1 //===--- ParseOpenMP.cpp - OpenMP directives parsing ----------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 /// \file
9 /// This file implements parsing of all OpenMP directives and clauses.
10 ///
11 //===----------------------------------------------------------------------===//
12 
13 #include "clang/AST/ASTContext.h"
14 #include "clang/AST/StmtOpenMP.h"
15 #include "clang/Parse/ParseDiagnostic.h"
16 #include "clang/Parse/Parser.h"
17 #include "clang/Parse/RAIIObjectsForParser.h"
18 #include "clang/Sema/Scope.h"
19 #include "llvm/ADT/PointerIntPair.h"
20 #include "llvm/ADT/UniqueVector.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   OMPD_mapper,
46   OMPD_variant,
47   OMPD_parallel_master,
48 };
49 
50 class DeclDirectiveListParserHelper final {
51   SmallVector<Expr *, 4> Identifiers;
52   Parser *P;
53   OpenMPDirectiveKind Kind;
54 
55 public:
56   DeclDirectiveListParserHelper(Parser *P, OpenMPDirectiveKind Kind)
57       : P(P), Kind(Kind) {}
58   void operator()(CXXScopeSpec &SS, DeclarationNameInfo NameInfo) {
59     ExprResult Res = P->getActions().ActOnOpenMPIdExpression(
60         P->getCurScope(), SS, NameInfo, Kind);
61     if (Res.isUsable())
62       Identifiers.push_back(Res.get());
63   }
64   llvm::ArrayRef<Expr *> getIdentifiers() const { return Identifiers; }
65 };
66 } // namespace
67 
68 // Map token string to extended OMP token kind that are
69 // OpenMPDirectiveKind + OpenMPDirectiveKindEx.
70 static unsigned getOpenMPDirectiveKindEx(StringRef S) {
71   auto DKind = getOpenMPDirectiveKind(S);
72   if (DKind != OMPD_unknown)
73     return DKind;
74 
75   return llvm::StringSwitch<unsigned>(S)
76       .Case("cancellation", OMPD_cancellation)
77       .Case("data", OMPD_data)
78       .Case("declare", OMPD_declare)
79       .Case("end", OMPD_end)
80       .Case("enter", OMPD_enter)
81       .Case("exit", OMPD_exit)
82       .Case("point", OMPD_point)
83       .Case("reduction", OMPD_reduction)
84       .Case("update", OMPD_update)
85       .Case("mapper", OMPD_mapper)
86       .Case("variant", OMPD_variant)
87       .Default(OMPD_unknown);
88 }
89 
90 static OpenMPDirectiveKind parseOpenMPDirectiveKind(Parser &P) {
91   // Array of foldings: F[i][0] F[i][1] ===> F[i][2].
92   // E.g.: OMPD_for OMPD_simd ===> OMPD_for_simd
93   // TODO: add other combined directives in topological order.
94   static const unsigned F[][3] = {
95       {OMPD_cancellation, OMPD_point, OMPD_cancellation_point},
96       {OMPD_declare, OMPD_reduction, OMPD_declare_reduction},
97       {OMPD_declare, OMPD_mapper, OMPD_declare_mapper},
98       {OMPD_declare, OMPD_simd, OMPD_declare_simd},
99       {OMPD_declare, OMPD_target, OMPD_declare_target},
100       {OMPD_declare, OMPD_variant, OMPD_declare_variant},
101       {OMPD_distribute, OMPD_parallel, OMPD_distribute_parallel},
102       {OMPD_distribute_parallel, OMPD_for, OMPD_distribute_parallel_for},
103       {OMPD_distribute_parallel_for, OMPD_simd,
104        OMPD_distribute_parallel_for_simd},
105       {OMPD_distribute, OMPD_simd, OMPD_distribute_simd},
106       {OMPD_end, OMPD_declare, OMPD_end_declare},
107       {OMPD_end_declare, OMPD_target, OMPD_end_declare_target},
108       {OMPD_target, OMPD_data, OMPD_target_data},
109       {OMPD_target, OMPD_enter, OMPD_target_enter},
110       {OMPD_target, OMPD_exit, OMPD_target_exit},
111       {OMPD_target, OMPD_update, OMPD_target_update},
112       {OMPD_target_enter, OMPD_data, OMPD_target_enter_data},
113       {OMPD_target_exit, OMPD_data, OMPD_target_exit_data},
114       {OMPD_for, OMPD_simd, OMPD_for_simd},
115       {OMPD_parallel, OMPD_for, OMPD_parallel_for},
116       {OMPD_parallel_for, OMPD_simd, OMPD_parallel_for_simd},
117       {OMPD_parallel, OMPD_sections, OMPD_parallel_sections},
118       {OMPD_taskloop, OMPD_simd, OMPD_taskloop_simd},
119       {OMPD_target, OMPD_parallel, OMPD_target_parallel},
120       {OMPD_target, OMPD_simd, OMPD_target_simd},
121       {OMPD_target_parallel, OMPD_for, OMPD_target_parallel_for},
122       {OMPD_target_parallel_for, OMPD_simd, OMPD_target_parallel_for_simd},
123       {OMPD_teams, OMPD_distribute, OMPD_teams_distribute},
124       {OMPD_teams_distribute, OMPD_simd, OMPD_teams_distribute_simd},
125       {OMPD_teams_distribute, OMPD_parallel, OMPD_teams_distribute_parallel},
126       {OMPD_teams_distribute_parallel, OMPD_for,
127        OMPD_teams_distribute_parallel_for},
128       {OMPD_teams_distribute_parallel_for, OMPD_simd,
129        OMPD_teams_distribute_parallel_for_simd},
130       {OMPD_target, OMPD_teams, OMPD_target_teams},
131       {OMPD_target_teams, OMPD_distribute, OMPD_target_teams_distribute},
132       {OMPD_target_teams_distribute, OMPD_parallel,
133        OMPD_target_teams_distribute_parallel},
134       {OMPD_target_teams_distribute, OMPD_simd,
135        OMPD_target_teams_distribute_simd},
136       {OMPD_target_teams_distribute_parallel, OMPD_for,
137        OMPD_target_teams_distribute_parallel_for},
138       {OMPD_target_teams_distribute_parallel_for, OMPD_simd,
139        OMPD_target_teams_distribute_parallel_for_simd},
140       {OMPD_master, OMPD_taskloop, OMPD_master_taskloop},
141       {OMPD_master_taskloop, OMPD_simd, OMPD_master_taskloop_simd},
142       {OMPD_parallel, OMPD_master, OMPD_parallel_master},
143       {OMPD_parallel_master, OMPD_taskloop, OMPD_parallel_master_taskloop},
144       {OMPD_parallel_master_taskloop, OMPD_simd,
145        OMPD_parallel_master_taskloop_simd}};
146   enum { CancellationPoint = 0, DeclareReduction = 1, TargetData = 2 };
147   Token Tok = P.getCurToken();
148   unsigned DKind =
149       Tok.isAnnotation()
150           ? static_cast<unsigned>(OMPD_unknown)
151           : getOpenMPDirectiveKindEx(P.getPreprocessor().getSpelling(Tok));
152   if (DKind == OMPD_unknown)
153     return OMPD_unknown;
154 
155   for (unsigned I = 0; I < llvm::array_lengthof(F); ++I) {
156     if (DKind != F[I][0])
157       continue;
158 
159     Tok = P.getPreprocessor().LookAhead(0);
160     unsigned SDKind =
161         Tok.isAnnotation()
162             ? static_cast<unsigned>(OMPD_unknown)
163             : getOpenMPDirectiveKindEx(P.getPreprocessor().getSpelling(Tok));
164     if (SDKind == OMPD_unknown)
165       continue;
166 
167     if (SDKind == F[I][1]) {
168       P.ConsumeToken();
169       DKind = F[I][2];
170     }
171   }
172   return DKind < OMPD_unknown ? static_cast<OpenMPDirectiveKind>(DKind)
173                               : OMPD_unknown;
174 }
175 
176 static DeclarationName parseOpenMPReductionId(Parser &P) {
177   Token Tok = P.getCurToken();
178   Sema &Actions = P.getActions();
179   OverloadedOperatorKind OOK = OO_None;
180   // Allow to use 'operator' keyword for C++ operators
181   bool WithOperator = false;
182   if (Tok.is(tok::kw_operator)) {
183     P.ConsumeToken();
184     Tok = P.getCurToken();
185     WithOperator = true;
186   }
187   switch (Tok.getKind()) {
188   case tok::plus: // '+'
189     OOK = OO_Plus;
190     break;
191   case tok::minus: // '-'
192     OOK = OO_Minus;
193     break;
194   case tok::star: // '*'
195     OOK = OO_Star;
196     break;
197   case tok::amp: // '&'
198     OOK = OO_Amp;
199     break;
200   case tok::pipe: // '|'
201     OOK = OO_Pipe;
202     break;
203   case tok::caret: // '^'
204     OOK = OO_Caret;
205     break;
206   case tok::ampamp: // '&&'
207     OOK = OO_AmpAmp;
208     break;
209   case tok::pipepipe: // '||'
210     OOK = OO_PipePipe;
211     break;
212   case tok::identifier: // identifier
213     if (!WithOperator)
214       break;
215     LLVM_FALLTHROUGH;
216   default:
217     P.Diag(Tok.getLocation(), diag::err_omp_expected_reduction_identifier);
218     P.SkipUntil(tok::colon, tok::r_paren, tok::annot_pragma_openmp_end,
219                 Parser::StopBeforeMatch);
220     return DeclarationName();
221   }
222   P.ConsumeToken();
223   auto &DeclNames = Actions.getASTContext().DeclarationNames;
224   return OOK == OO_None ? DeclNames.getIdentifier(Tok.getIdentifierInfo())
225                         : DeclNames.getCXXOperatorName(OOK);
226 }
227 
228 /// Parse 'omp declare reduction' construct.
229 ///
230 ///       declare-reduction-directive:
231 ///        annot_pragma_openmp 'declare' 'reduction'
232 ///        '(' <reduction_id> ':' <type> {',' <type>} ':' <expression> ')'
233 ///        ['initializer' '(' ('omp_priv' '=' <expression>)|<function_call> ')']
234 ///        annot_pragma_openmp_end
235 /// <reduction_id> is either a base language identifier or one of the following
236 /// operators: '+', '-', '*', '&', '|', '^', '&&' and '||'.
237 ///
238 Parser::DeclGroupPtrTy
239 Parser::ParseOpenMPDeclareReductionDirective(AccessSpecifier AS) {
240   // Parse '('.
241   BalancedDelimiterTracker T(*this, tok::l_paren, tok::annot_pragma_openmp_end);
242   if (T.expectAndConsume(diag::err_expected_lparen_after,
243                          getOpenMPDirectiveName(OMPD_declare_reduction))) {
244     SkipUntil(tok::annot_pragma_openmp_end, StopBeforeMatch);
245     return DeclGroupPtrTy();
246   }
247 
248   DeclarationName Name = parseOpenMPReductionId(*this);
249   if (Name.isEmpty() && Tok.is(tok::annot_pragma_openmp_end))
250     return DeclGroupPtrTy();
251 
252   // Consume ':'.
253   bool IsCorrect = !ExpectAndConsume(tok::colon);
254 
255   if (!IsCorrect && Tok.is(tok::annot_pragma_openmp_end))
256     return DeclGroupPtrTy();
257 
258   IsCorrect = IsCorrect && !Name.isEmpty();
259 
260   if (Tok.is(tok::colon) || Tok.is(tok::annot_pragma_openmp_end)) {
261     Diag(Tok.getLocation(), diag::err_expected_type);
262     IsCorrect = false;
263   }
264 
265   if (!IsCorrect && Tok.is(tok::annot_pragma_openmp_end))
266     return DeclGroupPtrTy();
267 
268   SmallVector<std::pair<QualType, SourceLocation>, 8> ReductionTypes;
269   // Parse list of types until ':' token.
270   do {
271     ColonProtectionRAIIObject ColonRAII(*this);
272     SourceRange Range;
273     TypeResult TR =
274         ParseTypeName(&Range, DeclaratorContext::PrototypeContext, AS);
275     if (TR.isUsable()) {
276       QualType ReductionType =
277           Actions.ActOnOpenMPDeclareReductionType(Range.getBegin(), TR);
278       if (!ReductionType.isNull()) {
279         ReductionTypes.push_back(
280             std::make_pair(ReductionType, Range.getBegin()));
281       }
282     } else {
283       SkipUntil(tok::comma, tok::colon, tok::annot_pragma_openmp_end,
284                 StopBeforeMatch);
285     }
286 
287     if (Tok.is(tok::colon) || Tok.is(tok::annot_pragma_openmp_end))
288       break;
289 
290     // Consume ','.
291     if (ExpectAndConsume(tok::comma)) {
292       IsCorrect = false;
293       if (Tok.is(tok::annot_pragma_openmp_end)) {
294         Diag(Tok.getLocation(), diag::err_expected_type);
295         return DeclGroupPtrTy();
296       }
297     }
298   } while (Tok.isNot(tok::annot_pragma_openmp_end));
299 
300   if (ReductionTypes.empty()) {
301     SkipUntil(tok::annot_pragma_openmp_end, StopBeforeMatch);
302     return DeclGroupPtrTy();
303   }
304 
305   if (!IsCorrect && Tok.is(tok::annot_pragma_openmp_end))
306     return DeclGroupPtrTy();
307 
308   // Consume ':'.
309   if (ExpectAndConsume(tok::colon))
310     IsCorrect = false;
311 
312   if (Tok.is(tok::annot_pragma_openmp_end)) {
313     Diag(Tok.getLocation(), diag::err_expected_expression);
314     return DeclGroupPtrTy();
315   }
316 
317   DeclGroupPtrTy DRD = Actions.ActOnOpenMPDeclareReductionDirectiveStart(
318       getCurScope(), Actions.getCurLexicalContext(), Name, ReductionTypes, AS);
319 
320   // Parse <combiner> expression and then parse initializer if any for each
321   // correct type.
322   unsigned I = 0, E = ReductionTypes.size();
323   for (Decl *D : DRD.get()) {
324     TentativeParsingAction TPA(*this);
325     ParseScope OMPDRScope(this, Scope::FnScope | Scope::DeclScope |
326                                     Scope::CompoundStmtScope |
327                                     Scope::OpenMPDirectiveScope);
328     // Parse <combiner> expression.
329     Actions.ActOnOpenMPDeclareReductionCombinerStart(getCurScope(), D);
330     ExprResult CombinerResult =
331         Actions.ActOnFinishFullExpr(ParseAssignmentExpression().get(),
332                                     D->getLocation(), /*DiscardedValue*/ false);
333     Actions.ActOnOpenMPDeclareReductionCombinerEnd(D, CombinerResult.get());
334 
335     if (CombinerResult.isInvalid() && Tok.isNot(tok::r_paren) &&
336         Tok.isNot(tok::annot_pragma_openmp_end)) {
337       TPA.Commit();
338       IsCorrect = false;
339       break;
340     }
341     IsCorrect = !T.consumeClose() && IsCorrect && CombinerResult.isUsable();
342     ExprResult InitializerResult;
343     if (Tok.isNot(tok::annot_pragma_openmp_end)) {
344       // Parse <initializer> expression.
345       if (Tok.is(tok::identifier) &&
346           Tok.getIdentifierInfo()->isStr("initializer")) {
347         ConsumeToken();
348       } else {
349         Diag(Tok.getLocation(), diag::err_expected) << "'initializer'";
350         TPA.Commit();
351         IsCorrect = false;
352         break;
353       }
354       // Parse '('.
355       BalancedDelimiterTracker T(*this, tok::l_paren,
356                                  tok::annot_pragma_openmp_end);
357       IsCorrect =
358           !T.expectAndConsume(diag::err_expected_lparen_after, "initializer") &&
359           IsCorrect;
360       if (Tok.isNot(tok::annot_pragma_openmp_end)) {
361         ParseScope OMPDRScope(this, Scope::FnScope | Scope::DeclScope |
362                                         Scope::CompoundStmtScope |
363                                         Scope::OpenMPDirectiveScope);
364         // Parse expression.
365         VarDecl *OmpPrivParm =
366             Actions.ActOnOpenMPDeclareReductionInitializerStart(getCurScope(),
367                                                                 D);
368         // Check if initializer is omp_priv <init_expr> or something else.
369         if (Tok.is(tok::identifier) &&
370             Tok.getIdentifierInfo()->isStr("omp_priv")) {
371           if (Actions.getLangOpts().CPlusPlus) {
372             InitializerResult = Actions.ActOnFinishFullExpr(
373                 ParseAssignmentExpression().get(), D->getLocation(),
374                 /*DiscardedValue*/ false);
375           } else {
376             ConsumeToken();
377             ParseOpenMPReductionInitializerForDecl(OmpPrivParm);
378           }
379         } else {
380           InitializerResult = Actions.ActOnFinishFullExpr(
381               ParseAssignmentExpression().get(), D->getLocation(),
382               /*DiscardedValue*/ false);
383         }
384         Actions.ActOnOpenMPDeclareReductionInitializerEnd(
385             D, InitializerResult.get(), OmpPrivParm);
386         if (InitializerResult.isInvalid() && Tok.isNot(tok::r_paren) &&
387             Tok.isNot(tok::annot_pragma_openmp_end)) {
388           TPA.Commit();
389           IsCorrect = false;
390           break;
391         }
392         IsCorrect =
393             !T.consumeClose() && IsCorrect && !InitializerResult.isInvalid();
394       }
395     }
396 
397     ++I;
398     // Revert parsing if not the last type, otherwise accept it, we're done with
399     // parsing.
