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external
clang
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AST
Expr.cpp
//===--- Expr.cpp - Expression AST Node Implementation --------------------===// // // The LLVM Compiler Infrastructure // // This file is distributed under the University of Illinois Open Source // License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// // // This file implements the Expr class and subclasses. // //===----------------------------------------------------------------------===// #include "clang/AST/APValue.h" #include "clang/AST/ASTContext.h" #include "clang/AST/Attr.h" #include "clang/AST/DeclCXX.h" #include "clang/AST/DeclObjC.h" #include "clang/AST/DeclTemplate.h" #include "clang/AST/EvaluatedExprVisitor.h" #include "clang/AST/Expr.h" #include "clang/AST/ExprCXX.h" #include "clang/AST/Mangle.h" #include "clang/AST/RecordLayout.h" #include "clang/AST/StmtVisitor.h" #include "clang/Basic/Builtins.h" #include "clang/Basic/CharInfo.h" #include "clang/Basic/SourceManager.h" #include "clang/Basic/TargetInfo.h" #include "clang/Lex/Lexer.h" #include "clang/Lex/LiteralSupport.h" #include "clang/Sema/SemaDiagnostic.h" #include "llvm/Support/ErrorHandling.h" #include "llvm/Support/raw_ostream.h" #include
#include
using namespace clang; const CXXRecordDecl *Expr::getBestDynamicClassType() const { const Expr *E = ignoreParenBaseCasts(); QualType DerivedType = E->getType(); if (const PointerType *PTy = DerivedType->getAs
()) DerivedType = PTy->getPointeeType(); if (DerivedType->isDependentType()) return nullptr; const RecordType *Ty = DerivedType->castAs
(); Decl *D = Ty->getDecl(); return cast
(D); } const Expr *Expr::skipRValueSubobjectAdjustments( SmallVectorImpl
&CommaLHSs, SmallVectorImpl
&Adjustments) const { const Expr *E = this; while (true) { E = E->IgnoreParens(); if (const CastExpr *CE = dyn_cast
(E)) { if ((CE->getCastKind() == CK_DerivedToBase || CE->getCastKind() == CK_UncheckedDerivedToBase) && E->getType()->isRecordType()) { E = CE->getSubExpr(); CXXRecordDecl *Derived = cast
(E->getType()->getAs
()->getDecl()); Adjustments.push_back(SubobjectAdjustment(CE, Derived)); continue; } if (CE->getCastKind() == CK_NoOp) { E = CE->getSubExpr(); continue; } } else if (const MemberExpr *ME = dyn_cast
(E)) { if (!ME->isArrow()) { assert(ME->getBase()->getType()->isRecordType()); if (FieldDecl *Field = dyn_cast
(ME->getMemberDecl())) { if (!Field->isBitField() && !Field->getType()->isReferenceType()) { E = ME->getBase(); Adjustments.push_back(SubobjectAdjustment(Field)); continue; } } } } else if (const BinaryOperator *BO = dyn_cast
(E)) { if (BO->isPtrMemOp()) { assert(BO->getRHS()->isRValue()); E = BO->getLHS(); const MemberPointerType *MPT = BO->getRHS()->getType()->getAs
(); Adjustments.push_back(SubobjectAdjustment(MPT, BO->getRHS())); continue; } else if (BO->getOpcode() == BO_Comma) { CommaLHSs.push_back(BO->getLHS()); E = BO->getRHS(); continue; } } // Nothing changed. break; } return E; } /// isKnownToHaveBooleanValue - Return true if this is an integer expression /// that is known to return 0 or 1. This happens for _Bool/bool expressions /// but also int expressions which are produced by things like comparisons in /// C. bool Expr::isKnownToHaveBooleanValue() const { const Expr *E = IgnoreParens(); // If this value has _Bool type, it is obvious 0/1. if (E->getType()->isBooleanType()) return true; // If this is a non-scalar-integer type, we don't care enough to try. if (!E->getType()->isIntegralOrEnumerationType()) return false; if (const UnaryOperator *UO = dyn_cast
(E)) { switch (UO->getOpcode()) { case UO_Plus: return UO->getSubExpr()->isKnownToHaveBooleanValue(); case UO_LNot: return true; default: return false; } } // Only look through implicit casts. If the user writes // '(int) (a && b)' treat it as an arbitrary int. if (const ImplicitCastExpr *CE = dyn_cast
(E)) return CE->getSubExpr()->isKnownToHaveBooleanValue(); if (const BinaryOperator *BO = dyn_cast
(E)) { switch (BO->getOpcode()) { default: return false; case BO_LT: // Relational operators. case BO_GT: case BO_LE: case BO_GE: case BO_EQ: // Equality operators. case BO_NE: case BO_LAnd: // AND operator. case BO_LOr: // Logical OR operator. return true; case BO_And: // Bitwise AND operator. case BO_Xor: // Bitwise XOR operator. case BO_Or: // Bitwise OR operator. // Handle things like (x==2)|(y==12). return BO->getLHS()->isKnownToHaveBooleanValue() && BO->getRHS()->isKnownToHaveBooleanValue(); case BO_Comma: case BO_Assign: return BO->getRHS()->isKnownToHaveBooleanValue(); } } if (const ConditionalOperator *CO = dyn_cast
(E)) return CO->getTrueExpr()->isKnownToHaveBooleanValue() && CO->getFalseExpr()->isKnownToHaveBooleanValue(); return false; } // Amusing macro metaprogramming hack: check whether a class provides // a more specific implementation of getExprLoc(). // // See also Stmt.cpp:{getLocStart(),getLocEnd()}. namespace { /// This implementation is used when a class provides a custom /// implementation of getExprLoc. template
SourceLocation getExprLocImpl(const Expr *expr, SourceLocation (T::*v)() const) { return static_cast
(expr)->getExprLoc(); } /// This implementation is used when a class doesn't provide /// a custom implementation of getExprLoc. Overload resolution /// should pick it over the implementation above because it's /// more specialized according to function template partial ordering. template
SourceLocation getExprLocImpl(const Expr *expr, SourceLocation (Expr::*v)() const) { return static_cast
(expr)->getLocStart(); } } SourceLocation Expr::getExprLoc() const { switch (getStmtClass()) { case Stmt::NoStmtClass: llvm_unreachable("statement without class"); #define ABSTRACT_STMT(type) #define STMT(type, base) \ case Stmt::type##Class: break; #define EXPR(type, base) \ case Stmt::type##Class: return getExprLocImpl
(this, &type::getExprLoc); #include "clang/AST/StmtNodes.inc" } llvm_unreachable("unknown expression kind"); } //===----------------------------------------------------------------------===// // Primary Expressions. //===----------------------------------------------------------------------===// /// \brief Compute the type-, value-, and instantiation-dependence of a /// declaration reference /// based on the declaration being referenced. static void computeDeclRefDependence(const ASTContext &Ctx, NamedDecl *D, QualType T, bool &TypeDependent, bool &ValueDependent, bool &InstantiationDependent) { TypeDependent = false; ValueDependent = false; InstantiationDependent = false; // (TD) C++ [temp.dep.expr]p3: // An id-expression is type-dependent if it contains: // // and // // (VD) C++ [temp.dep.constexpr]p2: // An identifier is value-dependent if it is: // (TD) - an identifier that was declared with dependent type // (VD) - a name declared with a dependent type, if (T->isDependentType()) { TypeDependent = true; ValueDependent = true; InstantiationDependent = true; return; } else if (T->isInstantiationDependentType()) { InstantiationDependent = true; } // (TD) - a conversion-function-id that specifies a dependent type if (D->getDeclName().getNameKind() == DeclarationName::CXXConversionFunctionName) { QualType T = D->getDeclName().getCXXNameType(); if (T->isDependentType()) { TypeDependent = true; ValueDependent = true; InstantiationDependent = true; return; } if (T->isInstantiationDependentType()) InstantiationDependent = true; } // (VD) - the name of a non-type template parameter, if (isa
(D)) { ValueDependent = true; InstantiationDependent = true; return; } // (VD) - a constant with integral or enumeration type and is // initialized with an expression that is value-dependent. // (VD) - a constant with literal type and is initialized with an // expression that is value-dependent [C++11]. // (VD) - FIXME: Missing from the standard: // - an entity with reference type and is initialized with an // expression that is value-dependent [C++11] if (VarDecl *Var = dyn_cast
(D)) { if ((Ctx.getLangOpts().CPlusPlus11 ? Var->getType()->isLiteralType(Ctx) : Var->getType()->isIntegralOrEnumerationType()) && (Var->getType().isConstQualified() || Var->getType()->isReferenceType())) { if (const Expr *Init = Var->getAnyInitializer()) if (Init->isValueDependent()) { ValueDependent = true; InstantiationDependent = true; } } // (VD) - FIXME: Missing from the standard: // - a member function or a static data member of the current // instantiation if (Var->isStaticDataMember() && Var->getDeclContext()->isDependentContext()) { ValueDependent = true; InstantiationDependent = true; TypeSourceInfo *TInfo = Var->getFirstDecl()->getTypeSourceInfo(); if (TInfo->getType()->isIncompleteArrayType()) TypeDependent = true; } return; } // (VD) - FIXME: Missing from the standard: // - a member function or a static data member of the current // instantiation if (isa
(D) && D->getDeclContext()->isDependentContext()) { ValueDependent = true; InstantiationDependent = true; } } void DeclRefExpr::computeDependence(const ASTContext &Ctx) { bool TypeDependent = false; bool ValueDependent = false; bool InstantiationDependent = false; computeDeclRefDependence(Ctx, getDecl(), getType(), TypeDependent, ValueDependent, InstantiationDependent); ExprBits.TypeDependent |= TypeDependent; ExprBits.ValueDependent |= ValueDependent; ExprBits.InstantiationDependent |= InstantiationDependent; // Is the declaration a parameter pack? if (getDecl()->isParameterPack()) ExprBits.ContainsUnexpandedParameterPack = true; } DeclRefExpr::DeclRefExpr(const ASTContext &Ctx, NestedNameSpecifierLoc QualifierLoc, SourceLocation TemplateKWLoc, ValueDecl *D, bool RefersToEnclosingVariableOrCapture, const DeclarationNameInfo &NameInfo, NamedDecl *FoundD, const TemplateArgumentListInfo *TemplateArgs, QualType T, ExprValueKind VK) : Expr(DeclRefExprClass, T, VK, OK_Ordinary, false, false, false, false), D(D), Loc(NameInfo.getLoc()), DNLoc(NameInfo.getInfo()) { DeclRefExprBits.HasQualifier = QualifierLoc ? 1 : 0; if (QualifierLoc) { new (getTrailingObjects
()) NestedNameSpecifierLoc(QualifierLoc); auto *NNS = QualifierLoc.getNestedNameSpecifier(); if (NNS->isInstantiationDependent()) ExprBits.InstantiationDependent = true; if (NNS->containsUnexpandedParameterPack()) ExprBits.ContainsUnexpandedParameterPack = true; } DeclRefExprBits.HasFoundDecl = FoundD ? 1 : 0; if (FoundD) *getTrailingObjects
() = FoundD; DeclRefExprBits.HasTemplateKWAndArgsInfo = (TemplateArgs || TemplateKWLoc.isValid()) ? 1 : 0; DeclRefExprBits.RefersToEnclosingVariableOrCapture = RefersToEnclosingVariableOrCapture; if (TemplateArgs) { bool Dependent = false; bool InstantiationDependent = false; bool ContainsUnexpandedParameterPack = false; getTrailingObjects
()->initializeFrom( TemplateKWLoc, *TemplateArgs, getTrailingObjects
