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1  //===--- Expr.cpp - Expression AST Node Implementation --------------------===//
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  //
10  // This file implements the Expr class and subclasses.
11  //
12  //===----------------------------------------------------------------------===//
13  
14  #include "clang/AST/APValue.h"
15  #include "clang/AST/ASTContext.h"
16  #include "clang/AST/Attr.h"
17  #include "clang/AST/DeclCXX.h"
18  #include "clang/AST/DeclObjC.h"
19  #include "clang/AST/DeclTemplate.h"
20  #include "clang/AST/EvaluatedExprVisitor.h"
21  #include "clang/AST/Expr.h"
22  #include "clang/AST/ExprCXX.h"
23  #include "clang/AST/Mangle.h"
24  #include "clang/AST/RecordLayout.h"
25  #include "clang/AST/StmtVisitor.h"
26  #include "clang/Basic/Builtins.h"
27  #include "clang/Basic/CharInfo.h"
28  #include "clang/Basic/SourceManager.h"
29  #include "clang/Basic/TargetInfo.h"
30  #include "clang/Lex/Lexer.h"
31  #include "clang/Lex/LiteralSupport.h"
32  #include "clang/Sema/SemaDiagnostic.h"
33  #include "llvm/Support/ErrorHandling.h"
34  #include "llvm/Support/raw_ostream.h"
35  #include <algorithm>
36  #include <cstring>
37  using namespace clang;
38  
getBestDynamicClassType() const39  const CXXRecordDecl *Expr::getBestDynamicClassType() const {
40    const Expr *E = ignoreParenBaseCasts();
41  
42    QualType DerivedType = E->getType();
43    if (const PointerType *PTy = DerivedType->getAs<PointerType>())
44      DerivedType = PTy->getPointeeType();
45  
46    if (DerivedType->isDependentType())
47      return nullptr;
48  
49    const RecordType *Ty = DerivedType->castAs<RecordType>();
50    Decl *D = Ty->getDecl();
51    return cast<CXXRecordDecl>(D);
52  }
53  
skipRValueSubobjectAdjustments(SmallVectorImpl<const Expr * > & CommaLHSs,SmallVectorImpl<SubobjectAdjustment> & Adjustments) const54  const Expr *Expr::skipRValueSubobjectAdjustments(
55      SmallVectorImpl<const Expr *> &CommaLHSs,
56      SmallVectorImpl<SubobjectAdjustment> &Adjustments) const {
57    const Expr *E = this;
58    while (true) {
59      E = E->IgnoreParens();
60  
61      if (const CastExpr *CE = dyn_cast<CastExpr>(E)) {
62        if ((CE->getCastKind() == CK_DerivedToBase ||
63             CE->getCastKind() == CK_UncheckedDerivedToBase) &&
64            E->getType()->isRecordType()) {
65          E = CE->getSubExpr();
66          CXXRecordDecl *Derived
67            = cast<CXXRecordDecl>(E->getType()->getAs<RecordType>()->getDecl());
68          Adjustments.push_back(SubobjectAdjustment(CE, Derived));
69          continue;
70        }
71  
72        if (CE->getCastKind() == CK_NoOp) {
73          E = CE->getSubExpr();
74          continue;
75        }
76      } else if (const MemberExpr *ME = dyn_cast<MemberExpr>(E)) {
77        if (!ME->isArrow()) {
78          assert(ME->getBase()->getType()->isRecordType());
79          if (FieldDecl *Field = dyn_cast<FieldDecl>(ME->getMemberDecl())) {
80            if (!Field->isBitField() && !Field->getType()->isReferenceType()) {
81              E = ME->getBase();
82              Adjustments.push_back(SubobjectAdjustment(Field));
83              continue;
84            }
85          }
86        }
87      } else if (const BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) {
88        if (BO->isPtrMemOp()) {
89          assert(BO->getRHS()->isRValue());
90          E = BO->getLHS();
91          const MemberPointerType *MPT =
92            BO->getRHS()->getType()->getAs<MemberPointerType>();
93          Adjustments.push_back(SubobjectAdjustment(MPT, BO->getRHS()));
94          continue;
95        } else if (BO->getOpcode() == BO_Comma) {
96          CommaLHSs.push_back(BO->getLHS());
97          E = BO->getRHS();
98          continue;
99        }
100      }
101  
102      // Nothing changed.
103      break;
104    }
105    return E;
106  }
107  
108  /// isKnownToHaveBooleanValue - Return true if this is an integer expression
109  /// that is known to return 0 or 1.  This happens for _Bool/bool expressions
110  /// but also int expressions which are produced by things like comparisons in
111  /// C.
isKnownToHaveBooleanValue() const112  bool Expr::isKnownToHaveBooleanValue() const {
113    const Expr *E = IgnoreParens();
114  
115    // If this value has _Bool type, it is obvious 0/1.
116    if (E->getType()->isBooleanType()) return true;
117    // If this is a non-scalar-integer type, we don't care enough to try.
118    if (!E->getType()->isIntegralOrEnumerationType()) return false;
119  
120    if (const UnaryOperator *UO = dyn_cast<UnaryOperator>(E)) {
121      switch (UO->getOpcode()) {
122      case UO_Plus:
123        return UO->getSubExpr()->isKnownToHaveBooleanValue();
124      case UO_LNot:
125        return true;
126      default:
127        return false;
128      }
129    }
130  
131    // Only look through implicit casts.  If the user writes
132    // '(int) (a && b)' treat it as an arbitrary int.
133    if (const ImplicitCastExpr *CE = dyn_cast<ImplicitCastExpr>(E))
134      return CE->getSubExpr()->isKnownToHaveBooleanValue();
135  
136    if (const BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) {
137      switch (BO->getOpcode()) {
138      default: return false;
139      case BO_LT:   // Relational operators.
140      case BO_GT:
141      case BO_LE:
142      case BO_GE:
143      case BO_EQ:   // Equality operators.
144      case BO_NE:
145      case BO_LAnd: // AND operator.
146      case BO_LOr:  // Logical OR operator.
147        return true;
148  
149      case BO_And:  // Bitwise AND operator.
150      case BO_Xor:  // Bitwise XOR operator.
151      case BO_Or:   // Bitwise OR operator.
152        // Handle things like (x==2)|(y==12).
153        return BO->getLHS()->isKnownToHaveBooleanValue() &&
154               BO->getRHS()->isKnownToHaveBooleanValue();
155  
156      case BO_Comma:
157      case BO_Assign:
158        return BO->getRHS()->isKnownToHaveBooleanValue();
159      }
160    }
161  
162    if (const ConditionalOperator *CO = dyn_cast<ConditionalOperator>(E))
163      return CO->getTrueExpr()->isKnownToHaveBooleanValue() &&
164             CO->getFalseExpr()->isKnownToHaveBooleanValue();
165  
166    return false;
167  }
168  
169  // Amusing macro metaprogramming hack: check whether a class provides
170  // a more specific implementation of getExprLoc().
171  //
172  // See also Stmt.cpp:{getLocStart(),getLocEnd()}.
173  namespace {
174    /// This implementation is used when a class provides a custom
175    /// implementation of getExprLoc.
176    template <class E, class T>
getExprLocImpl(const Expr * expr,SourceLocation (T::* v)()const)177    SourceLocation getExprLocImpl(const Expr *expr,
178                                  SourceLocation (T::*v)() const) {
179      return static_cast<const E*>(expr)->getExprLoc();
180    }
181  
182    /// This implementation is used when a class doesn't provide
183    /// a custom implementation of getExprLoc.  Overload resolution
184    /// should pick it over the implementation above because it's
185    /// more specialized according to function template partial ordering.
186    template <class E>
getExprLocImpl(const Expr * expr,SourceLocation (Expr::* v)()const)187    SourceLocation getExprLocImpl(const Expr *expr,
188                                  SourceLocation (Expr::*v)() const) {
189      return static_cast<const E*>(expr)->getLocStart();
190    }
191  }
192  
getExprLoc() const193  SourceLocation Expr::getExprLoc() const {
194    switch (getStmtClass()) {
195    case Stmt::NoStmtClass: llvm_unreachable("statement without class");
196  #define ABSTRACT_STMT(type)
197  #define STMT(type, base) \
198    case Stmt::type##Class: break;
199  #define EXPR(type, base) \
200    case Stmt::type##Class: return getExprLocImpl<type>(this, &type::getExprLoc);
201  #include "clang/AST/StmtNodes.inc"
202    }
203    llvm_unreachable("unknown expression kind");
204  }
205  
206  //===----------------------------------------------------------------------===//
207  // Primary Expressions.
208  //===----------------------------------------------------------------------===//
209  
210  /// \brief Compute the type-, value-, and instantiation-dependence of a
211  /// declaration reference
212  /// based on the declaration being referenced.
computeDeclRefDependence(const ASTContext & Ctx,NamedDecl * D,QualType T,bool & TypeDependent,bool & ValueDependent,bool & InstantiationDependent)213  static void computeDeclRefDependence(const ASTContext &Ctx, NamedDecl *D,
214                                       QualType T, bool &TypeDependent,
215                                       bool &ValueDependent,
216                                       bool &InstantiationDependent) {
217    TypeDependent = false;
218    ValueDependent = false;
219    InstantiationDependent = false;
220  
221    // (TD) C++ [temp.dep.expr]p3:
222    //   An id-expression is type-dependent if it contains:
223    //
224    // and
225    //
226    // (VD) C++ [temp.dep.constexpr]p2:
227    //  An identifier is value-dependent if it is:
228  
229    //  (TD)  - an identifier that was declared with dependent type
230    //  (VD)  - a name declared with a dependent type,
231    if (T->isDependentType()) {
232      TypeDependent = true;
233      ValueDependent = true;
234      InstantiationDependent = true;
235      return;
236    } else if (T->isInstantiationDependentType()) {
237      InstantiationDependent = true;
238    }
239  
240    //  (TD)  - a conversion-function-id that specifies a dependent type
241    if (D->getDeclName().getNameKind()
242                                  == DeclarationName::CXXConversionFunctionName) {
243      QualType T = D->getDeclName().getCXXNameType();
244      if (T->isDependentType()) {
245        TypeDependent = true;
246        ValueDependent = true;
247        InstantiationDependent = true;
248        return;
249      }
250  
251      if (T->isInstantiationDependentType())
252        InstantiationDependent = true;
253    }
254  
255    //  (VD)  - the name of a non-type template parameter,
256    if (isa<NonTypeTemplateParmDecl>(D)) {
257      ValueDependent = true;
258      InstantiationDependent = true;
259      return;
260    }
261  
262    //  (VD) - a constant with integral or enumeration type and is
263    //         initialized with an expression that is value-dependent.
264    //  (VD) - a constant with literal type and is initialized with an
265    //         expression that is value-dependent [C++11].
266    //  (VD) - FIXME: Missing from the standard:
267    //       -  an entity with reference type and is initialized with an
268    //          expression that is value-dependent [C++11]
269    if (VarDecl *Var = dyn_cast<VarDecl>(D)) {
270      if ((Ctx.getLangOpts().CPlusPlus11 ?
271             Var->getType()->isLiteralType(Ctx) :
272             Var->getType()->isIntegralOrEnumerationType()) &&
273          (Var->getType().isConstQualified() ||
274           Var->getType()->isReferenceType())) {
275        if (const Expr *Init = Var->getAnyInitializer())
276          if (Init->isValueDependent()) {
277            ValueDependent = true;
278            InstantiationDependent = true;
279          }
280      }
281  
282      // (VD) - FIXME: Missing from the standard:
283      //      -  a member function or a static data member of the current
284      //         instantiation
285      if (Var->isStaticDataMember() &&
286          Var->getDeclContext()->isDependentContext()) {
287        ValueDependent = true;
288        InstantiationDependent = true;
289        TypeSourceInfo *TInfo = Var->getFirstDecl()->getTypeSourceInfo();
290        if (TInfo->getType()->isIncompleteArrayType())
291          TypeDependent = true;
292      }
293  
294      return;
295    }
296  
297    // (VD) - FIXME: Missing from the standard:
298    //      -  a member function or a static data member of the current
299    //         instantiation
300    if (isa<CXXMethodDecl>(D) && D->getDeclContext()->isDependentContext()) {
301      ValueDependent = true;
302      InstantiationDependent = true;
303    }
304  }
305  
computeDependence(const ASTContext & Ctx)306  void DeclRefExpr::computeDependence(const ASTContext &Ctx) {
307    bool TypeDependent = false;
308    bool ValueDependent = false;
309    bool InstantiationDependent = false;
310    computeDeclRefDependence(Ctx, getDecl(), getType(), TypeDependent,
311                             ValueDependent, InstantiationDependent);
312  
313    ExprBits.TypeDependent |= TypeDependent;
314    ExprBits.ValueDependent |= ValueDependent;
315    ExprBits.InstantiationDependent |= InstantiationDependent;
316  
317    // Is the declaration a parameter pack?
318    if (getDecl()->isParameterPack())
319      ExprBits.ContainsUnexpandedParameterPack = true;
320  }
321  
DeclRefExpr(const ASTContext & Ctx,NestedNameSpecifierLoc QualifierLoc,SourceLocation TemplateKWLoc,ValueDecl * D,bool RefersToEnclosingVariableOrCapture,const DeclarationNameInfo & NameInfo,NamedDecl * FoundD,const TemplateArgumentListInfo * TemplateArgs,QualType T,ExprValueKind VK)322  DeclRefExpr::DeclRefExpr(const ASTContext &Ctx,
323                           NestedNameSpecifierLoc QualifierLoc,
324                           SourceLocation TemplateKWLoc,
325                           ValueDecl *D, bool RefersToEnclosingVariableOrCapture,
326                           const DeclarationNameInfo &NameInfo,
327                           NamedDecl *FoundD,
328                           const TemplateArgumentListInfo *TemplateArgs,
329                           QualType T, ExprValueKind VK)
330    : Expr(DeclRefExprClass, T, VK, OK_Ordinary, false, false, false, false),
331      D(D), Loc(NameInfo.getLoc()), DNLoc(NameInfo.getInfo()) {
332    DeclRefExprBits.HasQualifier = QualifierLoc ? 1 : 0;
333    if (QualifierLoc) {
334      getInternalQualifierLoc() = QualifierLoc;
335      auto *NNS = QualifierLoc.getNestedNameSpecifier();
336      if (NNS->isInstantiationDependent())
337        ExprBits.InstantiationDependent = true;
338      if (NNS->containsUnexpandedParameterPack())
339        ExprBits.ContainsUnexpandedParameterPack = true;
340    }
341    DeclRefExprBits.HasFoundDecl = FoundD ? 1 : 0;
342    if (FoundD)
343      getInternalFoundDecl() = FoundD;
344    DeclRefExprBits.HasTemplateKWAndArgsInfo
345      = (TemplateArgs || TemplateKWLoc.isValid()) ? 1 : 0;
346    DeclRefExprBits.RefersToEnclosingVariableOrCapture =
347        RefersToEnclosingVariableOrCapture;
348    if (TemplateArgs) {
349      bool Dependent = false;
350      bool InstantiationDependent = false;
351      bool ContainsUnexpandedParameterPack = false;
352      getTemplateKWAndArgsInfo()->initializeFrom(TemplateKWLoc, *TemplateArgs,
353                                                 Dependent,
354                                                 InstantiationDependent,
355                                                 ContainsUnexpandedParameterPack);
356      assert(!Dependent && "built a DeclRefExpr with dependent template args");
357      ExprBits.InstantiationDependent |= InstantiationDependent;
358      ExprBits.ContainsUnexpandedParameterPack |= ContainsUnexpandedParameterPack;
359    } else if (TemplateKWLoc.isValid()) {
360      getTemplateKWAndArgsInfo()->initializeFrom(TemplateKWLoc);
361    }
362    DeclRefExprBits.HadMultipleCandidates = 0;
363  
364    computeDependence(Ctx);
365  }
366  
Create(const ASTContext & Context,NestedNameSpecifierLoc QualifierLoc,SourceLocation TemplateKWLoc,ValueDecl * D,bool RefersToEnclosingVariableOrCapture,SourceLocation NameLoc,QualType T,ExprValueKind VK,NamedDecl * FoundD,const TemplateArgumentListInfo * TemplateArgs)367  DeclRefExpr *DeclRefExpr::Create(const ASTContext &Context,
368                                   NestedNameSpecifierLoc QualifierLoc,
369                                   SourceLocation TemplateKWLoc,
370                                   ValueDecl *D,
371                                   bool RefersToEnclosingVariableOrCapture,
372                                   SourceLocation NameLoc,
373                                   QualType T,
374                                   ExprValueKind VK,
375                                   NamedDecl *FoundD,
376                                   const TemplateArgumentListInfo *TemplateArgs) {
377    return Create(Context, QualifierLoc, TemplateKWLoc, D,
378                  RefersToEnclosingVariableOrCapture,
379                  DeclarationNameInfo(D->getDeclName(), NameLoc),
380                  T, VK, FoundD, TemplateArgs);
381  }
382  
Create(const ASTContext & Context,NestedNameSpecifierLoc QualifierLoc,SourceLocation TemplateKWLoc,ValueDecl * D,bool RefersToEnclosingVariableOrCapture,const DeclarationNameInfo & NameInfo,QualType T,ExprValueKind VK,NamedDecl * FoundD,const TemplateArgumentListInfo * TemplateArgs)383  DeclRefExpr *DeclRefExpr::Create(const ASTContext &Context,
384                                   NestedNameSpecifierLoc QualifierLoc,
385                                   SourceLocation TemplateKWLoc,
386                                   ValueDecl *D,
387                                   bool RefersToEnclosingVariableOrCapture,
388                                   const DeclarationNameInfo &NameInfo,
389                                   QualType T,
390                                   ExprValueKind VK,
391                                   NamedDecl *FoundD,
392                                   const TemplateArgumentListInfo *TemplateArgs) {
393    // Filter out cases where the found Decl is the same as the value refenenced.
394    if (D == FoundD)
395      FoundD = nullptr;
396  
397    std::size_t Size = sizeof(DeclRefExpr);
398    if (QualifierLoc)
399      Size += sizeof(NestedNameSpecifierLoc);
400    if (FoundD)
401      Size += sizeof(NamedDecl *);
402    if (TemplateArgs) {
403      Size = llvm::RoundUpToAlignment(Size,
404                                      llvm::alignOf<ASTTemplateKWAndArgsInfo>());
405      Size += ASTTemplateKWAndArgsInfo::sizeFor(TemplateArgs->size());
406    } else if (TemplateKWLoc.isValid()) {
407      Size = llvm::RoundUpToAlignment(Size,
408                                      llvm::alignOf<ASTTemplateKWAndArgsInfo>());
409      Size += ASTTemplateKWAndArgsInfo::sizeFor(0);
410    }
411  
412    void *Mem = Context.Allocate(Size, llvm::alignOf<DeclRefExpr>());
413    return new (Mem) DeclRefExpr(Context, QualifierLoc, TemplateKWLoc, D,
414                                 RefersToEnclosingVariableOrCapture,
415                                 NameInfo, FoundD, TemplateArgs, T, VK);
416  }
417  
CreateEmpty(const ASTContext & Context,bool HasQualifier,bool HasFoundDecl,bool HasTemplateKWAndArgsInfo,unsigned NumTemplateArgs)418  DeclRefExpr *DeclRefExpr::CreateEmpty(const ASTContext &Context,
419                                        bool HasQualifier,
420                                        bool HasFoundDecl,
421                                        bool HasTemplateKWAndArgsInfo,
422                                        unsigned NumTemplateArgs) {
423    std::size_t Size = sizeof(DeclRefExpr);
424    if (HasQualifier)
425      Size += sizeof(NestedNameSpecifierLoc);
426    if (HasFoundDecl)
427      Size += sizeof(NamedDecl *);
428    if (HasTemplateKWAndArgsInfo) {
429      Size = llvm::RoundUpToAlignment(Size,
430                                      llvm::alignOf<ASTTemplateKWAndArgsInfo>());
431      Size += ASTTemplateKWAndArgsInfo::sizeFor(NumTemplateArgs);
432    }
433  
434    void *Mem = Context.Allocate(Size, llvm::alignOf<DeclRefExpr>());
435    return new (Mem) DeclRefExpr(EmptyShell());
436  }
437  
getLocStart() const438  SourceLocation DeclRefExpr::getLocStart() const {
439    if (hasQualifier())
440      return getQualifierLoc().getBeginLoc();
441    return getNameInfo().getLocStart();
442  }
getLocEnd() const443  SourceLocation DeclRefExpr::getLocEnd() const {
444    if (hasExplicitTemplateArgs())
445      return getRAngleLoc();
446    return getNameInfo().getLocEnd();
447  }
448  
PredefinedExpr(SourceLocation L,QualType FNTy,IdentType IT,StringLiteral * SL)449  PredefinedExpr::PredefinedExpr(SourceLocation L, QualType FNTy, IdentType IT,
450                                 StringLiteral *SL)
451      : Expr(PredefinedExprClass, FNTy, VK_LValue, OK_Ordinary,
452             FNTy->isDependentType(), FNTy->isDependentType(),
453             FNTy->isInstantiationDependentType(),
454             /*ContainsUnexpandedParameterPack=*/false),
455        Loc(L), Type(IT), FnName(SL) {}
456  
getFunctionName()457  StringLiteral *PredefinedExpr::getFunctionName() {
458    return cast_or_null<StringLiteral>(FnName);
459  }
460  
getIdentTypeName(PredefinedExpr::IdentType IT)461  StringRef PredefinedExpr::getIdentTypeName(PredefinedExpr::IdentType IT) {
462    switch (IT) {
463    case Func:
464      return "__func__";
465    case Function:
466      return "__FUNCTION__";
467    case FuncDName:
468      return "__FUNCDNAME__";
469    case LFunction:
470      return "L__FUNCTION__";
471    case PrettyFunction:
472      return "__PRETTY_FUNCTION__";
473    case FuncSig:
474      return "__FUNCSIG__";
475    case PrettyFunctionNoVirtual:
476      break;
477    }
478    llvm_unreachable("Unknown ident type for PredefinedExpr");
479  }
480  
481  // FIXME: Maybe this should use DeclPrinter with a special "print predefined
482  // expr" policy instead.