400     if (I != E)
401       TPA.Revert();
402     else
403       TPA.Commit();
404   }
405   return Actions.ActOnOpenMPDeclareReductionDirectiveEnd(getCurScope(), DRD,
406                                                          IsCorrect);
407 }
408 
409 void Parser::ParseOpenMPReductionInitializerForDecl(VarDecl *OmpPrivParm) {
410   // Parse declarator '=' initializer.
411   // If a '==' or '+=' is found, suggest a fixit to '='.
412   if (isTokenEqualOrEqualTypo()) {
413     ConsumeToken();
414 
415     if (Tok.is(tok::code_completion)) {
416       Actions.CodeCompleteInitializer(getCurScope(), OmpPrivParm);
417       Actions.FinalizeDeclaration(OmpPrivParm);
418       cutOffParsing();
419       return;
420     }
421 
422     ExprResult Init(ParseInitializer());
423 
424     if (Init.isInvalid()) {
425       SkipUntil(tok::r_paren, tok::annot_pragma_openmp_end, StopBeforeMatch);
426       Actions.ActOnInitializerError(OmpPrivParm);
427     } else {
428       Actions.AddInitializerToDecl(OmpPrivParm, Init.get(),
429                                    /*DirectInit=*/false);
430     }
431   } else if (Tok.is(tok::l_paren)) {
432     // Parse C++ direct initializer: '(' expression-list ')'
433     BalancedDelimiterTracker T(*this, tok::l_paren);
434     T.consumeOpen();
435 
436     ExprVector Exprs;
437     CommaLocsTy CommaLocs;
438 
439     SourceLocation LParLoc = T.getOpenLocation();
440     auto RunSignatureHelp = [this, OmpPrivParm, LParLoc, &Exprs]() {
441       QualType PreferredType = Actions.ProduceConstructorSignatureHelp(
442           getCurScope(), OmpPrivParm->getType()->getCanonicalTypeInternal(),
443           OmpPrivParm->getLocation(), Exprs, LParLoc);
444       CalledSignatureHelp = true;
445       return PreferredType;
446     };
447     if (ParseExpressionList(Exprs, CommaLocs, [&] {
448           PreferredType.enterFunctionArgument(Tok.getLocation(),
449                                               RunSignatureHelp);
450         })) {
451       if (PP.isCodeCompletionReached() && !CalledSignatureHelp)
452         RunSignatureHelp();
453       Actions.ActOnInitializerError(OmpPrivParm);
454       SkipUntil(tok::r_paren, tok::annot_pragma_openmp_end, StopBeforeMatch);
455     } else {
456       // Match the ')'.
457       SourceLocation RLoc = Tok.getLocation();
458       if (!T.consumeClose())
459         RLoc = T.getCloseLocation();
460 
461       assert(!Exprs.empty() && Exprs.size() - 1 == CommaLocs.size() &&
462              "Unexpected number of commas!");
463 
464       ExprResult Initializer =
465           Actions.ActOnParenListExpr(T.getOpenLocation(), RLoc, Exprs);
466       Actions.AddInitializerToDecl(OmpPrivParm, Initializer.get(),
467                                    /*DirectInit=*/true);
468     }
469   } else if (getLangOpts().CPlusPlus11 && Tok.is(tok::l_brace)) {
470     // Parse C++0x braced-init-list.
471     Diag(Tok, diag::warn_cxx98_compat_generalized_initializer_lists);
472 
473     ExprResult Init(ParseBraceInitializer());
474 
475     if (Init.isInvalid()) {
476       Actions.ActOnInitializerError(OmpPrivParm);
477     } else {
478       Actions.AddInitializerToDecl(OmpPrivParm, Init.get(),
479                                    /*DirectInit=*/true);
480     }
481   } else {
482     Actions.ActOnUninitializedDecl(OmpPrivParm);
483   }
484 }
485 
486 /// Parses 'omp declare mapper' directive.
487 ///
488 ///       declare-mapper-directive:
489 ///         annot_pragma_openmp 'declare' 'mapper' '(' [<mapper-identifier> ':']
490 ///         <type> <var> ')' [<clause>[[,] <clause>] ... ]
491 ///         annot_pragma_openmp_end
492 /// <mapper-identifier> and <var> are base language identifiers.
493 ///
494 Parser::DeclGroupPtrTy
495 Parser::ParseOpenMPDeclareMapperDirective(AccessSpecifier AS) {
496   bool IsCorrect = true;
497   // Parse '('
498   BalancedDelimiterTracker T(*this, tok::l_paren, tok::annot_pragma_openmp_end);
499   if (T.expectAndConsume(diag::err_expected_lparen_after,
500                          getOpenMPDirectiveName(OMPD_declare_mapper))) {
501     SkipUntil(tok::annot_pragma_openmp_end, StopBeforeMatch);
502     return DeclGroupPtrTy();
503   }
504 
505   // Parse <mapper-identifier>
506   auto &DeclNames = Actions.getASTContext().DeclarationNames;
507   DeclarationName MapperId;
508   if (PP.LookAhead(0).is(tok::colon)) {
509     if (Tok.isNot(tok::identifier) && Tok.isNot(tok::kw_default)) {
510       Diag(Tok.getLocation(), diag::err_omp_mapper_illegal_identifier);
511       IsCorrect = false;
512     } else {
513       MapperId = DeclNames.getIdentifier(Tok.getIdentifierInfo());
514     }
515     ConsumeToken();
516     // Consume ':'.
517     ExpectAndConsume(tok::colon);
518   } else {
519     // If no mapper identifier is provided, its name is "default" by default
520     MapperId =
521         DeclNames.getIdentifier(&Actions.getASTContext().Idents.get("default"));
522   }
523 
524   if (!IsCorrect && Tok.is(tok::annot_pragma_openmp_end))
525     return DeclGroupPtrTy();
526 
527   // Parse <type> <var>
528   DeclarationName VName;
529   QualType MapperType;
530   SourceRange Range;
531   TypeResult ParsedType = parseOpenMPDeclareMapperVarDecl(Range, VName, AS);
532   if (ParsedType.isUsable())
533     MapperType =
534         Actions.ActOnOpenMPDeclareMapperType(Range.getBegin(), ParsedType);
535   if (MapperType.isNull())
536     IsCorrect = false;
537   if (!IsCorrect) {
538     SkipUntil(tok::annot_pragma_openmp_end, Parser::StopBeforeMatch);
539     return DeclGroupPtrTy();
540   }
541 
542   // Consume ')'.
543   IsCorrect &= !T.consumeClose();
544   if (!IsCorrect) {
545     SkipUntil(tok::annot_pragma_openmp_end, Parser::StopBeforeMatch);
546     return DeclGroupPtrTy();
547   }
548 
549   // Enter scope.
550   OMPDeclareMapperDecl *DMD = Actions.ActOnOpenMPDeclareMapperDirectiveStart(
551       getCurScope(), Actions.getCurLexicalContext(), MapperId, MapperType,
552       Range.getBegin(), VName, AS);
553   DeclarationNameInfo DirName;
554   SourceLocation Loc = Tok.getLocation();
555   unsigned ScopeFlags = Scope::FnScope | Scope::DeclScope |
556                         Scope::CompoundStmtScope | Scope::OpenMPDirectiveScope;
557   ParseScope OMPDirectiveScope(this, ScopeFlags);
558   Actions.StartOpenMPDSABlock(OMPD_declare_mapper, DirName, getCurScope(), Loc);
559 
560   // Add the mapper variable declaration.
561   Actions.ActOnOpenMPDeclareMapperDirectiveVarDecl(
562       DMD, getCurScope(), MapperType, Range.getBegin(), VName);
563 
564   // Parse map clauses.
565   SmallVector<OMPClause *, 6> Clauses;
566   while (Tok.isNot(tok::annot_pragma_openmp_end)) {
567     OpenMPClauseKind CKind = Tok.isAnnotation()
568                                  ? OMPC_unknown
569                                  : getOpenMPClauseKind(PP.getSpelling(Tok));
570     Actions.StartOpenMPClause(CKind);
571     OMPClause *Clause =
572         ParseOpenMPClause(OMPD_declare_mapper, CKind, Clauses.size() == 0);
573     if (Clause)
574       Clauses.push_back(Clause);
575     else
576       IsCorrect = false;
577     // Skip ',' if any.
578     if (Tok.is(tok::comma))
579       ConsumeToken();
580     Actions.EndOpenMPClause();
581   }
582   if (Clauses.empty()) {
583     Diag(Tok, diag::err_omp_expected_clause)
584         << getOpenMPDirectiveName(OMPD_declare_mapper);
585     IsCorrect = false;
586   }
587 
588   // Exit scope.
589   Actions.EndOpenMPDSABlock(nullptr);
590   OMPDirectiveScope.Exit();
591 
592   DeclGroupPtrTy DGP =
593       Actions.ActOnOpenMPDeclareMapperDirectiveEnd(DMD, getCurScope(), Clauses);
594   if (!IsCorrect)
595     return DeclGroupPtrTy();
596   return DGP;
597 }
598 
599 TypeResult Parser::parseOpenMPDeclareMapperVarDecl(SourceRange &Range,
600                                                    DeclarationName &Name,
601                                                    AccessSpecifier AS) {
602   // Parse the common declaration-specifiers piece.
603   Parser::DeclSpecContext DSC = Parser::DeclSpecContext::DSC_type_specifier;
604   DeclSpec DS(AttrFactory);
605   ParseSpecifierQualifierList(DS, AS, DSC);
606 
607   // Parse the declarator.
608   DeclaratorContext Context = DeclaratorContext::PrototypeContext;
609   Declarator DeclaratorInfo(DS, Context);
610   ParseDeclarator(DeclaratorInfo);
611   Range = DeclaratorInfo.getSourceRange();
612   if (DeclaratorInfo.getIdentifier() == nullptr) {
613     Diag(Tok.getLocation(), diag::err_omp_mapper_expected_declarator);
614     return true;
615   }
616   Name = Actions.GetNameForDeclarator(DeclaratorInfo).getName();
617 
618   return Actions.ActOnOpenMPDeclareMapperVarDecl(getCurScope(), DeclaratorInfo);
619 }
620 
621 namespace {
622 /// RAII that recreates function context for correct parsing of clauses of
623 /// 'declare simd' construct.
624 /// OpenMP, 2.8.2 declare simd Construct
625 /// The expressions appearing in the clauses of this directive are evaluated in
626 /// the scope of the arguments of the function declaration or definition.
627 class FNContextRAII final {
628   Parser &P;
629   Sema::CXXThisScopeRAII *ThisScope;
630   Parser::ParseScope *TempScope;
631   Parser::ParseScope *FnScope;
632   bool HasTemplateScope = false;
633   bool HasFunScope = false;
634   FNContextRAII() = delete;
635   FNContextRAII(const FNContextRAII &) = delete;
636   FNContextRAII &operator=(const FNContextRAII &) = delete;
637 
638 public:
639   FNContextRAII(Parser &P, Parser::DeclGroupPtrTy Ptr) : P(P) {
640     Decl *D = *Ptr.get().begin();
641     NamedDecl *ND = dyn_cast<NamedDecl>(D);
642     RecordDecl *RD = dyn_cast_or_null<RecordDecl>(D->getDeclContext());
643     Sema &Actions = P.getActions();
644 
645     // Allow 'this' within late-parsed attributes.
646     ThisScope = new Sema::CXXThisScopeRAII(Actions, RD, Qualifiers(),
647                                            ND && ND->isCXXInstanceMember());
648 
649     // If the Decl is templatized, add template parameters to scope.
650     HasTemplateScope = D->isTemplateDecl();
651     TempScope =
652         new Parser::ParseScope(&P, Scope::TemplateParamScope, HasTemplateScope);
653     if (HasTemplateScope)
654       Actions.ActOnReenterTemplateScope(Actions.getCurScope(), D);
655 
656     // If the Decl is on a function, add function parameters to the scope.
657     HasFunScope = D->isFunctionOrFunctionTemplate();
658     FnScope = new Parser::ParseScope(
659         &P, Scope::FnScope | Scope::DeclScope | Scope::CompoundStmtScope,
660         HasFunScope);
661     if (HasFunScope)
662       Actions.ActOnReenterFunctionContext(Actions.getCurScope(), D);
663   }
664   ~FNContextRAII() {
665     if (HasFunScope) {
666       P.getActions().ActOnExitFunctionContext();
667       FnScope->Exit(); // Pop scope, and remove Decls from IdResolver
668     }
669     if (HasTemplateScope)
670       TempScope->Exit();
671     delete FnScope;
672     delete TempScope;
673     delete ThisScope;
674   }
675 };
676 } // namespace
677 
678 /// Parses clauses for 'declare simd' directive.
679 ///    clause:
680 ///      'inbranch' | 'notinbranch'
681 ///      'simdlen' '(' <expr> ')'
682 ///      { 'uniform' '(' <argument_list> ')' }
683 ///      { 'aligned '(' <argument_list> [ ':' <alignment> ] ')' }
684 ///      { 'linear '(' <argument_list> [ ':' <step> ] ')' }
685 static bool parseDeclareSimdClauses(
686     Parser &P, OMPDeclareSimdDeclAttr::BranchStateTy &BS, ExprResult &SimdLen,
687     SmallVectorImpl<Expr *> &Uniforms, SmallVectorImpl<Expr *> &Aligneds,
688     SmallVectorImpl<Expr *> &Alignments, SmallVectorImpl<Expr *> &Linears,
689     SmallVectorImpl<unsigned> &LinModifiers, SmallVectorImpl<Expr *> &Steps) {
690   SourceRange BSRange;
691   const Token &Tok = P.getCurToken();
692   bool IsError = false;
693   while (Tok.isNot(tok::annot_pragma_openmp_end)) {
694     if (Tok.isNot(tok::identifier))
695       break;
696     OMPDeclareSimdDeclAttr::BranchStateTy Out;
697     IdentifierInfo *II = Tok.getIdentifierInfo();
698     StringRef ClauseName = II->getName();
699     // Parse 'inranch|notinbranch' clauses.
700     if (OMPDeclareSimdDeclAttr::ConvertStrToBranchStateTy(ClauseName, Out)) {
701       if (BS != OMPDeclareSimdDeclAttr::BS_Undefined && BS != Out) {
702         P.Diag(Tok, diag::err_omp_declare_simd_inbranch_notinbranch)
703             << ClauseName
704             << OMPDeclareSimdDeclAttr::ConvertBranchStateTyToStr(BS) << BSRange;
705         IsError = true;
706       }
707       BS = Out;
708       BSRange = SourceRange(Tok.getLocation(), Tok.getEndLoc());
709       P.ConsumeToken();
710     } else if (ClauseName.equals("simdlen")) {
711       if (SimdLen.isUsable()) {
712         P.Diag(Tok, diag::err_omp_more_one_clause)
713             << getOpenMPDirectiveName(OMPD_declare_simd) << ClauseName << 0;
714         IsError = true;
715       }
716       P.ConsumeToken();
717       SourceLocation RLoc;
718       SimdLen = P.ParseOpenMPParensExpr(ClauseName, RLoc);
719       if (SimdLen.isInvalid())
720         IsError = true;
721     } else {
722       OpenMPClauseKind CKind = getOpenMPClauseKind(ClauseName);
723       if (CKind == OMPC_uniform || CKind == OMPC_aligned ||
724           CKind == OMPC_linear) {
725         Parser::OpenMPVarListDataTy Data;
726         SmallVectorImpl<Expr *> *Vars = &Uniforms;
727         if (CKind == OMPC_aligned)
728           Vars = &Aligneds;
729         else if (CKind == OMPC_linear)
730           Vars = &Linears;
731 
732         P.ConsumeToken();
733         if (P.ParseOpenMPVarList(OMPD_declare_simd,
734                                  getOpenMPClauseKind(ClauseName), *Vars, Data))
735           IsError = true;
736         if (CKind == OMPC_aligned) {
737           Alignments.append(Aligneds.size() - Alignments.size(), Data.TailExpr);
738         } else if (CKind == OMPC_linear) {
739           if (P.getActions().CheckOpenMPLinearModifier(Data.LinKind,
740                                                        Data.DepLinMapLoc))
741             Data.LinKind = OMPC_LINEAR_val;
742           LinModifiers.append(Linears.size() - LinModifiers.size(),
743                               Data.LinKind);
744           Steps.append(Linears.size() - Steps.size(), Data.TailExpr);
745         }
746       } else
747         // TODO: add parsing of other clauses.
748         break;
749     }
750     // Skip ',' if any.
751     if (Tok.is(tok::comma))
752       P.ConsumeToken();
753   }
754   return IsError;
755 }
756 
757 /// Parse clauses for '#pragma omp declare simd'.
