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     while (Tok.isNot(tok::eof) && Tok.isNot(tok::r_brace)) {
2119       if (Tok.isAnnotation() && Tok.is(tok::annot_pragma_openmp)) {
2120         TentativeParsingAction TPA(*this);
2121         ConsumeAnnotationToken();
2122         DKind = parseOpenMPDirectiveKind(*this);
2123         if (DKind != OMPD_end_declare_target)
2124           TPA.Revert();
2125         else
2126           TPA.Commit();
2127       }
2128       if (DKind == OMPD_end_declare_target)
2129         break;
2130       DeclGroupPtrTy Ptr;
2131       // Here we expect to see some function declaration.
2132       if (AS == AS_none) {
2133         assert(TagType == DeclSpec::TST_unspecified);
2134         MaybeParseCXX11Attributes(Attrs);
2135         ParsingDeclSpec PDS(*this);
2136         Ptr = ParseExternalDeclaration(Attrs, &PDS);
2137       } else {
2138         Ptr =
2139             ParseCXXClassMemberDeclarationWithPragmas(AS, Attrs, TagType, Tag);
2140       }
2141       if (Ptr) {
2142         DeclGroupRef Ref = Ptr.get();
2143         Decls.append(Ref.begin(), Ref.end());
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   case OMPD_dispatch:
2211   case OMPD_masked:
2212     Diag(Tok, diag::err_omp_unexpected_directive)
2213         << 1 << getOpenMPDirectiveName(DKind);
2214     break;
2215   default:
2216     break;
2217   }
2218   while (Tok.isNot(tok::annot_pragma_openmp_end))
2219     ConsumeAnyToken();
2220   ConsumeAnyToken();
2221   return nullptr;
2222 }
2223 
2224 /// Parsing of declarative or executable OpenMP directives.
2225 ///
2226 ///       threadprivate-directive:
2227 ///         annot_pragma_openmp 'threadprivate' simple-variable-list
2228 ///         annot_pragma_openmp_end
2229 ///
2230 ///       allocate-directive:
2231 ///         annot_pragma_openmp 'allocate' simple-variable-list
2232 ///         annot_pragma_openmp_end
2233 ///
2234 ///       declare-reduction-directive:
2235 ///         annot_pragma_openmp 'declare' 'reduction' '(' <reduction_id> ':'
2236 ///         <type> {',' <type>} ':' <expression> ')' ['initializer' '('
2237 ///         ('omp_priv' '=' <expression>|<function_call>) ')']
2238 ///         annot_pragma_openmp_end
2239 ///
2240 ///       declare-mapper-directive:
2241 ///         annot_pragma_openmp 'declare' 'mapper' '(' [<mapper-identifer> ':']
2242 ///         <type> <var> ')' [<clause>[[,] <clause>] ... ]
2243 ///         annot_pragma_openmp_end
2244 ///
2245 ///       executable-directive:
2246 ///         annot_pragma_openmp 'parallel' | 'simd' | 'for' | 'sections' |
2247 ///         'section' | 'single' | 'master' | 'critical' [ '(' <name> ')' ] |
2248 ///         'parallel for' | 'parallel sections' | 'parallel master' | 'task' |
2249 ///         'taskyield' | 'barrier' | 'taskwait' | 'flush' | 'ordered' |
2250 ///         'atomic' | 'for simd' | 'parallel for simd' | 'target' | 'target
2251 ///         data' | 'taskgroup' | 'teams' | 'taskloop' | 'taskloop simd' |
2252 ///         'master taskloop' | 'master taskloop simd' | 'parallel master
2253 ///         taskloop' | 'parallel master taskloop simd' | 'distribute' | 'target
2254 ///         enter data' | 'target exit data' | 'target parallel' | 'target
2255 ///         parallel for' | 'target update' | 'distribute parallel for' |
2256 ///         'distribute paralle for simd' | 'distribute simd' | 'target parallel
2257 ///         for simd' | 'target simd' | 'teams distribute' | 'teams distribute
2258 ///         simd' | 'teams distribute parallel for simd' | 'teams distribute
2259 ///         parallel for' | 'target teams' | 'target teams distribute' | 'target
2260 ///         teams distribute parallel for' | 'target teams distribute parallel
2261 ///         for simd' | 'target teams distribute simd' | 'masked' {clause}
2262 ///         annot_pragma_openmp_end
2263 ///
2264 StmtResult
2265 Parser::ParseOpenMPDeclarativeOrExecutableDirective(ParsedStmtContext StmtCtx) {
2266   assert(Tok.is(tok::annot_pragma_openmp) && "Not an OpenMP directive!");
2267   ParsingOpenMPDirectiveRAII DirScope(*this);
2268   ParenBraceBracketBalancer BalancerRAIIObj(*this);
2269   SmallVector<OMPClause *, 5> Clauses;
2270   SmallVector<llvm::PointerIntPair<OMPClause *, 1, bool>,
2271               llvm::omp::Clause_enumSize + 1>
2272       FirstClauses(llvm::omp::Clause_enumSize + 1);
2273   unsigned ScopeFlags = Scope::FnScope | Scope::DeclScope |
2274                         Scope::CompoundStmtScope | Scope::OpenMPDirectiveScope;
2275   SourceLocation Loc = ConsumeAnnotationToken(), EndLoc;
2276   OpenMPDirectiveKind DKind = parseOpenMPDirectiveKind(*this);
2277   OpenMPDirectiveKind CancelRegion = OMPD_unknown;
2278   // Name of critical directive.
2279   DeclarationNameInfo DirName;
2280   StmtResult Directive = StmtError();
2281   bool HasAssociatedStatement = true;
2282 
2283   switch (DKind) {
2284   case OMPD_threadprivate: {
2285     // FIXME: Should this be permitted in C++?
2286     if ((StmtCtx & ParsedStmtContext::AllowDeclarationsInC) ==
2287         ParsedStmtContext()) {
2288       Diag(Tok, diag::err_omp_immediate_directive)
2289           << getOpenMPDirectiveName(DKind) << 0;
2290     }
2291     ConsumeToken();
2292     DeclDirectiveListParserHelper Helper(this, DKind);
2293     if (!ParseOpenMPSimpleVarList(DKind, Helper,
2294                                   /*AllowScopeSpecifier=*/false)) {
2295       skipUntilPragmaOpenMPEnd(DKind);
2296       DeclGroupPtrTy Res = Actions.ActOnOpenMPThreadprivateDirective(
2297           Loc, Helper.getIdentifiers());
2298       Directive = Actions.ActOnDeclStmt(Res, Loc, Tok.getLocation());
2299     }
2300     SkipUntil(tok::annot_pragma_openmp_end);
2301     break;
2302   }
2303   case OMPD_allocate: {
2304     // FIXME: Should this be permitted in C++?
2305     if ((StmtCtx & ParsedStmtContext::AllowDeclarationsInC) ==
2306         ParsedStmtContext()) {
2307       Diag(Tok, diag::err_omp_immediate_directive)
2308           << getOpenMPDirectiveName(DKind) << 0;
2309     }
2310     ConsumeToken();
2311     DeclDirectiveListParserHelper Helper(this, DKind);
2312     if (!ParseOpenMPSimpleVarList(DKind, Helper,
2313                                   /*AllowScopeSpecifier=*/false)) {
2314       SmallVector<OMPClause *, 1> Clauses;
2315       if (Tok.isNot(tok::annot_pragma_openmp_end)) {
2316         SmallVector<llvm::PointerIntPair<OMPClause *, 1, bool>,
2317                     llvm::omp::Clause_enumSize + 1>
2318             FirstClauses(llvm::omp::Clause_enumSize + 1);
2319         while (Tok.isNot(tok::annot_pragma_openmp_end)) {
2320           OpenMPClauseKind CKind =
2321               Tok.isAnnotation() ? OMPC_unknown
2322                                  : getOpenMPClauseKind(PP.getSpelling(Tok));
2323           Actions.StartOpenMPClause(CKind);
2324           OMPClause *Clause = ParseOpenMPClause(
2325               OMPD_allocate, CKind, !FirstClauses[unsigned(CKind)].getInt());
2326           SkipUntil(tok::comma, tok::identifier, tok::annot_pragma_openmp_end,
2327                     StopBeforeMatch);
2328           FirstClauses[unsigned(CKind)].setInt(true);
2329           if (Clause != nullptr)
2330             Clauses.push_back(Clause);
2331           if (Tok.is(tok::annot_pragma_openmp_end)) {
2332             Actions.EndOpenMPClause();
2333             break;
2334           }
2335           // Skip ',' if any.
2336           if (Tok.is(tok::comma))
2337             ConsumeToken();
2338           Actions.EndOpenMPClause();
2339         }
2340         skipUntilPragmaOpenMPEnd(DKind);
2341       }
2342       DeclGroupPtrTy Res = Actions.ActOnOpenMPAllocateDirective(
2343           Loc, Helper.getIdentifiers(), Clauses);
2344       Directive = Actions.ActOnDeclStmt(Res, Loc, Tok.getLocation());
2345     }
2346     SkipUntil(tok::annot_pragma_openmp_end);
2347     break;
2348   }
2349   case OMPD_declare_reduction:
2350     ConsumeToken();
2351     if (DeclGroupPtrTy Res =
2352             ParseOpenMPDeclareReductionDirective(/*AS=*/AS_none)) {
2353       skipUntilPragmaOpenMPEnd(OMPD_declare_reduction);
2354       ConsumeAnyToken();
2355       Directive = Actions.ActOnDeclStmt(Res, Loc, Tok.getLocation());
2356     } else {
2357       SkipUntil(tok::annot_pragma_openmp_end);
2358     }
2359     break;
2360   case OMPD_declare_mapper: {
2361     ConsumeToken();
2362     if (DeclGroupPtrTy Res =
2363             ParseOpenMPDeclareMapperDirective(/*AS=*/AS_none)) {
2364       // Skip the last annot_pragma_openmp_end.
2365       ConsumeAnnotationToken();
2366       Directive = Actions.ActOnDeclStmt(Res, Loc, Tok.getLocation());
2367     } else {
2368       SkipUntil(tok::annot_pragma_openmp_end);
2369     }
2370     break;
2371   }
2372   case OMPD_flush:
2373   case OMPD_depobj:
2374   case OMPD_scan:
2375   case OMPD_taskyield:
2376   case OMPD_barrier:
2377   case OMPD_taskwait:
2378   case OMPD_cancellation_point:
2379   case OMPD_cancel:
2380   case OMPD_target_enter_data:
2381   case OMPD_target_exit_data:
2382   case OMPD_target_update:
2383   case OMPD_interop:
2384     if ((StmtCtx & ParsedStmtContext::AllowStandaloneOpenMPDirectives) ==
2385         ParsedStmtContext()) {
2386       Diag(Tok, diag::err_omp_immediate_directive)
2387           << getOpenMPDirectiveName(DKind) << 0;
2388     }
2389     HasAssociatedStatement = false;
2390     // Fall through for further analysis.
