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      1 //===--- RewriteObjC.cpp - Playground for the code rewriter ---------------===//
      2 //
      3 //                     The LLVM Compiler Infrastructure
      4 //
      5 // This file is distributed under the University of Illinois Open Source
      6 // License. See LICENSE.TXT for details.
      7 //
      8 //===----------------------------------------------------------------------===//
      9 //
     10 // Hacks and fun related to the code rewriter.
     11 //
     12 //===----------------------------------------------------------------------===//
     13 
     14 #include "clang/Rewrite/Frontend/ASTConsumers.h"
     15 #include "clang/AST/AST.h"
     16 #include "clang/AST/ASTConsumer.h"
     17 #include "clang/AST/Attr.h"
     18 #include "clang/AST/ParentMap.h"
     19 #include "clang/Basic/CharInfo.h"
     20 #include "clang/Basic/Diagnostic.h"
     21 #include "clang/Basic/IdentifierTable.h"
     22 #include "clang/Basic/SourceManager.h"
     23 #include "clang/Lex/Lexer.h"
     24 #include "clang/Rewrite/Core/Rewriter.h"
     25 #include "llvm/ADT/DenseSet.h"
     26 #include "llvm/ADT/OwningPtr.h"
     27 #include "llvm/ADT/SmallPtrSet.h"
     28 #include "llvm/ADT/StringExtras.h"
     29 #include "llvm/Support/MemoryBuffer.h"
     30 #include "llvm/Support/raw_ostream.h"
     31 
     32 using namespace clang;
     33 using llvm::utostr;
     34 
     35 namespace {
     36   class RewriteObjC : public ASTConsumer {
     37   protected:
     38 
     39     enum {
     40       BLOCK_FIELD_IS_OBJECT   =  3,  /* id, NSObject, __attribute__((NSObject)),
     41                                         block, ... */
     42       BLOCK_FIELD_IS_BLOCK    =  7,  /* a block variable */
     43       BLOCK_FIELD_IS_BYREF    =  8,  /* the on stack structure holding the
     44                                         __block variable */
     45       BLOCK_FIELD_IS_WEAK     = 16,  /* declared __weak, only used in byref copy
     46                                         helpers */
     47       BLOCK_BYREF_CALLER      = 128, /* called from __block (byref) copy/dispose
     48                                         support routines */
     49       BLOCK_BYREF_CURRENT_MAX = 256
     50     };
     51 
     52     enum {
     53       BLOCK_NEEDS_FREE =        (1 << 24),
     54       BLOCK_HAS_COPY_DISPOSE =  (1 << 25),
     55       BLOCK_HAS_CXX_OBJ =       (1 << 26),
     56       BLOCK_IS_GC =             (1 << 27),
     57       BLOCK_IS_GLOBAL =         (1 << 28),
     58       BLOCK_HAS_DESCRIPTOR =    (1 << 29)
     59     };
     60     static const int OBJC_ABI_VERSION = 7;
     61 
     62     Rewriter Rewrite;
     63     DiagnosticsEngine &Diags;
     64     const LangOptions &LangOpts;
     65     ASTContext *Context;
     66     SourceManager *SM;
     67     TranslationUnitDecl *TUDecl;
     68     FileID MainFileID;
     69     const char *MainFileStart, *MainFileEnd;
     70     Stmt *CurrentBody;
     71     ParentMap *PropParentMap; // created lazily.
     72     std::string InFileName;
     73     raw_ostream* OutFile;
     74     std::string Preamble;
     75 
     76     TypeDecl *ProtocolTypeDecl;
     77     VarDecl *GlobalVarDecl;
     78     unsigned RewriteFailedDiag;
     79     // ObjC string constant support.
     80     unsigned NumObjCStringLiterals;
     81     VarDecl *ConstantStringClassReference;
     82     RecordDecl *NSStringRecord;
     83 
     84     // ObjC foreach break/continue generation support.
     85     int BcLabelCount;
     86 
     87     unsigned TryFinallyContainsReturnDiag;
     88     // Needed for super.
     89     ObjCMethodDecl *CurMethodDef;
     90     RecordDecl *SuperStructDecl;
     91     RecordDecl *ConstantStringDecl;
     92 
     93     FunctionDecl *MsgSendFunctionDecl;
     94     FunctionDecl *MsgSendSuperFunctionDecl;
     95     FunctionDecl *MsgSendStretFunctionDecl;
     96     FunctionDecl *MsgSendSuperStretFunctionDecl;
     97     FunctionDecl *MsgSendFpretFunctionDecl;
     98     FunctionDecl *GetClassFunctionDecl;
     99     FunctionDecl *GetMetaClassFunctionDecl;
    100     FunctionDecl *GetSuperClassFunctionDecl;
    101     FunctionDecl *SelGetUidFunctionDecl;
    102     FunctionDecl *CFStringFunctionDecl;
    103     FunctionDecl *SuperContructorFunctionDecl;
    104     FunctionDecl *CurFunctionDef;
    105     FunctionDecl *CurFunctionDeclToDeclareForBlock;
    106 
    107     /* Misc. containers needed for meta-data rewrite. */
    108     SmallVector<ObjCImplementationDecl *, 8> ClassImplementation;
    109     SmallVector<ObjCCategoryImplDecl *, 8> CategoryImplementation;
    110     llvm::SmallPtrSet<ObjCInterfaceDecl*, 8> ObjCSynthesizedStructs;
    111     llvm::SmallPtrSet<ObjCProtocolDecl*, 8> ObjCSynthesizedProtocols;
    112     llvm::SmallPtrSet<ObjCInterfaceDecl*, 8> ObjCForwardDecls;
    113     llvm::DenseMap<ObjCMethodDecl*, std::string> MethodInternalNames;
    114     SmallVector<Stmt *, 32> Stmts;
    115     SmallVector<int, 8> ObjCBcLabelNo;
    116     // Remember all the @protocol(<expr>) expressions.
    117     llvm::SmallPtrSet<ObjCProtocolDecl *, 32> ProtocolExprDecls;
    118 
    119     llvm::DenseSet<uint64_t> CopyDestroyCache;
    120 
    121     // Block expressions.
    122     SmallVector<BlockExpr *, 32> Blocks;
    123     SmallVector<int, 32> InnerDeclRefsCount;
    124     SmallVector<DeclRefExpr *, 32> InnerDeclRefs;
    125 
    126     SmallVector<DeclRefExpr *, 32> BlockDeclRefs;
    127 
    128     // Block related declarations.
    129     SmallVector<ValueDecl *, 8> BlockByCopyDecls;
    130     llvm::SmallPtrSet<ValueDecl *, 8> BlockByCopyDeclsPtrSet;
    131     SmallVector<ValueDecl *, 8> BlockByRefDecls;
    132     llvm::SmallPtrSet<ValueDecl *, 8> BlockByRefDeclsPtrSet;
    133     llvm::DenseMap<ValueDecl *, unsigned> BlockByRefDeclNo;
    134     llvm::SmallPtrSet<ValueDecl *, 8> ImportedBlockDecls;
    135     llvm::SmallPtrSet<VarDecl *, 8> ImportedLocalExternalDecls;
    136 
    137     llvm::DenseMap<BlockExpr *, std::string> RewrittenBlockExprs;
    138 
    139     // This maps an original source AST to it's rewritten form. This allows
    140     // us to avoid rewriting the same node twice (which is very uncommon).
    141     // This is needed to support some of the exotic property rewriting.
    142     llvm::DenseMap<Stmt *, Stmt *> ReplacedNodes;
    143 
    144     // Needed for header files being rewritten
    145     bool IsHeader;
    146     bool SilenceRewriteMacroWarning;
    147     bool objc_impl_method;
    148 
    149     bool DisableReplaceStmt;
    150     class DisableReplaceStmtScope {
    151       RewriteObjC &R;
    152       bool SavedValue;
    153 
    154     public:
    155       DisableReplaceStmtScope(RewriteObjC &R)
    156         : R(R), SavedValue(R.DisableReplaceStmt) {
    157         R.DisableReplaceStmt = true;
    158       }
    159       ~DisableReplaceStmtScope() {
    160         R.DisableReplaceStmt = SavedValue;
    161       }
    162     };
    163     void InitializeCommon(ASTContext &context);
    164 
    165   public:
    166 
    167     // Top Level Driver code.
    168     virtual bool HandleTopLevelDecl(DeclGroupRef D) {
    169       for (DeclGroupRef::iterator I = D.begin(), E = D.end(); I != E; ++I) {
    170         if (ObjCInterfaceDecl *Class = dyn_cast<ObjCInterfaceDecl>(*I)) {
    171           if (!Class->isThisDeclarationADefinition()) {
    172             RewriteForwardClassDecl(D);
    173             break;
    174           }
    175         }
    176 
    177         if (ObjCProtocolDecl *Proto = dyn_cast<ObjCProtocolDecl>(*I)) {
    178           if (!Proto->isThisDeclarationADefinition()) {
    179             RewriteForwardProtocolDecl(D);
    180             break;
    181           }
    182         }
    183 
    184         HandleTopLevelSingleDecl(*I);
    185       }
    186       return true;
    187     }
    188     void HandleTopLevelSingleDecl(Decl *D);
    189     void HandleDeclInMainFile(Decl *D);
    190     RewriteObjC(std::string inFile, raw_ostream *OS,
    191                 DiagnosticsEngine &D, const LangOptions &LOpts,
    192                 bool silenceMacroWarn);
    193 
    194     ~RewriteObjC() {}
    195 
    196     virtual void HandleTranslationUnit(ASTContext &C);
    197 
    198     void ReplaceStmt(Stmt *Old, Stmt *New) {
    199       Stmt *ReplacingStmt = ReplacedNodes[Old];
    200 
    201       if (ReplacingStmt)
    202         return; // We can't rewrite the same node twice.
    203 
    204       if (DisableReplaceStmt)
    205         return;
    206 
    207       // If replacement succeeded or warning disabled return with no warning.
    208       if (!Rewrite.ReplaceStmt(Old, New)) {
    209         ReplacedNodes[Old] = New;
    210         return;
    211       }
    212       if (SilenceRewriteMacroWarning)
    213         return;
    214       Diags.Report(Context->getFullLoc(Old->getLocStart()), RewriteFailedDiag)
    215                    << Old->getSourceRange();
    216     }
    217 
    218     void ReplaceStmtWithRange(Stmt *Old, Stmt *New, SourceRange SrcRange) {
    219       if (DisableReplaceStmt)
    220         return;
    221 
    222       // Measure the old text.
    223       int Size = Rewrite.getRangeSize(SrcRange);
    224       if (Size == -1) {
    225         Diags.Report(Context->getFullLoc(Old->getLocStart()), RewriteFailedDiag)
    226                      << Old->getSourceRange();
    227         return;
    228       }
    229       // Get the new text.
    230       std::string SStr;
    231       llvm::raw_string_ostream S(SStr);
    232       New->printPretty(S, 0, PrintingPolicy(LangOpts));
    233       const std::string &Str = S.str();
    234 
    235       // If replacement succeeded or warning disabled return with no warning.
    236       if (!Rewrite.ReplaceText(SrcRange.getBegin(), Size, Str)) {
    237         ReplacedNodes[Old] = New;
    238         return;
    239       }
    240       if (SilenceRewriteMacroWarning)
    241         return;
    242       Diags.Report(Context->getFullLoc(Old->getLocStart()), RewriteFailedDiag)
    243                    << Old->getSourceRange();
    244     }
    245 
    246     void InsertText(SourceLocation Loc, StringRef Str,
    247                     bool InsertAfter = true) {
    248       // If insertion succeeded or warning disabled return with no warning.
    249       if (!Rewrite.InsertText(Loc, Str, InsertAfter) ||
    250           SilenceRewriteMacroWarning)
    251         return;
    252 
    253       Diags.Report(Context->getFullLoc(Loc), RewriteFailedDiag);
    254     }
    255 
    256     void ReplaceText(SourceLocation Start, unsigned OrigLength,
    257                      StringRef Str) {
    258       // If removal succeeded or warning disabled return with no warning.
    259       if (!Rewrite.ReplaceText(Start, OrigLength, Str) ||
    260           SilenceRewriteMacroWarning)
    261         return;
    262 
    263       Diags.Report(Context->getFullLoc(Start), RewriteFailedDiag);
    264     }
    265 
    266     // Syntactic Rewriting.
    267     void RewriteRecordBody(RecordDecl *RD);
    268     void RewriteInclude();
    269     void RewriteForwardClassDecl(DeclGroupRef D);
    270     void RewriteForwardClassDecl(const SmallVectorImpl<Decl *> &DG);
    271     void RewriteForwardClassEpilogue(ObjCInterfaceDecl *ClassDecl,
    272                                      const std::string &typedefString);
    273     void RewriteImplementations();
    274     void RewritePropertyImplDecl(ObjCPropertyImplDecl *PID,
    275                                  ObjCImplementationDecl *IMD,
    276                                  ObjCCategoryImplDecl *CID);
    277     void RewriteInterfaceDecl(ObjCInterfaceDecl *Dcl);
    278     void RewriteImplementationDecl(Decl *Dcl);
    279     void RewriteObjCMethodDecl(const ObjCInterfaceDecl *IDecl,
    280                                ObjCMethodDecl *MDecl, std::string &ResultStr);
    281     void RewriteTypeIntoString(QualType T, std::string &ResultStr,
    282                                const FunctionType *&FPRetType);
    283     void RewriteByRefString(std::string &ResultStr, const std::string &Name,
    284                             ValueDecl *VD, bool def=false);
    285     void RewriteCategoryDecl(ObjCCategoryDecl *Dcl);
    286     void RewriteProtocolDecl(ObjCProtocolDecl *Dcl);
    287     void RewriteForwardProtocolDecl(DeclGroupRef D);
    288     void RewriteForwardProtocolDecl(const SmallVectorImpl<Decl *> &DG);
    289     void RewriteMethodDeclaration(ObjCMethodDecl *Method);
    290     void RewriteProperty(ObjCPropertyDecl *prop);
    291     void RewriteFunctionDecl(FunctionDecl *FD);
    292     void RewriteBlockPointerType(std::string& Str, QualType Type);
    293     void RewriteBlockPointerTypeVariable(std::string& Str, ValueDecl *VD);
    294     void RewriteBlockLiteralFunctionDecl(FunctionDecl *FD);
    295     void RewriteObjCQualifiedInterfaceTypes(Decl *Dcl);
    296     void RewriteTypeOfDecl(VarDecl *VD);
    297     void RewriteObjCQualifiedInterfaceTypes(Expr *E);
    298 
    299     // Expression Rewriting.
    300     Stmt *RewriteFunctionBodyOrGlobalInitializer(Stmt *S);
    301     Stmt *RewriteAtEncode(ObjCEncodeExpr *Exp);
    302     Stmt *RewritePropertyOrImplicitGetter(PseudoObjectExpr *Pseudo);
    303     Stmt *RewritePropertyOrImplicitSetter(PseudoObjectExpr *Pseudo);
    304     Stmt *RewriteAtSelector(ObjCSelectorExpr *Exp);
    305     Stmt *RewriteMessageExpr(ObjCMessageExpr *Exp);
    306     Stmt *RewriteObjCStringLiteral(ObjCStringLiteral *Exp);
    307     Stmt *RewriteObjCProtocolExpr(ObjCProtocolExpr *Exp);
    308     void RewriteTryReturnStmts(Stmt *S);
    309     void RewriteSyncReturnStmts(Stmt *S, std::string buf);
    310     Stmt *RewriteObjCTryStmt(ObjCAtTryStmt *S);
    311     Stmt *RewriteObjCSynchronizedStmt(ObjCAtSynchronizedStmt *S);
    312     Stmt *RewriteObjCThrowStmt(ObjCAtThrowStmt *S);
    313     Stmt *RewriteObjCForCollectionStmt(ObjCForCollectionStmt *S,
    314                                        SourceLocation OrigEnd);
    315     Stmt *RewriteBreakStmt(BreakStmt *S);
    316     Stmt *RewriteContinueStmt(ContinueStmt *S);
    317     void RewriteCastExpr(CStyleCastExpr *CE);
    318 
    319     // Block rewriting.
    320     void RewriteBlocksInFunctionProtoType(QualType funcType, NamedDecl *D);
    321 
    322     // Block specific rewrite rules.
    323     void RewriteBlockPointerDecl(NamedDecl *VD);
    324     void RewriteByRefVar(VarDecl *VD);
    325     Stmt *RewriteBlockDeclRefExpr(DeclRefExpr *VD);
    326     Stmt *RewriteLocalVariableExternalStorage(DeclRefExpr *DRE);
    327     void RewriteBlockPointerFunctionArgs(FunctionDecl *FD);
    328 
    329     void RewriteObjCInternalStruct(ObjCInterfaceDecl *CDecl,
    330                                       std::string &Result);
    331 
    332     virtual void Initialize(ASTContext &context) = 0;
    333 
    334     // Metadata Rewriting.
    335     virtual void RewriteMetaDataIntoBuffer(std::string &Result) = 0;
    336     virtual void RewriteObjCProtocolListMetaData(const ObjCList<ObjCProtocolDecl> &Prots,
    337                                                  StringRef prefix,
    338                                                  StringRef ClassName,
    339                                                  std::string &Result) = 0;
    340     virtual void RewriteObjCCategoryImplDecl(ObjCCategoryImplDecl *CDecl,
    341                                              std::string &Result) = 0;
    342     virtual void RewriteObjCProtocolMetaData(ObjCProtocolDecl *Protocol,
    343                                      StringRef prefix,
    344                                      StringRef ClassName,
    345                                      std::string &Result) = 0;
    346     virtual void RewriteObjCClassMetaData(ObjCImplementationDecl *IDecl,
    347                                           std::string &Result) = 0;
    348 
    349     // Rewriting ivar access
    350     virtual Stmt *RewriteObjCIvarRefExpr(ObjCIvarRefExpr *IV) = 0;
    351     virtual void RewriteIvarOffsetComputation(ObjCIvarDecl *ivar,
    352                                          std::string &Result) = 0;
    353 
    354     // Misc. AST transformation routines. Sometimes they end up calling
    355     // rewriting routines on the new ASTs.
    356     CallExpr *SynthesizeCallToFunctionDecl(FunctionDecl *FD,
    357                                            Expr **args, unsigned nargs,
    358                                            SourceLocation StartLoc=SourceLocation(),
    359                                            SourceLocation EndLoc=SourceLocation());
    360     CallExpr *SynthMsgSendStretCallExpr(FunctionDecl *MsgSendStretFlavor,
    361                                         QualType msgSendType,
    362                                         QualType returnType,
    363                                         SmallVectorImpl<QualType> &ArgTypes,
    364                                         SmallVectorImpl<Expr*> &MsgExprs,
    365                                         ObjCMethodDecl *Method);
    366     Stmt *SynthMessageExpr(ObjCMessageExpr *Exp,
    367                            SourceLocation StartLoc=SourceLocation(),
    368                            SourceLocation EndLoc=SourceLocation());
    369 
    370     void SynthCountByEnumWithState(std::string &buf);
    371     void SynthMsgSendFunctionDecl();
    372     void SynthMsgSendSuperFunctionDecl();
    373     void SynthMsgSendStretFunctionDecl();
    374     void SynthMsgSendFpretFunctionDecl();
    375     void SynthMsgSendSuperStretFunctionDecl();
    376     void SynthGetClassFunctionDecl();
    377     void SynthGetMetaClassFunctionDecl();
    378     void SynthGetSuperClassFunctionDecl();
    379     void SynthSelGetUidFunctionDecl();
    380     void SynthSuperContructorFunctionDecl();
    381 
    382     std::string SynthesizeByrefCopyDestroyHelper(VarDecl *VD, int flag);
    383     std::string SynthesizeBlockHelperFuncs(BlockExpr *CE, int i,
    384                                       StringRef funcName, std::string Tag);
    385     std::string SynthesizeBlockFunc(BlockExpr *CE, int i,
    386                                       StringRef funcName, std::string Tag);
    387     std::string SynthesizeBlockImpl(BlockExpr *CE,
    388                                     std::string Tag, std::string Desc);
    389     std::string SynthesizeBlockDescriptor(std::string DescTag,
    390                                           std::string ImplTag,
    391                                           int i, StringRef funcName,
    392                                           unsigned hasCopy);
    393     Stmt *SynthesizeBlockCall(CallExpr *Exp, const Expr* BlockExp);
    394     void SynthesizeBlockLiterals(SourceLocation FunLocStart,
    395                                  StringRef FunName);
    396     FunctionDecl *SynthBlockInitFunctionDecl(StringRef name);
    397     Stmt *SynthBlockInitExpr(BlockExpr *Exp,
    398             const SmallVectorImpl<DeclRefExpr *> &InnerBlockDeclRefs);
    399 
    400     // Misc. helper routines.
    401     QualType getProtocolType();
    402     void WarnAboutReturnGotoStmts(Stmt *S);
    403     void HasReturnStmts(Stmt *S, bool &hasReturns);
    404     void CheckFunctionPointerDecl(QualType dType, NamedDecl *ND);
    405     void InsertBlockLiteralsWithinFunction(FunctionDecl *FD);
    406     void InsertBlockLiteralsWithinMethod(ObjCMethodDecl *MD);
    407 
    408     bool IsDeclStmtInForeachHeader(DeclStmt *DS);
    409     void CollectBlockDeclRefInfo(BlockExpr *Exp);
    410     void GetBlockDeclRefExprs(Stmt *S);
    411     void GetInnerBlockDeclRefExprs(Stmt *S,
    412                 SmallVectorImpl<DeclRefExpr *> &InnerBlockDeclRefs,
    413                 llvm::SmallPtrSet<const DeclContext *, 8> &InnerContexts);
    414 
    415     // We avoid calling Type::isBlockPointerType(), since it operates on the
    416     // canonical type. We only care if the top-level type is a closure pointer.
    417     bool isTopLevelBlockPointerType(QualType T) {
    418       return isa<BlockPointerType>(T);
    419     }
    420 
    421     /// convertBlockPointerToFunctionPointer - Converts a block-pointer type
    422     /// to a function pointer type and upon success, returns true; false
    423     /// otherwise.
    424     bool convertBlockPointerToFunctionPointer(QualType &T) {
    425       if (isTopLevelBlockPointerType(T)) {
    426         const BlockPointerType *BPT = T->getAs<BlockPointerType>();
    427         T = Context->getPointerType(BPT->getPointeeType());
    428         return true;
    429       }
    430       return false;
    431     }
    432 
    433     bool needToScanForQualifiers(QualType T);
    434     QualType getSuperStructType();
    435     QualType getConstantStringStructType();
    436     QualType convertFunctionTypeOfBlocks(const FunctionType *FT);
    437     bool BufferContainsPPDirectives(const char *startBuf, const char *endBuf);
    438 
    439     void convertToUnqualifiedObjCType(QualType &T) {
    440       if (T->isObjCQualifiedIdType())
    441         T = Context->getObjCIdType();
    442       else if (T->isObjCQualifiedClassType())
    443         T = Context->getObjCClassType();
    444       else if (T->isObjCObjectPointerType() &&
    445                T->getPointeeType()->isObjCQualifiedInterfaceType()) {
    446         if (const ObjCObjectPointerType * OBJPT =
    447               T->getAsObjCInterfacePointerType()) {
    448           const ObjCInterfaceType *IFaceT = OBJPT->getInterfaceType();
    449           T = QualType(IFaceT, 0);
    450           T = Context->getPointerType(T);
    451         }
    452      }
    453     }
    454 
    455     // FIXME: This predicate seems like it would be useful to add to ASTContext.
    456     bool isObjCType(QualType T) {
    457       if (!LangOpts.ObjC1 && !LangOpts.ObjC2)
    458         return false;
    459 
    460       QualType OCT = Context->getCanonicalType(T).getUnqualifiedType();
    461 
    462       if (OCT == Context->getCanonicalType(Context->getObjCIdType()) ||
    463           OCT == Context->getCanonicalType(Context->getObjCClassType()))
    464         return true;
    465 
    466       if (const PointerType *PT = OCT->getAs<PointerType>()) {
    467         if (isa<ObjCInterfaceType>(PT->getPointeeType()) ||
    468             PT->getPointeeType()->isObjCQualifiedIdType())
    469           return true;
    470       }
    471       return false;
    472     }
    473     bool PointerTypeTakesAnyBlockArguments(QualType QT);
    474     bool PointerTypeTakesAnyObjCQualifiedType(QualType QT);
    475     void GetExtentOfArgList(const char *Name, const char *&LParen,
    476                             const char *&RParen);
    477 
    478     void QuoteDoublequotes(std::string &From, std::string &To) {
    479       for (unsigned i = 0; i < From.length(); i++) {
    480         if (From[i] == '"')
    481           To += "\\\"";
    482         else
    483           To += From[i];
    484       }
    485     }
    486 
    487     QualType getSimpleFunctionType(QualType result,
    488                                    ArrayRef<QualType> args,
    489                                    bool variadic = false) {
    490       if (result == Context->getObjCInstanceType())
    491         result =  Context->getObjCIdType();
    492       FunctionProtoType::ExtProtoInfo fpi;
    493       fpi.Variadic = variadic;
    494       return Context->getFunctionType(result, args, fpi);
    495     }
    496 
    497     // Helper function: create a CStyleCastExpr with trivial type source info.
    498     CStyleCastExpr* NoTypeInfoCStyleCastExpr(ASTContext *Ctx, QualType Ty,
    499                                              CastKind Kind, Expr *E) {
    500       TypeSourceInfo *TInfo = Ctx->getTrivialTypeSourceInfo(Ty, SourceLocation());
    501       return CStyleCastExpr::Create(*Ctx, Ty, VK_RValue, Kind, E, 0, TInfo,
    502                                     SourceLocation(), SourceLocation());
    503     }
    504   };
    505 
    506   class RewriteObjCFragileABI : public RewriteObjC {
    507   public:
    508 
    509     RewriteObjCFragileABI(std::string inFile, raw_ostream *OS,
    510                 DiagnosticsEngine &D, const LangOptions &LOpts,
    511                 bool silenceMacroWarn) : RewriteObjC(inFile, OS,
    512                                                      D, LOpts,
    513                                                      silenceMacroWarn) {}
    514 
    515     ~RewriteObjCFragileABI() {}
    516     virtual void Initialize(ASTContext &context);
    517 
    518     // Rewriting metadata
    519     template<typename MethodIterator>
    520     void RewriteObjCMethodsMetaData(MethodIterator MethodBegin,
    521                                     MethodIterator MethodEnd,
    522                                     bool IsInstanceMethod,
    523                                     StringRef prefix,
    524                                     StringRef ClassName,
    525                                     std::string &Result);
    526     virtual void RewriteObjCProtocolMetaData(ObjCProtocolDecl *Protocol,
    527                                              StringRef prefix,
    528                                              StringRef ClassName,
    529                                              std::string &Result);
    530     virtual void RewriteObjCProtocolListMetaData(
    531                   const ObjCList<ObjCProtocolDecl> &Prots,
    532                   StringRef prefix, StringRef ClassName, std::string &Result);
    533     virtual void RewriteObjCClassMetaData(ObjCImplementationDecl *IDecl,
    534                                           std::string &Result);
    535     virtual void RewriteMetaDataIntoBuffer(std::string &Result);
    536     virtual void RewriteObjCCategoryImplDecl(ObjCCategoryImplDecl *CDecl,
    537                                              std::string &Result);
    538 
    539     // Rewriting ivar
    540     virtual void RewriteIvarOffsetComputation(ObjCIvarDecl *ivar,
    541                                               std::string &Result);
    542     virtual Stmt *RewriteObjCIvarRefExpr(ObjCIvarRefExpr *IV);
    543   };
    544 }
    545 
    546 void RewriteObjC::RewriteBlocksInFunctionProtoType(QualType funcType,
    547                                                    NamedDecl *D) {
    548   if (const FunctionProtoType *fproto
    549       = dyn_cast<FunctionProtoType>(funcType.IgnoreParens())) {
    550     for (FunctionProtoType::arg_type_iterator I = fproto->arg_type_begin(),
    551          E = fproto->arg_type_end(); I && (I != E); ++I)
    552       if (isTopLevelBlockPointerType(*I)) {
    553         // All the args are checked/rewritten. Don't call twice!
