summaryrefslogtreecommitdiff
path: root/clang/lib/Sema/SemaStmt.cpp
diff options
context:
space:
mode:
Diffstat (limited to 'clang/lib/Sema/SemaStmt.cpp')
-rw-r--r--clang/lib/Sema/SemaStmt.cpp2663
1 files changed, 2663 insertions, 0 deletions
diff --git a/clang/lib/Sema/SemaStmt.cpp b/clang/lib/Sema/SemaStmt.cpp
new file mode 100644
index 0000000..9052278
--- /dev/null
+++ b/clang/lib/Sema/SemaStmt.cpp
@@ -0,0 +1,2663 @@
+//===--- 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 (getLangOpts().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 (getLangOpts().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 (const PseudoObjectExpr *POE = dyn_cast<PseudoObjectExpr>(E)) {
+ const Expr *Source = POE->getSyntacticForm();
+ if (isa<ObjCSubscriptRefExpr>(Source))
+ DiagID = diag::warn_unused_container_subscript_expr;
+ else
+ 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);
+}
+
+void Sema::ActOnStartOfCompoundStmt() {
+ PushCompoundScope();
+}
+
+void Sema::ActOnFinishOfCompoundStmt() {
+ PopCompoundScope();
+}
+
+sema::CompoundScopeInfo &Sema::getCurCompoundScope() const {
+ return getCurFunction()->CompoundScopes.back();
+}
+
+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 (!getLangOpts().C99 && !getLangOpts().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]);
+ }
+
+ // Check for suspicious empty body (null statement) in `for' and `while'
+ // statements. Don't do anything for template instantiations, this just adds
+ // noise.
+ if (NumElts != 0 && !CurrentInstantiationScope &&
+ getCurCompoundScope().HasEmptyLoopBodies) {
+ for (unsigned i = 0; i != NumElts - 1; ++i)
+ DiagnoseEmptyLoopBody(Elts[i], Elts[i + 1]);
+ }
+
+ 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");
+
+ if (getCurFunction()->SwitchStack.empty()) {
+ Diag(CaseLoc, diag::err_case_not_in_switch);
+ return StmtError();
+ }
+
+ if (!getLangOpts().CPlusPlus0x) {
+ // C99 6.8.4.2p3: The expression shall be an integer constant.
+ // However, GCC allows any evaluatable integer expression.
+ if (!LHSVal->isTypeDependent() && !LHSVal->isValueDependent()) {
+ LHSVal = VerifyIntegerConstantExpression(LHSVal).take();
+ if (!LHSVal)
+ return StmtError();
+ }
+
+ // GCC extension: The expression shall be an integer constant.
+
+ if (RHSVal && !RHSVal->isTypeDependent() && !RHSVal->isValueDependent()) {
+ RHSVal = VerifyIntegerConstantExpression(RHSVal).take();
+ // Recover from an error by just forgetting about it.
+ }
+ }
+
+ 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::ActOnAttributedStmt(SourceLocation AttrLoc,
+ const AttrVec &Attrs,
+ Stmt *SubStmt) {
+ // Fill in the declaration and return it. Variable length will require to
+ // change this to AttributedStmt::Create(Context, ....);
+ // and probably using ArrayRef
+ AttributedStmt *LS = new (Context) AttributedStmt(AttrLoc, Attrs, SubStmt);
+ 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);
+
+ if (!elseStmt) {
+ DiagnoseEmptyStmtBody(ConditionExpr->getLocEnd(), thenStmt,
+ 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
+ = ConvertToIntegralOrEnumerationType(SwitchLoc, Cond,
+ 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),
+ /*AllowScopedEnumerations*/ true);
+ 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);
+
+ Expr *Lo = CS->getLHS();
+
+ if (Lo->isTypeDependent() || Lo->isValueDependent()) {
+ HasDependentValue = true;
+ break;
+ }
+
+ llvm::APSInt LoVal;
+
+ if (getLangOpts().CPlusPlus0x) {
+ // C++11 [stmt.switch]p2: the constant-expression shall be a converted
+ // constant expression of the promoted type of the switch condition.
+ ExprResult ConvLo =
+ CheckConvertedConstantExpression(Lo, CondType, LoVal, CCEK_CaseValue);
+ if (ConvLo.isInvalid()) {
+ CaseListIsErroneous = true;
+ continue;
+ }
+ Lo = ConvLo.take();
+ } else {
+ // We already verified that the expression has a i-c-e value (C99
+ // 6.8.4.2p3) - get that value now.
+ LoVal = Lo->EvaluateKnownConstInt(Context);
+
+ // If the LHS is not the same type as the condition, insert an implicit
+ // cast.
+ Lo = DefaultLvalueConversion(Lo).take();
+ Lo = ImpCastExprToType(Lo, CondType, CK_IntegralCast).take();
+ }
+
+ // Convert the value to the same width/sign as the condition had prior to
+ // integral promotions.
+ //
+ // FIXME: This causes us to reject valid code:
+ // switch ((char)c) { case 256: case 0: return 0; }
+ // Here we claim there is a duplicated condition value, but there is not.
