xref: /freebsd/contrib/llvm-project/clang/lib/Parse/ParseOpenMP.cpp (revision cfd6422a5217410fbd66f7a7a8a64d9d85e61229)
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/UniqueVector.h"
25 #include "llvm/Frontend/OpenMP/OMPContext.h"
26 
27 using namespace clang;
28 using namespace llvm::omp;
29 
30 //===----------------------------------------------------------------------===//
31 // OpenMP declarative directives.
32 //===----------------------------------------------------------------------===//
33 
34 namespace {
35 enum OpenMPDirectiveKindEx {
36   OMPD_cancellation = llvm::omp::Directive_enumSize + 1,
37   OMPD_data,
38   OMPD_declare,
39   OMPD_end,
40   OMPD_end_declare,
41   OMPD_enter,
42   OMPD_exit,
43   OMPD_point,
44   OMPD_reduction,
45   OMPD_target_enter,
46   OMPD_target_exit,
47   OMPD_update,
48   OMPD_distribute_parallel,
49   OMPD_teams_distribute_parallel,
50   OMPD_target_teams_distribute_parallel,
51   OMPD_mapper,
52   OMPD_variant,
53   OMPD_begin,
54   OMPD_begin_declare,
55 };
56 
57 // Helper to unify the enum class OpenMPDirectiveKind with its extension
58 // the OpenMPDirectiveKindEx enum which allows to use them together as if they
59 // are unsigned values.
60 struct OpenMPDirectiveKindExWrapper {
61   OpenMPDirectiveKindExWrapper(unsigned Value) : Value(Value) {}
62   OpenMPDirectiveKindExWrapper(OpenMPDirectiveKind DK) : Value(unsigned(DK)) {}
63   bool operator==(OpenMPDirectiveKind V) const { return Value == unsigned(V); }
64   bool operator!=(OpenMPDirectiveKind V) const { return Value != unsigned(V); }
65   bool operator<(OpenMPDirectiveKind V) const { return Value < unsigned(V); }
66   operator unsigned() const { return Value; }
67   operator OpenMPDirectiveKind() const { return OpenMPDirectiveKind(Value); }
68   unsigned Value;
69 };
70 
71 class DeclDirectiveListParserHelper final {
72   SmallVector<Expr *, 4> Identifiers;
73   Parser *P;
74   OpenMPDirectiveKind Kind;
75 
76 public:
77   DeclDirectiveListParserHelper(Parser *P, OpenMPDirectiveKind Kind)
78       : P(P), Kind(Kind) {}
79   void operator()(CXXScopeSpec &SS, DeclarationNameInfo NameInfo) {
80     ExprResult Res = P->getActions().ActOnOpenMPIdExpression(
81         P->getCurScope(), SS, NameInfo, Kind);
82     if (Res.isUsable())
83       Identifiers.push_back(Res.get());
84   }
85   llvm::ArrayRef<Expr *> getIdentifiers() const { return Identifiers; }
86 };
87 } // namespace
88 
89 // Map token string to extended OMP token kind that are
90 // OpenMPDirectiveKind + OpenMPDirectiveKindEx.
91 static unsigned getOpenMPDirectiveKindEx(StringRef S) {
92   OpenMPDirectiveKindExWrapper DKind = getOpenMPDirectiveKind(S);
93   if (DKind != OMPD_unknown)
94     return DKind;
95 
96   return llvm::StringSwitch<OpenMPDirectiveKindExWrapper>(S)
97       .Case("cancellation", OMPD_cancellation)
98       .Case("data", OMPD_data)
99       .Case("declare", OMPD_declare)
100       .Case("end", OMPD_end)
101       .Case("enter", OMPD_enter)
102       .Case("exit", OMPD_exit)
103       .Case("point", OMPD_point)
104       .Case("reduction", OMPD_reduction)
105       .Case("update", OMPD_update)
106       .Case("mapper", OMPD_mapper)
107       .Case("variant", OMPD_variant)
108       .Case("begin", OMPD_begin)
109       .Default(OMPD_unknown);
110 }
111 
112 static OpenMPDirectiveKindExWrapper parseOpenMPDirectiveKind(Parser &P) {
113   // Array of foldings: F[i][0] F[i][1] ===> F[i][2].
114   // E.g.: OMPD_for OMPD_simd ===> OMPD_for_simd
115   // TODO: add other combined directives in topological order.
116   static const OpenMPDirectiveKindExWrapper F[][3] = {
117       {OMPD_begin, OMPD_declare, OMPD_begin_declare},
118       {OMPD_end, OMPD_declare, OMPD_end_declare},
119       {OMPD_cancellation, OMPD_point, OMPD_cancellation_point},
120       {OMPD_declare, OMPD_reduction, OMPD_declare_reduction},
121       {OMPD_declare, OMPD_mapper, OMPD_declare_mapper},
122       {OMPD_declare, OMPD_simd, OMPD_declare_simd},
123       {OMPD_declare, OMPD_target, OMPD_declare_target},
124       {OMPD_declare, OMPD_variant, OMPD_declare_variant},
125       {OMPD_begin_declare, OMPD_variant, OMPD_begin_declare_variant},
126       {OMPD_end_declare, OMPD_variant, OMPD_end_declare_variant},
127       {OMPD_distribute, OMPD_parallel, OMPD_distribute_parallel},
128       {OMPD_distribute_parallel, OMPD_for, OMPD_distribute_parallel_for},
129       {OMPD_distribute_parallel_for, OMPD_simd,
130        OMPD_distribute_parallel_for_simd},
131       {OMPD_distribute, OMPD_simd, OMPD_distribute_simd},
132       {OMPD_end_declare, OMPD_target, OMPD_end_declare_target},
133       {OMPD_target, OMPD_data, OMPD_target_data},
134       {OMPD_target, OMPD_enter, OMPD_target_enter},
135       {OMPD_target, OMPD_exit, OMPD_target_exit},
136       {OMPD_target, OMPD_update, OMPD_target_update},
137       {OMPD_target_enter, OMPD_data, OMPD_target_enter_data},
138       {OMPD_target_exit, OMPD_data, OMPD_target_exit_data},
139       {OMPD_for, OMPD_simd, OMPD_for_simd},
140       {OMPD_parallel, OMPD_for, OMPD_parallel_for},
141       {OMPD_parallel_for, OMPD_simd, OMPD_parallel_for_simd},
142       {OMPD_parallel, OMPD_sections, OMPD_parallel_sections},
143       {OMPD_taskloop, OMPD_simd, OMPD_taskloop_simd},
144       {OMPD_target, OMPD_parallel, OMPD_target_parallel},
145       {OMPD_target, OMPD_simd, OMPD_target_simd},
146       {OMPD_target_parallel, OMPD_for, OMPD_target_parallel_for},
147       {OMPD_target_parallel_for, OMPD_simd, OMPD_target_parallel_for_simd},
148       {OMPD_teams, OMPD_distribute, OMPD_teams_distribute},
149       {OMPD_teams_distribute, OMPD_simd, OMPD_teams_distribute_simd},
150       {OMPD_teams_distribute, OMPD_parallel, OMPD_teams_distribute_parallel},
151       {OMPD_teams_distribute_parallel, OMPD_for,
152        OMPD_teams_distribute_parallel_for},
153       {OMPD_teams_distribute_parallel_for, OMPD_simd,
154        OMPD_teams_distribute_parallel_for_simd},
155       {OMPD_target, OMPD_teams, OMPD_target_teams},
156       {OMPD_target_teams, OMPD_distribute, OMPD_target_teams_distribute},
157       {OMPD_target_teams_distribute, OMPD_parallel,
158        OMPD_target_teams_distribute_parallel},
159       {OMPD_target_teams_distribute, OMPD_simd,
160        OMPD_target_teams_distribute_simd},
161       {OMPD_target_teams_distribute_parallel, OMPD_for,
162        OMPD_target_teams_distribute_parallel_for},
163       {OMPD_target_teams_distribute_parallel_for, OMPD_simd,
164        OMPD_target_teams_distribute_parallel_for_simd},
165       {OMPD_master, OMPD_taskloop, OMPD_master_taskloop},
166       {OMPD_master_taskloop, OMPD_simd, OMPD_master_taskloop_simd},
167       {OMPD_parallel, OMPD_master, OMPD_parallel_master},
168       {OMPD_parallel_master, OMPD_taskloop, OMPD_parallel_master_taskloop},
169       {OMPD_parallel_master_taskloop, OMPD_simd,
170        OMPD_parallel_master_taskloop_simd}};
171   enum { CancellationPoint = 0, DeclareReduction = 1, TargetData = 2 };
172   Token Tok = P.getCurToken();
173   OpenMPDirectiveKindExWrapper DKind =
174       Tok.isAnnotation()
175           ? static_cast<unsigned>(OMPD_unknown)
176           : getOpenMPDirectiveKindEx(P.getPreprocessor().getSpelling(Tok));
177   if (DKind == OMPD_unknown)
178     return OMPD_unknown;
179 
180   for (unsigned I = 0; I < llvm::array_lengthof(F); ++I) {
181     if (DKind != F[I][0])
182       continue;
183 
184     Tok = P.getPreprocessor().LookAhead(0);
185     OpenMPDirectiveKindExWrapper SDKind =
186         Tok.isAnnotation()
187             ? static_cast<unsigned>(OMPD_unknown)
188             : getOpenMPDirectiveKindEx(P.getPreprocessor().getSpelling(Tok));
189     if (SDKind == OMPD_unknown)
190       continue;
191 
192     if (SDKind == F[I][1]) {
193       P.ConsumeToken();
194       DKind = F[I][2];
195     }
196   }
197   return unsigned(DKind) < llvm::omp::Directive_enumSize
198              ? static_cast<OpenMPDirectiveKind>(DKind)
199              : OMPD_unknown;
200 }
201 
202 static DeclarationName parseOpenMPReductionId(Parser &P) {
203   Token Tok = P.getCurToken();
204   Sema &Actions = P.getActions();
205   OverloadedOperatorKind OOK = OO_None;
206   // Allow to use 'operator' keyword for C++ operators
207   bool WithOperator = false;
208   if (Tok.is(tok::kw_operator)) {
209     P.ConsumeToken();
210     Tok = P.getCurToken();
211     WithOperator = true;
212   }
213   switch (Tok.getKind()) {
214   case tok::plus: // '+'
215     OOK = OO_Plus;
216     break;
217   case tok::minus: // '-'
218     OOK = OO_Minus;
219     break;
220   case tok::star: // '*'
221     OOK = OO_Star;
222     break;
223   case tok::amp: // '&'
224     OOK = OO_Amp;
225     break;
226   case tok::pipe: // '|'
227     OOK = OO_Pipe;
228     break;
229   case tok::caret: // '^'
230     OOK = OO_Caret;
231     break;
232   case tok::ampamp: // '&&'
233     OOK = OO_AmpAmp;
234     break;
235   case tok::pipepipe: // '||'
236     OOK = OO_PipePipe;
237     break;
238   case tok::identifier: // identifier
239     if (!WithOperator)
240       break;
241     LLVM_FALLTHROUGH;
242   default:
243     P.Diag(Tok.getLocation(), diag::err_omp_expected_reduction_identifier);
244     P.SkipUntil(tok::colon, tok::r_paren, tok::annot_pragma_openmp_end,
245                 Parser::StopBeforeMatch);
246     return DeclarationName();
247   }
248   P.ConsumeToken();
249   auto &DeclNames = Actions.getASTContext().DeclarationNames;
250   return OOK == OO_None ? DeclNames.getIdentifier(Tok.getIdentifierInfo())
251                         : DeclNames.getCXXOperatorName(OOK);
252 }
253 
254 /// Parse 'omp declare reduction' construct.
255 ///
256 ///       declare-reduction-directive:
257 ///        annot_pragma_openmp 'declare' 'reduction'
258 ///        '(' <reduction_id> ':' <type> {',' <type>} ':' <expression> ')'
259 ///        ['initializer' '(' ('omp_priv' '=' <expression>)|<function_call> ')']
260 ///        annot_pragma_openmp_end
261 /// <reduction_id> is either a base language identifier or one of the following
262 /// operators: '+', '-', '*', '&', '|', '^', '&&' and '||'.
263 ///
264 Parser::DeclGroupPtrTy
265 Parser::ParseOpenMPDeclareReductionDirective(AccessSpecifier AS) {
266   // Parse '('.
267   BalancedDelimiterTracker T(*this, tok::l_paren, tok::annot_pragma_openmp_end);
268   if (T.expectAndConsume(
269           diag::err_expected_lparen_after,
270           getOpenMPDirectiveName(OMPD_declare_reduction).data())) {
271     SkipUntil(tok::annot_pragma_openmp_end, StopBeforeMatch);
272     return DeclGroupPtrTy();
273   }
274 
275   DeclarationName Name = parseOpenMPReductionId(*this);
276   if (Name.isEmpty() && Tok.is(tok::annot_pragma_openmp_end))
277     return DeclGroupPtrTy();
278 
279   // Consume ':'.
280   bool IsCorrect = !ExpectAndConsume(tok::colon);
281 
282   if (!IsCorrect && Tok.is(tok::annot_pragma_openmp_end))
283     return DeclGroupPtrTy();
284 
285   IsCorrect = IsCorrect && !Name.isEmpty();
286 
287   if (Tok.is(tok::colon) || Tok.is(tok::annot_pragma_openmp_end)) {
288     Diag(Tok.getLocation(), diag::err_expected_type);
289     IsCorrect = false;
290   }
291 
292   if (!IsCorrect && Tok.is(tok::annot_pragma_openmp_end))
293     return DeclGroupPtrTy();
294 
295   SmallVector<std::pair<QualType, SourceLocation>, 8> ReductionTypes;
296   // Parse list of types until ':' token.
297   do {
298     ColonProtectionRAIIObject ColonRAII(*this);
299     SourceRange Range;
300     TypeResult TR =
301         ParseTypeName(&Range, DeclaratorContext::PrototypeContext, AS);
302     if (TR.isUsable()) {
303       QualType ReductionType =
304           Actions.ActOnOpenMPDeclareReductionType(Range.getBegin(), TR);
305       if (!ReductionType.isNull()) {
306         ReductionTypes.push_back(
307             std::make_pair(ReductionType, Range.getBegin()));
308       }
309     } else {
310       SkipUntil(tok::comma, tok::colon, tok::annot_pragma_openmp_end,
311                 StopBeforeMatch);
312     }
313 
314     if (Tok.is(tok::colon) || Tok.is(tok::annot_pragma_openmp_end))
315       break;
316 
317     // Consume ','.
318     if (ExpectAndConsume(tok::comma)) {
319       IsCorrect = false;
320       if (Tok.is(tok::annot_pragma_openmp_end)) {
321         Diag(Tok.getLocation(), diag::err_expected_type);
322         return DeclGroupPtrTy();
323       }
324     }
325   } while (Tok.isNot(tok::annot_pragma_openmp_end));
326 
327   if (ReductionTypes.empty()) {
328     SkipUntil(tok::annot_pragma_openmp_end, StopBeforeMatch);
329     return DeclGroupPtrTy();
330   }
331 
332   if (!IsCorrect && Tok.is(tok::annot_pragma_openmp_end))
333     return DeclGroupPtrTy();
334 
335   // Consume ':'.
336   if (ExpectAndConsume(tok::colon))
337     IsCorrect = false;
338 
339   if (Tok.is(tok::annot_pragma_openmp_end)) {
340     Diag(Tok.getLocation(), diag::err_expected_expression);
341     return DeclGroupPtrTy();
342   }
343 
344   DeclGroupPtrTy DRD = Actions.ActOnOpenMPDeclareReductionDirectiveStart(
345       getCurScope(), Actions.getCurLexicalContext(), Name, ReductionTypes, AS);
346 
347   // Parse <combiner> expression and then parse initializer if any for each
348   // correct type.
349   unsigned I = 0, E = ReductionTypes.size();
350   for (Decl *D : DRD.get()) {
351     TentativeParsingAction TPA(*this);
352     ParseScope OMPDRScope(this, Scope::FnScope | Scope::DeclScope |
353                                     Scope::CompoundStmtScope |
354                                     Scope::OpenMPDirectiveScope);
355     // Parse <combiner> expression.
356     Actions.ActOnOpenMPDeclareReductionCombinerStart(getCurScope(), D);
357     ExprResult CombinerResult = Actions.ActOnFinishFullExpr(
358         ParseExpression().get(), D->getLocation(), /*DiscardedValue*/ false);
359     Actions.ActOnOpenMPDeclareReductionCombinerEnd(D, CombinerResult.get());
360 
361     if (CombinerResult.isInvalid() && Tok.isNot(tok::r_paren) &&
362         Tok.isNot(tok::annot_pragma_openmp_end)) {
363       TPA.Commit();
364       IsCorrect = false;
365       break;
366     }
367     IsCorrect = !T.consumeClose() && IsCorrect && CombinerResult.isUsable();
368     ExprResult InitializerResult;
369     if (Tok.isNot(tok::annot_pragma_openmp_end)) {
370       // Parse <initializer> expression.
371       if (Tok.is(tok::identifier) &&
372           Tok.getIdentifierInfo()->isStr("initializer")) {
373         ConsumeToken();
374       } else {
375         Diag(Tok.getLocation(), diag::err_expected) << "'initializer'";
376         TPA.Commit();
377         IsCorrect = false;
378         break;
379       }
380       // Parse '('.
381       BalancedDelimiterTracker T(*this, tok::l_paren,
382                                  tok::annot_pragma_openmp_end);
383       IsCorrect =
384           !T.expectAndConsume(diag::err_expected_lparen_after, "initializer") &&
385           IsCorrect;
386       if (Tok.isNot(tok::annot_pragma_openmp_end)) {
387         ParseScope OMPDRScope(this, Scope::FnScope | Scope::DeclScope |
388                                         Scope::CompoundStmtScope |
389                                         Scope::OpenMPDirectiveScope);
390         // Parse expression.
391         VarDecl *OmpPrivParm =
392             Actions.ActOnOpenMPDeclareReductionInitializerStart(getCurScope(),
393                                                                 D);
394         // Check if initializer is omp_priv <init_expr> or something else.
395         if (Tok.is(tok::identifier) &&
396             Tok.getIdentifierInfo()->isStr("omp_priv")) {
397           ConsumeToken();
398           ParseOpenMPReductionInitializerForDecl(OmpPrivParm);
399         } else {
400           InitializerResult = Actions.ActOnFinishFullExpr(
401               ParseAssignmentExpression().get(), D->getLocation(),
402               /*DiscardedValue*/ false);
403         }
404         Actions.ActOnOpenMPDeclareReductionInitializerEnd(
405             D, InitializerResult.get(), OmpPrivParm);
406         if (InitializerResult.isInvalid() && Tok.isNot(tok::r_paren) &&
407             Tok.isNot(tok::annot_pragma_openmp_end)) {
408           TPA.Commit();
409           IsCorrect = false;
410           break;
411         }
412         IsCorrect =
413             !T.consumeClose() && IsCorrect && !InitializerResult.isInvalid();
414       }
415     }
416 
417     ++I;
418     // Revert parsing if not the last type, otherwise accept it, we're done with
419     // parsing.
420     if (I != E)
421       TPA.Revert();
422     else
423       TPA.Commit();
424   }
425   return Actions.ActOnOpenMPDeclareReductionDirectiveEnd(getCurScope(), DRD,
426                                                          IsCorrect);
427 }
428 
429 void Parser::ParseOpenMPReductionInitializerForDecl(VarDecl *OmpPrivParm) {
430   // Parse declarator '=' initializer.
431   // If a '==' or '+=' is found, suggest a fixit to '='.
432   if (isTokenEqualOrEqualTypo()) {
433     ConsumeToken();
434 
435     if (Tok.is(tok::code_completion)) {
436       Actions.CodeCompleteInitializer(getCurScope(), OmpPrivParm);
437       Actions.FinalizeDeclaration(OmpPrivParm);
438       cutOffParsing();
439       return;
440     }
441 
442     PreferredType.enterVariableInit(Tok.getLocation(), OmpPrivParm);
443     ExprResult Init = ParseInitializer();
444 
445     if (Init.isInvalid()) {
446       SkipUntil(tok::r_paren, tok::annot_pragma_openmp_end, StopBeforeMatch);
447       Actions.ActOnInitializerError(OmpPrivParm);
448     } else {
449       Actions.AddInitializerToDecl(OmpPrivParm, Init.get(),
450                                    /*DirectInit=*/false);
451     }
452   } else if (Tok.is(tok::l_paren)) {
453     // Parse C++ direct initializer: '(' expression-list ')'
454     BalancedDelimiterTracker T(*this, tok::l_paren);
455     T.consumeOpen();
456 
457     ExprVector Exprs;
458     CommaLocsTy CommaLocs;
459 
460     SourceLocation LParLoc = T.getOpenLocation();
461     auto RunSignatureHelp = [this, OmpPrivParm, LParLoc, &Exprs]() {
462       QualType PreferredType = Actions.ProduceConstructorSignatureHelp(
463           getCurScope(), OmpPrivParm->getType()->getCanonicalTypeInternal(),
464           OmpPrivParm->getLocation(), Exprs, LParLoc);
465       CalledSignatureHelp = true;
466       return PreferredType;
467     };
468     if (ParseExpressionList(Exprs, CommaLocs, [&] {
469           PreferredType.enterFunctionArgument(Tok.getLocation(),
470                                               RunSignatureHelp);
471         })) {
472       if (PP.isCodeCompletionReached() && !CalledSignatureHelp)
473         RunSignatureHelp();
474       Actions.ActOnInitializerError(OmpPrivParm);
475       SkipUntil(tok::r_paren, tok::annot_pragma_openmp_end, StopBeforeMatch);
476     } else {
477       // Match the ')'.
