diff options
Diffstat (limited to 'lib/AST/ExprConstant.cpp')
| -rw-r--r-- | lib/AST/ExprConstant.cpp | 1167 |
1 files changed, 828 insertions, 339 deletions
diff --git a/lib/AST/ExprConstant.cpp b/lib/AST/ExprConstant.cpp index c1a42d8..dc61401 100644 --- a/lib/AST/ExprConstant.cpp +++ b/lib/AST/ExprConstant.cpp @@ -48,31 +48,110 @@ struct EvalInfo { /// EvalResult - Contains information about the evaluation. Expr::EvalResult &EvalResult; - /// AnyLValue - Stack based LValue results are not discarded. - bool AnyLValue; - - EvalInfo(ASTContext &ctx, Expr::EvalResult& evalresult, - bool anylvalue = false) - : Ctx(ctx), EvalResult(evalresult), AnyLValue(anylvalue) {} + EvalInfo(ASTContext &ctx, Expr::EvalResult& evalresult) + : Ctx(ctx), EvalResult(evalresult) {} }; +namespace { + struct ComplexValue { + private: + bool IsInt; -static bool EvaluateLValue(const Expr *E, APValue &Result, EvalInfo &Info); -static bool EvaluatePointer(const Expr *E, APValue &Result, EvalInfo &Info); + public: + APSInt IntReal, IntImag; + APFloat FloatReal, FloatImag; + + ComplexValue() : FloatReal(APFloat::Bogus), FloatImag(APFloat::Bogus) {} + + void makeComplexFloat() { IsInt = false; } + bool isComplexFloat() const { return !IsInt; } + APFloat &getComplexFloatReal() { return FloatReal; } + APFloat &getComplexFloatImag() { return FloatImag; } + + void makeComplexInt() { IsInt = true; } + bool isComplexInt() const { return IsInt; } + APSInt &getComplexIntReal() { return IntReal; } + APSInt &getComplexIntImag() { return IntImag; } + + void moveInto(APValue &v) { + if (isComplexFloat()) + v = APValue(FloatReal, FloatImag); + else + v = APValue(IntReal, IntImag); + } + }; + + struct LValue { + Expr *Base; + CharUnits Offset; + + Expr *getLValueBase() { return Base; } + CharUnits getLValueOffset() { return Offset; } + + void moveInto(APValue &v) { + v = APValue(Base, Offset); + } + }; +} + +static bool EvaluateLValue(const Expr *E, LValue &Result, EvalInfo &Info); +static bool EvaluatePointer(const Expr *E, LValue &Result, EvalInfo &Info); static bool EvaluateInteger(const Expr *E, APSInt &Result, EvalInfo &Info); static bool EvaluateIntegerOrLValue(const Expr *E, APValue &Result, EvalInfo &Info); static bool EvaluateFloat(const Expr *E, APFloat &Result, EvalInfo &Info); -static bool EvaluateComplex(const Expr *E, APValue &Result, EvalInfo &Info); +static bool EvaluateComplex(const Expr *E, ComplexValue &Res, EvalInfo &Info); //===----------------------------------------------------------------------===// // Misc utilities //===----------------------------------------------------------------------===// -static bool EvalPointerValueAsBool(APValue& Value, bool& Result) { - // FIXME: Is this accurate for all kinds of bases? If not, what would - // the check look like? - Result = Value.getLValueBase() || !Value.getLValueOffset().isZero(); +static bool IsGlobalLValue(const Expr* E) { + if (!E) return true; + + if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) { + if (isa<FunctionDecl>(DRE->getDecl())) + return true; + if (const VarDecl *VD = dyn_cast<VarDecl>(DRE->getDecl())) + return VD->hasGlobalStorage(); + return false; + } + + if (const CompoundLiteralExpr *CLE = dyn_cast<CompoundLiteralExpr>(E)) + return CLE->isFileScope(); + + return true; +} + +static bool EvalPointerValueAsBool(LValue& Value, bool& Result) { + const Expr* Base = Value.Base; + + // A null base expression indicates a null pointer. These are always + // evaluatable, and they are false unless the offset is zero. + if (!Base) { + Result = !Value.Offset.isZero(); + return true; + } + + // Require the base expression to be a global l-value. + if (!IsGlobalLValue(Base)) return false; + + // We have a non-null base expression. These are generally known to + // be true, but if it'a decl-ref to a weak symbol it can be null at + // runtime. + Result = true; + + const DeclRefExpr* DeclRef = dyn_cast<DeclRefExpr>(Base); + if (!DeclRef) + return true; + + // If it's a weak symbol, it isn't constant-evaluable. + const ValueDecl* Decl = DeclRef->getDecl(); + if (Decl->hasAttr<WeakAttr>() || + Decl->hasAttr<WeakRefAttr>() || + Decl->hasAttr<WeakImportAttr>()) + return false; + return true; } @@ -91,12 +170,12 @@ static bool HandleConversionToBool(const Expr* E, bool& Result, Result = !FloatResult.isZero(); return true; } else if (E->getType()->hasPointerRepresentation()) { - APValue PointerResult; + LValue PointerResult; if (!EvaluatePointer(E, PointerResult, Info)) return false; return EvalPointerValueAsBool(PointerResult, Result); } else if (E->getType()->isAnyComplexType()) { - APValue ComplexResult; + ComplexValue ComplexResult; if (!EvaluateComplex(E, ComplexResult, Info)) return false; if (ComplexResult.isComplexFloat()) { @@ -221,34 +300,42 @@ public: //===----------------------------------------------------------------------===// namespace { class LValueExprEvaluator - : public StmtVisitor<LValueExprEvaluator, APValue> { + : public StmtVisitor<LValueExprEvaluator, bool> { EvalInfo &Info; + LValue &Result; + + bool Success(Expr *E) { + Result.Base = E; + Result.Offset = CharUnits::Zero(); + return true; + } public: - LValueExprEvaluator(EvalInfo &info) : Info(info) {} + LValueExprEvaluator(EvalInfo &info, LValue &Result) : + Info(info), Result(Result) {} - APValue VisitStmt(Stmt *S) { - return APValue(); + bool VisitStmt(Stmt *S) { + return false; } - APValue VisitParenExpr(ParenExpr *E) { return Visit(E->getSubExpr()); } - APValue VisitDeclRefExpr(DeclRefExpr *E); - APValue VisitPredefinedExpr(PredefinedExpr *E) { return APValue(E); } - APValue VisitCompoundLiteralExpr(CompoundLiteralExpr *E); - APValue VisitMemberExpr(MemberExpr *E); - APValue VisitStringLiteral(StringLiteral *E) { return APValue(E); } - APValue VisitObjCEncodeExpr(ObjCEncodeExpr *E) { return APValue(E); } - APValue VisitArraySubscriptExpr(ArraySubscriptExpr *E); - APValue VisitUnaryDeref(UnaryOperator *E); - APValue VisitUnaryExtension(const UnaryOperator *E) + bool VisitParenExpr(ParenExpr *E) { return Visit(E->getSubExpr()); } + bool VisitDeclRefExpr(DeclRefExpr *E); + bool VisitPredefinedExpr(PredefinedExpr *E) { return Success(E); } + bool VisitCompoundLiteralExpr(CompoundLiteralExpr *E); + bool VisitMemberExpr(MemberExpr *E); + bool VisitStringLiteral(StringLiteral *E) { return Success(E); } + bool VisitObjCEncodeExpr(ObjCEncodeExpr *E) { return Success(E); } + bool VisitArraySubscriptExpr(ArraySubscriptExpr *E); + bool VisitUnaryDeref(UnaryOperator *E); + bool VisitUnaryExtension(const