    554         RewriteBlockPointerDecl(D);
    555         break;
    556       }
    557   }
    558 }
    559 
    560 void RewriteObjC::CheckFunctionPointerDecl(QualType funcType, NamedDecl *ND) {
    561   const PointerType *PT = funcType->getAs<PointerType>();
    562   if (PT && PointerTypeTakesAnyBlockArguments(funcType))
    563     RewriteBlocksInFunctionProtoType(PT->getPointeeType(), ND);
    564 }
    565 
    566 static bool IsHeaderFile(const std::string &Filename) {
    567   std::string::size_type DotPos = Filename.rfind('.');
    568 
    569   if (DotPos == std::string::npos) {
    570     // no file extension
    571     return false;
    572   }
    573 
    574   std::string Ext = std::string(Filename.begin()+DotPos+1, Filename.end());
    575   // C header: .h
    576   // C++ header: .hh or .H;
    577   return Ext == "h" || Ext == "hh" || Ext == "H";
    578 }
    579 
    580 RewriteObjC::RewriteObjC(std::string inFile, raw_ostream* OS,
    581                          DiagnosticsEngine &D, const LangOptions &LOpts,
    582                          bool silenceMacroWarn)
    583       : Diags(D), LangOpts(LOpts), InFileName(inFile), OutFile(OS),
    584         SilenceRewriteMacroWarning(silenceMacroWarn) {
    585   IsHeader = IsHeaderFile(inFile);
    586   RewriteFailedDiag = Diags.getCustomDiagID(DiagnosticsEngine::Warning,
    587                "rewriting sub-expression within a macro (may not be correct)");
    588   TryFinallyContainsReturnDiag = Diags.getCustomDiagID(
    589                DiagnosticsEngine::Warning,
    590                "rewriter doesn't support user-specified control flow semantics "
    591                "for @try/@finally (code may not execute properly)");
    592 }
    593 
    594 ASTConsumer *clang::CreateObjCRewriter(const std::string& InFile,
    595                                        raw_ostream* OS,
    596                                        DiagnosticsEngine &Diags,
    597                                        const LangOptions &LOpts,
    598                                        bool SilenceRewriteMacroWarning) {
    599   return new RewriteObjCFragileABI(InFile, OS, Diags, LOpts, SilenceRewriteMacroWarning);
    600 }
    601 
    602 void RewriteObjC::InitializeCommon(ASTContext &context) {
    603   Context = &context;
    604   SM = &Context->getSourceManager();
    605   TUDecl = Context->getTranslationUnitDecl();
    606   MsgSendFunctionDecl = 0;
    607   MsgSendSuperFunctionDecl = 0;
    608   MsgSendStretFunctionDecl = 0;
    609   MsgSendSuperStretFunctionDecl = 0;
    610   MsgSendFpretFunctionDecl = 0;
    611   GetClassFunctionDecl = 0;
    612   GetMetaClassFunctionDecl = 0;
    613   GetSuperClassFunctionDecl = 0;
    614   SelGetUidFunctionDecl = 0;
    615   CFStringFunctionDecl = 0;
    616   ConstantStringClassReference = 0;
    617   NSStringRecord = 0;
    618   CurMethodDef = 0;
    619   CurFunctionDef = 0;
    620   CurFunctionDeclToDeclareForBlock = 0;
    621   GlobalVarDecl = 0;
    622   SuperStructDecl = 0;
    623   ProtocolTypeDecl = 0;
    624   ConstantStringDecl = 0;
    625   BcLabelCount = 0;
    626   SuperContructorFunctionDecl = 0;
    627   NumObjCStringLiterals = 0;
    628   PropParentMap = 0;
    629   CurrentBody = 0;
    630   DisableReplaceStmt = false;
    631   objc_impl_method = false;
    632 
    633   // Get the ID and start/end of the main file.
    634   MainFileID = SM->getMainFileID();
    635   const llvm::MemoryBuffer *MainBuf = SM->getBuffer(MainFileID);
    636   MainFileStart = MainBuf->getBufferStart();
    637   MainFileEnd = MainBuf->getBufferEnd();
    638 
    639   Rewrite.setSourceMgr(Context->getSourceManager(), Context->getLangOpts());
    640 }
    641 
    642 //===----------------------------------------------------------------------===//
    643 // Top Level Driver Code
    644 //===----------------------------------------------------------------------===//
    645 
    646 void RewriteObjC::HandleTopLevelSingleDecl(Decl *D) {
    647   if (Diags.hasErrorOccurred())
    648     return;
    649 
    650   // Two cases: either the decl could be in the main file, or it could be in a
    651   // #included file.  If the former, rewrite it now.  If the later, check to see
    652   // if we rewrote the #include/#import.
    653   SourceLocation Loc = D->getLocation();
    654   Loc = SM->getExpansionLoc(Loc);
    655 
    656   // If this is for a builtin, ignore it.
    657   if (Loc.isInvalid()) return;
    658 
    659   // Look for built-in declarations that we need to refer during the rewrite.
    660   if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
    661     RewriteFunctionDecl(FD);
    662   } else if (VarDecl *FVD = dyn_cast<VarDecl>(D)) {
    663     // declared in <Foundation/NSString.h>
    664     if (FVD->getName() == "_NSConstantStringClassReference") {
    665       ConstantStringClassReference = FVD;
    666       return;
    667     }
    668   } else if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(D)) {
    669     if (ID->isThisDeclarationADefinition())
    670       RewriteInterfaceDecl(ID);
    671   } else if (ObjCCategoryDecl *CD = dyn_cast<ObjCCategoryDecl>(D)) {
    672     RewriteCategoryDecl(CD);
    673   } else if (ObjCProtocolDecl *PD = dyn_cast<ObjCProtocolDecl>(D)) {
    674     if (PD->isThisDeclarationADefinition())
    675       RewriteProtocolDecl(PD);
    676   } else if (LinkageSpecDecl *LSD = dyn_cast<LinkageSpecDecl>(D)) {
    677     // Recurse into linkage specifications
    678     for (DeclContext::decl_iterator DI = LSD->decls_begin(),
    679                                  DIEnd = LSD->decls_end();
    680          DI != DIEnd; ) {
    681       if (ObjCInterfaceDecl *IFace = dyn_cast<ObjCInterfaceDecl>((*DI))) {
    682         if (!IFace->isThisDeclarationADefinition()) {
    683           SmallVector<Decl *, 8> DG;
    684           SourceLocation StartLoc = IFace->getLocStart();
    685           do {
    686             if (isa<ObjCInterfaceDecl>(*DI) &&
    687                 !cast<ObjCInterfaceDecl>(*DI)->isThisDeclarationADefinition() &&
    688                 StartLoc == (*DI)->getLocStart())
    689               DG.push_back(*DI);
    690             else
    691               break;
    692 
    693             ++DI;
    694           } while (DI != DIEnd);
    695           RewriteForwardClassDecl(DG);
    696           continue;
    697         }
    698       }
    699 
    700       if (ObjCProtocolDecl *Proto = dyn_cast<ObjCProtocolDecl>((*DI))) {
    701         if (!Proto->isThisDeclarationADefinition()) {
    702           SmallVector<Decl *, 8> DG;
    703           SourceLocation StartLoc = Proto->getLocStart();
    704           do {
    705             if (isa<ObjCProtocolDecl>(*DI) &&
    706                 !cast<ObjCProtocolDecl>(*DI)->isThisDeclarationADefinition() &&
    707                 StartLoc == (*DI)->getLocStart())
    708               DG.push_back(*DI);
    709             else
    710               break;
    711 
    712             ++DI;
    713           } while (DI != DIEnd);
    714           RewriteForwardProtocolDecl(DG);
    715           continue;
    716         }
    717       }
    718 
    719       HandleTopLevelSingleDecl(*DI);
    720       ++DI;
    721     }
    722   }
    723   // If we have a decl in the main file, see if we should rewrite it.
    724   if (SM->isFromMainFile(Loc))
    725     return HandleDeclInMainFile(D);
    726 }
    727 
    728 //===----------------------------------------------------------------------===//
    729 // Syntactic (non-AST) Rewriting Code
    730 //===----------------------------------------------------------------------===//
    731 
    732 void RewriteObjC::RewriteInclude() {
    733   SourceLocation LocStart = SM->getLocForStartOfFile(MainFileID);
    734   StringRef MainBuf = SM->getBufferData(MainFileID);
    735   const char *MainBufStart = MainBuf.begin();
    736   const char *MainBufEnd = MainBuf.end();
    737   size_t ImportLen = strlen("import");
    738 
    739   // Loop over the whole file, looking for includes.
    740   for (const char *BufPtr = MainBufStart; BufPtr < MainBufEnd; ++BufPtr) {
    741     if (*BufPtr == '#') {
    742       if (++BufPtr == MainBufEnd)
    743         return;
    744       while (*BufPtr == ' ' || *BufPtr == '\t')
    745         if (++BufPtr == MainBufEnd)
    746           return;
    747       if (!strncmp(BufPtr, "import", ImportLen)) {
    748         // replace import with include
    749         SourceLocation ImportLoc =
    750           LocStart.getLocWithOffset(BufPtr-MainBufStart);
    751         ReplaceText(ImportLoc, ImportLen, "include");
    752         BufPtr += ImportLen;
    753       }
    754     }
    755   }
    756 }
    757 
    758 static std::string getIvarAccessString(ObjCIvarDecl *OID) {
    759   const ObjCInterfaceDecl *ClassDecl = OID->getContainingInterface();
    760   std::string S;
    761   S = "((struct ";
    762   S += ClassDecl->getIdentifier()->getName();
    763   S += "_IMPL *)self)->";
    764   S += OID->getName();
    765   return S;
    766 }
    767 
    768 void RewriteObjC::RewritePropertyImplDecl(ObjCPropertyImplDecl *PID,
    769                                           ObjCImplementationDecl *IMD,
    770                                           ObjCCategoryImplDecl *CID) {
    771   static bool objcGetPropertyDefined = false;
    772   static bool objcSetPropertyDefined = false;
    773   SourceLocation startLoc = PID->getLocStart();
    774   InsertText(startLoc, "// ");
    775   const char *startBuf = SM->getCharacterData(startLoc);
    776   assert((*startBuf == '@') && "bogus @synthesize location");
    777   const char *semiBuf = strchr(startBuf, ';');
    778   assert((*semiBuf == ';') && "@synthesize: can't find ';'");
    779   SourceLocation onePastSemiLoc =
    780     startLoc.getLocWithOffset(semiBuf-startBuf+1);
    781 
    782   if (PID->getPropertyImplementation() == ObjCPropertyImplDecl::Dynamic)
    783     return; // FIXME: is this correct?
    784 
    785   // Generate the 'getter' function.
    786   ObjCPropertyDecl *PD = PID->getPropertyDecl();
    787   ObjCIvarDecl *OID = PID->getPropertyIvarDecl();
    788 
    789   if (!OID)
    790     return;
    791   unsigned Attributes = PD->getPropertyAttributes();
    792   if (!PD->getGetterMethodDecl()->isDefined()) {
    793     bool GenGetProperty = !(Attributes & ObjCPropertyDecl::OBJC_PR_nonatomic) &&
    794                           (Attributes & (ObjCPropertyDecl::OBJC_PR_retain |
    795                                          ObjCPropertyDecl::OBJC_PR_copy));
    796     std::string Getr;
    797     if (GenGetProperty && !objcGetPropertyDefined) {
    798       objcGetPropertyDefined = true;
    799       // FIXME. Is this attribute correct in all cases?
    800       Getr = "\nextern \"C\" __declspec(dllimport) "
    801             "id objc_getProperty(id, SEL, long, bool);\n";
    802     }
    803     RewriteObjCMethodDecl(OID->getContainingInterface(),
    804                           PD->getGetterMethodDecl(), Getr);
    805     Getr += "{ ";
    806     // Synthesize an explicit cast to gain access to the ivar.
    807     // See objc-act.c:objc_synthesize_new_getter() for details.
    808     if (GenGetProperty) {
    809       // return objc_getProperty(self, _cmd, offsetof(ClassDecl, OID), 1)
    810       Getr += "typedef ";
    811       const FunctionType *FPRetType = 0;
    812       RewriteTypeIntoString(PD->getGetterMethodDecl()->getResultType(), Getr,
    813                             FPRetType);
    814       Getr += " _TYPE";
    815       if (FPRetType) {
    816         Getr += ")"; // close the precedence "scope" for "*".
    817 
    818         // Now, emit the argument types (if any).
    819         if (const FunctionProtoType *FT = dyn_cast<FunctionProtoType>(FPRetType)){
    820           Getr += "(";
    821           for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) {
    822             if (i) Getr += ", ";
    823             std::string ParamStr = FT->getArgType(i).getAsString(
    824                                                           Context->getPrintingPolicy());
    825             Getr += ParamStr;
    826           }
    827           if (FT->isVariadic()) {
    828             if (FT->getNumArgs()) Getr += ", ";
    829             Getr += "...";
    830           }
    831           Getr += ")";
    832         } else
    833           Getr += "()";
    834       }
    835       Getr += ";\n";
    836       Getr += "return (_TYPE)";
    837       Getr += "objc_getProperty(self, _cmd, ";
    838       RewriteIvarOffsetComputation(OID, Getr);
    839       Getr += ", 1)";
    840     }
    841     else
    842       Getr += "return " + getIvarAccessString(OID);
    843     Getr += "; }";
    844     InsertText(onePastSemiLoc, Getr);
    845   }
    846 
    847   if (PD->isReadOnly() || PD->getSetterMethodDecl()->isDefined())
    848     return;
    849 
    850   // Generate the 'setter' function.
    851   std::string Setr;
    852   bool GenSetProperty = Attributes & (ObjCPropertyDecl::OBJC_PR_retain |
    853                                       ObjCPropertyDecl::OBJC_PR_copy);
    854   if (GenSetProperty && !objcSetPropertyDefined) {
    855     objcSetPropertyDefined = true;
    856     // FIXME. Is this attribute correct in all cases?
    857     Setr = "\nextern \"C\" __declspec(dllimport) "
    858     "void objc_setProperty (id, SEL, long, id, bool, bool);\n";
    859   }
    860 
    861   RewriteObjCMethodDecl(OID->getContainingInterface(),
    862                         PD->getSetterMethodDecl(), Setr);
    863   Setr += "{ ";
    864   // Synthesize an explicit cast to initialize the ivar.
    865   // See objc-act.c:objc_synthesize_new_setter() for details.
    866   if (GenSetProperty) {
    867     Setr += "objc_setProperty (self, _cmd, ";
    868     RewriteIvarOffsetComputation(OID, Setr);
    869     Setr += ", (id)";
    870     Setr += PD->getName();
    871     Setr += ", ";
    872     if (Attributes & ObjCPropertyDecl::OBJC_PR_nonatomic)
    873       Setr += "0, ";
    874     else
    875       Setr += "1, ";
    876     if (Attributes & ObjCPropertyDecl::OBJC_PR_copy)
    877       Setr += "1)";
    878     else
    879       Setr += "0)";
    880   }
    881   else {
    882     Setr += getIvarAccessString(OID) + " = ";
    883     Setr += PD->getName();
    884   }
    885   Setr += "; }";
    886   InsertText(onePastSemiLoc, Setr);
    887 }
    888 
    889 static void RewriteOneForwardClassDecl(ObjCInterfaceDecl *ForwardDecl,
    890                                        std::string &typedefString) {
    891   typedefString += "#ifndef _REWRITER_typedef_";
    892   typedefString += ForwardDecl->getNameAsString();
    893   typedefString += "\n";
    894   typedefString += "#define _REWRITER_typedef_";
    895   typedefString += ForwardDecl->getNameAsString();
    896   typedefString += "\n";
    897   typedefString += "typedef struct objc_object ";
    898   typedefString += ForwardDecl->getNameAsString();
    899   typedefString += ";\n#endif\n";
    900 }
    901 
    902 void RewriteObjC::RewriteForwardClassEpilogue(ObjCInterfaceDecl *ClassDecl,
    903                                               const std::string &typedefString) {
    904     SourceLocation startLoc = ClassDecl->getLocStart();
    905     const char *startBuf = SM->getCharacterData(startLoc);
    906     const char *semiPtr = strchr(startBuf, ';');
    907     // Replace the @class with typedefs corresponding to the classes.
    908     ReplaceText(startLoc, semiPtr-startBuf+1, typedefString);
    909 }
    910 
    911 void RewriteObjC::RewriteForwardClassDecl(DeclGroupRef D) {
    912   std::string typedefString;
    913   for (DeclGroupRef::iterator I = D.begin(), E = D.end(); I != E; ++I) {
    914     ObjCInterfaceDecl *ForwardDecl = cast<ObjCInterfaceDecl>(*I);
    915     if (I == D.begin()) {
    916       // Translate to typedef's that forward reference structs with the same name
    917       // as the class. As a convenience, we include the original declaration
    918       // as a comment.
    919       typedefString += "// @class ";
    920       typedefString += ForwardDecl->getNameAsString();
    921       typedefString += ";\n";
    922     }
    923     RewriteOneForwardClassDecl(ForwardDecl, typedefString);
    924   }
    925   DeclGroupRef::iterator I = D.begin();
    926   RewriteForwardClassEpilogue(cast<ObjCInterfaceDecl>(*I), typedefString);
    927 }
    928 
    929 void RewriteObjC::RewriteForwardClassDecl(const SmallVectorImpl<Decl *> &D) {
    930   std::string typedefString;
    931   for (unsigned i = 0; i < D.size(); i++) {
    932     ObjCInterfaceDecl *ForwardDecl = cast<ObjCInterfaceDecl>(D[i]);
    933     if (i == 0) {
    934       typedefString += "// @class ";
    935       typedefString += ForwardDecl->getNameAsString();
    936       typedefString += ";\n";
    937     }
    938     RewriteOneForwardClassDecl(ForwardDecl, typedefString);
    939   }
    940   RewriteForwardClassEpilogue(cast<ObjCInterfaceDecl>(D[0]), typedefString);
    941 }
    942 
    943 void RewriteObjC::RewriteMethodDeclaration(ObjCMethodDecl *Method) {
    944   // When method is a synthesized one, such as a getter/setter there is
    945   // nothing to rewrite.
    946   if (Method->isImplicit())
    947     return;
    948   SourceLocation LocStart = Method->getLocStart();
    949   SourceLocation LocEnd = Method->getLocEnd();
    950 
    951   if (SM->getExpansionLineNumber(LocEnd) >
    952       SM->getExpansionLineNumber(LocStart)) {
    953     InsertText(LocStart, "#if 0\n");
    954     ReplaceText(LocEnd, 1, ";\n#endif\n");
    955   } else {
    956     InsertText(LocStart, "// ");
    957   }
    958 }
    959 
    960 void RewriteObjC::RewriteProperty(ObjCPropertyDecl *prop) {
    961   SourceLocation Loc = prop->getAtLoc();
    962 
    963   ReplaceText(Loc, 0, "// ");
    964   // FIXME: handle properties that are declared across multiple lines.
    965 }
    966 
    967 void RewriteObjC::RewriteCategoryDecl(ObjCCategoryDecl *CatDecl) {
    968   SourceLocation LocStart = CatDecl->getLocStart();
    969 
    970   // FIXME: handle category headers that are declared across multiple lines.
    971   ReplaceText(LocStart, 0, "// ");
    972 
    973   for (ObjCCategoryDecl::prop_iterator I = CatDecl->prop_begin(),
    974        E = CatDecl->prop_end(); I != E; ++I)
    975     RewriteProperty(*I);
    976 
    977   for (ObjCCategoryDecl::instmeth_iterator
    978          I = CatDecl->instmeth_begin(), E = CatDecl->instmeth_end();
    979        I != E; ++I)
    980     RewriteMethodDeclaration(*I);
    981   for (ObjCCategoryDecl::classmeth_iterator
    982          I = CatDecl->classmeth_begin(), E = CatDecl->classmeth_end();
    983        I != E; ++I)
    984     RewriteMethodDeclaration(*I);
    985 
    986   // Lastly, comment out the @end.
    987   ReplaceText(CatDecl->getAtEndRange().getBegin(),
    988               strlen("@end"), "/* @end */");
    989 }
    990 
    991 void RewriteObjC::RewriteProtocolDecl(ObjCProtocolDecl *PDecl) {
    992   SourceLocation LocStart = PDecl->getLocStart();
    993   assert(PDecl->isThisDeclarationADefinition());
    994 
    995   // FIXME: handle protocol headers that are declared across multiple lines.
    996   ReplaceText(LocStart, 0, "// ");
    997 
    998   for (ObjCProtocolDecl::instmeth_iterator
    999          I = PDecl->instmeth_begin(), E = PDecl->instmeth_end();
   1000        I != E; ++I)
   1001     RewriteMethodDeclaration(*I);
   1002   for (ObjCProtocolDecl::classmeth_iterator
   1003          I = PDecl->classmeth_begin(), E = PDecl->classmeth_end();
   1004        I != E; ++I)
   1005     RewriteMethodDeclaration(*I);
   1006 
   1007   for (ObjCInterfaceDecl::prop_iterator I = PDecl->prop_begin(),
   1008        E = PDecl->prop_end(); I != E; ++I)
   1009     RewriteProperty(*I);
   1010 
   1011   // Lastly, comment out the @end.
   1012   SourceLocation LocEnd = PDecl->getAtEndRange().getBegin();
   1013   ReplaceText(LocEnd, strlen("@end"), "/* @end */");
   1014 
   1015   // Must comment out @optional/@required
   1016   const char *startBuf = SM->getCharacterData(LocStart);
   1017   const char *endBuf = SM->getCharacterData(LocEnd);
   1018   for (const char *p = startBuf; p < endBuf; p++) {
   1019     if (*p == '@' && !strncmp(p+1, "optional", strlen("optional"))) {
   1020       SourceLocation OptionalLoc = LocStart.getLocWithOffset(p-startBuf);
   1021       ReplaceText(OptionalLoc, strlen("@optional"), "/* @optional */");
   1022 
   1023     }
   1024     else if (*p == '@' && !strncmp(p+1, "required", strlen("required"))) {
   1025       SourceLocation OptionalLoc = LocStart.getLocWithOffset(p-startBuf);
   1026       ReplaceText(OptionalLoc, strlen("@required"), "/* @required */");
   1027 
   1028     }
   1029   }
   1030 }
   1031 
   1032 void RewriteObjC::RewriteForwardProtocolDecl(DeclGroupRef D) {
   1033   SourceLocation LocStart = (*D.begin())->getLocStart();
   1034   if (LocStart.isInvalid())
   1035     llvm_unreachable("Invalid SourceLocation");
   1036   // FIXME: handle forward protocol that are declared across multiple lines.
   1037   ReplaceText(LocStart, 0, "// ");
   1038 }
   1039 
   1040 void
   1041 RewriteObjC::RewriteForwardProtocolDecl(const SmallVectorImpl<Decl *> &DG) {
   1042   SourceLocation LocStart = DG[0]->getLocStart();
   1043   if (LocStart.isInvalid())
   1044     llvm_unreachable("Invalid SourceLocation");
   1045   // FIXME: handle forward protocol that are declared across multiple lines.
   1046   ReplaceText(LocStart, 0, "// ");
   1047 }
   1048 
   1049 void RewriteObjC::RewriteTypeIntoString(QualType T, std::string &ResultStr,
   1050                                         const FunctionType *&FPRetType) {
   1051   if (T->isObjCQualifiedIdType())
   1052     ResultStr += "id";
   1053   else if (T->isFunctionPointerType() ||
   1054            T->isBlockPointerType()) {
   1055     // needs special handling, since pointer-to-functions have special
   1056     // syntax (where a decaration models use).
   1057     QualType retType = T;
   1058     QualType PointeeTy;
   1059     if (const PointerType* PT = retType->getAs<PointerType>())
   1060       PointeeTy = PT->getPointeeType();
   1061     else if (const BlockPointerType *BPT = retType->getAs<BlockPointerType>())
   1062       PointeeTy = BPT->getPointeeType();
   1063     if ((FPRetType = PointeeTy->getAs<FunctionType>())) {
   1064       ResultStr += FPRetType->getResultType().getAsString(
   1065         Context->getPrintingPolicy());
   1066       ResultStr += "(*";
   1067     }
   1068   } else
   1069     ResultStr += T.getAsString(Context->getPrintingPolicy());
   1070 }
   1071 
   1072 void RewriteObjC::RewriteObjCMethodDecl(const ObjCInterfaceDecl *IDecl,
   1073                                         ObjCMethodDecl *OMD,
   1074                                         std::string &ResultStr) {
   1075   //fprintf(stderr,"In RewriteObjCMethodDecl\n");
   1076   const FunctionType *FPRetType = 0;
   1077   ResultStr += "\nstatic ";
   1078   RewriteTypeIntoString(OMD->getResultType(), ResultStr, FPRetType);
   1079   ResultStr += " ";
   1080 
   1081   // Unique method name
   1082   std::string NameStr;
   1083 
   1084   if (OMD->isInstanceMethod())
   1085     NameStr += "_I_";
   1086   else
   1087     NameStr += "_C_";
   1088 
   1089   NameStr += IDecl->getNameAsString();
   1090   NameStr += "_";
   1091 
   1092   if (ObjCCategoryImplDecl *CID =
   1093       dyn_cast<ObjCCategoryImplDecl>(OMD->getDeclContext())) {
   1094     NameStr += CID->getNameAsString();
   1095     NameStr += "_";
   1096   }
   1097   // Append selector names, replacing ':' with '_'
   1098   {
   1099     std::string selString = OMD->getSelector().getAsString();
   1100     int len = selString.size();
   1101     for (int i = 0; i < len; i++)
   1102       if (selString[i] == ':')
   1103         selString[i] = '_';
   1104     NameStr += selString;
   1105   }
   1106   // Remember this name for metadata emission
   1107   MethodInternalNames[OMD] = NameStr;
   1108   ResultStr += NameStr;
   1109 
   1110   // Rewrite arguments
   1111   ResultStr += "(";
   1112 
   1113   // invisible arguments
   1114   if (OMD->isInstanceMethod()) {
   1115     QualType selfTy = Context->getObjCInterfaceType(IDecl);
   1116     selfTy = Context->getPointerType(selfTy);
   1117     if (!LangOpts.MicrosoftExt) {
   1118       if (ObjCSynthesizedStructs.count(const_cast<ObjCInterfaceDecl*>(IDecl)))
   1119         ResultStr += "struct ";
   1120     }
   1121     // When rewriting for Microsoft, explicitly omit the structure name.
   1122     ResultStr += IDecl->getNameAsString();
   1123     ResultStr += " *";
   1124   }
   1125   else
   1126     ResultStr += Context->getObjCClassType().getAsString(
   1127       Context->getPrintingPolicy());
   1128 
   1129   ResultStr += " self, ";
   1130   ResultStr += Context->getObjCSelType().getAsString(Context->getPrintingPolicy());
   1131   ResultStr += " _cmd";
   1132 
   1133   // Method arguments.
