| //===--- 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 "clang/Sema/SemaInternal.h" |
| #include "clang/Sema/Scope.h" |
| #include "clang/Sema/ScopeInfo.h" |
| #include "clang/Sema/Initialization.h" |
| #include "clang/Sema/Lookup.h" |
| #include "clang/AST/ASTContext.h" |
| #include "clang/AST/CharUnits.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/AST/TypeLoc.h" |
| #include "clang/Lex/Preprocessor.h" |
| #include "clang/Basic/TargetInfo.h" |
| #include "llvm/ADT/ArrayRef.h" |
| #include "llvm/ADT/STLExtras.h" |
| #include "llvm/ADT/SmallVector.h" |
| using namespace clang; |
| using namespace sema; |
| |
| StmtResult Sema::ActOnExprStmt(FullExprArg expr) { |
| Expr *E = expr.get(); |
| if (!E) // FIXME: FullExprArg has no error state? |
| 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)); |
| } |
| |
| |
| StmtResult Sema::ActOnNullStmt(SourceLocation SemiLoc, |
| bool HasLeadingEmptyMacro) { |
| return Owned(new (Context) NullStmt(SemiLoc, HasLeadingEmptyMacro)); |
| } |
| |
| StmtResult 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; |
| VarDecl *var = cast<VarDecl>(DG.getSingleDecl()); |
| |
| // suppress any potential 'unused variable' warning. |
| var->setUsed(); |
| |
| // foreach variables are never actually initialized in the way that |
| // the parser came up with. |
| var->setInit(0); |
| |
| // In ARC, we don't need to retain the iteration variable of a fast |
| // enumeration loop. Rather than actually trying to catch that |
| // during declaration processing, we remove the consequences here. |
| if (getLangOptions().ObjCAutoRefCount) { |
| QualType type = var->getType(); |
| |
| // Only do this if we inferred the lifetime. Inferred lifetime |
| // will show up as a local qualifier because explicit lifetime |
| // should have shown up as an AttributedType instead. |
| if (type.getLocalQualifiers().getObjCLifetime() == Qualifiers::OCL_Strong) { |
| // Add 'const' and mark the variable as pseudo-strong. |
| var->setType(type.withConst()); |
| var->setARCPseudoStrong(true); |
| } |
| } |
| } |
| |
| /// \brief Diagnose unused '==' and '!=' as likely typos for '=' or '|='. |
| /// |
| /// Adding a cast to void (or other expression wrappers) will prevent the |
| /// warning from firing. |
| static bool DiagnoseUnusedComparison(Sema &S, const Expr *E) { |
| SourceLocation Loc; |
| bool IsNotEqual, CanAssign; |
| |
| if (const BinaryOperator *Op = dyn_cast<BinaryOperator>(E)) { |
| if (Op->getOpcode() != BO_EQ && Op->getOpcode() != BO_NE) |
| return false; |
| |
| Loc = Op->getOperatorLoc(); |
| IsNotEqual = Op->getOpcode() == BO_NE; |
| CanAssign = Op->getLHS()->IgnoreParenImpCasts()->isLValue(); |
| } else if (const CXXOperatorCallExpr *Op = dyn_cast<CXXOperatorCallExpr>(E)) { |
| if (Op->getOperator() != OO_EqualEqual && |
| Op->getOperator() != OO_ExclaimEqual) |
| return false; |
| |
| Loc = Op->getOperatorLoc(); |
| IsNotEqual = Op->getOperator() == OO_ExclaimEqual; |
| CanAssign = Op->getArg(0)->IgnoreParenImpCasts()->isLValue(); |
| } else { |
| // Not a typo-prone comparison. |
| return false; |
| } |
| |
| // Suppress warnings when the operator, suspicious as it may be, comes from |
| // a macro expansion. |
| if (Loc.isMacroID()) |
| return false; |
| |
| S.Diag(Loc, diag::warn_unused_comparison) |
| << (unsigned)IsNotEqual << E->getSourceRange(); |
| |
| // If the LHS is a plausible entity to assign to, provide a fixit hint to |
| // correct common typos. |
| if (CanAssign) { |
| if (IsNotEqual) |
| S.Diag(Loc, diag::note_inequality_comparison_to_or_assign) |
| << FixItHint::CreateReplacement(Loc, "|="); |
| else |
| S.Diag(Loc, diag::note_equality_comparison_to_assign) |
| << FixItHint::CreateReplacement(Loc, "="); |
| } |
| |
| return true; |
| } |
| |
| void Sema::DiagnoseUnusedExprResult(const Stmt *S) { |
| if (const LabelStmt *Label = dyn_cast_or_null<LabelStmt>(S)) |
| return DiagnoseUnusedExprResult(Label->getSubStmt()); |
| |
| const Expr *E = dyn_cast_or_null<Expr>(S); |
| if (!E) |
| return; |
| |
| SourceLocation Loc; |
| SourceRange R1, R2; |
| if (SourceMgr.isInSystemMacro(E->getExprLoc()) || |
| !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; |
| if (const ExprWithCleanups *Temps = dyn_cast<ExprWithCleanups>(E)) |
| E = Temps->getSubExpr(); |
| if (const CXXBindTemporaryExpr *TempExpr = dyn_cast<CXXBindTemporaryExpr>(E)) |
| E = TempExpr->getSubExpr(); |
| |
| if (DiagnoseUnusedComparison(*this, E)) |
| return; |
| |
| E = E->IgnoreParenImpCasts(); |
| if (const CallExpr *CE = dyn_cast<CallExpr>(E)) { |
| if (E->getType()->isVoidType()) |
| return; |
| |
| // 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_result) << R1 << R2; |
| 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; |
| } |
| } |
| } else if (const ObjCMessageExpr *ME = dyn_cast<ObjCMessageExpr>(E)) { |
| if (getLangOptions().ObjCAutoRefCount && ME->isDelegateInitCall()) { |
| Diag(Loc, diag::err_arc_unused_init_message) << R1; |
| return; |
| } |
| const ObjCMethodDecl *MD = ME->getMethodDecl(); |
| if (MD && MD->getAttr<WarnUnusedResultAttr>()) { |
| Diag(Loc, diag::warn_unused_result) << R1 << R2; |
| return; |
| } |
| } else if (isa<PseudoObjectExpr>(E)) { |
| DiagID = diag::warn_unused_property_expr; |
| } else if (const CXXFunctionalCastExpr *FC |
| = dyn_cast<CXXFunctionalCastExpr>(E)) { |
| if (isa<CXXConstructExpr>(FC->getSubExpr()) || |
| isa<CXXTemporaryObjectExpr>(FC->getSubExpr())) |
| return; |
| } |
| // Diagnose "(void*) blah" as a typo for "(void) blah". |
| else if (const CStyleCastExpr *CE = dyn_cast<CStyleCastExpr>(E)) { |
| TypeSourceInfo *TI = CE->getTypeInfoAsWritten(); |
| QualType T = TI->getType(); |
| |
| // We really do want to use the non-canonical type here. |
| if (T == Context.VoidPtrTy) { |
| PointerTypeLoc TL = cast<PointerTypeLoc>(TI->getTypeLoc()); |
| |
| Diag(Loc, diag::warn_unused_voidptr) |
| << FixItHint::CreateRemoval(TL.getStarLoc()); |
| return; |
| } |
| } |
| |
| DiagRuntimeBehavior(Loc, 0, PDiag(DiagID) << R1 << R2); |
| } |
| |
| StmtResult |
| 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)); |
| } |
| |
| StmtResult |
| Sema::ActOnCaseStmt(SourceLocation CaseLoc, Expr *LHSVal, |
| SourceLocation DotDotDotLoc, Expr *RHSVal, |
| SourceLocation ColonLoc) { |
| assert((LHSVal != 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. |
| if (!LHSVal->isTypeDependent() && !LHSVal->isValueDependent() && |
| VerifyIntegerConstantExpression(LHSVal)) |
| return StmtError(); |
| |
| // GCC extension: The expression shall be an integer constant. |
| |
| if (RHSVal && !RHSVal->isTypeDependent() && !RHSVal->isValueDependent() && |
| VerifyIntegerConstantExpression(RHSVal)) { |
| RHSVal = 0; // Recover by just forgetting about it. |
| } |
| |
| if (getCurFunction()->SwitchStack.empty()) { |
| Diag(CaseLoc, diag::err_case_not_in_switch); |
| return StmtError(); |
| } |
| |
| CaseStmt *CS = new (Context) CaseStmt(LHSVal, RHSVal, CaseLoc, DotDotDotLoc, |
| ColonLoc); |
| getCurFunction()->SwitchStack.back()->addSwitchCase(CS); |
| return Owned(CS); |
| } |
| |
| /// ActOnCaseStmtBody - This installs a statement as the body of a case. |
| void Sema::ActOnCaseStmtBody(Stmt *caseStmt, Stmt *SubStmt) { |
| DiagnoseUnusedExprResult(SubStmt); |
| |
| CaseStmt *CS = static_cast<CaseStmt*>(caseStmt); |
| CS->setSubStmt(SubStmt); |
| } |
| |
| StmtResult |
| Sema::ActOnDefaultStmt(SourceLocation DefaultLoc, SourceLocation ColonLoc, |
| Stmt *SubStmt, Scope *CurScope) { |
| DiagnoseUnusedExprResult(SubStmt); |
| |
| if (getCurFunction()->SwitchStack.empty()) { |
| Diag(DefaultLoc, diag::err_default_not_in_switch); |
| return Owned(SubStmt); |
| } |
| |
| DefaultStmt *DS = new (Context) DefaultStmt(DefaultLoc, ColonLoc, SubStmt); |
| getCurFunction()->SwitchStack.back()->addSwitchCase(DS); |
| return Owned(DS); |
| } |
| |
| StmtResult |
| Sema::ActOnLabelStmt(SourceLocation IdentLoc, LabelDecl *TheDecl, |
| SourceLocation ColonLoc, Stmt *SubStmt) { |
| |
| // If the label was multiply defined, reject it now. |
| if (TheDecl->getStmt()) { |
| Diag(IdentLoc, diag::err_redefinition_of_label) << TheDecl->getDeclName(); |
| Diag(TheDecl->getLocation(), diag::note_previous_definition); |
| return Owned(SubStmt); |
| } |
| |
| // Otherwise, things are good. Fill in the declaration and return it. |
| LabelStmt *LS = new (Context) LabelStmt(IdentLoc, TheDecl, SubStmt); |
| TheDecl->setStmt(LS); |
| if (!TheDecl->isGnuLocal()) |
| TheDecl->setLocation(IdentLoc); |
| return Owned(LS); |
| } |
| |
| StmtResult |
| Sema::ActOnIfStmt(SourceLocation IfLoc, FullExprArg CondVal, Decl *CondVar, |
| Stmt *thenStmt, SourceLocation ElseLoc, |
| Stmt *elseStmt) { |
| ExprResult CondResult(CondVal.release()); |
| |
| VarDecl *ConditionVar = 0; |
| if (CondVar) { |
| ConditionVar = cast<VarDecl>(CondVar); |
| CondResult = CheckConditionVariable(ConditionVar, IfLoc, true); |
| if (CondResult.isInvalid()) |
| return StmtError(); |
| } |
| Expr *ConditionExpr = CondResult.takeAs<Expr>(); |
| if (!ConditionExpr) |
| return StmtError(); |
| |
| 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 (!elseStmt) { |
