1 //===--- SemaStmt.cpp - Semantic Analysis for Statements ------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file implements semantic analysis for statements.
12 //===----------------------------------------------------------------------===//
14 #include "clang/Sema/SemaInternal.h"
15 #include "clang/Sema/Scope.h"
16 #include "clang/Sema/ScopeInfo.h"
17 #include "clang/Sema/Initialization.h"
18 #include "clang/Sema/Lookup.h"
19 #include "clang/AST/APValue.h"
20 #include "clang/AST/ASTContext.h"
21 #include "clang/AST/DeclObjC.h"
22 #include "clang/AST/ExprCXX.h"
23 #include "clang/AST/ExprObjC.h"
24 #include "clang/AST/StmtObjC.h"
25 #include "clang/AST/StmtCXX.h"
26 #include "clang/AST/TypeLoc.h"
27 #include "clang/Lex/Preprocessor.h"
28 #include "clang/Basic/TargetInfo.h"
29 #include "llvm/ADT/ArrayRef.h"
30 #include "llvm/ADT/STLExtras.h"
31 #include "llvm/ADT/SmallVector.h"
32 using namespace clang;
35 StmtResult Sema::ActOnExprStmt(FullExprArg expr) {
37 if (!E) // FIXME: FullExprArg has no error state?
40 // C99 6.8.3p2: The expression in an expression statement is evaluated as a
41 // void expression for its side effects. Conversion to void allows any
42 // operand, even incomplete types.
44 // Same thing in for stmt first clause (when expr) and third clause.
45 return Owned(static_cast<Stmt*>(E));
49 StmtResult Sema::ActOnNullStmt(SourceLocation SemiLoc,
50 SourceLocation LeadingEmptyMacroLoc) {
51 return Owned(new (Context) NullStmt(SemiLoc, LeadingEmptyMacroLoc));
54 StmtResult Sema::ActOnDeclStmt(DeclGroupPtrTy dg, SourceLocation StartLoc,
55 SourceLocation EndLoc) {
56 DeclGroupRef DG = dg.getAsVal<DeclGroupRef>();
58 // If we have an invalid decl, just return an error.
59 if (DG.isNull()) return StmtError();
61 return Owned(new (Context) DeclStmt(DG, StartLoc, EndLoc));
64 void Sema::ActOnForEachDeclStmt(DeclGroupPtrTy dg) {
65 DeclGroupRef DG = dg.getAsVal<DeclGroupRef>();
67 // If we have an invalid decl, just return.
68 if (DG.isNull() || !DG.isSingleDecl()) return;
69 // suppress any potential 'unused variable' warning.
70 DG.getSingleDecl()->setUsed();
73 void Sema::DiagnoseUnusedExprResult(const Stmt *S) {
74 if (const LabelStmt *Label = dyn_cast_or_null<LabelStmt>(S))
75 return DiagnoseUnusedExprResult(Label->getSubStmt());
77 const Expr *E = dyn_cast_or_null<Expr>(S);
83 if (!E->isUnusedResultAWarning(Loc, R1, R2, Context))
86 // Okay, we have an unused result. Depending on what the base expression is,
87 // we might want to make a more specific diagnostic. Check for one of these
89 unsigned DiagID = diag::warn_unused_expr;
90 if (const ExprWithCleanups *Temps = dyn_cast<ExprWithCleanups>(E))
91 E = Temps->getSubExpr();
92 if (const CXXBindTemporaryExpr *TempExpr = dyn_cast<CXXBindTemporaryExpr>(E))
93 E = TempExpr->getSubExpr();
95 E = E->IgnoreParenImpCasts();
96 if (const CallExpr *CE = dyn_cast<CallExpr>(E)) {
97 if (E->getType()->isVoidType())
100 // If the callee has attribute pure, const, or warn_unused_result, warn with
101 // a more specific message to make it clear what is happening.
102 if (const Decl *FD = CE->getCalleeDecl()) {
103 if (FD->getAttr<WarnUnusedResultAttr>()) {
104 Diag(Loc, diag::warn_unused_call) << R1 << R2 << "warn_unused_result";
107 if (FD->getAttr<PureAttr>()) {
108 Diag(Loc, diag::warn_unused_call) << R1 << R2 << "pure";
111 if (FD->getAttr<ConstAttr>()) {
112 Diag(Loc, diag::warn_unused_call) << R1 << R2 << "const";
116 } else if (const ObjCMessageExpr *ME = dyn_cast<ObjCMessageExpr>(E)) {
117 const ObjCMethodDecl *MD = ME->getMethodDecl();
118 if (MD && MD->getAttr<WarnUnusedResultAttr>()) {
119 Diag(Loc, diag::warn_unused_call) << R1 << R2 << "warn_unused_result";
122 } else if (isa<ObjCPropertyRefExpr>(E)) {
123 DiagID = diag::warn_unused_property_expr;
124 } else if (const CXXFunctionalCastExpr *FC
125 = dyn_cast<CXXFunctionalCastExpr>(E)) {
126 if (isa<CXXConstructExpr>(FC->getSubExpr()) ||
127 isa<CXXTemporaryObjectExpr>(FC->getSubExpr()))
130 // Diagnose "(void*) blah" as a typo for "(void) blah".
131 else if (const CStyleCastExpr *CE = dyn_cast<CStyleCastExpr>(E)) {
132 TypeSourceInfo *TI = CE->getTypeInfoAsWritten();
133 QualType T = TI->getType();
135 // We really do want to use the non-canonical type here.
136 if (T == Context.VoidPtrTy) {
137 PointerTypeLoc TL = cast<PointerTypeLoc>(TI->getTypeLoc());
139 Diag(Loc, diag::warn_unused_voidptr)
140 << FixItHint::CreateRemoval(TL.getStarLoc());
145 DiagRuntimeBehavior(Loc, 0, PDiag(DiagID) << R1 << R2);
149 Sema::ActOnCompoundStmt(SourceLocation L, SourceLocation R,
150 MultiStmtArg elts, bool isStmtExpr) {
151 unsigned NumElts = elts.size();
152 Stmt **Elts = reinterpret_cast<Stmt**>(elts.release());
153 // If we're in C89 mode, check that we don't have any decls after stmts. If
154 // so, emit an extension diagnostic.
155 if (!getLangOptions().C99 && !getLangOptions().CPlusPlus) {
156 // Note that __extension__ can be around a decl.
158 // Skip over all declarations.
159 for (; i != NumElts && isa<DeclStmt>(Elts[i]); ++i)
162 // We found the end of the list or a statement. Scan for another declstmt.
163 for (; i != NumElts && !isa<DeclStmt>(Elts[i]); ++i)
167 Decl *D = *cast<DeclStmt>(Elts[i])->decl_begin();
168 Diag(D->getLocation(), diag::ext_mixed_decls_code);
171 // Warn about unused expressions in statements.
172 for (unsigned i = 0; i != NumElts; ++i) {
173 // Ignore statements that are last in a statement expression.
174 if (isStmtExpr && i == NumElts - 1)
177 DiagnoseUnusedExprResult(Elts[i]);
180 return Owned(new (Context) CompoundStmt(Context, Elts, NumElts, L, R));
184 Sema::ActOnCaseStmt(SourceLocation CaseLoc, Expr *LHSVal,
185 SourceLocation DotDotDotLoc, Expr *RHSVal,
186 SourceLocation ColonLoc) {
187 assert((LHSVal != 0) && "missing expression in case statement");
189 // C99 6.8.4.2p3: The expression shall be an integer constant.
190 // However, GCC allows any evaluatable integer expression.
191 if (!LHSVal->isTypeDependent() && !LHSVal->isValueDependent() &&
192 VerifyIntegerConstantExpression(LHSVal))
195 // GCC extension: The expression shall be an integer constant.
197 if (RHSVal && !RHSVal->isTypeDependent() && !RHSVal->isValueDependent() &&
198 VerifyIntegerConstantExpression(RHSVal)) {
199 RHSVal = 0; // Recover by just forgetting about it.
202 if (getCurFunction()->SwitchStack.empty()) {
203 Diag(CaseLoc, diag::err_case_not_in_switch);
207 CaseStmt *CS = new (Context) CaseStmt(LHSVal, RHSVal, CaseLoc, DotDotDotLoc,
209 getCurFunction()->SwitchStack.back()->addSwitchCase(CS);
213 /// ActOnCaseStmtBody - This installs a statement as the body of a case.
214 void Sema::ActOnCaseStmtBody(Stmt *caseStmt, Stmt *SubStmt) {
215 CaseStmt *CS = static_cast<CaseStmt*>(caseStmt);
216 CS->setSubStmt(SubStmt);
220 Sema::ActOnDefaultStmt(SourceLocation DefaultLoc, SourceLocation ColonLoc,
221 Stmt *SubStmt, Scope *CurScope) {
222 if (getCurFunction()->SwitchStack.empty()) {
223 Diag(DefaultLoc, diag::err_default_not_in_switch);
224 return Owned(SubStmt);
227 DefaultStmt *DS = new (Context) DefaultStmt(DefaultLoc, ColonLoc, SubStmt);
228 getCurFunction()->SwitchStack.back()->addSwitchCase(DS);
233 Sema::ActOnLabelStmt(SourceLocation IdentLoc, LabelDecl *TheDecl,
234 SourceLocation ColonLoc, Stmt *SubStmt) {
236 // If the label was multiply defined, reject it now.
237 if (TheDecl->getStmt()) {
238 Diag(IdentLoc, diag::err_redefinition_of_label) << TheDecl->getDeclName();
239 Diag(TheDecl->getLocation(), diag::note_previous_definition);
240 return Owned(SubStmt);
243 // Otherwise, things are good. Fill in the declaration and return it.
244 LabelStmt *LS = new (Context) LabelStmt(IdentLoc, TheDecl, SubStmt);
245 TheDecl->setStmt(LS);
246 if (!TheDecl->isGnuLocal())
247 TheDecl->setLocation(IdentLoc);
252 Sema::ActOnIfStmt(SourceLocation IfLoc, FullExprArg CondVal, Decl *CondVar,
253 Stmt *thenStmt, SourceLocation ElseLoc,
255 ExprResult CondResult(CondVal.release());
257 VarDecl *ConditionVar = 0;
259 ConditionVar = cast<VarDecl>(CondVar);
260 CondResult = CheckConditionVariable(ConditionVar, IfLoc, true);
261 if (CondResult.isInvalid())
264 Expr *ConditionExpr = CondResult.takeAs<Expr>();
268 DiagnoseUnusedExprResult(thenStmt);
270 // Warn if the if block has a null body without an else value.
271 // this helps prevent bugs due to typos, such as
276 if (NullStmt* stmt = dyn_cast<NullStmt>(thenStmt))
277 // But do not warn if the body is a macro that expands to nothing, e.g:
283 if (!stmt->hasLeadingEmptyMacro())
284 Diag(stmt->getSemiLoc(), diag::warn_empty_if_body);
287 DiagnoseUnusedExprResult(elseStmt);
289 return Owned(new (Context) IfStmt(Context, IfLoc, ConditionVar, ConditionExpr,
290 thenStmt, ElseLoc, elseStmt));
293 /// ConvertIntegerToTypeWarnOnOverflow - Convert the specified APInt to have
294 /// the specified width and sign. If an overflow occurs, detect it and emit
295 /// the specified diagnostic.
296 void Sema::ConvertIntegerToTypeWarnOnOverflow(llvm::APSInt &Val,
297 unsigned NewWidth, bool NewSign,
300 // Perform a conversion to the promoted condition type if needed.
