Check in LLVM r95781.
diff --git a/lib/Sema/SemaStmt.cpp b/lib/Sema/SemaStmt.cpp
new file mode 100644
index 0000000..50479a9
--- /dev/null
+++ b/lib/Sema/SemaStmt.cpp
@@ -0,0 +1,1644 @@
+//===--- SemaStmt.cpp - Semantic Analysis for Statements ------------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements semantic analysis for statements.
+//
+//===----------------------------------------------------------------------===//
+
+#include "Sema.h"
+#include "SemaInit.h"
+#include "clang/AST/APValue.h"
+#include "clang/AST/ASTContext.h"
+#include "clang/AST/DeclObjC.h"
+#include "clang/AST/ExprCXX.h"
+#include "clang/AST/ExprObjC.h"
+#include "clang/AST/StmtObjC.h"
+#include "clang/AST/StmtCXX.h"
+#include "clang/Lex/Preprocessor.h"
+#include "clang/Basic/TargetInfo.h"
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/ADT/SmallVector.h"
+using namespace clang;
+
+Sema::OwningStmtResult Sema::ActOnExprStmt(FullExprArg expr) {
+ Expr *E = expr->takeAs<Expr>();
+ assert(E && "ActOnExprStmt(): missing expression");
+ if (E->getType()->isObjCInterfaceType()) {
+ if (LangOpts.ObjCNonFragileABI)
+ Diag(E->getLocEnd(), diag::err_indirection_requires_nonfragile_object)
+ << E->getType();
+ else
+ Diag(E->getLocEnd(), diag::err_direct_interface_unsupported)
+ << E->getType();
+ return StmtError();
+ }
+ // C99 6.8.3p2: The expression in an expression statement is evaluated as a
+ // void expression for its side effects. Conversion to void allows any
+ // operand, even incomplete types.
+
+ // Same thing in for stmt first clause (when expr) and third clause.
+ return Owned(static_cast<Stmt*>(E));
+}
+
+
+Sema::OwningStmtResult Sema::ActOnNullStmt(SourceLocation SemiLoc) {
+ return Owned(new (Context) NullStmt(SemiLoc));
+}
+
+Sema::OwningStmtResult Sema::ActOnDeclStmt(DeclGroupPtrTy dg,
+ SourceLocation StartLoc,
+ SourceLocation EndLoc) {
+ DeclGroupRef DG = dg.getAsVal<DeclGroupRef>();
+
+ // If we have an invalid decl, just return an error.
+ if (DG.isNull()) return StmtError();
+
+ return Owned(new (Context) DeclStmt(DG, StartLoc, EndLoc));
+}
+
+void Sema::ActOnForEachDeclStmt(DeclGroupPtrTy dg) {
+ DeclGroupRef DG = dg.getAsVal<DeclGroupRef>();
+
+ // If we have an invalid decl, just return.
+ if (DG.isNull() || !DG.isSingleDecl()) return;
+ // suppress any potential 'unused variable' warning.
+ DG.getSingleDecl()->setUsed();
+}
+
+void Sema::DiagnoseUnusedExprResult(const Stmt *S) {
+ const Expr *E = dyn_cast_or_null<Expr>(S);
+ if (!E)
+ return;
+
+ // Ignore expressions that have void type.
+ if (E->getType()->isVoidType())
+ return;
+
+ SourceLocation Loc;
+ SourceRange R1, R2;
+ if (!E->isUnusedResultAWarning(Loc, R1, R2, Context))
+ return;
+
+ // Okay, we have an unused result. Depending on what the base expression is,
+ // we might want to make a more specific diagnostic. Check for one of these
+ // cases now.
+ unsigned DiagID = diag::warn_unused_expr;
+ E = E->IgnoreParens();
+ if (isa<ObjCImplicitSetterGetterRefExpr>(E))
+ DiagID = diag::warn_unused_property_expr;
+
+ if (const CallExpr *CE = dyn_cast<CallExpr>(E)) {
+ // If the callee has attribute pure, const, or warn_unused_result, warn with
+ // a more specific message to make it clear what is happening.
+ if (const Decl *FD = CE->getCalleeDecl()) {
+ if (FD->getAttr<WarnUnusedResultAttr>()) {
+ Diag(Loc, diag::warn_unused_call) << R1 << R2 << "warn_unused_result";
+ return;
+ }
+ if (FD->getAttr<PureAttr>()) {
+ Diag(Loc, diag::warn_unused_call) << R1 << R2 << "pure";
+ return;
+ }
+ if (FD->getAttr<ConstAttr>()) {
+ Diag(Loc, diag::warn_unused_call) << R1 << R2 << "const";
+ return;
+ }
+ }
+ }
+
+ Diag(Loc, DiagID) << R1 << R2;
+}
+
+Action::OwningStmtResult
+Sema::ActOnCompoundStmt(SourceLocation L, SourceLocation R,
+ MultiStmtArg elts, bool isStmtExpr) {
+ unsigned NumElts = elts.size();
+ Stmt **Elts = reinterpret_cast<Stmt**>(elts.release());
+ // If we're in C89 mode, check that we don't have any decls after stmts. If
+ // so, emit an extension diagnostic.
+ if (!getLangOptions().C99 && !getLangOptions().CPlusPlus) {
+ // Note that __extension__ can be around a decl.
+ unsigned i = 0;
+ // Skip over all declarations.
+ for (; i != NumElts && isa<DeclStmt>(Elts[i]); ++i)
+ /*empty*/;
+
+ // We found the end of the list or a statement. Scan for another declstmt.
+ for (; i != NumElts && !isa<DeclStmt>(Elts[i]); ++i)
+ /*empty*/;
+
+ if (i != NumElts) {
+ Decl *D = *cast<DeclStmt>(Elts[i])->decl_begin();
+ Diag(D->getLocation(), diag::ext_mixed_decls_code);
+ }
+ }
+ // Warn about unused expressions in statements.
+ for (unsigned i = 0; i != NumElts; ++i) {
+ // Ignore statements that are last in a statement expression.
+ if (isStmtExpr && i == NumElts - 1)
+ continue;
+
+ DiagnoseUnusedExprResult(Elts[i]);
+ }
+
+ return Owned(new (Context) CompoundStmt(Context, Elts, NumElts, L, R));
+}
+
+Action::OwningStmtResult
+Sema::ActOnCaseStmt(SourceLocation CaseLoc, ExprArg lhsval,
+ SourceLocation DotDotDotLoc, ExprArg rhsval,
+ SourceLocation ColonLoc) {
+ assert((lhsval.get() != 0) && "missing expression in case statement");
+
+ // C99 6.8.4.2p3: The expression shall be an integer constant.
+ // However, GCC allows any evaluatable integer expression.
+ Expr *LHSVal = static_cast<Expr*>(lhsval.get());
+ if (!LHSVal->isTypeDependent() && !LHSVal->isValueDependent() &&
+ VerifyIntegerConstantExpression(LHSVal))
+ return StmtError();
+
+ // GCC extension: The expression shall be an integer constant.
+
+ Expr *RHSVal = static_cast<Expr*>(rhsval.get());
+ if (RHSVal && !RHSVal->isTypeDependent() && !RHSVal->isValueDependent() &&
+ VerifyIntegerConstantExpression(RHSVal)) {
+ RHSVal = 0; // Recover by just forgetting about it.
+ rhsval = 0;
+ }
+
+ if (getSwitchStack().empty()) {
+ Diag(CaseLoc, diag::err_case_not_in_switch);
+ return StmtError();
+ }
+
+ // Only now release the smart pointers.
+ lhsval.release();
+ rhsval.release();
+ CaseStmt *CS = new (Context) CaseStmt(LHSVal, RHSVal, CaseLoc, DotDotDotLoc,
+ ColonLoc);
+ getSwitchStack().back()->addSwitchCase(CS);
+ return Owned(CS);
+}
+
+/// ActOnCaseStmtBody - This installs a statement as the body of a case.