| if (NullStmt* stmt = dyn_cast<NullStmt>(thenStmt)) |
| // But do not warn if the body is a macro that expands to nothing, e.g: |
| // |
| // #define CALL(x) |
| // if (condition) |
| // CALL(0); |
| // |
| if (!stmt->hasLeadingEmptyMacro()) |
| Diag(stmt->getSemiLoc(), diag::warn_empty_if_body); |
| } |
| |
| DiagnoseUnusedExprResult(elseStmt); |
| |
| return Owned(new (Context) IfStmt(Context, IfLoc, ConditionVar, ConditionExpr, |
| thenStmt, ElseLoc, elseStmt)); |
| } |
| |
| /// 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. |
| Val = Val.extend(NewWidth); |
| Val.setIsSigned(NewSign); |
| |
| // If the input was signed and negative and the output is |
| // unsigned, don't bother to warn: this is implementation-defined |
| // behavior. |
| // FIXME: Introduce a second, default-ignored warning for this case? |
| } else if (NewWidth < Val.getBitWidth()) { |
| // If this is a truncation, check for overflow. |
| llvm::APSInt ConvVal(Val); |
| ConvVal = ConvVal.trunc(NewWidth); |
| ConvVal.setIsSigned(NewSign); |
| ConvVal = 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 = 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) |
| // We don't diagnose this overflow, because it is implementation-defined |
| // behavior. |
| // FIXME: Introduce a second, default-ignored warning for this case? |
| llvm::APSInt OldVal(Val); |
| Val.setIsSigned(NewSign); |
| } |
| } |
| |
| 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; |
| } |
| |
| /// CmpEnumVals - Comparison predicate for sorting enumeration values. |
| /// |
| static bool CmpEnumVals(const std::pair<llvm::APSInt, EnumConstantDecl*>& lhs, |
| const std::pair<llvm::APSInt, EnumConstantDecl*>& rhs) |
| { |
| return lhs.first < rhs.first; |
| } |
| |
| /// EqEnumVals - Comparison preficate for uniqing enumeration values. |
| /// |
| static bool EqEnumVals(const std::pair<llvm::APSInt, EnumConstantDecl*>& lhs, |
| const std::pair<llvm::APSInt, EnumConstantDecl*>& rhs) |
| { |
| return lhs.first == rhs.first; |
| } |
| |
| /// GetTypeBeforeIntegralPromotion - Returns the pre-promotion type of |
| /// potentially integral-promoted expression @p expr. |
| static QualType GetTypeBeforeIntegralPromotion(Expr *&expr) { |
| if (ExprWithCleanups *cleanups = dyn_cast<ExprWithCleanups>(expr)) |
| expr = cleanups->getSubExpr(); |
| while (ImplicitCastExpr *impcast = dyn_cast<ImplicitCastExpr>(expr)) { |
| if (impcast->getCastKind() != CK_IntegralCast) break; |
| expr = impcast->getSubExpr(); |
| } |
| return expr->getType(); |
| } |
| |
| StmtResult |
| Sema::ActOnStartOfSwitchStmt(SourceLocation SwitchLoc, Expr *Cond, |
| Decl *CondVar) { |
| ExprResult CondResult; |
| |
| VarDecl *ConditionVar = 0; |
| if (CondVar) { |
| ConditionVar = cast<VarDecl>(CondVar); |
| CondResult = CheckConditionVariable(ConditionVar, SourceLocation(), false); |
| if (CondResult.isInvalid()) |
| return StmtError(); |
| |
| Cond = CondResult.release(); |
| } |
| |
| if (!Cond) |
| return StmtError(); |
| |
| CondResult = CheckPlaceholderExpr(Cond); |
| if (CondResult.isInvalid()) |
| return StmtError(); |
| |
| CondResult |
| = ConvertToIntegralOrEnumerationType(SwitchLoc, CondResult.take(), |
| PDiag(diag::err_typecheck_statement_requires_integer), |
| PDiag(diag::err_switch_incomplete_class_type) |
| << Cond->getSourceRange(), |
| PDiag(diag::err_switch_explicit_conversion), |
| PDiag(diag::note_switch_conversion), |
| PDiag(diag::err_switch_multiple_conversions), |
| PDiag(diag::note_switch_conversion), |
| PDiag(0)); |
| if (CondResult.isInvalid()) return StmtError(); |
| Cond = CondResult.take(); |
| |
| // C99 6.8.4.2p5 - Integer promotions are performed on the controlling expr. |
| CondResult = UsualUnaryConversions(Cond); |
| if (CondResult.isInvalid()) return StmtError(); |
| Cond = CondResult.take(); |
| |
| if (!CondVar) { |
| CheckImplicitConversions(Cond, SwitchLoc); |
| CondResult = MaybeCreateExprWithCleanups(Cond); |
| if (CondResult.isInvalid()) |
| return StmtError(); |
| Cond = CondResult.take(); |
| } |
| |
| getCurFunction()->setHasBranchIntoScope(); |
| |
| SwitchStmt *SS = new (Context) SwitchStmt(Context, ConditionVar, Cond); |
| getCurFunction()->SwitchStack.push_back(SS); |
| return Owned(SS); |
| } |
| |
| static void AdjustAPSInt(llvm::APSInt &Val, unsigned BitWidth, bool IsSigned) { |
| if (Val.getBitWidth() < BitWidth) |
| Val = Val.extend(BitWidth); |
| else if (Val.getBitWidth() > BitWidth) |
| Val = Val.trunc(BitWidth); |
| Val.setIsSigned(IsSigned); |
| } |
| |
| StmtResult |
| Sema::ActOnFinishSwitchStmt(SourceLocation SwitchLoc, Stmt *Switch, |
| Stmt *BodyStmt) { |
| SwitchStmt *SS = cast<SwitchStmt>(Switch); |
| assert(SS == getCurFunction()->SwitchStack.back() && |
| "switch stack missing push/pop!"); |
| |
| SS->setBody(BodyStmt, SwitchLoc); |
| getCurFunction()->SwitchStack.pop_back(); |
| |
| Expr *CondExpr = SS->getCond(); |
| if (!CondExpr) return StmtError(); |
| |
| QualType CondType = CondExpr->getType(); |
| |
| Expr *CondExprBeforePromotion = CondExpr; |
| QualType CondTypeBeforePromotion = |
| GetTypeBeforeIntegralPromotion(CondExprBeforePromotion); |
| |
| // 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()) { |
| // We have already converted the expression to an integral or enumeration |
| // type, when we started the switch statement. If we don't have an |
| // appropriate type now, just return an error. |
| if (!CondType->isIntegralOrEnumerationType()) |
| return StmtError(); |
| |
| if (CondExpr->isKnownToHaveBooleanValue()) { |
| // 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 : Context.getIntWidth(CondTypeBeforePromotion); |
| bool CondIsSigned |
| = CondTypeBeforePromotion->isSignedIntegerOrEnumerationType(); |
| |
| // 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 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. |
| typedef std::vector<std::pair<llvm::APSInt, CaseStmt*> > CaseRangesTy; |
| CaseRangesTy 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->EvaluateKnownConstInt(Context); |
| |
| // Convert the value to the same width/sign as the condition. |
| ConvertIntegerToTypeWarnOnOverflow(LoVal, CondWidth, CondIsSigned, |
| Lo->getLocStart(), |
| diag::warn_case_value_overflow); |
| |
| // If the LHS is not the same type as the condition, insert an implicit |
| // cast. |
| // FIXME: In C++11, the value is a converted constant expression of the |
| // promoted type of the switch condition. |
| Lo = DefaultLvalueConversion(Lo).take(); |
| Lo = ImpCastExprToType(Lo, CondType, CK_IntegralCast).take(); |
| 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) { |
| // If we don't have a default statement, check whether the |
| // condition is constant. |
| llvm::APSInt ConstantCondValue; |
| bool HasConstantCond = false; |
| if (!HasDependentValue && !TheDefaultStmt) { |
| HasConstantCond |
| = CondExprBeforePromotion->EvaluateAsInt(ConstantCondValue, Context, |
| Expr::SE_AllowSideEffects); |
| assert(!HasConstantCond || |
| (ConstantCondValue.getBitWidth() == CondWidth && |
| ConstantCondValue.isSigned() == CondIsSigned)); |
| } |
| bool ShouldCheckConstantCond = HasConstantCond; |
| |
| // 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(); i != e; ++i) { |
| if (ShouldCheckConstantCond && |
| CaseVals[i].first == ConstantCondValue) |
| ShouldCheckConstantCond = false; |
| |
| if (i != 0 && CaseVals[i].first == CaseVals[i-1].first) { |
| // If we have a duplicate, report it. |
| Diag(CaseVals[i].second->getLHS()->getLocStart(), |
| diag::err_duplicate_case) << CaseVals[i].first.toString(10); |
| Diag(CaseVals[i-1].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) { |
| llvm::APSInt &LoVal = CaseRanges[i].first; |
| CaseStmt *CR = CaseRanges[i].second; |
| Expr *Hi = CR->getRHS(); |
| llvm::APSInt HiVal = Hi->EvaluateKnownConstInt(Context); |
| |
| // Convert the value to the same width/sign as the condition. |
| ConvertIntegerToTypeWarnOnOverflow(HiVal, CondWidth, CondIsSigned, |
| Hi->getLocStart(), |
| diag::warn_case_value_overflow); |
| |
| // If the RHS is not the same type as the condition, insert an implicit |
| // cast. |
| // FIXME: In C++11, the value is a converted constant expression of the |
| // promoted type of the switch condition. |
| Hi = DefaultLvalueConversion(Hi).take(); |
| Hi = ImpCastExprToType(Hi, CondType, CK_IntegralCast).take(); |
| CR->setRHS(Hi); |
| |
| // If the low value is bigger than the high value, the case is empty. |
| if (LoVal > HiVal) { |
| Diag(CR->getLHS()->getLocStart(), diag::warn_case_empty_range) |
| << SourceRange(CR->getLHS()->getLocStart(), |
| Hi->getLocEnd()); |
| CaseRanges.erase(CaseRanges.begin()+i); |
| --i, --e; |
| continue; |
| } |
| |
| if (ShouldCheckConstantCond && |
| LoVal <= ConstantCondValue && |
| ConstantCondValue <= HiVal) |
| ShouldCheckConstantCond = false; |
| |
| 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; |
| } |
| } |
| } |
| |
| // Complain if we have a constant condition and we didn't find a match. |
| if (!CaseListIsErroneous && ShouldCheckConstantCond) { |
