDeclareReductionCombinerEnd(D, CombinerResult.get());
319 
320     if (CombinerResult.isInvalid() && Tok.isNot(tok::r_paren) &&
321         Tok.isNot(tok::annot_pragma_openmp_end)) {
322       TPA.Commit();
323       IsCorrect = false;
324       break;
325     }
326     IsCorrect = !T.consumeClose() && IsCorrect && CombinerResult.isUsable();
327     ExprResult InitializerResult;
328     if (Tok.isNot(tok::annot_pragma_openmp_end)) {
329       // Parse <initializer> expression.
330       if (Tok.is(tok::identifier) &&
331           Tok.getIdentifierInfo()->isStr("initializer")) {
332         ConsumeToken();
333       } else {
334         Diag(Tok.getLocation(), diag::err_expected) << "'initializer'";
335         TPA.Commit();
336         IsCorrect = false;
337         break;
338       }
339       // Parse '('.
340       BalancedDelimiterTracker T(*this, tok::l_paren,
341                                  tok::annot_pragma_openmp_end);
342       IsCorrect =
343           !T.expectAndConsume(diag::err_expected_lparen_after, "initializer") &&
344           IsCorrect;
345       if (Tok.isNot(tok::annot_pragma_openmp_end)) {
346         ParseScope OMPDRScope(this, Scope::FnScope | Scope::DeclScope |
347                                         Scope::CompoundStmtScope |
348                                         Scope::OpenMPDirectiveScope);
349         // Parse expression.
350         VarDecl *OmpPrivParm =
351             Actions.ActOnOpenMPDeclareReductionInitializerStart(getCurScope(),
352                                                                 D);
353         // Check if initializer is omp_priv <init_expr> or something else.
354         if (Tok.is(tok::identifier) &&
355             Tok.getIdentifierInfo()->isStr("omp_priv")) {
356           if (Actions.getLangOpts().CPlusPlus) {
357             InitializerResult = Actions.ActOnFinishFullExpr(
358                 ParseAssignmentExpression().get(), D->getLocation(),
359                 /*DiscardedValue=*/true);
360           } else {
361             ConsumeToken();
362             ParseOpenMPReductionInitializerForDecl(OmpPrivParm);
363           }
364         } else {
365           InitializerResult = Actions.ActOnFinishFullExpr(
366               ParseAssignmentExpression().get(), D->getLocation(),
367               /*DiscardedValue=*/true);
368         }
369         Actions.ActOnOpenMPDeclareReductionInitializerEnd(
370             D, InitializerResult.get(), OmpPrivParm);
371         if (InitializerResult.isInvalid() && Tok.isNot(tok::r_paren) &&
372             Tok.isNot(tok::annot_pragma_openmp_end)) {
373           TPA.Commit();
374           IsCorrect = false;
375           break;
376         }
377         IsCorrect =
378             !T.consumeClose() && IsCorrect && !InitializerResult.isInvalid();
379       }
380     }
381 
382     ++I;
383     // Revert parsing if not the last type, otherwise accept it, we're done with
384     // parsing.
385     if (I != E)
386       TPA.Revert();
387     else
388       TPA.Commit();
389   }
390   return Actions.ActOnOpenMPDeclareReductionDirectiveEnd(getCurScope(), DRD,
391                                                          IsCorrect);
392 }
393 
394 void Parser::ParseOpenMPReductionInitializerForDecl(VarDecl *OmpPrivParm) {
395   // Parse declarator '=' initializer.
396   // If a '==' or '+=' is found, suggest a fixit to '='.
397   if (isTokenEqualOrEqualTypo()) {
398     ConsumeToken();
399 
400     if (Tok.is(tok::code_completion)) {
401       Actions.CodeCompleteInitializer(getCurScope(), OmpPrivParm);
402       Actions.FinalizeDeclaration(OmpPrivParm);
403       cutOffParsing();
404       return;
405     }
406 
407     ExprResult Init(ParseInitializer());
408 
409     if (Init.isInvalid()) {
410       SkipUntil(tok::r_paren, tok::annot_pragma_openmp_end, StopBeforeMatch);
411       Actions.ActOnInitializerError(OmpPrivParm);
412     } else {
413       Actions.AddInitializerToDecl(OmpPrivParm, Init.get(),
414                                    /*DirectInit=*/false);
415     }
416   } else if (Tok.is(tok::l_paren)) {
417     // Parse C++ direct initializer: '(' expression-list ')'
418     BalancedDelimiterTracker T(*this, tok::l_paren);
419     T.consumeOpen();
420 
421     ExprVector Exprs;
422     CommaLocsTy CommaLocs;
423 
424     SourceLocation LParLoc = T.getOpenLocation();
425     if (ParseExpressionList(
426             Exprs, CommaLocs, [this, OmpPrivParm, LParLoc, &Exprs] {
427               QualType PreferredType = Actions.ProduceConstructorSignatureHelp(
428                   getCurScope(),
429                   OmpPrivParm->getType()->getCanonicalTypeInternal(),
430                   OmpPrivParm->getLocation(), Exprs, LParLoc);
431               CalledSignatureHelp = true;
432               Actions.CodeCompleteExpression(getCurScope(), PreferredType);
433             })) {
434       if (PP.isCodeCompletionReached() && !CalledSignatureHelp) {
435         Actions.ProduceConstructorSignatureHelp(
436             getCurScope(), OmpPrivParm->getType()->getCanonicalTypeInternal(),
437             OmpPrivParm->getLocation(), Exprs, LParLoc);
438         CalledSignatureHelp = true;
439       }
440       Actions.ActOnInitializerError(OmpPrivParm);
441       SkipUntil(tok::r_paren, tok::annot_pragma_openmp_end, StopBeforeMatch);
442     } else {
443       // Match the ')'.
444       SourceLocation RLoc = Tok.getLocation();
445       if (!T.consumeClose())
446         RLoc = T.getCloseLocation();
447 
448       assert(!Exprs.empty() && Exprs.size() - 1 == CommaLocs.size() &&
449              "Unexpected number of commas!");
450 
451       ExprResult Initializer =
452           Actions.ActOnParenListExpr(T.getOpenLocation(), RLoc, Exprs);
453       Actions.AddInitializerToDecl(OmpPrivParm, Initializer.get(),
454                                    /*DirectInit=*/true);
455     }
456   } else if (getLangOpts().CPlusPlus11 && Tok.is(tok::l_brace)) {
457     // Parse C++0x braced-init-list.
458     Diag(Tok, diag::warn_cxx98_compat_generalized_initializer_lists);
459 
460     ExprResult Init(ParseBraceInitializer());
461 
462     if (Init.isInvalid()) {
463       Actions.ActOnInitializerError(OmpPrivParm);
464     } else {
465       Actions.AddInitializerToDecl(OmpPrivParm, Init.get(),
466                                    /*DirectInit=*/true);
467     }
468   } else {
469     Actions.ActOnUninitializedDecl(OmpPrivParm);
470   }
471 }
472 
473 namespace {
474 /// RAII that recreates function context for correct parsing of clauses of
475 /// 'declare simd' construct.
476 /// OpenMP, 2.8.2 declare simd Construct
477 /// The expressions appearing in the clauses of this directive are evaluated in
478 /// the scope of the arguments of the function declaration or definition.
479 class FNContextRAII final {
480   Parser &P;
481   Sema::CXXThisScopeRAII *ThisScope;
482   Parser::ParseScope *TempScope;
483   Parser::ParseScope *FnScope;
484   bool HasTemplateScope = false;
485   bool HasFunScope = false;
486   FNContextRAII() = delete;
487   FNContextRAII(const FNContextRAII &) = delete;
488   FNContextRAII &operator=(const FNContextRAII &) = delete;
489 
490 public:
491   FNContextRAII(Parser &P, Parser::DeclGroupPtrTy Ptr) : P(P) {
492     Decl *D = *Ptr.get().begin();
493     NamedDecl *ND = dyn_cast<NamedDecl>(D);
494     RecordDecl *RD = dyn_cast_or_null<RecordDecl>(D->getDeclContext());
495     Sema &Actions = P.getActions();
496 
497     // Allow 'this' within late-parsed attributes.
498     ThisScope = new Sema::CXXThisScopeRAII(Actions, RD, /*TypeQuals=*/0,
499                                            ND && ND->isCXXInstanceMember());
500 
501     // If the Decl is templatized, add template parameters to scope.
502     HasTemplateScope = D->isTemplateDecl();
503     TempScope =
504         new Parser::ParseScope(&P, Scope::TemplateParamScope, HasTemplateScope);
505     if (HasTemplateScope)
506       Actions.ActOnReenterTemplateScope(Actions.getCurScope(), D);
507 
508     // If the Decl is on a function, add function parameters to the scope.
509     HasFunScope = D->isFunctionOrFunctionTemplate();
510     FnScope = new Parser::ParseScope(
511         &P, Scope::FnScope | Scope::DeclScope | Scope::CompoundStmtScope,
512         HasFunScope);
513     if (HasFunScope)
514       Actions.ActOnReenterFunctionContext(Actions.getCurScope(), D);
515   }
516   ~FNContextRAII() {
517     if (HasFunScope) {
518       P.getActions().ActOnExitFunctionContext();
519       FnScope->Exit(); // Pop scope, and remove Decls from IdResolver
520     }
521     if (HasTemplateScope)
522       TempScope->Exit();
523     delete FnScope;
524     delete TempScope;
525     delete ThisScope;
526   }
527 };
528 } // namespace
529 
530 /// Parses clauses for 'declare simd' directive.
531 ///    clause:
532 ///      'inbranch' | 'notinbranch'
533 ///      'simdlen' '(' <expr> ')'
534 ///      { 'uniform' '(' <argument_list> ')' }
535 ///      { 'aligned '(' <argument_list> [ ':' <alignment> ] ')' }
536 ///      { 'linear '(' <argument_list> [ ':' <step> ] ')' }
537 static bool parseDeclareSimdClauses(
538     Parser &P, OMPDeclareSimdDeclAttr::BranchStateTy &BS, ExprResult &SimdLen,
539     SmallVectorImpl<Expr *> &Uniforms, SmallVectorImpl<Expr *> &Aligneds,
540     SmallVectorImpl<Expr *> &Alignments, SmallVectorImpl<Expr *> &Linears,
541     SmallVectorImpl<unsigned> &LinModifiers, SmallVectorImpl<Expr *> &Steps) {
542   SourceRange BSRange;
543   const Token &Tok = P.getCurToken();
544   bool IsError = false;
545   while (Tok.isNot(tok::annot_pragma_openmp_end)) {
546     if (Tok.isNot(tok::identifier))
547       break;
548     OMPDeclareSimdDeclAttr::BranchStateTy Out;
549     IdentifierInfo *II = Tok.getIdentifierInfo();
550     StringRef ClauseName = II->getName();
551     // Parse 'inranch|notinbranch' clauses.