ComputeName(IdentType IT,const Decl * CurrentDecl)483  std::string PredefinedExpr::ComputeName(IdentType IT, const Decl *CurrentDecl) {
484    ASTContext &Context = CurrentDecl->getASTContext();
485  
486    if (IT == PredefinedExpr::FuncDName) {
487      if (const NamedDecl *ND = dyn_cast<NamedDecl>(CurrentDecl)) {
488        std::unique_ptr<MangleContext> MC;
489        MC.reset(Context.createMangleContext());
490  
491        if (MC->shouldMangleDeclName(ND)) {
492          SmallString<256> Buffer;
493          llvm::raw_svector_ostream Out(Buffer);
494          if (const CXXConstructorDecl *CD = dyn_cast<CXXConstructorDecl>(ND))
495            MC->mangleCXXCtor(CD, Ctor_Base, Out);
496          else if (const CXXDestructorDecl *DD = dyn_cast<CXXDestructorDecl>(ND))
497            MC->mangleCXXDtor(DD, Dtor_Base, Out);
498          else
499            MC->mangleName(ND, Out);
500  
501          if (!Buffer.empty() && Buffer.front() == '\01')
502            return Buffer.substr(1);
503          return Buffer.str();
504        } else
505          return ND->getIdentifier()->getName();
506      }
507      return "";
508    }
509    if (auto *BD = dyn_cast<BlockDecl>(CurrentDecl)) {
510      std::unique_ptr<MangleContext> MC;
511      MC.reset(Context.createMangleContext());
512      SmallString<256> Buffer;
513      llvm::raw_svector_ostream Out(Buffer);
514      auto DC = CurrentDecl->getDeclContext();
515      if (DC->isFileContext())
516        MC->mangleGlobalBlock(BD, /*ID*/ nullptr, Out);
517      else if (const auto *CD = dyn_cast<CXXConstructorDecl>(DC))
518        MC->mangleCtorBlock(CD, /*CT*/ Ctor_Complete, BD, Out);
519      else if (const auto *DD = dyn_cast<CXXDestructorDecl>(DC))
520        MC->mangleDtorBlock(DD, /*DT*/ Dtor_Complete, BD, Out);
521      else
522        MC->mangleBlock(DC, BD, Out);
523      return Out.str();
524    }
525    if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(CurrentDecl)) {
526      if (IT != PrettyFunction && IT != PrettyFunctionNoVirtual && IT != FuncSig)
527        return FD->getNameAsString();
528  
529      SmallString<256> Name;
530      llvm::raw_svector_ostream Out(Name);
531  
532      if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
533        if (MD->isVirtual() && IT != PrettyFunctionNoVirtual)
534          Out << "virtual ";
535        if (MD->isStatic())
536          Out << "static ";
537      }
538  
539      PrintingPolicy Policy(Context.getLangOpts());
540      std::string Proto;
541      llvm::raw_string_ostream POut(Proto);
542  
543      const FunctionDecl *Decl = FD;
544      if (const FunctionDecl* Pattern = FD->getTemplateInstantiationPattern())
545        Decl = Pattern;
546      const FunctionType *AFT = Decl->getType()->getAs<FunctionType>();
547      const FunctionProtoType *FT = nullptr;
548      if (FD->hasWrittenPrototype())
549        FT = dyn_cast<FunctionProtoType>(AFT);
550  
551      if (IT == FuncSig) {
552        switch (FT->getCallConv()) {
553        case CC_C: POut << "__cdecl "; break;
554        case CC_X86StdCall: POut << "__stdcall "; break;
555        case CC_X86FastCall: POut << "__fastcall "; break;
556        case CC_X86ThisCall: POut << "__thiscall "; break;
557        case CC_X86VectorCall: POut << "__vectorcall "; break;
558        // Only bother printing the conventions that MSVC knows about.
559        default: break;
560        }
561      }
562  
563      FD->printQualifiedName(POut, Policy);
564  
565      POut << "(";
566      if (FT) {
567        for (unsigned i = 0, e = Decl->getNumParams(); i != e; ++i) {
568          if (i) POut << ", ";
569          POut << Decl->getParamDecl(i)->getType().stream(Policy);
570        }
571  
572        if (FT->isVariadic()) {
573          if (FD->getNumParams()) POut << ", ";
574          POut << "...";
575        }
576      }
577      POut << ")";
578  
579      if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
580        const FunctionType *FT = MD->getType()->castAs<FunctionType>();
581        if (FT->isConst())
582          POut << " const";
583        if (FT->isVolatile())
584          POut << " volatile";
585        RefQualifierKind Ref = MD->getRefQualifier();
586        if (Ref == RQ_LValue)
587          POut << " &";
588        else if (Ref == RQ_RValue)
589          POut << " &&";
590      }
591  
592      typedef SmallVector<const ClassTemplateSpecializationDecl *, 8> SpecsTy;
593      SpecsTy Specs;
594      const DeclContext *Ctx = FD->getDeclContext();
595      while (Ctx && isa<NamedDecl>(Ctx)) {
596        const ClassTemplateSpecializationDecl *Spec
597                                 = dyn_cast<ClassTemplateSpecializationDecl>(Ctx);
598        if (Spec && !Spec->isExplicitSpecialization())
599          Specs.push_back(Spec);
600        Ctx = Ctx->getParent();
601      }
602  
603      std::string TemplateParams;
604      llvm::raw_string_ostream TOut(TemplateParams);
605      for (SpecsTy::reverse_iterator I = Specs.rbegin(), E = Specs.rend();
606           I != E; ++I) {
607        const TemplateParameterList *Params
608                    = (*I)->getSpecializedTemplate()->getTemplateParameters();
609        const TemplateArgumentList &Args = (*I)->getTemplateArgs();
610        assert(Params->size() == Args.size());
611        for (unsigned i = 0, numParams = Params->size(); i != numParams; ++i) {
612          StringRef Param = Params->getParam(i)->getName();
613          if (Param.empty()) continue;
614          TOut << Param << " = ";
615          Args.get(i).print(Policy, TOut);
616          TOut << ", ";
617        }
618      }
619  
620      FunctionTemplateSpecializationInfo *FSI
621                                            = FD->getTemplateSpecializationInfo();
622      if (FSI && !FSI->isExplicitSpecialization()) {
623        const TemplateParameterList* Params
624                                    = FSI->getTemplate()->getTemplateParameters();
625        const TemplateArgumentList* Args = FSI->TemplateArguments;
626        assert(Params->size() == Args->size());
627        for (unsigned i = 0, e = Params->size(); i != e; ++i) {
628          StringRef Param = Params->getParam(i)->getName();
629          if (Param.empty()) continue;
630          TOut << Param << " = ";
631          Args->get(i).print(Policy, TOut);
632          TOut << ", ";
633        }
634      }
635  
636      TOut.flush();
637      if (!TemplateParams.empty()) {
638        // remove the trailing comma and space
639        TemplateParams.resize(TemplateParams.size() - 2);
640        POut << " [" << TemplateParams << "]";
641      }
642  
643      POut.flush();
644  
645      // Print "auto" for all deduced return types. This includes C++1y return
646      // type deduction and lambdas. For trailing return types resolve the
647      // decltype expression. Otherwise print the real type when this is
648      // not a constructor or destructor.
649      if (isa<CXXMethodDecl>(FD) &&
650           cast<CXXMethodDecl>(FD)->getParent()->isLambda())
651        Proto = "auto " + Proto;
652      else if (FT && FT->getReturnType()->getAs<DecltypeType>())
653        FT->getReturnType()
654            ->getAs<DecltypeType>()
655            ->getUnderlyingType()
656            .getAsStringInternal(Proto, Policy);
657      else if (!isa<CXXConstructorDecl>(FD) && !isa<CXXDestructorDecl>(FD))
658        AFT->getReturnType().getAsStringInternal(Proto, Policy);
659  
660      Out << Proto;
661  
662      return Name.str().str();
663    }
664    if (const CapturedDecl *CD = dyn_cast<CapturedDecl>(CurrentDecl)) {
665      for (const DeclContext *DC = CD->getParent(); DC; DC = DC->getParent())
666        // Skip to its enclosing function or method, but not its enclosing
667        // CapturedDecl.
668        if (DC->isFunctionOrMethod() && (DC->getDeclKind() != Decl::Captured)) {
669          const Decl *D = Decl::castFromDeclContext(DC);
670          return ComputeName(IT, D);
671        }
672      llvm_unreachable("CapturedDecl not inside a function or method");
673    }
674    if (const ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(CurrentDecl)) {
675      SmallString<256> Name;
676      llvm::raw_svector_ostream Out(Name);
677      Out << (MD->isInstanceMethod() ? '-' : '+');
678      Out << '[';
679  
680      // For incorrect code, there might not be an ObjCInterfaceDecl.  Do
681      // a null check to avoid a crash.
682      if (const ObjCInterfaceDecl *ID = MD->getClassInterface())
683        Out << *ID;
684  
685      if (const ObjCCategoryImplDecl *CID =
686          dyn_cast<ObjCCategoryImplDecl>(MD->getDeclContext()))
687        Out << '(' << *CID << ')';
688  
689      Out <<  ' ';
690      MD->getSelector().print(Out);
691      Out <<  ']';
692  
693      return Name.str().str();
694    }
695    if (isa<TranslationUnitDecl>(CurrentDecl) && IT == PrettyFunction) {
696      // __PRETTY_FUNCTION__ -> "top level", the others produce an empty string.
697      return "top level";
698    }
699    return "";
700  }
701  
setIntValue(const ASTContext & C,const llvm::APInt & Val)702  void APNumericStorage::setIntValue(const ASTContext &C,
703                                     const llvm::APInt &Val) {
704    if (hasAllocation())
705      C.Deallocate(pVal);
706  
707    BitWidth = Val.getBitWidth();
708    unsigned NumWords = Val.getNumWords();
709    const uint64_t* Words = Val.getRawData();
710    if (NumWords > 1) {
711      pVal = new (C) uint64_t[NumWords];
712      std::copy(Words, Words + NumWords, pVal);
713    } else if (NumWords == 1)
714      VAL = Words[0];
715    else
716      VAL = 0;
717  }
718  
IntegerLiteral(const ASTContext & C,const llvm::APInt & V,QualType type,SourceLocation l)719  IntegerLiteral::IntegerLiteral(const ASTContext &C, const llvm::APInt &V,
720                                 QualType type, SourceLocation l)
721    : Expr(IntegerLiteralClass, type, VK_RValue, OK_Ordinary, false, false,
722           false, false),
723      Loc(l) {
724    assert(type->isIntegerType() && "Illegal type in IntegerLiteral");
725    assert(V.getBitWidth() == C.getIntWidth(type) &&
726           "Integer type is not the correct size for constant.");
727    setValue(C, V);
728  }
729  
730  IntegerLiteral *
Create(const ASTContext & C,const llvm::APInt & V,QualType type,SourceLocation l)731  IntegerLiteral::Create(const ASTContext &C, const llvm::APInt &V,
732                         QualType type, SourceLocation l) {
733    return new (C) IntegerLiteral(C, V, type, l);
734  }
735  
736  IntegerLiteral *
Create(const ASTContext & C,EmptyShell Empty)737  IntegerLiteral::Create(const ASTContext &C, EmptyShell Empty) {
738    return new (C) IntegerLiteral(Empty);
739  }
740  
FloatingLiteral(const ASTContext & C,const llvm::APFloat & V,bool isexact,QualType Type,SourceLocation L)741  FloatingLiteral::FloatingLiteral(const ASTContext &C, const llvm::APFloat &V,
742                                   bool isexact, QualType Type, SourceLocation L)
743    : Expr(FloatingLiteralClass, Type, VK_RValue, OK_Ordinary, false, false,
744           false, false), Loc(L) {
745    setSemantics(V.getSemantics());
746    FloatingLiteralBits.IsExact = isexact;
747    setValue(C, V);
748  }
749  
FloatingLiteral(const ASTContext & C,EmptyShell Empty)750  FloatingLiteral::FloatingLiteral(const ASTContext &C, EmptyShell Empty)
751    : Expr(FloatingLiteralClass, Empty) {
752    setRawSemantics(IEEEhalf);
753    FloatingLiteralBits.IsExact = false;
754  }
755  
756  FloatingLiteral *
Create(const ASTContext & C,const llvm::APFloat & V,bool isexact,QualType Type,SourceLocation L)757  FloatingLiteral::Create(const ASTContext &C, const llvm::APFloat &V,
758                          bool isexact, QualType Type, SourceLocation L) {
759    return new (C) FloatingLiteral(C, V, isexact, Type, L);
760  }
761  
762  FloatingLiteral *
Create(const ASTContext & C,EmptyShell Empty)763  FloatingLiteral::Create(const ASTContext &C, EmptyShell Empty) {
764    return new (C) FloatingLiteral(C, Empty);
765  }
766  
getSemantics() const767  const llvm::fltSemantics &FloatingLiteral::getSemantics() const {
768    switch(FloatingLiteralBits.Semantics) {
769    case IEEEhalf:
770      return llvm::APFloat::IEEEhalf;
771    case IEEEsingle:
772      return llvm::APFloat::IEEEsingle;
773    case IEEEdouble:
774      return llvm::APFloat::IEEEdouble;
775    case x87DoubleExtended:
776      return llvm::APFloat::x87DoubleExtended;
777    case IEEEquad:
778      return llvm::APFloat::IEEEquad;
779    case PPCDoubleDouble:
780      return llvm::APFloat::PPCDoubleDouble;
781    }
782    llvm_unreachable("Unrecognised floating semantics");
783  }
784  
setSemantics(const llvm::fltSemantics & Sem)785  void FloatingLiteral::setSemantics(const llvm::fltSemantics &Sem) {
786    if (&Sem == &llvm::APFloat::IEEEhalf)
787      FloatingLiteralBits.Semantics = IEEEhalf;
788    else if (&Sem == &llvm::APFloat::IEEEsingle)
789      FloatingLiteralBits.Semantics = IEEEsingle;
790    else if (&Sem == &llvm::APFloat::IEEEdouble)
791      FloatingLiteralBits.Semantics = IEEEdouble;
792    else if (&Sem == &llvm::APFloat::x87DoubleExtended)
793      FloatingLiteralBits.Semantics = x87DoubleExtended;
794    else if (&Sem == &llvm::APFloat::IEEEquad)
795      FloatingLiteralBits.Semantics = IEEEquad;
796    else if (&Sem == &llvm::APFloat::PPCDoubleDouble)
797      FloatingLiteralBits.Semantics = PPCDoubleDouble;
798    else
799      llvm_unreachable("Unknown floating semantics");
800  }
801  
802  /// getValueAsApproximateDouble - This returns the value as an inaccurate
803  /// double.  Note that this may cause loss of precision, but is useful for
804  /// debugging dumps, etc.
getValueAsApproximateDouble() const805  double FloatingLiteral::getValueAsApproximateDouble() const {
806    llvm::APFloat V = getValue();
807    bool ignored;
808    V.convert(llvm::APFloat::IEEEdouble, llvm::APFloat::rmNearestTiesToEven,
809              &ignored);
810    return V.convertToDouble();
811  }
812  
mapCharByteWidth(TargetInfo const & target,StringKind k)813  int StringLiteral::mapCharByteWidth(TargetInfo const &target,StringKind k) {
814    int CharByteWidth = 0;
815    switch(k) {
816      case Ascii:
817      case UTF8:
818        CharByteWidth = target.getCharWidth();
819        break;
820      case Wide:
821        CharByteWidth = target.getWCharWidth();
822        break;
823      case UTF16:
824        CharByteWidth = target.getChar16Width();
825        break;
826      case UTF32:
827        CharByteWidth = target.getChar32Width();
828        break;
829    }
830    assert((CharByteWidth & 7) == 0 && "Assumes character size is byte multiple");
831    CharByteWidth /= 8;
832    assert((CharByteWidth==1 || CharByteWidth==2 || CharByteWidth==4)
833           && "character byte widths supported are 1, 2, and 4 only");
834    return CharByteWidth;
835  }
836  
Create(const ASTContext & C,StringRef Str,StringKind Kind,bool Pascal,QualType Ty,const SourceLocation * Loc,unsigned NumStrs)837  StringLiteral *StringLiteral::Create(const ASTContext &C, StringRef Str,
838                                       StringKind Kind, bool Pascal, QualType Ty,
839                                       const SourceLocation *Loc,
840                                       unsigned NumStrs) {
841    assert(C.getAsConstantArrayType(Ty) &&
842           "StringLiteral must be of constant array type!");
843  
844    // Allocate enough space for the StringLiteral plus an array of locations for
845    // any concatenated string tokens.
846    void *Mem = C.Allocate(sizeof(StringLiteral)+
847                           sizeof(SourceLocation)*(NumStrs-1),
848                           llvm::alignOf<StringLiteral>());
849    StringLiteral *SL = new (Mem) StringLiteral(Ty);
850  
851    // OPTIMIZE: could allocate this appended to the StringLiteral.
852    SL->setString(C,Str,Kind,Pascal);
853  
854    SL->TokLocs[0] = Loc[0];
855    SL->NumConcatenated = NumStrs;
856  
857    if (NumStrs != 1)
858      memcpy(&SL->TokLocs[1], Loc+1, sizeof(SourceLocation)*(NumStrs-1));
859    return SL;
860  }
861  
CreateEmpty(const ASTContext & C,unsigned NumStrs)862  StringLiteral *StringLiteral::CreateEmpty(const ASTContext &C,
863                                            unsigned NumStrs) {
864    void *Mem = C.Allocate(sizeof(StringLiteral)+
865                           sizeof(SourceLocation)*(NumStrs-1),
866                           llvm::alignOf<StringLiteral>());
867    StringLiteral *SL = new (Mem) StringLiteral(QualType());
868    SL->CharByteWidth = 0;
869    SL->Length = 0;
870    SL->NumConcatenated = NumStrs;
871    return SL;
872  }
873  
outputString(raw_ostream & OS) const874  void StringLiteral::outputString(raw_ostream &OS) const {
875    switch (getKind()) {
876    case Ascii: break; // no prefix.
877    case Wide:  OS << 'L'; break;
878    case UTF8:  OS << "u8"; break;
879    case UTF16: OS << 'u'; break;
880    case UTF32: OS << 'U'; break;
881    }
882    OS << '"';
883    static const char Hex[] = "0123456789ABCDEF";
884  
885    unsigned LastSlashX = getLength();
886    for (unsigned I = 0, N = getLength(); I != N; ++I) {
887      switch (uint32_t Char = getCodeUnit(I)) {
888      default:
889        // FIXME: Convert UTF-8 back to codepoints before rendering.
890  
891        // Convert UTF-16 surrogate pairs back to codepoints before rendering.
892        // Leave invalid surrogates alone; we'll use \x for those.
893        if (getKind() == UTF16 && I != N - 1 && Char >= 0xd800 &&
894            Char <= 0xdbff) {
895          uint32_t Trail = getCodeUnit(I + 1);
896          if (Trail >= 0xdc00 && Trail <= 0xdfff) {
897            Char = 0x10000 + ((Char - 0xd800) << 10) + (Trail - 0xdc00);
898            ++I;
899          }
900        }
901  
902        if (Char > 0xff) {
903          // If this is a wide string, output characters over 0xff using \x
904          // escapes. Otherwise, this is a UTF-16 or UTF-32 string, and Char is a
905          // codepoint: use \x escapes for invalid codepoints.
906          if (getKind() == Wide ||
907              (Char >= 0xd800 && Char <= 0xdfff) || Char >= 0x110000) {
908            // FIXME: Is this the best way to print wchar_t?
909            OS << "\\x";
910            int Shift = 28;
911            while ((Char >> Shift) == 0)
912              Shift -= 4;
913            for (/**/; Shift >= 0; Shift -= 4)
914              OS << Hex[(Char >> Shift) & 15];
915            LastSlashX = I;
916            break;
917          }
918  
919          if (Char > 0xffff)
920            OS << "\\U00"
921               << Hex[(Char >> 20) & 15]
922               << Hex[(Char >> 16) & 15];
923          else
924            OS << "\\u";
925          OS << Hex[(Char >> 12) & 15]
926             << Hex[(Char >>  8) & 15]
927             << Hex[(Char >>  4) & 15]
928             << Hex[(Char >>  0) & 15];
929          break;
930        }
931  
932        // If we used \x... for the previous character, and this character is a
933        // hexadecimal digit, prevent it being slurped as part of the \x.
934        if (LastSlashX + 1 == I) {
935          switch (Char) {
936            case '0': case '1': case '2': case '3': case '4':
937            case '5': case '6': case '7': case '8': case '9':
938            case 'a': case 'b': case 'c': case 'd': case 'e': case 'f':
939            case 'A': case 'B': case 'C': case 'D': case 'E': case 'F':
940              OS << "\"\"";
941          }
942        }
943  
944        assert(Char <= 0xff &&
945               "Characters above 0xff should already have been handled.");
946  
947        if (isPrintable(Char))
948          OS << (char)Char;
949        else  // Output anything hard as an octal escape.
950          OS << '\\'
951             << (char)('0' + ((Char >> 6) & 7))
952             << (char)('0' + ((Char >> 3) & 7))
953             << (char)('0' + ((Char >> 0) & 7));
954        break;
955      // Handle some common non-printable cases to make dumps prettier.
956      case '\\': OS << "\\\\"; break;
957      case '"': OS << "\\\""; break;
958      case '\n': OS << "\\n"; break;
959      case '\t': OS << "\\t"; break;
960      case '\a': OS << "\\a"; break;
961      case '\b': OS << "\\b"; break;
962      }
963    }
964    OS << '"';
965  }
966  
setString(const ASTContext & C,StringRef Str,StringKind Kind,bool IsPascal)967  void StringLiteral::setString(const ASTContext &C, StringRef Str,
968                                StringKind Kind, bool IsPascal) {
969    //FIXME: we assume that the string data comes from a target that uses the same
970    // code unit size and endianess for the type of string.
971    this->Kind = Kind;
972    this->IsPascal = IsPascal;
973  
974    CharByteWidth = mapCharByteWidth(C.getTargetInfo(),Kind);
975    assert((Str.size()%CharByteWidth == 0)
976           && "size of data must be multiple of CharByteWidth");
977    Length = Str.size()/CharByteWidth;
978  
979    switch(CharByteWidth) {
980      case 1: {
981        char *AStrData = new (C) char[Length];
982        std::memcpy(AStrData,Str.data(),Length*sizeof(*AStrData));
983        StrData.asChar = AStrData;
984        break;
985      }
986      case 2: {
987        uint16_t *AStrData = new (C) uint16_t[Length];
988        std::memcpy(AStrData,Str.data(),Length*sizeof(*AStrData));
989        StrData.asUInt16 = AStrData;
990        break;
991      }
992      case 4: {
993        uint32_t *AStrData = new (C) uint32_t[Length];
994        std::memcpy(AStrData,Str.data(),Length*sizeof(*AStrData));
995        StrData.asUInt32 = AStrData;
996        break;
997      }
998      default:
999        assert(false && "unsupported CharByteWidth");
1000    }
1001  }
1002  
1003  /// getLocationOfByte - Return a source location that points to the specified
1004  /// byte of this string literal.
1005  ///
1006  /// Strings are amazingly complex.  They can be formed from multiple tokens and
1007  /// can have escape sequences in them in addition to the usual trigraph and
1008  /// escaped newline business.  This routine handles this complexity.
1009  ///
1010  /// The *StartToken sets the first token to be searched in this function and
1011  /// the *StartTokenByteOffset is the byte offset of the first token. Before
1012  /// returning, it updates the *StartToken to the TokNo of the token being found
1013  /// and sets *StartTokenByteOffset to the byte offset of the token in the
1014  /// string.
1015  /// Using these two parameters can reduce the time complexity from O(n^2) to
1016  /// O(n) if one wants to get the location of byte for all the tokens in a
1017  /// string.
1018  ///
1019  SourceLocation
getLocationOfByte(unsigned ByteNo,const SourceManager & SM,const LangOptions & Features,const TargetInfo & Target,unsigned * StartToken,unsigned * StartTokenByteOffset) const1020  StringLiteral::getLocationOfByte(unsigned ByteNo, const SourceManager &SM,
1021                                   const LangOptions &Features,
1022                                   const TargetInfo &Target, unsigned *StartToken,
1023                                   unsigned *StartTokenByteOffset) const {
1024    assert((Kind == StringLiteral::Ascii || Kind == StringLiteral::UTF8) &&
1025           "Only narrow string literals are currently supported");
1026  
1027    // Loop over all of the tokens in this string until we find the one that
1028    // contains the byte we're looking for.
1029    unsigned TokNo = 0;
1030    unsigned StringOffset = 0;
1031    if (StartToken)
1032      TokNo = *StartToken;
1033    if (StartTokenByteOffset) {
1034      StringOffset = *StartTokenByteOffset;
1035      ByteNo -= StringOffset;
1036    }
1037    while (1) {
1038      assert(TokNo < getNumConcatenated() && "Invalid byte number!");
1039      SourceLocation StrTokLoc = getStrTokenLoc(TokNo);
1040  
1041      // Get the spelling of the string so that we can get the data that makes up
1042      // the string literal, not the identifier for the macro it is potentially
1043      // expanded through.
1044      SourceLocation StrTokSpellingLoc = SM.getSpellingLoc(StrTokLoc);
1045  
1046      // Re-lex the token to get its length and original spelling.
