| //===--- SemaStmt.cpp - Semantic Analysis for Statements ------------------===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file implements semantic analysis for statements. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "Sema.h" |
| #include "SemaInit.h" |
| #include "clang/AST/APValue.h" |
| #include "clang/AST/ASTContext.h" |
| #include "clang/AST/DeclObjC.h" |
| #include "clang/AST/ExprCXX.h" |
| #include "clang/AST/ExprObjC.h" |
| #include "clang/AST/StmtObjC.h" |
| #include "clang/AST/StmtCXX.h" |
| #include "clang/Lex/Preprocessor.h" |
| #include "clang/Basic/TargetInfo.h" |
| #include "llvm/ADT/STLExtras.h" |
| #include "llvm/ADT/SmallVector.h" |
| using namespace clang; |
| |
| Sema::OwningStmtResult Sema::ActOnExprStmt(FullExprArg expr) { |
| Expr *E = expr->takeAs<Expr>(); |
| assert(E && "ActOnExprStmt(): missing expression"); |
| if (E->getType()->isObjCInterfaceType()) { |
| if (LangOpts.ObjCNonFragileABI) |
| Diag(E->getLocEnd(), diag::err_indirection_requires_nonfragile_object) |
| << E->getType(); |
| else |
| Diag(E->getLocEnd(), diag::err_direct_interface_unsupported) |
| << E->getType(); |
| return StmtError(); |
| } |
| // C99 6.8.3p2: The expression in an expression statement is evaluated as a |
| // void expression for its side effects. Conversion to void allows any |
| // operand, even incomplete types. |
| |
| // Same thing in for stmt first clause (when expr) and third clause. |
| return Owned(static_cast<Stmt*>(E)); |
| } |
| |
| |
| Sema::OwningStmtResult Sema::ActOnNullStmt(SourceLocation SemiLoc) { |
| return Owned(new (Context) NullStmt(SemiLoc)); |
| } |
| |
| Sema::OwningStmtResult Sema::ActOnDeclStmt(DeclGroupPtrTy dg, |
| SourceLocation StartLoc, |
| SourceLocation EndLoc) { |
| DeclGroupRef DG = dg.getAsVal<DeclGroupRef>(); |
| |
| // If we have an invalid decl, just return an error. |
| if (DG.isNull()) return StmtError(); |
| |
| return Owned(new (Context) DeclStmt(DG, StartLoc, EndLoc)); |
| } |
| |
| void Sema::ActOnForEachDeclStmt(DeclGroupPtrTy dg) { |
| DeclGroupRef DG = dg.getAsVal<DeclGroupRef>(); |
| |
| // If we have an invalid decl, just return. |
| if (DG.isNull() || !DG.isSingleDecl()) return; |
| // suppress any potential 'unused variable' warning. |
| DG.getSingleDecl()->setUsed(); |
| } |
| |
| void Sema::DiagnoseUnusedExprResult(const Stmt *S) { |
| const Expr *E = dyn_cast_or_null<Expr>(S); |
| if (!E) |
| return; |
| |
| // Ignore expressions that have void type. |
| if (E->getType()->isVoidType()) |
| return; |
| |
| SourceLocation Loc; |
| SourceRange R1, R2; |
| if (!E->isUnusedResultAWarning(Loc, R1, R2, Context)) |
| return; |
| |
| // Okay, we have an unused result. Depending on what the base expression is, |
| // we might want to make a more specific diagnostic. Check for one of these |
| // cases now. |
| unsigned DiagID = diag::warn_unused_expr; |
| E = E->IgnoreParens(); |
| if (isa<ObjCImplicitSetterGetterRefExpr>(E)) |
| DiagID = diag::warn_unused_property_expr; |
| |
| if (const CallExpr *CE = dyn_cast<CallExpr>(E)) { |
| // If the callee has attribute pure, const, or warn_unused_result, warn with |
| // a more specific message to make it clear what is happening. |
| if (const Decl *FD = CE->getCalleeDecl()) { |
| if (FD->getAttr<WarnUnusedResultAttr>()) { |
| Diag(Loc, diag::warn_unused_call) << R1 << R2 << "warn_unused_result"; |
| return; |
| } |
| if (FD->getAttr<PureAttr>()) { |
| Diag(Loc, diag::warn_unused_call) << R1 << R2 << "pure"; |
| return; |
| } |
| if (FD->getAttr<ConstAttr>()) { |
| Diag(Loc, diag::warn_unused_call) << R1 << R2 << "const"; |
| return; |
| } |
| } |
| } |
| |
| Diag(Loc, DiagID) << R1 << R2; |
| } |
| |
| Action::OwningStmtResult |
| Sema::ActOnCompoundStmt(SourceLocation L, SourceLocation R, |
| MultiStmtArg elts, bool isStmtExpr) { |
| unsigned NumElts = elts.size(); |
| Stmt **Elts = reinterpret_cast<Stmt**>(elts.release()); |
| // If we're in C89 mode, check that we don't have any decls after stmts. If |
| // so, emit an extension diagnostic. |
| if (!getLangOptions().C99 && !getLangOptions().CPlusPlus) { |
| // Note that __extension__ can be around a decl. |
| unsigned i = 0; |
| // Skip over all declarations. |
| for (; i != NumElts && isa<DeclStmt>(Elts[i]); ++i) |
| /*empty*/; |
| |
| // We found the end of the list or a statement. Scan for another declstmt. |
| for (; i != NumElts && !isa<DeclStmt>(Elts[i]); ++i) |
| /*empty*/; |
| |
| if (i != NumElts) { |
| Decl *D = *cast<DeclStmt>(Elts[i])->decl_begin(); |
| Diag(D->getLocation(), diag::ext_mixed_decls_code); |
| } |
| } |
| // Warn about unused expressions in statements. |
| for (unsigned i = 0; i != NumElts; ++i) { |
| // Ignore statements that are last in a statement expression. |
| if (isStmtExpr && i == NumElts - 1) |
| continue; |
| |
| DiagnoseUnusedExprResult(Elts[i]); |
| } |
| |
| return Owned(new (Context) CompoundStmt(Context, Elts, NumElts, L, R)); |
| } |
| |
| Action::OwningStmtResult |
| Sema::ActOnCaseStmt(SourceLocation CaseLoc, ExprArg lhsval, |
| SourceLocation DotDotDotLoc, ExprArg rhsval, |
| SourceLocation ColonLoc) { |
| assert((lhsval.get() != 0) && "missing expression in case statement"); |
| |
| // C99 6.8.4.2p3: The expression shall be an integer constant. |
| // However, GCC allows any evaluatable integer expression. |
| Expr *LHSVal = static_cast<Expr*>(lhsval.get()); |
| if (!LHSVal->isTypeDependent() && !LHSVal->isValueDependent() && |
| VerifyIntegerConstantExpression(LHSVal)) |
| return StmtError(); |
| |
| // GCC extension: The expression shall be an integer constant. |
| |
| Expr *RHSVal = static_cast<Expr*>(rhsval.get()); |
| if (RHSVal && !RHSVal->isTypeDependent() && !RHSVal->isValueDependent() && |
| VerifyIntegerConstantExpression(RHSVal)) { |
| RHSVal = 0; // Recover by just forgetting about it. |
| rhsval = 0; |
| } |
| |
| if (getSwitchStack().empty()) { |
| Diag(CaseLoc, diag::err_case_not_in_switch); |
| return StmtError(); |
| } |
| |
| // Only now release the smart pointers. |
| lhsval.release(); |
| rhsval.release(); |
| CaseStmt *CS = new (Context) CaseStmt(LHSVal, RHSVal, CaseLoc, DotDotDotLoc, |
| ColonLoc); |
| getSwitchStack().back()->addSwitchCase(CS); |
| return Owned(CS); |
| } |
| |
| /// ActOnCaseStmtBody - This installs a statement as the body of a case. |
| void Sema::ActOnCaseStmtBody(StmtTy *caseStmt, StmtArg subStmt) { |
| CaseStmt *CS = static_cast<CaseStmt*>(caseStmt); |
| Stmt *SubStmt = subStmt.takeAs<Stmt>(); |
| CS->setSubStmt(SubStmt); |
| } |
| |
| Action::OwningStmtResult |
| Sema::ActOnDefaultStmt(SourceLocation DefaultLoc, SourceLocation ColonLoc, |
| StmtArg subStmt, Scope *CurScope) { |
| Stmt *SubStmt = subStmt.takeAs<Stmt>(); |
| |
| if (getSwitchStack().empty()) { |
| Diag(DefaultLoc, diag::err_default_not_in_switch); |
| return Owned(SubStmt); |
| } |
| |
| DefaultStmt *DS = new (Context) DefaultStmt(DefaultLoc, ColonLoc, SubStmt); |
| getSwitchStack().back()->addSwitchCase(DS); |
| return Owned(DS); |