552     if (OMPDeclareSimdDeclAttr::ConvertStrToBranchStateTy(ClauseName, Out)) {
553       if (BS != OMPDeclareSimdDeclAttr::BS_Undefined && BS != Out) {
554         P.Diag(Tok, diag::err_omp_declare_simd_inbranch_notinbranch)
555             << ClauseName
556             << OMPDeclareSimdDeclAttr::ConvertBranchStateTyToStr(BS) << BSRange;
557         IsError = true;
558       }
559       BS = Out;
560       BSRange = SourceRange(Tok.getLocation(), Tok.getEndLoc());
561       P.ConsumeToken();
562     } else if (ClauseName.equals("simdlen")) {
563       if (SimdLen.isUsable()) {
564         P.Diag(Tok, diag::err_omp_more_one_clause)
565             << getOpenMPDirectiveName(OMPD_declare_simd) << ClauseName << 0;
566         IsError = true;
567       }
568       P.ConsumeToken();
569       SourceLocation RLoc;
570       SimdLen = P.ParseOpenMPParensExpr(ClauseName, RLoc);
571       if (SimdLen.isInvalid())
572         IsError = true;
573     } else {
574       OpenMPClauseKind CKind = getOpenMPClauseKind(ClauseName);
575       if (CKind == OMPC_uniform || CKind == OMPC_aligned ||
576           CKind == OMPC_linear) {
577         Parser::OpenMPVarListDataTy Data;
578         SmallVectorImpl<Expr *> *Vars = &Uniforms;
579         if (CKind == OMPC_aligned)
580           Vars = &Aligneds;
581         else if (CKind == OMPC_linear)
582           Vars = &Linears;
583 
584         P.ConsumeToken();
585         if (P.ParseOpenMPVarList(OMPD_declare_simd,
586                                  getOpenMPClauseKind(ClauseName), *Vars, Data))
587           IsError = true;
588         if (CKind == OMPC_aligned) {
589           Alignments.append(Aligneds.size() - Alignments.size(), Data.TailExpr);
590         } else if (CKind == OMPC_linear) {
591           if (P.getActions().CheckOpenMPLinearModifier(Data.LinKind,
592                                                        Data.DepLinMapLoc))
593             Data.LinKind = OMPC_LINEAR_val;
594           LinModifiers.append(Linears.size() - LinModifiers.size(),
595                               Data.LinKind);
596           Steps.append(Linears.size() - Steps.size(), Data.TailExpr);
597         }
598       } else
599         // TODO: add parsing of other clauses.
600         break;
601     }
602     // Skip ',' if any.
603     if (Tok.is(tok::comma))
604       P.ConsumeToken();
605   }
606   return IsError;
607 }
608 
609 /// Parse clauses for '#pragma omp declare simd'.
610 Parser::DeclGroupPtrTy
611 Parser::ParseOMPDeclareSimdClauses(Parser::DeclGroupPtrTy Ptr,
612                                    CachedTokens &Toks, SourceLocation Loc) {
613   PP.EnterToken(Tok);
614   PP.EnterTokenStream(Toks, /*DisableMacroExpansion=*/true);
615   // Consume the previously pushed token.
616   ConsumeAnyToken(/*ConsumeCodeCompletionTok=*/true);
617 
618   FNContextRAII FnContext(*this, Ptr);
619   OMPDeclareSimdDeclAttr::BranchStateTy BS =
620       OMPDeclareSimdDeclAttr::BS_Undefined;
621   ExprResult Simdlen;
622   SmallVector<Expr *, 4> Uniforms;
623   SmallVector<Expr *, 4> Aligneds;
624   SmallVector<Expr *, 4> Alignments;
625   SmallVector<Expr *, 4> Linears;
626   SmallVector<unsigned, 4> LinModifiers;
627   SmallVector<Expr *, 4> Steps;
628   bool IsError =
629       parseDeclareSimdClauses(*this, BS, Simdlen, Uniforms, Aligneds,
630                               Alignments, Linears, LinModifiers, Steps);
631   // Need to check for extra tokens.
632   if (Tok.isNot(tok::annot_pragma_openmp_end)) {
633     Diag(Tok, diag::warn_omp_extra_tokens_at_eol)
634         << getOpenMPDirectiveName(OMPD_declare_simd);
635     while (Tok.isNot(tok::annot_pragma_openmp_end))
636       ConsumeAnyToken();
637   }
638   // Skip the last annot_pragma_openmp_end.
639   SourceLocation EndLoc = ConsumeAnnotationToken();
640   if (IsError)
641     return Ptr;
642   return Actions.ActOnOpenMPDeclareSimdDirective(
643       Ptr, BS, Simdlen.get(), Uniforms, Aligneds, Alignments, Linears,
644       LinModifiers, Steps, SourceRange(Loc, EndLoc));
645 }
646 
647 Parser::DeclGroupPtrTy Parser::ParseOMPDeclareTargetClauses() {
648   // OpenMP 4.5 syntax with list of entities.
649   Sema::NamedDeclSetType SameDirectiveDecls;
650   while (Tok.isNot(tok::annot_pragma_openmp_end)) {
651     OMPDeclareTargetDeclAttr::MapTypeTy MT = OMPDeclareTargetDeclAttr::MT_To;
652     if (Tok.is(tok::identifier)) {
653       IdentifierInfo *II = Tok.getIdentifierInfo();
654       StringRef ClauseName = II->getName();
655       // Parse 'to|link' clauses.
656       if (!OMPDeclareTargetDeclAttr::ConvertStrToMapTypeTy(ClauseName, MT)) {
657         Diag(Tok, diag::err_omp_declare_target_unexpected_clause) << ClauseName;
658         break;
659       }
660       ConsumeToken();
661     }
662     auto &&Callback = [this, MT, &SameDirectiveDecls](
663         CXXScopeSpec &SS, DeclarationNameInfo NameInfo) {
664       Actions.ActOnOpenMPDeclareTargetName(getCurScope(), SS, NameInfo, MT,
665                                            SameDirectiveDecls);
666     };
667     if (ParseOpenMPSimpleVarList(OMPD_declare_target, Callback,
668                                  /*AllowScopeSpecifier=*/true))
669       break;
670 
671     // Consume optional ','.
672     if (Tok.is(tok::comma))
673       ConsumeToken();
674   }
675   SkipUntil(tok::annot_pragma_openmp_end, StopBeforeMatch);
676   ConsumeAnyToken();
677   SmallVector<Decl *, 4> Decls(SameDirectiveDecls.begin(),
678                                SameDirectiveDecls.end());
679   if (Decls.empty())
680     return DeclGroupPtrTy();
681   return Actions.BuildDeclaratorGroup(Decls);
682 }
683 
684 void Parser::ParseOMPEndDeclareTargetDirective(OpenMPDirectiveKind DKind,
685                                                SourceLocation DTLoc) {
686   if (DKind != OMPD_end_declare_target) {
687     Diag(Tok, diag::err_expected_end_declare_target);
688     Diag(DTLoc, diag::note_matching) << "'#pragma omp declare target'";
689     return;
690   }
691   ConsumeAnyToken();
692   if (Tok.isNot(tok::annot_pragma_openmp_end)) {
693     Diag(Tok, diag::warn_omp_extra_tokens_at_eol)
694         << getOpenMPDirectiveName(OMPD_end_declare_target);
695     SkipUntil(tok::annot_pragma_openmp_end, StopBeforeMatch);
696   }
697   // Skip the last annot_pragma_openmp_end.
698   ConsumeAnyToken();
699 }
700 
701 /// Parsing of declarative OpenMP directives.
702 ///
703 ///       threadprivate-directive:
704 ///         annot_pragma_openmp 'threadprivate' simple-variable-list
705 ///         annot_pragma_openmp_end
706 ///
707 ///       declare-reduction-directive:
708 ///        annot_pragma_openmp 'declare' 'reduction' [...]
709 ///        annot_pragma_openmp_end
710 ///
711 ///       declare-simd-directive:
712 ///         annot_pragma_openmp 'declare simd' {<clause> [,]}
713 ///         annot_pragma_openmp_end
714 ///         <function declaration/definition>
715 ///
716 ///       requires directive:
717 ///         annot_pragma_openmp 'requires' <clause> [[[,] <clause>] ... ]
718 ///         annot_pragma_openmp_end
719 ///
720 Parser::DeclGroupPtrTy Parser::ParseOpenMPDeclarativeDirectiveWithExtDecl(
721     AccessSpecifier &AS, ParsedAttributesWithRange &Attrs,
722     DeclSpec::TST TagType, Decl *Tag) {
723   assert(Tok.is(tok::annot_pragma_openmp) && "Not an OpenMP directive!");
724   ParenBraceBracketBalancer BalancerRAIIObj(*this);
725 
726   SourceLocation Loc = ConsumeAnnotationToken();
727   OpenMPDirectiveKind DKind = parseOpenMPDirectiveKind(*this);
728 
729   switch (DKind) {
730   case OMPD_threadprivate: {
731     ConsumeToken();
732     ThreadprivateListParserHelper Helper(this);
733     if (!ParseOpenMPSimpleVarList(OMPD_threadprivate, Helper, true)) {
734       // The last seen token is annot_pragma_openmp_end - need to check for
735       // extra tokens.
736       if (Tok.isNot(tok::annot_pragma_openmp_end)) {
737         Diag(Tok, diag::warn_omp_extra_tokens_at_eol)
738             << getOpenMPDirectiveName(OMPD_threadprivate);
739         SkipUntil(tok::annot_pragma_openmp_end, StopBeforeMatch);
740       }
741       // Skip the last annot_pragma_openmp_end.