+void Sema::ActOnCaseStmtBody(StmtTy *caseStmt, StmtArg subStmt) {
+ CaseStmt *CS = static_cast<CaseStmt*>(caseStmt);
+ Stmt *SubStmt = subStmt.takeAs<Stmt>();
+ CS->setSubStmt(SubStmt);
+}
+
+Action::OwningStmtResult
+Sema::ActOnDefaultStmt(SourceLocation DefaultLoc, SourceLocation ColonLoc,
+ StmtArg subStmt, Scope *CurScope) {
+ Stmt *SubStmt = subStmt.takeAs<Stmt>();
+
+ if (getSwitchStack().empty()) {
+ Diag(DefaultLoc, diag::err_default_not_in_switch);
+ return Owned(SubStmt);
+ }
+
+ DefaultStmt *DS = new (Context) DefaultStmt(DefaultLoc, ColonLoc, SubStmt);
+ getSwitchStack().back()->addSwitchCase(DS);
+ return Owned(DS);
+}
+
+Action::OwningStmtResult
+Sema::ActOnLabelStmt(SourceLocation IdentLoc, IdentifierInfo *II,
+ SourceLocation ColonLoc, StmtArg subStmt) {
+ Stmt *SubStmt = subStmt.takeAs<Stmt>();
+ // Look up the record for this label identifier.
+ LabelStmt *&LabelDecl = getLabelMap()[II];
+
+ // If not forward referenced or defined already, just create a new LabelStmt.
+ if (LabelDecl == 0)
+ return Owned(LabelDecl = new (Context) LabelStmt(IdentLoc, II, SubStmt));
+
+ assert(LabelDecl->getID() == II && "Label mismatch!");
+
+ // Otherwise, this label was either forward reference or multiply defined. If
+ // multiply defined, reject it now.
+ if (LabelDecl->getSubStmt()) {
+ Diag(IdentLoc, diag::err_redefinition_of_label) << LabelDecl->getID();
+ Diag(LabelDecl->getIdentLoc(), diag::note_previous_definition);
+ return Owned(SubStmt);
+ }
+
+ // Otherwise, this label was forward declared, and we just found its real
+ // definition. Fill in the forward definition and return it.
+ LabelDecl->setIdentLoc(IdentLoc);
+ LabelDecl->setSubStmt(SubStmt);
+ return Owned(LabelDecl);
+}
+
+Action::OwningStmtResult
+Sema::ActOnIfStmt(SourceLocation IfLoc, FullExprArg CondVal, DeclPtrTy CondVar,
+ StmtArg ThenVal, SourceLocation ElseLoc,
+ StmtArg ElseVal) {
+ OwningExprResult CondResult(CondVal.release());
+
+ VarDecl *ConditionVar = 0;
+ if (CondVar.get()) {
+ ConditionVar = CondVar.getAs<VarDecl>();
+ CondResult = CheckConditionVariable(ConditionVar);
+ if (CondResult.isInvalid())
+ return StmtError();
+ }
+ Expr *ConditionExpr = CondResult.takeAs<Expr>();
+ if (!ConditionExpr)
+ return StmtError();
+
+ if (CheckBooleanCondition(ConditionExpr, IfLoc)) {
+ CondResult = ConditionExpr;
+ return StmtError();
+ }
+
+ Stmt *thenStmt = ThenVal.takeAs<Stmt>();
+ DiagnoseUnusedExprResult(thenStmt);
+
+ // Warn if the if block has a null body without an else value.
+ // this helps prevent bugs due to typos, such as
+ // if (condition);
+ // do_stuff();
+ if (!ElseVal.get()) {
+ if (NullStmt* stmt = dyn_cast<NullStmt>(thenStmt))
+ Diag(stmt->getSemiLoc(), diag::warn_empty_if_body);
+ }
+
+ Stmt *elseStmt = ElseVal.takeAs<Stmt>();
+ DiagnoseUnusedExprResult(elseStmt);
+
+ CondResult.release();
+ return Owned(new (Context) IfStmt(IfLoc, ConditionVar, ConditionExpr,
+ thenStmt, ElseLoc, elseStmt));
+}
+
+Action::OwningStmtResult
+Sema::ActOnStartOfSwitchStmt(FullExprArg cond, DeclPtrTy CondVar) {
+ OwningExprResult CondResult(cond.release());
+
+ VarDecl *ConditionVar = 0;
+ if (CondVar.get()) {
+ ConditionVar = CondVar.getAs<VarDecl>();
+ CondResult = CheckConditionVariable(ConditionVar);
+ if (CondResult.isInvalid())
+ return StmtError();
+ }
+ SwitchStmt *SS = new (Context) SwitchStmt(ConditionVar,
+ CondResult.takeAs<Expr>());
+ getSwitchStack().push_back(SS);
+ return Owned(SS);
+}
+
+/// ConvertIntegerToTypeWarnOnOverflow - Convert the specified APInt to have
+/// the specified width and sign. If an overflow occurs, detect it and emit
+/// the specified diagnostic.
+void Sema::ConvertIntegerToTypeWarnOnOverflow(llvm::APSInt &Val,
+ unsigned NewWidth, bool NewSign,
+ SourceLocation Loc,
+ unsigned DiagID) {
+ // Perform a conversion to the promoted condition type if needed.
+ if (NewWidth > Val.getBitWidth()) {
+ // If this is an extension, just do it.
+ llvm::APSInt OldVal(Val);
+ Val.extend(NewWidth);
+
+ // If the input was signed and negative and the output is unsigned,
+ // warn.
+ if (!NewSign && OldVal.isSigned() && OldVal.isNegative())
+ Diag(Loc, DiagID) << OldVal.toString(10) << Val.toString(10);
+
+ Val.setIsSigned(NewSign);
+ } else if (NewWidth < Val.getBitWidth()) {
+ // If this is a truncation, check for overflow.
+ llvm::APSInt ConvVal(Val);
+ ConvVal.trunc(NewWidth);
+ ConvVal.setIsSigned(NewSign);
+ ConvVal.extend(Val.getBitWidth());
+ ConvVal.setIsSigned(Val.isSigned());
+ if (ConvVal != Val)
+ Diag(Loc, DiagID) << Val.toString(10) << ConvVal.toString(10);
+
+ // Regardless of whether a diagnostic was emitted, really do the
+ // truncation.
+ Val.trunc(NewWidth);
+ Val.setIsSigned(NewSign);
+ } else if (NewSign != Val.isSigned()) {
+ // Convert the sign to match the sign of the condition. This can cause
+ // overflow as well: unsigned(INTMIN)
+ llvm::APSInt OldVal(Val);
+ Val.setIsSigned(NewSign);
+
+ if (Val.isNegative()) // Sign bit changes meaning.
+ Diag(Loc, DiagID) << OldVal.toString(10) << Val.toString(10);
+ }
+}
+
+namespace {
+ struct CaseCompareFunctor {
+ bool operator()(const std::pair<llvm::APSInt, CaseStmt*> &LHS,
+ const llvm::APSInt &RHS) {
+ return LHS.first < RHS;
+ }
+ bool operator()(const std::pair<llvm::APSInt, CaseStmt*> &LHS,
+ const std::pair<llvm::APSInt, CaseStmt*> &RHS) {
+ return LHS.first < RHS.first;
+ }
+ bool operator()(const llvm::APSInt &LHS,
+ const std::pair<llvm::APSInt, CaseStmt*> &RHS) {
+ return LHS < RHS.first;
+ }
+ };
+}
+
+/// CmpCaseVals - Comparison predicate for sorting case values.
+///
+static bool CmpCaseVals(const std::pair<llvm::APSInt, CaseStmt*>& lhs,
+ const std::pair<llvm::APSInt, CaseStmt*>& rhs) {
+ if (lhs.first < rhs.first)
+ return true;
+
+ if (lhs.first == rhs.first &&
+ lhs.second->getCaseLoc().getRawEncoding()
+ < rhs.second->getCaseLoc().getRawEncoding())
+ return true;
+ return false;
+}
+
+/// 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(const Expr* expr) {
+ const ImplicitCastExpr *ImplicitCast =
+ dyn_cast_or_null<ImplicitCastExpr>(expr);
+ if (ImplicitCast != NULL) {
+ const Expr *ExprBeforePromotion = ImplicitCast->getSubExpr();
+ QualType TypeBeforePromotion = ExprBeforePromotion->getType();
+ if (TypeBeforePromotion->isIntegralType()) {
+ return TypeBeforePromotion;
+ }
+ }
+ return expr->getType();
+}
+
+/// \brief Check (and possibly convert) the condition in a switch
+/// statement in C++.
+static bool CheckCXXSwitchCondition(Sema &S, SourceLocation SwitchLoc,
+ Expr *&CondExpr) {
+ if (CondExpr->isTypeDependent())
+ return false;
+
+ QualType CondType = CondExpr->getType();
+
+ // C++ 6.4.2.p2:
+ // The condition shall be of integral type, enumeration type, or of a class
+ // type for which a single conversion function to integral or enumeration
+ // type exists (12.3). If the condition is of class type, the condition is
+ // converted by calling that conversion function, and the result of the
+ // conversion is used in place of the original condition for the remainder
+ // of this section. Integral promotions are performed.