301 if (NewWidth > Val.getBitWidth()) {
302 // If this is an extension, just do it.
303 Val = Val.extend(NewWidth);
304 Val.setIsSigned(NewSign);
306 // If the input was signed and negative and the output is
307 // unsigned, don't bother to warn: this is implementation-defined
309 // FIXME: Introduce a second, default-ignored warning for this case?
310 } else if (NewWidth < Val.getBitWidth()) {
311 // If this is a truncation, check for overflow.
312 llvm::APSInt ConvVal(Val);
313 ConvVal = ConvVal.trunc(NewWidth);
314 ConvVal.setIsSigned(NewSign);
315 ConvVal = ConvVal.extend(Val.getBitWidth());
316 ConvVal.setIsSigned(Val.isSigned());
318 Diag(Loc, DiagID) << Val.toString(10) << ConvVal.toString(10);
320 // Regardless of whether a diagnostic was emitted, really do the
322 Val = Val.trunc(NewWidth);
323 Val.setIsSigned(NewSign);
324 } else if (NewSign != Val.isSigned()) {
325 // Convert the sign to match the sign of the condition. This can cause
326 // overflow as well: unsigned(INTMIN)
327 // We don't diagnose this overflow, because it is implementation-defined
329 // FIXME: Introduce a second, default-ignored warning for this case?
330 llvm::APSInt OldVal(Val);
331 Val.setIsSigned(NewSign);
336 struct CaseCompareFunctor {
337 bool operator()(const std::pair<llvm::APSInt, CaseStmt*> &LHS,
338 const llvm::APSInt &RHS) {
339 return LHS.first < RHS;
341 bool operator()(const std::pair<llvm::APSInt, CaseStmt*> &LHS,
342 const std::pair<llvm::APSInt, CaseStmt*> &RHS) {
343 return LHS.first < RHS.first;
345 bool operator()(const llvm::APSInt &LHS,
346 const std::pair<llvm::APSInt, CaseStmt*> &RHS) {
347 return LHS < RHS.first;
352 /// CmpCaseVals - Comparison predicate for sorting case values.
354 static bool CmpCaseVals(const std::pair<llvm::APSInt, CaseStmt*>& lhs,
355 const std::pair<llvm::APSInt, CaseStmt*>& rhs) {
356 if (lhs.first < rhs.first)
359 if (lhs.first == rhs.first &&
360 lhs.second->getCaseLoc().getRawEncoding()
361 < rhs.second->getCaseLoc().getRawEncoding())
366 /// CmpEnumVals - Comparison predicate for sorting enumeration values.
368 static bool CmpEnumVals(const std::pair<llvm::APSInt, EnumConstantDecl*>& lhs,
369 const std::pair<llvm::APSInt, EnumConstantDecl*>& rhs)
371 return lhs.first < rhs.first;
374 /// EqEnumVals - Comparison preficate for uniqing enumeration values.
376 static bool EqEnumVals(const std::pair<llvm::APSInt, EnumConstantDecl*>& lhs,
377 const std::pair<llvm::APSInt, EnumConstantDecl*>& rhs)
379 return lhs.first == rhs.first;
382 /// GetTypeBeforeIntegralPromotion - Returns the pre-promotion type of
383 /// potentially integral-promoted expression @p expr.
384 static QualType GetTypeBeforeIntegralPromotion(const Expr* expr) {
385 if (const CastExpr *ImplicitCast = dyn_cast<ImplicitCastExpr>(expr)) {
386 const Expr *ExprBeforePromotion = ImplicitCast->getSubExpr();
387 QualType TypeBeforePromotion = ExprBeforePromotion->getType();
388 if (TypeBeforePromotion->isIntegralOrEnumerationType()) {
389 return TypeBeforePromotion;
392 return expr->getType();
396 Sema::ActOnStartOfSwitchStmt(SourceLocation SwitchLoc, Expr *Cond,
398 ExprResult CondResult;
400 VarDecl *ConditionVar = 0;
402 ConditionVar = cast<VarDecl>(CondVar);
403 CondResult = CheckConditionVariable(ConditionVar, SourceLocation(), false);
404 if (CondResult.isInvalid())
407 Cond = CondResult.release();
414 = ConvertToIntegralOrEnumerationType(SwitchLoc, Cond,
415 PDiag(diag::err_typecheck_statement_requires_integer),
416 PDiag(diag::err_switch_incomplete_class_type)
417 << Cond->getSourceRange(),
418 PDiag(diag::err_switch_explicit_conversion),
419 PDiag(diag::note_switch_conversion),
420 PDiag(diag::err_switch_multiple_conversions),
421 PDiag(diag::note_switch_conversion),
423 if (CondResult.isInvalid()) return StmtError();
424 Cond = CondResult.take();
427 CheckImplicitConversions(Cond, SwitchLoc);
428 CondResult = MaybeCreateExprWithCleanups(Cond);
429 if (CondResult.isInvalid())
431 Cond = CondResult.take();
434 getCurFunction()->setHasBranchIntoScope();
436 SwitchStmt *SS = new (Context) SwitchStmt(Context, ConditionVar, Cond);
437 getCurFunction()->SwitchStack.push_back(SS);
441 static void AdjustAPSInt(llvm::APSInt &Val, unsigned BitWidth, bool IsSigned) {
442 if (Val.getBitWidth() < BitWidth)
443 Val = Val.extend(BitWidth);
444 else if (Val.getBitWidth() > BitWidth)
445 Val = Val.trunc(BitWidth);
446 Val.setIsSigned(IsSigned);
450 Sema::ActOnFinishSwitchStmt(SourceLocation SwitchLoc, Stmt *Switch,
452 SwitchStmt *SS = cast<SwitchStmt>(Switch);
453 assert(SS == getCurFunction()->SwitchStack.back() &&
454 "switch stack missing push/pop!");
456 SS->setBody(BodyStmt, SwitchLoc);
457 getCurFunction()->SwitchStack.pop_back();
459 if (SS->getCond() == 0)
462 Expr *CondExpr = SS->getCond();
463 Expr *CondExprBeforePromotion = CondExpr;
464 QualType CondTypeBeforePromotion =
465 GetTypeBeforeIntegralPromotion(CondExpr);
467 // C99 6.8.4.2p5 - Integer promotions are performed on the controlling expr.
468 ExprResult CondResult = UsualUnaryConversions(CondExpr);
469 if (CondResult.isInvalid())
471 CondExpr = CondResult.take();
472 QualType CondType = CondExpr->getType();
473 SS->setCond(CondExpr);
476 // Integral promotions are performed (on the switch condition).
478 // A case value unrepresentable by the original switch condition
479 // type (before the promotion) doesn't make sense, even when it can
480 // be represented by the promoted type. Therefore we need to find
481 // the pre-promotion type of the switch condition.
482 if (!CondExpr->isTypeDependent()) {
483 // We have already converted the expression to an integral or enumeration
484 // type, when we started the switch statement. If we don't have an
485 // appropriate type now, just return an error.
486 if (!CondType->isIntegralOrEnumerationType())
489 if (CondExpr->isKnownToHaveBooleanValue()) {
490 // switch(bool_expr) {...} is often a programmer error, e.g.
491 // switch(n && mask) { ... } // Doh - should be "n & mask".
492 // One can always use an if statement instead of switch(bool_expr).
493 Diag(SwitchLoc, diag::warn_bool_switch_condition)
494 << CondExpr->getSourceRange();
498 // Get the bitwidth of the switched-on value before promotions. We must
499 // convert the integer case values to this width before comparison.
500 bool HasDependentValue
501 = CondExpr->isTypeDependent() || CondExpr->isValueDependent();
503 = HasDependentValue ? 0 : Context.getIntWidth(CondTypeBeforePromotion);
505 = CondTypeBeforePromotion->isSignedIntegerOrEnumerationType();
507 // Accumulate all of the case values in a vector so that we can sort them
508 // and detect duplicates. This vector contains the APInt for the case after
509 // it has been converted to the condition type.
510 typedef llvm::SmallVector<std::pair<llvm::APSInt, CaseStmt*>, 64> CaseValsTy;
513 // Keep track of any GNU case ranges we see. The APSInt is the low value.
514 typedef std::vector<std::pair<llvm::APSInt, CaseStmt*> > CaseRangesTy;
515 CaseRangesTy CaseRanges;
517 DefaultStmt *TheDefaultStmt = 0;
519 bool CaseListIsErroneous = false;
521 for (SwitchCase *SC = SS->getSwitchCaseList(); SC && !HasDependentValue;
522 SC = SC->getNextSwitchCase()) {
524 if (DefaultStmt *DS = dyn_cast<DefaultStmt>(SC)) {
525 if (TheDefaultStmt) {
526 Diag(DS->getDefaultLoc(), diag::err_multiple_default_labels_defined);
527 Diag(TheDefaultStmt->getDefaultLoc(), diag::note_duplicate_case_prev);
529 // FIXME: Remove the default statement from the switch block so that
530 // we'll return a valid AST. This requires recursing down the AST and
531 // finding it, not something we are set up to do right now. For now,
532 // just lop the entire switch stmt out of the AST.
533 CaseListIsErroneous = true;
538 CaseStmt *CS = cast<CaseStmt>(SC);
540 // We already verified that the expression has a i-c-e value (C99
541 // 6.8.4.2p3) - get that value now.
542 Expr *Lo = CS->getLHS();
544 if (Lo->isTypeDependent() || Lo->isValueDependent()) {
545 HasDependentValue = true;
549 llvm::APSInt LoVal = Lo->EvaluateAsInt(Context);
551 // Convert the value to the same width/sign as the condition.
552 ConvertIntegerToTypeWarnOnOverflow(LoVal, CondWidth, CondIsSigned,
554 diag::warn_case_value_overflow);
556 // If the LHS is not the same type as the condition, insert an implicit
558 Lo = ImpCastExprToType(Lo, CondType, CK_IntegralCast).take();
561 // If this is a case range, remember it in CaseRanges, otherwise CaseVals.
563 if (CS->getRHS()->isTypeDependent() ||
564 CS->getRHS()->isValueDependent()) {
565 HasDependentValue = true;
568 CaseRanges.push_back(std::make_pair(LoVal, CS));
570 CaseVals.push_back(std::make_pair(LoVal, CS));
574 if (!HasDependentValue) {
575 // If we don't have a default statement, check whether the
576 // condition is constant.
577 llvm::APSInt ConstantCondValue;
578 bool HasConstantCond = false;
579 bool ShouldCheckConstantCond = false;
580 if (!HasDependentValue && !TheDefaultStmt) {
581 Expr::EvalResult Result;
582 HasConstantCond = CondExprBeforePromotion->Evaluate(Result, Context);
583 if (HasConstantCond) {
584 assert(Result.Val.isInt() && "switch condition evaluated to non-int");
585 ConstantCondValue = Result.Val.getInt();
586 ShouldCheckConstantCond = true;
588 assert(ConstantCondValue.getBitWidth() == CondWidth &&
589 ConstantCondValue.isSigned() == CondIsSigned);
593 // Sort all the scalar case values so we can easily detect duplicates.
594 std::stable_sort(CaseVals.begin(), CaseVals.end(), CmpCaseVals);
596 if (!CaseVals.empty()) {
597 for (unsigned i = 0, e = CaseVals.size(); i != e; ++i) {
598 if (ShouldCheckConstantCond &&
599 CaseVals[i].first == ConstantCondValue)
600 ShouldCheckConstantCond = false;
602 if (i != 0 && CaseVals[i].first == CaseVals[i-1].first) {
603 // If we have a duplicate, report it.