742       ConsumeAnnotationToken();
743       return Actions.ActOnOpenMPThreadprivateDirective(Loc,
744                                                        Helper.getIdentifiers());
745     }
746     break;
747   }
748   case OMPD_requires: {
749     SourceLocation StartLoc = ConsumeToken();
750     SmallVector<OMPClause *, 5> Clauses;
751     SmallVector<llvm::PointerIntPair<OMPClause *, 1, bool>, OMPC_unknown + 1>
752     FirstClauses(OMPC_unknown + 1);
753     if (Tok.is(tok::annot_pragma_openmp_end)) {
754       Diag(Tok, diag::err_omp_expected_clause)
755           << getOpenMPDirectiveName(OMPD_requires);
756       break;
757     }
758     while (Tok.isNot(tok::annot_pragma_openmp_end)) {
759       OpenMPClauseKind CKind = Tok.isAnnotation()
760                                    ? OMPC_unknown
761                                    : getOpenMPClauseKind(PP.getSpelling(Tok));
762       Actions.StartOpenMPClause(CKind);
763       OMPClause *Clause =
764           ParseOpenMPClause(OMPD_requires, CKind, !FirstClauses[CKind].getInt());
765       SkipUntil(tok::comma, tok::identifier, tok::annot_pragma_openmp_end, StopBeforeMatch);
766       FirstClauses[CKind].setInt(true);
767       if (Clause != nullptr)
768         Clauses.push_back(Clause);
769       if (Tok.is(tok::annot_pragma_openmp_end)) {
770         Actions.EndOpenMPClause();
771         break;
772       }
773       // Skip ',' if any.
774       if (Tok.is(tok::comma))
775         ConsumeToken();
776       Actions.EndOpenMPClause();
777     }
778     // Consume final annot_pragma_openmp_end
779     if (Clauses.size() == 0) {
780       Diag(Tok, diag::err_omp_expected_clause)
781           << getOpenMPDirectiveName(OMPD_requires);
782       ConsumeAnnotationToken();
783       return nullptr;
784     }
785     ConsumeAnnotationToken();
786     return Actions.ActOnOpenMPRequiresDirective(StartLoc, Clauses);
787   }
788   case OMPD_declare_reduction:
789     ConsumeToken();
790     if (DeclGroupPtrTy Res = ParseOpenMPDeclareReductionDirective(AS)) {
791       // The last seen token is annot_pragma_openmp_end - need to check for
792       // extra tokens.
793       if (Tok.isNot(tok::annot_pragma_openmp_end)) {
794         Diag(Tok, diag::warn_omp_extra_tokens_at_eol)
795             << getOpenMPDirectiveName(OMPD_declare_reduction);
796         while (Tok.isNot(tok::annot_pragma_openmp_end))
797           ConsumeAnyToken();
798       }
799       // Skip the last annot_pragma_openmp_end.
800       ConsumeAnnotationToken();
801       return Res;
802     }
803     break;
804   case OMPD_declare_simd: {
805     // The syntax is:
806     // { #pragma omp declare simd }
807     // <function-declaration-or-definition>
808     //
809     ConsumeToken();
810     CachedTokens Toks;
811     while(Tok.isNot(tok::annot_pragma_openmp_end)) {
812       Toks.push_back(Tok);
813       ConsumeAnyToken();
814     }
815     Toks.push_back(Tok);
816     ConsumeAnyToken();
817 
818     DeclGroupPtrTy Ptr;
819     if (Tok.is(tok::annot_pragma_openmp)) {
820       Ptr = ParseOpenMPDeclarativeDirectiveWithExtDecl(AS, Attrs, TagType, Tag);
821     } else if (Tok.isNot(tok::r_brace) && !isEofOrEom()) {
822       // Here we expect to see some function declaration.
823       if (AS == AS_none) {
824         assert(TagType == DeclSpec::TST_unspecified);
825         MaybeParseCXX11Attributes(Attrs);
826         ParsingDeclSpec PDS(*this);
827         Ptr = ParseExternalDeclaration(Attrs, &PDS);
828       } else {
829         Ptr =
830             ParseCXXClassMemberDeclarationWithPragmas(AS, Attrs, TagType, Tag);
831       }
832     }
833     if (!Ptr) {
834       Diag(Loc, diag::err_omp_decl_in_declare_simd);
835       return DeclGroupPtrTy();
836     }
837     return ParseOMPDeclareSimdClauses(Ptr, Toks, Loc);
838   }
839   case OMPD_declare_target: {
840     SourceLocation DTLoc = ConsumeAnyToken();
841     if (Tok.isNot(tok::annot_pragma_openmp_end)) {
842       return ParseOMPDeclareTargetClauses();
843     }
844 
845     // Skip the last annot_pragma_openmp_end.
846     ConsumeAnyToken();
847 
848     if (!Actions.ActOnStartOpenMPDeclareTargetDirective(DTLoc))
849       return DeclGroupPtrTy();
850 
851     llvm::SmallVector<Decl *, 4>  Decls;
852     DKind = parseOpenMPDirectiveKind(*this);
853     while (DKind != OMPD_end_declare_target && Tok.isNot(tok::eof) &&
854            Tok.isNot(tok::r_brace)) {
855       DeclGroupPtrTy Ptr;
856       // Here we expect to see some function declaration.
857       if (AS == AS_none) {
858         assert(TagType == DeclSpec::TST_unspecified);
859         MaybeParseCXX11Attributes(Attrs);
860         ParsingDeclSpec PDS(*this);
861         Ptr = ParseExternalDeclaration(Attrs, &PDS);
862       } else {
863         Ptr =
864             ParseCXXClassMemberDeclarationWithPragmas(AS, Attrs, TagType, Tag);
865       }
866       if (Ptr) {
867         DeclGroupRef Ref = Ptr.get();
868         Decls.append(Ref.begin(), Ref.end());
869       }
870       if (Tok.isAnnotation() && Tok.is(tok::annot_pragma_openmp)) {
871         TentativeParsingAction TPA(*this);
872         ConsumeAnnotationToken();
873         DKind = parseOpenMPDirectiveKind(*this);
874         if (DKind != OMPD_end_declare_target)
875           TPA.Revert();
876         else
877           TPA.Commit();
878       }
879     }
880 
881     ParseOMPEndDeclareTargetDirective(DKind, DTLoc);
882     Actions.ActOnFinishOpenMPDeclareTargetDirective();
883     return Actions.BuildDeclaratorGroup(Decls);
884   }
885   case OMPD_unknown:
886     Diag(Tok, diag::err_omp_unknown_directive);
887     break;
888   case OMPD_parallel:
889   case OMPD_simd:
890   case OMPD_task:
891   case OMPD_taskyield:
892   case OMPD_barrier:
893   case OMPD_taskwait:
894   case OMPD_taskgroup:
895   case OMPD_flush:
896   case OMPD_for:
897   case OMPD_for_simd:
898   case OMPD_sections:
899   case OMPD_section:
900   case OMPD_single:
901   case OMPD_master:
902   case OMPD_ordered:
903   case OMPD_critical:
904   case OMPD_parallel_for:
905   case OMPD_parallel_for_simd:
906   case OMPD_parallel_sections:
907   case OMPD_atomic:
908   case OMPD_target:
909   case OMPD_teams:
910   case OMPD_cancellation_point:
911   case OMPD_cancel:
912   case OMPD_target_data:
913   case OMPD_target_enter_data:
914   case OMPD_target_exit_data:
915   case OMPD_target_parallel:
916   case OMPD_target_parallel_for:
917   case OMPD_taskloop:
918   case OMPD_taskloop_simd:
919   case OMPD_distribute:
920   case OMPD_end_declare_target:
921   case OMPD_target_update:
922   case OMPD_distribute_parallel_for:
923   case OMPD_distribute_parallel_for_simd:
924   case OMPD_distribute_simd:
925   case OMPD_target_parallel_for_simd:
926   case OMPD_target_simd:
927   case OMPD_teams_distribute:
928   case OMPD_teams_distribute_simd:
929   case OMPD_teams_distribute_parallel_for_simd:
930   case OMPD_teams_distribute_parallel_for:
931   case OMPD_target_teams:
932   case OMPD_target_teams_distribute:
933   case OMPD_target_teams_distribute_parallel_for:
934   case OMPD_target_teams_distribute_parallel_for_simd:
935   case OMPD_target_teams_distribute_simd:
936     Diag(Tok, diag::err_omp_unexpected_directive)
937         << 1 << getOpenMPDirectiveName(DKind);
938     break;
939   }
940   while (Tok.isNot(tok::annot_pragma_openmp_end))
941     ConsumeAnyToken();
942   ConsumeAnyToken();
943   return nullptr;
944 }
945 
946 /// Parsing of declarative or executable OpenMP directives.
947 ///
948 ///       threadprivate-directive:
949 ///         annot_pragma_openmp 'threadprivate' simple-variable-list
950 ///         annot_pragma_openmp_end
951 ///
952 ///       declare-reduction-directive:
953 ///         annot_pragma_openmp 'declare' 'reduction' '(' <reduction_id> ':'
954 ///         <type> {',' <type>} ':' <expression> ')' ['initializer' '('
955 ///         ('omp_priv' '=' <expression>|<function_call>) ')']
956 ///         annot_pragma_openmp_end
957 ///
958 ///       executable-directive:
959 ///         annot_pragma_openmp 'parallel' | 'simd' | 'for' | 'sections' |
960 ///         'section' | 'single' | 'master' | 'critical' [ '(' <name> ')' ] |
961 ///         'parallel for' | 'parallel sections' | 'task' | 'taskyield' |
962 ///         'barrier' | 'taskwait' | 'flush' | 'ordered' | 'atomic' |
963 ///         'for simd' | 'parallel for simd' | 'target' | 'target data' |
964 ///         'taskgroup' | 'teams' | 'taskloop' | 'taskloop simd' |
965 ///         'distribute' | 'target enter data' | 'target exit data' |
966 ///         'target parallel' | 'target parallel for' |
967 ///         'target update' | 'distribute parallel for' |
968 ///         'distribute paralle for simd' | 'distribute simd' |
969 ///         'target parallel for simd' | 'target simd' |
970 ///         'teams distribute' | 'teams distribute simd' |
971 ///         'teams distribute parallel for simd' |
972 ///         'teams distribute parallel for' | 'target teams' |
973 ///         'target teams distribute' |
974 ///         'target teams distribute parallel for' |
975 ///         'target teams distribute parallel for simd' |
976 ///         'target teams distribute simd' {clause}
977 ///         annot_pragma_openmp_end
978 ///
979 StmtResult Parser::ParseOpenMPDeclarativeOrExecutableDirective(
980     AllowedConstructsKind Allowed) {
981   assert(Tok.is(tok::annot_pragma_openmp) && "Not an OpenMP directive!");
982   ParenBraceBracketBalancer BalancerRAIIObj(*this);
983   SmallVector<OMPClause *, 5> Clauses;
984   SmallVector<llvm::PointerIntPair<OMPClause *, 1, bool>, OMPC_unknown + 1>
985   FirstClauses(OMPC_unknown + 1);
986   unsigned ScopeFlags = Scope::FnScope | Scope::DeclScope |
987                         Scope::CompoundStmtScope | Scope::OpenMPDirectiveScope;
988   SourceLocation Loc = ConsumeAnnotationToken(), EndLoc;
989   OpenMPDirectiveKind DKind = parseOpenMPDirectiveKind(*this);
990   OpenMPDirectiveKind CancelRegion = OMPD_unknown;
991   // Name of critical directive.