2391     LLVM_FALLTHROUGH;
2392   case OMPD_parallel:
2393   case OMPD_simd:
2394   case OMPD_tile:
2395   case OMPD_for:
2396   case OMPD_for_simd:
2397   case OMPD_sections:
2398   case OMPD_single:
2399   case OMPD_section:
2400   case OMPD_master:
2401   case OMPD_critical:
2402   case OMPD_parallel_for:
2403   case OMPD_parallel_for_simd:
2404   case OMPD_parallel_sections:
2405   case OMPD_parallel_master:
2406   case OMPD_task:
2407   case OMPD_ordered:
2408   case OMPD_atomic:
2409   case OMPD_target:
2410   case OMPD_teams:
2411   case OMPD_taskgroup:
2412   case OMPD_target_data:
2413   case OMPD_target_parallel:
2414   case OMPD_target_parallel_for:
2415   case OMPD_taskloop:
2416   case OMPD_taskloop_simd:
2417   case OMPD_master_taskloop:
2418   case OMPD_master_taskloop_simd:
2419   case OMPD_parallel_master_taskloop:
2420   case OMPD_parallel_master_taskloop_simd:
2421   case OMPD_distribute:
2422   case OMPD_distribute_parallel_for:
2423   case OMPD_distribute_parallel_for_simd:
2424   case OMPD_distribute_simd:
2425   case OMPD_target_parallel_for_simd:
2426   case OMPD_target_simd:
2427   case OMPD_teams_distribute:
2428   case OMPD_teams_distribute_simd:
2429   case OMPD_teams_distribute_parallel_for_simd:
2430   case OMPD_teams_distribute_parallel_for:
2431   case OMPD_target_teams:
2432   case OMPD_target_teams_distribute:
2433   case OMPD_target_teams_distribute_parallel_for:
2434   case OMPD_target_teams_distribute_parallel_for_simd:
2435   case OMPD_target_teams_distribute_simd:
2436   case OMPD_dispatch:
2437   case OMPD_masked: {
2438     // Special processing for flush and depobj clauses.
2439     Token ImplicitTok;
2440     bool ImplicitClauseAllowed = false;
2441     if (DKind == OMPD_flush || DKind == OMPD_depobj) {
2442       ImplicitTok = Tok;
2443       ImplicitClauseAllowed = true;
2444     }
2445     ConsumeToken();
2446     // Parse directive name of the 'critical' directive if any.
2447     if (DKind == OMPD_critical) {
2448       BalancedDelimiterTracker T(*this, tok::l_paren,
2449                                  tok::annot_pragma_openmp_end);
2450       if (!T.consumeOpen()) {
2451         if (Tok.isAnyIdentifier()) {
2452           DirName =
2453               DeclarationNameInfo(Tok.getIdentifierInfo(), Tok.getLocation());
2454           ConsumeAnyToken();
2455         } else {
2456           Diag(Tok, diag::err_omp_expected_identifier_for_critical);
2457         }
2458         T.consumeClose();
2459       }
2460     } else if (DKind == OMPD_cancellation_point || DKind == OMPD_cancel) {
2461       CancelRegion = parseOpenMPDirectiveKind(*this);
2462       if (Tok.isNot(tok::annot_pragma_openmp_end))
2463         ConsumeToken();
2464     }
2465 
2466     if (isOpenMPLoopDirective(DKind))
2467       ScopeFlags |= Scope::OpenMPLoopDirectiveScope;
2468     if (isOpenMPSimdDirective(DKind))
2469       ScopeFlags |= Scope::OpenMPSimdDirectiveScope;
2470     ParseScope OMPDirectiveScope(this, ScopeFlags);
2471     Actions.StartOpenMPDSABlock(DKind, DirName, Actions.getCurScope(), Loc);
2472 
2473     while (Tok.isNot(tok::annot_pragma_openmp_end)) {
2474       bool HasImplicitClause = false;
2475       if (ImplicitClauseAllowed && Tok.is(tok::l_paren)) {
2476         HasImplicitClause = true;
2477         // Push copy of the current token back to stream to properly parse
2478         // pseudo-clause OMPFlushClause or OMPDepobjClause.
2479         PP.EnterToken(Tok, /*IsReinject*/ true);
2480         PP.EnterToken(ImplicitTok, /*IsReinject*/ true);
2481         ConsumeAnyToken();
2482       }
2483       OpenMPClauseKind CKind = Tok.isAnnotation()
2484                                    ? OMPC_unknown
2485                                    : getOpenMPClauseKind(PP.getSpelling(Tok));
2486       if (HasImplicitClause) {
2487         assert(CKind == OMPC_unknown && "Must be unknown implicit clause.");
2488         if (DKind == OMPD_flush) {
2489           CKind = OMPC_flush;
2490         } else {
2491           assert(DKind == OMPD_depobj &&
2492                  "Expected flush or depobj directives.");
2493           CKind = OMPC_depobj;
2494         }
2495       }
2496       // No more implicit clauses allowed.
2497       ImplicitClauseAllowed = false;
2498       Actions.StartOpenMPClause(CKind);
2499       HasImplicitClause = false;
2500       OMPClause *Clause = ParseOpenMPClause(
2501           DKind, CKind, !FirstClauses[unsigned(CKind)].getInt());
2502       FirstClauses[unsigned(CKind)].setInt(true);
2503       if (Clause) {
2504         FirstClauses[unsigned(CKind)].setPointer(Clause);
2505         Clauses.push_back(Clause);
2506       }
2507 
2508       // Skip ',' if any.
2509       if (Tok.is(tok::comma))
2510         ConsumeToken();
2511       Actions.EndOpenMPClause();
2512     }
2513     // End location of the directive.
2514     EndLoc = Tok.getLocation();
2515     // Consume final annot_pragma_openmp_end.
2516     ConsumeAnnotationToken();
2517 
2518     // OpenMP [2.13.8, ordered Construct, Syntax]
2519     // If the depend clause is specified, the ordered construct is a stand-alone
2520     // directive.
2521     if (DKind == OMPD_ordered && FirstClauses[unsigned(OMPC_depend)].getInt()) {
2522       if ((StmtCtx & ParsedStmtContext::AllowStandaloneOpenMPDirectives) ==
2523           ParsedStmtContext()) {
2524         Diag(Loc, diag::err_omp_immediate_directive)
2525             << getOpenMPDirectiveName(DKind) << 1
2526             << getOpenMPClauseName(OMPC_depend);
2527       }
2528       HasAssociatedStatement = false;
2529     }
2530 
2531     if (DKind == OMPD_tile && !FirstClauses[unsigned(OMPC_sizes)].getInt()) {
2532       Diag(Loc, diag::err_omp_required_clause)
2533           << getOpenMPDirectiveName(OMPD_tile) << "sizes";
2534     }
2535 
2536     StmtResult AssociatedStmt;
2537     if (HasAssociatedStatement) {
2538       // The body is a block scope like in Lambdas and Blocks.
2539       Actions.ActOnOpenMPRegionStart(DKind, getCurScope());
2540       // FIXME: We create a bogus CompoundStmt scope to hold the contents of
2541       // the captured region. Code elsewhere assumes that any FunctionScopeInfo
2542       // should have at least one compound statement scope within it.
2543       ParsingOpenMPDirectiveRAII NormalScope(*this, /*Value=*/false);
2544       {
2545         Sema::CompoundScopeRAII Scope(Actions);
2546         AssociatedStmt = ParseStatement();
2547 
2548         if (AssociatedStmt.isUsable() && isOpenMPLoopDirective(DKind) &&
2549             getLangOpts().OpenMPIRBuilder)
2550           AssociatedStmt =
2551               Actions.ActOnOpenMPCanonicalLoop(AssociatedStmt.get());
2552       }
2553       AssociatedStmt = Actions.ActOnOpenMPRegionEnd(AssociatedStmt, Clauses);
2554     } else if (DKind == OMPD_target_update || DKind == OMPD_target_enter_data ||
2555                DKind == OMPD_target_exit_data) {
2556       Actions.ActOnOpenMPRegionStart(DKind, getCurScope());
2557       AssociatedStmt = (Sema::CompoundScopeRAII(Actions),
2558                         Actions.ActOnCompoundStmt(Loc, Loc, llvm::None,
2559                                                   /*isStmtExpr=*/false));
2560       AssociatedStmt = Actions.ActOnOpenMPRegionEnd(AssociatedStmt, Clauses);
2561     }
2562     Directive = Actions.ActOnOpenMPExecutableDirective(
2563         DKind, DirName, CancelRegion, Clauses, AssociatedStmt.get(), Loc,
2564         EndLoc);
2565 
2566     // Exit scope.
2567     Actions.EndOpenMPDSABlock(Directive.get());
2568     OMPDirectiveScope.Exit();
2569     break;
2570   }
2571   case OMPD_declare_simd:
2572   case OMPD_declare_target:
2573   case OMPD_end_declare_target:
2574   case OMPD_requires:
2575   case OMPD_begin_declare_variant:
2576   case OMPD_end_declare_variant:
2577   case OMPD_declare_variant:
2578     Diag(Tok, diag::err_omp_unexpected_directive)
2579         << 1 << getOpenMPDirectiveName(DKind);
2580     SkipUntil(tok::annot_pragma_openmp_end);
2581     break;
2582   case OMPD_unknown:
2583   default:
2584     Diag(Tok, diag::err_omp_unknown_directive);
2585     SkipUntil(tok::annot_pragma_openmp_end);
2586     break;
2587   }
2588   return Directive;
2589 }
2590 
2591 // Parses simple list:
2592 //   simple-variable-list:
2593 //         '(' id-expression {, id-expression} ')'
2594 //
2595 bool Parser::ParseOpenMPSimpleVarList(
2596     OpenMPDirectiveKind Kind,
2597     const llvm::function_ref<void(CXXScopeSpec &, DeclarationNameInfo)>
2598         &Callback,
2599     bool AllowScopeSpecifier) {
2600   // Parse '('.
2601   BalancedDelimiterTracker T(*this, tok::l_paren, tok::annot_pragma_openmp_end);
2602   if (T.expectAndConsume(diag::err_expected_lparen_after,
2603                          getOpenMPDirectiveName(Kind).data()))
2604     return true;
2605   bool IsCorrect = true;
2606   bool NoIdentIsFound = true;
2607 
2608   // Read tokens while ')' or annot_pragma_openmp_end is not found.
2609   while (Tok.isNot(tok::r_paren) && Tok.isNot(tok::annot_pragma_openmp_end)) {
2610     CXXScopeSpec SS;
2611     UnqualifiedId Name;
2612     // Read var name.
2613     Token PrevTok = Tok;
2614     NoIdentIsFound = false;
2615 
2616     if (AllowScopeSpecifier && getLangOpts().CPlusPlus &&
2617         ParseOptionalCXXScopeSpecifier(SS, /*ObjectType=*/nullptr,
2618                                        /*ObjectHadErrors=*/false, false)) {
2619       IsCorrect = false;
2620       SkipUntil(tok::comma, tok::r_paren, tok::annot_pragma_openmp_end,
2621                 StopBeforeMatch);
2622     } else if (ParseUnqualifiedId(SS, /*ObjectType=*/nullptr,
2623                                   /*ObjectHadErrors=*/false, false, false,
2624                                   false, false, nullptr, Name)) {
2625       IsCorrect = false;
2626       SkipUntil(tok::comma, tok::r_paren, tok::annot_pragma_openmp_end,
2627                 StopBeforeMatch);
2628     } else if (Tok.isNot(tok::comma) && Tok.isNot(tok::r_paren) &&
2629                Tok.isNot(tok::annot_pragma_openmp_end)) {
2630       IsCorrect = false;
2631       SkipUntil(tok::comma, tok::r_paren, tok::annot_pragma_openmp_end,
2632                 StopBeforeMatch);
2633       Diag(PrevTok.getLocation(), diag::err_expected)
2634           << tok::identifier
2635           << SourceRange(PrevTok.getLocation(), PrevTokLocation);
2636     } else {
2637       Callback(SS, Actions.GetNameFromUnqualifiedId(Name));
2638     }
2639     // Consume ','.