| // TODO: it would be nice if we printed enums as enums, chars as |
| // chars, etc. |
| Diag(CondExpr->getExprLoc(), diag::warn_missing_case_for_condition) |
| << ConstantCondValue.toString(10) |
| << CondExpr->getSourceRange(); |
| } |
| |
| // Check to see if switch is over an Enum and handles all of its |
| // values. We only issue a warning if there is not 'default:', but |
| // we still do the analysis to preserve this information in the AST |
| // (which can be used by flow-based analyes). |
| // |
| const EnumType *ET = CondTypeBeforePromotion->getAs<EnumType>(); |
| |
| // If switch has default case, then ignore it. |
| if (!CaseListIsErroneous && !HasConstantCond && ET) { |
| const EnumDecl *ED = ET->getDecl(); |
| typedef SmallVector<std::pair<llvm::APSInt, EnumConstantDecl*>, 64> |
| EnumValsTy; |
| EnumValsTy EnumVals; |
| |
| // Gather all enum values, set their type and sort them, |
| // allowing easier comparison with CaseVals. |
| for (EnumDecl::enumerator_iterator EDI = ED->enumerator_begin(); |
| EDI != ED->enumerator_end(); ++EDI) { |
| llvm::APSInt Val = EDI->getInitVal(); |
| AdjustAPSInt(Val, CondWidth, CondIsSigned); |
| EnumVals.push_back(std::make_pair(Val, *EDI)); |
| } |
| std::stable_sort(EnumVals.begin(), EnumVals.end(), CmpEnumVals); |
| EnumValsTy::iterator EIend = |
| std::unique(EnumVals.begin(), EnumVals.end(), EqEnumVals); |
| |
| // See which case values aren't in enum. |
| // TODO: we might want to check whether case values are out of the |
| // enum even if we don't want to check whether all cases are handled. |
| if (!TheDefaultStmt) { |
| EnumValsTy::const_iterator EI = EnumVals.begin(); |
| for (CaseValsTy::const_iterator CI = CaseVals.begin(); |
| CI != CaseVals.end(); CI++) { |
| while (EI != EIend && EI->first < CI->first) |
| EI++; |
| if (EI == EIend || EI->first > CI->first) |
| Diag(CI->second->getLHS()->getExprLoc(), diag::warn_not_in_enum) |
| << ED->getDeclName(); |
| } |
| // See which of case ranges aren't in enum |
| EI = EnumVals.begin(); |
| for (CaseRangesTy::const_iterator RI = CaseRanges.begin(); |
| RI != CaseRanges.end() && EI != EIend; RI++) { |
| while (EI != EIend && EI->first < RI->first) |
| EI++; |
| |
| if (EI == EIend || EI->first != RI->first) { |
| Diag(RI->second->getLHS()->getExprLoc(), diag::warn_not_in_enum) |
| << ED->getDeclName(); |
| } |
| |
| llvm::APSInt Hi = |
| RI->second->getRHS()->EvaluateKnownConstInt(Context); |
| AdjustAPSInt(Hi, CondWidth, CondIsSigned); |
| while (EI != EIend && EI->first < Hi) |
| EI++; |
| if (EI == EIend || EI->first != Hi) |
| Diag(RI->second->getRHS()->getExprLoc(), diag::warn_not_in_enum) |
| << ED->getDeclName(); |
| } |
| } |
| |
| // Check which enum vals aren't in switch |
| CaseValsTy::const_iterator CI = CaseVals.begin(); |
| CaseRangesTy::const_iterator RI = CaseRanges.begin(); |
| bool hasCasesNotInSwitch = false; |
| |
| SmallVector<DeclarationName,8> UnhandledNames; |
| |
| for (EnumValsTy::const_iterator EI = EnumVals.begin(); EI != EIend; EI++){ |
| // Drop unneeded case values |
| llvm::APSInt CIVal; |
| while (CI != CaseVals.end() && CI->first < EI->first) |
| CI++; |
| |
| if (CI != CaseVals.end() && CI->first == EI->first) |
| continue; |
| |
| // Drop unneeded case ranges |
| for (; RI != CaseRanges.end(); RI++) { |
| llvm::APSInt Hi = |
| RI->second->getRHS()->EvaluateKnownConstInt(Context); |
| AdjustAPSInt(Hi, CondWidth, CondIsSigned); |
| if (EI->first <= Hi) |
| break; |
| } |
| |
| if (RI == CaseRanges.end() || EI->first < RI->first) { |
| hasCasesNotInSwitch = true; |
| if (!TheDefaultStmt) |
| UnhandledNames.push_back(EI->second->getDeclName()); |
| } |
| } |
| |
| // Produce a nice diagnostic if multiple values aren't handled. |
| switch (UnhandledNames.size()) { |
| case 0: break; |
| case 1: |
| Diag(CondExpr->getExprLoc(), diag::warn_missing_case1) |
| << UnhandledNames[0]; |
| break; |
| case 2: |
| Diag(CondExpr->getExprLoc(), diag::warn_missing_case2) |
| << UnhandledNames[0] << UnhandledNames[1]; |
| break; |
| case 3: |
| Diag(CondExpr->getExprLoc(), diag::warn_missing_case3) |
| << UnhandledNames[0] << UnhandledNames[1] << UnhandledNames[2]; |
| break; |
| default: |
| Diag(CondExpr->getExprLoc(), diag::warn_missing_cases) |
| << (unsigned)UnhandledNames.size() |
| << UnhandledNames[0] << UnhandledNames[1] << UnhandledNames[2]; |
| break; |
| } |
| |
| if (!hasCasesNotInSwitch) |
| SS->setAllEnumCasesCovered(); |
| } |
| } |
| |
| // 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(); |
| |
| return Owned(SS); |
| } |
| |
| StmtResult |
| Sema::ActOnWhileStmt(SourceLocation WhileLoc, FullExprArg Cond, |
| Decl *CondVar, Stmt *Body) { |
| ExprResult CondResult(Cond.release()); |
| |
| VarDecl *ConditionVar = 0; |
| if (CondVar) { |
| ConditionVar = cast<VarDecl>(CondVar); |
| CondResult = CheckConditionVariable(ConditionVar, WhileLoc, true); |
| if (CondResult.isInvalid()) |
| return StmtError(); |
| } |
| Expr *ConditionExpr = CondResult.take(); |
| if (!ConditionExpr) |
| return StmtError(); |
| |
| DiagnoseUnusedExprResult(Body); |
| |
| return Owned(new (Context) WhileStmt(Context, ConditionVar, ConditionExpr, |
| Body, WhileLoc)); |
| } |
| |
| StmtResult |
| Sema::ActOnDoStmt(SourceLocation DoLoc, Stmt *Body, |
| SourceLocation WhileLoc, SourceLocation CondLParen, |
| Expr *Cond, SourceLocation CondRParen) { |
| assert(Cond && "ActOnDoStmt(): missing expression"); |
| |
| ExprResult CondResult = CheckBooleanCondition(Cond, DoLoc); |
| if (CondResult.isInvalid() || CondResult.isInvalid()) |
| return StmtError(); |
| Cond = CondResult.take(); |
| |
| CheckImplicitConversions(Cond, DoLoc); |
| CondResult = MaybeCreateExprWithCleanups(Cond); |
| if (CondResult.isInvalid()) |
| return StmtError(); |
| Cond = CondResult.take(); |
| |
| DiagnoseUnusedExprResult(Body); |
| |
| return Owned(new (Context) DoStmt(Body, Cond, DoLoc, WhileLoc, CondRParen)); |
| } |
| |
| StmtResult |
| Sema::ActOnForStmt(SourceLocation ForLoc, SourceLocation LParenLoc, |
| Stmt *First, FullExprArg second, Decl *secondVar, |
| FullExprArg third, |
| SourceLocation RParenLoc, Stmt *Body) { |
| 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->isLocalVarDecl() && !VD->hasLocalStorage()) |
| VD = 0; |
| if (VD == 0) |
| Diag((*DI)->getLocation(), diag::err_non_variable_decl_in_for); |
| // FIXME: mark decl erroneous! |
| } |
| } |
| } |
| |
| ExprResult SecondResult(second.release()); |
| VarDecl *ConditionVar = 0; |
| if (secondVar) { |
| ConditionVar = cast<VarDecl>(secondVar); |
| SecondResult = CheckConditionVariable(ConditionVar, ForLoc, true); |
| if (SecondResult.isInvalid()) |
| return StmtError(); |
| } |
| |
| Expr *Third = third.release().takeAs<Expr>(); |
| |
| DiagnoseUnusedExprResult(First); |
| DiagnoseUnusedExprResult(Third); |
| DiagnoseUnusedExprResult(Body); |
| |
| return Owned(new (Context) ForStmt(Context, First, |
| SecondResult.take(), ConditionVar, |
| Third, Body, ForLoc, LParenLoc, |
| RParenLoc)); |
| } |
| |
| /// In an Objective C collection iteration statement: |
| /// for (x in y) |
| /// x can be an arbitrary l-value expression. Bind it up as a |
| /// full-expression. |
| StmtResult Sema::ActOnForEachLValueExpr(Expr *E) { |
| CheckImplicitConversions(E); |
| ExprResult Result = MaybeCreateExprWithCleanups(E); |
| if (Result.isInvalid()) return StmtError(); |
| return Owned(static_cast<Stmt*>(Result.get())); |
| } |
| |
| ExprResult |
| Sema::ActOnObjCForCollectionOperand(SourceLocation forLoc, Expr *collection) { |
| assert(collection); |
| |
| // Bail out early if we've got a type-dependent expression. |
| if (collection->isTypeDependent()) return Owned(collection); |
| |
| // Perform normal l-value conversion. |
| ExprResult result = DefaultFunctionArrayLvalueConversion(collection); |
| if (result.isInvalid()) |
| return ExprError(); |
| collection = result.take(); |
| |
| // The operand needs to have object-pointer type. |
| // TODO: should we do a contextual conversion? |
| const ObjCObjectPointerType *pointerType = |
| collection->getType()->getAs<ObjCObjectPointerType>(); |
| if (!pointerType) |
| return Diag(forLoc, diag::err_collection_expr_type) |
| << collection->getType() << collection->getSourceRange(); |
| |
| // Check that the operand provides |
| // - countByEnumeratingWithState:objects:count: |
| const ObjCObjectType *objectType = pointerType->getObjectType(); |
| ObjCInterfaceDecl *iface = objectType->getInterface(); |
| |
| // If we have a forward-declared type, we can't do this check. |
| // Under ARC, it is an error not to have a forward-declared class. |
| if (iface && |
| RequireCompleteType(forLoc, QualType(objectType, 0), |
| getLangOptions().ObjCAutoRefCount |
| ? PDiag(diag::err_arc_collection_forward) |
| << collection->getSourceRange() |
| : PDiag(0))) { |
| // Otherwise, if we have any useful type information, check that |
| // the type declares the appropriate method. |
| } else if (iface || !objectType->qual_empty()) { |
| IdentifierInfo *selectorIdents[] = { |
| &Context.Idents.get("countByEnumeratingWithState"), |
| &Context.Idents.get("objects"), |