(), Dependent, InstantiationDependent, ContainsUnexpandedParameterPack); assert(!Dependent && "built a DeclRefExpr with dependent template args"); ExprBits.InstantiationDependent |= InstantiationDependent; ExprBits.ContainsUnexpandedParameterPack |= ContainsUnexpandedParameterPack; } else if (TemplateKWLoc.isValid()) { getTrailingObjects
()->initializeFrom( TemplateKWLoc); } DeclRefExprBits.HadMultipleCandidates = 0; computeDependence(Ctx); } DeclRefExpr *DeclRefExpr::Create(const ASTContext &Context, NestedNameSpecifierLoc QualifierLoc, SourceLocation TemplateKWLoc, ValueDecl *D, bool RefersToEnclosingVariableOrCapture, SourceLocation NameLoc, QualType T, ExprValueKind VK, NamedDecl *FoundD, const TemplateArgumentListInfo *TemplateArgs) { return Create(Context, QualifierLoc, TemplateKWLoc, D, RefersToEnclosingVariableOrCapture, DeclarationNameInfo(D->getDeclName(), NameLoc), T, VK, FoundD, TemplateArgs); } DeclRefExpr *DeclRefExpr::Create(const ASTContext &Context, NestedNameSpecifierLoc QualifierLoc, SourceLocation TemplateKWLoc, ValueDecl *D, bool RefersToEnclosingVariableOrCapture, const DeclarationNameInfo &NameInfo, QualType T, ExprValueKind VK, NamedDecl *FoundD, const TemplateArgumentListInfo *TemplateArgs) { // Filter out cases where the found Decl is the same as the value refenenced. if (D == FoundD) FoundD = nullptr; bool HasTemplateKWAndArgsInfo = TemplateArgs || TemplateKWLoc.isValid(); std::size_t Size = totalSizeToAlloc
( QualifierLoc ? 1 : 0, FoundD ? 1 : 0, HasTemplateKWAndArgsInfo ? 1 : 0, TemplateArgs ? TemplateArgs->size() : 0); void *Mem = Context.Allocate(Size, llvm::alignOf
()); return new (Mem) DeclRefExpr(Context, QualifierLoc, TemplateKWLoc, D, RefersToEnclosingVariableOrCapture, NameInfo, FoundD, TemplateArgs, T, VK); } DeclRefExpr *DeclRefExpr::CreateEmpty(const ASTContext &Context, bool HasQualifier, bool HasFoundDecl, bool HasTemplateKWAndArgsInfo, unsigned NumTemplateArgs) { assert(NumTemplateArgs == 0 || HasTemplateKWAndArgsInfo); std::size_t Size = totalSizeToAlloc
( HasQualifier ? 1 : 0, HasFoundDecl ? 1 : 0, HasTemplateKWAndArgsInfo, NumTemplateArgs); void *Mem = Context.Allocate(Size, llvm::alignOf
()); return new (Mem) DeclRefExpr(EmptyShell()); } SourceLocation DeclRefExpr::getLocStart() const { if (hasQualifier()) return getQualifierLoc().getBeginLoc(); return getNameInfo().getLocStart(); } SourceLocation DeclRefExpr::getLocEnd() const { if (hasExplicitTemplateArgs()) return getRAngleLoc(); return getNameInfo().getLocEnd(); } PredefinedExpr::PredefinedExpr(SourceLocation L, QualType FNTy, IdentType IT, StringLiteral *SL) : Expr(PredefinedExprClass, FNTy, VK_LValue, OK_Ordinary, FNTy->isDependentType(), FNTy->isDependentType(), FNTy->isInstantiationDependentType(), /*ContainsUnexpandedParameterPack=*/false), Loc(L), Type(IT), FnName(SL) {} StringLiteral *PredefinedExpr::getFunctionName() { return cast_or_null
(FnName); } StringRef PredefinedExpr::getIdentTypeName(PredefinedExpr::IdentType IT) { switch (IT) { case Func: return "__func__"; case Function: return "__FUNCTION__"; case FuncDName: return "__FUNCDNAME__"; case LFunction: return "L__FUNCTION__"; case PrettyFunction: return "__PRETTY_FUNCTION__"; case FuncSig: return "__FUNCSIG__"; case PrettyFunctionNoVirtual: break; } llvm_unreachable("Unknown ident type for PredefinedExpr"); } // FIXME: Maybe this should use DeclPrinter with a special "print predefined // expr" policy instead. std::string PredefinedExpr::ComputeName(IdentType IT, const Decl *CurrentDecl) { ASTContext &Context = CurrentDecl->getASTContext(); if (IT == PredefinedExpr::FuncDName) { if (const NamedDecl *ND = dyn_cast
(CurrentDecl)) { std::unique_ptr
MC; MC.reset(Context.createMangleContext()); if (MC->shouldMangleDeclName(ND)) { SmallString<256> Buffer; llvm::raw_svector_ostream Out(Buffer); if (const CXXConstructorDecl *CD = dyn_cast
(ND)) MC->mangleCXXCtor(CD, Ctor_Base, Out); else if (const CXXDestructorDecl *DD = dyn_cast
(ND)) MC->mangleCXXDtor(DD, Dtor_Base, Out); else MC->mangleName(ND, Out); if (!Buffer.empty() && Buffer.front() == '\01') return Buffer.substr(1); return Buffer.str(); } else return ND->getIdentifier()->getName(); } return ""; } if (auto *BD = dyn_cast
(CurrentDecl)) { std::unique_ptr
MC; MC.reset(Context.createMangleContext()); SmallString<256> Buffer; llvm::raw_svector_ostream Out(Buffer); auto DC = CurrentDecl->getDeclContext(); if (DC->isFileContext()) MC->mangleGlobalBlock(BD, /*ID*/ nullptr, Out); else if (const auto *CD = dyn_cast
(DC)) MC->mangleCtorBlock(CD, /*CT*/ Ctor_Complete, BD, Out); else if (const auto *DD = dyn_cast
(DC)) MC->mangleDtorBlock(DD, /*DT*/ Dtor_Complete, BD, Out); else MC->mangleBlock(DC, BD, Out); return Out.str(); } if (const FunctionDecl *FD = dyn_cast
(CurrentDecl)) { if (IT != PrettyFunction && IT != PrettyFunctionNoVirtual && IT != FuncSig) return FD->getNameAsString(); SmallString<256> Name; llvm::raw_svector_ostream Out(Name); if (const CXXMethodDecl *MD = dyn_cast
(FD)) { if (MD->isVirtual() && IT != PrettyFunctionNoVirtual) Out << "virtual "; if (MD->isStatic()) Out << "static "; } PrintingPolicy Policy(Context.getLangOpts()); std::string Proto; llvm::raw_string_ostream POut(Proto); const FunctionDecl *Decl = FD; if (const FunctionDecl* Pattern = FD->getTemplateInstantiationPattern()) Decl = Pattern; const FunctionType *AFT = Decl->getType()->getAs
(); const FunctionProtoType *FT = nullptr; if (FD->hasWrittenPrototype()) FT = dyn_cast
(AFT); if (IT == FuncSig) { switch (FT->getCallConv()) { case CC_C: POut << "__cdecl "; break; case CC_X86StdCall: POut << "__stdcall "; break; case CC_X86FastCall: POut << "__fastcall "; break; case CC_X86ThisCall: POut << "__thiscall "; break; case CC_X86VectorCall: POut << "__vectorcall "; break; // Only bother printing the conventions that MSVC knows about. default: break; } } FD->printQualifiedName(POut, Policy); POut << "("; if (FT) { for (unsigned i = 0, e = Decl->getNumParams(); i != e; ++i) { if (i) POut << ", "; POut << Decl->getParamDecl(i)->getType().stream(Policy); } if (FT->isVariadic()) { if (FD->getNumParams()) POut << ", "; POut << "..."; } } POut << ")"; if (const CXXMethodDecl *MD = dyn_cast
(FD)) { const FunctionType *FT = MD->getType()->castAs
(); if (FT->isConst()) POut << " const"; if (FT->isVolatile()) POut << " volatile"; RefQualifierKind Ref = MD->getRefQualifier(); if (Ref == RQ_LValue) POut << " &"; else if (Ref == RQ_RValue) POut << " &&"; } typedef SmallVector
SpecsTy; SpecsTy Specs; const DeclContext *Ctx = FD->getDeclContext(); while (Ctx && isa
(Ctx)) { const ClassTemplateSpecializationDecl *Spec = dyn_cast
(Ctx); if (Spec && !Spec->isExplicitSpecialization()) Specs.push_back(Spec); Ctx = Ctx->getParent(); } std::string TemplateParams; llvm::raw_string_ostream TOut(TemplateParams); for (SpecsTy::reverse_iterator I = Specs.rbegin(), E = Specs.rend(); I != E; ++I) { const TemplateParameterList *Params = (*I)->getSpecializedTemplate()->getTemplateParameters(); const TemplateArgumentList &Args = (*I)->getTemplateArgs(); assert(Params->size() == Args.size()); for (unsigned i = 0, numParams = Params->size(); i != numParams; ++i) { StringRef Param = Params->getParam(i)->getName(); if (Param.empty()) continue; TOut << Param << " = "; Args.get(i).print(Policy, TOut); TOut << ", "; } } FunctionTemplateSpecializationInfo *FSI = FD->getTemplateSpecializationInfo(); if (FSI && !FSI->isExplicitSpecialization()) { const TemplateParameterList* Params = FSI->getTemplate()->getTemplateParameters(); const TemplateArgumentList* Args = FSI->TemplateArguments; assert(Params->size() == Args->size()); for (unsigned i = 0, e = Params->size(); i != e; ++i) { StringRef Param = Params->getParam(i)->getName(); if (Param.empty()) continue; TOut << Param << " = "; Args->get(i).print(Policy, TOut); TOut << ", "; } } TOut.flush(); if (!TemplateParams.empty()) { // remove the trailing comma and space TemplateParams.resize(TemplateParams.size() - 2); POut << " [" << TemplateParams << "]"; } POut.flush(); // Print "auto" for all deduced return types. This includes C++1y return // type deduction and lambdas. For trailing return types resolve the // decltype expression. Otherwise print the real type when this is // not a constructor or destructor. if (isa
(FD) && cast
(FD)->getParent()->isLambda()) Proto = "auto " + Proto; else if (FT && FT->getReturnType()->getAs
()) FT->getReturnType() ->getAs
() ->getUnderlyingType() .getAsStringInternal(Proto, Policy); else if (!isa
(FD) && !isa
(FD)) AFT->getReturnType().getAsStringInternal(Proto, Policy); Out << Proto; return Name.str().str(); } if (const CapturedDecl *CD = dyn_cast
(CurrentDecl)) { for (const DeclContext *DC = CD->getParent(); DC; DC = DC->getParent()) // Skip to its enclosing function or method, but not its enclosing // CapturedDecl. if (DC->isFunctionOrMethod() && (DC->getDeclKind() != Decl::Captured)) { const Decl *D = Decl::castFromDeclContext(DC); return ComputeName(IT, D); } llvm_unreachable("CapturedDecl not inside a function or method"); } if (const ObjCMethodDecl *MD = dyn_cast
(CurrentDecl)) { SmallString<256> Name; llvm::raw_svector_ostream Out(Name); Out << (MD->isInstanceMethod() ? '-' : '+'); Out << '['; // For incorrect code, there might not be an ObjCInterfaceDecl. Do // a null check to avoid a crash. if (const ObjCInterfaceDecl *ID = MD->getClassInterface()) Out << *ID; if (const ObjCCategoryImplDecl *CID = dyn_cast
(MD->getDeclContext())) Out << '(' << *CID << ')'; Out << ' '; MD->getSelector().print(Out); Out << ']'; return Name.str().str(); } if (isa