758 Parser::DeclGroupPtrTy
759 Parser::ParseOMPDeclareSimdClauses(Parser::DeclGroupPtrTy Ptr,
760                                    CachedTokens &Toks, SourceLocation Loc) {
761   PP.EnterToken(Tok, /*IsReinject*/ true);
762   PP.EnterTokenStream(Toks, /*DisableMacroExpansion=*/true,
763                       /*IsReinject*/ true);
764   // Consume the previously pushed token.
765   ConsumeAnyToken(/*ConsumeCodeCompletionTok=*/true);
766   ConsumeAnyToken(/*ConsumeCodeCompletionTok=*/true);
767 
768   FNContextRAII FnContext(*this, Ptr);
769   OMPDeclareSimdDeclAttr::BranchStateTy BS =
770       OMPDeclareSimdDeclAttr::BS_Undefined;
771   ExprResult Simdlen;
772   SmallVector<Expr *, 4> Uniforms;
773   SmallVector<Expr *, 4> Aligneds;
774   SmallVector<Expr *, 4> Alignments;
775   SmallVector<Expr *, 4> Linears;
776   SmallVector<unsigned, 4> LinModifiers;
777   SmallVector<Expr *, 4> Steps;
778   bool IsError =
779       parseDeclareSimdClauses(*this, BS, Simdlen, Uniforms, Aligneds,
780                               Alignments, Linears, LinModifiers, Steps);
781   // Need to check for extra tokens.
782   if (Tok.isNot(tok::annot_pragma_openmp_end)) {
783     Diag(Tok, diag::warn_omp_extra_tokens_at_eol)
784         << getOpenMPDirectiveName(OMPD_declare_simd);
785     while (Tok.isNot(tok::annot_pragma_openmp_end))
786       ConsumeAnyToken();
787   }
788   // Skip the last annot_pragma_openmp_end.
789   SourceLocation EndLoc = ConsumeAnnotationToken();
790   if (IsError)
791     return Ptr;
792   return Actions.ActOnOpenMPDeclareSimdDirective(
793       Ptr, BS, Simdlen.get(), Uniforms, Aligneds, Alignments, Linears,
794       LinModifiers, Steps, SourceRange(Loc, EndLoc));
795 }
796 
797 /// Parse optional 'score' '(' <expr> ')' ':'.
798 static ExprResult parseContextScore(Parser &P) {
799   ExprResult ScoreExpr;
800   SmallString<16> Buffer;
801   StringRef SelectorName =
802       P.getPreprocessor().getSpelling(P.getCurToken(), Buffer);
803   if (!SelectorName.equals("score"))
804     return ScoreExpr;
805   (void)P.ConsumeToken();
806   SourceLocation RLoc;
807   ScoreExpr = P.ParseOpenMPParensExpr(SelectorName, RLoc);
808   // Parse ':'
809   if (P.getCurToken().is(tok::colon))
810     (void)P.ConsumeAnyToken();
811   else
812     P.Diag(P.getCurToken(), diag::warn_pragma_expected_colon)
813         << "context selector score clause";
814   return ScoreExpr;
815 }
816 
817 /// Parse context selector for 'implementation' selector set:
818 /// 'vendor' '(' [ 'score' '(' <score _expr> ')' ':' ] <vendor> { ',' <vendor> }
819 /// ')'
820 static void parseImplementationSelector(
821     Parser &P, SourceLocation Loc, llvm::StringMap<SourceLocation> &UsedCtx,
822     llvm::function_ref<void(SourceRange,
823                             const Sema::OpenMPDeclareVariantCtsSelectorData &)>
824         Callback) {
825   const Token &Tok = P.getCurToken();
826   // Parse inner context selector set name, if any.
827   if (!Tok.is(tok::identifier)) {
828     P.Diag(Tok.getLocation(), diag::warn_omp_declare_variant_cs_name_expected)
829         << "implementation";
830     // Skip until either '}', ')', or end of directive.
831     while (!P.SkipUntil(tok::r_brace, tok::r_paren,
832                         tok::annot_pragma_openmp_end, Parser::StopBeforeMatch))
833       ;
834     return;
835   }
836   SmallString<16> Buffer;
837   StringRef CtxSelectorName = P.getPreprocessor().getSpelling(Tok, Buffer);
838   auto Res = UsedCtx.try_emplace(CtxSelectorName, Tok.getLocation());
839   if (!Res.second) {
840     // OpenMP 5.0, 2.3.2 Context Selectors, Restrictions.
841     // Each trait-selector-name can only be specified once.
842     P.Diag(Tok.getLocation(), diag::err_omp_declare_variant_ctx_mutiple_use)
843         << CtxSelectorName << "implementation";
844     P.Diag(Res.first->getValue(), diag::note_omp_declare_variant_ctx_used_here)
845         << CtxSelectorName;
846   }
847   OMPDeclareVariantAttr::CtxSelectorType CSKind =
848       OMPDeclareVariantAttr::CtxUnknown;
849   (void)OMPDeclareVariantAttr::ConvertStrToCtxSelectorType(CtxSelectorName,
850                                                            CSKind);
851   (void)P.ConsumeToken();
852   switch (CSKind) {
853   case OMPDeclareVariantAttr::CtxVendor: {
854     // Parse '('.
855     BalancedDelimiterTracker T(P, tok::l_paren, tok::annot_pragma_openmp_end);
856     (void)T.expectAndConsume(diag::err_expected_lparen_after,
857                              CtxSelectorName.data());
858     const ExprResult Score = parseContextScore(P);
859     llvm::UniqueVector<llvm::SmallString<16>> Vendors;
860     do {
861       // Parse <vendor>.
862       StringRef VendorName;
863       if (Tok.is(tok::identifier)) {
864         Buffer.clear();
865         VendorName = P.getPreprocessor().getSpelling(P.getCurToken(), Buffer);
866         (void)P.ConsumeToken();
867         if (!VendorName.empty())
868           Vendors.insert(VendorName);
869       } else {
870         P.Diag(Tok.getLocation(), diag::err_omp_declare_variant_item_expected)
871             << "vendor identifier"
872             << "vendor"
873             << "implementation";
874       }
875       if (!P.TryConsumeToken(tok::comma) && Tok.isNot(tok::r_paren)) {
876         P.Diag(Tok, diag::err_expected_punc)
877             << (VendorName.empty() ? "vendor name" : VendorName);
878       }
879     } while (Tok.is(tok::identifier));
880     // Parse ')'.
881     (void)T.consumeClose();
882     if (!Vendors.empty()) {
883       SmallVector<StringRef, 4> ImplVendors(Vendors.size());
884       llvm::copy(Vendors, ImplVendors.begin());
885       Sema::OpenMPDeclareVariantCtsSelectorData Data(
886           OMPDeclareVariantAttr::CtxSetImplementation, CSKind,
887           llvm::makeMutableArrayRef(ImplVendors.begin(), ImplVendors.size()),
888           Score);
889       Callback(SourceRange(Loc, Tok.getLocation()), Data);
890     }
891     break;
892   }
893   case OMPDeclareVariantAttr::CtxUnknown:
894     P.Diag(Tok.getLocation(), diag::warn_omp_declare_variant_cs_name_expected)
895         << "implementation";
896     // Skip until either '}', ')', or end of directive.
897     while (!P.SkipUntil(tok::r_brace, tok::r_paren,
898                         tok::annot_pragma_openmp_end, Parser::StopBeforeMatch))
899       ;
900     return;
901   }
902 }
903 
904 /// Parses clauses for 'declare variant' directive.
905 /// clause:
906 /// <selector_set_name> '=' '{' <context_selectors> '}'
907 /// [ ',' <selector_set_name> '=' '{' <context_selectors> '}' ]
908 bool Parser::parseOpenMPContextSelectors(
909     SourceLocation Loc,
910     llvm::function_ref<void(SourceRange,
911                             const Sema::OpenMPDeclareVariantCtsSelectorData &)>
912         Callback) {
913   llvm::StringMap<SourceLocation> UsedCtxSets;
914   do {
915     // Parse inner context selector set name.
916     if (!Tok.is(tok::identifier)) {
917       Diag(Tok.getLocation(), diag::err_omp_declare_variant_no_ctx_selector)
918           << getOpenMPClauseName(OMPC_match);
919       return true;
920     }
921     SmallString<16> Buffer;
922     StringRef CtxSelectorSetName = PP.getSpelling(Tok, Buffer);
923     auto Res = UsedCtxSets.try_emplace(CtxSelectorSetName, Tok.getLocation());
924     if (!Res.second) {
925       // OpenMP 5.0, 2.3.2 Context Selectors, Restrictions.
926       // Each trait-set-selector-name can only be specified once.
927       Diag(Tok.getLocation(), diag::err_omp_declare_variant_ctx_set_mutiple_use)
928           << CtxSelectorSetName;
929       Diag(Res.first->getValue(),
930            diag::note_omp_declare_variant_ctx_set_used_here)
931           << CtxSelectorSetName;
932     }
933     // Parse '='.
934     (void)ConsumeToken();
935     if (Tok.isNot(tok::equal)) {
936       Diag(Tok.getLocation(), diag::err_omp_declare_variant_equal_expected)
937           << CtxSelectorSetName;
938       return true;
939     }
940     (void)ConsumeToken();
941     // TBD: add parsing of known context selectors.
942     // Unknown selector - just ignore it completely.
943     {
944       // Parse '{'.
945       BalancedDelimiterTracker TBr(*this, tok::l_brace,
946                                    tok::annot_pragma_openmp_end);
947       if (TBr.expectAndConsume(diag::err_expected_lbrace_after, "="))
948         return true;
949       OMPDeclareVariantAttr::CtxSelectorSetType CSSKind =
950           OMPDeclareVariantAttr::CtxSetUnknown;
951       (void)OMPDeclareVariantAttr::ConvertStrToCtxSelectorSetType(
952           CtxSelectorSetName, CSSKind);
953       llvm::StringMap<SourceLocation> UsedCtx;
954       do {
955         switch (CSSKind) {
956         case OMPDeclareVariantAttr::CtxSetImplementation:
957           parseImplementationSelector(*this, Loc, UsedCtx, Callback);
958           break;
959         case OMPDeclareVariantAttr::CtxSetUnknown:
960           // Skip until either '}', ')', or end of directive.
961           while (!SkipUntil(tok::r_brace, tok::r_paren,
962                             tok::annot_pragma_openmp_end, StopBeforeMatch))
963             ;
964           break;
965         }
966         const Token PrevTok = Tok;
967         if (!TryConsumeToken(tok::comma) && Tok.isNot(tok::r_brace))
968           Diag(Tok, diag::err_omp_expected_comma_brace)
969               << (PrevTok.isAnnotation() ? "context selector trait"
970                                          : PP.getSpelling(PrevTok));
971       } while (Tok.is(tok::identifier));
972       // Parse '}'.
973       (void)TBr.consumeClose();
974     }
975     // Consume ','
976     if (Tok.isNot(tok::r_paren) && Tok.isNot(tok::annot_pragma_openmp_end))
977       (void)ExpectAndConsume(tok::comma);
978   } while (Tok.isAnyIdentifier());
979   return false;
980 }
981 
982 /// Parse clauses for '#pragma omp declare variant ( variant-func-id ) clause'.
983 void Parser::ParseOMPDeclareVariantClauses(Parser::DeclGroupPtrTy Ptr,
984                                            CachedTokens &Toks,
985                                            SourceLocation Loc) {
986   PP.EnterToken(Tok, /*IsReinject*/ true);
987   PP.EnterTokenStream(Toks, /*DisableMacroExpansion=*/true,
988                       /*IsReinject*/ true);
989   // Consume the previously pushed token.
990   ConsumeAnyToken(/*ConsumeCodeCompletionTok=*/true);
991   ConsumeAnyToken(/*ConsumeCodeCompletionTok=*/true);
992 
993   FNContextRAII FnContext(*this, Ptr);
994   // Parse function declaration id.
995   SourceLocation RLoc;
996   // Parse with IsAddressOfOperand set to true to parse methods as DeclRefExprs
997   // instead of MemberExprs.
998   ExprResult AssociatedFunction =
999       ParseOpenMPParensExpr(getOpenMPDirectiveName(OMPD_declare_variant), RLoc,
1000                             /*IsAddressOfOperand=*/true);
1001   if (!AssociatedFunction.isUsable()) {
1002     if (!Tok.is(tok::annot_pragma_openmp_end))
1003       while (!SkipUntil(tok::annot_pragma_openmp_end, StopBeforeMatch))
1004         ;
1005     // Skip the last annot_pragma_openmp_end.
1006     (void)ConsumeAnnotationToken();
1007     return;
1008   }
1009   Optional<std::pair<FunctionDecl *, Expr *>> DeclVarData =
1010       Actions.checkOpenMPDeclareVariantFunction(
1011           Ptr, AssociatedFunction.get(), SourceRange(Loc, Tok.getLocation()));
1012 
1013   // Parse 'match'.
1014   OpenMPClauseKind CKind = Tok.isAnnotation()
1015                                ? OMPC_unknown
1016                                : getOpenMPClauseKind(PP.getSpelling(Tok));
1017   if (CKind != OMPC_match) {
1018     Diag(Tok.getLocation(), diag::err_omp_declare_variant_wrong_clause)
1019         << getOpenMPClauseName(OMPC_match);
1020     while (!SkipUntil(tok::annot_pragma_openmp_end, Parser::StopBeforeMatch))
1021       ;
1022     // Skip the last annot_pragma_openmp_end.
1023     (void)ConsumeAnnotationToken();
1024     return;
1025   }
1026   (void)ConsumeToken();
1027   // Parse '('.
1028   BalancedDelimiterTracker T(*this, tok::l_paren, tok::annot_pragma_openmp_end);
1029   if (T.expectAndConsume(diag::err_expected_lparen_after,
1030                          getOpenMPClauseName(OMPC_match))) {
1031     while (!SkipUntil(tok::annot_pragma_openmp_end, StopBeforeMatch))
1032       ;
1033     // Skip the last annot_pragma_openmp_end.
1034     (void)ConsumeAnnotationToken();
1035     return;
1036   }
1037 
1038   // Parse inner context selectors.
1039   if (!parseOpenMPContextSelectors(
1040           Loc, [this, &DeclVarData](
1041                    SourceRange SR,
1042                    const Sema::OpenMPDeclareVariantCtsSelectorData &Data) {
1043             if (DeclVarData.hasValue())
1044               Actions.ActOnOpenMPDeclareVariantDirective(
1045                   DeclVarData.getValue().first, DeclVarData.getValue().second,
1046                   SR, Data);
1047           })) {
1048     // Parse ')'.
1049     (void)T.consumeClose();
1050     // Need to check for extra tokens.
1051     if (Tok.isNot(tok::annot_pragma_openmp_end)) {
1052       Diag(Tok, diag::warn_omp_extra_tokens_at_eol)
1053           << getOpenMPDirectiveName(OMPD_declare_variant);
1054     }
1055   }
1056 
1057   // Skip last tokens.
1058   while (Tok.isNot(tok::annot_pragma_openmp_end))
1059     ConsumeAnyToken();
1060   // Skip the last annot_pragma_openmp_end.
1061   (void)ConsumeAnnotationToken();
1062 }
1063 
1064 /// Parsing of simple OpenMP clauses like 'default' or 'proc_bind'.
1065 ///
1066 ///    default-clause:
1067 ///         'default' '(' 'none' | 'shared' ')
1068 ///
1069 ///    proc_bind-clause:
1070 ///         'proc_bind' '(' 'master' | 'close' | 'spread' ')
1071 ///
1072 ///    device_type-clause:
1073 ///         'device_type' '(' 'host' | 'nohost' | 'any' )'
1074 namespace {
1075   struct SimpleClauseData {
1076     unsigned Type;
1077     SourceLocation Loc;
1078     SourceLocation LOpen;
1079     SourceLocation TypeLoc;
1080     SourceLocation RLoc;
1081     SimpleClauseData(unsigned Type, SourceLocation Loc, SourceLocation LOpen,
1082                      SourceLocation TypeLoc, SourceLocation RLoc)
1083         : Type(Type), Loc(Loc), LOpen(LOpen), TypeLoc(TypeLoc), RLoc(RLoc) {}
1084   };
1085 } // anonymous namespace
1086 
1087 static Optional<SimpleClauseData>
1088 parseOpenMPSimpleClause(Parser &P, OpenMPClauseKind Kind) {
1089   const Token &Tok = P.getCurToken();
1090   SourceLocation Loc = Tok.getLocation();
1091   SourceLocation LOpen = P.ConsumeToken();
1092   // Parse '('.
1093   BalancedDelimiterTracker T(P, tok::l_paren, tok::annot_pragma_openmp_end);
1094   if (T.expectAndConsume(diag::err_expected_lparen_after,
1095                          getOpenMPClauseName(Kind)))
1096     return llvm::None;
1097 
1098   unsigned Type = getOpenMPSimpleClauseType(
1099       Kind, Tok.isAnnotation() ? "" : P.getPreprocessor().getSpelling(Tok));
1100   SourceLocation TypeLoc = Tok.getLocation();
1101   if (Tok.isNot(tok::r_paren) && Tok.isNot(tok::comma) &&
1102       Tok.isNot(tok::annot_pragma_openmp_end))
1103     P.ConsumeAnyToken();
1104 
1105   // Parse ')'.