2640     if (Tok.is(tok::comma)) {
2641       ConsumeToken();
2642     }
2643   }
2644 
2645   if (NoIdentIsFound) {
2646     Diag(Tok, diag::err_expected) << tok::identifier;
2647     IsCorrect = false;
2648   }
2649 
2650   // Parse ')'.
2651   IsCorrect = !T.consumeClose() && IsCorrect;
2652 
2653   return !IsCorrect;
2654 }
2655 
2656 OMPClause *Parser::ParseOpenMPSizesClause() {
2657   SourceLocation ClauseNameLoc = ConsumeToken();
2658   SmallVector<Expr *, 4> ValExprs;
2659 
2660   BalancedDelimiterTracker T(*this, tok::l_paren, tok::annot_pragma_openmp_end);
2661   if (T.consumeOpen()) {
2662     Diag(Tok, diag::err_expected) << tok::l_paren;
2663     return nullptr;
2664   }
2665 
2666   while (true) {
2667     ExprResult Val = ParseConstantExpression();
2668     if (!Val.isUsable()) {
2669       T.skipToEnd();
2670       return nullptr;
2671     }
2672 
2673     ValExprs.push_back(Val.get());
2674 
2675     if (Tok.is(tok::r_paren) || Tok.is(tok::annot_pragma_openmp_end))
2676       break;
2677 
2678     ExpectAndConsume(tok::comma);
2679   }
2680 
2681   T.consumeClose();
2682 
2683   return Actions.ActOnOpenMPSizesClause(
2684       ValExprs, ClauseNameLoc, T.getOpenLocation(), T.getCloseLocation());
2685 }
2686 
2687 OMPClause *Parser::ParseOpenMPUsesAllocatorClause(OpenMPDirectiveKind DKind) {
2688   SourceLocation Loc = Tok.getLocation();
2689   ConsumeAnyToken();
2690 
2691   // Parse '('.
2692   BalancedDelimiterTracker T(*this, tok::l_paren, tok::annot_pragma_openmp_end);
2693   if (T.expectAndConsume(diag::err_expected_lparen_after, "uses_allocator"))
2694     return nullptr;
2695   SmallVector<Sema::UsesAllocatorsData, 4> Data;
2696   do {
2697     ExprResult Allocator = ParseCXXIdExpression();
2698     if (Allocator.isInvalid()) {
2699       SkipUntil(tok::comma, tok::r_paren, tok::annot_pragma_openmp_end,
2700                 StopBeforeMatch);
2701       break;
2702     }
2703     Sema::UsesAllocatorsData &D = Data.emplace_back();
2704     D.Allocator = Allocator.get();
2705     if (Tok.is(tok::l_paren)) {
2706       BalancedDelimiterTracker T(*this, tok::l_paren,
2707                                  tok::annot_pragma_openmp_end);
2708       T.consumeOpen();
2709       ExprResult AllocatorTraits = ParseCXXIdExpression();
2710       T.consumeClose();
2711       if (AllocatorTraits.isInvalid()) {
2712         SkipUntil(tok::comma, tok::r_paren, tok::annot_pragma_openmp_end,
2713                   StopBeforeMatch);
2714         break;
2715       }
2716       D.AllocatorTraits = AllocatorTraits.get();
2717       D.LParenLoc = T.getOpenLocation();
2718       D.RParenLoc = T.getCloseLocation();
2719     }
2720     if (Tok.isNot(tok::comma) && Tok.isNot(tok::r_paren))
2721       Diag(Tok, diag::err_omp_expected_punc) << "uses_allocators" << 0;
2722     // Parse ','
2723     if (Tok.is(tok::comma))
2724       ConsumeAnyToken();
2725   } while (Tok.isNot(tok::r_paren) && Tok.isNot(tok::annot_pragma_openmp_end));
2726   T.consumeClose();
2727   return Actions.ActOnOpenMPUsesAllocatorClause(Loc, T.getOpenLocation(),
2728                                                 T.getCloseLocation(), Data);
2729 }
2730 
2731 /// Parsing of OpenMP clauses.
2732 ///
2733 ///    clause:
2734 ///       if-clause | final-clause | num_threads-clause | safelen-clause |
2735 ///       default-clause | private-clause | firstprivate-clause | shared-clause
2736 ///       | linear-clause | aligned-clause | collapse-clause |
2737 ///       lastprivate-clause | reduction-clause | proc_bind-clause |
2738 ///       schedule-clause | copyin-clause | copyprivate-clause | untied-clause |
2739 ///       mergeable-clause | flush-clause | read-clause | write-clause |
2740 ///       update-clause | capture-clause | seq_cst-clause | device-clause |
2741 ///       simdlen-clause | threads-clause | simd-clause | num_teams-clause |
2742 ///       thread_limit-clause | priority-clause | grainsize-clause |
2743 ///       nogroup-clause | num_tasks-clause | hint-clause | to-clause |
2744 ///       from-clause | is_device_ptr-clause | task_reduction-clause |
2745 ///       in_reduction-clause | allocator-clause | allocate-clause |
2746 ///       acq_rel-clause | acquire-clause | release-clause | relaxed-clause |
2747 ///       depobj-clause | destroy-clause | detach-clause | inclusive-clause |
2748 ///       exclusive-clause | uses_allocators-clause | use_device_addr-clause
2749 ///
2750 OMPClause *Parser::ParseOpenMPClause(OpenMPDirectiveKind DKind,
2751                                      OpenMPClauseKind CKind, bool FirstClause) {
2752   OMPClauseKind = CKind;
2753   OMPClause *Clause = nullptr;
2754   bool ErrorFound = false;
2755   bool WrongDirective = false;
2756   // Check if clause is allowed for the given directive.
2757   if (CKind != OMPC_unknown &&
2758       !isAllowedClauseForDirective(DKind, CKind, getLangOpts().OpenMP)) {
2759     Diag(Tok, diag::err_omp_unexpected_clause)
2760         << getOpenMPClauseName(CKind) << getOpenMPDirectiveName(DKind);
2761     ErrorFound = true;
2762     WrongDirective = true;
2763   }
2764 
2765   switch (CKind) {
2766   case OMPC_final:
2767   case OMPC_num_threads:
2768   case OMPC_safelen:
2769   case OMPC_simdlen:
2770   case OMPC_collapse:
2771   case OMPC_ordered:
2772   case OMPC_num_teams:
2773   case OMPC_thread_limit:
2774   case OMPC_priority:
2775   case OMPC_grainsize:
2776   case OMPC_num_tasks:
2777   case OMPC_hint:
2778   case OMPC_allocator:
2779   case OMPC_depobj:
2780   case OMPC_detach:
2781   case OMPC_novariants:
2782   case OMPC_nocontext:
2783   case OMPC_filter:
2784     // OpenMP [2.5, Restrictions]
2785     //  At most one num_threads clause can appear on the directive.
2786     // OpenMP [2.8.1, simd construct, Restrictions]
2787     //  Only one safelen  clause can appear on a simd directive.
2788     //  Only one simdlen  clause can appear on a simd directive.
2789     //  Only one collapse clause can appear on a simd directive.
2790     // OpenMP [2.11.1, task Construct, Restrictions]
2791     //  At most one if clause can appear on the directive.
2792     //  At most one final clause can appear on the directive.
2793     // OpenMP [teams Construct, Restrictions]
2794     //  At most one num_teams clause can appear on the directive.
2795     //  At most one thread_limit clause can appear on the directive.
2796     // OpenMP [2.9.1, task Construct, Restrictions]
2797     // At most one priority clause can appear on the directive.
2798     // OpenMP [2.9.2, taskloop Construct, Restrictions]
2799     // At most one grainsize clause can appear on the directive.
2800     // OpenMP [2.9.2, taskloop Construct, Restrictions]
2801     // At most one num_tasks clause can appear on the directive.
2802     // OpenMP [2.11.3, allocate Directive, Restrictions]
2803     // At most one allocator clause can appear on the directive.
2804     // OpenMP 5.0, 2.10.1 task Construct, Restrictions.
2805     // At most one detach clause can appear on the directive.
2806     // OpenMP 5.1, 2.3.6 dispatch Construct, Restrictions.
2807     // At most one novariants clause can appear on a dispatch directive.
2808     // At most one nocontext clause can appear on a dispatch directive.
2809     if (!FirstClause) {
2810       Diag(Tok, diag::err_omp_more_one_clause)
2811           << getOpenMPDirectiveName(DKind) << getOpenMPClauseName(CKind) << 0;
2812       ErrorFound = true;
2813     }
2814 
2815     if (CKind == OMPC_ordered && PP.LookAhead(/*N=*/0).isNot(tok::l_paren))
2816       Clause = ParseOpenMPClause(CKind, WrongDirective);
2817     else
2818       Clause = ParseOpenMPSingleExprClause(CKind, WrongDirective);
2819     break;
2820   case OMPC_default:
2821   case OMPC_proc_bind:
2822   case OMPC_atomic_default_mem_order:
2823   case OMPC_order:
2824     // OpenMP [2.14.3.1, Restrictions]
2825     //  Only a single default clause may be specified on a parallel, task or
2826     //  teams directive.
2827     // OpenMP [2.5, parallel Construct, Restrictions]
2828     //  At most one proc_bind clause can appear on the directive.
2829     // OpenMP [5.0, Requires directive, Restrictions]
2830     //  At most one atomic_default_mem_order clause can appear
2831     //  on the directive
2832     if (!FirstClause && CKind != OMPC_order) {
2833       Diag(Tok, diag::err_omp_more_one_clause)
2834           << getOpenMPDirectiveName(DKind) << getOpenMPClauseName(CKind) << 0;
2835       ErrorFound = true;
2836     }
2837 
2838     Clause = ParseOpenMPSimpleClause(CKind, WrongDirective);
2839     break;
2840   case OMPC_device:
2841   case OMPC_schedule:
2842   case OMPC_dist_schedule:
2843   case OMPC_defaultmap:
2844     // OpenMP [2.7.1, Restrictions, p. 3]
2845     //  Only one schedule clause can appear on a loop directive.
2846     // OpenMP 4.5 [2.10.4, Restrictions, p. 106]
2847     //  At most one defaultmap clause can appear on the directive.
2848     // OpenMP 5.0 [2.12.5, target construct, Restrictions]
2849     //  At most one device clause can appear on the directive.
2850     if ((getLangOpts().OpenMP < 50 || CKind != OMPC_defaultmap) &&
2851         !FirstClause) {
2852       Diag(Tok, diag::err_omp_more_one_clause)
2853           << getOpenMPDirectiveName(DKind) << getOpenMPClauseName(CKind) << 0;
2854       ErrorFound = true;
2855     }
2856     LLVM_FALLTHROUGH;
2857   case OMPC_if:
2858     Clause = ParseOpenMPSingleExprWithArgClause(DKind, CKind, WrongDirective);
2859     break;
2860   case OMPC_nowait:
2861   case OMPC_untied:
2862   case OMPC_mergeable:
2863   case OMPC_read:
2864   case OMPC_write:
2865   case OMPC_capture:
2866   case OMPC_seq_cst:
2867   case OMPC_acq_rel:
2868   case OMPC_acquire:
2869   case OMPC_release:
2870   case OMPC_relaxed:
2871   case OMPC_threads:
2872   case OMPC_simd:
2873   case OMPC_nogroup:
2874   case OMPC_unified_address:
2875   case OMPC_unified_shared_memory:
2876   case OMPC_reverse_offload:
2877   case OMPC_dynamic_allocators:
2878     // OpenMP [2.7.1, Restrictions, p. 9]
2879     //  Only one ordered clause can appear on a loop directive.
2880     // OpenMP [2.7.1, Restrictions, C/C++, p. 4]
2881     //  Only one nowait clause can appear on a for directive.