| &Context.Idents.get("count") |
| }; |
| Selector selector = Context.Selectors.getSelector(3, &selectorIdents[0]); |
| |
| ObjCMethodDecl *method = 0; |
| |
| // If there's an interface, look in both the public and private APIs. |
| if (iface) { |
| method = iface->lookupInstanceMethod(selector); |
| if (!method) method = LookupPrivateInstanceMethod(selector, iface); |
| } |
| |
| // Also check protocol qualifiers. |
| if (!method) |
| method = LookupMethodInQualifiedType(selector, pointerType, |
| /*instance*/ true); |
| |
| // If we didn't find it anywhere, give up. |
| if (!method) { |
| Diag(forLoc, diag::warn_collection_expr_type) |
| << collection->getType() << selector << collection->getSourceRange(); |
| } |
| |
| // TODO: check for an incompatible signature? |
| } |
| |
| // Wrap up any cleanups in the expression. |
| return Owned(MaybeCreateExprWithCleanups(collection)); |
| } |
| |
| StmtResult |
| Sema::ActOnObjCForCollectionStmt(SourceLocation ForLoc, |
| SourceLocation LParenLoc, |
| Stmt *First, Expr *Second, |
| SourceLocation RParenLoc, Stmt *Body) { |
| 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)); |
| |
| VarDecl *D = cast<VarDecl>(DS->getSingleDecl()); |
| FirstType = 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'. |
| if (!D->hasLocalStorage()) |
| return StmtError(Diag(D->getLocation(), |
| diag::err_non_variable_decl_in_for)); |
| } else { |
| Expr *FirstE = cast<Expr>(First); |
| if (!FirstE->isTypeDependent() && !FirstE->isLValue()) |
| return StmtError(Diag(First->getLocStart(), |
| diag::err_selector_element_not_lvalue) |
| << First->getSourceRange()); |
| |
| FirstType = static_cast<Expr*>(First)->getType(); |
| } |
| if (!FirstType->isDependentType() && |
| !FirstType->isObjCObjectPointerType() && |
| !FirstType->isBlockPointerType()) |
| Diag(ForLoc, diag::err_selector_element_type) |
| << FirstType << First->getSourceRange(); |
| } |
| |
| return Owned(new (Context) ObjCForCollectionStmt(First, Second, Body, |
| ForLoc, RParenLoc)); |
| } |
| |
| namespace { |
| |
| enum BeginEndFunction { |
| BEF_begin, |
| BEF_end |
| }; |
| |
| /// Build a variable declaration for a for-range statement. |
| static VarDecl *BuildForRangeVarDecl(Sema &SemaRef, SourceLocation Loc, |
| QualType Type, const char *Name) { |
| DeclContext *DC = SemaRef.CurContext; |
| IdentifierInfo *II = &SemaRef.PP.getIdentifierTable().get(Name); |
| TypeSourceInfo *TInfo = SemaRef.Context.getTrivialTypeSourceInfo(Type, Loc); |
| VarDecl *Decl = VarDecl::Create(SemaRef.Context, DC, Loc, Loc, II, Type, |
| TInfo, SC_Auto, SC_None); |
| Decl->setImplicit(); |
| return Decl; |
| } |
| |
| /// Finish building a variable declaration for a for-range statement. |
| /// \return true if an error occurs. |
| static bool FinishForRangeVarDecl(Sema &SemaRef, VarDecl *Decl, Expr *Init, |
| SourceLocation Loc, int diag) { |
| // Deduce the type for the iterator variable now rather than leaving it to |
| // AddInitializerToDecl, so we can produce a more suitable diagnostic. |
| TypeSourceInfo *InitTSI = 0; |
| if (Init->getType()->isVoidType() || |
| !SemaRef.DeduceAutoType(Decl->getTypeSourceInfo(), Init, InitTSI)) |
| SemaRef.Diag(Loc, diag) << Init->getType(); |
| if (!InitTSI) { |
| Decl->setInvalidDecl(); |
| return true; |
| } |
| Decl->setTypeSourceInfo(InitTSI); |
| Decl->setType(InitTSI->getType()); |
| |
| // In ARC, infer lifetime. |
| // FIXME: ARC may want to turn this into 'const __unsafe_unretained' if |
| // we're doing the equivalent of fast iteration. |
| if (SemaRef.getLangOptions().ObjCAutoRefCount && |
| SemaRef.inferObjCARCLifetime(Decl)) |
| Decl->setInvalidDecl(); |
| |
| SemaRef.AddInitializerToDecl(Decl, Init, /*DirectInit=*/false, |
| /*TypeMayContainAuto=*/false); |
| SemaRef.FinalizeDeclaration(Decl); |
| SemaRef.CurContext->addHiddenDecl(Decl); |
| return false; |
| } |
| |
| /// Produce a note indicating which begin/end function was implicitly called |
| /// by a C++0x for-range statement. This is often not obvious from the code, |
| /// nor from the diagnostics produced when analysing the implicit expressions |
| /// required in a for-range statement. |
| void NoteForRangeBeginEndFunction(Sema &SemaRef, Expr *E, |
| BeginEndFunction BEF) { |
| CallExpr *CE = dyn_cast<CallExpr>(E); |
| if (!CE) |
| return; |
| FunctionDecl *D = dyn_cast<FunctionDecl>(CE->getCalleeDecl()); |
| if (!D) |
| return; |
| SourceLocation Loc = D->getLocation(); |
| |
| std::string Description; |
| bool IsTemplate = false; |
| if (FunctionTemplateDecl *FunTmpl = D->getPrimaryTemplate()) { |
| Description = SemaRef.getTemplateArgumentBindingsText( |
| FunTmpl->getTemplateParameters(), *D->getTemplateSpecializationArgs()); |
| IsTemplate = true; |
| } |
| |
| SemaRef.Diag(Loc, diag::note_for_range_begin_end) |
| << BEF << IsTemplate << Description << E->getType(); |
| } |
| |
| /// Build a call to 'begin' or 'end' for a C++0x for-range statement. If the |
| /// given LookupResult is non-empty, it is assumed to describe a member which |
| /// will be invoked. Otherwise, the function will be found via argument |
| /// dependent lookup. |
| static ExprResult BuildForRangeBeginEndCall(Sema &SemaRef, Scope *S, |
| SourceLocation Loc, |
| VarDecl *Decl, |
| BeginEndFunction BEF, |
| const DeclarationNameInfo &NameInfo, |
| LookupResult &MemberLookup, |
| Expr *Range) { |
| ExprResult CallExpr; |
| if (!MemberLookup.empty()) { |
| ExprResult MemberRef = |
| SemaRef.BuildMemberReferenceExpr(Range, Range->getType(), Loc, |
| /*IsPtr=*/false, CXXScopeSpec(), |
| /*Qualifier=*/0, MemberLookup, |
| /*TemplateArgs=*/0); |
| if (MemberRef.isInvalid()) |
| return ExprError(); |
| CallExpr = SemaRef.ActOnCallExpr(S, MemberRef.get(), Loc, MultiExprArg(), |
| Loc, 0); |
| if (CallExpr.isInvalid()) |
| return ExprError(); |
| } else { |
| UnresolvedSet<0> FoundNames; |
| // C++0x [stmt.ranged]p1: For the purposes of this name lookup, namespace |
| // std is an associated namespace. |
| UnresolvedLookupExpr *Fn = |
| UnresolvedLookupExpr::Create(SemaRef.Context, /*NamingClass=*/0, |
| NestedNameSpecifierLoc(), NameInfo, |
| /*NeedsADL=*/true, /*Overloaded=*/false, |
| FoundNames.begin(), FoundNames.end(), |
| /*LookInStdNamespace=*/true); |
| CallExpr = SemaRef.BuildOverloadedCallExpr(S, Fn, Fn, Loc, &Range, 1, Loc, |
| 0); |
| if (CallExpr.isInvalid()) { |
| SemaRef.Diag(Range->getLocStart(), diag::note_for_range_type) |
| << Range->getType(); |
| return ExprError(); |
| } |
| } |
| if (FinishForRangeVarDecl(SemaRef, Decl, CallExpr.get(), Loc, |
| diag::err_for_range_iter_deduction_failure)) { |
| NoteForRangeBeginEndFunction(SemaRef, CallExpr.get(), BEF); |
| return ExprError(); |
| } |
| return CallExpr; |
| } |
| |
| } |
| |
| /// ActOnCXXForRangeStmt - Check and build a C++0x for-range statement. |
| /// |
| /// C++0x [stmt.ranged]: |
| /// A range-based for statement is equivalent to |
| /// |
| /// { |
| /// auto && __range = range-init; |
| /// for ( auto __begin = begin-expr, |
| /// __end = end-expr; |
| /// __begin != __end; |
| /// ++__begin ) { |
| /// for-range-declaration = *__begin; |
| /// statement |
| /// } |
| /// } |
| /// |
| /// The body of the loop is not available yet, since it cannot be analysed until |
| /// we have determined the type of the for-range-declaration. |
| StmtResult |
| Sema::ActOnCXXForRangeStmt(SourceLocation ForLoc, SourceLocation LParenLoc, |
| Stmt *First, SourceLocation ColonLoc, Expr *Range, |
| SourceLocation RParenLoc) { |
| if (!First || !Range) |
| return StmtError(); |
| |
| DeclStmt *DS = dyn_cast<DeclStmt>(First); |
| assert(DS && "first part of for range not a decl stmt"); |
| |
| if (!DS->isSingleDecl()) { |
| Diag(DS->getStartLoc(), diag::err_type_defined_in_for_range); |
| return StmtError(); |
| } |
| if (DS->getSingleDecl()->isInvalidDecl()) |
| return StmtError(); |
| |
| if (DiagnoseUnexpandedParameterPack(Range, UPPC_Expression)) |
| return StmtError(); |
| |
| // Build auto && __range = range-init |
| SourceLocation RangeLoc = Range->getLocStart(); |
| VarDecl *RangeVar = BuildForRangeVarDecl(*this, RangeLoc, |
| Context.getAutoRRefDeductType(), |
| "__range"); |
| if (FinishForRangeVarDecl(*this, RangeVar, Range, RangeLoc, |
| diag::err_for_range_deduction_failure)) |
| return StmtError(); |
| |
| // Claim the type doesn't contain auto: we've already done the checking. |
| DeclGroupPtrTy RangeGroup = |
| BuildDeclaratorGroup((Decl**)&RangeVar, 1, /*TypeMayContainAuto=*/false); |
| StmtResult RangeDecl = ActOnDeclStmt(RangeGroup, RangeLoc, RangeLoc); |
| if (RangeDecl.isInvalid()) |
| return StmtError(); |
| |
| return BuildCXXForRangeStmt(ForLoc, ColonLoc, RangeDecl.get(), |
| /*BeginEndDecl=*/0, /*Cond=*/0, /*Inc=*/0, DS, |
| RParenLoc); |
| } |
| |
| /// BuildCXXForRangeStmt - Build or instantiate a C++0x for-range statement. |
| StmtResult |
| Sema::BuildCXXForRangeStmt(SourceLocation ForLoc, SourceLocation ColonLoc, |
| Stmt *RangeDecl, Stmt *BeginEnd, Expr *Cond, |
| Expr *Inc, Stmt *LoopVarDecl, |
| SourceLocation RParenLoc) { |
| Scope *S = getCurScope(); |
| |