992   DeclarationNameInfo DirName;
993   StmtResult Directive = StmtError();
994   bool HasAssociatedStatement = true;
995   bool FlushHasClause = false;
996 
997   switch (DKind) {
998   case OMPD_threadprivate: {
999     if (Allowed != ACK_Any) {
1000       Diag(Tok, diag::err_omp_immediate_directive)
1001           << getOpenMPDirectiveName(DKind) << 0;
1002     }
1003     ConsumeToken();
1004     ThreadprivateListParserHelper Helper(this);
1005     if (!ParseOpenMPSimpleVarList(OMPD_threadprivate, Helper, false)) {
1006       // The last seen token is annot_pragma_openmp_end - need to check for
1007       // extra tokens.
1008       if (Tok.isNot(tok::annot_pragma_openmp_end)) {
1009         Diag(Tok, diag::warn_omp_extra_tokens_at_eol)
1010             << getOpenMPDirectiveName(OMPD_threadprivate);
1011         SkipUntil(tok::annot_pragma_openmp_end, StopBeforeMatch);
1012       }
1013       DeclGroupPtrTy Res = Actions.ActOnOpenMPThreadprivateDirective(
1014           Loc, Helper.getIdentifiers());
1015       Directive = Actions.ActOnDeclStmt(Res, Loc, Tok.getLocation());
1016     }
1017     SkipUntil(tok::annot_pragma_openmp_end);
1018     break;
1019   }
1020   case OMPD_declare_reduction:
1021     ConsumeToken();
1022     if (DeclGroupPtrTy Res =
1023             ParseOpenMPDeclareReductionDirective(/*AS=*/AS_none)) {
1024       // The last seen token is annot_pragma_openmp_end - need to check for
1025       // extra tokens.
1026       if (Tok.isNot(tok::annot_pragma_openmp_end)) {
1027         Diag(Tok, diag::warn_omp_extra_tokens_at_eol)
1028             << getOpenMPDirectiveName(OMPD_declare_reduction);
1029         while (Tok.isNot(tok::annot_pragma_openmp_end))
1030           ConsumeAnyToken();
1031       }
1032       ConsumeAnyToken();
1033       Directive = Actions.ActOnDeclStmt(Res, Loc, Tok.getLocation());
1034     } else {
1035       SkipUntil(tok::annot_pragma_openmp_end);
1036     }
1037     break;
1038   case OMPD_flush:
1039     if (PP.LookAhead(0).is(tok::l_paren)) {
1040       FlushHasClause = true;
1041       // Push copy of the current token back to stream to properly parse
1042       // pseudo-clause OMPFlushClause.
1043       PP.EnterToken(Tok);
1044     }
1045     LLVM_FALLTHROUGH;
1046   case OMPD_taskyield:
1047   case OMPD_barrier:
1048   case OMPD_taskwait:
1049   case OMPD_cancellation_point:
1050   case OMPD_cancel:
1051   case OMPD_target_enter_data:
1052   case OMPD_target_exit_data:
1053   case OMPD_target_update:
1054     if (Allowed == ACK_StatementsOpenMPNonStandalone) {
1055       Diag(Tok, diag::err_omp_immediate_directive)
1056           << getOpenMPDirectiveName(DKind) << 0;
1057     }
1058     HasAssociatedStatement = false;
1059     // Fall through for further analysis.
1060     LLVM_FALLTHROUGH;
1061   case OMPD_parallel:
1062   case OMPD_simd:
1063   case OMPD_for:
1064   case OMPD_for_simd:
1065   case OMPD_sections:
1066   case OMPD_single:
1067   case OMPD_section:
1068   case OMPD_master:
1069   case OMPD_critical:
1070   case OMPD_parallel_for:
1071   case OMPD_parallel_for_simd:
1072   case OMPD_parallel_sections:
1073   case OMPD_task:
1074   case OMPD_ordered:
1075   case OMPD_atomic:
1076   case OMPD_target:
1077   case OMPD_teams:
1078   case OMPD_taskgroup:
1079   case OMPD_target_data:
1080   case OMPD_target_parallel:
1081   case OMPD_target_parallel_for:
1082   case OMPD_taskloop:
1083   case OMPD_taskloop_simd:
1084   case OMPD_distribute:
1085   case OMPD_distribute_parallel_for:
1086   case OMPD_distribute_parallel_for_simd:
1087   case OMPD_distribute_simd:
1088   case OMPD_target_parallel_for_simd:
1089   case OMPD_target_simd:
1090   case OMPD_teams_distribute:
1091   case OMPD_teams_distribute_simd:
1092   case OMPD_teams_distribute_parallel_for_simd:
1093   case OMPD_teams_distribute_parallel_for:
1094   case OMPD_target_teams:
1095   case OMPD_target_teams_distribute:
1096   case OMPD_target_teams_distribute_parallel_for:
1097   case OMPD_target_teams_distribute_parallel_for_simd:
1098   case OMPD_target_teams_distribute_simd: {
1099     ConsumeToken();
1100     // Parse directive name of the 'critical' directive if any.
1101     if (DKind == OMPD_critical) {
1102       BalancedDelimiterTracker T(*this, tok::l_paren,
1103                                  tok::annot_pragma_openmp_end);
1104       if (!T.consumeOpen()) {
1105         if (Tok.isAnyIdentifier()) {
1106           DirName =
1107               DeclarationNameInfo(Tok.getIdentifierInfo(), Tok.getLocation());
1108           ConsumeAnyToken();
1109         } else {
1110           Diag(Tok, diag::err_omp_expected_identifier_for_critical);
1111         }
1112         T.consumeClose();
1113       }
1114     } else if (DKind == OMPD_cancellation_point || DKind == OMPD_cancel) {
1115       CancelRegion = parseOpenMPDirectiveKind(*this);
1116       if (Tok.isNot(tok::annot_pragma_openmp_end))
1117         ConsumeToken();
1118     }
1119 
1120     if (isOpenMPLoopDirective(DKind))
1121       ScopeFlags |= Scope::OpenMPLoopDirectiveScope;
1122     if (isOpenMPSimdDirective(DKind))
1123       ScopeFlags |= Scope::OpenMPSimdDirectiveScope;
1124     ParseScope OMPDirectiveScope(this, ScopeFlags);
1125     Actions.StartOpenMPDSABlock(DKind, DirName, Actions.getCurScope(), Loc);
1126 
1127     while (Tok.isNot(tok::annot_pragma_openmp_end)) {
1128       OpenMPClauseKind CKind =
1129           Tok.isAnnotation()
1130               ? OMPC_unknown
1131               : FlushHasClause ? OMPC_flush
1132                                : getOpenMPClauseKind(PP.getSpelling(Tok));
1133       Actions.StartOpenMPClause(CKind);
1134       FlushHasClause = false;
1135       OMPClause *Clause =
1136           ParseOpenMPClause(DKind, CKind, !FirstClauses[CKind].getInt());
1137       FirstClauses[CKind].setInt(true);
1138       if (Clause) {
1139         FirstClauses[CKind].setPointer(Clause);
1140         Clauses.push_back(Clause);
1141       }
1142 
1143       // Skip ',' if any.
1144       if (Tok.is(tok::comma))
1145         ConsumeToken();
1146       Actions.EndOpenMPClause();
1147     }
1148     // End location of the directive.
1149     EndLoc = Tok.getLocation();
1150     // Consume final annot_pragma_openmp_end.
1151     ConsumeAnnotationToken();
1152 
1153     // OpenMP [2.13.8, ordered Construct, Syntax]
1154     // If the depend clause is specified, the ordered construct is a stand-alone
1155     // directive.
1156     if (DKind == OMPD_ordered && FirstClauses[OMPC_depend].getInt()) {
1157       if (Allowed == ACK_StatementsOpenMPNonStandalone) {
1158         Diag(Loc, diag::err_omp_immediate_directive)
1159             << getOpenMPDirectiveName(DKind) << 1
1160             << getOpenMPClauseName(OMPC_depend);
1161       }
1162       HasAssociatedStatement = false;
1163     }
1164 
1165     StmtResult AssociatedStmt;
1166     if (HasAssociatedStatement) {
1167       // The body is a block scope like in Lambdas and Blocks.
1168       Actions.ActOnOpenMPRegionStart(DKind, getCurScope());
1169       // FIXME: We create a bogus CompoundStmt scope to hold the contents of
1170       // the captured region. Code elsewhere assumes that any FunctionScopeInfo
1171       // should have at least one compound statement scope within it.
1172       AssociatedStmt = (Sema::CompoundScopeRAII(Actions), ParseStatement());
1173       AssociatedStmt = Actions.ActOnOpenMPRegionEnd(AssociatedStmt, Clauses);
1174     } else if (DKind == OMPD_target_update || DKind == OMPD_target_enter_data ||
1175                DKind == OMPD_target_exit_data) {
1176       Actions.ActOnOpenMPRegionStart(DKind, getCurScope());
1177       AssociatedStmt = (Sema::CompoundScopeRAII(Actions),
1178                         Actions.ActOnCompoundStmt(Loc, Loc, llvm::None,
1179                                                   /*isStmtExpr=*/false));
1180       AssociatedStmt = Actions.ActOnOpenMPRegionEnd(AssociatedStmt, Clauses);
1181     }
1182     Directive = Actions.ActOnOpenMPExecutableDirective(
1183         DKind, DirName, CancelRegion, Clauses, AssociatedStmt.get(), Loc,
1184         EndLoc);
1185 
1186     // Exit scope.