   1134   for (ObjCMethodDecl::param_iterator PI = OMD->param_begin(),
   1135        E = OMD->param_end(); PI != E; ++PI) {
   1136     ParmVarDecl *PDecl = *PI;
   1137     ResultStr += ", ";
   1138     if (PDecl->getType()->isObjCQualifiedIdType()) {
   1139       ResultStr += "id ";
   1140       ResultStr += PDecl->getNameAsString();
   1141     } else {
   1142       std::string Name = PDecl->getNameAsString();
   1143       QualType QT = PDecl->getType();
   1144       // Make sure we convert "t (^)(...)" to "t (*)(...)".
   1145       (void)convertBlockPointerToFunctionPointer(QT);
   1146       QT.getAsStringInternal(Name, Context->getPrintingPolicy());
   1147       ResultStr += Name;
   1148     }
   1149   }
   1150   if (OMD->isVariadic())
   1151     ResultStr += ", ...";
   1152   ResultStr += ") ";
   1153 
   1154   if (FPRetType) {
   1155     ResultStr += ")"; // close the precedence "scope" for "*".
   1156 
   1157     // Now, emit the argument types (if any).
   1158     if (const FunctionProtoType *FT = dyn_cast<FunctionProtoType>(FPRetType)) {
   1159       ResultStr += "(";
   1160       for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) {
   1161         if (i) ResultStr += ", ";
   1162         std::string ParamStr = FT->getArgType(i).getAsString(
   1163           Context->getPrintingPolicy());
   1164         ResultStr += ParamStr;
   1165       }
   1166       if (FT->isVariadic()) {
   1167         if (FT->getNumArgs()) ResultStr += ", ";
   1168         ResultStr += "...";
   1169       }
   1170       ResultStr += ")";
   1171     } else {
   1172       ResultStr += "()";
   1173     }
   1174   }
   1175 }
   1176 void RewriteObjC::RewriteImplementationDecl(Decl *OID) {
   1177   ObjCImplementationDecl *IMD = dyn_cast<ObjCImplementationDecl>(OID);
   1178   ObjCCategoryImplDecl *CID = dyn_cast<ObjCCategoryImplDecl>(OID);
   1179 
   1180   InsertText(IMD ? IMD->getLocStart() : CID->getLocStart(), "// ");
   1181 
   1182   for (ObjCCategoryImplDecl::instmeth_iterator
   1183        I = IMD ? IMD->instmeth_begin() : CID->instmeth_begin(),
   1184        E = IMD ? IMD->instmeth_end() : CID->instmeth_end();
   1185        I != E; ++I) {
   1186     std::string ResultStr;
   1187     ObjCMethodDecl *OMD = *I;
   1188     RewriteObjCMethodDecl(OMD->getClassInterface(), OMD, ResultStr);
   1189     SourceLocation LocStart = OMD->getLocStart();
   1190     SourceLocation LocEnd = OMD->getCompoundBody()->getLocStart();
   1191 
   1192     const char *startBuf = SM->getCharacterData(LocStart);
   1193     const char *endBuf = SM->getCharacterData(LocEnd);
   1194     ReplaceText(LocStart, endBuf-startBuf, ResultStr);
   1195   }
   1196 
   1197   for (ObjCCategoryImplDecl::classmeth_iterator
   1198        I = IMD ? IMD->classmeth_begin() : CID->classmeth_begin(),
   1199        E = IMD ? IMD->classmeth_end() : CID->classmeth_end();
   1200        I != E; ++I) {
   1201     std::string ResultStr;
   1202     ObjCMethodDecl *OMD = *I;
   1203     RewriteObjCMethodDecl(OMD->getClassInterface(), OMD, ResultStr);
   1204     SourceLocation LocStart = OMD->getLocStart();
   1205     SourceLocation LocEnd = OMD->getCompoundBody()->getLocStart();
   1206 
   1207     const char *startBuf = SM->getCharacterData(LocStart);
   1208     const char *endBuf = SM->getCharacterData(LocEnd);
   1209     ReplaceText(LocStart, endBuf-startBuf, ResultStr);
   1210   }
   1211   for (ObjCCategoryImplDecl::propimpl_iterator
   1212        I = IMD ? IMD->propimpl_begin() : CID->propimpl_begin(),
   1213        E = IMD ? IMD->propimpl_end() : CID->propimpl_end();
   1214        I != E; ++I) {
   1215     RewritePropertyImplDecl(*I, IMD, CID);
   1216   }
   1217 
   1218   InsertText(IMD ? IMD->getLocEnd() : CID->getLocEnd(), "// ");
   1219 }
   1220 
   1221 void RewriteObjC::RewriteInterfaceDecl(ObjCInterfaceDecl *ClassDecl) {
   1222   std::string ResultStr;
   1223   if (!ObjCForwardDecls.count(ClassDecl->getCanonicalDecl())) {
   1224     // we haven't seen a forward decl - generate a typedef.
   1225     ResultStr = "#ifndef _REWRITER_typedef_";
   1226     ResultStr += ClassDecl->getNameAsString();
   1227     ResultStr += "\n";
   1228     ResultStr += "#define _REWRITER_typedef_";
   1229     ResultStr += ClassDecl->getNameAsString();
   1230     ResultStr += "\n";
   1231     ResultStr += "typedef struct objc_object ";
   1232     ResultStr += ClassDecl->getNameAsString();
   1233     ResultStr += ";\n#endif\n";
   1234     // Mark this typedef as having been generated.
   1235     ObjCForwardDecls.insert(ClassDecl->getCanonicalDecl());
   1236   }
   1237   RewriteObjCInternalStruct(ClassDecl, ResultStr);
   1238 
   1239   for (ObjCInterfaceDecl::prop_iterator I = ClassDecl->prop_begin(),
   1240          E = ClassDecl->prop_end(); I != E; ++I)
   1241     RewriteProperty(*I);
   1242   for (ObjCInterfaceDecl::instmeth_iterator
   1243          I = ClassDecl->instmeth_begin(), E = ClassDecl->instmeth_end();
   1244        I != E; ++I)
   1245     RewriteMethodDeclaration(*I);
   1246   for (ObjCInterfaceDecl::classmeth_iterator
   1247          I = ClassDecl->classmeth_begin(), E = ClassDecl->classmeth_end();
   1248        I != E; ++I)
   1249     RewriteMethodDeclaration(*I);
   1250 
   1251   // Lastly, comment out the @end.
   1252   ReplaceText(ClassDecl->getAtEndRange().getBegin(), strlen("@end"),
   1253               "/* @end */");
   1254 }
   1255 
   1256 Stmt *RewriteObjC::RewritePropertyOrImplicitSetter(PseudoObjectExpr *PseudoOp) {
   1257   SourceRange OldRange = PseudoOp->getSourceRange();
   1258 
   1259   // We just magically know some things about the structure of this
   1260   // expression.
   1261   ObjCMessageExpr *OldMsg =
   1262     cast<ObjCMessageExpr>(PseudoOp->getSemanticExpr(
   1263                             PseudoOp->getNumSemanticExprs() - 1));
   1264 
   1265   // Because the rewriter doesn't allow us to rewrite rewritten code,
   1266   // we need to suppress rewriting the sub-statements.
   1267   Expr *Base, *RHS;
   1268   {
   1269     DisableReplaceStmtScope S(*this);
   1270 
   1271     // Rebuild the base expression if we have one.
   1272     Base = 0;
   1273     if (OldMsg->getReceiverKind() == ObjCMessageExpr::Instance) {
   1274       Base = OldMsg->getInstanceReceiver();
   1275       Base = cast<OpaqueValueExpr>(Base)->getSourceExpr();
   1276       Base = cast<Expr>(RewriteFunctionBodyOrGlobalInitializer(Base));
   1277     }
   1278 
   1279     // Rebuild the RHS.
   1280     RHS = cast<BinaryOperator>(PseudoOp->getSyntacticForm())->getRHS();
   1281     RHS = cast<OpaqueValueExpr>(RHS)->getSourceExpr();
   1282     RHS = cast<Expr>(RewriteFunctionBodyOrGlobalInitializer(RHS));
   1283   }
   1284 
   1285   // TODO: avoid this copy.
   1286   SmallVector<SourceLocation, 1> SelLocs;
   1287   OldMsg->getSelectorLocs(SelLocs);
   1288 
   1289   ObjCMessageExpr *NewMsg = 0;
   1290   switch (OldMsg->getReceiverKind()) {
   1291   case ObjCMessageExpr::Class:
   1292     NewMsg = ObjCMessageExpr::Create(*Context, OldMsg->getType(),
   1293                                      OldMsg->getValueKind(),
   1294                                      OldMsg->getLeftLoc(),
   1295                                      OldMsg->getClassReceiverTypeInfo(),
   1296                                      OldMsg->getSelector(),
   1297                                      SelLocs,
   1298                                      OldMsg->getMethodDecl(),
   1299                                      RHS,
   1300                                      OldMsg->getRightLoc(),
   1301                                      OldMsg->isImplicit());
   1302     break;
   1303 
   1304   case ObjCMessageExpr::Instance:
   1305     NewMsg = ObjCMessageExpr::Create(*Context, OldMsg->getType(),
   1306                                      OldMsg->getValueKind(),
   1307                                      OldMsg->getLeftLoc(),
   1308                                      Base,
   1309                                      OldMsg->getSelector(),
   1310                                      SelLocs,
   1311                                      OldMsg->getMethodDecl(),
   1312                                      RHS,
   1313                                      OldMsg->getRightLoc(),
   1314                                      OldMsg->isImplicit());
   1315     break;
   1316 
   1317   case ObjCMessageExpr::SuperClass:
   1318   case ObjCMessageExpr::SuperInstance:
   1319     NewMsg = ObjCMessageExpr::Create(*Context, OldMsg->getType(),
   1320                                      OldMsg->getValueKind(),
   1321                                      OldMsg->getLeftLoc(),
   1322                                      OldMsg->getSuperLoc(),
   1323                  OldMsg->getReceiverKind() == ObjCMessageExpr::SuperInstance,
   1324                                      OldMsg->getSuperType(),
   1325                                      OldMsg->getSelector(),
   1326                                      SelLocs,
   1327                                      OldMsg->getMethodDecl(),
   1328                                      RHS,
   1329                                      OldMsg->getRightLoc(),
   1330                                      OldMsg->isImplicit());
   1331     break;
   1332   }
   1333 
   1334   Stmt *Replacement = SynthMessageExpr(NewMsg);
   1335   ReplaceStmtWithRange(PseudoOp, Replacement, OldRange);
   1336   return Replacement;
   1337 }
   1338 
   1339 Stmt *RewriteObjC::RewritePropertyOrImplicitGetter(PseudoObjectExpr *PseudoOp) {
   1340   SourceRange OldRange = PseudoOp->getSourceRange();
   1341 
   1342   // We just magically know some things about the structure of this
   1343   // expression.
   1344   ObjCMessageExpr *OldMsg =
   1345     cast<ObjCMessageExpr>(PseudoOp->getResultExpr()->IgnoreImplicit());
   1346 
   1347   // Because the rewriter doesn't allow us to rewrite rewritten code,
   1348   // we need to suppress rewriting the sub-statements.
   1349   Expr *Base = 0;
   1350   {
   1351     DisableReplaceStmtScope S(*this);
   1352 
   1353     // Rebuild the base expression if we have one.
   1354     if (OldMsg->getReceiverKind() == ObjCMessageExpr::Instance) {
   1355       Base = OldMsg->getInstanceReceiver();
   1356       Base = cast<OpaqueValueExpr>(Base)->getSourceExpr();
   1357       Base = cast<Expr>(RewriteFunctionBodyOrGlobalInitializer(Base));
   1358     }
   1359   }
   1360 
   1361   // Intentionally empty.
   1362   SmallVector<SourceLocation, 1> SelLocs;
   1363   SmallVector<Expr*, 1> Args;
   1364 
   1365   ObjCMessageExpr *NewMsg = 0;
   1366   switch (OldMsg->getReceiverKind()) {
   1367   case ObjCMessageExpr::Class:
   1368     NewMsg = ObjCMessageExpr::Create(*Context, OldMsg->getType(),
   1369                                      OldMsg->getValueKind(),
   1370                                      OldMsg->getLeftLoc(),
   1371                                      OldMsg->getClassReceiverTypeInfo(),
   1372                                      OldMsg->getSelector(),
   1373                                      SelLocs,
   1374                                      OldMsg->getMethodDecl(),
   1375                                      Args,
   1376                                      OldMsg->getRightLoc(),
   1377                                      OldMsg->isImplicit());
   1378     break;
   1379 
   1380   case ObjCMessageExpr::Instance:
   1381     NewMsg = ObjCMessageExpr::Create(*Context, OldMsg->getType(),
   1382                                      OldMsg->getValueKind(),
   1383                                      OldMsg->getLeftLoc(),
   1384                                      Base,
   1385                                      OldMsg->getSelector(),
   1386                                      SelLocs,
   1387                                      OldMsg->getMethodDecl(),
   1388                                      Args,
   1389                                      OldMsg->getRightLoc(),
   1390                                      OldMsg->isImplicit());
   1391     break;
   1392 
   1393   case ObjCMessageExpr::SuperClass:
   1394   case ObjCMessageExpr::SuperInstance:
   1395     NewMsg = ObjCMessageExpr::Create(*Context, OldMsg->getType(),
   1396                                      OldMsg->getValueKind(),
   1397                                      OldMsg->getLeftLoc(),
   1398                                      OldMsg->getSuperLoc(),
   1399                  OldMsg->getReceiverKind() == ObjCMessageExpr::SuperInstance,
   1400                                      OldMsg->getSuperType(),
   1401                                      OldMsg->getSelector(),
   1402                                      SelLocs,
   1403                                      OldMsg->getMethodDecl(),
   1404                                      Args,
   1405                                      OldMsg->getRightLoc(),
   1406                                      OldMsg->isImplicit());
   1407     break;
   1408   }
   1409 
   1410   Stmt *Replacement = SynthMessageExpr(NewMsg);
   1411   ReplaceStmtWithRange(PseudoOp, Replacement, OldRange);
   1412   return Replacement;
   1413 }
   1414 
   1415 /// SynthCountByEnumWithState - To print:
   1416 /// ((unsigned int (*)
   1417 ///  (id, SEL, struct __objcFastEnumerationState *, id *, unsigned int))
   1418 ///  (void *)objc_msgSend)((id)l_collection,
   1419 ///                        sel_registerName(
   1420 ///                          "countByEnumeratingWithState:objects:count:"),
   1421 ///                        &enumState,
   1422 ///                        (id *)__rw_items, (unsigned int)16)
   1423 ///
   1424 void RewriteObjC::SynthCountByEnumWithState(std::string &buf) {
   1425   buf += "((unsigned int (*) (id, SEL, struct __objcFastEnumerationState *, "
   1426   "id *, unsigned int))(void *)objc_msgSend)";
   1427   buf += "\n\t\t";
   1428   buf += "((id)l_collection,\n\t\t";
   1429   buf += "sel_registerName(\"countByEnumeratingWithState:objects:count:\"),";
   1430   buf += "\n\t\t";
   1431   buf += "&enumState, "
   1432          "(id *)__rw_items, (unsigned int)16)";
   1433 }
   1434 
   1435 /// RewriteBreakStmt - Rewrite for a break-stmt inside an ObjC2's foreach
   1436 /// statement to exit to its outer synthesized loop.
   1437 ///
   1438 Stmt *RewriteObjC::RewriteBreakStmt(BreakStmt *S) {
   1439   if (Stmts.empty() || !isa<ObjCForCollectionStmt>(Stmts.back()))
   1440     return S;
   1441   // replace break with goto __break_label
   1442   std::string buf;
   1443 
   1444   SourceLocation startLoc = S->getLocStart();
   1445   buf = "goto __break_label_";
   1446   buf += utostr(ObjCBcLabelNo.back());
   1447   ReplaceText(startLoc, strlen("break"), buf);
   1448 
   1449   return 0;
   1450 }
   1451 
   1452 /// RewriteContinueStmt - Rewrite for a continue-stmt inside an ObjC2's foreach
   1453 /// statement to continue with its inner synthesized loop.
   1454 ///
   1455 Stmt *RewriteObjC::RewriteContinueStmt(ContinueStmt *S) {
   1456   if (Stmts.empty() || !isa<ObjCForCollectionStmt>(Stmts.back()))
   1457     return S;
   1458   // replace continue with goto __continue_label
   1459   std::string buf;
   1460 
   1461   SourceLocation startLoc = S->getLocStart();
   1462   buf = "goto __continue_label_";
   1463   buf += utostr(ObjCBcLabelNo.back());
   1464   ReplaceText(startLoc, strlen("continue"), buf);
   1465 
   1466   return 0;
   1467 }
   1468 
   1469 /// RewriteObjCForCollectionStmt - Rewriter for ObjC2's foreach statement.
   1470 ///  It rewrites:
   1471 /// for ( type elem in collection) { stmts; }
   1472 
   1473 /// Into:
   1474 /// {
   1475 ///   type elem;
   1476 ///   struct __objcFastEnumerationState enumState = { 0 };
   1477 ///   id __rw_items[16];
   1478 ///   id l_collection = (id)collection;
   1479 ///   unsigned long limit = [l_collection countByEnumeratingWithState:&enumState
   1480 ///                                       objects:__rw_items count:16];
   1481 /// if (limit) {
   1482 ///   unsigned long startMutations = *enumState.mutationsPtr;
   1483 ///   do {
   1484 ///        unsigned long counter = 0;
   1485 ///        do {
   1486 ///             if (startMutations != *enumState.mutationsPtr)
   1487 ///               objc_enumerationMutation(l_collection);
   1488 ///             elem = (type)enumState.itemsPtr[counter++];
   1489 ///             stmts;
   1490 ///             __continue_label: ;
   1491 ///        } while (counter < limit);
   1492 ///   } while (limit = [l_collection countByEnumeratingWithState:&enumState
   1493 ///                                  objects:__rw_items count:16]);
   1494 ///   elem = nil;
   1495 ///   __break_label: ;
   1496 ///  }
   1497 ///  else
   1498 ///       elem = nil;
   1499 ///  }
   1500 ///
   1501 Stmt *RewriteObjC::RewriteObjCForCollectionStmt(ObjCForCollectionStmt *S,
   1502                                                 SourceLocation OrigEnd) {
   1503   assert(!Stmts.empty() && "ObjCForCollectionStmt - Statement stack empty");
   1504   assert(isa<ObjCForCollectionStmt>(Stmts.back()) &&
   1505          "ObjCForCollectionStmt Statement stack mismatch");
   1506   assert(!ObjCBcLabelNo.empty() &&
   1507          "ObjCForCollectionStmt - Label No stack empty");
   1508 
   1509   SourceLocation startLoc = S->getLocStart();
   1510   const char *startBuf = SM->getCharacterData(startLoc);
   1511   StringRef elementName;
   1512   std::string elementTypeAsString;
   1513   std::string buf;
   1514   buf = "\n{\n\t";
   1515   if (DeclStmt *DS = dyn_cast<DeclStmt>(S->getElement())) {
   1516     // type elem;
   1517     NamedDecl* D = cast<NamedDecl>(DS->getSingleDecl());
   1518     QualType ElementType = cast<ValueDecl>(D)->getType();
   1519     if (ElementType->isObjCQualifiedIdType() ||
   1520         ElementType->isObjCQualifiedInterfaceType())
   1521       // Simply use 'id' for all qualified types.
   1522       elementTypeAsString = "id";
   1523     else
   1524       elementTypeAsString = ElementType.getAsString(Context->getPrintingPolicy());
   1525     buf += elementTypeAsString;
   1526     buf += " ";
   1527     elementName = D->getName();
   1528     buf += elementName;
   1529     buf += ";\n\t";
   1530   }
   1531   else {
   1532     DeclRefExpr *DR = cast<DeclRefExpr>(S->getElement());
   1533     elementName = DR->getDecl()->getName();
   1534     ValueDecl *VD = cast<ValueDecl>(DR->getDecl());
   1535     if (VD->getType()->isObjCQualifiedIdType() ||
   1536         VD->getType()->isObjCQualifiedInterfaceType())
   1537       // Simply use 'id' for all qualified types.
   1538       elementTypeAsString = "id";
   1539     else
   1540       elementTypeAsString = VD->getType().getAsString(Context->getPrintingPolicy());
   1541   }
   1542 
   1543   // struct __objcFastEnumerationState enumState = { 0 };
   1544   buf += "struct __objcFastEnumerationState enumState = { 0 };\n\t";
   1545   // id __rw_items[16];
   1546   buf += "id __rw_items[16];\n\t";
   1547   // id l_collection = (id)
   1548   buf += "id l_collection = (id)";
   1549   // Find start location of 'collection' the hard way!
   1550   const char *startCollectionBuf = startBuf;
   1551   startCollectionBuf += 3;  // skip 'for'
   1552   startCollectionBuf = strchr(startCollectionBuf, '(');
   1553   startCollectionBuf++; // skip '('
   1554   // find 'in' and skip it.
   1555   while (*startCollectionBuf != ' ' ||
   1556          *(startCollectionBuf+1) != 'i' || *(startCollectionBuf+2) != 'n' ||
   1557          (*(startCollectionBuf+3) != ' ' &&
   1558           *(startCollectionBuf+3) != '[' && *(startCollectionBuf+3) != '('))
   1559     startCollectionBuf++;
   1560   startCollectionBuf += 3;
   1561 
   1562   // Replace: "for (type element in" with string constructed thus far.
   1563   ReplaceText(startLoc, startCollectionBuf - startBuf, buf);
   1564   // Replace ')' in for '(' type elem in collection ')' with ';'
   1565   SourceLocation rightParenLoc = S->getRParenLoc();
   1566   const char *rparenBuf = SM->getCharacterData(rightParenLoc);
   1567   SourceLocation lparenLoc = startLoc.getLocWithOffset(rparenBuf-startBuf);
   1568   buf = ";\n\t";
   1569 
   1570   // unsigned long limit = [l_collection countByEnumeratingWithState:&enumState
   1571   //                                   objects:__rw_items count:16];
   1572   // which is synthesized into:
   1573   // unsigned int limit =
   1574   // ((unsigned int (*)
   1575   //  (id, SEL, struct __objcFastEnumerationState *, id *, unsigned int))
   1576   //  (void *)objc_msgSend)((id)l_collection,
   1577   //                        sel_registerName(
   1578   //                          "countByEnumeratingWithState:objects:count:"),
   1579   //                        (struct __objcFastEnumerationState *)&state,
   1580   //                        (id *)__rw_items, (unsigned int)16);
   1581   buf += "unsigned long limit =\n\t\t";
   1582   SynthCountByEnumWithState(buf);
   1583   buf += ";\n\t";
   1584   /// if (limit) {
   1585   ///   unsigned long startMutations = *enumState.mutationsPtr;
   1586   ///   do {
   1587   ///        unsigned long counter = 0;
   1588   ///        do {
   1589   ///             if (startMutations != *enumState.mutationsPtr)
   1590   ///               objc_enumerationMutation(l_collection);
   1591   ///             elem = (type)enumState.itemsPtr[counter++];
   1592   buf += "if (limit) {\n\t";
   1593   buf += "unsigned long startMutations = *enumState.mutationsPtr;\n\t";
   1594   buf += "do {\n\t\t";
   1595   buf += "unsigned long counter = 0;\n\t\t";
   1596   buf += "do {\n\t\t\t";
   1597   buf += "if (startMutations != *enumState.mutationsPtr)\n\t\t\t\t";
   1598   buf += "objc_enumerationMutation(l_collection);\n\t\t\t";
   1599   buf += elementName;
   1600   buf += " = (";
   1601   buf += elementTypeAsString;
   1602   buf += ")enumState.itemsPtr[counter++];";
   1603   // Replace ')' in for '(' type elem in collection ')' with all of these.
   1604   ReplaceText(lparenLoc, 1, buf);
   1605 
   1606   ///            __continue_label: ;
   1607   ///        } while (counter < limit);
   1608   ///   } while (limit = [l_collection countByEnumeratingWithState:&enumState
   1609   ///                                  objects:__rw_items count:16]);
   1610   ///   elem = nil;
   1611   ///   __break_label: ;
   1612   ///  }
   1613   ///  else
   1614   ///       elem = nil;
   1615   ///  }
   1616   ///
   1617   buf = ";\n\t";
   1618   buf += "__continue_label_";
   1619   buf += utostr(ObjCBcLabelNo.back());
   1620   buf += ": ;";
   1621   buf += "\n\t\t";
   1622   buf += "} while (counter < limit);\n\t";
   1623   buf += "} while (limit = ";
   1624   SynthCountByEnumWithState(buf);
   1625   buf += ");\n\t";
   1626   buf += elementName;
   1627   buf += " = ((";
   1628   buf += elementTypeAsString;
   1629   buf += ")0);\n\t";
   1630   buf += "__break_label_";
   1631   buf += utostr(ObjCBcLabelNo.back());
   1632   buf += ": ;\n\t";
   1633   buf += "}\n\t";
   1634   buf += "else\n\t\t";
   1635   buf += elementName;
   1636   buf += " = ((";
   1637   buf += elementTypeAsString;
   1638   buf += ")0);\n\t";
   1639   buf += "}\n";
   1640 
   1641   // Insert all these *after* the statement body.
   1642   // FIXME: If this should support Obj-C++, support CXXTryStmt
   1643   if (isa<CompoundStmt>(S->getBody())) {
   1644     SourceLocation endBodyLoc = OrigEnd.getLocWithOffset(1);
   1645     InsertText(endBodyLoc, buf);
   1646   } else {
   1647     /* Need to treat single statements specially. For example:
   1648      *
   1649      *     for (A *a in b) if (stuff()) break;
   1650      *     for (A *a in b) xxxyy;
   1651      *
   1652      * The following code simply scans ahead to the semi to find the actual end.
   1653      */
   1654     const char *stmtBuf = SM->getCharacterData(OrigEnd);
   1655     const char *semiBuf = strchr(stmtBuf, ';');
   1656     assert(semiBuf && "Can't find ';'");
   1657     SourceLocation endBodyLoc = OrigEnd.getLocWithOffset(semiBuf-stmtBuf+1);
   1658     InsertText(endBodyLoc, buf);
   1659   }
   1660   Stmts.pop_back();
   1661   ObjCBcLabelNo.pop_back();
   1662   return 0;
   1663 }
   1664 
   1665 /// RewriteObjCSynchronizedStmt -
   1666 /// This routine rewrites @synchronized(expr) stmt;
   1667 /// into:
   1668 /// objc_sync_enter(expr);
   1669 /// @try stmt @finally { objc_sync_exit(expr); }
   1670 ///
   1671 Stmt *RewriteObjC::RewriteObjCSynchronizedStmt(ObjCAtSynchronizedStmt *S) {
   1672   // Get the start location and compute the semi location.
   1673   SourceLocation startLoc = S->getLocStart();
   1674   const char *startBuf = SM->getCharacterData(startLoc);
   1675 
   1676   assert((*startBuf == '@') && "bogus @synchronized location");
   1677 
   1678   std::string buf;
   1679   buf = "objc_sync_enter((id)";
   1680   const char *lparenBuf = startBuf;
   1681   while (*lparenBuf != '(') lparenBuf++;
   1682   ReplaceText(startLoc, lparenBuf-startBuf+1, buf);
   1683   // We can't use S->getSynchExpr()->getLocEnd() to find the end location, since
   1684   // the sync expression is typically a message expression that's already
   1685   // been rewritten! (which implies the SourceLocation's are invalid).
