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/OpenMPClause.h"
15 #include "clang/AST/StmtOpenMP.h"
16 #include "clang/Basic/OpenMPKinds.h"
17 #include "clang/Basic/TargetInfo.h"
18 #include "clang/Basic/TokenKinds.h"
19 #include "clang/Parse/ParseDiagnostic.h"
20 #include "clang/Parse/Parser.h"
21 #include "clang/Parse/RAIIObjectsForParser.h"
22 #include "clang/Sema/Scope.h"
23 #include "llvm/ADT/PointerIntPair.h"
24 #include "llvm/ADT/StringSwitch.h"
25 #include "llvm/ADT/UniqueVector.h"
26 #include "llvm/Frontend/OpenMP/OMPContext.h"
27 
28 using namespace clang;
29 using namespace llvm::omp;
30 
31 //===----------------------------------------------------------------------===//
32 // OpenMP declarative directives.
33 //===----------------------------------------------------------------------===//
34 
35 namespace {
36 enum OpenMPDirectiveKindEx {
37   OMPD_cancellation = llvm::omp::Directive_enumSize + 1,
38   OMPD_data,
39   OMPD_declare,
40   OMPD_end,
41   OMPD_end_declare,
42   OMPD_enter,
43   OMPD_exit,
44   OMPD_point,
45   OMPD_reduction,
46   OMPD_target_enter,
47   OMPD_target_exit,
48   OMPD_update,
49   OMPD_distribute_parallel,
50   OMPD_teams_distribute_parallel,
51   OMPD_target_teams_distribute_parallel,
52   OMPD_mapper,
53   OMPD_variant,
54   OMPD_begin,
55   OMPD_begin_declare,
56 };
57 
58 // Helper to unify the enum class OpenMPDirectiveKind with its extension
59 // the OpenMPDirectiveKindEx enum which allows to use them together as if they
60 // are unsigned values.
61 struct OpenMPDirectiveKindExWrapper {
62   OpenMPDirectiveKindExWrapper(unsigned Value) : Value(Value) {}
63   OpenMPDirectiveKindExWrapper(OpenMPDirectiveKind DK) : Value(unsigned(DK)) {}
64   bool operator==(OpenMPDirectiveKindExWrapper V) const {
65     return Value == V.Value;
66   }
67   bool operator!=(OpenMPDirectiveKindExWrapper V) const {
68     return Value != V.Value;
69   }
70   bool operator==(OpenMPDirectiveKind V) const { return Value == unsigned(V); }
71   bool operator!=(OpenMPDirectiveKind V) const { return Value != unsigned(V); }
72   bool operator<(OpenMPDirectiveKind V) const { return Value < unsigned(V); }
73   operator unsigned() const { return Value; }
74   operator OpenMPDirectiveKind() const { return OpenMPDirectiveKind(Value); }
75   unsigned Value;
76 };
77 
78 class DeclDirectiveListParserHelper final {
79   SmallVector<Expr *, 4> Identifiers;
80   Parser *P;
81   OpenMPDirectiveKind Kind;
82 
83 public:
84   DeclDirectiveListParserHelper(Parser *P, OpenMPDirectiveKind Kind)
85       : P(P), Kind(Kind) {}
86   void operator()(CXXScopeSpec &SS, DeclarationNameInfo NameInfo) {
87     ExprResult Res = P->getActions().ActOnOpenMPIdExpression(
88         P->getCurScope(), SS, NameInfo, Kind);
89     if (Res.isUsable())
90       Identifiers.push_back(Res.get());
91   }
92   llvm::ArrayRef<Expr *> getIdentifiers() const { return Identifiers; }
93 };
94 } // namespace
95 
96 // Map token string to extended OMP token kind that are
97 // OpenMPDirectiveKind + OpenMPDirectiveKindEx.
98 static unsigned getOpenMPDirectiveKindEx(StringRef S) {
99   OpenMPDirectiveKindExWrapper DKind = getOpenMPDirectiveKind(S);
100   if (DKind != OMPD_unknown)
101     return DKind;
102 
103   return llvm::StringSwitch<OpenMPDirectiveKindExWrapper>(S)
104       .Case("cancellation", OMPD_cancellation)
105       .Case("data", OMPD_data)
106       .Case("declare", OMPD_declare)
107       .Case("end", OMPD_end)
108       .Case("enter", OMPD_enter)
109       .Case("exit", OMPD_exit)
110       .Case("point", OMPD_point)
111       .Case("reduction", OMPD_reduction)
112       .Case("update", OMPD_update)
113       .Case("mapper", OMPD_mapper)
114       .Case("variant", OMPD_variant)
115       .Case("begin", OMPD_begin)
116       .Default(OMPD_unknown);
117 }
118 
119 static OpenMPDirectiveKindExWrapper parseOpenMPDirectiveKind(Parser &P) {
120   // Array of foldings: F[i][0] F[i][1] ===> F[i][2].
121   // E.g.: OMPD_for OMPD_simd ===> OMPD_for_simd
122   // TODO: add other combined directives in topological order.
123   static const OpenMPDirectiveKindExWrapper F[][3] = {
124       {OMPD_begin, OMPD_declare, OMPD_begin_declare},
125       {OMPD_begin, OMPD_assumes, OMPD_begin_assumes},
126       {OMPD_end, OMPD_declare, OMPD_end_declare},
127       {OMPD_end, OMPD_assumes, OMPD_end_assumes},
128       {OMPD_cancellation, OMPD_point, OMPD_cancellation_point},
129       {OMPD_declare, OMPD_reduction, OMPD_declare_reduction},
130       {OMPD_declare, OMPD_mapper, OMPD_declare_mapper},
131       {OMPD_declare, OMPD_simd, OMPD_declare_simd},
132       {OMPD_declare, OMPD_target, OMPD_declare_target},
133       {OMPD_declare, OMPD_variant, OMPD_declare_variant},
134       {OMPD_begin_declare, OMPD_variant, OMPD_begin_declare_variant},
135       {OMPD_end_declare, OMPD_variant, OMPD_end_declare_variant},
136       {OMPD_distribute, OMPD_parallel, OMPD_distribute_parallel},
137       {OMPD_distribute_parallel, OMPD_for, OMPD_distribute_parallel_for},
138       {OMPD_distribute_parallel_for, OMPD_simd,
139        OMPD_distribute_parallel_for_simd},
140       {OMPD_distribute, OMPD_simd, OMPD_distribute_simd},
141       {OMPD_end_declare, OMPD_target, OMPD_end_declare_target},
142       {OMPD_target, OMPD_data, OMPD_target_data},
143       {OMPD_target, OMPD_enter, OMPD_target_enter},
144       {OMPD_target, OMPD_exit, OMPD_target_exit},
145       {OMPD_target, OMPD_update, OMPD_target_update},
146       {OMPD_target_enter, OMPD_data, OMPD_target_enter_data},
147       {OMPD_target_exit, OMPD_data, OMPD_target_exit_data},
148       {OMPD_for, OMPD_simd, OMPD_for_simd},
149       {OMPD_parallel, OMPD_for, OMPD_parallel_for},
150       {OMPD_parallel_for, OMPD_simd, OMPD_parallel_for_simd},
151       {OMPD_parallel, OMPD_sections, OMPD_parallel_sections},
152       {OMPD_taskloop, OMPD_simd, OMPD_taskloop_simd},
153       {OMPD_target, OMPD_parallel, OMPD_target_parallel},
154       {OMPD_target, OMPD_simd, OMPD_target_simd},
155       {OMPD_target_parallel, OMPD_for, OMPD_target_parallel_for},
156       {OMPD_target_parallel_for, OMPD_simd, OMPD_target_parallel_for_simd},
157       {OMPD_teams, OMPD_distribute, OMPD_teams_distribute},
158       {OMPD_teams_distribute, OMPD_simd, OMPD_teams_distribute_simd},
159       {OMPD_teams_distribute, OMPD_parallel, OMPD_teams_distribute_parallel},
160       {OMPD_teams_distribute_parallel, OMPD_for,
161        OMPD_teams_distribute_parallel_for},
162       {OMPD_teams_distribute_parallel_for, OMPD_simd,
163        OMPD_teams_distribute_parallel_for_simd},
164       {OMPD_target, OMPD_teams, OMPD_target_teams},
165       {OMPD_target_teams, OMPD_distribute, OMPD_target_teams_distribute},
166       {OMPD_target_teams_distribute, OMPD_parallel,
167        OMPD_target_teams_distribute_parallel},
168       {OMPD_target_teams_distribute, OMPD_simd,
169        OMPD_target_teams_distribute_simd},
170       {OMPD_target_teams_distribute_parallel, OMPD_for,
171        OMPD_target_teams_distribute_parallel_for},
172       {OMPD_target_teams_distribute_parallel_for, OMPD_simd,
173        OMPD_target_teams_distribute_parallel_for_simd},
174       {OMPD_master, OMPD_taskloop, OMPD_master_taskloop},
175       {OMPD_master_taskloop, OMPD_simd, OMPD_master_taskloop_simd},
176       {OMPD_parallel, OMPD_master, OMPD_parallel_master},
177       {OMPD_parallel_master, OMPD_taskloop, OMPD_parallel_master_taskloop},
178       {OMPD_parallel_master_taskloop, OMPD_simd,
179        OMPD_parallel_master_taskloop_simd}};
180   enum { CancellationPoint = 0, DeclareReduction = 1, TargetData = 2 };
181   Token Tok = P.getCurToken();
182   OpenMPDirectiveKindExWrapper DKind =
183       Tok.isAnnotation()
184           ? static_cast<unsigned>(OMPD_unknown)
185           : getOpenMPDirectiveKindEx(P.getPreprocessor().getSpelling(Tok));
186   if (DKind == OMPD_unknown)
187     return OMPD_unknown;
188 
189   for (unsigned I = 0; I < llvm::array_lengthof(F); ++I) {
190     if (DKind != F[I][0])
191       continue;
192 
193     Tok = P.getPreprocessor().LookAhead(0);
194     OpenMPDirectiveKindExWrapper SDKind =
195         Tok.isAnnotation()
196             ? static_cast<unsigned>(OMPD_unknown)
197             : getOpenMPDirectiveKindEx(P.getPreprocessor().getSpelling(Tok));
198     if (SDKind == OMPD_unknown)
199       continue;
200 
201     if (SDKind == F[I][1]) {
202       P.ConsumeToken();
203       DKind = F[I][2];
204     }
205   }
206   return unsigned(DKind) < llvm::omp::Directive_enumSize
207              ? static_cast<OpenMPDirectiveKind>(DKind)
208              : OMPD_unknown;
209 }
210 
211 static DeclarationName parseOpenMPReductionId(Parser &P) {
212   Token Tok = P.getCurToken();
213   Sema &Actions = P.getActions();
214   OverloadedOperatorKind OOK = OO_None;
215   // Allow to use 'operator' keyword for C++ operators
216   bool WithOperator = false;
217   if (Tok.is(tok::kw_operator)) {
218     P.ConsumeToken();
219     Tok = P.getCurToken();
220     WithOperator = true;
221   }
222   switch (Tok.getKind()) {
223   case tok::plus: // '+'
224     OOK = OO_Plus;
225     break;
226   case tok::minus: // '-'
227     OOK = OO_Minus;
228     break;
229   case tok::star: // '*'
230     OOK = OO_Star;
231     break;
232   case tok::amp: // '&'
233     OOK = OO_Amp;
234     break;
235   case tok::pipe: // '|'
236     OOK = OO_Pipe;
237     break;
238   case tok::caret: // '^'
239     OOK = OO_Caret;
240     break;
241   case tok::ampamp: // '&&'
242     OOK = OO_AmpAmp;
243     break;
244   case tok::pipepipe: // '||'
245     OOK = OO_PipePipe;
246     break;
247   case tok::identifier: // identifier
248     if (!WithOperator)
249       break;
250     LLVM_FALLTHROUGH;
251   default:
252     P.Diag(Tok.getLocation(), diag::err_omp_expected_reduction_identifier);
253     P.SkipUntil(tok::colon, tok::r_paren, tok::annot_pragma_openmp_end,
254                 Parser::StopBeforeMatch);
255     return DeclarationName();
256   }
257   P.ConsumeToken();
258   auto &DeclNames = Actions.getASTContext().DeclarationNames;
259   return OOK == OO_None ? DeclNames.getIdentifier(Tok.getIdentifierInfo())
260                         : DeclNames.getCXXOperatorName(OOK);
261 }
262 
263 /// Parse 'omp declare reduction' construct.
264 ///
265 ///       declare-reduction-directive:
266 ///        annot_pragma_openmp 'declare' 'reduction'
267 ///        '(' <reduction_id> ':' <type> {',' <type>} ':' <expression> ')'
268 ///        ['initializer' '(' ('omp_priv' '=' <expression>)|<function_call> ')']
269 ///        annot_pragma_openmp_end
270 /// <reduction_id> is either a base language identifier or one of the following
271 /// operators: '+', '-', '*', '&', '|', '^', '&&' and '||'.
272 ///
273 Parser::DeclGroupPtrTy
274 Parser::ParseOpenMPDeclareReductionDirective(AccessSpecifier AS) {
275   // Parse '('.
276   BalancedDelimiterTracker T(*this, tok::l_paren, tok::annot_pragma_openmp_end);
277   if (T.expectAndConsume(
278           diag::err_expected_lparen_after,
279           getOpenMPDirectiveName(OMPD_declare_reduction).data())) {
280     SkipUntil(tok::annot_pragma_openmp_end, StopBeforeMatch);
281     return DeclGroupPtrTy();
282   }
283 
284   DeclarationName Name = parseOpenMPReductionId(*this);
285   if (Name.isEmpty() && Tok.is(tok::annot_pragma_openmp_end))
286     return DeclGroupPtrTy();
287 
288   // Consume ':'.
289   bool IsCorrect = !ExpectAndConsume(tok::colon);
290 
291   if (!IsCorrect && Tok.is(tok::annot_pragma_openmp_end))
292     return DeclGroupPtrTy();
293 
294   IsCorrect = IsCorrect && !Name.isEmpty();
295 
296   if (Tok.is(tok::colon) || Tok.is(tok::annot_pragma_openmp_end)) {
297     Diag(Tok.getLocation(), diag::err_expected_type);
298     IsCorrect = false;
299   }
300 
301   if (!IsCorrect && Tok.is(tok::annot_pragma_openmp_end))
302     return DeclGroupPtrTy();
303 
304   SmallVector<std::pair<QualType, SourceLocation>, 8> ReductionTypes;
305   // Parse list of types until ':' token.
306   do {
307     ColonProtectionRAIIObject ColonRAII(*this);
308     SourceRange Range;
309     TypeResult TR = ParseTypeName(&Range, DeclaratorContext::Prototype, AS);
310     if (TR.isUsable()) {
311       QualType ReductionType =
312           Actions.ActOnOpenMPDeclareReductionType(Range.getBegin(), TR);
313       if (!ReductionType.isNull()) {
314         ReductionTypes.push_back(
315             std::make_pair(ReductionType, Range.getBegin()));
316       }
317     } else {
318       SkipUntil(tok::comma, tok::colon, tok::annot_pragma_openmp_end,
319                 StopBeforeMatch);
320     }
321 
322     if (Tok.is(tok::colon) || Tok.is(tok::annot_pragma_openmp_end))
323       break;
324 
325     // Consume ','.
326     if (ExpectAndConsume(tok::comma)) {
327       IsCorrect = false;
328       if (Tok.is(tok::annot_pragma_openmp_end)) {
329         Diag(Tok.getLocation(), diag::err_expected_type);
330         return DeclGroupPtrTy();
331       }
332     }
333   } while (Tok.isNot(tok::annot_pragma_openmp_end));
334 
335   if (ReductionTypes.empty()) {
336     SkipUntil(tok::annot_pragma_openmp_end, StopBeforeMatch);
337     return DeclGroupPtrTy();
338   }
339 
340   if (!IsCorrect && Tok.is(tok::annot_pragma_openmp_end))
341     return DeclGroupPtrTy();
342 
343   // Consume ':'.
344   if (ExpectAndConsume(tok::colon))
345     IsCorrect = false;
346 
347   if (Tok.is(tok::annot_pragma_openmp_end)) {
348     Diag(Tok.getLocation(), diag::err_expected_expression);
349     return DeclGroupPtrTy();
350   }
351 
352   DeclGroupPtrTy DRD = Actions.ActOnOpenMPDeclareReductionDirectiveStart(
353       getCurScope(), Actions.getCurLexicalContext(), Name, ReductionTypes, AS);
354 
355   // Parse <combiner> expression and then parse initializer if any for each
356   // correct type.
357   unsigned I = 0, E = ReductionTypes.size();
358   for (Decl *D : DRD.get()) {
359     TentativeParsingAction TPA(*this);
360     ParseScope OMPDRScope(this, Scope::FnScope | Scope::DeclScope |
361                                     Scope::CompoundStmtScope |
362                                     Scope::OpenMPDirectiveScope);
363     // Parse <combiner> expression.
364     Actions.ActOnOpenMPDeclareReductionCombinerStart(getCurScope(), D);
365     ExprResult CombinerResult = Actions.ActOnFinishFullExpr(
366         ParseExpression().get(), D->getLocation(), /*DiscardedValue*/ false);
367     Actions.ActOnOpenMPDeclareReductionCombinerEnd(D, CombinerResult.get());
368 
369     if (CombinerResult.isInvalid() && Tok.isNot(tok::r_paren) &&
370         Tok.isNot(tok::annot_pragma_openmp_end)) {
371       TPA.Commit();
372       IsCorrect = false;
373       break;
374     }
375     IsCorrect = !T.consumeClose() && IsCorrect && CombinerResult.isUsable();
376     ExprResult InitializerResult;
377     if (Tok.isNot(tok::annot_pragma_openmp_end)) {
378       // Parse <initializer> expression.
379       if (Tok.is(tok::identifier) &&
380           Tok.getIdentifierInfo()->isStr("initializer")) {
381         ConsumeToken();
382       } else {
383         Diag(Tok.getLocation(), diag::err_expected) << "'initializer'";
384         TPA.Commit();
385         IsCorrect = false;
386         break;
387       }
388       // Parse '('.
389       BalancedDelimiterTracker T(*this, tok::l_paren,
390                                  tok::annot_pragma_openmp_end);
391       IsCorrect =
392           !T.expectAndConsume(diag::err_expected_lparen_after, "initializer") &&
393           IsCorrect;
394       if (Tok.isNot(tok::annot_pragma_openmp_end)) {
395         ParseScope OMPDRScope(this, Scope::FnScope | Scope::DeclScope |
396                                         Scope::CompoundStmtScope |
397                                         Scope::OpenMPDirectiveScope);
398         // Parse expression.
399         VarDecl *OmpPrivParm =
400             Actions.ActOnOpenMPDeclareReductionInitializerStart(getCurScope(),
401                                                                 D);
402         // Check if initializer is omp_priv <init_expr> or something else.
403         if (Tok.is(tok::identifier) &&
404             Tok.getIdentifierInfo()->isStr("omp_priv")) {
405           ConsumeToken();
406           ParseOpenMPReductionInitializerForDecl(OmpPrivParm);
407         } else {
408           InitializerResult = Actions.ActOnFinishFullExpr(
409               ParseAssignmentExpression().get(), D->getLocation(),
410               /*DiscardedValue*/ false);
411         }
412         Actions.ActOnOpenMPDeclareReductionInitializerEnd(
413             D, InitializerResult.get(), OmpPrivParm);
414         if (InitializerResult.isInvalid() && Tok.isNot(tok::r_paren) &&
415             Tok.isNot(tok::annot_pragma_openmp_end)) {
416           TPA.Commit();
417           IsCorrect = false;
418           break;
419         }
420         IsCorrect =
421             !T.consumeClose() && IsCorrect && !InitializerResult.isInvalid();
422       }
423     }
424 
425     ++I;
426     // Revert parsing if not the last type, otherwise accept it, we're done with
427     // parsing.
428     if (I != E)
429       TPA.Revert();
430     else
431       TPA.Commit();
432   }
433   return Actions.ActOnOpenMPDeclareReductionDirectiveEnd(getCurScope(), DRD,
434                                                          IsCorrect);
435 }
436 
437 void Parser::ParseOpenMPReductionInitializerForDecl(VarDecl *OmpPrivParm) {
438   // Parse declarator '=' initializer.
439   // If a '==' or '+=' is found, suggest a fixit to '='.
440   if (isTokenEqualOrEqualTypo()) {
441     ConsumeToken();
442 
443     if (Tok.is(tok::code_completion)) {
444       cutOffParsing();
445       Actions.CodeCompleteInitializer(getCurScope(), OmpPrivParm);
446       Actions.FinalizeDeclaration(OmpPrivParm);
447       return;
448     }
449 
450     PreferredType.enterVariableInit(Tok.getLocation(), OmpPrivParm);
451     ExprResult Init = ParseInitializer();
452 
453     if (Init.isInvalid()) {
454       SkipUntil(tok::r_paren, tok::annot_pragma_openmp_end, StopBeforeMatch);
455       Actions.ActOnInitializerError(OmpPrivParm);
456     } else {
457       Actions.AddInitializerToDecl(OmpPrivParm, Init.get(),
458                                    /*DirectInit=*/false);
459     }
460   } else if (Tok.is(tok::l_paren)) {
461     // Parse C++ direct initializer: '(' expression-list ')'
462     BalancedDelimiterTracker T(*this, tok::l_paren);
463     T.consumeOpen();
464 
465     ExprVector Exprs;
466     CommaLocsTy CommaLocs;
467 
468     SourceLocation LParLoc = T.getOpenLocation();
469     auto RunSignatureHelp = [this, OmpPrivParm, LParLoc, &Exprs]() {
470       QualType PreferredType = Actions.ProduceConstructorSignatureHelp(
471           getCurScope(), OmpPrivParm->getType()->getCanonicalTypeInternal(),
472           OmpPrivParm->getLocation(), Exprs, LParLoc);
473       CalledSignatureHelp = true;
474       return PreferredType;
475     };
476     if (ParseExpressionList(Exprs, CommaLocs, [&] {
477           PreferredType.enterFunctionArgument(Tok.getLocation(),
478                                               RunSignatureHelp);
479         })) {
480       if (PP.isCodeCompletionReached() && !CalledSignatureHelp)
481         RunSignatureHelp();
482       Actions.ActOnInitializerError(OmpPrivParm);
483       SkipUntil(tok::r_paren, tok::annot_pragma_openmp_end, StopBeforeMatch);
484     } else {
485       // Match the ')'.
486       SourceLocation RLoc = Tok.getLocation();
487       if (!T.consumeClose())
488         RLoc = T.getCloseLocation();
489 
490       assert(!Exprs.empty() && Exprs.size() - 1 == CommaLocs.size() &&
491              "Unexpected number of commas!");
492 
493       ExprResult Initializer =
494           Actions.ActOnParenListExpr(T.getOpenLocation(), RLoc, Exprs);
495       Actions.AddInitializerToDecl(OmpPrivParm, Initializer.get(),
496                                    /*DirectInit=*/true);
497     }
498   } else if (getLangOpts().CPlusPlus11 && Tok.is(tok::l_brace)) {
499     // Parse C++0x braced-init-list.
500     Diag(Tok, diag::warn_cxx98_compat_generalized_initializer_lists);
501 
502     ExprResult Init(ParseBraceInitializer());
503 
504     if (Init.isInvalid()) {
505       Actions.ActOnInitializerError(OmpPrivParm);
506     } else {
507       Actions.AddInitializerToDecl(OmpPrivParm, Init.get(),
508                                    /*DirectInit=*/true);
509     }
510   } else {
511     Actions.ActOnUninitializedDecl(OmpPrivParm);
512   }
513 }
514 
515 /// Parses 'omp declare mapper' directive.
516 ///
517 ///       declare-mapper-directive:
518 ///         annot_pragma_openmp 'declare' 'mapper' '(' [<mapper-identifier> ':']
519 ///         <type> <var> ')' [<clause>[[,] <clause>] ... ]
520 ///         annot_pragma_openmp_end
521 /// <mapper-identifier> and <var> are base language identifiers.