| DeclStmt *RangeDS = cast<DeclStmt>(RangeDecl); |
| VarDecl *RangeVar = cast<VarDecl>(RangeDS->getSingleDecl()); |
| QualType RangeVarType = RangeVar->getType(); |
| |
| DeclStmt *LoopVarDS = cast<DeclStmt>(LoopVarDecl); |
| VarDecl *LoopVar = cast<VarDecl>(LoopVarDS->getSingleDecl()); |
| |
| StmtResult BeginEndDecl = BeginEnd; |
| ExprResult NotEqExpr = Cond, IncrExpr = Inc; |
| |
| if (!BeginEndDecl.get() && !RangeVarType->isDependentType()) { |
| SourceLocation RangeLoc = RangeVar->getLocation(); |
| |
| const QualType RangeVarNonRefType = RangeVarType.getNonReferenceType(); |
| |
| ExprResult BeginRangeRef = BuildDeclRefExpr(RangeVar, RangeVarNonRefType, |
| VK_LValue, ColonLoc); |
| if (BeginRangeRef.isInvalid()) |
| return StmtError(); |
| |
| ExprResult EndRangeRef = BuildDeclRefExpr(RangeVar, RangeVarNonRefType, |
| VK_LValue, ColonLoc); |
| if (EndRangeRef.isInvalid()) |
| return StmtError(); |
| |
| QualType AutoType = Context.getAutoDeductType(); |
| Expr *Range = RangeVar->getInit(); |
| if (!Range) |
| return StmtError(); |
| QualType RangeType = Range->getType(); |
| |
| if (RequireCompleteType(RangeLoc, RangeType, |
| PDiag(diag::err_for_range_incomplete_type))) |
| return StmtError(); |
| |
| // Build auto __begin = begin-expr, __end = end-expr. |
| VarDecl *BeginVar = BuildForRangeVarDecl(*this, ColonLoc, AutoType, |
| "__begin"); |
| VarDecl *EndVar = BuildForRangeVarDecl(*this, ColonLoc, AutoType, |
| "__end"); |
| |
| // Build begin-expr and end-expr and attach to __begin and __end variables. |
| ExprResult BeginExpr, EndExpr; |
| if (const ArrayType *UnqAT = RangeType->getAsArrayTypeUnsafe()) { |
| // - if _RangeT is an array type, begin-expr and end-expr are __range and |
| // __range + __bound, respectively, where __bound is the array bound. If |
| // _RangeT is an array of unknown size or an array of incomplete type, |
| // the program is ill-formed; |
| |
| // begin-expr is __range. |
| BeginExpr = BeginRangeRef; |
| if (FinishForRangeVarDecl(*this, BeginVar, BeginRangeRef.get(), ColonLoc, |
| diag::err_for_range_iter_deduction_failure)) { |
| NoteForRangeBeginEndFunction(*this, BeginExpr.get(), BEF_begin); |
| return StmtError(); |
| } |
| |
| // Find the array bound. |
| ExprResult BoundExpr; |
| if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(UnqAT)) |
| BoundExpr = Owned(IntegerLiteral::Create(Context, CAT->getSize(), |
| Context.getPointerDiffType(), |
| RangeLoc)); |
| else if (const VariableArrayType *VAT = |
| dyn_cast<VariableArrayType>(UnqAT)) |
| BoundExpr = VAT->getSizeExpr(); |
| else { |
| // Can't be a DependentSizedArrayType or an IncompleteArrayType since |
| // UnqAT is not incomplete and Range is not type-dependent. |
| llvm_unreachable("Unexpected array type in for-range"); |
| } |
| |
| // end-expr is __range + __bound. |
| EndExpr = ActOnBinOp(S, ColonLoc, tok::plus, EndRangeRef.get(), |
| BoundExpr.get()); |
| if (EndExpr.isInvalid()) |
| return StmtError(); |
| if (FinishForRangeVarDecl(*this, EndVar, EndExpr.get(), ColonLoc, |
| diag::err_for_range_iter_deduction_failure)) { |
| NoteForRangeBeginEndFunction(*this, EndExpr.get(), BEF_end); |
| return StmtError(); |
| } |
| } else { |
| DeclarationNameInfo BeginNameInfo(&PP.getIdentifierTable().get("begin"), |
| ColonLoc); |
| DeclarationNameInfo EndNameInfo(&PP.getIdentifierTable().get("end"), |
| ColonLoc); |
| |
| LookupResult BeginMemberLookup(*this, BeginNameInfo, LookupMemberName); |
| LookupResult EndMemberLookup(*this, EndNameInfo, LookupMemberName); |
| |
| if (CXXRecordDecl *D = RangeType->getAsCXXRecordDecl()) { |
| // - if _RangeT is a class type, the unqualified-ids begin and end are |
| // looked up in the scope of class _RangeT as if by class member access |
| // lookup (3.4.5), and if either (or both) finds at least one |
| // declaration, begin-expr and end-expr are __range.begin() and |
| // __range.end(), respectively; |
| LookupQualifiedName(BeginMemberLookup, D); |
| LookupQualifiedName(EndMemberLookup, D); |
| |
| if (BeginMemberLookup.empty() != EndMemberLookup.empty()) { |
| Diag(ColonLoc, diag::err_for_range_member_begin_end_mismatch) |
| << RangeType << BeginMemberLookup.empty(); |
| return StmtError(); |
| } |
| } else { |
| // - otherwise, begin-expr and end-expr are begin(__range) and |
| // end(__range), respectively, where begin and end are looked up with |
| // argument-dependent lookup (3.4.2). For the purposes of this name |
| // lookup, namespace std is an associated namespace. |
| } |
| |
| BeginExpr = BuildForRangeBeginEndCall(*this, S, ColonLoc, BeginVar, |
| BEF_begin, BeginNameInfo, |
| BeginMemberLookup, |
| BeginRangeRef.get()); |
| if (BeginExpr.isInvalid()) |
| return StmtError(); |
| |
| EndExpr = BuildForRangeBeginEndCall(*this, S, ColonLoc, EndVar, |
| BEF_end, EndNameInfo, |
| EndMemberLookup, EndRangeRef.get()); |
| if (EndExpr.isInvalid()) |
| return StmtError(); |
| } |
| |
| // C++0x [decl.spec.auto]p6: BeginType and EndType must be the same. |
| QualType BeginType = BeginVar->getType(), EndType = EndVar->getType(); |
| if (!Context.hasSameType(BeginType, EndType)) { |
| Diag(RangeLoc, diag::err_for_range_begin_end_types_differ) |
| << BeginType << EndType; |
| NoteForRangeBeginEndFunction(*this, BeginExpr.get(), BEF_begin); |
| NoteForRangeBeginEndFunction(*this, EndExpr.get(), BEF_end); |
| } |
| |
| Decl *BeginEndDecls[] = { BeginVar, EndVar }; |
| // Claim the type doesn't contain auto: we've already done the checking. |
| DeclGroupPtrTy BeginEndGroup = |
| BuildDeclaratorGroup(BeginEndDecls, 2, /*TypeMayContainAuto=*/false); |
| BeginEndDecl = ActOnDeclStmt(BeginEndGroup, ColonLoc, ColonLoc); |
| |
| const QualType BeginRefNonRefType = BeginType.getNonReferenceType(); |
| ExprResult BeginRef = BuildDeclRefExpr(BeginVar, BeginRefNonRefType, |
| VK_LValue, ColonLoc); |
| if (BeginRef.isInvalid()) |
| return StmtError(); |
| |
| ExprResult EndRef = BuildDeclRefExpr(EndVar, EndType.getNonReferenceType(), |
| VK_LValue, ColonLoc); |
| if (EndRef.isInvalid()) |
| return StmtError(); |
| |
| // Build and check __begin != __end expression. |
| NotEqExpr = ActOnBinOp(S, ColonLoc, tok::exclaimequal, |
| BeginRef.get(), EndRef.get()); |
| NotEqExpr = ActOnBooleanCondition(S, ColonLoc, NotEqExpr.get()); |
| NotEqExpr = ActOnFinishFullExpr(NotEqExpr.get()); |
| if (NotEqExpr.isInvalid()) { |
| NoteForRangeBeginEndFunction(*this, BeginExpr.get(), BEF_begin); |
| if (!Context.hasSameType(BeginType, EndType)) |
| NoteForRangeBeginEndFunction(*this, EndExpr.get(), BEF_end); |
| return StmtError(); |
| } |
| |
| // Build and check ++__begin expression. |
| BeginRef = BuildDeclRefExpr(BeginVar, BeginRefNonRefType, |
| VK_LValue, ColonLoc); |
| if (BeginRef.isInvalid()) |
| return StmtError(); |
| |
| IncrExpr = ActOnUnaryOp(S, ColonLoc, tok::plusplus, BeginRef.get()); |
| IncrExpr = ActOnFinishFullExpr(IncrExpr.get()); |
| if (IncrExpr.isInvalid()) { |
| NoteForRangeBeginEndFunction(*this, BeginExpr.get(), BEF_begin); |
| return StmtError(); |
| } |
| |
| // Build and check *__begin expression. |
| BeginRef = BuildDeclRefExpr(BeginVar, BeginRefNonRefType, |
| VK_LValue, ColonLoc); |
| if (BeginRef.isInvalid()) |
| return StmtError(); |
| |
| ExprResult DerefExpr = ActOnUnaryOp(S, ColonLoc, tok::star, BeginRef.get()); |
| if (DerefExpr.isInvalid()) { |
| NoteForRangeBeginEndFunction(*this, BeginExpr.get(), BEF_begin); |
| return StmtError(); |
| } |
| |
| // Attach *__begin as initializer for VD. |
| if (!LoopVar->isInvalidDecl()) { |
| AddInitializerToDecl(LoopVar, DerefExpr.get(), /*DirectInit=*/false, |
| /*TypeMayContainAuto=*/true); |
| if (LoopVar->isInvalidDecl()) |
| NoteForRangeBeginEndFunction(*this, BeginExpr.get(), BEF_begin); |
| } |
| } else { |
| // The range is implicitly used as a placeholder when it is dependent. |
| RangeVar->setUsed(); |
| } |
| |
| return Owned(new (Context) CXXForRangeStmt(RangeDS, |
| cast_or_null<DeclStmt>(BeginEndDecl.get()), |
| NotEqExpr.take(), IncrExpr.take(), |
| LoopVarDS, /*Body=*/0, ForLoc, |
| ColonLoc, RParenLoc)); |
| } |
| |
| /// FinishCXXForRangeStmt - Attach the body to a C++0x for-range statement. |
| /// This is a separate step from ActOnCXXForRangeStmt because analysis of the |
| /// body cannot be performed until after the type of the range variable is |
| /// determined. |
| StmtResult Sema::FinishCXXForRangeStmt(Stmt *S, Stmt *B) { |
| if (!S || !B) |
| return StmtError(); |
| |
| cast<CXXForRangeStmt>(S)->setBody(B); |
| return S; |
| } |
| |
| StmtResult Sema::ActOnGotoStmt(SourceLocation GotoLoc, |
| SourceLocation LabelLoc, |
| LabelDecl *TheDecl) { |
| getCurFunction()->setHasBranchIntoScope(); |
| TheDecl->setUsed(); |
| return Owned(new (Context) GotoStmt(TheDecl, GotoLoc, LabelLoc)); |
| } |
| |
| StmtResult |
| Sema::ActOnIndirectGotoStmt(SourceLocation GotoLoc, SourceLocation StarLoc, |
| Expr *E) { |
| // Convert operand to void* |
| if (!E->isTypeDependent()) { |
| QualType ETy = E->getType(); |
| QualType DestTy = Context.getPointerType(Context.VoidTy.withConst()); |
| ExprResult ExprRes = Owned(E); |
| AssignConvertType ConvTy = |
