diff options
Diffstat (limited to 'lib/AST/ExprConstant.cpp')
-rw-r--r-- | lib/AST/ExprConstant.cpp | 242 |
1 files changed, 106 insertions, 136 deletions
diff --git a/lib/AST/ExprConstant.cpp b/lib/AST/ExprConstant.cpp index 4d0805323e568..75bb0cac51b83 100644 --- a/lib/AST/ExprConstant.cpp +++ b/lib/AST/ExprConstant.cpp @@ -148,8 +148,7 @@ namespace { static unsigned findMostDerivedSubobject(ASTContext &Ctx, APValue::LValueBase Base, ArrayRef<APValue::LValuePathEntry> Path, - uint64_t &ArraySize, QualType &Type, bool &IsArray, - bool &IsUnsizedArray) { + uint64_t &ArraySize, QualType &Type, bool &IsArray) { // This only accepts LValueBases from APValues, and APValues don't support // arrays that lack size info. assert(!isBaseAnAllocSizeCall(Base) && @@ -158,34 +157,28 @@ namespace { Type = getType(Base); for (unsigned I = 0, N = Path.size(); I != N; ++I) { - if (auto AT = Ctx.getAsArrayType(Type)) { + if (Type->isArrayType()) { + const ConstantArrayType *CAT = + cast<ConstantArrayType>(Ctx.getAsArrayType(Type)); + Type = CAT->getElementType(); + ArraySize = CAT->getSize().getZExtValue(); MostDerivedLength = I + 1; IsArray = true; - if (auto CAT = Ctx.getAsConstantArrayType(Type)) - ArraySize = CAT->getSize().getZExtValue(); - else { - ArraySize = 0; - IsUnsizedArray = true; - } - Type = AT->getElementType(); } else if (Type->isAnyComplexType()) { const ComplexType *CT = Type->castAs<ComplexType>(); Type = CT->getElementType(); ArraySize = 2; MostDerivedLength = I + 1; IsArray = true; - IsUnsizedArray = false; } else if (const FieldDecl *FD = getAsField(Path[I])) { Type = FD->getType(); ArraySize = 0; MostDerivedLength = I + 1; IsArray = false; - IsUnsizedArray = false; } else { // Path[I] describes a base class. ArraySize = 0; IsArray = false; - IsUnsizedArray = false; } } return MostDerivedLength; @@ -207,9 +200,8 @@ namespace { /// Is this a pointer one past the end of an object? unsigned IsOnePastTheEnd : 1; - /// Indicator of whether the most-derived object is an unsized array (e.g. - /// of unknown bound). - unsigned MostDerivedIsAnUnsizedArray : 1; + /// Indicator of whether the first entry is an unsized array. + unsigned FirstEntryIsAnUnsizedArray : 1; /// Indicator of whether the most-derived object is an array element. unsigned MostDerivedIsArrayElement : 1; @@ -239,28 +231,25 @@ namespace { explicit SubobjectDesignator(QualType T) : Invalid(false), IsOnePastTheEnd(false), - MostDerivedIsAnUnsizedArray(false), MostDerivedIsArrayElement(false), + FirstEntryIsAnUnsizedArray(false), MostDerivedIsArrayElement(false), MostDerivedPathLength(0), MostDerivedArraySize(0), MostDerivedType(T) {} SubobjectDesignator(ASTContext &Ctx, const APValue &V) : Invalid(!V.isLValue() || !V.hasLValuePath()), IsOnePastTheEnd(false), - MostDerivedIsAnUnsizedArray(false), MostDerivedIsArrayElement(false), + FirstEntryIsAnUnsizedArray(false), MostDerivedIsArrayElement(false), MostDerivedPathLength(0), MostDerivedArraySize(0) { assert(V.isLValue() && "Non-LValue used to make an LValue designator?"); if (!Invalid) { IsOnePastTheEnd = V.isLValueOnePastTheEnd(); ArrayRef<PathEntry> VEntries = V.getLValuePath(); Entries.insert(Entries.end(), VEntries.begin(), VEntries.end()); - if (auto Base = V.getLValueBase()) { - if (auto Decl = Base.dyn_cast<ValueDecl const*>()) - Base = cast<ValueDecl>(Decl->getMostRecentDecl()); - bool IsArray = false, IsUnsizedArray = false; + if (V.getLValueBase()) { + bool IsArray = false; MostDerivedPathLength = findMostDerivedSubobject( - Ctx, Base, V.getLValuePath(), MostDerivedArraySize, - MostDerivedType, IsArray, IsUnsizedArray); - MostDerivedIsArrayElement = IsArray; - MostDerivedIsAnUnsizedArray = IsUnsizedArray; + Ctx, V.getLValueBase(), V.getLValuePath(), MostDerivedArraySize, + MostDerivedType, IsArray); + MostDerivedIsArrayElement = IsArray; } } } @@ -274,7 +263,7 @@ namespace { /// known bound. bool isMostDerivedAnUnsizedArray() const { assert(!Invalid && "Calling this makes no sense on invalid designators"); - return MostDerivedIsAnUnsizedArray; + return Entries.size() == 1 && FirstEntryIsAnUnsizedArray; } /// Determine what the most derived array's size is. Results in an assertion @@ -314,7 +303,6 @@ namespace { // This is a most-derived object. MostDerivedType = CAT->getElementType(); MostDerivedIsArrayElement = true; - MostDerivedIsAnUnsizedArray = false; MostDerivedArraySize = CAT->getSize().getZExtValue(); MostDerivedPathLength = Entries.size(); } @@ -327,7 +315,6 @@ namespace { MostDerivedType = ElemTy; MostDerivedIsArrayElement = true; - MostDerivedIsAnUnsizedArray = true; // The value in MostDerivedArraySize is undefined in this case. So, set it // to an arbitrary value that's likely to loudly break things if it's // used. @@ -346,7 +333,6 @@ namespace { if (const FieldDecl *FD = dyn_cast<FieldDecl>(D)) { MostDerivedType = FD->getType(); MostDerivedIsArrayElement = false; - MostDerivedIsAnUnsizedArray = false; MostDerivedArraySize = 0; MostDerivedPathLength = Entries.size(); } @@ -361,14 +347,53 @@ namespace { // is unlikely to matter. MostDerivedType = EltTy; MostDerivedIsArrayElement = true; - MostDerivedIsAnUnsizedArray = false; MostDerivedArraySize = 2; MostDerivedPathLength = Entries.size(); } void diagnosePointerArithmetic(EvalInfo &Info, const Expr *E, const APSInt &N); /// Add N to the address of this subobject. - void adjustIndex(EvalInfo &Info, const Expr *E, APSInt N); + void adjustIndex(EvalInfo &Info, const Expr *E, APSInt N) { + if (Invalid || !N) return; + uint64_t TruncatedN = N.extOrTrunc(64).getZExtValue(); + if (isMostDerivedAnUnsizedArray()) { + // Can't verify -- trust that the user is doing the right thing (or if + // not, trust that the caller will catch the bad behavior). + // FIXME: Should we reject if this overflows, at least? + Entries.back().ArrayIndex += TruncatedN; + return; + } + + // [expr.add]p4: For the purposes of these operators, a pointer to a + // nonarray object behaves the same as a pointer to the first element of + // an array of length one with the type of the object as its element type. + bool IsArray = MostDerivedPathLength == Entries.size() && + MostDerivedIsArrayElement; + uint64_t ArrayIndex = + IsArray ? Entries.back().ArrayIndex : (uint64_t)IsOnePastTheEnd; + uint64_t ArraySize = + IsArray ? getMostDerivedArraySize() : (uint64_t)1; + + if (N < -(int64_t)ArrayIndex || N > ArraySize - ArrayIndex) { + // Calculate the actual index in a wide enough type, so we can include + // it in the note. + N = N.extend(std::max<unsigned>(N.getBitWidth() + 1, 65)); + (llvm::APInt&)N += ArrayIndex; + assert(N.ugt(ArraySize) && "bounds check failed for in-bounds index"); + diagnosePointerArithmetic(Info, E, N); + setInvalid(); + return; + } + + ArrayIndex += TruncatedN; + assert(ArrayIndex <= ArraySize && + "bounds check succeeded for out-of-bounds index"); + + if (IsArray) + Entries.back().ArrayIndex = ArrayIndex; + else + IsOnePastTheEnd = (ArrayIndex != 0); + } }; /// A stack frame in the constexpr call stack. @@ -470,7 +495,7 @@ namespace { // FIXME: Force the precision of the source value down so we don't // print digits which are usually useless (we don't really care here if // we truncate a digit by accident in edge cases). Ideally, - // APFloat::toString would automatically print the shortest + // APFloat::toString would automatically print the shortest // representation which rounds to the correct value, but it's a bit // tricky to implement. unsigned precision = @@ -695,7 +720,7 @@ namespace { private: OptionalDiagnostic Diag(SourceLocation Loc, diag::kind DiagId, unsigned ExtraNotes, bool IsCCEDiag) { - + if (EvalStatus.Diag) { // If we have a prior diagnostic, it will be noting that the expression // isn't a constant expression. This diagnostic is more important, @@ -748,7 +773,7 @@ namespace { unsigned ExtraNotes = 0) { return Diag(Loc, DiagId, ExtraNotes, false); } - + OptionalDiagnostic FFDiag(const Expr *E, diag::kind DiagId = diag::note_invalid_subexpr_in_const_expr, unsigned ExtraNotes = 0) { @@ -1061,53 +1086,6 @@ void SubobjectDesignator::diagnosePointerArithmetic(EvalInfo &Info, setInvalid(); } -void SubobjectDesignator::adjustIndex(EvalInfo &Info, const Expr *E, APSInt N) { - if (Invalid || !N) return; - - uint64_t TruncatedN = N.extOrTrunc(64).getZExtValue(); - if (isMostDerivedAnUnsizedArray()) { - // If we're dealing with an array without constant bound, the expression is - // not a constant expression. - if (!Info.checkingPotentialConstantExpression()) - Info.CCEDiag(E, diag::note_constexpr_array_unknown_bound_arithmetic); - // Can't verify -- trust that the user is doing the right thing (or if - // not, trust that the caller will catch the bad behavior). - // FIXME: Should we reject if this overflows, at least? - Entries.back().ArrayIndex += TruncatedN; - return; - } - - // [expr.add]p4: For the purposes of these operators, a pointer to a - // nonarray object behaves the same as a pointer to the first element of - // an array of length one with the type of the object as its element type. - bool IsArray = MostDerivedPathLength == Entries.size() && - MostDerivedIsArrayElement; - uint64_t ArrayIndex = - IsArray ? Entries.back().ArrayIndex : (uint64_t)IsOnePastTheEnd; - uint64_t ArraySize = - IsArray ? getMostDerivedArraySize() : (uint64_t)1; - - if (N < -(int64_t)ArrayIndex || N > ArraySize - ArrayIndex) { - // Calculate the actual index in a wide enough type, so we can include - // it in the note. - N = N.extend(std::max<unsigned>(N.getBitWidth() + 1, 65)); - (llvm::APInt&)N += ArrayIndex; - assert(N.ugt(ArraySize) && "bounds check failed for in-bounds index"); - diagnosePointerArithmetic(Info, E, N); - setInvalid(); - return; - } - - ArrayIndex += TruncatedN; - assert(ArrayIndex <= ArraySize && - "bounds check succeeded for out-of-bounds index"); - - if (IsArray) - Entries.back().ArrayIndex = ArrayIndex; - else - IsOnePastTheEnd = (ArrayIndex != 0); -} - CallStackFrame::CallStackFrame(EvalInfo &Info, SourceLocation CallLoc, const FunctionDecl *Callee, const LValue *This, APValue *Arguments) @@ -1236,6 +1214,8 @@ namespace { IsNullPtr); else { assert(!InvalidBase && "APValues can't handle invalid LValue bases"); + assert(!Designator.FirstEntryIsAnUnsizedArray && + "Unsized array with a valid base?"); V = APValue(Base, Offset, Designator.Entries, Designator.IsOnePastTheEnd, CallIndex, IsNullPtr); } @@ -1300,9 +1280,12 @@ namespace { if (checkSubobject(Info, E, isa<FieldDecl>(D) ? CSK_Field : CSK_Base)) Designator.addDeclUnchecked(D, Virtual); } - void addUnsizedArray(EvalInfo &Info, const Expr *E, QualType ElemTy) { - if (checkSubobject(Info, E, CSK_ArrayToPointer)) - Designator.addUnsizedArrayUnchecked(ElemTy); + void addUnsizedArray(EvalInfo &Info, QualType ElemTy) { + assert(Designator.Entries.empty() && getType(Base)->isPointerType()); + assert(isBaseAnAllocSizeCall(Base) && + "Only alloc_size bases can have unsized arrays"); + Designator.FirstEntryIsAnUnsizedArray = true; + Designator.addUnsizedArrayUnchecked(ElemTy); } void addArray(EvalInfo &Info, const Expr *E, const ConstantArrayType *CAT) { if (checkSubobject(Info, E, CSK_ArrayToPointer)) @@ -3033,15 +3016,6 @@ static CompleteObject findCompleteObject(EvalInfo &Info, const Expr *E, if (!evaluateVarDeclInit(Info, E, VD, Frame, BaseVal)) return CompleteObject(); - - // The complete object can be an array of unknown bound, in which case we - // have to find the most recent declaration and adjust the type accordingly. - if (Info.Ctx.getAsIncompleteArrayType(BaseType)) { - QualType MostRecentType = - cast<ValueDecl const>(D->getMostRecentDecl())->getType(); - if (Info.Ctx.getAsConstantArrayType(MostRecentType)) - BaseType = MostRecentType; - } } else { const Expr *Base = LVal.Base.dyn_cast<const Expr*>(); @@ -4124,13 +4098,13 @@ static bool CheckConstexprFunction(EvalInfo &Info, SourceLocation CallLoc, if (Info.getLangOpts().CPlusPlus11) { const FunctionDecl *DiagDecl = Definition ? Definition : Declaration; - + // If this function is not constexpr because it is an inherited // non-constexpr constructor, diagnose that directly. auto *CD = dyn_cast<CXXConstructorDecl>(DiagDecl); if (CD && CD->isInheritingConstructor()) { auto *Inherited = CD->getInheritedConstructor().getConstructor(); - if (!Inherited->isConstexpr()) + if (!Inherited->isConstexpr()) DiagDecl = CD = Inherited; } @@ -4667,7 +4641,7 @@ public: return false; This = &ThisVal; Args = Args.slice(1); - } else if (MD && MD->isLambdaStaticInvoker()) { + } else if (MD && MD->isLambdaStaticInvoker()) { // Map the static invoker for the lambda back to the call operator. // Conveniently, we don't have to slice out the 'this' argument (as is // being done for the non-static case), since a static member function @@ -4702,7 +4676,7 @@ public: FD = LambdaCallOp; } - + } else return Error(E); @@ -5462,7 +5436,7 @@ static bool evaluateLValueAsAllocSize(EvalInfo &Info, APValue::LValueBase Base, Result.setInvalid(E); QualType Pointee = E->getType()->castAs<PointerType>()->getPointeeType(); - Result.addUnsizedArray(Info, E, Pointee); + Result.addUnsizedArray(Info, Pointee); return true; } @@ -5541,7 +5515,7 @@ public: // Update 'Result' to refer to the data member/field of the closure object // that represents the '*this' capture. if (!HandleLValueMember(Info, E, Result, - Info.CurrentCall->LambdaThisCaptureField)) + Info.CurrentCall->LambdaThisCaptureField)) return false; // If we captured '*this' by reference, replace the field with its referent. if (Info.CurrentCall->LambdaThisCaptureField->getType() @@ -5682,18 +5656,12 @@ bool PointerExprEvaluator::VisitCastExpr(const CastExpr* E) { Info, Result, SubExpr)) return false; } - // The result is a pointer to the first element of the array. if (const ConstantArrayType *CAT = Info.Ctx.getAsConstantArrayType(SubExpr->getType())) Result.addArray(Info, E, CAT); - // If the array hasn't been given a bound yet, add it as an unsized one. - else { - auto AT = Info.Ctx.getAsArrayType(SubExpr->getType()); - assert(AT && "Array to pointer decay on non-array object?"); - Result.addUnsizedArray(Info, E, AT->getElementType()); - } - + else + Result.Designator.setInvalid(); return true; case CK_FunctionToPointerDecay: @@ -5761,7 +5729,7 @@ bool PointerExprEvaluator::visitNonBuiltinCallExpr(const CallExpr *E) { Result.setInvalid(E); QualType PointeeTy = E->getType()->castAs<PointerType>()->getPointeeType(); - Result.addUnsizedArray(Info, E, PointeeTy); + Result.addUnsizedArray(Info, PointeeTy); return true; } @@ -6395,7 +6363,7 @@ bool RecordExprEvaluator::VisitLambdaExpr(const LambdaExpr *E) { if (ClosureClass->isInvalidDecl()) return false; if (Info.checkingPotentialConstantExpression()) return true; - + const size_t NumFields = std::distance(ClosureClass->field_begin(), ClosureClass->field_end()); @@ -6414,7 +6382,7 @@ bool RecordExprEvaluator::VisitLambdaExpr(const LambdaExpr *E) { assert(CaptureInitIt != E->capture_init_end()); // Get the initializer for this field Expr *const CurFieldInit = *CaptureInitIt++; - + // If there is no initializer, either this is a VLA or an error has // occurred. if (!CurFieldInit) @@ -6615,18 +6583,18 @@ VectorExprEvaluator::VisitInitListExpr(const InitListExpr *E) { // The number of initializers can be less than the number of // vector elements. For OpenCL, this can be due to nested vector - // initialization. For GCC compatibility, missing trailing elements + // initialization. For GCC compatibility, missing trailing elements // should be initialized with zeroes. unsigned CountInits = 0, CountElts = 0; while (CountElts < NumElements) { // Handle nested vector initialization. - if (CountInits < NumInits + if (CountInits < NumInits && E->getInit(CountInits)->getType()->isVectorType()) { APValue v; if (!EvaluateVector(E->getInit(CountInits), v, Info)) return Error(E); unsigned vlen = v.getVectorLength(); - for (unsigned j = 0; j < vlen; j++) + for (unsigned j = 0; j < vlen; j++) Elements.push_back(v.getVectorElt(j)); CountElts += vlen; } else if (EltTy->isIntegerType()) { @@ -6902,7 +6870,7 @@ public: } bool Success(const llvm::APInt &I, const Expr *E, APValue &Result) { - assert(E->getType()->isIntegralOrEnumerationType() && + assert(E->getType()->isIntegralOrEnumerationType() && "Invalid evaluation result."); assert(I.getBitWidth() == Info.Ctx.getIntWidth(E->getType()) && "Invalid evaluation result."); @@ -6916,7 +6884,7 @@ public: } bool Success(uint64_t Value, const Expr *E, APValue &Result) { - assert(E->getType()->isIntegralOrEnumerationType() && + assert(E->getType()->isIntegralOrEnumerationType() && "Invalid evaluation result."); Result = APValue(Info.Ctx.MakeIntValue(Value, E->getType())); return true; @@ -6992,7 +6960,7 @@ public: } return Success(Info.ArrayInitIndex, E); } - + // Note, GNU defines __null as an integer, not a pointer. bool VisitGNUNullExpr(const GNUNullExpr *E) { return ZeroInitialization(E); @@ -7356,8 +7324,10 @@ static bool isDesignatorAtObjectEnd(const ASTContext &Ctx, const LValue &LVal) { unsigned I = 0; QualType BaseType = getType(Base); - // If this is an alloc_size base, we should ignore the initial array index - if (isBaseAnAllocSizeCall(Base)) { + if (LVal.Designator.FirstEntryIsAnUnsizedArray) { + assert(isBaseAnAllocSizeCall(Base) && + "Unsized