1047      std::pair<FileID, unsigned> LocInfo =
1048          SM.getDecomposedLoc(StrTokSpellingLoc);
1049      bool Invalid = false;
1050      StringRef Buffer = SM.getBufferData(LocInfo.first, &Invalid);
1051      if (Invalid) {
1052        if (StartTokenByteOffset != nullptr)
1053          *StartTokenByteOffset = StringOffset;
1054        if (StartToken != nullptr)
1055          *StartToken = TokNo;
1056        return StrTokSpellingLoc;
1057      }
1058  
1059      const char *StrData = Buffer.data()+LocInfo.second;
1060  
1061      // Create a lexer starting at the beginning of this token.
1062      Lexer TheLexer(SM.getLocForStartOfFile(LocInfo.first), Features,
1063                     Buffer.begin(), StrData, Buffer.end());
1064      Token TheTok;
1065      TheLexer.LexFromRawLexer(TheTok);
1066  
1067      // Use the StringLiteralParser to compute the length of the string in bytes.
1068      StringLiteralParser SLP(TheTok, SM, Features, Target);
1069      unsigned TokNumBytes = SLP.GetStringLength();
1070  
1071      // If the byte is in this token, return the location of the byte.
1072      if (ByteNo < TokNumBytes ||
1073          (ByteNo == TokNumBytes && TokNo == getNumConcatenated() - 1)) {
1074        unsigned Offset = SLP.getOffsetOfStringByte(TheTok, ByteNo);
1075  
1076        // Now that we know the offset of the token in the spelling, use the
1077        // preprocessor to get the offset in the original source.
1078        if (StartTokenByteOffset != nullptr)
1079          *StartTokenByteOffset = StringOffset;
1080        if (StartToken != nullptr)
1081          *StartToken = TokNo;
1082        return Lexer::AdvanceToTokenCharacter(StrTokLoc, Offset, SM, Features);
1083      }
1084  
1085      // Move to the next string token.
1086      StringOffset += TokNumBytes;
1087      ++TokNo;
1088      ByteNo -= TokNumBytes;
1089    }
1090  }
1091  
1092  
1093  
1094  /// getOpcodeStr - Turn an Opcode enum value into the punctuation char it
1095  /// corresponds to, e.g. "sizeof" or "[pre]++".
getOpcodeStr(Opcode Op)1096  StringRef UnaryOperator::getOpcodeStr(Opcode Op) {
1097    switch (Op) {
1098    case UO_PostInc: return "++";
1099    case UO_PostDec: return "--";
1100    case UO_PreInc:  return "++";
1101    case UO_PreDec:  return "--";
1102    case UO_AddrOf:  return "&";
1103    case UO_Deref:   return "*";
1104    case UO_Plus:    return "+";
1105    case UO_Minus:   return "-";
1106    case UO_Not:     return "~";
1107    case UO_LNot:    return "!";
1108    case UO_Real:    return "__real";
1109    case UO_Imag:    return "__imag";
1110    case UO_Extension: return "__extension__";
1111    case UO_Coawait: return "co_await";
1112    }
1113    llvm_unreachable("Unknown unary operator");
1114  }
1115  
1116  UnaryOperatorKind
getOverloadedOpcode(OverloadedOperatorKind OO,bool Postfix)1117  UnaryOperator::getOverloadedOpcode(OverloadedOperatorKind OO, bool Postfix) {
1118    switch (OO) {
1119    default: llvm_unreachable("No unary operator for overloaded function");
1120    case OO_PlusPlus:   return Postfix ? UO_PostInc : UO_PreInc;
1121    case OO_MinusMinus: return Postfix ? UO_PostDec : UO_PreDec;
1122    case OO_Amp:        return UO_AddrOf;
1123    case OO_Star:       return UO_Deref;
1124    case OO_Plus:       return UO_Plus;
1125    case OO_Minus:      return UO_Minus;
1126    case OO_Tilde:      return UO_Not;
1127    case OO_Exclaim:    return UO_LNot;
1128    case OO_Coawait:    return UO_Coawait;
1129    }
1130  }
1131  
getOverloadedOperator(Opcode Opc)1132  OverloadedOperatorKind UnaryOperator::getOverloadedOperator(Opcode Opc) {
1133    switch (Opc) {
1134    case UO_PostInc: case UO_PreInc: return OO_PlusPlus;
1135    case UO_PostDec: case UO_PreDec: return OO_MinusMinus;
1136    case UO_AddrOf: return OO_Amp;
1137    case UO_Deref: return OO_Star;
1138    case UO_Plus: return OO_Plus;
1139    case UO_Minus: return OO_Minus;
1140    case UO_Not: return OO_Tilde;
1141    case UO_LNot: return OO_Exclaim;
1142    case UO_Coawait: return OO_Coawait;
1143    default: return OO_None;
1144    }
1145  }
1146  
1147  
1148  //===----------------------------------------------------------------------===//
1149  // Postfix Operators.
1150  //===----------------------------------------------------------------------===//
1151  
CallExpr(const ASTContext & C,StmtClass SC,Expr * fn,unsigned NumPreArgs,ArrayRef<Expr * > args,QualType t,ExprValueKind VK,SourceLocation rparenloc)1152  CallExpr::CallExpr(const ASTContext& C, StmtClass SC, Expr *fn,
1153                     unsigned NumPreArgs, ArrayRef<Expr*> args, QualType t,
1154                     ExprValueKind VK, SourceLocation rparenloc)
1155    : Expr(SC, t, VK, OK_Ordinary,
1156           fn->isTypeDependent(),
1157           fn->isValueDependent(),
1158           fn->isInstantiationDependent(),
1159           fn->containsUnexpandedParameterPack()),
1160      NumArgs(args.size()) {
1161  
1162    SubExprs = new (C) Stmt*[args.size()+PREARGS_START+NumPreArgs];
1163    SubExprs[FN] = fn;
1164    for (unsigned i = 0; i != args.size(); ++i) {
1165      if (args[i]->isTypeDependent())
1166        ExprBits.TypeDependent = true;
1167      if (args[i]->isValueDependent())
1168        ExprBits.ValueDependent = true;
1169      if (args[i]->isInstantiationDependent())
1170        ExprBits.InstantiationDependent = true;
1171      if (args[i]->containsUnexpandedParameterPack())
1172        ExprBits.ContainsUnexpandedParameterPack = true;
1173  
1174      SubExprs[i+PREARGS_START+NumPreArgs] = args[i];
1175    }
1176  
1177    CallExprBits.NumPreArgs = NumPreArgs;
1178    RParenLoc = rparenloc;
1179  }
1180  
CallExpr(const ASTContext & C,Expr * fn,ArrayRef<Expr * > args,QualType t,ExprValueKind VK,SourceLocation rparenloc)1181  CallExpr::CallExpr(const ASTContext &C, Expr *fn, ArrayRef<Expr *> args,
1182                     QualType t, ExprValueKind VK, SourceLocation rparenloc)
1183      : CallExpr(C, CallExprClass, fn, /*NumPreArgs=*/0, args, t, VK, rparenloc) {
1184  }
1185  
CallExpr(const ASTContext & C,StmtClass SC,EmptyShell Empty)1186  CallExpr::CallExpr(const ASTContext &C, StmtClass SC, EmptyShell Empty)
1187      : CallExpr(C, SC, /*NumPreArgs=*/0, Empty) {}
1188  
CallExpr(const ASTContext & C,StmtClass SC,unsigned NumPreArgs,EmptyShell Empty)1189  CallExpr::CallExpr(const ASTContext &C, StmtClass SC, unsigned NumPreArgs,
1190                     EmptyShell Empty)
1191    : Expr(SC, Empty), SubExprs(nullptr), NumArgs(0) {
1192    // FIXME: Why do we allocate this?
1193    SubExprs = new (C) Stmt*[PREARGS_START+NumPreArgs];
1194    CallExprBits.NumPreArgs = NumPreArgs;
1195  }
1196  
getCalleeDecl()1197  Decl *CallExpr::getCalleeDecl() {
1198    Expr *CEE = getCallee()->IgnoreParenImpCasts();
1199  
1200    while (SubstNonTypeTemplateParmExpr *NTTP
1201                                  = dyn_cast<SubstNonTypeTemplateParmExpr>(CEE)) {
1202      CEE = NTTP->getReplacement()->IgnoreParenCasts();
1203    }
1204  
1205    // If we're calling a dereference, look at the pointer instead.
1206    if (BinaryOperator *BO = dyn_cast<BinaryOperator>(CEE)) {
1207      if (BO->isPtrMemOp())
1208        CEE = BO->getRHS()->IgnoreParenCasts();
1209    } else if (UnaryOperator *UO = dyn_cast<UnaryOperator>(CEE)) {
1210      if (UO->getOpcode() == UO_Deref)
1211        CEE = UO->getSubExpr()->IgnoreParenCasts();
1212    }
1213    if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CEE))
1214      return DRE->getDecl();
1215    if (MemberExpr *ME = dyn_cast<MemberExpr>(CEE))
1216      return ME->getMemberDecl();
1217  
1218    return nullptr;
1219  }
1220  
getDirectCallee()1221  FunctionDecl *CallExpr::getDirectCallee() {
1222    return dyn_cast_or_null<FunctionDecl>(getCalleeDecl());
1223  }
1224  
1225  /// setNumArgs - This changes the number of arguments present in this call.
1226  /// Any orphaned expressions are deleted by this, and any new operands are set
1227  /// to null.
setNumArgs(const ASTContext & C,unsigned NumArgs)1228  void CallExpr::setNumArgs(const ASTContext& C, unsigned NumArgs) {
1229    // No change, just return.
1230    if (NumArgs == getNumArgs()) return;
1231  
1232    // If shrinking # arguments, just delete the extras and forgot them.
1233    if (NumArgs < getNumArgs()) {
1234      this->NumArgs = NumArgs;
1235      return;
1236    }
1237  
1238    // Otherwise, we are growing the # arguments.  New an bigger argument array.
1239    unsigned NumPreArgs = getNumPreArgs();
1240    Stmt **NewSubExprs = new (C) Stmt*[NumArgs+PREARGS_START+NumPreArgs];
1241    // Copy over args.
1242    for (unsigned i = 0; i != getNumArgs()+PREARGS_START+NumPreArgs; ++i)
1243      NewSubExprs[i] = SubExprs[i];
1244    // Null out new args.
1245    for (unsigned i = getNumArgs()+PREARGS_START+NumPreArgs;
1246         i != NumArgs+PREARGS_START+NumPreArgs; ++i)
1247      NewSubExprs[i] = nullptr;
1248  
1249    if (SubExprs) C.Deallocate(SubExprs);
1250    SubExprs = NewSubExprs;
1251    this->NumArgs = NumArgs;
1252  }
1253  
1254  /// getBuiltinCallee - If this is a call to a builtin, return the builtin ID. If
1255  /// not, return 0.
getBuiltinCallee() const1256  unsigned CallExpr::getBuiltinCallee() const {
1257    // All simple function calls (e.g. func()) are implicitly cast to pointer to
1258    // function. As a result, we try and obtain the DeclRefExpr from the
1259    // ImplicitCastExpr.
1260    const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(getCallee());
1261    if (!ICE) // FIXME: deal with more complex calls (e.g. (func)(), (*func)()).
1262      return 0;
1263  
1264    const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(ICE->getSubExpr());
1265    if (!DRE)
1266      return 0;
1267  
1268    const FunctionDecl *FDecl = dyn_cast<FunctionDecl>(DRE->getDecl());
1269    if (!FDecl)
1270      return 0;
1271  
1272    if (!FDecl->getIdentifier())
1273      return 0;
1274  
1275    return FDecl->getBuiltinID();
1276  }
1277  
isUnevaluatedBuiltinCall(const ASTContext & Ctx) const1278  bool CallExpr::isUnevaluatedBuiltinCall(const ASTContext &Ctx) const {
1279    if (unsigned BI = getBuiltinCallee())
1280      return Ctx.BuiltinInfo.isUnevaluated(BI);
1281    return false;
1282  }
1283  
getCallReturnType(const ASTContext & Ctx) const1284  QualType CallExpr::getCallReturnType(const ASTContext &Ctx) const {
1285    const Expr *Callee = getCallee();
1286    QualType CalleeType = Callee->getType();
1287    if (const auto *FnTypePtr = CalleeType->getAs<PointerType>()) {
1288      CalleeType = FnTypePtr->getPointeeType();
1289    } else if (const auto *BPT = CalleeType->getAs<BlockPointerType>()) {
1290      CalleeType = BPT->getPointeeType();
1291    } else if (CalleeType->isSpecificPlaceholderType(BuiltinType::BoundMember)) {
1292      if (isa<CXXPseudoDestructorExpr>(Callee->IgnoreParens()))
1293        return Ctx.VoidTy;
1294  
1295      // This should never be overloaded and so should never return null.
1296      CalleeType = Expr::findBoundMemberType(Callee);
1297    }
1298  
1299    const FunctionType *FnType = CalleeType->castAs<FunctionType>();
1300    return FnType->getReturnType();
1301  }
1302  
getLocStart() const1303  SourceLocation CallExpr::getLocStart() const {
1304    if (isa<CXXOperatorCallExpr>(this))
1305      return cast<CXXOperatorCallExpr>(this)->getLocStart();
1306  
1307    SourceLocation begin = getCallee()->getLocStart();
1308    if (begin.isInvalid() && getNumArgs() > 0 && getArg(0))
1309      begin = getArg(0)->getLocStart();
1310    return begin;
1311  }
getLocEnd() const1312  SourceLocation CallExpr::getLocEnd() const {
1313    if (isa<CXXOperatorCallExpr>(this))
1314      return cast<CXXOperatorCallExpr>(this)->getLocEnd();
1315  
1316    SourceLocation end = getRParenLoc();
1317    if (end.isInvalid() && getNumArgs() > 0 && getArg(getNumArgs() - 1))
1318      end = getArg(getNumArgs() - 1)->getLocEnd();
1319    return end;
1320  }
1321  
Create(const ASTContext & C,QualType type,SourceLocation OperatorLoc,TypeSourceInfo * tsi,ArrayRef<OffsetOfNode> comps,ArrayRef<Expr * > exprs,SourceLocation RParenLoc)1322  OffsetOfExpr *OffsetOfExpr::Create(const ASTContext &C, QualType type,
1323                                     SourceLocation OperatorLoc,
1324                                     TypeSourceInfo *tsi,
1325                                     ArrayRef<OffsetOfNode> comps,
1326                                     ArrayRef<Expr*> exprs,
1327                                     SourceLocation RParenLoc) {
1328    void *Mem = C.Allocate(sizeof(OffsetOfExpr) +
1329                           sizeof(OffsetOfNode) * comps.size() +
1330                           sizeof(Expr*) * exprs.size());
1331  
1332    return new (Mem) OffsetOfExpr(C, type, OperatorLoc, tsi, comps, exprs,
1333                                  RParenLoc);
1334  }
1335  
CreateEmpty(const ASTContext & C,unsigned numComps,unsigned numExprs)1336  OffsetOfExpr *OffsetOfExpr::CreateEmpty(const ASTContext &C,
1337                                          unsigned numComps, unsigned numExprs) {
1338    void *Mem = C.Allocate(sizeof(OffsetOfExpr) +
1339                           sizeof(OffsetOfNode) * numComps +
1340                           sizeof(Expr*) * numExprs);
1341    return new (Mem) OffsetOfExpr(numComps, numExprs);
1342  }
1343  
OffsetOfExpr(const ASTContext & C,QualType type,SourceLocation OperatorLoc,TypeSourceInfo * tsi,ArrayRef<OffsetOfNode> comps,ArrayRef<Expr * > exprs,SourceLocation RParenLoc)1344  OffsetOfExpr::OffsetOfExpr(const ASTContext &C, QualType type,
1345                             SourceLocation OperatorLoc, TypeSourceInfo *tsi,
1346                             ArrayRef<OffsetOfNode> comps, ArrayRef<Expr*> exprs,
1347                             SourceLocation RParenLoc)
1348    : Expr(OffsetOfExprClass, type, VK_RValue, OK_Ordinary,
1349           /*TypeDependent=*/false,
1350           /*ValueDependent=*/tsi->getType()->isDependentType(),
1351           tsi->getType()->isInstantiationDependentType(),
1352           tsi->getType()->containsUnexpandedParameterPack()),
1353      OperatorLoc(OperatorLoc), RParenLoc(RParenLoc), TSInfo(tsi),
1354      NumComps(comps.size()), NumExprs(exprs.size())
1355  {
1356    for (unsigned i = 0; i != comps.size(); ++i) {
1357      setComponent(i, comps[i]);
1358    }
1359  
1360    for (unsigned i = 0; i != exprs.size(); ++i) {
1361      if (exprs[i]->isTypeDependent() || exprs[i]->isValueDependent())
1362        ExprBits.ValueDependent = true;
1363      if (exprs[i]->containsUnexpandedParameterPack())
1364        ExprBits.ContainsUnexpandedParameterPack = true;
1365  
1366      setIndexExpr(i, exprs[i]);
1367    }
1368  }
1369  
getFieldName() const1370  IdentifierInfo *OffsetOfExpr::OffsetOfNode::getFieldName() const {
1371    assert(getKind() == Field || getKind() == Identifier);
1372    if (getKind() == Field)
1373      return getField()->getIdentifier();
1374  
1375    return reinterpret_cast<IdentifierInfo *> (Data & ~(uintptr_t)Mask);
1376  }
1377  
UnaryExprOrTypeTraitExpr(UnaryExprOrTypeTrait ExprKind,Expr * E,QualType resultType,SourceLocation op,SourceLocation rp)1378  UnaryExprOrTypeTraitExpr::UnaryExprOrTypeTraitExpr(
1379      UnaryExprOrTypeTrait ExprKind, Expr *E, QualType resultType,
1380      SourceLocation op, SourceLocation rp)
1381      : Expr(UnaryExprOrTypeTraitExprClass, resultType, VK_RValue, OK_Ordinary,
1382             false, // Never type-dependent (C++ [temp.dep.expr]p3).
1383             // Value-dependent if the argument is type-dependent.
1384             E->isTypeDependent(), E->isInstantiationDependent(),
1385             E->containsUnexpandedParameterPack()),
1386        OpLoc(op), RParenLoc(rp) {
1387    UnaryExprOrTypeTraitExprBits.Kind = ExprKind;
1388    UnaryExprOrTypeTraitExprBits.IsType = false;
1389    Argument.Ex = E;
1390  
1391    // Check to see if we are in the situation where alignof(decl) should be
1392    // dependent because decl's alignment is dependent.
1393    if (ExprKind == UETT_AlignOf) {
1394      if (!isValueDependent() || !isInstantiationDependent()) {
1395        E = E->IgnoreParens();
1396  
1397        const ValueDecl *D = nullptr;
1398        if (const auto *DRE = dyn_cast<DeclRefExpr>(E))
1399          D = DRE->getDecl();
1400        else if (const auto *ME = dyn_cast<MemberExpr>(E))
1401          D = ME->getMemberDecl();
1402  
1403        if (D) {
1404          for (const auto *I : D->specific_attrs<AlignedAttr>()) {
1405            if (I->isAlignmentDependent()) {
1406              setValueDependent(true);
1407              setInstantiationDependent(true);
1408              break;
1409            }
1410          }
1411        }
1412      }
1413    }
1414  }
1415  
Create(const ASTContext & C,Expr * base,bool isarrow,SourceLocation OperatorLoc,NestedNameSpecifierLoc QualifierLoc,SourceLocation TemplateKWLoc,ValueDecl * memberdecl,DeclAccessPair founddecl,DeclarationNameInfo nameinfo,const TemplateArgumentListInfo * targs,QualType ty,ExprValueKind vk,ExprObjectKind ok)1416  MemberExpr *MemberExpr::Create(
1417      const ASTContext &C, Expr *base, bool isarrow, SourceLocation OperatorLoc,
1418      NestedNameSpecifierLoc QualifierLoc, SourceLocation TemplateKWLoc,
1419      ValueDecl *memberdecl, DeclAccessPair founddecl,
1420      DeclarationNameInfo nameinfo, const TemplateArgumentListInfo *targs,
1421      QualType ty, ExprValueKind vk, ExprObjectKind ok) {
1422    std::size_t Size = sizeof(MemberExpr);
1423  
1424    bool hasQualOrFound = (QualifierLoc ||
1425                           founddecl.getDecl() != memberdecl ||
1426                           founddecl.getAccess() != memberdecl->getAccess());
1427    if (hasQualOrFound)
1428      Size += sizeof(MemberNameQualifier);
1429  
1430    if (targs)
1431      Size += ASTTemplateKWAndArgsInfo::sizeFor(targs->size());
1432    else if (TemplateKWLoc.isValid())
1433      Size += ASTTemplateKWAndArgsInfo::sizeFor(0);
1434  
1435    void *Mem = C.Allocate(Size, llvm::alignOf<MemberExpr>());
1436    MemberExpr *E = new (Mem)
1437        MemberExpr(base, isarrow, OperatorLoc, memberdecl, nameinfo, ty, vk, ok);
1438  
1439    if (hasQualOrFound) {
1440      // FIXME: Wrong. We should be looking at the member declaration we found.
1441      if (QualifierLoc && QualifierLoc.getNestedNameSpecifier()->isDependent()) {
1442        E->setValueDependent(true);
1443        E->setTypeDependent(true);
1444        E->setInstantiationDependent(true);
1445      }
1446      else if (QualifierLoc &&
1447               QualifierLoc.getNestedNameSpecifier()->isInstantiationDependent())
1448        E->setInstantiationDependent(true);
1449  
1450      E->HasQualifierOrFoundDecl = true;
1451  
1452      MemberNameQualifier *NQ = E->getMemberQualifier();
1453      NQ->QualifierLoc = QualifierLoc;
1454      NQ->FoundDecl = founddecl;
1455    }
1456  
1457    E->HasTemplateKWAndArgsInfo = (targs || TemplateKWLoc.isValid());
1458  
1459    if (targs) {
1460      bool Dependent = false;
1461      bool InstantiationDependent = false;
1462      bool ContainsUnexpandedParameterPack = false;
1463      E->getTemplateKWAndArgsInfo()->initializeFrom(TemplateKWLoc, *targs,
1464                                                    Dependent,
1465                                                    InstantiationDependent,
1466                                               ContainsUnexpandedParameterPack);
1467      if (InstantiationDependent)
1468        E->setInstantiationDependent(true);
1469    } else if (TemplateKWLoc.isValid()) {
1470      E->getTemplateKWAndArgsInfo()->initializeFrom(TemplateKWLoc);
1471    }
1472  
1473    return E;
1474  }
1475  
getLocStart() const1476  SourceLocation MemberExpr::getLocStart() const {
1477    if (isImplicitAccess()) {
1478      if (hasQualifier())
1479        return getQualifierLoc().getBeginLoc();
1480      return MemberLoc;
1481    }
1482  
1483    // FIXME: We don't want this to happen. Rather, we should be able to
1484    // detect all kinds of implicit accesses more cleanly.
1485    SourceLocation BaseStartLoc = getBase()->getLocStart();
1486    if (BaseStartLoc.isValid())
1487      return BaseStartLoc;
1488    return MemberLoc;
1489  }
getLocEnd() const1490  SourceLocation MemberExpr::getLocEnd() const {
1491    SourceLocation EndLoc = getMemberNameInfo().getEndLoc();
1492    if (hasExplicitTemplateArgs())
1493      EndLoc = getRAngleLoc();
1494    else if (EndLoc.isInvalid())
1495      EndLoc = getBase()->getLocEnd();
1496    return EndLoc;
1497  }
1498  
CastConsistency() const1499  bool CastExpr::CastConsistency() const {
1500    switch (getCastKind()) {
1501    case CK_DerivedToBase:
1502    case CK_UncheckedDerivedToBase:
1503    case CK_DerivedToBaseMemberPointer:
1504    case CK_BaseToDerived:
1505    case CK_BaseToDerivedMemberPointer:
1506      assert(!path_empty() && "Cast kind should have a base path!");
1507      break;
1508  
1509    case CK_CPointerToObjCPointerCast:
1510      assert(getType()->isObjCObjectPointerType());
1511      assert(getSubExpr()->getType()->isPointerType());
1512      goto CheckNoBasePath;
1513  
1514    case CK_BlockPointerToObjCPointerCast:
1515      assert(getType()->isObjCObjectPointerType());
1516      assert(getSubExpr()->getType()->isBlockPointerType());
1517      goto CheckNoBasePath;
1518  
1519    case CK_ReinterpretMemberPointer:
1520      assert(getType()->isMemberPointerType());
1521      assert(getSubExpr()->getType()->isMemberPointerType());
1522      goto CheckNoBasePath;
1523  
1524    case CK_BitCast:
1525      // Arbitrary casts to C pointer types count as bitcasts.