UnaryOperator *E) { return Visit(E->getSubExpr()); } - APValue VisitChooseExpr(const ChooseExpr *E) + bool VisitChooseExpr(const ChooseExpr *E) { return Visit(E->getChosenSubExpr(Info.Ctx)); } - APValue VisitCastExpr(CastExpr *E) { + bool VisitCastExpr(CastExpr *E) { switch (E->getCastKind()) { default: - return APValue(); + return false; case CastExpr::CK_NoOp: return Visit(E->getSubExpr()); @@ -258,44 +345,41 @@ public: }; } // end anonymous namespace -static bool EvaluateLValue(const Expr* E, APValue& Result, EvalInfo &Info) { - Result = LValueExprEvaluator(Info).Visit(const_cast<Expr*>(E)); - return Result.isLValue(); +static bool EvaluateLValue(const Expr* E, LValue& Result, EvalInfo &Info) { + return LValueExprEvaluator(Info, Result).Visit(const_cast<Expr*>(E)); } -APValue LValueExprEvaluator::VisitDeclRefExpr(DeclRefExpr *E) { +bool LValueExprEvaluator::VisitDeclRefExpr(DeclRefExpr *E) { if (isa<FunctionDecl>(E->getDecl())) { - return APValue(E); + return Success(E); } else if (VarDecl* VD = dyn_cast<VarDecl>(E->getDecl())) { - if (!Info.AnyLValue && !VD->hasGlobalStorage()) - return APValue(); if (!VD->getType()->isReferenceType()) - return APValue(E); + return Success(E); + // Reference parameters can refer to anything even if they have an + // "initializer" in the form of a default argument. + if (isa<ParmVarDecl>(VD)) + return false; // FIXME: Check whether VD might be overridden! if (const Expr *Init = VD->getAnyInitializer()) return Visit(const_cast<Expr *>(Init)); } - return APValue(); + return false; } -APValue LValueExprEvaluator::VisitCompoundLiteralExpr(CompoundLiteralExpr *E) { - if (!Info.AnyLValue && !E->isFileScope()) - return APValue(); - return APValue(E); +bool LValueExprEvaluator::VisitCompoundLiteralExpr(CompoundLiteralExpr *E) { + return Success(E); } -APValue LValueExprEvaluator::VisitMemberExpr(MemberExpr *E) { - APValue result; +bool LValueExprEvaluator::VisitMemberExpr(MemberExpr *E) { QualType Ty; if (E->isArrow()) { - if (!EvaluatePointer(E->getBase(), result, Info)) - return APValue(); + if (!EvaluatePointer(E->getBase(), Result, Info)) + return false; Ty = E->getBase()->getType()->getAs<PointerType>()->getPointeeType(); } else { - result = Visit(E->getBase()); - if (result.isUninit()) - return APValue(); + if (!Visit(E->getBase())) + return false; Ty = E->getBase()->getType(); } @@ -304,10 +388,10 @@ APValue LValueExprEvaluator::VisitMemberExpr(MemberExpr *E) { FieldDecl *FD = dyn_cast<FieldDecl>(E->getMemberDecl()); if (!FD) // FIXME: deal with other kinds of member expressions - return APValue(); + return false; if (FD->getType()->isReferenceType()) - return APValue(); + return false; // FIXME: This is linear time. unsigned i = 0; @@ -318,36 +402,25 @@ APValue LValueExprEvaluator::VisitMemberExpr(MemberExpr *E) { break; } - result.setLValue(result.getLValueBase(), - result.getLValueOffset() + - CharUnits::fromQuantity(RL.getFieldOffset(i) / 8)); - - return result; + Result.Offset += CharUnits::fromQuantity(RL.getFieldOffset(i) / 8); + return true; } -APValue LValueExprEvaluator::VisitArraySubscriptExpr(ArraySubscriptExpr *E) { - APValue Result; - +bool LValueExprEvaluator::VisitArraySubscriptExpr(ArraySubscriptExpr *E) { if (!EvaluatePointer(E->getBase(), Result, Info)) - return APValue(); + return false; APSInt Index; if (!EvaluateInteger(E->getIdx(), Index, Info)) - return APValue(); + return false; CharUnits ElementSize = Info.Ctx.getTypeSizeInChars(E->getType()); - - CharUnits Offset = Index.getSExtValue() * ElementSize; - Result.setLValue(Result.getLValueBase(), - Result.getLValueOffset() + Offset); - return Result; + Result.Offset += Index.getSExtValue() * ElementSize; + return true; } -APValue LValueExprEvaluator::VisitUnaryDeref(UnaryOperator *E) { - APValue Result; - if (!EvaluatePointer(E->getSubExpr(), Result, Info)) - return APValue(); - return Result; +bool LValueExprEvaluator::VisitUnaryDeref(UnaryOperator *E) { + return EvaluatePointer(E->getSubExpr(), Result, Info); } //===----------------------------------------------------------------------===// @@ -356,104 +429,103 @@ APValue LValueExprEvaluator::VisitUnaryDeref(UnaryOperator *E) { namespace { class PointerExprEvaluator - : public StmtVisitor<PointerExprEvaluator, APValue> { + : public StmtVisitor<PointerExprEvaluator, bool> { EvalInfo &Info; + LValue &Result; + + bool Success(Expr *E) { + Result.Base = E; + Result.Offset = CharUnits::Zero(); + return true; + } public: - PointerExprEvaluator(EvalInfo &info) : Info(info) {} + PointerExprEvaluator(EvalInfo &info, LValue &Result) + : Info(info), Result(Result) {} - APValue VisitStmt(Stmt *S) { - return APValue(); + bool VisitStmt(Stmt *S) { + return false; } - APValue VisitParenExpr(ParenExpr *E) { return Visit(E->getSubExpr()); } + bool VisitParenExpr(ParenExpr *E) { return Visit(E->getSubExpr()); } - APValue VisitBinaryOperator(const BinaryOperator *E); - APValue VisitCastExpr(CastExpr* E); - APValue VisitUnaryExtension(const UnaryOperator *E) + bool VisitBinaryOperator(const BinaryOperator *E); + bool VisitCastExpr(CastExpr* E); + bool VisitUnaryExtension(const UnaryOperator *E) { return Visit(E->getSubExpr()); } - APValue VisitUnaryAddrOf(const UnaryOperator *E); - APValue VisitObjCStringLiteral(ObjCStringLiteral *E) - { return APValue(E); } - APValue VisitAddrLabelExpr(AddrLabelExpr *E) - { return APValue(E); } - APValue VisitCallExpr(CallExpr *E); - APValue VisitBlockExpr(BlockExpr *E) { + bool VisitUnaryAddrOf(const UnaryOperator *E); + bool VisitObjCStringLiteral(ObjCStringLiteral *E) + { return Success(E); } + bool VisitAddrLabelExpr(AddrLabelExpr *E) + { return Success(E); } + bool VisitCallExpr(CallExpr *E); + bool VisitBlockExpr(BlockExpr *E) { if (!E->hasBlockDeclRefExprs()) - return APValue(E); - return APValue(); + return Success(E); + return false; } - APValue VisitImplicitValueInitExpr(ImplicitValueInitExpr *E) - { return APValue((Expr*)0); } - APValue VisitConditionalOperator(ConditionalOperator *E); - APValue VisitChooseExpr(ChooseExpr *E) + bool VisitImplicitValueInitExpr(ImplicitValueInitExpr *E) + { return Success((Expr*)0); } + bool VisitConditionalOperator(ConditionalOperator *E); + bool VisitChooseExpr(ChooseExpr *E) { return Visit(E->getChosenSubExpr(Info.Ctx)); } - APValue VisitCXXNullPtrLiteralExpr(CXXNullPtrLiteralExpr *E) - { return APValue((Expr*)0); } + bool VisitCXXNullPtrLiteralExpr(CXXNullPtrLiteralExpr *E) + { return Success((Expr*)0); } // FIXME: Missing: @protocol, @selector }; } // end anonymous