   1686   SourceLocation endLoc = S->getSynchBody()->getLocStart();
   1687   const char *endBuf = SM->getCharacterData(endLoc);
   1688   while (*endBuf != ')') endBuf--;
   1689   SourceLocation rparenLoc = startLoc.getLocWithOffset(endBuf-startBuf);
   1690   buf = ");\n";
   1691   // declare a new scope with two variables, _stack and _rethrow.
   1692   buf += "/* @try scope begin */ \n{ struct _objc_exception_data {\n";
   1693   buf += "int buf[18/*32-bit i386*/];\n";
   1694   buf += "char *pointers[4];} _stack;\n";
   1695   buf += "id volatile _rethrow = 0;\n";
   1696   buf += "objc_exception_try_enter(&_stack);\n";
   1697   buf += "if (!_setjmp(_stack.buf)) /* @try block continue */\n";
   1698   ReplaceText(rparenLoc, 1, buf);
   1699   startLoc = S->getSynchBody()->getLocEnd();
   1700   startBuf = SM->getCharacterData(startLoc);
   1701 
   1702   assert((*startBuf == '}') && "bogus @synchronized block");
   1703   SourceLocation lastCurlyLoc = startLoc;
   1704   buf = "}\nelse {\n";
   1705   buf += "  _rethrow = objc_exception_extract(&_stack);\n";
   1706   buf += "}\n";
   1707   buf += "{ /* implicit finally clause */\n";
   1708   buf += "  if (!_rethrow) objc_exception_try_exit(&_stack);\n";
   1709 
   1710   std::string syncBuf;
   1711   syncBuf += " objc_sync_exit(";
   1712 
   1713   Expr *syncExpr = S->getSynchExpr();
   1714   CastKind CK = syncExpr->getType()->isObjCObjectPointerType()
   1715                   ? CK_BitCast :
   1716                 syncExpr->getType()->isBlockPointerType()
   1717                   ? CK_BlockPointerToObjCPointerCast
   1718                   : CK_CPointerToObjCPointerCast;
   1719   syncExpr = NoTypeInfoCStyleCastExpr(Context, Context->getObjCIdType(),
   1720                                       CK, syncExpr);
   1721   std::string syncExprBufS;
   1722   llvm::raw_string_ostream syncExprBuf(syncExprBufS);
   1723   syncExpr->printPretty(syncExprBuf, 0, PrintingPolicy(LangOpts));
   1724   syncBuf += syncExprBuf.str();
   1725   syncBuf += ");";
   1726 
   1727   buf += syncBuf;
   1728   buf += "\n  if (_rethrow) objc_exception_throw(_rethrow);\n";
   1729   buf += "}\n";
   1730   buf += "}";
   1731 
   1732   ReplaceText(lastCurlyLoc, 1, buf);
   1733 
   1734   bool hasReturns = false;
   1735   HasReturnStmts(S->getSynchBody(), hasReturns);
   1736   if (hasReturns)
   1737     RewriteSyncReturnStmts(S->getSynchBody(), syncBuf);
   1738 
   1739   return 0;
   1740 }
   1741 
   1742 void RewriteObjC::WarnAboutReturnGotoStmts(Stmt *S)
   1743 {
   1744   // Perform a bottom up traversal of all children.
   1745   for (Stmt::child_range CI = S->children(); CI; ++CI)
   1746     if (*CI)
   1747       WarnAboutReturnGotoStmts(*CI);
   1748 
   1749   if (isa<ReturnStmt>(S) || isa<GotoStmt>(S)) {
   1750     Diags.Report(Context->getFullLoc(S->getLocStart()),
   1751                  TryFinallyContainsReturnDiag);
   1752   }
   1753   return;
   1754 }
   1755 
   1756 void RewriteObjC::HasReturnStmts(Stmt *S, bool &hasReturns)
   1757 {
   1758   // Perform a bottom up traversal of all children.
   1759   for (Stmt::child_range CI = S->children(); CI; ++CI)
   1760    if (*CI)
   1761      HasReturnStmts(*CI, hasReturns);
   1762 
   1763  if (isa<ReturnStmt>(S))
   1764    hasReturns = true;
   1765  return;
   1766 }
   1767 
   1768 void RewriteObjC::RewriteTryReturnStmts(Stmt *S) {
   1769  // Perform a bottom up traversal of all children.
   1770  for (Stmt::child_range CI = S->children(); CI; ++CI)
   1771    if (*CI) {
   1772      RewriteTryReturnStmts(*CI);
   1773    }
   1774  if (isa<ReturnStmt>(S)) {
   1775    SourceLocation startLoc = S->getLocStart();
   1776    const char *startBuf = SM->getCharacterData(startLoc);
   1777 
   1778    const char *semiBuf = strchr(startBuf, ';');
   1779    assert((*semiBuf == ';') && "RewriteTryReturnStmts: can't find ';'");
   1780    SourceLocation onePastSemiLoc = startLoc.getLocWithOffset(semiBuf-startBuf+1);
   1781 
   1782    std::string buf;
   1783    buf = "{ objc_exception_try_exit(&_stack); return";
   1784 
   1785    ReplaceText(startLoc, 6, buf);
   1786    InsertText(onePastSemiLoc, "}");
   1787  }
   1788  return;
   1789 }
   1790 
   1791 void RewriteObjC::RewriteSyncReturnStmts(Stmt *S, std::string syncExitBuf) {
   1792   // Perform a bottom up traversal of all children.
   1793   for (Stmt::child_range CI = S->children(); CI; ++CI)
   1794     if (*CI) {
   1795       RewriteSyncReturnStmts(*CI, syncExitBuf);
   1796     }
   1797   if (isa<ReturnStmt>(S)) {
   1798     SourceLocation startLoc = S->getLocStart();
   1799     const char *startBuf = SM->getCharacterData(startLoc);
   1800 
   1801     const char *semiBuf = strchr(startBuf, ';');
   1802     assert((*semiBuf == ';') && "RewriteSyncReturnStmts: can't find ';'");
   1803     SourceLocation onePastSemiLoc = startLoc.getLocWithOffset(semiBuf-startBuf+1);
   1804 
   1805     std::string buf;
   1806     buf = "{ objc_exception_try_exit(&_stack);";
   1807     buf += syncExitBuf;
   1808     buf += " return";
   1809 
   1810     ReplaceText(startLoc, 6, buf);
   1811     InsertText(onePastSemiLoc, "}");
   1812   }
   1813   return;
   1814 }
   1815 
   1816 Stmt *RewriteObjC::RewriteObjCTryStmt(ObjCAtTryStmt *S) {
   1817   // Get the start location and compute the semi location.
   1818   SourceLocation startLoc = S->getLocStart();
   1819   const char *startBuf = SM->getCharacterData(startLoc);
   1820 
   1821   assert((*startBuf == '@') && "bogus @try location");
   1822 
   1823   std::string buf;
   1824   // declare a new scope with two variables, _stack and _rethrow.
   1825   buf = "/* @try scope begin */ { struct _objc_exception_data {\n";
   1826   buf += "int buf[18/*32-bit i386*/];\n";
   1827   buf += "char *pointers[4];} _stack;\n";
   1828   buf += "id volatile _rethrow = 0;\n";
   1829   buf += "objc_exception_try_enter(&_stack);\n";
   1830   buf += "if (!_setjmp(_stack.buf)) /* @try block continue */\n";
   1831 
   1832   ReplaceText(startLoc, 4, buf);
   1833 
   1834   startLoc = S->getTryBody()->getLocEnd();
   1835   startBuf = SM->getCharacterData(startLoc);
   1836 
   1837   assert((*startBuf == '}') && "bogus @try block");
   1838 
   1839   SourceLocation lastCurlyLoc = startLoc;
   1840   if (S->getNumCatchStmts()) {
   1841     startLoc = startLoc.getLocWithOffset(1);
   1842     buf = " /* @catch begin */ else {\n";
   1843     buf += " id _caught = objc_exception_extract(&_stack);\n";
   1844     buf += " objc_exception_try_enter (&_stack);\n";
   1845     buf += " if (_setjmp(_stack.buf))\n";
   1846     buf += "   _rethrow = objc_exception_extract(&_stack);\n";
   1847     buf += " else { /* @catch continue */";
   1848 
   1849     InsertText(startLoc, buf);
   1850   } else { /* no catch list */
   1851     buf = "}\nelse {\n";
   1852     buf += "  _rethrow = objc_exception_extract(&_stack);\n";
   1853     buf += "}";
   1854     ReplaceText(lastCurlyLoc, 1, buf);
   1855   }
   1856   Stmt *lastCatchBody = 0;
   1857   for (unsigned I = 0, N = S->getNumCatchStmts(); I != N; ++I) {
   1858     ObjCAtCatchStmt *Catch = S->getCatchStmt(I);
   1859     VarDecl *catchDecl = Catch->getCatchParamDecl();
   1860 
   1861     if (I == 0)
   1862       buf = "if ("; // we are generating code for the first catch clause
   1863     else
   1864       buf = "else if (";
   1865     startLoc = Catch->getLocStart();
   1866     startBuf = SM->getCharacterData(startLoc);
   1867 
   1868     assert((*startBuf == '@') && "bogus @catch location");
   1869 
   1870     const char *lParenLoc = strchr(startBuf, '(');
   1871 
   1872     if (Catch->hasEllipsis()) {
   1873       // Now rewrite the body...
   1874       lastCatchBody = Catch->getCatchBody();
   1875       SourceLocation bodyLoc = lastCatchBody->getLocStart();
   1876       const char *bodyBuf = SM->getCharacterData(bodyLoc);
   1877       assert(*SM->getCharacterData(Catch->getRParenLoc()) == ')' &&
   1878              "bogus @catch paren location");
   1879       assert((*bodyBuf == '{') && "bogus @catch body location");
   1880 
   1881       buf += "1) { id _tmp = _caught;";
   1882       Rewrite.ReplaceText(startLoc, bodyBuf-startBuf+1, buf);
   1883     } else if (catchDecl) {
   1884       QualType t = catchDecl->getType();
   1885       if (t == Context->getObjCIdType()) {
   1886         buf += "1) { ";
   1887         ReplaceText(startLoc, lParenLoc-startBuf+1, buf);
   1888       } else if (const ObjCObjectPointerType *Ptr =
   1889                    t->getAs<ObjCObjectPointerType>()) {
   1890         // Should be a pointer to a class.
   1891         ObjCInterfaceDecl *IDecl = Ptr->getObjectType()->getInterface();
   1892         if (IDecl) {
   1893           buf += "objc_exception_match((struct objc_class *)objc_getClass(\"";
   1894           buf += IDecl->getNameAsString();
   1895           buf += "\"), (struct objc_object *)_caught)) { ";
   1896           ReplaceText(startLoc, lParenLoc-startBuf+1, buf);
   1897         }
   1898       }
   1899       // Now rewrite the body...
   1900       lastCatchBody = Catch->getCatchBody();
   1901       SourceLocation rParenLoc = Catch->getRParenLoc();
   1902       SourceLocation bodyLoc = lastCatchBody->getLocStart();
   1903       const char *bodyBuf = SM->getCharacterData(bodyLoc);
   1904       const char *rParenBuf = SM->getCharacterData(rParenLoc);
   1905       assert((*rParenBuf == ')') && "bogus @catch paren location");
   1906       assert((*bodyBuf == '{') && "bogus @catch body location");
   1907 
   1908       // Here we replace ") {" with "= _caught;" (which initializes and
   1909       // declares the @catch parameter).
   1910       ReplaceText(rParenLoc, bodyBuf-rParenBuf+1, " = _caught;");
   1911     } else {
   1912       llvm_unreachable("@catch rewrite bug");
   1913     }
   1914   }
   1915   // Complete the catch list...
   1916   if (lastCatchBody) {
   1917     SourceLocation bodyLoc = lastCatchBody->getLocEnd();
   1918     assert(*SM->getCharacterData(bodyLoc) == '}' &&
   1919            "bogus @catch body location");
   1920 
   1921     // Insert the last (implicit) else clause *before* the right curly brace.
   1922     bodyLoc = bodyLoc.getLocWithOffset(-1);
   1923     buf = "} /* last catch end */\n";
   1924     buf += "else {\n";
   1925     buf += " _rethrow = _caught;\n";
   1926     buf += " objc_exception_try_exit(&_stack);\n";
   1927     buf += "} } /* @catch end */\n";
   1928     if (!S->getFinallyStmt())
   1929       buf += "}\n";
   1930     InsertText(bodyLoc, buf);
   1931 
   1932     // Set lastCurlyLoc
   1933     lastCurlyLoc = lastCatchBody->getLocEnd();
   1934   }
   1935   if (ObjCAtFinallyStmt *finalStmt = S->getFinallyStmt()) {
   1936     startLoc = finalStmt->getLocStart();
   1937     startBuf = SM->getCharacterData(startLoc);
   1938     assert((*startBuf == '@') && "bogus @finally start");
   1939 
   1940     ReplaceText(startLoc, 8, "/* @finally */");
   1941 
   1942     Stmt *body = finalStmt->getFinallyBody();
   1943     SourceLocation startLoc = body->getLocStart();
   1944     SourceLocation endLoc = body->getLocEnd();
   1945     assert(*SM->getCharacterData(startLoc) == '{' &&
   1946            "bogus @finally body location");
   1947     assert(*SM->getCharacterData(endLoc) == '}' &&
   1948            "bogus @finally body location");
   1949 
   1950     startLoc = startLoc.getLocWithOffset(1);
   1951     InsertText(startLoc, " if (!_rethrow) objc_exception_try_exit(&_stack);\n");
   1952     endLoc = endLoc.getLocWithOffset(-1);
   1953     InsertText(endLoc, " if (_rethrow) objc_exception_throw(_rethrow);\n");
   1954 
   1955     // Set lastCurlyLoc
   1956     lastCurlyLoc = body->getLocEnd();
   1957 
   1958     // Now check for any return/continue/go statements within the @try.
   1959     WarnAboutReturnGotoStmts(S->getTryBody());
   1960   } else { /* no finally clause - make sure we synthesize an implicit one */
   1961     buf = "{ /* implicit finally clause */\n";
   1962     buf += " if (!_rethrow) objc_exception_try_exit(&_stack);\n";
   1963     buf += " if (_rethrow) objc_exception_throw(_rethrow);\n";
   1964     buf += "}";
   1965     ReplaceText(lastCurlyLoc, 1, buf);
   1966 
   1967     // Now check for any return/continue/go statements within the @try.
   1968     // The implicit finally clause won't called if the @try contains any
   1969     // jump statements.
   1970     bool hasReturns = false;
   1971     HasReturnStmts(S->getTryBody(), hasReturns);
   1972     if (hasReturns)
   1973       RewriteTryReturnStmts(S->getTryBody());
   1974   }
   1975   // Now emit the final closing curly brace...
   1976   lastCurlyLoc = lastCurlyLoc.getLocWithOffset(1);
   1977   InsertText(lastCurlyLoc, " } /* @try scope end */\n");
   1978   return 0;
   1979 }
   1980 
   1981 // This can't be done with ReplaceStmt(S, ThrowExpr), since
   1982 // the throw expression is typically a message expression that's already
   1983 // been rewritten! (which implies the SourceLocation's are invalid).
   1984 Stmt *RewriteObjC::RewriteObjCThrowStmt(ObjCAtThrowStmt *S) {
   1985   // Get the start location and compute the semi location.
   1986   SourceLocation startLoc = S->getLocStart();
   1987   const char *startBuf = SM->getCharacterData(startLoc);
   1988 
   1989   assert((*startBuf == '@') && "bogus @throw location");
   1990 
   1991   std::string buf;
   1992   /* void objc_exception_throw(id) __attribute__((noreturn)); */
   1993   if (S->getThrowExpr())
   1994     buf = "objc_exception_throw(";
   1995   else // add an implicit argument
   1996     buf = "objc_exception_throw(_caught";
   1997 
   1998   // handle "@  throw" correctly.
   1999   const char *wBuf = strchr(startBuf, 'w');
   2000   assert((*wBuf == 'w') && "@throw: can't find 'w'");
   2001   ReplaceText(startLoc, wBuf-startBuf+1, buf);
   2002 
   2003   const char *semiBuf = strchr(startBuf, ';');
   2004   assert((*semiBuf == ';') && "@throw: can't find ';'");
   2005   SourceLocation semiLoc = startLoc.getLocWithOffset(semiBuf-startBuf);
   2006   ReplaceText(semiLoc, 1, ");");
   2007   return 0;
   2008 }
   2009 
   2010 Stmt *RewriteObjC::RewriteAtEncode(ObjCEncodeExpr *Exp) {
   2011   // Create a new string expression.
   2012   QualType StrType = Context->getPointerType(Context->CharTy);
   2013   std::string StrEncoding;
   2014   Context->getObjCEncodingForType(Exp->getEncodedType(), StrEncoding);
   2015   Expr *Replacement = StringLiteral::Create(*Context, StrEncoding,
   2016                                             StringLiteral::Ascii, false,
   2017                                             StrType, SourceLocation());
   2018   ReplaceStmt(Exp, Replacement);
   2019 
   2020   // Replace this subexpr in the parent.
   2021   // delete Exp; leak for now, see RewritePropertyOrImplicitSetter() usage for more info.
   2022   return Replacement;
   2023 }
   2024 
   2025 Stmt *RewriteObjC::RewriteAtSelector(ObjCSelectorExpr *Exp) {
   2026   if (!SelGetUidFunctionDecl)
   2027     SynthSelGetUidFunctionDecl();
   2028   assert(SelGetUidFunctionDecl && "Can't find sel_registerName() decl");
   2029   // Create a call to sel_registerName("selName").
   2030   SmallVector<Expr*, 8> SelExprs;
   2031   QualType argType = Context->getPointerType(Context->CharTy);
   2032   SelExprs.push_back(StringLiteral::Create(*Context,
   2033                                            Exp->getSelector().getAsString(),
   2034                                            StringLiteral::Ascii, false,
   2035                                            argType, SourceLocation()));
   2036   CallExpr *SelExp = SynthesizeCallToFunctionDecl(SelGetUidFunctionDecl,
   2037                                                  &SelExprs[0], SelExprs.size());
   2038   ReplaceStmt(Exp, SelExp);
   2039   // delete Exp; leak for now, see RewritePropertyOrImplicitSetter() usage for more info.
   2040   return SelExp;
   2041 }
   2042 
   2043 CallExpr *RewriteObjC::SynthesizeCallToFunctionDecl(
   2044   FunctionDecl *FD, Expr **args, unsigned nargs, SourceLocation StartLoc,
   2045                                                     SourceLocation EndLoc) {
   2046   // Get the type, we will need to reference it in a couple spots.
   2047   QualType msgSendType = FD->getType();
   2048 
   2049   // Create a reference to the objc_msgSend() declaration.
   2050   DeclRefExpr *DRE = new (Context) DeclRefExpr(FD, false, msgSendType,
   2051                                                VK_LValue, SourceLocation());
   2052 
   2053   // Now, we cast the reference to a pointer to the objc_msgSend type.
   2054   QualType pToFunc = Context->getPointerType(msgSendType);
   2055   ImplicitCastExpr *ICE =
   2056     ImplicitCastExpr::Create(*Context, pToFunc, CK_FunctionToPointerDecay,
   2057                              DRE, 0, VK_RValue);
   2058 
   2059   const FunctionType *FT = msgSendType->getAs<FunctionType>();
   2060 
   2061   CallExpr *Exp =
   2062     new (Context) CallExpr(*Context, ICE, llvm::makeArrayRef(args, nargs),
   2063                            FT->getCallResultType(*Context),
   2064                            VK_RValue, EndLoc);
   2065   return Exp;
   2066 }
   2067 
   2068 static bool scanForProtocolRefs(const char *startBuf, const char *endBuf,
   2069                                 const char *&startRef, const char *&endRef) {
   2070   while (startBuf < endBuf) {
   2071     if (*startBuf == '<')
   2072       startRef = startBuf; // mark the start.
   2073     if (*startBuf == '>') {
   2074       if (startRef && *startRef == '<') {
   2075         endRef = startBuf; // mark the end.
   2076         return true;
   2077       }
   2078       return false;
   2079     }
   2080     startBuf++;
   2081   }
   2082   return false;
   2083 }
   2084 
   2085 static void scanToNextArgument(const char *&argRef) {
   2086   int angle = 0;
   2087   while (*argRef != ')' && (*argRef != ',' || angle > 0)) {
   2088     if (*argRef == '<')
   2089       angle++;
   2090     else if (*argRef == '>')
   2091       angle--;
   2092     argRef++;
   2093   }
   2094   assert(angle == 0 && "scanToNextArgument - bad protocol type syntax");
   2095 }
   2096 
   2097 bool RewriteObjC::needToScanForQualifiers(QualType T) {
   2098   if (T->isObjCQualifiedIdType())
   2099     return true;
   2100   if (const PointerType *PT = T->getAs<PointerType>()) {
   2101     if (PT->getPointeeType()->isObjCQualifiedIdType())
   2102       return true;
   2103   }
   2104   if (T->isObjCObjectPointerType()) {
   2105     T = T->getPointeeType();
   2106     return T->isObjCQualifiedInterfaceType();
   2107   }
   2108   if (T->isArrayType()) {
   2109     QualType ElemTy = Context->getBaseElementType(T);
   2110     return needToScanForQualifiers(ElemTy);
   2111   }
   2112   return false;
   2113 }
   2114 
   2115 void RewriteObjC::RewriteObjCQualifiedInterfaceTypes(Expr *E) {
   2116   QualType Type = E->getType();
   2117   if (needToScanForQualifiers(Type)) {
   2118     SourceLocation Loc, EndLoc;
   2119 
   2120     if (const CStyleCastExpr *ECE = dyn_cast<CStyleCastExpr>(E)) {
   2121       Loc = ECE->getLParenLoc();
   2122       EndLoc = ECE->getRParenLoc();
   2123     } else {
   2124       Loc = E->getLocStart();
   2125       EndLoc = E->getLocEnd();
   2126     }
   2127     // This will defend against trying to rewrite synthesized expressions.
   2128     if (Loc.isInvalid() || EndLoc.isInvalid())
   2129       return;
   2130 
   2131     const char *startBuf = SM->getCharacterData(Loc);
   2132     const char *endBuf = SM->getCharacterData(EndLoc);
   2133     const char *startRef = 0, *endRef = 0;
   2134     if (scanForProtocolRefs(startBuf, endBuf, startRef, endRef)) {
   2135       // Get the locations of the startRef, endRef.
   2136       SourceLocation LessLoc = Loc.getLocWithOffset(startRef-startBuf);
   2137       SourceLocation GreaterLoc = Loc.getLocWithOffset(endRef-startBuf+1);
   2138       // Comment out the protocol references.
   2139       InsertText(LessLoc, "/*");
   2140       InsertText(GreaterLoc, "*/");
   2141     }
   2142   }
   2143 }
   2144 
   2145 void RewriteObjC::RewriteObjCQualifiedInterfaceTypes(Decl *Dcl) {
   2146   SourceLocation Loc;
   2147   QualType Type;
   2148   const FunctionProtoType *proto = 0;
   2149   if (VarDecl *VD = dyn_cast<VarDecl>(Dcl)) {
   2150     Loc = VD->getLocation();
   2151     Type = VD->getType();
   2152   }
   2153   else if (FunctionDecl *FD = dyn_cast<FunctionDecl>(Dcl)) {
   2154     Loc = FD->getLocation();
   2155     // Check for ObjC 'id' and class types that have been adorned with protocol
   2156     // information (id<p>, C<p>*). The protocol references need to be rewritten!
   2157     const FunctionType *funcType = FD->getType()->getAs<FunctionType>();
   2158     assert(funcType && "missing function type");
   2159     proto = dyn_cast<FunctionProtoType>(funcType);
   2160     if (!proto)
   2161       return;
   2162     Type = proto->getResultType();
   2163   }
   2164   else if (FieldDecl *FD = dyn_cast<FieldDecl>(Dcl)) {
   2165     Loc = FD->getLocation();
   2166     Type = FD->getType();
   2167   }
   2168   else
   2169     return;
   2170 
   2171   if (needToScanForQualifiers(Type)) {
   2172     // Since types are unique, we need to scan the buffer.
   2173 
   2174     const char *endBuf = SM->getCharacterData(Loc);
   2175     const char *startBuf = endBuf;
   2176     while (*startBuf != ';' && *startBuf != '<' && startBuf != MainFileStart)
   2177       startBuf--; // scan backward (from the decl location) for return type.
   2178     const char *startRef = 0, *endRef = 0;
   2179     if (scanForProtocolRefs(startBuf, endBuf, startRef, endRef)) {
   2180       // Get the locations of the startRef, endRef.
   2181       SourceLocation LessLoc = Loc.getLocWithOffset(startRef-endBuf);
   2182       SourceLocation GreaterLoc = Loc.getLocWithOffset(endRef-endBuf+1);
   2183       // Comment out the protocol references.
   2184       InsertText(LessLoc, "/*");
   2185       InsertText(GreaterLoc, "*/");
   2186     }
   2187   }
   2188   if (!proto)
   2189       return; // most likely, was a variable
   2190   // Now check arguments.
   2191   const char *startBuf = SM->getCharacterData(Loc);
   2192   const char *startFuncBuf = startBuf;
   2193   for (unsigned i = 0; i < proto->getNumArgs(); i++) {
   2194     if (needToScanForQualifiers(proto->getArgType(i))) {
   2195       // Since types are unique, we need to scan the buffer.
   2196 
   2197       const char *endBuf = startBuf;
   2198       // scan forward (from the decl location) for argument types.
   2199       scanToNextArgument(endBuf);
   2200       const char *startRef = 0, *endRef = 0;
   2201       if (scanForProtocolRefs(startBuf, endBuf, startRef, endRef)) {
   2202         // Get the locations of the startRef, endRef.
   2203         SourceLocation LessLoc =
   2204           Loc.getLocWithOffset(startRef-startFuncBuf);
   2205         SourceLocation GreaterLoc =
   2206           Loc.getLocWithOffset(endRef-startFuncBuf+1);
   2207         // Comment out the protocol references.
   2208         InsertText(LessLoc, "/*");
   2209         InsertText(GreaterLoc, "*/");
   2210       }
   2211       startBuf = ++endBuf;
   2212     }
   2213     else {
   2214       // If the function name is derived from a macro expansion, then the
   2215       // argument buffer will not follow the name. Need to speak with Chris.
   2216       while (*startBuf && *startBuf != ')' && *startBuf != ',')
   2217         startBuf++; // scan forward (from the decl location) for argument types.