(CurrentDecl) && IT == PrettyFunction) { // __PRETTY_FUNCTION__ -> "top level", the others produce an empty string. return "top level"; } return ""; } void APNumericStorage::setIntValue(const ASTContext &C, const llvm::APInt &Val) { if (hasAllocation()) C.Deallocate(pVal); BitWidth = Val.getBitWidth(); unsigned NumWords = Val.getNumWords(); const uint64_t* Words = Val.getRawData(); if (NumWords > 1) { pVal = new (C) uint64_t[NumWords]; std::copy(Words, Words + NumWords, pVal); } else if (NumWords == 1) VAL = Words[0]; else VAL = 0; } IntegerLiteral::IntegerLiteral(const ASTContext &C, const llvm::APInt &V, QualType type, SourceLocation l) : Expr(IntegerLiteralClass, type, VK_RValue, OK_Ordinary, false, false, false, false), Loc(l) { assert(type->isIntegerType() && "Illegal type in IntegerLiteral"); assert(V.getBitWidth() == C.getIntWidth(type) && "Integer type is not the correct size for constant."); setValue(C, V); } IntegerLiteral * IntegerLiteral::Create(const ASTContext &C, const llvm::APInt &V, QualType type, SourceLocation l) { return new (C) IntegerLiteral(C, V, type, l); } IntegerLiteral * IntegerLiteral::Create(const ASTContext &C, EmptyShell Empty) { return new (C) IntegerLiteral(Empty); } FloatingLiteral::FloatingLiteral(const ASTContext &C, const llvm::APFloat &V, bool isexact, QualType Type, SourceLocation L) : Expr(FloatingLiteralClass, Type, VK_RValue, OK_Ordinary, false, false, false, false), Loc(L) { setSemantics(V.getSemantics()); FloatingLiteralBits.IsExact = isexact; setValue(C, V); } FloatingLiteral::FloatingLiteral(const ASTContext &C, EmptyShell Empty) : Expr(FloatingLiteralClass, Empty) { setRawSemantics(IEEEhalf); FloatingLiteralBits.IsExact = false; } FloatingLiteral * FloatingLiteral::Create(const ASTContext &C, const llvm::APFloat &V, bool isexact, QualType Type, SourceLocation L) { return new (C) FloatingLiteral(C, V, isexact, Type, L); } FloatingLiteral * FloatingLiteral::Create(const ASTContext &C, EmptyShell Empty) { return new (C) FloatingLiteral(C, Empty); } const llvm::fltSemantics &FloatingLiteral::getSemantics() const { switch(FloatingLiteralBits.Semantics) { case IEEEhalf: return llvm::APFloat::IEEEhalf; case IEEEsingle: return llvm::APFloat::IEEEsingle; case IEEEdouble: return llvm::APFloat::IEEEdouble; case x87DoubleExtended: return llvm::APFloat::x87DoubleExtended; case IEEEquad: return llvm::APFloat::IEEEquad; case PPCDoubleDouble: return llvm::APFloat::PPCDoubleDouble; } llvm_unreachable("Unrecognised floating semantics"); } void FloatingLiteral::setSemantics(const llvm::fltSemantics &Sem) { if (&Sem == &llvm::APFloat::IEEEhalf) FloatingLiteralBits.Semantics = IEEEhalf; else if (&Sem == &llvm::APFloat::IEEEsingle) FloatingLiteralBits.Semantics = IEEEsingle; else if (&Sem == &llvm::APFloat::IEEEdouble) FloatingLiteralBits.Semantics = IEEEdouble; else if (&Sem == &llvm::APFloat::x87DoubleExtended) FloatingLiteralBits.Semantics = x87DoubleExtended; else if (&Sem == &llvm::APFloat::IEEEquad) FloatingLiteralBits.Semantics = IEEEquad; else if (&Sem == &llvm::APFloat::PPCDoubleDouble) FloatingLiteralBits.Semantics = PPCDoubleDouble; else llvm_unreachable("Unknown floating semantics"); } /// getValueAsApproximateDouble - This returns the value as an inaccurate /// double. Note that this may cause loss of precision, but is useful for /// debugging dumps, etc. double FloatingLiteral::getValueAsApproximateDouble() const { llvm::APFloat V = getValue(); bool ignored; V.convert(llvm::APFloat::IEEEdouble, llvm::APFloat::rmNearestTiesToEven, &ignored); return V.convertToDouble(); } int StringLiteral::mapCharByteWidth(TargetInfo const &target,StringKind k) { int CharByteWidth = 0; switch(k) { case Ascii: case UTF8: CharByteWidth = target.getCharWidth(); break; case Wide: CharByteWidth = target.getWCharWidth(); break; case UTF16: CharByteWidth = target.getChar16Width(); break; case UTF32: CharByteWidth = target.getChar32Width(); break; } assert((CharByteWidth & 7) == 0 && "Assumes character size is byte multiple"); CharByteWidth /= 8; assert((CharByteWidth==1 || CharByteWidth==2 || CharByteWidth==4) && "character byte widths supported are 1, 2, and 4 only"); return CharByteWidth; } StringLiteral *StringLiteral::Create(const ASTContext &C, StringRef Str, StringKind Kind, bool Pascal, QualType Ty, const SourceLocation *Loc, unsigned NumStrs) { assert(C.getAsConstantArrayType(Ty) && "StringLiteral must be of constant array type!"); // Allocate enough space for the StringLiteral plus an array of locations for // any concatenated string tokens. void *Mem = C.Allocate(sizeof(StringLiteral)+ sizeof(SourceLocation)*(NumStrs-1), llvm::alignOf
()); StringLiteral *SL = new (Mem) StringLiteral(Ty); // OPTIMIZE: could allocate this appended to the StringLiteral. SL->setString(C,Str,Kind,Pascal); SL->TokLocs[0] = Loc[0]; SL->NumConcatenated = NumStrs; if (NumStrs != 1) memcpy(&SL->TokLocs[1], Loc+1, sizeof(SourceLocation)*(NumStrs-1)); return SL; } StringLiteral *StringLiteral::CreateEmpty(const ASTContext &C, unsigned NumStrs) { void *Mem = C.Allocate(sizeof(StringLiteral)+ sizeof(SourceLocation)*(NumStrs-1), llvm::alignOf
()); StringLiteral *SL = new (Mem) StringLiteral(QualType()); SL->CharByteWidth = 0; SL->Length = 0; SL->NumConcatenated = NumStrs; return SL; } void StringLiteral::outputString(raw_ostream &OS) const { switch (getKind()) { case Ascii: break; // no prefix. case Wide: OS << 'L'; break; case UTF8: OS << "u8"; break; case UTF16: OS << 'u'; break; case UTF32: OS << 'U'; break; } OS << '"'; static const char Hex[] = "0123456789ABCDEF"; unsigned LastSlashX = getLength(); for (unsigned I = 0, N = getLength(); I != N; ++I) { switch (uint32_t Char = getCodeUnit(I)) { default: // FIXME: Convert UTF-8 back to codepoints before rendering. // Convert UTF-16 surrogate pairs back to codepoints before rendering. // Leave invalid surrogates alone; we'll use \x for those. if (getKind() == UTF16 && I != N - 1 && Char >= 0xd800 && Char <= 0xdbff) { uint32_t Trail = getCodeUnit(I + 1); if (Trail >= 0xdc00 && Trail <= 0xdfff) { Char = 0x10000 + ((Char - 0xd800) << 10) + (Trail - 0xdc00); ++I; } } if (Char > 0xff) { // If this is a wide string, output characters over 0xff using \x // escapes. Otherwise, this is a UTF-16 or UTF-32 string, and Char is a // codepoint: use \x escapes for invalid codepoints. if (getKind() == Wide || (Char >= 0xd800 && Char <= 0xdfff) || Char >= 0x110000) { // FIXME: Is this the best way to print wchar_t? OS << "\\x"; int Shift = 28; while ((Char >> Shift) == 0) Shift -= 4; for (/**/; Shift >= 0; Shift -= 4) OS << Hex[(Char >> Shift) & 15]; LastSlashX = I; break; } if (Char > 0xffff) OS << "\\U00" << Hex[(Char >> 20) & 15] << Hex[(Char >> 16) & 15]; else OS << "\\u"; OS << Hex[(Char >> 12) & 15] << Hex[(Char >> 8) & 15] << Hex[(Char >> 4) & 15] << Hex[(Char >> 0) & 15]; break; } // If we used \x... for the previous character, and this character is a // hexadecimal digit, prevent it being slurped as part of the \x. if (LastSlashX + 1 == I) { switch (Char) { case '0': case '1': case '2': case '3': case '4': case '5': case '6': case '7': case '8': case '9': case 'a': case 'b': case 'c': case 'd': case 'e': case 'f': case 'A': case 'B': case 'C': case 'D': case 'E': case 'F': OS << "\"\""; } } assert(Char <= 0xff && "Characters above 0xff should already have been handled."); if (isPrintable(Char)) OS << (char)Char; else // Output anything hard as an octal escape. OS << '\\' << (char)('0' + ((Char >> 6) & 7)) << (char)('0' + ((Char >> 3) & 7)) << (char)('0' + ((Char >> 0) & 7)); break; // Handle some common non-printable cases to make dumps prettier. case '\\': OS << "\\\\"; break; case '"': OS << "\\\""; break; case '\n': OS << "\\n"; break; case '\t': OS << "\\t"; break; case '\a': OS << "\\a"; break; case '\b': OS << "\\b"; break; } } OS << '"'; } void StringLiteral::setString(const ASTContext &C, StringRef Str, StringKind Kind, bool IsPascal) { //FIXME: we assume that the string data comes from a target that uses the same // code unit size and endianess for the type of string. this->Kind = Kind; this->IsPascal = IsPascal; CharByteWidth = mapCharByteWidth(C.getTargetInfo(),Kind); assert((Str.size()%CharByteWidth == 0) && "size of data must be multiple of CharByteWidth"); Length = Str.size()/CharByteWidth; switch(CharByteWidth) { case 1: { char *AStrData = new (C) char[Length]; std::memcpy(AStrData,Str.data(),Length*sizeof(*AStrData)); StrData.asChar = AStrData; break; } case 2: { uint16_t *AStrData = new (C) uint16_t[Length]; std::memcpy(AStrData,Str.data(),Length*sizeof(*AStrData)); StrData.asUInt16 = AStrData; break; } case 4: { uint32_t *AStrData = new (C) uint32_t[Length]; std::memcpy(AStrData,Str.data(),Length*sizeof(*AStrData)); StrData.asUInt32 = AStrData; break; } default: llvm_unreachable("unsupported CharByteWidth"); } } /// getLocationOfByte - Return a source location that points to the specified /// byte of this string literal. /// /// Strings are amazingly complex. They can be formed from multiple tokens and /// can have escape sequences in them in addition to the usual trigraph and /// escaped newline business. This routine handles this complexity. /// /// The *StartToken sets the first token to be searched in this function and /// the *StartTokenByteOffset is the byte offset of the first token. Before /// returning, it updates the *StartToken to the TokNo of the token being found /// and sets *StartTokenByteOffset to the byte offset of the token in the /// string. /// Using these two parameters can reduce the time complexity from O(n^2) to /// O(n) if one wants to get the location of byte for all the tokens in a /// string. /// SourceLocation StringLiteral::getLocationOfByte(unsigned ByteNo, const SourceManager &SM, const LangOptions &Features, const TargetInfo &Target, unsigned *StartToken, unsigned *StartTokenByteOffset) const { assert((Kind == StringLiteral::Ascii || Kind == StringLiteral::UTF8) && "Only narrow string literals are currently supported"); // Loop over all of the tokens in this string until we find the one that // contains the byte we're looking for. unsigned TokNo = 0; unsigned StringOffset = 0; if (StartToken) TokNo = *StartToken; if (StartTokenByteOffset) { StringOffset = *StartTokenByteOffset; ByteNo -= StringOffset; } while (1) { assert(TokNo < getNumConcatenated() && "Invalid byte number!"); SourceLocation StrTokLoc = getStrTokenLoc(TokNo); // Get the spelling of the string so that we can get the data that makes up // the string literal, not the identifier for the macro it is potentially // expanded through. SourceLocation StrTokSpellingLoc = SM.getSpellingLoc(StrTokLoc); // Re-lex the token to get its length and original spelling. std::pair