1526      // Otherwise, we should only have block and ObjC pointer casts
1527      // here if they stay within the type kind.
1528      if (!getType()->isPointerType()) {
1529        assert(getType()->isObjCObjectPointerType() ==
1530               getSubExpr()->getType()->isObjCObjectPointerType());
1531        assert(getType()->isBlockPointerType() ==
1532               getSubExpr()->getType()->isBlockPointerType());
1533      }
1534      goto CheckNoBasePath;
1535  
1536    case CK_AnyPointerToBlockPointerCast:
1537      assert(getType()->isBlockPointerType());
1538      assert(getSubExpr()->getType()->isAnyPointerType() &&
1539             !getSubExpr()->getType()->isBlockPointerType());
1540      goto CheckNoBasePath;
1541  
1542    case CK_CopyAndAutoreleaseBlockObject:
1543      assert(getType()->isBlockPointerType());
1544      assert(getSubExpr()->getType()->isBlockPointerType());
1545      goto CheckNoBasePath;
1546  
1547    case CK_FunctionToPointerDecay:
1548      assert(getType()->isPointerType());
1549      assert(getSubExpr()->getType()->isFunctionType());
1550      goto CheckNoBasePath;
1551  
1552    case CK_AddressSpaceConversion:
1553      assert(getType()->isPointerType());
1554      assert(getSubExpr()->getType()->isPointerType());
1555      assert(getType()->getPointeeType().getAddressSpace() !=
1556             getSubExpr()->getType()->getPointeeType().getAddressSpace());
1557    // These should not have an inheritance path.
1558    case CK_Dynamic:
1559    case CK_ToUnion:
1560    case CK_ArrayToPointerDecay:
1561    case CK_NullToMemberPointer:
1562    case CK_NullToPointer:
1563    case CK_ConstructorConversion:
1564    case CK_IntegralToPointer:
1565    case CK_PointerToIntegral:
1566    case CK_ToVoid:
1567    case CK_VectorSplat:
1568    case CK_IntegralCast:
1569    case CK_IntegralToFloating:
1570    case CK_FloatingToIntegral:
1571    case CK_FloatingCast:
1572    case CK_ObjCObjectLValueCast:
1573    case CK_FloatingRealToComplex:
1574    case CK_FloatingComplexToReal:
1575    case CK_FloatingComplexCast:
1576    case CK_FloatingComplexToIntegralComplex:
1577    case CK_IntegralRealToComplex:
1578    case CK_IntegralComplexToReal:
1579    case CK_IntegralComplexCast:
1580    case CK_IntegralComplexToFloatingComplex:
1581    case CK_ARCProduceObject:
1582    case CK_ARCConsumeObject:
1583    case CK_ARCReclaimReturnedObject:
1584    case CK_ARCExtendBlockObject:
1585    case CK_ZeroToOCLEvent:
1586      assert(!getType()->isBooleanType() && "unheralded conversion to bool");
1587      goto CheckNoBasePath;
1588  
1589    case CK_Dependent:
1590    case CK_LValueToRValue:
1591    case CK_NoOp:
1592    case CK_AtomicToNonAtomic:
1593    case CK_NonAtomicToAtomic:
1594    case CK_PointerToBoolean:
1595    case CK_IntegralToBoolean:
1596    case CK_FloatingToBoolean:
1597    case CK_MemberPointerToBoolean:
1598    case CK_FloatingComplexToBoolean:
1599    case CK_IntegralComplexToBoolean:
1600    case CK_LValueBitCast:            // -> bool&
1601    case CK_UserDefinedConversion:    // operator bool()
1602    case CK_BuiltinFnToFnPtr:
1603    CheckNoBasePath:
1604      assert(path_empty() && "Cast kind should not have a base path!");
1605      break;
1606    }
1607    return true;
1608  }
1609  
getCastKindName() const1610  const char *CastExpr::getCastKindName() const {
1611    switch (getCastKind()) {
1612    case CK_Dependent:
1613      return "Dependent";
1614    case CK_BitCast:
1615      return "BitCast";
1616    case CK_LValueBitCast:
1617      return "LValueBitCast";
1618    case CK_LValueToRValue:
1619      return "LValueToRValue";
1620    case CK_NoOp:
1621      return "NoOp";
1622    case CK_BaseToDerived:
1623      return "BaseToDerived";
1624    case CK_DerivedToBase:
1625      return "DerivedToBase";
1626    case CK_UncheckedDerivedToBase:
1627      return "UncheckedDerivedToBase";
1628    case CK_Dynamic:
1629      return "Dynamic";
1630    case CK_ToUnion:
1631      return "ToUnion";
1632    case CK_ArrayToPointerDecay:
1633      return "ArrayToPointerDecay";
1634    case CK_FunctionToPointerDecay:
1635      return "FunctionToPointerDecay";
1636    case CK_NullToMemberPointer:
1637      return "NullToMemberPointer";
1638    case CK_NullToPointer:
1639      return "NullToPointer";
1640    case CK_BaseToDerivedMemberPointer:
1641      return "BaseToDerivedMemberPointer";
1642    case CK_DerivedToBaseMemberPointer:
1643      return "DerivedToBaseMemberPointer";
1644    case CK_ReinterpretMemberPointer:
1645      return "ReinterpretMemberPointer";
1646    case CK_UserDefinedConversion:
1647      return "UserDefinedConversion";
1648    case CK_ConstructorConversion:
1649      return "ConstructorConversion";
1650    case CK_IntegralToPointer:
1651      return "IntegralToPointer";
1652    case CK_PointerToIntegral:
1653      return "PointerToIntegral";
1654    case CK_PointerToBoolean:
1655      return "PointerToBoolean";
1656    case CK_ToVoid:
1657      return "ToVoid";
1658    case CK_VectorSplat:
1659      return "VectorSplat";
1660    case CK_IntegralCast:
1661      return "IntegralCast";
1662    case CK_IntegralToBoolean:
1663      return "IntegralToBoolean";
1664    case CK_IntegralToFloating:
1665      return "IntegralToFloating";
1666    case CK_FloatingToIntegral:
1667      return "FloatingToIntegral";
1668    case CK_FloatingCast:
1669      return "FloatingCast";
1670    case CK_FloatingToBoolean:
1671      return "FloatingToBoolean";
1672    case CK_MemberPointerToBoolean:
1673      return "MemberPointerToBoolean";
1674    case CK_CPointerToObjCPointerCast:
1675      return "CPointerToObjCPointerCast";
1676    case CK_BlockPointerToObjCPointerCast:
1677      return "BlockPointerToObjCPointerCast";
1678    case CK_AnyPointerToBlockPointerCast:
1679      return "AnyPointerToBlockPointerCast";
1680    case CK_ObjCObjectLValueCast:
1681      return "ObjCObjectLValueCast";
1682    case CK_FloatingRealToComplex:
1683      return "FloatingRealToComplex";
1684    case CK_FloatingComplexToReal:
1685      return "FloatingComplexToReal";
1686    case CK_FloatingComplexToBoolean:
1687      return "FloatingComplexToBoolean";
1688    case CK_FloatingComplexCast:
1689      return "FloatingComplexCast";
1690    case CK_FloatingComplexToIntegralComplex:
1691      return "FloatingComplexToIntegralComplex";
1692    case CK_IntegralRealToComplex:
1693      return "IntegralRealToComplex";
1694    case CK_IntegralComplexToReal:
1695      return "IntegralComplexToReal";
1696    case CK_IntegralComplexToBoolean:
1697      return "IntegralComplexToBoolean";
1698    case CK_IntegralComplexCast:
1699      return "IntegralComplexCast";
1700    case CK_IntegralComplexToFloatingComplex:
1701      return "IntegralComplexToFloatingComplex";
1702    case CK_ARCConsumeObject:
1703      return "ARCConsumeObject";
1704    case CK_ARCProduceObject:
1705      return "ARCProduceObject";
1706    case CK_ARCReclaimReturnedObject:
1707      return "ARCReclaimReturnedObject";
1708    case CK_ARCExtendBlockObject:
1709      return "ARCExtendBlockObject";
1710    case CK_AtomicToNonAtomic:
1711      return "AtomicToNonAtomic";
1712    case CK_NonAtomicToAtomic:
1713      return "NonAtomicToAtomic";
1714    case CK_CopyAndAutoreleaseBlockObject:
1715      return "CopyAndAutoreleaseBlockObject";
1716    case CK_BuiltinFnToFnPtr:
1717      return "BuiltinFnToFnPtr";
1718    case CK_ZeroToOCLEvent:
1719      return "ZeroToOCLEvent";
1720    case CK_AddressSpaceConversion:
1721      return "AddressSpaceConversion";
1722    }
1723  
1724    llvm_unreachable("Unhandled cast kind!");
1725  }
1726  
getSubExprAsWritten()1727  Expr *CastExpr::getSubExprAsWritten() {
1728    Expr *SubExpr = nullptr;
1729    CastExpr *E = this;
1730    do {
1731      SubExpr = E->getSubExpr();
1732  
1733      // Skip through reference binding to temporary.
1734      if (MaterializeTemporaryExpr *Materialize
1735                                    = dyn_cast<MaterializeTemporaryExpr>(SubExpr))
1736        SubExpr = Materialize->GetTemporaryExpr();
1737  
1738      // Skip any temporary bindings; they're implicit.
1739      if (CXXBindTemporaryExpr *Binder = dyn_cast<CXXBindTemporaryExpr>(SubExpr))
1740        SubExpr = Binder->getSubExpr();
1741  
1742      // Conversions by constructor and conversion functions have a
1743      // subexpression describing the call; strip it off.
1744      if (E->getCastKind() == CK_ConstructorConversion)
1745        SubExpr = cast<CXXConstructExpr>(SubExpr)->getArg(0);
1746      else if (E->getCastKind() == CK_UserDefinedConversion)
1747        SubExpr = cast<CXXMemberCallExpr>(SubExpr)->getImplicitObjectArgument();
1748  
1749      // If the subexpression we're left with is an implicit cast, look
1750      // through that, too.
1751    } while ((E = dyn_cast<ImplicitCastExpr>(SubExpr)));
1752  
1753    return SubExpr;
1754  }
1755  
path_buffer()1756  CXXBaseSpecifier **CastExpr::path_buffer() {
1757    switch (getStmtClass()) {
1758  #define ABSTRACT_STMT(x)
1759  #define CASTEXPR(Type, Base) \
1760    case Stmt::Type##Class: \
1761      return reinterpret_cast<CXXBaseSpecifier**>(static_cast<Type*>(this)+1);
1762  #define STMT(Type, Base)
1763  #include "clang/AST/StmtNodes.inc"
1764    default:
1765      llvm_unreachable("non-cast expressions not possible here");
1766    }
1767  }
1768  
setCastPath(const CXXCastPath & Path)1769  void CastExpr::setCastPath(const CXXCastPath &Path) {
1770    assert(Path.size() == path_size());
1771    memcpy(path_buffer(), Path.data(), Path.size() * sizeof(CXXBaseSpecifier*));
1772  }
1773  
Create(const ASTContext & C,QualType T,CastKind Kind,Expr * Operand,const CXXCastPath * BasePath,ExprValueKind VK)1774  ImplicitCastExpr *ImplicitCastExpr::Create(const ASTContext &C, QualType T,
1775                                             CastKind Kind, Expr *Operand,
1776                                             const CXXCastPath *BasePath,
1777                                             ExprValueKind VK) {
1778    unsigned PathSize = (BasePath ? BasePath->size() : 0);
1779    void *Buffer =
1780      C.Allocate(sizeof(ImplicitCastExpr) + PathSize * sizeof(CXXBaseSpecifier*));
1781    ImplicitCastExpr *E =
1782      new (Buffer) ImplicitCastExpr(T, Kind, Operand, PathSize, VK);
1783    if (PathSize) E->setCastPath(*BasePath);
1784    return E;
1785  }
1786  
CreateEmpty(const ASTContext & C,unsigned PathSize)1787  ImplicitCastExpr *ImplicitCastExpr::CreateEmpty(const ASTContext &C,
1788                                                  unsigned PathSize) {
1789    void *Buffer =
1790      C.Allocate(sizeof(ImplicitCastExpr) + PathSize * sizeof(CXXBaseSpecifier*));
1791    return new (Buffer) ImplicitCastExpr(EmptyShell(), PathSize);
1792  }
1793  
1794  
Create(const ASTContext & C,QualType T,ExprValueKind VK,CastKind K,Expr * Op,const CXXCastPath * BasePath,TypeSourceInfo * WrittenTy,SourceLocation L,SourceLocation R)1795  CStyleCastExpr *CStyleCastExpr::Create(const ASTContext &C, QualType T,
1796                                         ExprValueKind VK, CastKind K, Expr *Op,
1797                                         const CXXCastPath *BasePath,
1798                                         TypeSourceInfo *WrittenTy,
1799                                         SourceLocation L, SourceLocation R) {
1800    unsigned PathSize = (BasePath ? BasePath->size() : 0);
1801    void *Buffer =
1802      C.Allocate(sizeof(CStyleCastExpr) + PathSize * sizeof(CXXBaseSpecifier*));
1803    CStyleCastExpr *E =
1804      new (Buffer) CStyleCastExpr(T, VK, K, Op, PathSize, WrittenTy, L, R);
1805    if (PathSize) E->setCastPath(*BasePath);
1806    return E;
1807  }
1808  
CreateEmpty(const ASTContext & C,unsigned PathSize)1809  CStyleCastExpr *CStyleCastExpr::CreateEmpty(const ASTContext &C,
1810                                              unsigned PathSize) {
1811    void *Buffer =
1812      C.Allocate(sizeof(CStyleCastExpr) + PathSize * sizeof(CXXBaseSpecifier*));
1813    return new (Buffer) CStyleCastExpr(EmptyShell(), PathSize);
1814  }
1815  
1816  /// getOpcodeStr - Turn an Opcode enum value into the punctuation char it
1817  /// corresponds to, e.g. "<<=".
getOpcodeStr(Opcode Op)1818  StringRef BinaryOperator::getOpcodeStr(Opcode Op) {
1819    switch (Op) {
1820    case BO_PtrMemD:   return ".*";
1821    case BO_PtrMemI:   return "->*";
1822    case BO_Mul:       return "*";
1823    case BO_Div:       return "/";
1824    case BO_Rem:       return "%";
1825    case BO_Add:       return "+";
1826    case BO_Sub:       return "-";
1827    case BO_Shl:       return "<<";
1828    case BO_Shr:       return ">>";
1829    case BO_LT:        return "<";
1830    case BO_GT:        return ">";
1831    case BO_LE:        return "<=";
1832    case BO_GE:        return ">=";
1833    case BO_EQ:        return "==";
1834    case BO_NE:        return "!=";
1835    case BO_And:       return "&";
1836    case BO_Xor:       return "^";
1837    case BO_Or:        return "|";
1838    case BO_LAnd:      return "&&";
1839    case BO_LOr:       return "||";
1840    case BO_Assign:    return "=";
1841    case BO_MulAssign: return "*=";
1842    case BO_DivAssign: return "/=";
1843    case BO_RemAssign: return "%=";
1844    case BO_AddAssign: return "+=";
1845    case BO_SubAssign: return "-=";
1846    case BO_ShlAssign: return "<<=";
1847    case BO_ShrAssign: return ">>=";
1848    case BO_AndAssign: return "&=";
1849    case BO_XorAssign: return "^=";
1850    case BO_OrAssign:  return "|=";
1851    case BO_Comma:     return ",";
1852    }
1853  
1854    llvm_unreachable("Invalid OpCode!");
1855  }
1856  
1857  BinaryOperatorKind
getOverloadedOpcode(OverloadedOperatorKind OO)1858  BinaryOperator::getOverloadedOpcode(OverloadedOperatorKind OO) {
1859    switch (OO) {
1860    default: llvm_unreachable("Not an overloadable binary operator");
1861    case OO_Plus: return BO_Add;
1862    case OO_Minus: return BO_Sub;
1863    case OO_Star: return BO_Mul;
1864    case OO_Slash: return BO_Div;
1865    case OO_Percent: return BO_Rem;
1866    case OO_Caret: return BO_Xor;
1867    case OO_Amp: return BO_And;
1868    case OO_Pipe: return BO_Or;
1869    case OO_Equal: return BO_Assign;
1870    case OO_Less: return BO_LT;
1871    case OO_Greater: return BO_GT;
1872    case OO_PlusEqual: return BO_AddAssign;
1873    case OO_MinusEqual: return BO_SubAssign;
1874    case OO_StarEqual: return BO_MulAssign;
1875    case OO_SlashEqual: return BO_DivAssign;
1876    case OO_PercentEqual: return BO_RemAssign;
1877    case OO_CaretEqual: return BO_XorAssign;
1878    case OO_AmpEqual: return BO_AndAssign;
1879    case OO_PipeEqual: return BO_OrAssign;
1880    case OO_LessLess: return BO_Shl;
1881    case OO_GreaterGreater: return BO_Shr;
1882    case OO_LessLessEqual: return BO_ShlAssign;
1883    case OO_GreaterGreaterEqual: return BO_ShrAssign;
1884    case OO_EqualEqual: return BO_EQ;
1885    case OO_ExclaimEqual: return BO_NE;
1886    case OO_LessEqual: return BO_LE;
1887    case OO_GreaterEqual: return BO_GE;
1888    case OO_AmpAmp: return BO_LAnd;
1889    case OO_PipePipe: return BO_LOr;
1890    case OO_Comma: return BO_Comma;
1891    case OO_ArrowStar: return BO_PtrMemI;
1892    }
1893  }
1894  
getOverloadedOperator(Opcode Opc)1895  OverloadedOperatorKind BinaryOperator::getOverloadedOperator(Opcode Opc) {
1896    static const OverloadedOperatorKind OverOps[] = {
1897      /* .* Cannot be overloaded */OO_None, OO_ArrowStar,
1898      OO_Star, OO_Slash, OO_Percent,
1899      OO_Plus, OO_Minus,
1900      OO_LessLess, OO_GreaterGreater,
1901      OO_Less, OO_Greater, OO_LessEqual, OO_GreaterEqual,
1902      OO_EqualEqual, OO_ExclaimEqual,
1903      OO_Amp,
1904      OO_Caret,
1905      OO_Pipe,
1906      OO_AmpAmp,
1907      OO_PipePipe,
1908      OO_Equal, OO_StarEqual,
1909      OO_SlashEqual, OO_PercentEqual,
1910      OO_PlusEqual, OO_MinusEqual,
1911      OO_LessLessEqual, OO_GreaterGreaterEqual,
1912      OO_AmpEqual, OO_CaretEqual,
1913      OO_PipeEqual,
1914      OO_Comma
1915    };
1916    return OverOps[Opc];
1917  }
1918  
InitListExpr(const ASTContext & C,SourceLocation lbraceloc,ArrayRef<Expr * > initExprs,SourceLocation rbraceloc)1919  InitListExpr::InitListExpr(const ASTContext &C, SourceLocation lbraceloc,
1920                             ArrayRef<Expr*> initExprs, SourceLocation rbraceloc)
1921    : Expr(InitListExprClass, QualType(), VK_RValue, OK_Ordinary, false, false,
1922           false, false),
1923      InitExprs(C, initExprs.size()),
1924      LBraceLoc(lbraceloc), RBraceLoc(rbraceloc), AltForm(nullptr, true)
1925  {
1926    sawArrayRangeDesignator(false);
1927    for (unsigned I = 0; I != initExprs.size(); ++I) {
1928      if (initExprs[I]->isTypeDependent())
1929        ExprBits.TypeDependent = true;
1930      if (initExprs[I]->isValueDependent())
1931        ExprBits.ValueDependent = true;
1932      if (initExprs[I]->isInstantiationDependent())
1933        ExprBits.InstantiationDependent = true;
1934      if (initExprs[I]->containsUnexpandedParameterPack())
1935        ExprBits.ContainsUnexpandedParameterPack = true;
1936    }
1937  
1938    InitExprs.insert(C, InitExprs.end(), initExprs.begin(), initExprs.end());
1939  }
1940  
reserveInits(const ASTContext & C,unsigned NumInits)1941  void InitListExpr::reserveInits(const ASTContext &C, unsigned NumInits) {
1942    if (NumInits > InitExprs.size())
1943      InitExprs.reserve(C, NumInits);
1944  }
1945  
resizeInits(const ASTContext & C,unsigned NumInits)1946  void InitListExpr::resizeInits(const ASTContext &C, unsigned NumInits) {
1947    InitExprs.resize(C, NumInits, nullptr);
1948  }
1949  
updateInit(const ASTContext & C,unsigned Init,Expr * expr)1950  Expr *InitListExpr::updateInit(const ASTContext &C, unsigned Init, Expr *expr) {
1951    if (Init >= InitExprs.size()) {
1952      InitExprs.insert(C, InitExprs.end(), Init - InitExprs.size() + 1, nullptr);
1953      setInit(Init, expr);
1954      return nullptr;
1955    }
1956  
1957    Expr *Result = cast_or_null<Expr>(InitExprs[Init]);
1958    setInit(Init, expr);
1959    return Result;
1960  }
1961  
setArrayFiller(Expr * filler)1962  void InitListExpr::setArrayFiller(Expr *filler) {
1963    assert(!hasArrayFiller() && "Filler already set!");
1964    ArrayFillerOrUnionFieldInit = filler;
1965    // Fill out any "holes" in the array due to designated initializers.
1966    Expr **inits = getInits();
1967    for (unsigned i = 0, e = getNumInits(); i != e; ++i)
1968      if (inits[i] == nullptr)
1969        inits[i] = filler;
1970  }
1971  
isStringLiteralInit() const1972  bool InitListExpr::isStringLiteralInit() const {
1973    if (getNumInits() != 1)
1974      return false;
1975    const ArrayType *AT = getType()->getAsArrayTypeUnsafe();
1976    if (!AT || !AT->getElementType()->isIntegerType())
1977      return false;
1978    // It is possible for getInit() to return null.
1979    const Expr *Init = getInit(0);
1980    if (!Init)
1981      return false;
1982    Init = Init->IgnoreParens();
1983    return isa<StringLiteral>(Init) || isa<ObjCEncodeExpr>(Init);
1984  }
1985  
getLocStart() const1986  SourceLocation InitListExpr::getLocStart() const {
1987    if (InitListExpr *SyntacticForm = getSyntacticForm())
1988      return SyntacticForm->getLocStart();
1989    SourceLocation Beg = LBraceLoc;
1990    if (Beg.isInvalid()) {
1991      // Find the first non-null initializer.
1992      for (InitExprsTy::const_iterator I = InitExprs.begin(),
1993                                       E = InitExprs.end();
1994        I != E; ++I) {
1995        if (Stmt *S = *I) {
1996          Beg = S->getLocStart();
1997          break;
1998        }
1999      }
2000    }
2001    return Beg;
2002  }
2003  
getLocEnd() const2004  SourceLocation InitListExpr::getLocEnd() const {
2005    if (InitListExpr *SyntacticForm = getSyntacticForm())
2006      return SyntacticForm->getLocEnd();
2007    SourceLocation End = RBraceLoc;
2008    if (End.isInvalid()) {
2009      // Find the first non-null initializer from the end.