+
+ // Make sure that the condition expression has a complete type,
+ // otherwise we'll never find any conversions.
+ if (S.RequireCompleteType(SwitchLoc, CondType,
+ PDiag(diag::err_switch_incomplete_class_type)
+ << CondExpr->getSourceRange()))
+ return true;
+
+ llvm::SmallVector<CXXConversionDecl *, 4> ViableConversions;
+ llvm::SmallVector<CXXConversionDecl *, 4> ExplicitConversions;
+ if (const RecordType *RecordTy = CondType->getAs<RecordType>()) {
+ const UnresolvedSetImpl *Conversions
+ = cast<CXXRecordDecl>(RecordTy->getDecl())
+ ->getVisibleConversionFunctions();
+ for (UnresolvedSetImpl::iterator I = Conversions->begin(),
+ E = Conversions->end(); I != E; ++I) {
+ if (CXXConversionDecl *Conversion = dyn_cast<CXXConversionDecl>(*I))
+ if (Conversion->getConversionType().getNonReferenceType()
+ ->isIntegralType()) {
+ if (Conversion->isExplicit())
+ ExplicitConversions.push_back(Conversion);
+ else
+ ViableConversions.push_back(Conversion);
+ }
+ }
+
+ switch (ViableConversions.size()) {
+ case 0:
+ if (ExplicitConversions.size() == 1) {
+ // The user probably meant to invoke the given explicit
+ // conversion; use it.
+ QualType ConvTy
+ = ExplicitConversions[0]->getConversionType()
+ .getNonReferenceType();
+ std::string TypeStr;
+ ConvTy.getAsStringInternal(TypeStr, S.Context.PrintingPolicy);
+
+ S.Diag(SwitchLoc, diag::err_switch_explicit_conversion)
+ << CondType << ConvTy << CondExpr->getSourceRange()
+ << CodeModificationHint::CreateInsertion(CondExpr->getLocStart(),
+ "static_cast<" + TypeStr + ">(")
+ << CodeModificationHint::CreateInsertion(
+ S.PP.getLocForEndOfToken(CondExpr->getLocEnd()),
+ ")");
+ S.Diag(ExplicitConversions[0]->getLocation(),
+ diag::note_switch_conversion)
+ << ConvTy->isEnumeralType() << ConvTy;
+
+ // If we aren't in a SFINAE context, build a call to the
+ // explicit conversion function.
+ if (S.isSFINAEContext())
+ return true;
+
+ CondExpr = S.BuildCXXMemberCallExpr(CondExpr, ExplicitConversions[0]);
+ }
+
+ // We'll complain below about a non-integral condition type.
+ break;
+
+ case 1:
+ // Apply this conversion.
+ CondExpr = S.BuildCXXMemberCallExpr(CondExpr, ViableConversions[0]);
+ break;
+
+ default:
+ S.Diag(SwitchLoc, diag::err_switch_multiple_conversions)
+ << CondType << CondExpr->getSourceRange();
+ for (unsigned I = 0, N = ViableConversions.size(); I != N; ++I) {
+ QualType ConvTy
+ = ViableConversions[I]->getConversionType().getNonReferenceType();
+ S.Diag(ViableConversions[I]->getLocation(),
+ diag::note_switch_conversion)
+ << ConvTy->isEnumeralType() << ConvTy;
+ }
+ return true;
+ }
+ }
+
+ return false;
+}
+
+/// ActOnSwitchBodyError - This is called if there is an error parsing the
+/// body of the switch stmt instead of ActOnFinishSwitchStmt.
+void Sema::ActOnSwitchBodyError(SourceLocation SwitchLoc, StmtArg Switch,
+ StmtArg Body) {
+ // Keep the switch stack balanced.
+ assert(getSwitchStack().back() == (SwitchStmt*)Switch.get() &&
+ "switch stack missing push/pop!");
+ getSwitchStack().pop_back();
+}
+
+Action::OwningStmtResult
+Sema::ActOnFinishSwitchStmt(SourceLocation SwitchLoc, StmtArg Switch,
+ StmtArg Body) {
+ Stmt *BodyStmt = Body.takeAs<Stmt>();
+
+ SwitchStmt *SS = getSwitchStack().back();
+ assert(SS == (SwitchStmt*)Switch.get() && "switch stack missing push/pop!");
+
+ SS->setBody(BodyStmt, SwitchLoc);
+ getSwitchStack().pop_back();
+
+ if (SS->getCond() == 0) {
+ SS->Destroy(Context);
+ return StmtError();
+ }
+
+ Expr *CondExpr = SS->getCond();
+ QualType CondTypeBeforePromotion =
+ GetTypeBeforeIntegralPromotion(CondExpr);
+
+ if (getLangOptions().CPlusPlus &&
+ CheckCXXSwitchCondition(*this, SwitchLoc, CondExpr))
+ return StmtError();
+
+ // C99 6.8.4.2p5 - Integer promotions are performed on the controlling expr.
+ UsualUnaryConversions(CondExpr);
+ QualType CondType = CondExpr->getType();
+ SS->setCond(CondExpr);
+
+ // C++ 6.4.2.p2:
+ // Integral promotions are performed (on the switch condition).
+ //
+ // A case value unrepresentable by the original switch condition
+ // type (before the promotion) doesn't make sense, even when it can
+ // be represented by the promoted type. Therefore we need to find
+ // the pre-promotion type of the switch condition.
+ if (!CondExpr->isTypeDependent()) {
+ if (!CondType->isIntegerType()) { // C99 6.8.4.2p1
+ Diag(SwitchLoc, diag::err_typecheck_statement_requires_integer)
+ << CondType << CondExpr->getSourceRange();
+ return StmtError();
+ }
+
+ if (CondTypeBeforePromotion->isBooleanType()) {
+ // switch(bool_expr) {...} is often a programmer error, e.g.
+ // switch(n && mask) { ... } // Doh - should be "n & mask".
+ // One can always use an if statement instead of switch(bool_expr).
+ Diag(SwitchLoc, diag::warn_bool_switch_condition)
+ << CondExpr->getSourceRange();
+ }
+ }
+
+ // Get the bitwidth of the switched-on value before promotions. We must
+ // convert the integer case values to this width before comparison.
+ bool HasDependentValue
+ = CondExpr->isTypeDependent() || CondExpr->isValueDependent();
+ unsigned CondWidth
+ = HasDependentValue? 0
+ : static_cast<unsigned>(Context.getTypeSize(CondTypeBeforePromotion));
+ bool CondIsSigned = CondTypeBeforePromotion->isSignedIntegerType();
+
+ // Accumulate all of the case values in a vector so that we can sort them
+ // and detect duplicates. This vector contains the APInt for the case after
+ // it has been converted to the condition type.
+ typedef llvm::SmallVector<std::pair<llvm::APSInt, CaseStmt*>, 64> CaseValsTy;
+ CaseValsTy CaseVals;
+
+ // Keep track of any GNU case ranges we see. The APSInt is the low value.
+ 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->EvaluateAsInt(Context);
+
+ // Convert the value to the same width/sign as the condition.
+ ConvertIntegerToTypeWarnOnOverflow(LoVal, CondWidth, CondIsSigned,
+ CS->getLHS()->getLocStart(),
+ diag::warn_case_value_overflow);
+
+ // If the LHS is not the same type as the condition, insert an implicit
+ // cast.
+ ImpCastExprToType(Lo, CondType, CastExpr::CK_IntegralCast);
+ CS->setLHS(Lo);
+
+ // If this is a case range, remember it in CaseRanges, otherwise CaseVals.
+ if (CS->getRHS()) {
+ if (CS->getRHS()->isTypeDependent() ||
+ CS->getRHS()->isValueDependent()) {
+ HasDependentValue = true;
+ break;
+ }
+ CaseRanges.push_back(std::make_pair(LoVal, CS));
+ } else
+ CaseVals.push_back(std::make_pair(LoVal, CS));
+ }
+ }
+
+ if (!HasDependentValue) {
+ // Sort all the scalar case values so we can easily detect duplicates.
+ std::stable_sort(CaseVals.begin(), CaseVals.end(), CmpCaseVals);
+
+ if (!CaseVals.empty()) {
+ for (unsigned i = 0, e = CaseVals.size()-1; i != e; ++i) {
+ if (CaseVals[i].first == CaseVals[i+1].first) {
+ // If we have a duplicate, report it.