| } |
| |
| Action::OwningStmtResult |
| Sema::ActOnLabelStmt(SourceLocation IdentLoc, IdentifierInfo *II, |
| SourceLocation ColonLoc, StmtArg subStmt) { |
| Stmt *SubStmt = subStmt.takeAs<Stmt>(); |
| // Look up the record for this label identifier. |
| LabelStmt *&LabelDecl = getLabelMap()[II]; |
| |
| // If not forward referenced or defined already, just create a new LabelStmt. |
| if (LabelDecl == 0) |
| return Owned(LabelDecl = new (Context) LabelStmt(IdentLoc, II, SubStmt)); |
| |
| assert(LabelDecl->getID() == II && "Label mismatch!"); |
| |
| // Otherwise, this label was either forward reference or multiply defined. If |
| // multiply defined, reject it now. |
| if (LabelDecl->getSubStmt()) { |
| Diag(IdentLoc, diag::err_redefinition_of_label) << LabelDecl->getID(); |
| Diag(LabelDecl->getIdentLoc(), diag::note_previous_definition); |
| return Owned(SubStmt); |
| } |
| |
| // Otherwise, this label was forward declared, and we just found its real |
| // definition. Fill in the forward definition and return it. |
| LabelDecl->setIdentLoc(IdentLoc); |
| LabelDecl->setSubStmt(SubStmt); |
| return Owned(LabelDecl); |
| } |
| |
| Action::OwningStmtResult |
| Sema::ActOnIfStmt(SourceLocation IfLoc, FullExprArg CondVal, DeclPtrTy CondVar, |
| StmtArg ThenVal, SourceLocation ElseLoc, |
| StmtArg ElseVal) { |
| OwningExprResult CondResult(CondVal.release()); |
| |
| VarDecl *ConditionVar = 0; |
| if (CondVar.get()) { |
| ConditionVar = CondVar.getAs<VarDecl>(); |
| CondResult = CheckConditionVariable(ConditionVar); |
| if (CondResult.isInvalid()) |
| return StmtError(); |
| } |
| Expr *ConditionExpr = CondResult.takeAs<Expr>(); |
| if (!ConditionExpr) |
| return StmtError(); |
| |
| if (CheckBooleanCondition(ConditionExpr, IfLoc)) { |
| CondResult = ConditionExpr; |
| return StmtError(); |
| } |
| |
| Stmt *thenStmt = ThenVal.takeAs<Stmt>(); |
| DiagnoseUnusedExprResult(thenStmt); |
| |
| // Warn if the if block has a null body without an else value. |
| // this helps prevent bugs due to typos, such as |
| // if (condition); |
| // do_stuff(); |
| if (!ElseVal.get()) { |
| if (NullStmt* stmt = dyn_cast<NullStmt>(thenStmt)) |
| Diag(stmt->getSemiLoc(), diag::warn_empty_if_body); |
| } |
| |
| Stmt *elseStmt = ElseVal.takeAs<Stmt>(); |
| DiagnoseUnusedExprResult(elseStmt); |
| |
| CondResult.release(); |
| return Owned(new (Context) IfStmt(IfLoc, ConditionVar, ConditionExpr, |
| thenStmt, ElseLoc, elseStmt)); |
| } |
| |
| Action::OwningStmtResult |
| Sema::ActOnStartOfSwitchStmt(FullExprArg cond, DeclPtrTy CondVar) { |
| OwningExprResult CondResult(cond.release()); |
| |
| VarDecl *ConditionVar = 0; |
| if (CondVar.get()) { |
| ConditionVar = CondVar.getAs<VarDecl>(); |
| CondResult = CheckConditionVariable(ConditionVar); |
| if (CondResult.isInvalid()) |
| return StmtError(); |
| } |
| SwitchStmt *SS = new (Context) SwitchStmt(ConditionVar, |
| CondResult.takeAs<Expr>()); |
| getSwitchStack().push_back(SS); |
| return Owned(SS); |
| } |
| |
| /// ConvertIntegerToTypeWarnOnOverflow - Convert the specified APInt to have |
| /// the specified width and sign. If an overflow occurs, detect it and emit |
| /// the specified diagnostic. |
| void Sema::ConvertIntegerToTypeWarnOnOverflow(llvm::APSInt &Val, |
| unsigned NewWidth, bool NewSign, |
| SourceLocation Loc, |
| unsigned DiagID) { |
| // Perform a conversion to the promoted condition type if needed. |
| if (NewWidth > Val.getBitWidth()) { |
| // If this is an extension, just do it. |
| llvm::APSInt OldVal(Val); |
| Val.extend(NewWidth); |
| |
| // If the input was signed and negative and the output is unsigned, |
| // warn. |
| if (!NewSign && OldVal.isSigned() && OldVal.isNegative()) |
| Diag(Loc, DiagID) << OldVal.toString(10) << Val.toString(10); |
| |
| Val.setIsSigned(NewSign); |
| } else if (NewWidth < Val.getBitWidth()) { |
| // If this is a truncation, check for overflow. |
| llvm::APSInt ConvVal(Val); |
| ConvVal.trunc(NewWidth); |
| ConvVal.setIsSigned(NewSign); |
| ConvVal.extend(Val.getBitWidth()); |
| ConvVal.setIsSigned(Val.isSigned()); |
| if (ConvVal != Val) |
| Diag(Loc, DiagID) << Val.toString(10) << ConvVal.toString(10); |
| |
| // Regardless of whether a diagnostic was emitted, really do the |
| // truncation. |
| Val.trunc(NewWidth); |
| Val.setIsSigned(NewSign); |
| } else if (NewSign != Val.isSigned()) { |
| // Convert the sign to match the sign of the condition. This can cause |
| // overflow as well: unsigned(INTMIN) |
| llvm::APSInt OldVal(Val); |
| Val.setIsSigned(NewSign); |
| |
| if (Val.isNegative()) // Sign bit changes meaning. |
| Diag(Loc, DiagID) << OldVal.toString(10) << Val.toString(10); |
| } |
| } |
| |
| namespace { |
| struct CaseCompareFunctor { |
| bool operator()(const std::pair<llvm::APSInt, CaseStmt*> &LHS, |
| const llvm::APSInt &RHS) { |
| return LHS.first < RHS; |
| } |
| bool operator()(const std::pair<llvm::APSInt, CaseStmt*> &LHS, |
| const std::pair<llvm::APSInt, CaseStmt*> &RHS) { |
| return LHS.first < RHS.first; |
| } |
| bool operator()(const llvm::APSInt &LHS, |
| const std::pair<llvm::APSInt, CaseStmt*> &RHS) { |
| return LHS < RHS.first; |
| } |
| }; |
| } |
| |
| /// CmpCaseVals - Comparison predicate for sorting case values. |
| /// |
| static bool CmpCaseVals(const std::pair<llvm::APSInt, CaseStmt*>& lhs, |
| const std::pair<llvm::APSInt, CaseStmt*>& rhs) { |
| if (lhs.first < rhs.first) |
| return true; |
| |
| if (lhs.first == rhs.first && |
| lhs.second->getCaseLoc().getRawEncoding() |
| < rhs.second->getCaseLoc().getRawEncoding()) |
| return true; |
| return false; |
| } |
| |
| /// GetTypeBeforeIntegralPromotion - Returns the pre-promotion type of |
| /// potentially integral-promoted expression @p expr. |
| static QualType GetTypeBeforeIntegralPromotion(const Expr* expr) { |
| const ImplicitCastExpr *ImplicitCast = |
| dyn_cast_or_null<ImplicitCastExpr>(expr); |
| if (ImplicitCast != NULL) { |
| const Expr *ExprBeforePromotion = ImplicitCast->getSubExpr(); |
| QualType TypeBeforePromotion = ExprBeforePromotion->getType(); |
| if (TypeBeforePromotion->isIntegralType()) { |
| return TypeBeforePromotion; |
| } |
| } |
| return expr->getType(); |
| } |
| |
| /// \brief Check (and possibly convert) the condition in a switch |
| /// statement in C++. |
| static bool CheckCXXSwitchCondition(Sema &S, SourceLocation SwitchLoc, |
| Expr *&CondExpr) { |
| if (CondExpr->isTypeDependent()) |
| return false; |
| |
| QualType CondType = CondExpr->getType(); |
| |
| // C++ 6.4.2.p2: |
| // The condition shall be of integral type, enumeration type, or of a class |
| // type for which a single conversion function to integral or enumeration |
| // type exists (12.3). If the condition is of class type, the condition is |
| // converted by calling that conversion function, and the result of the |
| // conversion is used in place of the original condition for the remainder |
| // of this section. Integral promotions are performed. |
| |