2010      for (InitExprsTy::const_reverse_iterator I = InitExprs.rbegin(),
2011           E = InitExprs.rend();
2012           I != E; ++I) {
2013        if (Stmt *S = *I) {
2014          End = S->getLocEnd();
2015          break;
2016        }
2017      }
2018    }
2019    return End;
2020  }
2021  
2022  /// getFunctionType - Return the underlying function type for this block.
2023  ///
getFunctionType() const2024  const FunctionProtoType *BlockExpr::getFunctionType() const {
2025    // The block pointer is never sugared, but the function type might be.
2026    return cast<BlockPointerType>(getType())
2027             ->getPointeeType()->castAs<FunctionProtoType>();
2028  }
2029  
getCaretLocation() const2030  SourceLocation BlockExpr::getCaretLocation() const {
2031    return TheBlock->getCaretLocation();
2032  }
getBody() const2033  const Stmt *BlockExpr::getBody() const {
2034    return TheBlock->getBody();
2035  }
getBody()2036  Stmt *BlockExpr::getBody() {
2037    return TheBlock->getBody();
2038  }
2039  
2040  
2041  //===----------------------------------------------------------------------===//
2042  // Generic Expression Routines
2043  //===----------------------------------------------------------------------===//
2044  
2045  /// isUnusedResultAWarning - Return true if this immediate expression should
2046  /// be warned about if the result is unused.  If so, fill in Loc and Ranges
2047  /// with location to warn on and the source range[s] to report with the
2048  /// warning.
isUnusedResultAWarning(const Expr * & WarnE,SourceLocation & Loc,SourceRange & R1,SourceRange & R2,ASTContext & Ctx) const2049  bool Expr::isUnusedResultAWarning(const Expr *&WarnE, SourceLocation &Loc,
2050                                    SourceRange &R1, SourceRange &R2,
2051                                    ASTContext &Ctx) const {
2052    // Don't warn if the expr is type dependent. The type could end up
2053    // instantiating to void.
2054    if (isTypeDependent())
2055      return false;
2056  
2057    switch (getStmtClass()) {
2058    default:
2059      if (getType()->isVoidType())
2060        return false;
2061      WarnE = this;
2062      Loc = getExprLoc();
2063      R1 = getSourceRange();
2064      return true;
2065    case ParenExprClass:
2066      return cast<ParenExpr>(this)->getSubExpr()->
2067        isUnusedResultAWarning(WarnE, Loc, R1, R2, Ctx);
2068    case GenericSelectionExprClass:
2069      return cast<GenericSelectionExpr>(this)->getResultExpr()->
2070        isUnusedResultAWarning(WarnE, Loc, R1, R2, Ctx);
2071    case ChooseExprClass:
2072      return cast<ChooseExpr>(this)->getChosenSubExpr()->
2073        isUnusedResultAWarning(WarnE, Loc, R1, R2, Ctx);
2074    case UnaryOperatorClass: {
2075      const UnaryOperator *UO = cast<UnaryOperator>(this);
2076  
2077      switch (UO->getOpcode()) {
2078      case UO_Plus:
2079      case UO_Minus:
2080      case UO_AddrOf:
2081      case UO_Not:
2082      case UO_LNot:
2083      case UO_Deref:
2084        break;
2085      case UO_Coawait:
2086        // This is just the 'operator co_await' call inside the guts of a
2087        // dependent co_await call.
2088      case UO_PostInc:
2089      case UO_PostDec:
2090      case UO_PreInc:
2091      case UO_PreDec:                 // ++/--
2092        return false;  // Not a warning.
2093      case UO_Real:
2094      case UO_Imag:
2095        // accessing a piece of a volatile complex is a side-effect.
2096        if (Ctx.getCanonicalType(UO->getSubExpr()->getType())
2097            .isVolatileQualified())
2098          return false;
2099        break;
2100      case UO_Extension:
2101        return UO->getSubExpr()->isUnusedResultAWarning(WarnE, Loc, R1, R2, Ctx);
2102      }
2103      WarnE = this;
2104      Loc = UO->getOperatorLoc();
2105      R1 = UO->getSubExpr()->getSourceRange();
2106      return true;
2107    }
2108    case BinaryOperatorClass: {
2109      const BinaryOperator *BO = cast<BinaryOperator>(this);
2110      switch (BO->getOpcode()) {
2111        default:
2112          break;
2113        // Consider the RHS of comma for side effects. LHS was checked by
2114        // Sema::CheckCommaOperands.
2115        case BO_Comma:
2116          // ((foo = <blah>), 0) is an idiom for hiding the result (and
2117          // lvalue-ness) of an assignment written in a macro.
2118          if (IntegerLiteral *IE =
2119                dyn_cast<IntegerLiteral>(BO->getRHS()->IgnoreParens()))
2120            if (IE->getValue() == 0)
2121              return false;
2122          return BO->getRHS()->isUnusedResultAWarning(WarnE, Loc, R1, R2, Ctx);
2123        // Consider '||', '&&' to have side effects if the LHS or RHS does.
2124        case BO_LAnd:
2125        case BO_LOr:
2126          if (!BO->getLHS()->isUnusedResultAWarning(WarnE, Loc, R1, R2, Ctx) ||
2127              !BO->getRHS()->isUnusedResultAWarning(WarnE, Loc, R1, R2, Ctx))
2128            return false;
2129          break;
2130      }
2131      if (BO->isAssignmentOp())
2132        return false;
2133      WarnE = this;
2134      Loc = BO->getOperatorLoc();
2135      R1 = BO->getLHS()->getSourceRange();
2136      R2 = BO->getRHS()->getSourceRange();
2137      return true;
2138    }
2139    case CompoundAssignOperatorClass:
2140    case VAArgExprClass:
2141    case AtomicExprClass:
2142      return false;
2143  
2144    case ConditionalOperatorClass: {
2145      // If only one of the LHS or RHS is a warning, the operator might
2146      // be being used for control flow. Only warn if both the LHS and
2147      // RHS are warnings.
2148      const ConditionalOperator *Exp = cast<ConditionalOperator>(this);
2149      if (!Exp->getRHS()->isUnusedResultAWarning(WarnE, Loc, R1, R2, Ctx))
2150        return false;
2151      if (!Exp->getLHS())
2152        return true;
2153      return Exp->getLHS()->isUnusedResultAWarning(WarnE, Loc, R1, R2, Ctx);
2154    }
2155  
2156    case MemberExprClass:
2157      WarnE = this;
2158      Loc = cast<MemberExpr>(this)->getMemberLoc();
2159      R1 = SourceRange(Loc, Loc);
2160      R2 = cast<MemberExpr>(this)->getBase()->getSourceRange();
2161      return true;
2162  
2163    case ArraySubscriptExprClass:
2164      WarnE = this;
2165      Loc = cast<ArraySubscriptExpr>(this)->getRBracketLoc();
2166      R1 = cast<ArraySubscriptExpr>(this)->getLHS()->getSourceRange();
2167      R2 = cast<ArraySubscriptExpr>(this)->getRHS()->getSourceRange();
2168      return true;
2169  
2170    case CXXOperatorCallExprClass: {
2171      // Warn about operator ==,!=,<,>,<=, and >= even when user-defined operator
2172      // overloads as there is no reasonable way to define these such that they
2173      // have non-trivial, desirable side-effects. See the -Wunused-comparison
2174      // warning: operators == and != are commonly typo'ed, and so warning on them
2175      // provides additional value as well. If this list is updated,
2176      // DiagnoseUnusedComparison should be as well.
2177      const CXXOperatorCallExpr *Op = cast<CXXOperatorCallExpr>(this);
2178      switch (Op->getOperator()) {
2179      default:
2180        break;
2181      case OO_EqualEqual:
2182      case OO_ExclaimEqual:
2183      case OO_Less:
2184      case OO_Greater:
2185      case OO_GreaterEqual:
2186      case OO_LessEqual:
2187        if (Op->getCallReturnType(Ctx)->isReferenceType() ||
2188            Op->getCallReturnType(Ctx)->isVoidType())
2189          break;
2190        WarnE = this;
2191        Loc = Op->getOperatorLoc();
2192        R1 = Op->getSourceRange();
2193        return true;
2194      }
2195  
2196      // Fallthrough for generic call handling.
2197    }
2198    case CallExprClass:
2199    case CXXMemberCallExprClass:
2200    case UserDefinedLiteralClass: {
2201      // If this is a direct call, get the callee.
2202      const CallExpr *CE = cast<CallExpr>(this);
2203      if (const Decl *FD = CE->getCalleeDecl()) {
2204        const FunctionDecl *Func = dyn_cast<FunctionDecl>(FD);
2205        bool HasWarnUnusedResultAttr = Func ? Func->hasUnusedResultAttr()
2206                                            : FD->hasAttr<WarnUnusedResultAttr>();
2207  
2208        // If the callee has attribute pure, const, or warn_unused_result, warn
2209        // about it. void foo() { strlen("bar"); } should warn.
2210        //
2211        // Note: If new cases are added here, DiagnoseUnusedExprResult should be
2212        // updated to match for QoI.
2213        if (HasWarnUnusedResultAttr ||
2214            FD->hasAttr<PureAttr>() || FD->hasAttr<ConstAttr>()) {
2215          WarnE = this;
2216          Loc = CE->getCallee()->getLocStart();
2217          R1 = CE->getCallee()->getSourceRange();
2218  
2219          if (unsigned NumArgs = CE->getNumArgs())
2220            R2 = SourceRange(CE->getArg(0)->getLocStart(),
2221                             CE->getArg(NumArgs-1)->getLocEnd());
2222          return true;
2223        }
2224      }
2225      return false;
2226    }
2227  
2228    // If we don't know precisely what we're looking at, let's not warn.
2229    case UnresolvedLookupExprClass:
2230    case CXXUnresolvedConstructExprClass:
2231      return false;
2232  
2233    case CXXTemporaryObjectExprClass:
2234    case CXXConstructExprClass: {
2235      if (const CXXRecordDecl *Type = getType()->getAsCXXRecordDecl()) {
2236        if (Type->hasAttr<WarnUnusedAttr>()) {
2237          WarnE = this;
2238          Loc = getLocStart();
2239          R1 = getSourceRange();
2240          return true;
2241        }
2242      }
2243      return false;
2244    }
2245  
2246    case ObjCMessageExprClass: {
2247      const ObjCMessageExpr *ME = cast<ObjCMessageExpr>(this);
2248      if (Ctx.getLangOpts().ObjCAutoRefCount &&
2249          ME->isInstanceMessage() &&
2250          !ME->getType()->isVoidType() &&
2251          ME->getMethodFamily() == OMF_init) {
2252        WarnE = this;
2253        Loc = getExprLoc();
2254        R1 = ME->getSourceRange();
2255        return true;
2256      }
2257  
2258      if (const ObjCMethodDecl *MD = ME->getMethodDecl())
2259        if (MD->hasAttr<WarnUnusedResultAttr>()) {
2260          WarnE = this;
2261          Loc = getExprLoc();
2262          return true;
2263        }
2264  
2265      return false;
2266    }
2267  
2268    case ObjCPropertyRefExprClass:
2269      WarnE = this;
2270      Loc = getExprLoc();
2271      R1 = getSourceRange();
2272      return true;
2273  
2274    case PseudoObjectExprClass: {
2275      const PseudoObjectExpr *PO = cast<PseudoObjectExpr>(this);
2276  
2277      // Only complain about things that have the form of a getter.
2278      if (isa<UnaryOperator>(PO->getSyntacticForm()) ||
2279          isa<BinaryOperator>(PO->getSyntacticForm()))
2280        return false;
2281  
2282      WarnE = this;
2283      Loc = getExprLoc();
2284      R1 = getSourceRange();
2285      return true;
2286    }
2287  
2288    case StmtExprClass: {
2289      // Statement exprs don't logically have side effects themselves, but are
2290      // sometimes used in macros in ways that give them a type that is unused.
2291      // For example ({ blah; foo(); }) will end up with a type if foo has a type.
2292      // however, if the result of the stmt expr is dead, we don't want to emit a
2293      // warning.
2294      const CompoundStmt *CS = cast<StmtExpr>(this)->getSubStmt();
2295      if (!CS->body_empty()) {
2296        if (const Expr *E = dyn_cast<Expr>(CS->body_back()))
2297          return E->isUnusedResultAWarning(WarnE, Loc, R1, R2, Ctx);
2298        if (const LabelStmt *Label = dyn_cast<LabelStmt>(CS->body_back()))
2299          if (const Expr *E = dyn_cast<Expr>(Label->getSubStmt()))
2300            return E->isUnusedResultAWarning(WarnE, Loc, R1, R2, Ctx);
2301      }
2302  
2303      if (getType()->isVoidType())
2304        return false;
2305      WarnE = this;
2306      Loc = cast<StmtExpr>(this)->getLParenLoc();
2307      R1 = getSourceRange();
2308      return true;
2309    }
2310    case CXXFunctionalCastExprClass:
2311    case CStyleCastExprClass: {
2312      // Ignore an explicit cast to void unless the operand is a non-trivial
2313      // volatile lvalue.
2314      const CastExpr *CE = cast<CastExpr>(this);
2315      if (CE->getCastKind() == CK_ToVoid) {
2316        if (CE->getSubExpr()->isGLValue() &&
2317            CE->getSubExpr()->getType().isVolatileQualified()) {
2318          const DeclRefExpr *DRE =
2319              dyn_cast<DeclRefExpr>(CE->getSubExpr()->IgnoreParens());
2320          if (!(DRE && isa<VarDecl>(DRE->getDecl()) &&
2321                cast<VarDecl>(DRE->getDecl())->hasLocalStorage())) {
2322            return CE->getSubExpr()->isUnusedResultAWarning(WarnE, Loc,
2323                                                            R1, R2, Ctx);
2324          }
2325        }
2326        return false;
2327      }
2328  
2329      // If this is a cast to a constructor conversion, check the operand.
2330      // Otherwise, the result of the cast is unused.
2331      if (CE->getCastKind() == CK_ConstructorConversion)
2332        return CE->getSubExpr()->isUnusedResultAWarning(WarnE, Loc, R1, R2, Ctx);
2333  
2334      WarnE = this;
2335      if (const CXXFunctionalCastExpr *CXXCE =
2336              dyn_cast<CXXFunctionalCastExpr>(this)) {
2337        Loc = CXXCE->getLocStart();
2338        R1 = CXXCE->getSubExpr()->getSourceRange();
2339      } else {
2340        const CStyleCastExpr *CStyleCE = cast<CStyleCastExpr>(this);
2341        Loc = CStyleCE->getLParenLoc();
2342        R1 = CStyleCE->getSubExpr()->getSourceRange();
2343      }
2344      return true;
2345    }
2346    case ImplicitCastExprClass: {
2347      const CastExpr *ICE = cast<ImplicitCastExpr>(this);
2348  
2349      // lvalue-to-rvalue conversion on a volatile lvalue is a side-effect.
2350      if (ICE->getCastKind() == CK_LValueToRValue &&
2351          ICE->getSubExpr()->getType().isVolatileQualified())
2352        return false;
2353  
2354      return ICE->getSubExpr()->isUnusedResultAWarning(WarnE, Loc, R1, R2, Ctx);
2355    }
2356    case CXXDefaultArgExprClass:
2357      return (cast<CXXDefaultArgExpr>(this)
2358              ->getExpr()->isUnusedResultAWarning(WarnE, Loc, R1, R2, Ctx));
2359    case CXXDefaultInitExprClass:
2360      return (cast<CXXDefaultInitExpr>(this)
2361              ->getExpr()->isUnusedResultAWarning(WarnE, Loc, R1, R2, Ctx));
2362  
2363    case CXXNewExprClass:
2364      // FIXME: In theory, there might be new expressions that don't have side
2365      // effects (e.g. a placement new with an uninitialized POD).
2366    case CXXDeleteExprClass:
2367      return false;
2368    case CXXBindTemporaryExprClass:
2369      return (cast<CXXBindTemporaryExpr>(this)
2370              ->getSubExpr()->isUnusedResultAWarning(WarnE, Loc, R1, R2, Ctx));
2371    case ExprWithCleanupsClass:
2372      return (cast<ExprWithCleanups>(this)
2373              ->getSubExpr()->isUnusedResultAWarning(WarnE, Loc, R1, R2, Ctx));
2374    }
2375  }
2376  
2377  /// isOBJCGCCandidate - Check if an expression is objc gc'able.
2378  /// returns true, if it is; false otherwise.
isOBJCGCCandidate(ASTContext & Ctx) const2379  bool Expr::isOBJCGCCandidate(ASTContext &Ctx) const {
2380    const Expr *E = IgnoreParens();
2381    switch (E->getStmtClass()) {
2382    default:
2383      return false;
2384    case ObjCIvarRefExprClass:
2385      return true;
2386    case Expr::UnaryOperatorClass:
2387      return cast<UnaryOperator>(E)->getSubExpr()->isOBJCGCCandidate(Ctx);
2388    case ImplicitCastExprClass:
2389      return cast<ImplicitCastExpr>(E)->getSubExpr()->isOBJCGCCandidate(Ctx);
2390    case MaterializeTemporaryExprClass:
2391      return cast<MaterializeTemporaryExpr>(E)->GetTemporaryExpr()
2392                                                        ->isOBJCGCCandidate(Ctx);
2393    case CStyleCastExprClass:
2394      return cast<CStyleCastExpr>(E)->getSubExpr()->isOBJCGCCandidate(Ctx);
2395    case DeclRefExprClass: {
2396      const Decl *D = cast<DeclRefExpr>(E)->getDecl();
2397  
2398      if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
2399        if (VD->hasGlobalStorage())
2400          return true;
2401        QualType T = VD->getType();
2402        // dereferencing to a  pointer is always a gc'able candidate,
2403        // unless it is __weak.
2404        return T->isPointerType() &&
2405               (Ctx.getObjCGCAttrKind(T) != Qualifiers::Weak);
2406      }
2407      return false;
2408    }
2409    case MemberExprClass: {
2410      const MemberExpr *M = cast<MemberExpr>(E);
2411      return M->getBase()->isOBJCGCCandidate(Ctx);
2412    }
2413    case ArraySubscriptExprClass:
2414      return cast<ArraySubscriptExpr>(E)->getBase()->isOBJCGCCandidate(Ctx);
2415    }
2416  }
2417  
isBoundMemberFunction(ASTContext & Ctx) const2418  bool Expr::isBoundMemberFunction(ASTContext &Ctx) const {
2419    if (isTypeDependent())
2420      return false;
2421    return ClassifyLValue(Ctx) == Expr::LV_MemberFunction;
2422  }
2423  
findBoundMemberType(const Expr * expr)2424  QualType Expr::findBoundMemberType(const Expr *expr) {
2425    assert(expr->hasPlaceholderType(BuiltinType::BoundMember));
2426  
2427    // Bound member expressions are always one of these possibilities:
2428    //   x->m      x.m      x->*y      x.*y
2429    // (possibly parenthesized)
2430  
2431    expr = expr->IgnoreParens();
2432    if (const MemberExpr *mem = dyn_cast<MemberExpr>(expr)) {
2433      assert(isa<CXXMethodDecl>(mem->getMemberDecl()));
2434      return mem->getMemberDecl()->getType();
2435    }
2436  
2437    if (const BinaryOperator *op = dyn_cast<BinaryOperator>(expr)) {
2438      QualType type = op->getRHS()->getType()->castAs<MemberPointerType>()
2439                        ->getPointeeType();
2440      assert(type->isFunctionType());
2441      return type;
2442    }
2443  
2444    assert(isa<UnresolvedMemberExpr>(expr) || isa<CXXPseudoDestructorExpr>(expr));
2445    return QualType();
2446  }
2447  
IgnoreParens()2448  Expr* Expr::IgnoreParens() {
2449    Expr* E = this;
2450    while (true) {
2451      if (ParenExpr* P = dyn_cast<ParenExpr>(E)) {
2452        E = P->getSubExpr();
2453        continue;
2454      }
2455      if (UnaryOperator* P = dyn_cast<UnaryOperator>(E)) {
2456        if (P->getOpcode() == UO_Extension) {
2457          E = P->getSubExpr();
2458          continue;
2459        }
2460      }
2461      if (GenericSelectionExpr* P = dyn_cast<GenericSelectionExpr>(E)) {
2462        if (!P->isResultDependent()) {
2463          E = P->getResultExpr();
2464          continue;
2465        }
2466      }
2467      if (ChooseExpr* P = dyn_cast<ChooseExpr>(E)) {
2468        if (!P->isConditionDependent()) {
2469          E = P->getChosenSubExpr();
2470          continue;
2471        }
2472      }
2473      return E;
2474    }
2475  }
2476  
2477  /// IgnoreParenCasts - Ignore parentheses and casts.  Strip off any ParenExpr
2478  /// or CastExprs or ImplicitCastExprs, returning their operand.
IgnoreParenCasts()2479  Expr *Expr::IgnoreParenCasts() {
2480    Expr *E = this;
2481    while (true) {
2482      E = E->IgnoreParens();
2483      if (CastExpr *P = dyn_cast<CastExpr>(E)) {
2484        E = P->getSubExpr();
2485        continue;
2486      }
2487      if (MaterializeTemporaryExpr *Materialize
2488                                        = dyn_cast<MaterializeTemporaryExpr>(E)) {
2489        E = Materialize->GetTemporaryExpr();
2490        continue;
2491      }
2492      if (SubstNonTypeTemplateParmExpr *NTTP
2493                                    = dyn_cast<SubstNonTypeTemplateParmExpr>(E)) {
2494        E = NTTP->getReplacement();
2495        continue;
2496      }
2497      return E;
2498    }
2499  }
2500  
IgnoreCasts()2501  Expr *Expr::IgnoreCasts() {
2502    Expr *E = this;
2503    while (true) {
2504      if (CastExpr *P = dyn_cast<CastExpr>(E)) {
2505        E = P->getSubExpr();
2506        continue;
2507      }
2508      if (MaterializeTemporaryExpr *Materialize
2509          = dyn_cast<MaterializeTemporaryExpr>(E)) {
2510        E = Materialize->GetTemporaryExpr();
2511        continue;
2512      }
2513      if (SubstNonTypeTemplateParmExpr *NTTP
2514          = dyn_cast<SubstNonTypeTemplateParmExpr>(E)) {
2515        E = NTTP->getReplacement();
2516        continue;
2517      }
2518      return E;
2519    }
2520  }
2521  
2522  /// IgnoreParenLValueCasts - Ignore parentheses and lvalue-to-rvalue
2523  /// casts.  This is intended purely as a temporary workaround for code
2524  /// that hasn't yet been rewritten to do the right thing about those
2525  /// casts, and may disappear along with the last internal use.