+ Diag(CaseVals[i+1].second->getLHS()->getLocStart(),
+ diag::err_duplicate_case) << CaseVals[i].first.toString(10);
+ Diag(CaseVals[i].second->getLHS()->getLocStart(),
+ diag::note_duplicate_case_prev);
+ // FIXME: We really want to remove the bogus case stmt from the
+ // substmt, but we have no way to do this right now.
+ CaseListIsErroneous = true;
+ }
+ }
+ }
+
+ // Detect duplicate case ranges, which usually don't exist at all in
+ // the first place.
+ if (!CaseRanges.empty()) {
+ // Sort all the case ranges by their low value so we can easily detect
+ // overlaps between ranges.
+ std::stable_sort(CaseRanges.begin(), CaseRanges.end());
+
+ // Scan the ranges, computing the high values and removing empty ranges.
+ std::vector<llvm::APSInt> HiVals;
+ for (unsigned i = 0, e = CaseRanges.size(); i != e; ++i) {
+ CaseStmt *CR = CaseRanges[i].second;
+ Expr *Hi = CR->getRHS();
+ llvm::APSInt HiVal = Hi->EvaluateAsInt(Context);
+
+ // Convert the value to the same width/sign as the condition.
+ ConvertIntegerToTypeWarnOnOverflow(HiVal, CondWidth, CondIsSigned,
+ CR->getRHS()->getLocStart(),
+ diag::warn_case_value_overflow);
+
+ // If the LHS is not the same type as the condition, insert an implicit
+ // cast.
+ ImpCastExprToType(Hi, CondType, CastExpr::CK_IntegralCast);
+ CR->setRHS(Hi);
+
+ // If the low value is bigger than the high value, the case is empty.
+ if (CaseRanges[i].first > HiVal) {
+ Diag(CR->getLHS()->getLocStart(), diag::warn_case_empty_range)
+ << SourceRange(CR->getLHS()->getLocStart(),
+ CR->getRHS()->getLocEnd());
+ CaseRanges.erase(CaseRanges.begin()+i);
+ --i, --e;
+ continue;
+ }
+ HiVals.push_back(HiVal);
+ }
+
+ // Rescan the ranges, looking for overlap with singleton values and other
+ // ranges. Since the range list is sorted, we only need to compare case
+ // ranges with their neighbors.
+ for (unsigned i = 0, e = CaseRanges.size(); i != e; ++i) {
+ llvm::APSInt &CRLo = CaseRanges[i].first;
+ llvm::APSInt &CRHi = HiVals[i];
+ CaseStmt *CR = CaseRanges[i].second;
+
+ // Check to see whether the case range overlaps with any
+ // singleton cases.
+ CaseStmt *OverlapStmt = 0;
+ llvm::APSInt OverlapVal(32);
+
+ // Find the smallest value >= the lower bound. If I is in the
+ // case range, then we have overlap.
+ CaseValsTy::iterator I = std::lower_bound(CaseVals.begin(),
+ CaseVals.end(), CRLo,
+ CaseCompareFunctor());
+ if (I != CaseVals.end() && I->first < CRHi) {
+ OverlapVal = I->first; // Found overlap with scalar.
+ OverlapStmt = I->second;
+ }
+
+ // Find the smallest value bigger than the upper bound.
+ I = std::upper_bound(I, CaseVals.end(), CRHi, CaseCompareFunctor());
+ if (I != CaseVals.begin() && (I-1)->first >= CRLo) {
+ OverlapVal = (I-1)->first; // Found overlap with scalar.
+ OverlapStmt = (I-1)->second;
+ }
+
+ // Check to see if this case stmt overlaps with the subsequent
+ // case range.
+ if (i && CRLo <= HiVals[i-1]) {
+ OverlapVal = HiVals[i-1]; // Found overlap with range.
+ OverlapStmt = CaseRanges[i-1].second;
+ }
+
+ if (OverlapStmt) {
+ // If we have a duplicate, report it.
+ Diag(CR->getLHS()->getLocStart(), diag::err_duplicate_case)
+ << OverlapVal.toString(10);
+ Diag(OverlapStmt->getLHS()->getLocStart(),
+ diag::note_duplicate_case_prev);
+ // FIXME: We really want to remove the bogus case stmt from the
+ // substmt, but we have no way to do this right now.
+ CaseListIsErroneous = true;
+ }
+ }
+ }
+
+ // Check to see if switch is over an Enum and handles all of its
+ // values
+ const EnumType* ET = dyn_cast<EnumType>(CondTypeBeforePromotion);
+ // If switch has default case, then ignore it.
+ if (!CaseListIsErroneous && !TheDefaultStmt && ET) {
+ const EnumDecl *ED = ET->getDecl();
+ typedef llvm::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();
+ if(Val.getBitWidth() < CondWidth)
+ Val.extend(CondWidth);
+ Val.setIsSigned(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
+ 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::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::not_in_enum) << ED->getDeclName();
+ }
+
+ llvm::APSInt Hi = RI->second->getRHS()->EvaluateAsInt(Context);
+ while (EI != EIend && EI->first < Hi)
+ EI++;
+ if (EI == EIend || EI->first != Hi)
+ Diag(RI->second->getRHS()->getExprLoc(), diag::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();
+ EI = EnumVals.begin();
+ for (; 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()->EvaluateAsInt(Context);
+ if (EI->first <= Hi)
+ break;
+ }
+
+ if (RI == CaseRanges.end() || EI->first < RI->first)
+ Diag(CondExpr->getExprLoc(), diag::warn_missing_cases) << EI->second->getDeclName();
+ }
+ }
+ }
+
+ // FIXME: If the case list was broken is some way, we don't have a good system
+ // to patch it up. Instead, just return the whole substmt as broken.
+ if (CaseListIsErroneous)
+ return StmtError();
+
+ Switch.release();
+ return Owned(SS);
+}
+
+Action::OwningStmtResult
+Sema::ActOnWhileStmt(SourceLocation WhileLoc, FullExprArg Cond,
+ DeclPtrTy CondVar, StmtArg Body) {
+ OwningExprResult CondResult(Cond.release());
+
+ VarDecl *ConditionVar = 0;
+ if (CondVar.get()) {
+ ConditionVar = CondVar.getAs<VarDecl>();
+ CondResult = CheckConditionVariable(ConditionVar);
+ if (CondResult.isInvalid())
+ return StmtError();
+ }
+ Expr *ConditionExpr = CondResult.takeAs<Expr>();
+ if (!ConditionExpr)
+ return StmtError();
+
+ if (CheckBooleanCondition(ConditionExpr, WhileLoc)) {
+ CondResult = ConditionExpr;
+ return StmtError();
+ }
+
+ Stmt *bodyStmt = Body.takeAs<Stmt>();
+ DiagnoseUnusedExprResult(bodyStmt);
+
+ CondResult.release();
+ return Owned(new (Context) WhileStmt(ConditionVar, ConditionExpr, bodyStmt,
+ WhileLoc));
+}
+
+Action::OwningStmtResult
+Sema::ActOnDoStmt(SourceLocation DoLoc, StmtArg Body,
+ SourceLocation WhileLoc, SourceLocation CondLParen,
+ ExprArg Cond, SourceLocation CondRParen) {
+ Expr *condExpr = Cond.takeAs<Expr>();
+ assert(condExpr && "ActOnDoStmt(): missing expression");
+
+ if (CheckBooleanCondition(condExpr, DoLoc)) {
+ Cond = condExpr;
+ return StmtError();
+ }
+
+ Stmt *bodyStmt = Body.takeAs<Stmt>();
+ DiagnoseUnusedExprResult(bodyStmt);
+
+ Cond.release();
+ return Owned(new (Context) DoStmt(bodyStmt, condExpr, DoLoc,
+ WhileLoc, CondRParen));
+}
+
+Action::OwningStmtResult
+Sema::ActOnForStmt(SourceLocation ForLoc, SourceLocation LParenLoc,
+ StmtArg first, FullExprArg second, DeclPtrTy secondVar,
+ FullExprArg third,
+ SourceLocation RParenLoc, StmtArg body) {
+ Stmt *First = static_cast<Stmt*>(first.get());
+
+ if (!getLangOptions().CPlusPlus) {
+ if (DeclStmt *DS = dyn_cast_or_null<DeclStmt>(First)) {
+ // C99 6.8.5p3: The declaration part of a 'for' statement shall only
+ // declare identifiers for objects having storage class 'auto' or
+ // 'register'.