1106   SourceLocation RLoc = Tok.getLocation();
1107   if (!T.consumeClose())
1108     RLoc = T.getCloseLocation();
1109 
1110   return SimpleClauseData(Type, Loc, LOpen, TypeLoc, RLoc);
1111 }
1112 
1113 Parser::DeclGroupPtrTy Parser::ParseOMPDeclareTargetClauses() {
1114   // OpenMP 4.5 syntax with list of entities.
1115   Sema::NamedDeclSetType SameDirectiveDecls;
1116   SmallVector<std::tuple<OMPDeclareTargetDeclAttr::MapTypeTy, SourceLocation,
1117                          NamedDecl *>,
1118               4>
1119       DeclareTargetDecls;
1120   OMPDeclareTargetDeclAttr::DevTypeTy DT = OMPDeclareTargetDeclAttr::DT_Any;
1121   SourceLocation DeviceTypeLoc;
1122   while (Tok.isNot(tok::annot_pragma_openmp_end)) {
1123     OMPDeclareTargetDeclAttr::MapTypeTy MT = OMPDeclareTargetDeclAttr::MT_To;
1124     if (Tok.is(tok::identifier)) {
1125       IdentifierInfo *II = Tok.getIdentifierInfo();
1126       StringRef ClauseName = II->getName();
1127       bool IsDeviceTypeClause =
1128           getLangOpts().OpenMP >= 50 &&
1129           getOpenMPClauseKind(ClauseName) == OMPC_device_type;
1130       // Parse 'to|link|device_type' clauses.
1131       if (!OMPDeclareTargetDeclAttr::ConvertStrToMapTypeTy(ClauseName, MT) &&
1132           !IsDeviceTypeClause) {
1133         Diag(Tok, diag::err_omp_declare_target_unexpected_clause)
1134             << ClauseName << (getLangOpts().OpenMP >= 50 ? 1 : 0);
1135         break;
1136       }
1137       // Parse 'device_type' clause and go to next clause if any.
1138       if (IsDeviceTypeClause) {
1139         Optional<SimpleClauseData> DevTypeData =
1140             parseOpenMPSimpleClause(*this, OMPC_device_type);
1141         if (DevTypeData.hasValue()) {
1142           if (DeviceTypeLoc.isValid()) {
1143             // We already saw another device_type clause, diagnose it.
1144             Diag(DevTypeData.getValue().Loc,
1145                  diag::warn_omp_more_one_device_type_clause);
1146           }
1147           switch(static_cast<OpenMPDeviceType>(DevTypeData.getValue().Type)) {
1148           case OMPC_DEVICE_TYPE_any:
1149             DT = OMPDeclareTargetDeclAttr::DT_Any;
1150             break;
1151           case OMPC_DEVICE_TYPE_host:
1152             DT = OMPDeclareTargetDeclAttr::DT_Host;
1153             break;
1154           case OMPC_DEVICE_TYPE_nohost:
1155             DT = OMPDeclareTargetDeclAttr::DT_NoHost;
1156             break;
1157           case OMPC_DEVICE_TYPE_unknown:
1158             llvm_unreachable("Unexpected device_type");
1159           }
1160           DeviceTypeLoc = DevTypeData.getValue().Loc;
1161         }
1162         continue;
1163       }
1164       ConsumeToken();
1165     }
1166     auto &&Callback = [this, MT, &DeclareTargetDecls, &SameDirectiveDecls](
1167                           CXXScopeSpec &SS, DeclarationNameInfo NameInfo) {
1168       NamedDecl *ND = Actions.lookupOpenMPDeclareTargetName(
1169           getCurScope(), SS, NameInfo, SameDirectiveDecls);
1170       if (ND)
1171         DeclareTargetDecls.emplace_back(MT, NameInfo.getLoc(), ND);
1172     };
1173     if (ParseOpenMPSimpleVarList(OMPD_declare_target, Callback,
1174                                  /*AllowScopeSpecifier=*/true))
1175       break;
1176 
1177     // Consume optional ','.
1178     if (Tok.is(tok::comma))
1179       ConsumeToken();
1180   }
1181   SkipUntil(tok::annot_pragma_openmp_end, StopBeforeMatch);
1182   ConsumeAnyToken();
1183   for (auto &MTLocDecl : DeclareTargetDecls) {
1184     OMPDeclareTargetDeclAttr::MapTypeTy MT;
1185     SourceLocation Loc;
1186     NamedDecl *ND;
1187     std::tie(MT, Loc, ND) = MTLocDecl;
1188     // device_type clause is applied only to functions.
1189     Actions.ActOnOpenMPDeclareTargetName(
1190         ND, Loc, MT, isa<VarDecl>(ND) ? OMPDeclareTargetDeclAttr::DT_Any : DT);
1191   }
1192   SmallVector<Decl *, 4> Decls(SameDirectiveDecls.begin(),
1193                                SameDirectiveDecls.end());
1194   if (Decls.empty())
1195     return DeclGroupPtrTy();
1196   return Actions.BuildDeclaratorGroup(Decls);
1197 }
1198 
1199 void Parser::ParseOMPEndDeclareTargetDirective(OpenMPDirectiveKind DKind,
1200                                                SourceLocation DTLoc) {
1201   if (DKind != OMPD_end_declare_target) {
1202     Diag(Tok, diag::err_expected_end_declare_target);
1203     Diag(DTLoc, diag::note_matching) << "'#pragma omp declare target'";
1204     return;
1205   }
1206   ConsumeAnyToken();
1207   if (Tok.isNot(tok::annot_pragma_openmp_end)) {
1208     Diag(Tok, diag::warn_omp_extra_tokens_at_eol)
1209         << getOpenMPDirectiveName(OMPD_end_declare_target);
1210     SkipUntil(tok::annot_pragma_openmp_end, StopBeforeMatch);
1211   }
1212   // Skip the last annot_pragma_openmp_end.
1213   ConsumeAnyToken();
1214 }
1215 
1216 /// Parsing of declarative OpenMP directives.
1217 ///
1218 ///       threadprivate-directive:
1219 ///         annot_pragma_openmp 'threadprivate' simple-variable-list
1220 ///         annot_pragma_openmp_end
1221 ///
1222 ///       allocate-directive:
1223 ///         annot_pragma_openmp 'allocate' simple-variable-list [<clause>]
1224 ///         annot_pragma_openmp_end
1225 ///
1226 ///       declare-reduction-directive:
1227 ///        annot_pragma_openmp 'declare' 'reduction' [...]
1228 ///        annot_pragma_openmp_end
1229 ///
1230 ///       declare-mapper-directive:
1231 ///         annot_pragma_openmp 'declare' 'mapper' '(' [<mapper-identifer> ':']
1232 ///         <type> <var> ')' [<clause>[[,] <clause>] ... ]
1233 ///         annot_pragma_openmp_end
1234 ///
1235 ///       declare-simd-directive:
1236 ///         annot_pragma_openmp 'declare simd' {<clause> [,]}
1237 ///         annot_pragma_openmp_end
1238 ///         <function declaration/definition>
1239 ///
1240 ///       requires directive:
1241 ///         annot_pragma_openmp 'requires' <clause> [[[,] <clause>] ... ]
1242 ///         annot_pragma_openmp_end
1243 ///
1244 Parser::DeclGroupPtrTy Parser::ParseOpenMPDeclarativeDirectiveWithExtDecl(
1245     AccessSpecifier &AS, ParsedAttributesWithRange &Attrs,
1246     DeclSpec::TST TagType, Decl *Tag) {
1247   assert(Tok.is(tok::annot_pragma_openmp) && "Not an OpenMP directive!");
1248   ParenBraceBracketBalancer BalancerRAIIObj(*this);
1249 
1250   SourceLocation Loc = ConsumeAnnotationToken();
1251   OpenMPDirectiveKind DKind = parseOpenMPDirectiveKind(*this);
1252 
1253   switch (DKind) {
1254   case OMPD_threadprivate: {
1255     ConsumeToken();
1256     DeclDirectiveListParserHelper Helper(this, DKind);
1257     if (!ParseOpenMPSimpleVarList(DKind, Helper,
1258                                   /*AllowScopeSpecifier=*/true)) {
1259       // The last seen token is annot_pragma_openmp_end - need to check for
1260       // extra tokens.
1261       if (Tok.isNot(tok::annot_pragma_openmp_end)) {
1262         Diag(Tok, diag::warn_omp_extra_tokens_at_eol)
1263             << getOpenMPDirectiveName(DKind);
1264         SkipUntil(tok::annot_pragma_openmp_end, StopBeforeMatch);
1265       }
1266       // Skip the last annot_pragma_openmp_end.
1267       ConsumeAnnotationToken();
1268       return Actions.ActOnOpenMPThreadprivateDirective(Loc,
1269                                                        Helper.getIdentifiers());
1270     }
1271     break;
1272   }
1273   case OMPD_allocate: {
1274     ConsumeToken();
1275     DeclDirectiveListParserHelper Helper(this, DKind);
1276     if (!ParseOpenMPSimpleVarList(DKind, Helper,
1277                                   /*AllowScopeSpecifier=*/true)) {
1278       SmallVector<OMPClause *, 1> Clauses;
1279       if (Tok.isNot(tok::annot_pragma_openmp_end)) {
1280         SmallVector<llvm::PointerIntPair<OMPClause *, 1, bool>,
1281                     OMPC_unknown + 1>
1282             FirstClauses(OMPC_unknown + 1);
1283         while (Tok.isNot(tok::annot_pragma_openmp_end)) {
1284           OpenMPClauseKind CKind =
1285               Tok.isAnnotation() ? OMPC_unknown
1286                                  : getOpenMPClauseKind(PP.getSpelling(Tok));
1287           Actions.StartOpenMPClause(CKind);
1288           OMPClause *Clause = ParseOpenMPClause(OMPD_allocate, CKind,
1289                                                 !FirstClauses[CKind].getInt());
1290           SkipUntil(tok::comma, tok::identifier, tok::annot_pragma_openmp_end,
1291                     StopBeforeMatch);
1292           FirstClauses[CKind].setInt(true);
1293           if (Clause != nullptr)
1294             Clauses.push_back(Clause);
1295           if (Tok.is(tok::annot_pragma_openmp_end)) {
1296             Actions.EndOpenMPClause();
1297             break;
1298           }
1299           // Skip ',' if any.
1300           if (Tok.is(tok::comma))
1301             ConsumeToken();
1302           Actions.EndOpenMPClause();
1303         }
1304         // The last seen token is annot_pragma_openmp_end - need to check for
1305         // extra tokens.
1306         if (Tok.isNot(tok::annot_pragma_openmp_end)) {
1307           Diag(Tok, diag::warn_omp_extra_tokens_at_eol)
1308               << getOpenMPDirectiveName(DKind);
1309           SkipUntil(tok::annot_pragma_openmp_end, StopBeforeMatch);
1310         }
1311       }
1312       // Skip the last annot_pragma_openmp_end.
1313       ConsumeAnnotationToken();
1314       return Actions.ActOnOpenMPAllocateDirective(Loc, Helper.getIdentifiers(),
1315                                                   Clauses);
1316     }
1317     break;
1318   }
1319   case OMPD_requires: {
1320     SourceLocation StartLoc = ConsumeToken();
1321     SmallVector<OMPClause *, 5> Clauses;
1322     SmallVector<llvm::PointerIntPair<OMPClause *, 1, bool>, OMPC_unknown + 1>
1323     FirstClauses(OMPC_unknown + 1);
1324     if (Tok.is(tok::annot_pragma_openmp_end)) {
1325       Diag(Tok, diag::err_omp_expected_clause)
1326           << getOpenMPDirectiveName(OMPD_requires);
1327       break;
1328     }
1329     while (Tok.isNot(tok::annot_pragma_openmp_end)) {
1330       OpenMPClauseKind CKind = Tok.isAnnotation()
1331                                    ? OMPC_unknown
1332                                    : getOpenMPClauseKind(PP.getSpelling(Tok));
1333       Actions.StartOpenMPClause(CKind);
1334       OMPClause *Clause = ParseOpenMPClause(OMPD_requires, CKind,
1335                                             !FirstClauses[CKind].getInt());
1336       SkipUntil(tok::comma, tok::identifier, tok::annot_pragma_openmp_end,
1337                 StopBeforeMatch);
1338       FirstClauses[CKind].setInt(true);
1339       if (Clause != nullptr)
1340         Clauses.push_back(Clause);
1341       if (Tok.is(tok::annot_pragma_openmp_end)) {
1342         Actions.EndOpenMPClause();
1343         break;
1344       }
1345       // Skip ',' if any.
1346       if (Tok.is(tok::comma))
1347         ConsumeToken();
1348       Actions.EndOpenMPClause();
1349     }
1350     // Consume final annot_pragma_openmp_end
1351     if (Clauses.size() == 0) {
1352       Diag(Tok, diag::err_omp_expected_clause)
1353           << getOpenMPDirectiveName(OMPD_requires);
1354       ConsumeAnnotationToken();
1355       return nullptr;
1356     }
1357     ConsumeAnnotationToken();
1358     return Actions.ActOnOpenMPRequiresDirective(StartLoc, Clauses);
1359   }
1360   case OMPD_declare_reduction:
1361     ConsumeToken();
1362     if (DeclGroupPtrTy Res = ParseOpenMPDeclareReductionDirective(AS)) {
1363       // The last seen token is annot_pragma_openmp_end - need to check for
1364       // extra tokens.
1365       if (Tok.isNot(tok::annot_pragma_openmp_end)) {
1366         Diag(Tok, diag::warn_omp_extra_tokens_at_eol)
1367             << getOpenMPDirectiveName(OMPD_declare_reduction);
1368         while (Tok.isNot(tok::annot_pragma_openmp_end))
1369           ConsumeAnyToken();
1370       }
1371       // Skip the last annot_pragma_openmp_end.
1372       ConsumeAnnotationToken();
1373       return Res;
1374     }
1375     break;
1376   case OMPD_declare_mapper: {
1377     ConsumeToken();
1378     if (DeclGroupPtrTy Res = ParseOpenMPDeclareMapperDirective(AS)) {
1379       // Skip the last annot_pragma_openmp_end.
1380       ConsumeAnnotationToken();
1381       return Res;
1382     }
1383     break;
1384   }
1385   case OMPD_declare_variant:
1386   case OMPD_declare_simd: {
1387     // The syntax is:
1388     // { #pragma omp declare {simd|variant} }
1389     // <function-declaration-or-definition>
1390     //
1391     CachedTokens Toks;
1392     Toks.push_back(Tok);
1393     ConsumeToken();
1394     while(Tok.isNot(tok::annot_pragma_openmp_end)) {
1395       Toks.push_back(Tok);
1396       ConsumeAnyToken();
1397     }
1398     Toks.push_back(Tok);
1399     ConsumeAnyToken();
1400 
1401     DeclGroupPtrTy Ptr;
1402     if (Tok.is(tok::annot_pragma_openmp)) {
1403       Ptr = ParseOpenMPDeclarativeDirectiveWithExtDecl(AS, Attrs, TagType, Tag);
1404     } else if (Tok.isNot(tok::r_brace) && !isEofOrEom()) {
1405       // Here we expect to see some function declaration.
1406       if (AS == AS_none) {
1407         assert(TagType == DeclSpec::TST_unspecified);
1408         MaybeParseCXX11Attributes(Attrs);
1409         ParsingDeclSpec PDS(*this);
1410         Ptr = ParseExternalDeclaration(Attrs, &PDS);
1411       } else {
1412         Ptr =
1413             ParseCXXClassMemberDeclarationWithPragmas(AS, Attrs, TagType, Tag);
1414       }
1415     }
1416     if (!Ptr) {
1417       Diag(Loc, diag::err_omp_decl_in_declare_simd_variant)
1418           << (DKind == OMPD_declare_simd ? 0 : 1);
1419       return DeclGroupPtrTy();
1420     }
1421     if (DKind == OMPD_declare_simd)
1422       return ParseOMPDeclareSimdClauses(Ptr, Toks, Loc);
1423     assert(DKind == OMPD_declare_variant &&
1424            "Expected declare variant directive only");
1425     ParseOMPDeclareVariantClauses(Ptr, Toks, Loc);
1426     return Ptr;
1427   }
1428   case OMPD_declare_target: {
1429     SourceLocation DTLoc = ConsumeAnyToken();
1430     if (Tok.isNot(tok::annot_pragma_openmp_end)) {
1431       return ParseOMPDeclareTargetClauses();
1432     }
1433 
1434     // Skip the last annot_pragma_openmp_end.
1435     ConsumeAnyToken();
1436 
1437     if (!Actions.ActOnStartOpenMPDeclareTargetDirective(DTLoc))
1438       return DeclGroupPtrTy();
1439 
1440     llvm::SmallVector<Decl *, 4>  Decls;
1441     DKind = parseOpenMPDirectiveKind(*this);
1442     while (DKind != OMPD_end_declare_target && Tok.isNot(tok::eof) &&
1443            Tok.isNot(tok::r_brace)) {
1444       DeclGroupPtrTy Ptr;
1445       // Here we expect to see some function declaration.