   2218       startBuf++;
   2219     }
   2220   }
   2221 }
   2222 
   2223 void RewriteObjC::RewriteTypeOfDecl(VarDecl *ND) {
   2224   QualType QT = ND->getType();
   2225   const Type* TypePtr = QT->getAs<Type>();
   2226   if (!isa<TypeOfExprType>(TypePtr))
   2227     return;
   2228   while (isa<TypeOfExprType>(TypePtr)) {
   2229     const TypeOfExprType *TypeOfExprTypePtr = cast<TypeOfExprType>(TypePtr);
   2230     QT = TypeOfExprTypePtr->getUnderlyingExpr()->getType();
   2231     TypePtr = QT->getAs<Type>();
   2232   }
   2233   // FIXME. This will not work for multiple declarators; as in:
   2234   // __typeof__(a) b,c,d;
   2235   std::string TypeAsString(QT.getAsString(Context->getPrintingPolicy()));
   2236   SourceLocation DeclLoc = ND->getTypeSpecStartLoc();
   2237   const char *startBuf = SM->getCharacterData(DeclLoc);
   2238   if (ND->getInit()) {
   2239     std::string Name(ND->getNameAsString());
   2240     TypeAsString += " " + Name + " = ";
   2241     Expr *E = ND->getInit();
   2242     SourceLocation startLoc;
   2243     if (const CStyleCastExpr *ECE = dyn_cast<CStyleCastExpr>(E))
   2244       startLoc = ECE->getLParenLoc();
   2245     else
   2246       startLoc = E->getLocStart();
   2247     startLoc = SM->getExpansionLoc(startLoc);
   2248     const char *endBuf = SM->getCharacterData(startLoc);
   2249     ReplaceText(DeclLoc, endBuf-startBuf-1, TypeAsString);
   2250   }
   2251   else {
   2252     SourceLocation X = ND->getLocEnd();
   2253     X = SM->getExpansionLoc(X);
   2254     const char *endBuf = SM->getCharacterData(X);
   2255     ReplaceText(DeclLoc, endBuf-startBuf-1, TypeAsString);
   2256   }
   2257 }
   2258 
   2259 // SynthSelGetUidFunctionDecl - SEL sel_registerName(const char *str);
   2260 void RewriteObjC::SynthSelGetUidFunctionDecl() {
   2261   IdentifierInfo *SelGetUidIdent = &Context->Idents.get("sel_registerName");
   2262   SmallVector<QualType, 16> ArgTys;
   2263   ArgTys.push_back(Context->getPointerType(Context->CharTy.withConst()));
   2264   QualType getFuncType =
   2265     getSimpleFunctionType(Context->getObjCSelType(), ArgTys);
   2266   SelGetUidFunctionDecl = FunctionDecl::Create(*Context, TUDecl,
   2267                                                SourceLocation(),
   2268                                                SourceLocation(),
   2269                                                SelGetUidIdent, getFuncType, 0,
   2270                                                SC_Extern);
   2271 }
   2272 
   2273 void RewriteObjC::RewriteFunctionDecl(FunctionDecl *FD) {
   2274   // declared in <objc/objc.h>
   2275   if (FD->getIdentifier() &&
   2276       FD->getName() == "sel_registerName") {
   2277     SelGetUidFunctionDecl = FD;
   2278     return;
   2279   }
   2280   RewriteObjCQualifiedInterfaceTypes(FD);
   2281 }
   2282 
   2283 void RewriteObjC::RewriteBlockPointerType(std::string& Str, QualType Type) {
   2284   std::string TypeString(Type.getAsString(Context->getPrintingPolicy()));
   2285   const char *argPtr = TypeString.c_str();
   2286   if (!strchr(argPtr, '^')) {
   2287     Str += TypeString;
   2288     return;
   2289   }
   2290   while (*argPtr) {
   2291     Str += (*argPtr == '^' ? '*' : *argPtr);
   2292     argPtr++;
   2293   }
   2294 }
   2295 
   2296 // FIXME. Consolidate this routine with RewriteBlockPointerType.
   2297 void RewriteObjC::RewriteBlockPointerTypeVariable(std::string& Str,
   2298                                                   ValueDecl *VD) {
   2299   QualType Type = VD->getType();
   2300   std::string TypeString(Type.getAsString(Context->getPrintingPolicy()));
   2301   const char *argPtr = TypeString.c_str();
   2302   int paren = 0;
   2303   while (*argPtr) {
   2304     switch (*argPtr) {
   2305       case '(':
   2306         Str += *argPtr;
   2307         paren++;
   2308         break;
   2309       case ')':
   2310         Str += *argPtr;
   2311         paren--;
   2312         break;
   2313       case '^':
   2314         Str += '*';
   2315         if (paren == 1)
   2316           Str += VD->getNameAsString();
   2317         break;
   2318       default:
   2319         Str += *argPtr;
   2320         break;
   2321     }
   2322     argPtr++;
   2323   }
   2324 }
   2325 
   2326 
   2327 void RewriteObjC::RewriteBlockLiteralFunctionDecl(FunctionDecl *FD) {
   2328   SourceLocation FunLocStart = FD->getTypeSpecStartLoc();
   2329   const FunctionType *funcType = FD->getType()->getAs<FunctionType>();
   2330   const FunctionProtoType *proto = dyn_cast<FunctionProtoType>(funcType);
   2331   if (!proto)
   2332     return;
   2333   QualType Type = proto->getResultType();
   2334   std::string FdStr = Type.getAsString(Context->getPrintingPolicy());
   2335   FdStr += " ";
   2336   FdStr += FD->getName();
   2337   FdStr +=  "(";
   2338   unsigned numArgs = proto->getNumArgs();
   2339   for (unsigned i = 0; i < numArgs; i++) {
   2340     QualType ArgType = proto->getArgType(i);
   2341     RewriteBlockPointerType(FdStr, ArgType);
   2342     if (i+1 < numArgs)
   2343       FdStr += ", ";
   2344   }
   2345   FdStr +=  ");\n";
   2346   InsertText(FunLocStart, FdStr);
   2347   CurFunctionDeclToDeclareForBlock = 0;
   2348 }
   2349 
   2350 // SynthSuperContructorFunctionDecl - id objc_super(id obj, id super);
   2351 void RewriteObjC::SynthSuperContructorFunctionDecl() {
   2352   if (SuperContructorFunctionDecl)
   2353     return;
   2354   IdentifierInfo *msgSendIdent = &Context->Idents.get("__rw_objc_super");
   2355   SmallVector<QualType, 16> ArgTys;
   2356   QualType argT = Context->getObjCIdType();
   2357   assert(!argT.isNull() && "Can't find 'id' type");
   2358   ArgTys.push_back(argT);
   2359   ArgTys.push_back(argT);
   2360   QualType msgSendType = getSimpleFunctionType(Context->getObjCIdType(),
   2361                                                ArgTys);
   2362   SuperContructorFunctionDecl = FunctionDecl::Create(*Context, TUDecl,
   2363                                                      SourceLocation(),
   2364                                                      SourceLocation(),
   2365                                                      msgSendIdent, msgSendType,
   2366                                                      0, SC_Extern);
   2367 }
   2368 
   2369 // SynthMsgSendFunctionDecl - id objc_msgSend(id self, SEL op, ...);
   2370 void RewriteObjC::SynthMsgSendFunctionDecl() {
   2371   IdentifierInfo *msgSendIdent = &Context->Idents.get("objc_msgSend");
   2372   SmallVector<QualType, 16> ArgTys;
   2373   QualType argT = Context->getObjCIdType();
   2374   assert(!argT.isNull() && "Can't find 'id' type");
   2375   ArgTys.push_back(argT);
   2376   argT = Context->getObjCSelType();
   2377   assert(!argT.isNull() && "Can't find 'SEL' type");
   2378   ArgTys.push_back(argT);
   2379   QualType msgSendType = getSimpleFunctionType(Context->getObjCIdType(),
   2380                                                ArgTys, /*isVariadic=*/true);
   2381   MsgSendFunctionDecl = FunctionDecl::Create(*Context, TUDecl,
   2382                                              SourceLocation(),
   2383                                              SourceLocation(),
   2384                                              msgSendIdent, msgSendType, 0,
   2385                                              SC_Extern);
   2386 }
   2387 
   2388 // SynthMsgSendSuperFunctionDecl - id objc_msgSendSuper(struct objc_super *, SEL op, ...);
   2389 void RewriteObjC::SynthMsgSendSuperFunctionDecl() {
   2390   IdentifierInfo *msgSendIdent = &Context->Idents.get("objc_msgSendSuper");
   2391   SmallVector<QualType, 16> ArgTys;
   2392   RecordDecl *RD = RecordDecl::Create(*Context, TTK_Struct, TUDecl,
   2393                                       SourceLocation(), SourceLocation(),
   2394                                       &Context->Idents.get("objc_super"));
   2395   QualType argT = Context->getPointerType(Context->getTagDeclType(RD));
   2396   assert(!argT.isNull() && "Can't build 'struct objc_super *' type");
   2397   ArgTys.push_back(argT);
   2398   argT = Context->getObjCSelType();
   2399   assert(!argT.isNull() && "Can't find 'SEL' type");
   2400   ArgTys.push_back(argT);
   2401   QualType msgSendType = getSimpleFunctionType(Context->getObjCIdType(),
   2402                                                ArgTys, /*isVariadic=*/true);
   2403   MsgSendSuperFunctionDecl = FunctionDecl::Create(*Context, TUDecl,
   2404                                                   SourceLocation(),
   2405                                                   SourceLocation(),
   2406                                                   msgSendIdent, msgSendType, 0,
   2407                                                   SC_Extern);
   2408 }
   2409 
   2410 // SynthMsgSendStretFunctionDecl - id objc_msgSend_stret(id self, SEL op, ...);
   2411 void RewriteObjC::SynthMsgSendStretFunctionDecl() {
   2412   IdentifierInfo *msgSendIdent = &Context->Idents.get("objc_msgSend_stret");
   2413   SmallVector<QualType, 16> ArgTys;
   2414   QualType argT = Context->getObjCIdType();
   2415   assert(!argT.isNull() && "Can't find 'id' type");
   2416   ArgTys.push_back(argT);
   2417   argT = Context->getObjCSelType();
   2418   assert(!argT.isNull() && "Can't find 'SEL' type");
   2419   ArgTys.push_back(argT);
   2420   QualType msgSendType = getSimpleFunctionType(Context->getObjCIdType(),
   2421                                                ArgTys, /*isVariadic=*/true);
   2422   MsgSendStretFunctionDecl = FunctionDecl::Create(*Context, TUDecl,
   2423                                                   SourceLocation(),
   2424                                                   SourceLocation(),
   2425                                                   msgSendIdent, msgSendType, 0,
   2426                                                   SC_Extern);
   2427 }
   2428 
   2429 // SynthMsgSendSuperStretFunctionDecl -
   2430 // id objc_msgSendSuper_stret(struct objc_super *, SEL op, ...);
   2431 void RewriteObjC::SynthMsgSendSuperStretFunctionDecl() {
   2432   IdentifierInfo *msgSendIdent =
   2433     &Context->Idents.get("objc_msgSendSuper_stret");
   2434   SmallVector<QualType, 16> ArgTys;
   2435   RecordDecl *RD = RecordDecl::Create(*Context, TTK_Struct, TUDecl,
   2436                                       SourceLocation(), SourceLocation(),
   2437                                       &Context->Idents.get("objc_super"));
   2438   QualType argT = Context->getPointerType(Context->getTagDeclType(RD));
   2439   assert(!argT.isNull() && "Can't build 'struct objc_super *' type");
   2440   ArgTys.push_back(argT);
   2441   argT = Context->getObjCSelType();
   2442   assert(!argT.isNull() && "Can't find 'SEL' type");
   2443   ArgTys.push_back(argT);
   2444   QualType msgSendType = getSimpleFunctionType(Context->getObjCIdType(),
   2445                                                ArgTys, /*isVariadic=*/true);
   2446   MsgSendSuperStretFunctionDecl = FunctionDecl::Create(*Context, TUDecl,
   2447                                                        SourceLocation(),
   2448                                                        SourceLocation(),
   2449                                                        msgSendIdent,
   2450                                                        msgSendType, 0,
   2451                                                        SC_Extern);
   2452 }
   2453 
   2454 // SynthMsgSendFpretFunctionDecl - double objc_msgSend_fpret(id self, SEL op, ...);
   2455 void RewriteObjC::SynthMsgSendFpretFunctionDecl() {
   2456   IdentifierInfo *msgSendIdent = &Context->Idents.get("objc_msgSend_fpret");
   2457   SmallVector<QualType, 16> ArgTys;
   2458   QualType argT = Context->getObjCIdType();
   2459   assert(!argT.isNull() && "Can't find 'id' type");
   2460   ArgTys.push_back(argT);
   2461   argT = Context->getObjCSelType();
   2462   assert(!argT.isNull() && "Can't find 'SEL' type");
   2463   ArgTys.push_back(argT);
   2464   QualType msgSendType = getSimpleFunctionType(Context->DoubleTy,
   2465                                                ArgTys, /*isVariadic=*/true);
   2466   MsgSendFpretFunctionDecl = FunctionDecl::Create(*Context, TUDecl,
   2467                                                   SourceLocation(),
   2468                                                   SourceLocation(),
   2469                                                   msgSendIdent, msgSendType, 0,
   2470                                                   SC_Extern);
   2471 }
   2472 
   2473 // SynthGetClassFunctionDecl - id objc_getClass(const char *name);
   2474 void RewriteObjC::SynthGetClassFunctionDecl() {
   2475   IdentifierInfo *getClassIdent = &Context->Idents.get("objc_getClass");
   2476   SmallVector<QualType, 16> ArgTys;
   2477   ArgTys.push_back(Context->getPointerType(Context->CharTy.withConst()));
   2478   QualType getClassType = getSimpleFunctionType(Context->getObjCIdType(),
   2479                                                 ArgTys);
   2480   GetClassFunctionDecl = FunctionDecl::Create(*Context, TUDecl,
   2481                                               SourceLocation(),
   2482                                               SourceLocation(),
   2483                                               getClassIdent, getClassType, 0,
   2484                                               SC_Extern);
   2485 }
   2486 
   2487 // SynthGetSuperClassFunctionDecl - Class class_getSuperclass(Class cls);
   2488 void RewriteObjC::SynthGetSuperClassFunctionDecl() {
   2489   IdentifierInfo *getSuperClassIdent =
   2490     &Context->Idents.get("class_getSuperclass");
   2491   SmallVector<QualType, 16> ArgTys;
   2492   ArgTys.push_back(Context->getObjCClassType());
   2493   QualType getClassType = getSimpleFunctionType(Context->getObjCClassType(),
   2494                                                 ArgTys);
   2495   GetSuperClassFunctionDecl = FunctionDecl::Create(*Context, TUDecl,
   2496                                                    SourceLocation(),
   2497                                                    SourceLocation(),
   2498                                                    getSuperClassIdent,
   2499                                                    getClassType, 0,
   2500                                                    SC_Extern);
   2501 }
   2502 
   2503 // SynthGetMetaClassFunctionDecl - id objc_getMetaClass(const char *name);
   2504 void RewriteObjC::SynthGetMetaClassFunctionDecl() {
   2505   IdentifierInfo *getClassIdent = &Context->Idents.get("objc_getMetaClass");
   2506   SmallVector<QualType, 16> ArgTys;
   2507   ArgTys.push_back(Context->getPointerType(Context->CharTy.withConst()));
   2508   QualType getClassType = getSimpleFunctionType(Context->getObjCIdType(),
   2509                                                 ArgTys);
   2510   GetMetaClassFunctionDecl = FunctionDecl::Create(*Context, TUDecl,
   2511                                                   SourceLocation(),
   2512                                                   SourceLocation(),
   2513                                                   getClassIdent, getClassType,
   2514                                                   0, SC_Extern);
   2515 }
   2516 
   2517 Stmt *RewriteObjC::RewriteObjCStringLiteral(ObjCStringLiteral *Exp) {
   2518   QualType strType = getConstantStringStructType();
   2519 
   2520   std::string S = "__NSConstantStringImpl_";
   2521 
   2522   std::string tmpName = InFileName;
   2523   unsigned i;
   2524   for (i=0; i < tmpName.length(); i++) {
   2525     char c = tmpName.at(i);
   2526     // replace any non alphanumeric characters with '_'.
   2527     if (!isAlphanumeric(c))
   2528       tmpName[i] = '_';
   2529   }
   2530   S += tmpName;
   2531   S += "_";
   2532   S += utostr(NumObjCStringLiterals++);
   2533 
   2534   Preamble += "static __NSConstantStringImpl " + S;
   2535   Preamble += " __attribute__ ((section (\"__DATA, __cfstring\"))) = {__CFConstantStringClassReference,";
   2536   Preamble += "0x000007c8,"; // utf8_str
   2537   // The pretty printer for StringLiteral handles escape characters properly.
   2538   std::string prettyBufS;
   2539   llvm::raw_string_ostream prettyBuf(prettyBufS);
   2540   Exp->getString()->printPretty(prettyBuf, 0, PrintingPolicy(LangOpts));
   2541   Preamble += prettyBuf.str();
   2542   Preamble += ",";
   2543   Preamble += utostr(Exp->getString()->getByteLength()) + "};\n";
   2544 
   2545   VarDecl *NewVD = VarDecl::Create(*Context, TUDecl, SourceLocation(),
   2546                                    SourceLocation(), &Context->Idents.get(S),
   2547                                    strType, 0, SC_Static);
   2548   DeclRefExpr *DRE = new (Context) DeclRefExpr(NewVD, false, strType, VK_LValue,
   2549                                                SourceLocation());
   2550   Expr *Unop = new (Context) UnaryOperator(DRE, UO_AddrOf,
   2551                                  Context->getPointerType(DRE->getType()),
   2552                                            VK_RValue, OK_Ordinary,
   2553                                            SourceLocation());
   2554   // cast to NSConstantString *
   2555   CastExpr *cast = NoTypeInfoCStyleCastExpr(Context, Exp->getType(),
   2556                                             CK_CPointerToObjCPointerCast, Unop);
   2557   ReplaceStmt(Exp, cast);
   2558   // delete Exp; leak for now, see RewritePropertyOrImplicitSetter() usage for more info.
   2559   return cast;
   2560 }
   2561 
   2562 // struct objc_super { struct objc_object *receiver; struct objc_class *super; };
   2563 QualType RewriteObjC::getSuperStructType() {
   2564   if (!SuperStructDecl) {
   2565     SuperStructDecl = RecordDecl::Create(*Context, TTK_Struct, TUDecl,
   2566                                          SourceLocation(), SourceLocation(),
   2567                                          &Context->Idents.get("objc_super"));
   2568     QualType FieldTypes[2];
   2569 
   2570     // struct objc_object *receiver;
   2571     FieldTypes[0] = Context->getObjCIdType();
   2572     // struct objc_class *super;
   2573     FieldTypes[1] = Context->getObjCClassType();
   2574 
   2575     // Create fields
   2576     for (unsigned i = 0; i < 2; ++i) {
   2577       SuperStructDecl->addDecl(FieldDecl::Create(*Context, SuperStructDecl,
   2578                                                  SourceLocation(),
   2579                                                  SourceLocation(), 0,
   2580                                                  FieldTypes[i], 0,
   2581                                                  /*BitWidth=*/0,
   2582                                                  /*Mutable=*/false,
   2583                                                  ICIS_NoInit));
   2584     }
   2585 
   2586     SuperStructDecl->completeDefinition();
   2587   }
   2588   return Context->getTagDeclType(SuperStructDecl);
   2589 }
   2590 
   2591 QualType RewriteObjC::getConstantStringStructType() {
   2592   if (!ConstantStringDecl) {
   2593     ConstantStringDecl = RecordDecl::Create(*Context, TTK_Struct, TUDecl,
   2594                                             SourceLocation(), SourceLocation(),
   2595                          &Context->Idents.get("__NSConstantStringImpl"));
   2596     QualType FieldTypes[4];
   2597 
   2598     // struct objc_object *receiver;
   2599     FieldTypes[0] = Context->getObjCIdType();
   2600     // int flags;
   2601     FieldTypes[1] = Context->IntTy;
   2602     // char *str;
   2603     FieldTypes[2] = Context->getPointerType(Context->CharTy);
   2604     // long length;
   2605     FieldTypes[3] = Context->LongTy;
   2606 
   2607     // Create fields
   2608     for (unsigned i = 0; i < 4; ++i) {
   2609       ConstantStringDecl->addDecl(FieldDecl::Create(*Context,
   2610                                                     ConstantStringDecl,
   2611                                                     SourceLocation(),
   2612                                                     SourceLocation(), 0,
   2613                                                     FieldTypes[i], 0,
   2614                                                     /*BitWidth=*/0,
   2615                                                     /*Mutable=*/true,
   2616                                                     ICIS_NoInit));
   2617     }
   2618 
   2619     ConstantStringDecl->completeDefinition();
   2620   }
   2621   return Context->getTagDeclType(ConstantStringDecl);
   2622 }
   2623 
   2624 CallExpr *RewriteObjC::SynthMsgSendStretCallExpr(FunctionDecl *MsgSendStretFlavor,
   2625                                                 QualType msgSendType,
   2626                                                 QualType returnType,
   2627                                                 SmallVectorImpl<QualType> &ArgTypes,
   2628                                                 SmallVectorImpl<Expr*> &MsgExprs,
   2629                                                 ObjCMethodDecl *Method) {
   2630   // Create a reference to the objc_msgSend_stret() declaration.
   2631   DeclRefExpr *STDRE = new (Context) DeclRefExpr(MsgSendStretFlavor,
   2632                                                  false, msgSendType,
   2633                                                  VK_LValue, SourceLocation());
   2634   // Need to cast objc_msgSend_stret to "void *" (see above comment).
   2635   CastExpr *cast = NoTypeInfoCStyleCastExpr(Context,
   2636                                   Context->getPointerType(Context->VoidTy),
   2637                                   CK_BitCast, STDRE);
   2638   // Now do the "normal" pointer to function cast.
   2639   QualType castType = getSimpleFunctionType(returnType, ArgTypes,
   2640                                             Method ? Method->isVariadic()
   2641                                                    : false);
   2642   castType = Context->getPointerType(castType);
   2643   cast = NoTypeInfoCStyleCastExpr(Context, castType, CK_BitCast,
   2644                                             cast);
   2645 
   2646   // Don't forget the parens to enforce the proper binding.
   2647   ParenExpr *PE = new (Context) ParenExpr(SourceLocation(), SourceLocation(), cast);
   2648 
   2649   const FunctionType *FT = msgSendType->getAs<FunctionType>();
   2650   CallExpr *STCE = new (Context) CallExpr(*Context, PE, MsgExprs,
   2651                                           FT->getResultType(), VK_RValue,
   2652                                           SourceLocation());
   2653   return STCE;
   2654 
   2655 }
   2656 
   2657 
   2658 Stmt *RewriteObjC::SynthMessageExpr(ObjCMessageExpr *Exp,
   2659                                     SourceLocation StartLoc,
   2660                                     SourceLocation EndLoc) {
   2661   if (!SelGetUidFunctionDecl)
   2662     SynthSelGetUidFunctionDecl();
   2663   if (!MsgSendFunctionDecl)
   2664     SynthMsgSendFunctionDecl();
   2665   if (!MsgSendSuperFunctionDecl)
   2666     SynthMsgSendSuperFunctionDecl();
   2667   if (!MsgSendStretFunctionDecl)
   2668     SynthMsgSendStretFunctionDecl();
   2669   if (!MsgSendSuperStretFunctionDecl)
   2670     SynthMsgSendSuperStretFunctionDecl();
   2671   if (!MsgSendFpretFunctionDecl)
   2672     SynthMsgSendFpretFunctionDecl();
   2673   if (!GetClassFunctionDecl)
   2674     SynthGetClassFunctionDecl();
   2675   if (!GetSuperClassFunctionDecl)
   2676     SynthGetSuperClassFunctionDecl();
   2677   if (!GetMetaClassFunctionDecl)
   2678     SynthGetMetaClassFunctionDecl();
   2679 
   2680   // default to objc_msgSend().
   2681   FunctionDecl *MsgSendFlavor = MsgSendFunctionDecl;
   2682   // May need to use objc_msgSend_stret() as well.
   2683   FunctionDecl *MsgSendStretFlavor = 0;
   2684   if (ObjCMethodDecl *mDecl = Exp->getMethodDecl()) {
   2685     QualType resultType = mDecl->getResultType();
   2686     if (resultType->isRecordType())
   2687       MsgSendStretFlavor = MsgSendStretFunctionDecl;
   2688     else if (resultType->isRealFloatingType())
   2689       MsgSendFlavor = MsgSendFpretFunctionDecl;
   2690   }
   2691 
   2692   // Synthesize a call to objc_msgSend().
   2693   SmallVector<Expr*, 8> MsgExprs;
   2694   switch (Exp->getReceiverKind()) {
   2695   case ObjCMessageExpr::SuperClass: {
   2696     MsgSendFlavor = MsgSendSuperFunctionDecl;
   2697     if (MsgSendStretFlavor)
   2698       MsgSendStretFlavor = MsgSendSuperStretFunctionDecl;
   2699     assert(MsgSendFlavor && "MsgSendFlavor is NULL!");
   2700 
   2701     ObjCInterfaceDecl *ClassDecl = CurMethodDef->getClassInterface();
   2702 
   2703     SmallVector<Expr*, 4> InitExprs;
   2704 
   2705     // set the receiver to self, the first argument to all methods.
   2706     InitExprs.push_back(
   2707       NoTypeInfoCStyleCastExpr(Context, Context->getObjCIdType(),
   2708                                CK_BitCast,
   2709                    new (Context) DeclRefExpr(CurMethodDef->getSelfDecl(),
   2710                                              false,
   2711                                              Context->getObjCIdType(),
   2712                                              VK_RValue,
   2713                                              SourceLocation()))
   2714                         ); // set the 'receiver'.
   2715 
   2716     // (id)class_getSuperclass((Class)objc_getClass("CurrentClass"))
   2717     SmallVector<Expr*, 8> ClsExprs;
   2718     QualType argType = Context->getPointerType(Context->CharTy);
   2719     ClsExprs.push_back(StringLiteral::Create(*Context,
   2720                                    ClassDecl->getIdentifier()->getName(),
   2721                                    StringLiteral::Ascii, false,
   2722                                    argType, SourceLocation()));
   2723     CallExpr *Cls = SynthesizeCallToFunctionDecl(GetMetaClassFunctionDecl,
   2724                                                  &ClsExprs[0],
   2725                                                  ClsExprs.size(),
   2726                                                  StartLoc,
   2727                                                  EndLoc);
   2728     // (Class)objc_getClass("CurrentClass")
   2729     CastExpr *ArgExpr = NoTypeInfoCStyleCastExpr(Context,
   2730                                              Context->getObjCClassType(),
   2731                                              CK_BitCast, Cls);
   2732     ClsExprs.clear();
   2733     ClsExprs.push_back(ArgExpr);
   2734     Cls = SynthesizeCallToFunctionDecl(GetSuperClassFunctionDecl,
   2735                                        &ClsExprs[0], ClsExprs.size(),
   2736                                        StartLoc, EndLoc);
   2737 
   2738     // (id)class_getSuperclass((Class)objc_getClass("CurrentClass"))
   2739     // To turn off a warning, type-cast to 'id'
   2740     InitExprs.push_back( // set 'super class', using class_getSuperclass().
   2741                         NoTypeInfoCStyleCastExpr(Context,
   2742                                                  Context->getObjCIdType(),
   2743                                                  CK_BitCast, Cls));
   2744     // struct objc_super
   2745     QualType superType = getSuperStructType();
   2746     Expr *SuperRep;
   2747 
   2748     if (LangOpts.MicrosoftExt) {
   2749       SynthSuperContructorFunctionDecl();
   2750       // Simulate a contructor call...