namespace -static bool EvaluatePointer(const Expr* E, APValue& Result, EvalInfo &Info) { - if (!E->getType()->hasPointerRepresentation()) - return false; - Result = PointerExprEvaluator(Info).Visit(const_cast<Expr*>(E)); - return Result.isLValue(); +static bool EvaluatePointer(const Expr* E, LValue& Result, EvalInfo &Info) { + assert(E->getType()->hasPointerRepresentation()); + return PointerExprEvaluator(Info, Result).Visit(const_cast<Expr*>(E)); } -APValue PointerExprEvaluator::VisitBinaryOperator(const BinaryOperator *E) { +bool PointerExprEvaluator::VisitBinaryOperator(const BinaryOperator *E) { if (E->getOpcode() != BinaryOperator::Add && E->getOpcode() != BinaryOperator::Sub) - return APValue(); + return false; const Expr *PExp = E->getLHS(); const Expr *IExp = E->getRHS(); if (IExp->getType()->isPointerType()) std::swap(PExp, IExp); - APValue ResultLValue; - if (!EvaluatePointer(PExp, ResultLValue, Info)) - return APValue(); + if (!EvaluatePointer(PExp, Result, Info)) + return false; - llvm::APSInt AdditionalOffset; - if (!EvaluateInteger(IExp, AdditionalOffset, Info)) - return APValue(); + llvm::APSInt Offset; + if (!EvaluateInteger(IExp, Offset, Info)) + return false; + int64_t AdditionalOffset + = Offset.isSigned() ? Offset.getSExtValue() + : static_cast<int64_t>(Offset.getZExtValue()); // Compute the new offset in the appropriate width. QualType PointeeType = PExp->getType()->getAs<PointerType>()->getPointeeType(); - llvm::APSInt SizeOfPointee(AdditionalOffset); + CharUnits SizeOfPointee; // Explicitly handle GNU void* and function pointer arithmetic extensions. if (PointeeType->isVoidType() || PointeeType->isFunctionType()) - SizeOfPointee = 1; + SizeOfPointee = CharUnits::One(); else - SizeOfPointee = Info.Ctx.getTypeSizeInChars(PointeeType).getQuantity(); + SizeOfPointee = Info.Ctx.getTypeSizeInChars(PointeeType); - llvm::APSInt Offset(AdditionalOffset); - Offset = ResultLValue.getLValueOffset().getQuantity(); if (E->getOpcode() == BinaryOperator::Add) - Offset += AdditionalOffset * SizeOfPointee; + Result.Offset += AdditionalOffset * SizeOfPointee; else - Offset -= AdditionalOffset * SizeOfPointee; + Result.Offset -= AdditionalOffset * SizeOfPointee; - // Sign extend prior to converting back to a char unit. - if (Offset.getBitWidth() < 64) - Offset.extend(64); - return APValue(ResultLValue.getLValueBase(), - CharUnits::fromQuantity(Offset.getLimitedValue())); + return true; } -APValue PointerExprEvaluator::VisitUnaryAddrOf(const UnaryOperator *E) { - APValue result; - if (EvaluateLValue(E->getSubExpr(), result, Info)) - return result; - return APValue(); +bool PointerExprEvaluator::VisitUnaryAddrOf(const UnaryOperator *E) { + return EvaluateLValue(E->getSubExpr(), Result, Info); } -APValue PointerExprEvaluator::VisitCastExpr(CastExpr* E) { +bool PointerExprEvaluator::VisitCastExpr(CastExpr* E) { Expr* SubExpr = E->getSubExpr(); switch (E->getCastKind()) { @@ -471,18 +543,20 @@ APValue PointerExprEvaluator::VisitCastExpr(CastExpr* E) { return Visit(SubExpr); if (SubExpr->getType()->isIntegralType()) { - APValue Result; - if (!EvaluateIntegerOrLValue(SubExpr, Result, Info)) + APValue Value; + if (!EvaluateIntegerOrLValue(SubExpr, Value, Info)) break; - if (Result.isInt()) { - Result.getInt().extOrTrunc((unsigned)Info.Ctx.getTypeSize(E->getType())); - return APValue(0, - CharUnits::fromQuantity(Result.getInt().getZExtValue())); + if (Value.isInt()) { + Value.getInt().extOrTrunc((unsigned)Info.Ctx.getTypeSize(E->getType())); + Result.Base = 0; + Result.Offset = CharUnits::fromQuantity(Value.getInt().getZExtValue()); + return true; + } else { + Result.Base = Value.getLValueBase(); + Result.Offset = Value.getLValueOffset(); + return true; } - - // Cast is of an lvalue, no need to change value. - return Result; } break; } @@ -494,51 +568,46 @@ APValue PointerExprEvaluator::VisitCastExpr(CastExpr* E) { return Visit(SubExpr); case CastExpr::CK_IntegralToPointer: { - APValue Result; - if (!EvaluateIntegerOrLValue(SubExpr, Result, Info)) + APValue Value; + if (!EvaluateIntegerOrLValue(SubExpr, Value, Info)) break; - if (Result.isInt()) { - Result.getInt().extOrTrunc((unsigned)Info.Ctx.getTypeSize(E->getType())); - return APValue(0, - CharUnits::fromQuantity(Result.getInt().getZExtValue())); + if (Value.isInt()) { + Value.getInt().extOrTrunc((unsigned)Info.Ctx.getTypeSize(E->getType())); + Result.Base = 0; + Result.Offset = CharUnits::fromQuantity(Value.getInt().getZExtValue()); + return true; + } else { + // Cast is of an lvalue, no need to change value. + Result.Base = Value.getLValueBase(); + Result.Offset = Value.getLValueOffset(); + return true; } - - // Cast is of an lvalue, no need to change value. - return Result; } case CastExpr::CK_ArrayToPointerDecay: - case CastExpr::CK_FunctionToPointerDecay: { - APValue Result; - if (EvaluateLValue(SubExpr, Result, Info)) - return Result; - break; - } + case CastExpr::CK_FunctionToPointerDecay: + return EvaluateLValue(SubExpr, Result, Info); } - return APValue(); + return false; } -APValue PointerExprEvaluator::VisitCallExpr(CallExpr *E) { +bool PointerExprEvaluator::VisitCallExpr(CallExpr *E) { if (E->isBuiltinCall(Info.Ctx) == Builtin::BI__builtin___CFStringMakeConstantString || E->isBuiltinCall(Info.Ctx) == Builtin::BI__builtin___NSStringMakeConstantString) - return APValue(E); - return APValue(); + return Success(E); + return false; } -APValue PointerExprEvaluator::VisitConditionalOperator(ConditionalOperator *E) { +bool PointerExprEvaluator::VisitConditionalOperator(ConditionalOperator *E) { bool BoolResult; if (!HandleConversionToBool(E->getCond(), BoolResult, Info)) - return APValue(); + return false; Expr* EvalExpr = BoolResult ? E->getTrueExpr() : E->getFalseExpr(); - - APValue Result; - if (EvaluatePointer(EvalExpr, Result, Info)) - return Result; - return APValue(); + return Visit(EvalExpr); } //===----------------------------------------------------------------------===// @@ -867,18 +936,20 @@ public: private: CharUnits GetAlignOfExpr(const Expr *E); CharUnits GetAlignOfType(QualType T); + static QualType GetObjectType(const Expr *E); + bool TryEvaluateBuiltinObjectSize(CallExpr *E); // FIXME: Missing: array subscript of vector, member of vector }; } // end anonymous namespace static bool EvaluateIntegerOrLValue(const Expr* E, APValue &Result, EvalInfo &Info) { - if (!E->getType()->isIntegralType()) - return false; - + assert(E->getType()->isIntegralType()); return IntExprEvaluator(Info, Result).Visit(const_cast<Expr*>(E)); } static