2882     // OpenMP [5.0, Requires directive, Restrictions]
2883     //   Each of the requires clauses can appear at most once on the directive.
2884     if (!FirstClause) {
2885       Diag(Tok, diag::err_omp_more_one_clause)
2886           << getOpenMPDirectiveName(DKind) << getOpenMPClauseName(CKind) << 0;
2887       ErrorFound = true;
2888     }
2889 
2890     Clause = ParseOpenMPClause(CKind, WrongDirective);
2891     break;
2892   case OMPC_update:
2893     if (!FirstClause) {
2894       Diag(Tok, diag::err_omp_more_one_clause)
2895           << getOpenMPDirectiveName(DKind) << getOpenMPClauseName(CKind) << 0;
2896       ErrorFound = true;
2897     }
2898 
2899     Clause = (DKind == OMPD_depobj)
2900                  ? ParseOpenMPSimpleClause(CKind, WrongDirective)
2901                  : ParseOpenMPClause(CKind, WrongDirective);
2902     break;
2903   case OMPC_private:
2904   case OMPC_firstprivate:
2905   case OMPC_lastprivate:
2906   case OMPC_shared:
2907   case OMPC_reduction:
2908   case OMPC_task_reduction:
2909   case OMPC_in_reduction:
2910   case OMPC_linear:
2911   case OMPC_aligned:
2912   case OMPC_copyin:
2913   case OMPC_copyprivate:
2914   case OMPC_flush:
2915   case OMPC_depend:
2916   case OMPC_map:
2917   case OMPC_to:
2918   case OMPC_from:
2919   case OMPC_use_device_ptr:
2920   case OMPC_use_device_addr:
2921   case OMPC_is_device_ptr:
2922   case OMPC_allocate:
2923   case OMPC_nontemporal:
2924   case OMPC_inclusive:
2925   case OMPC_exclusive:
2926   case OMPC_affinity:
2927     Clause = ParseOpenMPVarListClause(DKind, CKind, WrongDirective);
2928     break;
2929   case OMPC_sizes:
2930     if (!FirstClause) {
2931       Diag(Tok, diag::err_omp_more_one_clause)
2932           << getOpenMPDirectiveName(DKind) << getOpenMPClauseName(CKind) << 0;
2933       ErrorFound = true;
2934     }
2935 
2936     Clause = ParseOpenMPSizesClause();
2937     break;
2938   case OMPC_uses_allocators:
2939     Clause = ParseOpenMPUsesAllocatorClause(DKind);
2940     break;
2941   case OMPC_destroy:
2942     if (DKind != OMPD_interop) {
2943       if (!FirstClause) {
2944         Diag(Tok, diag::err_omp_more_one_clause)
2945             << getOpenMPDirectiveName(DKind) << getOpenMPClauseName(CKind) << 0;
2946         ErrorFound = true;
2947       }
2948       Clause = ParseOpenMPClause(CKind, WrongDirective);
2949       break;
2950     }
2951     LLVM_FALLTHROUGH;
2952   case OMPC_init:
2953   case OMPC_use:
2954     Clause = ParseOpenMPInteropClause(CKind, WrongDirective);
2955     break;
2956   case OMPC_device_type:
2957   case OMPC_unknown:
2958     skipUntilPragmaOpenMPEnd(DKind);
2959     break;
2960   case OMPC_threadprivate:
2961   case OMPC_uniform:
2962   case OMPC_match:
2963     if (!WrongDirective)
2964       Diag(Tok, diag::err_omp_unexpected_clause)
2965           << getOpenMPClauseName(CKind) << getOpenMPDirectiveName(DKind);
2966     SkipUntil(tok::comma, tok::annot_pragma_openmp_end, StopBeforeMatch);
2967     break;
2968   default:
2969     break;
2970   }
2971   return ErrorFound ? nullptr : Clause;
2972 }
2973 
2974 /// Parses simple expression in parens for single-expression clauses of OpenMP
2975 /// constructs.
2976 /// \param RLoc Returned location of right paren.
2977 ExprResult Parser::ParseOpenMPParensExpr(StringRef ClauseName,
2978                                          SourceLocation &RLoc,
2979                                          bool IsAddressOfOperand) {
2980   BalancedDelimiterTracker T(*this, tok::l_paren, tok::annot_pragma_openmp_end);
2981   if (T.expectAndConsume(diag::err_expected_lparen_after, ClauseName.data()))
2982     return ExprError();
2983 
2984   SourceLocation ELoc = Tok.getLocation();
2985   ExprResult LHS(
2986       ParseCastExpression(AnyCastExpr, IsAddressOfOperand, NotTypeCast));
2987   ExprResult Val(ParseRHSOfBinaryExpression(LHS, prec::Conditional));
2988   Val = Actions.ActOnFinishFullExpr(Val.get(), ELoc, /*DiscardedValue*/ false);
2989 
2990   // Parse ')'.
2991   RLoc = Tok.getLocation();
2992   if (!T.consumeClose())
2993     RLoc = T.getCloseLocation();
2994 
2995   return Val;
2996 }
2997 
2998 /// Parsing of OpenMP clauses with single expressions like 'final',
2999 /// 'collapse', 'safelen', 'num_threads', 'simdlen', 'num_teams',
3000 /// 'thread_limit', 'simdlen', 'priority', 'grainsize', 'num_tasks', 'hint' or
3001 /// 'detach'.
3002 ///
3003 ///    final-clause:
3004 ///      'final' '(' expression ')'
3005 ///
3006 ///    num_threads-clause:
3007 ///      'num_threads' '(' expression ')'
3008 ///
3009 ///    safelen-clause:
3010 ///      'safelen' '(' expression ')'
3011 ///
3012 ///    simdlen-clause:
3013 ///      'simdlen' '(' expression ')'
3014 ///
3015 ///    collapse-clause:
3016 ///      'collapse' '(' expression ')'
3017 ///
3018 ///    priority-clause:
3019 ///      'priority' '(' expression ')'
3020 ///
3021 ///    grainsize-clause:
3022 ///      'grainsize' '(' expression ')'
3023 ///
3024 ///    num_tasks-clause:
3025 ///      'num_tasks' '(' expression ')'
3026 ///
3027 ///    hint-clause:
3028 ///      'hint' '(' expression ')'
3029 ///
3030 ///    allocator-clause:
3031 ///      'allocator' '(' expression ')'
3032 ///
3033 ///    detach-clause:
3034 ///      'detach' '(' event-handler-expression ')'
3035 ///
3036 OMPClause *Parser::ParseOpenMPSingleExprClause(OpenMPClauseKind Kind,
3037                                                bool ParseOnly) {
3038   SourceLocation Loc = ConsumeToken();
3039   SourceLocation LLoc = Tok.getLocation();
3040   SourceLocation RLoc;
3041 
3042   ExprResult Val = ParseOpenMPParensExpr(getOpenMPClauseName(Kind), RLoc);
3043 
3044   if (Val.isInvalid())
3045     return nullptr;
3046 
3047   if (ParseOnly)
3048     return nullptr;
3049   return Actions.ActOnOpenMPSingleExprClause(Kind, Val.get(), Loc, LLoc, RLoc);
3050 }
3051 
3052 /// Parsing of OpenMP clauses that use an interop-var.
3053 ///
3054 /// init-clause:
3055 ///   init([interop-modifier, ]interop-type[[, interop-type] ... ]:interop-var)
3056 ///
3057 /// destroy-clause:
3058 ///   destroy(interop-var)
3059 ///
3060 /// use-clause:
3061 ///   use(interop-var)
3062 ///
3063 /// interop-modifier:
3064 ///   prefer_type(preference-list)
3065 ///
3066 /// preference-list:
3067 ///   foreign-runtime-id [, foreign-runtime-id]...
3068 ///
3069 /// foreign-runtime-id:
3070 ///   <string-literal> | <constant-integral-expression>
3071 ///
3072 /// interop-type:
3073 ///   target | targetsync
3074 ///
3075 OMPClause *Parser::ParseOpenMPInteropClause(OpenMPClauseKind Kind,
3076                                             bool ParseOnly) {
3077   SourceLocation Loc = ConsumeToken();
3078   // Parse '('.
3079   BalancedDelimiterTracker T(*this, tok::l_paren, tok::annot_pragma_openmp_end);
3080   if (T.expectAndConsume(diag::err_expected_lparen_after,
3081                          getOpenMPClauseName(Kind).data()))
3082     return nullptr;
3083 
3084   bool IsTarget = false;
3085   bool IsTargetSync = false;
3086   SmallVector<Expr *, 4> Prefs;
3087 
3088   if (Kind == OMPC_init) {
3089 
3090     // Parse optional interop-modifier.
3091     if (Tok.is(tok::identifier) && PP.getSpelling(Tok) == "prefer_type") {
3092       ConsumeToken();
3093       BalancedDelimiterTracker PT(*this, tok::l_paren,
3094                                   tok::annot_pragma_openmp_end);
3095       if (PT.expectAndConsume(diag::err_expected_lparen_after, "prefer_type"))
3096         return nullptr;
3097 
3098       while (Tok.isNot(tok::r_paren)) {
3099         SourceLocation Loc = Tok.getLocation();
3100         ExprResult LHS = ParseCastExpression(AnyCastExpr);
3101         ExprResult PTExpr = Actions.CorrectDelayedTyposInExpr(
3102             ParseRHSOfBinaryExpression(LHS, prec::Conditional));
3103         PTExpr = Actions.ActOnFinishFullExpr(PTExpr.get(), Loc,
3104                                              /*DiscardedValue=*/false);
3105         if (PTExpr.isUsable())
3106           Prefs.push_back(PTExpr.get());
3107         else
3108           SkipUntil(tok::comma, tok::r_paren, tok::annot_pragma_openmp_end,
3109                     StopBeforeMatch);
3110 
3111         if (Tok.is(tok::comma))
3112           ConsumeToken();
3113       }
3114       PT.consumeClose();
3115     }
3116 
3117     if (!Prefs.empty()) {
3118       if (Tok.is(tok::comma))
3119         ConsumeToken();
3120       else
3121         Diag(Tok, diag::err_omp_expected_punc_after_interop_mod);
3122     }
3123 
3124     // Parse the interop-types.
3125     bool HasError = false;
3126     while (Tok.is(tok::identifier)) {
3127       if (PP.getSpelling(Tok) == "target") {
3128         // OpenMP 5.1 [2.15.1, interop Construct, Restrictions]
3129         // Each interop-type may be specified on an action-clause at most
3130         // once.
3131         if (IsTarget)
3132           Diag(Tok, diag::warn_omp_more_one_interop_type) << "target";
3133         IsTarget = true;
3134       } else if (PP.getSpelling(Tok) == "targetsync") {
3135         if (IsTargetSync)
3136           Diag(Tok, diag::warn_omp_more_one_interop_type) << "targetsync";
3137         IsTargetSync = true;
3138       } else {
3139         HasError = true;
3140         Diag(Tok, diag::err_omp_expected_interop_type);
3141       }
3142       ConsumeToken();
3143 
3144       if (!Tok.is(tok::comma))
3145         break;
3146       ConsumeToken();
3147     }
3148     if (!HasError && !IsTarget && !IsTargetSync)
3149       Diag(Tok, diag::err_omp_expected_interop_type);
3150 
3151     if (Tok.is(tok::colon))
3152       ConsumeToken();
3153     else if (IsTarget || IsTargetSync)
3154       Diag(Tok, diag::warn_pragma_expected_colon) << "interop types";
3155   }
3156 
3157   // Parse the variable.