   2751       DeclRefExpr *DRE = new (Context) DeclRefExpr(SuperContructorFunctionDecl,
   2752                                                    false, superType, VK_LValue,
   2753                                                    SourceLocation());
   2754       SuperRep = new (Context) CallExpr(*Context, DRE, InitExprs,
   2755                                         superType, VK_LValue,
   2756                                         SourceLocation());
   2757       // The code for super is a little tricky to prevent collision with
   2758       // the structure definition in the header. The rewriter has it's own
   2759       // internal definition (__rw_objc_super) that is uses. This is why
   2760       // we need the cast below. For example:
   2761       // (struct objc_super *)&__rw_objc_super((id)self, (id)objc_getClass("SUPER"))
   2762       //
   2763       SuperRep = new (Context) UnaryOperator(SuperRep, UO_AddrOf,
   2764                                Context->getPointerType(SuperRep->getType()),
   2765                                              VK_RValue, OK_Ordinary,
   2766                                              SourceLocation());
   2767       SuperRep = NoTypeInfoCStyleCastExpr(Context,
   2768                                           Context->getPointerType(superType),
   2769                                           CK_BitCast, SuperRep);
   2770     } else {
   2771       // (struct objc_super) { <exprs from above> }
   2772       InitListExpr *ILE =
   2773         new (Context) InitListExpr(*Context, SourceLocation(), InitExprs,
   2774                                    SourceLocation());
   2775       TypeSourceInfo *superTInfo
   2776         = Context->getTrivialTypeSourceInfo(superType);
   2777       SuperRep = new (Context) CompoundLiteralExpr(SourceLocation(), superTInfo,
   2778                                                    superType, VK_LValue,
   2779                                                    ILE, false);
   2780       // struct objc_super *
   2781       SuperRep = new (Context) UnaryOperator(SuperRep, UO_AddrOf,
   2782                                Context->getPointerType(SuperRep->getType()),
   2783                                              VK_RValue, OK_Ordinary,
   2784                                              SourceLocation());
   2785     }
   2786     MsgExprs.push_back(SuperRep);
   2787     break;
   2788   }
   2789 
   2790   case ObjCMessageExpr::Class: {
   2791     SmallVector<Expr*, 8> ClsExprs;
   2792     QualType argType = Context->getPointerType(Context->CharTy);
   2793     ObjCInterfaceDecl *Class
   2794       = Exp->getClassReceiver()->getAs<ObjCObjectType>()->getInterface();
   2795     IdentifierInfo *clsName = Class->getIdentifier();
   2796     ClsExprs.push_back(StringLiteral::Create(*Context,
   2797                                              clsName->getName(),
   2798                                              StringLiteral::Ascii, false,
   2799                                              argType, SourceLocation()));
   2800     CallExpr *Cls = SynthesizeCallToFunctionDecl(GetClassFunctionDecl,
   2801                                                  &ClsExprs[0],
   2802                                                  ClsExprs.size(),
   2803                                                  StartLoc, EndLoc);
   2804     MsgExprs.push_back(Cls);
   2805     break;
   2806   }
   2807 
   2808   case ObjCMessageExpr::SuperInstance:{
   2809     MsgSendFlavor = MsgSendSuperFunctionDecl;
   2810     if (MsgSendStretFlavor)
   2811       MsgSendStretFlavor = MsgSendSuperStretFunctionDecl;
   2812     assert(MsgSendFlavor && "MsgSendFlavor is NULL!");
   2813     ObjCInterfaceDecl *ClassDecl = CurMethodDef->getClassInterface();
   2814     SmallVector<Expr*, 4> InitExprs;
   2815 
   2816     InitExprs.push_back(
   2817       NoTypeInfoCStyleCastExpr(Context, Context->getObjCIdType(),
   2818                                CK_BitCast,
   2819                    new (Context) DeclRefExpr(CurMethodDef->getSelfDecl(),
   2820                                              false,
   2821                                              Context->getObjCIdType(),
   2822                                              VK_RValue, SourceLocation()))
   2823                         ); // set the 'receiver'.
   2824 
   2825     // (id)class_getSuperclass((Class)objc_getClass("CurrentClass"))
   2826     SmallVector<Expr*, 8> ClsExprs;
   2827     QualType argType = Context->getPointerType(Context->CharTy);
   2828     ClsExprs.push_back(StringLiteral::Create(*Context,
   2829                                    ClassDecl->getIdentifier()->getName(),
   2830                                    StringLiteral::Ascii, false, argType,
   2831                                    SourceLocation()));
   2832     CallExpr *Cls = SynthesizeCallToFunctionDecl(GetClassFunctionDecl,
   2833                                                  &ClsExprs[0],
   2834                                                  ClsExprs.size(),
   2835                                                  StartLoc, EndLoc);
   2836     // (Class)objc_getClass("CurrentClass")
   2837     CastExpr *ArgExpr = NoTypeInfoCStyleCastExpr(Context,
   2838                                                  Context->getObjCClassType(),
   2839                                                  CK_BitCast, Cls);
   2840     ClsExprs.clear();
   2841     ClsExprs.push_back(ArgExpr);
   2842     Cls = SynthesizeCallToFunctionDecl(GetSuperClassFunctionDecl,
   2843                                        &ClsExprs[0], ClsExprs.size(),
   2844                                        StartLoc, EndLoc);
   2845 
   2846     // (id)class_getSuperclass((Class)objc_getClass("CurrentClass"))
   2847     // To turn off a warning, type-cast to 'id'
   2848     InitExprs.push_back(
   2849       // set 'super class', using class_getSuperclass().
   2850       NoTypeInfoCStyleCastExpr(Context, Context->getObjCIdType(),
   2851                                CK_BitCast, Cls));
   2852     // struct objc_super
   2853     QualType superType = getSuperStructType();
   2854     Expr *SuperRep;
   2855 
   2856     if (LangOpts.MicrosoftExt) {
   2857       SynthSuperContructorFunctionDecl();
   2858       // Simulate a contructor call...
   2859       DeclRefExpr *DRE = new (Context) DeclRefExpr(SuperContructorFunctionDecl,
   2860                                                    false, superType, VK_LValue,
   2861                                                    SourceLocation());
   2862       SuperRep = new (Context) CallExpr(*Context, DRE, InitExprs,
   2863                                         superType, VK_LValue, SourceLocation());
   2864       // The code for super is a little tricky to prevent collision with
   2865       // the structure definition in the header. The rewriter has it's own
   2866       // internal definition (__rw_objc_super) that is uses. This is why
   2867       // we need the cast below. For example:
   2868       // (struct objc_super *)&__rw_objc_super((id)self, (id)objc_getClass("SUPER"))
   2869       //
   2870       SuperRep = new (Context) UnaryOperator(SuperRep, UO_AddrOf,
   2871                                Context->getPointerType(SuperRep->getType()),
   2872                                VK_RValue, OK_Ordinary,
   2873                                SourceLocation());
   2874       SuperRep = NoTypeInfoCStyleCastExpr(Context,
   2875                                Context->getPointerType(superType),
   2876                                CK_BitCast, SuperRep);
   2877     } else {
   2878       // (struct objc_super) { <exprs from above> }
   2879       InitListExpr *ILE =
   2880         new (Context) InitListExpr(*Context, SourceLocation(), InitExprs,
   2881                                    SourceLocation());
   2882       TypeSourceInfo *superTInfo
   2883         = Context->getTrivialTypeSourceInfo(superType);
   2884       SuperRep = new (Context) CompoundLiteralExpr(SourceLocation(), superTInfo,
   2885                                                    superType, VK_RValue, ILE,
   2886                                                    false);
   2887     }
   2888     MsgExprs.push_back(SuperRep);
   2889     break;
   2890   }
   2891 
   2892   case ObjCMessageExpr::Instance: {
   2893     // Remove all type-casts because it may contain objc-style types; e.g.
   2894     // Foo<Proto> *.
   2895     Expr *recExpr = Exp->getInstanceReceiver();
   2896     while (CStyleCastExpr *CE = dyn_cast<CStyleCastExpr>(recExpr))
   2897       recExpr = CE->getSubExpr();
   2898     CastKind CK = recExpr->getType()->isObjCObjectPointerType()
   2899                     ? CK_BitCast : recExpr->getType()->isBlockPointerType()
   2900                                      ? CK_BlockPointerToObjCPointerCast
   2901                                      : CK_CPointerToObjCPointerCast;
   2902 
   2903     recExpr = NoTypeInfoCStyleCastExpr(Context, Context->getObjCIdType(),
   2904                                        CK, recExpr);
   2905     MsgExprs.push_back(recExpr);
   2906     break;
   2907   }
   2908   }
   2909 
   2910   // Create a call to sel_registerName("selName"), it will be the 2nd argument.
   2911   SmallVector<Expr*, 8> SelExprs;
   2912   QualType argType = Context->getPointerType(Context->CharTy);
   2913   SelExprs.push_back(StringLiteral::Create(*Context,
   2914                                        Exp->getSelector().getAsString(),
   2915                                        StringLiteral::Ascii, false,
   2916                                        argType, SourceLocation()));
   2917   CallExpr *SelExp = SynthesizeCallToFunctionDecl(SelGetUidFunctionDecl,
   2918                                                  &SelExprs[0], SelExprs.size(),
   2919                                                   StartLoc,
   2920                                                   EndLoc);
   2921   MsgExprs.push_back(SelExp);
   2922 
   2923   // Now push any user supplied arguments.
   2924   for (unsigned i = 0; i < Exp->getNumArgs(); i++) {
   2925     Expr *userExpr = Exp->getArg(i);
   2926     // Make all implicit casts explicit...ICE comes in handy:-)
   2927     if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(userExpr)) {
   2928       // Reuse the ICE type, it is exactly what the doctor ordered.
   2929       QualType type = ICE->getType();
   2930       if (needToScanForQualifiers(type))
   2931         type = Context->getObjCIdType();
   2932       // Make sure we convert "type (^)(...)" to "type (*)(...)".
   2933       (void)convertBlockPointerToFunctionPointer(type);
   2934       const Expr *SubExpr = ICE->IgnoreParenImpCasts();
   2935       CastKind CK;
   2936       if (SubExpr->getType()->isIntegralType(*Context) &&
   2937           type->isBooleanType()) {
   2938         CK = CK_IntegralToBoolean;
   2939       } else if (type->isObjCObjectPointerType()) {
   2940         if (SubExpr->getType()->isBlockPointerType()) {
   2941           CK = CK_BlockPointerToObjCPointerCast;
   2942         } else if (SubExpr->getType()->isPointerType()) {
   2943           CK = CK_CPointerToObjCPointerCast;
   2944         } else {
   2945           CK = CK_BitCast;
   2946         }
   2947       } else {
   2948         CK = CK_BitCast;
   2949       }
   2950 
   2951       userExpr = NoTypeInfoCStyleCastExpr(Context, type, CK, userExpr);
   2952     }
   2953     // Make id<P...> cast into an 'id' cast.
   2954     else if (CStyleCastExpr *CE = dyn_cast<CStyleCastExpr>(userExpr)) {
   2955       if (CE->getType()->isObjCQualifiedIdType()) {
   2956         while ((CE = dyn_cast<CStyleCastExpr>(userExpr)))
   2957           userExpr = CE->getSubExpr();
   2958         CastKind CK;
   2959         if (userExpr->getType()->isIntegralType(*Context)) {
   2960           CK = CK_IntegralToPointer;
   2961         } else if (userExpr->getType()->isBlockPointerType()) {
   2962           CK = CK_BlockPointerToObjCPointerCast;
   2963         } else if (userExpr->getType()->isPointerType()) {
   2964           CK = CK_CPointerToObjCPointerCast;
   2965         } else {
   2966           CK = CK_BitCast;
   2967         }
   2968         userExpr = NoTypeInfoCStyleCastExpr(Context, Context->getObjCIdType(),
   2969                                             CK, userExpr);
   2970       }
   2971     }
   2972     MsgExprs.push_back(userExpr);
   2973     // We've transferred the ownership to MsgExprs. For now, we *don't* null
   2974     // out the argument in the original expression (since we aren't deleting
   2975     // the ObjCMessageExpr). See RewritePropertyOrImplicitSetter() usage for more info.
   2976     //Exp->setArg(i, 0);
   2977   }
   2978   // Generate the funky cast.
   2979   CastExpr *cast;
   2980   SmallVector<QualType, 8> ArgTypes;
   2981   QualType returnType;
   2982 
   2983   // Push 'id' and 'SEL', the 2 implicit arguments.
   2984   if (MsgSendFlavor == MsgSendSuperFunctionDecl)
   2985     ArgTypes.push_back(Context->getPointerType(getSuperStructType()));
   2986   else
   2987     ArgTypes.push_back(Context->getObjCIdType());
   2988   ArgTypes.push_back(Context->getObjCSelType());
   2989   if (ObjCMethodDecl *OMD = Exp->getMethodDecl()) {
   2990     // Push any user argument types.
   2991     for (ObjCMethodDecl::param_iterator PI = OMD->param_begin(),
   2992          E = OMD->param_end(); PI != E; ++PI) {
   2993       QualType t = (*PI)->getType()->isObjCQualifiedIdType()
   2994                      ? Context->getObjCIdType()
   2995                      : (*PI)->getType();
   2996       // Make sure we convert "t (^)(...)" to "t (*)(...)".
   2997       (void)convertBlockPointerToFunctionPointer(t);
   2998       ArgTypes.push_back(t);
   2999     }
   3000     returnType = Exp->getType();
   3001     convertToUnqualifiedObjCType(returnType);
   3002     (void)convertBlockPointerToFunctionPointer(returnType);
   3003   } else {
   3004     returnType = Context->getObjCIdType();
   3005   }
   3006   // Get the type, we will need to reference it in a couple spots.
   3007   QualType msgSendType = MsgSendFlavor->getType();
   3008 
   3009   // Create a reference to the objc_msgSend() declaration.
   3010   DeclRefExpr *DRE = new (Context) DeclRefExpr(MsgSendFlavor, false, msgSendType,
   3011                                                VK_LValue, SourceLocation());
   3012 
   3013   // Need to cast objc_msgSend to "void *" (to workaround a GCC bandaid).
   3014   // If we don't do this cast, we get the following bizarre warning/note:
   3015   // xx.m:13: warning: function called through a non-compatible type
   3016   // xx.m:13: note: if this code is reached, the program will abort
   3017   cast = NoTypeInfoCStyleCastExpr(Context,
   3018                                   Context->getPointerType(Context->VoidTy),
   3019                                   CK_BitCast, DRE);
   3020 
   3021   // Now do the "normal" pointer to function cast.
   3022   // If we don't have a method decl, force a variadic cast.
   3023   const ObjCMethodDecl *MD = Exp->getMethodDecl();
   3024   QualType castType =
   3025     getSimpleFunctionType(returnType, ArgTypes, MD ? MD->isVariadic() : true);
   3026   castType = Context->getPointerType(castType);
   3027   cast = NoTypeInfoCStyleCastExpr(Context, castType, CK_BitCast,
   3028                                   cast);
   3029 
   3030   // Don't forget the parens to enforce the proper binding.
   3031   ParenExpr *PE = new (Context) ParenExpr(StartLoc, EndLoc, cast);
   3032 
   3033   const FunctionType *FT = msgSendType->getAs<FunctionType>();
   3034   CallExpr *CE = new (Context) CallExpr(*Context, PE, MsgExprs,
   3035                                         FT->getResultType(), VK_RValue,
   3036                                         EndLoc);
   3037   Stmt *ReplacingStmt = CE;
   3038   if (MsgSendStretFlavor) {
   3039     // We have the method which returns a struct/union. Must also generate
   3040     // call to objc_msgSend_stret and hang both varieties on a conditional
   3041     // expression which dictate which one to envoke depending on size of
   3042     // method's return type.
   3043 
   3044     CallExpr *STCE = SynthMsgSendStretCallExpr(MsgSendStretFlavor,
   3045                                                msgSendType, returnType,
   3046                                                ArgTypes, MsgExprs,
   3047                                                Exp->getMethodDecl());
   3048 
   3049     // Build sizeof(returnType)
   3050     UnaryExprOrTypeTraitExpr *sizeofExpr =
   3051        new (Context) UnaryExprOrTypeTraitExpr(UETT_SizeOf,
   3052                                  Context->getTrivialTypeSourceInfo(returnType),
   3053                                  Context->getSizeType(), SourceLocation(),
   3054                                  SourceLocation());
   3055     // (sizeof(returnType) <= 8 ? objc_msgSend(...) : objc_msgSend_stret(...))
   3056     // FIXME: Value of 8 is base on ppc32/x86 ABI for the most common cases.
   3057     // For X86 it is more complicated and some kind of target specific routine
   3058     // is needed to decide what to do.
   3059     unsigned IntSize =
   3060       static_cast<unsigned>(Context->getTypeSize(Context->IntTy));
   3061     IntegerLiteral *limit = IntegerLiteral::Create(*Context,
   3062                                                    llvm::APInt(IntSize, 8),
   3063                                                    Context->IntTy,
   3064                                                    SourceLocation());
   3065     BinaryOperator *lessThanExpr =
   3066       new (Context) BinaryOperator(sizeofExpr, limit, BO_LE, Context->IntTy,
   3067                                    VK_RValue, OK_Ordinary, SourceLocation(),
   3068                                    false);
   3069     // (sizeof(returnType) <= 8 ? objc_msgSend(...) : objc_msgSend_stret(...))
   3070     ConditionalOperator *CondExpr =
   3071       new (Context) ConditionalOperator(lessThanExpr,
   3072                                         SourceLocation(), CE,
   3073                                         SourceLocation(), STCE,
   3074                                         returnType, VK_RValue, OK_Ordinary);
   3075     ReplacingStmt = new (Context) ParenExpr(SourceLocation(), SourceLocation(),
   3076                                             CondExpr);
   3077   }
   3078   // delete Exp; leak for now, see RewritePropertyOrImplicitSetter() usage for more info.
   3079   return ReplacingStmt;
   3080 }
   3081 
   3082 Stmt *RewriteObjC::RewriteMessageExpr(ObjCMessageExpr *Exp) {
   3083   Stmt *ReplacingStmt = SynthMessageExpr(Exp, Exp->getLocStart(),
   3084                                          Exp->getLocEnd());
   3085 
   3086   // Now do the actual rewrite.
   3087   ReplaceStmt(Exp, ReplacingStmt);
   3088 
   3089   // delete Exp; leak for now, see RewritePropertyOrImplicitSetter() usage for more info.
   3090   return ReplacingStmt;
   3091 }
   3092 
   3093 // typedef struct objc_object Protocol;
   3094 QualType RewriteObjC::getProtocolType() {
   3095   if (!ProtocolTypeDecl) {
   3096     TypeSourceInfo *TInfo
   3097       = Context->getTrivialTypeSourceInfo(Context->getObjCIdType());
   3098     ProtocolTypeDecl = TypedefDecl::Create(*Context, TUDecl,
   3099                                            SourceLocation(), SourceLocation(),
   3100                                            &Context->Idents.get("Protocol"),
   3101                                            TInfo);
   3102   }
   3103   return Context->getTypeDeclType(ProtocolTypeDecl);
   3104 }
   3105 
   3106 /// RewriteObjCProtocolExpr - Rewrite a protocol expression into
   3107 /// a synthesized/forward data reference (to the protocol's metadata).
   3108 /// The forward references (and metadata) are generated in
   3109 /// RewriteObjC::HandleTranslationUnit().
   3110 Stmt *RewriteObjC::RewriteObjCProtocolExpr(ObjCProtocolExpr *Exp) {
   3111   std::string Name = "_OBJC_PROTOCOL_" + Exp->getProtocol()->getNameAsString();
   3112   IdentifierInfo *ID = &Context->Idents.get(Name);
   3113   VarDecl *VD = VarDecl::Create(*Context, TUDecl, SourceLocation(),
   3114                                 SourceLocation(), ID, getProtocolType(), 0,
   3115                                 SC_Extern);
   3116   DeclRefExpr *DRE = new (Context) DeclRefExpr(VD, false, getProtocolType(),
   3117                                                VK_LValue, SourceLocation());
   3118   Expr *DerefExpr = new (Context) UnaryOperator(DRE, UO_AddrOf,
   3119                              Context->getPointerType(DRE->getType()),
   3120                              VK_RValue, OK_Ordinary, SourceLocation());
   3121   CastExpr *castExpr = NoTypeInfoCStyleCastExpr(Context, DerefExpr->getType(),
   3122                                                 CK_BitCast,
   3123                                                 DerefExpr);
   3124   ReplaceStmt(Exp, castExpr);
   3125   ProtocolExprDecls.insert(Exp->getProtocol()->getCanonicalDecl());
   3126   // delete Exp; leak for now, see RewritePropertyOrImplicitSetter() usage for more info.
   3127   return castExpr;
   3128 
   3129 }
   3130 
   3131 bool RewriteObjC::BufferContainsPPDirectives(const char *startBuf,
   3132                                              const char *endBuf) {
   3133   while (startBuf < endBuf) {
   3134     if (*startBuf == '#') {
   3135       // Skip whitespace.
   3136       for (++startBuf; startBuf[0] == ' ' || startBuf[0] == '\t'; ++startBuf)
   3137         ;
   3138       if (!strncmp(startBuf, "if", strlen("if")) ||
   3139           !strncmp(startBuf, "ifdef", strlen("ifdef")) ||
   3140           !strncmp(startBuf, "ifndef", strlen("ifndef")) ||
   3141           !strncmp(startBuf, "define", strlen("define")) ||
   3142           !strncmp(startBuf, "undef", strlen("undef")) ||
   3143           !strncmp(startBuf, "else", strlen("else")) ||
   3144           !strncmp(startBuf, "elif", strlen("elif")) ||
   3145           !strncmp(startBuf, "endif", strlen("endif")) ||
   3146           !strncmp(startBuf, "pragma", strlen("pragma")) ||
   3147           !strncmp(startBuf, "include", strlen("include")) ||
   3148           !strncmp(startBuf, "import", strlen("import")) ||
   3149           !strncmp(startBuf, "include_next", strlen("include_next")))
   3150         return true;
   3151     }
   3152     startBuf++;
   3153   }
   3154   return false;
   3155 }
   3156 
   3157 /// RewriteObjCInternalStruct - Rewrite one internal struct corresponding to
   3158 /// an objective-c class with ivars.
   3159 void RewriteObjC::RewriteObjCInternalStruct(ObjCInterfaceDecl *CDecl,
   3160                                                std::string &Result) {
   3161   assert(CDecl && "Class missing in SynthesizeObjCInternalStruct");
   3162   assert(CDecl->getName() != "" &&
   3163          "Name missing in SynthesizeObjCInternalStruct");
   3164   // Do not synthesize more than once.
   3165   if (ObjCSynthesizedStructs.count(CDecl))
   3166     return;
   3167   ObjCInterfaceDecl *RCDecl = CDecl->getSuperClass();
   3168   int NumIvars = CDecl->ivar_size();
   3169   SourceLocation LocStart = CDecl->getLocStart();
   3170   SourceLocation LocEnd = CDecl->getEndOfDefinitionLoc();
   3171 
   3172   const char *startBuf = SM->getCharacterData(LocStart);
   3173   const char *endBuf = SM->getCharacterData(LocEnd);
   3174 
   3175   // If no ivars and no root or if its root, directly or indirectly,
   3176   // have no ivars (thus not synthesized) then no need to synthesize this class.
   3177   if ((!CDecl->isThisDeclarationADefinition() || NumIvars == 0) &&
   3178       (!RCDecl || !ObjCSynthesizedStructs.count(RCDecl))) {
   3179     endBuf += Lexer::MeasureTokenLength(LocEnd, *SM, LangOpts);
   3180     ReplaceText(LocStart, endBuf-startBuf, Result);
   3181     return;
   3182   }
   3183 
   3184   // FIXME: This has potential of causing problem. If
   3185   // SynthesizeObjCInternalStruct is ever called recursively.
   3186   Result += "\nstruct ";
   3187   Result += CDecl->getNameAsString();
   3188   if (LangOpts.MicrosoftExt)
   3189     Result += "_IMPL";
   3190 
   3191   if (NumIvars > 0) {
   3192     const char *cursor = strchr(startBuf, '{');
   3193     assert((cursor && endBuf)
   3194            && "SynthesizeObjCInternalStruct - malformed @interface");
   3195     // If the buffer contains preprocessor directives, we do more fine-grained
   3196     // rewrites. This is intended to fix code that looks like (which occurs in
   3197     // NSURL.h, for example):
   3198     //
   3199     // #ifdef XYZ
   3200     // @interface Foo : NSObject
   3201     // #else
   3202     // @interface FooBar : NSObject
   3203     // #endif
   3204     // {
   3205     //    int i;
   3206     // }
   3207     // @end
   3208     //
   3209     // This clause is segregated to avoid breaking the common case.
   3210     if (BufferContainsPPDirectives(startBuf, cursor)) {
   3211       SourceLocation L = RCDecl ? CDecl->getSuperClassLoc() :
   3212                                   CDecl->getAtStartLoc();
   3213       const char *endHeader = SM->getCharacterData(L);
   3214       endHeader += Lexer::MeasureTokenLength(L, *SM, LangOpts);
   3215 
   3216       if (CDecl->protocol_begin() != CDecl->protocol_end()) {
   3217         // advance to the end of the referenced protocols.
   3218         while (endHeader < cursor && *endHeader != '>') endHeader++;
   3219         endHeader++;
   3220       }
   3221       // rewrite the original header
   3222       ReplaceText(LocStart, endHeader-startBuf, Result);
   3223     } else {
   3224       // rewrite the original header *without* disturbing the '{'
   3225       ReplaceText(LocStart, cursor-startBuf, Result);
   3226     }
   3227     if (RCDecl && ObjCSynthesizedStructs.count(RCDecl)) {
   3228       Result = "\n    struct ";
   3229       Result += RCDecl->getNameAsString();
   3230       Result += "_IMPL ";
   3231       Result += RCDecl->getNameAsString();
   3232       Result += "_IVARS;\n";
   3233 
   3234       // insert the super class structure definition.
   3235       SourceLocation OnePastCurly =
   3236         LocStart.getLocWithOffset(cursor-startBuf+1);
   3237       InsertText(OnePastCurly, Result);
   3238     }
   3239     cursor++; // past '{'
   3240 
   3241     // Now comment out any visibility specifiers.
   3242     while (cursor < endBuf) {
   3243       if (*cursor == '@') {
   3244         SourceLocation atLoc = LocStart.getLocWithOffset(cursor-startBuf);
   3245         // Skip whitespace.
   3246         for (++cursor; cursor[0] == ' ' || cursor[0] == '\t'; ++cursor)
   3247           /*scan*/;
   3248 
   3249         // FIXME: presence of @public, etc. inside comment results in
   3250         // this transformation as well, which is still correct c-code.
   3251         if (!strncmp(cursor, "public", strlen("public")) ||
   3252             !strncmp(cursor, "private", strlen("private")) ||
   3253             !strncmp(cursor, "package", strlen("package")) ||
   3254             !strncmp(cursor, "protected", strlen("protected")))
   3255           InsertText(atLoc, "// ");
   3256       }
   3257       // FIXME: If there are cases where '<' is used in ivar declaration part
   3258       // of user code, then scan the ivar list and use needToScanForQualifiers
   3259       // for type checking.
   3260       else if (*cursor == '<') {
   3261         SourceLocation atLoc = LocStart.getLocWithOffset(cursor-startBuf);
   3262         InsertText(atLoc, "/* ");
   3263         cursor = strchr(cursor, '>');
   3264         cursor++;
   3265         atLoc = LocStart.getLocWithOffset(cursor-startBuf);
   3266         InsertText(atLoc, " */");
   3267       } else if (*cursor == '^') { // rewrite block specifier.
   3268         SourceLocation caretLoc = LocStart.getLocWithOffset(cursor-startBuf);
   3269         ReplaceText(caretLoc, 1, "*");
   3270       }
   3271       cursor++;
   3272     }
   3273     // Don't forget to add a ';'!!
   3274     InsertText(LocEnd.getLocWithOffset(1), ";");
   3275   } else { // we don't have any instance variables - insert super struct.