bool EvaluateInteger(const Expr* E, APSInt &Result, EvalInfo &Info) { + assert(E->getType()->isIntegralType()); + APValue Val; if (!EvaluateIntegerOrLValue(E, Val, Info) || !Val.isInt()) return false; @@ -984,36 +1055,55 @@ static int EvaluateBuiltinClassifyType(const CallExpr *E) { return -1; } +/// Retrieves the "underlying object type" of the given expression, +/// as used by __builtin_object_size. +QualType IntExprEvaluator::GetObjectType(const Expr *E) { + if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) { + if (const VarDecl *VD = dyn_cast<VarDecl>(DRE->getDecl())) + return VD->getType(); + } else if (isa<CompoundLiteralExpr>(E)) { + return E->getType(); + } + + return QualType(); +} + +bool IntExprEvaluator::TryEvaluateBuiltinObjectSize(CallExpr *E) { + // TODO: Perhaps we should let LLVM lower this? + LValue Base; + if (!EvaluatePointer(E->getArg(0), Base, Info)) + return false; + + // If we can prove the base is null, lower to zero now. + const Expr *LVBase = Base.getLValueBase(); + if (!LVBase) return Success(0, E); + + QualType T = GetObjectType(LVBase); + if (T.isNull() || + T->isIncompleteType() || + !T->isObjectType() || + T->isVariablyModifiedType() || + T->isDependentType()) + return false; + + CharUnits Size = Info.Ctx.getTypeSizeInChars(T); + CharUnits Offset = Base.getLValueOffset(); + + if (!Offset.isNegative() && Offset <= Size) + Size -= Offset; + else + Size = CharUnits::Zero(); + return Success(Size.getQuantity(), E); +} + bool IntExprEvaluator::VisitCallExpr(CallExpr *E) { switch (E->isBuiltinCall(Info.Ctx)) { default: return Error(E->getLocStart(), diag::note_invalid_subexpr_in_ice, E); case Builtin::BI__builtin_object_size: { - const Expr *Arg = E->getArg(0)->IgnoreParens(); - Expr::EvalResult Base; - - // TODO: Perhaps we should let LLVM lower this? - if (Arg->EvaluateAsAny(Base, Info.Ctx) - && Base.Val.getKind() == APValue::LValue - && !Base.HasSideEffects) - if (const Expr *LVBase = Base.Val.getLValueBase()) - if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(LVBase)) { - if (const VarDecl *VD = dyn_cast<VarDecl>(DRE->getDecl())) { - if (!VD->getType()->isIncompleteType() - && VD->getType()->isObjectType() - && !VD->getType()->isVariablyModifiedType() - && !VD->getType()->isDependentType()) { - CharUnits Size = Info.Ctx.getTypeSizeInChars(VD->getType()); - CharUnits Offset = Base.Val.getLValueOffset(); - if (!Offset.isNegative() && Offset <= Size) - Size -= Offset; - else - Size = CharUnits::Zero(); - return Success(Size.getQuantity(), E); - } - } - } + if (TryEvaluateBuiltinObjectSize(E)) + return true; // If evaluating the argument has side-effects we can't determine // the size of the object and lower it to unknown now. @@ -1098,7 +1188,7 @@ bool IntExprEvaluator::VisitBinaryOperator(const BinaryOperator *E) { if (LHSTy->isAnyComplexType()) { assert(RHSTy->isAnyComplexType() && "Invalid comparison"); - APValue LHS, RHS; + ComplexValue LHS, RHS; if (!EvaluateComplex(E->getLHS(), LHS, Info)) return false; @@ -1173,11 +1263,11 @@ bool IntExprEvaluator::VisitBinaryOperator(const BinaryOperator *E) { if (LHSTy->isPointerType() && RHSTy->isPointerType()) { if (E->getOpcode() == BinaryOperator::Sub || E->isEqualityOp()) { - APValue LHSValue; + LValue LHSValue; if (!EvaluatePointer(E->getLHS(), LHSValue, Info)) return false; - APValue RHSValue; + LValue RHSValue; if (!EvaluatePointer(E->getRHS(), RHSValue, Info)) return false; @@ -1463,7 +1553,7 @@ bool IntExprEvaluator::VisitUnaryOperator(const UnaryOperator *E) { if (E->isOffsetOfOp()) { // The AST for offsetof is defined in such a way that we can just // directly Evaluate it as an l-value. - APValue LV; + LValue LV; if (!EvaluateLValue(E->getSubExpr(), LV, Info)) return false; if (LV.getLValueBase()) @@ -1538,7 +1628,7 @@ bool IntExprEvaluator::VisitCastExpr(CastExpr *E) { // FIXME: Clean this up! if (SrcType->isPointerType()) { - APValue LV; + LValue LV; if (!EvaluatePointer(SubExpr, LV, Info)) return false; @@ -1547,7 +1637,7 @@ bool IntExprEvaluator::VisitCastExpr(CastExpr *E) { if (Info.Ctx.getTypeSize(DestType) != Info.Ctx.getTypeSize(SrcType)) return false; - Result = LV; + LV.moveInto(Result); return true; } @@ -1559,19 +1649,19 @@ bool IntExprEvaluator::VisitCastExpr(CastExpr *E) { if (SrcType->isArrayType() || SrcType->isFunctionType()) { // This handles double-conversion cases, where there's both // an l-value promotion and an implicit conversion to int. - APValue LV; + LValue LV; if (!EvaluateLValue(SubExpr, LV, Info)) return false; if (Info.Ctx.getTypeSize(DestType) != Info.Ctx.getTypeSize(Info.Ctx.VoidPtrTy)) return false; - Result = LV; + LV.moveInto(Result); return true; } if (SrcType->isAnyComplexType()) { - APValue C; + ComplexValue C; if (!EvaluateComplex(SubExpr, C, Info)) return false; if (C.isComplexFloat()) @@ -1596,7 +1686,7 @@ bool IntExprEvaluator::VisitCastExpr(CastExpr *E) { bool IntExprEvaluator::VisitUnaryReal(const UnaryOperator *E) { if (E->getSubExpr()->getType()->isAnyComplexType()) { - APValue LV; + ComplexValue LV; if (!EvaluateComplex(E->getSubExpr(), LV, Info) || !LV.isComplexInt()) return Error(E->getExprLoc(), diag::note_invalid_subexpr_in_ice, E); return Success(LV.getComplexIntReal(), E); @@ -1607,7 +1697,7 @@ bool IntExprEvaluator::VisitUnaryReal(const UnaryOperator *E) { bool IntExprEvaluator::VisitUnaryImag(const UnaryOperator *E) { if (E->getSubExpr()->getType()->isComplexIntegerType()) { - APValue LV; + ComplexValue LV; if (!EvaluateComplex(E->getSubExpr(), LV, Info) || !LV.isComplexInt()) return Error(E->getExprLoc(), diag::note_invalid_subexpr_in_ice, E); return Success(LV.getComplexIntImag(), E); @@ -1649,13 +1739,16 @@ public: { return Visit(E->getChosenSubExpr(Info.Ctx)); } bool VisitUnaryExtension(const UnaryOperator *E) { return Visit(E->getSubExpr()); } + bool VisitUnaryReal(const UnaryOperator *E); + bool VisitUnaryImag(const UnaryOperator *E); - // FIXME: Missing: __real__/__imag__, array subscript of vector, - // member of vector, ImplicitValueInitExpr + // FIXME: Missing: array subscript of vector, member of vector, + // ImplicitValueInitExpr }; } // end anonymous namespace static bool EvaluateFloat(const Expr* E, APFloat& Result, EvalInfo &Info) { + assert(E->getType()->isRealFloatingType()); return FloatExprEvaluator(Info, Result).Visit(const_cast<Expr*>(E)); } @@ -1736,6 +1829,22 @@ bool FloatExprEvaluator::VisitCallExpr(const CallExpr *E) { } } +bool FloatExprEvaluator::VisitUnaryReal(const UnaryOperator *E) { + ComplexValue CV; + if (!EvaluateComplex(E->getSubExpr(), CV, Info)) + return false; + Result = CV.FloatReal; + return true; +} + +bool FloatExprEvaluator::VisitUnaryImag(const UnaryOperator *E) { + ComplexValue CV; + if (!EvaluateComplex(E->getSubExpr(), CV, Info)) + return false; + Result = CV.FloatImag; + return true; +} + bool FloatExprEvaluator::VisitUnaryOperator(const UnaryOperator *E) { if (E->getOpcode() == UnaryOperator::Deref) return false; @@ -1838,166 +1947,170 @@ bool FloatExprEvaluator::VisitConditionalOperator(ConditionalOperator *E) { namespace { class ComplexExprEvaluator - : public StmtVisitor<ComplexExprEvaluator, APValue> { + : public StmtVisitor<ComplexExprEvaluator, bool> { EvalInfo &Info; + ComplexValue &Result; public: - ComplexExprEvaluator(EvalInfo &info) : Info(info) {} + ComplexExprEvaluator(EvalInfo &info, ComplexValue &Result) + : Info(info), Result(Result) {} //===--------------------------------------------------------------------===// // Visitor Methods //===--------------------------------------------------------------------===// - APValue VisitStmt(Stmt *S) { - return APValue(); + bool VisitStmt(Stmt *S) { + return false; } - APValue VisitParenExpr(ParenExpr *E) { return Visit(E->getSubExpr()); } + bool VisitParenExpr(ParenExpr *E) { return Visit(E->getSubExpr()); } - APValue VisitImaginaryLiteral(ImaginaryLiteral *E) { + bool VisitImaginaryLiteral(ImaginaryLiteral *E) { Expr* SubExpr = E->getSubExpr(); if (SubExpr->getType()->isRealFloatingType()) { - APFloat Result(0.0); - - if (!EvaluateFloat(SubExpr, Result, Info)) - return APValue(); + Result.makeComplexFloat(); + APFloat &Imag = Result.FloatImag; + if (!EvaluateFloat(SubExpr, Imag, Info)) + return false; - return APValue(APFloat(Result.getSemantics(), APFloat::fcZero, false), - Result); + Result.FloatReal = APFloat(Imag.getSemantics()); + return true; } else { assert(SubExpr->getType()->isIntegerType() && "Unexpected imaginary literal."); - llvm::APSInt Result; - if (!EvaluateInteger(SubExpr, Result, Info)) - return APValue(); + Result.makeComplexInt(); + APSInt &Imag = Result.IntImag; + if (!EvaluateInteger(SubExpr, Imag, Info)) + return false; - llvm::APSInt Zero(Result.getBitWidth(), !Result.isSigned()); - Zero = 0; - return APValue(Zero, Result); + Result.IntReal = APSInt(Imag.getBitWidth(), !Imag.isSigned()); + return true; } } - APValue VisitCastExpr(CastExpr *E) { + bool VisitCastExpr(CastExpr *E) { Expr* SubExpr = E->getSubExpr(); QualType EltType = E->getType()->getAs<ComplexType>()->getElementType(); QualType SubType = SubExpr->getType(); if (SubType->isRealFloatingType()) { - APFloat Result(0.0); - - if (!EvaluateFloat(SubExpr, Result, Info)) - return APValue(); + APFloat &Real = Result.FloatReal; + if (!EvaluateFloat(SubExpr, Real, Info)) + return false; if (EltType->isRealFloatingType()) { - Result = HandleFloatToFloatCast(EltType, SubType, Result, Info.Ctx); - return APValue(Result, - APFloat(Result.getSemantics(), APFloat::fcZero, false)); + Result.makeComplexFloat(); + Real = HandleFloatToFloatCast(EltType, SubType, Real, Info.Ctx); + Result.FloatImag = APFloat(Real.getSemantics()); + return true; } else { - llvm::APSInt IResult; - IResult = HandleFloatToIntCast(EltType, SubType, Result, Info.Ctx); - llvm::APSInt Zero(IResult.getBitWidth(), !IResult.isSigned()); - Zero = 0; - return APValue(IResult, Zero); + Result.makeComplexInt(); + Result.IntReal = HandleFloatToIntCast(EltType, SubType, Real, Info.Ctx); + Result.IntImag = APSInt(Result.IntReal.getBitWidth(), + !Result.IntReal.isSigned()); + return true; } } else if (SubType->isIntegerType()) { - APSInt Result; - - if (!EvaluateInteger(SubExpr, Result, Info)) - return APValue(); + APSInt &Real = Result.IntReal; + if (!EvaluateInteger(SubExpr, Real, Info)) + return false; if (EltType->isRealFloatingType()) { - APFloat FResult = - HandleIntToFloatCast(EltType, SubType, Result, Info.Ctx); - return APValue(FResult, - APFloat(FResult.getSemantics(), APFloat::fcZero, false)); + Result.makeComplexFloat(); + Result.FloatReal + = HandleIntToFloatCast(EltType, SubType, Real, Info.Ctx); + Result.FloatImag = APFloat(Result.FloatReal.getSemantics()); + return true; } else { - Result = HandleIntToIntCast(EltType, SubType, Result, Info.Ctx); - llvm::APSInt Zero(Result.getBitWidth(), !Result.isSigned()); - Zero = 0; - return APValue(Result, Zero); + Result.makeComplexInt(); + Real = HandleIntToIntCast(EltType, SubType, Real, Info.Ctx); + Result.IntImag = APSInt(Real.getBitWidth(), !Real.isSigned()); + return true; } } else if (const ComplexType *CT = SubType->getAs<ComplexType>()) { - APValue Src; - - if (!EvaluateComplex(SubExpr, Src, Info)) - return APValue(); + if (!Visit(SubExpr)) + return false; QualType SrcType = CT->getElementType(); - if (Src.isComplexFloat()) { + if (Result.isComplexFloat()) { if (EltType->isRealFloatingType()) { - return APValue(HandleFloatToFloatCast(EltType, SrcType, - Src.getComplexFloatReal(), - Info.Ctx), - HandleFloatToFloatCast(EltType, SrcType, - Src.getComplexFloatImag(), - Info.Ctx)); + Result.makeComplexFloat(); + Result.FloatReal = HandleFloatToFloatCast(EltType, SrcType, + Result.FloatReal, + Info.Ctx); + Result.FloatImag = HandleFloatToFloatCast(EltType, SrcType, + Result.FloatImag, + Info.Ctx); + return true; } else { - return APValue(HandleFloatToIntCast(EltType, SrcType, - Src.getComplexFloatReal(), - Info.Ctx), - HandleFloatToIntCast(EltType, SrcType, - Src.getComplexFloatImag(), - Info.Ctx)); + Result.makeComplexInt(); + Result.IntReal = HandleFloatToIntCast(EltType, SrcType, + Result.FloatReal, + Info.Ctx); + Result.IntImag = HandleFloatToIntCast(EltType, SrcType, + Result.FloatImag, + Info.Ctx); + return true; } } else { - assert(Src.isComplexInt() && "Invalid evaluate result."); + assert(Result.isComplexInt() && "Invalid evaluate result."); if (EltType->isRealFloatingType()) { - return APValue(HandleIntToFloatCast(EltType, SrcType, - Src.getComplexIntReal(), - Info.Ctx), - HandleIntToFloatCast(EltType, SrcType, - Src.getComplexIntImag(), - Info.Ctx)); + Result.makeComplexFloat(); + Result.FloatReal = HandleIntToFloatCast(EltType, SrcType, + Result.IntReal, + Info.Ctx); + Result.FloatImag = HandleIntToFloatCast(EltType, SrcType, + Result.IntImag, + Info.Ctx); + return true; } else { - return APValue(HandleIntToIntCast(EltType, SrcType, - Src.getComplexIntReal(), - Info.Ctx), - HandleIntToIntCast(EltType, SrcType, - Src.getComplexIntImag(), - Info.Ctx)); + Result.makeComplexInt(); + Result.IntReal = HandleIntToIntCast(EltType, SrcType, + Result.IntReal, + Info.Ctx); + Result.IntImag = HandleIntToIntCast(EltType, SrcType, + Result.IntImag, + Info.Ctx); + return true; } } } // FIXME: Handle more casts. - return APValue(); + return false; } - APValue VisitBinaryOperator(const BinaryOperator *E); - APValue VisitChooseExpr(const ChooseExpr *E) + bool VisitBinaryOperator(const BinaryOperator *E); + bool VisitChooseExpr(const ChooseExpr *E) { return Visit(E->getChosenSubExpr(Info.Ctx)); } - APValue VisitUnaryExtension(const UnaryOperator *E) + bool VisitUnaryExtension(const UnaryOperator *E) { return Visit(E->getSubExpr()); } // FIXME Missing: unary +/-/~, binary div, ImplicitValueInitExpr, // conditional ?:, comma }; } // end anonymous namespace -static bool EvaluateComplex(const Expr *E, APValue &Result, EvalInfo &Info) { - Result = ComplexExprEvaluator(Info).Visit(const_cast<Expr*>(E)); - assert((!Result.isComplexFloat() || - (&Result.getComplexFloatReal().getSemantics() == - &Result.getComplexFloatImag().getSemantics())) && - "Invalid complex evaluation."); - return Result.isComplexFloat() || Result.isComplexInt(); +static bool EvaluateComplex(const Expr *E, ComplexValue &Result, + EvalInfo &Info) { + assert(E->getType()->isAnyComplexType()); + return ComplexExprEvaluator(Info, Result).Visit(const_cast<Expr*>(E)); } -APValue ComplexExprEvaluator::VisitBinaryOperator(const BinaryOperator *E) { - APValue Result, RHS; - - if (!EvaluateComplex(E->getLHS(), Result, Info)) - return APValue(); +bool ComplexExprEvaluator::VisitBinaryOperator(const BinaryOperator *E) { + if (!Visit(E->getLHS())) + return false; + ComplexValue RHS; if (!EvaluateComplex(E->getRHS(), RHS, Info)) - return APValue(); + return false; assert(Result.isComplexFloat() == RHS.isComplexFloat() && "Invalid operands to binary operator."); switch (E->getOpcode()) { - default: return APValue(); + default: return false; case BinaryOperator::Add: if (Result.isComplexFloat()) { Result.getComplexFloatReal().add(RHS.getComplexFloatReal(), @@ -2022,7 +2135,7 @@ APValue ComplexExprEvaluator::VisitBinaryOperator(const BinaryOperator *E) { break; case BinaryOperator::Mul: if (Result.isComplexFloat()) { - APValue LHS = Result; + ComplexValue LHS = Result; APFloat &LHS_r = LHS.getComplexFloatReal(); APFloat &LHS_i = LHS.getComplexFloatImag(); APFloat &RHS_r = RHS.getComplexFloatReal(); @@ -2042,7 +2155,7 @@ APValue ComplexExprEvaluator::VisitBinaryOperator(const BinaryOperator *E) { Tmp.multiply(RHS_r, APFloat::rmNearestTiesToEven); Result.getComplexFloatImag().add(Tmp, APFloat::rmNearestTiesToEven); } else { - APValue LHS = Result; + ComplexValue LHS = Result; Result.getComplexIntReal() = (LHS.getComplexIntReal() * RHS.getComplexIntReal() - LHS.getComplexIntImag() * RHS.getComplexIntImag()); @@ -2053,7 +2166,7 @@ APValue ComplexExprEvaluator::VisitBinaryOperator(const BinaryOperator *E) { break; } - return Result; + return true; } //===----------------------------------------------------------------------===// @@ -2065,53 +2178,32 @@ APValue ComplexExprEvaluator::VisitBinaryOperator(const BinaryOperator *E) { /// we want to. If this function returns true, it returns the folded constant /// in Result. bool Expr::Evaluate(EvalResult &Result, ASTContext &Ctx) const { + const Expr *E = this; EvalInfo Info(Ctx, Result); - - if (getType()->isVectorType()) { - if (!EvaluateVector(this, Result.Val, Info)) + if (E->getType()->isVectorType()) { + if (!EvaluateVector(E, Info.EvalResult.Val, Info)) return false; - } else if (getType()->isIntegerType()) { - if (!IntExprEvaluator(Info, Result.Val).Visit(const_cast<Expr*>(this))) + } else if (E->getType()->isIntegerType()) { + if (!IntExprEvaluator(Info, Info.EvalResult.Val).Visit(const_cast<Expr*>(E))) return false; - } else if (getType()->hasPointerRepresentation()) { - if (!EvaluatePointer(this, Result.Val, Info)) - return false; - } else if (getType()->isRealFloatingType()) { - llvm::APFloat f(0.0); - if (!EvaluateFloat(this, f, Info)) - return false; - - Result.Val = APValue(f); - } else if (getType()->isAnyComplexType()) { - if (!EvaluateComplex(this, Result.Val, Info)) - return false; - } else - return false; - - return true; -} - -bool Expr::EvaluateAsAny(EvalResult &Result, ASTContext &Ctx) const { - EvalInfo Info(Ctx, Result, true); - - if (getType()->isVectorType()) { - if (!EvaluateVector(this, Result.Val, Info)) - return false; - } else if (getType()->isIntegerType()) { - if (!IntExprEvaluator(Info, Result.Val).Visit(const_cast<Expr*>(this))) + } else if (E->getType()->hasPointerRepresentation()) { + LValue LV; + if (!EvaluatePointer(E, LV, Info)) return false; - } else if (getType()->hasPointerRepresentation()) { - if (!EvaluatePointer(this, Result.Val, Info)) + if (!IsGlobalLValue(LV.Base)) return false; - } else if (getType()->isRealFloatingType()) { - llvm::APFloat f(0.0); - if (!EvaluateFloat(this, f, Info)) + LV.moveInto(Info.EvalResult.Val); + } else if (E->getType()->isRealFloatingType()) { + llvm::APFloat F(0.0); + if (!EvaluateFloat(E, F, Info)) return false; - Result.Val = APValue(f); - } else if (getType()->isAnyComplexType()) { - if (!EvaluateComplex(this, Result.Val, Info)) + Info.EvalResult.Val = APValue(F); + } else if (E->getType()->isAnyComplexType()) { + ComplexValue C; + if (!EvaluateComplex(E, C, Info)) return false; + C.moveInto(Info.EvalResult.Val); } else return false; @@ -2128,13 +2220,25 @@ bool Expr::EvaluateAsBooleanCondition(bool &Result, ASTContext &Ctx) const { bool Expr::EvaluateAsLValue(EvalResult &Result, ASTContext &Ctx) const { EvalInfo Info(Ctx, Result); - return EvaluateLValue(this, Result.Val, Info) && !Result.HasSideEffects; + LValue LV; + if (EvaluateLValue(this, LV, Info) && + !Result.HasSideEffects && + IsGlobalLValue(LV.Base)) { + LV.moveInto(Result.Val); + return true; + } + return false; } bool Expr::EvaluateAsAnyLValue(EvalResult &Result, ASTContext &Ctx) const { - EvalInfo Info(Ctx, Result, true); + EvalInfo Info(Ctx, Result); - return EvaluateLValue(this, Result.Val, Info) && !Result.HasSideEffects; + LValue LV; + if (EvaluateLValue(this, LV, Info)) { + LV.moveInto(Result.Val); + return true; + } + return false; } /// isEvaluatable - Call Evaluate to see if this expression can be constant @@ -2159,3 +2263,388 @@ APSInt Expr::EvaluateAsInt(ASTContext &Ctx) const { return EvalResult.Val.getInt(); } + + bool Expr::EvalResult::isGlobalLValue() const { + assert(Val.isLValue()); + return IsGlobalLValue(Val.getLValueBase()); + } + + +/// isIntegerConstantExpr - this recursive routine will test