1187     Actions.EndOpenMPDSABlock(Directive.get());
1188     OMPDirectiveScope.Exit();
1189     break;
1190   }
1191   case OMPD_declare_simd:
1192   case OMPD_declare_target:
1193   case OMPD_end_declare_target:
1194   case OMPD_requires:
1195     Diag(Tok, diag::err_omp_unexpected_directive)
1196         << 1 << getOpenMPDirectiveName(DKind);
1197     SkipUntil(tok::annot_pragma_openmp_end);
1198     break;
1199   case OMPD_unknown:
1200     Diag(Tok, diag::err_omp_unknown_directive);
1201     SkipUntil(tok::annot_pragma_openmp_end);
1202     break;
1203   }
1204   return Directive;
1205 }
1206 
1207 // Parses simple list:
1208 //   simple-variable-list:
1209 //         '(' id-expression {, id-expression} ')'
1210 //
1211 bool Parser::ParseOpenMPSimpleVarList(
1212     OpenMPDirectiveKind Kind,
1213     const llvm::function_ref<void(CXXScopeSpec &, DeclarationNameInfo)> &
1214         Callback,
1215     bool AllowScopeSpecifier) {
1216   // Parse '('.
1217   BalancedDelimiterTracker T(*this, tok::l_paren, tok::annot_pragma_openmp_end);
1218   if (T.expectAndConsume(diag::err_expected_lparen_after,
1219                          getOpenMPDirectiveName(Kind)))
1220     return true;
1221   bool IsCorrect = true;
1222   bool NoIdentIsFound = true;
1223 
1224   // Read tokens while ')' or annot_pragma_openmp_end is not found.
1225   while (Tok.isNot(tok::r_paren) && Tok.isNot(tok::annot_pragma_openmp_end)) {
1226     CXXScopeSpec SS;
1227     UnqualifiedId Name;
1228     // Read var name.
1229     Token PrevTok = Tok;
1230     NoIdentIsFound = false;
1231 
1232     if (AllowScopeSpecifier && getLangOpts().CPlusPlus &&
1233         ParseOptionalCXXScopeSpecifier(SS, nullptr, false)) {
1234       IsCorrect = false;
1235       SkipUntil(tok::comma, tok::r_paren, tok::annot_pragma_openmp_end,
1236                 StopBeforeMatch);
1237     } else if (ParseUnqualifiedId(SS, false, false, false, false, nullptr,
1238                                   nullptr, Name)) {
1239       IsCorrect = false;
1240       SkipUntil(tok::comma, tok::r_paren, tok::annot_pragma_openmp_end,
1241                 StopBeforeMatch);
1242     } else if (Tok.isNot(tok::comma) && Tok.isNot(tok::r_paren) &&
1243                Tok.isNot(tok::annot_pragma_openmp_end)) {
1244       IsCorrect = false;
1245       SkipUntil(tok::comma, tok::r_paren, tok::annot_pragma_openmp_end,
1246                 StopBeforeMatch);
1247       Diag(PrevTok.getLocation(), diag::err_expected)
1248           << tok::identifier
1249           << SourceRange(PrevTok.getLocation(), PrevTokLocation);
1250     } else {
1251       Callback(SS, Actions.GetNameFromUnqualifiedId(Name));
1252     }
1253     // Consume ','.
1254     if (Tok.is(tok::comma)) {
1255       ConsumeToken();
1256     }
1257   }
1258 
1259   if (NoIdentIsFound) {
1260     Diag(Tok, diag::err_expected) << tok::identifier;
1261     IsCorrect = false;
1262   }
1263 
1264   // Parse ')'.
1265   IsCorrect = !T.consumeClose() && IsCorrect;
1266 
1267   return !IsCorrect;
1268 }
1269 
1270 /// Parsing of OpenMP clauses.
1271 ///
1272 ///    clause:
1273 ///       if-clause | final-clause | num_threads-clause | safelen-clause |
1274 ///       default-clause | private-clause | firstprivate-clause | shared-clause
1275 ///       | linear-clause | aligned-clause | collapse-clause |
1276 ///       lastprivate-clause | reduction-clause | proc_bind-clause |
1277 ///       schedule-clause | copyin-clause | copyprivate-clause | untied-clause |
1278 ///       mergeable-clause | flush-clause | read-clause | write-clause |
1279 ///       update-clause | capture-clause | seq_cst-clause | device-clause |
1280 ///       simdlen-clause | threads-clause | simd-clause | num_teams-clause |
1281 ///       thread_limit-clause | priority-clause | grainsize-clause |
1282 ///       nogroup-clause | num_tasks-clause | hint-clause | to-clause |
1283 ///       from-clause | is_device_ptr-clause | task_reduction-clause |
1284 ///       in_reduction-clause
1285 ///
1286 OMPClause *Parser::ParseOpenMPClause(OpenMPDirectiveKind DKind,
1287                                      OpenMPClauseKind CKind, bool FirstClause) {
1288   OMPClause *Clause = nullptr;
1289   bool ErrorFound = false;
1290   bool WrongDirective = false;
1291   // Check if clause is allowed for the given directive.
1292   if (CKind != OMPC_unknown && !isAllowedClauseForDirective(DKind, CKind)) {
1293     Diag(Tok, diag::err_omp_unexpected_clause) << getOpenMPClauseName(CKind)
1294                                                << getOpenMPDirectiveName(DKind);
1295     ErrorFound = true;
1296     WrongDirective = true;
1297   }
1298 
1299   switch (CKind) {
1300   case OMPC_final:
1301   case OMPC_num_threads:
1302   case OMPC_safelen:
1303   case OMPC_simdlen:
1304   case OMPC_collapse:
1305   case OMPC_ordered:
1306   case OMPC_device:
1307   case OMPC_num_teams:
1308   case OMPC_thread_limit:
1309   case OMPC_priority:
1310   case OMPC_grainsize:
1311   case OMPC_num_tasks:
1312   case OMPC_hint:
1313     // OpenMP [2.5, Restrictions]
1314     //  At most one num_threads clause can appear on the directive.
1315     // OpenMP [2.8.1, simd construct, Restrictions]
1316     //  Only one safelen  clause can appear on a simd directive.
1317     //  Only one simdlen  clause can appear on a simd directive.
1318     //  Only one collapse clause can appear on a simd directive.
1319     // OpenMP [2.9.1, target data construct, Restrictions]
1320     //  At most one device clause can appear on the directive.
1321     // OpenMP [2.11.1, task Construct, Restrictions]
1322     //  At most one if clause can appear on the directive.
1323     //  At most one final clause can appear on the directive.
1324     // OpenMP [teams Construct, Restrictions]
1325     //  At most one num_teams clause can appear on the directive.
1326     //  At most one thread_limit clause can appear on the directive.
1327     // OpenMP [2.9.1, task Construct, Restrictions]
1328     // At most one priority clause can appear on the directive.
1329     // OpenMP [2.9.2, taskloop Construct, Restrictions]
1330     // At most one grainsize clause can appear on the directive.
1331     // OpenMP [2.9.2, taskloop Construct, Restrictions]
1332     // At most one num_tasks clause can appear on the directive.
1333     if (!FirstClause) {
1334       Diag(Tok, diag::err_omp_more_one_clause)
1335           << getOpenMPDirectiveName(DKind) << getOpenMPClauseName(CKind) << 0;
1336       ErrorFound = true;
1337     }
1338 
1339     if (CKind == OMPC_ordered && PP.LookAhead(/*N=*/0).isNot(tok::l_paren))
1340       Clause = ParseOpenMPClause(CKind, WrongDirective);
1341     else
1342       Clause = ParseOpenMPSingleExprClause(CKind, WrongDirective);
1343     break;
1344   case OMPC_default:
1345   case OMPC_proc_bind:
1346   case OMPC_atomic_default_mem_order:
1347     // OpenMP [2.14.3.1, Restrictions]
1348     //  Only a single default clause may be specified on a parallel, task or
1349     //  teams directive.
1350     // OpenMP [2.5, parallel Construct, Restrictions]
1351     //  At most one proc_bind clause can appear on the directive.
1352     // OpenMP [5.0, Requires directive, Restrictions]
1353     //  At most one atomic_default_mem_order clause can appear
1354     //  on the directive
1355     if (!FirstClause) {
1356       Diag(Tok, diag::err_omp_more_one_clause)
1357           << getOpenMPDirectiveName(DKind) << getOpenMPClauseName(CKind) << 0;
1358       ErrorFound = true;
1359     }
1360 
1361     Clause = ParseOpenMPSimpleClause(CKind, WrongDirective);
1362     break;
1363   case OMPC_schedule:
1364   case OMPC_dist_schedule:
1365   case OMPC_defaultmap:
1366     // OpenMP [2.7.1, Restrictions, p. 3]
1367     //  Only one schedule clause can appear on a loop directive.
1368     // OpenMP [2.10.4, Restrictions, p. 106]
1369     //  At most one defaultmap clause can appear on the directive.
1370     if (!FirstClause) {
1371       Diag(Tok, diag::err_omp_more_one_clause)
1372           << getOpenMPDirectiveName(DKind) << getOpenMPClauseName(CKind) << 0;
1373       ErrorFound = true;
1374     }
1375     LLVM_FALLTHROUGH;
1376 
1377   case OMPC_if:
1378     Clause = ParseOpenMPSingleExprWithArgClause(CKind, WrongDirective);
1379     break;
1380   case OMPC_nowait:
1381   case OMPC_untied:
1382   case OMPC_mergeable:
1383   case OMPC_read:
1384   case OMPC_write:
1385   case OMPC_update:
1386   case OMPC_capture:
1387   case OMPC_seq_cst:
1388   case OMPC_threads:
1389   case OMPC_simd:
1390   case OMPC_nogroup:
1391   case OMPC_unified_address:
1392   case OMPC_unified_shared_memory:
1393   case OMPC_reverse_offload:
1394   case OMPC_dynamic_allocators:
1395     // OpenMP [2.7.1, Restrictions, p. 9]
1396     //  Only one ordered clause can appear on a loop directive.
1397     // OpenMP [2.7.1, Restrictions, C/C++, p. 4]
1398     //  Only one nowait clause can appear on a for directive.
1399     // OpenMP [5.0, Requires directive, Restrictions]
1400     //   Each of the requires clauses can appear at most once on the directive.