+ for (DeclStmt::decl_iterator DI=DS->decl_begin(), DE=DS->decl_end();
+ DI!=DE; ++DI) {
+ VarDecl *VD = dyn_cast<VarDecl>(*DI);
+ if (VD && VD->isBlockVarDecl() && !VD->hasLocalStorage())
+ VD = 0;
+ if (VD == 0)
+ Diag((*DI)->getLocation(), diag::err_non_variable_decl_in_for);
+ // FIXME: mark decl erroneous!
+ }
+ }
+ }
+
+ OwningExprResult SecondResult(second.release());
+ VarDecl *ConditionVar = 0;
+ if (secondVar.get()) {
+ ConditionVar = secondVar.getAs<VarDecl>();
+ SecondResult = CheckConditionVariable(ConditionVar);
+ if (SecondResult.isInvalid())
+ return StmtError();
+ }
+
+ Expr *Second = SecondResult.takeAs<Expr>();
+ if (Second && CheckBooleanCondition(Second, ForLoc)) {
+ SecondResult = Second;
+ return StmtError();
+ }
+
+ Expr *Third = third.release().takeAs<Expr>();
+ Stmt *Body = static_cast<Stmt*>(body.get());
+
+ DiagnoseUnusedExprResult(First);
+ DiagnoseUnusedExprResult(Third);
+ DiagnoseUnusedExprResult(Body);
+
+ first.release();
+ body.release();
+ return Owned(new (Context) ForStmt(First, Second, ConditionVar, Third, Body,
+ ForLoc, LParenLoc, RParenLoc));
+}
+
+Action::OwningStmtResult
+Sema::ActOnObjCForCollectionStmt(SourceLocation ForLoc,
+ SourceLocation LParenLoc,
+ StmtArg first, ExprArg second,
+ SourceLocation RParenLoc, StmtArg body) {
+ Stmt *First = static_cast<Stmt*>(first.get());
+ Expr *Second = static_cast<Expr*>(second.get());
+ Stmt *Body = static_cast<Stmt*>(body.get());
+ if (First) {
+ QualType FirstType;
+ if (DeclStmt *DS = dyn_cast<DeclStmt>(First)) {
+ if (!DS->isSingleDecl())
+ return StmtError(Diag((*DS->decl_begin())->getLocation(),
+ diag::err_toomany_element_decls));
+
+ Decl *D = DS->getSingleDecl();
+ FirstType = cast<ValueDecl>(D)->getType();
+ // C99 6.8.5p3: The declaration part of a 'for' statement shall only
+ // declare identifiers for objects having storage class 'auto' or
+ // 'register'.
+ VarDecl *VD = cast<VarDecl>(D);
+ if (VD->isBlockVarDecl() && !VD->hasLocalStorage())
+ return StmtError(Diag(VD->getLocation(),
+ diag::err_non_variable_decl_in_for));
+ } else {
+ if (cast<Expr>(First)->isLvalue(Context) != Expr::LV_Valid)
+ return StmtError(Diag(First->getLocStart(),
+ diag::err_selector_element_not_lvalue)
+ << First->getSourceRange());
+
+ FirstType = static_cast<Expr*>(First)->getType();
+ }
+ if (!FirstType->isObjCObjectPointerType() &&
+ !FirstType->isBlockPointerType())
+ Diag(ForLoc, diag::err_selector_element_type)
+ << FirstType << First->getSourceRange();
+ }
+ if (Second) {
+ DefaultFunctionArrayLvalueConversion(Second);
+ QualType SecondType = Second->getType();
+ if (!SecondType->isObjCObjectPointerType())
+ Diag(ForLoc, diag::err_collection_expr_type)
+ << SecondType << Second->getSourceRange();
+ }
+ first.release();
+ second.release();
+ body.release();
+ return Owned(new (Context) ObjCForCollectionStmt(First, Second, Body,
+ ForLoc, RParenLoc));
+}
+
+Action::OwningStmtResult
+Sema::ActOnGotoStmt(SourceLocation GotoLoc, SourceLocation LabelLoc,
+ IdentifierInfo *LabelII) {
+ // Look up the record for this label identifier.
+ LabelStmt *&LabelDecl = getLabelMap()[LabelII];
+
+ // If we haven't seen this label yet, create a forward reference.
+ if (LabelDecl == 0)
+ LabelDecl = new (Context) LabelStmt(LabelLoc, LabelII, 0);
+
+ return Owned(new (Context) GotoStmt(LabelDecl, GotoLoc, LabelLoc));
+}
+
+Action::OwningStmtResult
+Sema::ActOnIndirectGotoStmt(SourceLocation GotoLoc, SourceLocation StarLoc,
+ ExprArg DestExp) {
+ // Convert operand to void*
+ Expr* E = DestExp.takeAs<Expr>();
+ if (!E->isTypeDependent()) {
+ QualType ETy = E->getType();
+ QualType DestTy = Context.getPointerType(Context.VoidTy.withConst());
+ AssignConvertType ConvTy =
+ CheckSingleAssignmentConstraints(DestTy, E);
+ if (DiagnoseAssignmentResult(ConvTy, StarLoc, DestTy, ETy, E, AA_Passing))
+ return StmtError();
+ }
+ return Owned(new (Context) IndirectGotoStmt(GotoLoc, StarLoc, E));
+}
+
+Action::OwningStmtResult
+Sema::ActOnContinueStmt(SourceLocation ContinueLoc, Scope *CurScope) {
+ Scope *S = CurScope->getContinueParent();
+ if (!S) {
+ // C99 6.8.6.2p1: A break shall appear only in or as a loop body.
+ return StmtError(Diag(ContinueLoc, diag::err_continue_not_in_loop));
+ }
+
+ return Owned(new (Context) ContinueStmt(ContinueLoc));
+}
+
+Action::OwningStmtResult
+Sema::ActOnBreakStmt(SourceLocation BreakLoc, Scope *CurScope) {
+ Scope *S = CurScope->getBreakParent();
+ if (!S) {
+ // C99 6.8.6.3p1: A break shall appear only in or as a switch/loop body.
+ return StmtError(Diag(BreakLoc, diag::err_break_not_in_loop_or_switch));
+ }
+
+ return Owned(new (Context) BreakStmt(BreakLoc));
+}
+
+/// ActOnBlockReturnStmt - Utility routine to figure out block's return type.
+///
+Action::OwningStmtResult
+Sema::ActOnBlockReturnStmt(SourceLocation ReturnLoc, Expr *RetValExp) {
+ // If this is the first return we've seen in the block, infer the type of
+ // the block from it.
+ if (CurBlock->ReturnType.isNull()) {
+ if (RetValExp) {
+ // Don't call UsualUnaryConversions(), since we don't want to do
+ // integer promotions here.
+ DefaultFunctionArrayLvalueConversion(RetValExp);
+ CurBlock->ReturnType = RetValExp->getType();
+ if (BlockDeclRefExpr *CDRE = dyn_cast<BlockDeclRefExpr>(RetValExp)) {
+ // We have to remove a 'const' added to copied-in variable which was
+ // part of the implementation spec. and not the actual qualifier for
+ // the variable.
+ if (CDRE->isConstQualAdded())
+ CurBlock->ReturnType.removeConst();
+ }
+ } else
+ CurBlock->ReturnType = Context.VoidTy;
+ }
+ QualType FnRetType = CurBlock->ReturnType;
+
+ if (CurBlock->TheDecl->hasAttr<NoReturnAttr>()) {
+ Diag(ReturnLoc, diag::err_noreturn_block_has_return_expr)
+ << getCurFunctionOrMethodDecl()->getDeclName();
+ return StmtError();
+ }
+
+ // Otherwise, verify that this result type matches the previous one. We are
+ // pickier with blocks than for normal functions because we don't have GCC
+ // compatibility to worry about here.
+ if (CurBlock->ReturnType->isVoidType()) {
+ if (RetValExp) {
+ Diag(ReturnLoc, diag::err_return_block_has_expr);
+ RetValExp->Destroy(Context);
+ RetValExp = 0;
+ }
+ return Owned(new (Context) ReturnStmt(ReturnLoc, RetValExp));
+ }
+
+ if (!RetValExp)
+ return StmtError(Diag(ReturnLoc, diag::err_block_return_missing_expr));
+
+ if (!FnRetType->isDependentType() && !RetValExp->isTypeDependent()) {
+ // we have a non-void block with an expression, continue checking
+
+ // C99 6.8.6.4p3(136): The return statement is not an assignment. The
+ // overlap restriction of subclause 6.5.16.1 does not apply to the case of
+ // function return.