1446       if (AS == AS_none) {
1447         assert(TagType == DeclSpec::TST_unspecified);
1448         MaybeParseCXX11Attributes(Attrs);
1449         ParsingDeclSpec PDS(*this);
1450         Ptr = ParseExternalDeclaration(Attrs, &PDS);
1451       } else {
1452         Ptr =
1453             ParseCXXClassMemberDeclarationWithPragmas(AS, Attrs, TagType, Tag);
1454       }
1455       if (Ptr) {
1456         DeclGroupRef Ref = Ptr.get();
1457         Decls.append(Ref.begin(), Ref.end());
1458       }
1459       if (Tok.isAnnotation() && Tok.is(tok::annot_pragma_openmp)) {
1460         TentativeParsingAction TPA(*this);
1461         ConsumeAnnotationToken();
1462         DKind = parseOpenMPDirectiveKind(*this);
1463         if (DKind != OMPD_end_declare_target)
1464           TPA.Revert();
1465         else
1466           TPA.Commit();
1467       }
1468     }
1469 
1470     ParseOMPEndDeclareTargetDirective(DKind, DTLoc);
1471     Actions.ActOnFinishOpenMPDeclareTargetDirective();
1472     return Actions.BuildDeclaratorGroup(Decls);
1473   }
1474   case OMPD_unknown:
1475     Diag(Tok, diag::err_omp_unknown_directive);
1476     break;
1477   case OMPD_parallel:
1478   case OMPD_simd:
1479   case OMPD_task:
1480   case OMPD_taskyield:
1481   case OMPD_barrier:
1482   case OMPD_taskwait:
1483   case OMPD_taskgroup:
1484   case OMPD_flush:
1485   case OMPD_for:
1486   case OMPD_for_simd:
1487   case OMPD_sections:
1488   case OMPD_section:
1489   case OMPD_single:
1490   case OMPD_master:
1491   case OMPD_ordered:
1492   case OMPD_critical:
1493   case OMPD_parallel_for:
1494   case OMPD_parallel_for_simd:
1495   case OMPD_parallel_sections:
1496   case OMPD_atomic:
1497   case OMPD_target:
1498   case OMPD_teams:
1499   case OMPD_cancellation_point:
1500   case OMPD_cancel:
1501   case OMPD_target_data:
1502   case OMPD_target_enter_data:
1503   case OMPD_target_exit_data:
1504   case OMPD_target_parallel:
1505   case OMPD_target_parallel_for:
1506   case OMPD_taskloop:
1507   case OMPD_taskloop_simd:
1508   case OMPD_master_taskloop:
1509   case OMPD_master_taskloop_simd:
1510   case OMPD_parallel_master_taskloop:
1511   case OMPD_parallel_master_taskloop_simd:
1512   case OMPD_distribute:
1513   case OMPD_end_declare_target:
1514   case OMPD_target_update:
1515   case OMPD_distribute_parallel_for:
1516   case OMPD_distribute_parallel_for_simd:
1517   case OMPD_distribute_simd:
1518   case OMPD_target_parallel_for_simd:
1519   case OMPD_target_simd:
1520   case OMPD_teams_distribute:
1521   case OMPD_teams_distribute_simd:
1522   case OMPD_teams_distribute_parallel_for_simd:
1523   case OMPD_teams_distribute_parallel_for:
1524   case OMPD_target_teams:
1525   case OMPD_target_teams_distribute:
1526   case OMPD_target_teams_distribute_parallel_for:
1527   case OMPD_target_teams_distribute_parallel_for_simd:
1528   case OMPD_target_teams_distribute_simd:
1529     Diag(Tok, diag::err_omp_unexpected_directive)
1530         << 1 << getOpenMPDirectiveName(DKind);
1531     break;
1532   }
1533   while (Tok.isNot(tok::annot_pragma_openmp_end))
1534     ConsumeAnyToken();
1535   ConsumeAnyToken();
1536   return nullptr;
1537 }
1538 
1539 /// Parsing of declarative or executable OpenMP directives.
1540 ///
1541 ///       threadprivate-directive:
1542 ///         annot_pragma_openmp 'threadprivate' simple-variable-list
1543 ///         annot_pragma_openmp_end
1544 ///
1545 ///       allocate-directive:
1546 ///         annot_pragma_openmp 'allocate' simple-variable-list
1547 ///         annot_pragma_openmp_end
1548 ///
1549 ///       declare-reduction-directive:
1550 ///         annot_pragma_openmp 'declare' 'reduction' '(' <reduction_id> ':'
1551 ///         <type> {',' <type>} ':' <expression> ')' ['initializer' '('
1552 ///         ('omp_priv' '=' <expression>|<function_call>) ')']
1553 ///         annot_pragma_openmp_end
1554 ///
1555 ///       declare-mapper-directive:
1556 ///         annot_pragma_openmp 'declare' 'mapper' '(' [<mapper-identifer> ':']
1557 ///         <type> <var> ')' [<clause>[[,] <clause>] ... ]
1558 ///         annot_pragma_openmp_end
1559 ///
1560 ///       executable-directive:
1561 ///         annot_pragma_openmp 'parallel' | 'simd' | 'for' | 'sections' |
1562 ///         'section' | 'single' | 'master' | 'critical' [ '(' <name> ')' ] |
1563 ///         'parallel for' | 'parallel sections' | 'task' | 'taskyield' |
1564 ///         'barrier' | 'taskwait' | 'flush' | 'ordered' | 'atomic' |
1565 ///         'for simd' | 'parallel for simd' | 'target' | 'target data' |
1566 ///         'taskgroup' | 'teams' | 'taskloop' | 'taskloop simd' | 'master
1567 ///         taskloop' | 'master taskloop simd' | 'parallel master taskloop' |
1568 ///         'parallel master taskloop simd' | 'distribute' | 'target enter data'
1569 ///         | 'target exit data' | 'target parallel' | 'target parallel for' |
1570 ///         'target update' | 'distribute parallel for' | 'distribute paralle
1571 ///         for simd' | 'distribute simd' | 'target parallel for simd' | 'target
1572 ///         simd' | 'teams distribute' | 'teams distribute simd' | 'teams
1573 ///         distribute parallel for simd' | 'teams distribute parallel for' |
1574 ///         'target teams' | 'target teams distribute' | 'target teams
1575 ///         distribute parallel for' | 'target teams distribute parallel for
1576 ///         simd' | 'target teams distribute simd' {clause}
1577 ///         annot_pragma_openmp_end
1578 ///
1579 StmtResult
1580 Parser::ParseOpenMPDeclarativeOrExecutableDirective(ParsedStmtContext StmtCtx) {
1581   assert(Tok.is(tok::annot_pragma_openmp) && "Not an OpenMP directive!");
1582   ParenBraceBracketBalancer BalancerRAIIObj(*this);
1583   SmallVector<OMPClause *, 5> Clauses;
1584   SmallVector<llvm::PointerIntPair<OMPClause *, 1, bool>, OMPC_unknown + 1>
1585   FirstClauses(OMPC_unknown + 1);
1586   unsigned ScopeFlags = Scope::FnScope | Scope::DeclScope |
1587                         Scope::CompoundStmtScope | Scope::OpenMPDirectiveScope;
1588   SourceLocation Loc = ConsumeAnnotationToken(), EndLoc;
1589   OpenMPDirectiveKind DKind = parseOpenMPDirectiveKind(*this);
1590   OpenMPDirectiveKind CancelRegion = OMPD_unknown;
1591   // Name of critical directive.
1592   DeclarationNameInfo DirName;
1593   StmtResult Directive = StmtError();
1594   bool HasAssociatedStatement = true;
1595   bool FlushHasClause = false;
1596 
1597   switch (DKind) {
1598   case OMPD_threadprivate: {
1599     // FIXME: Should this be permitted in C++?
1600     if ((StmtCtx & ParsedStmtContext::AllowDeclarationsInC) ==
1601         ParsedStmtContext()) {
1602       Diag(Tok, diag::err_omp_immediate_directive)
1603           << getOpenMPDirectiveName(DKind) << 0;
1604     }
1605     ConsumeToken();
1606     DeclDirectiveListParserHelper Helper(this, DKind);
1607     if (!ParseOpenMPSimpleVarList(DKind, Helper,
1608                                   /*AllowScopeSpecifier=*/false)) {
1609       // The last seen token is annot_pragma_openmp_end - need to check for
1610       // extra tokens.
1611       if (Tok.isNot(tok::annot_pragma_openmp_end)) {
1612         Diag(Tok, diag::warn_omp_extra_tokens_at_eol)
1613             << getOpenMPDirectiveName(DKind);
1614         SkipUntil(tok::annot_pragma_openmp_end, StopBeforeMatch);
1615       }
1616       DeclGroupPtrTy Res = Actions.ActOnOpenMPThreadprivateDirective(
1617           Loc, Helper.getIdentifiers());
1618       Directive = Actions.ActOnDeclStmt(Res, Loc, Tok.getLocation());
1619     }
1620     SkipUntil(tok::annot_pragma_openmp_end);
1621     break;
1622   }
1623   case OMPD_allocate: {
1624     // FIXME: Should this be permitted in C++?
1625     if ((StmtCtx & ParsedStmtContext::AllowDeclarationsInC) ==
1626         ParsedStmtContext()) {
1627       Diag(Tok, diag::err_omp_immediate_directive)
1628           << getOpenMPDirectiveName(DKind) << 0;
1629     }
1630     ConsumeToken();
1631     DeclDirectiveListParserHelper Helper(this, DKind);
1632     if (!ParseOpenMPSimpleVarList(DKind, Helper,
1633                                   /*AllowScopeSpecifier=*/false)) {
1634       SmallVector<OMPClause *, 1> Clauses;
1635       if (Tok.isNot(tok::annot_pragma_openmp_end)) {
1636         SmallVector<llvm::PointerIntPair<OMPClause *, 1, bool>,
1637                     OMPC_unknown + 1>
1638             FirstClauses(OMPC_unknown + 1);
1639         while (Tok.isNot(tok::annot_pragma_openmp_end)) {
1640           OpenMPClauseKind CKind =
1641               Tok.isAnnotation() ? OMPC_unknown
1642                                  : getOpenMPClauseKind(PP.getSpelling(Tok));
1643           Actions.StartOpenMPClause(CKind);
1644           OMPClause *Clause = ParseOpenMPClause(OMPD_allocate, CKind,
1645                                                 !FirstClauses[CKind].getInt());
1646           SkipUntil(tok::comma, tok::identifier, tok::annot_pragma_openmp_end,
1647                     StopBeforeMatch);
1648           FirstClauses[CKind].setInt(true);
1649           if (Clause != nullptr)
1650             Clauses.push_back(Clause);
1651           if (Tok.is(tok::annot_pragma_openmp_end)) {
1652             Actions.EndOpenMPClause();
1653             break;
1654           }
1655           // Skip ',' if any.
1656           if (Tok.is(tok::comma))
1657             ConsumeToken();
1658           Actions.EndOpenMPClause();
1659         }
1660         // The last seen token is annot_pragma_openmp_end - need to check for
1661         // extra tokens.
1662         if (Tok.isNot(tok::annot_pragma_openmp_end)) {
1663           Diag(Tok, diag::warn_omp_extra_tokens_at_eol)
1664               << getOpenMPDirectiveName(DKind);
1665           SkipUntil(tok::annot_pragma_openmp_end, StopBeforeMatch);
1666         }
1667       }
1668       DeclGroupPtrTy Res = Actions.ActOnOpenMPAllocateDirective(
1669           Loc, Helper.getIdentifiers(), Clauses);
1670       Directive = Actions.ActOnDeclStmt(Res, Loc, Tok.getLocation());
1671     }
1672     SkipUntil(tok::annot_pragma_openmp_end);
1673     break;
1674   }
1675   case OMPD_declare_reduction:
1676     ConsumeToken();
1677     if (DeclGroupPtrTy Res =
1678             ParseOpenMPDeclareReductionDirective(/*AS=*/AS_none)) {
1679       // The last seen token is annot_pragma_openmp_end - need to check for
1680       // extra tokens.
1681       if (Tok.isNot(tok::annot_pragma_openmp_end)) {
1682         Diag(Tok, diag::warn_omp_extra_tokens_at_eol)
1683             << getOpenMPDirectiveName(OMPD_declare_reduction);
1684         while (Tok.isNot(tok::annot_pragma_openmp_end))
1685           ConsumeAnyToken();
1686       }
1687       ConsumeAnyToken();
1688       Directive = Actions.ActOnDeclStmt(Res, Loc, Tok.getLocation());
1689     } else {
1690       SkipUntil(tok::annot_pragma_openmp_end);
1691     }
1692     break;
1693   case OMPD_declare_mapper: {
1694     ConsumeToken();
1695     if (DeclGroupPtrTy Res =
1696             ParseOpenMPDeclareMapperDirective(/*AS=*/AS_none)) {
1697       // Skip the last annot_pragma_openmp_end.
1698       ConsumeAnnotationToken();
1699       Directive = Actions.ActOnDeclStmt(Res, Loc, Tok.getLocation());
1700     } else {
1701       SkipUntil(tok::annot_pragma_openmp_end);
1702     }
1703     break;
1704   }
1705   case OMPD_flush:
1706     if (PP.LookAhead(0).is(tok::l_paren)) {
1707       FlushHasClause = true;
1708       // Push copy of the current token back to stream to properly parse
1709       // pseudo-clause OMPFlushClause.
1710       PP.EnterToken(Tok, /*IsReinject*/ true);
1711     }
1712     LLVM_FALLTHROUGH;
1713   case OMPD_taskyield:
1714   case OMPD_barrier:
1715   case OMPD_taskwait:
1716   case OMPD_cancellation_point:
1717   case OMPD_cancel:
1718   case OMPD_target_enter_data:
1719   case OMPD_target_exit_data:
1720   case OMPD_target_update:
1721     if ((StmtCtx & ParsedStmtContext::AllowStandaloneOpenMPDirectives) ==
1722         ParsedStmtContext()) {
1723       Diag(Tok, diag::err_omp_immediate_directive)
1724           << getOpenMPDirectiveName(DKind) << 0;
1725     }
1726     HasAssociatedStatement = false;
1727     // Fall through for further analysis.
1728     LLVM_FALLTHROUGH;
1729   case OMPD_parallel:
1730   case OMPD_simd:
1731   case OMPD_for:
1732   case OMPD_for_simd:
1733   case OMPD_sections:
1734   case OMPD_single:
1735   case OMPD_section:
1736   case OMPD_master:
1737   case OMPD_critical:
1738   case OMPD_parallel_for:
1739   case OMPD_parallel_for_simd:
1740   case OMPD_parallel_sections:
1741   case OMPD_task:
1742   case OMPD_ordered:
1743   case OMPD_atomic:
1744   case OMPD_target:
1745   case OMPD_teams:
1746   case OMPD_taskgroup:
1747   case OMPD_target_data:
1748   case OMPD_target_parallel:
1749   case OMPD_target_parallel_for:
1750   case OMPD_taskloop:
1751   case OMPD_taskloop_simd:
1752   case OMPD_master_taskloop:
1753   case OMPD_master_taskloop_simd:
1754   case OMPD_parallel_master_taskloop:
1755   case OMPD_parallel_master_taskloop_simd:
1756   case OMPD_distribute:
1757   case OMPD_distribute_parallel_for:
1758   case OMPD_distribute_parallel_for_simd:
1759   case OMPD_distribute_simd:
1760   case OMPD_target_parallel_for_simd:
1761   case OMPD_target_simd:
1762   case OMPD_teams_distribute:
1763   case OMPD_teams_distribute_simd:
1764   case OMPD_teams_distribute_parallel_for_simd:
1765   case OMPD_teams_distribute_parallel_for:
1766   case OMPD_target_teams:
1767   case OMPD_target_teams_distribute:
1768   case OMPD_target_teams_distribute_parallel_for:
1769   case OMPD_target_teams_distribute_parallel_for_simd:
1770   case OMPD_target_teams_distribute_simd: {
1771     ConsumeToken();
1772     // Parse directive name of the 'critical' directive if any.