3158   SourceLocation VarLoc = Tok.getLocation();
3159   ExprResult InteropVarExpr =
3160       Actions.CorrectDelayedTyposInExpr(ParseAssignmentExpression());
3161   if (!InteropVarExpr.isUsable()) {
3162     SkipUntil(tok::comma, tok::r_paren, tok::annot_pragma_openmp_end,
3163               StopBeforeMatch);
3164   }
3165 
3166   // Parse ')'.
3167   SourceLocation RLoc = Tok.getLocation();
3168   if (!T.consumeClose())
3169     RLoc = T.getCloseLocation();
3170 
3171   if (ParseOnly || !InteropVarExpr.isUsable() ||
3172       (Kind == OMPC_init && !IsTarget && !IsTargetSync))
3173     return nullptr;
3174 
3175   if (Kind == OMPC_init)
3176     return Actions.ActOnOpenMPInitClause(InteropVarExpr.get(), Prefs, IsTarget,
3177                                          IsTargetSync, Loc, T.getOpenLocation(),
3178                                          VarLoc, RLoc);
3179   if (Kind == OMPC_use)
3180     return Actions.ActOnOpenMPUseClause(InteropVarExpr.get(), Loc,
3181                                         T.getOpenLocation(), VarLoc, RLoc);
3182 
3183   if (Kind == OMPC_destroy)
3184     return Actions.ActOnOpenMPDestroyClause(InteropVarExpr.get(), Loc,
3185                                             T.getOpenLocation(), VarLoc, RLoc);
3186 
3187   llvm_unreachable("Unexpected interop variable clause.");
3188 }
3189 
3190 /// Parsing of simple OpenMP clauses like 'default' or 'proc_bind'.
3191 ///
3192 ///    default-clause:
3193 ///         'default' '(' 'none' | 'shared' | 'firstprivate' ')'
3194 ///
3195 ///    proc_bind-clause:
3196 ///         'proc_bind' '(' 'master' | 'close' | 'spread' ')'
3197 ///
3198 ///    update-clause:
3199 ///         'update' '(' 'in' | 'out' | 'inout' | 'mutexinoutset' ')'
3200 ///
3201 OMPClause *Parser::ParseOpenMPSimpleClause(OpenMPClauseKind Kind,
3202                                            bool ParseOnly) {
3203   llvm::Optional<SimpleClauseData> Val = parseOpenMPSimpleClause(*this, Kind);
3204   if (!Val || ParseOnly)
3205     return nullptr;
3206   if (getLangOpts().OpenMP < 51 && Kind == OMPC_default &&
3207       static_cast<DefaultKind>(Val.getValue().Type) ==
3208           OMP_DEFAULT_firstprivate) {
3209     Diag(Val.getValue().LOpen, diag::err_omp_invalid_dsa)
3210         << getOpenMPClauseName(OMPC_firstprivate)
3211         << getOpenMPClauseName(OMPC_default) << "5.1";
3212     return nullptr;
3213   }
3214   return Actions.ActOnOpenMPSimpleClause(
3215       Kind, Val.getValue().Type, Val.getValue().TypeLoc, Val.getValue().LOpen,
3216       Val.getValue().Loc, Val.getValue().RLoc);
3217 }
3218 
3219 /// Parsing of OpenMP clauses like 'ordered'.
3220 ///
3221 ///    ordered-clause:
3222 ///         'ordered'
3223 ///
3224 ///    nowait-clause:
3225 ///         'nowait'
3226 ///
3227 ///    untied-clause:
3228 ///         'untied'
3229 ///
3230 ///    mergeable-clause:
3231 ///         'mergeable'
3232 ///
3233 ///    read-clause:
3234 ///         'read'
3235 ///
3236 ///    threads-clause:
3237 ///         'threads'
3238 ///
3239 ///    simd-clause:
3240 ///         'simd'
3241 ///
3242 ///    nogroup-clause:
3243 ///         'nogroup'
3244 ///
3245 OMPClause *Parser::ParseOpenMPClause(OpenMPClauseKind Kind, bool ParseOnly) {
3246   SourceLocation Loc = Tok.getLocation();
3247   ConsumeAnyToken();
3248 
3249   if (ParseOnly)
3250     return nullptr;
3251   return Actions.ActOnOpenMPClause(Kind, Loc, Tok.getLocation());
3252 }
3253 
3254 /// Parsing of OpenMP clauses with single expressions and some additional
3255 /// argument like 'schedule' or 'dist_schedule'.
3256 ///
3257 ///    schedule-clause:
3258 ///      'schedule' '(' [ modifier [ ',' modifier ] ':' ] kind [',' expression ]
3259 ///      ')'
3260 ///
3261 ///    if-clause:
3262 ///      'if' '(' [ directive-name-modifier ':' ] expression ')'
3263 ///
3264 ///    defaultmap:
3265 ///      'defaultmap' '(' modifier [ ':' kind ] ')'
3266 ///
3267 ///    device-clause:
3268 ///      'device' '(' [ device-modifier ':' ] expression ')'
3269 ///
3270 OMPClause *Parser::ParseOpenMPSingleExprWithArgClause(OpenMPDirectiveKind DKind,
3271                                                       OpenMPClauseKind Kind,
3272                                                       bool ParseOnly) {
3273   SourceLocation Loc = ConsumeToken();
3274   SourceLocation DelimLoc;
3275   // Parse '('.
3276   BalancedDelimiterTracker T(*this, tok::l_paren, tok::annot_pragma_openmp_end);
3277   if (T.expectAndConsume(diag::err_expected_lparen_after,
3278                          getOpenMPClauseName(Kind).data()))
3279     return nullptr;
3280 
3281   ExprResult Val;
3282   SmallVector<unsigned, 4> Arg;
3283   SmallVector<SourceLocation, 4> KLoc;
3284   if (Kind == OMPC_schedule) {
3285     enum { Modifier1, Modifier2, ScheduleKind, NumberOfElements };
3286     Arg.resize(NumberOfElements);
3287     KLoc.resize(NumberOfElements);
3288     Arg[Modifier1] = OMPC_SCHEDULE_MODIFIER_unknown;
3289     Arg[Modifier2] = OMPC_SCHEDULE_MODIFIER_unknown;
3290     Arg[ScheduleKind] = OMPC_SCHEDULE_unknown;
3291     unsigned KindModifier = getOpenMPSimpleClauseType(
3292         Kind, Tok.isAnnotation() ? "" : PP.getSpelling(Tok),
3293         getLangOpts().OpenMP);
3294     if (KindModifier > OMPC_SCHEDULE_unknown) {
3295       // Parse 'modifier'
3296       Arg[Modifier1] = KindModifier;
3297       KLoc[Modifier1] = Tok.getLocation();
3298       if (Tok.isNot(tok::r_paren) && Tok.isNot(tok::comma) &&
3299           Tok.isNot(tok::annot_pragma_openmp_end))
3300         ConsumeAnyToken();
3301       if (Tok.is(tok::comma)) {
3302         // Parse ',' 'modifier'
3303         ConsumeAnyToken();
3304         KindModifier = getOpenMPSimpleClauseType(
3305             Kind, Tok.isAnnotation() ? "" : PP.getSpelling(Tok),
3306             getLangOpts().OpenMP);
3307         Arg[Modifier2] = KindModifier > OMPC_SCHEDULE_unknown
3308                              ? KindModifier
3309                              : (unsigned)OMPC_SCHEDULE_unknown;
3310         KLoc[Modifier2] = Tok.getLocation();
3311         if (Tok.isNot(tok::r_paren) && Tok.isNot(tok::comma) &&
3312             Tok.isNot(tok::annot_pragma_openmp_end))
3313           ConsumeAnyToken();
3314       }
3315       // Parse ':'
3316       if (Tok.is(tok::colon))
3317         ConsumeAnyToken();
3318       else
3319         Diag(Tok, diag::warn_pragma_expected_colon) << "schedule modifier";
3320       KindModifier = getOpenMPSimpleClauseType(
3321           Kind, Tok.isAnnotation() ? "" : PP.getSpelling(Tok),
3322           getLangOpts().OpenMP);
3323     }
3324     Arg[ScheduleKind] = KindModifier;
3325     KLoc[ScheduleKind] = Tok.getLocation();
3326     if (Tok.isNot(tok::r_paren) && Tok.isNot(tok::comma) &&
3327         Tok.isNot(tok::annot_pragma_openmp_end))
3328       ConsumeAnyToken();
3329     if ((Arg[ScheduleKind] == OMPC_SCHEDULE_static ||
3330          Arg[ScheduleKind] == OMPC_SCHEDULE_dynamic ||
3331          Arg[ScheduleKind] == OMPC_SCHEDULE_guided) &&
3332         Tok.is(tok::comma))
3333       DelimLoc = ConsumeAnyToken();
3334   } else if (Kind == OMPC_dist_schedule) {
3335     Arg.push_back(getOpenMPSimpleClauseType(
3336         Kind, Tok.isAnnotation() ? "" : PP.getSpelling(Tok),
3337         getLangOpts().OpenMP));
3338     KLoc.push_back(Tok.getLocation());
3339     if (Tok.isNot(tok::r_paren) && Tok.isNot(tok::comma) &&
3340         Tok.isNot(tok::annot_pragma_openmp_end))
3341       ConsumeAnyToken();
3342     if (Arg.back() == OMPC_DIST_SCHEDULE_static && Tok.is(tok::comma))
3343       DelimLoc = ConsumeAnyToken();
3344   } else if (Kind == OMPC_defaultmap) {
3345     // Get a defaultmap modifier
3346     unsigned Modifier = getOpenMPSimpleClauseType(
3347         Kind, Tok.isAnnotation() ? "" : PP.getSpelling(Tok),
3348         getLangOpts().OpenMP);
3349     // Set defaultmap modifier to unknown if it is either scalar, aggregate, or
3350     // pointer
3351     if (Modifier < OMPC_DEFAULTMAP_MODIFIER_unknown)
3352       Modifier = OMPC_DEFAULTMAP_MODIFIER_unknown;
3353     Arg.push_back(Modifier);
3354     KLoc.push_back(Tok.getLocation());
3355     if (Tok.isNot(tok::r_paren) && Tok.isNot(tok::comma) &&
3356         Tok.isNot(tok::annot_pragma_openmp_end))
3357       ConsumeAnyToken();
3358     // Parse ':'
3359     if (Tok.is(tok::colon) || getLangOpts().OpenMP < 50) {
3360       if (Tok.is(tok::colon))
3361         ConsumeAnyToken();
3362       else if (Arg.back() != OMPC_DEFAULTMAP_MODIFIER_unknown)
3363         Diag(Tok, diag::warn_pragma_expected_colon) << "defaultmap modifier";
3364       // Get a defaultmap kind
3365       Arg.push_back(getOpenMPSimpleClauseType(
3366           Kind, Tok.isAnnotation() ? "" : PP.getSpelling(Tok),
3367           getLangOpts().OpenMP));
3368       KLoc.push_back(Tok.getLocation());
3369       if (Tok.isNot(tok::r_paren) && Tok.isNot(tok::comma) &&
3370           Tok.isNot(tok::annot_pragma_openmp_end))
3371         ConsumeAnyToken();
3372     } else {
3373       Arg.push_back(OMPC_DEFAULTMAP_unknown);
3374       KLoc.push_back(SourceLocation());
3375     }
3376   } else if (Kind == OMPC_device) {
3377     // Only target executable directives support extended device construct.