478       SourceLocation RLoc = Tok.getLocation();
479       if (!T.consumeClose())
480         RLoc = T.getCloseLocation();
481 
482       assert(!Exprs.empty() && Exprs.size() - 1 == CommaLocs.size() &&
483              "Unexpected number of commas!");
484 
485       ExprResult Initializer =
486           Actions.ActOnParenListExpr(T.getOpenLocation(), RLoc, Exprs);
487       Actions.AddInitializerToDecl(OmpPrivParm, Initializer.get(),
488                                    /*DirectInit=*/true);
489     }
490   } else if (getLangOpts().CPlusPlus11 && Tok.is(tok::l_brace)) {
491     // Parse C++0x braced-init-list.
492     Diag(Tok, diag::warn_cxx98_compat_generalized_initializer_lists);
493 
494     ExprResult Init(ParseBraceInitializer());
495 
496     if (Init.isInvalid()) {
497       Actions.ActOnInitializerError(OmpPrivParm);
498     } else {
499       Actions.AddInitializerToDecl(OmpPrivParm, Init.get(),
500                                    /*DirectInit=*/true);
501     }
502   } else {
503     Actions.ActOnUninitializedDecl(OmpPrivParm);
504   }
505 }
506 
507 /// Parses 'omp declare mapper' directive.
508 ///
509 ///       declare-mapper-directive:
510 ///         annot_pragma_openmp 'declare' 'mapper' '(' [<mapper-identifier> ':']
511 ///         <type> <var> ')' [<clause>[[,] <clause>] ... ]
512 ///         annot_pragma_openmp_end
513 /// <mapper-identifier> and <var> are base language identifiers.
514 ///
515 Parser::DeclGroupPtrTy
516 Parser::ParseOpenMPDeclareMapperDirective(AccessSpecifier AS) {
517   bool IsCorrect = true;
518   // Parse '('
519   BalancedDelimiterTracker T(*this, tok::l_paren, tok::annot_pragma_openmp_end);
520   if (T.expectAndConsume(diag::err_expected_lparen_after,
521                          getOpenMPDirectiveName(OMPD_declare_mapper).data())) {
522     SkipUntil(tok::annot_pragma_openmp_end, StopBeforeMatch);
523     return DeclGroupPtrTy();
524   }
525 
526   // Parse <mapper-identifier>
527   auto &DeclNames = Actions.getASTContext().DeclarationNames;
528   DeclarationName MapperId;
529   if (PP.LookAhead(0).is(tok::colon)) {
530     if (Tok.isNot(tok::identifier) && Tok.isNot(tok::kw_default)) {
531       Diag(Tok.getLocation(), diag::err_omp_mapper_illegal_identifier);
532       IsCorrect = false;
533     } else {
534       MapperId = DeclNames.getIdentifier(Tok.getIdentifierInfo());
535     }
536     ConsumeToken();
537     // Consume ':'.
538     ExpectAndConsume(tok::colon);
539   } else {
540     // If no mapper identifier is provided, its name is "default" by default
541     MapperId =
542         DeclNames.getIdentifier(&Actions.getASTContext().Idents.get("default"));
543   }
544 
545   if (!IsCorrect && Tok.is(tok::annot_pragma_openmp_end))
546     return DeclGroupPtrTy();
547 
548   // Parse <type> <var>
549   DeclarationName VName;
550   QualType MapperType;
551   SourceRange Range;
552   TypeResult ParsedType = parseOpenMPDeclareMapperVarDecl(Range, VName, AS);
553   if (ParsedType.isUsable())
554     MapperType =
555         Actions.ActOnOpenMPDeclareMapperType(Range.getBegin(), ParsedType);
556   if (MapperType.isNull())
557     IsCorrect = false;
558   if (!IsCorrect) {
559     SkipUntil(tok::annot_pragma_openmp_end, Parser::StopBeforeMatch);
560     return DeclGroupPtrTy();
561   }
562 
563   // Consume ')'.
564   IsCorrect &= !T.consumeClose();
565   if (!IsCorrect) {
566     SkipUntil(tok::annot_pragma_openmp_end, Parser::StopBeforeMatch);
567     return DeclGroupPtrTy();
568   }
569 
570   // Enter scope.
571   OMPDeclareMapperDecl *DMD = Actions.ActOnOpenMPDeclareMapperDirectiveStart(
572       getCurScope(), Actions.getCurLexicalContext(), MapperId, MapperType,
573       Range.getBegin(), VName, AS);
574   DeclarationNameInfo DirName;
575   SourceLocation Loc = Tok.getLocation();
576   unsigned ScopeFlags = Scope::FnScope | Scope::DeclScope |
577                         Scope::CompoundStmtScope | Scope::OpenMPDirectiveScope;
578   ParseScope OMPDirectiveScope(this, ScopeFlags);
579   Actions.StartOpenMPDSABlock(OMPD_declare_mapper, DirName, getCurScope(), Loc);
580 
581   // Add the mapper variable declaration.
582   Actions.ActOnOpenMPDeclareMapperDirectiveVarDecl(
583       DMD, getCurScope(), MapperType, Range.getBegin(), VName);
584 
585   // Parse map clauses.
586   SmallVector<OMPClause *, 6> Clauses;
587   while (Tok.isNot(tok::annot_pragma_openmp_end)) {
588     OpenMPClauseKind CKind = Tok.isAnnotation()
589                                  ? OMPC_unknown
590                                  : getOpenMPClauseKind(PP.getSpelling(Tok));
591     Actions.StartOpenMPClause(CKind);
592     OMPClause *Clause =
593         ParseOpenMPClause(OMPD_declare_mapper, CKind, Clauses.size() == 0);
594     if (Clause)
595       Clauses.push_back(Clause);
596     else
597       IsCorrect = false;
598     // Skip ',' if any.
599     if (Tok.is(tok::comma))
600       ConsumeToken();
601     Actions.EndOpenMPClause();
602   }
603   if (Clauses.empty()) {
604     Diag(Tok, diag::err_omp_expected_clause)
605         << getOpenMPDirectiveName(OMPD_declare_mapper);
606     IsCorrect = false;
607   }
608 
609   // Exit scope.
610   Actions.EndOpenMPDSABlock(nullptr);
611   OMPDirectiveScope.Exit();
612 
613   DeclGroupPtrTy DGP =
614       Actions.ActOnOpenMPDeclareMapperDirectiveEnd(DMD, getCurScope(), Clauses);
615   if (!IsCorrect)
616     return DeclGroupPtrTy();
617   return DGP;
618 }
619 
620 TypeResult Parser::parseOpenMPDeclareMapperVarDecl(SourceRange &Range,
621                                                    DeclarationName &Name,
622                                                    AccessSpecifier AS) {
623   // Parse the common declaration-specifiers piece.
624   Parser::DeclSpecContext DSC = Parser::DeclSpecContext::DSC_type_specifier;
625   DeclSpec DS(AttrFactory);
626   ParseSpecifierQualifierList(DS, AS, DSC);
627 
628   // Parse the declarator.
629   DeclaratorContext Context = DeclaratorContext::PrototypeContext;
630   Declarator DeclaratorInfo(DS, Context);
631   ParseDeclarator(DeclaratorInfo);
632   Range = DeclaratorInfo.getSourceRange();
633   if (DeclaratorInfo.getIdentifier() == nullptr) {
634     Diag(Tok.getLocation(), diag::err_omp_mapper_expected_declarator);
635     return true;
636   }
637   Name = Actions.GetNameForDeclarator(DeclaratorInfo).getName();
638 
639   return Actions.ActOnOpenMPDeclareMapperVarDecl(getCurScope(), DeclaratorInfo);
640 }
641 
642 namespace {
643 /// RAII that recreates function context for correct parsing of clauses of
644 /// 'declare simd' construct.
645 /// OpenMP, 2.8.2 declare simd Construct
646 /// The expressions appearing in the clauses of this directive are evaluated in
647 /// the scope of the arguments of the function declaration or definition.
648 class FNContextRAII final {
649   Parser &P;
650   Sema::CXXThisScopeRAII *ThisScope;
651   Parser::MultiParseScope Scopes;
652   bool HasFunScope = false;
653   FNContextRAII() = delete;
654   FNContextRAII(const FNContextRAII &) = delete;
655   FNContextRAII &operator=(const FNContextRAII &) = delete;
656 
657 public:
658   FNContextRAII(Parser &P, Parser::DeclGroupPtrTy Ptr) : P(P), Scopes(P) {
659     Decl *D = *Ptr.get().begin();
660     NamedDecl *ND = dyn_cast<NamedDecl>(D);
661     RecordDecl *RD = dyn_cast_or_null<RecordDecl>(D->getDeclContext());
662     Sema &Actions = P.getActions();
663 
664     // Allow 'this' within late-parsed attributes.
665     ThisScope = new Sema::CXXThisScopeRAII(Actions, RD, Qualifiers(),
666                                            ND && ND->isCXXInstanceMember());
667 
668     // If the Decl is templatized, add template parameters to scope.
669     // FIXME: Track CurTemplateDepth?
670     P.ReenterTemplateScopes(Scopes, D);
671 
672     // If the Decl is on a function, add function parameters to the scope.
673     if (D->isFunctionOrFunctionTemplate()) {
674       HasFunScope = true;
675       Scopes.Enter(Scope::FnScope | Scope::DeclScope |
676                    Scope::CompoundStmtScope);
677       Actions.ActOnReenterFunctionContext(Actions.getCurScope(), D);
678     }
679   }
680   ~FNContextRAII() {
681     if (HasFunScope)
682       P.getActions().ActOnExitFunctionContext();
683     delete ThisScope;
684   }
685 };
686 } // namespace
687 
688 /// Parses clauses for 'declare simd' directive.
689 ///    clause:
690 ///      'inbranch' | 'notinbranch'
691 ///      'simdlen' '(' <expr> ')'
692 ///      { 'uniform' '(' <argument_list> ')' }
693 ///      { 'aligned '(' <argument_list> [ ':' <alignment> ] ')' }
694 ///      { 'linear '(' <argument_list> [ ':' <step> ] ')' }
695 static bool parseDeclareSimdClauses(
696     Parser &P, OMPDeclareSimdDeclAttr::BranchStateTy &BS, ExprResult &SimdLen,
697     SmallVectorImpl<Expr *> &Uniforms, SmallVectorImpl<Expr *> &Aligneds,
698     SmallVectorImpl<Expr *> &Alignments, SmallVectorImpl<Expr *> &Linears,
699     SmallVectorImpl<unsigned> &LinModifiers, SmallVectorImpl<Expr *> &Steps) {
700   SourceRange BSRange;
701   const Token &Tok = P.getCurToken();
702   bool IsError = false;
703   while (Tok.isNot(tok::annot_pragma_openmp_end)) {
704     if (Tok.isNot(tok::identifier))
705       break;
706     OMPDeclareSimdDeclAttr::BranchStateTy Out;
707     IdentifierInfo *II = Tok.getIdentifierInfo();
708     StringRef ClauseName = II->getName();
709     // Parse 'inranch|notinbranch' clauses.
710     if (OMPDeclareSimdDeclAttr::ConvertStrToBranchStateTy(ClauseName, Out)) {
711       if (BS != OMPDeclareSimdDeclAttr::BS_Undefined && BS != Out) {
712         P.Diag(Tok, diag::err_omp_declare_simd_inbranch_notinbranch)
713             << ClauseName
714             << OMPDeclareSimdDeclAttr::ConvertBranchStateTyToStr(BS) << BSRange;
715         IsError = true;
716       }
717       BS = Out;
718       BSRange = SourceRange(Tok.getLocation(), Tok.getEndLoc());
719       P.ConsumeToken();
720     } else if (ClauseName.equals("simdlen")) {
721       if (SimdLen.isUsable()) {
722         P.Diag(Tok, diag::err_omp_more_one_clause)
723             << getOpenMPDirectiveName(OMPD_declare_simd) << ClauseName << 0;
724         IsError = true;
725       }
726       P.ConsumeToken();
727       SourceLocation RLoc;
728       SimdLen = P.ParseOpenMPParensExpr(ClauseName, RLoc);
729       if (SimdLen.isInvalid())
730         IsError = true;
731     } else {
732       OpenMPClauseKind CKind = getOpenMPClauseKind(ClauseName);
733       if (CKind == OMPC_uniform || CKind == OMPC_aligned ||
734           CKind == OMPC_linear) {
735         Parser::OpenMPVarListDataTy Data;
736         SmallVectorImpl<Expr *> *Vars = &Uniforms;
737         if (CKind == OMPC_aligned) {
738           Vars = &Aligneds;
739         } else if (CKind == OMPC_linear) {
740           Data.ExtraModifier = OMPC_LINEAR_val;
741           Vars = &Linears;
742         }
743 
744         P.ConsumeToken();
745         if (P.ParseOpenMPVarList(OMPD_declare_simd,
746                                  getOpenMPClauseKind(ClauseName), *Vars, Data))
747           IsError = true;
748         if (CKind == OMPC_aligned) {
749           Alignments.append(Aligneds.size() - Alignments.size(),
750                             Data.DepModOrTailExpr);
751         } else if (CKind == OMPC_linear) {
752           assert(0 <= Data.ExtraModifier &&
753                  Data.ExtraModifier <= OMPC_LINEAR_unknown &&
754                  "Unexpected linear modifier.");
755           if (P.getActions().CheckOpenMPLinearModifier(
756                   static_cast<OpenMPLinearClauseKind>(Data.ExtraModifier),
757                   Data.ExtraModifierLoc))
758             Data.ExtraModifier = OMPC_LINEAR_val;
759           LinModifiers.append(Linears.size() - LinModifiers.size(),
760                               Data.ExtraModifier);
761           Steps.append(Linears.size() - Steps.size(), Data.DepModOrTailExpr);
762         }
763       } else
764         // TODO: add parsing of other clauses.
765         break;
766     }
767     // Skip ',' if any.
768     if (Tok.is(tok::comma))
769       P.ConsumeToken();
770   }
771   return IsError;
772 }
773 
774 /// Parse clauses for '#pragma omp declare simd'.
775 Parser::DeclGroupPtrTy
776 Parser::ParseOMPDeclareSimdClauses(Parser::DeclGroupPtrTy Ptr,
777                                    CachedTokens &Toks, SourceLocation Loc) {
778   PP.EnterToken(Tok, /*IsReinject*/ true);
779   PP.EnterTokenStream(Toks, /*DisableMacroExpansion=*/true,
780                       /*IsReinject*/ true);
781   // Consume the previously pushed token.
782   ConsumeAnyToken(/*ConsumeCodeCompletionTok=*/true);
783   ConsumeAnyToken(/*ConsumeCodeCompletionTok=*/true);
784 
785   FNContextRAII FnContext(*this, Ptr);
786   OMPDeclareSimdDeclAttr::BranchStateTy BS =
787       OMPDeclareSimdDeclAttr::BS_Undefined;
788   ExprResult Simdlen;
789   SmallVector<Expr *, 4> Uniforms;
790   SmallVector<Expr *, 4> Aligneds;
791   SmallVector<Expr *, 4> Alignments;
792   SmallVector<Expr *, 4> Linears;
793   SmallVector<unsigned, 4> LinModifiers;
794   SmallVector<Expr *, 4> Steps;
795   bool IsError =
796       parseDeclareSimdClauses(*this, BS, Simdlen, Uniforms, Aligneds,
797                               Alignments, Linears, LinModifiers, Steps);
798   skipUntilPragmaOpenMPEnd(OMPD_declare_simd);
799   // Skip the last annot_pragma_openmp_end.
800   SourceLocation EndLoc = ConsumeAnnotationToken();
801   if (IsError)
802     return Ptr;
803   return Actions.ActOnOpenMPDeclareSimdDirective(
804       Ptr, BS, Simdlen.get(), Uniforms, Aligneds, Alignments, Linears,
805       LinModifiers, Steps, SourceRange(Loc, EndLoc));
806 }
807 
808 namespace {
809 /// Constant used in the diagnostics to distinguish the levels in an OpenMP
810 /// contexts: selector-set={selector(trait, ...), ...}, ....
811 enum OMPContextLvl {
812   CONTEXT_SELECTOR_SET_LVL = 0,
813   CONTEXT_SELECTOR_LVL = 1,
814   CONTEXT_TRAIT_LVL = 2,
815 };
816 
817 static StringRef stringLiteralParser(Parser &P) {
818   ExprResult Res = P.ParseStringLiteralExpression(true);
819   return Res.isUsable() ? Res.getAs<StringLiteral>()->getString() : "";
820 }
821 
822 static StringRef getNameFromIdOrString(Parser &P, Token &Tok,
823                                        OMPContextLvl Lvl) {
824   if (Tok.is(tok::identifier)) {
825     llvm::SmallString<16> Buffer;
826     StringRef Name = P.getPreprocessor().getSpelling(Tok, Buffer);
827     (void)P.ConsumeToken();
828     return Name;
829   }
830 
831   if (tok::isStringLiteral(Tok.getKind()))
832     return stringLiteralParser(P);
833 
834   P.Diag(Tok.getLocation(),
835          diag::warn_omp_declare_variant_string_literal_or_identifier)
836       << Lvl;
837   return "";
838 }
839 
840 static bool checkForDuplicates(Parser &P, StringRef Name,
841                                SourceLocation NameLoc,
842                                llvm::StringMap<SourceLocation> &Seen,
843                                OMPContextLvl Lvl) {
844   auto Res = Seen.try_emplace(Name, NameLoc);
845   if (Res.second)
846     return false;
847 
848   // Each trait-set-selector-name, trait-selector-name and trait-name can
849   // only be specified once.
850   P.Diag(NameLoc, diag::warn_omp_declare_variant_ctx_mutiple_use)
851       << Lvl << Name;
852   P.Diag(Res.first->getValue(), diag::note_omp_declare_variant_ctx_used_here)
853       << Lvl << Name;
854   return true;
855 }
856 } // namespace
857 
858 void Parser::parseOMPTraitPropertyKind(
859     OMPTraitProperty &TIProperty, llvm::omp::TraitSet Set,
860     llvm::omp::TraitSelector Selector, llvm::StringMap<SourceLocation> &Seen) {
861   TIProperty.Kind = TraitProperty::invalid;
862 
863   SourceLocation NameLoc = Tok.getLocation();
864   StringRef Name =
865       getNameFromIdOrString(*this, Tok, CONTEXT_TRAIT_LVL);
866   if (Name.empty()) {
867     Diag(Tok.getLocation(), diag::note_omp_declare_variant_ctx_options)
868         << CONTEXT_TRAIT_LVL << listOpenMPContextTraitProperties(Set, Selector);
869     return;
870   }
871 
872   TIProperty.Kind = getOpenMPContextTraitPropertyKind(Set, Name);
873   if (TIProperty.Kind != TraitProperty::invalid) {
874     if (checkForDuplicates(*this, Name, NameLoc, Seen, CONTEXT_TRAIT_LVL))
875       TIProperty.Kind = TraitProperty::invalid;
876     return;
877   }
878 
879   // It follows diagnosis and helping notes.
880   // FIXME: We should move the diagnosis string generation into libFrontend.
881   Diag(NameLoc, diag::warn_omp_declare_variant_ctx_not_a_property)
882       << Name << getOpenMPContextTraitSelectorName(Selector)
883       << getOpenMPContextTraitSetName(Set);
884 
885   TraitSet SetForName = getOpenMPContextTraitSetKind(Name);
886   if (SetForName != TraitSet::invalid) {
887     Diag(NameLoc, diag::note_omp_declare_variant_ctx_is_a)
888         << Name << CONTEXT_SELECTOR_SET_LVL << CONTEXT_TRAIT_LVL;
889     Diag(NameLoc, diag::note_omp_declare_variant_ctx_try)
890         << Name << "<selector-name>"
891         << "(<property-name>)";
892     return;
893   }
894   TraitSelector SelectorForName = getOpenMPContextTraitSelectorKind(Name);
895   if (SelectorForName != TraitSelector::invalid) {
896     Diag(NameLoc, diag::note_omp_declare_variant_ctx_is_a)
897         << Name << CONTEXT_SELECTOR_LVL << CONTEXT_TRAIT_LVL;
898     bool AllowsTraitScore = false;
899     bool RequiresProperty = false;
900     isValidTraitSelectorForTraitSet(
901         SelectorForName, getOpenMPContextTraitSetForSelector(SelectorForName),
902         AllowsTraitScore, RequiresProperty);
903     Diag(NameLoc, diag::note_omp_declare_variant_ctx_try)
904         << getOpenMPContextTraitSetName(
905                getOpenMPContextTraitSetForSelector(SelectorForName))
906         << Name << (RequiresProperty ? "(<property-name>)" : "");
907     return;
908   }
909   for (const auto &PotentialSet :
910        {TraitSet::construct, TraitSet::user, TraitSet::implementation,
911         TraitSet::device}) {
912     TraitProperty PropertyForName =
913         getOpenMPContextTraitPropertyKind(PotentialSet, Name);
914     if (PropertyForName == TraitProperty::invalid)
915       continue;
916     Diag(NameLoc, diag::note_omp_declare_variant_ctx_try)
917         << getOpenMPContextTraitSetName(
918                getOpenMPContextTraitSetForProperty(PropertyForName))
919         << getOpenMPContextTraitSelectorName(
920                getOpenMPContextTraitSelectorForProperty(PropertyForName))
921         << ("(" + Name + ")").str();
922     return;
923   }
924   Diag(NameLoc, diag::note_omp_declare_variant_ctx_options)
925       << CONTEXT_TRAIT_LVL << listOpenMPContextTraitProperties(Set, Selector);
926 }
927 
928 static bool checkExtensionProperty(Parser &P, SourceLocation Loc,
929                                    OMPTraitProperty &TIProperty,
930                                    OMPTraitSelector &TISelector,
931                                    llvm::StringMap<SourceLocation> &Seen) {
932   assert(TISelector.Kind ==
933              llvm::omp::TraitSelector::implementation_extension &&
934          "Only for extension properties, e.g., "
935          "`implementation={extension(PROPERTY)}`");
936   if (TIProperty.Kind == TraitProperty::invalid)
937     return false;
938 
939   auto IsMatchExtension = [](OMPTraitProperty &TP) {
940     return (TP.Kind ==
941                 llvm::omp::TraitProperty::implementation_extension_match_all ||
942             TP.Kind ==
943                 llvm::omp::TraitProperty::implementation_extension_match_any ||
944             TP.Kind ==
945                 llvm::omp::TraitProperty::implementation_extension_match_none);
946   };
947 
948   if (IsMatchExtension(TIProperty)) {
949     for (OMPTraitProperty &SeenProp : TISelector.Properties)
950       if (IsMatchExtension(SeenProp)) {
951         P.Diag(Loc, diag::err_omp_variant_ctx_second_match_extension);
952         StringRef SeenName =
953             llvm::omp::getOpenMPContextTraitPropertyName(SeenProp.Kind);
954         SourceLocation SeenLoc = Seen[SeenName];
955         P.Diag(SeenLoc, diag::note_omp_declare_variant_ctx_used_here)
956             << CONTEXT_TRAIT_LVL << SeenName;
957         return false;
958       }
959     return true;
960   }
961 
962   llvm_unreachable("Unknown extension property!");
963 }
964 
965 void Parser::parseOMPContextProperty(OMPTraitSelector &TISelector,
966                                      llvm::omp::TraitSet Set,
967                                      llvm::StringMap<SourceLocation> &Seen) {
968   assert(TISelector.Kind != TraitSelector::user_condition &&
969          "User conditions are special properties not handled here!");
970 
971   SourceLocation PropertyLoc = Tok.getLocation();
972   OMPTraitProperty TIProperty;
973   parseOMPTraitPropertyKind(TIProperty, Set, TISelector.Kind, Seen);
974 
975   if (TISelector.Kind == llvm::omp::TraitSelector::implementation_extension)
976     if (!checkExtensionProperty(*this, Tok.getLocation(), TIProperty,
977                                 TISelector, Seen))
978       TIProperty.Kind = TraitProperty::invalid;
979 
980   // If we have an invalid property here we already issued a warning.