522 ///
523 Parser::DeclGroupPtrTy
524 Parser::ParseOpenMPDeclareMapperDirective(AccessSpecifier AS) {
525   bool IsCorrect = true;
526   // Parse '('
527   BalancedDelimiterTracker T(*this, tok::l_paren, tok::annot_pragma_openmp_end);
528   if (T.expectAndConsume(diag::err_expected_lparen_after,
529                          getOpenMPDirectiveName(OMPD_declare_mapper).data())) {
530     SkipUntil(tok::annot_pragma_openmp_end, StopBeforeMatch);
531     return DeclGroupPtrTy();
532   }
533 
534   // Parse <mapper-identifier>
535   auto &DeclNames = Actions.getASTContext().DeclarationNames;
536   DeclarationName MapperId;
537   if (PP.LookAhead(0).is(tok::colon)) {
538     if (Tok.isNot(tok::identifier) && Tok.isNot(tok::kw_default)) {
539       Diag(Tok.getLocation(), diag::err_omp_mapper_illegal_identifier);
540       IsCorrect = false;
541     } else {
542       MapperId = DeclNames.getIdentifier(Tok.getIdentifierInfo());
543     }
544     ConsumeToken();
545     // Consume ':'.
546     ExpectAndConsume(tok::colon);
547   } else {
548     // If no mapper identifier is provided, its name is "default" by default
549     MapperId =
550         DeclNames.getIdentifier(&Actions.getASTContext().Idents.get("default"));
551   }
552 
553   if (!IsCorrect && Tok.is(tok::annot_pragma_openmp_end))
554     return DeclGroupPtrTy();
555 
556   // Parse <type> <var>
557   DeclarationName VName;
558   QualType MapperType;
559   SourceRange Range;
560   TypeResult ParsedType = parseOpenMPDeclareMapperVarDecl(Range, VName, AS);
561   if (ParsedType.isUsable())
562     MapperType =
563         Actions.ActOnOpenMPDeclareMapperType(Range.getBegin(), ParsedType);
564   if (MapperType.isNull())
565     IsCorrect = false;
566   if (!IsCorrect) {
567     SkipUntil(tok::annot_pragma_openmp_end, Parser::StopBeforeMatch);
568     return DeclGroupPtrTy();
569   }
570 
571   // Consume ')'.
572   IsCorrect &= !T.consumeClose();
573   if (!IsCorrect) {
574     SkipUntil(tok::annot_pragma_openmp_end, Parser::StopBeforeMatch);
575     return DeclGroupPtrTy();
576   }
577 
578   // Enter scope.
579   DeclarationNameInfo DirName;
580   SourceLocation Loc = Tok.getLocation();
581   unsigned ScopeFlags = Scope::FnScope | Scope::DeclScope |
582                         Scope::CompoundStmtScope | Scope::OpenMPDirectiveScope;
583   ParseScope OMPDirectiveScope(this, ScopeFlags);
584   Actions.StartOpenMPDSABlock(OMPD_declare_mapper, DirName, getCurScope(), Loc);
585 
586   // Add the mapper variable declaration.
587   ExprResult MapperVarRef = Actions.ActOnOpenMPDeclareMapperDirectiveVarDecl(
588       getCurScope(), MapperType, Range.getBegin(), VName);
589 
590   // Parse map clauses.
591   SmallVector<OMPClause *, 6> Clauses;
592   while (Tok.isNot(tok::annot_pragma_openmp_end)) {
593     OpenMPClauseKind CKind = Tok.isAnnotation()
594                                  ? OMPC_unknown
595                                  : getOpenMPClauseKind(PP.getSpelling(Tok));
596     Actions.StartOpenMPClause(CKind);
597     OMPClause *Clause =
598         ParseOpenMPClause(OMPD_declare_mapper, CKind, Clauses.empty());
599     if (Clause)
600       Clauses.push_back(Clause);
601     else
602       IsCorrect = false;
603     // Skip ',' if any.
604     if (Tok.is(tok::comma))
605       ConsumeToken();
606     Actions.EndOpenMPClause();
607   }
608   if (Clauses.empty()) {
609     Diag(Tok, diag::err_omp_expected_clause)
610         << getOpenMPDirectiveName(OMPD_declare_mapper);
611     IsCorrect = false;
612   }
613 
614   // Exit scope.
615   Actions.EndOpenMPDSABlock(nullptr);
616   OMPDirectiveScope.Exit();
617   DeclGroupPtrTy DG = Actions.ActOnOpenMPDeclareMapperDirective(
618       getCurScope(), Actions.getCurLexicalContext(), MapperId, MapperType,
619       Range.getBegin(), VName, AS, MapperVarRef.get(), Clauses);
620   if (!IsCorrect)
621     return DeclGroupPtrTy();
622 
623   return DG;
624 }
625 
626 TypeResult Parser::parseOpenMPDeclareMapperVarDecl(SourceRange &Range,
627                                                    DeclarationName &Name,
628                                                    AccessSpecifier AS) {
629   // Parse the common declaration-specifiers piece.
630   Parser::DeclSpecContext DSC = Parser::DeclSpecContext::DSC_type_specifier;
631   DeclSpec DS(AttrFactory);
632   ParseSpecifierQualifierList(DS, AS, DSC);
633 
634   // Parse the declarator.
635   DeclaratorContext Context = DeclaratorContext::Prototype;
636   Declarator DeclaratorInfo(DS, Context);
637   ParseDeclarator(DeclaratorInfo);
638   Range = DeclaratorInfo.getSourceRange();
639   if (DeclaratorInfo.getIdentifier() == nullptr) {
640     Diag(Tok.getLocation(), diag::err_omp_mapper_expected_declarator);
641     return true;
642   }
643   Name = Actions.GetNameForDeclarator(DeclaratorInfo).getName();
644 
645   return Actions.ActOnOpenMPDeclareMapperVarDecl(getCurScope(), DeclaratorInfo);
646 }
647 
648 namespace {
649 /// RAII that recreates function context for correct parsing of clauses of
650 /// 'declare simd' construct.
651 /// OpenMP, 2.8.2 declare simd Construct
652 /// The expressions appearing in the clauses of this directive are evaluated in
653 /// the scope of the arguments of the function declaration or definition.
654 class FNContextRAII final {
655   Parser &P;
656   Sema::CXXThisScopeRAII *ThisScope;
657   Parser::MultiParseScope Scopes;
658   bool HasFunScope = false;
659   FNContextRAII() = delete;
660   FNContextRAII(const FNContextRAII &) = delete;
661   FNContextRAII &operator=(const FNContextRAII &) = delete;
662 
663 public:
664   FNContextRAII(Parser &P, Parser::DeclGroupPtrTy Ptr) : P(P), Scopes(P) {
665     Decl *D = *Ptr.get().begin();
666     NamedDecl *ND = dyn_cast<NamedDecl>(D);
667     RecordDecl *RD = dyn_cast_or_null<RecordDecl>(D->getDeclContext());
668     Sema &Actions = P.getActions();
669 
670     // Allow 'this' within late-parsed attributes.
671     ThisScope = new Sema::CXXThisScopeRAII(Actions, RD, Qualifiers(),
672                                            ND && ND->isCXXInstanceMember());
673 
674     // If the Decl is templatized, add template parameters to scope.
675     // FIXME: Track CurTemplateDepth?
676     P.ReenterTemplateScopes(Scopes, D);
677 
678     // If the Decl is on a function, add function parameters to the scope.
679     if (D->isFunctionOrFunctionTemplate()) {
680       HasFunScope = true;
681       Scopes.Enter(Scope::FnScope | Scope::DeclScope |
682                    Scope::CompoundStmtScope);
683       Actions.ActOnReenterFunctionContext(Actions.getCurScope(), D);
684     }
685   }
686   ~FNContextRAII() {
687     if (HasFunScope)
688       P.getActions().ActOnExitFunctionContext();
689     delete ThisScope;
690   }
691 };
692 } // namespace
693 
694 /// Parses clauses for 'declare simd' directive.
695 ///    clause:
696 ///      'inbranch' | 'notinbranch'
697 ///      'simdlen' '(' <expr> ')'
698 ///      { 'uniform' '(' <argument_list> ')' }
699 ///      { 'aligned '(' <argument_list> [ ':' <alignment> ] ')' }
700 ///      { 'linear '(' <argument_list> [ ':' <step> ] ')' }
701 static bool parseDeclareSimdClauses(
702     Parser &P, OMPDeclareSimdDeclAttr::BranchStateTy &BS, ExprResult &SimdLen,
703     SmallVectorImpl<Expr *> &Uniforms, SmallVectorImpl<Expr *> &Aligneds,
704     SmallVectorImpl<Expr *> &Alignments, SmallVectorImpl<Expr *> &Linears,
705     SmallVectorImpl<unsigned> &LinModifiers, SmallVectorImpl<Expr *> &Steps) {
706   SourceRange BSRange;
707   const Token &Tok = P.getCurToken();
708   bool IsError = false;
709   while (Tok.isNot(tok::annot_pragma_openmp_end)) {
710     if (Tok.isNot(tok::identifier))
711       break;
712     OMPDeclareSimdDeclAttr::BranchStateTy Out;
713     IdentifierInfo *II = Tok.getIdentifierInfo();
714     StringRef ClauseName = II->getName();
715     // Parse 'inranch|notinbranch' clauses.
716     if (OMPDeclareSimdDeclAttr::ConvertStrToBranchStateTy(ClauseName, Out)) {
717       if (BS != OMPDeclareSimdDeclAttr::BS_Undefined && BS != Out) {
718         P.Diag(Tok, diag::err_omp_declare_simd_inbranch_notinbranch)
719             << ClauseName
720             << OMPDeclareSimdDeclAttr::ConvertBranchStateTyToStr(BS) << BSRange;
721         IsError = true;
722       }
723       BS = Out;
724       BSRange = SourceRange(Tok.getLocation(), Tok.getEndLoc());
725       P.ConsumeToken();
726     } else if (ClauseName.equals("simdlen")) {
727       if (SimdLen.isUsable()) {
728         P.Diag(Tok, diag::err_omp_more_one_clause)
729             << getOpenMPDirectiveName(OMPD_declare_simd) << ClauseName << 0;
730         IsError = true;
731       }
732       P.ConsumeToken();
733       SourceLocation RLoc;
734       SimdLen = P.ParseOpenMPParensExpr(ClauseName, RLoc);
735       if (SimdLen.isInvalid())
736         IsError = true;
737     } else {
738       OpenMPClauseKind CKind = getOpenMPClauseKind(ClauseName);
739       if (CKind == OMPC_uniform || CKind == OMPC_aligned ||
740           CKind == OMPC_linear) {
741         Parser::OpenMPVarListDataTy Data;
742         SmallVectorImpl<Expr *> *Vars = &Uniforms;
743         if (CKind == OMPC_aligned) {
744           Vars = &Aligneds;
745         } else if (CKind == OMPC_linear) {
746           Data.ExtraModifier = OMPC_LINEAR_val;
747           Vars = &Linears;
748         }
749 
750         P.ConsumeToken();
751         if (P.ParseOpenMPVarList(OMPD_declare_simd,
752                                  getOpenMPClauseKind(ClauseName), *Vars, Data))
753           IsError = true;
754         if (CKind == OMPC_aligned) {
755           Alignments.append(Aligneds.size() - Alignments.size(),
756                             Data.DepModOrTailExpr);
757         } else if (CKind == OMPC_linear) {
758           assert(0 <= Data.ExtraModifier &&
759                  Data.ExtraModifier <= OMPC_LINEAR_unknown &&
760                  "Unexpected linear modifier.");
761           if (P.getActions().CheckOpenMPLinearModifier(
762                   static_cast<OpenMPLinearClauseKind>(Data.ExtraModifier),
763                   Data.ExtraModifierLoc))
764             Data.ExtraModifier = OMPC_LINEAR_val;
765           LinModifiers.append(Linears.size() - LinModifiers.size(),
766                               Data.ExtraModifier);
767           Steps.append(Linears.size() - Steps.size(), Data.DepModOrTailExpr);
768         }
769       } else
770         // TODO: add parsing of other clauses.
771         break;
772     }
773     // Skip ',' if any.
774     if (Tok.is(tok::comma))
775       P.ConsumeToken();
776   }
777   return IsError;
778 }
779 
780 /// Parse clauses for '#pragma omp declare simd'.
781 Parser::DeclGroupPtrTy
782 Parser::ParseOMPDeclareSimdClauses(Parser::DeclGroupPtrTy Ptr,
783                                    CachedTokens &Toks, SourceLocation Loc) {
784   PP.EnterToken(Tok, /*IsReinject*/ true);
785   PP.EnterTokenStream(Toks, /*DisableMacroExpansion=*/true,
786                       /*IsReinject*/ true);
787   // Consume the previously pushed token.
788   ConsumeAnyToken(/*ConsumeCodeCompletionTok=*/true);
789   ConsumeAnyToken(/*ConsumeCodeCompletionTok=*/true);
790 
791   FNContextRAII FnContext(*this, Ptr);
792   OMPDeclareSimdDeclAttr::BranchStateTy BS =
793       OMPDeclareSimdDeclAttr::BS_Undefined;
794   ExprResult Simdlen;
795   SmallVector<Expr *, 4> Uniforms;
796   SmallVector<Expr *, 4> Aligneds;
797   SmallVector<Expr *, 4> Alignments;
798   SmallVector<Expr *, 4> Linears;
799   SmallVector<unsigned, 4> LinModifiers;
800   SmallVector<Expr *, 4> Steps;
801   bool IsError =
802       parseDeclareSimdClauses(*this, BS, Simdlen, Uniforms, Aligneds,
803                               Alignments, Linears, LinModifiers, Steps);
804   skipUntilPragmaOpenMPEnd(OMPD_declare_simd);
805   // Skip the last annot_pragma_openmp_end.
806   SourceLocation EndLoc = ConsumeAnnotationToken();
807   if (IsError)
808     return Ptr;
809   return Actions.ActOnOpenMPDeclareSimdDirective(
810       Ptr, BS, Simdlen.get(), Uniforms, Aligneds, Alignments, Linears,
811       LinModifiers, Steps, SourceRange(Loc, EndLoc));
812 }
813 
814 namespace {
815 /// Constant used in the diagnostics to distinguish the levels in an OpenMP
816 /// contexts: selector-set={selector(trait, ...), ...}, ....
817 enum OMPContextLvl {
818   CONTEXT_SELECTOR_SET_LVL = 0,
819   CONTEXT_SELECTOR_LVL = 1,
820   CONTEXT_TRAIT_LVL = 2,
821 };
822 
823 static StringRef stringLiteralParser(Parser &P) {
824   ExprResult Res = P.ParseStringLiteralExpression(true);
825   return Res.isUsable() ? Res.getAs<StringLiteral>()->getString() : "";
826 }
827 
828 static StringRef getNameFromIdOrString(Parser &P, Token &Tok,
829                                        OMPContextLvl Lvl) {
830   if (Tok.is(tok::identifier)) {
831     llvm::SmallString<16> Buffer;
832     StringRef Name = P.getPreprocessor().getSpelling(Tok, Buffer);
833     (void)P.ConsumeToken();
834     return Name;
835   }
836 
837   if (tok::isStringLiteral(Tok.getKind()))
838     return stringLiteralParser(P);
839 
840   P.Diag(Tok.getLocation(),
841          diag::warn_omp_declare_variant_string_literal_or_identifier)
842       << Lvl;
843   return "";
844 }
845 
846 static bool checkForDuplicates(Parser &P, StringRef Name,
847                                SourceLocation NameLoc,
848                                llvm::StringMap<SourceLocation> &Seen,
849                                OMPContextLvl Lvl) {
850   auto Res = Seen.try_emplace(Name, NameLoc);
851   if (Res.second)
852     return false;
853 
854   // Each trait-set-selector-name, trait-selector-name and trait-name can
855   // only be specified once.
856   P.Diag(NameLoc, diag::warn_omp_declare_variant_ctx_mutiple_use)
857       << Lvl << Name;
858   P.Diag(Res.first->getValue(), diag::note_omp_declare_variant_ctx_used_here)
859       << Lvl << Name;
860   return true;
861 }
862 } // namespace
863 
864 void Parser::parseOMPTraitPropertyKind(OMPTraitProperty &TIProperty,
865                                        llvm::omp::TraitSet Set,
866                                        llvm::omp::TraitSelector Selector,
867                                        llvm::StringMap<SourceLocation> &Seen) {
868   TIProperty.Kind = TraitProperty::invalid;
869 
870   SourceLocation NameLoc = Tok.getLocation();
871   StringRef Name = getNameFromIdOrString(*this, Tok, CONTEXT_TRAIT_LVL);
872   if (Name.empty()) {
873     Diag(Tok.getLocation(), diag::note_omp_declare_variant_ctx_options)
874         << CONTEXT_TRAIT_LVL << listOpenMPContextTraitProperties(Set, Selector);
875     return;
876   }
877 
878   TIProperty.RawString = Name;
879   TIProperty.Kind = getOpenMPContextTraitPropertyKind(Set, Selector, Name);
880   if (TIProperty.Kind != TraitProperty::invalid) {
881     if (checkForDuplicates(*this, Name, NameLoc, Seen, CONTEXT_TRAIT_LVL))
882       TIProperty.Kind = TraitProperty::invalid;
883     return;
884   }
885 
886   // It follows diagnosis and helping notes.
887   // FIXME: We should move the diagnosis string generation into libFrontend.
888   Diag(NameLoc, diag::warn_omp_declare_variant_ctx_not_a_property)
889       << Name << getOpenMPContextTraitSelectorName(Selector)
890       << getOpenMPContextTraitSetName(Set);
891 
892   TraitSet SetForName = getOpenMPContextTraitSetKind(Name);
893   if (SetForName != TraitSet::invalid) {
894     Diag(NameLoc, diag::note_omp_declare_variant_ctx_is_a)
895         << Name << CONTEXT_SELECTOR_SET_LVL << CONTEXT_TRAIT_LVL;
896     Diag(NameLoc, diag::note_omp_declare_variant_ctx_try)
897         << Name << "<selector-name>"
898         << "(<property-name>)";
899     return;
900   }
901   TraitSelector SelectorForName = getOpenMPContextTraitSelectorKind(Name);
902   if (SelectorForName != TraitSelector::invalid) {
903     Diag(NameLoc, diag::note_omp_declare_variant_ctx_is_a)
904         << Name << CONTEXT_SELECTOR_LVL << CONTEXT_TRAIT_LVL;
905     bool AllowsTraitScore = false;
906     bool RequiresProperty = false;
907     isValidTraitSelectorForTraitSet(
908         SelectorForName, getOpenMPContextTraitSetForSelector(SelectorForName),
909         AllowsTraitScore, RequiresProperty);
910     Diag(NameLoc, diag::note_omp_declare_variant_ctx_try)
911         << getOpenMPContextTraitSetName(
912                getOpenMPContextTraitSetForSelector(SelectorForName))
913         << Name << (RequiresProperty ? "(<property-name>)" : "");
914     return;
915   }
916   for (const auto &PotentialSet :
917        {TraitSet::construct, TraitSet::user, TraitSet::implementation,
918         TraitSet::device}) {
919     TraitProperty PropertyForName =
920         getOpenMPContextTraitPropertyKind(PotentialSet, Selector, Name);
921     if (PropertyForName == TraitProperty::invalid)
922       continue;
923     Diag(NameLoc, diag::note_omp_declare_variant_ctx_try)
924         << getOpenMPContextTraitSetName(
925                getOpenMPContextTraitSetForProperty(PropertyForName))
926         << getOpenMPContextTraitSelectorName(
927                getOpenMPContextTraitSelectorForProperty(PropertyForName))
928         << ("(" + Name + ")").str();
929     return;
930   }
931   Diag(NameLoc, diag::note_omp_declare_variant_ctx_options)
932       << CONTEXT_TRAIT_LVL << listOpenMPContextTraitProperties(Set, Selector);
933 }
934 
935 static bool checkExtensionProperty(Parser &P, SourceLocation Loc,
936                                    OMPTraitProperty &TIProperty,
937                                    OMPTraitSelector &TISelector,
938                                    llvm::StringMap<SourceLocation> &Seen) {
939   assert(TISelector.Kind ==
940              llvm::omp::TraitSelector::implementation_extension &&
941          "Only for extension properties, e.g., "
942          "`implementation={extension(PROPERTY)}`");
943   if (TIProperty.Kind == TraitProperty::invalid)
944     return false;
945 
946   if (TIProperty.Kind ==
947       TraitProperty::implementation_extension_disable_implicit_base)
948     return true;
949 
950   if (TIProperty.Kind ==
951       TraitProperty::implementation_extension_allow_templates)
952     return true;
953 
954   auto IsMatchExtension = [](OMPTraitProperty &TP) {
955     return (TP.Kind ==
956                 llvm::omp::TraitProperty::implementation_extension_match_all ||
957             TP.Kind ==
958                 llvm::omp::TraitProperty::implementation_extension_match_any ||
959             TP.Kind ==
960                 llvm::omp::TraitProperty::implementation_extension_match_none);
961   };
962 
963   if (IsMatchExtension(TIProperty)) {
964     for (OMPTraitProperty &SeenProp : TISelector.Properties)
965       if (IsMatchExtension(SeenProp)) {
966         P.Diag(Loc, diag::err_omp_variant_ctx_second_match_extension);
967         StringRef SeenName = llvm::omp::getOpenMPContextTraitPropertyName(
968             SeenProp.Kind, SeenProp.RawString);
969         SourceLocation SeenLoc = Seen[SeenName];
970         P.Diag(SeenLoc, diag::note_omp_declare_variant_ctx_used_here)
971             << CONTEXT_TRAIT_LVL << SeenName;
972         return false;
973       }
974     return true;
975   }
976 
977   llvm_unreachable("Unknown extension property!");
978 }
979 
980 void Parser::parseOMPContextProperty(OMPTraitSelector &TISelector,
981                                      llvm::omp::TraitSet Set,
982                                      llvm::StringMap<SourceLocation> &Seen) {
983   assert(TISelector.Kind != TraitSelector::user_condition &&
984          "User conditions are special properties not handled here!");
985 
986   SourceLocation PropertyLoc = Tok.getLocation();
987   OMPTraitProperty TIProperty;
988   parseOMPTraitPropertyKind(TIProperty, Set, TISelector.Kind, Seen);
989 
990   if (TISelector.Kind == llvm::omp::TraitSelector::implementation_extension)
991     if (!checkExtensionProperty(*this, Tok.getLocation(), TIProperty,
992                                 TISelector, Seen))
993       TIProperty.Kind = TraitProperty::invalid;
994 
995   // If we have an invalid property here we already issued a warning.
996   if (TIProperty.Kind == TraitProperty::invalid) {
997     if (PropertyLoc != Tok.getLocation())
998       Diag(Tok.getLocation(), diag::note_omp_declare_variant_ctx_continue_here)
999           << CONTEXT_TRAIT_LVL;
1000     return;
1001   }
1002 
1003   if (isValidTraitPropertyForTraitSetAndSelector(TIProperty.Kind,
1004                                                  TISelector.Kind, Set)) {
1005 
1006     // If we make it here the property, selector, set, score, condition, ... are
1007     // all valid (or have been corrected). Thus we can record the property.
1008     TISelector.Properties.push_back(TIProperty);
1009     return;
1010   }
1011 
1012   Diag(PropertyLoc, diag::warn_omp_ctx_incompatible_property_for_selector)
1013       << getOpenMPContextTraitPropertyName(TIProperty.Kind,
1014                                            TIProperty.RawString)
1015       << getOpenMPContextTraitSelectorName(TISelector.Kind)
1016       << getOpenMPContextTraitSetName(Set);
1017   Diag(PropertyLoc, diag::note_omp_ctx_compatible_set_and_selector_for_property)
1018       << getOpenMPContextTraitPropertyName(TIProperty.Kind,
1019                                            TIProperty.RawString)
1020       << getOpenMPContextTraitSelectorName(
1021              getOpenMPContextTraitSelectorForProperty(TIProperty.Kind))
1022       << getOpenMPContextTraitSetName(
1023              getOpenMPContextTraitSetForProperty(TIProperty.Kind));
1024   Diag(Tok.getLocation(), diag::note_omp_declare_variant_ctx_continue_here)
1025       << CONTEXT_TRAIT_LVL;
1026 }
1027 
1028 void Parser::parseOMPTraitSelectorKind(OMPTraitSelector &TISelector,
1029                                        llvm::omp::TraitSet Set,
1030                                        llvm::StringMap<SourceLocation> &Seen) {
1031   TISelector.Kind = TraitSelector::invalid;
1032 
1033   SourceLocation NameLoc = Tok.getLocation();
1034   StringRef Name = getNameFromIdOrString(*this, Tok, CONTEXT_SELECTOR_LVL);
1035   if (Name.empty()) {
1036     Diag(Tok.getLocation(), diag::note_omp_declare_variant_ctx_options)
1037         << CONTEXT_SELECTOR_LVL << listOpenMPContextTraitSelectors(Set);
1038     return;
1039   }
1040 
1041   TISelector.Kind = getOpenMPContextTraitSelectorKind(Name);
1042   if (TISelector.Kind != TraitSelector::invalid) {
1043     if (checkForDuplicates(*this, Name, NameLoc, Seen, CONTEXT_SELECTOR_LVL))
1044       TISelector.Kind = TraitSelector::invalid;
1045     return;
1046   }
1047 
1048   // It follows diagnosis and helping notes.