if an expression is +/// an integer constant expression. + +/// FIXME: Pass up a reason why! Invalid operation in i-c-e, division by zero, +/// comma, etc +/// +/// FIXME: Handle offsetof. Two things to do: Handle GCC's __builtin_offsetof +/// to support gcc 4.0+ and handle the idiom GCC recognizes with a null pointer +/// cast+dereference. + +// CheckICE - This function does the fundamental ICE checking: the returned +// ICEDiag contains a Val of 0, 1, or 2, and a possibly null SourceLocation. +// Note that to reduce code duplication, this helper does no evaluation +// itself; the caller checks whether the expression is evaluatable, and +// in the rare cases where CheckICE actually cares about the evaluated +// value, it calls into Evalute. +// +// Meanings of Val: +// 0: This expression is an ICE if it can be evaluated by Evaluate. +// 1: This expression is not an ICE, but if it isn't evaluated, it's +// a legal subexpression for an ICE. This return value is used to handle +// the comma operator in C99 mode. +// 2: This expression is not an ICE, and is not a legal subexpression for one. + +struct ICEDiag { + unsigned Val; + SourceLocation Loc; + + public: + ICEDiag(unsigned v, SourceLocation l) : Val(v), Loc(l) {} + ICEDiag() : Val(0) {} +}; + +ICEDiag NoDiag() { return ICEDiag(); } + +static ICEDiag CheckEvalInICE(const Expr* E, ASTContext &Ctx) { + Expr::EvalResult EVResult; + if (!E->Evaluate(EVResult, Ctx) || EVResult.HasSideEffects || + !EVResult.Val.isInt()) { + return ICEDiag(2, E->getLocStart()); + } + return NoDiag(); +} + +static ICEDiag CheckICE(const Expr* E, ASTContext &Ctx) { + assert(!E->isValueDependent() && "Should not see value dependent exprs!"); + if (!E->getType()->isIntegralType()) { + return ICEDiag(2, E->getLocStart()); + } + + switch (E->getStmtClass()) { +#define STMT(Node, Base) case Expr::Node##Class: +#define EXPR(Node, Base) +#include "clang/AST/StmtNodes.inc" + case Expr::PredefinedExprClass: + case Expr::FloatingLiteralClass: + case Expr::ImaginaryLiteralClass: + case Expr::StringLiteralClass: + case Expr::ArraySubscriptExprClass: + case Expr::MemberExprClass: + case Expr::CompoundAssignOperatorClass: + case Expr::CompoundLiteralExprClass: + case Expr::ExtVectorElementExprClass: + case Expr::InitListExprClass: + case Expr::DesignatedInitExprClass: + case Expr::ImplicitValueInitExprClass: + case Expr::ParenListExprClass: + case Expr::VAArgExprClass: + case Expr::AddrLabelExprClass: + case Expr::StmtExprClass: + case Expr::CXXMemberCallExprClass: + case Expr::CXXDynamicCastExprClass: + case Expr::CXXTypeidExprClass: + case Expr::CXXNullPtrLiteralExprClass: + case Expr::CXXThisExprClass: + case Expr::CXXThrowExprClass: + case Expr::CXXNewExprClass: + case Expr::CXXDeleteExprClass: + case Expr::CXXPseudoDestructorExprClass: + case Expr::UnresolvedLookupExprClass: + case Expr::DependentScopeDeclRefExprClass: + case Expr::CXXConstructExprClass: + case Expr::CXXBindTemporaryExprClass: + case Expr::CXXBindReferenceExprClass: + case Expr::CXXExprWithTemporariesClass: + case Expr::CXXTemporaryObjectExprClass: + case Expr::CXXUnresolvedConstructExprClass: + case Expr::CXXDependentScopeMemberExprClass: + case Expr::UnresolvedMemberExprClass: + case Expr::ObjCStringLiteralClass: + case Expr::ObjCEncodeExprClass: + case Expr::ObjCMessageExprClass: + case Expr::ObjCSelectorExprClass: + case Expr::ObjCProtocolExprClass: + case Expr::ObjCIvarRefExprClass: + case Expr::ObjCPropertyRefExprClass: + case Expr::ObjCImplicitSetterGetterRefExprClass: + case Expr::ObjCSuperExprClass: + case Expr::ObjCIsaExprClass: + case Expr::ShuffleVectorExprClass: + case Expr::BlockExprClass: + case Expr::BlockDeclRefExprClass: + case Expr::NoStmtClass: + return ICEDiag(2, E->getLocStart()); + + case Expr::GNUNullExprClass: + // GCC considers the GNU __null value to be an integral constant expression. + return NoDiag(); + + case Expr::ParenExprClass: + return CheckICE(cast<ParenExpr>(E)->getSubExpr(), Ctx); + case Expr::IntegerLiteralClass: + case Expr::CharacterLiteralClass: + case Expr::CXXBoolLiteralExprClass: + case Expr::CXXZeroInitValueExprClass: + case Expr::TypesCompatibleExprClass: + case Expr::UnaryTypeTraitExprClass: + return NoDiag(); + case Expr::CallExprClass: + case Expr::CXXOperatorCallExprClass: { + const CallExpr *CE = cast<CallExpr>(E); + if (CE->isBuiltinCall(Ctx)) + return CheckEvalInICE(E, Ctx); + return ICEDiag(2, E->getLocStart()); + } + case Expr::DeclRefExprClass: + if (isa<EnumConstantDecl>(cast<DeclRefExpr>(E)->getDecl())) + return NoDiag(); + if (Ctx.getLangOptions().CPlusPlus && + E->getType().getCVRQualifiers() == Qualifiers::Const) { + const NamedDecl *D = cast<DeclRefExpr>(E)->getDecl(); + + // Parameter variables are never constants. Without this check, + // getAnyInitializer() can find a default argument, which leads + // to chaos. + if (isa<ParmVarDecl>(D)) + return ICEDiag(2, cast<DeclRefExpr>(E)->getLocation()); + + // C++ 7.1.5.1p2 + // A variable of non-volatile const-qualified integral or enumeration + // type initialized by an ICE can be used in ICEs. + if (const VarDecl *Dcl = dyn_cast<VarDecl>(D)) { + Qualifiers Quals = Ctx.getCanonicalType(Dcl->getType()).getQualifiers(); + if (Quals.hasVolatile() || !Quals.hasConst()) + return ICEDiag(2, cast<DeclRefExpr>(E)->getLocation()); + + // Look for a declaration of this variable that has an initializer. + const VarDecl *ID = 0; + const Expr *Init = Dcl->getAnyInitializer(ID); + if (Init) { + if (ID->isInitKnownICE()) { + // We have already checked whether this subexpression is an + // integral constant expression. + if (ID->isInitICE()) + return NoDiag(); + else + return ICEDiag(2, cast<DeclRefExpr>(E)->getLocation()); + } + + // It's an ICE whether or not the definition we found is + // out-of-line. See DR 721 and the discussion in Clang PR + // 6206 for details. + + if (Dcl->isCheckingICE()) { + return ICEDiag(2, cast<DeclRefExpr>(E)->getLocation()); + } + + Dcl->setCheckingICE(); + ICEDiag Result = CheckICE(Init, Ctx); + // Cache the result of the ICE test. + Dcl->setInitKnownICE(Result.Val == 0); + return Result; + } + } + } + return ICEDiag(2, E->getLocStart()); + case Expr::UnaryOperatorClass: { + const UnaryOperator *Exp = cast<UnaryOperator>(E); + switch (Exp->getOpcode()) { + case UnaryOperator::PostInc: + case UnaryOperator::PostDec: + case UnaryOperator::PreInc: + case UnaryOperator::PreDec: + case UnaryOperator::AddrOf: + case UnaryOperator::Deref: + return ICEDiag(2, E->getLocStart()); + case