IgnoreParenLValueCasts()2526  Expr *Expr::IgnoreParenLValueCasts() {
2527    Expr *E = this;
2528    while (true) {
2529      E = E->IgnoreParens();
2530      if (CastExpr *P = dyn_cast<CastExpr>(E)) {
2531        if (P->getCastKind() == CK_LValueToRValue) {
2532          E = P->getSubExpr();
2533          continue;
2534        }
2535      } else if (MaterializeTemporaryExpr *Materialize
2536                                        = dyn_cast<MaterializeTemporaryExpr>(E)) {
2537        E = Materialize->GetTemporaryExpr();
2538        continue;
2539      } else if (SubstNonTypeTemplateParmExpr *NTTP
2540                                    = dyn_cast<SubstNonTypeTemplateParmExpr>(E)) {
2541        E = NTTP->getReplacement();
2542        continue;
2543      }
2544      break;
2545    }
2546    return E;
2547  }
2548  
ignoreParenBaseCasts()2549  Expr *Expr::ignoreParenBaseCasts() {
2550    Expr *E = this;
2551    while (true) {
2552      E = E->IgnoreParens();
2553      if (CastExpr *CE = dyn_cast<CastExpr>(E)) {
2554        if (CE->getCastKind() == CK_DerivedToBase ||
2555            CE->getCastKind() == CK_UncheckedDerivedToBase ||
2556            CE->getCastKind() == CK_NoOp) {
2557          E = CE->getSubExpr();
2558          continue;
2559        }
2560      }
2561  
2562      return E;
2563    }
2564  }
2565  
IgnoreParenImpCasts()2566  Expr *Expr::IgnoreParenImpCasts() {
2567    Expr *E = this;
2568    while (true) {
2569      E = E->IgnoreParens();
2570      if (ImplicitCastExpr *P = dyn_cast<ImplicitCastExpr>(E)) {
2571        E = P->getSubExpr();
2572        continue;
2573      }
2574      if (MaterializeTemporaryExpr *Materialize
2575                                        = dyn_cast<MaterializeTemporaryExpr>(E)) {
2576        E = Materialize->GetTemporaryExpr();
2577        continue;
2578      }
2579      if (SubstNonTypeTemplateParmExpr *NTTP
2580                                    = dyn_cast<SubstNonTypeTemplateParmExpr>(E)) {
2581        E = NTTP->getReplacement();
2582        continue;
2583      }
2584      return E;
2585    }
2586  }
2587  
IgnoreConversionOperator()2588  Expr *Expr::IgnoreConversionOperator() {
2589    if (CXXMemberCallExpr *MCE = dyn_cast<CXXMemberCallExpr>(this)) {
2590      if (MCE->getMethodDecl() && isa<CXXConversionDecl>(MCE->getMethodDecl()))
2591        return MCE->getImplicitObjectArgument();
2592    }
2593    return this;
2594  }
2595  
2596  /// IgnoreParenNoopCasts - Ignore parentheses and casts that do not change the
2597  /// value (including ptr->int casts of the same size).  Strip off any
2598  /// ParenExpr or CastExprs, returning their operand.
IgnoreParenNoopCasts(ASTContext & Ctx)2599  Expr *Expr::IgnoreParenNoopCasts(ASTContext &Ctx) {
2600    Expr *E = this;
2601    while (true) {
2602      E = E->IgnoreParens();
2603  
2604      if (CastExpr *P = dyn_cast<CastExpr>(E)) {
2605        // We ignore integer <-> casts that are of the same width, ptr<->ptr and
2606        // ptr<->int casts of the same width.  We also ignore all identity casts.
2607        Expr *SE = P->getSubExpr();
2608  
2609        if (Ctx.hasSameUnqualifiedType(E->getType(), SE->getType())) {
2610          E = SE;
2611          continue;
2612        }
2613  
2614        if ((E->getType()->isPointerType() ||
2615             E->getType()->isIntegralType(Ctx)) &&
2616            (SE->getType()->isPointerType() ||
2617             SE->getType()->isIntegralType(Ctx)) &&
2618            Ctx.getTypeSize(E->getType()) == Ctx.getTypeSize(SE->getType())) {
2619          E = SE;
2620          continue;
2621        }
2622      }
2623  
2624      if (SubstNonTypeTemplateParmExpr *NTTP
2625                                    = dyn_cast<SubstNonTypeTemplateParmExpr>(E)) {
2626        E = NTTP->getReplacement();
2627        continue;
2628      }
2629  
2630      return E;
2631    }
2632  }
2633  
isDefaultArgument() const2634  bool Expr::isDefaultArgument() const {
2635    const Expr *E = this;
2636    if (const MaterializeTemporaryExpr *M = dyn_cast<MaterializeTemporaryExpr>(E))
2637      E = M->GetTemporaryExpr();
2638  
2639    while (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E))
2640      E = ICE->getSubExprAsWritten();
2641  
2642    return isa<CXXDefaultArgExpr>(E);
2643  }
2644  
2645  /// \brief Skip over any no-op casts and any temporary-binding
2646  /// expressions.
skipTemporaryBindingsNoOpCastsAndParens(const Expr * E)2647  static const Expr *skipTemporaryBindingsNoOpCastsAndParens(const Expr *E) {
2648    if (const MaterializeTemporaryExpr *M = dyn_cast<MaterializeTemporaryExpr>(E))
2649      E = M->GetTemporaryExpr();
2650  
2651    while (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E)) {
2652      if (ICE->getCastKind() == CK_NoOp)
2653        E = ICE->getSubExpr();
2654      else
2655        break;
2656    }
2657  
2658    while (const CXXBindTemporaryExpr *BE = dyn_cast<CXXBindTemporaryExpr>(E))
2659      E = BE->getSubExpr();
2660  
2661    while (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E)) {
2662      if (ICE->getCastKind() == CK_NoOp)
2663        E = ICE->getSubExpr();
2664      else
2665        break;
2666    }
2667  
2668    return E->IgnoreParens();
2669  }
2670  
2671  /// isTemporaryObject - Determines if this expression produces a
2672  /// temporary of the given class type.
isTemporaryObject(ASTContext & C,const CXXRecordDecl * TempTy) const2673  bool Expr::isTemporaryObject(ASTContext &C, const CXXRecordDecl *TempTy) const {
2674    if (!C.hasSameUnqualifiedType(getType(), C.getTypeDeclType(TempTy)))
2675      return false;
2676  
2677    const Expr *E = skipTemporaryBindingsNoOpCastsAndParens(this);
2678  
2679    // Temporaries are by definition pr-values of class type.
2680    if (!E->Classify(C).isPRValue()) {
2681      // In this context, property reference is a message call and is pr-value.
2682      if (!isa<ObjCPropertyRefExpr>(E))
2683        return false;
2684    }
2685  
2686    // Black-list a few cases which yield pr-values of class type that don't
2687    // refer to temporaries of that type:
2688  
2689    // - implicit derived-to-base conversions
2690    if (isa<ImplicitCastExpr>(E)) {
2691      switch (cast<ImplicitCastExpr>(E)->getCastKind()) {
2692      case CK_DerivedToBase:
2693      case CK_UncheckedDerivedToBase:
2694        return false;
2695      default:
2696        break;
2697      }
2698    }
2699  
2700    // - member expressions (all)
2701    if (isa<MemberExpr>(E))
2702      return false;
2703  
2704    if (const BinaryOperator *BO = dyn_cast<BinaryOperator>(E))
2705      if (BO->isPtrMemOp())
2706        return false;
2707  
2708    // - opaque values (all)
2709    if (isa<OpaqueValueExpr>(E))
2710      return false;
2711  
2712    return true;
2713  }
2714  
isImplicitCXXThis() const2715  bool Expr::isImplicitCXXThis() const {
2716    const Expr *E = this;
2717  
2718    // Strip away parentheses and casts we don't care about.
2719    while (true) {
2720      if (const ParenExpr *Paren = dyn_cast<ParenExpr>(E)) {
2721        E = Paren->getSubExpr();
2722        continue;
2723      }
2724  
2725      if (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E)) {
2726        if (ICE->getCastKind() == CK_NoOp ||
2727            ICE->getCastKind() == CK_LValueToRValue ||
2728            ICE->getCastKind() == CK_DerivedToBase ||
2729            ICE->getCastKind() == CK_UncheckedDerivedToBase) {
2730          E = ICE->getSubExpr();
2731          continue;
2732        }
2733      }
2734  
2735      if (const UnaryOperator* UnOp = dyn_cast<UnaryOperator>(E)) {
2736        if (UnOp->getOpcode() == UO_Extension) {
2737          E = UnOp->getSubExpr();
2738          continue;
2739        }
2740      }
2741  
2742      if (const MaterializeTemporaryExpr *M
2743                                        = dyn_cast<MaterializeTemporaryExpr>(E)) {
2744        E = M->GetTemporaryExpr();
2745        continue;
2746      }
2747  
2748      break;
2749    }
2750  
2751    if (const CXXThisExpr *This = dyn_cast<CXXThisExpr>(E))
2752      return This->isImplicit();
2753  
2754    return false;
2755  }
2756  
2757  /// hasAnyTypeDependentArguments - Determines if any of the expressions
2758  /// in Exprs is type-dependent.
hasAnyTypeDependentArguments(ArrayRef<Expr * > Exprs)2759  bool Expr::hasAnyTypeDependentArguments(ArrayRef<Expr *> Exprs) {
2760    for (unsigned I = 0; I < Exprs.size(); ++I)
2761      if (Exprs[I]->isTypeDependent())
2762        return true;
2763  
2764    return false;
2765  }
2766  
isConstantInitializer(ASTContext & Ctx,bool IsForRef,const Expr ** Culprit) const2767  bool Expr::isConstantInitializer(ASTContext &Ctx, bool IsForRef,
2768                                   const Expr **Culprit) const {
2769    // This function is attempting whether an expression is an initializer
2770    // which can be evaluated at compile-time. It very closely parallels
2771    // ConstExprEmitter in CGExprConstant.cpp; if they don't match, it
2772    // will lead to unexpected results.  Like ConstExprEmitter, it falls back
2773    // to isEvaluatable most of the time.
2774    //
2775    // If we ever capture reference-binding directly in the AST, we can
2776    // kill the second parameter.
2777  
2778    if (IsForRef) {
2779      EvalResult Result;
2780      if (EvaluateAsLValue(Result, Ctx) && !Result.HasSideEffects)
2781        return true;
2782      if (Culprit)
2783        *Culprit = this;
2784      return false;
2785    }
2786  
2787    switch (getStmtClass()) {
2788    default: break;
2789    case StringLiteralClass:
2790    case ObjCEncodeExprClass:
2791      return true;
2792    case CXXTemporaryObjectExprClass:
2793    case CXXConstructExprClass: {
2794      const CXXConstructExpr *CE = cast<CXXConstructExpr>(this);
2795  
2796      if (CE->getConstructor()->isTrivial() &&
2797          CE->getConstructor()->getParent()->hasTrivialDestructor()) {
2798        // Trivial default constructor
2799        if (!CE->getNumArgs()) return true;
2800  
2801        // Trivial copy constructor
2802        assert(CE->getNumArgs() == 1 && "trivial ctor with > 1 argument");
2803        return CE->getArg(0)->isConstantInitializer(Ctx, false, Culprit);
2804      }
2805  
2806      break;
2807    }
2808    case CompoundLiteralExprClass: {
2809      // This handles gcc's extension that allows global initializers like
2810      // "struct x {int x;} x = (struct x) {};".
2811      // FIXME: This accepts other cases it shouldn't!
2812      const Expr *Exp = cast<CompoundLiteralExpr>(this)->getInitializer();
2813      return Exp->isConstantInitializer(Ctx, false, Culprit);
2814    }
2815    case DesignatedInitUpdateExprClass: {
2816      const DesignatedInitUpdateExpr *DIUE = cast<DesignatedInitUpdateExpr>(this);
2817      return DIUE->getBase()->isConstantInitializer(Ctx, false, Culprit) &&
2818             DIUE->getUpdater()->isConstantInitializer(Ctx, false, Culprit);
2819    }
2820    case InitListExprClass: {
2821      const InitListExpr *ILE = cast<InitListExpr>(this);
2822      if (ILE->getType()->isArrayType()) {
2823        unsigned numInits = ILE->getNumInits();
2824        for (unsigned i = 0; i < numInits; i++) {
2825          if (!ILE->getInit(i)->isConstantInitializer(Ctx, false, Culprit))
2826            return false;
2827        }
2828        return true;
2829      }
2830  
2831      if (ILE->getType()->isRecordType()) {
2832        unsigned ElementNo = 0;
2833        RecordDecl *RD = ILE->getType()->getAs<RecordType>()->getDecl();
2834        for (const auto *Field : RD->fields()) {
2835          // If this is a union, skip all the fields that aren't being initialized.
2836          if (RD->isUnion() && ILE->getInitializedFieldInUnion() != Field)
2837            continue;
2838  
2839          // Don't emit anonymous bitfields, they just affect layout.
2840          if (Field->isUnnamedBitfield())
2841            continue;
2842  
2843          if (ElementNo < ILE->getNumInits()) {
2844            const Expr *Elt = ILE->getInit(ElementNo++);
2845            if (Field->isBitField()) {
2846              // Bitfields have to evaluate to an integer.
2847              llvm::APSInt ResultTmp;
2848              if (!Elt->EvaluateAsInt(ResultTmp, Ctx)) {
2849                if (Culprit)
2850                  *Culprit = Elt;
2851                return false;
2852              }
2853            } else {
2854              bool RefType = Field->getType()->isReferenceType();
2855              if (!Elt->isConstantInitializer(Ctx, RefType, Culprit))
2856                return false;
2857            }
2858          }
2859        }
2860        return true;
2861      }
2862  
2863      break;
2864    }
2865    case ImplicitValueInitExprClass:
2866    case NoInitExprClass:
2867      return true;
2868    case ParenExprClass:
2869      return cast<ParenExpr>(this)->getSubExpr()
2870        ->isConstantInitializer(Ctx, IsForRef, Culprit);
2871    case GenericSelectionExprClass:
2872      return cast<GenericSelectionExpr>(this)->getResultExpr()
2873        ->isConstantInitializer(Ctx, IsForRef, Culprit);
2874    case ChooseExprClass:
2875      if (cast<ChooseExpr>(this)->isConditionDependent()) {
2876        if (Culprit)
2877          *Culprit = this;
2878        return false;
2879      }
2880      return cast<ChooseExpr>(this)->getChosenSubExpr()
2881        ->isConstantInitializer(Ctx, IsForRef, Culprit);
2882    case UnaryOperatorClass: {
2883      const UnaryOperator* Exp = cast<UnaryOperator>(this);
2884      if (Exp->getOpcode() == UO_Extension)
2885        return Exp->getSubExpr()->isConstantInitializer(Ctx, false, Culprit);
2886      break;
2887    }
2888    case CXXFunctionalCastExprClass:
2889    case CXXStaticCastExprClass:
2890    case ImplicitCastExprClass:
2891    case CStyleCastExprClass:
2892    case ObjCBridgedCastExprClass:
2893    case CXXDynamicCastExprClass:
2894    case CXXReinterpretCastExprClass:
2895    case CXXConstCastExprClass: {
2896      const CastExpr *CE = cast<CastExpr>(this);
2897  
2898      // Handle misc casts we want to ignore.
2899      if (CE->getCastKind() == CK_NoOp ||
2900          CE->getCastKind() == CK_LValueToRValue ||
2901          CE->getCastKind() == CK_ToUnion ||
2902          CE->getCastKind() == CK_ConstructorConversion ||
2903          CE->getCastKind() == CK_NonAtomicToAtomic ||
2904          CE->getCastKind() == CK_AtomicToNonAtomic)
2905        return CE->getSubExpr()->isConstantInitializer(Ctx, false, Culprit);
2906  
2907      break;
2908    }
2909    case MaterializeTemporaryExprClass:
2910      return cast<MaterializeTemporaryExpr>(this)->GetTemporaryExpr()
2911        ->isConstantInitializer(Ctx, false, Culprit);
2912  
2913    case SubstNonTypeTemplateParmExprClass:
2914      return cast<SubstNonTypeTemplateParmExpr>(this)->getReplacement()
2915        ->isConstantInitializer(Ctx, false, Culprit);
2916    case CXXDefaultArgExprClass:
2917      return cast<CXXDefaultArgExpr>(this)->getExpr()
2918        ->isConstantInitializer(Ctx, false, Culprit);
2919    case CXXDefaultInitExprClass:
2920      return cast<CXXDefaultInitExpr>(this)->getExpr()
2921        ->isConstantInitializer(Ctx, false, Culprit);
2922    }
2923    // Allow certain forms of UB in constant initializers: signed integer
2924    // overflow and floating-point division by zero. We'll give a warning on
2925    // these, but they're common enough that we have to accept them.
2926    if (isEvaluatable(Ctx, SE_AllowUndefinedBehavior))
2927      return true;
2928    if (Culprit)
2929      *Culprit = this;
2930    return false;
2931  }
2932  
2933  namespace {
2934    /// \brief Look for any side effects within a Stmt.
2935    class SideEffectFinder : public ConstEvaluatedExprVisitor<SideEffectFinder> {
2936      typedef ConstEvaluatedExprVisitor<SideEffectFinder> Inherited;
2937      const bool IncludePossibleEffects;
2938      bool HasSideEffects;
2939  
2940    public:
SideEffectFinder(const ASTContext & Context,bool IncludePossible)2941      explicit SideEffectFinder(const ASTContext &Context, bool IncludePossible)
2942        : Inherited(Context),
2943          IncludePossibleEffects(IncludePossible), HasSideEffects(false) { }
2944  
hasSideEffects() const2945      bool hasSideEffects() const { return HasSideEffects; }
2946  
VisitExpr(const Expr * E)2947      void VisitExpr(const Expr *E) {
2948        if (!HasSideEffects &&
2949            E->HasSideEffects(Context, IncludePossibleEffects))
2950          HasSideEffects = true;
2951      }
2952    };
2953  }
2954  
HasSideEffects(const ASTContext & Ctx,bool IncludePossibleEffects) const2955  bool Expr::HasSideEffects(const ASTContext &Ctx,
2956                            bool IncludePossibleEffects) const {
2957    // In circumstances where we care about definite side effects instead of
2958    // potential side effects, we want to ignore expressions that are part of a
2959    // macro expansion as a potential side effect.
2960    if (!IncludePossibleEffects && getExprLoc().isMacroID())
2961      return false;
2962  
2963    if (isInstantiationDependent())
2964      return IncludePossibleEffects;
2965  
2966    switch (getStmtClass()) {
2967    case NoStmtClass:
2968    #define ABSTRACT_STMT(Type)
2969    #define STMT(Type, Base) case Type##Class:
2970    #define EXPR(Type, Base)
2971    #include "clang/AST/StmtNodes.inc"
2972      llvm_unreachable("unexpected Expr kind");
2973  
2974    case DependentScopeDeclRefExprClass:
2975    case CXXUnresolvedConstructExprClass:
2976    case CXXDependentScopeMemberExprClass:
2977    case UnresolvedLookupExprClass:
2978    case UnresolvedMemberExprClass:
2979    case PackExpansionExprClass:
2980    case SubstNonTypeTemplateParmPackExprClass:
2981    case FunctionParmPackExprClass:
2982    case TypoExprClass:
2983    case CXXFoldExprClass:
2984      llvm_unreachable("shouldn't see dependent / unresolved nodes here");
2985  
2986    case DeclRefExprClass:
2987    case ObjCIvarRefExprClass:
2988    case PredefinedExprClass:
2989    case IntegerLiteralClass:
2990    case FloatingLiteralClass:
2991    case ImaginaryLiteralClass:
2992    case StringLiteralClass:
2993    case CharacterLiteralClass:
2994    case OffsetOfExprClass:
2995    case ImplicitValueInitExprClass:
2996    case UnaryExprOrTypeTraitExprClass:
2997    case AddrLabelExprClass:
2998    case GNUNullExprClass:
2999    case NoInitExprClass:
3000    case CXXBoolLiteralExprClass:
3001    case CXXNullPtrLiteralExprClass:
3002    case CXXThisExprClass:
3003    case CXXScalarValueInitExprClass:
3004    case TypeTraitExprClass:
3005    case ArrayTypeTraitExprClass:
3006    case ExpressionTraitExprClass:
3007    case CXXNoexceptExprClass:
3008    case SizeOfPackExprClass:
3009    case ObjCStringLiteralClass:
3010    case ObjCEncodeExprClass:
3011    case ObjCBoolLiteralExprClass:
3012    case CXXUuidofExprClass:
3013    case OpaqueValueExprClass:
3014      // These never have a side-effect.
3015      return false;
3016  
3017    case CallExprClass:
3018    case CXXOperatorCallExprClass:
3019    case CXXMemberCallExprClass:
3020    case CUDAKernelCallExprClass:
3021    case UserDefinedLiteralClass: {
3022      // We don't know a call definitely has side effects, except for calls
3023      // to pure/const functions that definitely don't.
3024      // If the call itself is considered side-effect free, check the operands.
3025      const Decl *FD = cast<CallExpr>(this)->getCalleeDecl();
3026      bool IsPure = FD && (FD->hasAttr<ConstAttr>() || FD->hasAttr<PureAttr>());
3027      if (IsPure || !IncludePossibleEffects)
3028        break;
3029      return true;
3030    }
3031  
3032    case BlockExprClass:
3033    case CXXBindTemporaryExprClass:
3034      if (!IncludePossibleEffects)
3035        break;
3036      return true;
3037  
3038    case MSPropertyRefExprClass:
3039    case MSPropertySubscriptExprClass:
3040    case CompoundAssignOperatorClass:
3041    case VAArgExprClass:
3042    case AtomicExprClass:
3043    case CXXThrowExprClass:
3044    case CXXNewExprClass:
3045    case CXXDeleteExprClass:
3046    case ExprWithCleanupsClass:
3047    case CoawaitExprClass:
3048    case CoyieldExprClass:
3049      // These always have a side-effect.
3050      return true;
3051  
3052    case StmtExprClass: {
3053      // StmtExprs have a side-effect if any substatement does.
3054      SideEffectFinder Finder(Ctx, IncludePossibleEffects);
3055      Finder.Visit(cast<StmtExpr>(this)->getSubStmt());
3056      return Finder.hasSideEffects();
3057    }
3058  
3059    case ParenExprClass:
3060    case ArraySubscriptExprClass:
3061    case OMPArraySectionExprClass:
3062    case MemberExprClass:
3063    case ConditionalOperatorClass:
3064    case BinaryConditionalOperatorClass:
3065    case CompoundLiteralExprClass:
3066    case ExtVectorElementExprClass:
3067    case DesignatedInitExprClass:
3068    case DesignatedInitUpdateExprClass:
3069    case ParenListExprClass:
3070    case CXXPseudoDestructorExprClass:
3071    case CXXStdInitializerListExprClass:
3072    case SubstNonTypeTemplateParmExprClass:
3073    case MaterializeTemporaryExprClass:
3074    case ShuffleVectorExprClass:
3075    case ConvertVectorExprClass:
3076    case AsTypeExprClass:
3077      // These have a side-effect if any subexpression does.
3078      break;
3079  
3080    case UnaryOperatorClass:
3081      if (cast<UnaryOperator>(this)->isIncrementDecrementOp())
3082        return true;
3083      break;
3084  
3085    case BinaryOperatorClass:
3086      if (cast<BinaryOperator>(this)->isAssignmentOp())
3087        return true;
3088      break;
3089  
3090    case InitListExprClass:
3091      // FIXME: The children for an InitListExpr doesn't include the array filler.
3092      if (const Expr *E = cast<InitListExpr>(this)->getArrayFiller())
3093        if (E->HasSideEffects(Ctx, IncludePossibleEffects))
3094          return true;
3095      break;
3096  
3097    case GenericSelectionExprClass:
3098      return cast<GenericSelectionExpr>(this)->getResultExpr()->
3099          HasSideEffects(Ctx, IncludePossibleEffects);
3100  
3101    case ChooseExprClass:
3102      return cast<ChooseExpr>(this)->getChosenSubExpr()->HasSideEffects(
3103          Ctx, IncludePossibleEffects);
3104  
3105    case CXXDefaultArgExprClass:
3106      return cast<CXXDefaultArgExpr>(this)->getExpr()->HasSideEffects(
3107          Ctx, IncludePossibleEffects);
3108  
3109    case CXXDefaultInitExprClass: {
3110      const FieldDecl *FD = cast<CXXDefaultInitExpr>(this)->getField();
3111      if (const Expr *E = FD->getInClassInitializer())
3112        return E->HasSideEffects(Ctx, IncludePossibleEffects);
3113      // If we've not yet parsed the initializer, assume it has side-effects.
3114      return true;
3115    }
3116  
3117    case CXXDynamicCastExprClass: {
3118      // A dynamic_cast expression has side-effects if it can throw.