| // Make sure that the condition expression has a complete type, |
| // otherwise we'll never find any conversions. |
| if (S.RequireCompleteType(SwitchLoc, CondType, |
| PDiag(diag::err_switch_incomplete_class_type) |
| << CondExpr->getSourceRange())) |
| return true; |
| |
| llvm::SmallVector<CXXConversionDecl *, 4> ViableConversions; |
| llvm::SmallVector<CXXConversionDecl *, 4> ExplicitConversions; |
| if (const RecordType *RecordTy = CondType->getAs<RecordType>()) { |
| const UnresolvedSetImpl *Conversions |
| = cast<CXXRecordDecl>(RecordTy->getDecl()) |
| ->getVisibleConversionFunctions(); |
| for (UnresolvedSetImpl::iterator I = Conversions->begin(), |
| E = Conversions->end(); I != E; ++I) { |
| if (CXXConversionDecl *Conversion = dyn_cast<CXXConversionDecl>(*I)) |
| if (Conversion->getConversionType().getNonReferenceType() |
| ->isIntegralType()) { |
| if (Conversion->isExplicit()) |
| ExplicitConversions.push_back(Conversion); |
| else |
| ViableConversions.push_back(Conversion); |
| } |
| } |
| |
| switch (ViableConversions.size()) { |
| case 0: |
| if (ExplicitConversions.size() == 1) { |
| // The user probably meant to invoke the given explicit |
| // conversion; use it. |
| QualType ConvTy |
| = ExplicitConversions[0]->getConversionType() |
| .getNonReferenceType(); |
| std::string TypeStr; |
| ConvTy.getAsStringInternal(TypeStr, S.Context.PrintingPolicy); |
| |
| S.Diag(SwitchLoc, diag::err_switch_explicit_conversion) |
| << CondType << ConvTy << CondExpr->getSourceRange() |
| << CodeModificationHint::CreateInsertion(CondExpr->getLocStart(), |
| "static_cast<" + TypeStr + ">(") |
| << CodeModificationHint::CreateInsertion( |
| S.PP.getLocForEndOfToken(CondExpr->getLocEnd()), |
| ")"); |
| S.Diag(ExplicitConversions[0]->getLocation(), |
| diag::note_switch_conversion) |
| << ConvTy->isEnumeralType() << ConvTy; |
| |
| // If we aren't in a SFINAE context, build a call to the |
| // explicit conversion function. |
| if (S.isSFINAEContext()) |
| return true; |
| |
| CondExpr = S.BuildCXXMemberCallExpr(CondExpr, ExplicitConversions[0]); |
| } |
| |
| // We'll complain below about a non-integral condition type. |
| break; |
| |
| case 1: |
| // Apply this conversion. |
| CondExpr = S.BuildCXXMemberCallExpr(CondExpr, ViableConversions[0]); |
| break; |
| |
| default: |
| S.Diag(SwitchLoc, diag::err_switch_multiple_conversions) |
| << CondType << CondExpr->getSourceRange(); |
| for (unsigned I = 0, N = ViableConversions.size(); I != N; ++I) { |
| QualType ConvTy |
| = ViableConversions[I]->getConversionType().getNonReferenceType(); |
| S.Diag(ViableConversions[I]->getLocation(), |
| diag::note_switch_conversion) |
| << ConvTy->isEnumeralType() << ConvTy; |
| } |
| return true; |
| } |
| } |
| |
| return false; |
| } |
| |
| /// ActOnSwitchBodyError - This is called if there is an error parsing the |
| /// body of the switch stmt instead of ActOnFinishSwitchStmt. |
| void Sema::ActOnSwitchBodyError(SourceLocation SwitchLoc, StmtArg Switch, |
| StmtArg Body) { |
| // Keep the switch stack balanced. |
| assert(getSwitchStack().back() == (SwitchStmt*)Switch.get() && |
| "switch stack missing push/pop!"); |
| getSwitchStack().pop_back(); |
| } |
| |
| Action::OwningStmtResult |
| Sema::ActOnFinishSwitchStmt(SourceLocation SwitchLoc, StmtArg Switch, |
| StmtArg Body) { |
| Stmt *BodyStmt = Body.takeAs<Stmt>(); |
| |
| SwitchStmt *SS = getSwitchStack().back(); |
| assert(SS == (SwitchStmt*)Switch.get() && "switch stack missing push/pop!"); |
| |
| SS->setBody(BodyStmt, SwitchLoc); |
| getSwitchStack().pop_back(); |
| |
| if (SS->getCond() == 0) { |
| SS->Destroy(Context); |
| return StmtError(); |
| } |
| |
| Expr *CondExpr = SS->getCond(); |
| QualType CondTypeBeforePromotion = |
| GetTypeBeforeIntegralPromotion(CondExpr); |
| |
| if (getLangOptions().CPlusPlus && |
| CheckCXXSwitchCondition(*this, SwitchLoc, CondExpr)) |
| return StmtError(); |
| |
| // C99 6.8.4.2p5 - Integer promotions are performed on the controlling expr. |
| UsualUnaryConversions(CondExpr); |
| QualType CondType = CondExpr->getType(); |
| SS->setCond(CondExpr); |
| |
| // C++ 6.4.2.p2: |
| // Integral promotions are performed (on the switch condition). |
| // |
| // A case value unrepresentable by the original switch condition |
| // type (before the promotion) doesn't make sense, even when it can |
| // be represented by the promoted type. Therefore we need to find |
| // the pre-promotion type of the switch condition. |
| if (!CondExpr->isTypeDependent()) { |
| if (!CondType->isIntegerType()) { // C99 6.8.4.2p1 |
| Diag(SwitchLoc, diag::err_typecheck_statement_requires_integer) |
| << CondType << CondExpr->getSourceRange(); |
| return StmtError(); |
| } |
| |
| if (CondTypeBeforePromotion->isBooleanType()) { |
| // switch(bool_expr) {...} is often a programmer error, e.g. |
| // switch(n && mask) { ... } // Doh - should be "n & mask". |
| // One can always use an if statement instead of switch(bool_expr). |
| Diag(SwitchLoc, diag::warn_bool_switch_condition) |
| << CondExpr->getSourceRange(); |
| } |
| } |
| |
| // Get the bitwidth of the switched-on value before promotions. We must |
| // convert the integer case values to this width before comparison. |
| bool HasDependentValue |
| = CondExpr->isTypeDependent() || CondExpr->isValueDependent(); |
| unsigned CondWidth |
| = HasDependentValue? 0 |
| : static_cast<unsigned>(Context.getTypeSize(CondTypeBeforePromotion)); |
| bool CondIsSigned = CondTypeBeforePromotion->isSignedIntegerType(); |
| |
| // Accumulate all of the case values in a vector so that we can sort them |
| // and detect duplicates. This vector contains the APInt for the case after |
| // it has been converted to the condition type. |
| typedef llvm::SmallVector<std::pair<llvm::APSInt, CaseStmt*>, 64> CaseValsTy; |
| CaseValsTy CaseVals; |
| |
| // Keep track of any GNU case ranges we see. The APSInt is the low value. |
| std::vector<std::pair<llvm::APSInt, CaseStmt*> > CaseRanges; |
| |
| DefaultStmt *TheDefaultStmt = 0; |
| |
| bool CaseListIsErroneous = false; |
| |
| for (SwitchCase *SC = SS->getSwitchCaseList(); SC && !HasDependentValue; |
| SC = SC->getNextSwitchCase()) { |
| |
| if (DefaultStmt *DS = dyn_cast<DefaultStmt>(SC)) { |
| if (TheDefaultStmt) { |
| Diag(DS->getDefaultLoc(), diag::err_multiple_default_labels_defined); |
| Diag(TheDefaultStmt->getDefaultLoc(), diag::note_duplicate_case_prev); |
| |
| // FIXME: Remove the default statement from the switch block so that |
| // we'll return a valid AST. This requires recursing down the AST and |
| // finding it, not something we are set up to do right now. For now, |
| // just lop the entire switch stmt out of the AST. |
| CaseListIsErroneous = true; |
| } |
| TheDefaultStmt = DS; |
| |
| } else { |
| CaseStmt *CS = cast<CaseStmt>(SC); |
| |
| // We already verified that the expression has a i-c-e value (C99 |
| // 6.8.4.2p3) - get that value now. |
| Expr *Lo = CS->getLHS(); |
| |
| if (Lo->isTypeDependent() || Lo->isValueDependent()) { |