3378     if (isOpenMPTargetExecutionDirective(DKind) && getLangOpts().OpenMP >= 50 &&
3379         NextToken().is(tok::colon)) {
3380       // Parse optional <device modifier> ':'
3381       Arg.push_back(getOpenMPSimpleClauseType(
3382           Kind, Tok.isAnnotation() ? "" : PP.getSpelling(Tok),
3383           getLangOpts().OpenMP));
3384       KLoc.push_back(Tok.getLocation());
3385       ConsumeAnyToken();
3386       // Parse ':'
3387       ConsumeAnyToken();
3388     } else {
3389       Arg.push_back(OMPC_DEVICE_unknown);
3390       KLoc.emplace_back();
3391     }
3392   } else {
3393     assert(Kind == OMPC_if);
3394     KLoc.push_back(Tok.getLocation());
3395     TentativeParsingAction TPA(*this);
3396     auto DK = parseOpenMPDirectiveKind(*this);
3397     Arg.push_back(DK);
3398     if (DK != OMPD_unknown) {
3399       ConsumeToken();
3400       if (Tok.is(tok::colon) && getLangOpts().OpenMP > 40) {
3401         TPA.Commit();
3402         DelimLoc = ConsumeToken();
3403       } else {
3404         TPA.Revert();
3405         Arg.back() = unsigned(OMPD_unknown);
3406       }
3407     } else {
3408       TPA.Revert();
3409     }
3410   }
3411 
3412   bool NeedAnExpression = (Kind == OMPC_schedule && DelimLoc.isValid()) ||
3413                           (Kind == OMPC_dist_schedule && DelimLoc.isValid()) ||
3414                           Kind == OMPC_if || Kind == OMPC_device;
3415   if (NeedAnExpression) {
3416     SourceLocation ELoc = Tok.getLocation();
3417     ExprResult LHS(ParseCastExpression(AnyCastExpr, false, NotTypeCast));
3418     Val = ParseRHSOfBinaryExpression(LHS, prec::Conditional);
3419     Val =
3420         Actions.ActOnFinishFullExpr(Val.get(), ELoc, /*DiscardedValue*/ false);
3421   }
3422 
3423   // Parse ')'.
3424   SourceLocation RLoc = Tok.getLocation();
3425   if (!T.consumeClose())
3426     RLoc = T.getCloseLocation();
3427 
3428   if (NeedAnExpression && Val.isInvalid())
3429     return nullptr;
3430 
3431   if (ParseOnly)
3432     return nullptr;
3433   return Actions.ActOnOpenMPSingleExprWithArgClause(
3434       Kind, Arg, Val.get(), Loc, T.getOpenLocation(), KLoc, DelimLoc, RLoc);
3435 }
3436 
3437 static bool ParseReductionId(Parser &P, CXXScopeSpec &ReductionIdScopeSpec,
3438                              UnqualifiedId &ReductionId) {
3439   if (ReductionIdScopeSpec.isEmpty()) {
3440     auto OOK = OO_None;
3441     switch (P.getCurToken().getKind()) {
3442     case tok::plus:
3443       OOK = OO_Plus;
3444       break;
3445     case tok::minus:
3446       OOK = OO_Minus;
3447       break;
3448     case tok::star:
3449       OOK = OO_Star;
3450       break;
3451     case tok::amp:
3452       OOK = OO_Amp;
3453       break;
3454     case tok::pipe:
3455       OOK = OO_Pipe;
3456       break;
3457     case tok::caret:
3458       OOK = OO_Caret;
3459       break;
3460     case tok::ampamp:
3461       OOK = OO_AmpAmp;
3462       break;
3463     case tok::pipepipe:
3464       OOK = OO_PipePipe;
3465       break;
3466     default:
3467       break;
3468     }
3469     if (OOK != OO_None) {
3470       SourceLocation OpLoc = P.ConsumeToken();
3471       SourceLocation SymbolLocations[] = {OpLoc, OpLoc, SourceLocation()};
3472       ReductionId.setOperatorFunctionId(OpLoc, OOK, SymbolLocations);
3473       return false;
3474     }
3475   }
3476   return P.ParseUnqualifiedId(
3477       ReductionIdScopeSpec, /*ObjectType=*/nullptr,
3478       /*ObjectHadErrors=*/false, /*EnteringContext*/ false,
3479       /*AllowDestructorName*/ false,
3480       /*AllowConstructorName*/ false,
3481       /*AllowDeductionGuide*/ false, nullptr, ReductionId);
3482 }
3483 
3484 /// Checks if the token is a valid map-type-modifier.
3485 /// FIXME: It will return an OpenMPMapClauseKind if that's what it parses.
3486 static OpenMPMapModifierKind isMapModifier(Parser &P) {
3487   Token Tok = P.getCurToken();
3488   if (!Tok.is(tok::identifier))
3489     return OMPC_MAP_MODIFIER_unknown;
3490 
3491   Preprocessor &PP = P.getPreprocessor();
3492   OpenMPMapModifierKind TypeModifier =
3493       static_cast<OpenMPMapModifierKind>(getOpenMPSimpleClauseType(
3494           OMPC_map, PP.getSpelling(Tok), P.getLangOpts().OpenMP));
3495   return TypeModifier;
3496 }
3497 
3498 /// Parse the mapper modifier in map, to, and from clauses.
3499 bool Parser::parseMapperModifier(OpenMPVarListDataTy &Data) {
3500   // Parse '('.
3501   BalancedDelimiterTracker T(*this, tok::l_paren, tok::colon);
3502   if (T.expectAndConsume(diag::err_expected_lparen_after, "mapper")) {
3503     SkipUntil(tok::colon, tok::r_paren, tok::annot_pragma_openmp_end,
3504               StopBeforeMatch);
3505     return true;
3506   }
3507   // Parse mapper-identifier
3508   if (getLangOpts().CPlusPlus)
3509     ParseOptionalCXXScopeSpecifier(Data.ReductionOrMapperIdScopeSpec,
3510                                    /*ObjectType=*/nullptr,
3511                                    /*ObjectHadErrors=*/false,
3512                                    /*EnteringContext=*/false);
3513   if (Tok.isNot(tok::identifier) && Tok.isNot(tok::kw_default)) {
3514     Diag(Tok.getLocation(), diag::err_omp_mapper_illegal_identifier);
3515     SkipUntil(tok::colon, tok::r_paren, tok::annot_pragma_openmp_end,
3516               StopBeforeMatch);
3517     return true;
3518   }
3519   auto &DeclNames = Actions.getASTContext().DeclarationNames;
3520   Data.ReductionOrMapperId = DeclarationNameInfo(
3521       DeclNames.getIdentifier(Tok.getIdentifierInfo()), Tok.getLocation());
3522   ConsumeToken();
3523   // Parse ')'.
3524   return T.consumeClose();
3525 }
3526 
3527 /// Parse map-type-modifiers in map clause.
3528 /// map([ [map-type-modifier[,] [map-type-modifier[,] ...] map-type : ] list)
3529 /// where, map-type-modifier ::= always | close | mapper(mapper-identifier) |
3530 /// present
3531 bool Parser::parseMapTypeModifiers(OpenMPVarListDataTy &Data) {
3532   while (getCurToken().isNot(tok::colon)) {
3533     OpenMPMapModifierKind TypeModifier = isMapModifier(*this);
3534     if (TypeModifier == OMPC_MAP_MODIFIER_always ||
3535         TypeModifier == OMPC_MAP_MODIFIER_close ||
3536         TypeModifier == OMPC_MAP_MODIFIER_present) {
3537       Data.MapTypeModifiers.push_back(TypeModifier);
3538       Data.MapTypeModifiersLoc.push_back(Tok.getLocation());
3539       ConsumeToken();
3540     } else if (TypeModifier == OMPC_MAP_MODIFIER_mapper) {
3541       Data.MapTypeModifiers.push_back(TypeModifier);
3542       Data.MapTypeModifiersLoc.push_back(Tok.getLocation());
3543       ConsumeToken();
3544       if (parseMapperModifier(Data))
3545         return true;
3546     } else {
3547       // For the case of unknown map-type-modifier or a map-type.
3548       // Map-type is followed by a colon; the function returns when it
3549       // encounters a token followed by a colon.
3550       if (Tok.is(tok::comma)) {
3551         Diag(Tok, diag::err_omp_map_type_modifier_missing);
3552         ConsumeToken();
3553         continue;
3554       }
3555       // Potential map-type token as it is followed by a colon.
3556       if (PP.LookAhead(0).is(tok::colon))
3557         return false;
3558       Diag(Tok, diag::err_omp_unknown_map_type_modifier)
3559           << (getLangOpts().OpenMP >= 51 ? 1 : 0);
3560       ConsumeToken();
3561     }
3562     if (getCurToken().is(tok::comma))
3563       ConsumeToken();
3564   }
3565   return false;
3566 }
3567 
3568 /// Checks if the token is a valid map-type.
3569 /// FIXME: It will return an OpenMPMapModifierKind if that's what it parses.
3570 static OpenMPMapClauseKind isMapType(Parser &P) {
3571   Token Tok = P.getCurToken();
3572   // The map-type token can be either an identifier or the C++ delete keyword.
3573   if (!Tok.isOneOf(tok::identifier, tok::kw_delete))
3574     return OMPC_MAP_unknown;
3575   Preprocessor &PP = P.getPreprocessor();
3576   OpenMPMapClauseKind MapType =
3577       static_cast<OpenMPMapClauseKind>(getOpenMPSimpleClauseType(
3578           OMPC_map, PP.getSpelling(Tok), P.getLangOpts().OpenMP));
3579   return MapType;
3580 }
3581 
3582 /// Parse map-type in map clause.
3583 /// map([ [map-type-modifier[,] [map-type-modifier[,] ...] map-type : ] list)
3584 /// where, map-type ::= to | from | tofrom | alloc | release | delete
3585 static void parseMapType(Parser &P, Parser::OpenMPVarListDataTy &Data) {
3586   Token Tok = P.getCurToken();
3587   if (Tok.is(tok::colon)) {
3588     P.Diag(Tok, diag::err_omp_map_type_missing);
3589     return;
3590   }
3591   Data.ExtraModifier = isMapType(P);
3592   if (Data.ExtraModifier == OMPC_MAP_unknown)
3593     P.Diag(Tok, diag::err_omp_unknown_map_type);
3594   P.ConsumeToken();
3595 }
3596 
3597 /// Parses simple expression in parens for single-expression clauses of OpenMP
3598 /// constructs.
3599 ExprResult Parser::ParseOpenMPIteratorsExpr() {
3600   assert(Tok.is(tok::identifier) && PP.getSpelling(Tok) == "iterator" &&
3601          "Expected 'iterator' token.");
3602   SourceLocation IteratorKwLoc = ConsumeToken();
3603 
3604   BalancedDelimiterTracker T(*this, tok::l_paren, tok::annot_pragma_openmp_end);
3605   if (T.expectAndConsume(diag::err_expected_lparen_after, "iterator"))
3606     return ExprError();
3607 
3608   SourceLocation LLoc = T.getOpenLocation();
3609   SmallVector<Sema::OMPIteratorData, 4> Data;
3610   while (Tok.isNot(tok::r_paren) && Tok.isNot(tok::annot_pragma_openmp_end)) {
3611     // Check if the type parsing is required.
3612     ParsedType IteratorType;
3613     if (Tok.isNot(tok::identifier) || NextToken().isNot(tok::equal)) {
3614       // identifier '=' is not found - parse type.
3615       TypeResult TR = ParseTypeName();
3616       if (TR.isInvalid()) {
3617         T.skipToEnd();
3618         return ExprError();
3619       }
3620       IteratorType = TR.get();
3621     }
3622 
3623     // Parse identifier.