604 Diag(CaseVals[i].second->getLHS()->getLocStart(),
605 diag::err_duplicate_case) << CaseVals[i].first.toString(10);
606 Diag(CaseVals[i-1].second->getLHS()->getLocStart(),
607 diag::note_duplicate_case_prev);
608 // FIXME: We really want to remove the bogus case stmt from the
609 // substmt, but we have no way to do this right now.
610 CaseListIsErroneous = true;
615 // Detect duplicate case ranges, which usually don't exist at all in
617 if (!CaseRanges.empty()) {
618 // Sort all the case ranges by their low value so we can easily detect
619 // overlaps between ranges.
620 std::stable_sort(CaseRanges.begin(), CaseRanges.end());
622 // Scan the ranges, computing the high values and removing empty ranges.
623 std::vector<llvm::APSInt> HiVals;
624 for (unsigned i = 0, e = CaseRanges.size(); i != e; ++i) {
625 llvm::APSInt &LoVal = CaseRanges[i].first;
626 CaseStmt *CR = CaseRanges[i].second;
627 Expr *Hi = CR->getRHS();
628 llvm::APSInt HiVal = Hi->EvaluateAsInt(Context);
630 // Convert the value to the same width/sign as the condition.
631 ConvertIntegerToTypeWarnOnOverflow(HiVal, CondWidth, CondIsSigned,
633 diag::warn_case_value_overflow);
635 // If the LHS is not the same type as the condition, insert an implicit
637 Hi = ImpCastExprToType(Hi, CondType, CK_IntegralCast).take();
640 // If the low value is bigger than the high value, the case is empty.
642 Diag(CR->getLHS()->getLocStart(), diag::warn_case_empty_range)
643 << SourceRange(CR->getLHS()->getLocStart(),
645 CaseRanges.erase(CaseRanges.begin()+i);
650 if (ShouldCheckConstantCond &&
651 LoVal <= ConstantCondValue &&
652 ConstantCondValue <= HiVal)
653 ShouldCheckConstantCond = false;
655 HiVals.push_back(HiVal);
658 // Rescan the ranges, looking for overlap with singleton values and other
659 // ranges. Since the range list is sorted, we only need to compare case
660 // ranges with their neighbors.
661 for (unsigned i = 0, e = CaseRanges.size(); i != e; ++i) {
662 llvm::APSInt &CRLo = CaseRanges[i].first;
663 llvm::APSInt &CRHi = HiVals[i];
664 CaseStmt *CR = CaseRanges[i].second;
666 // Check to see whether the case range overlaps with any
668 CaseStmt *OverlapStmt = 0;
669 llvm::APSInt OverlapVal(32);
671 // Find the smallest value >= the lower bound. If I is in the
672 // case range, then we have overlap.
673 CaseValsTy::iterator I = std::lower_bound(CaseVals.begin(),
674 CaseVals.end(), CRLo,
675 CaseCompareFunctor());
676 if (I != CaseVals.end() && I->first < CRHi) {
677 OverlapVal = I->first; // Found overlap with scalar.
678 OverlapStmt = I->second;
681 // Find the smallest value bigger than the upper bound.
682 I = std::upper_bound(I, CaseVals.end(), CRHi, CaseCompareFunctor());
683 if (I != CaseVals.begin() && (I-1)->first >= CRLo) {
684 OverlapVal = (I-1)->first; // Found overlap with scalar.
685 OverlapStmt = (I-1)->second;
688 // Check to see if this case stmt overlaps with the subsequent
690 if (i && CRLo <= HiVals[i-1]) {
691 OverlapVal = HiVals[i-1]; // Found overlap with range.
692 OverlapStmt = CaseRanges[i-1].second;
696 // If we have a duplicate, report it.
697 Diag(CR->getLHS()->getLocStart(), diag::err_duplicate_case)
698 << OverlapVal.toString(10);
699 Diag(OverlapStmt->getLHS()->getLocStart(),
700 diag::note_duplicate_case_prev);
701 // FIXME: We really want to remove the bogus case stmt from the
702 // substmt, but we have no way to do this right now.
703 CaseListIsErroneous = true;
708 // Complain if we have a constant condition and we didn't find a match.
709 if (!CaseListIsErroneous && ShouldCheckConstantCond) {
710 // TODO: it would be nice if we printed enums as enums, chars as
712 Diag(CondExpr->getExprLoc(), diag::warn_missing_case_for_condition)
713 << ConstantCondValue.toString(10)
714 << CondExpr->getSourceRange();
717 // Check to see if switch is over an Enum and handles all of its
718 // values. We only issue a warning if there is not 'default:', but
719 // we still do the analysis to preserve this information in the AST
720 // (which can be used by flow-based analyes).
722 const EnumType *ET = CondTypeBeforePromotion->getAs<EnumType>();
724 // If switch has default case, then ignore it.
725 if (!CaseListIsErroneous && !HasConstantCond && ET) {
726 const EnumDecl *ED = ET->getDecl();
727 typedef llvm::SmallVector<std::pair<llvm::APSInt, EnumConstantDecl*>, 64>
731 // Gather all enum values, set their type and sort them,
732 // allowing easier comparison with CaseVals.
733 for (EnumDecl::enumerator_iterator EDI = ED->enumerator_begin();
734 EDI != ED->enumerator_end(); ++EDI) {
735 llvm::APSInt Val = EDI->getInitVal();
736 AdjustAPSInt(Val, CondWidth, CondIsSigned);
737 EnumVals.push_back(std::make_pair(Val, *EDI));
739 std::stable_sort(EnumVals.begin(), EnumVals.end(), CmpEnumVals);
740 EnumValsTy::iterator EIend =
741 std::unique(EnumVals.begin(), EnumVals.end(), EqEnumVals);
743 // See which case values aren't in enum.
744 // TODO: we might want to check whether case values are out of the
745 // enum even if we don't want to check whether all cases are handled.
746 if (!TheDefaultStmt) {
747 EnumValsTy::const_iterator EI = EnumVals.begin();
748 for (CaseValsTy::const_iterator CI = CaseVals.begin();
749 CI != CaseVals.end(); CI++) {
750 while (EI != EIend && EI->first < CI->first)
752 if (EI == EIend || EI->first > CI->first)
753 Diag(CI->second->getLHS()->getExprLoc(), diag::warn_not_in_enum)
754 << ED->getDeclName();
756 // See which of case ranges aren't in enum
757 EI = EnumVals.begin();
758 for (CaseRangesTy::const_iterator RI = CaseRanges.begin();
759 RI != CaseRanges.end() && EI != EIend; RI++) {
760 while (EI != EIend && EI->first < RI->first)
763 if (EI == EIend || EI->first != RI->first) {
764 Diag(RI->second->getLHS()->getExprLoc(), diag::warn_not_in_enum)
765 << ED->getDeclName();
768 llvm::APSInt Hi = RI->second->getRHS()->EvaluateAsInt(Context);
769 AdjustAPSInt(Hi, CondWidth, CondIsSigned);
770 while (EI != EIend && EI->first < Hi)
772 if (EI == EIend || EI->first != Hi)
773 Diag(RI->second->getRHS()->getExprLoc(), diag::warn_not_in_enum)
774 << ED->getDeclName();
778 // Check which enum vals aren't in switch
779 CaseValsTy::const_iterator CI = CaseVals.begin();
780 CaseRangesTy::const_iterator RI = CaseRanges.begin();
781 bool hasCasesNotInSwitch = false;
783 llvm::SmallVector<DeclarationName,8> UnhandledNames;
785 for (EnumValsTy::const_iterator EI = EnumVals.begin(); EI != EIend; EI++){
786 // Drop unneeded case values
788 while (CI != CaseVals.end() && CI->first < EI->first)
791 if (CI != CaseVals.end() && CI->first == EI->first)
794 // Drop unneeded case ranges
795 for (; RI != CaseRanges.end(); RI++) {
796 llvm::APSInt Hi = RI->second->getRHS()->EvaluateAsInt(Context);
797 AdjustAPSInt(Hi, CondWidth, CondIsSigned);
802 if (RI == CaseRanges.end() || EI->first < RI->first) {
803 hasCasesNotInSwitch = true;
805 UnhandledNames.push_back(EI->second->getDeclName());
809 // Produce a nice diagnostic if multiple values aren't handled.
810 switch (UnhandledNames.size()) {
813 Diag(CondExpr->getExprLoc(), diag::warn_missing_case1)
814 << UnhandledNames[0];
817 Diag(CondExpr->getExprLoc(), diag::warn_missing_case2)
818 << UnhandledNames[0] << UnhandledNames[1];
821 Diag(CondExpr->getExprLoc(), diag::warn_missing_case3)
822 << UnhandledNames[0] << UnhandledNames[1] << UnhandledNames[2];
825 Diag(CondExpr->getExprLoc(), diag::warn_missing_cases)
826 << (unsigned)UnhandledNames.size()
827 << UnhandledNames[0] << UnhandledNames[1] << UnhandledNames[2];
831 if (!hasCasesNotInSwitch)
832 SS->setAllEnumCasesCovered();
836 // FIXME: If the case list was broken is some way, we don't have a good system
837 // to patch it up. Instead, just return the whole substmt as broken.
838 if (CaseListIsErroneous)
845 Sema::ActOnWhileStmt(SourceLocation WhileLoc, FullExprArg Cond,
846 Decl *CondVar, Stmt *Body) {
847 ExprResult CondResult(Cond.release());
849 VarDecl *ConditionVar = 0;
851 ConditionVar = cast<VarDecl>(CondVar);
852 CondResult = CheckConditionVariable(ConditionVar, WhileLoc, true);
853 if (CondResult.isInvalid())
856 Expr *ConditionExpr = CondResult.take();
860 DiagnoseUnusedExprResult(Body);
862 return Owned(new (Context) WhileStmt(Context, ConditionVar, ConditionExpr,
867 Sema::ActOnDoStmt(SourceLocation DoLoc, Stmt *Body,
868 SourceLocation WhileLoc, SourceLocation CondLParen,
869 Expr *Cond, SourceLocation CondRParen) {
870 assert(Cond && "ActOnDoStmt(): missing expression");
872 ExprResult CondResult = CheckBooleanCondition(Cond, DoLoc);
873 if (CondResult.isInvalid() || CondResult.isInvalid())
875 Cond = CondResult.take();
877 CheckImplicitConversions(Cond, DoLoc);
878 CondResult = MaybeCreateExprWithCleanups(Cond);
879 if (CondResult.isInvalid())
881 Cond = CondResult.take();
883 DiagnoseUnusedExprResult(Body);
885 return Owned(new (Context) DoStmt(Body, Cond, DoLoc, WhileLoc, CondRParen));
889 Sema::ActOnForStmt(SourceLocation ForLoc, SourceLocation LParenLoc,
890 Stmt *First, FullExprArg second, Decl *secondVar,
892 SourceLocation RParenLoc, Stmt *Body) {
893 if (!getLangOptions().CPlusPlus) {
894 if (DeclStmt *DS = dyn_cast_or_null<DeclStmt>(First)) {
895 // C99 6.8.5p3: The declaration part of a 'for' statement shall only
896 // declare identifiers for objects having storage class 'auto' or
898 for (DeclStmt::decl_iterator DI=DS->decl_begin(), DE=DS->decl_end();
900 VarDecl *VD = dyn_cast<VarDecl>(*DI);
901 if (VD && VD->isLocalVarDecl() && !VD->hasLocalStorage())
904 Diag((*DI)->getLocation(), diag::err_non_variable_decl_in_for);
905 // FIXME: mark decl erroneous!