1773     if (DKind == OMPD_critical) {
1774       BalancedDelimiterTracker T(*this, tok::l_paren,
1775                                  tok::annot_pragma_openmp_end);
1776       if (!T.consumeOpen()) {
1777         if (Tok.isAnyIdentifier()) {
1778           DirName =
1779               DeclarationNameInfo(Tok.getIdentifierInfo(), Tok.getLocation());
1780           ConsumeAnyToken();
1781         } else {
1782           Diag(Tok, diag::err_omp_expected_identifier_for_critical);
1783         }
1784         T.consumeClose();
1785       }
1786     } else if (DKind == OMPD_cancellation_point || DKind == OMPD_cancel) {
1787       CancelRegion = parseOpenMPDirectiveKind(*this);
1788       if (Tok.isNot(tok::annot_pragma_openmp_end))
1789         ConsumeToken();
1790     }
1791 
1792     if (isOpenMPLoopDirective(DKind))
1793       ScopeFlags |= Scope::OpenMPLoopDirectiveScope;
1794     if (isOpenMPSimdDirective(DKind))
1795       ScopeFlags |= Scope::OpenMPSimdDirectiveScope;
1796     ParseScope OMPDirectiveScope(this, ScopeFlags);
1797     Actions.StartOpenMPDSABlock(DKind, DirName, Actions.getCurScope(), Loc);
1798 
1799     while (Tok.isNot(tok::annot_pragma_openmp_end)) {
1800       OpenMPClauseKind CKind =
1801           Tok.isAnnotation()
1802               ? OMPC_unknown
1803               : FlushHasClause ? OMPC_flush
1804                                : getOpenMPClauseKind(PP.getSpelling(Tok));
1805       Actions.StartOpenMPClause(CKind);
1806       FlushHasClause = false;
1807       OMPClause *Clause =
1808           ParseOpenMPClause(DKind, CKind, !FirstClauses[CKind].getInt());
1809       FirstClauses[CKind].setInt(true);
1810       if (Clause) {
1811         FirstClauses[CKind].setPointer(Clause);
1812         Clauses.push_back(Clause);
1813       }
1814 
1815       // Skip ',' if any.
1816       if (Tok.is(tok::comma))
1817         ConsumeToken();
1818       Actions.EndOpenMPClause();
1819     }
1820     // End location of the directive.
1821     EndLoc = Tok.getLocation();
1822     // Consume final annot_pragma_openmp_end.
1823     ConsumeAnnotationToken();
1824 
1825     // OpenMP [2.13.8, ordered Construct, Syntax]
1826     // If the depend clause is specified, the ordered construct is a stand-alone
1827     // directive.
1828     if (DKind == OMPD_ordered && FirstClauses[OMPC_depend].getInt()) {
1829       if ((StmtCtx & ParsedStmtContext::AllowStandaloneOpenMPDirectives) ==
1830           ParsedStmtContext()) {
1831         Diag(Loc, diag::err_omp_immediate_directive)
1832             << getOpenMPDirectiveName(DKind) << 1
1833             << getOpenMPClauseName(OMPC_depend);
1834       }
1835       HasAssociatedStatement = false;
1836     }
1837 
1838     StmtResult AssociatedStmt;
1839     if (HasAssociatedStatement) {
1840       // The body is a block scope like in Lambdas and Blocks.
1841       Actions.ActOnOpenMPRegionStart(DKind, getCurScope());
1842       // FIXME: We create a bogus CompoundStmt scope to hold the contents of
1843       // the captured region. Code elsewhere assumes that any FunctionScopeInfo
1844       // should have at least one compound statement scope within it.
1845       AssociatedStmt = (Sema::CompoundScopeRAII(Actions), ParseStatement());
1846       AssociatedStmt = Actions.ActOnOpenMPRegionEnd(AssociatedStmt, Clauses);
1847     } else if (DKind == OMPD_target_update || DKind == OMPD_target_enter_data ||
1848                DKind == OMPD_target_exit_data) {
1849       Actions.ActOnOpenMPRegionStart(DKind, getCurScope());
1850       AssociatedStmt = (Sema::CompoundScopeRAII(Actions),
1851                         Actions.ActOnCompoundStmt(Loc, Loc, llvm::None,
1852                                                   /*isStmtExpr=*/false));
1853       AssociatedStmt = Actions.ActOnOpenMPRegionEnd(AssociatedStmt, Clauses);
1854     }
1855     Directive = Actions.ActOnOpenMPExecutableDirective(
1856         DKind, DirName, CancelRegion, Clauses, AssociatedStmt.get(), Loc,
1857         EndLoc);
1858 
1859     // Exit scope.
1860     Actions.EndOpenMPDSABlock(Directive.get());
1861     OMPDirectiveScope.Exit();
1862     break;
1863   }
1864   case OMPD_declare_simd:
1865   case OMPD_declare_target:
1866   case OMPD_end_declare_target:
1867   case OMPD_requires:
1868   case OMPD_declare_variant:
1869     Diag(Tok, diag::err_omp_unexpected_directive)
1870         << 1 << getOpenMPDirectiveName(DKind);
1871     SkipUntil(tok::annot_pragma_openmp_end);
1872     break;
1873   case OMPD_unknown:
1874     Diag(Tok, diag::err_omp_unknown_directive);
1875     SkipUntil(tok::annot_pragma_openmp_end);
1876     break;
1877   }
1878   return Directive;
1879 }
1880 
1881 // Parses simple list:
1882 //   simple-variable-list:
1883 //         '(' id-expression {, id-expression} ')'
1884 //
1885 bool Parser::ParseOpenMPSimpleVarList(
1886     OpenMPDirectiveKind Kind,
1887     const llvm::function_ref<void(CXXScopeSpec &, DeclarationNameInfo)> &
1888         Callback,
1889     bool AllowScopeSpecifier) {
1890   // Parse '('.
1891   BalancedDelimiterTracker T(*this, tok::l_paren, tok::annot_pragma_openmp_end);
1892   if (T.expectAndConsume(diag::err_expected_lparen_after,
1893                          getOpenMPDirectiveName(Kind)))
1894     return true;
1895   bool IsCorrect = true;
1896   bool NoIdentIsFound = true;
1897 
1898   // Read tokens while ')' or annot_pragma_openmp_end is not found.
1899   while (Tok.isNot(tok::r_paren) && Tok.isNot(tok::annot_pragma_openmp_end)) {
1900     CXXScopeSpec SS;
1901     UnqualifiedId Name;
1902     // Read var name.
1903     Token PrevTok = Tok;
1904     NoIdentIsFound = false;
1905 
1906     if (AllowScopeSpecifier && getLangOpts().CPlusPlus &&
1907         ParseOptionalCXXScopeSpecifier(SS, nullptr, false)) {
1908       IsCorrect = false;
1909       SkipUntil(tok::comma, tok::r_paren, tok::annot_pragma_openmp_end,
1910                 StopBeforeMatch);
1911     } else if (ParseUnqualifiedId(SS, false, false, false, false, nullptr,
1912                                   nullptr, Name)) {
1913       IsCorrect = false;
1914       SkipUntil(tok::comma, tok::r_paren, tok::annot_pragma_openmp_end,
1915                 StopBeforeMatch);
1916     } else if (Tok.isNot(tok::comma) && Tok.isNot(tok::r_paren) &&
1917                Tok.isNot(tok::annot_pragma_openmp_end)) {
1918       IsCorrect = false;
1919       SkipUntil(tok::comma, tok::r_paren, tok::annot_pragma_openmp_end,
1920                 StopBeforeMatch);
1921       Diag(PrevTok.getLocation(), diag::err_expected)
1922           << tok::identifier
1923           << SourceRange(PrevTok.getLocation(), PrevTokLocation);
1924     } else {
1925       Callback(SS, Actions.GetNameFromUnqualifiedId(Name));
1926     }
1927     // Consume ','.
1928     if (Tok.is(tok::comma)) {
1929       ConsumeToken();
1930     }
1931   }
1932 
1933   if (NoIdentIsFound) {
1934     Diag(Tok, diag::err_expected) << tok::identifier;
1935     IsCorrect = false;
1936   }
1937 
1938   // Parse ')'.
1939   IsCorrect = !T.consumeClose() && IsCorrect;
1940 
1941   return !IsCorrect;
1942 }
1943 
1944 /// Parsing of OpenMP clauses.
1945 ///
1946 ///    clause:
1947 ///       if-clause | final-clause | num_threads-clause | safelen-clause |
1948 ///       default-clause | private-clause | firstprivate-clause | shared-clause
1949 ///       | linear-clause | aligned-clause | collapse-clause |
1950 ///       lastprivate-clause | reduction-clause | proc_bind-clause |
1951 ///       schedule-clause | copyin-clause | copyprivate-clause | untied-clause |
1952 ///       mergeable-clause | flush-clause | read-clause | write-clause |
1953 ///       update-clause | capture-clause | seq_cst-clause | device-clause |
1954 ///       simdlen-clause | threads-clause | simd-clause | num_teams-clause |
1955 ///       thread_limit-clause | priority-clause | grainsize-clause |
1956 ///       nogroup-clause | num_tasks-clause | hint-clause | to-clause |
1957 ///       from-clause | is_device_ptr-clause | task_reduction-clause |
1958 ///       in_reduction-clause | allocator-clause | allocate-clause
1959 ///
1960 OMPClause *Parser::ParseOpenMPClause(OpenMPDirectiveKind DKind,
1961                                      OpenMPClauseKind CKind, bool FirstClause) {
1962   OMPClause *Clause = nullptr;
1963   bool ErrorFound = false;
1964   bool WrongDirective = false;
1965   // Check if clause is allowed for the given directive.
1966   if (CKind != OMPC_unknown && !isAllowedClauseForDirective(DKind, CKind)) {
1967     Diag(Tok, diag::err_omp_unexpected_clause) << getOpenMPClauseName(CKind)
1968                                                << getOpenMPDirectiveName(DKind);
1969     ErrorFound = true;
1970     WrongDirective = true;
1971   }
1972 
1973   switch (CKind) {
1974   case OMPC_final:
1975   case OMPC_num_threads:
1976   case OMPC_safelen:
1977   case OMPC_simdlen:
1978   case OMPC_collapse:
1979   case OMPC_ordered:
1980   case OMPC_device:
1981   case OMPC_num_teams:
1982   case OMPC_thread_limit:
1983   case OMPC_priority:
1984   case OMPC_grainsize:
1985   case OMPC_num_tasks:
1986   case OMPC_hint:
1987   case OMPC_allocator:
1988     // OpenMP [2.5, Restrictions]
1989     //  At most one num_threads clause can appear on the directive.
1990     // OpenMP [2.8.1, simd construct, Restrictions]
1991     //  Only one safelen  clause can appear on a simd directive.
1992     //  Only one simdlen  clause can appear on a simd directive.
1993     //  Only one collapse clause can appear on a simd directive.
1994     // OpenMP [2.9.1, target data construct, Restrictions]
1995     //  At most one device clause can appear on the directive.
1996     // OpenMP [2.11.1, task Construct, Restrictions]
1997     //  At most one if clause can appear on the directive.
1998     //  At most one final clause can appear on the directive.
1999     // OpenMP [teams Construct, Restrictions]
2000     //  At most one num_teams clause can appear on the directive.
2001     //  At most one thread_limit clause can appear on the directive.
2002     // OpenMP [2.9.1, task Construct, Restrictions]
2003     // At most one priority clause can appear on the directive.
2004     // OpenMP [2.9.2, taskloop Construct, Restrictions]
2005     // At most one grainsize clause can appear on the directive.
2006     // OpenMP [2.9.2, taskloop Construct, Restrictions]
2007     // At most one num_tasks clause can appear on the directive.
2008     // OpenMP [2.11.3, allocate Directive, Restrictions]
2009     // At most one allocator clause can appear on the directive.
2010     if (!FirstClause) {
2011       Diag(Tok, diag::err_omp_more_one_clause)
2012           << getOpenMPDirectiveName(DKind) << getOpenMPClauseName(CKind) << 0;
2013       ErrorFound = true;
2014     }
2015 
2016     if (CKind == OMPC_ordered && PP.LookAhead(/*N=*/0).isNot(tok::l_paren))
2017       Clause = ParseOpenMPClause(CKind, WrongDirective);
2018     else
2019       Clause = ParseOpenMPSingleExprClause(CKind, WrongDirective);
2020     break;
2021   case OMPC_default:
2022   case OMPC_proc_bind:
2023   case OMPC_atomic_default_mem_order:
2024     // OpenMP [2.14.3.1, Restrictions]
2025     //  Only a single default clause may be specified on a parallel, task or
2026     //  teams directive.
2027     // OpenMP [2.5, parallel Construct, Restrictions]
2028     //  At most one proc_bind clause can appear on the directive.
2029     // OpenMP [5.0, Requires directive, Restrictions]
2030     //  At most one atomic_default_mem_order clause can appear
2031     //  on the directive
2032     if (!FirstClause) {
2033       Diag(Tok, diag::err_omp_more_one_clause)
2034           << getOpenMPDirectiveName(DKind) << getOpenMPClauseName(CKind) << 0;
2035       ErrorFound = true;
2036     }
2037 
2038     Clause = ParseOpenMPSimpleClause(CKind, WrongDirective);
2039     break;
2040   case OMPC_schedule:
2041   case OMPC_dist_schedule:
2042   case OMPC_defaultmap:
2043     // OpenMP [2.7.1, Restrictions, p. 3]
2044     //  Only one schedule clause can appear on a loop directive.
2045     // OpenMP [2.10.4, Restrictions, p. 106]
2046     //  At most one defaultmap clause can appear on the directive.
2047     if (!FirstClause) {
2048       Diag(Tok, diag::err_omp_more_one_clause)
2049           << getOpenMPDirectiveName(DKind) << getOpenMPClauseName(CKind) << 0;
2050       ErrorFound = true;
2051     }
2052     LLVM_FALLTHROUGH;
2053 
2054   case OMPC_if:
2055     Clause = ParseOpenMPSingleExprWithArgClause(CKind, WrongDirective);
2056     break;
2057   case OMPC_nowait:
2058   case OMPC_untied:
2059   case OMPC_mergeable:
2060   case OMPC_read:
2061   case OMPC_write:
2062   case OMPC_update:
2063   case OMPC_capture:
2064   case OMPC_seq_cst:
2065   case OMPC_threads:
2066   case OMPC_simd:
2067   case OMPC_nogroup:
2068   case OMPC_unified_address:
2069   case OMPC_unified_shared_memory:
2070   case OMPC_reverse_offload:
2071   case OMPC_dynamic_allocators:
2072     // OpenMP [2.7.1, Restrictions, p. 9]
2073     //  Only one ordered clause can appear on a loop directive.
2074     // OpenMP [2.7.1, Restrictions, C/C++, p. 4]
2075     //  Only one nowait clause can appear on a for directive.
2076     // OpenMP [5.0, Requires directive, Restrictions]
2077     //   Each of the requires clauses can appear at most once on the directive.
2078     if (!FirstClause) {
2079       Diag(Tok, diag::err_omp_more_one_clause)
2080           << getOpenMPDirectiveName(DKind) << getOpenMPClauseName(CKind) << 0;
2081       ErrorFound = true;
2082     }
2083 
2084     Clause = ParseOpenMPClause(CKind, WrongDirective);
2085     break;
2086   case OMPC_private:
2087   case OMPC_firstprivate:
2088   case OMPC_lastprivate:
2089   case OMPC_shared:
2090   case OMPC_reduction:
2091   case OMPC_task_reduction:
2092   case OMPC_in_reduction:
2093   case OMPC_linear:
2094   case OMPC_aligned:
2095   case OMPC_copyin:
2096   case OMPC_copyprivate:
2097   case OMPC_flush:
2098   case OMPC_depend:
2099   case OMPC_map:
2100   case OMPC_to:
2101   case OMPC_from:
2102   case OMPC_use_device_ptr:
2103   case OMPC_is_device_ptr:
2104   case OMPC_allocate:
2105     Clause = ParseOpenMPVarListClause(DKind, CKind, WrongDirective);
2106     break;
2107   case OMPC_device_type:
2108   case OMPC_unknown:
2109     Diag(Tok, diag::warn_omp_extra_tokens_at_eol)
2110         << getOpenMPDirectiveName(DKind);
2111     SkipUntil(tok::annot_pragma_openmp_end, StopBeforeMatch);
2112     break;
2113   case OMPC_threadprivate:
2114   case OMPC_uniform:
2115   case OMPC_match:
2116     if (!WrongDirective)
2117       Diag(Tok, diag::err_omp_unexpected_clause)
2118           << getOpenMPClauseName(CKind) << getOpenMPDirectiveName(DKind);
2119     SkipUntil(tok::comma, tok::annot_pragma_openmp_end, StopBeforeMatch);
2120     break;
2121   }
2122   return ErrorFound ? nullptr : Clause;
2123 }
2124 
2125 /// Parses simple expression in parens for single-expression clauses of OpenMP
2126 /// constructs.
2127 /// \param RLoc Returned location of right paren.
2128 ExprResult Parser::ParseOpenMPParensExpr(StringRef ClauseName,
2129                                          SourceLocation &RLoc,
2130                                          bool IsAddressOfOperand) {
2131   BalancedDelimiterTracker T(*this, tok::l_paren, tok::annot_pragma_openmp_end);
2132   if (T.expectAndConsume(diag::err_expected_lparen_after, ClauseName.data()))
2133     return ExprError();
2134 
2135   SourceLocation ELoc = Tok.getLocation();
2136   ExprResult LHS(ParseCastExpression(
2137       /*isUnaryExpression=*/false, IsAddressOfOperand, NotTypeCast));
2138   ExprResult Val(ParseRHSOfBinaryExpression(LHS, prec::Conditional));
2139   Val = Actions.ActOnFinishFullExpr(Val.get(), ELoc, /*DiscardedValue*/ false);
2140 
2141   // Parse ')'.