+ ConvertIntegerToTypeWarnOnOverflow(LoVal, CondWidth, CondIsSigned,
+ Lo->getLocStart(),
+ diag::warn_case_value_overflow);
+
+ 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;
+
+ if (getLangOpts().CPlusPlus0x) {
+ // C++11 [stmt.switch]p2: the constant-expression shall be a converted
+ // constant expression of the promoted type of the switch condition.
+ ExprResult ConvHi =
+ CheckConvertedConstantExpression(Hi, CondType, HiVal,
+ CCEK_CaseValue);
+ if (ConvHi.isInvalid()) {
+ CaseListIsErroneous = true;
+ continue;
+ }
+ Hi = ConvHi.take();
+ } else {
+ HiVal = Hi->EvaluateKnownConstInt(Context);
+
+ // If the RHS is not the same type as the condition, insert an
+ // implicit cast.
+ Hi = DefaultLvalueConversion(Hi).take();
+ Hi = ImpCastExprToType(Hi, CondType, CK_IntegralCast).take();
+ }
+
+ // Convert the value to the same width/sign as the condition.
+ ConvertIntegerToTypeWarnOnOverflow(HiVal, CondWidth, CondIsSigned,
+ Hi->getLocStart(),
+ diag::warn_case_value_overflow);
+
+ 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.
+ 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)
+ << CondTypeBeforePromotion;
+ }
+ // 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)
+ << CondTypeBeforePromotion;
+ }
+
+ 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)
+ << CondTypeBeforePromotion;
+ }
+
+ // 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 (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;
+ UnhandledNames.push_back(EI->second->getDeclName());
+ }
+ }
+
+ if (TheDefaultStmt && UnhandledNames.empty())
+ Diag(TheDefaultStmt->getDefaultLoc(), diag::warn_unreachable_default);
+
+ // Produce a nice diagnostic if multiple values aren't handled.
+ switch (UnhandledNames.size()) {
+ case 0: break;
+ case 1:
+ Diag(CondExpr->getExprLoc(), TheDefaultStmt
+ ? diag::warn_def_missing_case1 : diag::warn_missing_case1)
+ << UnhandledNames[0];
+ break;
+ case 2:
+ Diag(CondExpr->getExprLoc(), TheDefaultStmt
+ ? diag::warn_def_missing_case2 : diag::warn_missing_case2)
+ << UnhandledNames[0] << UnhandledNames[1];
+ break;
+ case 3:
+ Diag(CondExpr->getExprLoc(), TheDefaultStmt
+ ? diag::warn_def_missing_case3 : diag::warn_missing_case3)
+ << UnhandledNames[0] << UnhandledNames[1] << UnhandledNames[2];
+ break;
+ default:
+ Diag(CondExpr->getExprLoc(), TheDefaultStmt
+ ? diag::warn_def_missing_cases : diag::warn_missing_cases)
+ << (unsigned)UnhandledNames.size()
+ << UnhandledNames[0] << UnhandledNames[1] << UnhandledNames[2];
+ break;
+ }
+
+ if (!hasCasesNotInSwitch)
+ SS->setAllEnumCasesCovered();
+ }
+ }
+
+ DiagnoseEmptyStmtBody(CondExpr->getLocEnd(), BodyStmt,
+ diag::warn_empty_switch_body);
+
+ // 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);
+
+ if (isa<NullStmt>(Body))
+ getCurCompoundScope().setHasEmptyLoopBodies();
+
+ 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 (!getLangOpts().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);
+
+ if (isa<NullStmt>(Body))
+ getCurCompoundScope().setHasEmptyLoopBodies();
+
+ 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) {
+ // Reduce placeholder expressions here. Note that this rejects the
+ // use of pseudo-object l-values in this position.
+ ExprResult result = CheckPlaceholderExpr(E);
+ if (result.isInvalid()) return StmtError();
+ E = result.take();
+
+ CheckImplicitConversions(E);
+
+ result = MaybeCreateExprWithCleanups(E);
+ if (result.isInvalid()) return StmtError();
+
+ return Owned(static_cast<Stmt*>(result.take()));
+}
+
+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),
+ getLangOpts().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 ((!isa<InitListExpr>(Init) && Init->getType()->isVoidType()) ||
+ SemaRef.DeduceAutoType(Decl->getTypeSourceInfo(), Init, InitTSI) ==
+ Sema::DAR_Failed)
+ 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.getLangOpts().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(),
+ /*TemplateKWLoc=*/SourceLocation(),
+ /*FirstQualifierInScope=*/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, /*AllowTypoCorrection=*/false);
+ 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();
+
+ CXXForRangeStmt *ForStmt = cast<CXXForRangeStmt>(S);
+ ForStmt->setBody(B);
+
+ DiagnoseEmptyStmtBody(ForStmt->getRParenLoc(), B,
+ diag::warn_empty_range_based_for_body);
+
+ 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();
+ E = MaybeCreateExprWithCleanups(E);
+ }
+
+ 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;
+}
+
+/// ActOnCapScopeReturnStmt - Utility routine to type-check return statements
+/// for capturing scopes.