910 ExprResult SecondResult(second.release());
911 VarDecl *ConditionVar = 0;
913 ConditionVar = cast<VarDecl>(secondVar);
914 SecondResult = CheckConditionVariable(ConditionVar, ForLoc, true);
915 if (SecondResult.isInvalid())
919 Expr *Third = third.release().takeAs<Expr>();
921 DiagnoseUnusedExprResult(First);
922 DiagnoseUnusedExprResult(Third);
923 DiagnoseUnusedExprResult(Body);
925 return Owned(new (Context) ForStmt(Context, First,
926 SecondResult.take(), ConditionVar,
927 Third, Body, ForLoc, LParenLoc,
931 /// In an Objective C collection iteration statement:
933 /// x can be an arbitrary l-value expression. Bind it up as a
935 StmtResult Sema::ActOnForEachLValueExpr(Expr *E) {
936 CheckImplicitConversions(E);
937 ExprResult Result = MaybeCreateExprWithCleanups(E);
938 if (Result.isInvalid()) return StmtError();
939 return Owned(static_cast<Stmt*>(Result.get()));
943 Sema::ActOnObjCForCollectionStmt(SourceLocation ForLoc,
944 SourceLocation LParenLoc,
945 Stmt *First, Expr *Second,
946 SourceLocation RParenLoc, Stmt *Body) {
949 if (DeclStmt *DS = dyn_cast<DeclStmt>(First)) {
950 if (!DS->isSingleDecl())
951 return StmtError(Diag((*DS->decl_begin())->getLocation(),
952 diag::err_toomany_element_decls));
954 Decl *D = DS->getSingleDecl();
955 FirstType = cast<ValueDecl>(D)->getType();
956 // C99 6.8.5p3: The declaration part of a 'for' statement shall only
957 // declare identifiers for objects having storage class 'auto' or
959 VarDecl *VD = cast<VarDecl>(D);
960 if (VD->isLocalVarDecl() && !VD->hasLocalStorage())
961 return StmtError(Diag(VD->getLocation(),
962 diag::err_non_variable_decl_in_for));
964 Expr *FirstE = cast<Expr>(First);
965 if (!FirstE->isTypeDependent() && !FirstE->isLValue())
966 return StmtError(Diag(First->getLocStart(),
967 diag::err_selector_element_not_lvalue)
968 << First->getSourceRange());
970 FirstType = static_cast<Expr*>(First)->getType();
972 if (!FirstType->isDependentType() &&
973 !FirstType->isObjCObjectPointerType() &&
974 !FirstType->isBlockPointerType())
975 Diag(ForLoc, diag::err_selector_element_type)
976 << FirstType << First->getSourceRange();
978 if (Second && !Second->isTypeDependent()) {
979 ExprResult Result = DefaultFunctionArrayLvalueConversion(Second);
980 if (Result.isInvalid())
982 Second = Result.take();
983 QualType SecondType = Second->getType();
984 if (!SecondType->isObjCObjectPointerType())
985 Diag(ForLoc, diag::err_collection_expr_type)
986 << SecondType << Second->getSourceRange();
987 else if (const ObjCObjectPointerType *OPT =
988 SecondType->getAsObjCInterfacePointerType()) {
989 llvm::SmallVector<IdentifierInfo *, 4> KeyIdents;
990 IdentifierInfo* selIdent =
991 &Context.Idents.get("countByEnumeratingWithState");
992 KeyIdents.push_back(selIdent);
993 selIdent = &Context.Idents.get("objects");
994 KeyIdents.push_back(selIdent);
995 selIdent = &Context.Idents.get("count");
996 KeyIdents.push_back(selIdent);
997 Selector CSelector = Context.Selectors.getSelector(3, &KeyIdents[0]);
998 if (ObjCInterfaceDecl *IDecl = OPT->getInterfaceDecl()) {
999 if (!IDecl->isForwardDecl() &&
1000 !IDecl->lookupInstanceMethod(CSelector) &&
1001 !LookupMethodInQualifiedType(CSelector, OPT, true)) {
1002 // Must further look into private implementation methods.
1003 if (!LookupPrivateInstanceMethod(CSelector, IDecl))
1004 Diag(ForLoc, diag::warn_collection_expr_type)
1005 << SecondType << CSelector << Second->getSourceRange();
1010 return Owned(new (Context) ObjCForCollectionStmt(First, Second, Body,
1011 ForLoc, RParenLoc));
1016 enum BeginEndFunction {
1021 /// Build a variable declaration for a for-range statement.
1022 static VarDecl *BuildForRangeVarDecl(Sema &SemaRef, SourceLocation Loc,
1023 QualType Type, const char *Name) {
1024 DeclContext *DC = SemaRef.CurContext;
1025 IdentifierInfo *II = &SemaRef.PP.getIdentifierTable().get(Name);
1026 TypeSourceInfo *TInfo = SemaRef.Context.getTrivialTypeSourceInfo(Type, Loc);
1027 VarDecl *Decl = VarDecl::Create(SemaRef.Context, DC, Loc, Loc, II, Type,
1028 TInfo, SC_Auto, SC_None);
1029 Decl->setImplicit();
1033 /// Finish building a variable declaration for a for-range statement.
1034 /// \return true if an error occurs.
1035 static bool FinishForRangeVarDecl(Sema &SemaRef, VarDecl *Decl, Expr *Init,
1036 SourceLocation Loc, int diag) {
1037 // Deduce the type for the iterator variable now rather than leaving it to
1038 // AddInitializerToDecl, so we can produce a more suitable diagnostic.
1039 TypeSourceInfo *InitTSI = 0;
1040 if (Init->getType()->isVoidType() ||
1041 !SemaRef.DeduceAutoType(Decl->getTypeSourceInfo(), Init, InitTSI))
1042 SemaRef.Diag(Loc, diag) << Init->getType();
1044 Decl->setInvalidDecl();
1047 Decl->setTypeSourceInfo(InitTSI);
1048 Decl->setType(InitTSI->getType());
1050 SemaRef.AddInitializerToDecl(Decl, Init, /*DirectInit=*/false,
1051 /*TypeMayContainAuto=*/false);
1052 SemaRef.FinalizeDeclaration(Decl);
1053 SemaRef.CurContext->addHiddenDecl(Decl);
1057 /// Produce a note indicating which begin/end function was implicitly called
1058 /// by a C++0x for-range statement. This is often not obvious from the code,
1059 /// nor from the diagnostics produced when analysing the implicit expressions
1060 /// required in a for-range statement.
1061 void NoteForRangeBeginEndFunction(Sema &SemaRef, Expr *E,
1062 BeginEndFunction BEF) {
1063 CallExpr *CE = dyn_cast<CallExpr>(E);
1066 FunctionDecl *D = dyn_cast<FunctionDecl>(CE->getCalleeDecl());
1069 SourceLocation Loc = D->getLocation();
1071 std::string Description;
1072 bool IsTemplate = false;
1073 if (FunctionTemplateDecl *FunTmpl = D->getPrimaryTemplate()) {
1074 Description = SemaRef.getTemplateArgumentBindingsText(
1075 FunTmpl->getTemplateParameters(), *D->getTemplateSpecializationArgs());
1079 SemaRef.Diag(Loc, diag::note_for_range_begin_end)
1080 << BEF << IsTemplate << Description << E->getType();
1083 /// Build a call to 'begin' or 'end' for a C++0x for-range statement. If the
1084 /// given LookupResult is non-empty, it is assumed to describe a member which
1085 /// will be invoked. Otherwise, the function will be found via argument
1086 /// dependent lookup.
1087 static ExprResult BuildForRangeBeginEndCall(Sema &SemaRef, Scope *S,
1090 BeginEndFunction BEF,
1091 const DeclarationNameInfo &NameInfo,
1092 LookupResult &MemberLookup,
1094 ExprResult CallExpr;
1095 if (!MemberLookup.empty()) {
1096 ExprResult MemberRef =
1097 SemaRef.BuildMemberReferenceExpr(Range, Range->getType(), Loc,
1098 /*IsPtr=*/false, CXXScopeSpec(),
1099 /*Qualifier=*/0, MemberLookup,
1100 /*TemplateArgs=*/0);
1101 if (MemberRef.isInvalid())
1103 CallExpr = SemaRef.ActOnCallExpr(S, MemberRef.get(), Loc, MultiExprArg(),
1105 if (CallExpr.isInvalid())
1108 UnresolvedSet<0> FoundNames;
1109 // C++0x [stmt.ranged]p1: For the purposes of this name lookup, namespace
1110 // std is an associated namespace.
1111 UnresolvedLookupExpr *Fn =
1112 UnresolvedLookupExpr::Create(SemaRef.Context, /*NamingClass=*/0,
1113 NestedNameSpecifierLoc(), NameInfo,
1114 /*NeedsADL=*/true, /*Overloaded=*/false,
1115 FoundNames.begin(), FoundNames.end(),
1116 /*LookInStdNamespace=*/true);
1117 CallExpr = SemaRef.BuildOverloadedCallExpr(S, Fn, Fn, Loc, &Range, 1, Loc,
1119 if (CallExpr.isInvalid()) {
1120 SemaRef.Diag(Range->getLocStart(), diag::note_for_range_type)
1121 << Range->getType();
1125 if (FinishForRangeVarDecl(SemaRef, Decl, CallExpr.get(), Loc,
1126 diag::err_for_range_iter_deduction_failure)) {
1127 NoteForRangeBeginEndFunction(SemaRef, CallExpr.get(), BEF);
1135 /// ActOnCXXForRangeStmt - Check and build a C++0x for-range statement.
1137 /// C++0x [stmt.ranged]:
1138 /// A range-based for statement is equivalent to
1141 /// auto && __range = range-init;
1142 /// for ( auto __begin = begin-expr,
1143 /// __end = end-expr;
1144 /// __begin != __end;
1146 /// for-range-declaration = *__begin;
1151 /// The body of the loop is not available yet, since it cannot be analysed until
1152 /// we have determined the type of the for-range-declaration.
1154 Sema::ActOnCXXForRangeStmt(SourceLocation ForLoc, SourceLocation LParenLoc,
1155 Stmt *First, SourceLocation ColonLoc, Expr *Range,
1156 SourceLocation RParenLoc) {
1157 if (!First || !Range)
1160 DeclStmt *DS = dyn_cast<DeclStmt>(First);
1161 assert(DS && "first part of for range not a decl stmt");
1163 if (!DS->isSingleDecl()) {
1164 Diag(DS->getStartLoc(), diag::err_type_defined_in_for_range);
1167 if (DS->getSingleDecl()->isInvalidDecl())
1170 if (DiagnoseUnexpandedParameterPack(Range, UPPC_Expression))
1173 // Build auto && __range = range-init
1174 SourceLocation RangeLoc = Range->getLocStart();
1175 VarDecl *RangeVar = BuildForRangeVarDecl(*this, RangeLoc,
1176 Context.getAutoRRefDeductType(),
1178 if (FinishForRangeVarDecl(*this, RangeVar, Range, RangeLoc,
1179 diag::err_for_range_deduction_failure))
1182 // Claim the type doesn't contain auto: we've already done the checking.
1183 DeclGroupPtrTy RangeGroup =
1184 BuildDeclaratorGroup((Decl**)&RangeVar, 1, /*TypeMayContainAuto=*/false);
1185 StmtResult RangeDecl = ActOnDeclStmt(RangeGroup, RangeLoc, RangeLoc);
1186 if (RangeDecl.isInvalid())
1189 return BuildCXXForRangeStmt(ForLoc, ColonLoc, RangeDecl.get(),
1190 /*BeginEndDecl=*/0, /*Cond=*/0, /*Inc=*/0, DS,
1194 /// BuildCXXForRangeStmt - Build or instantiate a C++0x for-range statement.