1401     if (!FirstClause) {
1402       Diag(Tok, diag::err_omp_more_one_clause)
1403           << getOpenMPDirectiveName(DKind) << getOpenMPClauseName(CKind) << 0;
1404       ErrorFound = true;
1405     }
1406 
1407     Clause = ParseOpenMPClause(CKind, WrongDirective);
1408     break;
1409   case OMPC_private:
1410   case OMPC_firstprivate:
1411   case OMPC_lastprivate:
1412   case OMPC_shared:
1413   case OMPC_reduction:
1414   case OMPC_task_reduction:
1415   case OMPC_in_reduction:
1416   case OMPC_linear:
1417   case OMPC_aligned:
1418   case OMPC_copyin:
1419   case OMPC_copyprivate:
1420   case OMPC_flush:
1421   case OMPC_depend:
1422   case OMPC_map:
1423   case OMPC_to:
1424   case OMPC_from:
1425   case OMPC_use_device_ptr:
1426   case OMPC_is_device_ptr:
1427     Clause = ParseOpenMPVarListClause(DKind, CKind, WrongDirective);
1428     break;
1429   case OMPC_unknown:
1430     Diag(Tok, diag::warn_omp_extra_tokens_at_eol)
1431         << getOpenMPDirectiveName(DKind);
1432     SkipUntil(tok::annot_pragma_openmp_end, StopBeforeMatch);
1433     break;
1434   case OMPC_threadprivate:
1435   case OMPC_uniform:
1436     if (!WrongDirective)
1437       Diag(Tok, diag::err_omp_unexpected_clause)
1438           << getOpenMPClauseName(CKind) << getOpenMPDirectiveName(DKind);
1439     SkipUntil(tok::comma, tok::annot_pragma_openmp_end, StopBeforeMatch);
1440     break;
1441   }
1442   return ErrorFound ? nullptr : Clause;
1443 }
1444 
1445 /// Parses simple expression in parens for single-expression clauses of OpenMP
1446 /// constructs.
1447 /// \param RLoc Returned location of right paren.
1448 ExprResult Parser::ParseOpenMPParensExpr(StringRef ClauseName,
1449                                          SourceLocation &RLoc) {
1450   BalancedDelimiterTracker T(*this, tok::l_paren, tok::annot_pragma_openmp_end);
1451   if (T.expectAndConsume(diag::err_expected_lparen_after, ClauseName.data()))
1452     return ExprError();
1453 
1454   SourceLocation ELoc = Tok.getLocation();
1455   ExprResult LHS(ParseCastExpression(
1456       /*isUnaryExpression=*/false, /*isAddressOfOperand=*/false, NotTypeCast));
1457   ExprResult Val(ParseRHSOfBinaryExpression(LHS, prec::Conditional));
1458   Val = Actions.ActOnFinishFullExpr(Val.get(), ELoc);
1459 
1460   // Parse ')'.
1461   RLoc = Tok.getLocation();
1462   if (!T.consumeClose())
1463     RLoc = T.getCloseLocation();
1464 
1465   return Val;
1466 }
1467 
1468 /// Parsing of OpenMP clauses with single expressions like 'final',
1469 /// 'collapse', 'safelen', 'num_threads', 'simdlen', 'num_teams',
1470 /// 'thread_limit', 'simdlen', 'priority', 'grainsize', 'num_tasks' or 'hint'.
1471 ///
1472 ///    final-clause:
1473 ///      'final' '(' expression ')'
1474 ///
1475 ///    num_threads-clause:
1476 ///      'num_threads' '(' expression ')'
1477 ///
1478 ///    safelen-clause:
1479 ///      'safelen' '(' expression ')'
1480 ///
1481 ///    simdlen-clause:
1482 ///      'simdlen' '(' expression ')'
1483 ///
1484 ///    collapse-clause:
1485 ///      'collapse' '(' expression ')'
1486 ///
1487 ///    priority-clause:
1488 ///      'priority' '(' expression ')'
1489 ///
1490 ///    grainsize-clause:
1491 ///      'grainsize' '(' expression ')'
1492 ///
1493 ///    num_tasks-clause:
1494 ///      'num_tasks' '(' expression ')'
1495 ///
1496 ///    hint-clause:
1497 ///      'hint' '(' expression ')'
1498 ///
1499 OMPClause *Parser::ParseOpenMPSingleExprClause(OpenMPClauseKind Kind,
1500                                                bool ParseOnly) {
1501   SourceLocation Loc = ConsumeToken();
1502   SourceLocation LLoc = Tok.getLocation();
1503   SourceLocation RLoc;
1504 
1505   ExprResult Val = ParseOpenMPParensExpr(getOpenMPClauseName(Kind), RLoc);
1506 
1507   if (Val.isInvalid())
1508     return nullptr;
1509 
1510   if (ParseOnly)
1511     return nullptr;
1512   return Actions.ActOnOpenMPSingleExprClause(Kind, Val.get(), Loc, LLoc, RLoc);
1513 }
1514 
1515 /// Parsing of simple OpenMP clauses like 'default' or 'proc_bind'.
1516 ///
1517 ///    default-clause:
1518 ///         'default' '(' 'none' | 'shared' ')
1519 ///
1520 ///    proc_bind-clause:
1521 ///         'proc_bind' '(' 'master' | 'close' | 'spread' ')
1522 ///
1523 OMPClause *Parser::ParseOpenMPSimpleClause(OpenMPClauseKind Kind,
1524                                            bool ParseOnly) {
1525   SourceLocation Loc = Tok.getLocation();
1526   SourceLocation LOpen = ConsumeToken();
1527   // Parse '('.
1528   BalancedDelimiterTracker T(*this, tok::l_paren, tok::annot_pragma_openmp_end);
1529   if (T.expectAndConsume(diag::err_expected_lparen_after,
1530                          getOpenMPClauseName(Kind)))
1531     return nullptr;
1532 
1533   unsigned Type = getOpenMPSimpleClauseType(
1534       Kind, Tok.isAnnotation() ? "" : PP.getSpelling(Tok));
1535   SourceLocation TypeLoc = Tok.getLocation();
1536   if (Tok.isNot(tok::r_paren) && Tok.isNot(tok::comma) &&
1537       Tok.isNot(tok::annot_pragma_openmp_end))
1538     ConsumeAnyToken();
1539 
1540   // Parse ')'.
1541   SourceLocation RLoc = Tok.getLocation();
1542   if (!T.consumeClose())
1543     RLoc = T.getCloseLocation();
1544 
1545   if (ParseOnly)
1546     return nullptr;
1547   return Actions.ActOnOpenMPSimpleClause(Kind, Type, TypeLoc, LOpen, Loc, RLoc);
1548 }
1549 
1550 /// Parsing of OpenMP clauses like 'ordered'.
1551 ///
1552 ///    ordered-clause:
1553 ///         'ordered'
1554 ///
1555 ///    nowait-clause:
1556 ///         'nowait'
1557 ///
1558 ///    untied-clause:
1559 ///         'untied'
1560 ///
1561 ///    mergeable-clause:
1562 ///         'mergeable'
1563 ///
1564 ///    read-clause:
1565 ///         'read'
1566 ///
1567 ///    threads-clause:
1568 ///         'threads'
1569 ///
1570 ///    simd-clause:
1571 ///         'simd'
1572 ///
1573 ///    nogroup-clause:
1574 ///         'nogroup'
1575 ///
1576 OMPClause *Parser::ParseOpenMPClause(OpenMPClauseKind Kind, bool ParseOnly) {
1577   SourceLocation Loc = Tok.getLocation();
1578   ConsumeAnyToken();
1579 
1580   if (ParseOnly)
1581     return nullptr;
1582   return Actions.ActOnOpenMPClause(Kind, Loc, Tok.getLocation());
1583 }
1584 
1585 
1586 /// Parsing of OpenMP clauses with single expressions and some additional
1587 /// argument like 'schedule' or 'dist_schedule'.
1588 ///
1589 ///    schedule-clause:
1590 ///      'schedule' '(' [ modifier [ ',' modifier ] ':' ] kind [',' expression ]
1591 ///      ')'
1592 ///
1593 ///    if-clause:
1594 ///      'if' '(' [ directive-name-modifier ':' ] expression ')'
1595 ///
1596 ///    defaultmap:
1597 ///      'defaultmap' '(' modifier ':' kind ')'
1598 ///
1599 OMPClause *Parser::ParseOpenMPSingleExprWithArgClause(OpenMPClauseKind Kind,
1600                                                       bool ParseOnly) {
1601   SourceLocation Loc = ConsumeToken();
1602   SourceLocation DelimLoc;
1603   // Parse '('.