LocInfo = SM.getDecomposedLoc(StrTokSpellingLoc); bool Invalid = false; StringRef Buffer = SM.getBufferData(LocInfo.first, &Invalid); if (Invalid) { if (StartTokenByteOffset != nullptr) *StartTokenByteOffset = StringOffset; if (StartToken != nullptr) *StartToken = TokNo; return StrTokSpellingLoc; } const char *StrData = Buffer.data()+LocInfo.second; // Create a lexer starting at the beginning of this token. Lexer TheLexer(SM.getLocForStartOfFile(LocInfo.first), Features, Buffer.begin(), StrData, Buffer.end()); Token TheTok; TheLexer.LexFromRawLexer(TheTok); // Use the StringLiteralParser to compute the length of the string in bytes. StringLiteralParser SLP(TheTok, SM, Features, Target); unsigned TokNumBytes = SLP.GetStringLength(); // If the byte is in this token, return the location of the byte. if (ByteNo < TokNumBytes || (ByteNo == TokNumBytes && TokNo == getNumConcatenated() - 1)) { unsigned Offset = SLP.getOffsetOfStringByte(TheTok, ByteNo); // Now that we know the offset of the token in the spelling, use the // preprocessor to get the offset in the original source. if (StartTokenByteOffset != nullptr) *StartTokenByteOffset = StringOffset; if (StartToken != nullptr) *StartToken = TokNo; return Lexer::AdvanceToTokenCharacter(StrTokLoc, Offset, SM, Features); } // Move to the next string token. StringOffset += TokNumBytes; ++TokNo; ByteNo -= TokNumBytes; } } /// getOpcodeStr - Turn an Opcode enum value into the punctuation char it /// corresponds to, e.g. "sizeof" or "[pre]++". StringRef UnaryOperator::getOpcodeStr(Opcode Op) { switch (Op) { #define UNARY_OPERATION(Name, Spelling) case UO_##Name: return Spelling; #include "clang/AST/OperationKinds.def" } llvm_unreachable("Unknown unary operator"); } UnaryOperatorKind UnaryOperator::getOverloadedOpcode(OverloadedOperatorKind OO, bool Postfix) { switch (OO) { default: llvm_unreachable("No unary operator for overloaded function"); case OO_PlusPlus: return Postfix ? UO_PostInc : UO_PreInc; case OO_MinusMinus: return Postfix ? UO_PostDec : UO_PreDec; case OO_Amp: return UO_AddrOf; case OO_Star: return UO_Deref; case OO_Plus: return UO_Plus; case OO_Minus: return UO_Minus; case OO_Tilde: return UO_Not; case OO_Exclaim: return UO_LNot; case OO_Coawait: return UO_Coawait; } } OverloadedOperatorKind UnaryOperator::getOverloadedOperator(Opcode Opc) { switch (Opc) { case UO_PostInc: case UO_PreInc: return OO_PlusPlus; case UO_PostDec: case UO_PreDec: return OO_MinusMinus; case UO_AddrOf: return OO_Amp; case UO_Deref: return OO_Star; case UO_Plus: return OO_Plus; case UO_Minus: return OO_Minus; case UO_Not: return OO_Tilde; case UO_LNot: return OO_Exclaim; case UO_Coawait: return OO_Coawait; default: return OO_None; } } //===----------------------------------------------------------------------===// // Postfix Operators. //===----------------------------------------------------------------------===// CallExpr::CallExpr(const ASTContext &C, StmtClass SC, Expr *fn, ArrayRef
preargs, ArrayRef
args, QualType t, ExprValueKind VK, SourceLocation rparenloc) : Expr(SC, t, VK, OK_Ordinary, fn->isTypeDependent(), fn->isValueDependent(), fn->isInstantiationDependent(), fn->containsUnexpandedParameterPack()), NumArgs(args.size()) { unsigned NumPreArgs = preargs.size(); SubExprs = new (C) Stmt *[args.size()+PREARGS_START+NumPreArgs]; SubExprs[FN] = fn; for (unsigned i = 0; i != NumPreArgs; ++i) { updateDependenciesFromArg(preargs[i]); SubExprs[i+PREARGS_START] = preargs[i]; } for (unsigned i = 0; i != args.size(); ++i) { updateDependenciesFromArg(args[i]); SubExprs[i+PREARGS_START+NumPreArgs] = args[i]; } CallExprBits.NumPreArgs = NumPreArgs; RParenLoc = rparenloc; } CallExpr::CallExpr(const ASTContext &C, StmtClass SC, Expr *fn, ArrayRef
args, QualType t, ExprValueKind VK, SourceLocation rparenloc) : CallExpr(C, SC, fn, ArrayRef
(), args, t, VK, rparenloc) {} CallExpr::CallExpr(const ASTContext &C, Expr *fn, ArrayRef
args, QualType t, ExprValueKind VK, SourceLocation rparenloc) : CallExpr(C, CallExprClass, fn, ArrayRef
(), args, t, VK, rparenloc) { } CallExpr::CallExpr(const ASTContext &C, StmtClass SC, EmptyShell Empty) : CallExpr(C, SC, /*NumPreArgs=*/0, Empty) {} CallExpr::CallExpr(const ASTContext &C, StmtClass SC, unsigned NumPreArgs, EmptyShell Empty) : Expr(SC, Empty), SubExprs(nullptr), NumArgs(0) { // FIXME: Why do we allocate this? SubExprs = new (C) Stmt*[PREARGS_START+NumPreArgs](); CallExprBits.NumPreArgs = NumPreArgs; } void CallExpr::updateDependenciesFromArg(Expr *Arg) { if (Arg->isTypeDependent()) ExprBits.TypeDependent = true; if (Arg->isValueDependent()) ExprBits.ValueDependent = true; if (Arg->isInstantiationDependent()) ExprBits.InstantiationDependent = true; if (Arg->containsUnexpandedParameterPack()) ExprBits.ContainsUnexpandedParameterPack = true; } Decl *CallExpr::getCalleeDecl() { Expr *CEE = getCallee()->IgnoreParenImpCasts(); while (SubstNonTypeTemplateParmExpr *NTTP = dyn_cast
(CEE)) { CEE = NTTP->getReplacement()->IgnoreParenCasts(); } // If we're calling a dereference, look at the pointer instead. if (BinaryOperator *BO = dyn_cast
(CEE)) { if (BO->isPtrMemOp()) CEE = BO->getRHS()->IgnoreParenCasts(); } else if (UnaryOperator *UO = dyn_cast
(CEE)) { if (UO->getOpcode() == UO_Deref) CEE = UO->getSubExpr()->IgnoreParenCasts(); } if (DeclRefExpr *DRE = dyn_cast
(CEE)) return DRE->getDecl(); if (MemberExpr *ME = dyn_cast
(CEE)) return ME->getMemberDecl(); return nullptr; } FunctionDecl *CallExpr::getDirectCallee() { return dyn_cast_or_null
(getCalleeDecl()); } /// setNumArgs - This changes the number of arguments present in this call. /// Any orphaned expressions are deleted by this, and any new operands are set /// to null. void CallExpr::setNumArgs(const ASTContext& C, unsigned NumArgs) { // No change, just return. if (NumArgs == getNumArgs()) return; // If shrinking # arguments, just delete the extras and forgot them. if (NumArgs < getNumArgs()) { this->NumArgs = NumArgs; return; } // Otherwise, we are growing the # arguments. New an bigger argument array. unsigned NumPreArgs = getNumPreArgs(); Stmt **NewSubExprs = new (C) Stmt*[NumArgs+PREARGS_START+NumPreArgs]; // Copy over args. for (unsigned i = 0; i != getNumArgs()+PREARGS_START+NumPreArgs; ++i) NewSubExprs[i] = SubExprs[i]; // Null out new args. for (unsigned i = getNumArgs()+PREARGS_START+NumPreArgs; i != NumArgs+PREARGS_START+NumPreArgs; ++i) NewSubExprs[i] = nullptr; if (SubExprs) C.Deallocate(SubExprs); SubExprs = NewSubExprs; this->NumArgs = NumArgs; } /// getBuiltinCallee - If this is a call to a builtin, return the builtin ID. If /// not, return 0. unsigned CallExpr::getBuiltinCallee() const { // All simple function calls (e.g. func()) are implicitly cast to pointer to // function. As a result, we try and obtain the DeclRefExpr from the // ImplicitCastExpr. const ImplicitCastExpr *ICE = dyn_cast
(getCallee()); if (!ICE) // FIXME: deal with more complex calls (e.g. (func)(), (*func)()). return 0; const DeclRefExpr *DRE = dyn_cast
(ICE->getSubExpr()); if (!DRE) return 0; const FunctionDecl *FDecl = dyn_cast
(DRE->getDecl()); if (!FDecl) return 0; if (!FDecl->getIdentifier()) return 0; return FDecl->getBuiltinID(); } bool CallExpr::isUnevaluatedBuiltinCall(const ASTContext &Ctx) const { if (unsigned BI = getBuiltinCallee()) return Ctx.BuiltinInfo.isUnevaluated(BI); return false; } QualType CallExpr::getCallReturnType(const ASTContext &Ctx) const { const Expr *Callee = getCallee(); QualType CalleeType = Callee->getType(); if (const auto *FnTypePtr = CalleeType->getAs
()) { CalleeType = FnTypePtr->getPointeeType(); } else if (const auto *BPT = CalleeType->getAs
()) { CalleeType = BPT->getPointeeType(); } else if (CalleeType->isSpecificPlaceholderType(BuiltinType::BoundMember)) { if (isa
(Callee->IgnoreParens())) return Ctx.VoidTy; // This should never be overloaded and so should never return null. CalleeType = Expr::findBoundMemberType(Callee); } const FunctionType *FnType = CalleeType->castAs
(); return FnType->getReturnType(); } SourceLocation CallExpr::getLocStart() const { if (isa
(this)) return cast
(this)->getLocStart(); SourceLocation begin = getCallee()->getLocStart(); if (begin.isInvalid() && getNumArgs() > 0 && getArg(0)) begin = getArg(0)->getLocStart(); return begin; } SourceLocation CallExpr::getLocEnd() const { if (isa
(this)) return cast
(this)->getLocEnd(); SourceLocation end = getRParenLoc(); if (end.isInvalid() && getNumArgs() > 0 && getArg(getNumArgs() - 1)) end = getArg(getNumArgs() - 1)->getLocEnd(); return end; } OffsetOfExpr *OffsetOfExpr::Create(const ASTContext &C, QualType type, SourceLocation OperatorLoc, TypeSourceInfo *tsi, ArrayRef
comps, ArrayRef
exprs, SourceLocation RParenLoc) { void *Mem = C.Allocate( totalSizeToAlloc
(comps.size(), exprs.size())); return new (Mem) OffsetOfExpr(C, type, OperatorLoc, tsi, comps, exprs, RParenLoc); } OffsetOfExpr *OffsetOfExpr::CreateEmpty(const ASTContext &C, unsigned numComps, unsigned numExprs) { void *Mem = C.Allocate(totalSizeToAlloc
(numComps, numExprs)); return new (Mem) OffsetOfExpr(numComps, numExprs); } OffsetOfExpr::OffsetOfExpr(const ASTContext &C, QualType type, SourceLocation OperatorLoc, TypeSourceInfo *tsi, ArrayRef
comps, ArrayRef
exprs, SourceLocation RParenLoc) : Expr(OffsetOfExprClass, type, VK_RValue, OK_Ordinary, /*TypeDependent=*/false, /*ValueDependent=*/tsi->getType()->isDependentType(), tsi->getType()->isInstantiationDependentType(), tsi->getType()->containsUnexpandedParameterPack()), OperatorLoc(OperatorLoc), RParenLoc(RParenLoc), TSInfo(tsi), NumComps(comps.size()), NumExprs(exprs.size()) { for (unsigned i = 0; i != comps.size(); ++i) { setComponent(i, comps[i]); } for (unsigned i = 0; i != exprs.size(); ++i) { if (exprs[i]->isTypeDependent() || exprs[i]->isValueDependent()) ExprBits.ValueDependent = true; if (exprs[i]->containsUnexpandedParameterPack()) ExprBits.ContainsUnexpandedParameterPack = true; setIndexExpr(i, exprs[i]); } } IdentifierInfo *OffsetOfNode::getFieldName() const { assert(getKind() == Field || getKind() == Identifier); if (getKind() == Field) return getField()->getIdentifier(); return reinterpret_cast
(Data & ~(uintptr_t)Mask); } UnaryExprOrTypeTraitExpr::UnaryExprOrTypeTraitExpr( UnaryExprOrTypeTrait ExprKind, Expr *E, QualType resultType, SourceLocation op, SourceLocation rp) : Expr(UnaryExprOrTypeTraitExprClass, resultType, VK_RValue, OK_Ordinary, false, // Never type-dependent (C++ [temp.dep.expr]p3). // Value-dependent if the argument is type-dependent. E->isTypeDependent(), E->isInstantiationDependent(), E->containsUnexpandedParameterPack()), OpLoc(op), RParenLoc(rp) { UnaryExprOrTypeTraitExprBits.Kind = ExprKind; UnaryExprOrTypeTraitExprBits.IsType = false; Argument.Ex = E; // Check to see if we are in the situation where alignof(decl) should be // dependent because decl's alignment is dependent. if (ExprKind == UETT_AlignOf) { if (!isValueDependent() || !isInstantiationDependent()) { E = E->IgnoreParens(); const ValueDecl *D = nullptr; if (const auto *DRE = dyn_cast
(E)) D = DRE->getDecl(); else if (const auto *ME = dyn_cast
(E)) D = ME->getMemberDecl(); if (D) { for (const auto *I : D->specific_attrs
()) { if (I->isAlignmentDependent()) { setValueDependent(true); setInstantiationDependent(true); break; } } } } } } MemberExpr *MemberExpr::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) { bool hasQualOrFound = (QualifierLoc || founddecl.getDecl() != memberdecl || founddecl.getAccess() != memberdecl->getAccess()); bool HasTemplateKWAndArgsInfo = targs || TemplateKWLoc.isValid(); std::size_t Size = totalSizeToAlloc
(hasQualOrFound ? 1 : 0, HasTemplateKWAndArgsInfo ? 1 : 0, targs ? targs->size() : 0); void *Mem = C.Allocate(Size, llvm::alignOf
()); MemberExpr *E = new (Mem) MemberExpr(base, isarrow, OperatorLoc, memberdecl, nameinfo, ty, vk, ok); if (hasQualOrFound) { // FIXME: Wrong. We should be looking at the member declaration we found. if (QualifierLoc && QualifierLoc.getNestedNameSpecifier()->isDependent()) { E->setValueDependent(true); E->setTypeDependent(true); E->setInstantiationDependent(true); } else if (QualifierLoc && QualifierLoc.getNestedNameSpecifier()->isInstantiationDependent()) E->setInstantiationDependent(true); E->HasQualifierOrFoundDecl = true; MemberExprNameQualifier *NQ = E->getTrailingObjects