1196 Sema::BuildCXXForRangeStmt(SourceLocation ForLoc, SourceLocation ColonLoc,
1197 Stmt *RangeDecl, Stmt *BeginEnd, Expr *Cond,
1198 Expr *Inc, Stmt *LoopVarDecl,
1199 SourceLocation RParenLoc) {
1200 Scope *S = getCurScope();
1202 DeclStmt *RangeDS = cast<DeclStmt>(RangeDecl);
1203 VarDecl *RangeVar = cast<VarDecl>(RangeDS->getSingleDecl());
1204 QualType RangeVarType = RangeVar->getType();
1206 DeclStmt *LoopVarDS = cast<DeclStmt>(LoopVarDecl);
1207 VarDecl *LoopVar = cast<VarDecl>(LoopVarDS->getSingleDecl());
1209 StmtResult BeginEndDecl = BeginEnd;
1210 ExprResult NotEqExpr = Cond, IncrExpr = Inc;
1212 if (!BeginEndDecl.get() && !RangeVarType->isDependentType()) {
1213 SourceLocation RangeLoc = RangeVar->getLocation();
1215 ExprResult RangeRef = BuildDeclRefExpr(RangeVar,
1216 RangeVarType.getNonReferenceType(),
1217 VK_LValue, ColonLoc);
1218 if (RangeRef.isInvalid())
1221 QualType AutoType = Context.getAutoDeductType();
1222 Expr *Range = RangeVar->getInit();
1225 QualType RangeType = Range->getType();
1227 if (RequireCompleteType(RangeLoc, RangeType,
1228 PDiag(diag::err_for_range_incomplete_type)))
1231 // Build auto __begin = begin-expr, __end = end-expr.
1232 VarDecl *BeginVar = BuildForRangeVarDecl(*this, ColonLoc, AutoType,
1234 VarDecl *EndVar = BuildForRangeVarDecl(*this, ColonLoc, AutoType,
1237 // Build begin-expr and end-expr and attach to __begin and __end variables.
1238 ExprResult BeginExpr, EndExpr;
1239 if (const ArrayType *UnqAT = RangeType->getAsArrayTypeUnsafe()) {
1240 // - if _RangeT is an array type, begin-expr and end-expr are __range and
1241 // __range + __bound, respectively, where __bound is the array bound. If
1242 // _RangeT is an array of unknown size or an array of incomplete type,
1243 // the program is ill-formed;
1245 // begin-expr is __range.
1246 BeginExpr = RangeRef;
1247 if (FinishForRangeVarDecl(*this, BeginVar, RangeRef.get(), ColonLoc,
1248 diag::err_for_range_iter_deduction_failure)) {
1249 NoteForRangeBeginEndFunction(*this, BeginExpr.get(), BEF_begin);
1253 // Find the array bound.
1254 ExprResult BoundExpr;
1255 if (const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(UnqAT))
1256 BoundExpr = Owned(IntegerLiteral::Create(Context, CAT->getSize(),
1257 Context.getPointerDiffType(),
1259 else if (const VariableArrayType *VAT =
1260 dyn_cast<VariableArrayType>(UnqAT))
1261 BoundExpr = VAT->getSizeExpr();
1263 // Can't be a DependentSizedArrayType or an IncompleteArrayType since
1264 // UnqAT is not incomplete and Range is not type-dependent.
1265 assert(0 && "Unexpected array type in for-range");
1269 // end-expr is __range + __bound.
1270 EndExpr = ActOnBinOp(S, ColonLoc, tok::plus, RangeRef.get(),
1272 if (EndExpr.isInvalid())
1274 if (FinishForRangeVarDecl(*this, EndVar, EndExpr.get(), ColonLoc,
1275 diag::err_for_range_iter_deduction_failure)) {
1276 NoteForRangeBeginEndFunction(*this, EndExpr.get(), BEF_end);
1280 DeclarationNameInfo BeginNameInfo(&PP.getIdentifierTable().get("begin"),
1282 DeclarationNameInfo EndNameInfo(&PP.getIdentifierTable().get("end"),
1285 LookupResult BeginMemberLookup(*this, BeginNameInfo, LookupMemberName);
1286 LookupResult EndMemberLookup(*this, EndNameInfo, LookupMemberName);
1288 if (CXXRecordDecl *D = RangeType->getAsCXXRecordDecl()) {
1289 // - if _RangeT is a class type, the unqualified-ids begin and end are
1290 // looked up in the scope of class _RangeT as if by class member access
1291 // lookup (3.4.5), and if either (or both) finds at least one
1292 // declaration, begin-expr and end-expr are __range.begin() and
1293 // __range.end(), respectively;
1294 LookupQualifiedName(BeginMemberLookup, D);
1295 LookupQualifiedName(EndMemberLookup, D);
1297 if (BeginMemberLookup.empty() != EndMemberLookup.empty()) {
1298 Diag(ColonLoc, diag::err_for_range_member_begin_end_mismatch)
1299 << RangeType << BeginMemberLookup.empty();
1303 // - otherwise, begin-expr and end-expr are begin(__range) and
1304 // end(__range), respectively, where begin and end are looked up with
1305 // argument-dependent lookup (3.4.2). For the purposes of this name
1306 // lookup, namespace std is an associated namespace.
1309 BeginExpr = BuildForRangeBeginEndCall(*this, S, ColonLoc, BeginVar,
1310 BEF_begin, BeginNameInfo,
1311 BeginMemberLookup, RangeRef.get());
1312 if (BeginExpr.isInvalid())
1315 EndExpr = BuildForRangeBeginEndCall(*this, S, ColonLoc, EndVar,
1316 BEF_end, EndNameInfo,
1317 EndMemberLookup, RangeRef.get());
1318 if (EndExpr.isInvalid())
1322 // C++0x [decl.spec.auto]p6: BeginType and EndType must be the same.
1323 QualType BeginType = BeginVar->getType(), EndType = EndVar->getType();
1324 if (!Context.hasSameType(BeginType, EndType)) {
1325 Diag(RangeLoc, diag::err_for_range_begin_end_types_differ)
1326 << BeginType << EndType;
1327 NoteForRangeBeginEndFunction(*this, BeginExpr.get(), BEF_begin);
1328 NoteForRangeBeginEndFunction(*this, EndExpr.get(), BEF_end);
1331 Decl *BeginEndDecls[] = { BeginVar, EndVar };
1332 // Claim the type doesn't contain auto: we've already done the checking.
1333 DeclGroupPtrTy BeginEndGroup =
1334 BuildDeclaratorGroup(BeginEndDecls, 2, /*TypeMayContainAuto=*/false);
1335 BeginEndDecl = ActOnDeclStmt(BeginEndGroup, ColonLoc, ColonLoc);
1337 ExprResult BeginRef = BuildDeclRefExpr(BeginVar,
1338 BeginType.getNonReferenceType(),
1339 VK_LValue, ColonLoc);
1340 ExprResult EndRef = BuildDeclRefExpr(EndVar, EndType.getNonReferenceType(),
1341 VK_LValue, ColonLoc);
1343 // Build and check __begin != __end expression.
1344 NotEqExpr = ActOnBinOp(S, ColonLoc, tok::exclaimequal,
1345 BeginRef.get(), EndRef.get());
1346 NotEqExpr = ActOnBooleanCondition(S, ColonLoc, NotEqExpr.get());
1347 NotEqExpr = ActOnFinishFullExpr(NotEqExpr.get());
1348 if (NotEqExpr.isInvalid()) {
1349 NoteForRangeBeginEndFunction(*this, BeginExpr.get(), BEF_begin);
1350 if (!Context.hasSameType(BeginType, EndType))
1351 NoteForRangeBeginEndFunction(*this, EndExpr.get(), BEF_end);
1355 // Build and check ++__begin expression.
1356 IncrExpr = ActOnUnaryOp(S, ColonLoc, tok::plusplus, BeginRef.get());
1357 IncrExpr = ActOnFinishFullExpr(IncrExpr.get());
1358 if (IncrExpr.isInvalid()) {
1359 NoteForRangeBeginEndFunction(*this, BeginExpr.get(), BEF_begin);
1363 // Build and check *__begin expression.
1364 ExprResult DerefExpr = ActOnUnaryOp(S, ColonLoc, tok::star, BeginRef.get());
1365 if (DerefExpr.isInvalid()) {
1366 NoteForRangeBeginEndFunction(*this, BeginExpr.get(), BEF_begin);
1370 // Attach *__begin as initializer for VD.
1371 if (!LoopVar->isInvalidDecl()) {
1372 AddInitializerToDecl(LoopVar, DerefExpr.get(), /*DirectInit=*/false,
1373 /*TypeMayContainAuto=*/true);
1374 if (LoopVar->isInvalidDecl())
1375 NoteForRangeBeginEndFunction(*this, BeginExpr.get(), BEF_begin);
1379 return Owned(new (Context) CXXForRangeStmt(RangeDS,
1380 cast_or_null<DeclStmt>(BeginEndDecl.get()),
1381 NotEqExpr.take(), IncrExpr.take(),
1382 LoopVarDS, /*Body=*/0, ForLoc,
1383 ColonLoc, RParenLoc));
1386 /// FinishCXXForRangeStmt - Attach the body to a C++0x for-range statement.
1387 /// This is a separate step from ActOnCXXForRangeStmt because analysis of the
1388 /// body cannot be performed until after the type of the range variable is
1390 StmtResult Sema::FinishCXXForRangeStmt(Stmt *S, Stmt *B) {
1394 cast<CXXForRangeStmt>(S)->setBody(B);
1398 StmtResult Sema::ActOnGotoStmt(SourceLocation GotoLoc,
1399 SourceLocation LabelLoc,
1400 LabelDecl *TheDecl) {
1401 getCurFunction()->setHasBranchIntoScope();
1403 return Owned(new (Context) GotoStmt(TheDecl, GotoLoc, LabelLoc));
1407 Sema::ActOnIndirectGotoStmt(SourceLocation GotoLoc, SourceLocation StarLoc,
1409 // Convert operand to void*
1410 if (!E->isTypeDependent()) {
1411 QualType ETy = E->getType();
1412 QualType DestTy = Context.getPointerType(Context.VoidTy.withConst());
1413 ExprResult ExprRes = Owned(E);
1414 AssignConvertType ConvTy =
1415 CheckSingleAssignmentConstraints(DestTy, ExprRes);
1416 if (ExprRes.isInvalid())
1419 if (DiagnoseAssignmentResult(ConvTy, StarLoc, DestTy, ETy, E, AA_Passing))
1423 getCurFunction()->setHasIndirectGoto();
1425 return Owned(new (Context) IndirectGotoStmt(GotoLoc, StarLoc, E));
1429 Sema::ActOnContinueStmt(SourceLocation ContinueLoc, Scope *CurScope) {
1430 Scope *S = CurScope->getContinueParent();
1432 // C99 6.8.6.2p1: A break shall appear only in or as a loop body.
1433 return StmtError(Diag(ContinueLoc, diag::err_continue_not_in_loop));
1436 return Owned(new (Context) ContinueStmt(ContinueLoc));
1440 Sema::ActOnBreakStmt(SourceLocation BreakLoc, Scope *CurScope) {
1441 Scope *S = CurScope->getBreakParent();
1443 // C99 6.8.6.3p1: A break shall appear only in or as a switch/loop body.