981   if (TIProperty.Kind == TraitProperty::invalid) {
982     if (PropertyLoc != Tok.getLocation())
983       Diag(Tok.getLocation(), diag::note_omp_declare_variant_ctx_continue_here)
984           << CONTEXT_TRAIT_LVL;
985     return;
986   }
987 
988   if (isValidTraitPropertyForTraitSetAndSelector(TIProperty.Kind,
989                                                  TISelector.Kind, Set)) {
990 
991     // If we make it here the property, selector, set, score, condition, ... are
992     // all valid (or have been corrected). Thus we can record the property.
993     TISelector.Properties.push_back(TIProperty);
994     return;
995   }
996 
997   Diag(PropertyLoc, diag::warn_omp_ctx_incompatible_property_for_selector)
998       << getOpenMPContextTraitPropertyName(TIProperty.Kind)
999       << getOpenMPContextTraitSelectorName(TISelector.Kind)
1000       << getOpenMPContextTraitSetName(Set);
1001   Diag(PropertyLoc, diag::note_omp_ctx_compatible_set_and_selector_for_property)
1002       << getOpenMPContextTraitPropertyName(TIProperty.Kind)
1003       << getOpenMPContextTraitSelectorName(
1004              getOpenMPContextTraitSelectorForProperty(TIProperty.Kind))
1005       << getOpenMPContextTraitSetName(
1006              getOpenMPContextTraitSetForProperty(TIProperty.Kind));
1007   Diag(Tok.getLocation(), diag::note_omp_declare_variant_ctx_continue_here)
1008       << CONTEXT_TRAIT_LVL;
1009 }
1010 
1011 void Parser::parseOMPTraitSelectorKind(
1012     OMPTraitSelector &TISelector, llvm::omp::TraitSet Set,
1013     llvm::StringMap<SourceLocation> &Seen) {
1014   TISelector.Kind = TraitSelector::invalid;
1015 
1016   SourceLocation NameLoc = Tok.getLocation();
1017   StringRef Name = getNameFromIdOrString(*this, Tok, CONTEXT_SELECTOR_LVL
1018                     );
1019   if (Name.empty()) {
1020     Diag(Tok.getLocation(), diag::note_omp_declare_variant_ctx_options)
1021         << CONTEXT_SELECTOR_LVL << listOpenMPContextTraitSelectors(Set);
1022     return;
1023   }
1024 
1025   TISelector.Kind = getOpenMPContextTraitSelectorKind(Name);
1026   if (TISelector.Kind != TraitSelector::invalid) {
1027     if (checkForDuplicates(*this, Name, NameLoc, Seen, CONTEXT_SELECTOR_LVL))
1028       TISelector.Kind = TraitSelector::invalid;
1029     return;
1030   }
1031 
1032   // It follows diagnosis and helping notes.
1033   Diag(NameLoc, diag::warn_omp_declare_variant_ctx_not_a_selector)
1034       << Name << getOpenMPContextTraitSetName(Set);
1035 
1036   TraitSet SetForName = getOpenMPContextTraitSetKind(Name);
1037   if (SetForName != TraitSet::invalid) {
1038     Diag(NameLoc, diag::note_omp_declare_variant_ctx_is_a)
1039         << Name << CONTEXT_SELECTOR_SET_LVL << CONTEXT_SELECTOR_LVL;
1040     Diag(NameLoc, diag::note_omp_declare_variant_ctx_try)
1041         << Name << "<selector-name>"
1042         << "<property-name>";
1043     return;
1044   }
1045   for (const auto &PotentialSet :
1046        {TraitSet::construct, TraitSet::user, TraitSet::implementation,
1047         TraitSet::device}) {
1048     TraitProperty PropertyForName =
1049         getOpenMPContextTraitPropertyKind(PotentialSet, Name);
1050     if (PropertyForName == TraitProperty::invalid)
1051       continue;
1052     Diag(NameLoc, diag::note_omp_declare_variant_ctx_is_a)
1053         << Name << CONTEXT_TRAIT_LVL << CONTEXT_SELECTOR_LVL;
1054     Diag(NameLoc, diag::note_omp_declare_variant_ctx_try)
1055         << getOpenMPContextTraitSetName(
1056                getOpenMPContextTraitSetForProperty(PropertyForName))
1057         << getOpenMPContextTraitSelectorName(
1058                getOpenMPContextTraitSelectorForProperty(PropertyForName))
1059         << ("(" + Name + ")").str();
1060     return;
1061   }
1062   Diag(NameLoc, diag::note_omp_declare_variant_ctx_options)
1063       << CONTEXT_SELECTOR_LVL << listOpenMPContextTraitSelectors(Set);
1064 }
1065 
1066 /// Parse optional 'score' '(' <expr> ')' ':'.
1067 static ExprResult parseContextScore(Parser &P) {
1068   ExprResult ScoreExpr;
1069   llvm::SmallString<16> Buffer;
1070   StringRef SelectorName =
1071       P.getPreprocessor().getSpelling(P.getCurToken(), Buffer);
1072   if (!SelectorName.equals("score"))
1073     return ScoreExpr;
1074   (void)P.ConsumeToken();
1075   SourceLocation RLoc;
1076   ScoreExpr = P.ParseOpenMPParensExpr(SelectorName, RLoc);
1077   // Parse ':'
1078   if (P.getCurToken().is(tok::colon))
1079     (void)P.ConsumeAnyToken();
1080   else
1081     P.Diag(P.getCurToken(), diag::warn_omp_declare_variant_expected)
1082         << "':'"
1083         << "score expression";
1084   return ScoreExpr;
1085 }
1086 
1087 /// Parses an OpenMP context selector.
1088 ///
1089 /// <trait-selector-name> ['('[<trait-score>] <trait-property> [, <t-p>]* ')']
1090 void Parser::parseOMPContextSelector(
1091     OMPTraitSelector &TISelector, llvm::omp::TraitSet Set,
1092     llvm::StringMap<SourceLocation> &SeenSelectors) {
1093   unsigned short OuterPC = ParenCount;
1094 
1095   // If anything went wrong we issue an error or warning and then skip the rest
1096   // of the selector. However, commas are ambiguous so we look for the nesting
1097   // of parentheses here as well.
1098   auto FinishSelector = [OuterPC, this]() -> void {
1099     bool Done = false;
1100     while (!Done) {
1101       while (!SkipUntil({tok::r_brace, tok::r_paren, tok::comma,
1102                          tok::annot_pragma_openmp_end},
1103                         StopBeforeMatch))
1104         ;
1105       if (Tok.is(tok::r_paren) && OuterPC > ParenCount)
1106         (void)ConsumeParen();
1107       if (OuterPC <= ParenCount) {
1108         Done = true;
1109         break;
1110       }
1111       if (!Tok.is(tok::comma) && !Tok.is(tok::r_paren)) {
1112         Done = true;
1113         break;
1114       }
1115       (void)ConsumeAnyToken();
1116     }
1117     Diag(Tok.getLocation(), diag::note_omp_declare_variant_ctx_continue_here)
1118         << CONTEXT_SELECTOR_LVL;
1119   };
1120 
1121   SourceLocation SelectorLoc = Tok.getLocation();
1122   parseOMPTraitSelectorKind(TISelector, Set, SeenSelectors);
1123   if (TISelector.Kind == TraitSelector::invalid)
1124     return FinishSelector();
1125 
1126   bool AllowsTraitScore = false;
1127   bool RequiresProperty = false;
1128   if (!isValidTraitSelectorForTraitSet(TISelector.Kind, Set, AllowsTraitScore,
1129                                        RequiresProperty)) {
1130     Diag(SelectorLoc, diag::warn_omp_ctx_incompatible_selector_for_set)
1131         << getOpenMPContextTraitSelectorName(TISelector.Kind)
1132         << getOpenMPContextTraitSetName(Set);
1133     Diag(SelectorLoc, diag::note_omp_ctx_compatible_set_for_selector)
1134         << getOpenMPContextTraitSelectorName(TISelector.Kind)
1135         << getOpenMPContextTraitSetName(
1136                getOpenMPContextTraitSetForSelector(TISelector.Kind))
1137         << RequiresProperty;
1138     return FinishSelector();
1139   }
1140 
1141   if (!RequiresProperty) {
1142     TISelector.Properties.push_back(
1143         {getOpenMPContextTraitPropertyForSelector(TISelector.Kind)});
1144     return;
1145   }
1146 
1147   if (!Tok.is(tok::l_paren)) {
1148     Diag(SelectorLoc, diag::warn_omp_ctx_selector_without_properties)
1149         << getOpenMPContextTraitSelectorName(TISelector.Kind)
1150         << getOpenMPContextTraitSetName(Set);
1151     return FinishSelector();
1152   }
1153 
1154   if (TISelector.Kind == TraitSelector::user_condition) {
1155     SourceLocation RLoc;
1156     ExprResult Condition = ParseOpenMPParensExpr("user condition", RLoc);
1157     if (!Condition.isUsable())
1158       return FinishSelector();
1159     TISelector.ScoreOrCondition = Condition.get();
1160     TISelector.Properties.push_back({TraitProperty::user_condition_unknown});
1161     return;
1162   }
1163 
1164   BalancedDelimiterTracker BDT(*this, tok::l_paren,
1165                                tok::annot_pragma_openmp_end);
1166   // Parse '('.
1167   (void)BDT.consumeOpen();
1168 
1169   SourceLocation ScoreLoc = Tok.getLocation();
1170   ExprResult Score = parseContextScore(*this);
1171 
1172   if (!AllowsTraitScore && !Score.isUnset()) {
1173     if (Score.isUsable()) {
1174       Diag(ScoreLoc, diag::warn_omp_ctx_incompatible_score_for_property)
1175           << getOpenMPContextTraitSelectorName(TISelector.Kind)
1176           << getOpenMPContextTraitSetName(Set) << Score.get();
1177     } else {
1178       Diag(ScoreLoc, diag::warn_omp_ctx_incompatible_score_for_property)
1179           << getOpenMPContextTraitSelectorName(TISelector.Kind)
1180           << getOpenMPContextTraitSetName(Set) << "<invalid>";
1181     }
1182     Score = ExprResult();
1183   }
1184 
1185   if (Score.isUsable())
1186     TISelector.ScoreOrCondition = Score.get();
1187 
1188   llvm::StringMap<SourceLocation> SeenProperties;
1189   do {
1190     parseOMPContextProperty(TISelector, Set, SeenProperties);
1191   } while (TryConsumeToken(tok::comma));
1192 
1193   // Parse ')'.
1194   BDT.consumeClose();
1195 }
1196 
1197 void Parser::parseOMPTraitSetKind(OMPTraitSet &TISet,
1198                                   llvm::StringMap<SourceLocation> &Seen) {
1199   TISet.Kind = TraitSet::invalid;
1200 
1201   SourceLocation NameLoc = Tok.getLocation();
1202   StringRef Name = getNameFromIdOrString(*this, Tok, CONTEXT_SELECTOR_SET_LVL
1203                    );
1204   if (Name.empty()) {
1205     Diag(Tok.getLocation(), diag::note_omp_declare_variant_ctx_options)
1206         << CONTEXT_SELECTOR_SET_LVL << listOpenMPContextTraitSets();
1207     return;
1208   }
1209 
1210   TISet.Kind = getOpenMPContextTraitSetKind(Name);
1211   if (TISet.Kind != TraitSet::invalid) {
1212     if (checkForDuplicates(*this, Name, NameLoc, Seen,
1213                            CONTEXT_SELECTOR_SET_LVL))
1214       TISet.Kind = TraitSet::invalid;
1215     return;
1216   }
1217 
1218   // It follows diagnosis and helping notes.
1219   Diag(NameLoc, diag::warn_omp_declare_variant_ctx_not_a_set) << Name;
1220 
1221   TraitSelector SelectorForName = getOpenMPContextTraitSelectorKind(Name);
1222   if (SelectorForName != TraitSelector::invalid) {
1223     Diag(NameLoc, diag::note_omp_declare_variant_ctx_is_a)
1224         << Name << CONTEXT_SELECTOR_LVL << CONTEXT_SELECTOR_SET_LVL;
1225     bool AllowsTraitScore = false;
1226     bool RequiresProperty = false;
1227     isValidTraitSelectorForTraitSet(
1228         SelectorForName, getOpenMPContextTraitSetForSelector(SelectorForName),
1229         AllowsTraitScore, RequiresProperty);
1230     Diag(NameLoc, diag::note_omp_declare_variant_ctx_try)
1231         << getOpenMPContextTraitSetName(
1232                getOpenMPContextTraitSetForSelector(SelectorForName))
1233         << Name << (RequiresProperty ? "(<property-name>)" : "");
1234     return;
1235   }
1236   for (const auto &PotentialSet :
1237        {TraitSet::construct, TraitSet::user, TraitSet::implementation,
1238         TraitSet::device}) {
1239     TraitProperty PropertyForName =
1240         getOpenMPContextTraitPropertyKind(PotentialSet, Name);
1241     if (PropertyForName == TraitProperty::invalid)
1242       continue;
1243     Diag(NameLoc, diag::note_omp_declare_variant_ctx_is_a)
1244         << Name << CONTEXT_TRAIT_LVL << CONTEXT_SELECTOR_SET_LVL;
1245     Diag(NameLoc, diag::note_omp_declare_variant_ctx_try)
1246         << getOpenMPContextTraitSetName(
1247                getOpenMPContextTraitSetForProperty(PropertyForName))
1248         << getOpenMPContextTraitSelectorName(
1249                getOpenMPContextTraitSelectorForProperty(PropertyForName))
1250         << ("(" + Name + ")").str();
1251     return;
1252   }
1253   Diag(NameLoc, diag::note_omp_declare_variant_ctx_options)
1254       << CONTEXT_SELECTOR_SET_LVL << listOpenMPContextTraitSets();
1255 }
1256 
1257 /// Parses an OpenMP context selector set.
1258 ///
1259 /// <trait-set-selector-name> '=' '{' <trait-selector> [, <trait-selector>]* '}'
1260 void Parser::parseOMPContextSelectorSet(
1261     OMPTraitSet &TISet,
1262     llvm::StringMap<SourceLocation> &SeenSets) {
1263   auto OuterBC = BraceCount;
1264 
1265   // If anything went wrong we issue an error or warning and then skip the rest
1266   // of the set. However, commas are ambiguous so we look for the nesting
1267   // of braces here as well.
1268   auto FinishSelectorSet = [this, OuterBC]() -> void {
1269     bool Done = false;
1270     while (!Done) {
1271       while (!SkipUntil({tok::comma, tok::r_brace, tok::r_paren,
1272                          tok::annot_pragma_openmp_end},
1273                         StopBeforeMatch))
1274         ;
1275       if (Tok.is(tok::r_brace) && OuterBC > BraceCount)
1276         (void)ConsumeBrace();
1277       if (OuterBC <= BraceCount) {
1278         Done = true;
1279         break;
1280       }
1281       if (!Tok.is(tok::comma) && !Tok.is(tok::r_brace)) {
1282         Done = true;
1283         break;
1284       }
1285       (void)ConsumeAnyToken();
1286     }
1287     Diag(Tok.getLocation(), diag::note_omp_declare_variant_ctx_continue_here)
1288         << CONTEXT_SELECTOR_SET_LVL;
1289   };
1290 
1291   parseOMPTraitSetKind(TISet, SeenSets);
1292   if (TISet.Kind == TraitSet::invalid)
1293     return FinishSelectorSet();
1294 
1295   // Parse '='.
1296   if (!TryConsumeToken(tok::equal))
1297     Diag(Tok.getLocation(), diag::warn_omp_declare_variant_expected)
1298         << "="
1299         << ("context set name \"" + getOpenMPContextTraitSetName(TISet.Kind) +
1300             "\"")
1301                .str();
1302 
1303   // Parse '{'.
1304   if (Tok.is(tok::l_brace)) {
1305     (void)ConsumeBrace();
1306   } else {
1307     Diag(Tok.getLocation(), diag::warn_omp_declare_variant_expected)
1308         << "{"
1309         << ("'=' that follows the context set name \"" +
1310             getOpenMPContextTraitSetName(TISet.Kind) + "\"")
1311                .str();
1312   }
1313 
1314   llvm::StringMap<SourceLocation> SeenSelectors;
1315   do {
1316     OMPTraitSelector TISelector;
1317     parseOMPContextSelector(TISelector, TISet.Kind, SeenSelectors);
1318     if (TISelector.Kind != TraitSelector::invalid &&
1319         !TISelector.Properties.empty())
1320       TISet.Selectors.push_back(TISelector);
1321   } while (TryConsumeToken(tok::comma));
1322 
1323   // Parse '}'.
1324   if (Tok.is(tok::r_brace)) {
1325     (void)ConsumeBrace();
1326   } else {
1327     Diag(Tok.getLocation(), diag::warn_omp_declare_variant_expected)
1328         << "}"
1329         << ("context selectors for the context set \"" +
1330             getOpenMPContextTraitSetName(TISet.Kind) + "\"")
1331                .str();
1332   }
1333 }
1334 
1335 /// Parse OpenMP context selectors:
1336 ///
1337 /// <trait-set-selector> [, <trait-set-selector>]*
1338 bool Parser::parseOMPContextSelectors(SourceLocation Loc, OMPTraitInfo& TI) {
1339   llvm::StringMap<SourceLocation> SeenSets;
1340   do {
1341     OMPTraitSet TISet;
1342     parseOMPContextSelectorSet(TISet, SeenSets);
1343     if (TISet.Kind != TraitSet::invalid && !TISet.Selectors.empty())
1344       TI.Sets.push_back(TISet);
1345   } while (TryConsumeToken(tok::comma));
1346 
1347   return false;
1348 }
1349 
1350 /// Parse clauses for '#pragma omp declare variant ( variant-func-id ) clause'.
1351 void Parser::ParseOMPDeclareVariantClauses(Parser::DeclGroupPtrTy Ptr,
1352                                            CachedTokens &Toks,
1353                                            SourceLocation Loc) {
1354   PP.EnterToken(Tok, /*IsReinject*/ true);
1355   PP.EnterTokenStream(Toks, /*DisableMacroExpansion=*/true,
1356                       /*IsReinject*/ true);
1357   // Consume the previously pushed token.
1358   ConsumeAnyToken(/*ConsumeCodeCompletionTok=*/true);
1359   ConsumeAnyToken(/*ConsumeCodeCompletionTok=*/true);
1360 
1361   FNContextRAII FnContext(*this, Ptr);
1362   // Parse function declaration id.
1363   SourceLocation RLoc;
1364   // Parse with IsAddressOfOperand set to true to parse methods as DeclRefExprs
1365   // instead of MemberExprs.
1366   ExprResult AssociatedFunction;
1367   {
1368     // Do not mark function as is used to prevent its emission if this is the
1369     // only place where it is used.
1370     EnterExpressionEvaluationContext Unevaluated(
1371         Actions, Sema::ExpressionEvaluationContext::Unevaluated);
1372     AssociatedFunction = ParseOpenMPParensExpr(
1373         getOpenMPDirectiveName(OMPD_declare_variant), RLoc,
1374         /*IsAddressOfOperand=*/true);
1375   }
1376   if (!AssociatedFunction.isUsable()) {
1377     if (!Tok.is(tok::annot_pragma_openmp_end))
1378       while (!SkipUntil(tok::annot_pragma_openmp_end, StopBeforeMatch))
1379         ;
1380     // Skip the last annot_pragma_openmp_end.
1381     (void)ConsumeAnnotationToken();
1382     return;
1383   }
1384 
1385   OMPTraitInfo &TI = Actions.getASTContext().getNewOMPTraitInfo();
1386   if (parseOMPDeclareVariantMatchClause(Loc, TI))
1387     return;
1388 
1389   Optional<std::pair<FunctionDecl *, Expr *>> DeclVarData =
1390       Actions.checkOpenMPDeclareVariantFunction(
1391           Ptr, AssociatedFunction.get(), TI,
1392           SourceRange(Loc, Tok.getLocation()));
1393 
1394   // Skip last tokens.