(); NQ->QualifierLoc = QualifierLoc; NQ->FoundDecl = founddecl; } E->HasTemplateKWAndArgsInfo = (targs || TemplateKWLoc.isValid()); if (targs) { bool Dependent = false; bool InstantiationDependent = false; bool ContainsUnexpandedParameterPack = false; E->getTrailingObjects
()->initializeFrom( TemplateKWLoc, *targs, E->getTrailingObjects
(), Dependent, InstantiationDependent, ContainsUnexpandedParameterPack); if (InstantiationDependent) E->setInstantiationDependent(true); } else if (TemplateKWLoc.isValid()) { E->getTrailingObjects
()->initializeFrom( TemplateKWLoc); } return E; } SourceLocation MemberExpr::getLocStart() const { if (isImplicitAccess()) { if (hasQualifier()) return getQualifierLoc().getBeginLoc(); return MemberLoc; } // FIXME: We don't want this to happen. Rather, we should be able to // detect all kinds of implicit accesses more cleanly. SourceLocation BaseStartLoc = getBase()->getLocStart(); if (BaseStartLoc.isValid()) return BaseStartLoc; return MemberLoc; } SourceLocation MemberExpr::getLocEnd() const { SourceLocation EndLoc = getMemberNameInfo().getEndLoc(); if (hasExplicitTemplateArgs()) EndLoc = getRAngleLoc(); else if (EndLoc.isInvalid()) EndLoc = getBase()->getLocEnd(); return EndLoc; } bool CastExpr::CastConsistency() const { switch (getCastKind()) { case CK_DerivedToBase: case CK_UncheckedDerivedToBase: case CK_DerivedToBaseMemberPointer: case CK_BaseToDerived: case CK_BaseToDerivedMemberPointer: assert(!path_empty() && "Cast kind should have a base path!"); break; case CK_CPointerToObjCPointerCast: assert(getType()->isObjCObjectPointerType()); assert(getSubExpr()->getType()->isPointerType()); goto CheckNoBasePath; case CK_BlockPointerToObjCPointerCast: assert(getType()->isObjCObjectPointerType()); assert(getSubExpr()->getType()->isBlockPointerType()); goto CheckNoBasePath; case CK_ReinterpretMemberPointer: assert(getType()->isMemberPointerType()); assert(getSubExpr()->getType()->isMemberPointerType()); goto CheckNoBasePath; case CK_BitCast: // Arbitrary casts to C pointer types count as bitcasts. // Otherwise, we should only have block and ObjC pointer casts // here if they stay within the type kind. if (!getType()->isPointerType()) { assert(getType()->isObjCObjectPointerType() == getSubExpr()->getType()->isObjCObjectPointerType()); assert(getType()->isBlockPointerType() == getSubExpr()->getType()->isBlockPointerType()); } goto CheckNoBasePath; case CK_AnyPointerToBlockPointerCast: assert(getType()->isBlockPointerType()); assert(getSubExpr()->getType()->isAnyPointerType() && !getSubExpr()->getType()->isBlockPointerType()); goto CheckNoBasePath; case CK_CopyAndAutoreleaseBlockObject: assert(getType()->isBlockPointerType()); assert(getSubExpr()->getType()->isBlockPointerType()); goto CheckNoBasePath; case CK_FunctionToPointerDecay: assert(getType()->isPointerType()); assert(getSubExpr()->getType()->isFunctionType()); goto CheckNoBasePath; case CK_AddressSpaceConversion: assert(getType()->isPointerType()); assert(getSubExpr()->getType()->isPointerType()); assert(getType()->getPointeeType().getAddressSpace() != getSubExpr()->getType()->getPointeeType().getAddressSpace()); // These should not have an inheritance path. case CK_Dynamic: case CK_ToUnion: case CK_ArrayToPointerDecay: case CK_NullToMemberPointer: case CK_NullToPointer: case CK_ConstructorConversion: case CK_IntegralToPointer: case CK_PointerToIntegral: case CK_ToVoid: case CK_VectorSplat: case CK_IntegralCast: case CK_BooleanToSignedIntegral: case CK_IntegralToFloating: case CK_FloatingToIntegral: case CK_FloatingCast: case CK_ObjCObjectLValueCast: case CK_FloatingRealToComplex: case CK_FloatingComplexToReal: case CK_FloatingComplexCast: case CK_FloatingComplexToIntegralComplex: case CK_IntegralRealToComplex: case CK_IntegralComplexToReal: case CK_IntegralComplexCast: case CK_IntegralComplexToFloatingComplex: case CK_ARCProduceObject: case CK_ARCConsumeObject: case CK_ARCReclaimReturnedObject: case CK_ARCExtendBlockObject: case CK_ZeroToOCLEvent: assert(!getType()->isBooleanType() && "unheralded conversion to bool"); goto CheckNoBasePath; case CK_Dependent: case CK_LValueToRValue: case CK_NoOp: case CK_AtomicToNonAtomic: case CK_NonAtomicToAtomic: case CK_PointerToBoolean: case CK_IntegralToBoolean: case CK_FloatingToBoolean: case CK_MemberPointerToBoolean: case CK_FloatingComplexToBoolean: case CK_IntegralComplexToBoolean: case CK_LValueBitCast: // -> bool& case CK_UserDefinedConversion: // operator bool() case CK_BuiltinFnToFnPtr: CheckNoBasePath: assert(path_empty() && "Cast kind should not have a base path!"); break; } return true; } const char *CastExpr::getCastKindName() const { switch (getCastKind()) { #define CAST_OPERATION(Name) case CK_##Name: return #Name; #include "clang/AST/OperationKinds.def" } llvm_unreachable("Unhandled cast kind!"); } Expr *CastExpr::getSubExprAsWritten() { Expr *SubExpr = nullptr; CastExpr *E = this; do { SubExpr = E->getSubExpr(); // Skip through reference binding to temporary. if (MaterializeTemporaryExpr *Materialize = dyn_cast
(SubExpr)) SubExpr = Materialize->GetTemporaryExpr(); // Skip any temporary bindings; they're implicit. if (CXXBindTemporaryExpr *Binder = dyn_cast
(SubExpr)) SubExpr = Binder->getSubExpr(); // Conversions by constructor and conversion functions have a // subexpression describing the call; strip it off. if (E->getCastKind() == CK_ConstructorConversion) SubExpr = cast
(SubExpr)->getArg(0); else if (E->getCastKind() == CK_UserDefinedConversion) { assert((isa
(SubExpr) || isa
(SubExpr)) && "Unexpected SubExpr for CK_UserDefinedConversion."); if (isa
(SubExpr)) SubExpr = cast
(SubExpr)->getImplicitObjectArgument(); } // If the subexpression we're left with is an implicit cast, look // through that, too. } while ((E = dyn_cast
(SubExpr))); return SubExpr; } CXXBaseSpecifier **CastExpr::path_buffer() { switch (getStmtClass()) { #define ABSTRACT_STMT(x) #define CASTEXPR(Type, Base) \ case Stmt::Type##Class: \ return static_cast
(this)->getTrailingObjects
(); #define STMT(Type, Base) #include "clang/AST/StmtNodes.inc" default: llvm_unreachable("non-cast expressions not possible here"); } } ImplicitCastExpr *ImplicitCastExpr::Create(const ASTContext &C, QualType T, CastKind Kind, Expr *Operand, const CXXCastPath *BasePath, ExprValueKind VK) { unsigned PathSize = (BasePath ? BasePath->size() : 0); void *Buffer = C.Allocate(totalSizeToAlloc
(PathSize)); ImplicitCastExpr *E = new (Buffer) ImplicitCastExpr(T, Kind, Operand, PathSize, VK); if (PathSize) std::uninitialized_copy_n(BasePath->data(), BasePath->size(), E->getTrailingObjects
()); return E; } ImplicitCastExpr *ImplicitCastExpr::CreateEmpty(const ASTContext &C, unsigned PathSize) { void *Buffer = C.Allocate(totalSizeToAlloc
(PathSize)); return new (Buffer) ImplicitCastExpr(EmptyShell(), PathSize); } CStyleCastExpr *CStyleCastExpr::Create(const ASTContext &C, QualType T, ExprValueKind VK, CastKind K, Expr *Op, const CXXCastPath *BasePath, TypeSourceInfo *WrittenTy, SourceLocation L, SourceLocation R) { unsigned PathSize = (BasePath ? BasePath->size() : 0); void *Buffer = C.Allocate(totalSizeToAlloc
(PathSize)); CStyleCastExpr *E = new (Buffer) CStyleCastExpr(T, VK, K, Op, PathSize, WrittenTy, L, R); if (PathSize) std::uninitialized_copy_n(BasePath->data(), BasePath->size(), E->getTrailingObjects
()); return E; } CStyleCastExpr *CStyleCastExpr::CreateEmpty(const ASTContext &C, unsigned PathSize) { void *Buffer = C.Allocate(totalSizeToAlloc
(PathSize)); return new (Buffer) CStyleCastExpr(EmptyShell(), PathSize); } /// getOpcodeStr - Turn an Opcode enum value into the punctuation char it /// corresponds to, e.g. "<<=". StringRef BinaryOperator::getOpcodeStr(Opcode Op) { switch (Op) { #define BINARY_OPERATION(Name, Spelling) case BO_##Name: return Spelling; #include "clang/AST/OperationKinds.def" } llvm_unreachable("Invalid OpCode!"); } BinaryOperatorKind BinaryOperator::getOverloadedOpcode(OverloadedOperatorKind OO) { switch (OO) { default: llvm_unreachable("Not an overloadable binary operator"); case OO_Plus: return BO_Add; case OO_Minus: return BO_Sub; case OO_Star: return BO_Mul; case OO_Slash: return BO_Div; case OO_Percent: return BO_Rem; case OO_Caret: return BO_Xor; case OO_Amp: return BO_And; case OO_Pipe: return BO_Or; case OO_Equal: return BO_Assign; case OO_Less: return BO_LT; case OO_Greater: return BO_GT; case OO_PlusEqual: return BO_AddAssign; case OO_MinusEqual: return BO_SubAssign; case OO_StarEqual: return BO_MulAssign; case OO_SlashEqual: return BO_DivAssign; case OO_PercentEqual: return BO_RemAssign; case OO_CaretEqual: return BO_XorAssign; case OO_AmpEqual: return BO_AndAssign; case OO_PipeEqual: return BO_OrAssign; case OO_LessLess: return BO_Shl; case OO_GreaterGreater: return BO_Shr; case OO_LessLessEqual: return BO_ShlAssign; case OO_GreaterGreaterEqual: return BO_ShrAssign; case OO_EqualEqual: return BO_EQ; case OO_ExclaimEqual: return BO_NE; case OO_LessEqual: return BO_LE; case OO_GreaterEqual: return BO_GE; case OO_AmpAmp: return BO_LAnd; case OO_PipePipe: return BO_LOr; case OO_Comma: return BO_Comma; case OO_ArrowStar: return BO_PtrMemI; } } OverloadedOperatorKind BinaryOperator::getOverloadedOperator(Opcode Opc) { static const OverloadedOperatorKind OverOps[] = { /* .* Cannot be overloaded */OO_None, OO_ArrowStar, OO_Star, OO_Slash, OO_Percent, OO_Plus, OO_Minus, OO_LessLess, OO_GreaterGreater, OO_Less, OO_Greater, OO_LessEqual, OO_GreaterEqual, OO_EqualEqual, OO_ExclaimEqual, OO_Amp, OO_Caret, OO_Pipe, OO_AmpAmp, OO_PipePipe, OO_Equal, OO_StarEqual, OO_SlashEqual, OO_PercentEqual, OO_PlusEqual, OO_MinusEqual, OO_LessLessEqual, OO_GreaterGreaterEqual, OO_AmpEqual, OO_CaretEqual, OO_PipeEqual, OO_Comma }; return OverOps[Opc]; } InitListExpr::InitListExpr(const ASTContext &C, SourceLocation lbraceloc, ArrayRef
initExprs, SourceLocation rbraceloc) : Expr(InitListExprClass, QualType(), VK_RValue, OK_Ordinary, false, false, false, false), InitExprs(C, initExprs.size()), LBraceLoc(lbraceloc), RBraceLoc(rbraceloc), AltForm(nullptr, true) { sawArrayRangeDesignator(false); for (unsigned I = 0; I != initExprs.size(); ++I) { if (initExprs[I]->isTypeDependent()) ExprBits.TypeDependent = true; if (initExprs[I]->isValueDependent()) ExprBits.ValueDependent = true; if (initExprs[I]->isInstantiationDependent()) ExprBits.InstantiationDependent = true; if (initExprs[I]->containsUnexpandedParameterPack()) ExprBits.ContainsUnexpandedParameterPack = true; } InitExprs.insert(C, InitExprs.end(), initExprs.begin(), initExprs.end()); } void InitListExpr::reserveInits(const ASTContext &C, unsigned NumInits) { if (NumInits > InitExprs.size()) InitExprs.reserve(C, NumInits); } void InitListExpr::resizeInits(const ASTContext &C, unsigned NumInits) { InitExprs.resize(C, NumInits, nullptr); } Expr *InitListExpr::updateInit(const ASTContext &C, unsigned Init, Expr *expr) { if (Init >= InitExprs.size()) { InitExprs.insert(C, InitExprs.end(), Init - InitExprs.size() + 1, nullptr); setInit(Init, expr); return nullptr; } Expr *Result = cast_or_null