1444 return StmtError(Diag(BreakLoc, diag::err_break_not_in_loop_or_switch));
1447 return Owned(new (Context) BreakStmt(BreakLoc));
1450 /// \brief Determine whether the given expression is a candidate for
1451 /// copy elision in either a return statement or a throw expression.
1453 /// \param ReturnType If we're determining the copy elision candidate for
1454 /// a return statement, this is the return type of the function. If we're
1455 /// determining the copy elision candidate for a throw expression, this will
1458 /// \param E The expression being returned from the function or block, or
1461 /// \param AllowFunctionParameter Whether we allow function parameters to
1462 /// be considered NRVO candidates. C++ prohibits this for NRVO itself, but
1463 /// we re-use this logic to determine whether we should try to move as part of
1464 /// a return or throw (which does allow function parameters).
1466 /// \returns The NRVO candidate variable, if the return statement may use the
1467 /// NRVO, or NULL if there is no such candidate.
1468 const VarDecl *Sema::getCopyElisionCandidate(QualType ReturnType,
1470 bool AllowFunctionParameter) {
1471 QualType ExprType = E->getType();
1472 // - in a return statement in a function with ...
1473 // ... a class return type ...
1474 if (!ReturnType.isNull()) {
1475 if (!ReturnType->isRecordType())
1477 // ... the same cv-unqualified type as the function return type ...
1478 if (!Context.hasSameUnqualifiedType(ReturnType, ExprType))
1482 // ... the expression is the name of a non-volatile automatic object
1483 // (other than a function or catch-clause parameter)) ...
1484 const DeclRefExpr *DR = dyn_cast<DeclRefExpr>(E->IgnoreParens());
1487 const VarDecl *VD = dyn_cast<VarDecl>(DR->getDecl());
1491 if (VD->hasLocalStorage() && !VD->isExceptionVariable() &&
1492 !VD->getType()->isReferenceType() && !VD->hasAttr<BlocksAttr>() &&
1493 !VD->getType().isVolatileQualified() &&
1494 ((VD->getKind() == Decl::Var) ||
1495 (AllowFunctionParameter && VD->getKind() == Decl::ParmVar)))
1501 /// \brief Perform the initialization of a potentially-movable value, which
1502 /// is the result of return value.
1504 /// This routine implements C++0x [class.copy]p33, which attempts to treat
1505 /// returned lvalues as rvalues in certain cases (to prefer move construction),
1506 /// then falls back to treating them as lvalues if that failed.
1508 Sema::PerformMoveOrCopyInitialization(const InitializedEntity &Entity,
1509 const VarDecl *NRVOCandidate,
1510 QualType ResultType,
1512 // C++0x [class.copy]p33:
1513 // When the criteria for elision of a copy operation are met or would
1514 // be met save for the fact that the source object is a function
1515 // parameter, and the object to be copied is designated by an lvalue,
1516 // overload resolution to select the constructor for the copy is first
1517 // performed as if the object were designated by an rvalue.
1518 ExprResult Res = ExprError();
1519 if (NRVOCandidate || getCopyElisionCandidate(ResultType, Value, true)) {
1520 ImplicitCastExpr AsRvalue(ImplicitCastExpr::OnStack,
1521 Value->getType(), CK_LValueToRValue,
1524 Expr *InitExpr = &AsRvalue;
1525 InitializationKind Kind
1526 = InitializationKind::CreateCopy(Value->getLocStart(),
1527 Value->getLocStart());
1528 InitializationSequence Seq(*this, Entity, Kind, &InitExpr, 1);
1530 // [...] If overload resolution fails, or if the type of the first
1531 // parameter of the selected constructor is not an rvalue reference
1532 // to the object's type (possibly cv-qualified), overload resolution
1533 // is performed again, considering the object as an lvalue.
1535 for (InitializationSequence::step_iterator Step = Seq.step_begin(),
1536 StepEnd = Seq.step_end();
1537 Step != StepEnd; ++Step) {
1538 if (Step->Kind != InitializationSequence::SK_ConstructorInitialization)
1541 CXXConstructorDecl *Constructor
1542 = cast<CXXConstructorDecl>(Step->Function.Function);
1544 const RValueReferenceType *RRefType
1545 = Constructor->getParamDecl(0)->getType()
1546 ->getAs<RValueReferenceType>();
1548 // If we don't meet the criteria, break out now.
1550 !Context.hasSameUnqualifiedType(RRefType->getPointeeType(),
1551 Context.getTypeDeclType(Constructor->getParent())))
1554 // Promote "AsRvalue" to the heap, since we now need this
1555 // expression node to persist.
1556 Value = ImplicitCastExpr::Create(Context, Value->getType(),
1557 CK_LValueToRValue, Value, 0,
1560 // Complete type-checking the initialization of the return type
1561 // using the constructor we found.
1562 Res = Seq.Perform(*this, Entity, Kind, MultiExprArg(&Value, 1));
1567 // Either we didn't meet the criteria for treating an lvalue as an rvalue,
1568 // above, or overload resolution failed. Either way, we need to try
1569 // (again) now with the return value expression as written.
1570 if (Res.isInvalid())
1571 Res = PerformCopyInitialization(Entity, SourceLocation(), Value);
1576 /// ActOnBlockReturnStmt - Utility routine to figure out block's return type.
1579 Sema::ActOnBlockReturnStmt(SourceLocation ReturnLoc, Expr *RetValExp) {
1580 // If this is the first return we've seen in the block, infer the type of
1581 // the block from it.
1582 BlockScopeInfo *CurBlock = getCurBlock();
1583 if (CurBlock->ReturnType.isNull()) {
1585 // Don't call UsualUnaryConversions(), since we don't want to do
1586 // integer promotions here.
1587 ExprResult Result = DefaultFunctionArrayLvalueConversion(RetValExp);
1588 if (Result.isInvalid())
1590 RetValExp = Result.take();
1592 if (!RetValExp->isTypeDependent()) {
1593 CurBlock->ReturnType = RetValExp->getType();
1594 if (BlockDeclRefExpr *CDRE = dyn_cast<BlockDeclRefExpr>(RetValExp)) {
1595 // We have to remove a 'const' added to copied-in variable which was
1596 // part of the implementation spec. and not the actual qualifier for
1598 if (CDRE->isConstQualAdded())
1599 CurBlock->ReturnType.removeLocalConst(); // FIXME: local???
1602 CurBlock->ReturnType = Context.DependentTy;
1604 CurBlock->ReturnType = Context.VoidTy;
1606 QualType FnRetType = CurBlock->ReturnType;
1608 if (CurBlock->FunctionType->getAs<FunctionType>()->getNoReturnAttr()) {
1609 Diag(ReturnLoc, diag::err_noreturn_block_has_return_expr)
1610 << getCurFunctionOrMethodDecl()->getDeclName();
1614 // Otherwise, verify that this result type matches the previous one. We are
1615 // pickier with blocks than for normal functions because we don't have GCC
1616 // compatibility to worry about here.
1617 ReturnStmt *Result = 0;
1618 if (CurBlock->ReturnType->isVoidType()) {
1619 if (RetValExp && !RetValExp->isTypeDependent() &&
1620 (!getLangOptions().CPlusPlus || !RetValExp->getType()->isVoidType())) {
1621 Diag(ReturnLoc, diag::err_return_block_has_expr);
1624 Result = new (Context) ReturnStmt(ReturnLoc, RetValExp, 0);
1625 } else if (!RetValExp) {
1626 if (!CurBlock->ReturnType->isDependentType())
1627 return StmtError(Diag(ReturnLoc, diag::err_block_return_missing_expr));
1629 Result = new (Context) ReturnStmt(ReturnLoc, 0, 0);
1631 const VarDecl *NRVOCandidate = 0;
1633 if (!FnRetType->isDependentType() && !RetValExp->isTypeDependent()) {
1634 // we have a non-void block with an expression, continue checking
1636 // C99 6.8.6.4p3(136): The return statement is not an assignment. The
1637 // overlap restriction of subclause 6.5.16.1 does not apply to the case of
1640 // In C++ the return statement is handled via a copy initialization.
1641 // the C version of which boils down to CheckSingleAssignmentConstraints.
1642 NRVOCandidate = getCopyElisionCandidate(FnRetType, RetValExp, false);
1643 InitializedEntity Entity = InitializedEntity::InitializeResult(ReturnLoc,
1645 NRVOCandidate != 0);
1646 ExprResult Res = PerformMoveOrCopyInitialization(Entity, NRVOCandidate,
1647 FnRetType, RetValExp);
1648 if (Res.isInvalid()) {
1649 // FIXME: Cleanup temporaries here, anyway?
1654 CheckImplicitConversions(RetValExp, ReturnLoc);
1655 RetValExp = MaybeCreateExprWithCleanups(RetValExp);
1658 RetValExp = Res.takeAs<Expr>();
1660 CheckReturnStackAddr(RetValExp, FnRetType, ReturnLoc);
1663 Result = new (Context) ReturnStmt(ReturnLoc, RetValExp, NRVOCandidate);
1666 // If we need to check for the named return value optimization, save the
1667 // return statement in our scope for later processing.
1668 if (getLangOptions().CPlusPlus && FnRetType->isRecordType() &&
1669 !CurContext->isDependentContext())
1670 FunctionScopes.back()->Returns.push_back(Result);
1672 return Owned(Result);
1676 Sema::ActOnReturnStmt(SourceLocation ReturnLoc, Expr *RetValExp) {
1677 // Check for unexpanded parameter packs.
1678 if (RetValExp && DiagnoseUnexpandedParameterPack(RetValExp))
1682 return ActOnBlockReturnStmt(ReturnLoc, RetValExp);
1685 QualType DeclaredRetType;
1686 if (const FunctionDecl *FD = getCurFunctionDecl()) {
1687 FnRetType = FD->getResultType();
1688 DeclaredRetType = FnRetType;
1689 if (FD->hasAttr<NoReturnAttr>() ||
1690 FD->getType()->getAs<FunctionType>()->getNoReturnAttr())
1691 Diag(ReturnLoc, diag::warn_noreturn_function_has_return_expr)
1692 << getCurFunctionOrMethodDecl()->getDeclName();
1693 } else if (ObjCMethodDecl *MD = getCurMethodDecl()) {
1694 DeclaredRetType = MD->getResultType();
1695 if (MD->hasRelatedResultType() && MD->getClassInterface()) {
1696 // In the implementation of a method with a related return type, the
1697 // type used to type-check the validity of return statements within the
1698 // method body is a pointer to the type of the class being implemented.
1699 FnRetType = Context.getObjCInterfaceType(MD->getClassInterface());
1700 FnRetType = Context.getObjCObjectPointerType(FnRetType);
1702 FnRetType = DeclaredRetType;
1704 } else // If we don't have a function/method context, bail.
1707 ReturnStmt *Result = 0;
1708 if (FnRetType->isVoidType()) {
1710 if (!RetValExp->isTypeDependent()) {
1711 // C99 6.8.6.4p1 (ext_ since GCC warns)
1712 unsigned D = diag::ext_return_has_expr;
1713 if (RetValExp->getType()->isVoidType())
1714 D = diag::ext_return_has_void_expr;
1716 ExprResult Result = Owned(RetValExp);
1717 Result = IgnoredValueConversions(Result.take());
1718 if (Result.isInvalid())
1720 RetValExp = Result.take();
1721 RetValExp = ImpCastExprToType(RetValExp,
1722 Context.VoidTy, CK_ToVoid).take();
1725 // return (some void expression); is legal in C++.