1395   while (Tok.isNot(tok::annot_pragma_openmp_end))
1396     ConsumeAnyToken();
1397   if (DeclVarData && !TI.Sets.empty())
1398     Actions.ActOnOpenMPDeclareVariantDirective(
1399         DeclVarData->first, DeclVarData->second, TI,
1400         SourceRange(Loc, Tok.getLocation()));
1401 
1402   // Skip the last annot_pragma_openmp_end.
1403   (void)ConsumeAnnotationToken();
1404 }
1405 
1406 bool Parser::parseOMPDeclareVariantMatchClause(SourceLocation Loc,
1407                                                OMPTraitInfo &TI) {
1408   // Parse 'match'.
1409   OpenMPClauseKind CKind = Tok.isAnnotation()
1410                                ? OMPC_unknown
1411                                : getOpenMPClauseKind(PP.getSpelling(Tok));
1412   if (CKind != OMPC_match) {
1413     Diag(Tok.getLocation(), diag::err_omp_declare_variant_wrong_clause)
1414         << getOpenMPClauseName(OMPC_match);
1415     while (!SkipUntil(tok::annot_pragma_openmp_end, Parser::StopBeforeMatch))
1416       ;
1417     // Skip the last annot_pragma_openmp_end.
1418     (void)ConsumeAnnotationToken();
1419     return true;
1420   }
1421   (void)ConsumeToken();
1422   // Parse '('.
1423   BalancedDelimiterTracker T(*this, tok::l_paren, tok::annot_pragma_openmp_end);
1424   if (T.expectAndConsume(diag::err_expected_lparen_after,
1425                          getOpenMPClauseName(OMPC_match).data())) {
1426     while (!SkipUntil(tok::annot_pragma_openmp_end, StopBeforeMatch))
1427       ;
1428     // Skip the last annot_pragma_openmp_end.
1429     (void)ConsumeAnnotationToken();
1430     return true;
1431   }
1432 
1433   // Parse inner context selectors.
1434   parseOMPContextSelectors(Loc, TI);
1435 
1436   // Parse ')'
1437   (void)T.consumeClose();
1438   return false;
1439 }
1440 
1441 /// Parsing of simple OpenMP clauses like 'default' or 'proc_bind'.
1442 ///
1443 ///    default-clause:
1444 ///         'default' '(' 'none' | 'shared'  | 'firstprivate' ')
1445 ///
1446 ///    proc_bind-clause:
1447 ///         'proc_bind' '(' 'master' | 'close' | 'spread' ')
1448 ///
1449 ///    device_type-clause:
1450 ///         'device_type' '(' 'host' | 'nohost' | 'any' )'
1451 namespace {
1452   struct SimpleClauseData {
1453     unsigned Type;
1454     SourceLocation Loc;
1455     SourceLocation LOpen;
1456     SourceLocation TypeLoc;
1457     SourceLocation RLoc;
1458     SimpleClauseData(unsigned Type, SourceLocation Loc, SourceLocation LOpen,
1459                      SourceLocation TypeLoc, SourceLocation RLoc)
1460         : Type(Type), Loc(Loc), LOpen(LOpen), TypeLoc(TypeLoc), RLoc(RLoc) {}
1461   };
1462 } // anonymous namespace
1463 
1464 static Optional<SimpleClauseData>
1465 parseOpenMPSimpleClause(Parser &P, OpenMPClauseKind Kind) {
1466   const Token &Tok = P.getCurToken();
1467   SourceLocation Loc = Tok.getLocation();
1468   SourceLocation LOpen = P.ConsumeToken();
1469   // Parse '('.
1470   BalancedDelimiterTracker T(P, tok::l_paren, tok::annot_pragma_openmp_end);
1471   if (T.expectAndConsume(diag::err_expected_lparen_after,
1472                          getOpenMPClauseName(Kind).data()))
1473     return llvm::None;
1474 
1475   unsigned Type = getOpenMPSimpleClauseType(
1476       Kind, Tok.isAnnotation() ? "" : P.getPreprocessor().getSpelling(Tok));
1477   SourceLocation TypeLoc = Tok.getLocation();
1478   if (Tok.isNot(tok::r_paren) && Tok.isNot(tok::comma) &&
1479       Tok.isNot(tok::annot_pragma_openmp_end))
1480     P.ConsumeAnyToken();
1481 
1482   // Parse ')'.
1483   SourceLocation RLoc = Tok.getLocation();
1484   if (!T.consumeClose())
1485     RLoc = T.getCloseLocation();
1486 
1487   return SimpleClauseData(Type, Loc, LOpen, TypeLoc, RLoc);
1488 }
1489 
1490 Parser::DeclGroupPtrTy Parser::ParseOMPDeclareTargetClauses() {
1491   // OpenMP 4.5 syntax with list of entities.
1492   Sema::NamedDeclSetType SameDirectiveDecls;
1493   SmallVector<std::tuple<OMPDeclareTargetDeclAttr::MapTypeTy, SourceLocation,
1494                          NamedDecl *>,
1495               4>
1496       DeclareTargetDecls;
1497   OMPDeclareTargetDeclAttr::DevTypeTy DT = OMPDeclareTargetDeclAttr::DT_Any;
1498   SourceLocation DeviceTypeLoc;
1499   while (Tok.isNot(tok::annot_pragma_openmp_end)) {
1500     OMPDeclareTargetDeclAttr::MapTypeTy MT = OMPDeclareTargetDeclAttr::MT_To;
1501     if (Tok.is(tok::identifier)) {
1502       IdentifierInfo *II = Tok.getIdentifierInfo();
1503       StringRef ClauseName = II->getName();
1504       bool IsDeviceTypeClause =
1505           getLangOpts().OpenMP >= 50 &&
1506           getOpenMPClauseKind(ClauseName) == OMPC_device_type;
1507       // Parse 'to|link|device_type' clauses.
1508       if (!OMPDeclareTargetDeclAttr::ConvertStrToMapTypeTy(ClauseName, MT) &&
1509           !IsDeviceTypeClause) {
1510         Diag(Tok, diag::err_omp_declare_target_unexpected_clause)
1511             << ClauseName << (getLangOpts().OpenMP >= 50 ? 1 : 0);
1512         break;
1513       }
1514       // Parse 'device_type' clause and go to next clause if any.
1515       if (IsDeviceTypeClause) {
1516         Optional<SimpleClauseData> DevTypeData =
1517             parseOpenMPSimpleClause(*this, OMPC_device_type);
1518         if (DevTypeData.hasValue()) {
1519           if (DeviceTypeLoc.isValid()) {
1520             // We already saw another device_type clause, diagnose it.
1521             Diag(DevTypeData.getValue().Loc,
1522                  diag::warn_omp_more_one_device_type_clause);
1523           }
1524           switch(static_cast<OpenMPDeviceType>(DevTypeData.getValue().Type)) {
1525           case OMPC_DEVICE_TYPE_any:
1526             DT = OMPDeclareTargetDeclAttr::DT_Any;
1527             break;
1528           case OMPC_DEVICE_TYPE_host:
1529             DT = OMPDeclareTargetDeclAttr::DT_Host;
1530             break;
1531           case OMPC_DEVICE_TYPE_nohost:
1532             DT = OMPDeclareTargetDeclAttr::DT_NoHost;
1533             break;
1534           case OMPC_DEVICE_TYPE_unknown:
1535             llvm_unreachable("Unexpected device_type");
1536           }
1537           DeviceTypeLoc = DevTypeData.getValue().Loc;
1538         }
1539         continue;
1540       }
1541       ConsumeToken();
1542     }
1543     auto &&Callback = [this, MT, &DeclareTargetDecls, &SameDirectiveDecls](
1544                           CXXScopeSpec &SS, DeclarationNameInfo NameInfo) {
1545       NamedDecl *ND = Actions.lookupOpenMPDeclareTargetName(
1546           getCurScope(), SS, NameInfo, SameDirectiveDecls);
1547       if (ND)
1548         DeclareTargetDecls.emplace_back(MT, NameInfo.getLoc(), ND);
1549     };
1550     if (ParseOpenMPSimpleVarList(OMPD_declare_target, Callback,
1551                                  /*AllowScopeSpecifier=*/true))
1552       break;
1553 
1554     // Consume optional ','.
1555     if (Tok.is(tok::comma))
1556       ConsumeToken();
1557   }
1558   SkipUntil(tok::annot_pragma_openmp_end, StopBeforeMatch);
1559   ConsumeAnyToken();
1560   for (auto &MTLocDecl : DeclareTargetDecls) {
1561     OMPDeclareTargetDeclAttr::MapTypeTy MT;
1562     SourceLocation Loc;
1563     NamedDecl *ND;
1564     std::tie(MT, Loc, ND) = MTLocDecl;
1565     // device_type clause is applied only to functions.
1566     Actions.ActOnOpenMPDeclareTargetName(
1567         ND, Loc, MT, isa<VarDecl>(ND) ? OMPDeclareTargetDeclAttr::DT_Any : DT);
1568   }
1569   SmallVector<Decl *, 4> Decls(SameDirectiveDecls.begin(),
1570                                SameDirectiveDecls.end());
1571   if (Decls.empty())
1572     return DeclGroupPtrTy();
1573   return Actions.BuildDeclaratorGroup(Decls);
1574 }
1575 
1576 void Parser::skipUntilPragmaOpenMPEnd(OpenMPDirectiveKind DKind) {
1577   // The last seen token is annot_pragma_openmp_end - need to check for
1578   // extra tokens.
1579   if (Tok.is(tok::annot_pragma_openmp_end))
1580     return;
1581 
1582   Diag(Tok, diag::warn_omp_extra_tokens_at_eol)
1583       << getOpenMPDirectiveName(DKind);
1584   while (Tok.isNot(tok::annot_pragma_openmp_end))
1585     ConsumeAnyToken();
1586 }
1587 
1588 void Parser::parseOMPEndDirective(OpenMPDirectiveKind BeginKind,
1589                                   OpenMPDirectiveKind ExpectedKind,
1590                                   OpenMPDirectiveKind FoundKind,
1591                                   SourceLocation BeginLoc,
1592                                   SourceLocation FoundLoc,
1593                                   bool SkipUntilOpenMPEnd) {
1594   int DiagSelection = ExpectedKind == OMPD_end_declare_target ? 0 : 1;
1595 
1596   if (FoundKind == ExpectedKind) {
1597     ConsumeAnyToken();
1598     skipUntilPragmaOpenMPEnd(ExpectedKind);
1599     return;
1600   }
1601 
1602   Diag(FoundLoc, diag::err_expected_end_declare_target_or_variant)
1603       << DiagSelection;
1604   Diag(BeginLoc, diag::note_matching)
1605       << ("'#pragma omp " + getOpenMPDirectiveName(BeginKind) + "'").str();
1606   if (SkipUntilOpenMPEnd)
1607     SkipUntil(tok::annot_pragma_openmp_end, StopBeforeMatch);
1608 }
1609 
1610 void Parser::ParseOMPEndDeclareTargetDirective(OpenMPDirectiveKind DKind,
1611                                                SourceLocation DKLoc) {
1612   parseOMPEndDirective(OMPD_declare_target, OMPD_end_declare_target, DKind,
1613                        DKLoc, Tok.getLocation(),
1614                        /* SkipUntilOpenMPEnd */ false);
1615   // Skip the last annot_pragma_openmp_end.
1616   if (Tok.is(tok::annot_pragma_openmp_end))
1617     ConsumeAnnotationToken();
1618 }
1619 
1620 /// Parsing of declarative OpenMP directives.
1621 ///
1622 ///       threadprivate-directive:
1623 ///         annot_pragma_openmp 'threadprivate' simple-variable-list
1624 ///         annot_pragma_openmp_end
1625 ///
1626 ///       allocate-directive:
1627 ///         annot_pragma_openmp 'allocate' simple-variable-list [<clause>]
1628 ///         annot_pragma_openmp_end
1629 ///
1630 ///       declare-reduction-directive:
1631 ///        annot_pragma_openmp 'declare' 'reduction' [...]
1632 ///        annot_pragma_openmp_end
1633 ///
1634 ///       declare-mapper-directive:
1635 ///         annot_pragma_openmp 'declare' 'mapper' '(' [<mapper-identifer> ':']
1636 ///         <type> <var> ')' [<clause>[[,] <clause>] ... ]
1637 ///         annot_pragma_openmp_end
1638 ///
1639 ///       declare-simd-directive:
1640 ///         annot_pragma_openmp 'declare simd' {<clause> [,]}
1641 ///         annot_pragma_openmp_end
1642 ///         <function declaration/definition>
1643 ///
1644 ///       requires directive:
1645 ///         annot_pragma_openmp 'requires' <clause> [[[,] <clause>] ... ]
1646 ///         annot_pragma_openmp_end
1647 ///
1648 Parser::DeclGroupPtrTy Parser::ParseOpenMPDeclarativeDirectiveWithExtDecl(
1649     AccessSpecifier &AS, ParsedAttributesWithRange &Attrs, bool Delayed,
1650     DeclSpec::TST TagType, Decl *Tag) {
1651   assert(Tok.is(tok::annot_pragma_openmp) && "Not an OpenMP directive!");
1652   ParsingOpenMPDirectiveRAII DirScope(*this);
1653   ParenBraceBracketBalancer BalancerRAIIObj(*this);
1654 
1655   SourceLocation Loc;
1656   OpenMPDirectiveKind DKind;
1657   if (Delayed) {
1658     TentativeParsingAction TPA(*this);
1659     Loc = ConsumeAnnotationToken();
1660     DKind = parseOpenMPDirectiveKind(*this);
1661     if (DKind == OMPD_declare_reduction || DKind == OMPD_declare_mapper) {
1662       // Need to delay parsing until completion of the parent class.
1663       TPA.Revert();
1664       CachedTokens Toks;
1665       unsigned Cnt = 1;
1666       Toks.push_back(Tok);
1667       while (Cnt && Tok.isNot(tok::eof)) {
1668         (void)ConsumeAnyToken();
1669         if (Tok.is(tok::annot_pragma_openmp))
1670           ++Cnt;
1671         else if (Tok.is(tok::annot_pragma_openmp_end))
1672           --Cnt;
1673         Toks.push_back(Tok);
1674       }
1675       // Skip last annot_pragma_openmp_end.
1676       if (Cnt == 0)
1677         (void)ConsumeAnyToken();
1678       auto *LP = new LateParsedPragma(this, AS);
1679       LP->takeToks(Toks);
1680       getCurrentClass().LateParsedDeclarations.push_back(LP);
1681       return nullptr;
1682     }
1683     TPA.Commit();
1684   } else {
1685     Loc = ConsumeAnnotationToken();
1686     DKind = parseOpenMPDirectiveKind(*this);
1687   }
1688 
1689   switch (DKind) {
1690   case OMPD_threadprivate: {
1691     ConsumeToken();
1692     DeclDirectiveListParserHelper Helper(this, DKind);
1693     if (!ParseOpenMPSimpleVarList(DKind, Helper,
1694                                   /*AllowScopeSpecifier=*/true)) {
1695       skipUntilPragmaOpenMPEnd(DKind);
1696       // Skip the last annot_pragma_openmp_end.
1697       ConsumeAnnotationToken();
1698       return Actions.ActOnOpenMPThreadprivateDirective(Loc,
1699                                                        Helper.getIdentifiers());
1700     }
1701     break;
1702   }
1703   case OMPD_allocate: {
1704     ConsumeToken();
1705     DeclDirectiveListParserHelper Helper(this, DKind);
1706     if (!ParseOpenMPSimpleVarList(DKind, Helper,
1707                                   /*AllowScopeSpecifier=*/true)) {
1708       SmallVector<OMPClause *, 1> Clauses;
1709       if (Tok.isNot(tok::annot_pragma_openmp_end)) {
1710         SmallVector<llvm::PointerIntPair<OMPClause *, 1, bool>,
1711                     llvm::omp::Clause_enumSize + 1>
1712             FirstClauses(llvm::omp::Clause_enumSize + 1);
1713         while (Tok.isNot(tok::annot_pragma_openmp_end)) {
1714           OpenMPClauseKind CKind =
1715               Tok.isAnnotation() ? OMPC_unknown
1716                                  : getOpenMPClauseKind(PP.getSpelling(Tok));
1717           Actions.StartOpenMPClause(CKind);
1718           OMPClause *Clause = ParseOpenMPClause(
1719               OMPD_allocate, CKind, !FirstClauses[unsigned(CKind)].getInt());
1720           SkipUntil(tok::comma, tok::identifier, tok::annot_pragma_openmp_end,
1721                     StopBeforeMatch);
1722           FirstClauses[unsigned(CKind)].setInt(true);
1723           if (Clause != nullptr)
1724             Clauses.push_back(Clause);
1725           if (Tok.is(tok::annot_pragma_openmp_end)) {
1726             Actions.EndOpenMPClause();
1727             break;
1728           }
1729           // Skip ',' if any.
1730           if (Tok.is(tok::comma))
1731             ConsumeToken();
1732           Actions.EndOpenMPClause();
1733         }
1734         skipUntilPragmaOpenMPEnd(DKind);
1735       }
1736       // Skip the last annot_pragma_openmp_end.
1737       ConsumeAnnotationToken();
1738       return Actions.ActOnOpenMPAllocateDirective(Loc, Helper.getIdentifiers(),
1739                                                   Clauses);
1740     }
1741     break;
1742   }
1743   case OMPD_requires: {
1744     SourceLocation StartLoc = ConsumeToken();
1745     SmallVector<OMPClause *, 5> Clauses;
1746     SmallVector<llvm::PointerIntPair<OMPClause *, 1, bool>,
1747                 llvm::omp::Clause_enumSize + 1>
1748         FirstClauses(llvm::omp::Clause_enumSize + 1);
1749     if (Tok.is(tok::annot_pragma_openmp_end)) {
1750       Diag(Tok, diag::err_omp_expected_clause)
1751           << getOpenMPDirectiveName(OMPD_requires);
1752       break;
1753     }
1754     while (Tok.isNot(tok::annot_pragma_openmp_end)) {
1755       OpenMPClauseKind CKind = Tok.isAnnotation()
1756                                    ? OMPC_unknown
1757                                    : getOpenMPClauseKind(PP.getSpelling(Tok));
1758       Actions.StartOpenMPClause(CKind);
1759       OMPClause *Clause = ParseOpenMPClause(
1760           OMPD_requires, CKind, !FirstClauses[unsigned(CKind)].getInt());
1761       SkipUntil(tok::comma, tok::identifier, tok::annot_pragma_openmp_end,
1762                 StopBeforeMatch);
1763       FirstClauses[unsigned(CKind)].setInt(true);
1764       if (Clause != nullptr)
1765         Clauses.push_back(Clause);
1766       if (Tok.is(tok::annot_pragma_openmp_end)) {
1767         Actions.EndOpenMPClause();
1768         break;
1769       }
1770       // Skip ',' if any.
1771       if (Tok.is(tok::comma))
1772         ConsumeToken();
1773       Actions.EndOpenMPClause();
1774     }
1775     // Consume final annot_pragma_openmp_end
1776     if (Clauses.empty()) {
1777       Diag(Tok, diag::err_omp_expected_clause)
1778           << getOpenMPDirectiveName(OMPD_requires);
1779       ConsumeAnnotationToken();
1780       return nullptr;
1781     }
1782     ConsumeAnnotationToken();
1783     return Actions.ActOnOpenMPRequiresDirective(StartLoc, Clauses);
1784   }
1785   case OMPD_declare_reduction:
1786     ConsumeToken();
1787     if (DeclGroupPtrTy Res = ParseOpenMPDeclareReductionDirective(AS)) {
1788       skipUntilPragmaOpenMPEnd(OMPD_declare_reduction);
1789       // Skip the last annot_pragma_openmp_end.
1790       ConsumeAnnotationToken();
1791       return Res;
1792     }
1793     break;
1794   case OMPD_declare_mapper: {
1795     ConsumeToken();
1796     if (DeclGroupPtrTy Res = ParseOpenMPDeclareMapperDirective(AS)) {
1797       // Skip the last annot_pragma_openmp_end.
1798       ConsumeAnnotationToken();
1799       return Res;
1800     }
1801     break;
1802   }
1803   case OMPD_begin_declare_variant: {
1804     // The syntax is:
1805     // { #pragma omp begin declare variant clause }
1806     // <function-declaration-or-definition-sequence>
1807     // { #pragma omp end declare variant }
1808     //
1809     ConsumeToken();
1810     OMPTraitInfo &TI = Actions.getASTContext().getNewOMPTraitInfo();
1811     if (parseOMPDeclareVariantMatchClause(Loc, TI))
1812       break;
1813 
1814     // Skip last tokens.
1815     skipUntilPragmaOpenMPEnd(OMPD_begin_declare_variant);
1816 
1817     ParsingOpenMPDirectiveRAII NormalScope(*this, /*Value=*/false);
1818 
1819     VariantMatchInfo VMI;
1820     ASTContext &ASTCtx = Actions.getASTContext();
1821     TI.getAsVariantMatchInfo(ASTCtx, VMI);
1822     OMPContext OMPCtx(ASTCtx.getLangOpts().OpenMPIsDevice,
1823                       ASTCtx.getTargetInfo().getTriple());
1824 
1825     if (isVariantApplicableInContext(VMI, OMPCtx, /* DeviceSetOnly */ true)) {
1826       Actions.ActOnOpenMPBeginDeclareVariant(Loc, TI);
1827       break;
1828     }
1829 
1830     // Elide all the code till the matching end declare variant was found.