1049   Diag(NameLoc, diag::warn_omp_declare_variant_ctx_not_a_selector)
1050       << Name << getOpenMPContextTraitSetName(Set);
1051 
1052   TraitSet SetForName = getOpenMPContextTraitSetKind(Name);
1053   if (SetForName != TraitSet::invalid) {
1054     Diag(NameLoc, diag::note_omp_declare_variant_ctx_is_a)
1055         << Name << CONTEXT_SELECTOR_SET_LVL << CONTEXT_SELECTOR_LVL;
1056     Diag(NameLoc, diag::note_omp_declare_variant_ctx_try)
1057         << Name << "<selector-name>"
1058         << "<property-name>";
1059     return;
1060   }
1061   for (const auto &PotentialSet :
1062        {TraitSet::construct, TraitSet::user, TraitSet::implementation,
1063         TraitSet::device}) {
1064     TraitProperty PropertyForName = getOpenMPContextTraitPropertyKind(
1065         PotentialSet, TraitSelector::invalid, Name);
1066     if (PropertyForName == TraitProperty::invalid)
1067       continue;
1068     Diag(NameLoc, diag::note_omp_declare_variant_ctx_is_a)
1069         << Name << CONTEXT_TRAIT_LVL << CONTEXT_SELECTOR_LVL;
1070     Diag(NameLoc, diag::note_omp_declare_variant_ctx_try)
1071         << getOpenMPContextTraitSetName(
1072                getOpenMPContextTraitSetForProperty(PropertyForName))
1073         << getOpenMPContextTraitSelectorName(
1074                getOpenMPContextTraitSelectorForProperty(PropertyForName))
1075         << ("(" + Name + ")").str();
1076     return;
1077   }
1078   Diag(NameLoc, diag::note_omp_declare_variant_ctx_options)
1079       << CONTEXT_SELECTOR_LVL << listOpenMPContextTraitSelectors(Set);
1080 }
1081 
1082 /// Parse optional 'score' '(' <expr> ')' ':'.
1083 static ExprResult parseContextScore(Parser &P) {
1084   ExprResult ScoreExpr;
1085   llvm::SmallString<16> Buffer;
1086   StringRef SelectorName =
1087       P.getPreprocessor().getSpelling(P.getCurToken(), Buffer);
1088   if (!SelectorName.equals("score"))
1089     return ScoreExpr;
1090   (void)P.ConsumeToken();
1091   SourceLocation RLoc;
1092   ScoreExpr = P.ParseOpenMPParensExpr(SelectorName, RLoc);
1093   // Parse ':'
1094   if (P.getCurToken().is(tok::colon))
1095     (void)P.ConsumeAnyToken();
1096   else
1097     P.Diag(P.getCurToken(), diag::warn_omp_declare_variant_expected)
1098         << "':'"
1099         << "score expression";
1100   return ScoreExpr;
1101 }
1102 
1103 /// Parses an OpenMP context selector.
1104 ///
1105 /// <trait-selector-name> ['('[<trait-score>] <trait-property> [, <t-p>]* ')']
1106 void Parser::parseOMPContextSelector(
1107     OMPTraitSelector &TISelector, llvm::omp::TraitSet Set,
1108     llvm::StringMap<SourceLocation> &SeenSelectors) {
1109   unsigned short OuterPC = ParenCount;
1110 
1111   // If anything went wrong we issue an error or warning and then skip the rest
1112   // of the selector. However, commas are ambiguous so we look for the nesting
1113   // of parentheses here as well.
1114   auto FinishSelector = [OuterPC, this]() -> void {
1115     bool Done = false;
1116     while (!Done) {
1117       while (!SkipUntil({tok::r_brace, tok::r_paren, tok::comma,
1118                          tok::annot_pragma_openmp_end},
1119                         StopBeforeMatch))
1120         ;
1121       if (Tok.is(tok::r_paren) && OuterPC > ParenCount)
1122         (void)ConsumeParen();
1123       if (OuterPC <= ParenCount) {
1124         Done = true;
1125         break;
1126       }
1127       if (!Tok.is(tok::comma) && !Tok.is(tok::r_paren)) {
1128         Done = true;
1129         break;
1130       }
1131       (void)ConsumeAnyToken();
1132     }
1133     Diag(Tok.getLocation(), diag::note_omp_declare_variant_ctx_continue_here)
1134         << CONTEXT_SELECTOR_LVL;
1135   };
1136 
1137   SourceLocation SelectorLoc = Tok.getLocation();
1138   parseOMPTraitSelectorKind(TISelector, Set, SeenSelectors);
1139   if (TISelector.Kind == TraitSelector::invalid)
1140     return FinishSelector();
1141 
1142   bool AllowsTraitScore = false;
1143   bool RequiresProperty = false;
1144   if (!isValidTraitSelectorForTraitSet(TISelector.Kind, Set, AllowsTraitScore,
1145                                        RequiresProperty)) {
1146     Diag(SelectorLoc, diag::warn_omp_ctx_incompatible_selector_for_set)
1147         << getOpenMPContextTraitSelectorName(TISelector.Kind)
1148         << getOpenMPContextTraitSetName(Set);
1149     Diag(SelectorLoc, diag::note_omp_ctx_compatible_set_for_selector)
1150         << getOpenMPContextTraitSelectorName(TISelector.Kind)
1151         << getOpenMPContextTraitSetName(
1152                getOpenMPContextTraitSetForSelector(TISelector.Kind))
1153         << RequiresProperty;
1154     return FinishSelector();
1155   }
1156 
1157   if (!RequiresProperty) {
1158     TISelector.Properties.push_back(
1159         {getOpenMPContextTraitPropertyForSelector(TISelector.Kind),
1160          getOpenMPContextTraitSelectorName(TISelector.Kind)});
1161     return;
1162   }
1163 
1164   if (!Tok.is(tok::l_paren)) {
1165     Diag(SelectorLoc, diag::warn_omp_ctx_selector_without_properties)
1166         << getOpenMPContextTraitSelectorName(TISelector.Kind)
1167         << getOpenMPContextTraitSetName(Set);
1168     return FinishSelector();
1169   }
1170 
1171   if (TISelector.Kind == TraitSelector::user_condition) {
1172     SourceLocation RLoc;
1173     ExprResult Condition = ParseOpenMPParensExpr("user condition", RLoc);
1174     if (!Condition.isUsable())
1175       return FinishSelector();
1176     TISelector.ScoreOrCondition = Condition.get();
1177     TISelector.Properties.push_back(
1178         {TraitProperty::user_condition_unknown, "<condition>"});
1179     return;
1180   }
1181 
1182   BalancedDelimiterTracker BDT(*this, tok::l_paren,
1183                                tok::annot_pragma_openmp_end);
1184   // Parse '('.
1185   (void)BDT.consumeOpen();
1186 
1187   SourceLocation ScoreLoc = Tok.getLocation();
1188   ExprResult Score = parseContextScore(*this);
1189 
1190   if (!AllowsTraitScore && !Score.isUnset()) {
1191     if (Score.isUsable()) {
1192       Diag(ScoreLoc, diag::warn_omp_ctx_incompatible_score_for_property)
1193           << getOpenMPContextTraitSelectorName(TISelector.Kind)
1194           << getOpenMPContextTraitSetName(Set) << Score.get();
1195     } else {
1196       Diag(ScoreLoc, diag::warn_omp_ctx_incompatible_score_for_property)
1197           << getOpenMPContextTraitSelectorName(TISelector.Kind)
1198           << getOpenMPContextTraitSetName(Set) << "<invalid>";
1199     }
1200     Score = ExprResult();
1201   }
1202 
1203   if (Score.isUsable())
1204     TISelector.ScoreOrCondition = Score.get();
1205 
1206   llvm::StringMap<SourceLocation> SeenProperties;
1207   do {
1208     parseOMPContextProperty(TISelector, Set, SeenProperties);
1209   } while (TryConsumeToken(tok::comma));
1210 
1211   // Parse ')'.
1212   BDT.consumeClose();
1213 }
1214 
1215 void Parser::parseOMPTraitSetKind(OMPTraitSet &TISet,
1216                                   llvm::StringMap<SourceLocation> &Seen) {
1217   TISet.Kind = TraitSet::invalid;
1218 
1219   SourceLocation NameLoc = Tok.getLocation();
1220   StringRef Name = getNameFromIdOrString(*this, Tok, CONTEXT_SELECTOR_SET_LVL);
1221   if (Name.empty()) {
1222     Diag(Tok.getLocation(), diag::note_omp_declare_variant_ctx_options)
1223         << CONTEXT_SELECTOR_SET_LVL << listOpenMPContextTraitSets();
1224     return;
1225   }
1226 
1227   TISet.Kind = getOpenMPContextTraitSetKind(Name);
1228   if (TISet.Kind != TraitSet::invalid) {
1229     if (checkForDuplicates(*this, Name, NameLoc, Seen,
1230                            CONTEXT_SELECTOR_SET_LVL))
1231       TISet.Kind = TraitSet::invalid;
1232     return;
1233   }
1234 
1235   // It follows diagnosis and helping notes.
1236   Diag(NameLoc, diag::warn_omp_declare_variant_ctx_not_a_set) << Name;
1237 
1238   TraitSelector SelectorForName = getOpenMPContextTraitSelectorKind(Name);
1239   if (SelectorForName != TraitSelector::invalid) {
1240     Diag(NameLoc, diag::note_omp_declare_variant_ctx_is_a)
1241         << Name << CONTEXT_SELECTOR_LVL << CONTEXT_SELECTOR_SET_LVL;
1242     bool AllowsTraitScore = false;
1243     bool RequiresProperty = false;
1244     isValidTraitSelectorForTraitSet(
1245         SelectorForName, getOpenMPContextTraitSetForSelector(SelectorForName),
1246         AllowsTraitScore, RequiresProperty);
1247     Diag(NameLoc, diag::note_omp_declare_variant_ctx_try)
1248         << getOpenMPContextTraitSetName(
1249                getOpenMPContextTraitSetForSelector(SelectorForName))
1250         << Name << (RequiresProperty ? "(<property-name>)" : "");
1251     return;
1252   }
1253   for (const auto &PotentialSet :
1254        {TraitSet::construct, TraitSet::user, TraitSet::implementation,
1255         TraitSet::device}) {
1256     TraitProperty PropertyForName = getOpenMPContextTraitPropertyKind(
1257         PotentialSet, TraitSelector::invalid, Name);
1258     if (PropertyForName == TraitProperty::invalid)
1259       continue;
1260     Diag(NameLoc, diag::note_omp_declare_variant_ctx_is_a)
1261         << Name << CONTEXT_TRAIT_LVL << CONTEXT_SELECTOR_SET_LVL;
1262     Diag(NameLoc, diag::note_omp_declare_variant_ctx_try)
1263         << getOpenMPContextTraitSetName(
1264                getOpenMPContextTraitSetForProperty(PropertyForName))
1265         << getOpenMPContextTraitSelectorName(
1266                getOpenMPContextTraitSelectorForProperty(PropertyForName))
1267         << ("(" + Name + ")").str();
1268     return;
1269   }
1270   Diag(NameLoc, diag::note_omp_declare_variant_ctx_options)
1271       << CONTEXT_SELECTOR_SET_LVL << listOpenMPContextTraitSets();
1272 }
1273 
1274 /// Parses an OpenMP context selector set.
1275 ///
1276 /// <trait-set-selector-name> '=' '{' <trait-selector> [, <trait-selector>]* '}'
1277 void Parser::parseOMPContextSelectorSet(
1278     OMPTraitSet &TISet, llvm::StringMap<SourceLocation> &SeenSets) {
1279   auto OuterBC = BraceCount;
1280 
1281   // If anything went wrong we issue an error or warning and then skip the rest
1282   // of the set. However, commas are ambiguous so we look for the nesting
1283   // of braces here as well.
1284   auto FinishSelectorSet = [this, OuterBC]() -> void {
1285     bool Done = false;
1286     while (!Done) {
1287       while (!SkipUntil({tok::comma, tok::r_brace, tok::r_paren,
1288                          tok::annot_pragma_openmp_end},
1289                         StopBeforeMatch))
1290         ;
1291       if (Tok.is(tok::r_brace) && OuterBC > BraceCount)
1292         (void)ConsumeBrace();
1293       if (OuterBC <= BraceCount) {
1294         Done = true;
1295         break;
1296       }
1297       if (!Tok.is(tok::comma) && !Tok.is(tok::r_brace)) {
1298         Done = true;
1299         break;
1300       }
1301       (void)ConsumeAnyToken();
1302     }
1303     Diag(Tok.getLocation(), diag::note_omp_declare_variant_ctx_continue_here)
1304         << CONTEXT_SELECTOR_SET_LVL;
1305   };
1306 
1307   parseOMPTraitSetKind(TISet, SeenSets);
1308   if (TISet.Kind == TraitSet::invalid)
1309     return FinishSelectorSet();
1310 
1311   // Parse '='.
1312   if (!TryConsumeToken(tok::equal))
1313     Diag(Tok.getLocation(), diag::warn_omp_declare_variant_expected)
1314         << "="
1315         << ("context set name \"" + getOpenMPContextTraitSetName(TISet.Kind) +
1316             "\"")
1317                .str();
1318 
1319   // Parse '{'.
1320   if (Tok.is(tok::l_brace)) {
1321     (void)ConsumeBrace();
1322   } else {
1323     Diag(Tok.getLocation(), diag::warn_omp_declare_variant_expected)
1324         << "{"
1325         << ("'=' that follows the context set name \"" +
1326             getOpenMPContextTraitSetName(TISet.Kind) + "\"")
1327                .str();
1328   }
1329 
1330   llvm::StringMap<SourceLocation> SeenSelectors;
1331   do {
1332     OMPTraitSelector TISelector;
1333     parseOMPContextSelector(TISelector, TISet.Kind, SeenSelectors);
1334     if (TISelector.Kind != TraitSelector::invalid &&
1335         !TISelector.Properties.empty())
1336       TISet.Selectors.push_back(TISelector);
1337   } while (TryConsumeToken(tok::comma));
1338 
1339   // Parse '}'.
1340   if (Tok.is(tok::r_brace)) {
1341     (void)ConsumeBrace();
1342   } else {
1343     Diag(Tok.getLocation(), diag::warn_omp_declare_variant_expected)
1344         << "}"
1345         << ("context selectors for the context set \"" +
1346             getOpenMPContextTraitSetName(TISet.Kind) + "\"")
1347                .str();
1348   }
1349 }
1350 
1351 /// Parse OpenMP context selectors:
1352 ///
1353 /// <trait-set-selector> [, <trait-set-selector>]*
1354 bool Parser::parseOMPContextSelectors(SourceLocation Loc, OMPTraitInfo &TI) {
1355   llvm::StringMap<SourceLocation> SeenSets;
1356   do {
1357     OMPTraitSet TISet;
1358     parseOMPContextSelectorSet(TISet, SeenSets);
1359     if (TISet.Kind != TraitSet::invalid && !TISet.Selectors.empty())
1360       TI.Sets.push_back(TISet);
1361   } while (TryConsumeToken(tok::comma));
1362 
1363   return false;
1364 }
1365 
1366 /// Parse clauses for '#pragma omp declare variant ( variant-func-id ) clause'.
1367 void Parser::ParseOMPDeclareVariantClauses(Parser::DeclGroupPtrTy Ptr,
1368                                            CachedTokens &Toks,
1369                                            SourceLocation Loc) {
1370   PP.EnterToken(Tok, /*IsReinject*/ true);
1371   PP.EnterTokenStream(Toks, /*DisableMacroExpansion=*/true,
1372                       /*IsReinject*/ true);
1373   // Consume the previously pushed token.
1374   ConsumeAnyToken(/*ConsumeCodeCompletionTok=*/true);
1375   ConsumeAnyToken(/*ConsumeCodeCompletionTok=*/true);
1376 
1377   FNContextRAII FnContext(*this, Ptr);
1378   // Parse function declaration id.
1379   SourceLocation RLoc;
1380   // Parse with IsAddressOfOperand set to true to parse methods as DeclRefExprs
1381   // instead of MemberExprs.
1382   ExprResult AssociatedFunction;
1383   {
1384     // Do not mark function as is used to prevent its emission if this is the
1385     // only place where it is used.
1386     EnterExpressionEvaluationContext Unevaluated(
1387         Actions, Sema::ExpressionEvaluationContext::Unevaluated);
1388     AssociatedFunction = ParseOpenMPParensExpr(
1389         getOpenMPDirectiveName(OMPD_declare_variant), RLoc,
1390         /*IsAddressOfOperand=*/true);
1391   }
1392   if (!AssociatedFunction.isUsable()) {
1393     if (!Tok.is(tok::annot_pragma_openmp_end))
1394       while (!SkipUntil(tok::annot_pragma_openmp_end, StopBeforeMatch))
1395         ;
1396     // Skip the last annot_pragma_openmp_end.
1397     (void)ConsumeAnnotationToken();
1398     return;
1399   }
1400 
1401   OMPTraitInfo *ParentTI = Actions.getOMPTraitInfoForSurroundingScope();
1402   ASTContext &ASTCtx = Actions.getASTContext();
1403   OMPTraitInfo &TI = ASTCtx.getNewOMPTraitInfo();
1404   if (parseOMPDeclareVariantMatchClause(Loc, TI, ParentTI))
1405     return;
1406 
1407   Optional<std::pair<FunctionDecl *, Expr *>> DeclVarData =
1408       Actions.checkOpenMPDeclareVariantFunction(
1409           Ptr, AssociatedFunction.get(), TI,
1410           SourceRange(Loc, Tok.getLocation()));
1411 
1412   // Skip last tokens.
1413   while (Tok.isNot(tok::annot_pragma_openmp_end))
1414     ConsumeAnyToken();
1415   if (DeclVarData && !TI.Sets.empty())
1416     Actions.ActOnOpenMPDeclareVariantDirective(
1417         DeclVarData->first, DeclVarData->second, TI,
1418         SourceRange(Loc, Tok.getLocation()));
1419 
1420   // Skip the last annot_pragma_openmp_end.
1421   (void)ConsumeAnnotationToken();
1422 }
1423 
1424 bool Parser::parseOMPDeclareVariantMatchClause(SourceLocation Loc,
1425                                                OMPTraitInfo &TI,
1426                                                OMPTraitInfo *ParentTI) {
1427   // Parse 'match'.
1428   OpenMPClauseKind CKind = Tok.isAnnotation()
1429                                ? OMPC_unknown
1430                                : getOpenMPClauseKind(PP.getSpelling(Tok));
1431   if (CKind != OMPC_match) {
1432     Diag(Tok.getLocation(), diag::err_omp_declare_variant_wrong_clause)
1433         << getOpenMPClauseName(OMPC_match);
1434     while (!SkipUntil(tok::annot_pragma_openmp_end, Parser::StopBeforeMatch))
1435       ;
1436     // Skip the last annot_pragma_openmp_end.
1437     (void)ConsumeAnnotationToken();
1438     return true;
1439   }
1440   (void)ConsumeToken();
1441   // Parse '('.
1442   BalancedDelimiterTracker T(*this, tok::l_paren, tok::annot_pragma_openmp_end);
1443   if (T.expectAndConsume(diag::err_expected_lparen_after,
1444                          getOpenMPClauseName(OMPC_match).data())) {
1445     while (!SkipUntil(tok::annot_pragma_openmp_end, StopBeforeMatch))
1446       ;
1447     // Skip the last annot_pragma_openmp_end.
1448     (void)ConsumeAnnotationToken();
1449     return true;
1450   }
1451 
1452   // Parse inner context selectors.
1453   parseOMPContextSelectors(Loc, TI);
1454 
1455   // Parse ')'
1456   (void)T.consumeClose();
1457 
1458   if (!ParentTI)
1459     return false;
1460 
1461   // Merge the parent/outer trait info into the one we just parsed and diagnose
1462   // problems.
1463   // TODO: Keep some source location in the TI to provide better diagnostics.
1464   // TODO: Perform some kind of equivalence check on the condition and score
1465   //       expressions.
1466   for (const OMPTraitSet &ParentSet : ParentTI->Sets) {
1467     bool MergedSet = false;
1468     for (OMPTraitSet &Set : TI.Sets) {
1469       if (Set.Kind != ParentSet.Kind)
1470         continue;
1471       MergedSet = true;
1472       for (const OMPTraitSelector &ParentSelector : ParentSet.Selectors) {
1473         bool MergedSelector = false;
1474         for (OMPTraitSelector &Selector : Set.Selectors) {
1475           if (Selector.Kind != ParentSelector.Kind)
1476             continue;
1477           MergedSelector = true;
1478           for (const OMPTraitProperty &ParentProperty :
1479                ParentSelector.Properties) {
1480             bool MergedProperty = false;
1481             for (OMPTraitProperty &Property : Selector.Properties) {
1482               // Ignore "equivalent" properties.
1483               if (Property.Kind != ParentProperty.Kind)
1484                 continue;
1485 
1486               // If the kind is the same but the raw string not, we don't want
1487               // to skip out on the property.
1488               MergedProperty |= Property.RawString == ParentProperty.RawString;
1489 
1490               if (Property.RawString == ParentProperty.RawString &&
1491                   Selector.ScoreOrCondition == ParentSelector.ScoreOrCondition)
1492                 continue;
1493 
1494               if (Selector.Kind == llvm::omp::TraitSelector::user_condition) {
1495                 Diag(Loc, diag::err_omp_declare_variant_nested_user_condition);
1496               } else if (Selector.ScoreOrCondition !=
1497                          ParentSelector.ScoreOrCondition) {
1498                 Diag(Loc, diag::err_omp_declare_variant_duplicate_nested_trait)
1499                     << getOpenMPContextTraitPropertyName(
1500                            ParentProperty.Kind, ParentProperty.RawString)
1501                     << getOpenMPContextTraitSelectorName(ParentSelector.Kind)
1502                     << getOpenMPContextTraitSetName(ParentSet.Kind);
1503               }
1504             }
1505             if (!MergedProperty)
1506               Selector.Properties.push_back(ParentProperty);
1507           }
1508         }
1509         if (!MergedSelector)
1510           Set.Selectors.push_back(ParentSelector);
1511       }
1512     }
1513     if (!MergedSet)
1514       TI.Sets.push_back(ParentSet);
1515   }
1516 
1517   return false;
1518 }
1519 
1520 /// `omp assumes` or `omp begin/end assumes` <clause> [[,]<clause>]...
1521 /// where
1522 ///
1523 ///   clause:
1524 ///     'ext_IMPL_DEFINED'
1525 ///     'absent' '(' directive-name [, directive-name]* ')'
1526 ///     'contains' '(' directive-name [, directive-name]* ')'
1527 ///     'holds' '(' scalar-expression ')'
1528 ///     'no_openmp'
1529 ///     'no_openmp_routines'
1530 ///     'no_parallelism'
1531 ///
1532 void Parser::ParseOpenMPAssumesDirective(OpenMPDirectiveKind DKind,
1533                                          SourceLocation Loc) {
1534   SmallVector<StringRef, 4> Assumptions;
1535   bool SkippedClauses = false;
1536 
1537   auto SkipBraces = [&](llvm::StringRef Spelling, bool IssueNote) {
1538     BalancedDelimiterTracker T(*this, tok::l_paren,
1539                                tok::annot_pragma_openmp_end);
1540     if (T.expectAndConsume(diag::err_expected_lparen_after, Spelling.data()))
1541       return;
1542     T.skipToEnd();
1543     if (IssueNote && T.getCloseLocation().isValid())
1544       Diag(T.getCloseLocation(),
1545            diag::note_omp_assumption_clause_continue_here);
1546   };
1547 
1548   /// Helper to determine which AssumptionClauseMapping (ACM) in the
1549   /// AssumptionClauseMappings table matches \p RawString. The return value is
1550   /// the index of the matching ACM into the table or -1 if there was no match.