+
+ // In C++ the return statement is handled via a copy initialization.
+ // the C version of which boils down to CheckSingleAssignmentConstraints.
+ OwningExprResult Res = PerformCopyInitialization(
+ InitializedEntity::InitializeResult(ReturnLoc,
+ FnRetType),
+ SourceLocation(),
+ Owned(RetValExp));
+ if (Res.isInvalid()) {
+ // FIXME: Cleanup temporaries here, anyway?
+ return StmtError();
+ }
+
+ RetValExp = Res.takeAs<Expr>();
+ if (RetValExp)
+ CheckReturnStackAddr(RetValExp, FnRetType, ReturnLoc);
+ }
+
+ return Owned(new (Context) ReturnStmt(ReturnLoc, RetValExp));
+}
+
+/// IsReturnCopyElidable - Whether returning @p RetExpr from a function that
+/// returns a @p RetType fulfills the criteria for copy elision (C++0x 12.8p15).
+static bool IsReturnCopyElidable(ASTContext &Ctx, QualType RetType,
+ Expr *RetExpr) {
+ QualType ExprType = RetExpr->getType();
+ // - in a return statement in a function with ...
+ // ... a class return type ...
+ if (!RetType->isRecordType())
+ return false;
+ // ... the same cv-unqualified type as the function return type ...
+ if (!Ctx.hasSameUnqualifiedType(RetType, ExprType))
+ return false;
+ // ... the expression is the name of a non-volatile automatic object ...
+ // We ignore parentheses here.
+ // FIXME: Is this compliant?
+ const DeclRefExpr *DR = dyn_cast<DeclRefExpr>(RetExpr->IgnoreParens());
+ if (!DR)
+ return false;
+ const VarDecl *VD = dyn_cast<VarDecl>(DR->getDecl());
+ if (!VD)
+ return false;
+ return VD->hasLocalStorage() && !VD->getType()->isReferenceType()
+ && !VD->getType().isVolatileQualified();
+}
+
+Action::OwningStmtResult
+Sema::ActOnReturnStmt(SourceLocation ReturnLoc, ExprArg rex) {
+ Expr *RetValExp = rex.takeAs<Expr>();
+ if (CurBlock)
+ return ActOnBlockReturnStmt(ReturnLoc, RetValExp);
+
+ QualType FnRetType;
+ if (const FunctionDecl *FD = getCurFunctionDecl()) {
+ FnRetType = FD->getResultType();
+ if (FD->hasAttr<NoReturnAttr>() ||
+ FD->getType()->getAs<FunctionType>()->getNoReturnAttr())
+ Diag(ReturnLoc, diag::warn_noreturn_function_has_return_expr)
+ << getCurFunctionOrMethodDecl()->getDeclName();
+ } else if (ObjCMethodDecl *MD = getCurMethodDecl())
+ FnRetType = MD->getResultType();
+ else // If we don't have a function/method context, bail.
+ return StmtError();
+
+ if (FnRetType->isVoidType()) {
+ if (RetValExp && !RetValExp->isTypeDependent()) {
+ // C99 6.8.6.4p1 (ext_ since GCC warns)
+ unsigned D = diag::ext_return_has_expr;
+ if (RetValExp->getType()->isVoidType())
+ D = diag::ext_return_has_void_expr;
+
+ // return (some void expression); is legal in C++.
+ if (D != diag::ext_return_has_void_expr ||
+ !getLangOptions().CPlusPlus) {
+ NamedDecl *CurDecl = getCurFunctionOrMethodDecl();
+ Diag(ReturnLoc, D)
+ << CurDecl->getDeclName() << isa<ObjCMethodDecl>(CurDecl)
+ << RetValExp->getSourceRange();
+ }
+
+ RetValExp = MaybeCreateCXXExprWithTemporaries(RetValExp);
+ }
+ return Owned(new (Context) ReturnStmt(ReturnLoc, RetValExp));
+ }
+
+ if (!RetValExp && !FnRetType->isDependentType()) {
+ unsigned DiagID = diag::warn_return_missing_expr; // C90 6.6.6.4p4
+ // C99 6.8.6.4p1 (ext_ since GCC warns)
+ if (getLangOptions().C99) DiagID = diag::ext_return_missing_expr;
+
+ if (FunctionDecl *FD = getCurFunctionDecl())
+ Diag(ReturnLoc, DiagID) << FD->getIdentifier() << 0/*fn*/;
+ else
+ Diag(ReturnLoc, DiagID) << getCurMethodDecl()->getDeclName() << 1/*meth*/;
+ return Owned(new (Context) ReturnStmt(ReturnLoc, (Expr*)0));
+ }
+
+ if (!FnRetType->isDependentType() && !RetValExp->isTypeDependent()) {
+ // we have a non-void function with an expression, continue checking
+
+ // C99 6.8.6.4p3(136): The return statement is not an assignment. The
+ // overlap restriction of subclause 6.5.16.1 does not apply to the case of
+ // function return.
+
+ // C++0x 12.8p15: When certain criteria are met, an implementation is
+ // allowed to omit the copy construction of a class object, [...]
+ // - in a return statement in a function with a class return type, when
+ // the expression is the name of a non-volatile automatic object with
+ // the same cv-unqualified type as the function return type, the copy
+ // operation can be omitted [...]
+ // C++0x 12.8p16: When the criteria for elision of a copy operation are met
+ // and the object to be copied is designated by an lvalue, overload
+ // resolution to select the constructor for the copy is first performed
+ // as if the object were designated by an rvalue.
+ // Note that we only compute Elidable if we're in C++0x, since we don't
+ // care otherwise.
+ bool Elidable = getLangOptions().CPlusPlus0x ?
+ IsReturnCopyElidable(Context, FnRetType, RetValExp) :
+ false;
+ // FIXME: Elidable
+ (void)Elidable;
+
+ // In C++ the return statement is handled via a copy initialization.
+ // the C version of which boils down to CheckSingleAssignmentConstraints.
+ OwningExprResult Res = PerformCopyInitialization(
+ InitializedEntity::InitializeResult(ReturnLoc,
+ FnRetType),
+ SourceLocation(),
+ Owned(RetValExp));
+ if (Res.isInvalid()) {
+ // FIXME: Cleanup temporaries here, anyway?
+ return StmtError();
+ }
+
+ RetValExp = Res.takeAs<Expr>();
+ if (RetValExp)
+ CheckReturnStackAddr(RetValExp, FnRetType, ReturnLoc);
+ }
+
+ if (RetValExp)
+ RetValExp = MaybeCreateCXXExprWithTemporaries(RetValExp);
+ return Owned(new (Context) ReturnStmt(ReturnLoc, RetValExp));
+}
+
+/// CheckAsmLValue - GNU C has an extremely ugly extension whereby they silently
+/// ignore "noop" casts in places where an lvalue is required by an inline asm.
+/// We emulate this behavior when -fheinous-gnu-extensions is specified, but
+/// provide a strong guidance to not use it.
+///
+/// This method checks to see if the argument is an acceptable l-value and
+/// returns false if it is a case we can handle.
+static bool CheckAsmLValue(const Expr *E, Sema &S) {
+ // Type dependent expressions will be checked during instantiation.
+ if (E->isTypeDependent())
+ return false;
+
+ if (E->isLvalue(S.Context) == Expr::LV_Valid)
+ return false; // Cool, this is an lvalue.
+
+ // Okay, this is not an lvalue, but perhaps it is the result of a cast that we
+ // are supposed to allow.
+ const Expr *E2 = E->IgnoreParenNoopCasts(S.Context);
+ if (E != E2 && E2->isLvalue(S.Context) == Expr::LV_Valid) {
+ if (!S.getLangOptions().HeinousExtensions)
+ S.Diag(E2->getLocStart(), diag::err_invalid_asm_cast_lvalue)
+ << E->getSourceRange();
+ else
+ S.Diag(E2->getLocStart(), diag::warn_invalid_asm_cast_lvalue)
+ << E->getSourceRange();
+ // Accept, even if we emitted an error diagnostic.
+ return false;
+ }
+
+ // None of the above, just randomly invalid non-lvalue.