1831     unsigned Nesting = 1;
1832     SourceLocation DKLoc;
1833     OpenMPDirectiveKind DK = OMPD_unknown;
1834     do {
1835       DKLoc = Tok.getLocation();
1836       DK = parseOpenMPDirectiveKind(*this);
1837       if (DK == OMPD_end_declare_variant)
1838         --Nesting;
1839       else if (DK == OMPD_begin_declare_variant)
1840         ++Nesting;
1841       if (!Nesting || isEofOrEom())
1842         break;
1843       ConsumeAnyToken();
1844     } while (true);
1845 
1846     parseOMPEndDirective(OMPD_begin_declare_variant, OMPD_end_declare_variant,
1847                          DK, Loc, DKLoc, /* SkipUntilOpenMPEnd */ true);
1848     if (isEofOrEom())
1849       return nullptr;
1850     break;
1851   }
1852   case OMPD_end_declare_variant: {
1853     if (Actions.isInOpenMPDeclareVariantScope())
1854       Actions.ActOnOpenMPEndDeclareVariant();
1855     else
1856       Diag(Loc, diag::err_expected_begin_declare_variant);
1857     ConsumeToken();
1858     break;
1859   }
1860   case OMPD_declare_variant:
1861   case OMPD_declare_simd: {
1862     // The syntax is:
1863     // { #pragma omp declare {simd|variant} }
1864     // <function-declaration-or-definition>
1865     //
1866     CachedTokens Toks;
1867     Toks.push_back(Tok);
1868     ConsumeToken();
1869     while(Tok.isNot(tok::annot_pragma_openmp_end)) {
1870       Toks.push_back(Tok);
1871       ConsumeAnyToken();
1872     }
1873     Toks.push_back(Tok);
1874     ConsumeAnyToken();
1875 
1876     DeclGroupPtrTy Ptr;
1877     if (Tok.is(tok::annot_pragma_openmp)) {
1878       Ptr = ParseOpenMPDeclarativeDirectiveWithExtDecl(AS, Attrs, Delayed,
1879                                                        TagType, Tag);
1880     } else if (Tok.isNot(tok::r_brace) && !isEofOrEom()) {
1881       // Here we expect to see some function declaration.
1882       if (AS == AS_none) {
1883         assert(TagType == DeclSpec::TST_unspecified);
1884         MaybeParseCXX11Attributes(Attrs);
1885         ParsingDeclSpec PDS(*this);
1886         Ptr = ParseExternalDeclaration(Attrs, &PDS);
1887       } else {
1888         Ptr =
1889             ParseCXXClassMemberDeclarationWithPragmas(AS, Attrs, TagType, Tag);
1890       }
1891     }
1892     if (!Ptr) {
1893       Diag(Loc, diag::err_omp_decl_in_declare_simd_variant)
1894           << (DKind == OMPD_declare_simd ? 0 : 1);
1895       return DeclGroupPtrTy();
1896     }
1897     if (DKind == OMPD_declare_simd)
1898       return ParseOMPDeclareSimdClauses(Ptr, Toks, Loc);
1899     assert(DKind == OMPD_declare_variant &&
1900            "Expected declare variant directive only");
1901     ParseOMPDeclareVariantClauses(Ptr, Toks, Loc);
1902     return Ptr;
1903   }
1904   case OMPD_declare_target: {
1905     SourceLocation DTLoc = ConsumeAnyToken();
1906     if (Tok.isNot(tok::annot_pragma_openmp_end)) {
1907       return ParseOMPDeclareTargetClauses();
1908     }
1909 
1910     // Skip the last annot_pragma_openmp_end.
1911     ConsumeAnyToken();
1912 
1913     if (!Actions.ActOnStartOpenMPDeclareTargetDirective(DTLoc))
1914       return DeclGroupPtrTy();
1915 
1916     ParsingOpenMPDirectiveRAII NormalScope(*this, /*Value=*/false);
1917     llvm::SmallVector<Decl *, 4>  Decls;
1918     DKind = parseOpenMPDirectiveKind(*this);
1919     while (DKind != OMPD_end_declare_target && Tok.isNot(tok::eof) &&
1920            Tok.isNot(tok::r_brace)) {
1921       DeclGroupPtrTy Ptr;
1922       // Here we expect to see some function declaration.
1923       if (AS == AS_none) {
1924         assert(TagType == DeclSpec::TST_unspecified);
1925         MaybeParseCXX11Attributes(Attrs);
1926         ParsingDeclSpec PDS(*this);
1927         Ptr = ParseExternalDeclaration(Attrs, &PDS);
1928       } else {
1929         Ptr =
1930             ParseCXXClassMemberDeclarationWithPragmas(AS, Attrs, TagType, Tag);
1931       }
1932       if (Ptr) {
1933         DeclGroupRef Ref = Ptr.get();
1934         Decls.append(Ref.begin(), Ref.end());
1935       }
1936       if (Tok.isAnnotation() && Tok.is(tok::annot_pragma_openmp)) {
1937         TentativeParsingAction TPA(*this);
1938         ConsumeAnnotationToken();
1939         DKind = parseOpenMPDirectiveKind(*this);
1940         if (DKind != OMPD_end_declare_target)
1941           TPA.Revert();
1942         else
1943           TPA.Commit();
1944       }
1945     }
1946 
1947     ParseOMPEndDeclareTargetDirective(DKind, DTLoc);
1948     Actions.ActOnFinishOpenMPDeclareTargetDirective();
1949     return Actions.BuildDeclaratorGroup(Decls);
1950   }
1951   case OMPD_unknown:
1952     Diag(Tok, diag::err_omp_unknown_directive);
1953     break;
1954   case OMPD_parallel:
1955   case OMPD_simd:
1956   case OMPD_task:
1957   case OMPD_taskyield:
1958   case OMPD_barrier:
1959   case OMPD_taskwait:
1960   case OMPD_taskgroup:
1961   case OMPD_flush:
1962   case OMPD_depobj:
1963   case OMPD_scan:
1964   case OMPD_for:
1965   case OMPD_for_simd:
1966   case OMPD_sections:
1967   case OMPD_section:
1968   case OMPD_single:
1969   case OMPD_master:
1970   case OMPD_ordered:
1971   case OMPD_critical:
1972   case OMPD_parallel_for:
1973   case OMPD_parallel_for_simd:
1974   case OMPD_parallel_sections:
1975   case OMPD_parallel_master:
1976   case OMPD_atomic:
1977   case OMPD_target:
1978   case OMPD_teams:
1979   case OMPD_cancellation_point:
1980   case OMPD_cancel:
1981   case OMPD_target_data:
1982   case OMPD_target_enter_data:
1983   case OMPD_target_exit_data:
1984   case OMPD_target_parallel:
1985   case OMPD_target_parallel_for:
1986   case OMPD_taskloop:
1987   case OMPD_taskloop_simd:
1988   case OMPD_master_taskloop:
1989   case OMPD_master_taskloop_simd:
1990   case OMPD_parallel_master_taskloop:
1991   case OMPD_parallel_master_taskloop_simd:
1992   case OMPD_distribute:
1993   case OMPD_end_declare_target:
1994   case OMPD_target_update:
1995   case OMPD_distribute_parallel_for:
1996   case OMPD_distribute_parallel_for_simd:
1997   case OMPD_distribute_simd:
1998   case OMPD_target_parallel_for_simd:
1999   case OMPD_target_simd:
2000   case OMPD_teams_distribute:
2001   case OMPD_teams_distribute_simd:
2002   case OMPD_teams_distribute_parallel_for_simd:
2003   case OMPD_teams_distribute_parallel_for:
2004   case OMPD_target_teams:
2005   case OMPD_target_teams_distribute:
2006   case OMPD_target_teams_distribute_parallel_for:
2007   case OMPD_target_teams_distribute_parallel_for_simd:
2008   case OMPD_target_teams_distribute_simd:
2009     Diag(Tok, diag::err_omp_unexpected_directive)
2010         << 1 << getOpenMPDirectiveName(DKind);
2011     break;
2012   default:
2013     break;
2014   }
2015   while (Tok.isNot(tok::annot_pragma_openmp_end))
2016     ConsumeAnyToken();
2017   ConsumeAnyToken();
2018   return nullptr;
2019 }
2020 
2021 /// Parsing of declarative or executable OpenMP directives.
2022 ///
2023 ///       threadprivate-directive:
2024 ///         annot_pragma_openmp 'threadprivate' simple-variable-list
2025 ///         annot_pragma_openmp_end
2026 ///
2027 ///       allocate-directive:
2028 ///         annot_pragma_openmp 'allocate' simple-variable-list
2029 ///         annot_pragma_openmp_end
2030 ///
2031 ///       declare-reduction-directive:
2032 ///         annot_pragma_openmp 'declare' 'reduction' '(' <reduction_id> ':'
2033 ///         <type> {',' <type>} ':' <expression> ')' ['initializer' '('
2034 ///         ('omp_priv' '=' <expression>|<function_call>) ')']
2035 ///         annot_pragma_openmp_end
2036 ///
2037 ///       declare-mapper-directive:
2038 ///         annot_pragma_openmp 'declare' 'mapper' '(' [<mapper-identifer> ':']
2039 ///         <type> <var> ')' [<clause>[[,] <clause>] ... ]
2040 ///         annot_pragma_openmp_end
2041 ///
2042 ///       executable-directive:
2043 ///         annot_pragma_openmp 'parallel' | 'simd' | 'for' | 'sections' |
2044 ///         'section' | 'single' | 'master' | 'critical' [ '(' <name> ')' ] |
2045 ///         'parallel for' | 'parallel sections' | 'parallel master' | 'task' |
2046 ///         'taskyield' | 'barrier' | 'taskwait' | 'flush' | 'ordered' |
2047 ///         'atomic' | 'for simd' | 'parallel for simd' | 'target' | 'target
2048 ///         data' | 'taskgroup' | 'teams' | 'taskloop' | 'taskloop simd' |
2049 ///         'master taskloop' | 'master taskloop simd' | 'parallel master
2050 ///         taskloop' | 'parallel master taskloop simd' | 'distribute' | 'target
2051 ///         enter data' | 'target exit data' | 'target parallel' | 'target
2052 ///         parallel for' | 'target update' | 'distribute parallel for' |
2053 ///         'distribute paralle for simd' | 'distribute simd' | 'target parallel
2054 ///         for simd' | 'target simd' | 'teams distribute' | 'teams distribute
2055 ///         simd' | 'teams distribute parallel for simd' | 'teams distribute
2056 ///         parallel for' | 'target teams' | 'target teams distribute' | 'target
2057 ///         teams distribute parallel for' | 'target teams distribute parallel
2058 ///         for simd' | 'target teams distribute simd' {clause}
2059 ///         annot_pragma_openmp_end
2060 ///
2061 StmtResult
2062 Parser::ParseOpenMPDeclarativeOrExecutableDirective(ParsedStmtContext StmtCtx) {
2063   assert(Tok.is(tok::annot_pragma_openmp) && "Not an OpenMP directive!");
2064   ParsingOpenMPDirectiveRAII DirScope(*this);
2065   ParenBraceBracketBalancer BalancerRAIIObj(*this);
2066   SmallVector<OMPClause *, 5> Clauses;
2067   SmallVector<llvm::PointerIntPair<OMPClause *, 1, bool>,
2068               llvm::omp::Clause_enumSize + 1>
2069       FirstClauses(llvm::omp::Clause_enumSize + 1);
2070   unsigned ScopeFlags = Scope::FnScope | Scope::DeclScope |
2071                         Scope::CompoundStmtScope | Scope::OpenMPDirectiveScope;
2072   SourceLocation Loc = ConsumeAnnotationToken(), EndLoc;
2073   OpenMPDirectiveKind DKind = parseOpenMPDirectiveKind(*this);
2074   OpenMPDirectiveKind CancelRegion = OMPD_unknown;
2075   // Name of critical directive.
2076   DeclarationNameInfo DirName;
2077   StmtResult Directive = StmtError();
2078   bool HasAssociatedStatement = true;
2079 
2080   switch (DKind) {
2081   case OMPD_threadprivate: {
2082     // FIXME: Should this be permitted in C++?
2083     if ((StmtCtx & ParsedStmtContext::AllowDeclarationsInC) ==
2084         ParsedStmtContext()) {
2085       Diag(Tok, diag::err_omp_immediate_directive)
2086           << getOpenMPDirectiveName(DKind) << 0;
2087     }
2088     ConsumeToken();
2089     DeclDirectiveListParserHelper Helper(this, DKind);
2090     if (!ParseOpenMPSimpleVarList(DKind, Helper,
2091                                   /*AllowScopeSpecifier=*/false)) {
2092       skipUntilPragmaOpenMPEnd(DKind);
2093       DeclGroupPtrTy Res = Actions.ActOnOpenMPThreadprivateDirective(
2094           Loc, Helper.getIdentifiers());
2095       Directive = Actions.ActOnDeclStmt(Res, Loc, Tok.getLocation());
2096     }
2097     SkipUntil(tok::annot_pragma_openmp_end);
2098     break;
2099   }
2100   case OMPD_allocate: {
2101     // FIXME: Should this be permitted in C++?
2102     if ((StmtCtx & ParsedStmtContext::AllowDeclarationsInC) ==
2103         ParsedStmtContext()) {
2104       Diag(Tok, diag::err_omp_immediate_directive)
2105           << getOpenMPDirectiveName(DKind) << 0;
2106     }
2107     ConsumeToken();
2108     DeclDirectiveListParserHelper Helper(this, DKind);
2109     if (!ParseOpenMPSimpleVarList(DKind, Helper,
2110                                   /*AllowScopeSpecifier=*/false)) {
2111       SmallVector<OMPClause *, 1> Clauses;
2112       if (Tok.isNot(tok::annot_pragma_openmp_end)) {
2113         SmallVector<llvm::PointerIntPair<OMPClause *, 1, bool>,
2114                     llvm::omp::Clause_enumSize + 1>
2115             FirstClauses(llvm::omp::Clause_enumSize + 1);
2116         while (Tok.isNot(tok::annot_pragma_openmp_end)) {
2117           OpenMPClauseKind CKind =
2118               Tok.isAnnotation() ? OMPC_unknown
2119                                  : getOpenMPClauseKind(PP.getSpelling(Tok));
2120           Actions.StartOpenMPClause(CKind);
2121           OMPClause *Clause = ParseOpenMPClause(
2122               OMPD_allocate, CKind, !FirstClauses[unsigned(CKind)].getInt());
2123           SkipUntil(tok::comma, tok::identifier, tok::annot_pragma_openmp_end,
2124                     StopBeforeMatch);
2125           FirstClauses[unsigned(CKind)].setInt(true);
2126           if (Clause != nullptr)
2127             Clauses.push_back(Clause);
2128           if (Tok.is(tok::annot_pragma_openmp_end)) {
2129             Actions.EndOpenMPClause();
2130             break;
2131           }
2132           // Skip ',' if any.
2133           if (Tok.is(tok::comma))
2134             ConsumeToken();
2135           Actions.EndOpenMPClause();
2136         }
2137         skipUntilPragmaOpenMPEnd(DKind);
2138       }
2139       DeclGroupPtrTy Res = Actions.ActOnOpenMPAllocateDirective(
2140           Loc, Helper.getIdentifiers(), Clauses);
2141       Directive = Actions.ActOnDeclStmt(Res, Loc, Tok.getLocation());
2142     }
2143     SkipUntil(tok::annot_pragma_openmp_end);
2144     break;
2145   }
2146   case OMPD_declare_reduction:
2147     ConsumeToken();
2148     if (DeclGroupPtrTy Res =
2149             ParseOpenMPDeclareReductionDirective(/*AS=*/AS_none)) {
2150       skipUntilPragmaOpenMPEnd(OMPD_declare_reduction);
2151       ConsumeAnyToken();
2152       Directive = Actions.ActOnDeclStmt(Res, Loc, Tok.getLocation());
2153     } else {
2154       SkipUntil(tok::annot_pragma_openmp_end);
2155     }
2156     break;
2157   case OMPD_declare_mapper: {
2158     ConsumeToken();
2159     if (DeclGroupPtrTy Res =
2160             ParseOpenMPDeclareMapperDirective(/*AS=*/AS_none)) {
2161       // Skip the last annot_pragma_openmp_end.
2162       ConsumeAnnotationToken();
2163       Directive = Actions.ActOnDeclStmt(Res, Loc, Tok.getLocation());
2164     } else {
2165       SkipUntil(tok::annot_pragma_openmp_end);
2166     }
2167     break;
2168   }
2169   case OMPD_flush:
2170   case OMPD_depobj:
2171   case OMPD_scan:
2172   case OMPD_taskyield:
2173   case OMPD_barrier:
2174   case OMPD_taskwait:
2175   case OMPD_cancellation_point:
2176   case OMPD_cancel:
2177   case OMPD_target_enter_data:
2178   case OMPD_target_exit_data:
2179   case OMPD_target_update:
2180     if ((StmtCtx & ParsedStmtContext::AllowStandaloneOpenMPDirectives) ==
2181         ParsedStmtContext()) {
2182       Diag(Tok, diag::err_omp_immediate_directive)
2183           << getOpenMPDirectiveName(DKind) << 0;
2184     }
2185     HasAssociatedStatement = false;
2186     // Fall through for further analysis.
2187     LLVM_FALLTHROUGH;
2188   case OMPD_parallel:
2189   case OMPD_simd:
2190   case OMPD_for:
2191   case OMPD_for_simd:
2192   case OMPD_sections:
2193   case OMPD_single:
2194   case OMPD_section:
2195   case OMPD_master:
2196   case OMPD_critical:
2197   case OMPD_parallel_for:
2198   case OMPD_parallel_for_simd:
2199   case OMPD_parallel_sections:
2200   case OMPD_parallel_master:
2201   case OMPD_task:
2202   case OMPD_ordered:
2203   case OMPD_atomic:
2204   case OMPD_target:
2205   case OMPD_teams:
2206   case OMPD_taskgroup:
2207   case OMPD_target_data:
2208   case OMPD_target_parallel:
2209   case OMPD_target_parallel_for:
2210   case OMPD_taskloop:
2211   case OMPD_taskloop_simd:
2212   case OMPD_master_taskloop:
2213   case OMPD_master_taskloop_simd:
2214   case OMPD_parallel_master_taskloop:
2215   case OMPD_parallel_master_taskloop_simd:
2216   case OMPD_distribute:
2217   case OMPD_distribute_parallel_for:
2218   case OMPD_distribute_parallel_for_simd:
2219   case OMPD_distribute_simd:
2220   case OMPD_target_parallel_for_simd:
2221   case OMPD_target_simd:
2222   case OMPD_teams_distribute:
2223   case OMPD_teams_distribute_simd:
2224   case OMPD_teams_distribute_parallel_for_simd:
2225   case OMPD_teams_distribute_parallel_for:
2226   case OMPD_target_teams:
2227   case OMPD_target_teams_distribute:
2228   case OMPD_target_teams_distribute_parallel_for:
2229   case OMPD_target_teams_distribute_parallel_for_simd:
2230   case OMPD_target_teams_distribute_simd: {
2231     // Special processing for flush and depobj clauses.
2232     Token ImplicitTok;
2233     bool ImplicitClauseAllowed = false;
2234     if (DKind == OMPD_flush || DKind == OMPD_depobj) {
2235       ImplicitTok = Tok;
2236       ImplicitClauseAllowed = true;
2237     }
2238     ConsumeToken();
2239     // Parse directive name of the 'critical' directive if any.
2240     if (DKind == OMPD_critical) {
2241       BalancedDelimiterTracker T(*this, tok::l_paren,
2242                                  tok::annot_pragma_openmp_end);
2243       if (!T.consumeOpen()) {
2244         if (Tok.isAnyIdentifier()) {
2245           DirName =
2246               DeclarationNameInfo(Tok.getIdentifierInfo(), Tok.getLocation());
2247           ConsumeAnyToken();
2248         } else {
2249           Diag(Tok, diag::err_omp_expected_identifier_for_critical);
2250         }
2251         T.consumeClose();
2252       }
2253     } else if (DKind == OMPD_cancellation_point || DKind == OMPD_cancel) {
2254       CancelRegion = parseOpenMPDirectiveKind(*this);
2255       if (Tok.isNot(tok::annot_pragma_openmp_end))
2256         ConsumeToken();
2257     }
2258 
2259     if (isOpenMPLoopDirective(DKind))
2260       ScopeFlags |= Scope::OpenMPLoopDirectiveScope;
2261     if (isOpenMPSimdDirective(DKind))
2262       ScopeFlags |= Scope::OpenMPSimdDirectiveScope;
2263     ParseScope OMPDirectiveScope(this, ScopeFlags);
2264     Actions.StartOpenMPDSABlock(DKind, DirName, Actions.getCurScope(), Loc);
2265 
2266     while (Tok.isNot(tok::annot_pragma_openmp_end)) {
2267       bool HasImplicitClause = false;
2268       if (ImplicitClauseAllowed && Tok.is(tok::l_paren)) {
2269         HasImplicitClause = true;
2270         // Push copy of the current token back to stream to properly parse
2271         // pseudo-clause OMPFlushClause or OMPDepobjClause.
2272         PP.EnterToken(Tok, /*IsReinject*/ true);
2273         PP.EnterToken(ImplicitTok, /*IsReinject*/ true);
2274         ConsumeAnyToken();
2275       }
2276       OpenMPClauseKind CKind = Tok.isAnnotation()
2277                                    ? OMPC_unknown
2278                                    : getOpenMPClauseKind(PP.getSpelling(Tok));
2279       if (HasImplicitClause) {
2280         assert(CKind == OMPC_unknown && "Must be unknown implicit clause.");
2281         if (DKind == OMPD_flush) {
2282           CKind = OMPC_flush;
2283         } else {
2284           assert(DKind == OMPD_depobj &&
2285                  "Expected flush or depobj directives.");
2286           CKind = OMPC_depobj;
2287         }
2288       }
2289       // No more implicit clauses allowed.