array in non-alloc_size call?"); + // If this is an alloc_size base, we should ignore the initial array index ++I; BaseType = BaseType->castAs<PointerType>()->getPointeeType(); } @@ -8144,12 +8114,12 @@ bool DataRecursiveIntBinOpEvaluator:: Result = RHSResult.Val; return true; } - + if (E->isLogicalOp()) { bool lhsResult, rhsResult; bool LHSIsOK = HandleConversionToBool(LHSResult.Val, lhsResult); bool RHSIsOK = HandleConversionToBool(RHSResult.Val, rhsResult); - + if (LHSIsOK) { if (RHSIsOK) { if (E->getOpcode() == BO_LOr) @@ -8165,26 +8135,26 @@ bool DataRecursiveIntBinOpEvaluator:: return Success(rhsResult, E, Result); } } - + return false; } - + assert(E->getLHS()->getType()->isIntegralOrEnumerationType() && E->getRHS()->getType()->isIntegralOrEnumerationType()); - + if (LHSResult.Failed || RHSResult.Failed) return false; - + const APValue &LHSVal = LHSResult.Val; const APValue &RHSVal = RHSResult.Val; - + // Handle cases like (unsigned long)&a + 4. if (E->isAdditiveOp() && LHSVal.isLValue() && RHSVal.isInt()) { Result = LHSVal; addOrSubLValueAsInteger(Result, RHSVal.getInt(), E->getOpcode() == BO_Sub); return true; } - + // Handle cases like 4 + (unsigned long)&a if (E->getOpcode() == BO_Add && RHSVal.isLValue() && LHSVal.isInt()) { @@ -8192,7 +8162,7 @@ bool DataRecursiveIntBinOpEvaluator:: addOrSubLValueAsInteger(Result, LHSVal.getInt(), /*IsSub*/false); return true; } - + if (E->getOpcode() == BO_Sub && LHSVal.isLValue() && RHSVal.isLValue()) { // Handle (intptr_t)&&A - (intptr_t)&&B. if (!LHSVal.getLValueOffset().isZero() || @@ -8231,7 +8201,7 @@ bool DataRecursiveIntBinOpEvaluator:: void DataRecursiveIntBinOpEvaluator::process(EvalResult &Result) { Job &job = Queue.back(); - + switch (job.Kind) { case Job::AnyExprKind: { if (const BinaryOperator *Bop = dyn_cast<BinaryOperator>(job.E)) { @@ -8241,12 +8211,12 @@ void DataRecursiveIntBinOpEvaluator::process(EvalResult &Result) { return; } } - + EvaluateExpr(job.E, Result); Queue.pop_back(); return; } - + case Job::BinOpKind: { const BinaryOperator *Bop = cast<BinaryOperator>(job.E); bool SuppressRHSDiags = false; @@ -8261,7 +8231,7 @@ void DataRecursiveIntBinOpEvaluator::process(EvalResult &Result) { enqueue(Bop->getRHS()); return; } - + case Job::BinOpVisitedLHSKind: { const BinaryOperator *Bop = cast<BinaryOperator>(job.E); EvalResult RHS; @@ -8271,7 +8241,7 @@ void DataRecursiveIntBinOpEvaluator::process(EvalResult &Result) { return; } } - + llvm_unreachable("Invalid Job::Kind!"); } @@ -8783,7 +8753,7 @@ bool IntExprEvaluator::VisitOffsetOfExpr(const OffsetOfExpr *OOE) { const RecordType *BaseRT = CurrentType->getAs<RecordType>(); if (!BaseRT) return Error(OOE); - + // Add the offset to the base. Result += RL.getBaseClassOffset(cast<CXXRecordDecl>(BaseRT->getDecl())); break; @@ -9978,7 +9948,7 @@ static bool FastEvaluateAsRValue(const Expr *Exp, Expr::EvalResult &Result, IsConst = false; return true; } - + // FIXME: Evaluating values of large array and record types can cause // performance problems. Only do so in C++11 for now. if (Exp->isRValue() && (Exp->getType()->isArrayType() || @@ -10000,7 +9970,7 @@ bool Expr::EvaluateAsRValue(EvalResult &Result, const ASTContext &Ctx) const { bool IsConst; if (FastEvaluateAsRValue(this, Result, Ctx, IsConst, false)) return IsConst; - + EvalInfo Info(Ctx, Result, EvalInfo::EM_IgnoreSideEffects); return ::EvaluateAsRValue(Info, this, Result.Val); } |