+ return true;
+}
+
+
+Sema::OwningStmtResult Sema::ActOnAsmStmt(SourceLocation AsmLoc,
+ bool IsSimple,
+ bool IsVolatile,
+ unsigned NumOutputs,
+ unsigned NumInputs,
+ IdentifierInfo **Names,
+ MultiExprArg constraints,
+ MultiExprArg exprs,
+ ExprArg asmString,
+ MultiExprArg clobbers,
+ SourceLocation RParenLoc,
+ bool MSAsm) {
+ unsigned NumClobbers = clobbers.size();
+ StringLiteral **Constraints =
+ reinterpret_cast<StringLiteral**>(constraints.get());
+ Expr **Exprs = reinterpret_cast<Expr **>(exprs.get());
+ StringLiteral *AsmString = cast<StringLiteral>((Expr *)asmString.get());
+ StringLiteral **Clobbers = reinterpret_cast<StringLiteral**>(clobbers.get());
+
+ llvm::SmallVector<TargetInfo::ConstraintInfo, 4> OutputConstraintInfos;
+
+ // The parser verifies that there is a string literal here.
+ if (AsmString->isWide())
+ return StmtError(Diag(AsmString->getLocStart(),diag::err_asm_wide_character)
+ << AsmString->getSourceRange());
+
+ for (unsigned i = 0; i != NumOutputs; i++) {
+ StringLiteral *Literal = Constraints[i];
+ if (Literal->isWide())
+ return StmtError(Diag(Literal->getLocStart(),diag::err_asm_wide_character)
+ << Literal->getSourceRange());
+
+ llvm::StringRef OutputName;
+ if (Names[i])
+ OutputName = Names[i]->getName();
+
+ TargetInfo::ConstraintInfo Info(Literal->getString(), OutputName);
+ if (!Context.Target.validateOutputConstraint(Info))
+ return StmtError(Diag(Literal->getLocStart(),
+ diag::err_asm_invalid_output_constraint)
+ << Info.getConstraintStr());
+
+ // Check that the output exprs are valid lvalues.
+ Expr *OutputExpr = Exprs[i];
+ if (CheckAsmLValue(OutputExpr, *this)) {
+ return StmtError(Diag(OutputExpr->getLocStart(),
+ diag::err_asm_invalid_lvalue_in_output)
+ << OutputExpr->getSourceRange());
+ }
+
+ OutputConstraintInfos.push_back(Info);
+ }
+
+ llvm::SmallVector<TargetInfo::ConstraintInfo, 4> InputConstraintInfos;
+
+ for (unsigned i = NumOutputs, e = NumOutputs + NumInputs; i != e; i++) {
+ StringLiteral *Literal = Constraints[i];
+ if (Literal->isWide())
+ return StmtError(Diag(Literal->getLocStart(),diag::err_asm_wide_character)
+ << Literal->getSourceRange());
+
+ llvm::StringRef InputName;
+ if (Names[i])
+ InputName = Names[i]->getName();
+
+ TargetInfo::ConstraintInfo Info(Literal->getString(), InputName);
+ if (!Context.Target.validateInputConstraint(OutputConstraintInfos.data(),
+ NumOutputs, Info)) {
+ return StmtError(Diag(Literal->getLocStart(),
+ diag::err_asm_invalid_input_constraint)
+ << Info.getConstraintStr());
+ }
+
+ Expr *InputExpr = Exprs[i];
+
+ // Only allow void types for memory constraints.
+ if (Info.allowsMemory() && !Info.allowsRegister()) {
+ if (CheckAsmLValue(InputExpr, *this))
+ return StmtError(Diag(InputExpr->getLocStart(),
+ diag::err_asm_invalid_lvalue_in_input)
+ << Info.getConstraintStr()
+ << InputExpr->getSourceRange());
+ }
+
+ if (Info.allowsRegister()) {
+ if (InputExpr->getType()->isVoidType()) {
+ return StmtError(Diag(InputExpr->getLocStart(),
+ diag::err_asm_invalid_type_in_input)
+ << InputExpr->getType() << Info.getConstraintStr()
+ << InputExpr->getSourceRange());
+ }
+ }
+
+ DefaultFunctionArrayLvalueConversion(Exprs[i]);
+
+ InputConstraintInfos.push_back(Info);
+ }
+
+ // Check that the clobbers are valid.
+ for (unsigned i = 0; i != NumClobbers; i++) {
+ StringLiteral *Literal = Clobbers[i];
+ if (Literal->isWide())
+ return StmtError(Diag(Literal->getLocStart(),diag::err_asm_wide_character)
+ << Literal->getSourceRange());
+
+ llvm::StringRef Clobber = Literal->getString();
+
+ if (!Context.Target.isValidGCCRegisterName(Clobber))
+ return StmtError(Diag(Literal->getLocStart(),
+ diag::err_asm_unknown_register_name) << Clobber);
+ }
+
+ constraints.release();
+ exprs.release();
+ asmString.release();
+ clobbers.release();
+ AsmStmt *NS =
+ new (Context) AsmStmt(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.
+ llvm::SmallVector<AsmStmt::AsmStringPiece, 8> Pieces;
+ unsigned DiagOffs;
+ if (unsigned DiagID = NS->AnalyzeAsmString(Pieces, Context, DiagOffs)) {
+ Diag(getLocationOfStringLiteralByte(AsmString, DiagOffs), DiagID)
+ << AsmString->getSourceRange();
+ DeleteStmt(NS);
+ return StmtError();
+ }
+
+ // Validate tied input operands for type mismatches.
+ for (unsigned i = 0, e = InputConstraintInfos.size(); i != e; ++i) {
+ TargetInfo::ConstraintInfo &Info = InputConstraintInfos[i];
+
+ // If this is a tied constraint, verify that the output and input have
+ // either exactly the same type, or that they are int/ptr operands with the
+ // same size (int/long, int*/long, are ok etc).
+ if (!Info.hasTiedOperand()) continue;
+
+ unsigned TiedTo = Info.getTiedOperand();
+ Expr *OutputExpr = Exprs[TiedTo];
+ Expr *InputExpr = Exprs[i+NumOutputs];
+ QualType InTy = InputExpr->getType();
+ QualType OutTy = OutputExpr->getType();
+ if (Context.hasSameType(InTy, OutTy))
+ continue; // All types can be tied to themselves.
+
+ // Int/ptr operands have some special cases that we allow.
+ if ((OutTy->isIntegerType() || OutTy->isPointerType()) &&
+ (InTy->isIntegerType() || InTy->isPointerType())) {
+
+ // They are ok if they are the same size. Tying void* to int is ok if
+ // they are the same size, for example. This also allows tying void* to
+ // int*.
+ uint64_t OutSize = Context.getTypeSize(OutTy);
+ uint64_t InSize = Context.getTypeSize(InTy);
+ if (OutSize == InSize)
+ continue;
+
+ // If the smaller input/output operand is not mentioned in the asm string,
+ // then we can promote it and the asm string won't notice. Check this
+ // case now.
+ bool SmallerValueMentioned = false;
+ for (unsigned p = 0, e = Pieces.size(); p != e; ++p) {
+ AsmStmt::AsmStringPiece &Piece = Pieces[p];
+ if (!Piece.isOperand()) continue;
+
+ // If this is a reference to the input and if the input was the smaller
+ // one, then we have to reject this asm.
+ if (Piece.getOperandNo() == i+NumOutputs) {
+ if (InSize < OutSize) {
+ SmallerValueMentioned = true;
+ break;
+ }
+ }
+
+ // If this is a reference to the input and if the input was the smaller
+ // one, then we have to reject this asm.
+ if (Piece.getOperandNo() == TiedTo) {
+ if (InSize > OutSize) {
+ SmallerValueMentioned = true;
+ break;
+ }
+ }
+ }
+
+ // If the smaller value wasn't mentioned in the asm string, and if the
+ // output was a register, just extend the shorter one to the size of the
+ // larger one.
+ if (!SmallerValueMentioned &&
+ OutputConstraintInfos[TiedTo].allowsRegister())
+ continue;
+ }
+
+ Diag(InputExpr->getLocStart(),
+ diag::err_asm_tying_incompatible_types)
+ << InTy << OutTy << OutputExpr->getSourceRange()
+ << InputExpr->getSourceRange();
+ DeleteStmt(NS);
+ return StmtError();
+ }
+
+ return Owned(NS);
+}
+
+Action::OwningStmtResult
+Sema::ActOnObjCAtCatchStmt(SourceLocation AtLoc,
+ SourceLocation RParen, DeclPtrTy Parm,
+ StmtArg Body, StmtArg catchList) {
+ Stmt *CatchList = catchList.takeAs<Stmt>();
+ ParmVarDecl *PVD = cast_or_null<ParmVarDecl>(Parm.getAs<Decl>());
+
+ // PVD == 0 implies @catch(...).