2290       ImplicitClauseAllowed = false;
2291       Actions.StartOpenMPClause(CKind);
2292       HasImplicitClause = false;
2293       OMPClause *Clause = ParseOpenMPClause(
2294           DKind, CKind, !FirstClauses[unsigned(CKind)].getInt());
2295       FirstClauses[unsigned(CKind)].setInt(true);
2296       if (Clause) {
2297         FirstClauses[unsigned(CKind)].setPointer(Clause);
2298         Clauses.push_back(Clause);
2299       }
2300 
2301       // Skip ',' if any.
2302       if (Tok.is(tok::comma))
2303         ConsumeToken();
2304       Actions.EndOpenMPClause();
2305     }
2306     // End location of the directive.
2307     EndLoc = Tok.getLocation();
2308     // Consume final annot_pragma_openmp_end.
2309     ConsumeAnnotationToken();
2310 
2311     // OpenMP [2.13.8, ordered Construct, Syntax]
2312     // If the depend clause is specified, the ordered construct is a stand-alone
2313     // directive.
2314     if (DKind == OMPD_ordered && FirstClauses[unsigned(OMPC_depend)].getInt()) {
2315       if ((StmtCtx & ParsedStmtContext::AllowStandaloneOpenMPDirectives) ==
2316           ParsedStmtContext()) {
2317         Diag(Loc, diag::err_omp_immediate_directive)
2318             << getOpenMPDirectiveName(DKind) << 1
2319             << getOpenMPClauseName(OMPC_depend);
2320       }
2321       HasAssociatedStatement = false;
2322     }
2323 
2324     StmtResult AssociatedStmt;
2325     if (HasAssociatedStatement) {
2326       // The body is a block scope like in Lambdas and Blocks.
2327       Actions.ActOnOpenMPRegionStart(DKind, getCurScope());
2328       // FIXME: We create a bogus CompoundStmt scope to hold the contents of
2329       // the captured region. Code elsewhere assumes that any FunctionScopeInfo
2330       // should have at least one compound statement scope within it.
2331       ParsingOpenMPDirectiveRAII NormalScope(*this, /*Value=*/false);
2332       AssociatedStmt = (Sema::CompoundScopeRAII(Actions), ParseStatement());
2333       AssociatedStmt = Actions.ActOnOpenMPRegionEnd(AssociatedStmt, Clauses);
2334     } else if (DKind == OMPD_target_update || DKind == OMPD_target_enter_data ||
2335                DKind == OMPD_target_exit_data) {
2336       Actions.ActOnOpenMPRegionStart(DKind, getCurScope());
2337       AssociatedStmt = (Sema::CompoundScopeRAII(Actions),
2338                         Actions.ActOnCompoundStmt(Loc, Loc, llvm::None,
2339                                                   /*isStmtExpr=*/false));
2340       AssociatedStmt = Actions.ActOnOpenMPRegionEnd(AssociatedStmt, Clauses);
2341     }
2342     Directive = Actions.ActOnOpenMPExecutableDirective(
2343         DKind, DirName, CancelRegion, Clauses, AssociatedStmt.get(), Loc,
2344         EndLoc);
2345 
2346     // Exit scope.
2347     Actions.EndOpenMPDSABlock(Directive.get());
2348     OMPDirectiveScope.Exit();
2349     break;
2350   }
2351   case OMPD_declare_simd:
2352   case OMPD_declare_target:
2353   case OMPD_end_declare_target:
2354   case OMPD_requires:
2355   case OMPD_begin_declare_variant:
2356   case OMPD_end_declare_variant:
2357   case OMPD_declare_variant:
2358     Diag(Tok, diag::err_omp_unexpected_directive)
2359         << 1 << getOpenMPDirectiveName(DKind);
2360     SkipUntil(tok::annot_pragma_openmp_end);
2361     break;
2362   case OMPD_unknown:
2363   default:
2364     Diag(Tok, diag::err_omp_unknown_directive);
2365     SkipUntil(tok::annot_pragma_openmp_end);
2366     break;
2367   }
2368   return Directive;
2369 }
2370 
2371 // Parses simple list:
2372 //   simple-variable-list:
2373 //         '(' id-expression {, id-expression} ')'
2374 //
2375 bool Parser::ParseOpenMPSimpleVarList(
2376     OpenMPDirectiveKind Kind,
2377     const llvm::function_ref<void(CXXScopeSpec &, DeclarationNameInfo)> &
2378         Callback,
2379     bool AllowScopeSpecifier) {
2380   // Parse '('.
2381   BalancedDelimiterTracker T(*this, tok::l_paren, tok::annot_pragma_openmp_end);
2382   if (T.expectAndConsume(diag::err_expected_lparen_after,
2383                          getOpenMPDirectiveName(Kind).data()))
2384     return true;
2385   bool IsCorrect = true;
2386   bool NoIdentIsFound = true;
2387 
2388   // Read tokens while ')' or annot_pragma_openmp_end is not found.
2389   while (Tok.isNot(tok::r_paren) && Tok.isNot(tok::annot_pragma_openmp_end)) {
2390     CXXScopeSpec SS;
2391     UnqualifiedId Name;
2392     // Read var name.
2393     Token PrevTok = Tok;
2394     NoIdentIsFound = false;
2395 
2396     if (AllowScopeSpecifier && getLangOpts().CPlusPlus &&
2397         ParseOptionalCXXScopeSpecifier(SS, /*ObjectType=*/nullptr,
2398                                        /*ObjectHadErrors=*/false, false)) {
2399       IsCorrect = false;
2400       SkipUntil(tok::comma, tok::r_paren, tok::annot_pragma_openmp_end,
2401                 StopBeforeMatch);
2402     } else if (ParseUnqualifiedId(SS, /*ObjectType=*/nullptr,
2403                                   /*ObjectHadErrors=*/false, false, false,
2404                                   false, false, nullptr, Name)) {
2405       IsCorrect = false;
2406       SkipUntil(tok::comma, tok::r_paren, tok::annot_pragma_openmp_end,
2407                 StopBeforeMatch);
2408     } else if (Tok.isNot(tok::comma) && Tok.isNot(tok::r_paren) &&
2409                Tok.isNot(tok::annot_pragma_openmp_end)) {
2410       IsCorrect = false;
2411       SkipUntil(tok::comma, tok::r_paren, tok::annot_pragma_openmp_end,
2412                 StopBeforeMatch);
2413       Diag(PrevTok.getLocation(), diag::err_expected)
2414           << tok::identifier
2415           << SourceRange(PrevTok.getLocation(), PrevTokLocation);
2416     } else {
2417       Callback(SS, Actions.GetNameFromUnqualifiedId(Name));
2418     }
2419     // Consume ','.
2420     if (Tok.is(tok::comma)) {
2421       ConsumeToken();
2422     }
2423   }
2424 
2425   if (NoIdentIsFound) {
2426     Diag(Tok, diag::err_expected) << tok::identifier;
2427     IsCorrect = false;
2428   }
2429 
2430   // Parse ')'.
2431   IsCorrect = !T.consumeClose() && IsCorrect;
2432 
2433   return !IsCorrect;
2434 }
2435 
2436 OMPClause *Parser::ParseOpenMPUsesAllocatorClause(OpenMPDirectiveKind DKind) {
2437   SourceLocation Loc = Tok.getLocation();
2438   ConsumeAnyToken();
2439 
2440   // Parse '('.
2441   BalancedDelimiterTracker T(*this, tok::l_paren, tok::annot_pragma_openmp_end);
2442   if (T.expectAndConsume(diag::err_expected_lparen_after, "uses_allocator"))
2443     return nullptr;
2444   SmallVector<Sema::UsesAllocatorsData, 4> Data;
2445   do {
2446     ExprResult Allocator = ParseCXXIdExpression();
2447     if (Allocator.isInvalid()) {
2448       SkipUntil(tok::comma, tok::r_paren, tok::annot_pragma_openmp_end,
2449                 StopBeforeMatch);
2450       break;
2451     }
2452     Sema::UsesAllocatorsData &D = Data.emplace_back();
2453     D.Allocator = Allocator.get();
2454     if (Tok.is(tok::l_paren)) {
2455       BalancedDelimiterTracker T(*this, tok::l_paren,
2456                                  tok::annot_pragma_openmp_end);
2457       T.consumeOpen();
2458       ExprResult AllocatorTraits = ParseCXXIdExpression();
2459       T.consumeClose();
2460       if (AllocatorTraits.isInvalid()) {
2461         SkipUntil(tok::comma, tok::r_paren, tok::annot_pragma_openmp_end,
2462                   StopBeforeMatch);
2463         break;
2464       }
2465       D.AllocatorTraits = AllocatorTraits.get();
2466       D.LParenLoc = T.getOpenLocation();
2467       D.RParenLoc = T.getCloseLocation();
2468     }
2469     if (Tok.isNot(tok::comma) && Tok.isNot(tok::r_paren))
2470       Diag(Tok, diag::err_omp_expected_punc) << "uses_allocators" << 0;
2471     // Parse ','
2472     if (Tok.is(tok::comma))
2473       ConsumeAnyToken();
2474   } while (Tok.isNot(tok::r_paren) && Tok.isNot(tok::annot_pragma_openmp_end));
2475   T.consumeClose();
2476   return Actions.ActOnOpenMPUsesAllocatorClause(Loc, T.getOpenLocation(),
2477                                                 T.getCloseLocation(), Data);
2478 }
2479 
2480 /// Parsing of OpenMP clauses.
2481 ///
2482 ///    clause:
2483 ///       if-clause | final-clause | num_threads-clause | safelen-clause |
2484 ///       default-clause | private-clause | firstprivate-clause | shared-clause
2485 ///       | linear-clause | aligned-clause | collapse-clause |
2486 ///       lastprivate-clause | reduction-clause | proc_bind-clause |
2487 ///       schedule-clause | copyin-clause | copyprivate-clause | untied-clause |
2488 ///       mergeable-clause | flush-clause | read-clause | write-clause |
2489 ///       update-clause | capture-clause | seq_cst-clause | device-clause |
2490 ///       simdlen-clause | threads-clause | simd-clause | num_teams-clause |
2491 ///       thread_limit-clause | priority-clause | grainsize-clause |
2492 ///       nogroup-clause | num_tasks-clause | hint-clause | to-clause |
2493 ///       from-clause | is_device_ptr-clause | task_reduction-clause |
2494 ///       in_reduction-clause | allocator-clause | allocate-clause |
2495 ///       acq_rel-clause | acquire-clause | release-clause | relaxed-clause |
2496 ///       depobj-clause | destroy-clause | detach-clause | inclusive-clause |
2497 ///       exclusive-clause | uses_allocators-clause | use_device_addr-clause
2498 ///
2499 OMPClause *Parser::ParseOpenMPClause(OpenMPDirectiveKind DKind,
2500                                      OpenMPClauseKind CKind, bool FirstClause) {
2501   OMPClauseKind = CKind;
2502   OMPClause *Clause = nullptr;
2503   bool ErrorFound = false;
2504   bool WrongDirective = false;
2505   // Check if clause is allowed for the given directive.
2506   if (CKind != OMPC_unknown &&
2507       !isAllowedClauseForDirective(DKind, CKind, getLangOpts().OpenMP)) {
2508     Diag(Tok, diag::err_omp_unexpected_clause) << getOpenMPClauseName(CKind)
2509                                                << getOpenMPDirectiveName(DKind);
2510     ErrorFound = true;
2511     WrongDirective = true;
2512   }
2513 
2514   switch (CKind) {
2515   case OMPC_final:
2516   case OMPC_num_threads:
2517   case OMPC_safelen:
2518   case OMPC_simdlen:
2519   case OMPC_collapse:
2520   case OMPC_ordered:
2521   case OMPC_num_teams:
2522   case OMPC_thread_limit:
2523   case OMPC_priority:
2524   case OMPC_grainsize:
2525   case OMPC_num_tasks:
2526   case OMPC_hint:
2527   case OMPC_allocator:
2528   case OMPC_depobj:
2529   case OMPC_detach:
2530     // OpenMP [2.5, Restrictions]
2531     //  At most one num_threads clause can appear on the directive.
2532     // OpenMP [2.8.1, simd construct, Restrictions]
2533     //  Only one safelen  clause can appear on a simd directive.
2534     //  Only one simdlen  clause can appear on a simd directive.
2535     //  Only one collapse clause can appear on a simd directive.
2536     // OpenMP [2.11.1, task Construct, Restrictions]
2537     //  At most one if clause can appear on the directive.
2538     //  At most one final clause can appear on the directive.
2539     // OpenMP [teams Construct, Restrictions]
2540     //  At most one num_teams clause can appear on the directive.
2541     //  At most one thread_limit clause can appear on the directive.
2542     // OpenMP [2.9.1, task Construct, Restrictions]
2543     // At most one priority clause can appear on the directive.
2544     // OpenMP [2.9.2, taskloop Construct, Restrictions]
2545     // At most one grainsize clause can appear on the directive.
2546     // OpenMP [2.9.2, taskloop Construct, Restrictions]
2547     // At most one num_tasks clause can appear on the directive.
2548     // OpenMP [2.11.3, allocate Directive, Restrictions]
2549     // At most one allocator clause can appear on the directive.
2550     // OpenMP 5.0, 2.10.1 task Construct, Restrictions.
2551     // At most one detach clause can appear on the directive.
2552     if (!FirstClause) {
2553       Diag(Tok, diag::err_omp_more_one_clause)
2554           << getOpenMPDirectiveName(DKind) << getOpenMPClauseName(CKind) << 0;
2555       ErrorFound = true;
2556     }
2557 
2558     if (CKind == OMPC_ordered && PP.LookAhead(/*N=*/0).isNot(tok::l_paren))
2559       Clause = ParseOpenMPClause(CKind, WrongDirective);
2560     else
2561       Clause = ParseOpenMPSingleExprClause(CKind, WrongDirective);
2562     break;
2563   case OMPC_default:
2564   case OMPC_proc_bind:
2565   case OMPC_atomic_default_mem_order:
2566   case OMPC_order:
2567     // OpenMP [2.14.3.1, Restrictions]
2568     //  Only a single default clause may be specified on a parallel, task or
2569     //  teams directive.
2570     // OpenMP [2.5, parallel Construct, Restrictions]
2571     //  At most one proc_bind clause can appear on the directive.
2572     // OpenMP [5.0, Requires directive, Restrictions]
2573     //  At most one atomic_default_mem_order clause can appear
2574     //  on the directive
2575     if (!FirstClause && CKind != OMPC_order) {
2576       Diag(Tok, diag::err_omp_more_one_clause)
2577           << getOpenMPDirectiveName(DKind) << getOpenMPClauseName(CKind) << 0;
2578       ErrorFound = true;
2579     }
2580 
2581     Clause = ParseOpenMPSimpleClause(CKind, WrongDirective);
2582     break;
2583   case OMPC_device:
2584   case OMPC_schedule:
2585   case OMPC_dist_schedule:
2586   case OMPC_defaultmap:
2587     // OpenMP [2.7.1, Restrictions, p. 3]
2588     //  Only one schedule clause can appear on a loop directive.
2589     // OpenMP 4.5 [2.10.4, Restrictions, p. 106]
2590     //  At most one defaultmap clause can appear on the directive.
2591     // OpenMP 5.0 [2.12.5, target construct, Restrictions]
2592     //  At most one device clause can appear on the directive.
2593     if ((getLangOpts().OpenMP < 50 || CKind != OMPC_defaultmap) &&
2594         !FirstClause) {
2595       Diag(Tok, diag::err_omp_more_one_clause)
2596           << getOpenMPDirectiveName(DKind) << getOpenMPClauseName(CKind) << 0;
2597       ErrorFound = true;
2598     }
2599     LLVM_FALLTHROUGH;
2600   case OMPC_if:
2601     Clause = ParseOpenMPSingleExprWithArgClause(DKind, CKind, WrongDirective);
2602     break;
2603   case OMPC_nowait:
2604   case OMPC_untied:
2605   case OMPC_mergeable:
2606   case OMPC_read:
2607   case OMPC_write:
2608   case OMPC_capture:
2609   case OMPC_seq_cst:
2610   case OMPC_acq_rel:
2611   case OMPC_acquire:
2612   case OMPC_release:
2613   case OMPC_relaxed:
2614   case OMPC_threads:
2615   case OMPC_simd:
2616   case OMPC_nogroup:
2617   case OMPC_unified_address:
2618   case OMPC_unified_shared_memory:
2619   case OMPC_reverse_offload:
2620   case OMPC_dynamic_allocators:
2621   case OMPC_destroy:
2622     // OpenMP [2.7.1, Restrictions, p. 9]
2623     //  Only one ordered clause can appear on a loop directive.
2624     // OpenMP [2.7.1, Restrictions, C/C++, p. 4]
2625     //  Only one nowait clause can appear on a for directive.
2626     // OpenMP [5.0, Requires directive, Restrictions]
2627     //   Each of the requires clauses can appear at most once on the directive.
2628     if (!FirstClause) {
2629       Diag(Tok, diag::err_omp_more_one_clause)
2630           << getOpenMPDirectiveName(DKind) << getOpenMPClauseName(CKind) << 0;
2631       ErrorFound = true;
2632     }
2633 
2634     Clause = ParseOpenMPClause(CKind, WrongDirective);
2635     break;
2636   case OMPC_update:
2637     if (!FirstClause) {
2638       Diag(Tok, diag::err_omp_more_one_clause)
2639           << getOpenMPDirectiveName(DKind) << getOpenMPClauseName(CKind) << 0;
2640       ErrorFound = true;
2641     }
2642 
2643     Clause = (DKind == OMPD_depobj)
2644                  ? ParseOpenMPSimpleClause(CKind, WrongDirective)
2645                  : ParseOpenMPClause(CKind, WrongDirective);
2646     break;
2647   case OMPC_private:
2648   case OMPC_firstprivate:
2649   case OMPC_lastprivate:
2650   case OMPC_shared:
2651   case OMPC_reduction:
2652   case OMPC_task_reduction:
2653   case OMPC_in_reduction:
2654   case OMPC_linear:
2655   case OMPC_aligned:
2656   case OMPC_copyin:
2657   case OMPC_copyprivate:
2658   case OMPC_flush:
2659   case OMPC_depend:
2660   case OMPC_map:
2661   case OMPC_to:
2662   case OMPC_from:
2663   case OMPC_use_device_ptr:
2664   case OMPC_use_device_addr:
2665   case OMPC_is_device_ptr:
2666   case OMPC_allocate:
2667   case OMPC_nontemporal:
2668   case OMPC_inclusive:
2669   case OMPC_exclusive:
2670   case OMPC_affinity:
2671     Clause = ParseOpenMPVarListClause(DKind, CKind, WrongDirective);
2672     break;
2673   case OMPC_uses_allocators:
2674     Clause = ParseOpenMPUsesAllocatorClause(DKind);
2675     break;
2676   case OMPC_device_type:
2677   case OMPC_unknown:
2678     skipUntilPragmaOpenMPEnd(DKind);
2679     break;
2680   case OMPC_threadprivate:
2681   case OMPC_uniform:
2682   case OMPC_match:
2683     if (!WrongDirective)
2684       Diag(Tok, diag::err_omp_unexpected_clause)
2685           << getOpenMPClauseName(CKind) << getOpenMPDirectiveName(DKind);
2686     SkipUntil(tok::comma, tok::annot_pragma_openmp_end, StopBeforeMatch);
2687     break;
2688   default:
2689     break;
2690   }
2691   return ErrorFound ? nullptr : Clause;
2692 }
2693 
2694 /// Parses simple expression in parens for single-expression clauses of OpenMP
2695 /// constructs.
2696 /// \param RLoc Returned location of right paren.
2697 ExprResult Parser::ParseOpenMPParensExpr(StringRef ClauseName,
2698                                          SourceLocation &RLoc,
2699                                          bool IsAddressOfOperand) {
2700   BalancedDelimiterTracker T(*this, tok::l_paren, tok::annot_pragma_openmp_end);
2701   if (T.expectAndConsume(diag::err_expected_lparen_after, ClauseName.data()))
2702     return ExprError();
2703 
2704   SourceLocation ELoc = Tok.getLocation();
2705   ExprResult LHS(ParseCastExpression(AnyCastExpr, IsAddressOfOperand,
2706                                      NotTypeCast));
2707   ExprResult Val(ParseRHSOfBinaryExpression(LHS, prec::Conditional));
2708   Val = Actions.ActOnFinishFullExpr(Val.get(), ELoc, /*DiscardedValue*/ false);
2709 
2710   // Parse ')'.
2711   RLoc = Tok.getLocation();
2712   if (!T.consumeClose())
2713     RLoc = T.getCloseLocation();
2714 
2715   return Val;
2716 }
2717 
2718 /// Parsing of OpenMP clauses with single expressions like 'final',
2719 /// 'collapse', 'safelen', 'num_threads', 'simdlen', 'num_teams',
2720 /// 'thread_limit', 'simdlen', 'priority', 'grainsize', 'num_tasks', 'hint' or
2721 /// 'detach'.