| HasDependentValue = true; |
| break; |
| } |
| |
| llvm::APSInt LoVal = Lo->EvaluateAsInt(Context); |
| |
| // Convert the value to the same width/sign as the condition. |
| ConvertIntegerToTypeWarnOnOverflow(LoVal, CondWidth, CondIsSigned, |
| CS->getLHS()->getLocStart(), |
| diag::warn_case_value_overflow); |
| |
| // If the LHS is not the same type as the condition, insert an implicit |
| // cast. |
| ImpCastExprToType(Lo, CondType, CastExpr::CK_IntegralCast); |
| CS->setLHS(Lo); |
| |
| // If this is a case range, remember it in CaseRanges, otherwise CaseVals. |
| if (CS->getRHS()) { |
| if (CS->getRHS()->isTypeDependent() || |
| CS->getRHS()->isValueDependent()) { |
| HasDependentValue = true; |
| break; |
| } |
| CaseRanges.push_back(std::make_pair(LoVal, CS)); |
| } else |
| CaseVals.push_back(std::make_pair(LoVal, CS)); |
| } |
| } |
| |
| if (!HasDependentValue) { |
| // Sort all the scalar case values so we can easily detect duplicates. |
| std::stable_sort(CaseVals.begin(), CaseVals.end(), CmpCaseVals); |
| |
| if (!CaseVals.empty()) { |
| for (unsigned i = 0, e = CaseVals.size()-1; i != e; ++i) { |
| if (CaseVals[i].first == CaseVals[i+1].first) { |
| // If we have a duplicate, report it. |
| Diag(CaseVals[i+1].second->getLHS()->getLocStart(), |
| diag::err_duplicate_case) << CaseVals[i].first.toString(10); |
| Diag(CaseVals[i].second->getLHS()->getLocStart(), |
| diag::note_duplicate_case_prev); |
| // FIXME: We really want to remove the bogus case stmt from the |
| // substmt, but we have no way to do this right now. |
| CaseListIsErroneous = true; |
| } |
| } |
| } |
| |
| // Detect duplicate case ranges, which usually don't exist at all in |
| // the first place. |
| if (!CaseRanges.empty()) { |
| // Sort all the case ranges by their low value so we can easily detect |
| // overlaps between ranges. |
| std::stable_sort(CaseRanges.begin(), CaseRanges.end()); |
| |
| // Scan the ranges, computing the high values and removing empty ranges. |
| std::vector<llvm::APSInt> HiVals; |
| for (unsigned i = 0, e = CaseRanges.size(); i != e; ++i) { |
| CaseStmt *CR = CaseRanges[i].second; |
| Expr *Hi = CR->getRHS(); |
| llvm::APSInt HiVal = Hi->EvaluateAsInt(Context); |
| |
| // Convert the value to the same width/sign as the condition. |
| ConvertIntegerToTypeWarnOnOverflow(HiVal, CondWidth, CondIsSigned, |
| CR->getRHS()->getLocStart(), |
| diag::warn_case_value_overflow); |
| |
| // If the LHS is not the same type as the condition, insert an implicit |
| // cast. |
| ImpCastExprToType(Hi, CondType, CastExpr::CK_IntegralCast); |
| CR->setRHS(Hi); |
| |
| // If the low value is bigger than the high value, the case is empty. |
| if (CaseRanges[i].first > HiVal) { |
| Diag(CR->getLHS()->getLocStart(), diag::warn_case_empty_range) |
| << SourceRange(CR->getLHS()->getLocStart(), |
| CR->getRHS()->getLocEnd()); |
| CaseRanges.erase(CaseRanges.begin()+i); |
| --i, --e; |
| continue; |
| } |
| HiVals.push_back(HiVal); |
| } |
| |
| // Rescan the ranges, looking for overlap with singleton values and other |
| // ranges. Since the range list is sorted, we only need to compare case |
| // ranges with their neighbors. |
| for (unsigned i = 0, e = CaseRanges.size(); i != e; ++i) { |
| llvm::APSInt &CRLo = CaseRanges[i].first; |
| llvm::APSInt &CRHi = HiVals[i]; |
| CaseStmt *CR = CaseRanges[i].second; |
| |
| // Check to see whether the case range overlaps with any |
| // singleton cases. |
| CaseStmt *OverlapStmt = 0; |
| llvm::APSInt OverlapVal(32); |
| |
| // Find the smallest value >= the lower bound. If I is in the |
| // case range, then we have overlap. |
| CaseValsTy::iterator I = std::lower_bound(CaseVals.begin(), |
| CaseVals.end(), CRLo, |
| CaseCompareFunctor()); |
| if (I != CaseVals.end() && I->first < CRHi) { |
| OverlapVal = I->first; // Found overlap with scalar. |
| OverlapStmt = I->second; |
| } |
| |
| // Find the smallest value bigger than the upper bound. |
| I = std::upper_bound(I, CaseVals.end(), CRHi, CaseCompareFunctor()); |
| if (I != CaseVals.begin() && (I-1)->first >= CRLo) { |
| OverlapVal = (I-1)->first; // Found overlap with scalar. |
| OverlapStmt = (I-1)->second; |
| } |
| |
| // Check to see if this case stmt overlaps with the subsequent |
| // case range. |
| if (i && CRLo <= HiVals[i-1]) { |
| OverlapVal = HiVals[i-1]; // Found overlap with range. |
| OverlapStmt = CaseRanges[i-1].second; |
| } |
| |
| if (OverlapStmt) { |
| // If we have a duplicate, report it. |
| Diag(CR->getLHS()->getLocStart(), diag::err_duplicate_case) |
| << OverlapVal.toString(10); |
| Diag(OverlapStmt->getLHS()->getLocStart(), |
| diag::note_duplicate_case_prev); |
| // FIXME: We really want to remove the bogus case stmt from the |
| // substmt, but we have no way to do this right now. |
| CaseListIsErroneous = true; |
| } |
| } |
| } |
| } |
| |
| // FIXME: If the case list was broken is some way, we don't have a good system |
| // to patch it up. Instead, just return the whole substmt as broken. |
| if (CaseListIsErroneous) |
| return StmtError(); |
| |
| Switch.release(); |
| return Owned(SS); |
| } |
| |
| Action::OwningStmtResult |
| Sema::ActOnWhileStmt(SourceLocation WhileLoc, FullExprArg Cond, |
| DeclPtrTy CondVar, StmtArg Body) { |
| OwningExprResult CondResult(Cond.release()); |
| |
| VarDecl *ConditionVar = 0; |
| if (CondVar.get()) { |
| ConditionVar = CondVar.getAs<VarDecl>(); |
| CondResult = CheckConditionVariable(ConditionVar); |
| if (CondResult.isInvalid()) |
| return StmtError(); |
| } |
| Expr *ConditionExpr = CondResult.takeAs<Expr>(); |
| if (!ConditionExpr) |
| return StmtError(); |
| |
| if (CheckBooleanCondition(ConditionExpr, WhileLoc)) { |
| CondResult = ConditionExpr; |
| return StmtError(); |
| } |
| |
| Stmt *bodyStmt = Body.takeAs<Stmt>(); |
| DiagnoseUnusedExprResult(bodyStmt); |
| |
| CondResult.release(); |
| return Owned(new (Context) WhileStmt(ConditionVar, ConditionExpr, bodyStmt, |
| WhileLoc)); |
| } |
| |
| Action::OwningStmtResult |
| Sema::ActOnDoStmt(SourceLocation DoLoc, StmtArg Body, |
| SourceLocation WhileLoc, SourceLocation CondLParen, |
| ExprArg Cond, SourceLocation CondRParen) { |
| Expr *condExpr = Cond.takeAs<Expr>(); |
| assert(condExpr && "ActOnDoStmt(): missing expression"); |
| |
| if (CheckBooleanCondition(condExpr, DoLoc)) { |
| Cond = condExpr; |
| return StmtError(); |
| } |
| |
| Stmt *bodyStmt = Body.takeAs<Stmt>(); |
| DiagnoseUnusedExprResult(bodyStmt); |
| |
| Cond.release(); |
| return Owned(new (Context) DoStmt(bodyStmt, condExpr, DoLoc, |
| WhileLoc, CondRParen)); |
| } |
| |
| Action::OwningStmtResult |
| Sema::ActOnForStmt(SourceLocation ForLoc, SourceLocation LParenLoc, |
| StmtArg first, FullExprArg second, DeclPtrTy secondVar, |
| FullExprArg third, |
| SourceLocation RParenLoc, StmtArg body) { |
| Stmt *First = static_cast<Stmt*>(first.get()); |
| |
| if (!getLangOptions().CPlusPlus) { |
| if (DeclStmt *DS = dyn_cast_or_null<DeclStmt>(First)) { |