1551   auto MatchACMClause = [&](StringRef RawString) {
1552     llvm::StringSwitch<int> SS(RawString);
1553     unsigned ACMIdx = 0;
1554     for (const AssumptionClauseMappingInfo &ACMI : AssumptionClauseMappings) {
1555       if (ACMI.StartsWith)
1556         SS.StartsWith(ACMI.Identifier, ACMIdx++);
1557       else
1558         SS.Case(ACMI.Identifier, ACMIdx++);
1559     }
1560     return SS.Default(-1);
1561   };
1562 
1563   while (Tok.isNot(tok::annot_pragma_openmp_end)) {
1564     IdentifierInfo *II = nullptr;
1565     SourceLocation StartLoc = Tok.getLocation();
1566     int Idx = -1;
1567     if (Tok.isAnyIdentifier()) {
1568       II = Tok.getIdentifierInfo();
1569       Idx = MatchACMClause(II->getName());
1570     }
1571     ConsumeAnyToken();
1572 
1573     bool NextIsLPar = Tok.is(tok::l_paren);
1574     // Handle unknown clauses by skipping them.
1575     if (Idx == -1) {
1576       Diag(StartLoc, diag::warn_omp_unknown_assumption_clause_missing_id)
1577           << llvm::omp::getOpenMPDirectiveName(DKind)
1578           << llvm::omp::getAllAssumeClauseOptions() << NextIsLPar;
1579       if (NextIsLPar)
1580         SkipBraces(II ? II->getName() : "", /* IssueNote */ true);
1581       SkippedClauses = true;
1582       continue;
1583     }
1584     const AssumptionClauseMappingInfo &ACMI = AssumptionClauseMappings[Idx];
1585     if (ACMI.HasDirectiveList || ACMI.HasExpression) {
1586       // TODO: We ignore absent, contains, and holds assumptions for now. We
1587       //       also do not verify the content in the parenthesis at all.
1588       SkippedClauses = true;
1589       SkipBraces(II->getName(), /* IssueNote */ false);
1590       continue;
1591     }
1592 
1593     if (NextIsLPar) {
1594       Diag(Tok.getLocation(),
1595            diag::warn_omp_unknown_assumption_clause_without_args)
1596           << II;
1597       SkipBraces(II->getName(), /* IssueNote */ true);
1598     }
1599 
1600     assert(II && "Expected an identifier clause!");
1601     StringRef Assumption = II->getName();
1602     if (ACMI.StartsWith)
1603       Assumption = Assumption.substr(ACMI.Identifier.size());
1604     Assumptions.push_back(Assumption);
1605   }
1606 
1607   Actions.ActOnOpenMPAssumesDirective(Loc, DKind, Assumptions, SkippedClauses);
1608 }
1609 
1610 void Parser::ParseOpenMPEndAssumesDirective(SourceLocation Loc) {
1611   if (Actions.isInOpenMPAssumeScope())
1612     Actions.ActOnOpenMPEndAssumesDirective();
1613   else
1614     Diag(Loc, diag::err_expected_begin_assumes);
1615 }
1616 
1617 /// Parsing of simple OpenMP clauses like 'default' or 'proc_bind'.
1618 ///
1619 ///    default-clause:
1620 ///         'default' '(' 'none' | 'shared'  | 'firstprivate' ')
1621 ///
1622 ///    proc_bind-clause:
1623 ///         'proc_bind' '(' 'master' | 'close' | 'spread' ')
1624 ///
1625 ///    device_type-clause:
1626 ///         'device_type' '(' 'host' | 'nohost' | 'any' )'
1627 namespace {
1628 struct SimpleClauseData {
1629   unsigned Type;
1630   SourceLocation Loc;
1631   SourceLocation LOpen;
1632   SourceLocation TypeLoc;
1633   SourceLocation RLoc;
1634   SimpleClauseData(unsigned Type, SourceLocation Loc, SourceLocation LOpen,
1635                    SourceLocation TypeLoc, SourceLocation RLoc)
1636       : Type(Type), Loc(Loc), LOpen(LOpen), TypeLoc(TypeLoc), RLoc(RLoc) {}
1637 };
1638 } // anonymous namespace
1639 
1640 static Optional<SimpleClauseData>
1641 parseOpenMPSimpleClause(Parser &P, OpenMPClauseKind Kind) {
1642   const Token &Tok = P.getCurToken();
1643   SourceLocation Loc = Tok.getLocation();
1644   SourceLocation LOpen = P.ConsumeToken();
1645   // Parse '('.
1646   BalancedDelimiterTracker T(P, tok::l_paren, tok::annot_pragma_openmp_end);
1647   if (T.expectAndConsume(diag::err_expected_lparen_after,
1648                          getOpenMPClauseName(Kind).data()))
1649     return llvm::None;
1650 
1651   unsigned Type = getOpenMPSimpleClauseType(
1652       Kind, Tok.isAnnotation() ? "" : P.getPreprocessor().getSpelling(Tok),
1653       P.getLangOpts().OpenMP);
1654   SourceLocation TypeLoc = Tok.getLocation();
1655   if (Tok.isNot(tok::r_paren) && Tok.isNot(tok::comma) &&
1656       Tok.isNot(tok::annot_pragma_openmp_end))
1657     P.ConsumeAnyToken();
1658 
1659   // Parse ')'.
1660   SourceLocation RLoc = Tok.getLocation();
1661   if (!T.consumeClose())
1662     RLoc = T.getCloseLocation();
1663 
1664   return SimpleClauseData(Type, Loc, LOpen, TypeLoc, RLoc);
1665 }
1666 
1667 Parser::DeclGroupPtrTy Parser::ParseOMPDeclareTargetClauses() {
1668   // OpenMP 4.5 syntax with list of entities.
1669   Sema::NamedDeclSetType SameDirectiveDecls;
1670   SmallVector<std::tuple<OMPDeclareTargetDeclAttr::MapTypeTy, SourceLocation,
1671                          NamedDecl *>,
1672               4>
1673       DeclareTargetDecls;
1674   OMPDeclareTargetDeclAttr::DevTypeTy DT = OMPDeclareTargetDeclAttr::DT_Any;
1675   SourceLocation DeviceTypeLoc;
1676   while (Tok.isNot(tok::annot_pragma_openmp_end)) {
1677     OMPDeclareTargetDeclAttr::MapTypeTy MT = OMPDeclareTargetDeclAttr::MT_To;
1678     if (Tok.is(tok::identifier)) {
1679       IdentifierInfo *II = Tok.getIdentifierInfo();
1680       StringRef ClauseName = II->getName();
1681       bool IsDeviceTypeClause =
1682           getLangOpts().OpenMP >= 50 &&
1683           getOpenMPClauseKind(ClauseName) == OMPC_device_type;
1684       // Parse 'to|link|device_type' clauses.
1685       if (!OMPDeclareTargetDeclAttr::ConvertStrToMapTypeTy(ClauseName, MT) &&
1686           !IsDeviceTypeClause) {
1687         Diag(Tok, diag::err_omp_declare_target_unexpected_clause)
1688             << ClauseName << (getLangOpts().OpenMP >= 50 ? 1 : 0);
1689         break;
1690       }
1691       // Parse 'device_type' clause and go to next clause if any.
1692       if (IsDeviceTypeClause) {
1693         Optional<SimpleClauseData> DevTypeData =
1694             parseOpenMPSimpleClause(*this, OMPC_device_type);
1695         if (DevTypeData.hasValue()) {
1696           if (DeviceTypeLoc.isValid()) {
1697             // We already saw another device_type clause, diagnose it.
1698             Diag(DevTypeData.getValue().Loc,
1699                  diag::warn_omp_more_one_device_type_clause);
1700           }
1701           switch (static_cast<OpenMPDeviceType>(DevTypeData.getValue().Type)) {
1702           case OMPC_DEVICE_TYPE_any:
1703             DT = OMPDeclareTargetDeclAttr::DT_Any;
1704             break;
1705           case OMPC_DEVICE_TYPE_host:
1706             DT = OMPDeclareTargetDeclAttr::DT_Host;
1707             break;
1708           case OMPC_DEVICE_TYPE_nohost:
1709             DT = OMPDeclareTargetDeclAttr::DT_NoHost;
1710             break;
1711           case OMPC_DEVICE_TYPE_unknown:
1712             llvm_unreachable("Unexpected device_type");
1713           }
1714           DeviceTypeLoc = DevTypeData.getValue().Loc;
1715         }
1716         continue;
1717       }
1718       ConsumeToken();
1719     }
1720     auto &&Callback = [this, MT, &DeclareTargetDecls, &SameDirectiveDecls](
1721                           CXXScopeSpec &SS, DeclarationNameInfo NameInfo) {
1722       NamedDecl *ND = Actions.lookupOpenMPDeclareTargetName(
1723           getCurScope(), SS, NameInfo, SameDirectiveDecls);
1724       if (ND)
1725         DeclareTargetDecls.emplace_back(MT, NameInfo.getLoc(), ND);
1726     };
1727     if (ParseOpenMPSimpleVarList(OMPD_declare_target, Callback,
1728                                  /*AllowScopeSpecifier=*/true))
1729       break;
1730 
1731     // Consume optional ','.
1732     if (Tok.is(tok::comma))
1733       ConsumeToken();
1734   }
1735   SkipUntil(tok::annot_pragma_openmp_end, StopBeforeMatch);
1736   ConsumeAnyToken();
1737   for (auto &MTLocDecl : DeclareTargetDecls) {
1738     OMPDeclareTargetDeclAttr::MapTypeTy MT;
1739     SourceLocation Loc;
1740     NamedDecl *ND;
1741     std::tie(MT, Loc, ND) = MTLocDecl;
1742     // device_type clause is applied only to functions.
1743     Actions.ActOnOpenMPDeclareTargetName(
1744         ND, Loc, MT, isa<VarDecl>(ND) ? OMPDeclareTargetDeclAttr::DT_Any : DT);
1745   }
1746   SmallVector<Decl *, 4> Decls(SameDirectiveDecls.begin(),
1747                                SameDirectiveDecls.end());
1748   if (Decls.empty())
1749     return DeclGroupPtrTy();
1750   return Actions.BuildDeclaratorGroup(Decls);
1751 }
1752 
1753 void Parser::skipUntilPragmaOpenMPEnd(OpenMPDirectiveKind DKind) {
1754   // The last seen token is annot_pragma_openmp_end - need to check for
1755   // extra tokens.
1756   if (Tok.is(tok::annot_pragma_openmp_end))
1757     return;
1758 
1759   Diag(Tok, diag::warn_omp_extra_tokens_at_eol)
1760       << getOpenMPDirectiveName(DKind);
1761   while (Tok.isNot(tok::annot_pragma_openmp_end))
1762     ConsumeAnyToken();
1763 }
1764 
1765 void Parser::parseOMPEndDirective(OpenMPDirectiveKind BeginKind,
1766                                   OpenMPDirectiveKind ExpectedKind,
1767                                   OpenMPDirectiveKind FoundKind,
1768                                   SourceLocation BeginLoc,
1769                                   SourceLocation FoundLoc,
1770                                   bool SkipUntilOpenMPEnd) {
1771   int DiagSelection = ExpectedKind == OMPD_end_declare_target ? 0 : 1;
1772 
1773   if (FoundKind == ExpectedKind) {
1774     ConsumeAnyToken();
1775     skipUntilPragmaOpenMPEnd(ExpectedKind);
1776     return;
1777   }
1778 
1779   Diag(FoundLoc, diag::err_expected_end_declare_target_or_variant)
1780       << DiagSelection;
1781   Diag(BeginLoc, diag::note_matching)
1782       << ("'#pragma omp " + getOpenMPDirectiveName(BeginKind) + "'").str();
1783   if (SkipUntilOpenMPEnd)
1784     SkipUntil(tok::annot_pragma_openmp_end, StopBeforeMatch);
1785 }
1786 
1787 void Parser::ParseOMPEndDeclareTargetDirective(OpenMPDirectiveKind DKind,
1788                                                SourceLocation DKLoc) {
1789   parseOMPEndDirective(OMPD_declare_target, OMPD_end_declare_target, DKind,
1790                        DKLoc, Tok.getLocation(),
1791                        /* SkipUntilOpenMPEnd */ false);
1792   // Skip the last annot_pragma_openmp_end.
1793   if (Tok.is(tok::annot_pragma_openmp_end))
1794     ConsumeAnnotationToken();
1795 }
1796 
1797 /// Parsing of declarative OpenMP directives.
1798 ///
1799 ///       threadprivate-directive:
1800 ///         annot_pragma_openmp 'threadprivate' simple-variable-list
1801 ///         annot_pragma_openmp_end
1802 ///
1803 ///       allocate-directive:
1804 ///         annot_pragma_openmp 'allocate' simple-variable-list [<clause>]
1805 ///         annot_pragma_openmp_end
1806 ///
1807 ///       declare-reduction-directive:
1808 ///        annot_pragma_openmp 'declare' 'reduction' [...]
1809 ///        annot_pragma_openmp_end
1810 ///
1811 ///       declare-mapper-directive:
1812 ///         annot_pragma_openmp 'declare' 'mapper' '(' [<mapper-identifer> ':']
1813 ///         <type> <var> ')' [<clause>[[,] <clause>] ... ]
1814 ///         annot_pragma_openmp_end
1815 ///
1816 ///       declare-simd-directive:
1817 ///         annot_pragma_openmp 'declare simd' {<clause> [,]}
1818 ///         annot_pragma_openmp_end
1819 ///         <function declaration/definition>
1820 ///
1821 ///       requires directive:
1822 ///         annot_pragma_openmp 'requires' <clause> [[[,] <clause>] ... ]
1823 ///         annot_pragma_openmp_end
1824 ///
1825 ///       assumes directive:
1826 ///         annot_pragma_openmp 'assumes' <clause> [[[,] <clause>] ... ]
1827 ///         annot_pragma_openmp_end
1828 ///       or
1829 ///         annot_pragma_openmp 'begin assumes' <clause> [[[,] <clause>] ... ]
1830 ///         annot_pragma_openmp 'end assumes'
1831 ///         annot_pragma_openmp_end
1832 ///
1833 Parser::DeclGroupPtrTy Parser::ParseOpenMPDeclarativeDirectiveWithExtDecl(
1834     AccessSpecifier &AS, ParsedAttributesWithRange &Attrs, bool Delayed,
1835     DeclSpec::TST TagType, Decl *Tag) {
1836   assert(Tok.is(tok::annot_pragma_openmp) && "Not an OpenMP directive!");
1837   ParsingOpenMPDirectiveRAII DirScope(*this);
1838   ParenBraceBracketBalancer BalancerRAIIObj(*this);
1839 
1840   SourceLocation Loc;
1841   OpenMPDirectiveKind DKind;
1842   if (Delayed) {
1843     TentativeParsingAction TPA(*this);
1844     Loc = ConsumeAnnotationToken();
1845     DKind = parseOpenMPDirectiveKind(*this);
1846     if (DKind == OMPD_declare_reduction || DKind == OMPD_declare_mapper) {
1847       // Need to delay parsing until completion of the parent class.
1848       TPA.Revert();
1849       CachedTokens Toks;
1850       unsigned Cnt = 1;
1851       Toks.push_back(Tok);
1852       while (Cnt && Tok.isNot(tok::eof)) {
1853         (void)ConsumeAnyToken();
1854         if (Tok.is(tok::annot_pragma_openmp))
1855           ++Cnt;
1856         else if (Tok.is(tok::annot_pragma_openmp_end))
1857           --Cnt;
1858         Toks.push_back(Tok);
1859       }
1860       // Skip last annot_pragma_openmp_end.
1861       if (Cnt == 0)
1862         (void)ConsumeAnyToken();
1863       auto *LP = new LateParsedPragma(this, AS);
1864       LP->takeToks(Toks);
1865       getCurrentClass().LateParsedDeclarations.push_back(LP);
1866       return nullptr;
1867     }
1868     TPA.Commit();
1869   } else {
1870     Loc = ConsumeAnnotationToken();
1871     DKind = parseOpenMPDirectiveKind(*this);
1872   }
1873 
1874   switch (DKind) {
1875   case OMPD_threadprivate: {
1876     ConsumeToken();
1877     DeclDirectiveListParserHelper Helper(this, DKind);
1878     if (!ParseOpenMPSimpleVarList(DKind, Helper,
1879                                   /*AllowScopeSpecifier=*/true)) {
1880       skipUntilPragmaOpenMPEnd(DKind);
1881       // Skip the last annot_pragma_openmp_end.
1882       ConsumeAnnotationToken();
1883       return Actions.ActOnOpenMPThreadprivateDirective(Loc,
1884                                                        Helper.getIdentifiers());
1885     }
1886     break;
1887   }
1888   case OMPD_allocate: {
1889     ConsumeToken();
1890     DeclDirectiveListParserHelper Helper(this, DKind);
1891     if (!ParseOpenMPSimpleVarList(DKind, Helper,
1892                                   /*AllowScopeSpecifier=*/true)) {
1893       SmallVector<OMPClause *, 1> Clauses;
1894       if (Tok.isNot(tok::annot_pragma_openmp_end)) {
1895         SmallVector<llvm::PointerIntPair<OMPClause *, 1, bool>,
1896                     llvm::omp::Clause_enumSize + 1>
1897             FirstClauses(llvm::omp::Clause_enumSize + 1);
1898         while (Tok.isNot(tok::annot_pragma_openmp_end)) {
1899           OpenMPClauseKind CKind =
1900               Tok.isAnnotation() ? OMPC_unknown
1901                                  : getOpenMPClauseKind(PP.getSpelling(Tok));
1902           Actions.StartOpenMPClause(CKind);
1903           OMPClause *Clause = ParseOpenMPClause(
1904               OMPD_allocate, CKind, !FirstClauses[unsigned(CKind)].getInt());
1905           SkipUntil(tok::comma, tok::identifier, tok::annot_pragma_openmp_end,
1906                     StopBeforeMatch);
1907           FirstClauses[unsigned(CKind)].setInt(true);
1908           if (Clause != nullptr)
1909             Clauses.push_back(Clause);
1910           if (Tok.is(tok::annot_pragma_openmp_end)) {
1911             Actions.EndOpenMPClause();
1912             break;
1913           }
1914           // Skip ',' if any.
1915           if (Tok.is(tok::comma))
1916             ConsumeToken();
1917           Actions.EndOpenMPClause();
1918         }
1919         skipUntilPragmaOpenMPEnd(DKind);
1920       }
1921       // Skip the last annot_pragma_openmp_end.
1922       ConsumeAnnotationToken();
1923       return Actions.ActOnOpenMPAllocateDirective(Loc, Helper.getIdentifiers(),
1924                                                   Clauses);
1925     }
1926     break;
1927   }
1928   case OMPD_requires: {
1929     SourceLocation StartLoc = ConsumeToken();
1930     SmallVector<OMPClause *, 5> Clauses;
1931     SmallVector<llvm::PointerIntPair<OMPClause *, 1, bool>,
1932                 llvm::omp::Clause_enumSize + 1>
1933         FirstClauses(llvm::omp::Clause_enumSize + 1);
1934     if (Tok.is(tok::annot_pragma_openmp_end)) {
1935       Diag(Tok, diag::err_omp_expected_clause)
1936           << getOpenMPDirectiveName(OMPD_requires);
1937       break;
1938     }
1939     while (Tok.isNot(tok::annot_pragma_openmp_end)) {
1940       OpenMPClauseKind CKind = Tok.isAnnotation()
1941                                    ? OMPC_unknown
1942                                    : getOpenMPClauseKind(PP.getSpelling(Tok));
1943       Actions.StartOpenMPClause(CKind);
1944       OMPClause *Clause = ParseOpenMPClause(
1945           OMPD_requires, CKind, !FirstClauses[unsigned(CKind)].getInt());
1946       SkipUntil(tok::comma, tok::identifier, tok::annot_pragma_openmp_end,
1947                 StopBeforeMatch);
1948       FirstClauses[unsigned(CKind)].setInt(true);
1949       if (Clause != nullptr)
1950         Clauses.push_back(Clause);
1951       if (Tok.is(tok::annot_pragma_openmp_end)) {
1952         Actions.EndOpenMPClause();
1953         break;
1954       }
1955       // Skip ',' if any.
1956       if (Tok.is(tok::comma))
1957         ConsumeToken();
1958       Actions.EndOpenMPClause();
1959     }
1960     // Consume final annot_pragma_openmp_end
1961     if (Clauses.empty()) {
1962       Diag(Tok, diag::err_omp_expected_clause)
1963           << getOpenMPDirectiveName(OMPD_requires);
1964       ConsumeAnnotationToken();
1965       return nullptr;
1966     }
1967     ConsumeAnnotationToken();
1968     return Actions.ActOnOpenMPRequiresDirective(StartLoc, Clauses);
1969   }
1970   case OMPD_assumes:
1971   case OMPD_begin_assumes:
1972     ParseOpenMPAssumesDirective(DKind, ConsumeToken());
1973     break;
1974   case OMPD_end_assumes:
1975     ParseOpenMPEndAssumesDirective(ConsumeToken());
1976     break;
1977   case OMPD_declare_reduction:
1978     ConsumeToken();
1979     if (DeclGroupPtrTy Res = ParseOpenMPDeclareReductionDirective(AS)) {
1980       skipUntilPragmaOpenMPEnd(OMPD_declare_reduction);
1981       // Skip the last annot_pragma_openmp_end.
1982       ConsumeAnnotationToken();
1983       return Res;
1984     }
1985     break;
1986   case OMPD_declare_mapper: {
1987     ConsumeToken();
1988     if (DeclGroupPtrTy Res = ParseOpenMPDeclareMapperDirective(AS)) {
1989       // Skip the last annot_pragma_openmp_end.
1990       ConsumeAnnotationToken();
1991       return Res;
1992     }
1993     break;
1994   }
1995   case OMPD_begin_declare_variant: {
1996     // The syntax is:
1997     // { #pragma omp begin declare variant clause }
1998     // <function-declaration-or-definition-sequence>
1999     // { #pragma omp end declare variant }
2000     //
2001     ConsumeToken();
2002     OMPTraitInfo *ParentTI = Actions.getOMPTraitInfoForSurroundingScope();
2003     ASTContext &ASTCtx = Actions.getASTContext();
2004     OMPTraitInfo &TI = ASTCtx.getNewOMPTraitInfo();
2005     if (parseOMPDeclareVariantMatchClause(Loc, TI, ParentTI))
2006       break;
2007 
2008     // Skip last tokens.
2009     skipUntilPragmaOpenMPEnd(OMPD_begin_declare_variant);
2010 
2011     ParsingOpenMPDirectiveRAII NormalScope(*this, /*Value=*/false);
2012 
2013     VariantMatchInfo VMI;
2014     TI.getAsVariantMatchInfo(ASTCtx, VMI);
2015 
2016     std::function<void(StringRef)> DiagUnknownTrait = [this, Loc](
2017                                                           StringRef ISATrait) {
2018       // TODO Track the selector locations in a way that is accessible here to
2019       // improve the diagnostic location.
2020       Diag(Loc, diag::warn_unknown_begin_declare_variant_isa_trait) << ISATrait;
2021     };
2022     TargetOMPContext OMPCtx(ASTCtx, std::move(DiagUnknownTrait),
2023                             /* CurrentFunctionDecl */ nullptr);
2024 
2025     if (isVariantApplicableInContext(VMI, OMPCtx, /* DeviceSetOnly */ true)) {
2026       Actions.ActOnOpenMPBeginDeclareVariant(Loc, TI);
2027       break;
2028     }
2029 
2030     // Elide all the code till the matching end declare variant was found.