2722 ///
2723 ///    final-clause:
2724 ///      'final' '(' expression ')'
2725 ///
2726 ///    num_threads-clause:
2727 ///      'num_threads' '(' expression ')'
2728 ///
2729 ///    safelen-clause:
2730 ///      'safelen' '(' expression ')'
2731 ///
2732 ///    simdlen-clause:
2733 ///      'simdlen' '(' expression ')'
2734 ///
2735 ///    collapse-clause:
2736 ///      'collapse' '(' expression ')'
2737 ///
2738 ///    priority-clause:
2739 ///      'priority' '(' expression ')'
2740 ///
2741 ///    grainsize-clause:
2742 ///      'grainsize' '(' expression ')'
2743 ///
2744 ///    num_tasks-clause:
2745 ///      'num_tasks' '(' expression ')'
2746 ///
2747 ///    hint-clause:
2748 ///      'hint' '(' expression ')'
2749 ///
2750 ///    allocator-clause:
2751 ///      'allocator' '(' expression ')'
2752 ///
2753 ///    detach-clause:
2754 ///      'detach' '(' event-handler-expression ')'
2755 ///
2756 OMPClause *Parser::ParseOpenMPSingleExprClause(OpenMPClauseKind Kind,
2757                                                bool ParseOnly) {
2758   SourceLocation Loc = ConsumeToken();
2759   SourceLocation LLoc = Tok.getLocation();
2760   SourceLocation RLoc;
2761 
2762   ExprResult Val = ParseOpenMPParensExpr(getOpenMPClauseName(Kind), RLoc);
2763 
2764   if (Val.isInvalid())
2765     return nullptr;
2766 
2767   if (ParseOnly)
2768     return nullptr;
2769   return Actions.ActOnOpenMPSingleExprClause(Kind, Val.get(), Loc, LLoc, RLoc);
2770 }
2771 
2772 /// Parsing of simple OpenMP clauses like 'default' or 'proc_bind'.
2773 ///
2774 ///    default-clause:
2775 ///         'default' '(' 'none' | 'shared' | 'firstprivate' ')'
2776 ///
2777 ///    proc_bind-clause:
2778 ///         'proc_bind' '(' 'master' | 'close' | 'spread' ')'
2779 ///
2780 ///    update-clause:
2781 ///         'update' '(' 'in' | 'out' | 'inout' | 'mutexinoutset' ')'
2782 ///
2783 OMPClause *Parser::ParseOpenMPSimpleClause(OpenMPClauseKind Kind,
2784                                            bool ParseOnly) {
2785   llvm::Optional<SimpleClauseData> Val = parseOpenMPSimpleClause(*this, Kind);
2786   if (!Val || ParseOnly)
2787     return nullptr;
2788   if (getLangOpts().OpenMP < 51 && Kind == OMPC_default &&
2789       static_cast<DefaultKind>(Val.getValue().Type) ==
2790           OMP_DEFAULT_firstprivate) {
2791     Diag(Val.getValue().LOpen, diag::err_omp_invalid_dsa)
2792         << getOpenMPClauseName(OMPC_firstprivate)
2793         << getOpenMPClauseName(OMPC_default) << "5.1";
2794     return nullptr;
2795   }
2796   return Actions.ActOnOpenMPSimpleClause(
2797       Kind, Val.getValue().Type, Val.getValue().TypeLoc, Val.getValue().LOpen,
2798       Val.getValue().Loc, Val.getValue().RLoc);
2799 }
2800 
2801 /// Parsing of OpenMP clauses like 'ordered'.
2802 ///
2803 ///    ordered-clause:
2804 ///         'ordered'
2805 ///
2806 ///    nowait-clause:
2807 ///         'nowait'
2808 ///
2809 ///    untied-clause:
2810 ///         'untied'
2811 ///
2812 ///    mergeable-clause:
2813 ///         'mergeable'
2814 ///
2815 ///    read-clause:
2816 ///         'read'
2817 ///
2818 ///    threads-clause:
2819 ///         'threads'
2820 ///
2821 ///    simd-clause:
2822 ///         'simd'
2823 ///
2824 ///    nogroup-clause:
2825 ///         'nogroup'
2826 ///
2827 OMPClause *Parser::ParseOpenMPClause(OpenMPClauseKind Kind, bool ParseOnly) {
2828   SourceLocation Loc = Tok.getLocation();
2829   ConsumeAnyToken();
2830 
2831   if (ParseOnly)
2832     return nullptr;
2833   return Actions.ActOnOpenMPClause(Kind, Loc, Tok.getLocation());
2834 }
2835 
2836 /// Parsing of OpenMP clauses with single expressions and some additional
2837 /// argument like 'schedule' or 'dist_schedule'.
2838 ///
2839 ///    schedule-clause:
2840 ///      'schedule' '(' [ modifier [ ',' modifier ] ':' ] kind [',' expression ]
2841 ///      ')'
2842 ///
2843 ///    if-clause:
2844 ///      'if' '(' [ directive-name-modifier ':' ] expression ')'
2845 ///
2846 ///    defaultmap:
2847 ///      'defaultmap' '(' modifier [ ':' kind ] ')'
2848 ///
2849 ///    device-clause:
2850 ///      'device' '(' [ device-modifier ':' ] expression ')'
2851 ///
2852 OMPClause *Parser::ParseOpenMPSingleExprWithArgClause(OpenMPDirectiveKind DKind,
2853                                                       OpenMPClauseKind Kind,
2854                                                       bool ParseOnly) {
2855   SourceLocation Loc = ConsumeToken();
2856   SourceLocation DelimLoc;
2857   // Parse '('.
2858   BalancedDelimiterTracker T(*this, tok::l_paren, tok::annot_pragma_openmp_end);
2859   if (T.expectAndConsume(diag::err_expected_lparen_after,
2860                          getOpenMPClauseName(Kind).data()))
2861     return nullptr;
2862 
2863   ExprResult Val;
2864   SmallVector<unsigned, 4> Arg;
2865   SmallVector<SourceLocation, 4> KLoc;
2866   if (Kind == OMPC_schedule) {
2867     enum { Modifier1, Modifier2, ScheduleKind, NumberOfElements };
2868     Arg.resize(NumberOfElements);
2869     KLoc.resize(NumberOfElements);
2870     Arg[Modifier1] = OMPC_SCHEDULE_MODIFIER_unknown;
2871     Arg[Modifier2] = OMPC_SCHEDULE_MODIFIER_unknown;
2872     Arg[ScheduleKind] = OMPC_SCHEDULE_unknown;
2873     unsigned KindModifier = getOpenMPSimpleClauseType(
2874         Kind, Tok.isAnnotation() ? "" : PP.getSpelling(Tok));
2875     if (KindModifier > OMPC_SCHEDULE_unknown) {
2876       // Parse 'modifier'
2877       Arg[Modifier1] = KindModifier;
2878       KLoc[Modifier1] = Tok.getLocation();
2879       if (Tok.isNot(tok::r_paren) && Tok.isNot(tok::comma) &&
2880           Tok.isNot(tok::annot_pragma_openmp_end))
2881         ConsumeAnyToken();
2882       if (Tok.is(tok::comma)) {
2883         // Parse ',' 'modifier'
2884         ConsumeAnyToken();
2885         KindModifier = getOpenMPSimpleClauseType(
2886             Kind, Tok.isAnnotation() ? "" : PP.getSpelling(Tok));
2887         Arg[Modifier2] = KindModifier > OMPC_SCHEDULE_unknown
2888                              ? KindModifier
2889                              : (unsigned)OMPC_SCHEDULE_unknown;
2890         KLoc[Modifier2] = Tok.getLocation();
2891         if (Tok.isNot(tok::r_paren) && Tok.isNot(tok::comma) &&
2892             Tok.isNot(tok::annot_pragma_openmp_end))
2893           ConsumeAnyToken();
2894       }
2895       // Parse ':'
2896       if (Tok.is(tok::colon))
2897         ConsumeAnyToken();
2898       else
2899         Diag(Tok, diag::warn_pragma_expected_colon) << "schedule modifier";
2900       KindModifier = getOpenMPSimpleClauseType(
2901           Kind, Tok.isAnnotation() ? "" : PP.getSpelling(Tok));
2902     }
2903     Arg[ScheduleKind] = KindModifier;
2904     KLoc[ScheduleKind] = Tok.getLocation();
2905     if (Tok.isNot(tok::r_paren) && Tok.isNot(tok::comma) &&
2906         Tok.isNot(tok::annot_pragma_openmp_end))
2907       ConsumeAnyToken();
2908     if ((Arg[ScheduleKind] == OMPC_SCHEDULE_static ||
2909          Arg[ScheduleKind] == OMPC_SCHEDULE_dynamic ||
2910          Arg[ScheduleKind] == OMPC_SCHEDULE_guided) &&
2911         Tok.is(tok::comma))
2912       DelimLoc = ConsumeAnyToken();
2913   } else if (Kind == OMPC_dist_schedule) {
2914     Arg.push_back(getOpenMPSimpleClauseType(
2915         Kind, Tok.isAnnotation() ? "" : PP.getSpelling(Tok)));
2916     KLoc.push_back(Tok.getLocation());
2917     if (Tok.isNot(tok::r_paren) && Tok.isNot(tok::comma) &&
2918         Tok.isNot(tok::annot_pragma_openmp_end))
2919       ConsumeAnyToken();
2920     if (Arg.back() == OMPC_DIST_SCHEDULE_static && Tok.is(tok::comma))
2921       DelimLoc = ConsumeAnyToken();
2922   } else if (Kind == OMPC_defaultmap) {
2923     // Get a defaultmap modifier
2924     unsigned Modifier = getOpenMPSimpleClauseType(
2925         Kind, Tok.isAnnotation() ? "" : PP.getSpelling(Tok));
2926     // Set defaultmap modifier to unknown if it is either scalar, aggregate, or
2927     // pointer
2928     if (Modifier < OMPC_DEFAULTMAP_MODIFIER_unknown)
2929       Modifier = OMPC_DEFAULTMAP_MODIFIER_unknown;
2930     Arg.push_back(Modifier);
2931     KLoc.push_back(Tok.getLocation());
2932     if (Tok.isNot(tok::r_paren) && Tok.isNot(tok::comma) &&
2933         Tok.isNot(tok::annot_pragma_openmp_end))
2934       ConsumeAnyToken();
2935     // Parse ':'
2936     if (Tok.is(tok::colon) || getLangOpts().OpenMP < 50) {
2937       if (Tok.is(tok::colon))
2938         ConsumeAnyToken();
2939       else if (Arg.back() != OMPC_DEFAULTMAP_MODIFIER_unknown)
2940         Diag(Tok, diag::warn_pragma_expected_colon) << "defaultmap modifier";
2941       // Get a defaultmap kind
2942       Arg.push_back(getOpenMPSimpleClauseType(
2943           Kind, Tok.isAnnotation() ? "" : PP.getSpelling(Tok)));
2944       KLoc.push_back(Tok.getLocation());
2945       if (Tok.isNot(tok::r_paren) && Tok.isNot(tok::comma) &&
2946           Tok.isNot(tok::annot_pragma_openmp_end))
2947         ConsumeAnyToken();
2948     } else {
2949       Arg.push_back(OMPC_DEFAULTMAP_unknown);
2950       KLoc.push_back(SourceLocation());
2951     }
2952   } else if (Kind == OMPC_device) {
2953     // Only target executable directives support extended device construct.
2954     if (isOpenMPTargetExecutionDirective(DKind) && getLangOpts().OpenMP >= 50 &&
2955         NextToken().is(tok::colon)) {
2956       // Parse optional <device modifier> ':'
2957       Arg.push_back(getOpenMPSimpleClauseType(
2958           Kind, Tok.isAnnotation() ? "" : PP.getSpelling(Tok)));
2959       KLoc.push_back(Tok.getLocation());
2960       ConsumeAnyToken();
2961       // Parse ':'
2962       ConsumeAnyToken();
2963     } else {
2964       Arg.push_back(OMPC_DEVICE_unknown);
2965       KLoc.emplace_back();
2966     }
2967   } else {
2968     assert(Kind == OMPC_if);
2969     KLoc.push_back(Tok.getLocation());
2970     TentativeParsingAction TPA(*this);
2971     auto DK = parseOpenMPDirectiveKind(*this);
2972     Arg.push_back(DK);
2973     if (DK != OMPD_unknown) {
2974       ConsumeToken();
2975       if (Tok.is(tok::colon) && getLangOpts().OpenMP > 40) {
2976         TPA.Commit();
2977         DelimLoc = ConsumeToken();
2978       } else {
2979         TPA.Revert();
2980         Arg.back() = unsigned(OMPD_unknown);
2981       }
2982     } else {
2983       TPA.Revert();
2984     }
2985   }
2986 
2987   bool NeedAnExpression = (Kind == OMPC_schedule && DelimLoc.isValid()) ||
2988                           (Kind == OMPC_dist_schedule && DelimLoc.isValid()) ||
2989                           Kind == OMPC_if || Kind == OMPC_device;
2990   if (NeedAnExpression) {
2991     SourceLocation ELoc = Tok.getLocation();
2992     ExprResult LHS(ParseCastExpression(AnyCastExpr, false, NotTypeCast));
2993     Val = ParseRHSOfBinaryExpression(LHS, prec::Conditional);
2994     Val =
2995         Actions.ActOnFinishFullExpr(Val.get(), ELoc, /*DiscardedValue*/ false);
2996   }
2997 
2998   // Parse ')'.
2999   SourceLocation RLoc = Tok.getLocation();
3000   if (!T.consumeClose())
3001     RLoc = T.getCloseLocation();
3002 
3003   if (NeedAnExpression && Val.isInvalid())
3004     return nullptr;
3005 
3006   if (ParseOnly)
3007     return nullptr;
3008   return Actions.ActOnOpenMPSingleExprWithArgClause(
3009       Kind, Arg, Val.get(), Loc, T.getOpenLocation(), KLoc, DelimLoc, RLoc);
3010 }
3011 
3012 static bool ParseReductionId(Parser &P, CXXScopeSpec &ReductionIdScopeSpec,
3013                              UnqualifiedId &ReductionId) {
3014   if (ReductionIdScopeSpec.isEmpty()) {
3015     auto OOK = OO_None;
3016     switch (P.getCurToken().getKind()) {
3017     case tok::plus:
3018       OOK = OO_Plus;
3019       break;
3020     case tok::minus:
3021       OOK = OO_Minus;
3022       break;
3023     case tok::star:
3024       OOK = OO_Star;
3025       break;
3026     case tok::amp:
3027       OOK = OO_Amp;
3028       break;
3029     case tok::pipe:
3030       OOK = OO_Pipe;
3031       break;
3032     case tok::caret:
3033       OOK = OO_Caret;
3034       break;
3035     case tok::ampamp:
3036       OOK = OO_AmpAmp;
3037       break;
3038     case tok::pipepipe:
3039       OOK = OO_PipePipe;
3040       break;
3041     default:
3042       break;
3043     }
3044     if (OOK != OO_None) {
3045       SourceLocation OpLoc = P.ConsumeToken();
3046       SourceLocation SymbolLocations[] = {OpLoc, OpLoc, SourceLocation()};
3047       ReductionId.setOperatorFunctionId(OpLoc, OOK, SymbolLocations);
3048       return false;
3049     }
3050   }
3051   return P.ParseUnqualifiedId(
3052       ReductionIdScopeSpec, /*ObjectType=*/nullptr,
3053       /*ObjectHadErrors=*/false, /*EnteringContext*/ false,
3054       /*AllowDestructorName*/ false,
3055       /*AllowConstructorName*/ false,
3056       /*AllowDeductionGuide*/ false, nullptr, ReductionId);
3057 }
3058 
3059 /// Checks if the token is a valid map-type-modifier.
3060 static OpenMPMapModifierKind isMapModifier(Parser &P) {
3061   Token Tok = P.getCurToken();
3062   if (!Tok.is(tok::identifier))
3063     return OMPC_MAP_MODIFIER_unknown;
3064 
3065   Preprocessor &PP = P.getPreprocessor();
3066   OpenMPMapModifierKind TypeModifier = static_cast<OpenMPMapModifierKind>(
3067       getOpenMPSimpleClauseType(OMPC_map, PP.getSpelling(Tok)));
3068   return TypeModifier;
3069 }
3070 
3071 /// Parse the mapper modifier in map, to, and from clauses.
3072 bool Parser::parseMapperModifier(OpenMPVarListDataTy &Data) {
3073   // Parse '('.
3074   BalancedDelimiterTracker T(*this, tok::l_paren, tok::colon);
3075   if (T.expectAndConsume(diag::err_expected_lparen_after, "mapper")) {
3076     SkipUntil(tok::colon, tok::r_paren, tok::annot_pragma_openmp_end,
3077               StopBeforeMatch);
3078     return true;
3079   }
3080   // Parse mapper-identifier
3081   if (getLangOpts().CPlusPlus)
3082     ParseOptionalCXXScopeSpecifier(Data.ReductionOrMapperIdScopeSpec,
3083                                    /*ObjectType=*/nullptr,
3084                                    /*ObjectHadErrors=*/false,
3085                                    /*EnteringContext=*/false);
3086   if (Tok.isNot(tok::identifier) && Tok.isNot(tok::kw_default)) {
3087     Diag(Tok.getLocation(), diag::err_omp_mapper_illegal_identifier);
3088     SkipUntil(tok::colon, tok::r_paren, tok::annot_pragma_openmp_end,
3089               StopBeforeMatch);
3090     return true;
3091   }
3092   auto &DeclNames = Actions.getASTContext().DeclarationNames;
3093   Data.ReductionOrMapperId = DeclarationNameInfo(
3094       DeclNames.getIdentifier(Tok.getIdentifierInfo()), Tok.getLocation());
3095   ConsumeToken();
3096   // Parse ')'.
3097   return T.consumeClose();
3098 }
3099 
3100 /// Parse map-type-modifiers in map clause.
3101 /// map([ [map-type-modifier[,] [map-type-modifier[,] ...] map-type : ] list)
3102 /// where, map-type-modifier ::= always | close | mapper(mapper-identifier)
3103 bool Parser::parseMapTypeModifiers(OpenMPVarListDataTy &Data) {
3104   while (getCurToken().isNot(tok::colon)) {
3105     OpenMPMapModifierKind TypeModifier = isMapModifier(*this);
3106     if (TypeModifier == OMPC_MAP_MODIFIER_always ||
3107         TypeModifier == OMPC_MAP_MODIFIER_close) {
3108       Data.MapTypeModifiers.push_back(TypeModifier);
3109       Data.MapTypeModifiersLoc.push_back(Tok.getLocation());
3110       ConsumeToken();
3111     } else if (TypeModifier == OMPC_MAP_MODIFIER_mapper) {
3112       Data.MapTypeModifiers.push_back(TypeModifier);
3113       Data.MapTypeModifiersLoc.push_back(Tok.getLocation());
3114       ConsumeToken();
3115       if (parseMapperModifier(Data))
3116         return true;
3117     } else {
3118       // For the case of unknown map-type-modifier or a map-type.
3119       // Map-type is followed by a colon; the function returns when it
3120       // encounters a token followed by a colon.
3121       if (Tok.is(tok::comma)) {
3122         Diag(Tok, diag::err_omp_map_type_modifier_missing);
3123         ConsumeToken();
3124         continue;
3125       }
3126       // Potential map-type token as it is followed by a colon.
3127       if (PP.LookAhead(0).is(tok::colon))
3128         return false;
3129       Diag(Tok, diag::err_omp_unknown_map_type_modifier);
3130       ConsumeToken();
3131     }
3132     if (getCurToken().is(tok::comma))
3133       ConsumeToken();
3134   }
3135   return false;
3136 }
3137 
3138 /// Checks if the token is a valid map-type.
3139 static OpenMPMapClauseKind isMapType(Parser &P) {
3140   Token Tok = P.getCurToken();
3141   // The map-type token can be either an identifier or the C++ delete keyword.
3142   if (!Tok.isOneOf(tok::identifier, tok::kw_delete))
3143     return OMPC_MAP_unknown;
3144   Preprocessor &PP = P.getPreprocessor();
3145   OpenMPMapClauseKind MapType = static_cast<OpenMPMapClauseKind>(
3146       getOpenMPSimpleClauseType(OMPC_map, PP.getSpelling(Tok)));
3147   return MapType;
3148 }
3149 
3150 /// Parse map-type in map clause.
3151 /// map([ [map-type-modifier[,] [map-type-modifier[,] ...] map-type : ] list)
3152 /// where, map-type ::= to | from | tofrom | alloc | release | delete
3153 static void parseMapType(Parser &P, Parser::OpenMPVarListDataTy &Data) {
3154   Token Tok = P.getCurToken();
3155   if (Tok.is(tok::colon)) {
3156     P.Diag(Tok, diag::err_omp_map_type_missing);
3157     return;
3158   }
3159   Data.ExtraModifier = isMapType(P);
3160   if (Data.ExtraModifier == OMPC_MAP_unknown)
3161     P.Diag(Tok, diag::err_omp_unknown_map_type);
3162   P.ConsumeToken();
3163 }
3164 
3165 /// Parses simple expression in parens for single-expression clauses of OpenMP
3166 /// constructs.
3167 /// \param RLoc Returned location of right paren.
3168 ExprResult Parser::ParseOpenMPIteratorsExpr() {
3169   assert(Tok.is(tok::identifier) && PP.getSpelling(Tok) == "iterator" &&
3170          "Expected 'iterator' token.");
3171   SourceLocation IteratorKwLoc = ConsumeToken();
3172 
3173   BalancedDelimiterTracker T(*this, tok::l_paren, tok::annot_pragma_openmp_end);
3174   if (T.expectAndConsume(diag::err_expected_lparen_after, "iterator"))
3175     return ExprError();
3176 
3177   SourceLocation LLoc = T.getOpenLocation();
3178   SmallVector<Sema::OMPIteratorData, 4> Data;
3179   while (Tok.isNot(tok::r_paren) && Tok.isNot(tok::annot_pragma_openmp_end)) {
3180     // Check if the type parsing is required.
3181     ParsedType IteratorType;
3182     if (Tok.isNot(tok::identifier) || NextToken().isNot(tok::equal)) {
3183       // identifier '=' is not found - parse type.
3184       TypeResult TR = ParseTypeName();
3185       if (TR.isInvalid()) {
3186         T.skipToEnd();
3187         return ExprError();
3188       }
3189       IteratorType = TR.get();
3190     }
3191 
3192     // Parse identifier.
3193     IdentifierInfo *II = nullptr;
3194     SourceLocation IdLoc;
3195     if (Tok.is(tok::identifier)) {
3196       II = Tok.getIdentifierInfo();
3197       IdLoc = ConsumeToken();
3198     } else {
3199       Diag(Tok, diag::err_expected_unqualified_id) << 0;
3200     }
3201 
3202     // Parse '='.