1726 if (D != diag::ext_return_has_void_expr ||
1727 !getLangOptions().CPlusPlus) {
1728 NamedDecl *CurDecl = getCurFunctionOrMethodDecl();
1730 << CurDecl->getDeclName() << isa<ObjCMethodDecl>(CurDecl)
1731 << RetValExp->getSourceRange();
1735 CheckImplicitConversions(RetValExp, ReturnLoc);
1736 RetValExp = MaybeCreateExprWithCleanups(RetValExp);
1739 Result = new (Context) ReturnStmt(ReturnLoc, RetValExp, 0);
1740 } else if (!RetValExp && !FnRetType->isDependentType()) {
1741 unsigned DiagID = diag::warn_return_missing_expr; // C90 6.6.6.4p4
1742 // C99 6.8.6.4p1 (ext_ since GCC warns)
1743 if (getLangOptions().C99) DiagID = diag::ext_return_missing_expr;
1745 if (FunctionDecl *FD = getCurFunctionDecl())
1746 Diag(ReturnLoc, DiagID) << FD->getIdentifier() << 0/*fn*/;
1748 Diag(ReturnLoc, DiagID) << getCurMethodDecl()->getDeclName() << 1/*meth*/;
1749 Result = new (Context) ReturnStmt(ReturnLoc);
1751 const VarDecl *NRVOCandidate = 0;
1752 if (!FnRetType->isDependentType() && !RetValExp->isTypeDependent()) {
1753 // we have a non-void function with an expression, continue checking
1755 // C99 6.8.6.4p3(136): The return statement is not an assignment. The
1756 // overlap restriction of subclause 6.5.16.1 does not apply to the case of
1759 // In C++ the return statement is handled via a copy initialization.
1760 // the C version of which boils down to CheckSingleAssignmentConstraints.
1761 NRVOCandidate = getCopyElisionCandidate(FnRetType, RetValExp, false);
1762 InitializedEntity Entity = InitializedEntity::InitializeResult(ReturnLoc,
1764 NRVOCandidate != 0);
1765 ExprResult Res = PerformMoveOrCopyInitialization(Entity, NRVOCandidate,
1766 FnRetType, RetValExp);
1767 if (Res.isInvalid()) {
1768 // FIXME: Cleanup temporaries here, anyway?
1772 RetValExp = Res.takeAs<Expr>();
1774 CheckReturnStackAddr(RetValExp, FnRetType, ReturnLoc);
1778 // If we type-checked an Objective-C method's return type based
1779 // on a related return type, we may need to adjust the return
1780 // type again. Do so now.
1781 if (DeclaredRetType != FnRetType) {
1782 ExprResult result = PerformImplicitConversion(RetValExp,
1785 if (result.isInvalid()) return StmtError();
1786 RetValExp = result.take();
1789 CheckImplicitConversions(RetValExp, ReturnLoc);
1790 RetValExp = MaybeCreateExprWithCleanups(RetValExp);
1792 Result = new (Context) ReturnStmt(ReturnLoc, RetValExp, NRVOCandidate);
1795 // If we need to check for the named return value optimization, save the
1796 // return statement in our scope for later processing.
1797 if (getLangOptions().CPlusPlus && FnRetType->isRecordType() &&
1798 !CurContext->isDependentContext())
1799 FunctionScopes.back()->Returns.push_back(Result);
1801 return Owned(Result);
1804 /// CheckAsmLValue - GNU C has an extremely ugly extension whereby they silently
1805 /// ignore "noop" casts in places where an lvalue is required by an inline asm.
1806 /// We emulate this behavior when -fheinous-gnu-extensions is specified, but
1807 /// provide a strong guidance to not use it.
1809 /// This method checks to see if the argument is an acceptable l-value and
1810 /// returns false if it is a case we can handle.
1811 static bool CheckAsmLValue(const Expr *E, Sema &S) {
1812 // Type dependent expressions will be checked during instantiation.
1813 if (E->isTypeDependent())
1817 return false; // Cool, this is an lvalue.
1819 // Okay, this is not an lvalue, but perhaps it is the result of a cast that we
1820 // are supposed to allow.
1821 const Expr *E2 = E->IgnoreParenNoopCasts(S.Context);
1822 if (E != E2 && E2->isLValue()) {
1823 if (!S.getLangOptions().HeinousExtensions)
1824 S.Diag(E2->getLocStart(), diag::err_invalid_asm_cast_lvalue)
1825 << E->getSourceRange();
1827 S.Diag(E2->getLocStart(), diag::warn_invalid_asm_cast_lvalue)
1828 << E->getSourceRange();
1829 // Accept, even if we emitted an error diagnostic.
1833 // None of the above, just randomly invalid non-lvalue.
1837 /// isOperandMentioned - Return true if the specified operand # is mentioned
1838 /// anywhere in the decomposed asm string.
1839 static bool isOperandMentioned(unsigned OpNo,
1840 llvm::ArrayRef<AsmStmt::AsmStringPiece> AsmStrPieces) {
1841 for (unsigned p = 0, e = AsmStrPieces.size(); p != e; ++p) {
1842 const AsmStmt::AsmStringPiece &Piece = AsmStrPieces[p];
1843 if (!Piece.isOperand()) continue;
1845 // If this is a reference to the input and if the input was the smaller
1846 // one, then we have to reject this asm.
1847 if (Piece.getOperandNo() == OpNo)
1854 StmtResult Sema::ActOnAsmStmt(SourceLocation AsmLoc, bool IsSimple,
1855 bool IsVolatile, unsigned NumOutputs,
1856 unsigned NumInputs, IdentifierInfo **Names,
1857 MultiExprArg constraints, MultiExprArg exprs,
1858 Expr *asmString, MultiExprArg clobbers,
1859 SourceLocation RParenLoc, bool MSAsm) {
1860 unsigned NumClobbers = clobbers.size();
1861 StringLiteral **Constraints =
1862 reinterpret_cast<StringLiteral**>(constraints.get());
1863 Expr **Exprs = exprs.get();
1864 StringLiteral *AsmString = cast<StringLiteral>(asmString);
1865 StringLiteral **Clobbers = reinterpret_cast<StringLiteral**>(clobbers.get());
1867 llvm::SmallVector<TargetInfo::ConstraintInfo, 4> OutputConstraintInfos;
1869 // The parser verifies that there is a string literal here.
1870 if (AsmString->isWide())
1871 return StmtError(Diag(AsmString->getLocStart(),diag::err_asm_wide_character)
1872 << AsmString->getSourceRange());
1874 for (unsigned i = 0; i != NumOutputs; i++) {
1875 StringLiteral *Literal = Constraints[i];
1876 if (Literal->isWide())
1877 return StmtError(Diag(Literal->getLocStart(),diag::err_asm_wide_character)
1878 << Literal->getSourceRange());
1880 llvm::StringRef OutputName;
1882 OutputName = Names[i]->getName();
1884 TargetInfo::ConstraintInfo Info(Literal->getString(), OutputName);
1885 if (!Context.Target.validateOutputConstraint(Info))
1886 return StmtError(Diag(Literal->getLocStart(),
1887 diag::err_asm_invalid_output_constraint)
1888 << Info.getConstraintStr());
1890 // Check that the output exprs are valid lvalues.
1891 Expr *OutputExpr = Exprs[i];
1892 if (CheckAsmLValue(OutputExpr, *this)) {
1893 return StmtError(Diag(OutputExpr->getLocStart(),
1894 diag::err_asm_invalid_lvalue_in_output)
1895 << OutputExpr->getSourceRange());
1898 OutputConstraintInfos.push_back(Info);
1901 llvm::SmallVector<TargetInfo::ConstraintInfo, 4> InputConstraintInfos;
1903 for (unsigned i = NumOutputs, e = NumOutputs + NumInputs; i != e; i++) {
1904 StringLiteral *Literal = Constraints[i];
1905 if (Literal->isWide())
1906 return StmtError(Diag(Literal->getLocStart(),diag::err_asm_wide_character)
1907 << Literal->getSourceRange());
1909 llvm::StringRef InputName;
1911 InputName = Names[i]->getName();
1913 TargetInfo::ConstraintInfo Info(Literal->getString(), InputName);
1914 if (!Context.Target.validateInputConstraint(OutputConstraintInfos.data(),
1915 NumOutputs, Info)) {
1916 return StmtError(Diag(Literal->getLocStart(),
1917 diag::err_asm_invalid_input_constraint)
1918 << Info.getConstraintStr());
1921 Expr *InputExpr = Exprs[i];
1923 // Only allow void types for memory constraints.
1924 if (Info.allowsMemory() && !Info.allowsRegister()) {
1925 if (CheckAsmLValue(InputExpr, *this))
1926 return StmtError(Diag(InputExpr->getLocStart(),
1927 diag::err_asm_invalid_lvalue_in_input)
1928 << Info.getConstraintStr()
1929 << InputExpr->getSourceRange());
1932 if (Info.allowsRegister()) {
1933 if (InputExpr->getType()->isVoidType()) {
1934 return StmtError(Diag(InputExpr->getLocStart(),
1935 diag::err_asm_invalid_type_in_input)
1936 << InputExpr->getType() << Info.getConstraintStr()
1937 << InputExpr->getSourceRange());
1941 ExprResult Result = DefaultFunctionArrayLvalueConversion(Exprs[i]);
1942 if (Result.isInvalid())
1945 Exprs[i] = Result.take();
1946 InputConstraintInfos.push_back(Info);
1949 // Check that the clobbers are valid.
1950 for (unsigned i = 0; i != NumClobbers; i++) {
1951 StringLiteral *Literal = Clobbers[i];
1952 if (Literal->isWide())
1953 return StmtError(Diag(Literal->getLocStart(),diag::err_asm_wide_character)
1954 << Literal->getSourceRange());
1956 llvm::StringRef Clobber = Literal->getString();
1958 if (!Context.Target.isValidGCCRegisterName(Clobber))
1959 return StmtError(Diag(Literal->getLocStart(),
1960 diag::err_asm_unknown_register_name) << Clobber);
1964 new (Context) AsmStmt(Context, AsmLoc, IsSimple, IsVolatile, MSAsm,
1965 NumOutputs, NumInputs, Names, Constraints, Exprs,
1966 AsmString, NumClobbers, Clobbers, RParenLoc);
1967 // Validate the asm string, ensuring it makes sense given the operands we
1969 llvm::SmallVector<AsmStmt::AsmStringPiece, 8> Pieces;
1971 if (unsigned DiagID = NS->AnalyzeAsmString(Pieces, Context, DiagOffs)) {
1972 Diag(getLocationOfStringLiteralByte(AsmString, DiagOffs), DiagID)
1973 << AsmString->getSourceRange();
1977 // Validate tied input operands for type mismatches.
1978 for (unsigned i = 0, e = InputConstraintInfos.size(); i != e; ++i) {
1979 TargetInfo::ConstraintInfo &Info = InputConstraintInfos[i];
1981 // If this is a tied constraint, verify that the output and input have
1982 // either exactly the same type, or that they are int/ptr operands with the
1983 // same size (int/long, int*/long, are ok etc).
1984 if (!Info.hasTiedOperand()) continue;
1986 unsigned TiedTo = Info.getTiedOperand();
1987 unsigned InputOpNo = i+NumOutputs;
1988 Expr *OutputExpr = Exprs[TiedTo];
1989 Expr *InputExpr = Exprs[InputOpNo];
1990 QualType InTy = InputExpr->getType();
1991 QualType OutTy = OutputExpr->getType();
1992 if (Context.hasSameType(InTy, OutTy))
1993 continue; // All types can be tied to themselves.