(InitExprs[Init]); setInit(Init, expr); return Result; } void InitListExpr::setArrayFiller(Expr *filler) { assert(!hasArrayFiller() && "Filler already set!"); ArrayFillerOrUnionFieldInit = filler; // Fill out any "holes" in the array due to designated initializers. Expr **inits = getInits(); for (unsigned i = 0, e = getNumInits(); i != e; ++i) if (inits[i] == nullptr) inits[i] = filler; } bool InitListExpr::isStringLiteralInit() const { if (getNumInits() != 1) return false; const ArrayType *AT = getType()->getAsArrayTypeUnsafe(); if (!AT || !AT->getElementType()->isIntegerType()) return false; // It is possible for getInit() to return null. const Expr *Init = getInit(0); if (!Init) return false; Init = Init->IgnoreParens(); return isa
(Init) || isa
(Init); } SourceLocation InitListExpr::getLocStart() const { if (InitListExpr *SyntacticForm = getSyntacticForm()) return SyntacticForm->getLocStart(); SourceLocation Beg = LBraceLoc; if (Beg.isInvalid()) { // Find the first non-null initializer. for (InitExprsTy::const_iterator I = InitExprs.begin(), E = InitExprs.end(); I != E; ++I) { if (Stmt *S = *I) { Beg = S->getLocStart(); break; } } } return Beg; } SourceLocation InitListExpr::getLocEnd() const { if (InitListExpr *SyntacticForm = getSyntacticForm()) return SyntacticForm->getLocEnd(); SourceLocation End = RBraceLoc; if (End.isInvalid()) { // Find the first non-null initializer from the end. for (InitExprsTy::const_reverse_iterator I = InitExprs.rbegin(), E = InitExprs.rend(); I != E; ++I) { if (Stmt *S = *I) { End = S->getLocEnd(); break; } } } return End; } /// getFunctionType - Return the underlying function type for this block. /// const FunctionProtoType *BlockExpr::getFunctionType() const { // The block pointer is never sugared, but the function type might be. return cast
(getType()) ->getPointeeType()->castAs
(); } SourceLocation BlockExpr::getCaretLocation() const { return TheBlock->getCaretLocation(); } const Stmt *BlockExpr::getBody() const { return TheBlock->getBody(); } Stmt *BlockExpr::getBody() { return TheBlock->getBody(); } //===----------------------------------------------------------------------===// // Generic Expression Routines //===----------------------------------------------------------------------===// /// isUnusedResultAWarning - Return true if this immediate expression should /// be warned about if the result is unused. If so, fill in Loc and Ranges /// with location to warn on and the source range[s] to report with the /// warning. bool Expr::isUnusedResultAWarning(const Expr *&WarnE, SourceLocation &Loc, SourceRange &R1, SourceRange &R2, ASTContext &Ctx) const { // Don't warn if the expr is type dependent. The type could end up // instantiating to void. if (isTypeDependent()) return false; switch (getStmtClass()) { default: if (getType()->isVoidType()) return false; WarnE = this; Loc = getExprLoc(); R1 = getSourceRange(); return true; case ParenExprClass: return cast
(this)->getSubExpr()-> isUnusedResultAWarning(WarnE, Loc, R1, R2, Ctx); case GenericSelectionExprClass: return cast
(this)->getResultExpr()-> isUnusedResultAWarning(WarnE, Loc, R1, R2, Ctx); case ChooseExprClass: return cast
(this)->getChosenSubExpr()-> isUnusedResultAWarning(WarnE, Loc, R1, R2, Ctx); case UnaryOperatorClass: { const UnaryOperator *UO = cast
(this); switch (UO->getOpcode()) { case UO_Plus: case UO_Minus: case UO_AddrOf: case UO_Not: case UO_LNot: case UO_Deref: break; case UO_Coawait: // This is just the 'operator co_await' call inside the guts of a // dependent co_await call. case UO_PostInc: case UO_PostDec: case UO_PreInc: case UO_PreDec: // ++/-- return false; // Not a warning. case UO_Real: case UO_Imag: // accessing a piece of a volatile complex is a side-effect. if (Ctx.getCanonicalType(UO->getSubExpr()->getType()) .isVolatileQualified()) return false; break; case UO_Extension: return UO->getSubExpr()->isUnusedResultAWarning(WarnE, Loc, R1, R2, Ctx); } WarnE = this; Loc = UO->getOperatorLoc(); R1 = UO->getSubExpr()->getSourceRange(); return true; } case BinaryOperatorClass: { const BinaryOperator *BO = cast
(this); switch (BO->getOpcode()) { default: break; // Consider the RHS of comma for side effects. LHS was checked by // Sema::CheckCommaOperands. case BO_Comma: // ((foo =
), 0) is an idiom for hiding the result (and // lvalue-ness) of an assignment written in a macro. if (IntegerLiteral *IE = dyn_cast
(BO->getRHS()->IgnoreParens())) if (IE->getValue() == 0) return false; return BO->getRHS()->isUnusedResultAWarning(WarnE, Loc, R1, R2, Ctx); // Consider '||', '&&' to have side effects if the LHS or RHS does. case BO_LAnd: case BO_LOr: if (!BO->getLHS()->isUnusedResultAWarning(WarnE, Loc, R1, R2, Ctx) || !BO->getRHS()->isUnusedResultAWarning(WarnE, Loc, R1, R2, Ctx)) return false; break; } if (BO->isAssignmentOp()) return false; WarnE = this; Loc = BO->getOperatorLoc(); R1 = BO->getLHS()->getSourceRange(); R2 = BO->getRHS()->getSourceRange(); return true; } case CompoundAssignOperatorClass: case VAArgExprClass: case AtomicExprClass: return false; case ConditionalOperatorClass: { // If only one of the LHS or RHS is a warning, the operator might // be being used for control flow. Only warn if both the LHS and // RHS are warnings. const ConditionalOperator *Exp = cast
(this); if (!Exp->getRHS()->isUnusedResultAWarning(WarnE, Loc, R1, R2, Ctx)) return false; if (!Exp->getLHS()) return true; return Exp->getLHS()->isUnusedResultAWarning(WarnE, Loc, R1, R2, Ctx); } case MemberExprClass: WarnE = this; Loc = cast
(this)->getMemberLoc(); R1 = SourceRange(Loc, Loc); R2 = cast
(this)->getBase()->getSourceRange(); return true; case ArraySubscriptExprClass: WarnE = this; Loc = cast
(this)->getRBracketLoc(); R1 = cast
(this)->getLHS()->getSourceRange(); R2 = cast
(this)->getRHS()->getSourceRange(); return true; case CXXOperatorCallExprClass: { // Warn about operator ==,!=,<,>,<=, and >= even when user-defined operator // overloads as there is no reasonable way to define these such that they // have non-trivial, desirable side-effects. See the -Wunused-comparison // warning: operators == and != are commonly typo'ed, and so warning on them // provides additional value as well. If this list is updated, // DiagnoseUnusedComparison should be as well. const CXXOperatorCallExpr *Op = cast
(this); switch (Op->getOperator()) { default: break; case OO_EqualEqual: case OO_ExclaimEqual: case OO_Less: case OO_Greater: case OO_GreaterEqual: case OO_LessEqual: if (Op->getCallReturnType(Ctx)->isReferenceType() || Op->getCallReturnType(Ctx)->isVoidType()) break; WarnE = this; Loc = Op->getOperatorLoc(); R1 = Op->getSourceRange(); return true; } // Fallthrough for generic call handling. } case CallExprClass: case CXXMemberCallExprClass: case UserDefinedLiteralClass: { // If this is a direct call, get the callee. const CallExpr *CE = cast
(this); if (const Decl *FD = CE->getCalleeDecl()) { const FunctionDecl *Func = dyn_cast
(FD); bool HasWarnUnusedResultAttr = Func ? Func->hasUnusedResultAttr() : FD->hasAttr
(); // If the callee has attribute pure, const, or warn_unused_result, warn // about it. void foo() { strlen("bar"); } should warn. // // Note: If new cases are added here, DiagnoseUnusedExprResult should be // updated to match for QoI. if (HasWarnUnusedResultAttr || FD->hasAttr
() || FD->hasAttr
()) { WarnE = this; Loc = CE->getCallee()->getLocStart(); R1 = CE->getCallee()->getSourceRange(); if (unsigned NumArgs = CE->getNumArgs()) R2 = SourceRange(CE->getArg(0)->getLocStart(), CE->getArg(NumArgs-1)->getLocEnd()); return true; } } return false; } // If we don't know precisely what we're looking at, let's not warn. case UnresolvedLookupExprClass: case CXXUnresolvedConstructExprClass: return false; case CXXTemporaryObjectExprClass: case CXXConstructExprClass: { if (const CXXRecordDecl *Type = getType()->getAsCXXRecordDecl()) { if (Type->hasAttr
()) { WarnE = this; Loc = getLocStart(); R1 = getSourceRange(); return true; } } return false; } case ObjCMessageExprClass: { const ObjCMessageExpr *ME = cast
(this); if (Ctx.getLangOpts().ObjCAutoRefCount && ME->isInstanceMessage() && !ME->getType()->isVoidType() && ME->getMethodFamily() == OMF_init) { WarnE = this; Loc = getExprLoc(); R1 = ME->getSourceRange(); return true; } if (const ObjCMethodDecl *MD = ME->getMethodDecl()) if (MD->hasAttr
()) { WarnE = this; Loc = getExprLoc(); return true; } return false; } case ObjCPropertyRefExprClass: WarnE = this; Loc = getExprLoc(); R1 = getSourceRange(); return true; case PseudoObjectExprClass: { const PseudoObjectExpr *PO = cast
(this); // Only complain about things that have the form of a getter. if (isa
(PO->getSyntacticForm()) || isa
(PO->getSyntacticForm())) return false; WarnE = this; Loc = getExprLoc(); R1 = getSourceRange(); return true; } case StmtExprClass: { // Statement exprs don't logically have side effects themselves, but are // sometimes used in macros in ways that give them a type that is unused. // For example ({ blah; foo(); }) will end up with a type if foo has a type. // however, if the result of the stmt expr is dead, we don't want to emit a // warning. const CompoundStmt *CS = cast
(this)->getSubStmt(); if (!CS->body_empty()) { if (const Expr *E = dyn_cast
(CS->body_back())) return E->isUnusedResultAWarning(WarnE, Loc, R1, R2, Ctx); if (const LabelStmt *Label = dyn_cast
(CS->body_back())) if (const Expr *E = dyn_cast
(Label->getSubStmt())) return E->isUnusedResultAWarning(WarnE, Loc, R1, R2, Ctx); } if (getType()->isVoidType()) return false; WarnE = this; Loc = cast
(this)->getLParenLoc(); R1 = getSourceRange(); return true; } case CXXFunctionalCastExprClass: case CStyleCastExprClass: { // Ignore an explicit cast to void unless the operand is a non-trivial // volatile lvalue. const CastExpr *CE = cast
(this); if (CE->getCastKind() == CK_ToVoid) { if (CE->getSubExpr()->isGLValue() && CE->getSubExpr()->getType().isVolatileQualified()) { const DeclRefExpr *DRE = dyn_cast
(CE->getSubExpr()->IgnoreParens()); if (!(DRE && isa
(DRE->getDecl()) && cast