   3276     endBuf += Lexer::MeasureTokenLength(LocEnd, *SM, LangOpts);
   3277     Result += " {\n    struct ";
   3278     Result += RCDecl->getNameAsString();
   3279     Result += "_IMPL ";
   3280     Result += RCDecl->getNameAsString();
   3281     Result += "_IVARS;\n};\n";
   3282     ReplaceText(LocStart, endBuf-startBuf, Result);
   3283   }
   3284   // Mark this struct as having been generated.
   3285   if (!ObjCSynthesizedStructs.insert(CDecl))
   3286     llvm_unreachable("struct already synthesize- SynthesizeObjCInternalStruct");
   3287 }
   3288 
   3289 //===----------------------------------------------------------------------===//
   3290 // Meta Data Emission
   3291 //===----------------------------------------------------------------------===//
   3292 
   3293 
   3294 /// RewriteImplementations - This routine rewrites all method implementations
   3295 /// and emits meta-data.
   3296 
   3297 void RewriteObjC::RewriteImplementations() {
   3298   int ClsDefCount = ClassImplementation.size();
   3299   int CatDefCount = CategoryImplementation.size();
   3300 
   3301   // Rewrite implemented methods
   3302   for (int i = 0; i < ClsDefCount; i++)
   3303     RewriteImplementationDecl(ClassImplementation[i]);
   3304 
   3305   for (int i = 0; i < CatDefCount; i++)
   3306     RewriteImplementationDecl(CategoryImplementation[i]);
   3307 }
   3308 
   3309 void RewriteObjC::RewriteByRefString(std::string &ResultStr,
   3310                                      const std::string &Name,
   3311                                      ValueDecl *VD, bool def) {
   3312   assert(BlockByRefDeclNo.count(VD) &&
   3313          "RewriteByRefString: ByRef decl missing");
   3314   if (def)
   3315     ResultStr += "struct ";
   3316   ResultStr += "__Block_byref_" + Name +
   3317     "_" + utostr(BlockByRefDeclNo[VD]) ;
   3318 }
   3319 
   3320 static bool HasLocalVariableExternalStorage(ValueDecl *VD) {
   3321   if (VarDecl *Var = dyn_cast<VarDecl>(VD))
   3322     return (Var->isFunctionOrMethodVarDecl() && !Var->hasLocalStorage());
   3323   return false;
   3324 }
   3325 
   3326 std::string RewriteObjC::SynthesizeBlockFunc(BlockExpr *CE, int i,
   3327                                                    StringRef funcName,
   3328                                                    std::string Tag) {
   3329   const FunctionType *AFT = CE->getFunctionType();
   3330   QualType RT = AFT->getResultType();
   3331   std::string StructRef = "struct " + Tag;
   3332   std::string S = "static " + RT.getAsString(Context->getPrintingPolicy()) + " __" +
   3333                   funcName.str() + "_" + "block_func_" + utostr(i);
   3334 
   3335   BlockDecl *BD = CE->getBlockDecl();
   3336 
   3337   if (isa<FunctionNoProtoType>(AFT)) {
   3338     // No user-supplied arguments. Still need to pass in a pointer to the
   3339     // block (to reference imported block decl refs).
   3340     S += "(" + StructRef + " *__cself)";
   3341   } else if (BD->param_empty()) {
   3342     S += "(" + StructRef + " *__cself)";
   3343   } else {
   3344     const FunctionProtoType *FT = cast<FunctionProtoType>(AFT);
   3345     assert(FT && "SynthesizeBlockFunc: No function proto");
   3346     S += '(';
   3347     // first add the implicit argument.
   3348     S += StructRef + " *__cself, ";
   3349     std::string ParamStr;
   3350     for (BlockDecl::param_iterator AI = BD->param_begin(),
   3351          E = BD->param_end(); AI != E; ++AI) {
   3352       if (AI != BD->param_begin()) S += ", ";
   3353       ParamStr = (*AI)->getNameAsString();
   3354       QualType QT = (*AI)->getType();
   3355       (void)convertBlockPointerToFunctionPointer(QT);
   3356       QT.getAsStringInternal(ParamStr, Context->getPrintingPolicy());
   3357       S += ParamStr;
   3358     }
   3359     if (FT->isVariadic()) {
   3360       if (!BD->param_empty()) S += ", ";
   3361       S += "...";
   3362     }
   3363     S += ')';
   3364   }
   3365   S += " {\n";
   3366 
   3367   // Create local declarations to avoid rewriting all closure decl ref exprs.
   3368   // First, emit a declaration for all "by ref" decls.
   3369   for (SmallVectorImpl<ValueDecl *>::iterator I = BlockByRefDecls.begin(),
   3370        E = BlockByRefDecls.end(); I != E; ++I) {
   3371     S += "  ";
   3372     std::string Name = (*I)->getNameAsString();
   3373     std::string TypeString;
   3374     RewriteByRefString(TypeString, Name, (*I));
   3375     TypeString += " *";
   3376     Name = TypeString + Name;
   3377     S += Name + " = __cself->" + (*I)->getNameAsString() + "; // bound by ref\n";
   3378   }
   3379   // Next, emit a declaration for all "by copy" declarations.
   3380   for (SmallVectorImpl<ValueDecl *>::iterator I = BlockByCopyDecls.begin(),
   3381        E = BlockByCopyDecls.end(); I != E; ++I) {
   3382     S += "  ";
   3383     // Handle nested closure invocation. For example:
   3384     //
   3385     //   void (^myImportedClosure)(void);
   3386     //   myImportedClosure  = ^(void) { setGlobalInt(x + y); };
   3387     //
   3388     //   void (^anotherClosure)(void);
   3389     //   anotherClosure = ^(void) {
   3390     //     myImportedClosure(); // import and invoke the closure
   3391     //   };
   3392     //
   3393     if (isTopLevelBlockPointerType((*I)->getType())) {
   3394       RewriteBlockPointerTypeVariable(S, (*I));
   3395       S += " = (";
   3396       RewriteBlockPointerType(S, (*I)->getType());
   3397       S += ")";
   3398       S += "__cself->" + (*I)->getNameAsString() + "; // bound by copy\n";
   3399     }
   3400     else {
   3401       std::string Name = (*I)->getNameAsString();
   3402       QualType QT = (*I)->getType();
   3403       if (HasLocalVariableExternalStorage(*I))
   3404         QT = Context->getPointerType(QT);
   3405       QT.getAsStringInternal(Name, Context->getPrintingPolicy());
   3406       S += Name + " = __cself->" +
   3407                               (*I)->getNameAsString() + "; // bound by copy\n";
   3408     }
   3409   }
   3410   std::string RewrittenStr = RewrittenBlockExprs[CE];
   3411   const char *cstr = RewrittenStr.c_str();
   3412   while (*cstr++ != '{') ;
   3413   S += cstr;
   3414   S += "\n";
   3415   return S;
   3416 }
   3417 
   3418 std::string RewriteObjC::SynthesizeBlockHelperFuncs(BlockExpr *CE, int i,
   3419                                                    StringRef funcName,
   3420                                                    std::string Tag) {
   3421   std::string StructRef = "struct " + Tag;
   3422   std::string S = "static void __";
   3423 
   3424   S += funcName;
   3425   S += "_block_copy_" + utostr(i);
   3426   S += "(" + StructRef;
   3427   S += "*dst, " + StructRef;
   3428   S += "*src) {";
   3429   for (llvm::SmallPtrSet<ValueDecl*,8>::iterator I = ImportedBlockDecls.begin(),
   3430       E = ImportedBlockDecls.end(); I != E; ++I) {
   3431     ValueDecl *VD = (*I);
   3432     S += "_Block_object_assign((void*)&dst->";
   3433     S += (*I)->getNameAsString();
   3434     S += ", (void*)src->";
   3435     S += (*I)->getNameAsString();
   3436     if (BlockByRefDeclsPtrSet.count((*I)))
   3437       S += ", " + utostr(BLOCK_FIELD_IS_BYREF) + "/*BLOCK_FIELD_IS_BYREF*/);";
   3438     else if (VD->getType()->isBlockPointerType())
   3439       S += ", " + utostr(BLOCK_FIELD_IS_BLOCK) + "/*BLOCK_FIELD_IS_BLOCK*/);";
   3440     else
   3441       S += ", " + utostr(BLOCK_FIELD_IS_OBJECT) + "/*BLOCK_FIELD_IS_OBJECT*/);";
   3442   }
   3443   S += "}\n";
   3444 
   3445   S += "\nstatic void __";
   3446   S += funcName;
   3447   S += "_block_dispose_" + utostr(i);
   3448   S += "(" + StructRef;
   3449   S += "*src) {";
   3450   for (llvm::SmallPtrSet<ValueDecl*,8>::iterator I = ImportedBlockDecls.begin(),
   3451       E = ImportedBlockDecls.end(); I != E; ++I) {
   3452     ValueDecl *VD = (*I);
   3453     S += "_Block_object_dispose((void*)src->";
   3454     S += (*I)->getNameAsString();
   3455     if (BlockByRefDeclsPtrSet.count((*I)))
   3456       S += ", " + utostr(BLOCK_FIELD_IS_BYREF) + "/*BLOCK_FIELD_IS_BYREF*/);";
   3457     else if (VD->getType()->isBlockPointerType())
   3458       S += ", " + utostr(BLOCK_FIELD_IS_BLOCK) + "/*BLOCK_FIELD_IS_BLOCK*/);";
   3459     else
   3460       S += ", " + utostr(BLOCK_FIELD_IS_OBJECT) + "/*BLOCK_FIELD_IS_OBJECT*/);";
   3461   }
   3462   S += "}\n";
   3463   return S;
   3464 }
   3465 
   3466 std::string RewriteObjC::SynthesizeBlockImpl(BlockExpr *CE, std::string Tag,
   3467                                              std::string Desc) {
   3468   std::string S = "\nstruct " + Tag;
   3469   std::string Constructor = "  " + Tag;
   3470 
   3471   S += " {\n  struct __block_impl impl;\n";
   3472   S += "  struct " + Desc;
   3473   S += "* Desc;\n";
   3474 
   3475   Constructor += "(void *fp, "; // Invoke function pointer.
   3476   Constructor += "struct " + Desc; // Descriptor pointer.
   3477   Constructor += " *desc";
   3478 
   3479   if (BlockDeclRefs.size()) {
   3480     // Output all "by copy" declarations.
   3481     for (SmallVectorImpl<ValueDecl *>::iterator I = BlockByCopyDecls.begin(),
   3482          E = BlockByCopyDecls.end(); I != E; ++I) {
   3483       S += "  ";
   3484       std::string FieldName = (*I)->getNameAsString();
   3485       std::string ArgName = "_" + FieldName;
   3486       // Handle nested closure invocation. For example:
   3487       //
   3488       //   void (^myImportedBlock)(void);
   3489       //   myImportedBlock  = ^(void) { setGlobalInt(x + y); };
   3490       //
   3491       //   void (^anotherBlock)(void);
   3492       //   anotherBlock = ^(void) {
   3493       //     myImportedBlock(); // import and invoke the closure
   3494       //   };
   3495       //
   3496       if (isTopLevelBlockPointerType((*I)->getType())) {
   3497         S += "struct __block_impl *";
   3498         Constructor += ", void *" + ArgName;
   3499       } else {
   3500         QualType QT = (*I)->getType();
   3501         if (HasLocalVariableExternalStorage(*I))
   3502           QT = Context->getPointerType(QT);
   3503         QT.getAsStringInternal(FieldName, Context->getPrintingPolicy());
   3504         QT.getAsStringInternal(ArgName, Context->getPrintingPolicy());
   3505         Constructor += ", " + ArgName;
   3506       }
   3507       S += FieldName + ";\n";
   3508     }
   3509     // Output all "by ref" declarations.
   3510     for (SmallVectorImpl<ValueDecl *>::iterator I = BlockByRefDecls.begin(),
   3511          E = BlockByRefDecls.end(); I != E; ++I) {
   3512       S += "  ";
   3513       std::string FieldName = (*I)->getNameAsString();
   3514       std::string ArgName = "_" + FieldName;
   3515       {
   3516         std::string TypeString;
   3517         RewriteByRefString(TypeString, FieldName, (*I));
   3518         TypeString += " *";
   3519         FieldName = TypeString + FieldName;
   3520         ArgName = TypeString + ArgName;
   3521         Constructor += ", " + ArgName;
   3522       }
   3523       S += FieldName + "; // by ref\n";
   3524     }
   3525     // Finish writing the constructor.
   3526     Constructor += ", int flags=0)";
   3527     // Initialize all "by copy" arguments.
   3528     bool firsTime = true;
   3529     for (SmallVectorImpl<ValueDecl *>::iterator I = BlockByCopyDecls.begin(),
   3530          E = BlockByCopyDecls.end(); I != E; ++I) {
   3531       std::string Name = (*I)->getNameAsString();
   3532         if (firsTime) {
   3533           Constructor += " : ";
   3534           firsTime = false;
   3535         }
   3536         else
   3537           Constructor += ", ";
   3538         if (isTopLevelBlockPointerType((*I)->getType()))
   3539           Constructor += Name + "((struct __block_impl *)_" + Name + ")";
   3540         else
   3541           Constructor += Name + "(_" + Name + ")";
   3542     }
   3543     // Initialize all "by ref" arguments.
   3544     for (SmallVectorImpl<ValueDecl *>::iterator I = BlockByRefDecls.begin(),
   3545          E = BlockByRefDecls.end(); I != E; ++I) {
   3546       std::string Name = (*I)->getNameAsString();
   3547       if (firsTime) {
   3548         Constructor += " : ";
   3549         firsTime = false;
   3550       }
   3551       else
   3552         Constructor += ", ";
   3553       Constructor += Name + "(_" + Name + "->__forwarding)";
   3554     }
   3555 
   3556     Constructor += " {\n";
   3557     if (GlobalVarDecl)
   3558       Constructor += "    impl.isa = &_NSConcreteGlobalBlock;\n";
   3559     else
   3560       Constructor += "    impl.isa = &_NSConcreteStackBlock;\n";
   3561     Constructor += "    impl.Flags = flags;\n    impl.FuncPtr = fp;\n";
   3562 
   3563     Constructor += "    Desc = desc;\n";
   3564   } else {
   3565     // Finish writing the constructor.
   3566     Constructor += ", int flags=0) {\n";
   3567     if (GlobalVarDecl)
   3568       Constructor += "    impl.isa = &_NSConcreteGlobalBlock;\n";
   3569     else
   3570       Constructor += "    impl.isa = &_NSConcreteStackBlock;\n";
   3571     Constructor += "    impl.Flags = flags;\n    impl.FuncPtr = fp;\n";
   3572     Constructor += "    Desc = desc;\n";
   3573   }
   3574   Constructor += "  ";
   3575   Constructor += "}\n";
   3576   S += Constructor;
   3577   S += "};\n";
   3578   return S;
   3579 }
   3580 
   3581 std::string RewriteObjC::SynthesizeBlockDescriptor(std::string DescTag,
   3582                                                    std::string ImplTag, int i,
   3583                                                    StringRef FunName,
   3584                                                    unsigned hasCopy) {
   3585   std::string S = "\nstatic struct " + DescTag;
   3586 
   3587   S += " {\n  unsigned long reserved;\n";
   3588   S += "  unsigned long Block_size;\n";
   3589   if (hasCopy) {
   3590     S += "  void (*copy)(struct ";
   3591     S += ImplTag; S += "*, struct ";
   3592     S += ImplTag; S += "*);\n";
   3593 
   3594     S += "  void (*dispose)(struct ";
   3595     S += ImplTag; S += "*);\n";
   3596   }
   3597   S += "} ";
   3598 
   3599   S += DescTag + "_DATA = { 0, sizeof(struct ";
   3600   S += ImplTag + ")";
   3601   if (hasCopy) {
   3602     S += ", __" + FunName.str() + "_block_copy_" + utostr(i);
   3603     S += ", __" + FunName.str() + "_block_dispose_" + utostr(i);
   3604   }
   3605   S += "};\n";
   3606   return S;
   3607 }
   3608 
   3609 void RewriteObjC::SynthesizeBlockLiterals(SourceLocation FunLocStart,
   3610                                           StringRef FunName) {
   3611   // Insert declaration for the function in which block literal is used.
   3612   if (CurFunctionDeclToDeclareForBlock && !Blocks.empty())
   3613     RewriteBlockLiteralFunctionDecl(CurFunctionDeclToDeclareForBlock);
   3614   bool RewriteSC = (GlobalVarDecl &&
   3615                     !Blocks.empty() &&
   3616                     GlobalVarDecl->getStorageClass() == SC_Static &&
   3617                     GlobalVarDecl->getType().getCVRQualifiers());
   3618   if (RewriteSC) {
   3619     std::string SC(" void __");
   3620     SC += GlobalVarDecl->getNameAsString();
   3621     SC += "() {}";
   3622     InsertText(FunLocStart, SC);
   3623   }
   3624 
   3625   // Insert closures that were part of the function.
   3626   for (unsigned i = 0, count=0; i < Blocks.size(); i++) {
   3627     CollectBlockDeclRefInfo(Blocks[i]);
   3628     // Need to copy-in the inner copied-in variables not actually used in this
   3629     // block.
   3630     for (int j = 0; j < InnerDeclRefsCount[i]; j++) {
   3631       DeclRefExpr *Exp = InnerDeclRefs[count++];
   3632       ValueDecl *VD = Exp->getDecl();
   3633       BlockDeclRefs.push_back(Exp);
   3634       if (!VD->hasAttr<BlocksAttr>() && !BlockByCopyDeclsPtrSet.count(VD)) {
   3635         BlockByCopyDeclsPtrSet.insert(VD);
   3636         BlockByCopyDecls.push_back(VD);
   3637       }
   3638       if (VD->hasAttr<BlocksAttr>() && !BlockByRefDeclsPtrSet.count(VD)) {
   3639         BlockByRefDeclsPtrSet.insert(VD);
   3640         BlockByRefDecls.push_back(VD);
   3641       }
   3642       // imported objects in the inner blocks not used in the outer
   3643       // blocks must be copied/disposed in the outer block as well.
   3644       if (VD->hasAttr<BlocksAttr>() ||
   3645           VD->getType()->isObjCObjectPointerType() ||
   3646           VD->getType()->isBlockPointerType())
   3647         ImportedBlockDecls.insert(VD);
   3648     }
   3649 
   3650     std::string ImplTag = "__" + FunName.str() + "_block_impl_" + utostr(i);
   3651     std::string DescTag = "__" + FunName.str() + "_block_desc_" + utostr(i);
   3652 
   3653     std::string CI = SynthesizeBlockImpl(Blocks[i], ImplTag, DescTag);
   3654 
   3655     InsertText(FunLocStart, CI);
   3656 
   3657     std::string CF = SynthesizeBlockFunc(Blocks[i], i, FunName, ImplTag);
   3658 
   3659     InsertText(FunLocStart, CF);
   3660 
   3661     if (ImportedBlockDecls.size()) {
   3662       std::string HF = SynthesizeBlockHelperFuncs(Blocks[i], i, FunName, ImplTag);
   3663       InsertText(FunLocStart, HF);
   3664     }
   3665     std::string BD = SynthesizeBlockDescriptor(DescTag, ImplTag, i, FunName,
   3666                                                ImportedBlockDecls.size() > 0);
   3667     InsertText(FunLocStart, BD);
   3668 
   3669     BlockDeclRefs.clear();
   3670     BlockByRefDecls.clear();
   3671     BlockByRefDeclsPtrSet.clear();
   3672     BlockByCopyDecls.clear();
   3673     BlockByCopyDeclsPtrSet.clear();
   3674     ImportedBlockDecls.clear();
   3675   }
   3676   if (RewriteSC) {
   3677     // Must insert any 'const/volatile/static here. Since it has been
   3678     // removed as result of rewriting of block literals.
   3679     std::string SC;
   3680     if (GlobalVarDecl->getStorageClass() == SC_Static)
   3681       SC = "static ";
   3682     if (GlobalVarDecl->getType().isConstQualified())
   3683       SC += "const ";
   3684     if (GlobalVarDecl->getType().isVolatileQualified())
   3685       SC += "volatile ";
   3686     if (GlobalVarDecl->getType().isRestrictQualified())
   3687       SC += "restrict ";
   3688     InsertText(FunLocStart, SC);
   3689   }
   3690 
   3691   Blocks.clear();
   3692   InnerDeclRefsCount.clear();
   3693   InnerDeclRefs.clear();
   3694   RewrittenBlockExprs.clear();
   3695 }
   3696 
   3697 void RewriteObjC::InsertBlockLiteralsWithinFunction(FunctionDecl *FD) {
   3698   SourceLocation FunLocStart = FD->getTypeSpecStartLoc();
   3699   StringRef FuncName = FD->getName();
   3700 
   3701   SynthesizeBlockLiterals(FunLocStart, FuncName);
   3702 }
   3703 
   3704 static void BuildUniqueMethodName(std::string &Name,
   3705                                   ObjCMethodDecl *MD) {
   3706   ObjCInterfaceDecl *IFace = MD->getClassInterface();
   3707   Name = IFace->getName();
   3708   Name += "__" + MD->getSelector().getAsString();
   3709   // Convert colons to underscores.
   3710   std::string::size_type loc = 0;
   3711   while ((loc = Name.find(":", loc)) != std::string::npos)
   3712     Name.replace(loc, 1, "_");
   3713 }
   3714 
   3715 void RewriteObjC::InsertBlockLiteralsWithinMethod(ObjCMethodDecl *MD) {
   3716   //fprintf(stderr,"In InsertBlockLiteralsWitinMethod\n");
   3717   //SourceLocation FunLocStart = MD->getLocStart();
   3718   SourceLocation FunLocStart = MD->getLocStart();
   3719   std::string FuncName;
   3720   BuildUniqueMethodName(FuncName, MD);
   3721   SynthesizeBlockLiterals(FunLocStart, FuncName);
   3722 }
   3723 
   3724 void RewriteObjC::GetBlockDeclRefExprs(Stmt *S) {
   3725   for (Stmt::child_range CI = S->children(); CI; ++CI)
   3726     if (*CI) {
   3727       if (BlockExpr *CBE = dyn_cast<BlockExpr>(*CI))
   3728         GetBlockDeclRefExprs(CBE->getBody());
   3729       else
   3730         GetBlockDeclRefExprs(*CI);
   3731     }
   3732   // Handle specific things.
   3733   if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(S)) {
   3734     if (DRE->refersToEnclosingLocal()) {
   3735       // FIXME: Handle enums.
   3736       if (!isa<FunctionDecl>(DRE->getDecl()))
   3737         BlockDeclRefs.push_back(DRE);
   3738       if (HasLocalVariableExternalStorage(DRE->getDecl()))
   3739         BlockDeclRefs.push_back(DRE);
   3740     }
   3741   }
   3742 
   3743   return;
   3744 }
   3745 
   3746 void RewriteObjC::GetInnerBlockDeclRefExprs(Stmt *S,
   3747                 SmallVectorImpl<DeclRefExpr *> &InnerBlockDeclRefs,
   3748                 llvm::SmallPtrSet<const DeclContext *, 8> &InnerContexts) {
   3749   for (Stmt::child_range CI = S->children(); CI; ++CI)
   3750     if (*CI) {
   3751       if (BlockExpr *CBE = dyn_cast<BlockExpr>(*CI)) {
   3752         InnerContexts.insert(cast<DeclContext>(CBE->getBlockDecl()));
   3753         GetInnerBlockDeclRefExprs(CBE->getBody(),
   3754                                   InnerBlockDeclRefs,
   3755                                   InnerContexts);
   3756       }
   3757       else
   3758         GetInnerBlockDeclRefExprs(*CI,
   3759                                   InnerBlockDeclRefs,
   3760                                   InnerContexts);
   3761 
   3762     }
   3763   // Handle specific things.
   3764   if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(S)) {
   3765     if (DRE->refersToEnclosingLocal()) {
   3766       if (!isa<FunctionDecl>(DRE->getDecl()) &&
   3767           !InnerContexts.count(DRE->getDecl()->getDeclContext()))
   3768         InnerBlockDeclRefs.push_back(DRE);
   3769       if (VarDecl *Var = dyn_cast<VarDecl>(DRE->getDecl()))
   3770         if (Var->isFunctionOrMethodVarDecl())
   3771           ImportedLocalExternalDecls.insert(Var);
   3772     }
   3773   }
   3774 
   3775   return;
   3776 }
   3777 
   3778 /// convertFunctionTypeOfBlocks - This routine converts a function type
   3779 /// whose result type may be a block pointer or whose argument type(s)
   3780 /// might be block pointers to an equivalent function type replacing
   3781 /// all block pointers to function pointers.
   3782 QualType RewriteObjC::convertFunctionTypeOfBlocks(const FunctionType *FT) {
   3783   const FunctionProtoType *FTP = dyn_cast<FunctionProtoType>(FT);
   3784   // FTP will be null for closures that don't take arguments.
   3785   // Generate a funky cast.
   3786   SmallVector<QualType, 8> ArgTypes;
   3787   QualType Res = FT->getResultType();
   3788   bool HasBlockType = convertBlockPointerToFunctionPointer(Res);
   3789 
   3790   if (FTP) {
   3791     for (FunctionProtoType::arg_type_iterator I = FTP->arg_type_begin(),
   3792          E = FTP->arg_type_end(); I && (I != E); ++I) {
   3793       QualType t = *I;
   3794       // Make sure we convert "t (^)(...)" to "t (*)(...)".
   3795       if (convertBlockPointerToFunctionPointer(t))
   3796         HasBlockType = true;
   3797       ArgTypes.push_back(t);
   3798     }
   3799   }
   3800   QualType FuncType;
   3801   // FIXME. Does this work if block takes no argument but has a return type
   3802   // which is of block type?
   3803   if (HasBlockType)
   3804     FuncType = getSimpleFunctionType(Res, ArgTypes);
   3805   else FuncType = QualType(FT, 0);
   3806   return FuncType;
   3807 }
   3808 
   3809 Stmt *RewriteObjC::SynthesizeBlockCall(CallExpr *Exp, const Expr *BlockExp) {
   3810   // Navigate to relevant type information.
   3811   const BlockPointerType *CPT = 0;
   3812 
   3813   if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(BlockExp)) {
   3814     CPT = DRE->getType()->getAs<BlockPointerType>();
   3815   } else if (const MemberExpr *MExpr = dyn_cast<MemberExpr>(BlockExp)) {
   3816     CPT = MExpr->getType()->getAs<BlockPointerType>();
   3817   }
   3818   else if (const ParenExpr *PRE = dyn_cast<ParenExpr>(BlockExp)) {
   3819     return SynthesizeBlockCall(Exp, PRE->getSubExpr());
   3820   }
   3821   else if (const ImplicitCastExpr *IEXPR = dyn_cast<ImplicitCastExpr>(BlockExp))
   3822     CPT = IEXPR->getType()->getAs<BlockPointerType>();
   3823   else if (const ConditionalOperator *CEXPR =
   3824             dyn_cast<ConditionalOperator>(BlockExp)) {
   3825     Expr *LHSExp = CEXPR->getLHS();
   3826     Stmt *LHSStmt = SynthesizeBlockCall(Exp, LHSExp);
   3827     Expr *RHSExp = CEXPR->getRHS();
   3828     Stmt *RHSStmt = SynthesizeBlockCall(Exp, RHSExp);
   3829     Expr *CONDExp = CEXPR->getCond();
   3830     ConditionalOperator *CondExpr =
   3831       new (Context) ConditionalOperator(CONDExp,
   3832                                       SourceLocation(), cast<Expr>(LHSStmt),
   3833                                       SourceLocation(), cast<Expr>(RHSStmt),
   3834                                       Exp->getType(), VK_RValue, OK_Ordinary);
   3835     return CondExpr;
   3836   } else if (const ObjCIvarRefExpr *IRE = dyn_cast<ObjCIvarRefExpr>(BlockExp)) {
   3837     CPT = IRE->getType()->getAs<BlockPointerType>();
   3838   } else if (const PseudoObjectExpr *POE
   3839                = dyn_cast<PseudoObjectExpr>(BlockExp)) {
   3840     CPT = POE->getType()->castAs<BlockPointerType>();
   3841   } else {
   3842     assert(1 && "RewriteBlockClass: Bad type");
   3843   }
   3844   assert(CPT && "RewriteBlockClass: Bad type");
   3845   const FunctionType *FT = CPT->getPointeeType()->getAs<FunctionType>();
   3846   assert(FT && "RewriteBlockClass: Bad type");
   3847   const FunctionProtoType *FTP = dyn_cast<FunctionProtoType>(FT);
   3848   // FTP will be null for closures that don't take arguments.