UnaryOperator::Extension: + case UnaryOperator::LNot: + case UnaryOperator::Plus: + case UnaryOperator::Minus: + case UnaryOperator::Not: + case UnaryOperator::Real: + case UnaryOperator::Imag: + return CheckICE(Exp->getSubExpr(), Ctx); + case UnaryOperator::OffsetOf: + break; + } + + // OffsetOf falls through here. + } + case Expr::OffsetOfExprClass: { + // Note that per C99, offsetof must be an ICE. And AFAIK, using + // Evaluate matches the proposed gcc behavior for cases like + // "offsetof(struct s{int x[4];}, x[!.0])". This doesn't affect + // compliance: we should warn earlier for offsetof expressions with + // array subscripts that aren't ICEs, and if the array subscripts + // are ICEs, the value of the offsetof must be an integer constant. + return CheckEvalInICE(E, Ctx); + } + case Expr::SizeOfAlignOfExprClass: { + const SizeOfAlignOfExpr *Exp = cast<SizeOfAlignOfExpr>(E); + if (Exp->isSizeOf() && Exp->getTypeOfArgument()->isVariableArrayType()) + return ICEDiag(2, E->getLocStart()); + return NoDiag(); + } + case Expr::BinaryOperatorClass: { + const BinaryOperator *Exp = cast<BinaryOperator>(E); + switch (Exp->getOpcode()) { + case BinaryOperator::PtrMemD: + case BinaryOperator::PtrMemI: + case BinaryOperator::Assign: + case BinaryOperator::MulAssign: + case BinaryOperator::DivAssign: + case BinaryOperator::RemAssign: + case BinaryOperator::AddAssign: + case BinaryOperator::SubAssign: + case BinaryOperator::ShlAssign: + case BinaryOperator::ShrAssign: + case BinaryOperator::AndAssign: + case BinaryOperator::XorAssign: + case BinaryOperator::OrAssign: + return ICEDiag(2, E->getLocStart()); + + case BinaryOperator::Mul: + case BinaryOperator::Div: + case BinaryOperator::Rem: + case BinaryOperator::Add: + case BinaryOperator::Sub: + case BinaryOperator::Shl: + case BinaryOperator::Shr: + case BinaryOperator::LT: + case BinaryOperator::GT: + case BinaryOperator::LE: + case BinaryOperator::GE: + case BinaryOperator::EQ: + case BinaryOperator::NE: + case BinaryOperator::And: + case BinaryOperator::Xor: + case BinaryOperator::Or: + case BinaryOperator::Comma: { + ICEDiag LHSResult = CheckICE(Exp->getLHS(), Ctx); + ICEDiag RHSResult = CheckICE(Exp->getRHS(), Ctx); + if (Exp->getOpcode() == BinaryOperator::Div || + Exp->getOpcode() == BinaryOperator::Rem) { + // Evaluate gives an error for undefined Div/Rem, so make sure + // we don't evaluate one. + if (LHSResult.Val != 2 && RHSResult.Val != 2) { + llvm::APSInt REval = Exp->getRHS()->EvaluateAsInt(Ctx); + if (REval == 0) + return ICEDiag(1, E->getLocStart()); + if (REval.isSigned() && REval.isAllOnesValue()) { + llvm::APSInt LEval = Exp->getLHS()->EvaluateAsInt(Ctx); + if (LEval.isMinSignedValue()) + return ICEDiag(1, E->getLocStart()); + } + } + } + if (Exp->getOpcode() == BinaryOperator::Comma) { + if (Ctx.getLangOptions().C99) { + // C99 6.6p3 introduces a strange edge case: comma can be in an ICE + // if it isn't evaluated. + if (LHSResult.Val == 0 && RHSResult.Val == 0) + return ICEDiag(1, E->getLocStart()); + } else { + // In both C89 and C++, commas in ICEs are illegal. + return ICEDiag(2, E->getLocStart()); + } + } + if (LHSResult.Val >= RHSResult.Val) + return LHSResult; + return RHSResult; + } + case BinaryOperator::LAnd: + case BinaryOperator::LOr: { + ICEDiag LHSResult = CheckICE(Exp->getLHS(), Ctx); + ICEDiag RHSResult = CheckICE(Exp->getRHS(), Ctx); + if (LHSResult.Val == 0 && RHSResult.Val == 1) { + // Rare case where the RHS has a comma "side-effect"; we need + // to actually check the condition to see whether the side + // with the comma is evaluated. + if ((Exp->getOpcode() == BinaryOperator::LAnd) != + (Exp->getLHS()->EvaluateAsInt(Ctx) == 0)) + return RHSResult; + return NoDiag(); + } + + if (LHSResult.Val >= RHSResult.Val) + return LHSResult; + return RHSResult; + } + } + } + case Expr::ImplicitCastExprClass: + case Expr::CStyleCastExprClass: + case Expr::CXXFunctionalCastExprClass: + case Expr::CXXStaticCastExprClass: + case Expr::CXXReinterpretCastExprClass: + case Expr::CXXConstCastExprClass: { + const Expr *SubExpr = cast<CastExpr>(E)->getSubExpr(); + if (SubExpr->getType()->isIntegralType()) + return CheckICE(SubExpr, Ctx); + if (isa<FloatingLiteral>(SubExpr->IgnoreParens())) + return NoDiag(); + return ICEDiag(2, E->getLocStart()); + } + case Expr::ConditionalOperatorClass: { + const ConditionalOperator *Exp = cast<ConditionalOperator>(E); + // If the condition (ignoring parens) is a __builtin_constant_p call, + // then only the true side is actually considered in an integer constant + // expression, and it is fully evaluated. This is an important GNU + // extension. See GCC PR38377 for discussion. + if (const CallExpr *CallCE + = dyn_cast<CallExpr>(Exp->getCond()->IgnoreParenCasts())) + if (CallCE->isBuiltinCall(Ctx) == Builtin::BI__builtin_constant_p) { + Expr::EvalResult EVResult; + if (!E->Evaluate(EVResult, Ctx) || EVResult.HasSideEffects || + !EVResult.Val.isInt()) { + return ICEDiag(2, E->getLocStart()); + } + return NoDiag(); + } + ICEDiag CondResult = CheckICE(Exp->getCond(), Ctx); + ICEDiag TrueResult = CheckICE(Exp->getTrueExpr(), Ctx); + ICEDiag FalseResult = CheckICE(Exp->getFalseExpr(), Ctx); + if (CondResult.Val == 2) + return CondResult; + if (TrueResult.Val == 2) + return TrueResult; + if (FalseResult.Val == 2) + return FalseResult; + if (CondResult.Val == 1) + return CondResult; + if (TrueResult.Val == 0 && FalseResult.Val == 0) + return NoDiag(); + // Rare case where the diagnostics depend on which side is evaluated + // Note that if we get here, CondResult is 0, and at least one of + // TrueResult and FalseResult is non-zero. + if (Exp->getCond()->EvaluateAsInt(Ctx) == 0) { + return FalseResult; + } + return TrueResult; + } + case Expr::CXXDefaultArgExprClass: + return CheckICE(cast<CXXDefaultArgExpr>(E)->getExpr(), Ctx); + case Expr::ChooseExprClass: { + return CheckICE(cast<ChooseExpr>(E)->getChosenSubExpr(Ctx), Ctx); + } + } + + // Silence a GCC warning + return ICEDiag(2, E->getLocStart()); +} + +bool Expr::isIntegerConstantExpr(llvm::APSInt &Result, ASTContext &Ctx, + SourceLocation *Loc, bool isEvaluated) const { + ICEDiag d = CheckICE(this, Ctx); + if (d.Val != 0) { + if (Loc) *Loc = d.Loc; + return false; + } + EvalResult EvalResult; + if (!Evaluate(EvalResult, Ctx)) + llvm_unreachable("ICE cannot be evaluated!"); + assert(!EvalResult.HasSideEffects && "ICE with side effects!"); + assert(EvalResult.Val.isInt() && "ICE that isn't integer!"); + Result = EvalResult.Val.getInt(); + return true; +} |