3203     SourceLocation AssignLoc;
3204     if (Tok.is(tok::equal))
3205       AssignLoc = ConsumeToken();
3206     else
3207       Diag(Tok, diag::err_omp_expected_equal_in_iterator);
3208 
3209     // Parse range-specification - <begin> ':' <end> [ ':' <step> ]
3210     ColonProtectionRAIIObject ColonRAII(*this);
3211     // Parse <begin>
3212     SourceLocation Loc = Tok.getLocation();
3213     ExprResult LHS = ParseCastExpression(AnyCastExpr);
3214     ExprResult Begin = Actions.CorrectDelayedTyposInExpr(
3215         ParseRHSOfBinaryExpression(LHS, prec::Conditional));
3216     Begin = Actions.ActOnFinishFullExpr(Begin.get(), Loc,
3217                                         /*DiscardedValue=*/false);
3218     // Parse ':'.
3219     SourceLocation ColonLoc;
3220     if (Tok.is(tok::colon))
3221       ColonLoc = ConsumeToken();
3222 
3223     // Parse <end>
3224     Loc = Tok.getLocation();
3225     LHS = ParseCastExpression(AnyCastExpr);
3226     ExprResult End = Actions.CorrectDelayedTyposInExpr(
3227         ParseRHSOfBinaryExpression(LHS, prec::Conditional));
3228     End = Actions.ActOnFinishFullExpr(End.get(), Loc,
3229                                       /*DiscardedValue=*/false);
3230 
3231     SourceLocation SecColonLoc;
3232     ExprResult Step;
3233     // Parse optional step.
3234     if (Tok.is(tok::colon)) {
3235       // Parse ':'
3236       SecColonLoc = ConsumeToken();
3237       // Parse <step>
3238       Loc = Tok.getLocation();
3239       LHS = ParseCastExpression(AnyCastExpr);
3240       Step = Actions.CorrectDelayedTyposInExpr(
3241           ParseRHSOfBinaryExpression(LHS, prec::Conditional));
3242       Step = Actions.ActOnFinishFullExpr(Step.get(), Loc,
3243                                          /*DiscardedValue=*/false);
3244     }
3245 
3246     // Parse ',' or ')'
3247     if (Tok.isNot(tok::comma) && Tok.isNot(tok::r_paren))
3248       Diag(Tok, diag::err_omp_expected_punc_after_iterator);
3249     if (Tok.is(tok::comma))
3250       ConsumeToken();
3251 
3252     Sema::OMPIteratorData &D = Data.emplace_back();
3253     D.DeclIdent = II;
3254     D.DeclIdentLoc = IdLoc;
3255     D.Type = IteratorType;
3256     D.AssignLoc = AssignLoc;
3257     D.ColonLoc = ColonLoc;
3258     D.SecColonLoc = SecColonLoc;
3259     D.Range.Begin = Begin.get();
3260     D.Range.End = End.get();
3261     D.Range.Step = Step.get();
3262   }
3263 
3264   // Parse ')'.
3265   SourceLocation RLoc = Tok.getLocation();
3266   if (!T.consumeClose())
3267     RLoc = T.getCloseLocation();
3268 
3269   return Actions.ActOnOMPIteratorExpr(getCurScope(), IteratorKwLoc, LLoc, RLoc,
3270                                       Data);
3271 }
3272 
3273 /// Parses clauses with list.
3274 bool Parser::ParseOpenMPVarList(OpenMPDirectiveKind DKind,
3275                                 OpenMPClauseKind Kind,
3276                                 SmallVectorImpl<Expr *> &Vars,
3277                                 OpenMPVarListDataTy &Data) {
3278   UnqualifiedId UnqualifiedReductionId;
3279   bool InvalidReductionId = false;
3280   bool IsInvalidMapperModifier = false;
3281 
3282   // Parse '('.
3283   BalancedDelimiterTracker T(*this, tok::l_paren, tok::annot_pragma_openmp_end);
3284   if (T.expectAndConsume(diag::err_expected_lparen_after,
3285                          getOpenMPClauseName(Kind).data()))
3286     return true;
3287 
3288   bool HasIterator = false;
3289   bool NeedRParenForLinear = false;
3290   BalancedDelimiterTracker LinearT(*this, tok::l_paren,
3291                                   tok::annot_pragma_openmp_end);
3292   // Handle reduction-identifier for reduction clause.
3293   if (Kind == OMPC_reduction || Kind == OMPC_task_reduction ||
3294       Kind == OMPC_in_reduction) {
3295     Data.ExtraModifier = OMPC_REDUCTION_unknown;
3296     if (Kind == OMPC_reduction && getLangOpts().OpenMP >= 50 &&
3297         (Tok.is(tok::identifier) || Tok.is(tok::kw_default)) &&
3298         NextToken().is(tok::comma)) {
3299       // Parse optional reduction modifier.
3300       Data.ExtraModifier = getOpenMPSimpleClauseType(Kind, PP.getSpelling(Tok));
3301       Data.ExtraModifierLoc = Tok.getLocation();
3302       ConsumeToken();
3303       assert(Tok.is(tok::comma) && "Expected comma.");
3304       (void)ConsumeToken();
3305     }
3306     ColonProtectionRAIIObject ColonRAII(*this);
3307     if (getLangOpts().CPlusPlus)
3308       ParseOptionalCXXScopeSpecifier(Data.ReductionOrMapperIdScopeSpec,
3309                                      /*ObjectType=*/nullptr,
3310                                      /*ObjectHadErrors=*/false,
3311                                      /*EnteringContext=*/false);
3312     InvalidReductionId = ParseReductionId(
3313         *this, Data.ReductionOrMapperIdScopeSpec, UnqualifiedReductionId);
3314     if (InvalidReductionId) {
3315       SkipUntil(tok::colon, tok::r_paren, tok::annot_pragma_openmp_end,
3316                 StopBeforeMatch);
3317     }
3318     if (Tok.is(tok::colon))
3319       Data.ColonLoc = ConsumeToken();
3320     else
3321       Diag(Tok, diag::warn_pragma_expected_colon) << "reduction identifier";
3322     if (!InvalidReductionId)
3323       Data.ReductionOrMapperId =
3324           Actions.GetNameFromUnqualifiedId(UnqualifiedReductionId);
3325   } else if (Kind == OMPC_depend) {
3326     if (getLangOpts().OpenMP >= 50) {
3327       if (Tok.is(tok::identifier) && PP.getSpelling(Tok) == "iterator") {
3328         // Handle optional dependence modifier.
3329         // iterator(iterators-definition)
3330         // where iterators-definition is iterator-specifier [,
3331         // iterators-definition ]
3332         // where iterator-specifier is [ iterator-type ] identifier =
3333         // range-specification
3334         HasIterator = true;
3335         EnterScope(Scope::OpenMPDirectiveScope | Scope::DeclScope);
3336         ExprResult IteratorRes = ParseOpenMPIteratorsExpr();
3337         Data.DepModOrTailExpr = IteratorRes.get();
3338         // Parse ','
3339         ExpectAndConsume(tok::comma);
3340       }
3341     }
3342     // Handle dependency type for depend clause.
3343     ColonProtectionRAIIObject ColonRAII(*this);
3344     Data.ExtraModifier = getOpenMPSimpleClauseType(
3345         Kind, Tok.is(tok::identifier) ? PP.getSpelling(Tok) : "");
3346     Data.ExtraModifierLoc = Tok.getLocation();
3347     if (Data.ExtraModifier == OMPC_DEPEND_unknown) {
3348       SkipUntil(tok::colon, tok::r_paren, tok::annot_pragma_openmp_end,
3349                 StopBeforeMatch);
3350     } else {
3351       ConsumeToken();
3352       // Special processing for depend(source) clause.
3353       if (DKind == OMPD_ordered && Data.ExtraModifier == OMPC_DEPEND_source) {
3354         // Parse ')'.
3355         T.consumeClose();
3356         return false;
3357       }
3358     }
3359     if (Tok.is(tok::colon)) {
3360       Data.ColonLoc = ConsumeToken();
3361     } else {
3362       Diag(Tok, DKind == OMPD_ordered ? diag::warn_pragma_expected_colon_r_paren
3363                                       : diag::warn_pragma_expected_colon)
3364           << "dependency type";
3365     }
3366   } else if (Kind == OMPC_linear) {
3367     // Try to parse modifier if any.
3368     Data.ExtraModifier = OMPC_LINEAR_val;
3369     if (Tok.is(tok::identifier) && PP.LookAhead(0).is(tok::l_paren)) {
3370       Data.ExtraModifier = getOpenMPSimpleClauseType(Kind, PP.getSpelling(Tok));
3371       Data.ExtraModifierLoc = ConsumeToken();
3372       LinearT.consumeOpen();
3373       NeedRParenForLinear = true;
3374     }
3375   } else if (Kind == OMPC_lastprivate) {
3376     // Try to parse modifier if any.
3377     Data.ExtraModifier = OMPC_LASTPRIVATE_unknown;
3378     // Conditional modifier allowed only in OpenMP 5.0 and not supported in
3379     // distribute and taskloop based directives.
3380     if ((getLangOpts().OpenMP >= 50 && !isOpenMPDistributeDirective(DKind) &&
3381          !isOpenMPTaskLoopDirective(DKind)) &&
3382         Tok.is(tok::identifier) && PP.LookAhead(0).is(tok::colon)) {
3383       Data.ExtraModifier = getOpenMPSimpleClauseType(Kind, PP.getSpelling(Tok));
3384       Data.ExtraModifierLoc = Tok.getLocation();
3385       ConsumeToken();
3386       assert(Tok.is(tok::colon) && "Expected colon.");
3387       Data.ColonLoc = ConsumeToken();
3388     }
3389   } else if (Kind == OMPC_map) {
3390     // Handle map type for map clause.
3391     ColonProtectionRAIIObject ColonRAII(*this);
3392 
3393     // The first identifier may be a list item, a map-type or a
3394     // map-type-modifier. The map-type can also be delete which has the same
3395     // spelling of the C++ delete keyword.
3396     Data.ExtraModifier = OMPC_MAP_unknown;
3397     Data.ExtraModifierLoc = Tok.getLocation();
3398 
3399     // Check for presence of a colon in the map clause.
3400     TentativeParsingAction TPA(*this);
3401     bool ColonPresent = false;
3402     if (SkipUntil(tok::colon, tok::r_paren, tok::annot_pragma_openmp_end,
3403         StopBeforeMatch)) {
3404       if (Tok.is(tok::colon))
3405         ColonPresent = true;
3406     }
3407     TPA.Revert();
3408     // Only parse map-type-modifier[s] and map-type if a colon is present in
3409     // the map clause.
3410     if (ColonPresent) {
3411       IsInvalidMapperModifier = parseMapTypeModifiers(Data);
3412       if (!IsInvalidMapperModifier)
3413         parseMapType(*this, Data);
3414       else
3415         SkipUntil(tok::colon, tok::annot_pragma_openmp_end, StopBeforeMatch);
3416     }
3417     if (Data.ExtraModifier == OMPC_MAP_unknown) {
3418       Data.ExtraModifier = OMPC_MAP_tofrom;
3419       Data.IsMapTypeImplicit = true;
3420     }
3421 
3422     if (Tok.is(tok::colon))
3423       Data.ColonLoc = ConsumeToken();
3424   } else if (Kind == OMPC_to || Kind == OMPC_from) {
3425     if (Tok.is(tok::identifier)) {
3426       bool IsMapperModifier = false;
3427       if (Kind == OMPC_to) {
3428         auto Modifier = static_cast<OpenMPToModifierKind>(
3429             getOpenMPSimpleClauseType(Kind, PP.getSpelling(Tok)));
3430         if (Modifier == OMPC_TO_MODIFIER_mapper)
3431           IsMapperModifier = true;
3432       } else {
3433         auto Modifier = static_cast<OpenMPFromModifierKind>(
3434             getOpenMPSimpleClauseType(Kind, PP.getSpelling(Tok)));
3435         if (Modifier == OMPC_FROM_MODIFIER_mapper)
3436           IsMapperModifier = true;
3437       }
3438       if (IsMapperModifier) {
3439         // Parse the mapper modifier.
3440         ConsumeToken();
3441         IsInvalidMapperModifier = parseMapperModifier(Data);
3442         if (Tok.isNot(tok::colon)) {
3443           if (!IsInvalidMapperModifier)
3444             Diag(Tok, diag::warn_pragma_expected_colon) << ")";
3445           SkipUntil(tok::colon, tok::r_paren, tok::annot_pragma_openmp_end,
3446                     StopBeforeMatch);
3447         }
3448         // Consume ':'.
3449         if (Tok.is(tok::colon))
3450           ConsumeToken();
3451       }
3452     }
3453   } else if (Kind == OMPC_allocate ||
3454              (Kind == OMPC_affinity && Tok.is(tok::identifier) &&
3455               PP.getSpelling(Tok) == "iterator")) {
3456     // Handle optional allocator expression followed by colon delimiter.
3457     ColonProtectionRAIIObject ColonRAII(*this);
3458     TentativeParsingAction TPA(*this);
3459     // OpenMP 5.0, 2.10.1, task Construct.
3460     // where aff-modifier is one of the following:
3461     // iterator(iterators-definition)
3462     ExprResult Tail;
3463     if (Kind == OMPC_allocate) {
3464       Tail = ParseAssignmentExpression();
3465     } else {
3466       HasIterator = true;
3467       EnterScope(Scope::OpenMPDirectiveScope | Scope::DeclScope);
3468       Tail = ParseOpenMPIteratorsExpr();
3469     }
3470     Tail = Actions.CorrectDelayedTyposInExpr(Tail);
3471     Tail = Actions.ActOnFinishFullExpr(Tail.get(), T.getOpenLocation(),
3472                                        /*DiscardedValue=*/false);
3473     if (Tail.isUsable()) {
3474       if (Tok.is(tok::colon)) {
3475         Data.DepModOrTailExpr = Tail.get();
3476         Data.ColonLoc = ConsumeToken();
3477         TPA.Commit();
3478       } else {
3479         // Colon not found, parse only list of variables.
3480         TPA.Revert();
3481       }
3482     } else {
3483       // Parsing was unsuccessfull, revert and skip to the end of clause or
3484       // directive.
3485       TPA.Revert();
3486       SkipUntil(tok::comma, tok::r_paren, tok::annot_pragma_openmp_end,
3487                 StopBeforeMatch);
3488     }
3489   }
3490 
3491   bool IsComma =
3492       (Kind != OMPC_reduction && Kind != OMPC_task_reduction &&
3493        Kind != OMPC_in_reduction && Kind != OMPC_depend && Kind != OMPC_map) ||
3494       (Kind == OMPC_reduction && !InvalidReductionId) ||
3495       (Kind == OMPC_map && Data.ExtraModifier != OMPC_MAP_unknown) ||
3496       (Kind == OMPC_depend && Data.ExtraModifier != OMPC_DEPEND_unknown);
3497   const bool MayHaveTail = (Kind == OMPC_linear || Kind == OMPC_aligned);
3498   while (IsComma || (Tok.isNot(tok::r_paren) && Tok.isNot(tok::colon) &&
3499                      Tok.isNot(tok::annot_pragma_openmp_end))) {
3500     ParseScope OMPListScope(this, Scope::OpenMPDirectiveScope);
3501     ColonProtectionRAIIObject ColonRAII(*this, MayHaveTail);
3502     // Parse variable
3503     ExprResult VarExpr =
3504         Actions.CorrectDelayedTyposInExpr(ParseAssignmentExpression());
3505     if (VarExpr.isUsable()) {
3506       Vars.push_back(VarExpr.get());
3507     } else {
3508       SkipUntil(tok::comma, tok::r_paren, tok::annot_pragma_openmp_end,
3509                 StopBeforeMatch);
3510     }
3511     // Skip ',' if any
3512     IsComma = Tok.is(tok::comma);
3513     if (IsComma)
3514       ConsumeToken();
3515     else if (Tok.isNot(tok::r_paren) &&
3516              Tok.isNot(tok::annot_pragma_openmp_end) &&
3517              (!MayHaveTail || Tok.isNot(tok::colon)))
3518       Diag(Tok, diag::err_omp_expected_punc)
3519           << ((Kind == OMPC_flush) ? getOpenMPDirectiveName(OMPD_flush)
3520                                    : getOpenMPClauseName(Kind))
3521           << (Kind == OMPC_flush);
3522   }
3523 
3524   // Parse ')' for linear clause with modifier.
3525   if (NeedRParenForLinear)
3526     LinearT.consumeClose();
3527 
3528   // Parse ':' linear-step (or ':' alignment).
3529   const bool MustHaveTail = MayHaveTail && Tok.is(tok::colon);
3530   if (MustHaveTail) {
3531     Data.ColonLoc = Tok.getLocation();
3532     SourceLocation ELoc = ConsumeToken();
3533     ExprResult Tail = ParseAssignmentExpression();
3534     Tail =
3535         Actions.ActOnFinishFullExpr(Tail.get(), ELoc, /*DiscardedValue*/ false);
3536     if (Tail.isUsable())
3537       Data.DepModOrTailExpr = Tail.get();
3538     else
3539       SkipUntil(tok::comma, tok::r_paren, tok::annot_pragma_openmp_end,
3540                 StopBeforeMatch);
3541   }
3542 
3543   // Parse ')'.
3544   Data.RLoc = Tok.getLocation();
3545   if (!T.consumeClose())
3546     Data.RLoc = T.getCloseLocation();
3547   // Exit from scope when the iterator is used in depend clause.
3548   if (HasIterator)
3549     ExitScope();
3550   return (Kind != OMPC_depend && Kind != OMPC_map && Vars.empty()) ||
3551          (MustHaveTail && !Data.DepModOrTailExpr) || InvalidReductionId ||
3552          IsInvalidMapperModifier;
3553 }
3554 
3555 /// Parsing of OpenMP clause 'private', 'firstprivate', 'lastprivate',
3556 /// 'shared', 'copyin', 'copyprivate', 'flush', 'reduction', 'task_reduction',
3557 /// 'in_reduction', 'nontemporal', 'exclusive' or 'inclusive'.
3558 ///
3559 ///    private-clause:
3560 ///       'private' '(' list ')'
3561 ///    firstprivate-clause:
3562 ///       'firstprivate' '(' list ')'
3563 ///    lastprivate-clause:
3564 ///       'lastprivate' '(' list ')'
3565 ///    shared-clause:
3566 ///       'shared' '(' list ')'
3567 ///    linear-clause:
3568 ///       'linear' '(' linear-list [ ':' linear-step ] ')'
3569 ///    aligned-clause:
3570 ///       'aligned' '(' list [ ':' alignment ] ')'
3571 ///    reduction-clause:
3572 ///       'reduction' '(' [ modifier ',' ] reduction-identifier ':' list ')'
3573 ///    task_reduction-clause:
3574 ///       'task_reduction' '(' reduction-identifier ':' list ')'
3575 ///    in_reduction-clause:
3576 ///       'in_reduction' '(' reduction-identifier ':' list ')'
3577 ///    copyprivate-clause:
3578 ///       'copyprivate' '(' list ')'
3579 ///    flush-clause:
3580 ///       'flush' '(' list ')'
3581 ///    depend-clause:
3582 ///       'depend' '(' in | out | inout : list | source ')'
3583 ///    map-clause:
3584 ///       'map' '(' [ [ always [,] ] [ close [,] ]
3585 ///          [ mapper '(' mapper-identifier ')' [,] ]
3586 ///          to | from | tofrom | alloc | release | delete ':' ] list ')';
3587 ///    to-clause:
3588 ///       'to' '(' [ mapper '(' mapper-identifier ')' ':' ] list ')'
3589 ///    from-clause:
3590 ///       'from' '(' [ mapper '(' mapper-identifier ')' ':' ] list ')'
3591 ///    use_device_ptr-clause:
3592 ///       'use_device_ptr' '(' list ')'
3593 ///    use_device_addr-clause:
3594 ///       'use_device_addr' '(' list ')'
3595 ///    is_device_ptr-clause:
3596 ///       'is_device_ptr' '(' list ')'
3597 ///    allocate-clause:
3598 ///       'allocate' '(' [ allocator ':' ] list ')'
3599 ///    nontemporal-clause:
3600 ///       'nontemporal' '(' list ')'
3601 ///    inclusive-clause:
3602 ///       'inclusive' '(' list ')'
3603 ///    exclusive-clause:
3604 ///       'exclusive' '(' list ')'
3605 ///
3606 /// For 'linear' clause linear-list may have the following forms:
3607 ///  list
3608 ///  modifier(list)
3609 /// where modifier is 'val' (C) or 'ref', 'val' or 'uval'(C++).
3610 OMPClause *Parser::ParseOpenMPVarListClause(OpenMPDirectiveKind DKind,
3611                                             OpenMPClauseKind Kind,
3612                                             bool ParseOnly) {
3613   SourceLocation Loc = Tok.getLocation();
3614   SourceLocation LOpen = ConsumeToken();
3615   SmallVector<Expr *, 4> Vars;
3616   OpenMPVarListDataTy Data;
3617 
3618   if (ParseOpenMPVarList(DKind, Kind, Vars, Data))
3619     return nullptr;
3620 
3621   if (ParseOnly)
3622     return nullptr;
3623   OMPVarListLocTy Locs(Loc, LOpen, Data.RLoc);
3624   return Actions.ActOnOpenMPVarListClause(
3625       Kind, Vars, Data.DepModOrTailExpr, Locs, Data.ColonLoc,
3626       Data.ReductionOrMapperIdScopeSpec, Data.ReductionOrMapperId,
3627       Data.ExtraModifier, Data.MapTypeModifiers, Data.MapTypeModifiersLoc,
3628       Data.IsMapTypeImplicit, Data.ExtraModifierLoc);
3629 }
3630 
3631