1995 // Decide if the input and output are in the same domain (integer/ptr or
1998 AD_Int, AD_FP, AD_Other
1999 } InputDomain, OutputDomain;
2001 if (InTy->isIntegerType() || InTy->isPointerType())
2002 InputDomain = AD_Int;
2003 else if (InTy->isRealFloatingType())
2004 InputDomain = AD_FP;
2006 InputDomain = AD_Other;
2008 if (OutTy->isIntegerType() || OutTy->isPointerType())
2009 OutputDomain = AD_Int;
2010 else if (OutTy->isRealFloatingType())
2011 OutputDomain = AD_FP;
2013 OutputDomain = AD_Other;
2015 // They are ok if they are the same size and in the same domain. This
2016 // allows tying things like:
2018 // void* to int if they are the same size.
2019 // double to long double if they are the same size.
2021 uint64_t OutSize = Context.getTypeSize(OutTy);
2022 uint64_t InSize = Context.getTypeSize(InTy);
2023 if (OutSize == InSize && InputDomain == OutputDomain &&
2024 InputDomain != AD_Other)
2027 // If the smaller input/output operand is not mentioned in the asm string,
2028 // then we can promote the smaller one to a larger input and the asm string
2030 bool SmallerValueMentioned = false;
2032 // If this is a reference to the input and if the input was the smaller
2033 // one, then we have to reject this asm.
2034 if (isOperandMentioned(InputOpNo, Pieces)) {
2035 // This is a use in the asm string of the smaller operand. Since we
2036 // codegen this by promoting to a wider value, the asm will get printed
2038 SmallerValueMentioned |= InSize < OutSize;
2040 if (isOperandMentioned(TiedTo, Pieces)) {
2041 // If this is a reference to the output, and if the output is the larger
2042 // value, then it's ok because we'll promote the input to the larger type.
2043 SmallerValueMentioned |= OutSize < InSize;
2046 // If the smaller value wasn't mentioned in the asm string, and if the
2047 // output was a register, just extend the shorter one to the size of the
2049 if (!SmallerValueMentioned && InputDomain != AD_Other &&
2050 OutputConstraintInfos[TiedTo].allowsRegister())
2053 // Either both of the operands were mentioned or the smaller one was
2054 // mentioned. One more special case that we'll allow: if the tied input is
2055 // integer, unmentioned, and is a constant, then we'll allow truncating it
2056 // down to the size of the destination.
2057 if (InputDomain == AD_Int && OutputDomain == AD_Int &&
2058 !isOperandMentioned(InputOpNo, Pieces) &&
2059 InputExpr->isEvaluatable(Context)) {
2061 (OutTy->isBooleanType() ? CK_IntegralToBoolean : CK_IntegralCast);
2062 InputExpr = ImpCastExprToType(InputExpr, OutTy, castKind).take();
2063 Exprs[InputOpNo] = InputExpr;
2064 NS->setInputExpr(i, InputExpr);
2068 Diag(InputExpr->getLocStart(),
2069 diag::err_asm_tying_incompatible_types)
2070 << InTy << OutTy << OutputExpr->getSourceRange()
2071 << InputExpr->getSourceRange();
2079 Sema::ActOnObjCAtCatchStmt(SourceLocation AtLoc,
2080 SourceLocation RParen, Decl *Parm,
2082 VarDecl *Var = cast_or_null<VarDecl>(Parm);
2083 if (Var && Var->isInvalidDecl())
2086 return Owned(new (Context) ObjCAtCatchStmt(AtLoc, RParen, Var, Body));
2090 Sema::ActOnObjCAtFinallyStmt(SourceLocation AtLoc, Stmt *Body) {
2091 return Owned(new (Context) ObjCAtFinallyStmt(AtLoc, Body));
2095 Sema::ActOnObjCAtTryStmt(SourceLocation AtLoc, Stmt *Try,
2096 MultiStmtArg CatchStmts, Stmt *Finally) {
2097 if (!getLangOptions().ObjCExceptions)
2098 Diag(AtLoc, diag::err_objc_exceptions_disabled) << "@try";
2100 getCurFunction()->setHasBranchProtectedScope();
2101 unsigned NumCatchStmts = CatchStmts.size();
2102 return Owned(ObjCAtTryStmt::Create(Context, AtLoc, Try,
2103 CatchStmts.release(),
2108 StmtResult Sema::BuildObjCAtThrowStmt(SourceLocation AtLoc,
2111 ExprResult Result = DefaultLvalueConversion(Throw);
2112 if (Result.isInvalid())
2115 Throw = Result.take();
2116 QualType ThrowType = Throw->getType();
2117 // Make sure the expression type is an ObjC pointer or "void *".
2118 if (!ThrowType->isDependentType() &&
2119 !ThrowType->isObjCObjectPointerType()) {
2120 const PointerType *PT = ThrowType->getAs<PointerType>();
2121 if (!PT || !PT->getPointeeType()->isVoidType())
2122 return StmtError(Diag(AtLoc, diag::error_objc_throw_expects_object)
2123 << Throw->getType() << Throw->getSourceRange());
2127 return Owned(new (Context) ObjCAtThrowStmt(AtLoc, Throw));
2131 Sema::ActOnObjCAtThrowStmt(SourceLocation AtLoc, Expr *Throw,
2133 if (!getLangOptions().ObjCExceptions)
2134 Diag(AtLoc, diag::err_objc_exceptions_disabled) << "@throw";
2137 // @throw without an expression designates a rethrow (which much occur
2138 // in the context of an @catch clause).
2139 Scope *AtCatchParent = CurScope;
2140 while (AtCatchParent && !AtCatchParent->isAtCatchScope())
2141 AtCatchParent = AtCatchParent->getParent();
2143 return StmtError(Diag(AtLoc, diag::error_rethrow_used_outside_catch));
2146 return BuildObjCAtThrowStmt(AtLoc, Throw);
2150 Sema::ActOnObjCAtSynchronizedStmt(SourceLocation AtLoc, Expr *SyncExpr,
2152 getCurFunction()->setHasBranchProtectedScope();
2154 ExprResult Result = DefaultLvalueConversion(SyncExpr);
2155 if (Result.isInvalid())
2158 SyncExpr = Result.take();
2159 // Make sure the expression type is an ObjC pointer or "void *".
2160 if (!SyncExpr->getType()->isDependentType() &&
2161 !SyncExpr->getType()->isObjCObjectPointerType()) {
2162 const PointerType *PT = SyncExpr->getType()->getAs<PointerType>();
2163 if (!PT || !PT->getPointeeType()->isVoidType())
2164 return StmtError(Diag(AtLoc, diag::error_objc_synchronized_expects_object)
2165 << SyncExpr->getType() << SyncExpr->getSourceRange());
2168 return Owned(new (Context) ObjCAtSynchronizedStmt(AtLoc, SyncExpr, SyncBody));
2171 /// ActOnCXXCatchBlock - Takes an exception declaration and a handler block
2172 /// and creates a proper catch handler from them.
2174 Sema::ActOnCXXCatchBlock(SourceLocation CatchLoc, Decl *ExDecl,
2175 Stmt *HandlerBlock) {
2176 // There's nothing to test that ActOnExceptionDecl didn't already test.
2177 return Owned(new (Context) CXXCatchStmt(CatchLoc,
2178 cast_or_null<VarDecl>(ExDecl),
2184 class TypeWithHandler {
2188 TypeWithHandler(const QualType &type, CXXCatchStmt *statement)
2189 : t(type), stmt(statement) {}
2191 // An arbitrary order is fine as long as it places identical
2192 // types next to each other.
2193 bool operator<(const TypeWithHandler &y) const {
2194 if (t.getAsOpaquePtr() < y.t.getAsOpaquePtr())
2196 if (t.getAsOpaquePtr() > y.t.getAsOpaquePtr())
2199 return getTypeSpecStartLoc() < y.getTypeSpecStartLoc();
2202 bool operator==(const TypeWithHandler& other) const {
2203 return t == other.t;
2206 CXXCatchStmt *getCatchStmt() const { return stmt; }
2207 SourceLocation getTypeSpecStartLoc() const {
2208 return stmt->getExceptionDecl()->getTypeSpecStartLoc();
2214 /// ActOnCXXTryBlock - Takes a try compound-statement and a number of
2215 /// handlers and creates a try statement from them.
2217 Sema::ActOnCXXTryBlock(SourceLocation TryLoc, Stmt *TryBlock,
2218 MultiStmtArg RawHandlers) {
2219 // Don't report an error if 'try' is used in system headers.
2220 if (!getLangOptions().CXXExceptions &&
2221 !getSourceManager().isInSystemHeader(TryLoc))
2222 Diag(TryLoc, diag::err_exceptions_disabled) << "try";
2224 unsigned NumHandlers = RawHandlers.size();
2225 assert(NumHandlers > 0 &&
2226 "The parser shouldn't call this if there are no handlers.");
2227 Stmt **Handlers = RawHandlers.get();
2229 llvm::SmallVector<TypeWithHandler, 8> TypesWithHandlers;
2231 for (unsigned i = 0; i < NumHandlers; ++i) {
2232 CXXCatchStmt *Handler = llvm::cast<CXXCatchStmt>(Handlers[i]);
2233 if (!Handler->getExceptionDecl()) {
2234 if (i < NumHandlers - 1)
2235 return StmtError(Diag(Handler->getLocStart(),
2236 diag::err_early_catch_all));
2241 const QualType CaughtType = Handler->getCaughtType();
2242 const QualType CanonicalCaughtType = Context.getCanonicalType(CaughtType);
2243 TypesWithHandlers.push_back(TypeWithHandler(CanonicalCaughtType, Handler));
2246 // Detect handlers for the same type as an earlier one.
2247 if (NumHandlers > 1) {
2248 llvm::array_pod_sort(TypesWithHandlers.begin(), TypesWithHandlers.end());
2250 TypeWithHandler prev = TypesWithHandlers[0];
2251 for (unsigned i = 1; i < TypesWithHandlers.size(); ++i) {
2252 TypeWithHandler curr = TypesWithHandlers[i];
2255 Diag(curr.getTypeSpecStartLoc(),
2256 diag::warn_exception_caught_by_earlier_handler)
2257 << curr.getCatchStmt()->getCaughtType().getAsString();
2258 Diag(prev.getTypeSpecStartLoc(),
2259 diag::note_previous_exception_handler)
2260 << prev.getCatchStmt()->getCaughtType().getAsString();
2267 getCurFunction()->setHasBranchProtectedScope();
2269 // FIXME: We should detect handlers that cannot catch anything because an
2270 // earlier handler catches a superclass. Need to find a method that is not
2271 // quadratic for this.
2272 // Neither of these are explicitly forbidden, but every compiler detects them
2275 return Owned(CXXTryStmt::Create(Context, TryLoc, TryBlock,
2276 Handlers, NumHandlers));
2280 Sema::ActOnSEHTryBlock(bool IsCXXTry,
2281 SourceLocation TryLoc,
2284 assert(TryBlock && Handler);
2286 getCurFunction()->setHasBranchProtectedScope();
2288 return Owned(SEHTryStmt::Create(Context,IsCXXTry,TryLoc,TryBlock,Handler));
2292 Sema::ActOnSEHExceptBlock(SourceLocation Loc,
2295 assert(FilterExpr && Block);
2297 if(!FilterExpr->getType()->isIntegerType()) {
2298 return StmtError(Diag(FilterExpr->getExprLoc(),
2299 diag::err_filter_expression_integral)
2300 << FilterExpr->getType());
2303 return Owned(SEHExceptStmt::Create(Context,Loc,FilterExpr,Block));
2307 Sema::ActOnSEHFinallyBlock(SourceLocation Loc,
2310 return Owned(SEHFinallyStmt::Create(Context,Loc,Block));