2031     unsigned Nesting = 1;
2032     SourceLocation DKLoc;
2033     OpenMPDirectiveKind DK = OMPD_unknown;
2034     do {
2035       DKLoc = Tok.getLocation();
2036       DK = parseOpenMPDirectiveKind(*this);
2037       if (DK == OMPD_end_declare_variant)
2038         --Nesting;
2039       else if (DK == OMPD_begin_declare_variant)
2040         ++Nesting;
2041       if (!Nesting || isEofOrEom())
2042         break;
2043       ConsumeAnyToken();
2044     } while (true);
2045 
2046     parseOMPEndDirective(OMPD_begin_declare_variant, OMPD_end_declare_variant,
2047                          DK, Loc, DKLoc, /* SkipUntilOpenMPEnd */ true);
2048     if (isEofOrEom())
2049       return nullptr;
2050     break;
2051   }
2052   case OMPD_end_declare_variant: {
2053     if (Actions.isInOpenMPDeclareVariantScope())
2054       Actions.ActOnOpenMPEndDeclareVariant();
2055     else
2056       Diag(Loc, diag::err_expected_begin_declare_variant);
2057     ConsumeToken();
2058     break;
2059   }
2060   case OMPD_declare_variant:
2061   case OMPD_declare_simd: {
2062     // The syntax is:
2063     // { #pragma omp declare {simd|variant} }
2064     // <function-declaration-or-definition>
2065     //
2066     CachedTokens Toks;
2067     Toks.push_back(Tok);
2068     ConsumeToken();
2069     while (Tok.isNot(tok::annot_pragma_openmp_end)) {
2070       Toks.push_back(Tok);
2071       ConsumeAnyToken();
2072     }
2073     Toks.push_back(Tok);
2074     ConsumeAnyToken();
2075 
2076     DeclGroupPtrTy Ptr;
2077     if (Tok.is(tok::annot_pragma_openmp)) {
2078       Ptr = ParseOpenMPDeclarativeDirectiveWithExtDecl(AS, Attrs, Delayed,
2079                                                        TagType, Tag);
2080     } else if (Tok.isNot(tok::r_brace) && !isEofOrEom()) {
2081       // Here we expect to see some function declaration.
2082       if (AS == AS_none) {
2083         assert(TagType == DeclSpec::TST_unspecified);
2084         MaybeParseCXX11Attributes(Attrs);
2085         ParsingDeclSpec PDS(*this);
2086         Ptr = ParseExternalDeclaration(Attrs, &PDS);
2087       } else {
2088         Ptr =
2089             ParseCXXClassMemberDeclarationWithPragmas(AS, Attrs, TagType, Tag);
2090       }
2091     }
2092     if (!Ptr) {
2093       Diag(Loc, diag::err_omp_decl_in_declare_simd_variant)
2094           << (DKind == OMPD_declare_simd ? 0 : 1);
2095       return DeclGroupPtrTy();
2096     }
2097     if (DKind == OMPD_declare_simd)
2098       return ParseOMPDeclareSimdClauses(Ptr, Toks, Loc);
2099     assert(DKind == OMPD_declare_variant &&
2100            "Expected declare variant directive only");
2101     ParseOMPDeclareVariantClauses(Ptr, Toks, Loc);
2102     return Ptr;
2103   }
2104   case OMPD_declare_target: {
2105     SourceLocation DTLoc = ConsumeAnyToken();
2106     if (Tok.isNot(tok::annot_pragma_openmp_end)) {
2107       return ParseOMPDeclareTargetClauses();
2108     }
2109 
2110     // Skip the last annot_pragma_openmp_end.
2111     ConsumeAnyToken();
2112 
2113     if (!Actions.ActOnStartOpenMPDeclareTargetDirective(DTLoc))
2114       return DeclGroupPtrTy();
2115 
2116     ParsingOpenMPDirectiveRAII NormalScope(*this, /*Value=*/false);
2117     llvm::SmallVector<Decl *, 4> Decls;
2118     DKind = parseOpenMPDirectiveKind(*this);
2119     while (DKind != OMPD_end_declare_target && Tok.isNot(tok::eof) &&
2120            Tok.isNot(tok::r_brace)) {
2121       DeclGroupPtrTy Ptr;
2122       // Here we expect to see some function declaration.
2123       if (AS == AS_none) {
2124         assert(TagType == DeclSpec::TST_unspecified);
2125         MaybeParseCXX11Attributes(Attrs);
2126         ParsingDeclSpec PDS(*this);
2127         Ptr = ParseExternalDeclaration(Attrs, &PDS);
2128       } else {
2129         Ptr =
2130             ParseCXXClassMemberDeclarationWithPragmas(AS, Attrs, TagType, Tag);
2131       }
2132       if (Ptr) {
2133         DeclGroupRef Ref = Ptr.get();
2134         Decls.append(Ref.begin(), Ref.end());
2135       }
2136       if (Tok.isAnnotation() && Tok.is(tok::annot_pragma_openmp)) {
2137         TentativeParsingAction TPA(*this);
2138         ConsumeAnnotationToken();
2139         DKind = parseOpenMPDirectiveKind(*this);
2140         if (DKind != OMPD_end_declare_target)
2141           TPA.Revert();
2142         else
2143           TPA.Commit();
2144       }
2145     }
2146 
2147     ParseOMPEndDeclareTargetDirective(DKind, DTLoc);
2148     Actions.ActOnFinishOpenMPDeclareTargetDirective();
2149     return Actions.BuildDeclaratorGroup(Decls);
2150   }
2151   case OMPD_unknown:
2152     Diag(Tok, diag::err_omp_unknown_directive);
2153     break;
2154   case OMPD_parallel:
2155   case OMPD_simd:
2156   case OMPD_tile:
2157   case OMPD_task:
2158   case OMPD_taskyield:
2159   case OMPD_barrier:
2160   case OMPD_taskwait:
2161   case OMPD_taskgroup:
2162   case OMPD_flush:
2163   case OMPD_depobj:
2164   case OMPD_scan:
2165   case OMPD_for:
2166   case OMPD_for_simd:
2167   case OMPD_sections:
2168   case OMPD_section:
2169   case OMPD_single:
2170   case OMPD_master:
2171   case OMPD_ordered:
2172   case OMPD_critical:
2173   case OMPD_parallel_for:
2174   case OMPD_parallel_for_simd:
2175   case OMPD_parallel_sections:
2176   case OMPD_parallel_master:
2177   case OMPD_atomic:
2178   case OMPD_target:
2179   case OMPD_teams:
2180   case OMPD_cancellation_point:
2181   case OMPD_cancel:
2182   case OMPD_target_data:
2183   case OMPD_target_enter_data:
2184   case OMPD_target_exit_data:
2185   case OMPD_target_parallel:
2186   case OMPD_target_parallel_for:
2187   case OMPD_taskloop:
2188   case OMPD_taskloop_simd:
2189   case OMPD_master_taskloop:
2190   case OMPD_master_taskloop_simd:
2191   case OMPD_parallel_master_taskloop:
2192   case OMPD_parallel_master_taskloop_simd:
2193   case OMPD_distribute:
2194   case OMPD_end_declare_target:
2195   case OMPD_target_update:
2196   case OMPD_distribute_parallel_for:
2197   case OMPD_distribute_parallel_for_simd:
2198   case OMPD_distribute_simd:
2199   case OMPD_target_parallel_for_simd:
2200   case OMPD_target_simd:
2201   case OMPD_teams_distribute:
2202   case OMPD_teams_distribute_simd:
2203   case OMPD_teams_distribute_parallel_for_simd:
2204   case OMPD_teams_distribute_parallel_for:
2205   case OMPD_target_teams:
2206   case OMPD_target_teams_distribute:
2207   case OMPD_target_teams_distribute_parallel_for:
2208   case OMPD_target_teams_distribute_parallel_for_simd:
2209   case OMPD_target_teams_distribute_simd:
2210     Diag(Tok, diag::err_omp_unexpected_directive)
2211         << 1 << getOpenMPDirectiveName(DKind);
2212     break;
2213   default:
2214     break;
2215   }
2216   while (Tok.isNot(tok::annot_pragma_openmp_end))
2217     ConsumeAnyToken();
2218   ConsumeAnyToken();
2219   return nullptr;
2220 }
2221 
2222 /// Parsing of declarative or executable OpenMP directives.
2223 ///
2224 ///       threadprivate-directive:
2225 ///         annot_pragma_openmp 'threadprivate' simple-variable-list
2226 ///         annot_pragma_openmp_end
2227 ///
2228 ///       allocate-directive:
2229 ///         annot_pragma_openmp 'allocate' simple-variable-list
2230 ///         annot_pragma_openmp_end
2231 ///
2232 ///       declare-reduction-directive:
2233 ///         annot_pragma_openmp 'declare' 'reduction' '(' <reduction_id> ':'
2234 ///         <type> {',' <type>} ':' <expression> ')' ['initializer' '('
2235 ///         ('omp_priv' '=' <expression>|<function_call>) ')']
2236 ///         annot_pragma_openmp_end
2237 ///
2238 ///       declare-mapper-directive:
2239 ///         annot_pragma_openmp 'declare' 'mapper' '(' [<mapper-identifer> ':']
2240 ///         <type> <var> ')' [<clause>[[,] <clause>] ... ]
2241 ///         annot_pragma_openmp_end
2242 ///
2243 ///       executable-directive:
2244 ///         annot_pragma_openmp 'parallel' | 'simd' | 'for' | 'sections' |
2245 ///         'section' | 'single' | 'master' | 'critical' [ '(' <name> ')' ] |
2246 ///         'parallel for' | 'parallel sections' | 'parallel master' | 'task' |
2247 ///         'taskyield' | 'barrier' | 'taskwait' | 'flush' | 'ordered' |
2248 ///         'atomic' | 'for simd' | 'parallel for simd' | 'target' | 'target
2249 ///         data' | 'taskgroup' | 'teams' | 'taskloop' | 'taskloop simd' |
2250 ///         'master taskloop' | 'master taskloop simd' | 'parallel master
2251 ///         taskloop' | 'parallel master taskloop simd' | 'distribute' | 'target
2252 ///         enter data' | 'target exit data' | 'target parallel' | 'target
2253 ///         parallel for' | 'target update' | 'distribute parallel for' |
2254 ///         'distribute paralle for simd' | 'distribute simd' | 'target parallel
2255 ///         for simd' | 'target simd' | 'teams distribute' | 'teams distribute
2256 ///         simd' | 'teams distribute parallel for simd' | 'teams distribute
2257 ///         parallel for' | 'target teams' | 'target teams distribute' | 'target
2258 ///         teams distribute parallel for' | 'target teams distribute parallel
2259 ///         for simd' | 'target teams distribute simd' {clause}
2260 ///         annot_pragma_openmp_end
2261 ///
2262 StmtResult
2263 Parser::ParseOpenMPDeclarativeOrExecutableDirective(ParsedStmtContext StmtCtx) {
2264   assert(Tok.is(tok::annot_pragma_openmp) && "Not an OpenMP directive!");
2265   ParsingOpenMPDirectiveRAII DirScope(*this);
2266   ParenBraceBracketBalancer BalancerRAIIObj(*this);
2267   SmallVector<OMPClause *, 5> Clauses;
2268   SmallVector<llvm::PointerIntPair<OMPClause *, 1, bool>,
2269               llvm::omp::Clause_enumSize + 1>
2270       FirstClauses(llvm::omp::Clause_enumSize + 1);
2271   unsigned ScopeFlags = Scope::FnScope | Scope::DeclScope |
2272                         Scope::CompoundStmtScope | Scope::OpenMPDirectiveScope;
2273   SourceLocation Loc = ConsumeAnnotationToken(), EndLoc;
2274   OpenMPDirectiveKind DKind = parseOpenMPDirectiveKind(*this);
2275   OpenMPDirectiveKind CancelRegion = OMPD_unknown;
2276   // Name of critical directive.
2277   DeclarationNameInfo DirName;
2278   StmtResult Directive = StmtError();
2279   bool HasAssociatedStatement = true;
2280 
2281   switch (DKind) {
2282   case OMPD_threadprivate: {
2283     // FIXME: Should this be permitted in C++?
2284     if ((StmtCtx & ParsedStmtContext::AllowDeclarationsInC) ==
2285         ParsedStmtContext()) {
2286       Diag(Tok, diag::err_omp_immediate_directive)
2287           << getOpenMPDirectiveName(DKind) << 0;
2288     }
2289     ConsumeToken();
2290     DeclDirectiveListParserHelper Helper(this, DKind);
2291     if (!ParseOpenMPSimpleVarList(DKind, Helper,
2292                                   /*AllowScopeSpecifier=*/false)) {
2293       skipUntilPragmaOpenMPEnd(DKind);
2294       DeclGroupPtrTy Res = Actions.ActOnOpenMPThreadprivateDirective(
2295           Loc, Helper.getIdentifiers());
2296       Directive = Actions.ActOnDeclStmt(Res, Loc, Tok.getLocation());
2297     }
2298     SkipUntil(tok::annot_pragma_openmp_end);
2299     break;
2300   }
2301   case OMPD_allocate: {
2302     // FIXME: Should this be permitted in C++?
2303     if ((StmtCtx & ParsedStmtContext::AllowDeclarationsInC) ==
2304         ParsedStmtContext()) {
2305       Diag(Tok, diag::err_omp_immediate_directive)
2306           << getOpenMPDirectiveName(DKind) << 0;
2307     }
2308     ConsumeToken();
2309     DeclDirectiveListParserHelper Helper(this, DKind);
2310     if (!ParseOpenMPSimpleVarList(DKind, Helper,
2311                                   /*AllowScopeSpecifier=*/false)) {
2312       SmallVector<OMPClause *, 1> Clauses;
2313       if (Tok.isNot(tok::annot_pragma_openmp_end)) {
2314         SmallVector<llvm::PointerIntPair<OMPClause *, 1, bool>,
2315                     llvm::omp::Clause_enumSize + 1>
2316             FirstClauses(llvm::omp::Clause_enumSize + 1);
2317         while (Tok.isNot(tok::annot_pragma_openmp_end)) {
2318           OpenMPClauseKind CKind =
2319               Tok.isAnnotation() ? OMPC_unknown
2320                                  : getOpenMPClauseKind(PP.getSpelling(Tok));
2321           Actions.StartOpenMPClause(CKind);
2322           OMPClause *Clause = ParseOpenMPClause(
2323               OMPD_allocate, CKind, !FirstClauses[unsigned(CKind)].getInt());
2324           SkipUntil(tok::comma, tok::identifier, tok::annot_pragma_openmp_end,
2325                     StopBeforeMatch);
2326           FirstClauses[unsigned(CKind)].setInt(true);
2327           if (Clause != nullptr)
2328             Clauses.push_back(Clause);
2329           if (Tok.is(tok::annot_pragma_openmp_end)) {
2330             Actions.EndOpenMPClause();
2331             break;
2332           }
2333           // Skip ',' if any.
2334           if (Tok.is(tok::comma))
2335             ConsumeToken();
2336           Actions.EndOpenMPClause();
2337         }
2338         skipUntilPragmaOpenMPEnd(DKind);
2339       }
2340       DeclGroupPtrTy Res = Actions.ActOnOpenMPAllocateDirective(
2341           Loc, Helper.getIdentifiers(), Clauses);
2342       Directive = Actions.ActOnDeclStmt(Res, Loc, Tok.getLocation());
2343     }
2344     SkipUntil(tok::annot_pragma_openmp_end);
2345     break;
2346   }
2347   case OMPD_declare_reduction:
2348     ConsumeToken();
2349     if (DeclGroupPtrTy Res =
2350             ParseOpenMPDeclareReductionDirective(/*AS=*/AS_none)) {
2351       skipUntilPragmaOpenMPEnd(OMPD_declare_reduction);
2352       ConsumeAnyToken();
2353       Directive = Actions.ActOnDeclStmt(Res, Loc, Tok.getLocation());
2354     } else {
2355       SkipUntil(tok::annot_pragma_openmp_end);
2356     }
2357     break;
2358   case OMPD_declare_mapper: {
2359     ConsumeToken();
2360     if (DeclGroupPtrTy Res =
2361             ParseOpenMPDeclareMapperDirective(/*AS=*/AS_none)) {
2362       // Skip the last annot_pragma_openmp_end.
2363       ConsumeAnnotationToken();
2364       Directive = Actions.ActOnDeclStmt(Res, Loc, Tok.getLocation());
2365     } else {
2366       SkipUntil(tok::annot_pragma_openmp_end);
2367     }
2368     break;
2369   }
2370   case OMPD_flush:
2371   case OMPD_depobj:
2372   case OMPD_scan:
2373   case OMPD_taskyield:
2374   case OMPD_barrier:
2375   case OMPD_taskwait:
2376   case OMPD_cancellation_point:
2377   case OMPD_cancel:
2378   case OMPD_target_enter_data:
2379   case OMPD_target_exit_data:
2380   case OMPD_target_update:
2381   case OMPD_interop:
2382     if ((StmtCtx & ParsedStmtContext::AllowStandaloneOpenMPDirectives) ==
2383         ParsedStmtContext()) {
2384       Diag(Tok, diag::err_omp_immediate_directive)
2385           << getOpenMPDirectiveName(DKind) << 0;
2386     }
2387     HasAssociatedStatement = false;
2388     // Fall through for further analysis.
2389     LLVM_FALLTHROUGH;
2390   case OMPD_parallel:
2391   case OMPD_simd:
2392   case OMPD_tile:
2393   case OMPD_for:
2394   case OMPD_for_simd:
2395   case OMPD_sections:
2396   case OMPD_single:
2397   case OMPD_section:
2398   case OMPD_master:
2399   case OMPD_critical:
2400   case OMPD_parallel_for:
2401   case OMPD_parallel_for_simd:
2402   case OMPD_parallel_sections:
2403   case OMPD_parallel_master:
2404   case OMPD_task:
2405   case OMPD_ordered:
2406   case OMPD_atomic:
2407   case OMPD_target:
2408   case OMPD_teams:
2409   case OMPD_taskgroup:
2410   case OMPD_target_data:
2411   case OMPD_target_parallel:
2412   case OMPD_target_parallel_for:
2413   case OMPD_taskloop:
2414   case OMPD_taskloop_simd:
2415   case OMPD_master_taskloop:
2416   case OMPD_master_taskloop_simd:
2417   case OMPD_parallel_master_taskloop:
2418   case OMPD_parallel_master_taskloop_simd:
2419   case OMPD_distribute:
2420   case OMPD_distribute_parallel_for:
2421   case OMPD_distribute_parallel_for_simd:
2422   case OMPD_distribute_simd:
2423   case OMPD_target_parallel_for_simd:
2424   case OMPD_target_simd:
2425   case OMPD_teams_distribute:
2426   case OMPD_teams_distribute_simd:
2427   case OMPD_teams_distribute_parallel_for_simd:
2428   case OMPD_teams_distribute_parallel_for:
2429   case OMPD_target_teams:
2430   case OMPD_target_teams_distribute:
2431   case OMPD_target_teams_distribute_parallel_for:
2432   case OMPD_target_teams_distribute_parallel_for_simd:
2433   case OMPD_target_teams_distribute_simd: {
2434     // Special processing for flush and depobj clauses.
2435     Token ImplicitTok;
2436     bool ImplicitClauseAllowed = false;
2437     if (DKind == OMPD_flush || DKind == OMPD_depobj) {
2438       ImplicitTok = Tok;
2439       ImplicitClauseAllowed = true;
2440     }
2441     ConsumeToken();
2442     // Parse directive name of the 'critical' directive if any.
2443     if (DKind == OMPD_critical) {
2444       BalancedDelimiterTracker T(*this, tok::l_paren,
2445                                  tok::annot_pragma_openmp_end);
2446       if (!T.consumeOpen()) {
2447         if (Tok.isAnyIdentifier()) {
2448           DirName =
2449               DeclarationNameInfo(Tok.getIdentifierInfo(), Tok.getLocation());
2450           ConsumeAnyToken();
2451         } else {
2452           Diag(Tok, diag::err_omp_expected_identifier_for_critical);
2453         }
2454         T.consumeClose();
2455       }
2456     } else if (DKind == OMPD_cancellation_point || DKind == OMPD_cancel) {
2457       CancelRegion = parseOpenMPDirectiveKind(*this);
2458       if (Tok.isNot(tok::annot_pragma_openmp_end))
2459         ConsumeToken();
2460     }
2461 
2462     if (isOpenMPLoopDirective(DKind))
2463       ScopeFlags |= Scope::OpenMPLoopDirectiveScope;
2464     if (isOpenMPSimdDirective(DKind))
2465       ScopeFlags |= Scope::OpenMPSimdDirectiveScope;
2466     ParseScope OMPDirectiveScope(this, ScopeFlags);
2467     Actions.StartOpenMPDSABlock(DKind, DirName, Actions.getCurScope(), Loc);
2468 
2469     while (Tok.isNot(tok::annot_pragma_openmp_end)) {
2470       bool HasImplicitClause = false;
2471       if (ImplicitClauseAllowed && Tok.is(tok::l_paren)) {
2472         HasImplicitClause = true;
2473         // Push copy of the current token back to stream to properly parse
2474         // pseudo-clause OMPFlushClause or OMPDepobjClause.
2475         PP.EnterToken(Tok, /*IsReinject*/ true);
2476         PP.EnterToken(ImplicitTok, /*IsReinject*/ true);
2477         ConsumeAnyToken();
2478       }
2479       OpenMPClauseKind CKind = Tok.isAnnotation()
2480                                    ? OMPC_unknown
2481                                    : getOpenMPClauseKind(PP.getSpelling(Tok));
2482       if (HasImplicitClause) {
2483         assert(CKind == OMPC_unknown && "Must be unknown implicit clause.");
2484         if (DKind == OMPD_flush) {
2485           CKind = OMPC_flush;
2486         } else {
2487           assert(DKind == OMPD_depobj &&
2488                  "Expected flush or depobj directives.");
2489           CKind = OMPC_depobj;
2490         }
2491       }
2492       // No more implicit clauses allowed.
2493       ImplicitClauseAllowed = false;
2494       Actions.StartOpenMPClause(CKind);
2495       HasImplicitClause = false;
2496       OMPClause *Clause = ParseOpenMPClause(
2497           DKind, CKind, !FirstClauses[unsigned(CKind)].getInt());
2498       FirstClauses[unsigned(CKind)].setInt(true);
2499       if (Clause) {
2500         FirstClauses[unsigned(CKind)].setPointer(Clause);
2501         Clauses.push_back(Clause);
2502       }
2503 
2504       // Skip ',' if any.
2505       if (Tok.is(tok::comma))
2506         ConsumeToken();
2507       Actions.EndOpenMPClause();
2508     }
2509     // End location of the directive.
2510     EndLoc = Tok.getLocation();
2511     // Consume final annot_pragma_openmp_end.
2512     ConsumeAnnotationToken();
2513 
2514     // OpenMP [2.13.8, ordered Construct, Syntax]
2515     // If the depend clause is specified, the ordered construct is a stand-alone
2516     // directive.
2517     if (DKind == OMPD_ordered && FirstClauses[unsigned(OMPC_depend)].getInt()) {
2518       if ((StmtCtx & ParsedStmtContext::AllowStandaloneOpenMPDirectives) ==
2519           ParsedStmtContext()) {
2520         Diag(Loc, diag::err_omp_immediate_directive)
2521             << getOpenMPDirectiveName(DKind) << 1
2522             << getOpenMPClauseName(OMPC_depend);
2523       }
2524       HasAssociatedStatement = false;
2525     }
2526 
2527     if (DKind == OMPD_tile && !FirstClauses[unsigned(OMPC_sizes)].getInt()) {
2528       Diag(Loc, diag::err_omp_required_clause)
2529           << getOpenMPDirectiveName(OMPD_tile) << "sizes";
2530     }
2531 
2532     StmtResult AssociatedStmt;
2533     if (HasAssociatedStatement) {
2534       // The body is a block scope like in Lambdas and Blocks.
2535       Actions.ActOnOpenMPRegionStart(DKind, getCurScope());
2536       // FIXME: We create a bogus CompoundStmt scope to hold the contents of
2537       // the captured region. Code elsewhere assumes that any FunctionScopeInfo
2538       // should have at least one compound statement scope within it.