| CheckSingleAssignmentConstraints(DestTy, ExprRes); |
| if (ExprRes.isInvalid()) |
| return StmtError(); |
| E = ExprRes.take(); |
| if (DiagnoseAssignmentResult(ConvTy, StarLoc, DestTy, ETy, E, AA_Passing)) |
| return StmtError(); |
| } |
| |
| getCurFunction()->setHasIndirectGoto(); |
| |
| return Owned(new (Context) IndirectGotoStmt(GotoLoc, StarLoc, E)); |
| } |
| |
| StmtResult |
| 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)); |
| } |
| |
| StmtResult |
| 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)); |
| } |
| |
| /// \brief Determine whether the given expression is a candidate for |
| /// copy elision in either a return statement or a throw expression. |
| /// |
| /// \param ReturnType If we're determining the copy elision candidate for |
| /// a return statement, this is the return type of the function. If we're |
| /// determining the copy elision candidate for a throw expression, this will |
| /// be a NULL type. |
| /// |
| /// \param E The expression being returned from the function or block, or |
| /// being thrown. |
| /// |
| /// \param AllowFunctionParameter Whether we allow function parameters to |
| /// be considered NRVO candidates. C++ prohibits this for NRVO itself, but |
| /// we re-use this logic to determine whether we should try to move as part of |
| /// a return or throw (which does allow function parameters). |
| /// |
| /// \returns The NRVO candidate variable, if the return statement may use the |
| /// NRVO, or NULL if there is no such candidate. |
| const VarDecl *Sema::getCopyElisionCandidate(QualType ReturnType, |
| Expr *E, |
| bool AllowFunctionParameter) { |
| QualType ExprType = E->getType(); |
| // - in a return statement in a function with ... |
| // ... a class return type ... |
| if (!ReturnType.isNull()) { |
| if (!ReturnType->isRecordType()) |
| return 0; |
| // ... the same cv-unqualified type as the function return type ... |
| if (!Context.hasSameUnqualifiedType(ReturnType, ExprType)) |
| return 0; |
| } |
| |
| // ... the expression is the name of a non-volatile automatic object |
| // (other than a function or catch-clause parameter)) ... |
| const DeclRefExpr *DR = dyn_cast<DeclRefExpr>(E->IgnoreParens()); |
| if (!DR) |
| return 0; |
| const VarDecl *VD = dyn_cast<VarDecl>(DR->getDecl()); |
| if (!VD) |
| return 0; |
| |
| // ...object (other than a function or catch-clause parameter)... |
| if (VD->getKind() != Decl::Var && |
| !(AllowFunctionParameter && VD->getKind() == Decl::ParmVar)) |
| return 0; |
| if (VD->isExceptionVariable()) return 0; |
| |
| // ...automatic... |
| if (!VD->hasLocalStorage()) return 0; |
| |
| // ...non-volatile... |
| if (VD->getType().isVolatileQualified()) return 0; |
| if (VD->getType()->isReferenceType()) return 0; |
| |
| // __block variables can't be allocated in a way that permits NRVO. |
| if (VD->hasAttr<BlocksAttr>()) return 0; |
| |
| // Variables with higher required alignment than their type's ABI |
| // alignment cannot use NRVO. |
| if (VD->hasAttr<AlignedAttr>() && |
| Context.getDeclAlign(VD) > Context.getTypeAlignInChars(VD->getType())) |
| return 0; |
| |
| return VD; |
| } |
| |
| /// \brief Perform the initialization of a potentially-movable value, which |
| /// is the result of return value. |
| /// |
| /// This routine implements C++0x [class.copy]p33, which attempts to treat |
| /// returned lvalues as rvalues in certain cases (to prefer move construction), |
| /// then falls back to treating them as lvalues if that failed. |
| ExprResult |
| Sema::PerformMoveOrCopyInitialization(const InitializedEntity &Entity, |
| const VarDecl *NRVOCandidate, |
| QualType ResultType, |
| Expr *Value, |
| bool AllowNRVO) { |
| // C++0x [class.copy]p33: |
| // When the criteria for elision of a copy operation are met or would |
| // be met save for the fact that the source object is a function |
| // parameter, 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. |
| ExprResult Res = ExprError(); |
| if (AllowNRVO && |
| (NRVOCandidate || getCopyElisionCandidate(ResultType, Value, true))) { |
| ImplicitCastExpr AsRvalue(ImplicitCastExpr::OnStack, |
| Value->getType(), CK_LValueToRValue, |
| Value, VK_XValue); |
| |
| Expr *InitExpr = &AsRvalue; |
| InitializationKind Kind |
| = InitializationKind::CreateCopy(Value->getLocStart(), |
| Value->getLocStart()); |
| InitializationSequence Seq(*this, Entity, Kind, &InitExpr, 1); |
| |
| // [...] If overload resolution fails, or if the type of the first |
| // parameter of the selected constructor is not an rvalue reference |
| // to the object's type (possibly cv-qualified), overload resolution |
| // is performed again, considering the object as an lvalue. |
| if (Seq) { |
| for (InitializationSequence::step_iterator Step = Seq.step_begin(), |
| StepEnd = Seq.step_end(); |
| Step != StepEnd; ++Step) { |
| if (Step->Kind != InitializationSequence::SK_ConstructorInitialization) |
| continue; |
| |
| CXXConstructorDecl *Constructor |
| = cast<CXXConstructorDecl>(Step->Function.Function); |
| |
| const RValueReferenceType *RRefType |
| = Constructor->getParamDecl(0)->getType() |
| ->getAs<RValueReferenceType>(); |
| |
| // If we don't meet the criteria, break out now. |
| if (!RRefType || |
| !Context.hasSameUnqualifiedType(RRefType->getPointeeType(), |
| Context.getTypeDeclType(Constructor->getParent()))) |
| break; |
| |
| // Promote "AsRvalue" to the heap, since we now need this |
| // expression node to persist. |
| Value = ImplicitCastExpr::Create(Context, Value->getType(), |
| CK_LValueToRValue, Value, 0, |
| VK_XValue); |
| |
| // Complete type-checking the initialization of the return type |
| // using the constructor we found. |
| Res = Seq.Perform(*this, Entity, Kind, MultiExprArg(&Value, 1)); |
| } |
| } |
| } |
| |
| // Either we didn't meet the criteria for treating an lvalue as an rvalue, |
| // above, or overload resolution failed. Either way, we need to try |
| // (again) now with the return value expression as written. |
| if (Res.isInvalid()) |
| Res = PerformCopyInitialization(Entity, SourceLocation(), Value); |
| |
| return Res; |
| } |
| |
| /// ActOnBlockReturnStmt - Utility routine to figure out block's return type. |
| /// |
| StmtResult |
| 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. |
| BlockScopeInfo *CurBlock = getCurBlock(); |
| if (CurBlock->TheDecl->blockMissingReturnType()) { |
| QualType BlockReturnT; |
| if (RetValExp) { |
| // Don't call UsualUnaryConversions(), since we don't want to do |
| // integer promotions here. |
| ExprResult Result = DefaultFunctionArrayLvalueConversion(RetValExp); |
| if (Result.isInvalid()) |
| return StmtError(); |
| RetValExp = Result.take(); |
| |
| if (!RetValExp->isTypeDependent()) { |
| BlockReturnT = 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.removeLocalConst(); // FIXME: local??? |
| } |
| } else |
| BlockReturnT = Context.DependentTy; |
| } else |
| BlockReturnT = Context.VoidTy; |
| if (!CurBlock->ReturnType.isNull() && !CurBlock->ReturnType->isDependentType() |
| && !BlockReturnT->isDependentType() |
| // when block's return type is not specified, all return types |
| // must strictly match. |
| && !Context.hasSameType(BlockReturnT, CurBlock->ReturnType)) { |
| Diag(ReturnLoc, diag::err_typecheck_missing_return_type_incompatible) |
| << BlockReturnT << CurBlock->ReturnType; |
| return StmtError(); |
| } |
| CurBlock->ReturnType = BlockReturnT; |
| } |
| QualType FnRetType = CurBlock->ReturnType; |
| |
| if (CurBlock->FunctionType->getAs<FunctionType>()->getNoReturnAttr()) { |
| Diag(ReturnLoc, diag::err_noreturn_block_has_return_expr); |
| 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. |
| const VarDecl *NRVOCandidate = 0; |
| if (FnRetType->isDependentType()) { |
| // Delay processing for now. TODO: there are lots of dependent |
| // types we can conclusively prove aren't void. |
| } else if (FnRetType->isVoidType()) { |
| if (RetValExp && |
| !(getLangOptions().CPlusPlus && |
| (RetValExp->isTypeDependent() || |
| RetValExp->getType()->isVoidType()))) { |
| Diag(ReturnLoc, diag::err_return_block_has_expr); |
| RetValExp = 0; |
| } |
| } else if (!RetValExp) { |
| return StmtError(Diag(ReturnLoc, diag::err_block_return_missing_expr)); |
| } else if (!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. |
| NRVOCandidate = getCopyElisionCandidate(FnRetType, RetValExp, false); |
| InitializedEntity Entity = InitializedEntity::InitializeResult(ReturnLoc, |
| FnRetType, |
| NRVOCandidate != 0); |
| ExprResult Res = PerformMoveOrCopyInitialization(Entity, NRVOCandidate, |
| FnRetType, RetValExp); |
| if (Res.isInvalid()) { |
| // FIXME: Cleanup temporaries here, anyway? |
| return StmtError(); |
| } |
| RetValExp = Res.take(); |
| CheckReturnStackAddr(RetValExp, FnRetType, ReturnLoc); |
| } |
| |
| if (RetValExp) { |
| CheckImplicitConversions(RetValExp, ReturnLoc); |
| RetValExp = MaybeCreateExprWithCleanups(RetValExp); |
| } |
| ReturnStmt *Result = new (Context) ReturnStmt(ReturnLoc, RetValExp, |
| NRVOCandidate); |
| |
| // If we need to check for the named return value optimization, save the |