3624     IdentifierInfo *II = nullptr;
3625     SourceLocation IdLoc;
3626     if (Tok.is(tok::identifier)) {
3627       II = Tok.getIdentifierInfo();
3628       IdLoc = ConsumeToken();
3629     } else {
3630       Diag(Tok, diag::err_expected_unqualified_id) << 0;
3631     }
3632 
3633     // Parse '='.
3634     SourceLocation AssignLoc;
3635     if (Tok.is(tok::equal))
3636       AssignLoc = ConsumeToken();
3637     else
3638       Diag(Tok, diag::err_omp_expected_equal_in_iterator);
3639 
3640     // Parse range-specification - <begin> ':' <end> [ ':' <step> ]
3641     ColonProtectionRAIIObject ColonRAII(*this);
3642     // Parse <begin>
3643     SourceLocation Loc = Tok.getLocation();
3644     ExprResult LHS = ParseCastExpression(AnyCastExpr);
3645     ExprResult Begin = Actions.CorrectDelayedTyposInExpr(
3646         ParseRHSOfBinaryExpression(LHS, prec::Conditional));
3647     Begin = Actions.ActOnFinishFullExpr(Begin.get(), Loc,
3648                                         /*DiscardedValue=*/false);
3649     // Parse ':'.
3650     SourceLocation ColonLoc;
3651     if (Tok.is(tok::colon))
3652       ColonLoc = ConsumeToken();
3653 
3654     // Parse <end>
3655     Loc = Tok.getLocation();
3656     LHS = ParseCastExpression(AnyCastExpr);
3657     ExprResult End = Actions.CorrectDelayedTyposInExpr(
3658         ParseRHSOfBinaryExpression(LHS, prec::Conditional));
3659     End = Actions.ActOnFinishFullExpr(End.get(), Loc,
3660                                       /*DiscardedValue=*/false);
3661 
3662     SourceLocation SecColonLoc;
3663     ExprResult Step;
3664     // Parse optional step.
3665     if (Tok.is(tok::colon)) {
3666       // Parse ':'
3667       SecColonLoc = ConsumeToken();
3668       // Parse <step>
3669       Loc = Tok.getLocation();
3670       LHS = ParseCastExpression(AnyCastExpr);
3671       Step = Actions.CorrectDelayedTyposInExpr(
3672           ParseRHSOfBinaryExpression(LHS, prec::Conditional));
3673       Step = Actions.ActOnFinishFullExpr(Step.get(), Loc,
3674                                          /*DiscardedValue=*/false);
3675     }
3676 
3677     // Parse ',' or ')'
3678     if (Tok.isNot(tok::comma) && Tok.isNot(tok::r_paren))
3679       Diag(Tok, diag::err_omp_expected_punc_after_iterator);
3680     if (Tok.is(tok::comma))
3681       ConsumeToken();
3682 
3683     Sema::OMPIteratorData &D = Data.emplace_back();
3684     D.DeclIdent = II;
3685     D.DeclIdentLoc = IdLoc;
3686     D.Type = IteratorType;
3687     D.AssignLoc = AssignLoc;
3688     D.ColonLoc = ColonLoc;
3689     D.SecColonLoc = SecColonLoc;
3690     D.Range.Begin = Begin.get();
3691     D.Range.End = End.get();
3692     D.Range.Step = Step.get();
3693   }
3694 
3695   // Parse ')'.
3696   SourceLocation RLoc = Tok.getLocation();
3697   if (!T.consumeClose())
3698     RLoc = T.getCloseLocation();
3699 
3700   return Actions.ActOnOMPIteratorExpr(getCurScope(), IteratorKwLoc, LLoc, RLoc,
3701                                       Data);
3702 }
3703 
3704 /// Parses clauses with list.
3705 bool Parser::ParseOpenMPVarList(OpenMPDirectiveKind DKind,
3706                                 OpenMPClauseKind Kind,
3707                                 SmallVectorImpl<Expr *> &Vars,
3708                                 OpenMPVarListDataTy &Data) {
3709   UnqualifiedId UnqualifiedReductionId;
3710   bool InvalidReductionId = false;
3711   bool IsInvalidMapperModifier = false;
3712 
3713   // Parse '('.
3714   BalancedDelimiterTracker T(*this, tok::l_paren, tok::annot_pragma_openmp_end);
3715   if (T.expectAndConsume(diag::err_expected_lparen_after,
3716                          getOpenMPClauseName(Kind).data()))
3717     return true;
3718 
3719   bool HasIterator = false;
3720   bool NeedRParenForLinear = false;
3721   BalancedDelimiterTracker LinearT(*this, tok::l_paren,
3722                                    tok::annot_pragma_openmp_end);
3723   // Handle reduction-identifier for reduction clause.
3724   if (Kind == OMPC_reduction || Kind == OMPC_task_reduction ||
3725       Kind == OMPC_in_reduction) {
3726     Data.ExtraModifier = OMPC_REDUCTION_unknown;
3727     if (Kind == OMPC_reduction && getLangOpts().OpenMP >= 50 &&
3728         (Tok.is(tok::identifier) || Tok.is(tok::kw_default)) &&
3729         NextToken().is(tok::comma)) {
3730       // Parse optional reduction modifier.
3731       Data.ExtraModifier = getOpenMPSimpleClauseType(Kind, PP.getSpelling(Tok),
3732                                                      getLangOpts().OpenMP);
3733       Data.ExtraModifierLoc = Tok.getLocation();
3734       ConsumeToken();
3735       assert(Tok.is(tok::comma) && "Expected comma.");
3736       (void)ConsumeToken();
3737     }
3738     ColonProtectionRAIIObject ColonRAII(*this);
3739     if (getLangOpts().CPlusPlus)
3740       ParseOptionalCXXScopeSpecifier(Data.ReductionOrMapperIdScopeSpec,
3741                                      /*ObjectType=*/nullptr,
3742                                      /*ObjectHadErrors=*/false,
3743                                      /*EnteringContext=*/false);
3744     InvalidReductionId = ParseReductionId(
3745         *this, Data.ReductionOrMapperIdScopeSpec, UnqualifiedReductionId);
3746     if (InvalidReductionId) {
3747       SkipUntil(tok::colon, tok::r_paren, tok::annot_pragma_openmp_end,
3748                 StopBeforeMatch);
3749     }
3750     if (Tok.is(tok::colon))
3751       Data.ColonLoc = ConsumeToken();
3752     else
3753       Diag(Tok, diag::warn_pragma_expected_colon) << "reduction identifier";
3754     if (!InvalidReductionId)
3755       Data.ReductionOrMapperId =
3756           Actions.GetNameFromUnqualifiedId(UnqualifiedReductionId);
3757   } else if (Kind == OMPC_depend) {
3758     if (getLangOpts().OpenMP >= 50) {
3759       if (Tok.is(tok::identifier) && PP.getSpelling(Tok) == "iterator") {
3760         // Handle optional dependence modifier.
3761         // iterator(iterators-definition)
3762         // where iterators-definition is iterator-specifier [,
3763         // iterators-definition ]
3764         // where iterator-specifier is [ iterator-type ] identifier =
3765         // range-specification
3766         HasIterator = true;
3767         EnterScope(Scope::OpenMPDirectiveScope | Scope::DeclScope);
3768         ExprResult IteratorRes = ParseOpenMPIteratorsExpr();
3769         Data.DepModOrTailExpr = IteratorRes.get();
3770         // Parse ','
3771         ExpectAndConsume(tok::comma);
3772       }
3773     }
3774     // Handle dependency type for depend clause.
3775     ColonProtectionRAIIObject ColonRAII(*this);
3776     Data.ExtraModifier = getOpenMPSimpleClauseType(
3777         Kind, Tok.is(tok::identifier) ? PP.getSpelling(Tok) : "",
3778         getLangOpts().OpenMP);
3779     Data.ExtraModifierLoc = Tok.getLocation();
3780     if (Data.ExtraModifier == OMPC_DEPEND_unknown) {
3781       SkipUntil(tok::colon, tok::r_paren, tok::annot_pragma_openmp_end,
3782                 StopBeforeMatch);
3783     } else {
3784       ConsumeToken();
3785       // Special processing for depend(source) clause.
3786       if (DKind == OMPD_ordered && Data.ExtraModifier == OMPC_DEPEND_source) {
3787         // Parse ')'.
3788         T.consumeClose();
3789         return false;
3790       }
3791     }
3792     if (Tok.is(tok::colon)) {
3793       Data.ColonLoc = ConsumeToken();
3794     } else {
3795       Diag(Tok, DKind == OMPD_ordered ? diag::warn_pragma_expected_colon_r_paren
3796                                       : diag::warn_pragma_expected_colon)
3797           << "dependency type";
3798     }
3799   } else if (Kind == OMPC_linear) {
3800     // Try to parse modifier if any.
3801     Data.ExtraModifier = OMPC_LINEAR_val;
3802     if (Tok.is(tok::identifier) && PP.LookAhead(0).is(tok::l_paren)) {
3803       Data.ExtraModifier = getOpenMPSimpleClauseType(Kind, PP.getSpelling(Tok),
3804                                                      getLangOpts().OpenMP);
3805       Data.ExtraModifierLoc = ConsumeToken();
3806       LinearT.consumeOpen();
3807       NeedRParenForLinear = true;
3808     }
3809   } else if (Kind == OMPC_lastprivate) {
3810     // Try to parse modifier if any.
3811     Data.ExtraModifier = OMPC_LASTPRIVATE_unknown;
3812     // Conditional modifier allowed only in OpenMP 5.0 and not supported in
3813     // distribute and taskloop based directives.
3814     if ((getLangOpts().OpenMP >= 50 && !isOpenMPDistributeDirective(DKind) &&
3815          !isOpenMPTaskLoopDirective(DKind)) &&
3816         Tok.is(tok::identifier) && PP.LookAhead(0).is(tok::colon)) {
3817       Data.ExtraModifier = getOpenMPSimpleClauseType(Kind, PP.getSpelling(Tok),
3818                                                      getLangOpts().OpenMP);
3819       Data.ExtraModifierLoc = Tok.getLocation();
3820       ConsumeToken();
3821       assert(Tok.is(tok::colon) && "Expected colon.");
3822       Data.ColonLoc = ConsumeToken();
3823     }
3824   } else if (Kind == OMPC_map) {
3825     // Handle map type for map clause.
3826     ColonProtectionRAIIObject ColonRAII(*this);
3827 
3828     // The first identifier may be a list item, a map-type or a
3829     // map-type-modifier. The map-type can also be delete which has the same
3830     // spelling of the C++ delete keyword.
3831     Data.ExtraModifier = OMPC_MAP_unknown;
3832     Data.ExtraModifierLoc = Tok.getLocation();
3833 
3834     // Check for presence of a colon in the map clause.
3835     TentativeParsingAction TPA(*this);
3836     bool ColonPresent = false;
3837     if (SkipUntil(tok::colon, tok::r_paren, tok::annot_pragma_openmp_end,
3838                   StopBeforeMatch)) {
3839       if (Tok.is(tok::colon))
3840         ColonPresent = true;
3841     }
3842     TPA.Revert();
3843     // Only parse map-type-modifier[s] and map-type if a colon is present in
3844     // the map clause.