2539       ParsingOpenMPDirectiveRAII NormalScope(*this, /*Value=*/false);
2540       {
2541         Sema::CompoundScopeRAII Scope(Actions);
2542         AssociatedStmt = ParseStatement();
2543 
2544         if (AssociatedStmt.isUsable() && isOpenMPLoopDirective(DKind) &&
2545             getLangOpts().OpenMPIRBuilder)
2546           AssociatedStmt =
2547               Actions.ActOnOpenMPCanonicalLoop(AssociatedStmt.get());
2548       }
2549       AssociatedStmt = Actions.ActOnOpenMPRegionEnd(AssociatedStmt, Clauses);
2550     } else if (DKind == OMPD_target_update || DKind == OMPD_target_enter_data ||
2551                DKind == OMPD_target_exit_data) {
2552       Actions.ActOnOpenMPRegionStart(DKind, getCurScope());
2553       AssociatedStmt = (Sema::CompoundScopeRAII(Actions),
2554                         Actions.ActOnCompoundStmt(Loc, Loc, llvm::None,
2555                                                   /*isStmtExpr=*/false));
2556       AssociatedStmt = Actions.ActOnOpenMPRegionEnd(AssociatedStmt, Clauses);
2557     }
2558     Directive = Actions.ActOnOpenMPExecutableDirective(
2559         DKind, DirName, CancelRegion, Clauses, AssociatedStmt.get(), Loc,
2560         EndLoc);
2561 
2562     // Exit scope.
2563     Actions.EndOpenMPDSABlock(Directive.get());
2564     OMPDirectiveScope.Exit();
2565     break;
2566   }
2567   case OMPD_declare_simd:
2568   case OMPD_declare_target:
2569   case OMPD_end_declare_target:
2570   case OMPD_requires:
2571   case OMPD_begin_declare_variant:
2572   case OMPD_end_declare_variant:
2573   case OMPD_declare_variant:
2574     Diag(Tok, diag::err_omp_unexpected_directive)
2575         << 1 << getOpenMPDirectiveName(DKind);
2576     SkipUntil(tok::annot_pragma_openmp_end);
2577     break;
2578   case OMPD_unknown:
2579   default:
2580     Diag(Tok, diag::err_omp_unknown_directive);
2581     SkipUntil(tok::annot_pragma_openmp_end);
2582     break;
2583   }
2584   return Directive;
2585 }
2586 
2587 // Parses simple list:
2588 //   simple-variable-list:
2589 //         '(' id-expression {, id-expression} ')'
2590 //
2591 bool Parser::ParseOpenMPSimpleVarList(
2592     OpenMPDirectiveKind Kind,
2593     const llvm::function_ref<void(CXXScopeSpec &, DeclarationNameInfo)>
2594         &Callback,
2595     bool AllowScopeSpecifier) {
2596   // Parse '('.
2597   BalancedDelimiterTracker T(*this, tok::l_paren, tok::annot_pragma_openmp_end);
2598   if (T.expectAndConsume(diag::err_expected_lparen_after,
2599                          getOpenMPDirectiveName(Kind).data()))
2600     return true;
2601   bool IsCorrect = true;
2602   bool NoIdentIsFound = true;
2603 
2604   // Read tokens while ')' or annot_pragma_openmp_end is not found.
2605   while (Tok.isNot(tok::r_paren) && Tok.isNot(tok::annot_pragma_openmp_end)) {
2606     CXXScopeSpec SS;
2607     UnqualifiedId Name;
2608     // Read var name.
2609     Token PrevTok = Tok;
2610     NoIdentIsFound = false;
2611 
2612     if (AllowScopeSpecifier && getLangOpts().CPlusPlus &&
2613         ParseOptionalCXXScopeSpecifier(SS, /*ObjectType=*/nullptr,
2614                                        /*ObjectHadErrors=*/false, false)) {
2615       IsCorrect = false;
2616       SkipUntil(tok::comma, tok::r_paren, tok::annot_pragma_openmp_end,
2617                 StopBeforeMatch);
2618     } else if (ParseUnqualifiedId(SS, /*ObjectType=*/nullptr,
2619                                   /*ObjectHadErrors=*/false, false, false,
2620                                   false, false, nullptr, Name)) {
2621       IsCorrect = false;
2622       SkipUntil(tok::comma, tok::r_paren, tok::annot_pragma_openmp_end,
2623                 StopBeforeMatch);
2624     } else if (Tok.isNot(tok::comma) && Tok.isNot(tok::r_paren) &&
2625                Tok.isNot(tok::annot_pragma_openmp_end)) {
2626       IsCorrect = false;
2627       SkipUntil(tok::comma, tok::r_paren, tok::annot_pragma_openmp_end,
2628                 StopBeforeMatch);
2629       Diag(PrevTok.getLocation(), diag::err_expected)
2630           << tok::identifier
2631           << SourceRange(PrevTok.getLocation(), PrevTokLocation);
2632     } else {
2633       Callback(SS, Actions.GetNameFromUnqualifiedId(Name));
2634     }
2635     // Consume ','.
2636     if (Tok.is(tok::comma)) {
2637       ConsumeToken();
2638     }
2639   }
2640 
2641   if (NoIdentIsFound) {
2642     Diag(Tok, diag::err_expected) << tok::identifier;
2643     IsCorrect = false;
2644   }
2645 
2646   // Parse ')'.
2647   IsCorrect = !T.consumeClose() && IsCorrect;
2648 
2649   return !IsCorrect;
2650 }
2651 
2652 OMPClause *Parser::ParseOpenMPSizesClause() {
2653   SourceLocation ClauseNameLoc = ConsumeToken();
2654   SmallVector<Expr *, 4> ValExprs;
2655 
2656   BalancedDelimiterTracker T(*this, tok::l_paren, tok::annot_pragma_openmp_end);
2657   if (T.consumeOpen()) {
2658     Diag(Tok, diag::err_expected) << tok::l_paren;
2659     return nullptr;
2660   }
2661 
2662   while (true) {
2663     ExprResult Val = ParseConstantExpression();
2664     if (!Val.isUsable()) {
2665       T.skipToEnd();
2666       return nullptr;
2667     }
2668 
2669     ValExprs.push_back(Val.get());
2670 
2671     if (Tok.is(tok::r_paren) || Tok.is(tok::annot_pragma_openmp_end))
2672       break;
2673 
2674     ExpectAndConsume(tok::comma);
2675   }
2676 
2677   T.consumeClose();
2678 
2679   return Actions.ActOnOpenMPSizesClause(
2680       ValExprs, ClauseNameLoc, T.getOpenLocation(), T.getCloseLocation());
2681 }
2682 
2683 OMPClause *Parser::ParseOpenMPUsesAllocatorClause(OpenMPDirectiveKind DKind) {
2684   SourceLocation Loc = Tok.getLocation();
2685   ConsumeAnyToken();
2686 
2687   // Parse '('.
2688   BalancedDelimiterTracker T(*this, tok::l_paren, tok::annot_pragma_openmp_end);
2689   if (T.expectAndConsume(diag::err_expected_lparen_after, "uses_allocator"))
2690     return nullptr;
2691   SmallVector<Sema::UsesAllocatorsData, 4> Data;
2692   do {
2693     ExprResult Allocator = ParseCXXIdExpression();
2694     if (Allocator.isInvalid()) {
2695       SkipUntil(tok::comma, tok::r_paren, tok::annot_pragma_openmp_end,
2696                 StopBeforeMatch);
2697       break;
2698     }
2699     Sema::UsesAllocatorsData &D = Data.emplace_back();
2700     D.Allocator = Allocator.get();
2701     if (Tok.is(tok::l_paren)) {
2702       BalancedDelimiterTracker T(*this, tok::l_paren,
2703                                  tok::annot_pragma_openmp_end);
2704       T.consumeOpen();
2705       ExprResult AllocatorTraits = ParseCXXIdExpression();
2706       T.consumeClose();
2707       if (AllocatorTraits.isInvalid()) {
2708         SkipUntil(tok::comma, tok::r_paren, tok::annot_pragma_openmp_end,
2709                   StopBeforeMatch);
2710         break;
2711       }
2712       D.AllocatorTraits = AllocatorTraits.get();
2713       D.LParenLoc = T.getOpenLocation();
2714       D.RParenLoc = T.getCloseLocation();
2715     }
2716     if (Tok.isNot(tok::comma) && Tok.isNot(tok::r_paren))
2717       Diag(Tok, diag::err_omp_expected_punc) << "uses_allocators" << 0;
2718     // Parse ','
2719     if (Tok.is(tok::comma))
2720       ConsumeAnyToken();
2721   } while (Tok.isNot(tok::r_paren) && Tok.isNot(tok::annot_pragma_openmp_end));
2722   T.consumeClose();
2723   return Actions.ActOnOpenMPUsesAllocatorClause(Loc, T.getOpenLocation(),
2724                                                 T.getCloseLocation(), Data);
2725 }
2726 
2727 /// Parsing of OpenMP clauses.
2728 ///
2729 ///    clause:
2730 ///       if-clause | final-clause | num_threads-clause | safelen-clause |
2731 ///       default-clause | private-clause | firstprivate-clause | shared-clause
2732 ///       | linear-clause | aligned-clause | collapse-clause |
2733 ///       lastprivate-clause | reduction-clause | proc_bind-clause |
2734 ///       schedule-clause | copyin-clause | copyprivate-clause | untied-clause |
2735 ///       mergeable-clause | flush-clause | read-clause | write-clause |
2736 ///       update-clause | capture-clause | seq_cst-clause | device-clause |
2737 ///       simdlen-clause | threads-clause | simd-clause | num_teams-clause |
2738 ///       thread_limit-clause | priority-clause | grainsize-clause |
2739 ///       nogroup-clause | num_tasks-clause | hint-clause | to-clause |
2740 ///       from-clause | is_device_ptr-clause | task_reduction-clause |
2741 ///       in_reduction-clause | allocator-clause | allocate-clause |
2742 ///       acq_rel-clause | acquire-clause | release-clause | relaxed-clause |
2743 ///       depobj-clause | destroy-clause | detach-clause | inclusive-clause |
2744 ///       exclusive-clause | uses_allocators-clause | use_device_addr-clause
2745 ///
2746 OMPClause *Parser::ParseOpenMPClause(OpenMPDirectiveKind DKind,
2747                                      OpenMPClauseKind CKind, bool FirstClause) {
2748   OMPClauseKind = CKind;
2749   OMPClause *Clause = nullptr;
2750   bool ErrorFound = false;
2751   bool WrongDirective = false;
2752   // Check if clause is allowed for the given directive.
2753   if (CKind != OMPC_unknown &&
2754       !isAllowedClauseForDirective(DKind, CKind, getLangOpts().OpenMP)) {
2755     Diag(Tok, diag::err_omp_unexpected_clause)
2756         << getOpenMPClauseName(CKind) << getOpenMPDirectiveName(DKind);
2757     ErrorFound = true;
2758     WrongDirective = true;
2759   }
2760 
2761   switch (CKind) {
2762   case OMPC_final:
2763   case OMPC_num_threads:
2764   case OMPC_safelen:
2765   case OMPC_simdlen:
2766   case OMPC_collapse:
2767   case OMPC_ordered:
2768   case OMPC_num_teams:
2769   case OMPC_thread_limit:
2770   case OMPC_priority:
2771   case OMPC_grainsize:
2772   case OMPC_num_tasks:
2773   case OMPC_hint:
2774   case OMPC_allocator:
2775   case OMPC_depobj:
2776   case OMPC_detach:
2777     // OpenMP [2.5, Restrictions]
2778     //  At most one num_threads clause can appear on the directive.
2779     // OpenMP [2.8.1, simd construct, Restrictions]
2780     //  Only one safelen  clause can appear on a simd directive.
2781     //  Only one simdlen  clause can appear on a simd directive.
2782     //  Only one collapse clause can appear on a simd directive.
2783     // OpenMP [2.11.1, task Construct, Restrictions]
2784     //  At most one if clause can appear on the directive.
2785     //  At most one final clause can appear on the directive.
2786     // OpenMP [teams Construct, Restrictions]
2787     //  At most one num_teams clause can appear on the directive.
2788     //  At most one thread_limit clause can appear on the directive.
2789     // OpenMP [2.9.1, task Construct, Restrictions]
2790     // At most one priority clause can appear on the directive.
2791     // OpenMP [2.9.2, taskloop Construct, Restrictions]
2792     // At most one grainsize clause can appear on the directive.
2793     // OpenMP [2.9.2, taskloop Construct, Restrictions]
2794     // At most one num_tasks clause can appear on the directive.
2795     // OpenMP [2.11.3, allocate Directive, Restrictions]
2796     // At most one allocator clause can appear on the directive.
2797     // OpenMP 5.0, 2.10.1 task Construct, Restrictions.
2798     // At most one detach clause can appear on the directive.
2799     if (!FirstClause) {
2800       Diag(Tok, diag::err_omp_more_one_clause)
2801           << getOpenMPDirectiveName(DKind) << getOpenMPClauseName(CKind) << 0;
2802       ErrorFound = true;
2803     }
2804 
2805     if (CKind == OMPC_ordered && PP.LookAhead(/*N=*/0).isNot(tok::l_paren))
2806       Clause = ParseOpenMPClause(CKind, WrongDirective);
2807     else
2808       Clause = ParseOpenMPSingleExprClause(CKind, WrongDirective);
2809     break;
2810   case OMPC_default:
2811   case OMPC_proc_bind:
2812   case OMPC_atomic_default_mem_order:
2813   case OMPC_order:
2814     // OpenMP [2.14.3.1, Restrictions]
2815     //  Only a single default clause may be specified on a parallel, task or
2816     //  teams directive.
2817     // OpenMP [2.5, parallel Construct, Restrictions]
2818     //  At most one proc_bind clause can appear on the directive.
2819     // OpenMP [5.0, Requires directive, Restrictions]
2820     //  At most one atomic_default_mem_order clause can appear
2821     //  on the directive
2822     if (!FirstClause && CKind != OMPC_order) {
2823       Diag(Tok, diag::err_omp_more_one_clause)
2824           << getOpenMPDirectiveName(DKind) << getOpenMPClauseName(CKind) << 0;
2825       ErrorFound = true;
2826     }
2827 
2828     Clause = ParseOpenMPSimpleClause(CKind, WrongDirective);
2829     break;
2830   case OMPC_device:
2831   case OMPC_schedule:
2832   case OMPC_dist_schedule:
2833   case OMPC_defaultmap:
2834     // OpenMP [2.7.1, Restrictions, p. 3]
2835     //  Only one schedule clause can appear on a loop directive.
2836     // OpenMP 4.5 [2.10.4, Restrictions, p. 106]
2837     //  At most one defaultmap clause can appear on the directive.
2838     // OpenMP 5.0 [2.12.5, target construct, Restrictions]
2839     //  At most one device clause can appear on the directive.
2840     if ((getLangOpts().OpenMP < 50 || CKind != OMPC_defaultmap) &&
2841         !FirstClause) {
2842       Diag(Tok, diag::err_omp_more_one_clause)
2843           << getOpenMPDirectiveName(DKind) << getOpenMPClauseName(CKind) << 0;
2844       ErrorFound = true;
2845     }
2846     LLVM_FALLTHROUGH;
2847   case OMPC_if:
2848     Clause = ParseOpenMPSingleExprWithArgClause(DKind, CKind, WrongDirective);
2849     break;
2850   case OMPC_nowait:
2851   case OMPC_untied:
2852   case OMPC_mergeable:
2853   case OMPC_read:
2854   case OMPC_write:
2855   case OMPC_capture:
2856   case OMPC_seq_cst:
2857   case OMPC_acq_rel:
2858   case OMPC_acquire:
2859   case OMPC_release:
2860   case OMPC_relaxed:
2861   case OMPC_threads:
2862   case OMPC_simd:
2863   case OMPC_nogroup:
2864   case OMPC_unified_address:
2865   case OMPC_unified_shared_memory:
2866   case OMPC_reverse_offload:
2867   case OMPC_dynamic_allocators:
2868     // OpenMP [2.7.1, Restrictions, p. 9]
2869     //  Only one ordered clause can appear on a loop directive.
2870     // OpenMP [2.7.1, Restrictions, C/C++, p. 4]
2871     //  Only one nowait clause can appear on a for directive.
2872     // OpenMP [5.0, Requires directive, Restrictions]
2873     //   Each of the requires clauses can appear at most once on the directive.
2874     if (!FirstClause) {
2875       Diag(Tok, diag::err_omp_more_one_clause)
2876           << getOpenMPDirectiveName(DKind) << getOpenMPClauseName(CKind) << 0;
2877       ErrorFound = true;
2878     }
2879 
2880     Clause = ParseOpenMPClause(CKind, WrongDirective);
2881     break;
2882   case OMPC_update:
2883     if (!FirstClause) {
2884       Diag(Tok, diag::err_omp_more_one_clause)
2885           << getOpenMPDirectiveName(DKind) << getOpenMPClauseName(CKind) << 0;
2886       ErrorFound = true;
2887     }
2888 
2889     Clause = (DKind == OMPD_depobj)
2890                  ? ParseOpenMPSimpleClause(CKind, WrongDirective)
2891                  : ParseOpenMPClause(CKind, WrongDirective);
2892     break;
2893   case OMPC_private:
2894   case OMPC_firstprivate:
2895   case OMPC_lastprivate:
2896   case OMPC_shared:
2897   case OMPC_reduction:
2898   case OMPC_task_reduction:
2899   case OMPC_in_reduction:
2900   case OMPC_linear:
2901   case OMPC_aligned:
2902   case OMPC_copyin:
2903   case OMPC_copyprivate:
2904   case OMPC_flush:
2905   case OMPC_depend:
2906   case OMPC_map:
2907   case OMPC_to:
2908   case OMPC_from:
2909   case OMPC_use_device_ptr:
2910   case OMPC_use_device_addr:
2911   case OMPC_is_device_ptr:
2912   case OMPC_allocate:
2913   case OMPC_nontemporal:
2914   case OMPC_inclusive:
2915   case OMPC_exclusive:
2916   case OMPC_affinity:
2917     Clause = ParseOpenMPVarListClause(DKind, CKind, WrongDirective);
2918     break;
2919   case OMPC_sizes:
2920     if (!FirstClause) {
2921       Diag(Tok, diag::err_omp_more_one_clause)
2922           << getOpenMPDirectiveName(DKind) << getOpenMPClauseName(CKind) << 0;
2923       ErrorFound = true;
2924     }
2925 
2926     Clause = ParseOpenMPSizesClause();
2927     break;
2928   case OMPC_uses_allocators:
2929     Clause = ParseOpenMPUsesAllocatorClause(DKind);
2930     break;
2931   case OMPC_destroy:
2932     if (DKind != OMPD_interop) {
2933       if (!FirstClause) {
2934         Diag(Tok, diag::err_omp_more_one_clause)
2935             << getOpenMPDirectiveName(DKind) << getOpenMPClauseName(CKind) << 0;
2936         ErrorFound = true;
2937       }
2938       Clause = ParseOpenMPClause(CKind, WrongDirective);
2939       break;
2940     }
2941     LLVM_FALLTHROUGH;
2942   case OMPC_init:
2943   case OMPC_use:
2944     Clause = ParseOpenMPInteropClause(CKind, WrongDirective);
2945     break;
2946   case OMPC_device_type:
2947   case OMPC_unknown:
2948     skipUntilPragmaOpenMPEnd(DKind);
2949     break;
2950   case OMPC_threadprivate:
2951   case OMPC_uniform:
2952   case OMPC_match:
2953     if (!WrongDirective)
2954       Diag(Tok, diag::err_omp_unexpected_clause)
2955           << getOpenMPClauseName(CKind) << getOpenMPDirectiveName(DKind);
2956     SkipUntil(tok::comma, tok::annot_pragma_openmp_end, StopBeforeMatch);
2957     break;
2958   default:
2959     break;
2960   }
2961   return ErrorFound ? nullptr : Clause;
2962 }
2963 
2964 /// Parses simple expression in parens for single-expression clauses of OpenMP
2965 /// constructs.
2966 /// \param RLoc Returned location of right paren.
2967 ExprResult Parser::ParseOpenMPParensExpr(StringRef ClauseName,
2968                                          SourceLocation &RLoc,
2969                                          bool IsAddressOfOperand) {
2970   BalancedDelimiterTracker T(*this, tok::l_paren, tok::annot_pragma_openmp_end);
2971   if (T.expectAndConsume(diag::err_expected_lparen_after, ClauseName.data()))
2972     return ExprError();
2973 
2974   SourceLocation ELoc = Tok.getLocation();
2975   ExprResult LHS(
2976       ParseCastExpression(AnyCastExpr, IsAddressOfOperand, NotTypeCast));
2977   ExprResult Val(ParseRHSOfBinaryExpression(LHS, prec::Conditional));
2978   Val = Actions.ActOnFinishFullExpr(Val.get(), ELoc, /*DiscardedValue*/ false);
2979 
2980   // Parse ')'.
2981   RLoc = Tok.getLocation();
2982   if (!T.consumeClose())
2983     RLoc = T.getCloseLocation();
2984 
2985   return Val;
2986 }
2987 
2988 /// Parsing of OpenMP clauses with single expressions like 'final',
2989 /// 'collapse', 'safelen', 'num_threads', 'simdlen', 'num_teams',
2990 /// 'thread_limit', 'simdlen', 'priority', 'grainsize', 'num_tasks', 'hint' or
2991 /// 'detach'.
2992 ///
2993 ///    final-clause:
2994 ///      'final' '(' expression ')'
2995 ///
2996 ///    num_threads-clause:
2997 ///      'num_threads' '(' expression ')'
2998 ///
2999 ///    safelen-clause:
3000 ///      'safelen' '(' expression ')'
3001 ///
3002 ///    simdlen-clause:
3003 ///      'simdlen' '(' expression ')'
3004 ///
3005 ///    collapse-clause:
3006 ///      'collapse' '(' expression ')'
3007 ///
3008 ///    priority-clause:
3009 ///      'priority' '(' expression ')'
3010 ///
3011 ///    grainsize-clause:
3012 ///      'grainsize' '(' expression ')'
3013 ///
3014 ///    num_tasks-clause:
3015 ///      'num_tasks' '(' expression ')'
3016 ///
3017 ///    hint-clause:
3018 ///      'hint' '(' expression ')'
3019 ///
3020 ///    allocator-clause:
3021 ///      'allocator' '(' expression ')'
3022 ///
3023 ///    detach-clause:
3024 ///      'detach' '(' event-handler-expression ')'
3025 ///
3026 OMPClause *Parser::ParseOpenMPSingleExprClause(OpenMPClauseKind Kind,
3027                                                bool ParseOnly) {
3028   SourceLocation Loc = ConsumeToken();
3029   SourceLocation LLoc = Tok.getLocation();
3030   SourceLocation RLoc;
3031 
3032   ExprResult Val = ParseOpenMPParensExpr(getOpenMPClauseName(Kind), RLoc);
3033 
3034   if (Val.isInvalid())
3035     return nullptr;
3036 
3037   if (ParseOnly)
3038     return nullptr;
3039   return Actions.ActOnOpenMPSingleExprClause(Kind, Val.get(), Loc, LLoc, RLoc);
3040 }
3041 
3042 /// Parsing of OpenMP clauses that use an interop-var.
3043 ///
3044 /// init-clause:
3045 ///   init([interop-modifier, ]interop-type[[, interop-type] ... ]:interop-var)
3046 ///
3047 /// destroy-clause:
3048 ///   destroy(interop-var)
3049 ///
3050 /// use-clause:
3051 ///   use(interop-var)
3052 ///
3053 /// interop-modifier:
3054 ///   prefer_type(preference-list)
3055 ///
3056 /// preference-list:
3057 ///   foreign-runtime-id [, foreign-runtime-id]...
3058 ///
3059 /// foreign-runtime-id:
3060 ///   <string-literal> | <constant-integral-expression>
3061 ///
3062 /// interop-type:
3063 ///   target | targetsync
3064 ///
3065 OMPClause *Parser::ParseOpenMPInteropClause(OpenMPClauseKind Kind,
3066                                             bool ParseOnly) {
3067   SourceLocation Loc = ConsumeToken();
3068   // Parse '('.
3069   BalancedDelimiterTracker T(*this, tok::l_paren, tok::annot_pragma_openmp_end);
3070   if (T.expectAndConsume(diag::err_expected_lparen_after,
3071                          getOpenMPClauseName(Kind).data()))
3072     return nullptr;
3073 
3074   bool IsTarget = false;
3075   bool IsTargetSync = false;
3076   SmallVector<Expr *, 4> Prefs;
3077 
3078   if (Kind == OMPC_init) {
3079 
3080     // Parse optional interop-modifier.