| // C99 6.8.5p3: The declaration part of a 'for' statement shall only |
| // declare identifiers for objects having storage class 'auto' or |
| // 'register'. |
| for (DeclStmt::decl_iterator DI=DS->decl_begin(), DE=DS->decl_end(); |
| DI!=DE; ++DI) { |
| VarDecl *VD = dyn_cast<VarDecl>(*DI); |
| if (VD && VD->isBlockVarDecl() && !VD->hasLocalStorage()) |
| VD = 0; |
| if (VD == 0) |
| Diag((*DI)->getLocation(), diag::err_non_variable_decl_in_for); |
| // FIXME: mark decl erroneous! |
| } |
| } |
| } |
| |
| OwningExprResult SecondResult(second.release()); |
| VarDecl *ConditionVar = 0; |
| if (secondVar.get()) { |
| ConditionVar = secondVar.getAs<VarDecl>(); |
| SecondResult = CheckConditionVariable(ConditionVar); |
| if (SecondResult.isInvalid()) |
| return StmtError(); |
| } |
| |
| Expr *Second = SecondResult.takeAs<Expr>(); |
| if (Second && CheckBooleanCondition(Second, ForLoc)) { |
| SecondResult = Second; |
| return StmtError(); |
| } |
| |
| Expr *Third = third.release().takeAs<Expr>(); |
| Stmt *Body = static_cast<Stmt*>(body.get()); |
| |
| DiagnoseUnusedExprResult(First); |
| DiagnoseUnusedExprResult(Third); |
| DiagnoseUnusedExprResult(Body); |
| |
| first.release(); |
| body.release(); |
| return Owned(new (Context) ForStmt(First, Second, ConditionVar, Third, Body, |
| ForLoc, LParenLoc, RParenLoc)); |
| } |
| |
| Action::OwningStmtResult |
| Sema::ActOnObjCForCollectionStmt(SourceLocation ForLoc, |
| SourceLocation LParenLoc, |
| StmtArg first, ExprArg second, |
| SourceLocation RParenLoc, StmtArg body) { |
| Stmt *First = static_cast<Stmt*>(first.get()); |
| Expr *Second = static_cast<Expr*>(second.get()); |
| Stmt *Body = static_cast<Stmt*>(body.get()); |
| if (First) { |
| QualType FirstType; |
| if (DeclStmt *DS = dyn_cast<DeclStmt>(First)) { |
| if (!DS->isSingleDecl()) |
| return StmtError(Diag((*DS->decl_begin())->getLocation(), |
| diag::err_toomany_element_decls)); |
| |
| Decl *D = DS->getSingleDecl(); |
| FirstType = cast<ValueDecl>(D)->getType(); |
| // C99 6.8.5p3: The declaration part of a 'for' statement shall only |
| // declare identifiers for objects having storage class 'auto' or |
| // 'register'. |
| VarDecl *VD = cast<VarDecl>(D); |
| if (VD->isBlockVarDecl() && !VD->hasLocalStorage()) |
| return StmtError(Diag(VD->getLocation(), |
| diag::err_non_variable_decl_in_for)); |
| } else { |
| if (cast<Expr>(First)->isLvalue(Context) != Expr::LV_Valid) |
| return StmtError(Diag(First->getLocStart(), |
| diag::err_selector_element_not_lvalue) |
| << First->getSourceRange()); |
| |
| FirstType = static_cast<Expr*>(First)->getType(); |
| } |
| if (!FirstType->isObjCObjectPointerType() && |
| !FirstType->isBlockPointerType()) |
| Diag(ForLoc, diag::err_selector_element_type) |
| << FirstType << First->getSourceRange(); |
| } |
| if (Second) { |
| DefaultFunctionArrayConversion(Second); |
| QualType SecondType = Second->getType(); |
| if (!SecondType->isObjCObjectPointerType()) |
| Diag(ForLoc, diag::err_collection_expr_type) |
| << SecondType << Second->getSourceRange(); |
| } |
| first.release(); |
| second.release(); |
| body.release(); |
| return Owned(new (Context) ObjCForCollectionStmt(First, Second, Body, |
| ForLoc, RParenLoc)); |
| } |
| |
| Action::OwningStmtResult |
| Sema::ActOnGotoStmt(SourceLocation GotoLoc, SourceLocation LabelLoc, |
| IdentifierInfo *LabelII) { |
| // Look up the record for this label identifier. |
| LabelStmt *&LabelDecl = getLabelMap()[LabelII]; |
| |
| // If we haven't seen this label yet, create a forward reference. |
| if (LabelDecl == 0) |
| LabelDecl = new (Context) LabelStmt(LabelLoc, LabelII, 0); |
| |
| return Owned(new (Context) GotoStmt(LabelDecl, GotoLoc, LabelLoc)); |
| } |
| |
| Action::OwningStmtResult |
| Sema::ActOnIndirectGotoStmt(SourceLocation GotoLoc, SourceLocation StarLoc, |
| ExprArg DestExp) { |
| // Convert operand to void* |
| Expr* E = DestExp.takeAs<Expr>(); |
| if (!E->isTypeDependent()) { |
| QualType ETy = E->getType(); |
| AssignConvertType ConvTy = |
| CheckSingleAssignmentConstraints(Context.VoidPtrTy, E); |
| if (DiagnoseAssignmentResult(ConvTy, StarLoc, Context.VoidPtrTy, ETy, |
| E, AA_Passing)) |
| return StmtError(); |
| } |
| return Owned(new (Context) IndirectGotoStmt(GotoLoc, StarLoc, E)); |
| } |
| |
| Action::OwningStmtResult |
| Sema::ActOnContinueStmt(SourceLocation ContinueLoc, Scope *CurScope) { |
| Scope *S = CurScope->getContinueParent(); |
| if (!S) { |
| // C99 6.8.6.2p1: A break shall appear only in or as a loop body. |
| return StmtError(Diag(ContinueLoc, diag::err_continue_not_in_loop)); |
| } |
| |
| return Owned(new (Context) ContinueStmt(ContinueLoc)); |
| } |
| |
| Action::OwningStmtResult |
| Sema::ActOnBreakStmt(SourceLocation BreakLoc, Scope *CurScope) { |
| Scope *S = CurScope->getBreakParent(); |
| if (!S) { |
| // C99 6.8.6.3p1: A break shall appear only in or as a switch/loop body. |
| return StmtError(Diag(BreakLoc, diag::err_break_not_in_loop_or_switch)); |
| } |
| |
| return Owned(new (Context) BreakStmt(BreakLoc)); |
| } |
| |
| /// ActOnBlockReturnStmt - Utility routine to figure out block's return type. |
| /// |
| Action::OwningStmtResult |
| Sema::ActOnBlockReturnStmt(SourceLocation ReturnLoc, Expr *RetValExp) { |
| // If this is the first return we've seen in the block, infer the type of |
| // the block from it. |
| if (CurBlock->ReturnType.isNull()) { |
| if (RetValExp) { |
| // Don't call UsualUnaryConversions(), since we don't want to do |
| // integer promotions here. |
| DefaultFunctionArrayConversion(RetValExp); |
| CurBlock->ReturnType = RetValExp->getType(); |
| if (BlockDeclRefExpr *CDRE = dyn_cast<BlockDeclRefExpr>(RetValExp)) { |
| // We have to remove a 'const' added to copied-in variable which was |
| // part of the implementation spec. and not the actual qualifier for |
| // the variable. |
| if (CDRE->isConstQualAdded()) |
| CurBlock->ReturnType.removeConst(); |
| } |
| } else |
| CurBlock->ReturnType = Context.VoidTy; |
| } |
| QualType FnRetType = CurBlock->ReturnType; |
| |
| if (CurBlock->TheDecl->hasAttr<NoReturnAttr>()) { |
| Diag(ReturnLoc, diag::err_noreturn_block_has_return_expr) |
| << getCurFunctionOrMethodDecl()->getDeclName(); |
| return StmtError(); |
| } |
| |
| // Otherwise, verify that this result type matches the previous one. We are |
| // pickier with blocks than for normal functions because we don't have GCC |
| // compatibility to worry about here. |
| if (CurBlock->ReturnType->isVoidType()) { |
| if (RetValExp) { |
| Diag(ReturnLoc, diag::err_return_block_has_expr); |
| RetValExp->Destroy(Context); |
| RetValExp = 0; |
| } |
| return Owned(new (Context) ReturnStmt(ReturnLoc, RetValExp)); |
| } |
| |
| if (!RetValExp) |
| return StmtError(Diag(ReturnLoc, diag::err_block_return_missing_expr)); |
| |
| if (!FnRetType->isDependentType() && !RetValExp->isTypeDependent()) { |
| // we have a non-void block with an expression, continue checking |
| |
| // C99 6.8.6.4p3(136): The return statement is not an assignment. The |