3119      const CXXDynamicCastExpr *DCE = cast<CXXDynamicCastExpr>(this);
3120      if (DCE->getTypeAsWritten()->isReferenceType() &&
3121          DCE->getCastKind() == CK_Dynamic)
3122        return true;
3123    } // Fall through.
3124    case ImplicitCastExprClass:
3125    case CStyleCastExprClass:
3126    case CXXStaticCastExprClass:
3127    case CXXReinterpretCastExprClass:
3128    case CXXConstCastExprClass:
3129    case CXXFunctionalCastExprClass: {
3130      // While volatile reads are side-effecting in both C and C++, we treat them
3131      // as having possible (not definite) side-effects. This allows idiomatic
3132      // code to behave without warning, such as sizeof(*v) for a volatile-
3133      // qualified pointer.
3134      if (!IncludePossibleEffects)
3135        break;
3136  
3137      const CastExpr *CE = cast<CastExpr>(this);
3138      if (CE->getCastKind() == CK_LValueToRValue &&
3139          CE->getSubExpr()->getType().isVolatileQualified())
3140        return true;
3141      break;
3142    }
3143  
3144    case CXXTypeidExprClass:
3145      // typeid might throw if its subexpression is potentially-evaluated, so has
3146      // side-effects in that case whether or not its subexpression does.
3147      return cast<CXXTypeidExpr>(this)->isPotentiallyEvaluated();
3148  
3149    case CXXConstructExprClass:
3150    case CXXTemporaryObjectExprClass: {
3151      const CXXConstructExpr *CE = cast<CXXConstructExpr>(this);
3152      if (!CE->getConstructor()->isTrivial() && IncludePossibleEffects)
3153        return true;
3154      // A trivial constructor does not add any side-effects of its own. Just look
3155      // at its arguments.
3156      break;
3157    }
3158  
3159    case LambdaExprClass: {
3160      const LambdaExpr *LE = cast<LambdaExpr>(this);
3161      for (LambdaExpr::capture_iterator I = LE->capture_begin(),
3162                                        E = LE->capture_end(); I != E; ++I)
3163        if (I->getCaptureKind() == LCK_ByCopy)
3164          // FIXME: Only has a side-effect if the variable is volatile or if
3165          // the copy would invoke a non-trivial copy constructor.
3166          return true;
3167      return false;
3168    }
3169  
3170    case PseudoObjectExprClass: {
3171      // Only look for side-effects in the semantic form, and look past
3172      // OpaqueValueExpr bindings in that form.
3173      const PseudoObjectExpr *PO = cast<PseudoObjectExpr>(this);
3174      for (PseudoObjectExpr::const_semantics_iterator I = PO->semantics_begin(),
3175                                                      E = PO->semantics_end();
3176           I != E; ++I) {
3177        const Expr *Subexpr = *I;
3178        if (const OpaqueValueExpr *OVE = dyn_cast<OpaqueValueExpr>(Subexpr))
3179          Subexpr = OVE->getSourceExpr();
3180        if (Subexpr->HasSideEffects(Ctx, IncludePossibleEffects))
3181          return true;
3182      }
3183      return false;
3184    }
3185  
3186    case ObjCBoxedExprClass:
3187    case ObjCArrayLiteralClass:
3188    case ObjCDictionaryLiteralClass:
3189    case ObjCSelectorExprClass:
3190    case ObjCProtocolExprClass:
3191    case ObjCIsaExprClass:
3192    case ObjCIndirectCopyRestoreExprClass:
3193    case ObjCSubscriptRefExprClass:
3194    case ObjCBridgedCastExprClass:
3195    case ObjCMessageExprClass:
3196    case ObjCPropertyRefExprClass:
3197    // FIXME: Classify these cases better.
3198      if (IncludePossibleEffects)
3199        return true;
3200      break;
3201    }
3202  
3203    // Recurse to children.
3204    for (const Stmt *SubStmt : children())
3205      if (SubStmt &&
3206          cast<Expr>(SubStmt)->HasSideEffects(Ctx, IncludePossibleEffects))
3207        return true;
3208  
3209    return false;
3210  }
3211  
3212  namespace {
3213    /// \brief Look for a call to a non-trivial function within an expression.
3214    class NonTrivialCallFinder : public ConstEvaluatedExprVisitor<NonTrivialCallFinder>
3215    {
3216      typedef ConstEvaluatedExprVisitor<NonTrivialCallFinder> Inherited;
3217  
3218      bool NonTrivial;
3219  
3220    public:
NonTrivialCallFinder(const ASTContext & Context)3221      explicit NonTrivialCallFinder(const ASTContext &Context)
3222        : Inherited(Context), NonTrivial(false) { }
3223  
hasNonTrivialCall() const3224      bool hasNonTrivialCall() const { return NonTrivial; }
3225  
VisitCallExpr(const CallExpr * E)3226      void VisitCallExpr(const CallExpr *E) {
3227        if (const CXXMethodDecl *Method
3228            = dyn_cast_or_null<const CXXMethodDecl>(E->getCalleeDecl())) {
3229          if (Method->isTrivial()) {
3230            // Recurse to children of the call.
3231            Inherited::VisitStmt(E);
3232            return;
3233          }
3234        }
3235  
3236        NonTrivial = true;
3237      }
3238  
VisitCXXConstructExpr(const CXXConstructExpr * E)3239      void VisitCXXConstructExpr(const CXXConstructExpr *E) {
3240        if (E->getConstructor()->isTrivial()) {
3241          // Recurse to children of the call.
3242          Inherited::VisitStmt(E);
3243          return;
3244        }
3245  
3246        NonTrivial = true;
3247      }
3248  
VisitCXXBindTemporaryExpr(const CXXBindTemporaryExpr * E)3249      void VisitCXXBindTemporaryExpr(const CXXBindTemporaryExpr *E) {
3250        if (E->getTemporary()->getDestructor()->isTrivial()) {
3251          Inherited::VisitStmt(E);
3252          return;
3253        }
3254  
3255        NonTrivial = true;
3256      }
3257    };
3258  }
3259  
hasNonTrivialCall(const ASTContext & Ctx) const3260  bool Expr::hasNonTrivialCall(const ASTContext &Ctx) const {
3261    NonTrivialCallFinder Finder(Ctx);
3262    Finder.Visit(this);
3263    return Finder.hasNonTrivialCall();
3264  }
3265  
3266  /// isNullPointerConstant - C99 6.3.2.3p3 - Return whether this is a null
3267  /// pointer constant or not, as well as the specific kind of constant detected.
3268  /// Null pointer constants can be integer constant expressions with the
3269  /// value zero, casts of zero to void*, nullptr (C++0X), or __null
3270  /// (a GNU extension).
3271  Expr::NullPointerConstantKind
isNullPointerConstant(ASTContext & Ctx,NullPointerConstantValueDependence NPC) const3272  Expr::isNullPointerConstant(ASTContext &Ctx,
3273                              NullPointerConstantValueDependence NPC) const {
3274    if (isValueDependent() &&
3275        (!Ctx.getLangOpts().CPlusPlus11 || Ctx.getLangOpts().MSVCCompat)) {
3276      switch (NPC) {
3277      case NPC_NeverValueDependent:
3278        llvm_unreachable("Unexpected value dependent expression!");
3279      case NPC_ValueDependentIsNull:
3280        if (isTypeDependent() || getType()->isIntegralType(Ctx))
3281          return NPCK_ZeroExpression;
3282        else
3283          return NPCK_NotNull;
3284  
3285      case NPC_ValueDependentIsNotNull:
3286        return NPCK_NotNull;
3287      }
3288    }
3289  
3290    // Strip off a cast to void*, if it exists. Except in C++.
3291    if (const ExplicitCastExpr *CE = dyn_cast<ExplicitCastExpr>(this)) {
3292      if (!Ctx.getLangOpts().CPlusPlus) {
3293        // Check that it is a cast to void*.
3294        if (const PointerType *PT = CE->getType()->getAs<PointerType>()) {
3295          QualType Pointee = PT->getPointeeType();
3296          Qualifiers Q = Pointee.getQualifiers();
3297          // In OpenCL v2.0 generic address space acts as a placeholder
3298          // and should be ignored.
3299          bool IsASValid = true;
3300          if (Ctx.getLangOpts().OpenCLVersion >= 200) {
3301            if (Pointee.getAddressSpace() == LangAS::opencl_generic)
3302              Q.removeAddressSpace();
3303            else
3304              IsASValid = false;
3305          }
3306  
3307          if (IsASValid && !Q.hasQualifiers() &&
3308              Pointee->isVoidType() &&                      // to void*
3309              CE->getSubExpr()->getType()->isIntegerType()) // from int.
3310            return CE->getSubExpr()->isNullPointerConstant(Ctx, NPC);
3311        }
3312      }
3313    } else if (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(this)) {
3314      // Ignore the ImplicitCastExpr type entirely.
3315      return ICE->getSubExpr()->isNullPointerConstant(Ctx, NPC);
3316    } else if (const ParenExpr *PE = dyn_cast<ParenExpr>(this)) {
3317      // Accept ((void*)0) as a null pointer constant, as many other
3318      // implementations do.
3319      return PE->getSubExpr()->isNullPointerConstant(Ctx, NPC);
3320    } else if (const GenericSelectionExpr *GE =
3321                 dyn_cast<GenericSelectionExpr>(this)) {
3322      if (GE->isResultDependent())
3323        return NPCK_NotNull;
3324      return GE->getResultExpr()->isNullPointerConstant(Ctx, NPC);
3325    } else if (const ChooseExpr *CE = dyn_cast<ChooseExpr>(this)) {
3326      if (CE->isConditionDependent())
3327        return NPCK_NotNull;
3328      return CE->getChosenSubExpr()->isNullPointerConstant(Ctx, NPC);
3329    } else if (const CXXDefaultArgExpr *DefaultArg
3330                 = dyn_cast<CXXDefaultArgExpr>(this)) {
3331      // See through default argument expressions.
3332      return DefaultArg->getExpr()->isNullPointerConstant(Ctx, NPC);
3333    } else if (const CXXDefaultInitExpr *DefaultInit
3334                 = dyn_cast<CXXDefaultInitExpr>(this)) {
3335      // See through default initializer expressions.
3336      return DefaultInit->getExpr()->isNullPointerConstant(Ctx, NPC);
3337    } else if (isa<GNUNullExpr>(this)) {
3338      // The GNU __null extension is always a null pointer constant.
3339      return NPCK_GNUNull;
3340    } else if (const MaterializeTemporaryExpr *M
3341                                     = dyn_cast<MaterializeTemporaryExpr>(this)) {
3342      return M->GetTemporaryExpr()->isNullPointerConstant(Ctx, NPC);
3343    } else if (const OpaqueValueExpr *OVE = dyn_cast<OpaqueValueExpr>(this)) {
3344      if (const Expr *Source = OVE->getSourceExpr())
3345        return Source->isNullPointerConstant(Ctx, NPC);
3346    }
3347  
3348    // C++11 nullptr_t is always a null pointer constant.
3349    if (getType()->isNullPtrType())
3350      return NPCK_CXX11_nullptr;
3351  
3352    if (const RecordType *UT = getType()->getAsUnionType())
3353      if (!Ctx.getLangOpts().CPlusPlus11 &&
3354          UT && UT->getDecl()->hasAttr<TransparentUnionAttr>())
3355        if (const CompoundLiteralExpr *CLE = dyn_cast<CompoundLiteralExpr>(this)){
3356          const Expr *InitExpr = CLE->getInitializer();
3357          if (const InitListExpr *ILE = dyn_cast<InitListExpr>(InitExpr))
3358            return ILE->getInit(0)->isNullPointerConstant(Ctx, NPC);
3359        }
3360    // This expression must be an integer type.
3361    if (!getType()->isIntegerType() ||
3362        (Ctx.getLangOpts().CPlusPlus && getType()->isEnumeralType()))
3363      return NPCK_NotNull;
3364  
3365    if (Ctx.getLangOpts().CPlusPlus11) {
3366      // C++11 [conv.ptr]p1: A null pointer constant is an integer literal with
3367      // value zero or a prvalue of type std::nullptr_t.
3368      // Microsoft mode permits C++98 rules reflecting MSVC behavior.
3369      const IntegerLiteral *Lit = dyn_cast<IntegerLiteral>(this);
3370      if (Lit && !Lit->getValue())
3371        return NPCK_ZeroLiteral;
3372      else if (!Ctx.getLangOpts().MSVCCompat || !isCXX98IntegralConstantExpr(Ctx))
3373        return NPCK_NotNull;
3374    } else {
3375      // If we have an integer constant expression, we need to *evaluate* it and
3376      // test for the value 0.
3377      if (!isIntegerConstantExpr(Ctx))
3378        return NPCK_NotNull;
3379    }
3380  
3381    if (EvaluateKnownConstInt(Ctx) != 0)
3382      return NPCK_NotNull;
3383  
3384    if (isa<IntegerLiteral>(this))
3385      return NPCK_ZeroLiteral;
3386    return NPCK_ZeroExpression;
3387  }
3388  
3389  /// \brief If this expression is an l-value for an Objective C
3390  /// property, find the underlying property reference expression.
getObjCProperty() const3391  const ObjCPropertyRefExpr *Expr::getObjCProperty() const {
3392    const Expr *E = this;
3393    while (true) {
3394      assert((E->getValueKind() == VK_LValue &&
3395              E->getObjectKind() == OK_ObjCProperty) &&
3396             "expression is not a property reference");
3397      E = E->IgnoreParenCasts();
3398      if (const BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) {
3399        if (BO->getOpcode() == BO_Comma) {
3400          E = BO->getRHS();
3401          continue;
3402        }
3403      }
3404  
3405      break;
3406    }
3407  
3408    return cast<ObjCPropertyRefExpr>(E);
3409  }
3410  
isObjCSelfExpr() const3411  bool Expr::isObjCSelfExpr() const {
3412    const Expr *E = IgnoreParenImpCasts();
3413  
3414    const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E);
3415    if (!DRE)
3416      return false;
3417  
3418    const ImplicitParamDecl *Param = dyn_cast<ImplicitParamDecl>(DRE->getDecl());
3419    if (!Param)
3420      return false;
3421  
3422    const ObjCMethodDecl *M = dyn_cast<ObjCMethodDecl>(Param->getDeclContext());
3423    if (!M)
3424      return false;
3425  
3426    return M->getSelfDecl() == Param;
3427  }
3428  
getSourceBitField()3429  FieldDecl *Expr::getSourceBitField() {
3430    Expr *E = this->IgnoreParens();
3431  
3432    while (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E)) {
3433      if (ICE->getCastKind() == CK_LValueToRValue ||
3434          (ICE->getValueKind() != VK_RValue && ICE->getCastKind() == CK_NoOp))
3435        E = ICE->getSubExpr()->IgnoreParens();
3436      else
3437        break;
3438    }
3439  
3440    if (MemberExpr *MemRef = dyn_cast<MemberExpr>(E))
3441      if (FieldDecl *Field = dyn_cast<FieldDecl>(MemRef->getMemberDecl()))
3442        if (Field->isBitField())
3443          return Field;
3444  
3445    if (ObjCIvarRefExpr *IvarRef = dyn_cast<ObjCIvarRefExpr>(E))
3446      if (FieldDecl *Ivar = dyn_cast<FieldDecl>(IvarRef->getDecl()))
3447        if (Ivar->isBitField())
3448          return Ivar;
3449  
3450    if (DeclRefExpr *DeclRef = dyn_cast<DeclRefExpr>(E))
3451      if (FieldDecl *Field = dyn_cast<FieldDecl>(DeclRef->getDecl()))
3452        if (Field->isBitField())
3453          return Field;
3454  
3455    if (BinaryOperator *BinOp = dyn_cast<BinaryOperator>(E)) {
3456      if (BinOp->isAssignmentOp() && BinOp->getLHS())
3457        return BinOp->getLHS()->getSourceBitField();
3458  
3459      if (BinOp->getOpcode() == BO_Comma && BinOp->getRHS())
3460        return BinOp->getRHS()->getSourceBitField();
3461    }
3462  
3463    if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(E))
3464      if (UnOp->isPrefix() && UnOp->isIncrementDecrementOp())
3465        return UnOp->getSubExpr()->getSourceBitField();
3466  
3467    return nullptr;
3468  }
3469  
refersToVectorElement() const3470  bool Expr::refersToVectorElement() const {
3471    const Expr *E = this->IgnoreParens();
3472  
3473    while (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E)) {
3474      if (ICE->getValueKind() != VK_RValue &&
3475          ICE->getCastKind() == CK_NoOp)
3476        E = ICE->getSubExpr()->IgnoreParens();
3477      else
3478        break;
3479    }
3480  
3481    if (const ArraySubscriptExpr *ASE = dyn_cast<ArraySubscriptExpr>(E))
3482      return ASE->getBase()->getType()->isVectorType();
3483  
3484    if (isa<ExtVectorElementExpr>(E))
3485      return true;
3486  
3487    return false;
3488  }
3489  
refersToGlobalRegisterVar() const3490  bool Expr::refersToGlobalRegisterVar() const {
3491    const Expr *E = this->IgnoreParenImpCasts();
3492  
3493    if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E))
3494      if (const auto *VD = dyn_cast<VarDecl>(DRE->getDecl()))
3495        if (VD->getStorageClass() == SC_Register &&
3496            VD->hasAttr<AsmLabelAttr>() && !VD->isLocalVarDecl())
3497          return true;
3498  
3499    return false;
3500  }
3501  
3502  /// isArrow - Return true if the base expression is a pointer to vector,
3503  /// return false if the base expression is a vector.
isArrow() const3504  bool ExtVectorElementExpr::isArrow() const {
3505    return getBase()->getType()->isPointerType();
3506  }
3507  
getNumElements() const3508  unsigned ExtVectorElementExpr::getNumElements() const {
3509    if (const VectorType *VT = getType()->getAs<VectorType>())
3510      return VT->getNumElements();
3511    return 1;
3512  }
3513  
3514  /// containsDuplicateElements - Return true if any element access is repeated.
containsDuplicateElements() const3515  bool ExtVectorElementExpr::containsDuplicateElements() const {
3516    // FIXME: Refactor this code to an accessor on the AST node which returns the
3517    // "type" of component access, and share with code below and in Sema.
3518    StringRef Comp = Accessor->getName();
3519  
3520    // Halving swizzles do not contain duplicate elements.
3521    if (Comp == "hi" || Comp == "lo" || Comp == "even" || Comp == "odd")
3522      return false;
3523  
3524    // Advance past s-char prefix on hex swizzles.
3525    if (Comp[0] == 's' || Comp[0] == 'S')
3526      Comp = Comp.substr(1);
3527  
3528    for (unsigned i = 0, e = Comp.size(); i != e; ++i)
3529      if (Comp.substr(i + 1).find(Comp[i]) != StringRef::npos)
3530          return true;
3531  
3532    return false;
3533  }
3534  
3535  /// getEncodedElementAccess - We encode the fields as a llvm ConstantArray.
getEncodedElementAccess(SmallVectorImpl<uint32_t> & Elts) const3536  void ExtVectorElementExpr::getEncodedElementAccess(
3537      SmallVectorImpl<uint32_t> &Elts) const {
3538    StringRef Comp = Accessor->getName();
3539    if (Comp[0] == 's' || Comp[0] == 'S')
3540      Comp = Comp.substr(1);
3541  
3542    bool isHi =   Comp == "hi";
3543    bool isLo =   Comp == "lo";
3544    bool isEven = Comp == "even";
3545    bool isOdd  = Comp == "odd";
3546  
3547    for (unsigned i = 0, e = getNumElements(); i != e; ++i) {
3548      uint64_t Index;
3549  
3550      if (isHi)
3551        Index = e + i;
3552      else if (isLo)
3553        Index = i;
3554      else if (isEven)
3555        Index = 2 * i;
3556      else if (isOdd)
3557        Index = 2 * i + 1;
3558      else
3559        Index = ExtVectorType::getAccessorIdx(Comp[i]);
3560  
3561      Elts.push_back(Index);
3562    }
3563  }
3564  
ShuffleVectorExpr(const ASTContext & C,ArrayRef<Expr * > args,QualType Type,SourceLocation BLoc,SourceLocation RP)3565  ShuffleVectorExpr::ShuffleVectorExpr(const ASTContext &C, ArrayRef<Expr*> args,
3566                                       QualType Type, SourceLocation BLoc,
3567                                       SourceLocation RP)
3568     : Expr(ShuffleVectorExprClass, Type, VK_RValue, OK_Ordinary,
3569            Type->isDependentType(), Type->isDependentType(),
3570            Type->isInstantiationDependentType(),
3571            Type->containsUnexpandedParameterPack()),
3572       BuiltinLoc(BLoc), RParenLoc(RP), NumExprs(args.size())
3573  {
3574    SubExprs = new (C) Stmt*[args.size()];
3575    for (unsigned i = 0; i != args.size(); i++) {
3576      if (args[i]->isTypeDependent())
3577        ExprBits.TypeDependent = true;
3578      if (args[i]->isValueDependent())
3579        ExprBits.ValueDependent = true;
3580      if (args[i]->isInstantiationDependent())
3581        ExprBits.InstantiationDependent = true;
3582      if (args[i]->containsUnexpandedParameterPack())
3583        ExprBits.ContainsUnexpandedParameterPack = true;
3584  
3585      SubExprs[i] = args[i];
3586    }
3587  }
3588  
setExprs(const ASTContext & C,ArrayRef<Expr * > Exprs)3589  void ShuffleVectorExpr::setExprs(const ASTContext &C, ArrayRef<Expr *> Exprs) {
3590    if (SubExprs) C.Deallocate(SubExprs);
3591  
3592    this->NumExprs = Exprs.size();
3593    SubExprs = new (C) Stmt*[NumExprs];
3594    memcpy(SubExprs, Exprs.data(), sizeof(Expr *) * Exprs.size());
3595  }
3596  
GenericSelectionExpr(const ASTContext & Context,SourceLocation GenericLoc,Expr * ControllingExpr,ArrayRef<TypeSourceInfo * > AssocTypes,ArrayRef<Expr * > AssocExprs,SourceLocation DefaultLoc,SourceLocation RParenLoc,bool ContainsUnexpandedParameterPack,unsigned ResultIndex)3597  GenericSelectionExpr::GenericSelectionExpr(const ASTContext &Context,
3598                                 SourceLocation GenericLoc, Expr *ControllingExpr,
3599                                 ArrayRef<TypeSourceInfo*> AssocTypes,
3600                                 ArrayRef<Expr*> AssocExprs,
3601                                 SourceLocation DefaultLoc,
3602                                 SourceLocation RParenLoc,
3603                                 bool ContainsUnexpandedParameterPack,
3604                                 unsigned ResultIndex)
3605    : Expr(GenericSelectionExprClass,
3606           AssocExprs[ResultIndex]->getType(),
3607           AssocExprs[ResultIndex]->getValueKind(),
3608           AssocExprs[ResultIndex]->getObjectKind(),
3609           AssocExprs[ResultIndex]->isTypeDependent(),
3610           AssocExprs[ResultIndex]->isValueDependent(),
3611           AssocExprs[ResultIndex]->isInstantiationDependent(),
3612           ContainsUnexpandedParameterPack),
3613      AssocTypes(new (Context) TypeSourceInfo*[AssocTypes.size()]),
3614      SubExprs(new (Context) Stmt*[END_EXPR+AssocExprs.size()]),
3615      NumAssocs(AssocExprs.size()), ResultIndex(ResultIndex),
3616      GenericLoc(GenericLoc), DefaultLoc(DefaultLoc), RParenLoc(RParenLoc) {
3617    SubExprs[CONTROLLING] = ControllingExpr;
3618    assert(AssocTypes.size() == AssocExprs.size());
3619    std::copy(AssocTypes.begin(), AssocTypes.end(), this->AssocTypes);
3620    std::copy(AssocExprs.begin(), AssocExprs.end(), SubExprs+END_EXPR);
3621  }
3622  
GenericSelectionExpr(const ASTContext & Context,SourceLocation GenericLoc,Expr * ControllingExpr,ArrayRef<TypeSourceInfo * > AssocTypes,ArrayRef<Expr * > AssocExprs,SourceLocation DefaultLoc,SourceLocation RParenLoc,bool ContainsUnexpandedParameterPack)3623  GenericSelectionExpr::GenericSelectionExpr(const ASTContext &Context,
3624                                 SourceLocation GenericLoc, Expr *ControllingExpr,
3625                                 ArrayRef<TypeSourceInfo*> AssocTypes,
3626                                 ArrayRef<Expr*> AssocExprs,
3627                                 SourceLocation DefaultLoc,
3628                                 SourceLocation RParenLoc,
3629                                 bool ContainsUnexpandedParameterPack)
3630    : Expr(GenericSelectionExprClass,
3631           Context.DependentTy,
3632           VK_RValue,
3633           OK_Ordinary,
3634           /*isTypeDependent=*/true,
3635           /*isValueDependent=*/true,
3636           /*isInstantiationDependent=*/true,
3637           ContainsUnexpandedParameterPack),
3638      AssocTypes(new (Context) TypeSourceInfo*[AssocTypes.size()]),
3639      SubExprs(new (Context) Stmt*[END_EXPR+AssocExprs.size()]),
3640      NumAssocs(AssocExprs.size()), ResultIndex(-1U), GenericLoc(GenericLoc),
3641      DefaultLoc(DefaultLoc), RParenLoc(RParenLoc) {
3642    SubExprs[CONTROLLING] = ControllingExpr;
3643    assert(AssocTypes.size() == AssocExprs.size());
3644    std::copy(AssocTypes.begin(), AssocTypes.end(), this->AssocTypes);
3645    std::copy(AssocExprs.begin(), AssocExprs.end(), SubExprs+END_EXPR);
3646  }
3647  
3648  //===----------------------------------------------------------------------===//
3649  //  DesignatedInitExpr
3650  //===----------------------------------------------------------------------===//
3651  
getFieldName() const3652  IdentifierInfo *DesignatedInitExpr::Designator::getFieldName() const {
3653    assert(Kind == FieldDesignator && "Only valid on a field designator");
3654    if (Field.NameOrField & 0x01)
3655      return reinterpret_cast<IdentifierInfo *>(Field.NameOrField&~0x01);
3656    else
3657      return getField()->getIdentifier();
3658  }
3659  
DesignatedInitExpr(const ASTContext & C,QualType Ty,unsigned NumDesignators,const Designator * Designators,SourceLocation EqualOrColonLoc,bool GNUSyntax,ArrayRef<Expr * > IndexExprs,Expr * Init)3660  DesignatedInitExpr::DesignatedInitExpr(const ASTContext &C, QualType Ty,
3661                                         unsigned NumDesignators,
3662                                         const Designator *Designators,
3663                                         SourceLocation EqualOrColonLoc,
3664                                         bool GNUSyntax,
3665                                         ArrayRef<Expr*> IndexExprs,
3666                                         Expr *Init)
3667    : Expr(DesignatedInitExprClass, Ty,
3668           Init->getValueKind(), Init->getObjectKind(),
3669           Init->isTypeDependent(), Init->isValueDependent(),
3670           Init->isInstantiationDependent(),
3671           Init->containsUnexpandedParameterPack()),
3672      EqualOrColonLoc(EqualOrColonLoc), GNUSyntax(GNUSyntax),
3673      NumDesignators(NumDesignators), NumSubExprs(IndexExprs.size() + 1) {
3674    this->Designators = new (C) Designator[NumDesignators];
3675  
3676    // Record the initializer itself.