3081     if (Tok.is(tok::identifier) && PP.getSpelling(Tok) == "prefer_type") {
3082       ConsumeToken();
3083       BalancedDelimiterTracker PT(*this, tok::l_paren,
3084                                   tok::annot_pragma_openmp_end);
3085       if (PT.expectAndConsume(diag::err_expected_lparen_after, "prefer_type"))
3086         return nullptr;
3087 
3088       while (Tok.isNot(tok::r_paren)) {
3089         SourceLocation Loc = Tok.getLocation();
3090         ExprResult LHS = ParseCastExpression(AnyCastExpr);
3091         ExprResult PTExpr = Actions.CorrectDelayedTyposInExpr(
3092             ParseRHSOfBinaryExpression(LHS, prec::Conditional));
3093         PTExpr = Actions.ActOnFinishFullExpr(PTExpr.get(), Loc,
3094                                              /*DiscardedValue=*/false);
3095         if (PTExpr.isUsable())
3096           Prefs.push_back(PTExpr.get());
3097         else
3098           SkipUntil(tok::comma, tok::r_paren, tok::annot_pragma_openmp_end,
3099                     StopBeforeMatch);
3100 
3101         if (Tok.is(tok::comma))
3102           ConsumeToken();
3103       }
3104       PT.consumeClose();
3105     }
3106 
3107     if (!Prefs.empty()) {
3108       if (Tok.is(tok::comma))
3109         ConsumeToken();
3110       else
3111         Diag(Tok, diag::err_omp_expected_punc_after_interop_mod);
3112     }
3113 
3114     // Parse the interop-types.
3115     bool HasError = false;
3116     while (Tok.is(tok::identifier)) {
3117       if (PP.getSpelling(Tok) == "target") {
3118         // OpenMP 5.1 [2.15.1, interop Construct, Restrictions]
3119         // Each interop-type may be specified on an action-clause at most
3120         // once.
3121         if (IsTarget)
3122           Diag(Tok, diag::warn_omp_more_one_interop_type) << "target";
3123         IsTarget = true;
3124       } else if (PP.getSpelling(Tok) == "targetsync") {
3125         if (IsTargetSync)
3126           Diag(Tok, diag::warn_omp_more_one_interop_type) << "targetsync";
3127         IsTargetSync = true;
3128       } else {
3129         HasError = true;
3130         Diag(Tok, diag::err_omp_expected_interop_type);
3131       }
3132       ConsumeToken();
3133 
3134       if (!Tok.is(tok::comma))
3135         break;
3136       ConsumeToken();
3137     }
3138     if (!HasError && !IsTarget && !IsTargetSync)
3139       Diag(Tok, diag::err_omp_expected_interop_type);
3140 
3141     if (Tok.is(tok::colon))
3142       ConsumeToken();
3143     else if (IsTarget || IsTargetSync)
3144       Diag(Tok, diag::warn_pragma_expected_colon) << "interop types";
3145   }
3146 
3147   // Parse the variable.
3148   SourceLocation VarLoc = Tok.getLocation();
3149   ExprResult InteropVarExpr =
3150       Actions.CorrectDelayedTyposInExpr(ParseAssignmentExpression());
3151   if (!InteropVarExpr.isUsable()) {
3152     SkipUntil(tok::comma, tok::r_paren, tok::annot_pragma_openmp_end,
3153               StopBeforeMatch);
3154   }
3155 
3156   // Parse ')'.
3157   SourceLocation RLoc = Tok.getLocation();
3158   if (!T.consumeClose())
3159     RLoc = T.getCloseLocation();
3160 
3161   if (ParseOnly || !InteropVarExpr.isUsable() ||
3162       (Kind == OMPC_init && !IsTarget && !IsTargetSync))
3163     return nullptr;
3164 
3165   if (Kind == OMPC_init)
3166     return Actions.ActOnOpenMPInitClause(InteropVarExpr.get(), Prefs, IsTarget,
3167                                          IsTargetSync, Loc, T.getOpenLocation(),
3168                                          VarLoc, RLoc);
3169   if (Kind == OMPC_use)
3170     return Actions.ActOnOpenMPUseClause(InteropVarExpr.get(), Loc,
3171                                         T.getOpenLocation(), VarLoc, RLoc);
3172 
3173   if (Kind == OMPC_destroy)
3174     return Actions.ActOnOpenMPDestroyClause(InteropVarExpr.get(), Loc,
3175                                             T.getOpenLocation(), VarLoc, RLoc);
3176 
3177   llvm_unreachable("Unexpected interop variable clause.");
3178 }
3179 
3180 /// Parsing of simple OpenMP clauses like 'default' or 'proc_bind'.
3181 ///
3182 ///    default-clause:
3183 ///         'default' '(' 'none' | 'shared' | 'firstprivate' ')'
3184 ///
3185 ///    proc_bind-clause:
3186 ///         'proc_bind' '(' 'master' | 'close' | 'spread' ')'
3187 ///
3188 ///    update-clause:
3189 ///         'update' '(' 'in' | 'out' | 'inout' | 'mutexinoutset' ')'
3190 ///
3191 OMPClause *Parser::ParseOpenMPSimpleClause(OpenMPClauseKind Kind,
3192                                            bool ParseOnly) {
3193   llvm::Optional<SimpleClauseData> Val = parseOpenMPSimpleClause(*this, Kind);
3194   if (!Val || ParseOnly)
3195     return nullptr;
3196   if (getLangOpts().OpenMP < 51 && Kind == OMPC_default &&
3197       static_cast<DefaultKind>(Val.getValue().Type) ==
3198           OMP_DEFAULT_firstprivate) {
3199     Diag(Val.getValue().LOpen, diag::err_omp_invalid_dsa)
3200         << getOpenMPClauseName(OMPC_firstprivate)
3201         << getOpenMPClauseName(OMPC_default) << "5.1";
3202     return nullptr;
3203   }
3204   return Actions.ActOnOpenMPSimpleClause(
3205       Kind, Val.getValue().Type, Val.getValue().TypeLoc, Val.getValue().LOpen,
3206       Val.getValue().Loc, Val.getValue().RLoc);
3207 }
3208 
3209 /// Parsing of OpenMP clauses like 'ordered'.
3210 ///
3211 ///    ordered-clause:
3212 ///         'ordered'
3213 ///
3214 ///    nowait-clause:
3215 ///         'nowait'
3216 ///
3217 ///    untied-clause:
3218 ///         'untied'
3219 ///
3220 ///    mergeable-clause:
3221 ///         'mergeable'
3222 ///
3223 ///    read-clause:
3224 ///         'read'
3225 ///
3226 ///    threads-clause:
3227 ///         'threads'
3228 ///
3229 ///    simd-clause:
3230 ///         'simd'
3231 ///
3232 ///    nogroup-clause:
3233 ///         'nogroup'
3234 ///
3235 OMPClause *Parser::ParseOpenMPClause(OpenMPClauseKind Kind, bool ParseOnly) {
3236   SourceLocation Loc = Tok.getLocation();
3237   ConsumeAnyToken();
3238 
3239   if (ParseOnly)
3240     return nullptr;
3241   return Actions.ActOnOpenMPClause(Kind, Loc, Tok.getLocation());
3242 }
3243 
3244 /// Parsing of OpenMP clauses with single expressions and some additional
3245 /// argument like 'schedule' or 'dist_schedule'.
3246 ///
3247 ///    schedule-clause:
3248 ///      'schedule' '(' [ modifier [ ',' modifier ] ':' ] kind [',' expression ]
3249 ///      ')'
3250 ///
3251 ///    if-clause:
3252 ///      'if' '(' [ directive-name-modifier ':' ] expression ')'
3253 ///
3254 ///    defaultmap:
3255 ///      'defaultmap' '(' modifier [ ':' kind ] ')'
3256 ///
3257 ///    device-clause:
3258 ///      'device' '(' [ device-modifier ':' ] expression ')'
3259 ///
3260 OMPClause *Parser::ParseOpenMPSingleExprWithArgClause(OpenMPDirectiveKind DKind,
3261                                                       OpenMPClauseKind Kind,
3262                                                       bool ParseOnly) {
3263   SourceLocation Loc = ConsumeToken();
3264   SourceLocation DelimLoc;
3265   // Parse '('.
3266   BalancedDelimiterTracker T(*this, tok::l_paren, tok::annot_pragma_openmp_end);
3267   if (T.expectAndConsume(diag::err_expected_lparen_after,
3268                          getOpenMPClauseName(Kind).data()))
3269     return nullptr;
3270 
3271   ExprResult Val;
3272   SmallVector<unsigned, 4> Arg;
3273   SmallVector<SourceLocation, 4> KLoc;
3274   if (Kind == OMPC_schedule) {
3275     enum { Modifier1, Modifier2, ScheduleKind, NumberOfElements };
3276     Arg.resize(NumberOfElements);
3277     KLoc.resize(NumberOfElements);
3278     Arg[Modifier1] = OMPC_SCHEDULE_MODIFIER_unknown;
3279     Arg[Modifier2] = OMPC_SCHEDULE_MODIFIER_unknown;
3280     Arg[ScheduleKind] = OMPC_SCHEDULE_unknown;
3281     unsigned KindModifier = getOpenMPSimpleClauseType(
3282         Kind, Tok.isAnnotation() ? "" : PP.getSpelling(Tok),
3283         getLangOpts().OpenMP);
3284     if (KindModifier > OMPC_SCHEDULE_unknown) {
3285       // Parse 'modifier'
3286       Arg[Modifier1] = KindModifier;
3287       KLoc[Modifier1] = Tok.getLocation();
3288       if (Tok.isNot(tok::r_paren) && Tok.isNot(tok::comma) &&
3289           Tok.isNot(tok::annot_pragma_openmp_end))
3290         ConsumeAnyToken();
3291       if (Tok.is(tok::comma)) {
3292         // Parse ',' 'modifier'
3293         ConsumeAnyToken();
3294         KindModifier = getOpenMPSimpleClauseType(
3295             Kind, Tok.isAnnotation() ? "" : PP.getSpelling(Tok),
3296             getLangOpts().OpenMP);
3297         Arg[Modifier2] = KindModifier > OMPC_SCHEDULE_unknown
3298                              ? KindModifier
3299                              : (unsigned)OMPC_SCHEDULE_unknown;
3300         KLoc[Modifier2] = Tok.getLocation();
3301         if (Tok.isNot(tok::r_paren) && Tok.isNot(tok::comma) &&
3302             Tok.isNot(tok::annot_pragma_openmp_end))
3303           ConsumeAnyToken();
3304       }
3305       // Parse ':'
3306       if (Tok.is(tok::colon))
3307         ConsumeAnyToken();
3308       else
3309         Diag(Tok, diag::warn_pragma_expected_colon) << "schedule modifier";
3310       KindModifier = getOpenMPSimpleClauseType(
3311           Kind, Tok.isAnnotation() ? "" : PP.getSpelling(Tok),
3312           getLangOpts().OpenMP);
3313     }
3314     Arg[ScheduleKind] = KindModifier;
3315     KLoc[ScheduleKind] = Tok.getLocation();
3316     if (Tok.isNot(tok::r_paren) && Tok.isNot(tok::comma) &&
3317         Tok.isNot(tok::annot_pragma_openmp_end))
3318       ConsumeAnyToken();
3319     if ((Arg[ScheduleKind] == OMPC_SCHEDULE_static ||
3320          Arg[ScheduleKind] == OMPC_SCHEDULE_dynamic ||
3321          Arg[ScheduleKind] == OMPC_SCHEDULE_guided) &&
3322         Tok.is(tok::comma))
3323       DelimLoc = ConsumeAnyToken();
3324   } else if (Kind == OMPC_dist_schedule) {
3325     Arg.push_back(getOpenMPSimpleClauseType(
3326         Kind, Tok.isAnnotation() ? "" : PP.getSpelling(Tok),
3327         getLangOpts().OpenMP));
3328     KLoc.push_back(Tok.getLocation());
3329     if (Tok.isNot(tok::r_paren) && Tok.isNot(tok::comma) &&
3330         Tok.isNot(tok::annot_pragma_openmp_end))
3331       ConsumeAnyToken();
3332     if (Arg.back() == OMPC_DIST_SCHEDULE_static && Tok.is(tok::comma))
3333       DelimLoc = ConsumeAnyToken();
3334   } else if (Kind == OMPC_defaultmap) {
3335     // Get a defaultmap modifier
3336     unsigned Modifier = getOpenMPSimpleClauseType(
3337         Kind, Tok.isAnnotation() ? "" : PP.getSpelling(Tok),
3338         getLangOpts().OpenMP);
3339     // Set defaultmap modifier to unknown if it is either scalar, aggregate, or
3340     // pointer
3341     if (Modifier < OMPC_DEFAULTMAP_MODIFIER_unknown)
3342       Modifier = OMPC_DEFAULTMAP_MODIFIER_unknown;
3343     Arg.push_back(Modifier);
3344     KLoc.push_back(Tok.getLocation());
3345     if (Tok.isNot(tok::r_paren) && Tok.isNot(tok::comma) &&
3346         Tok.isNot(tok::annot_pragma_openmp_end))
3347       ConsumeAnyToken();
3348     // Parse ':'
3349     if (Tok.is(tok::colon) || getLangOpts().OpenMP < 50) {
3350       if (Tok.is(tok::colon))
3351         ConsumeAnyToken();
3352       else if (Arg.back() != OMPC_DEFAULTMAP_MODIFIER_unknown)
3353         Diag(Tok, diag::warn_pragma_expected_colon) << "defaultmap modifier";
3354       // Get a defaultmap kind
3355       Arg.push_back(getOpenMPSimpleClauseType(
3356           Kind, Tok.isAnnotation() ? "" : PP.getSpelling(Tok),
3357           getLangOpts().OpenMP));
3358       KLoc.push_back(Tok.getLocation());
3359       if (Tok.isNot(tok::r_paren) && Tok.isNot(tok::comma) &&
3360           Tok.isNot(tok::annot_pragma_openmp_end))
3361         ConsumeAnyToken();
3362     } else {
3363       Arg.push_back(OMPC_DEFAULTMAP_unknown);
3364       KLoc.push_back(SourceLocation());
3365     }
3366   } else if (Kind == OMPC_device) {
3367     // Only target executable directives support extended device construct.
3368     if (isOpenMPTargetExecutionDirective(DKind) && getLangOpts().OpenMP >= 50 &&
3369         NextToken().is(tok::colon)) {
3370       // Parse optional <device modifier> ':'
3371       Arg.push_back(getOpenMPSimpleClauseType(
3372           Kind, Tok.isAnnotation() ? "" : PP.getSpelling(Tok),
3373           getLangOpts().OpenMP));
3374       KLoc.push_back(Tok.getLocation());
3375       ConsumeAnyToken();
3376       // Parse ':'
3377       ConsumeAnyToken();
3378     } else {
3379       Arg.push_back(OMPC_DEVICE_unknown);
3380       KLoc.emplace_back();
3381     }
3382   } else {
3383     assert(Kind == OMPC_if);
3384     KLoc.push_back(Tok.getLocation());
3385     TentativeParsingAction TPA(*this);
3386     auto DK = parseOpenMPDirectiveKind(*this);
3387     Arg.push_back(DK);
3388     if (DK != OMPD_unknown) {
3389       ConsumeToken();
3390       if (Tok.is(tok::colon) && getLangOpts().OpenMP > 40) {
3391         TPA.Commit();
3392         DelimLoc = ConsumeToken();
3393       } else {
3394         TPA.Revert();
3395         Arg.back() = unsigned(OMPD_unknown);
3396       }
3397     } else {
3398       TPA.Revert();
3399     }
3400   }
3401 
3402   bool NeedAnExpression = (Kind == OMPC_schedule && DelimLoc.isValid()) ||
3403                           (Kind == OMPC_dist_schedule && DelimLoc.isValid()) ||
3404                           Kind == OMPC_if || Kind == OMPC_device;
3405   if (NeedAnExpression) {
3406     SourceLocation ELoc = Tok.getLocation();
3407     ExprResult LHS(ParseCastExpression(AnyCastExpr, false, NotTypeCast));
3408     Val = ParseRHSOfBinaryExpression(LHS, prec::Conditional);
3409     Val =
3410         Actions.ActOnFinishFullExpr(Val.get(), ELoc, /*DiscardedValue*/ false);
3411   }
3412 
3413   // Parse ')'.
3414   SourceLocation RLoc = Tok.getLocation();
3415   if (!T.consumeClose())
3416     RLoc = T.getCloseLocation();
3417 
3418   if (NeedAnExpression && Val.isInvalid())
3419     return nullptr;
3420 
3421   if (ParseOnly)
3422     return nullptr;
3423   return Actions.ActOnOpenMPSingleExprWithArgClause(
3424       Kind, Arg, Val.get(), Loc, T.getOpenLocation(), KLoc, DelimLoc, RLoc);
3425 }
3426 
3427 static bool ParseReductionId(Parser &P, CXXScopeSpec &ReductionIdScopeSpec,
3428                              UnqualifiedId &ReductionId) {
3429   if (ReductionIdScopeSpec.isEmpty()) {
3430     auto OOK = OO_None;
3431     switch (P.getCurToken().getKind()) {
3432     case tok::plus:
3433       OOK = OO_Plus;
3434       break;
3435     case tok::minus:
3436       OOK = OO_Minus;
3437       break;
3438     case tok::star:
3439       OOK = OO_Star;
3440       break;
3441     case tok::amp:
3442       OOK = OO_Amp;
3443       break;
3444     case tok::pipe:
3445       OOK = OO_Pipe;
3446       break;
3447     case tok::caret:
3448       OOK = OO_Caret;
3449       break;
3450     case tok::ampamp:
3451       OOK = OO_AmpAmp;
3452       break;
3453     case tok::pipepipe:
3454       OOK = OO_PipePipe;
3455       break;
3456     default:
3457       break;
3458     }
3459     if (OOK != OO_None) {
3460       SourceLocation OpLoc = P.ConsumeToken();
3461       SourceLocation SymbolLocations[] = {OpLoc, OpLoc, SourceLocation()};
3462       ReductionId.setOperatorFunctionId(OpLoc, OOK, SymbolLocations);
3463       return false;
3464     }
3465   }
3466   return P.ParseUnqualifiedId(
3467       ReductionIdScopeSpec, /*ObjectType=*/nullptr,
3468       /*ObjectHadErrors=*/false, /*EnteringContext*/ false,
3469       /*AllowDestructorName*/ false,
3470       /*AllowConstructorName*/ false,
3471       /*AllowDeductionGuide*/ false, nullptr, ReductionId);
3472 }
3473 
3474 /// Checks if the token is a valid map-type-modifier.
3475 /// FIXME: It will return an OpenMPMapClauseKind if that's what it parses.
3476 static OpenMPMapModifierKind isMapModifier(Parser &P) {
3477   Token Tok = P.getCurToken();
3478   if (!Tok.is(tok::identifier))
3479     return OMPC_MAP_MODIFIER_unknown;
3480 
3481   Preprocessor &PP = P.getPreprocessor();
3482   OpenMPMapModifierKind TypeModifier =
3483       static_cast<OpenMPMapModifierKind>(getOpenMPSimpleClauseType(
3484           OMPC_map, PP.getSpelling(Tok), P.getLangOpts().OpenMP));
3485   return TypeModifier;
3486 }
3487 
3488 /// Parse the mapper modifier in map, to, and from clauses.
3489 bool Parser::parseMapperModifier(OpenMPVarListDataTy &Data) {
3490   // Parse '('.
3491   BalancedDelimiterTracker T(*this, tok::l_paren, tok::colon);
3492   if (T.expectAndConsume(diag::err_expected_lparen_after, "mapper")) {
3493     SkipUntil(tok::colon, tok::r_paren, tok::annot_pragma_openmp_end,
3494               StopBeforeMatch);
3495     return true;
3496   }
3497   // Parse mapper-identifier
3498   if (getLangOpts().CPlusPlus)
3499     ParseOptionalCXXScopeSpecifier(Data.ReductionOrMapperIdScopeSpec,
3500                                    /*ObjectType=*/nullptr,
3501                                    /*ObjectHadErrors=*/false,
3502                                    /*EnteringContext=*/false);
3503   if (Tok.isNot(tok::identifier) && Tok.isNot(tok::kw_default)) {
3504     Diag(Tok.getLocation(), diag::err_omp_mapper_illegal_identifier);
3505     SkipUntil(tok::colon, tok::r_paren, tok::annot_pragma_openmp_end,
3506               StopBeforeMatch);
3507     return true;
3508   }
3509   auto &DeclNames = Actions.getASTContext().DeclarationNames;
3510   Data.ReductionOrMapperId = DeclarationNameInfo(
3511       DeclNames.getIdentifier(Tok.getIdentifierInfo()), Tok.getLocation());
3512   ConsumeToken();
3513   // Parse ')'.
3514   return T.consumeClose();
3515 }
3516 
3517 /// Parse map-type-modifiers in map clause.
3518 /// map([ [map-type-modifier[,] [map-type-modifier[,] ...] map-type : ] list)
3519 /// where, map-type-modifier ::= always | close | mapper(mapper-identifier) |
3520 /// present
3521 bool Parser::parseMapTypeModifiers(OpenMPVarListDataTy &Data) {
3522   while (getCurToken().isNot(tok::colon)) {
3523     OpenMPMapModifierKind TypeModifier = isMapModifier(*this);
3524     if (TypeModifier == OMPC_MAP_MODIFIER_always ||
3525         TypeModifier == OMPC_MAP_MODIFIER_close ||
3526         TypeModifier == OMPC_MAP_MODIFIER_present) {
3527       Data.MapTypeModifiers.push_back(TypeModifier);
3528       Data.MapTypeModifiersLoc.push_back(Tok.getLocation());
3529       ConsumeToken();
3530     } else if (TypeModifier == OMPC_MAP_MODIFIER_mapper) {
3531       Data.MapTypeModifiers.push_back(TypeModifier);
3532       Data.MapTypeModifiersLoc.push_back(Tok.getLocation());
3533       ConsumeToken();
3534       if (parseMapperModifier(Data))
3535         return true;
3536     } else {
3537       // For the case of unknown map-type-modifier or a map-type.
3538       // Map-type is followed by a colon; the function returns when it
3539       // encounters a token followed by a colon.
3540       if (Tok.is(tok::comma)) {
3541         Diag(Tok, diag::err_omp_map_type_modifier_missing);
3542         ConsumeToken();
3543         continue;
3544       }
3545       // Potential map-type token as it is followed by a colon.
3546       if (PP.LookAhead(0).is(tok::colon))
3547         return false;
3548       Diag(Tok, diag::err_omp_unknown_map_type_modifier)
3549           << (getLangOpts().OpenMP >= 51 ? 1 : 0);
3550       ConsumeToken();
3551     }
3552     if (getCurToken().is(tok::comma))
3553       ConsumeToken();
3554   }
3555   return false;
3556 }
3557 
3558 /// Checks if the token is a valid map-type.
3559 /// FIXME: It will return an OpenMPMapModifierKind if that's what it parses.
3560 static OpenMPMapClauseKind isMapType(Parser &P) {
3561   Token Tok = P.getCurToken();
3562   // The map-type token can be either an identifier or the C++ delete keyword.
3563   if (!Tok.isOneOf(tok::identifier, tok::kw_delete))
3564     return OMPC_MAP_unknown;
3565   Preprocessor &PP = P.getPreprocessor();
3566   OpenMPMapClauseKind MapType =
3567       static_cast<OpenMPMapClauseKind>(getOpenMPSimpleClauseType(
3568           OMPC_map, PP.getSpelling(Tok), P.getLangOpts().OpenMP));
3569   return MapType;
3570 }
3571 
3572 /// Parse map-type in map clause.
3573 /// map([ [map-type-modifier[,] [map-type-modifier[,] ...] map-type : ] list)
3574 /// where, map-type ::= to | from | tofrom | alloc | release | delete
3575 static void parseMapType(Parser &P, Parser::OpenMPVarListDataTy &Data) {
3576   Token Tok = P.getCurToken();
3577   if (Tok.is(tok::colon)) {
3578     P.Diag(Tok, diag::err_omp_map_type_missing);
3579     return;
3580   }
3581   Data.ExtraModifier = isMapType(P);
3582   if (Data.ExtraModifier == OMPC_MAP_unknown)
3583     P.Diag(Tok, diag::err_omp_unknown_map_type);
3584   P.ConsumeToken();
3585 }
3586 
3587 /// Parses simple expression in parens for single-expression clauses of OpenMP
3588 /// constructs.