| // return statement in our scope for later processing. |
| if (getLangOptions().CPlusPlus && FnRetType->isRecordType() && |
| !CurContext->isDependentContext()) |
| FunctionScopes.back()->Returns.push_back(Result); |
| |
| return Owned(Result); |
| } |
| |
| StmtResult |
| Sema::ActOnReturnStmt(SourceLocation ReturnLoc, Expr *RetValExp) { |
| // Check for unexpanded parameter packs. |
| if (RetValExp && DiagnoseUnexpandedParameterPack(RetValExp)) |
| return StmtError(); |
| |
| if (getCurBlock()) |
| return ActOnBlockReturnStmt(ReturnLoc, RetValExp); |
| |
| QualType FnRetType; |
| QualType DeclaredRetType; |
| if (const FunctionDecl *FD = getCurFunctionDecl()) { |
| FnRetType = FD->getResultType(); |
| DeclaredRetType = FnRetType; |
| if (FD->hasAttr<NoReturnAttr>() || |
| FD->getType()->getAs<FunctionType>()->getNoReturnAttr()) |
| Diag(ReturnLoc, diag::warn_noreturn_function_has_return_expr) |
| << FD->getDeclName(); |
| } else if (ObjCMethodDecl *MD = getCurMethodDecl()) { |
| DeclaredRetType = MD->getResultType(); |
| if (MD->hasRelatedResultType() && MD->getClassInterface()) { |
| // In the implementation of a method with a related return type, the |
| // type used to type-check the validity of return statements within the |
| // method body is a pointer to the type of the class being implemented. |
| FnRetType = Context.getObjCInterfaceType(MD->getClassInterface()); |
| FnRetType = Context.getObjCObjectPointerType(FnRetType); |
| } else { |
| FnRetType = DeclaredRetType; |
| } |
| } else // If we don't have a function/method context, bail. |
| return StmtError(); |
| |
| ReturnStmt *Result = 0; |
| if (FnRetType->isVoidType()) { |
| if (RetValExp) { |
| if (!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; |
| else { |
| ExprResult Result = Owned(RetValExp); |
| Result = IgnoredValueConversions(Result.take()); |
| if (Result.isInvalid()) |
| return StmtError(); |
| RetValExp = Result.take(); |
| RetValExp = ImpCastExprToType(RetValExp, |
| Context.VoidTy, CK_ToVoid).take(); |
| } |
| |
| // return (some void expression); is legal in C++. |
| if (D != diag::ext_return_has_void_expr || |
| !getLangOptions().CPlusPlus) { |
| NamedDecl *CurDecl = getCurFunctionOrMethodDecl(); |
| |
| int FunctionKind = 0; |
| if (isa<ObjCMethodDecl>(CurDecl)) |
| FunctionKind = 1; |
| else if (isa<CXXConstructorDecl>(CurDecl)) |
| FunctionKind = 2; |
| else if (isa<CXXDestructorDecl>(CurDecl)) |
| FunctionKind = 3; |
| |
| Diag(ReturnLoc, D) |
| << CurDecl->getDeclName() << FunctionKind |
| << RetValExp->getSourceRange(); |
| } |
| } |
| |
| CheckImplicitConversions(RetValExp, ReturnLoc); |
| RetValExp = MaybeCreateExprWithCleanups(RetValExp); |
| } |
| |
| Result = new (Context) ReturnStmt(ReturnLoc, RetValExp, 0); |
| } else 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*/; |
| Result = new (Context) ReturnStmt(ReturnLoc); |
| } else { |
| const VarDecl *NRVOCandidate = 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. |
| |
| // In C++ the return statement is handled via a copy initialization, |
| // the C version of which boils down to CheckSingleAssignmentConstraints. |
| NRVOCandidate = getCopyElisionCandidate(FnRetType, RetValExp, false); |
| InitializedEntity Entity = InitializedEntity::InitializeResult(ReturnLoc, |
| FnRetType, |
| NRVOCandidate != 0); |
| ExprResult Res = PerformMoveOrCopyInitialization(Entity, NRVOCandidate, |
| FnRetType, RetValExp); |
| if (Res.isInvalid()) { |
| // FIXME: Cleanup temporaries here, anyway? |
| return StmtError(); |
| } |
| |
| RetValExp = Res.takeAs<Expr>(); |
| if (RetValExp) |
| CheckReturnStackAddr(RetValExp, FnRetType, ReturnLoc); |
| } |
| |
| if (RetValExp) { |
| // If we type-checked an Objective-C method's return type based |
| // on a related return type, we may need to adjust the return |
| // type again. Do so now. |
| if (DeclaredRetType != FnRetType) { |
| ExprResult result = PerformImplicitConversion(RetValExp, |
| DeclaredRetType, |
| AA_Returning); |
| if (result.isInvalid()) return StmtError(); |
| RetValExp = result.take(); |
| } |
| |
| CheckImplicitConversions(RetValExp, ReturnLoc); |
| RetValExp = MaybeCreateExprWithCleanups(RetValExp); |
| } |
| Result = new (Context) ReturnStmt(ReturnLoc, RetValExp, NRVOCandidate); |
| } |
| |
| // If we need to check for the named return value optimization, save the |
| // return statement in our scope for later processing. |
| if (getLangOptions().CPlusPlus && FnRetType->isRecordType() && |
| !CurContext->isDependentContext()) |
| FunctionScopes.back()->Returns.push_back(Result); |
| |
| return Owned(Result); |
| } |
| |
| /// 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()) |
| 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()) { |
| 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; |
| } |
| |
| /// isOperandMentioned - Return true if the specified operand # is mentioned |
| /// anywhere in the decomposed asm string. |
| static bool isOperandMentioned(unsigned OpNo, |
| ArrayRef<AsmStmt::AsmStringPiece> AsmStrPieces) { |
| for (unsigned p = 0, e = AsmStrPieces.size(); p != e; ++p) { |
| const AsmStmt::AsmStringPiece &Piece = AsmStrPieces[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() == OpNo) |
| return true; |
| } |
| |
| return false; |
| } |
| |
| StmtResult Sema::ActOnAsmStmt(SourceLocation AsmLoc, bool IsSimple, |
| bool IsVolatile, unsigned NumOutputs, |
| unsigned NumInputs, IdentifierInfo **Names, |
| MultiExprArg constraints, MultiExprArg exprs, |
| Expr *asmString, MultiExprArg clobbers, |
| SourceLocation RParenLoc, bool MSAsm) { |
| unsigned NumClobbers = clobbers.size(); |
| StringLiteral **Constraints = |
| reinterpret_cast<StringLiteral**>(constraints.get()); |
| Expr **Exprs = exprs.get(); |
| StringLiteral *AsmString = cast<StringLiteral>(asmString); |
| StringLiteral **Clobbers = reinterpret_cast<StringLiteral**>(clobbers.get()); |
| |
| SmallVector<TargetInfo::ConstraintInfo, 4> OutputConstraintInfos; |
| |
| // The parser verifies that there is a string literal here. |
| if (!AsmString->isAscii()) |
| 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->isAscii()) |
| return StmtError(Diag(Literal->getLocStart(),diag::err_asm_wide_character) |
| << Literal->getSourceRange()); |
| |
| StringRef OutputName; |
| if (Names[i]) |
| OutputName = Names[i]->getName(); |
| |
| TargetInfo::ConstraintInfo Info(Literal->getString(), OutputName); |
| if (!Context.getTargetInfo().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); |
| } |
| |
| SmallVector<TargetInfo::ConstraintInfo, 4> InputConstraintInfos; |
| |
| for (unsigned i = NumOutputs, e = NumOutputs + NumInputs; i != e; i++) { |
| StringLiteral *Literal = Constraints[i]; |
| if (!Literal->isAscii()) |
| return StmtError(Diag(Literal->getLocStart(),diag::err_asm_wide_character) |
| << Literal->getSourceRange()); |
| |
| StringRef InputName; |
| if (Names[i]) |
| InputName = Names[i]->getName(); |
| |
| TargetInfo::ConstraintInfo Info(Literal->getString(), InputName); |
| if (!Context.getTargetInfo().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()); |
| } |
| } |
| |
| ExprResult Result = DefaultFunctionArrayLvalueConversion(Exprs[i]); |
| if (Result.isInvalid()) |
| return StmtError(); |
| |
| Exprs[i] = Result.take(); |
| InputConstraintInfos.push_back(Info); |
| } |
| |
| // Check that the clobbers are valid. |
| for (unsigned i = 0; i != NumClobbers; i++) { |
| StringLiteral *Literal = Clobbers[i]; |
| if (!Literal->isAscii()) |
| return StmtError(Diag(Literal->getLocStart(),diag::err_asm_wide_character) |
| << Literal->getSourceRange()); |
| |
| StringRef Clobber = Literal->getString(); |
| |
| if (!Context.getTargetInfo().isValidClobber(Clobber)) |
| return StmtError(Diag(Literal->getLocStart(), |
| diag::err_asm_unknown_register_name) << Clobber); |
| } |
| |
| AsmStmt *NS = |
| new (Context) AsmStmt(Context, 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. |
| SmallVector<AsmStmt::AsmStringPiece, 8> Pieces; |
| unsigned DiagOffs; |
| if (unsigned DiagID = NS->AnalyzeAsmString(Pieces, Context, DiagOffs)) { |
| Diag(getLocationOfStringLiteralByte(AsmString, DiagOffs), DiagID) |
| << AsmString->getSourceRange(); |
| 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(); |
| unsigned InputOpNo = i+NumOutputs; |
| Expr *OutputExpr = Exprs[TiedTo]; |
| Expr *InputExpr = Exprs[InputOpNo]; |
| |
| if (OutputExpr->isTypeDependent() || InputExpr->isTypeDependent()) |
| continue; |
| |
| QualType InTy = InputExpr->getType(); |
| QualType OutTy = OutputExpr->getType(); |
| if (Context.hasSameType(InTy, OutTy)) |
| continue; // All types can be tied to themselves. |
| |
| // Decide if the input and output are in the same domain (integer/ptr or |
| // floating point. |
| enum AsmDomain { |
| AD_Int, AD_FP, AD_Other |
| } InputDomain, OutputDomain; |
| |
| if (InTy->isIntegerType() || InTy->isPointerType()) |
| InputDomain = AD_Int; |
| else if (InTy->isRealFloatingType()) |
| InputDomain = AD_FP; |
| else |
| InputDomain = AD_Other; |
| |
| if (OutTy->isIntegerType() || OutTy->isPointerType()) |