| // overlap restriction of subclause 6.5.16.1 does not apply to the case of |
| // function return. |
| |
| // In C++ the return statement is handled via a copy initialization. |
| // the C version of which boils down to CheckSingleAssignmentConstraints. |
| // FIXME: Leaks RetValExp. |
| if (PerformCopyInitialization(RetValExp, FnRetType, AA_Returning)) |
| return StmtError(); |
| |
| if (RetValExp) CheckReturnStackAddr(RetValExp, FnRetType, ReturnLoc); |
| } |
| |
| return Owned(new (Context) ReturnStmt(ReturnLoc, RetValExp)); |
| } |
| |
| /// IsReturnCopyElidable - Whether returning @p RetExpr from a function that |
| /// returns a @p RetType fulfills the criteria for copy elision (C++0x 12.8p15). |
| static bool IsReturnCopyElidable(ASTContext &Ctx, QualType RetType, |
| Expr *RetExpr) { |
| QualType ExprType = RetExpr->getType(); |
| // - in a return statement in a function with ... |
| // ... a class return type ... |
| if (!RetType->isRecordType()) |
| return false; |
| // ... the same cv-unqualified type as the function return type ... |
| if (!Ctx.hasSameUnqualifiedType(RetType, ExprType)) |
| return false; |
| // ... the expression is the name of a non-volatile automatic object ... |
| // We ignore parentheses here. |
| // FIXME: Is this compliant? |
| const DeclRefExpr *DR = dyn_cast<DeclRefExpr>(RetExpr->IgnoreParens()); |
| if (!DR) |
| return false; |
| const VarDecl *VD = dyn_cast<VarDecl>(DR->getDecl()); |
| if (!VD) |
| return false; |
| return VD->hasLocalStorage() && !VD->getType()->isReferenceType() |
| && !VD->getType().isVolatileQualified(); |
| } |
| |
| Action::OwningStmtResult |
| Sema::ActOnReturnStmt(SourceLocation ReturnLoc, ExprArg rex) { |
| Expr *RetValExp = rex.takeAs<Expr>(); |
| if (CurBlock) |
| return ActOnBlockReturnStmt(ReturnLoc, RetValExp); |
| |
| QualType FnRetType; |
| if (const FunctionDecl *FD = getCurFunctionDecl()) { |
| FnRetType = FD->getResultType(); |
| if (FD->hasAttr<NoReturnAttr>()) |
| Diag(ReturnLoc, diag::warn_noreturn_function_has_return_expr) |
| << getCurFunctionOrMethodDecl()->getDeclName(); |
| } else if (ObjCMethodDecl *MD = getCurMethodDecl()) |
| FnRetType = MD->getResultType(); |
| else // If we don't have a function/method context, bail. |
| return StmtError(); |
| |
| if (FnRetType->isVoidType()) { |
| if (RetValExp && !RetValExp->isTypeDependent()) { |
| // C99 6.8.6.4p1 (ext_ since GCC warns) |
| unsigned D = diag::ext_return_has_expr; |
| if (RetValExp->getType()->isVoidType()) |
| D = diag::ext_return_has_void_expr; |
| |
| // return (some void expression); is legal in C++. |
| if (D != diag::ext_return_has_void_expr || |
| !getLangOptions().CPlusPlus) { |
| NamedDecl *CurDecl = getCurFunctionOrMethodDecl(); |
| Diag(ReturnLoc, D) |
| << CurDecl->getDeclName() << isa<ObjCMethodDecl>(CurDecl) |
| << RetValExp->getSourceRange(); |
| } |
| |
| RetValExp = MaybeCreateCXXExprWithTemporaries(RetValExp); |
| } |
| return Owned(new (Context) ReturnStmt(ReturnLoc, RetValExp)); |
| } |
| |
| if (!RetValExp && !FnRetType->isDependentType()) { |
| unsigned DiagID = diag::warn_return_missing_expr; // C90 6.6.6.4p4 |
| // C99 6.8.6.4p1 (ext_ since GCC warns) |
| if (getLangOptions().C99) DiagID = diag::ext_return_missing_expr; |
| |
| if (FunctionDecl *FD = getCurFunctionDecl()) |
| Diag(ReturnLoc, DiagID) << FD->getIdentifier() << 0/*fn*/; |
| else |
| Diag(ReturnLoc, DiagID) << getCurMethodDecl()->getDeclName() << 1/*meth*/; |
| return Owned(new (Context) ReturnStmt(ReturnLoc, (Expr*)0)); |
| } |
| |
| if (!FnRetType->isDependentType() && !RetValExp->isTypeDependent()) { |
| // we have a non-void function with an expression, continue checking |
| |
| // C99 6.8.6.4p3(136): The return statement is not an assignment. The |
| // overlap restriction of subclause 6.5.16.1 does not apply to the case of |
| // function return. |
| |
| // C++0x 12.8p15: When certain criteria are met, an implementation is |
| // allowed to omit the copy construction of a class object, [...] |
| // - in a return statement in a function with a class return type, when |
| // the expression is the name of a non-volatile automatic object with |
| // the same cv-unqualified type as the function return type, the copy |
| // operation can be omitted [...] |
| // C++0x 12.8p16: When the criteria for elision of a copy operation are met |
| // and the object to be copied is designated by an lvalue, overload |
| // resolution to select the constructor for the copy is first performed |
| // as if the object were designated by an rvalue. |
| // Note that we only compute Elidable if we're in C++0x, since we don't |
| // care otherwise. |
| bool Elidable = getLangOptions().CPlusPlus0x ? |
| IsReturnCopyElidable(Context, FnRetType, RetValExp) : |
| false; |
| // FIXME: Elidable |
| (void)Elidable; |
| |
| // In C++ the return statement is handled via a copy initialization. |
| // the C version of which boils down to CheckSingleAssignmentConstraints. |
| OwningExprResult Res = PerformCopyInitialization( |
| InitializedEntity::InitializeResult(ReturnLoc, |
| FnRetType), |
| SourceLocation(), |
| Owned(RetValExp)); |
| if (Res.isInvalid()) { |
| // FIXME: Cleanup temporaries here, anyway? |
| return StmtError(); |
| } |
| |
| RetValExp = Res.takeAs<Expr>(); |
| if (RetValExp) |
| CheckReturnStackAddr(RetValExp, FnRetType, ReturnLoc); |
| } |
| |
| if (RetValExp) |
| RetValExp = MaybeCreateCXXExprWithTemporaries(RetValExp); |
| return Owned(new (Context) ReturnStmt(ReturnLoc, RetValExp)); |
| } |
| |
| /// CheckAsmLValue - GNU C has an extremely ugly extension whereby they silently |
| /// ignore "noop" casts in places where an lvalue is required by an inline asm. |
| /// We emulate this behavior when -fheinous-gnu-extensions is specified, but |
| /// provide a strong guidance to not use it. |
| /// |
| /// This method checks to see if the argument is an acceptable l-value and |
| /// returns false if it is a case we can handle. |
| static bool CheckAsmLValue(const Expr *E, Sema &S) { |
| // Type dependent expressions will be checked during instantiation. |
| if (E->isTypeDependent()) |
| return false; |
| |
| if (E->isLvalue(S.Context) == Expr::LV_Valid) |
| return false; // Cool, this is an lvalue. |
| |
| // Okay, this is not an lvalue, but perhaps it is the result of a cast that we |
| // are supposed to allow. |
| const Expr *E2 = E->IgnoreParenNoopCasts(S.Context); |
| if (E != E2 && E2->isLvalue(S.Context) == Expr::LV_Valid) { |
| if (!S.getLangOptions().HeinousExtensions) |
| S.Diag(E2->getLocStart(), diag::err_invalid_asm_cast_lvalue) |
| << E->getSourceRange(); |
| else |
| S.Diag(E2->getLocStart(), diag::warn_invalid_asm_cast_lvalue) |
| << E->getSourceRange(); |
| // Accept, even if we emitted an error diagnostic. |
| return false; |
| } |
| |
| // None of the above, just randomly invalid non-lvalue. |
| return true; |
| } |
| |
| |
| Sema::OwningStmtResult Sema::ActOnAsmStmt(SourceLocation AsmLoc, |
| bool IsSimple, |