1604   BalancedDelimiterTracker T(*this, tok::l_paren, tok::annot_pragma_openmp_end);
1605   if (T.expectAndConsume(diag::err_expected_lparen_after,
1606                          getOpenMPClauseName(Kind)))
1607     return nullptr;
1608 
1609   ExprResult Val;
1610   SmallVector<unsigned, 4> Arg;
1611   SmallVector<SourceLocation, 4> KLoc;
1612   if (Kind == OMPC_schedule) {
1613     enum { Modifier1, Modifier2, ScheduleKind, NumberOfElements };
1614     Arg.resize(NumberOfElements);
1615     KLoc.resize(NumberOfElements);
1616     Arg[Modifier1] = OMPC_SCHEDULE_MODIFIER_unknown;
1617     Arg[Modifier2] = OMPC_SCHEDULE_MODIFIER_unknown;
1618     Arg[ScheduleKind] = OMPC_SCHEDULE_unknown;
1619     unsigned KindModifier = getOpenMPSimpleClauseType(
1620         Kind, Tok.isAnnotation() ? "" : PP.getSpelling(Tok));
1621     if (KindModifier > OMPC_SCHEDULE_unknown) {
1622       // Parse 'modifier'
1623       Arg[Modifier1] = KindModifier;
1624       KLoc[Modifier1] = Tok.getLocation();
1625       if (Tok.isNot(tok::r_paren) && Tok.isNot(tok::comma) &&
1626           Tok.isNot(tok::annot_pragma_openmp_end))
1627         ConsumeAnyToken();
1628       if (Tok.is(tok::comma)) {
1629         // Parse ',' 'modifier'
1630         ConsumeAnyToken();
1631         KindModifier = getOpenMPSimpleClauseType(
1632             Kind, Tok.isAnnotation() ? "" : PP.getSpelling(Tok));
1633         Arg[Modifier2] = KindModifier > OMPC_SCHEDULE_unknown
1634                              ? KindModifier
1635                              : (unsigned)OMPC_SCHEDULE_unknown;
1636         KLoc[Modifier2] = Tok.getLocation();
1637         if (Tok.isNot(tok::r_paren) && Tok.isNot(tok::comma) &&
1638             Tok.isNot(tok::annot_pragma_openmp_end))
1639           ConsumeAnyToken();
1640       }
1641       // Parse ':'
1642       if (Tok.is(tok::colon))
1643         ConsumeAnyToken();
1644       else
1645         Diag(Tok, diag::warn_pragma_expected_colon) << "schedule modifier";
1646       KindModifier = getOpenMPSimpleClauseType(
1647           Kind, Tok.isAnnotation() ? "" : PP.getSpelling(Tok));
1648     }
1649     Arg[ScheduleKind] = KindModifier;
1650     KLoc[ScheduleKind] = Tok.getLocation();
1651     if (Tok.isNot(tok::r_paren) && Tok.isNot(tok::comma) &&
1652         Tok.isNot(tok::annot_pragma_openmp_end))
1653       ConsumeAnyToken();
1654     if ((Arg[ScheduleKind] == OMPC_SCHEDULE_static ||
1655          Arg[ScheduleKind] == OMPC_SCHEDULE_dynamic ||
1656          Arg[ScheduleKind] == OMPC_SCHEDULE_guided) &&
1657         Tok.is(tok::comma))
1658       DelimLoc = ConsumeAnyToken();
1659   } else if (Kind == OMPC_dist_schedule) {
1660     Arg.push_back(getOpenMPSimpleClauseType(
1661         Kind, Tok.isAnnotation() ? "" : PP.getSpelling(Tok)));
1662     KLoc.push_back(Tok.getLocation());
1663     if (Tok.isNot(tok::r_paren) && Tok.isNot(tok::comma) &&
1664         Tok.isNot(tok::annot_pragma_openmp_end))
1665       ConsumeAnyToken();
1666     if (Arg.back() == OMPC_DIST_SCHEDULE_static && Tok.is(tok::comma))
1667       DelimLoc = ConsumeAnyToken();
1668   } else if (Kind == OMPC_defaultmap) {
1669     // Get a defaultmap modifier
1670     Arg.push_back(getOpenMPSimpleClauseType(
1671         Kind, Tok.isAnnotation() ? "" : PP.getSpelling(Tok)));
1672     KLoc.push_back(Tok.getLocation());
1673     if (Tok.isNot(tok::r_paren) && Tok.isNot(tok::comma) &&
1674         Tok.isNot(tok::annot_pragma_openmp_end))
1675       ConsumeAnyToken();
1676     // Parse ':'
1677     if (Tok.is(tok::colon))
1678       ConsumeAnyToken();
1679     else if (Arg.back() != OMPC_DEFAULTMAP_MODIFIER_unknown)
1680       Diag(Tok, diag::warn_pragma_expected_colon) << "defaultmap modifier";
1681     // Get a defaultmap kind
1682     Arg.push_back(getOpenMPSimpleClauseType(
1683         Kind, Tok.isAnnotation() ? "" : PP.getSpelling(Tok)));
1684     KLoc.push_back(Tok.getLocation());
1685     if (Tok.isNot(tok::r_paren) && Tok.isNot(tok::comma) &&
1686         Tok.isNot(tok::annot_pragma_openmp_end))
1687       ConsumeAnyToken();
1688   } else {
1689     assert(Kind == OMPC_if);
1690     KLoc.push_back(Tok.getLocation());
1691     TentativeParsingAction TPA(*this);
1692     Arg.push_back(parseOpenMPDirectiveKind(*this));
1693     if (Arg.back() != OMPD_unknown) {
1694       ConsumeToken();
1695       if (Tok.is(tok::colon) && getLangOpts().OpenMP > 40) {
1696         TPA.Commit();
1697         DelimLoc = ConsumeToken();
1698       } else {
1699         TPA.Revert();
1700         Arg.back() = OMPD_unknown;
1701       }
1702     } else {
1703       TPA.Revert();
1704     }
1705   }
1706 
1707   bool NeedAnExpression = (Kind == OMPC_schedule && DelimLoc.isValid()) ||
1708                           (Kind == OMPC_dist_schedule && DelimLoc.isValid()) ||
1709                           Kind == OMPC_if;
1710   if (NeedAnExpression) {
1711     SourceLocation ELoc = Tok.getLocation();
1712     ExprResult LHS(ParseCastExpression(false, false, NotTypeCast));
1713     Val = ParseRHSOfBinaryExpression(LHS, prec::Conditional);
1714     Val = Actions.ActOnFinishFullExpr(Val.get(), ELoc);
1715   }
1716 
1717   // Parse ')'.
1718   SourceLocation RLoc = Tok.getLocation();
1719   if (!T.consumeClose())
1720     RLoc = T.getCloseLocation();
1721 
1722   if (NeedAnExpression && Val.isInvalid())
1723     return nullptr;
1724 
1725   if (ParseOnly)
1726     return nullptr;
1727   return Actions.ActOnOpenMPSingleExprWithArgClause(
1728       Kind, Arg, Val.get(), Loc, T.getOpenLocation(), KLoc, DelimLoc, RLoc);
1729 }
1730 
1731 static bool ParseReductionId(Parser &P, CXXScopeSpec &ReductionIdScopeSpec,
1732                              UnqualifiedId &ReductionId) {
1733   if (ReductionIdScopeSpec.isEmpty()) {
1734     auto OOK = OO_None;
1735     switch (P.getCurToken().getKind()) {
1736     case tok::plus:
1737       OOK = OO_Plus;
1738       break;
1739     case tok::minus:
1740       OOK = OO_Minus;
1741       break;
1742     case tok::star:
1743       OOK = OO_Star;
1744       break;
1745     case tok::amp:
1746       OOK = OO_Amp;
1747       break;
1748     case tok::pipe:
1749       OOK = OO_Pipe;
1750       break;
1751     case tok::caret:
1752       OOK = OO_Caret;
1753       break;
1754     case tok::ampamp:
1755       OOK = OO_AmpAmp;
1756       break;
1757     case tok::pipepipe:
1758       OOK = OO_PipePipe;
1759       break;
1760     default:
1761       break;
1762     }
1763     if (OOK != OO_None) {
1764       SourceLocation OpLoc = P.ConsumeToken();
1765       SourceLocation SymbolLocations[] = {OpLoc, OpLoc, SourceLocation()};
1766       ReductionId.setOperatorFunctionId(OpLoc, OOK, SymbolLocations);
1767       return false;
1768     }
1769   }
1770   return P.ParseUnqualifiedId(ReductionIdScopeSpec, /*EnteringContext*/ false,
1771                               /*AllowDestructorName*/ false,
1772                               /*AllowConstructorName*/ false,
1773                               /*AllowDeductionGuide*/ false,
1774                               nullptr, nullptr, ReductionId);
1775 }
1776 
1777 /// Parses clauses with list.
1778 bool Parser::ParseOpenMPVarList(OpenMPDirectiveKind DKind,
1779                                 OpenMPClauseKind Kind,
1780                                 SmallVectorImpl<Expr *> &Vars,
1781                                 OpenMPVarListDataTy &Data) {
1782   UnqualifiedId UnqualifiedReductionId;
1783   bool InvalidReductionId = false;
1784 
1785   // Parse '('.
1786   BalancedDelimiterTracker T(*this, tok::l_paren, tok::annot_pragma_openmp_end);
1787   if (T.expectAndConsume(diag::err_expected_lparen_after,
1788                          getOpenMPClauseName(Kind)))
1789     return true;
1790 
1791   bool NeedRParenForLinear = false;
1792   BalancedDelimiterTracker LinearT(*this, tok::l_paren,
1793                                   tok::annot_pragma_openmp_end);
1794   // Handle reduction-identifier for reduction clause.
1795   if (Kind == OMPC_reduction || Kind == OMPC_task_reduction ||
1796       Kind == OMPC_in_reduction) {
1797     ColonProtectionRAIIObject ColonRAII(*this);
1798     if (getLangOpts().CPlusPlus)
1799       ParseOptionalCXXScopeSpecifier(Data.ReductionIdScopeSpec,
1800                                      /*ObjectType=*/nullptr,
1801                                      /*EnteringContext=*/false);
1802     InvalidReductionId = ParseReductionId(*this, Data.ReductionIdScopeSpec,
1803                                           UnqualifiedReductionId);
1804     if (InvalidReductionId) {
1805       SkipUntil(tok::colon, tok::r_paren, tok::annot_pragma_openmp_end,
1806                 StopBeforeMatch);
1807     }
1808     if (Tok.is(tok::colon))
1809       Data.ColonLoc = ConsumeToken();
1810     else
1811       Diag(Tok, diag::warn_pragma_expected_colon) << "reduction identifier";
1812     if (!InvalidReductionId)
1813       Data.ReductionId =
1814           Actions.GetNameFromUnqualifiedId(UnqualifiedReductionId);
1815   } else if (Kind == OMPC_depend) {
1816   // Handle dependency type for depend clause.
1817     ColonProtectionRAIIObject ColonRAII(*this);
1818     Data.DepKind =
1819         static_cast<OpenMPDependClauseKind>(getOpenMPSimpleClauseType(
1820             Kind, Tok.is(tok::identifier) ? PP.getSpelling(Tok) : ""));
1821     Data.DepLinMapLoc = Tok.getLocation();
1822 
1823     if (Data.DepKind == OMPC_DEPEND_unknown) {
1824       SkipUntil(tok::colon, tok::r_paren, tok::annot_pragma_openmp_end,
1825                 StopBeforeMatch);
1826     } else {
1827       ConsumeToken();
1828       // Special processing for depend(source) clause.
1829       if (DKind == OMPD_ordered && Data.DepKind == OMPC_DEPEND_source) {
1830         // Parse ')'.
1831         T.consumeClose();
1832         return false;
1833       }
1834     }
1835     if (Tok.is(tok::colon)) {
1836       Data.ColonLoc = ConsumeToken();
1837     } else {
1838       Diag(Tok, DKind == OMPD_ordered ? diag::warn_pragma_expected_colon_r_paren
1839                                       : diag::warn_pragma_expected_colon)
1840           << "dependency type";
1841     }
1842   } else if (Kind == OMPC_linear) {
1843     // Try to parse modifier if any.
1844     if (Tok.is(tok::identifier) && PP.LookAhead(0).is(tok::l_paren)) {
1845       Data.LinKind = static_cast<OpenMPLinearClauseKind>(
1846           getOpenMPSimpleClauseType(Kind, PP.getSpelling(Tok)));
1847       Data.DepLinMapLoc = ConsumeToken();
1848       LinearT.consumeOpen();
1849       NeedRParenForLinear = true;
1850     }
1851   } else if (Kind == OMPC_map) {
1852     // Handle map type for map clause.
