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