+ if (PVD) {
+ // If we already know the decl is invalid, reject it.
+ if (PVD->isInvalidDecl())
+ return StmtError();
+
+ if (!PVD->getType()->isObjCObjectPointerType())
+ return StmtError(Diag(PVD->getLocation(),
+ diag::err_catch_param_not_objc_type));
+ if (PVD->getType()->isObjCQualifiedIdType())
+ return StmtError(Diag(PVD->getLocation(),
+ diag::err_illegal_qualifiers_on_catch_parm));
+ }
+
+ ObjCAtCatchStmt *CS = new (Context) ObjCAtCatchStmt(AtLoc, RParen,
+ PVD, Body.takeAs<Stmt>(), CatchList);
+ return Owned(CatchList ? CatchList : CS);
+}
+
+Action::OwningStmtResult
+Sema::ActOnObjCAtFinallyStmt(SourceLocation AtLoc, StmtArg Body) {
+ return Owned(new (Context) ObjCAtFinallyStmt(AtLoc,
+ static_cast<Stmt*>(Body.release())));
+}
+
+Action::OwningStmtResult
+Sema::ActOnObjCAtTryStmt(SourceLocation AtLoc,
+ StmtArg Try, StmtArg Catch, StmtArg Finally) {
+ CurFunctionNeedsScopeChecking = true;
+ return Owned(new (Context) ObjCAtTryStmt(AtLoc, Try.takeAs<Stmt>(),
+ Catch.takeAs<Stmt>(),
+ Finally.takeAs<Stmt>()));
+}
+
+Action::OwningStmtResult
+Sema::ActOnObjCAtThrowStmt(SourceLocation AtLoc, ExprArg expr,Scope *CurScope) {
+ Expr *ThrowExpr = expr.takeAs<Expr>();
+ if (!ThrowExpr) {
+ // @throw without an expression designates a rethrow (which much occur
+ // in the context of an @catch clause).
+ Scope *AtCatchParent = CurScope;
+ while (AtCatchParent && !AtCatchParent->isAtCatchScope())
+ AtCatchParent = AtCatchParent->getParent();
+ if (!AtCatchParent)
+ return StmtError(Diag(AtLoc, diag::error_rethrow_used_outside_catch));
+ } else {
+ QualType ThrowType = ThrowExpr->getType();
+ // Make sure the expression type is an ObjC pointer or "void *".
+ if (!ThrowType->isObjCObjectPointerType()) {
+ const PointerType *PT = ThrowType->getAs<PointerType>();
+ if (!PT || !PT->getPointeeType()->isVoidType())
+ return StmtError(Diag(AtLoc, diag::error_objc_throw_expects_object)
+ << ThrowExpr->getType() << ThrowExpr->getSourceRange());
+ }
+ }
+ return Owned(new (Context) ObjCAtThrowStmt(AtLoc, ThrowExpr));
+}
+
+Action::OwningStmtResult
+Sema::ActOnObjCAtSynchronizedStmt(SourceLocation AtLoc, ExprArg SynchExpr,
+ StmtArg SynchBody) {
+ CurFunctionNeedsScopeChecking = true;
+
+ // Make sure the expression type is an ObjC pointer or "void *".
+ Expr *SyncExpr = static_cast<Expr*>(SynchExpr.get());
+ if (!SyncExpr->getType()->isObjCObjectPointerType()) {
+ const PointerType *PT = SyncExpr->getType()->getAs<PointerType>();
+ if (!PT || !PT->getPointeeType()->isVoidType())
+ return StmtError(Diag(AtLoc, diag::error_objc_synchronized_expects_object)
+ << SyncExpr->getType() << SyncExpr->getSourceRange());
+ }
+
+ return Owned(new (Context) ObjCAtSynchronizedStmt(AtLoc,
+ SynchExpr.takeAs<Stmt>(),
+ SynchBody.takeAs<Stmt>()));
+}
+
+/// ActOnCXXCatchBlock - Takes an exception declaration and a handler block
+/// and creates a proper catch handler from them.
+Action::OwningStmtResult
+Sema::ActOnCXXCatchBlock(SourceLocation CatchLoc, DeclPtrTy ExDecl,
+ StmtArg HandlerBlock) {
+ // There's nothing to test that ActOnExceptionDecl didn't already test.
+ return Owned(new (Context) CXXCatchStmt(CatchLoc,
+ cast_or_null<VarDecl>(ExDecl.getAs<Decl>()),
+ HandlerBlock.takeAs<Stmt>()));
+}
+
+class TypeWithHandler {
+ QualType t;
+ CXXCatchStmt *stmt;
+public:
+ TypeWithHandler(const QualType &type, CXXCatchStmt *statement)
+ : t(type), stmt(statement) {}
+
+ // An arbitrary order is fine as long as it places identical
+ // types next to each other.
+ bool operator<(const TypeWithHandler &y) const {
+ if (t.getAsOpaquePtr() < y.t.getAsOpaquePtr())
+ return true;
+ if (t.getAsOpaquePtr() > y.t.getAsOpaquePtr())
+ return false;
+ else
+ return getTypeSpecStartLoc() < y.getTypeSpecStartLoc();
+ }
+
+ bool operator==(const TypeWithHandler& other) const {
+ return t == other.t;
+ }
+
+ QualType getQualType() const { return t; }
+ CXXCatchStmt *getCatchStmt() const { return stmt; }
+ SourceLocation getTypeSpecStartLoc() const {
+ return stmt->getExceptionDecl()->getTypeSpecStartLoc();
+ }
+};
+
+/// ActOnCXXTryBlock - Takes a try compound-statement and a number of
+/// handlers and creates a try statement from them.
+Action::OwningStmtResult
+Sema::ActOnCXXTryBlock(SourceLocation TryLoc, StmtArg TryBlock,
+ MultiStmtArg RawHandlers) {
+ unsigned NumHandlers = RawHandlers.size();
+ assert(NumHandlers > 0 &&
+ "The parser shouldn't call this if there are no handlers.");
+ Stmt **Handlers = reinterpret_cast<Stmt**>(RawHandlers.get());
+
+ llvm::SmallVector<TypeWithHandler, 8> TypesWithHandlers;
+
+ for (unsigned i = 0; i < NumHandlers; ++i) {
+ CXXCatchStmt *Handler = llvm::cast<CXXCatchStmt>(Handlers[i]);
+ if (!Handler->getExceptionDecl()) {
+ if (i < NumHandlers - 1)
+ return StmtError(Diag(Handler->getLocStart(),
+ diag::err_early_catch_all));
+
+ continue;
+ }
+
+ const QualType CaughtType = Handler->getCaughtType();
+ const QualType CanonicalCaughtType = Context.getCanonicalType(CaughtType);
+ TypesWithHandlers.push_back(TypeWithHandler(CanonicalCaughtType, Handler));
+ }
+
+ // Detect handlers for the same type as an earlier one.
+ if (NumHandlers > 1) {
+ llvm::array_pod_sort(TypesWithHandlers.begin(), TypesWithHandlers.end());
+
+ TypeWithHandler prev = TypesWithHandlers[0];
+ for (unsigned i = 1; i < TypesWithHandlers.size(); ++i) {
+ TypeWithHandler curr = TypesWithHandlers[i];
+
+ if (curr == prev) {
+ Diag(curr.getTypeSpecStartLoc(),
+ diag::warn_exception_caught_by_earlier_handler)
+ << curr.getCatchStmt()->getCaughtType().getAsString();
+ Diag(prev.getTypeSpecStartLoc(),
+ diag::note_previous_exception_handler)
+ << prev.getCatchStmt()->getCaughtType().getAsString();
+ }
+
+ prev = curr;
+ }
+ }
+
+ // FIXME: We should detect handlers that cannot catch anything because an
+ // earlier handler catches a superclass. Need to find a method that is not
+ // quadratic for this.
+ // Neither of these are explicitly forbidden, but every compiler detects them
+ // and warns.
+
+ CurFunctionNeedsScopeChecking = true;
+ RawHandlers.release();
+ return Owned(CXXTryStmt::Create(Context, TryLoc,
+ static_cast<Stmt*>(TryBlock.release()),
+ Handlers, NumHandlers));
+}