3677    child_iterator Child = child_begin();
3678    *Child++ = Init;
3679  
3680    // Copy the designators and their subexpressions, computing
3681    // value-dependence along the way.
3682    unsigned IndexIdx = 0;
3683    for (unsigned I = 0; I != NumDesignators; ++I) {
3684      this->Designators[I] = Designators[I];
3685  
3686      if (this->Designators[I].isArrayDesignator()) {
3687        // Compute type- and value-dependence.
3688        Expr *Index = IndexExprs[IndexIdx];
3689        if (Index->isTypeDependent() || Index->isValueDependent())
3690          ExprBits.TypeDependent = ExprBits.ValueDependent = true;
3691        if (Index->isInstantiationDependent())
3692          ExprBits.InstantiationDependent = true;
3693        // Propagate unexpanded parameter packs.
3694        if (Index->containsUnexpandedParameterPack())
3695          ExprBits.ContainsUnexpandedParameterPack = true;
3696  
3697        // Copy the index expressions into permanent storage.
3698        *Child++ = IndexExprs[IndexIdx++];
3699      } else if (this->Designators[I].isArrayRangeDesignator()) {
3700        // Compute type- and value-dependence.
3701        Expr *Start = IndexExprs[IndexIdx];
3702        Expr *End = IndexExprs[IndexIdx + 1];
3703        if (Start->isTypeDependent() || Start->isValueDependent() ||
3704            End->isTypeDependent() || End->isValueDependent()) {
3705          ExprBits.TypeDependent = ExprBits.ValueDependent = true;
3706          ExprBits.InstantiationDependent = true;
3707        } else if (Start->isInstantiationDependent() ||
3708                   End->isInstantiationDependent()) {
3709          ExprBits.InstantiationDependent = true;
3710        }
3711  
3712        // Propagate unexpanded parameter packs.
3713        if (Start->containsUnexpandedParameterPack() ||
3714            End->containsUnexpandedParameterPack())
3715          ExprBits.ContainsUnexpandedParameterPack = true;
3716  
3717        // Copy the start/end expressions into permanent storage.
3718        *Child++ = IndexExprs[IndexIdx++];
3719        *Child++ = IndexExprs[IndexIdx++];
3720      }
3721    }
3722  
3723    assert(IndexIdx == IndexExprs.size() && "Wrong number of index expressions");
3724  }
3725  
3726  DesignatedInitExpr *
Create(const ASTContext & C,Designator * Designators,unsigned NumDesignators,ArrayRef<Expr * > IndexExprs,SourceLocation ColonOrEqualLoc,bool UsesColonSyntax,Expr * Init)3727  DesignatedInitExpr::Create(const ASTContext &C, Designator *Designators,
3728                             unsigned NumDesignators,
3729                             ArrayRef<Expr*> IndexExprs,
3730                             SourceLocation ColonOrEqualLoc,
3731                             bool UsesColonSyntax, Expr *Init) {
3732    void *Mem = C.Allocate(sizeof(DesignatedInitExpr) +
3733                               sizeof(Stmt *) * (IndexExprs.size() + 1),
3734                           llvm::alignOf<DesignatedInitExpr>());
3735    return new (Mem) DesignatedInitExpr(C, C.VoidTy, NumDesignators, Designators,
3736                                        ColonOrEqualLoc, UsesColonSyntax,
3737                                        IndexExprs, Init);
3738  }
3739  
CreateEmpty(const ASTContext & C,unsigned NumIndexExprs)3740  DesignatedInitExpr *DesignatedInitExpr::CreateEmpty(const ASTContext &C,
3741                                                      unsigned NumIndexExprs) {
3742    void *Mem = C.Allocate(sizeof(DesignatedInitExpr) +
3743                           sizeof(Stmt *) * (NumIndexExprs + 1), 8);
3744    return new (Mem) DesignatedInitExpr(NumIndexExprs + 1);
3745  }
3746  
setDesignators(const ASTContext & C,const Designator * Desigs,unsigned NumDesigs)3747  void DesignatedInitExpr::setDesignators(const ASTContext &C,
3748                                          const Designator *Desigs,
3749                                          unsigned NumDesigs) {
3750    Designators = new (C) Designator[NumDesigs];
3751    NumDesignators = NumDesigs;
3752    for (unsigned I = 0; I != NumDesigs; ++I)
3753      Designators[I] = Desigs[I];
3754  }
3755  
getDesignatorsSourceRange() const3756  SourceRange DesignatedInitExpr::getDesignatorsSourceRange() const {
3757    DesignatedInitExpr *DIE = const_cast<DesignatedInitExpr*>(this);
3758    if (size() == 1)
3759      return DIE->getDesignator(0)->getSourceRange();
3760    return SourceRange(DIE->getDesignator(0)->getLocStart(),
3761                       DIE->getDesignator(size()-1)->getLocEnd());
3762  }
3763  
getLocStart() const3764  SourceLocation DesignatedInitExpr::getLocStart() const {
3765    SourceLocation StartLoc;
3766    Designator &First =
3767      *const_cast<DesignatedInitExpr*>(this)->designators_begin();
3768    if (First.isFieldDesignator()) {
3769      if (GNUSyntax)
3770        StartLoc = SourceLocation::getFromRawEncoding(First.Field.FieldLoc);
3771      else
3772        StartLoc = SourceLocation::getFromRawEncoding(First.Field.DotLoc);
3773    } else
3774      StartLoc =
3775        SourceLocation::getFromRawEncoding(First.ArrayOrRange.LBracketLoc);
3776    return StartLoc;
3777  }
3778  
getLocEnd() const3779  SourceLocation DesignatedInitExpr::getLocEnd() const {
3780    return getInit()->getLocEnd();
3781  }
3782  
getArrayIndex(const Designator & D) const3783  Expr *DesignatedInitExpr::getArrayIndex(const Designator& D) const {
3784    assert(D.Kind == Designator::ArrayDesignator && "Requires array designator");
3785    Stmt *const *SubExprs = reinterpret_cast<Stmt *const *>(this + 1);
3786    return cast<Expr>(*(SubExprs + D.ArrayOrRange.Index + 1));
3787  }
3788  
getArrayRangeStart(const Designator & D) const3789  Expr *DesignatedInitExpr::getArrayRangeStart(const Designator &D) const {
3790    assert(D.Kind == Designator::ArrayRangeDesignator &&
3791           "Requires array range designator");
3792    Stmt *const *SubExprs = reinterpret_cast<Stmt *const *>(this + 1);
3793    return cast<Expr>(*(SubExprs + D.ArrayOrRange.Index + 1));
3794  }
3795  
getArrayRangeEnd(const Designator & D) const3796  Expr *DesignatedInitExpr::getArrayRangeEnd(const Designator &D) const {
3797    assert(D.Kind == Designator::ArrayRangeDesignator &&
3798           "Requires array range designator");
3799    Stmt *const *SubExprs = reinterpret_cast<Stmt *const *>(this + 1);
3800    return cast<Expr>(*(SubExprs + D.ArrayOrRange.Index + 2));
3801  }
3802  
3803  /// \brief Replaces the designator at index @p Idx with the series
3804  /// of designators in [First, Last).
ExpandDesignator(const ASTContext & C,unsigned Idx,const Designator * First,const Designator * Last)3805  void DesignatedInitExpr::ExpandDesignator(const ASTContext &C, unsigned Idx,
3806                                            const Designator *First,
3807                                            const Designator *Last) {
3808    unsigned NumNewDesignators = Last - First;
3809    if (NumNewDesignators == 0) {
3810      std::copy_backward(Designators + Idx + 1,
3811                         Designators + NumDesignators,
3812                         Designators + Idx);
3813      --NumNewDesignators;
3814      return;
3815    } else if (NumNewDesignators == 1) {
3816      Designators[Idx] = *First;
3817      return;
3818    }
3819  
3820    Designator *NewDesignators
3821      = new (C) Designator[NumDesignators - 1 + NumNewDesignators];
3822    std::copy(Designators, Designators + Idx, NewDesignators);
3823    std::copy(First, Last, NewDesignators + Idx);
3824    std::copy(Designators + Idx + 1, Designators + NumDesignators,
3825              NewDesignators + Idx + NumNewDesignators);
3826    Designators = NewDesignators;
3827    NumDesignators = NumDesignators - 1 + NumNewDesignators;
3828  }
3829  
DesignatedInitUpdateExpr(const ASTContext & C,SourceLocation lBraceLoc,Expr * baseExpr,SourceLocation rBraceLoc)3830  DesignatedInitUpdateExpr::DesignatedInitUpdateExpr(const ASTContext &C,
3831      SourceLocation lBraceLoc, Expr *baseExpr, SourceLocation rBraceLoc)
3832    : Expr(DesignatedInitUpdateExprClass, baseExpr->getType(), VK_RValue,
3833           OK_Ordinary, false, false, false, false) {
3834    BaseAndUpdaterExprs[0] = baseExpr;
3835  
3836    InitListExpr *ILE = new (C) InitListExpr(C, lBraceLoc, None, rBraceLoc);
3837    ILE->setType(baseExpr->getType());
3838    BaseAndUpdaterExprs[1] = ILE;
3839  }
3840  
getLocStart() const3841  SourceLocation DesignatedInitUpdateExpr::getLocStart() const {
3842    return getBase()->getLocStart();
3843  }
3844  
getLocEnd() const3845  SourceLocation DesignatedInitUpdateExpr::getLocEnd() const {
3846    return getBase()->getLocEnd();
3847  }
3848  
ParenListExpr(const ASTContext & C,SourceLocation lparenloc,ArrayRef<Expr * > exprs,SourceLocation rparenloc)3849  ParenListExpr::ParenListExpr(const ASTContext& C, SourceLocation lparenloc,
3850                               ArrayRef<Expr*> exprs,
3851                               SourceLocation rparenloc)
3852    : Expr(ParenListExprClass, QualType(), VK_RValue, OK_Ordinary,
3853           false, false, false, false),
3854      NumExprs(exprs.size()), LParenLoc(lparenloc), RParenLoc(rparenloc) {
3855    Exprs = new (C) Stmt*[exprs.size()];
3856    for (unsigned i = 0; i != exprs.size(); ++i) {
3857      if (exprs[i]->isTypeDependent())
3858        ExprBits.TypeDependent = true;
3859      if (exprs[i]->isValueDependent())
3860        ExprBits.ValueDependent = true;
3861      if (exprs[i]->isInstantiationDependent())
3862        ExprBits.InstantiationDependent = true;
3863      if (exprs[i]->containsUnexpandedParameterPack())
3864        ExprBits.ContainsUnexpandedParameterPack = true;
3865  
3866      Exprs[i] = exprs[i];
3867    }
3868  }
3869  
findInCopyConstruct(const Expr * e)3870  const OpaqueValueExpr *OpaqueValueExpr::findInCopyConstruct(const Expr *e) {
3871    if (const ExprWithCleanups *ewc = dyn_cast<ExprWithCleanups>(e))
3872      e = ewc->getSubExpr();
3873    if (const MaterializeTemporaryExpr *m = dyn_cast<MaterializeTemporaryExpr>(e))
3874      e = m->GetTemporaryExpr();
3875    e = cast<CXXConstructExpr>(e)->getArg(0);
3876    while (const ImplicitCastExpr *ice = dyn_cast<ImplicitCastExpr>(e))
3877      e = ice->getSubExpr();
3878    return cast<OpaqueValueExpr>(e);
3879  }
3880  
Create(const ASTContext & Context,EmptyShell sh,unsigned numSemanticExprs)3881  PseudoObjectExpr *PseudoObjectExpr::Create(const ASTContext &Context,
3882                                             EmptyShell sh,
3883                                             unsigned numSemanticExprs) {
3884    void *buffer = Context.Allocate(sizeof(PseudoObjectExpr) +
3885                                      (1 + numSemanticExprs) * sizeof(Expr*),
3886                                    llvm::alignOf<PseudoObjectExpr>());
3887    return new(buffer) PseudoObjectExpr(sh, numSemanticExprs);
3888  }
3889  
PseudoObjectExpr(EmptyShell shell,unsigned numSemanticExprs)3890  PseudoObjectExpr::PseudoObjectExpr(EmptyShell shell, unsigned numSemanticExprs)
3891    : Expr(PseudoObjectExprClass, shell) {
3892    PseudoObjectExprBits.NumSubExprs = numSemanticExprs + 1;
3893  }
3894  
Create(const ASTContext & C,Expr * syntax,ArrayRef<Expr * > semantics,unsigned resultIndex)3895  PseudoObjectExpr *PseudoObjectExpr::Create(const ASTContext &C, Expr *syntax,
3896                                             ArrayRef<Expr*> semantics,
3897                                             unsigned resultIndex) {
3898    assert(syntax && "no syntactic expression!");
3899    assert(semantics.size() && "no semantic expressions!");
3900  
3901    QualType type;
3902    ExprValueKind VK;
3903    if (resultIndex == NoResult) {
3904      type = C.VoidTy;
3905      VK = VK_RValue;
3906    } else {
3907      assert(resultIndex < semantics.size());
3908      type = semantics[resultIndex]->getType();
3909      VK = semantics[resultIndex]->getValueKind();
3910      assert(semantics[resultIndex]->getObjectKind() == OK_Ordinary);
3911    }
3912  
3913    void *buffer = C.Allocate(sizeof(PseudoObjectExpr) +
3914                                (1 + semantics.size()) * sizeof(Expr*),
3915                              llvm::alignOf<PseudoObjectExpr>());
3916    return new(buffer) PseudoObjectExpr(type, VK, syntax, semantics,
3917                                        resultIndex);
3918  }
3919  
PseudoObjectExpr(QualType type,ExprValueKind VK,Expr * syntax,ArrayRef<Expr * > semantics,unsigned resultIndex)3920  PseudoObjectExpr::PseudoObjectExpr(QualType type, ExprValueKind VK,
3921                                     Expr *syntax, ArrayRef<Expr*> semantics,
3922                                     unsigned resultIndex)
3923    : Expr(PseudoObjectExprClass, type, VK, OK_Ordinary,
3924           /*filled in at end of ctor*/ false, false, false, false) {
3925    PseudoObjectExprBits.NumSubExprs = semantics.size() + 1;
3926    PseudoObjectExprBits.ResultIndex = resultIndex + 1;
3927  
3928    for (unsigned i = 0, e = semantics.size() + 1; i != e; ++i) {
3929      Expr *E = (i == 0 ? syntax : semantics[i-1]);
3930      getSubExprsBuffer()[i] = E;
3931  
3932      if (E->isTypeDependent())
3933        ExprBits.TypeDependent = true;
3934      if (E->isValueDependent())
3935        ExprBits.ValueDependent = true;
3936      if (E->isInstantiationDependent())
3937        ExprBits.InstantiationDependent = true;
3938      if (E->containsUnexpandedParameterPack())
3939        ExprBits.ContainsUnexpandedParameterPack = true;
3940  
3941      if (isa<OpaqueValueExpr>(E))
3942        assert(cast<OpaqueValueExpr>(E)->getSourceExpr() != nullptr &&
3943               "opaque-value semantic expressions for pseudo-object "
3944               "operations must have sources");
3945    }
3946  }
3947  
3948  //===----------------------------------------------------------------------===//
3949  //  Child Iterators for iterating over subexpressions/substatements
3950  //===----------------------------------------------------------------------===//
3951  
3952  // UnaryExprOrTypeTraitExpr
children()3953  Stmt::child_range UnaryExprOrTypeTraitExpr::children() {
3954    // If this is of a type and the type is a VLA type (and not a typedef), the
3955    // size expression of the VLA needs to be treated as an executable expression.
3956    // Why isn't this weirdness documented better in StmtIterator?
3957    if (isArgumentType()) {
3958      if (const VariableArrayType* T = dyn_cast<VariableArrayType>(
3959                                     getArgumentType().getTypePtr()))
3960        return child_range(child_iterator(T), child_iterator());
3961      return child_range(child_iterator(), child_iterator());
3962    }
3963    return child_range(&Argument.Ex, &Argument.Ex + 1);
3964  }
3965  
AtomicExpr(SourceLocation BLoc,ArrayRef<Expr * > args,QualType t,AtomicOp op,SourceLocation RP)3966  AtomicExpr::AtomicExpr(SourceLocation BLoc, ArrayRef<Expr*> args,
3967                         QualType t, AtomicOp op, SourceLocation RP)
3968    : Expr(AtomicExprClass, t, VK_RValue, OK_Ordinary,
3969           false, false, false, false),
3970      NumSubExprs(args.size()), BuiltinLoc(BLoc), RParenLoc(RP), Op(op)
3971  {
3972    assert(args.size() == getNumSubExprs(op) && "wrong number of subexpressions");
3973    for (unsigned i = 0; i != args.size(); i++) {
3974      if (args[i]->isTypeDependent())
3975        ExprBits.TypeDependent = true;
3976      if (args[i]->isValueDependent())
3977        ExprBits.ValueDependent = true;
3978      if (args[i]->isInstantiationDependent())
3979        ExprBits.InstantiationDependent = true;
3980      if (args[i]->containsUnexpandedParameterPack())
3981        ExprBits.ContainsUnexpandedParameterPack = true;
3982  
3983      SubExprs[i] = args[i];
3984    }
3985  }
3986  
getNumSubExprs(AtomicOp Op)3987  unsigned AtomicExpr::getNumSubExprs(AtomicOp Op) {
3988    switch (Op) {
3989    case AO__c11_atomic_init:
3990    case AO__c11_atomic_load:
3991    case AO__atomic_load_n:
3992      return 2;
3993  
3994    case AO__c11_atomic_store:
3995    case AO__c11_atomic_exchange:
3996    case AO__atomic_load:
3997    case AO__atomic_store:
3998    case AO__atomic_store_n:
3999    case AO__atomic_exchange_n:
4000    case AO__c11_atomic_fetch_add:
4001    case AO__c11_atomic_fetch_sub:
4002    case AO__c11_atomic_fetch_and:
4003    case AO__c11_atomic_fetch_or:
4004    case AO__c11_atomic_fetch_xor:
4005    case AO__atomic_fetch_add:
4006    case AO__atomic_fetch_sub:
4007    case AO__atomic_fetch_and:
4008    case AO__atomic_fetch_or:
4009    case AO__atomic_fetch_xor:
4010    case AO__atomic_fetch_nand:
4011    case AO__atomic_add_fetch:
4012    case AO__atomic_sub_fetch:
4013    case AO__atomic_and_fetch:
4014    case AO__atomic_or_fetch:
4015    case AO__atomic_xor_fetch:
4016    case AO__atomic_nand_fetch:
4017      return 3;
4018  
4019    case AO__atomic_exchange:
4020      return 4;
4021  
4022    case AO__c11_atomic_compare_exchange_strong:
4023    case AO__c11_atomic_compare_exchange_weak:
4024      return 5;
4025  
4026    case AO__atomic_compare_exchange:
4027    case AO__atomic_compare_exchange_n:
4028      return 6;
4029    }
4030    llvm_unreachable("unknown atomic op");
4031  }
4032  
getBaseOriginalType(Expr * Base)4033  QualType OMPArraySectionExpr::getBaseOriginalType(Expr *Base) {
4034    unsigned ArraySectionCount = 0;
4035    while (auto *OASE = dyn_cast<OMPArraySectionExpr>(Base->IgnoreParens())) {
4036      Base = OASE->getBase();
4037      ++ArraySectionCount;
4038    }
4039    while (auto *ASE = dyn_cast<ArraySubscriptExpr>(Base->IgnoreParens())) {
4040      Base = ASE->getBase();
4041      ++ArraySectionCount;
4042    }
4043    auto OriginalTy = Base->getType();
4044    if (auto *DRE = dyn_cast<DeclRefExpr>(Base))
4045      if (auto *PVD = dyn_cast<ParmVarDecl>(DRE->getDecl()))
4046        OriginalTy = PVD->getOriginalType().getNonReferenceType();
4047  
4048    for (unsigned Cnt = 0; Cnt < ArraySectionCount; ++Cnt) {
4049      if (OriginalTy->isAnyPointerType())
4050        OriginalTy = OriginalTy->getPointeeType();
4051      else {
4052        assert (OriginalTy->isArrayType());
4053        OriginalTy = OriginalTy->castAsArrayTypeUnsafe()->getElementType();
4054      }
4055    }
4056    return OriginalTy;
4057  }
4058  
4059