3845     if (ColonPresent) {
3846       IsInvalidMapperModifier = parseMapTypeModifiers(Data);
3847       if (!IsInvalidMapperModifier)
3848         parseMapType(*this, Data);
3849       else
3850         SkipUntil(tok::colon, tok::annot_pragma_openmp_end, StopBeforeMatch);
3851     }
3852     if (Data.ExtraModifier == OMPC_MAP_unknown) {
3853       Data.ExtraModifier = OMPC_MAP_tofrom;
3854       Data.IsMapTypeImplicit = true;
3855     }
3856 
3857     if (Tok.is(tok::colon))
3858       Data.ColonLoc = ConsumeToken();
3859   } else if (Kind == OMPC_to || Kind == OMPC_from) {
3860     while (Tok.is(tok::identifier)) {
3861       auto Modifier =
3862           static_cast<OpenMPMotionModifierKind>(getOpenMPSimpleClauseType(
3863               Kind, PP.getSpelling(Tok), getLangOpts().OpenMP));
3864       if (Modifier == OMPC_MOTION_MODIFIER_unknown)
3865         break;
3866       Data.MotionModifiers.push_back(Modifier);
3867       Data.MotionModifiersLoc.push_back(Tok.getLocation());
3868       ConsumeToken();
3869       if (Modifier == OMPC_MOTION_MODIFIER_mapper) {
3870         IsInvalidMapperModifier = parseMapperModifier(Data);
3871         if (IsInvalidMapperModifier)
3872           break;
3873       }
3874       // OpenMP < 5.1 doesn't permit a ',' or additional modifiers.
3875       if (getLangOpts().OpenMP < 51)
3876         break;
3877       // OpenMP 5.1 accepts an optional ',' even if the next character is ':'.
3878       // TODO: Is that intentional?
3879       if (Tok.is(tok::comma))
3880         ConsumeToken();
3881     }
3882     if (!Data.MotionModifiers.empty() && Tok.isNot(tok::colon)) {
3883       if (!IsInvalidMapperModifier) {
3884         if (getLangOpts().OpenMP < 51)
3885           Diag(Tok, diag::warn_pragma_expected_colon) << ")";
3886         else
3887           Diag(Tok, diag::warn_pragma_expected_colon) << "motion modifier";
3888       }
3889       SkipUntil(tok::colon, tok::r_paren, tok::annot_pragma_openmp_end,
3890                 StopBeforeMatch);
3891     }
3892     // OpenMP 5.1 permits a ':' even without a preceding modifier.  TODO: Is
3893     // that intentional?
3894     if ((!Data.MotionModifiers.empty() || getLangOpts().OpenMP >= 51) &&
3895         Tok.is(tok::colon))
3896       Data.ColonLoc = ConsumeToken();
3897   } else if (Kind == OMPC_allocate ||
3898              (Kind == OMPC_affinity && Tok.is(tok::identifier) &&
3899               PP.getSpelling(Tok) == "iterator")) {
3900     // Handle optional allocator expression followed by colon delimiter.
3901     ColonProtectionRAIIObject ColonRAII(*this);
3902     TentativeParsingAction TPA(*this);
3903     // OpenMP 5.0, 2.10.1, task Construct.
3904     // where aff-modifier is one of the following:
3905     // iterator(iterators-definition)
3906     ExprResult Tail;
3907     if (Kind == OMPC_allocate) {
3908       Tail = ParseAssignmentExpression();
3909     } else {
3910       HasIterator = true;
3911       EnterScope(Scope::OpenMPDirectiveScope | Scope::DeclScope);
3912       Tail = ParseOpenMPIteratorsExpr();
3913     }
3914     Tail = Actions.CorrectDelayedTyposInExpr(Tail);
3915     Tail = Actions.ActOnFinishFullExpr(Tail.get(), T.getOpenLocation(),
3916                                        /*DiscardedValue=*/false);
3917     if (Tail.isUsable()) {
3918       if (Tok.is(tok::colon)) {
3919         Data.DepModOrTailExpr = Tail.get();
3920         Data.ColonLoc = ConsumeToken();
3921         TPA.Commit();
3922       } else {
3923         // Colon not found, parse only list of variables.
3924         TPA.Revert();
3925       }
3926     } else {
3927       // Parsing was unsuccessfull, revert and skip to the end of clause or
3928       // directive.
3929       TPA.Revert();
3930       SkipUntil(tok::comma, tok::r_paren, tok::annot_pragma_openmp_end,
3931                 StopBeforeMatch);
3932     }
3933   }
3934 
3935   bool IsComma =
3936       (Kind != OMPC_reduction && Kind != OMPC_task_reduction &&
3937        Kind != OMPC_in_reduction && Kind != OMPC_depend && Kind != OMPC_map) ||
3938       (Kind == OMPC_reduction && !InvalidReductionId) ||
3939       (Kind == OMPC_map && Data.ExtraModifier != OMPC_MAP_unknown) ||
3940       (Kind == OMPC_depend && Data.ExtraModifier != OMPC_DEPEND_unknown);
3941   const bool MayHaveTail = (Kind == OMPC_linear || Kind == OMPC_aligned);
3942   while (IsComma || (Tok.isNot(tok::r_paren) && Tok.isNot(tok::colon) &&
3943                      Tok.isNot(tok::annot_pragma_openmp_end))) {
3944     ParseScope OMPListScope(this, Scope::OpenMPDirectiveScope);
3945     ColonProtectionRAIIObject ColonRAII(*this, MayHaveTail);
3946     // Parse variable
3947     ExprResult VarExpr =
3948         Actions.CorrectDelayedTyposInExpr(ParseAssignmentExpression());
3949     if (VarExpr.isUsable()) {
3950       Vars.push_back(VarExpr.get());
3951     } else {
3952       SkipUntil(tok::comma, tok::r_paren, tok::annot_pragma_openmp_end,
3953                 StopBeforeMatch);
3954     }
3955     // Skip ',' if any
3956     IsComma = Tok.is(tok::comma);
3957     if (IsComma)
3958       ConsumeToken();
3959     else if (Tok.isNot(tok::r_paren) &&
3960              Tok.isNot(tok::annot_pragma_openmp_end) &&
3961              (!MayHaveTail || Tok.isNot(tok::colon)))
3962       Diag(Tok, diag::err_omp_expected_punc)
3963           << ((Kind == OMPC_flush) ? getOpenMPDirectiveName(OMPD_flush)
3964                                    : getOpenMPClauseName(Kind))
3965           << (Kind == OMPC_flush);
3966   }
3967 
3968   // Parse ')' for linear clause with modifier.
3969   if (NeedRParenForLinear)
3970     LinearT.consumeClose();
3971 
3972   // Parse ':' linear-step (or ':' alignment).
3973   const bool MustHaveTail = MayHaveTail && Tok.is(tok::colon);
3974   if (MustHaveTail) {
3975     Data.ColonLoc = Tok.getLocation();
3976     SourceLocation ELoc = ConsumeToken();
3977     ExprResult Tail = ParseAssignmentExpression();
3978     Tail =
3979         Actions.ActOnFinishFullExpr(Tail.get(), ELoc, /*DiscardedValue*/ false);
3980     if (Tail.isUsable())
3981       Data.DepModOrTailExpr = Tail.get();
3982     else
3983       SkipUntil(tok::comma, tok::r_paren, tok::annot_pragma_openmp_end,
3984                 StopBeforeMatch);
3985   }
3986 
3987   // Parse ')'.
3988   Data.RLoc = Tok.getLocation();
3989   if (!T.consumeClose())
3990     Data.RLoc = T.getCloseLocation();
3991   // Exit from scope when the iterator is used in depend clause.
3992   if (HasIterator)
3993     ExitScope();
3994   return (Kind != OMPC_depend && Kind != OMPC_map && Vars.empty()) ||
3995          (MustHaveTail && !Data.DepModOrTailExpr) || InvalidReductionId ||
3996          IsInvalidMapperModifier;
3997 }
3998 
3999 /// Parsing of OpenMP clause 'private', 'firstprivate', 'lastprivate',
4000 /// 'shared', 'copyin', 'copyprivate', 'flush', 'reduction', 'task_reduction',
4001 /// 'in_reduction', 'nontemporal', 'exclusive' or 'inclusive'.
4002 ///
4003 ///    private-clause:
4004 ///       'private' '(' list ')'
4005 ///    firstprivate-clause:
4006 ///       'firstprivate' '(' list ')'
4007 ///    lastprivate-clause:
4008 ///       'lastprivate' '(' list ')'
4009 ///    shared-clause:
4010 ///       'shared' '(' list ')'
4011 ///    linear-clause:
4012 ///       'linear' '(' linear-list [ ':' linear-step ] ')'
4013 ///    aligned-clause:
4014 ///       'aligned' '(' list [ ':' alignment ] ')'
4015 ///    reduction-clause:
4016 ///       'reduction' '(' [ modifier ',' ] reduction-identifier ':' list ')'
4017 ///    task_reduction-clause:
4018 ///       'task_reduction' '(' reduction-identifier ':' list ')'
4019 ///    in_reduction-clause:
4020 ///       'in_reduction' '(' reduction-identifier ':' list ')'
4021 ///    copyprivate-clause:
4022 ///       'copyprivate' '(' list ')'
4023 ///    flush-clause:
4024 ///       'flush' '(' list ')'
4025 ///    depend-clause:
4026 ///       'depend' '(' in | out | inout : list | source ')'
4027 ///    map-clause:
4028 ///       'map' '(' [ [ always [,] ] [ close [,] ]
4029 ///          [ mapper '(' mapper-identifier ')' [,] ]
4030 ///          to | from | tofrom | alloc | release | delete ':' ] list ')';
4031 ///    to-clause:
4032 ///       'to' '(' [ mapper '(' mapper-identifier ')' ':' ] list ')'
4033 ///    from-clause:
4034 ///       'from' '(' [ mapper '(' mapper-identifier ')' ':' ] list ')'
4035 ///    use_device_ptr-clause:
4036 ///       'use_device_ptr' '(' list ')'
4037 ///    use_device_addr-clause:
4038 ///       'use_device_addr' '(' list ')'
4039 ///    is_device_ptr-clause:
4040 ///       'is_device_ptr' '(' list ')'
4041 ///    allocate-clause:
4042 ///       'allocate' '(' [ allocator ':' ] list ')'
4043 ///    nontemporal-clause:
4044 ///       'nontemporal' '(' list ')'
4045 ///    inclusive-clause:
4046 ///       'inclusive' '(' list ')'
4047 ///    exclusive-clause:
4048 ///       'exclusive' '(' list ')'
4049 ///
4050 /// For 'linear' clause linear-list may have the following forms:
4051 ///  list
4052 ///  modifier(list)
4053 /// where modifier is 'val' (C) or 'ref', 'val' or 'uval'(C++).
4054 OMPClause *Parser::ParseOpenMPVarListClause(OpenMPDirectiveKind DKind,
4055                                             OpenMPClauseKind Kind,
4056                                             bool ParseOnly) {
4057   SourceLocation Loc = Tok.getLocation();
4058   SourceLocation LOpen = ConsumeToken();
4059   SmallVector<Expr *, 4> Vars;
4060   OpenMPVarListDataTy Data;
4061 
4062   if (ParseOpenMPVarList(DKind, Kind, Vars, Data))
4063     return nullptr;
4064 
4065   if (ParseOnly)
4066     return nullptr;
4067   OMPVarListLocTy Locs(Loc, LOpen, Data.RLoc);
4068   return Actions.ActOnOpenMPVarListClause(
4069       Kind, Vars, Data.DepModOrTailExpr, Locs, Data.ColonLoc,
4070       Data.ReductionOrMapperIdScopeSpec, Data.ReductionOrMapperId,
4071       Data.ExtraModifier, Data.MapTypeModifiers, Data.MapTypeModifiersLoc,
4072       Data.IsMapTypeImplicit, Data.ExtraModifierLoc, Data.MotionModifiers,
4073       Data.MotionModifiersLoc);
4074 }
4075