3589 ExprResult Parser::ParseOpenMPIteratorsExpr() {
3590   assert(Tok.is(tok::identifier) && PP.getSpelling(Tok) == "iterator" &&
3591          "Expected 'iterator' token.");
3592   SourceLocation IteratorKwLoc = ConsumeToken();
3593 
3594   BalancedDelimiterTracker T(*this, tok::l_paren, tok::annot_pragma_openmp_end);
3595   if (T.expectAndConsume(diag::err_expected_lparen_after, "iterator"))
3596     return ExprError();
3597 
3598   SourceLocation LLoc = T.getOpenLocation();
3599   SmallVector<Sema::OMPIteratorData, 4> Data;
3600   while (Tok.isNot(tok::r_paren) && Tok.isNot(tok::annot_pragma_openmp_end)) {
3601     // Check if the type parsing is required.
3602     ParsedType IteratorType;
3603     if (Tok.isNot(tok::identifier) || NextToken().isNot(tok::equal)) {
3604       // identifier '=' is not found - parse type.
3605       TypeResult TR = ParseTypeName();
3606       if (TR.isInvalid()) {
3607         T.skipToEnd();
3608         return ExprError();
3609       }
3610       IteratorType = TR.get();
3611     }
3612 
3613     // Parse identifier.
3614     IdentifierInfo *II = nullptr;
3615     SourceLocation IdLoc;
3616     if (Tok.is(tok::identifier)) {
3617       II = Tok.getIdentifierInfo();
3618       IdLoc = ConsumeToken();
3619     } else {
3620       Diag(Tok, diag::err_expected_unqualified_id) << 0;
3621     }
3622 
3623     // Parse '='.
3624     SourceLocation AssignLoc;
3625     if (Tok.is(tok::equal))
3626       AssignLoc = ConsumeToken();
3627     else
3628       Diag(Tok, diag::err_omp_expected_equal_in_iterator);
3629 
3630     // Parse range-specification - <begin> ':' <end> [ ':' <step> ]
3631     ColonProtectionRAIIObject ColonRAII(*this);
3632     // Parse <begin>
3633     SourceLocation Loc = Tok.getLocation();
3634     ExprResult LHS = ParseCastExpression(AnyCastExpr);
3635     ExprResult Begin = Actions.CorrectDelayedTyposInExpr(
3636         ParseRHSOfBinaryExpression(LHS, prec::Conditional));
3637     Begin = Actions.ActOnFinishFullExpr(Begin.get(), Loc,
3638                                         /*DiscardedValue=*/false);
3639     // Parse ':'.
3640     SourceLocation ColonLoc;
3641     if (Tok.is(tok::colon))
3642       ColonLoc = ConsumeToken();
3643 
3644     // Parse <end>
3645     Loc = Tok.getLocation();
3646     LHS = ParseCastExpression(AnyCastExpr);
3647     ExprResult End = Actions.CorrectDelayedTyposInExpr(
3648         ParseRHSOfBinaryExpression(LHS, prec::Conditional));
3649     End = Actions.ActOnFinishFullExpr(End.get(), Loc,
3650                                       /*DiscardedValue=*/false);
3651 
3652     SourceLocation SecColonLoc;
3653     ExprResult Step;
3654     // Parse optional step.
3655     if (Tok.is(tok::colon)) {
3656       // Parse ':'
3657       SecColonLoc = ConsumeToken();
3658       // Parse <step>
3659       Loc = Tok.getLocation();
3660       LHS = ParseCastExpression(AnyCastExpr);
3661       Step = Actions.CorrectDelayedTyposInExpr(
3662           ParseRHSOfBinaryExpression(LHS, prec::Conditional));
3663       Step = Actions.ActOnFinishFullExpr(Step.get(), Loc,
3664                                          /*DiscardedValue=*/false);
3665     }
3666 
3667     // Parse ',' or ')'
3668     if (Tok.isNot(tok::comma) && Tok.isNot(tok::r_paren))
3669       Diag(Tok, diag::err_omp_expected_punc_after_iterator);
3670     if (Tok.is(tok::comma))
3671       ConsumeToken();
3672 
3673     Sema::OMPIteratorData &D = Data.emplace_back();
3674     D.DeclIdent = II;
3675     D.DeclIdentLoc = IdLoc;
3676     D.Type = IteratorType;
3677     D.AssignLoc = AssignLoc;
3678     D.ColonLoc = ColonLoc;
3679     D.SecColonLoc = SecColonLoc;
3680     D.Range.Begin = Begin.get();
3681     D.Range.End = End.get();
3682     D.Range.Step = Step.get();
3683   }
3684 
3685   // Parse ')'.
3686   SourceLocation RLoc = Tok.getLocation();
3687   if (!T.consumeClose())
3688     RLoc = T.getCloseLocation();
3689 
3690   return Actions.ActOnOMPIteratorExpr(getCurScope(), IteratorKwLoc, LLoc, RLoc,
3691                                       Data);
3692 }
3693 
3694 /// Parses clauses with list.
3695 bool Parser::ParseOpenMPVarList(OpenMPDirectiveKind DKind,
3696                                 OpenMPClauseKind Kind,
3697                                 SmallVectorImpl<Expr *> &Vars,
3698                                 OpenMPVarListDataTy &Data) {
3699   UnqualifiedId UnqualifiedReductionId;
3700   bool InvalidReductionId = false;
3701   bool IsInvalidMapperModifier = false;
3702 
3703   // Parse '('.
3704   BalancedDelimiterTracker T(*this, tok::l_paren, tok::annot_pragma_openmp_end);
3705   if (T.expectAndConsume(diag::err_expected_lparen_after,
3706                          getOpenMPClauseName(Kind).data()))
3707     return true;
3708 
3709   bool HasIterator = false;
3710   bool NeedRParenForLinear = false;
3711   BalancedDelimiterTracker LinearT(*this, tok::l_paren,
3712                                    tok::annot_pragma_openmp_end);
3713   // Handle reduction-identifier for reduction clause.
3714   if (Kind == OMPC_reduction || Kind == OMPC_task_reduction ||
3715       Kind == OMPC_in_reduction) {
3716     Data.ExtraModifier = OMPC_REDUCTION_unknown;
3717     if (Kind == OMPC_reduction && getLangOpts().OpenMP >= 50 &&
3718         (Tok.is(tok::identifier) || Tok.is(tok::kw_default)) &&
3719         NextToken().is(tok::comma)) {
3720       // Parse optional reduction modifier.
3721       Data.ExtraModifier = getOpenMPSimpleClauseType(Kind, PP.getSpelling(Tok),
3722                                                      getLangOpts().OpenMP);
3723       Data.ExtraModifierLoc = Tok.getLocation();
3724       ConsumeToken();
3725       assert(Tok.is(tok::comma) && "Expected comma.");
3726       (void)ConsumeToken();
3727     }
3728     ColonProtectionRAIIObject ColonRAII(*this);
3729     if (getLangOpts().CPlusPlus)
3730       ParseOptionalCXXScopeSpecifier(Data.ReductionOrMapperIdScopeSpec,
3731                                      /*ObjectType=*/nullptr,
3732                                      /*ObjectHadErrors=*/false,
3733                                      /*EnteringContext=*/false);
3734     InvalidReductionId = ParseReductionId(
3735         *this, Data.ReductionOrMapperIdScopeSpec, UnqualifiedReductionId);
3736     if (InvalidReductionId) {
3737       SkipUntil(tok::colon, tok::r_paren, tok::annot_pragma_openmp_end,
3738                 StopBeforeMatch);
3739     }
3740     if (Tok.is(tok::colon))
3741       Data.ColonLoc = ConsumeToken();
3742     else
3743       Diag(Tok, diag::warn_pragma_expected_colon) << "reduction identifier";
3744     if (!InvalidReductionId)
3745       Data.ReductionOrMapperId =
3746           Actions.GetNameFromUnqualifiedId(UnqualifiedReductionId);
3747   } else if (Kind == OMPC_depend) {
3748     if (getLangOpts().OpenMP >= 50) {
3749       if (Tok.is(tok::identifier) && PP.getSpelling(Tok) == "iterator") {
3750         // Handle optional dependence modifier.
3751         // iterator(iterators-definition)
3752         // where iterators-definition is iterator-specifier [,
3753         // iterators-definition ]
3754         // where iterator-specifier is [ iterator-type ] identifier =
3755         // range-specification
3756         HasIterator = true;
3757         EnterScope(Scope::OpenMPDirectiveScope | Scope::DeclScope);
3758         ExprResult IteratorRes = ParseOpenMPIteratorsExpr();
3759         Data.DepModOrTailExpr = IteratorRes.get();
3760         // Parse ','
3761         ExpectAndConsume(tok::comma);
3762       }
3763     }
3764     // Handle dependency type for depend clause.
3765     ColonProtectionRAIIObject ColonRAII(*this);
3766     Data.ExtraModifier = getOpenMPSimpleClauseType(
3767         Kind, Tok.is(tok::identifier) ? PP.getSpelling(Tok) : "",
3768         getLangOpts().OpenMP);
3769     Data.ExtraModifierLoc = Tok.getLocation();
3770     if (Data.ExtraModifier == OMPC_DEPEND_unknown) {
3771       SkipUntil(tok::colon, tok::r_paren, tok::annot_pragma_openmp_end,
3772                 StopBeforeMatch);
3773     } else {
3774       ConsumeToken();
3775       // Special processing for depend(source) clause.
3776       if (DKind == OMPD_ordered && Data.ExtraModifier == OMPC_DEPEND_source) {
3777         // Parse ')'.
3778         T.consumeClose();
3779         return false;
3780       }
3781     }
3782     if (Tok.is(tok::colon)) {
3783       Data.ColonLoc = ConsumeToken();
3784     } else {
3785       Diag(Tok, DKind == OMPD_ordered ? diag::warn_pragma_expected_colon_r_paren
3786                                       : diag::warn_pragma_expected_colon)
3787           << "dependency type";
3788     }
3789   } else if (Kind == OMPC_linear) {
3790     // Try to parse modifier if any.
3791     Data.ExtraModifier = OMPC_LINEAR_val;
3792     if (Tok.is(tok::identifier) && PP.LookAhead(0).is(tok::l_paren)) {
3793       Data.ExtraModifier = getOpenMPSimpleClauseType(Kind, PP.getSpelling(Tok),
3794                                                      getLangOpts().OpenMP);
3795       Data.ExtraModifierLoc = ConsumeToken();
3796       LinearT.consumeOpen();
3797       NeedRParenForLinear = true;
3798     }
3799   } else if (Kind == OMPC_lastprivate) {
3800     // Try to parse modifier if any.
3801     Data.ExtraModifier = OMPC_LASTPRIVATE_unknown;
3802     // Conditional modifier allowed only in OpenMP 5.0 and not supported in
3803     // distribute and taskloop based directives.
3804     if ((getLangOpts().OpenMP >= 50 && !isOpenMPDistributeDirective(DKind) &&
3805          !isOpenMPTaskLoopDirective(DKind)) &&
3806         Tok.is(tok::identifier) && PP.LookAhead(0).is(tok::colon)) {
3807       Data.ExtraModifier = getOpenMPSimpleClauseType(Kind, PP.getSpelling(Tok),
3808                                                      getLangOpts().OpenMP);
3809       Data.ExtraModifierLoc = Tok.getLocation();
3810       ConsumeToken();
3811       assert(Tok.is(tok::colon) && "Expected colon.");
3812       Data.ColonLoc = ConsumeToken();
3813     }
3814   } else if (Kind == OMPC_map) {
3815     // Handle map type for map clause.
3816     ColonProtectionRAIIObject ColonRAII(*this);
3817 
3818     // The first identifier may be a list item, a map-type or a
3819     // map-type-modifier. The map-type can also be delete which has the same
3820     // spelling of the C++ delete keyword.
3821     Data.ExtraModifier = OMPC_MAP_unknown;
3822     Data.ExtraModifierLoc = Tok.getLocation();
3823 
3824     // Check for presence of a colon in the map clause.
3825     TentativeParsingAction TPA(*this);
3826     bool ColonPresent = false;
3827     if (SkipUntil(tok::colon, tok::r_paren, tok::annot_pragma_openmp_end,
3828                   StopBeforeMatch)) {
3829       if (Tok.is(tok::colon))
3830         ColonPresent = true;
3831     }
3832     TPA.Revert();
3833     // Only parse map-type-modifier[s] and map-type if a colon is present in
3834     // the map clause.
3835     if (ColonPresent) {
3836       IsInvalidMapperModifier = parseMapTypeModifiers(Data);
3837       if (!IsInvalidMapperModifier)
3838         parseMapType(*this, Data);
3839       else
3840         SkipUntil(tok::colon, tok::annot_pragma_openmp_end, StopBeforeMatch);
3841     }
3842     if (Data.ExtraModifier == OMPC_MAP_unknown) {
3843       Data.ExtraModifier = OMPC_MAP_tofrom;
3844       Data.IsMapTypeImplicit = true;
3845     }
3846 
3847     if (Tok.is(tok::colon))
3848       Data.ColonLoc = ConsumeToken();
3849   } else if (Kind == OMPC_to || Kind == OMPC_from) {
3850     while (Tok.is(tok::identifier)) {
3851       auto Modifier =
3852           static_cast<OpenMPMotionModifierKind>(getOpenMPSimpleClauseType(
3853               Kind, PP.getSpelling(Tok), getLangOpts().OpenMP));
3854       if (Modifier == OMPC_MOTION_MODIFIER_unknown)
3855         break;
3856       Data.MotionModifiers.push_back(Modifier);
3857       Data.MotionModifiersLoc.push_back(Tok.getLocation());
3858       ConsumeToken();
3859       if (Modifier == OMPC_MOTION_MODIFIER_mapper) {
3860         IsInvalidMapperModifier = parseMapperModifier(Data);
3861         if (IsInvalidMapperModifier)
3862           break;
3863       }
3864       // OpenMP < 5.1 doesn't permit a ',' or additional modifiers.
3865       if (getLangOpts().OpenMP < 51)
3866         break;
3867       // OpenMP 5.1 accepts an optional ',' even if the next character is ':'.
3868       // TODO: Is that intentional?
3869       if (Tok.is(tok::comma))
3870         ConsumeToken();
3871     }
3872     if (!Data.MotionModifiers.empty() && Tok.isNot(tok::colon)) {
3873       if (!IsInvalidMapperModifier) {
3874         if (getLangOpts().OpenMP < 51)
3875           Diag(Tok, diag::warn_pragma_expected_colon) << ")";
3876         else
3877           Diag(Tok, diag::warn_pragma_expected_colon) << "motion modifier";
3878       }
3879       SkipUntil(tok::colon, tok::r_paren, tok::annot_pragma_openmp_end,
3880                 StopBeforeMatch);
3881     }
3882     // OpenMP 5.1 permits a ':' even without a preceding modifier.  TODO: Is
3883     // that intentional?
3884     if ((!Data.MotionModifiers.empty() || getLangOpts().OpenMP >= 51) &&
3885         Tok.is(tok::colon))
3886       Data.ColonLoc = ConsumeToken();
3887   } else if (Kind == OMPC_allocate ||
3888              (Kind == OMPC_affinity && Tok.is(tok::identifier) &&
3889               PP.getSpelling(Tok) == "iterator")) {
3890     // Handle optional allocator expression followed by colon delimiter.
3891     ColonProtectionRAIIObject ColonRAII(*this);
3892     TentativeParsingAction TPA(*this);
3893     // OpenMP 5.0, 2.10.1, task Construct.
3894     // where aff-modifier is one of the following:
3895     // iterator(iterators-definition)
3896     ExprResult Tail;
3897     if (Kind == OMPC_allocate) {
3898       Tail = ParseAssignmentExpression();
3899     } else {
3900       HasIterator = true;
3901       EnterScope(Scope::OpenMPDirectiveScope | Scope::DeclScope);
3902       Tail = ParseOpenMPIteratorsExpr();
3903     }
3904     Tail = Actions.CorrectDelayedTyposInExpr(Tail);
3905     Tail = Actions.ActOnFinishFullExpr(Tail.get(), T.getOpenLocation(),
3906                                        /*DiscardedValue=*/false);
3907     if (Tail.isUsable()) {
3908       if (Tok.is(tok::colon)) {
3909         Data.DepModOrTailExpr = Tail.get();
3910         Data.ColonLoc = ConsumeToken();
3911         TPA.Commit();
3912       } else {
3913         // Colon not found, parse only list of variables.
3914         TPA.Revert();
3915       }
3916     } else {
3917       // Parsing was unsuccessfull, revert and skip to the end of clause or
3918       // directive.
3919       TPA.Revert();
3920       SkipUntil(tok::comma, tok::r_paren, tok::annot_pragma_openmp_end,
3921                 StopBeforeMatch);
3922     }
3923   }
3924 
3925   bool IsComma =
3926       (Kind != OMPC_reduction && Kind != OMPC_task_reduction &&
3927        Kind != OMPC_in_reduction && Kind != OMPC_depend && Kind != OMPC_map) ||
3928       (Kind == OMPC_reduction && !InvalidReductionId) ||
3929       (Kind == OMPC_map && Data.ExtraModifier != OMPC_MAP_unknown) ||
3930       (Kind == OMPC_depend && Data.ExtraModifier != OMPC_DEPEND_unknown);
3931   const bool MayHaveTail = (Kind == OMPC_linear || Kind == OMPC_aligned);
3932   while (IsComma || (Tok.isNot(tok::r_paren) && Tok.isNot(tok::colon) &&
3933                      Tok.isNot(tok::annot_pragma_openmp_end))) {
3934     ParseScope OMPListScope(this, Scope::OpenMPDirectiveScope);
3935     ColonProtectionRAIIObject ColonRAII(*this, MayHaveTail);
3936     // Parse variable
3937     ExprResult VarExpr =
3938         Actions.CorrectDelayedTyposInExpr(ParseAssignmentExpression());
3939     if (VarExpr.isUsable()) {
3940       Vars.push_back(VarExpr.get());
3941     } else {
3942       SkipUntil(tok::comma, tok::r_paren, tok::annot_pragma_openmp_end,
3943                 StopBeforeMatch);
3944     }
3945     // Skip ',' if any
3946     IsComma = Tok.is(tok::comma);
3947     if (IsComma)
3948       ConsumeToken();
3949     else if (Tok.isNot(tok::r_paren) &&
3950              Tok.isNot(tok::annot_pragma_openmp_end) &&
3951              (!MayHaveTail || Tok.isNot(tok::colon)))
3952       Diag(Tok, diag::err_omp_expected_punc)
3953           << ((Kind == OMPC_flush) ? getOpenMPDirectiveName(OMPD_flush)
3954                                    : getOpenMPClauseName(Kind))
3955           << (Kind == OMPC_flush);
3956   }
3957 
3958   // Parse ')' for linear clause with modifier.
3959   if (NeedRParenForLinear)
3960     LinearT.consumeClose();
3961 
3962   // Parse ':' linear-step (or ':' alignment).
3963   const bool MustHaveTail = MayHaveTail && Tok.is(tok::colon);
3964   if (MustHaveTail) {
3965     Data.ColonLoc = Tok.getLocation();
3966     SourceLocation ELoc = ConsumeToken();
3967     ExprResult Tail = ParseAssignmentExpression();
3968     Tail =
3969         Actions.ActOnFinishFullExpr(Tail.get(), ELoc, /*DiscardedValue*/ false);
3970     if (Tail.isUsable())
3971       Data.DepModOrTailExpr = Tail.get();
3972     else
3973       SkipUntil(tok::comma, tok::r_paren, tok::annot_pragma_openmp_end,
3974                 StopBeforeMatch);
3975   }
3976 
3977   // Parse ')'.
3978   Data.RLoc = Tok.getLocation();
3979   if (!T.consumeClose())
3980     Data.RLoc = T.getCloseLocation();
3981   // Exit from scope when the iterator is used in depend clause.
3982   if (HasIterator)
3983     ExitScope();
3984   return (Kind != OMPC_depend && Kind != OMPC_map && Vars.empty()) ||
3985          (MustHaveTail && !Data.DepModOrTailExpr) || InvalidReductionId ||
3986          IsInvalidMapperModifier;
3987 }
3988 
3989 /// Parsing of OpenMP clause 'private', 'firstprivate', 'lastprivate',
3990 /// 'shared', 'copyin', 'copyprivate', 'flush', 'reduction', 'task_reduction',
3991 /// 'in_reduction', 'nontemporal', 'exclusive' or 'inclusive'.
3992 ///
3993 ///    private-clause:
3994 ///       'private' '(' list ')'
3995 ///    firstprivate-clause:
3996 ///       'firstprivate' '(' list ')'
3997 ///    lastprivate-clause:
3998 ///       'lastprivate' '(' list ')'
3999 ///    shared-clause:
4000 ///       'shared' '(' list ')'
4001 ///    linear-clause:
4002 ///       'linear' '(' linear-list [ ':' linear-step ] ')'
4003 ///    aligned-clause:
4004 ///       'aligned' '(' list [ ':' alignment ] ')'
4005 ///    reduction-clause:
4006 ///       'reduction' '(' [ modifier ',' ] reduction-identifier ':' list ')'
4007 ///    task_reduction-clause:
4008 ///       'task_reduction' '(' reduction-identifier ':' list ')'
4009 ///    in_reduction-clause:
4010 ///       'in_reduction' '(' reduction-identifier ':' list ')'
4011 ///    copyprivate-clause:
4012 ///       'copyprivate' '(' list ')'
4013 ///    flush-clause:
4014 ///       'flush' '(' list ')'
4015 ///    depend-clause:
4016 ///       'depend' '(' in | out | inout : list | source ')'
4017 ///    map-clause:
4018 ///       'map' '(' [ [ always [,] ] [ close [,] ]
4019 ///          [ mapper '(' mapper-identifier ')' [,] ]
4020 ///          to | from | tofrom | alloc | release | delete ':' ] list ')';
4021 ///    to-clause:
4022 ///       'to' '(' [ mapper '(' mapper-identifier ')' ':' ] list ')'
4023 ///    from-clause:
4024 ///       'from' '(' [ mapper '(' mapper-identifier ')' ':' ] list ')'
4025 ///    use_device_ptr-clause:
4026 ///       'use_device_ptr' '(' list ')'
4027 ///    use_device_addr-clause:
4028 ///       'use_device_addr' '(' list ')'
4029 ///    is_device_ptr-clause:
4030 ///       'is_device_ptr' '(' list ')'
4031 ///    allocate-clause:
4032 ///       'allocate' '(' [ allocator ':' ] list ')'
4033 ///    nontemporal-clause:
4034 ///       'nontemporal' '(' list ')'
4035 ///    inclusive-clause:
4036 ///       'inclusive' '(' list ')'
4037 ///    exclusive-clause:
4038 ///       'exclusive' '(' list ')'
4039 ///
4040 /// For 'linear' clause linear-list may have the following forms:
4041 ///  list
4042 ///  modifier(list)
4043 /// where modifier is 'val' (C) or 'ref', 'val' or 'uval'(C++).
4044 OMPClause *Parser::ParseOpenMPVarListClause(OpenMPDirectiveKind DKind,
4045                                             OpenMPClauseKind Kind,
4046                                             bool ParseOnly) {
4047   SourceLocation Loc = Tok.getLocation();
4048   SourceLocation LOpen = ConsumeToken();
4049   SmallVector<Expr *, 4> Vars;
4050   OpenMPVarListDataTy Data;
4051 
4052   if (ParseOpenMPVarList(DKind, Kind, Vars, Data))
4053     return nullptr;
4054 
4055   if (ParseOnly)
4056     return nullptr;
4057   OMPVarListLocTy Locs(Loc, LOpen, Data.RLoc);
4058   return Actions.ActOnOpenMPVarListClause(
4059       Kind, Vars, Data.DepModOrTailExpr, Locs, Data.ColonLoc,
4060       Data.ReductionOrMapperIdScopeSpec, Data.ReductionOrMapperId,
4061       Data.ExtraModifier, Data.MapTypeModifiers, Data.MapTypeModifiersLoc,
4062       Data.IsMapTypeImplicit, Data.ExtraModifierLoc, Data.MotionModifiers,
4063       Data.MotionModifiersLoc);
4064 }
4065