| bool IsVolatile, |
| unsigned NumOutputs, |
| unsigned NumInputs, |
| const std::string *Names, |
| MultiExprArg constraints, |
| MultiExprArg exprs, |
| ExprArg asmString, |
| MultiExprArg clobbers, |
| SourceLocation RParenLoc, |
| bool MSAsm) { |
| unsigned NumClobbers = clobbers.size(); |
| StringLiteral **Constraints = |
| reinterpret_cast<StringLiteral**>(constraints.get()); |
| Expr **Exprs = reinterpret_cast<Expr **>(exprs.get()); |
| StringLiteral *AsmString = cast<StringLiteral>((Expr *)asmString.get()); |
| StringLiteral **Clobbers = reinterpret_cast<StringLiteral**>(clobbers.get()); |
| |
| llvm::SmallVector<TargetInfo::ConstraintInfo, 4> OutputConstraintInfos; |
| |
| // The parser verifies that there is a string literal here. |
| if (AsmString->isWide()) |
| return StmtError(Diag(AsmString->getLocStart(),diag::err_asm_wide_character) |
| << AsmString->getSourceRange()); |
| |
| for (unsigned i = 0; i != NumOutputs; i++) { |
| StringLiteral *Literal = Constraints[i]; |
| if (Literal->isWide()) |
| return StmtError(Diag(Literal->getLocStart(),diag::err_asm_wide_character) |
| << Literal->getSourceRange()); |
| |
| TargetInfo::ConstraintInfo Info(Literal->getStrData(), |
| Literal->getByteLength(), |
| Names[i]); |
| if (!Context.Target.validateOutputConstraint(Info)) |
| return StmtError(Diag(Literal->getLocStart(), |
| diag::err_asm_invalid_output_constraint) |
| << Info.getConstraintStr()); |
| |
| // Check that the output exprs are valid lvalues. |
| Expr *OutputExpr = Exprs[i]; |
| if (CheckAsmLValue(OutputExpr, *this)) { |
| return StmtError(Diag(OutputExpr->getLocStart(), |
| diag::err_asm_invalid_lvalue_in_output) |
| << OutputExpr->getSourceRange()); |
| } |
| |
| OutputConstraintInfos.push_back(Info); |
| } |
| |
| llvm::SmallVector<TargetInfo::ConstraintInfo, 4> InputConstraintInfos; |
| |
| for (unsigned i = NumOutputs, e = NumOutputs + NumInputs; i != e; i++) { |
| StringLiteral *Literal = Constraints[i]; |
| if (Literal->isWide()) |
| return StmtError(Diag(Literal->getLocStart(),diag::err_asm_wide_character) |
| << Literal->getSourceRange()); |
| |
| TargetInfo::ConstraintInfo Info(Literal->getStrData(), |
| Literal->getByteLength(), |
| Names[i]); |
| if (!Context.Target.validateInputConstraint(OutputConstraintInfos.data(), |
| NumOutputs, Info)) { |
| return StmtError(Diag(Literal->getLocStart(), |
| diag::err_asm_invalid_input_constraint) |
| << Info.getConstraintStr()); |
| } |
| |
| Expr *InputExpr = Exprs[i]; |
| |
| // Only allow void types for memory constraints. |
| if (Info.allowsMemory() && !Info.allowsRegister()) { |
| if (CheckAsmLValue(InputExpr, *this)) |
| return StmtError(Diag(InputExpr->getLocStart(), |
| diag::err_asm_invalid_lvalue_in_input) |
| << Info.getConstraintStr() |
| << InputExpr->getSourceRange()); |
| } |
| |
| if (Info.allowsRegister()) { |
| if (InputExpr->getType()->isVoidType()) { |
| return StmtError(Diag(InputExpr->getLocStart(), |
| diag::err_asm_invalid_type_in_input) |
| << InputExpr->getType() << Info.getConstraintStr() |
| << InputExpr->getSourceRange()); |
| } |
| } |
| |
| DefaultFunctionArrayConversion(Exprs[i]); |
| |
| InputConstraintInfos.push_back(Info); |
| } |
| |
| // Check that the clobbers are valid. |
| for (unsigned i = 0; i != NumClobbers; i++) { |
| StringLiteral *Literal = Clobbers[i]; |
| if (Literal->isWide()) |
| return StmtError(Diag(Literal->getLocStart(),diag::err_asm_wide_character) |
| << Literal->getSourceRange()); |
| |
| std::string Clobber(Literal->getStrData(), |
| Literal->getStrData() + |
| Literal->getByteLength()); |
| |
| if (!Context.Target.isValidGCCRegisterName(Clobber.c_str())) |
| return StmtError(Diag(Literal->getLocStart(), |
| diag::err_asm_unknown_register_name) << Clobber); |
| } |
| |
| constraints.release(); |
| exprs.release(); |
| asmString.release(); |
| clobbers.release(); |
| AsmStmt *NS = |
| new (Context) AsmStmt(AsmLoc, IsSimple, IsVolatile, MSAsm, NumOutputs, |
| NumInputs, Names, Constraints, Exprs, AsmString, |
| NumClobbers, Clobbers, RParenLoc); |
| // Validate the asm string, ensuring it makes sense given the operands we |
| // have. |
| llvm::SmallVector<AsmStmt::AsmStringPiece, 8> Pieces; |
| unsigned DiagOffs; |
| if (unsigned DiagID = NS->AnalyzeAsmString(Pieces, Context, DiagOffs)) { |
| Diag(getLocationOfStringLiteralByte(AsmString, DiagOffs), DiagID) |
| << AsmString->getSourceRange(); |
| DeleteStmt(NS); |
| return StmtError(); |
| } |
| |
| // Validate tied input operands for type mismatches. |
| for (unsigned i = 0, e = InputConstraintInfos.size(); i != e; ++i) { |
| TargetInfo::ConstraintInfo &Info = InputConstraintInfos[i]; |
| |
| // If this is a tied constraint, verify that the output and input have |
| // either exactly the same type, or that they are int/ptr operands with the |
| // same size (int/long, int*/long, are ok etc). |
| if (!Info.hasTiedOperand()) continue; |
| |
| unsigned TiedTo = Info.getTiedOperand(); |
| Expr *OutputExpr = Exprs[TiedTo]; |
| Expr *InputExpr = Exprs[i+NumOutputs]; |
| QualType InTy = InputExpr->getType(); |
| QualType OutTy = OutputExpr->getType(); |
| if (Context.hasSameType(InTy, OutTy)) |
| continue; // All types can be tied to themselves. |
| |
| // Int/ptr operands have some special cases that we allow. |
| if ((OutTy->isIntegerType() || OutTy->isPointerType()) && |
| (InTy->isIntegerType() || InTy->isPointerType())) { |
| |
| // They are ok if they are the same size. Tying void* to int is ok if |
| // they are the same size, for example. This also allows tying void* to |
| // int*. |
| uint64_t OutSize = Context.getTypeSize(OutTy); |
| uint64_t InSize = Context.getTypeSize(InTy); |
| if (OutSize == InSize) |
| continue; |
| |
| // If the smaller input/output operand is not mentioned in the asm string, |
| // then we can promote it and the asm string won't notice. Check this |
| // case now. |
| bool SmallerValueMentioned = false; |
| for (unsigned p = 0, e = Pieces.size(); p != e; ++p) { |
| AsmStmt::AsmStringPiece &Piece = Pieces[p]; |
| if (!Piece.isOperand()) continue; |
| |
| // If this is a reference to the input and if the input was the smaller |
| // one, then we have to reject this asm. |
| if (Piece.getOperandNo() == i+NumOutputs) { |
| if (InSize < OutSize) { |
| SmallerValueMentioned = true; |
| break; |
| } |
| } |
| |
| // If this is a reference to the input and if the input was the smaller |
| // one, then we have to reject this asm. |
| if (Piece.getOperandNo() == TiedTo) { |
| if (InSize > OutSize) { |
| SmallerValueMentioned = true; |
| break; |
| } |
| } |
| } |
| |
| // If the smaller value wasn't mentioned in the asm string, and if the |
| // output was a register, just extend the shorter one to the size of the |
| // larger one. |
| if (!SmallerValueMentioned && |
| OutputConstraintInfos[TiedTo].allowsRegister()) |
| continue; |
| } |
| |
| Diag(InputExpr->getLocStart(), |
| diag::err_asm_tying_incompatible_types) |
| << InTy << OutTy << OutputExpr->getSourceRange() |