| OutputDomain = AD_Int; |
| else if (OutTy->isRealFloatingType()) |
| OutputDomain = AD_FP; |
| else |
| OutputDomain = AD_Other; |
| |
| // They are ok if they are the same size and in the same domain. This |
| // allows tying things like: |
| // void* to int* |
| // void* to int if they are the same size. |
| // double to long double if they are the same size. |
| // |
| uint64_t OutSize = Context.getTypeSize(OutTy); |
| uint64_t InSize = Context.getTypeSize(InTy); |
| if (OutSize == InSize && InputDomain == OutputDomain && |
| InputDomain != AD_Other) |
| continue; |
| |
| // If the smaller input/output operand is not mentioned in the asm string, |
| // then we can promote the smaller one to a larger input and the asm string |
| // won't notice. |
| bool SmallerValueMentioned = false; |
| |
| // If this is a reference to the input and if the input was the smaller |
| // one, then we have to reject this asm. |
| if (isOperandMentioned(InputOpNo, Pieces)) { |
| // This is a use in the asm string of the smaller operand. Since we |
| // codegen this by promoting to a wider value, the asm will get printed |
| // "wrong". |
| SmallerValueMentioned |= InSize < OutSize; |
| } |
| if (isOperandMentioned(TiedTo, Pieces)) { |
| // If this is a reference to the output, and if the output is the larger |
| // value, then it's ok because we'll promote the input to the larger type. |
| SmallerValueMentioned |= OutSize < InSize; |
| } |
| |
| // 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 && InputDomain != AD_Other && |
| OutputConstraintInfos[TiedTo].allowsRegister()) |
| continue; |
| |
| // Either both of the operands were mentioned or the smaller one was |
| // mentioned. One more special case that we'll allow: if the tied input is |
| // integer, unmentioned, and is a constant, then we'll allow truncating it |
| // down to the size of the destination. |
| if (InputDomain == AD_Int && OutputDomain == AD_Int && |
| !isOperandMentioned(InputOpNo, Pieces) && |
| InputExpr->isEvaluatable(Context)) { |
| CastKind castKind = |
| (OutTy->isBooleanType() ? CK_IntegralToBoolean : CK_IntegralCast); |
| InputExpr = ImpCastExprToType(InputExpr, OutTy, castKind).take(); |
| Exprs[InputOpNo] = InputExpr; |
| NS->setInputExpr(i, InputExpr); |
| continue; |
| } |
| |
| Diag(InputExpr->getLocStart(), |
| diag::err_asm_tying_incompatible_types) |
| << InTy << OutTy << OutputExpr->getSourceRange() |
| << InputExpr->getSourceRange(); |
| return StmtError(); |
| } |
| |
| return Owned(NS); |
| } |
| |
| StmtResult |
| Sema::ActOnObjCAtCatchStmt(SourceLocation AtLoc, |
| SourceLocation RParen, Decl *Parm, |
| Stmt *Body) { |
| VarDecl *Var = cast_or_null<VarDecl>(Parm); |
| if (Var && Var->isInvalidDecl()) |
| return StmtError(); |
| |
| return Owned(new (Context) ObjCAtCatchStmt(AtLoc, RParen, Var, Body)); |
| } |
| |
| StmtResult |
| Sema::ActOnObjCAtFinallyStmt(SourceLocation AtLoc, Stmt *Body) { |
| return Owned(new (Context) ObjCAtFinallyStmt(AtLoc, Body)); |
| } |
| |
| StmtResult |
| Sema::ActOnObjCAtTryStmt(SourceLocation AtLoc, Stmt *Try, |
| MultiStmtArg CatchStmts, Stmt *Finally) { |
| if (!getLangOptions().ObjCExceptions) |
| Diag(AtLoc, diag::err_objc_exceptions_disabled) << "@try"; |
| |
| getCurFunction()->setHasBranchProtectedScope(); |
| unsigned NumCatchStmts = CatchStmts.size(); |
| return Owned(ObjCAtTryStmt::Create(Context, AtLoc, Try, |
| CatchStmts.release(), |
| NumCatchStmts, |
| Finally)); |
| } |
| |
| StmtResult Sema::BuildObjCAtThrowStmt(SourceLocation AtLoc, |
| Expr *Throw) { |
| if (Throw) { |
| Throw = MaybeCreateExprWithCleanups(Throw); |
| ExprResult Result = DefaultLvalueConversion(Throw); |
| if (Result.isInvalid()) |
| return StmtError(); |
| |
| Throw = Result.take(); |
| QualType ThrowType = Throw->getType(); |
| // Make sure the expression type is an ObjC pointer or "void *". |
| if (!ThrowType->isDependentType() && |
| !ThrowType->isObjCObjectPointerType()) { |
| const PointerType *PT = ThrowType->getAs<PointerType>(); |
| if (!PT || !PT->getPointeeType()->isVoidType()) |
| return StmtError(Diag(AtLoc, diag::error_objc_throw_expects_object) |
| << Throw->getType() << Throw->getSourceRange()); |
| } |
| } |
| |
| return Owned(new (Context) ObjCAtThrowStmt(AtLoc, Throw)); |
| } |
| |
| StmtResult |
| Sema::ActOnObjCAtThrowStmt(SourceLocation AtLoc, Expr *Throw, |
| Scope *CurScope) { |
| if (!getLangOptions().ObjCExceptions) |
| Diag(AtLoc, diag::err_objc_exceptions_disabled) << "@throw"; |
| |
| if (!Throw) { |
| // @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)); |
| } |
| |
| return BuildObjCAtThrowStmt(AtLoc, Throw); |
| } |
| |
| ExprResult |
| Sema::ActOnObjCAtSynchronizedOperand(SourceLocation atLoc, Expr *operand) { |
| ExprResult result = DefaultLvalueConversion(operand); |
| if (result.isInvalid()) |
| return ExprError(); |
| operand = result.take(); |
| |
| // Make sure the expression type is an ObjC pointer or "void *". |
| QualType type = operand->getType(); |
| if (!type->isDependentType() && |
| !type->isObjCObjectPointerType()) { |
| const PointerType *pointerType = type->getAs<PointerType>(); |
| if (!pointerType || !pointerType->getPointeeType()->isVoidType()) |
| return Diag(atLoc, diag::error_objc_synchronized_expects_object) |
| << type << operand->getSourceRange(); |
| } |
| |
| // The operand to @synchronized is a full-expression. |
| return MaybeCreateExprWithCleanups(operand); |
| } |
| |
| StmtResult |
| Sema::ActOnObjCAtSynchronizedStmt(SourceLocation AtLoc, Expr *SyncExpr, |
| Stmt *SyncBody) { |
| // We can't jump into or indirect-jump out of a @synchronized block. |
| getCurFunction()->setHasBranchProtectedScope(); |
| return Owned(new (Context) ObjCAtSynchronizedStmt(AtLoc, SyncExpr, SyncBody)); |
| } |
| |
| /// ActOnCXXCatchBlock - Takes an exception declaration and a handler block |
| /// and creates a proper catch handler from them. |
| StmtResult |
| Sema::ActOnCXXCatchBlock(SourceLocation CatchLoc, Decl *ExDecl, |
| Stmt *HandlerBlock) { |
| // There's nothing to test that ActOnExceptionDecl didn't already test. |
| return Owned(new (Context) CXXCatchStmt(CatchLoc, |
| cast_or_null<VarDecl>(ExDecl), |
| HandlerBlock)); |
| } |
| |
| StmtResult |
| Sema::ActOnObjCAutoreleasePoolStmt(SourceLocation AtLoc, Stmt *Body) { |
| getCurFunction()->setHasBranchProtectedScope(); |
| return Owned(new (Context) ObjCAutoreleasePoolStmt(AtLoc, Body)); |
| } |
| |
| namespace { |
| |
| 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; |
| } |
| |
| 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. |
| StmtResult |
| Sema::ActOnCXXTryBlock(SourceLocation TryLoc, Stmt *TryBlock, |
| MultiStmtArg RawHandlers) { |
| // Don't report an error if 'try' is used in system headers. |
| if (!getLangOptions().CXXExceptions && |
| !getSourceManager().isInSystemHeader(TryLoc)) |
| Diag(TryLoc, diag::err_exceptions_disabled) << "try"; |
| |
| unsigned NumHandlers = RawHandlers.size(); |
| assert(NumHandlers > 0 && |
| "The parser shouldn't call this if there are no handlers."); |
| Stmt **Handlers = RawHandlers.get(); |
| |
| SmallVector<TypeWithHandler, 8> TypesWithHandlers; |
| |
| for (unsigned i = 0; i < NumHandlers; ++i) { |
| CXXCatchStmt *Handler = 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; |
| } |
| } |
| |
| getCurFunction()->setHasBranchProtectedScope(); |
| |
| // 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. |
| |
| return Owned(CXXTryStmt::Create(Context, TryLoc, TryBlock, |
| Handlers, NumHandlers)); |
| } |
| |
| StmtResult |
| Sema::ActOnSEHTryBlock(bool IsCXXTry, |
| SourceLocation TryLoc, |
| Stmt *TryBlock, |
| Stmt *Handler) { |
| assert(TryBlock && Handler); |
| |
| getCurFunction()->setHasBranchProtectedScope(); |
| |
| return Owned(SEHTryStmt::Create(Context,IsCXXTry,TryLoc,TryBlock,Handler)); |
| } |
| |
| StmtResult |
| Sema::ActOnSEHExceptBlock(SourceLocation Loc, |
| Expr *FilterExpr, |
| Stmt *Block) { |
| assert(FilterExpr && Block); |
| |
| if(!FilterExpr->getType()->isIntegerType()) { |
| return StmtError(Diag(FilterExpr->getExprLoc(), |
| diag::err_filter_expression_integral) |
| << FilterExpr->getType()); |
| } |
| |
| return Owned(SEHExceptStmt::Create(Context,Loc,FilterExpr,Block)); |
| } |
| |
| StmtResult |
| Sema::ActOnSEHFinallyBlock(SourceLocation Loc, |
| Stmt *Block) { |
| assert(Block); |
| return Owned(SEHFinallyStmt::Create(Context,Loc,Block)); |
| } |
| |
| StmtResult Sema::BuildMSDependentExistsStmt(SourceLocation KeywordLoc, |
| bool IsIfExists, |
| NestedNameSpecifierLoc QualifierLoc, |
| DeclarationNameInfo NameInfo, |
| Stmt *Nested) |
| { |
| return new (Context) MSDependentExistsStmt(KeywordLoc, IsIfExists, |
| QualifierLoc, NameInfo, |
| cast<CompoundStmt>(Nested)); |
| } |
| |
| |
| StmtResult Sema::ActOnMSDependentExistsStmt(SourceLocation KeywordLoc, |
| bool IsIfExists, |
| CXXScopeSpec &SS, |
| UnqualifiedId &Name, |
| Stmt *Nested) { |
| return BuildMSDependentExistsStmt(KeywordLoc, IsIfExists, |
| SS.getWithLocInContext(Context), |
| GetNameFromUnqualifiedId(Name), |
| Nested); |
| } |