(DRE->getDecl())->hasLocalStorage())) { return CE->getSubExpr()->isUnusedResultAWarning(WarnE, Loc, R1, R2, Ctx); } } return false; } // If this is a cast to a constructor conversion, check the operand. // Otherwise, the result of the cast is unused. if (CE->getCastKind() == CK_ConstructorConversion) return CE->getSubExpr()->isUnusedResultAWarning(WarnE, Loc, R1, R2, Ctx); WarnE = this; if (const CXXFunctionalCastExpr *CXXCE = dyn_cast
(this)) { Loc = CXXCE->getLocStart(); R1 = CXXCE->getSubExpr()->getSourceRange(); } else { const CStyleCastExpr *CStyleCE = cast
(this); Loc = CStyleCE->getLParenLoc(); R1 = CStyleCE->getSubExpr()->getSourceRange(); } return true; } case ImplicitCastExprClass: { const CastExpr *ICE = cast
(this); // lvalue-to-rvalue conversion on a volatile lvalue is a side-effect. if (ICE->getCastKind() == CK_LValueToRValue && ICE->getSubExpr()->getType().isVolatileQualified()) return false; return ICE->getSubExpr()->isUnusedResultAWarning(WarnE, Loc, R1, R2, Ctx); } case CXXDefaultArgExprClass: return (cast
(this) ->getExpr()->isUnusedResultAWarning(WarnE, Loc, R1, R2, Ctx)); case CXXDefaultInitExprClass: return (cast
(this) ->getExpr()->isUnusedResultAWarning(WarnE, Loc, R1, R2, Ctx)); case CXXNewExprClass: // FIXME: In theory, there might be new expressions that don't have side // effects (e.g. a placement new with an uninitialized POD). case CXXDeleteExprClass: return false; case CXXBindTemporaryExprClass: return (cast
(this) ->getSubExpr()->isUnusedResultAWarning(WarnE, Loc, R1, R2, Ctx)); case ExprWithCleanupsClass: return (cast
(this) ->getSubExpr()->isUnusedResultAWarning(WarnE, Loc, R1, R2, Ctx)); } } /// isOBJCGCCandidate - Check if an expression is objc gc'able. /// returns true, if it is; false otherwise. bool Expr::isOBJCGCCandidate(ASTContext &Ctx) const { const Expr *E = IgnoreParens(); switch (E->getStmtClass()) { default: return false; case ObjCIvarRefExprClass: return true; case Expr::UnaryOperatorClass: return cast
(E)->getSubExpr()->isOBJCGCCandidate(Ctx); case ImplicitCastExprClass: return cast
(E)->getSubExpr()->isOBJCGCCandidate(Ctx); case MaterializeTemporaryExprClass: return cast
(E)->GetTemporaryExpr() ->isOBJCGCCandidate(Ctx); case CStyleCastExprClass: return cast
(E)->getSubExpr()->isOBJCGCCandidate(Ctx); case DeclRefExprClass: { const Decl *D = cast
(E)->getDecl(); if (const VarDecl *VD = dyn_cast
(D)) { if (VD->hasGlobalStorage()) return true; QualType T = VD->getType(); // dereferencing to a pointer is always a gc'able candidate, // unless it is __weak. return T->isPointerType() && (Ctx.getObjCGCAttrKind(T) != Qualifiers::Weak); } return false; } case MemberExprClass: { const MemberExpr *M = cast
(E); return M->getBase()->isOBJCGCCandidate(Ctx); } case ArraySubscriptExprClass: return cast
(E)->getBase()->isOBJCGCCandidate(Ctx); } } bool Expr::isBoundMemberFunction(ASTContext &Ctx) const { if (isTypeDependent()) return false; return ClassifyLValue(Ctx) == Expr::LV_MemberFunction; } QualType Expr::findBoundMemberType(const Expr *expr) { assert(expr->hasPlaceholderType(BuiltinType::BoundMember)); // Bound member expressions are always one of these possibilities: // x->m x.m x->*y x.*y // (possibly parenthesized) expr = expr->IgnoreParens(); if (const MemberExpr *mem = dyn_cast
(expr)) { assert(isa
(mem->getMemberDecl())); return mem->getMemberDecl()->getType(); } if (const BinaryOperator *op = dyn_cast
(expr)) { QualType type = op->getRHS()->getType()->castAs
() ->getPointeeType(); assert(type->isFunctionType()); return type; } assert(isa
(expr) || isa
(expr)); return QualType(); } Expr* Expr::IgnoreParens() { Expr* E = this; while (true) { if (ParenExpr* P = dyn_cast
(E)) { E = P->getSubExpr(); continue; } if (UnaryOperator* P = dyn_cast
(E)) { if (P->getOpcode() == UO_Extension) { E = P->getSubExpr(); continue; } } if (GenericSelectionExpr* P = dyn_cast
(E)) { if (!P->isResultDependent()) { E = P->getResultExpr(); continue; } } if (ChooseExpr* P = dyn_cast
(E)) { if (!P->isConditionDependent()) { E = P->getChosenSubExpr(); continue; } } return E; } } /// IgnoreParenCasts - Ignore parentheses and casts. Strip off any ParenExpr /// or CastExprs or ImplicitCastExprs, returning their operand. Expr *Expr::IgnoreParenCasts() { Expr *E = this; while (true) { E = E->IgnoreParens(); if (CastExpr *P = dyn_cast
(E)) { E = P->getSubExpr(); continue; } if (MaterializeTemporaryExpr *Materialize = dyn_cast
(E)) { E = Materialize->GetTemporaryExpr(); continue; } if (SubstNonTypeTemplateParmExpr *NTTP = dyn_cast
(E)) { E = NTTP->getReplacement(); continue; } return E; } } Expr *Expr::IgnoreCasts() { Expr *E = this; while (true) { if (CastExpr *P = dyn_cast
(E)) { E = P->getSubExpr(); continue; } if (MaterializeTemporaryExpr *Materialize = dyn_cast
(E)) { E = Materialize->GetTemporaryExpr(); continue; } if (SubstNonTypeTemplateParmExpr *NTTP = dyn_cast
(E)) { E = NTTP->getReplacement(); continue; } return E; } } /// IgnoreParenLValueCasts - Ignore parentheses and lvalue-to-rvalue /// casts. This is intended purely as a temporary workaround for code /// that hasn't yet been rewritten to do the right thing about those /// casts, and may disappear along with the last internal use. Expr *Expr::IgnoreParenLValueCasts() { Expr *E = this; while (true) { E = E->IgnoreParens(); if (CastExpr *P = dyn_cast
(E)) { if (P->getCastKind() == CK_LValueToRValue) { E = P->getSubExpr(); continue; } } else if (MaterializeTemporaryExpr *Materialize = dyn_cast
(E)) { E = Materialize->GetTemporaryExpr(); continue; } else if (SubstNonTypeTemplateParmExpr *NTTP = dyn_cast
(E)) { E = NTTP->getReplacement(); continue; } break; } return E; } Expr *Expr::ignoreParenBaseCasts() { Expr *E = this; while (true) { E = E->IgnoreParens(); if (CastExpr *CE = dyn_cast
(E)) { if (CE->getCastKind() == CK_DerivedToBase || CE->getCastKind() == CK_UncheckedDerivedToBase || CE->getCastKind() == CK_NoOp) { E = CE->getSubExpr(); continue; } } return E; } } Expr *Expr::IgnoreParenImpCasts() { Expr *E = this; while (true) { E = E->IgnoreParens(); if (ImplicitCastExpr *P = dyn_cast
(E)) { E = P->getSubExpr(); continue; } if (MaterializeTemporaryExpr *Materialize = dyn_cast
(E)) { E = Materialize->GetTemporaryExpr(); continue; } if (SubstNonTypeTemplateParmExpr *NTTP = dyn_cast
(E)) { E = NTTP->getReplacement(); continue; } return E; } } Expr *Expr::IgnoreConversionOperator() { if (CXXMemberCallExpr *MCE = dyn_cast
(this)) { if (MCE->getMethodDecl() && isa
(MCE->getMethodDecl())) return MCE->getImplicitObjectArgument(); } return this; } /// IgnoreParenNoopCasts - Ignore parentheses and casts that do not change the /// value (including ptr->int casts of the same size). Strip off any /// ParenExpr or CastExprs, returning their operand. Expr *Expr::IgnoreParenNoopCasts(ASTContext &Ctx) { Expr *E = this; while (true) { E = E->IgnoreParens(); if (CastExpr *P = dyn_cast
(E)) { // We ignore integer <-> casts that are of the same width, ptr<->ptr and // ptr<->int casts of the same width. We also ignore all identity casts. Expr *SE = P->getSubExpr(); if (Ctx.hasSameUnqualifiedType(E->getType(), SE->getType())) { E = SE; continue; } if ((E->getType()->isPointerType() || E->getType()->isIntegralType(Ctx)) && (SE->getType()->isPointerType() || SE->getType()->isIntegralType(Ctx)) && Ctx.getTypeSize(E->getType()) == Ctx.getTypeSize(SE->getType())) { E = SE; continue; } } if (SubstNonTypeTemplateParmExpr *NTTP = dyn_cast
(E)) { E = NTTP->getReplacement(); continue; } return E; } } bool Expr::isDefaultArgument() const { const Expr *E = this; if (const MaterializeTemporaryExpr *M = dyn_cast
(E)) E = M->GetTemporaryExpr(); while (const ImplicitCastExpr *ICE = dyn_cast
(E)) E = ICE->getSubExprAsWritten(); return isa
(E); } /// \brief Skip over any no-op casts and any temporary-binding /// expressions. static const Expr *skipTemporaryBindingsNoOpCastsAndParens(const Expr *E) { if (const MaterializeTemporaryExpr *M = dyn_cast
(E)) E = M->GetTemporaryExpr(); while (const ImplicitCastExpr *ICE = dyn_cast
(E)) { if (ICE->getCastKind() == CK_NoOp) E = ICE->getSubExpr(); else break; } while (const CXXBindTemporaryExpr *BE = dyn_cast
(E)) E = BE->getSubExpr(); while (const ImplicitCastExpr *ICE = dyn_cast
(E)) { if (ICE->getCastKind() == CK_NoOp) E = ICE->getSubExpr(); else break; } return E->IgnoreParens(); } /// isTemporaryObject - Determines if this expression produces a /// temporary of the given class type. bool Expr::isTemporaryObject(ASTContext &C, const CXXRecordDecl *TempTy) const { if (!C.hasSameUnqualifiedType(getType(), C.getTypeDeclType(TempTy))) return false; const Expr *E = skipTemporaryBindingsNoOpCastsAndParens(this); // Temporaries are by definition pr-values of class type. if (!E->Classify(C).isPRValue()) { // In this context, property reference is a message call and is pr-value. if (!isa
(E)) return false; } // Black-list a few cases which yield pr-values of class type that don't // refer to temporaries of that type: // - implicit derived-to-base conversions if (isa
(E)) { switch (cast
(E)->getCastKind()) { case CK_DerivedToBase: case CK_UncheckedDerivedToBase: return false; default: break; } } // - member expressions (all) if (isa
(E)) return false; if (const BinaryOperator *BO = dyn_cast
(E)) if (BO->isPtrMemOp()) return false; // - opaque values (all) if (isa
(E)) return false; return true; } bool Expr::isImplicitCXXThis() const { const Expr *E = this; // Strip away parentheses and casts we don't care about. while (true) { if (const ParenExpr *Paren = dyn_cast
(E)) { E = Paren->getSubExpr(); continue; } if (const ImplicitCastExpr *ICE = dyn_cast
(E)) { if (ICE->getCastKind() == CK_NoOp || ICE->getCastKind() == CK_LValueToRValue || ICE->getCastKind() == CK_DerivedToBase || ICE->getCastKind() == CK_UncheckedDerivedToBase) { E = ICE->getSubExpr(); continue; } } if (const UnaryOperator* UnOp = dyn_cast
(E)) { if (UnOp->getOpcode() == UO_Extension) { E = UnOp->getSubExpr(); continue; } } if (const MaterializeTemporaryExpr *M = dyn_cast
(E)) { E = M->GetTemporaryExpr(); continue; } break; } if (const CXXThisExpr *This = dyn_cast
(E)) return This->isImplicit(); return false; } /// hasAnyTypeDependentArguments - Determines if any of the expressions /// in Exprs is type-dependent. bool Expr::hasAnyTypeDependentArguments(ArrayRef
Exprs) { for (unsigned I = 0; I < Exprs.size(); ++I) if (Exprs[I]->isTypeDependent()) return true; return false; } bool Expr::isConstantInitializer(ASTContext &Ctx, bool IsForRef, const Expr **Culprit) const { // This function is attempting whether an expression is an initializer // which can be evaluated at compile-time. It very closely parallels // ConstExprEmitter in CGExprConstant.cpp; if they don't match, it // will lead to unexpected results. Like ConstExprEmitter, it falls back // to isEvaluatable most of the time. // // If we ever capture reference-binding directly in the AST, we can // kill the second parameter. if (IsForRef) { EvalResult Result; if (EvaluateAsLValue(Result, Ctx) && !Result.HasSideEffects) return true; if (Culprit) *Culprit = this; return false; } switch (getStmtClass()) { default: break; case StringLiteralClass: case ObjCEncodeExprClass: return true; case CXXTemporaryObjectExprClass: case CXXConstructExprClass: { const CXXConstructExpr *CE = cast