| << InputExpr->getSourceRange(); |
| DeleteStmt(NS); |
| return StmtError(); |
| } |
| |
| return Owned(NS); |
| } |
| |
| Action::OwningStmtResult |
| Sema::ActOnObjCAtCatchStmt(SourceLocation AtLoc, |
| SourceLocation RParen, DeclPtrTy Parm, |
| StmtArg Body, StmtArg catchList) { |
| Stmt *CatchList = catchList.takeAs<Stmt>(); |
| ParmVarDecl *PVD = cast_or_null<ParmVarDecl>(Parm.getAs<Decl>()); |
| |
| // PVD == 0 implies @catch(...). |
| if (PVD) { |
| // If we already know the decl is invalid, reject it. |
| if (PVD->isInvalidDecl()) |
| return StmtError(); |
| |
| if (!PVD->getType()->isObjCObjectPointerType()) |
| return StmtError(Diag(PVD->getLocation(), |
| diag::err_catch_param_not_objc_type)); |
| if (PVD->getType()->isObjCQualifiedIdType()) |
| return StmtError(Diag(PVD->getLocation(), |
| diag::err_illegal_qualifiers_on_catch_parm)); |
| } |
| |
| ObjCAtCatchStmt *CS = new (Context) ObjCAtCatchStmt(AtLoc, RParen, |
| PVD, Body.takeAs<Stmt>(), CatchList); |
| return Owned(CatchList ? CatchList : CS); |
| } |
| |
| Action::OwningStmtResult |
| Sema::ActOnObjCAtFinallyStmt(SourceLocation AtLoc, StmtArg Body) { |
| return Owned(new (Context) ObjCAtFinallyStmt(AtLoc, |
| static_cast<Stmt*>(Body.release()))); |
| } |
| |
| Action::OwningStmtResult |
| Sema::ActOnObjCAtTryStmt(SourceLocation AtLoc, |
| StmtArg Try, StmtArg Catch, StmtArg Finally) { |
| CurFunctionNeedsScopeChecking = true; |
| return Owned(new (Context) ObjCAtTryStmt(AtLoc, Try.takeAs<Stmt>(), |
| Catch.takeAs<Stmt>(), |
| Finally.takeAs<Stmt>())); |
| } |
| |
| Action::OwningStmtResult |
| Sema::ActOnObjCAtThrowStmt(SourceLocation AtLoc, ExprArg expr,Scope *CurScope) { |
| Expr *ThrowExpr = expr.takeAs<Expr>(); |
| if (!ThrowExpr) { |
| // @throw without an expression designates a rethrow (which much occur |
| // in the context of an @catch clause). |
| Scope *AtCatchParent = CurScope; |
| while (AtCatchParent && !AtCatchParent->isAtCatchScope()) |
| AtCatchParent = AtCatchParent->getParent(); |
| if (!AtCatchParent) |
| return StmtError(Diag(AtLoc, diag::error_rethrow_used_outside_catch)); |
| } else { |
| QualType ThrowType = ThrowExpr->getType(); |
| // Make sure the expression type is an ObjC pointer or "void *". |
| if (!ThrowType->isObjCObjectPointerType()) { |
| const PointerType *PT = ThrowType->getAs<PointerType>(); |
| if (!PT || !PT->getPointeeType()->isVoidType()) |
| return StmtError(Diag(AtLoc, diag::error_objc_throw_expects_object) |
| << ThrowExpr->getType() << ThrowExpr->getSourceRange()); |
| } |
| } |
| return Owned(new (Context) ObjCAtThrowStmt(AtLoc, ThrowExpr)); |
| } |
| |
| Action::OwningStmtResult |
| Sema::ActOnObjCAtSynchronizedStmt(SourceLocation AtLoc, ExprArg SynchExpr, |
| StmtArg SynchBody) { |
| CurFunctionNeedsScopeChecking = true; |
| |
| // Make sure the expression type is an ObjC pointer or "void *". |
| Expr *SyncExpr = static_cast<Expr*>(SynchExpr.get()); |
| if (!SyncExpr->getType()->isObjCObjectPointerType()) { |
| const PointerType *PT = SyncExpr->getType()->getAs<PointerType>(); |
| if (!PT || !PT->getPointeeType()->isVoidType()) |
| return StmtError(Diag(AtLoc, diag::error_objc_synchronized_expects_object) |
| << SyncExpr->getType() << SyncExpr->getSourceRange()); |
| } |
| |
| return Owned(new (Context) ObjCAtSynchronizedStmt(AtLoc, |
| SynchExpr.takeAs<Stmt>(), |
| SynchBody.takeAs<Stmt>())); |
| } |
| |
| /// ActOnCXXCatchBlock - Takes an exception declaration and a handler block |
| /// and creates a proper catch handler from them. |
| Action::OwningStmtResult |
| Sema::ActOnCXXCatchBlock(SourceLocation CatchLoc, DeclPtrTy ExDecl, |
| StmtArg HandlerBlock) { |
| // There's nothing to test that ActOnExceptionDecl didn't already test. |
| return Owned(new (Context) CXXCatchStmt(CatchLoc, |
| cast_or_null<VarDecl>(ExDecl.getAs<Decl>()), |
| HandlerBlock.takeAs<Stmt>())); |
| } |
| |
| class TypeWithHandler { |
| QualType t; |
| CXXCatchStmt *stmt; |
| public: |
| TypeWithHandler(const QualType &type, CXXCatchStmt *statement) |
| : t(type), stmt(statement) {} |
| |
| // An arbitrary order is fine as long as it places identical |
| // types next to each other. |
| bool operator<(const TypeWithHandler &y) const { |
| if (t.getAsOpaquePtr() < y.t.getAsOpaquePtr()) |
| return true; |
| if (t.getAsOpaquePtr() > y.t.getAsOpaquePtr()) |
| return false; |
| else |
| return getTypeSpecStartLoc() < y.getTypeSpecStartLoc(); |
| } |
| |
| bool operator==(const TypeWithHandler& other) const { |
| return t == other.t; |
| } |
| |
| QualType getQualType() const { return t; } |
| CXXCatchStmt *getCatchStmt() const { return stmt; } |
| SourceLocation getTypeSpecStartLoc() const { |
| return stmt->getExceptionDecl()->getTypeSpecStartLoc(); |
| } |
| }; |
| |
| /// ActOnCXXTryBlock - Takes a try compound-statement and a number of |
| /// handlers and creates a try statement from them. |
| Action::OwningStmtResult |
| Sema::ActOnCXXTryBlock(SourceLocation TryLoc, StmtArg TryBlock, |
| MultiStmtArg RawHandlers) { |
| unsigned NumHandlers = RawHandlers.size(); |
| assert(NumHandlers > 0 && |
| "The parser shouldn't call this if there are no handlers."); |
| Stmt **Handlers = reinterpret_cast<Stmt**>(RawHandlers.get()); |
| |
| llvm::SmallVector<TypeWithHandler, 8> TypesWithHandlers; |
| |
| for (unsigned i = 0; i < NumHandlers; ++i) { |
| CXXCatchStmt *Handler = llvm::cast<CXXCatchStmt>(Handlers[i]); |
| if (!Handler->getExceptionDecl()) { |
| if (i < NumHandlers - 1) |
| return StmtError(Diag(Handler->getLocStart(), |
| diag::err_early_catch_all)); |
| |
| continue; |
| } |
| |
| const QualType CaughtType = Handler->getCaughtType(); |
| const QualType CanonicalCaughtType = Context.getCanonicalType(CaughtType); |
| TypesWithHandlers.push_back(TypeWithHandler(CanonicalCaughtType, Handler)); |
| } |
| |
| // Detect handlers for the same type as an earlier one. |
| if (NumHandlers > 1) { |
| llvm::array_pod_sort(TypesWithHandlers.begin(), TypesWithHandlers.end()); |
| |
| TypeWithHandler prev = TypesWithHandlers[0]; |
| for (unsigned i = 1; i < TypesWithHandlers.size(); ++i) { |
| TypeWithHandler curr = TypesWithHandlers[i]; |
| |
| if (curr == prev) { |
| Diag(curr.getTypeSpecStartLoc(), |
| diag::warn_exception_caught_by_earlier_handler) |
| << curr.getCatchStmt()->getCaughtType().getAsString(); |
| Diag(prev.getTypeSpecStartLoc(), |
| diag::note_previous_exception_handler) |
| << prev.getCatchStmt()->getCaughtType().getAsString(); |
| } |
| |
| prev = curr; |
| } |
| } |
| |
| // FIXME: We should detect handlers that cannot catch anything because an |
| // earlier handler catches a superclass. Need to find a method that is not |
| // quadratic for this. |
| // Neither of these are explicitly forbidden, but every compiler detects them |
| // and warns. |
| |
| CurFunctionNeedsScopeChecking = true; |
| RawHandlers.release(); |
| return Owned(new (Context) CXXTryStmt(TryLoc, |
| static_cast<Stmt*>(TryBlock.release()), |
| Handlers, NumHandlers)); |
| } |