2142   RLoc = Tok.getLocation();
2143   if (!T.consumeClose())
2144     RLoc = T.getCloseLocation();
2145 
2146   return Val;
2147 }
2148 
2149 /// Parsing of OpenMP clauses with single expressions like 'final',
2150 /// 'collapse', 'safelen', 'num_threads', 'simdlen', 'num_teams',
2151 /// 'thread_limit', 'simdlen', 'priority', 'grainsize', 'num_tasks' or 'hint'.
2152 ///
2153 ///    final-clause:
2154 ///      'final' '(' expression ')'
2155 ///
2156 ///    num_threads-clause:
2157 ///      'num_threads' '(' expression ')'
2158 ///
2159 ///    safelen-clause:
2160 ///      'safelen' '(' expression ')'
2161 ///
2162 ///    simdlen-clause:
2163 ///      'simdlen' '(' expression ')'
2164 ///
2165 ///    collapse-clause:
2166 ///      'collapse' '(' expression ')'
2167 ///
2168 ///    priority-clause:
2169 ///      'priority' '(' expression ')'
2170 ///
2171 ///    grainsize-clause:
2172 ///      'grainsize' '(' expression ')'
2173 ///
2174 ///    num_tasks-clause:
2175 ///      'num_tasks' '(' expression ')'
2176 ///
2177 ///    hint-clause:
2178 ///      'hint' '(' expression ')'
2179 ///
2180 ///    allocator-clause:
2181 ///      'allocator' '(' expression ')'
2182 ///
2183 OMPClause *Parser::ParseOpenMPSingleExprClause(OpenMPClauseKind Kind,
2184                                                bool ParseOnly) {
2185   SourceLocation Loc = ConsumeToken();
2186   SourceLocation LLoc = Tok.getLocation();
2187   SourceLocation RLoc;
2188 
2189   ExprResult Val = ParseOpenMPParensExpr(getOpenMPClauseName(Kind), RLoc);
2190 
2191   if (Val.isInvalid())
2192     return nullptr;
2193 
2194   if (ParseOnly)
2195     return nullptr;
2196   return Actions.ActOnOpenMPSingleExprClause(Kind, Val.get(), Loc, LLoc, RLoc);
2197 }
2198 
2199 /// Parsing of simple OpenMP clauses like 'default' or 'proc_bind'.
2200 ///
2201 ///    default-clause:
2202 ///         'default' '(' 'none' | 'shared' ')
2203 ///
2204 ///    proc_bind-clause:
2205 ///         'proc_bind' '(' 'master' | 'close' | 'spread' ')
2206 ///
2207 OMPClause *Parser::ParseOpenMPSimpleClause(OpenMPClauseKind Kind,
2208                                            bool ParseOnly) {
2209   llvm::Optional<SimpleClauseData> Val = parseOpenMPSimpleClause(*this, Kind);
2210   if (!Val || ParseOnly)
2211     return nullptr;
2212   return Actions.ActOnOpenMPSimpleClause(
2213       Kind, Val.getValue().Type, Val.getValue().TypeLoc, Val.getValue().LOpen,
2214       Val.getValue().Loc, Val.getValue().RLoc);
2215 }
2216 
2217 /// Parsing of OpenMP clauses like 'ordered'.
2218 ///
2219 ///    ordered-clause:
2220 ///         'ordered'
2221 ///
2222 ///    nowait-clause:
2223 ///         'nowait'
2224 ///
2225 ///    untied-clause:
2226 ///         'untied'
2227 ///
2228 ///    mergeable-clause:
2229 ///         'mergeable'
2230 ///
2231 ///    read-clause:
2232 ///         'read'
2233 ///
2234 ///    threads-clause:
2235 ///         'threads'
2236 ///
2237 ///    simd-clause:
2238 ///         'simd'
2239 ///
2240 ///    nogroup-clause:
2241 ///         'nogroup'
2242 ///
2243 OMPClause *Parser::ParseOpenMPClause(OpenMPClauseKind Kind, bool ParseOnly) {
2244   SourceLocation Loc = Tok.getLocation();
2245   ConsumeAnyToken();
2246 
2247   if (ParseOnly)
2248     return nullptr;
2249   return Actions.ActOnOpenMPClause(Kind, Loc, Tok.getLocation());
2250 }
2251 
2252 
2253 /// Parsing of OpenMP clauses with single expressions and some additional
2254 /// argument like 'schedule' or 'dist_schedule'.
2255 ///
2256 ///    schedule-clause:
2257 ///      'schedule' '(' [ modifier [ ',' modifier ] ':' ] kind [',' expression ]
2258 ///      ')'
2259 ///
2260 ///    if-clause:
2261 ///      'if' '(' [ directive-name-modifier ':' ] expression ')'
2262 ///
2263 ///    defaultmap:
2264 ///      'defaultmap' '(' modifier ':' kind ')'
2265 ///
2266 OMPClause *Parser::ParseOpenMPSingleExprWithArgClause(OpenMPClauseKind Kind,
2267                                                       bool ParseOnly) {
2268   SourceLocation Loc = ConsumeToken();
2269   SourceLocation DelimLoc;
2270   // Parse '('.
2271   BalancedDelimiterTracker T(*this, tok::l_paren, tok::annot_pragma_openmp_end);
2272   if (T.expectAndConsume(diag::err_expected_lparen_after,
2273                          getOpenMPClauseName(Kind)))
2274     return nullptr;
2275 
2276   ExprResult Val;
2277   SmallVector<unsigned, 4> Arg;
2278   SmallVector<SourceLocation, 4> KLoc;
2279   if (Kind == OMPC_schedule) {
2280     enum { Modifier1, Modifier2, ScheduleKind, NumberOfElements };
2281     Arg.resize(NumberOfElements);
2282     KLoc.resize(NumberOfElements);
2283     Arg[Modifier1] = OMPC_SCHEDULE_MODIFIER_unknown;
2284     Arg[Modifier2] = OMPC_SCHEDULE_MODIFIER_unknown;
2285     Arg[ScheduleKind] = OMPC_SCHEDULE_unknown;
2286     unsigned KindModifier = getOpenMPSimpleClauseType(
2287         Kind, Tok.isAnnotation() ? "" : PP.getSpelling(Tok));
2288     if (KindModifier > OMPC_SCHEDULE_unknown) {
2289       // Parse 'modifier'
2290       Arg[Modifier1] = KindModifier;
2291       KLoc[Modifier1] = Tok.getLocation();
2292       if (Tok.isNot(tok::r_paren) && Tok.isNot(tok::comma) &&
2293           Tok.isNot(tok::annot_pragma_openmp_end))
2294         ConsumeAnyToken();
2295       if (Tok.is(tok::comma)) {
2296         // Parse ',' 'modifier'
2297         ConsumeAnyToken();
2298         KindModifier = getOpenMPSimpleClauseType(
2299             Kind, Tok.isAnnotation() ? "" : PP.getSpelling(Tok));
2300         Arg[Modifier2] = KindModifier > OMPC_SCHEDULE_unknown
2301                              ? KindModifier
2302                              : (unsigned)OMPC_SCHEDULE_unknown;
2303         KLoc[Modifier2] = Tok.getLocation();
2304         if (Tok.isNot(tok::r_paren) && Tok.isNot(tok::comma) &&
2305             Tok.isNot(tok::annot_pragma_openmp_end))
2306           ConsumeAnyToken();
2307       }
2308       // Parse ':'
2309       if (Tok.is(tok::colon))
2310         ConsumeAnyToken();
2311       else
2312         Diag(Tok, diag::warn_pragma_expected_colon) << "schedule modifier";
2313       KindModifier = getOpenMPSimpleClauseType(
2314           Kind, Tok.isAnnotation() ? "" : PP.getSpelling(Tok));
2315     }
2316     Arg[ScheduleKind] = KindModifier;
2317     KLoc[ScheduleKind] = Tok.getLocation();
2318     if (Tok.isNot(tok::r_paren) && Tok.isNot(tok::comma) &&
2319         Tok.isNot(tok::annot_pragma_openmp_end))
2320       ConsumeAnyToken();
2321     if ((Arg[ScheduleKind] == OMPC_SCHEDULE_static ||
2322          Arg[ScheduleKind] == OMPC_SCHEDULE_dynamic ||
2323          Arg[ScheduleKind] == OMPC_SCHEDULE_guided) &&
2324         Tok.is(tok::comma))
2325       DelimLoc = ConsumeAnyToken();
2326   } else if (Kind == OMPC_dist_schedule) {
2327     Arg.push_back(getOpenMPSimpleClauseType(
2328         Kind, Tok.isAnnotation() ? "" : PP.getSpelling(Tok)));
2329     KLoc.push_back(Tok.getLocation());
2330     if (Tok.isNot(tok::r_paren) && Tok.isNot(tok::comma) &&
2331         Tok.isNot(tok::annot_pragma_openmp_end))
2332       ConsumeAnyToken();
2333     if (Arg.back() == OMPC_DIST_SCHEDULE_static && Tok.is(tok::comma))
2334       DelimLoc = ConsumeAnyToken();
2335   } else if (Kind == OMPC_defaultmap) {
2336     // Get a defaultmap modifier
2337     Arg.push_back(getOpenMPSimpleClauseType(
2338         Kind, Tok.isAnnotation() ? "" : PP.getSpelling(Tok)));
2339     KLoc.push_back(Tok.getLocation());
2340     if (Tok.isNot(tok::r_paren) && Tok.isNot(tok::comma) &&
2341         Tok.isNot(tok::annot_pragma_openmp_end))
2342       ConsumeAnyToken();
2343     // Parse ':'
2344     if (Tok.is(tok::colon))
2345       ConsumeAnyToken();
2346     else if (Arg.back() != OMPC_DEFAULTMAP_MODIFIER_unknown)
2347       Diag(Tok, diag::warn_pragma_expected_colon) << "defaultmap modifier";
2348     // Get a defaultmap kind
2349     Arg.push_back(getOpenMPSimpleClauseType(
2350         Kind, Tok.isAnnotation() ? "" : PP.getSpelling(Tok)));
2351     KLoc.push_back(Tok.getLocation());
2352     if (Tok.isNot(tok::r_paren) && Tok.isNot(tok::comma) &&
2353         Tok.isNot(tok::annot_pragma_openmp_end))
2354       ConsumeAnyToken();
2355   } else {
2356     assert(Kind == OMPC_if);
2357     KLoc.push_back(Tok.getLocation());
2358     TentativeParsingAction TPA(*this);
2359     Arg.push_back(parseOpenMPDirectiveKind(*this));
2360     if (Arg.back() != OMPD_unknown) {
2361       ConsumeToken();
2362       if (Tok.is(tok::colon) && getLangOpts().OpenMP > 40) {
2363         TPA.Commit();
2364         DelimLoc = ConsumeToken();
2365       } else {
2366         TPA.Revert();
2367         Arg.back() = OMPD_unknown;
2368       }
2369     } else {
2370       TPA.Revert();
2371     }
2372   }
2373 
2374   bool NeedAnExpression = (Kind == OMPC_schedule && DelimLoc.isValid()) ||
2375                           (Kind == OMPC_dist_schedule && DelimLoc.isValid()) ||
2376                           Kind == OMPC_if;
2377   if (NeedAnExpression) {
2378     SourceLocation ELoc = Tok.getLocation();
2379     ExprResult LHS(ParseCastExpression(false, false, NotTypeCast));
2380     Val = ParseRHSOfBinaryExpression(LHS, prec::Conditional);
2381     Val =
2382         Actions.ActOnFinishFullExpr(Val.get(), ELoc, /*DiscardedValue*/ false);
2383   }
2384 
2385   // Parse ')'.
2386   SourceLocation RLoc = Tok.getLocation();
2387   if (!T.consumeClose())
2388     RLoc = T.getCloseLocation();
2389 
2390   if (NeedAnExpression && Val.isInvalid())
2391     return nullptr;
2392 
2393   if (ParseOnly)
2394     return nullptr;
2395   return Actions.ActOnOpenMPSingleExprWithArgClause(
2396       Kind, Arg, Val.get(), Loc, T.getOpenLocation(), KLoc, DelimLoc, RLoc);
2397 }
2398 
2399 static bool ParseReductionId(Parser &P, CXXScopeSpec &ReductionIdScopeSpec,
2400                              UnqualifiedId &ReductionId) {
2401   if (ReductionIdScopeSpec.isEmpty()) {
2402     auto OOK = OO_None;
2403     switch (P.getCurToken().getKind()) {
2404     case tok::plus:
2405       OOK = OO_Plus;
2406       break;
2407     case tok::minus:
2408       OOK = OO_Minus;
2409       break;
2410     case tok::star:
2411       OOK = OO_Star;
2412       break;
2413     case tok::amp:
2414       OOK = OO_Amp;
2415       break;
2416     case tok::pipe:
2417       OOK = OO_Pipe;
2418       break;
2419     case tok::caret:
2420       OOK = OO_Caret;
2421       break;
2422     case tok::ampamp:
2423       OOK = OO_AmpAmp;
2424       break;
2425     case tok::pipepipe:
2426       OOK = OO_PipePipe;
2427       break;
2428     default:
2429       break;
2430     }
2431     if (OOK != OO_None) {
2432       SourceLocation OpLoc = P.ConsumeToken();
2433       SourceLocation SymbolLocations[] = {OpLoc, OpLoc, SourceLocation()};
2434       ReductionId.setOperatorFunctionId(OpLoc, OOK, SymbolLocations);
2435       return false;
2436     }
2437   }
2438   return P.ParseUnqualifiedId(ReductionIdScopeSpec, /*EnteringContext*/ false,
2439                               /*AllowDestructorName*/ false,
2440                               /*AllowConstructorName*/ false,
2441                               /*AllowDeductionGuide*/ false,
2442                               nullptr, nullptr, ReductionId);
2443 }
2444 
2445 /// Checks if the token is a valid map-type-modifier.
2446 static OpenMPMapModifierKind isMapModifier(Parser &P) {
2447   Token Tok = P.getCurToken();
2448   if (!Tok.is(tok::identifier))
2449     return OMPC_MAP_MODIFIER_unknown;
2450 
2451   Preprocessor &PP = P.getPreprocessor();
2452   OpenMPMapModifierKind TypeModifier = static_cast<OpenMPMapModifierKind>(
2453       getOpenMPSimpleClauseType(OMPC_map, PP.getSpelling(Tok)));
2454   return TypeModifier;
2455 }
2456 
2457 /// Parse the mapper modifier in map, to, and from clauses.
2458 bool Parser::parseMapperModifier(OpenMPVarListDataTy &Data) {
2459   // Parse '('.
2460   BalancedDelimiterTracker T(*this, tok::l_paren, tok::colon);
2461   if (T.expectAndConsume(diag::err_expected_lparen_after, "mapper")) {
2462     SkipUntil(tok::colon, tok::r_paren, tok::annot_pragma_openmp_end,
2463               StopBeforeMatch);
2464     return true;
2465   }
2466   // Parse mapper-identifier
2467   if (getLangOpts().CPlusPlus)
2468     ParseOptionalCXXScopeSpecifier(Data.ReductionOrMapperIdScopeSpec,
2469                                    /*ObjectType=*/nullptr,
2470                                    /*EnteringContext=*/false);
2471   if (Tok.isNot(tok::identifier) && Tok.isNot(tok::kw_default)) {
2472     Diag(Tok.getLocation(), diag::err_omp_mapper_illegal_identifier);
2473     SkipUntil(tok::colon, tok::r_paren, tok::annot_pragma_openmp_end,
2474               StopBeforeMatch);
2475     return true;
2476   }
2477   auto &DeclNames = Actions.getASTContext().DeclarationNames;
2478   Data.ReductionOrMapperId = DeclarationNameInfo(
2479       DeclNames.getIdentifier(Tok.getIdentifierInfo()), Tok.getLocation());
2480   ConsumeToken();
2481   // Parse ')'.
2482   return T.consumeClose();
2483 }
2484 
2485 /// Parse map-type-modifiers in map clause.
2486 /// map([ [map-type-modifier[,] [map-type-modifier[,] ...] map-type : ] list)
2487 /// where, map-type-modifier ::= always | close | mapper(mapper-identifier)
2488 bool Parser::parseMapTypeModifiers(OpenMPVarListDataTy &Data) {
2489   while (getCurToken().isNot(tok::colon)) {
2490     OpenMPMapModifierKind TypeModifier = isMapModifier(*this);
2491     if (TypeModifier == OMPC_MAP_MODIFIER_always ||
2492         TypeModifier == OMPC_MAP_MODIFIER_close) {
2493       Data.MapTypeModifiers.push_back(TypeModifier);
2494       Data.MapTypeModifiersLoc.push_back(Tok.getLocation());
2495       ConsumeToken();
2496     } else if (TypeModifier == OMPC_MAP_MODIFIER_mapper) {
2497       Data.MapTypeModifiers.push_back(TypeModifier);
2498       Data.MapTypeModifiersLoc.push_back(Tok.getLocation());
2499       ConsumeToken();
2500       if (parseMapperModifier(Data))
2501         return true;
2502     } else {
2503       // For the case of unknown map-type-modifier or a map-type.