+///
+StmtResult
+Sema::ActOnCapScopeReturnStmt(SourceLocation ReturnLoc, Expr *RetValExp) {
+ // If this is the first return we've seen, infer the return type.
+ // [expr.prim.lambda]p4 in C++11; block literals follow a superset of those
+ // rules which allows multiple return statements.
+ CapturingScopeInfo *CurCap = cast<CapturingScopeInfo>(getCurFunction());
+ if (CurCap->HasImplicitReturnType) {
+ QualType ReturnT;
+ if (RetValExp && !isa<InitListExpr>(RetValExp)) {
+ ExprResult Result = DefaultFunctionArrayLvalueConversion(RetValExp);
+ if (Result.isInvalid())
+ return StmtError();
+ RetValExp = Result.take();
+
+ if (!RetValExp->isTypeDependent())
+ ReturnT = RetValExp->getType();
+ else
+ ReturnT = Context.DependentTy;
+ } else {
+ if (RetValExp) {
+ // C++11 [expr.lambda.prim]p4 bans inferring the result from an
+ // initializer list, because it is not an expression (even
+ // though we represent it as one). We still deduce 'void'.
+ Diag(ReturnLoc, diag::err_lambda_return_init_list)
+ << RetValExp->getSourceRange();
+ }
+
+ ReturnT = Context.VoidTy;
+ }
+ // We require the return types to strictly match here.
+ if (!CurCap->ReturnType.isNull() &&
+ !CurCap->ReturnType->isDependentType() &&
+ !ReturnT->isDependentType() &&
+ !Context.hasSameType(ReturnT, CurCap->ReturnType)) {
+ Diag(ReturnLoc, diag::err_typecheck_missing_return_type_incompatible)
+ << ReturnT << CurCap->ReturnType
+ << (getCurLambda() != 0);
+ return StmtError();
+ }
+ CurCap->ReturnType = ReturnT;
+ }
+ QualType FnRetType = CurCap->ReturnType;
+ assert(!FnRetType.isNull());
+
+ if (BlockScopeInfo *CurBlock = dyn_cast<BlockScopeInfo>(CurCap)) {
+ if (CurBlock->FunctionType->getAs<FunctionType>()->getNoReturnAttr()) {
+ Diag(ReturnLoc, diag::err_noreturn_block_has_return_expr);
+ return StmtError();
+ }
+ } else {
+ LambdaScopeInfo *LSI = cast<LambdaScopeInfo>(CurCap);
+ if (LSI->CallOperator->getType()->getAs<FunctionType>()->getNoReturnAttr()){
+ Diag(ReturnLoc, diag::err_noreturn_lambda_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 && !isa<InitListExpr>(RetValExp) &&
+ !(getLangOpts().CPlusPlus &&
+ (RetValExp->isTypeDependent() ||
+ RetValExp->getType()->isVoidType()))) {
+ if (!getLangOpts().CPlusPlus &&
+ RetValExp->getType()->isVoidType())
+ Diag(ReturnLoc, diag::ext_return_has_void_expr) << "literal" << 2;
+ else {
+ 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 (getLangOpts().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 (isa<CapturingScopeInfo>(getCurFunction()))
+ return ActOnCapScopeReturnStmt(ReturnLoc, RetValExp);
+
+ QualType FnRetType;
+ QualType RelatedRetType;
+ 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)
+ << FD->getDeclName();
+ } else if (ObjCMethodDecl *MD = getCurMethodDecl()) {
+ FnRetType = 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.
+ RelatedRetType = Context.getObjCInterfaceType(MD->getClassInterface());
+ RelatedRetType = Context.getObjCObjectPointerType(RelatedRetType);
+ }
+ } else // If we don't have a function/method context, bail.
+ return StmtError();
+
+ ReturnStmt *Result = 0;
+ if (FnRetType->isVoidType()) {
+ if (RetValExp) {
+ if (isa<InitListExpr>(RetValExp)) {
+ // We simply never allow init lists as the return value of void
+ // functions. This is compatible because this was never allowed before,
+ // so there's no legacy code to deal with.
+ 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, diag::err_return_init_list)
+ << CurDecl->getDeclName() << FunctionKind
+ << RetValExp->getSourceRange();
+
+ // Drop the expression.
+ RetValExp = 0;
+ } else 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 ||
+ !getLangOpts().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();
+ }
+ }
+
+ if (RetValExp) {
+ 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 (getLangOpts().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
+
+ if (!RelatedRetType.isNull()) {
+ // If we have a related result type, perform an extra conversion here.
+ // FIXME: The diagnostics here don't really describe what is happening.
+ InitializedEntity Entity =
+ InitializedEntity::InitializeTemporary(RelatedRetType);
+
+ ExprResult Res = PerformCopyInitialization(Entity, SourceLocation(),
+ RetValExp);
+ if (Res.isInvalid()) {
+ // FIXME: Cleanup temporaries here, anyway?
+ return StmtError();
+ }
+ RetValExp = Res.takeAs<Expr>();
+ }
+
+ // 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) {
+ 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 (getLangOpts().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.getLangOpts().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 (!getLangOpts().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 (!getLangOpts().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 (!getLangOpts().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);
+}