(this); if (CE->getConstructor()->isTrivial() && CE->getConstructor()->getParent()->hasTrivialDestructor()) { // Trivial default constructor if (!CE->getNumArgs()) return true; // Trivial copy constructor assert(CE->getNumArgs() == 1 && "trivial ctor with > 1 argument"); return CE->getArg(0)->isConstantInitializer(Ctx, false, Culprit); } break; } case CompoundLiteralExprClass: { // This handles gcc's extension that allows global initializers like // "struct x {int x;} x = (struct x) {};". // FIXME: This accepts other cases it shouldn't! const Expr *Exp = cast
(this)->getInitializer(); return Exp->isConstantInitializer(Ctx, false, Culprit); } case DesignatedInitUpdateExprClass: { const DesignatedInitUpdateExpr *DIUE = cast
(this); return DIUE->getBase()->isConstantInitializer(Ctx, false, Culprit) && DIUE->getUpdater()->isConstantInitializer(Ctx, false, Culprit); } case InitListExprClass: { const InitListExpr *ILE = cast
(this); if (ILE->getType()->isArrayType()) { unsigned numInits = ILE->getNumInits(); for (unsigned i = 0; i < numInits; i++) { if (!ILE->getInit(i)->isConstantInitializer(Ctx, false, Culprit)) return false; } return true; } if (ILE->getType()->isRecordType()) { unsigned ElementNo = 0; RecordDecl *RD = ILE->getType()->getAs
()->getDecl(); for (const auto *Field : RD->fields()) { // If this is a union, skip all the fields that aren't being initialized. if (RD->isUnion() && ILE->getInitializedFieldInUnion() != Field) continue; // Don't emit anonymous bitfields, they just affect layout. if (Field->isUnnamedBitfield()) continue; if (ElementNo < ILE->getNumInits()) { const Expr *Elt = ILE->getInit(ElementNo++); if (Field->isBitField()) { // Bitfields have to evaluate to an integer. llvm::APSInt ResultTmp; if (!Elt->EvaluateAsInt(ResultTmp, Ctx)) { if (Culprit) *Culprit = Elt; return false; } } else { bool RefType = Field->getType()->isReferenceType(); if (!Elt->isConstantInitializer(Ctx, RefType, Culprit)) return false; } } } return true; } break; } case ImplicitValueInitExprClass: case NoInitExprClass: return true; case ParenExprClass: return cast
(this)->getSubExpr() ->isConstantInitializer(Ctx, IsForRef, Culprit); case GenericSelectionExprClass: return cast
(this)->getResultExpr() ->isConstantInitializer(Ctx, IsForRef, Culprit); case ChooseExprClass: if (cast
(this)->isConditionDependent()) { if (Culprit) *Culprit = this; return false; } return cast
(this)->getChosenSubExpr() ->isConstantInitializer(Ctx, IsForRef, Culprit); case UnaryOperatorClass: { const UnaryOperator* Exp = cast
(this); if (Exp->getOpcode() == UO_Extension) return Exp->getSubExpr()->isConstantInitializer(Ctx, false, Culprit); break; } case CXXFunctionalCastExprClass: case CXXStaticCastExprClass: case ImplicitCastExprClass: case CStyleCastExprClass: case ObjCBridgedCastExprClass: case CXXDynamicCastExprClass: case CXXReinterpretCastExprClass: case CXXConstCastExprClass: { const CastExpr *CE = cast
(this); // Handle misc casts we want to ignore. if (CE->getCastKind() == CK_NoOp || CE->getCastKind() == CK_LValueToRValue || CE->getCastKind() == CK_ToUnion || CE->getCastKind() == CK_ConstructorConversion || CE->getCastKind() == CK_NonAtomicToAtomic || CE->getCastKind() == CK_AtomicToNonAtomic) return CE->getSubExpr()->isConstantInitializer(Ctx, false, Culprit); break; } case MaterializeTemporaryExprClass: return cast
(this)->GetTemporaryExpr() ->isConstantInitializer(Ctx, false, Culprit); case SubstNonTypeTemplateParmExprClass: return cast
(this)->getReplacement() ->isConstantInitializer(Ctx, false, Culprit); case CXXDefaultArgExprClass: return cast
(this)->getExpr() ->isConstantInitializer(Ctx, false, Culprit); case CXXDefaultInitExprClass: return cast
(this)->getExpr() ->isConstantInitializer(Ctx, false, Culprit); } // Allow certain forms of UB in constant initializers: signed integer // overflow and floating-point division by zero. We'll give a warning on // these, but they're common enough that we have to accept them. if (isEvaluatable(Ctx, SE_AllowUndefinedBehavior)) return true; if (Culprit) *Culprit = this; return false; } namespace { /// \brief Look for any side effects within a Stmt. class SideEffectFinder : public ConstEvaluatedExprVisitor
{ typedef ConstEvaluatedExprVisitor
Inherited; const bool IncludePossibleEffects; bool HasSideEffects; public: explicit SideEffectFinder(const ASTContext &Context, bool IncludePossible) : Inherited(Context), IncludePossibleEffects(IncludePossible), HasSideEffects(false) { } bool hasSideEffects() const { return HasSideEffects; } void VisitExpr(const Expr *E) { if (!HasSideEffects && E->HasSideEffects(Context, IncludePossibleEffects)) HasSideEffects = true; } }; } bool Expr::HasSideEffects(const ASTContext &Ctx, bool IncludePossibleEffects) const { // In circumstances where we care about definite side effects instead of // potential side effects, we want to ignore expressions that are part of a // macro expansion as a potential side effect. if (!IncludePossibleEffects && getExprLoc().isMacroID()) return false; if (isInstantiationDependent()) return IncludePossibleEffects; switch (getStmtClass()) { case NoStmtClass: #define ABSTRACT_STMT(Type) #define STMT(Type, Base) case Type##Class: #define EXPR(Type, Base) #include "clang/AST/StmtNodes.inc" llvm_unreachable("unexpected Expr kind"); case DependentScopeDeclRefExprClass: case CXXUnresolvedConstructExprClass: case CXXDependentScopeMemberExprClass: case UnresolvedLookupExprClass: case UnresolvedMemberExprClass: case PackExpansionExprClass: case SubstNonTypeTemplateParmPackExprClass: case FunctionParmPackExprClass: case TypoExprClass: case CXXFoldExprClass: llvm_unreachable("shouldn't see dependent / unresolved nodes here"); case DeclRefExprClass: case ObjCIvarRefExprClass: case PredefinedExprClass: case IntegerLiteralClass: case FloatingLiteralClass: case ImaginaryLiteralClass: case StringLiteralClass: case CharacterLiteralClass: case OffsetOfExprClass: case ImplicitValueInitExprClass: case UnaryExprOrTypeTraitExprClass: case AddrLabelExprClass: case GNUNullExprClass: case NoInitExprClass: case CXXBoolLiteralExprClass: case CXXNullPtrLiteralExprClass: case CXXThisExprClass: case CXXScalarValueInitExprClass: case TypeTraitExprClass: case ArrayTypeTraitExprClass: case ExpressionTraitExprClass: case CXXNoexceptExprClass: case SizeOfPackExprClass: case ObjCStringLiteralClass: case ObjCEncodeExprClass: case ObjCBoolLiteralExprClass: case CXXUuidofExprClass: case OpaqueValueExprClass: // These never have a side-effect. return false; case CallExprClass: case CXXOperatorCallExprClass: case CXXMemberCallExprClass: case CUDAKernelCallExprClass: case UserDefinedLiteralClass: { // We don't know a call definitely has side effects, except for calls // to pure/const functions that definitely don't. // If the call itself is considered side-effect free, check the operands. const Decl *FD = cast
(this)->getCalleeDecl(); bool IsPure = FD && (FD->hasAttr
() || FD->hasAttr
()); if (IsPure || !IncludePossibleEffects) break; return true; } case BlockExprClass: case CXXBindTemporaryExprClass: if (!IncludePossibleEffects) break; return true; case MSPropertyRefExprClass: case MSPropertySubscriptExprClass: case CompoundAssignOperatorClass: case VAArgExprClass: case AtomicExprClass: case CXXThrowExprClass: case CXXNewExprClass: case CXXDeleteExprClass: case CoawaitExprClass: case CoyieldExprClass: // These always have a side-effect. return true; case StmtExprClass: { // StmtExprs have a side-effect if any substatement does. SideEffectFinder Finder(Ctx, IncludePossibleEffects); Finder.Visit(cast
(this)->getSubStmt()); return Finder.hasSideEffects(); } case ExprWithCleanupsClass: if (IncludePossibleEffects) if (cast
(this)->cleanupsHaveSideEffects()) return true; break; case ParenExprClass: case ArraySubscriptExprClass: case OMPArraySectionExprClass: case MemberExprClass: case ConditionalOperatorClass: case BinaryConditionalOperatorClass: case CompoundLiteralExprClass: case ExtVectorElementExprClass: case DesignatedInitExprClass: case DesignatedInitUpdateExprClass: case ParenListExprClass: case CXXPseudoDestructorExprClass: case CXXStdInitializerListExprClass: case SubstNonTypeTemplateParmExprClass: case MaterializeTemporaryExprClass: case ShuffleVectorExprClass: case ConvertVectorExprClass: case AsTypeExprClass: // These have a side-effect if any subexpression does. break; case UnaryOperatorClass: if (cast
(this)->isIncrementDecrementOp()) return true; break; case BinaryOperatorClass: if (cast
(this)->isAssignmentOp()) return true; break; case InitListExprClass: // FIXME: The children for an InitListExpr doesn't include the array filler. if (const Expr *E = cast
(this)->getArrayFiller()) if (E->HasSideEffects(Ctx, IncludePossibleEffects)) return true; break; case GenericSelectionExprClass: return cast
(this)->getResultExpr()-> HasSideEffects(Ctx, IncludePossibleEffects); case ChooseExprClass: return cast
(this)->getChosenSubExpr()->HasSideEffects( Ctx, IncludePossibleEffects); case CXXDefaultArgExprClass: return cast
(this)->getExpr()->HasSideEffects( Ctx, IncludePossibleEffects); case CXXDefaultInitExprClass: { const FieldDecl *FD = cast
(this)->getField(); if (const Expr *E = FD->getInClassInitializer()) return E->HasSideEffects(Ctx, IncludePossibleEffects); // If we've not yet parsed the initializer, assume it has side-effects. return true; } case CXXDynamicCastExprClass: { // A dynamic_cast expression has side-effects if it can throw. const CXXDynamicCastExpr *DCE = cast
(this); if (DCE->getTypeAsWritten()->isReferenceType() && DCE->getCastKind() == CK_Dynamic) return true; } // Fall through. case ImplicitCastExprClass: case CStyleCastExprClass: case CXXStaticCastExprClass: case CXXReinterpretCastExprClass: case CXXConstCastExprClass: case CXXFunctionalCastExprClass: { // While volatile reads are side-effecting in both C and C++, we treat them // as having possible (not definite) side-effects. This allows idiomatic // code to behave without warning, such as sizeof(*v) for a volatile- // qualified pointer. if (!IncludePossibleEffects) break; const CastExpr *CE = cast
(this); if (CE->getCastKind() == CK_LValueToRValue && CE->getSubExpr()->getType().isVolatileQualified()) return true; break; } case CXXTypeidExprClass: // typeid might throw if its subexpression is potentially-evaluated, so has // side-effects in that case whether or not its subexpression does. return cast