2504       // Map-type is followed by a colon; the function returns when it
2505       // encounters a token followed by a colon.
2506       if (Tok.is(tok::comma)) {
2507         Diag(Tok, diag::err_omp_map_type_modifier_missing);
2508         ConsumeToken();
2509         continue;
2510       }
2511       // Potential map-type token as it is followed by a colon.
2512       if (PP.LookAhead(0).is(tok::colon))
2513         return false;
2514       Diag(Tok, diag::err_omp_unknown_map_type_modifier);
2515       ConsumeToken();
2516     }
2517     if (getCurToken().is(tok::comma))
2518       ConsumeToken();
2519   }
2520   return false;
2521 }
2522 
2523 /// Checks if the token is a valid map-type.
2524 static OpenMPMapClauseKind isMapType(Parser &P) {
2525   Token Tok = P.getCurToken();
2526   // The map-type token can be either an identifier or the C++ delete keyword.
2527   if (!Tok.isOneOf(tok::identifier, tok::kw_delete))
2528     return OMPC_MAP_unknown;
2529   Preprocessor &PP = P.getPreprocessor();
2530   OpenMPMapClauseKind MapType = static_cast<OpenMPMapClauseKind>(
2531       getOpenMPSimpleClauseType(OMPC_map, PP.getSpelling(Tok)));
2532   return MapType;
2533 }
2534 
2535 /// Parse map-type in map clause.
2536 /// map([ [map-type-modifier[,] [map-type-modifier[,] ...] map-type : ] list)
2537 /// where, map-type ::= to | from | tofrom | alloc | release | delete
2538 static void parseMapType(Parser &P, Parser::OpenMPVarListDataTy &Data) {
2539   Token Tok = P.getCurToken();
2540   if (Tok.is(tok::colon)) {
2541     P.Diag(Tok, diag::err_omp_map_type_missing);
2542     return;
2543   }
2544   Data.MapType = isMapType(P);
2545   if (Data.MapType == OMPC_MAP_unknown)
2546     P.Diag(Tok, diag::err_omp_unknown_map_type);
2547   P.ConsumeToken();
2548 }
2549 
2550 /// Parses clauses with list.
2551 bool Parser::ParseOpenMPVarList(OpenMPDirectiveKind DKind,
2552                                 OpenMPClauseKind Kind,
2553                                 SmallVectorImpl<Expr *> &Vars,
2554                                 OpenMPVarListDataTy &Data) {
2555   UnqualifiedId UnqualifiedReductionId;
2556   bool InvalidReductionId = false;
2557   bool IsInvalidMapperModifier = false;
2558 
2559   // Parse '('.
2560   BalancedDelimiterTracker T(*this, tok::l_paren, tok::annot_pragma_openmp_end);
2561   if (T.expectAndConsume(diag::err_expected_lparen_after,
2562                          getOpenMPClauseName(Kind)))
2563     return true;
2564 
2565   bool NeedRParenForLinear = false;
2566   BalancedDelimiterTracker LinearT(*this, tok::l_paren,
2567                                   tok::annot_pragma_openmp_end);
2568   // Handle reduction-identifier for reduction clause.
2569   if (Kind == OMPC_reduction || Kind == OMPC_task_reduction ||
2570       Kind == OMPC_in_reduction) {
2571     ColonProtectionRAIIObject ColonRAII(*this);
2572     if (getLangOpts().CPlusPlus)
2573       ParseOptionalCXXScopeSpecifier(Data.ReductionOrMapperIdScopeSpec,
2574                                      /*ObjectType=*/nullptr,
2575                                      /*EnteringContext=*/false);
2576     InvalidReductionId = ParseReductionId(
2577         *this, Data.ReductionOrMapperIdScopeSpec, UnqualifiedReductionId);
2578     if (InvalidReductionId) {
2579       SkipUntil(tok::colon, tok::r_paren, tok::annot_pragma_openmp_end,
2580                 StopBeforeMatch);
2581     }
2582     if (Tok.is(tok::colon))
2583       Data.ColonLoc = ConsumeToken();
2584     else
2585       Diag(Tok, diag::warn_pragma_expected_colon) << "reduction identifier";
2586     if (!InvalidReductionId)
2587       Data.ReductionOrMapperId =
2588           Actions.GetNameFromUnqualifiedId(UnqualifiedReductionId);
2589   } else if (Kind == OMPC_depend) {
2590   // Handle dependency type for depend clause.
2591     ColonProtectionRAIIObject ColonRAII(*this);
2592     Data.DepKind =
2593         static_cast<OpenMPDependClauseKind>(getOpenMPSimpleClauseType(
2594             Kind, Tok.is(tok::identifier) ? PP.getSpelling(Tok) : ""));
2595     Data.DepLinMapLoc = Tok.getLocation();
2596 
2597     if (Data.DepKind == OMPC_DEPEND_unknown) {
2598       SkipUntil(tok::colon, tok::r_paren, tok::annot_pragma_openmp_end,
2599                 StopBeforeMatch);
2600     } else {
2601       ConsumeToken();
2602       // Special processing for depend(source) clause.
2603       if (DKind == OMPD_ordered && Data.DepKind == OMPC_DEPEND_source) {
2604         // Parse ')'.
2605         T.consumeClose();
2606         return false;
2607       }
2608     }
2609     if (Tok.is(tok::colon)) {
2610       Data.ColonLoc = ConsumeToken();
2611     } else {
2612       Diag(Tok, DKind == OMPD_ordered ? diag::warn_pragma_expected_colon_r_paren
2613                                       : diag::warn_pragma_expected_colon)
2614           << "dependency type";
2615     }
2616   } else if (Kind == OMPC_linear) {
2617     // Try to parse modifier if any.
2618     if (Tok.is(tok::identifier) && PP.LookAhead(0).is(tok::l_paren)) {
2619       Data.LinKind = static_cast<OpenMPLinearClauseKind>(
2620           getOpenMPSimpleClauseType(Kind, PP.getSpelling(Tok)));
2621       Data.DepLinMapLoc = ConsumeToken();
2622       LinearT.consumeOpen();
2623       NeedRParenForLinear = true;
2624     }
2625   } else if (Kind == OMPC_map) {
2626     // Handle map type for map clause.
2627     ColonProtectionRAIIObject ColonRAII(*this);
2628 
2629     // The first identifier may be a list item, a map-type or a
2630     // map-type-modifier. The map-type can also be delete which has the same
2631     // spelling of the C++ delete keyword.
2632     Data.DepLinMapLoc = Tok.getLocation();
2633 
2634     // Check for presence of a colon in the map clause.
2635     TentativeParsingAction TPA(*this);
2636     bool ColonPresent = false;
2637     if (SkipUntil(tok::colon, tok::r_paren, tok::annot_pragma_openmp_end,
2638         StopBeforeMatch)) {
2639       if (Tok.is(tok::colon))
2640         ColonPresent = true;
2641     }
2642     TPA.Revert();
2643     // Only parse map-type-modifier[s] and map-type if a colon is present in
2644     // the map clause.
2645     if (ColonPresent) {
2646       IsInvalidMapperModifier = parseMapTypeModifiers(Data);
2647       if (!IsInvalidMapperModifier)
2648         parseMapType(*this, Data);
2649       else
2650         SkipUntil(tok::colon, tok::annot_pragma_openmp_end, StopBeforeMatch);
2651     }
2652     if (Data.MapType == OMPC_MAP_unknown) {
2653       Data.MapType = OMPC_MAP_tofrom;
2654       Data.IsMapTypeImplicit = true;
2655     }
2656 
2657     if (Tok.is(tok::colon))
2658       Data.ColonLoc = ConsumeToken();
2659   } else if (Kind == OMPC_to || Kind == OMPC_from) {
2660     if (Tok.is(tok::identifier)) {
2661       bool IsMapperModifier = false;
2662       if (Kind == OMPC_to) {
2663         auto Modifier = static_cast<OpenMPToModifierKind>(
2664             getOpenMPSimpleClauseType(Kind, PP.getSpelling(Tok)));
2665         if (Modifier == OMPC_TO_MODIFIER_mapper)
2666           IsMapperModifier = true;
2667       } else {
2668         auto Modifier = static_cast<OpenMPFromModifierKind>(
2669             getOpenMPSimpleClauseType(Kind, PP.getSpelling(Tok)));
2670         if (Modifier == OMPC_FROM_MODIFIER_mapper)
2671           IsMapperModifier = true;
2672       }
2673       if (IsMapperModifier) {
2674         // Parse the mapper modifier.
2675         ConsumeToken();
2676         IsInvalidMapperModifier = parseMapperModifier(Data);
2677         if (Tok.isNot(tok::colon)) {
2678           if (!IsInvalidMapperModifier)
2679             Diag(Tok, diag::warn_pragma_expected_colon) << ")";
2680           SkipUntil(tok::colon, tok::r_paren, tok::annot_pragma_openmp_end,
2681                     StopBeforeMatch);
2682         }
2683         // Consume ':'.
2684         if (Tok.is(tok::colon))
2685           ConsumeToken();
2686       }
2687     }
2688   } else if (Kind == OMPC_allocate) {
2689     // Handle optional allocator expression followed by colon delimiter.
2690     ColonProtectionRAIIObject ColonRAII(*this);
2691     TentativeParsingAction TPA(*this);
2692     ExprResult Tail =
2693         Actions.CorrectDelayedTyposInExpr(ParseAssignmentExpression());
2694     Tail = Actions.ActOnFinishFullExpr(Tail.get(), T.getOpenLocation(),
2695                                        /*DiscardedValue=*/false);
2696     if (Tail.isUsable()) {
2697       if (Tok.is(tok::colon)) {
2698         Data.TailExpr = Tail.get();
2699         Data.ColonLoc = ConsumeToken();
2700         TPA.Commit();
2701       } else {
2702         // colon not found, no allocator specified, parse only list of
2703         // variables.
2704         TPA.Revert();
2705       }
2706     } else {
2707       // Parsing was unsuccessfull, revert and skip to the end of clause or
2708       // directive.
2709       TPA.Revert();
2710       SkipUntil(tok::comma, tok::r_paren, tok::annot_pragma_openmp_end,
2711                 StopBeforeMatch);
2712     }
2713   }
2714 
2715   bool IsComma =
2716       (Kind != OMPC_reduction && Kind != OMPC_task_reduction &&
2717        Kind != OMPC_in_reduction && Kind != OMPC_depend && Kind != OMPC_map) ||
2718       (Kind == OMPC_reduction && !InvalidReductionId) ||
2719       (Kind == OMPC_map && Data.MapType != OMPC_MAP_unknown) ||
2720       (Kind == OMPC_depend && Data.DepKind != OMPC_DEPEND_unknown);
2721   const bool MayHaveTail = (Kind == OMPC_linear || Kind == OMPC_aligned);
2722   while (IsComma || (Tok.isNot(tok::r_paren) && Tok.isNot(tok::colon) &&
2723                      Tok.isNot(tok::annot_pragma_openmp_end))) {
2724     ColonProtectionRAIIObject ColonRAII(*this, MayHaveTail);
2725     // Parse variable
2726     ExprResult VarExpr =
2727         Actions.CorrectDelayedTyposInExpr(ParseAssignmentExpression());
2728     if (VarExpr.isUsable()) {
2729       Vars.push_back(VarExpr.get());
2730     } else {
2731       SkipUntil(tok::comma, tok::r_paren, tok::annot_pragma_openmp_end,
2732                 StopBeforeMatch);
2733     }
2734     // Skip ',' if any
2735     IsComma = Tok.is(tok::comma);
2736     if (IsComma)
2737       ConsumeToken();
2738     else if (Tok.isNot(tok::r_paren) &&
2739              Tok.isNot(tok::annot_pragma_openmp_end) &&
2740              (!MayHaveTail || Tok.isNot(tok::colon)))
2741       Diag(Tok, diag::err_omp_expected_punc)
2742           << ((Kind == OMPC_flush) ? getOpenMPDirectiveName(OMPD_flush)
2743                                    : getOpenMPClauseName(Kind))
2744           << (Kind == OMPC_flush);
2745   }
2746 
2747   // Parse ')' for linear clause with modifier.
2748   if (NeedRParenForLinear)
2749     LinearT.consumeClose();
2750 
2751   // Parse ':' linear-step (or ':' alignment).
2752   const bool MustHaveTail = MayHaveTail && Tok.is(tok::colon);
2753   if (MustHaveTail) {
2754     Data.ColonLoc = Tok.getLocation();
2755     SourceLocation ELoc = ConsumeToken();
2756     ExprResult Tail = ParseAssignmentExpression();
2757     Tail =
2758         Actions.ActOnFinishFullExpr(Tail.get(), ELoc, /*DiscardedValue*/ false);
2759     if (Tail.isUsable())
2760       Data.TailExpr = Tail.get();
2761     else
2762       SkipUntil(tok::comma, tok::r_paren, tok::annot_pragma_openmp_end,
2763                 StopBeforeMatch);
2764   }
2765 
2766   // Parse ')'.
2767   Data.RLoc = Tok.getLocation();
2768   if (!T.consumeClose())
2769     Data.RLoc = T.getCloseLocation();
2770   return (Kind == OMPC_depend && Data.DepKind != OMPC_DEPEND_unknown &&
2771           Vars.empty()) ||
2772          (Kind != OMPC_depend && Kind != OMPC_map && Vars.empty()) ||
2773          (MustHaveTail && !Data.TailExpr) || InvalidReductionId ||
2774          IsInvalidMapperModifier;
2775 }
2776 
2777 /// Parsing of OpenMP clause 'private', 'firstprivate', 'lastprivate',
2778 /// 'shared', 'copyin', 'copyprivate', 'flush', 'reduction', 'task_reduction' or
2779 /// 'in_reduction'.
2780 ///
2781 ///    private-clause:
2782 ///       'private' '(' list ')'
2783 ///    firstprivate-clause:
2784 ///       'firstprivate' '(' list ')'
2785 ///    lastprivate-clause:
2786 ///       'lastprivate' '(' list ')'
2787 ///    shared-clause:
2788 ///       'shared' '(' list ')'
2789 ///    linear-clause:
2790 ///       'linear' '(' linear-list [ ':' linear-step ] ')'
2791 ///    aligned-clause:
2792 ///       'aligned' '(' list [ ':' alignment ] ')'
2793 ///    reduction-clause:
2794 ///       'reduction' '(' reduction-identifier ':' list ')'
2795 ///    task_reduction-clause:
2796 ///       'task_reduction' '(' reduction-identifier ':' list ')'
2797 ///    in_reduction-clause:
2798 ///       'in_reduction' '(' reduction-identifier ':' list ')'
2799 ///    copyprivate-clause:
2800 ///       'copyprivate' '(' list ')'
2801 ///    flush-clause:
2802 ///       'flush' '(' list ')'
2803 ///    depend-clause:
2804 ///       'depend' '(' in | out | inout : list | source ')'
2805 ///    map-clause:
2806 ///       'map' '(' [ [ always [,] ] [ close [,] ]
2807 ///          [ mapper '(' mapper-identifier ')' [,] ]
2808 ///          to | from | tofrom | alloc | release | delete ':' ] list ')';
2809 ///    to-clause:
2810 ///       'to' '(' [ mapper '(' mapper-identifier ')' ':' ] list ')'
2811 ///    from-clause:
2812 ///       'from' '(' [ mapper '(' mapper-identifier ')' ':' ] list ')'
2813 ///    use_device_ptr-clause:
2814 ///       'use_device_ptr' '(' list ')'
2815 ///    is_device_ptr-clause:
2816 ///       'is_device_ptr' '(' list ')'
2817 ///    allocate-clause:
2818 ///       'allocate' '(' [ allocator ':' ] list ')'
2819 ///
2820 /// For 'linear' clause linear-list may have the following forms:
2821 ///  list
2822 ///  modifier(list)
2823 /// where modifier is 'val' (C) or 'ref', 'val' or 'uval'(C++).
2824 OMPClause *Parser::ParseOpenMPVarListClause(OpenMPDirectiveKind DKind,
2825                                             OpenMPClauseKind Kind,
2826                                             bool ParseOnly) {
2827   SourceLocation Loc = Tok.getLocation();
2828   SourceLocation LOpen = ConsumeToken();
2829   SmallVector<Expr *, 4> Vars;
2830   OpenMPVarListDataTy Data;
2831 
2832   if (ParseOpenMPVarList(DKind, Kind, Vars, Data))
2833     return nullptr;
2834 
2835   if (ParseOnly)
2836     return nullptr;
2837   OMPVarListLocTy Locs(Loc, LOpen, Data.RLoc);
2838   return Actions.ActOnOpenMPVarListClause(
2839       Kind, Vars, Data.TailExpr, Locs, Data.ColonLoc,
2840       Data.ReductionOrMapperIdScopeSpec, Data.ReductionOrMapperId, Data.DepKind,
2841       Data.LinKind, Data.MapTypeModifiers, Data.MapTypeModifiersLoc,
2842       Data.MapType, Data.IsMapTypeImplicit, Data.DepLinMapLoc);
2843 }
2844 
2845