1853     ColonProtectionRAIIObject ColonRAII(*this);
1854 
1855     /// The map clause modifier token can be either a identifier or the C++
1856     /// delete keyword.
1857     auto &&IsMapClauseModifierToken = [](const Token &Tok) -> bool {
1858       return Tok.isOneOf(tok::identifier, tok::kw_delete);
1859     };
1860 
1861     // The first identifier may be a list item, a map-type or a
1862     // map-type-modifier. The map modifier can also be delete which has the same
1863     // spelling of the C++ delete keyword.
1864     Data.MapType =
1865         IsMapClauseModifierToken(Tok)
1866             ? static_cast<OpenMPMapClauseKind>(
1867                   getOpenMPSimpleClauseType(Kind, PP.getSpelling(Tok)))
1868             : OMPC_MAP_unknown;
1869     Data.DepLinMapLoc = Tok.getLocation();
1870 
1871     if (IsMapClauseModifierToken(Tok)) {
1872       if (PP.LookAhead(0).is(tok::colon)) {
1873         if (Data.MapType == OMPC_MAP_unknown)
1874           Diag(Tok, diag::err_omp_unknown_map_type);
1875         else if (Data.MapType == OMPC_MAP_always)
1876           Diag(Tok, diag::err_omp_map_type_missing);
1877         ConsumeToken();
1878       } else if (PP.LookAhead(0).is(tok::comma)) {
1879         if (IsMapClauseModifierToken(PP.LookAhead(1)) &&
1880             PP.LookAhead(2).is(tok::colon)) {
1881           Data.MapTypeModifier = Data.MapType;
1882           if (Data.MapTypeModifier != OMPC_MAP_always) {
1883             Diag(Tok, diag::err_omp_unknown_map_type_modifier);
1884             Data.MapTypeModifier = OMPC_MAP_unknown;
1885           }
1886 
1887           ConsumeToken();
1888           ConsumeToken();
1889 
1890           Data.MapType =
1891               IsMapClauseModifierToken(Tok)
1892                   ? static_cast<OpenMPMapClauseKind>(
1893                         getOpenMPSimpleClauseType(Kind, PP.getSpelling(Tok)))
1894                   : OMPC_MAP_unknown;
1895           if (Data.MapType == OMPC_MAP_unknown ||
1896               Data.MapType == OMPC_MAP_always)
1897             Diag(Tok, diag::err_omp_unknown_map_type);
1898           ConsumeToken();
1899         } else {
1900           Data.MapType = OMPC_MAP_tofrom;
1901           Data.IsMapTypeImplicit = true;
1902         }
1903       } else if (IsMapClauseModifierToken(PP.LookAhead(0))) {
1904         if (PP.LookAhead(1).is(tok::colon)) {
1905           Data.MapTypeModifier = Data.MapType;
1906           if (Data.MapTypeModifier != OMPC_MAP_always) {
1907             Diag(Tok, diag::err_omp_unknown_map_type_modifier);
1908             Data.MapTypeModifier = OMPC_MAP_unknown;
1909           }
1910 
1911           ConsumeToken();
1912 
1913           Data.MapType =
1914               IsMapClauseModifierToken(Tok)
1915                   ? static_cast<OpenMPMapClauseKind>(
1916                         getOpenMPSimpleClauseType(Kind, PP.getSpelling(Tok)))
1917                   : OMPC_MAP_unknown;
1918           if (Data.MapType == OMPC_MAP_unknown ||
1919               Data.MapType == OMPC_MAP_always)
1920             Diag(Tok, diag::err_omp_unknown_map_type);
1921           ConsumeToken();
1922         } else {
1923           Data.MapType = OMPC_MAP_tofrom;
1924           Data.IsMapTypeImplicit = true;
1925         }
1926       } else {
1927         Data.MapType = OMPC_MAP_tofrom;
1928         Data.IsMapTypeImplicit = true;
1929       }
1930     } else {
1931       Data.MapType = OMPC_MAP_tofrom;
1932       Data.IsMapTypeImplicit = true;
1933     }
1934 
1935     if (Tok.is(tok::colon))
1936       Data.ColonLoc = ConsumeToken();
1937   }
1938 
1939   bool IsComma =
1940       (Kind != OMPC_reduction && Kind != OMPC_task_reduction &&
1941        Kind != OMPC_in_reduction && Kind != OMPC_depend && Kind != OMPC_map) ||
1942       (Kind == OMPC_reduction && !InvalidReductionId) ||
1943       (Kind == OMPC_map && Data.MapType != OMPC_MAP_unknown) ||
1944       (Kind == OMPC_depend && Data.DepKind != OMPC_DEPEND_unknown);
1945   const bool MayHaveTail = (Kind == OMPC_linear || Kind == OMPC_aligned);
1946   while (IsComma || (Tok.isNot(tok::r_paren) && Tok.isNot(tok::colon) &&
1947                      Tok.isNot(tok::annot_pragma_openmp_end))) {
1948     ColonProtectionRAIIObject ColonRAII(*this, MayHaveTail);
1949     // Parse variable
1950     ExprResult VarExpr =
1951         Actions.CorrectDelayedTyposInExpr(ParseAssignmentExpression());
1952     if (VarExpr.isUsable()) {
1953       Vars.push_back(VarExpr.get());
1954     } else {
1955       SkipUntil(tok::comma, tok::r_paren, tok::annot_pragma_openmp_end,
1956                 StopBeforeMatch);
1957     }
1958     // Skip ',' if any
1959     IsComma = Tok.is(tok::comma);
1960     if (IsComma)
1961       ConsumeToken();
1962     else if (Tok.isNot(tok::r_paren) &&
1963              Tok.isNot(tok::annot_pragma_openmp_end) &&
1964              (!MayHaveTail || Tok.isNot(tok::colon)))
1965       Diag(Tok, diag::err_omp_expected_punc)
1966           << ((Kind == OMPC_flush) ? getOpenMPDirectiveName(OMPD_flush)
1967                                    : getOpenMPClauseName(Kind))
1968           << (Kind == OMPC_flush);
1969   }
1970 
1971   // Parse ')' for linear clause with modifier.
1972   if (NeedRParenForLinear)
1973     LinearT.consumeClose();
1974 
1975   // Parse ':' linear-step (or ':' alignment).
1976   const bool MustHaveTail = MayHaveTail && Tok.is(tok::colon);
1977   if (MustHaveTail) {
1978     Data.ColonLoc = Tok.getLocation();
1979     SourceLocation ELoc = ConsumeToken();
1980     ExprResult Tail = ParseAssignmentExpression();
1981     Tail = Actions.ActOnFinishFullExpr(Tail.get(), ELoc);
1982     if (Tail.isUsable())
1983       Data.TailExpr = Tail.get();
1984     else
1985       SkipUntil(tok::comma, tok::r_paren, tok::annot_pragma_openmp_end,
1986                 StopBeforeMatch);
1987   }
1988 
1989   // Parse ')'.
1990   Data.RLoc = Tok.getLocation();
1991   if (!T.consumeClose())
1992     Data.RLoc = T.getCloseLocation();
1993   return (Kind == OMPC_depend && Data.DepKind != OMPC_DEPEND_unknown &&
1994           Vars.empty()) ||
1995          (Kind != OMPC_depend && Kind != OMPC_map && Vars.empty()) ||
1996          (MustHaveTail && !Data.TailExpr) || InvalidReductionId;
1997 }
1998 
1999 /// Parsing of OpenMP clause 'private', 'firstprivate', 'lastprivate',
2000 /// 'shared', 'copyin', 'copyprivate', 'flush', 'reduction', 'task_reduction' or
2001 /// 'in_reduction'.
2002 ///
2003 ///    private-clause:
2004 ///       'private' '(' list ')'
2005 ///    firstprivate-clause:
2006 ///       'firstprivate' '(' list ')'
2007 ///    lastprivate-clause:
2008 ///       'lastprivate' '(' list ')'
2009 ///    shared-clause:
2010 ///       'shared' '(' list ')'
2011 ///    linear-clause:
2012 ///       'linear' '(' linear-list [ ':' linear-step ] ')'
2013 ///    aligned-clause:
2014 ///       'aligned' '(' list [ ':' alignment ] ')'
2015 ///    reduction-clause:
2016 ///       'reduction' '(' reduction-identifier ':' list ')'
2017 ///    task_reduction-clause:
2018 ///       'task_reduction' '(' reduction-identifier ':' list ')'
2019 ///    in_reduction-clause:
2020 ///       'in_reduction' '(' reduction-identifier ':' list ')'
2021 ///    copyprivate-clause:
2022 ///       'copyprivate' '(' list ')'
2023 ///    flush-clause:
2024 ///       'flush' '(' list ')'
2025 ///    depend-clause:
2026 ///       'depend' '(' in | out | inout : list | source ')'
2027 ///    map-clause:
2028 ///       'map' '(' [ [ always , ]
2029 ///          to | from | tofrom | alloc | release | delete ':' ] list ')';
2030 ///    to-clause:
2031 ///       'to' '(' list ')'
2032 ///    from-clause:
2033 ///       'from' '(' list ')'
2034 ///    use_device_ptr-clause:
2035 ///       'use_device_ptr' '(' list ')'
2036 ///    is_device_ptr-clause:
2037 ///       'is_device_ptr' '(' list ')'
2038 ///
2039 /// For 'linear' clause linear-list may have the following forms:
2040 ///  list
2041 ///  modifier(list)
2042 /// where modifier is 'val' (C) or 'ref', 'val' or 'uval'(C++).
2043 OMPClause *Parser::ParseOpenMPVarListClause(OpenMPDirectiveKind DKind,
2044                                             OpenMPClauseKind Kind,
2045                                             bool ParseOnly) {
2046   SourceLocation Loc = Tok.getLocation();
2047   SourceLocation LOpen = ConsumeToken();
2048   SmallVector<Expr *, 4> Vars;
2049   OpenMPVarListDataTy Data;
2050 
2051   if (ParseOpenMPVarList(DKind, Kind, Vars, Data))
2052     return nullptr;
2053 
2054   if (ParseOnly)
2055     return nullptr;
2056   return Actions.ActOnOpenMPVarListClause(
2057       Kind, Vars, Data.TailExpr, Loc, LOpen, Data.ColonLoc, Data.RLoc,
2058       Data.ReductionIdScopeSpec, Data.ReductionId, Data.DepKind, Data.LinKind,
2059       Data.MapTypeModifier, Data.MapType, Data.IsMapTypeImplicit,
2060       Data.DepLinMapLoc);
2061 }
2062 
2063