   3849 
   3850   RecordDecl *RD = RecordDecl::Create(*Context, TTK_Struct, TUDecl,
   3851                                       SourceLocation(), SourceLocation(),
   3852                                       &Context->Idents.get("__block_impl"));
   3853   QualType PtrBlock = Context->getPointerType(Context->getTagDeclType(RD));
   3854 
   3855   // Generate a funky cast.
   3856   SmallVector<QualType, 8> ArgTypes;
   3857 
   3858   // Push the block argument type.
   3859   ArgTypes.push_back(PtrBlock);
   3860   if (FTP) {
   3861     for (FunctionProtoType::arg_type_iterator I = FTP->arg_type_begin(),
   3862          E = FTP->arg_type_end(); I && (I != E); ++I) {
   3863       QualType t = *I;
   3864       // Make sure we convert "t (^)(...)" to "t (*)(...)".
   3865       if (!convertBlockPointerToFunctionPointer(t))
   3866         convertToUnqualifiedObjCType(t);
   3867       ArgTypes.push_back(t);
   3868     }
   3869   }
   3870   // Now do the pointer to function cast.
   3871   QualType PtrToFuncCastType = getSimpleFunctionType(Exp->getType(), ArgTypes);
   3872 
   3873   PtrToFuncCastType = Context->getPointerType(PtrToFuncCastType);
   3874 
   3875   CastExpr *BlkCast = NoTypeInfoCStyleCastExpr(Context, PtrBlock,
   3876                                                CK_BitCast,
   3877                                                const_cast<Expr*>(BlockExp));
   3878   // Don't forget the parens to enforce the proper binding.
   3879   ParenExpr *PE = new (Context) ParenExpr(SourceLocation(), SourceLocation(),
   3880                                           BlkCast);
   3881   //PE->dump();
   3882 
   3883   FieldDecl *FD = FieldDecl::Create(*Context, 0, SourceLocation(),
   3884                                     SourceLocation(),
   3885                                     &Context->Idents.get("FuncPtr"),
   3886                                     Context->VoidPtrTy, 0,
   3887                                     /*BitWidth=*/0, /*Mutable=*/true,
   3888                                     ICIS_NoInit);
   3889   MemberExpr *ME = new (Context) MemberExpr(PE, true, FD, SourceLocation(),
   3890                                             FD->getType(), VK_LValue,
   3891                                             OK_Ordinary);
   3892 
   3893 
   3894   CastExpr *FunkCast = NoTypeInfoCStyleCastExpr(Context, PtrToFuncCastType,
   3895                                                 CK_BitCast, ME);
   3896   PE = new (Context) ParenExpr(SourceLocation(), SourceLocation(), FunkCast);
   3897 
   3898   SmallVector<Expr*, 8> BlkExprs;
   3899   // Add the implicit argument.
   3900   BlkExprs.push_back(BlkCast);
   3901   // Add the user arguments.
   3902   for (CallExpr::arg_iterator I = Exp->arg_begin(),
   3903        E = Exp->arg_end(); I != E; ++I) {
   3904     BlkExprs.push_back(*I);
   3905   }
   3906   CallExpr *CE = new (Context) CallExpr(*Context, PE, BlkExprs,
   3907                                         Exp->getType(), VK_RValue,
   3908                                         SourceLocation());
   3909   return CE;
   3910 }
   3911 
   3912 // We need to return the rewritten expression to handle cases where the
   3913 // BlockDeclRefExpr is embedded in another expression being rewritten.
   3914 // For example:
   3915 //
   3916 // int main() {
   3917 //    __block Foo *f;
   3918 //    __block int i;
   3919 //
   3920 //    void (^myblock)() = ^() {
   3921 //        [f test]; // f is a BlockDeclRefExpr embedded in a message (which is being rewritten).
   3922 //        i = 77;
   3923 //    };
   3924 //}
   3925 Stmt *RewriteObjC::RewriteBlockDeclRefExpr(DeclRefExpr *DeclRefExp) {
   3926   // Rewrite the byref variable into BYREFVAR->__forwarding->BYREFVAR
   3927   // for each DeclRefExp where BYREFVAR is name of the variable.
   3928   ValueDecl *VD = DeclRefExp->getDecl();
   3929   bool isArrow = DeclRefExp->refersToEnclosingLocal();
   3930 
   3931   FieldDecl *FD = FieldDecl::Create(*Context, 0, SourceLocation(),
   3932                                     SourceLocation(),
   3933                                     &Context->Idents.get("__forwarding"),
   3934                                     Context->VoidPtrTy, 0,
   3935                                     /*BitWidth=*/0, /*Mutable=*/true,
   3936                                     ICIS_NoInit);
   3937   MemberExpr *ME = new (Context) MemberExpr(DeclRefExp, isArrow,
   3938                                             FD, SourceLocation(),
   3939                                             FD->getType(), VK_LValue,
   3940                                             OK_Ordinary);
   3941 
   3942   StringRef Name = VD->getName();
   3943   FD = FieldDecl::Create(*Context, 0, SourceLocation(), SourceLocation(),
   3944                          &Context->Idents.get(Name),
   3945                          Context->VoidPtrTy, 0,
   3946                          /*BitWidth=*/0, /*Mutable=*/true,
   3947                          ICIS_NoInit);
   3948   ME = new (Context) MemberExpr(ME, true, FD, SourceLocation(),
   3949                                 DeclRefExp->getType(), VK_LValue, OK_Ordinary);
   3950 
   3951 
   3952 
   3953   // Need parens to enforce precedence.
   3954   ParenExpr *PE = new (Context) ParenExpr(DeclRefExp->getExprLoc(),
   3955                                           DeclRefExp->getExprLoc(),
   3956                                           ME);
   3957   ReplaceStmt(DeclRefExp, PE);
   3958   return PE;
   3959 }
   3960 
   3961 // Rewrites the imported local variable V with external storage
   3962 // (static, extern, etc.) as *V
   3963 //
   3964 Stmt *RewriteObjC::RewriteLocalVariableExternalStorage(DeclRefExpr *DRE) {
   3965   ValueDecl *VD = DRE->getDecl();
   3966   if (VarDecl *Var = dyn_cast<VarDecl>(VD))
   3967     if (!ImportedLocalExternalDecls.count(Var))
   3968       return DRE;
   3969   Expr *Exp = new (Context) UnaryOperator(DRE, UO_Deref, DRE->getType(),
   3970                                           VK_LValue, OK_Ordinary,
   3971                                           DRE->getLocation());
   3972   // Need parens to enforce precedence.
   3973   ParenExpr *PE = new (Context) ParenExpr(SourceLocation(), SourceLocation(),
   3974                                           Exp);
   3975   ReplaceStmt(DRE, PE);
   3976   return PE;
   3977 }
   3978 
   3979 void RewriteObjC::RewriteCastExpr(CStyleCastExpr *CE) {
   3980   SourceLocation LocStart = CE->getLParenLoc();
   3981   SourceLocation LocEnd = CE->getRParenLoc();
   3982 
   3983   // Need to avoid trying to rewrite synthesized casts.
   3984   if (LocStart.isInvalid())
   3985     return;
   3986   // Need to avoid trying to rewrite casts contained in macros.
   3987   if (!Rewriter::isRewritable(LocStart) || !Rewriter::isRewritable(LocEnd))
   3988     return;
   3989 
   3990   const char *startBuf = SM->getCharacterData(LocStart);
   3991   const char *endBuf = SM->getCharacterData(LocEnd);
   3992   QualType QT = CE->getType();
   3993   const Type* TypePtr = QT->getAs<Type>();
   3994   if (isa<TypeOfExprType>(TypePtr)) {
   3995     const TypeOfExprType *TypeOfExprTypePtr = cast<TypeOfExprType>(TypePtr);
   3996     QT = TypeOfExprTypePtr->getUnderlyingExpr()->getType();
   3997     std::string TypeAsString = "(";
   3998     RewriteBlockPointerType(TypeAsString, QT);
   3999     TypeAsString += ")";
   4000     ReplaceText(LocStart, endBuf-startBuf+1, TypeAsString);
   4001     return;
   4002   }
   4003   // advance the location to startArgList.
   4004   const char *argPtr = startBuf;
   4005 
   4006   while (*argPtr++ && (argPtr < endBuf)) {
   4007     switch (*argPtr) {
   4008     case '^':
   4009       // Replace the '^' with '*'.
   4010       LocStart = LocStart.getLocWithOffset(argPtr-startBuf);
   4011       ReplaceText(LocStart, 1, "*");
   4012       break;
   4013     }
   4014   }
   4015   return;
   4016 }
   4017 
   4018 void RewriteObjC::RewriteBlockPointerFunctionArgs(FunctionDecl *FD) {
   4019   SourceLocation DeclLoc = FD->getLocation();
   4020   unsigned parenCount = 0;
   4021 
   4022   // We have 1 or more arguments that have closure pointers.
   4023   const char *startBuf = SM->getCharacterData(DeclLoc);
   4024   const char *startArgList = strchr(startBuf, '(');
   4025 
   4026   assert((*startArgList == '(') && "Rewriter fuzzy parser confused");
   4027 
   4028   parenCount++;
   4029   // advance the location to startArgList.
   4030   DeclLoc = DeclLoc.getLocWithOffset(startArgList-startBuf);
   4031   assert((DeclLoc.isValid()) && "Invalid DeclLoc");
   4032 
   4033   const char *argPtr = startArgList;
   4034 
   4035   while (*argPtr++ && parenCount) {
   4036     switch (*argPtr) {
   4037     case '^':
   4038       // Replace the '^' with '*'.
   4039       DeclLoc = DeclLoc.getLocWithOffset(argPtr-startArgList);
   4040       ReplaceText(DeclLoc, 1, "*");
   4041       break;
   4042     case '(':
   4043       parenCount++;
   4044       break;
   4045     case ')':
   4046       parenCount--;
   4047       break;
   4048     }
   4049   }
   4050   return;
   4051 }
   4052 
   4053 bool RewriteObjC::PointerTypeTakesAnyBlockArguments(QualType QT) {
   4054   const FunctionProtoType *FTP;
   4055   const PointerType *PT = QT->getAs<PointerType>();
   4056   if (PT) {
   4057     FTP = PT->getPointeeType()->getAs<FunctionProtoType>();
   4058   } else {
   4059     const BlockPointerType *BPT = QT->getAs<BlockPointerType>();
   4060     assert(BPT && "BlockPointerTypeTakeAnyBlockArguments(): not a block pointer type");
   4061     FTP = BPT->getPointeeType()->getAs<FunctionProtoType>();
   4062   }
   4063   if (FTP) {
   4064     for (FunctionProtoType::arg_type_iterator I = FTP->arg_type_begin(),
   4065          E = FTP->arg_type_end(); I != E; ++I)
   4066       if (isTopLevelBlockPointerType(*I))
   4067         return true;
   4068   }
   4069   return false;
   4070 }
   4071 
   4072 bool RewriteObjC::PointerTypeTakesAnyObjCQualifiedType(QualType QT) {
   4073   const FunctionProtoType *FTP;
   4074   const PointerType *PT = QT->getAs<PointerType>();
   4075   if (PT) {
   4076     FTP = PT->getPointeeType()->getAs<FunctionProtoType>();
   4077   } else {
   4078     const BlockPointerType *BPT = QT->getAs<BlockPointerType>();
   4079     assert(BPT && "BlockPointerTypeTakeAnyBlockArguments(): not a block pointer type");
   4080     FTP = BPT->getPointeeType()->getAs<FunctionProtoType>();
   4081   }
   4082   if (FTP) {
   4083     for (FunctionProtoType::arg_type_iterator I = FTP->arg_type_begin(),
   4084          E = FTP->arg_type_end(); I != E; ++I) {
   4085       if ((*I)->isObjCQualifiedIdType())
   4086         return true;
   4087       if ((*I)->isObjCObjectPointerType() &&
   4088           (*I)->getPointeeType()->isObjCQualifiedInterfaceType())
   4089         return true;
   4090     }
   4091 
   4092   }
   4093   return false;
   4094 }
   4095 
   4096 void RewriteObjC::GetExtentOfArgList(const char *Name, const char *&LParen,
   4097                                      const char *&RParen) {
   4098   const char *argPtr = strchr(Name, '(');
   4099   assert((*argPtr == '(') && "Rewriter fuzzy parser confused");
   4100 
   4101   LParen = argPtr; // output the start.
   4102   argPtr++; // skip past the left paren.
   4103   unsigned parenCount = 1;
   4104 
   4105   while (*argPtr && parenCount) {
   4106     switch (*argPtr) {
   4107     case '(': parenCount++; break;
   4108     case ')': parenCount--; break;
   4109     default: break;
   4110     }
   4111     if (parenCount) argPtr++;
   4112   }
   4113   assert((*argPtr == ')') && "Rewriter fuzzy parser confused");
   4114   RParen = argPtr; // output the end
   4115 }
   4116 
   4117 void RewriteObjC::RewriteBlockPointerDecl(NamedDecl *ND) {
   4118   if (FunctionDecl *FD = dyn_cast<FunctionDecl>(ND)) {
   4119     RewriteBlockPointerFunctionArgs(FD);
   4120     return;
   4121   }
   4122   // Handle Variables and Typedefs.
   4123   SourceLocation DeclLoc = ND->getLocation();
   4124   QualType DeclT;
   4125   if (VarDecl *VD = dyn_cast<VarDecl>(ND))
   4126     DeclT = VD->getType();
   4127   else if (TypedefNameDecl *TDD = dyn_cast<TypedefNameDecl>(ND))
   4128     DeclT = TDD->getUnderlyingType();
   4129   else if (FieldDecl *FD = dyn_cast<FieldDecl>(ND))
   4130     DeclT = FD->getType();
   4131   else
   4132     llvm_unreachable("RewriteBlockPointerDecl(): Decl type not yet handled");
   4133 
   4134   const char *startBuf = SM->getCharacterData(DeclLoc);
   4135   const char *endBuf = startBuf;
   4136   // scan backward (from the decl location) for the end of the previous decl.
   4137   while (*startBuf != '^' && *startBuf != ';' && startBuf != MainFileStart)
   4138     startBuf--;
   4139   SourceLocation Start = DeclLoc.getLocWithOffset(startBuf-endBuf);
   4140   std::string buf;
   4141   unsigned OrigLength=0;
   4142   // *startBuf != '^' if we are dealing with a pointer to function that
   4143   // may take block argument types (which will be handled below).
   4144   if (*startBuf == '^') {
   4145     // Replace the '^' with '*', computing a negative offset.
   4146     buf = '*';
   4147     startBuf++;
   4148     OrigLength++;
   4149   }
   4150   while (*startBuf != ')') {
   4151     buf += *startBuf;
   4152     startBuf++;
   4153     OrigLength++;
   4154   }
   4155   buf += ')';
   4156   OrigLength++;
   4157 
   4158   if (PointerTypeTakesAnyBlockArguments(DeclT) ||
   4159       PointerTypeTakesAnyObjCQualifiedType(DeclT)) {
   4160     // Replace the '^' with '*' for arguments.
   4161     // Replace id<P> with id/*<>*/
   4162     DeclLoc = ND->getLocation();
   4163     startBuf = SM->getCharacterData(DeclLoc);
   4164     const char *argListBegin, *argListEnd;
   4165     GetExtentOfArgList(startBuf, argListBegin, argListEnd);
   4166     while (argListBegin < argListEnd) {
   4167       if (*argListBegin == '^')
   4168         buf += '*';
   4169       else if (*argListBegin ==  '<') {
   4170         buf += "/*";
   4171         buf += *argListBegin++;
   4172         OrigLength++;
   4173         while (*argListBegin != '>') {
   4174           buf += *argListBegin++;
   4175           OrigLength++;
   4176         }
   4177         buf += *argListBegin;
   4178         buf += "*/";
   4179       }
   4180       else
   4181         buf += *argListBegin;
   4182       argListBegin++;
   4183       OrigLength++;
   4184     }
   4185     buf += ')';
   4186     OrigLength++;
   4187   }
   4188   ReplaceText(Start, OrigLength, buf);
   4189 
   4190   return;
   4191 }
   4192 
   4193 
   4194 /// SynthesizeByrefCopyDestroyHelper - This routine synthesizes:
   4195 /// void __Block_byref_id_object_copy(struct Block_byref_id_object *dst,
   4196 ///                    struct Block_byref_id_object *src) {
   4197 ///  _Block_object_assign (&_dest->object, _src->object,
   4198 ///                        BLOCK_BYREF_CALLER | BLOCK_FIELD_IS_OBJECT
   4199 ///                        [|BLOCK_FIELD_IS_WEAK]) // object
   4200 ///  _Block_object_assign(&_dest->object, _src->object,
   4201 ///                       BLOCK_BYREF_CALLER | BLOCK_FIELD_IS_BLOCK
   4202 ///                       [|BLOCK_FIELD_IS_WEAK]) // block
   4203 /// }
   4204 /// And:
   4205 /// void __Block_byref_id_object_dispose(struct Block_byref_id_object *_src) {
   4206 ///  _Block_object_dispose(_src->object,
   4207 ///                        BLOCK_BYREF_CALLER | BLOCK_FIELD_IS_OBJECT
   4208 ///                        [|BLOCK_FIELD_IS_WEAK]) // object
   4209 ///  _Block_object_dispose(_src->object,
   4210 ///                         BLOCK_BYREF_CALLER | BLOCK_FIELD_IS_BLOCK
   4211 ///                         [|BLOCK_FIELD_IS_WEAK]) // block
   4212 /// }
   4213 
   4214 std::string RewriteObjC::SynthesizeByrefCopyDestroyHelper(VarDecl *VD,
   4215                                                           int flag) {
   4216   std::string S;
   4217   if (CopyDestroyCache.count(flag))
   4218     return S;
   4219   CopyDestroyCache.insert(flag);
   4220   S = "static void __Block_byref_id_object_copy_";
   4221   S += utostr(flag);
   4222   S += "(void *dst, void *src) {\n";
   4223 
   4224   // offset into the object pointer is computed as:
   4225   // void * + void* + int + int + void* + void *
   4226   unsigned IntSize =
   4227   static_cast<unsigned>(Context->getTypeSize(Context->IntTy));
   4228   unsigned VoidPtrSize =
   4229   static_cast<unsigned>(Context->getTypeSize(Context->VoidPtrTy));
   4230 
   4231   unsigned offset = (VoidPtrSize*4 + IntSize + IntSize)/Context->getCharWidth();
   4232   S += " _Block_object_assign((char*)dst + ";
   4233   S += utostr(offset);
   4234   S += ", *(void * *) ((char*)src + ";
   4235   S += utostr(offset);
   4236   S += "), ";
   4237   S += utostr(flag);
   4238   S += ");\n}\n";
   4239 
   4240   S += "static void __Block_byref_id_object_dispose_";
   4241   S += utostr(flag);
   4242   S += "(void *src) {\n";
   4243   S += " _Block_object_dispose(*(void * *) ((char*)src + ";
   4244   S += utostr(offset);
   4245   S += "), ";
   4246   S += utostr(flag);
   4247   S += ");\n}\n";
   4248   return S;
   4249 }
   4250 
   4251 /// RewriteByRefVar - For each __block typex ND variable this routine transforms
   4252 /// the declaration into:
   4253 /// struct __Block_byref_ND {
   4254 /// void *__isa;                  // NULL for everything except __weak pointers
   4255 /// struct __Block_byref_ND *__forwarding;
   4256 /// int32_t __flags;
   4257 /// int32_t __size;
   4258 /// void *__Block_byref_id_object_copy; // If variable is __block ObjC object
   4259 /// void *__Block_byref_id_object_dispose; // If variable is __block ObjC object
   4260 /// typex ND;
   4261 /// };
   4262 ///
   4263 /// It then replaces declaration of ND variable with:
   4264 /// struct __Block_byref_ND ND = {__isa=0B, __forwarding=&ND, __flags=some_flag,
   4265 ///                               __size=sizeof(struct __Block_byref_ND),
   4266 ///                               ND=initializer-if-any};
   4267 ///
   4268 ///
   4269 void RewriteObjC::RewriteByRefVar(VarDecl *ND) {
   4270   // Insert declaration for the function in which block literal is
   4271   // used.
   4272   if (CurFunctionDeclToDeclareForBlock)
   4273     RewriteBlockLiteralFunctionDecl(CurFunctionDeclToDeclareForBlock);
   4274   int flag = 0;
   4275   int isa = 0;
   4276   SourceLocation DeclLoc = ND->getTypeSpecStartLoc();
   4277   if (DeclLoc.isInvalid())
   4278     // If type location is missing, it is because of missing type (a warning).
   4279     // Use variable's location which is good for this case.
   4280     DeclLoc = ND->getLocation();
   4281   const char *startBuf = SM->getCharacterData(DeclLoc);
   4282   SourceLocation X = ND->getLocEnd();
   4283   X = SM->getExpansionLoc(X);
   4284   const char *endBuf = SM->getCharacterData(X);
   4285   std::string Name(ND->getNameAsString());
   4286   std::string ByrefType;
   4287   RewriteByRefString(ByrefType, Name, ND, true);
   4288   ByrefType += " {\n";
   4289   ByrefType += "  void *__isa;\n";
   4290   RewriteByRefString(ByrefType, Name, ND);
   4291   ByrefType += " *__forwarding;\n";
   4292   ByrefType += " int __flags;\n";
   4293   ByrefType += " int __size;\n";
   4294   // Add void *__Block_byref_id_object_copy;
   4295   // void *__Block_byref_id_object_dispose; if needed.
   4296   QualType Ty = ND->getType();
   4297   bool HasCopyAndDispose = Context->BlockRequiresCopying(Ty, ND);
   4298   if (HasCopyAndDispose) {
   4299     ByrefType += " void (*__Block_byref_id_object_copy)(void*, void*);\n";
   4300     ByrefType += " void (*__Block_byref_id_object_dispose)(void*);\n";
   4301   }
   4302 
   4303   QualType T = Ty;
   4304   (void)convertBlockPointerToFunctionPointer(T);
   4305   T.getAsStringInternal(Name, Context->getPrintingPolicy());
   4306 
   4307   ByrefType += " " + Name + ";\n";
   4308   ByrefType += "};\n";
   4309   // Insert this type in global scope. It is needed by helper function.
   4310   SourceLocation FunLocStart;
   4311   if (CurFunctionDef)
   4312      FunLocStart = CurFunctionDef->getTypeSpecStartLoc();
   4313   else {
   4314     assert(CurMethodDef && "RewriteByRefVar - CurMethodDef is null");
   4315     FunLocStart = CurMethodDef->getLocStart();
   4316   }
   4317   InsertText(FunLocStart, ByrefType);
   4318   if (Ty.isObjCGCWeak()) {
   4319     flag |= BLOCK_FIELD_IS_WEAK;
   4320     isa = 1;
   4321   }
   4322 
   4323   if (HasCopyAndDispose) {
   4324     flag = BLOCK_BYREF_CALLER;
   4325     QualType Ty = ND->getType();
   4326     // FIXME. Handle __weak variable (BLOCK_FIELD_IS_WEAK) as well.
   4327     if (Ty->isBlockPointerType())
   4328       flag |= BLOCK_FIELD_IS_BLOCK;
   4329     else
   4330       flag |= BLOCK_FIELD_IS_OBJECT;
   4331     std::string HF = SynthesizeByrefCopyDestroyHelper(ND, flag);
   4332     if (!HF.empty())
   4333       InsertText(FunLocStart, HF);
   4334   }
   4335 
   4336   // struct __Block_byref_ND ND =
   4337   // {0, &ND, some_flag, __size=sizeof(struct __Block_byref_ND),
   4338   //  initializer-if-any};
   4339   bool hasInit = (ND->getInit() != 0);
   4340   unsigned flags = 0;
   4341   if (HasCopyAndDispose)
   4342     flags |= BLOCK_HAS_COPY_DISPOSE;
   4343   Name = ND->getNameAsString();
   4344   ByrefType.clear();
   4345   RewriteByRefString(ByrefType, Name, ND);
   4346   std::string ForwardingCastType("(");
   4347   ForwardingCastType += ByrefType + " *)";
   4348   if (!hasInit) {
   4349     ByrefType += " " + Name + " = {(void*)";
   4350     ByrefType += utostr(isa);
   4351     ByrefType += "," +  ForwardingCastType + "&" + Name + ", ";
   4352     ByrefType += utostr(flags);
   4353     ByrefType += ", ";
   4354     ByrefType += "sizeof(";
   4355     RewriteByRefString(ByrefType, Name, ND);
   4356     ByrefType += ")";
   4357     if (HasCopyAndDispose) {
   4358       ByrefType += ", __Block_byref_id_object_copy_";
   4359       ByrefType += utostr(flag);
   4360       ByrefType += ", __Block_byref_id_object_dispose_";
   4361       ByrefType += utostr(flag);
   4362     }
   4363     ByrefType += "};\n";
   4364     unsigned nameSize = Name.size();
   4365     // for block or function pointer declaration. Name is aleady
   4366     // part of the declaration.
   4367     if (Ty->isBlockPointerType() || Ty->isFunctionPointerType())
   4368       nameSize = 1;
   4369     ReplaceText(DeclLoc, endBuf-startBuf+nameSize, ByrefType);
   4370   }
   4371   else {
   4372     SourceLocation startLoc;
   4373     Expr *E = ND->getInit();
   4374     if (const CStyleCastExpr *ECE = dyn_cast<CStyleCastExpr>(E))
   4375       startLoc = ECE->getLParenLoc();
   4376     else
   4377       startLoc = E->getLocStart();
   4378     startLoc = SM->getExpansionLoc(startLoc);
   4379     endBuf = SM->getCharacterData(startLoc);
   4380     ByrefType += " " + Name;
   4381     ByrefType += " = {(void*)";
   4382     ByrefType += utostr(isa);
   4383     ByrefType += "," +  ForwardingCastType + "&" + Name + ", ";
   4384     ByrefType += utostr(flags);
   4385     ByrefType += ", ";
   4386     ByrefType += "sizeof(";
   4387     RewriteByRefString(ByrefType, Name, ND);
   4388     ByrefType += "), ";
   4389     if (HasCopyAndDispose) {
   4390       ByrefType += "__Block_byref_id_object_copy_";
   4391       ByrefType += utostr(flag);
   4392       ByrefType += ", __Block_byref_id_object_dispose_";
   4393       ByrefType += utostr(flag);
   4394       ByrefType += ", ";
   4395     }
   4396     ReplaceText(DeclLoc, endBuf-startBuf, ByrefType);
   4397 
   4398     // Complete the newly synthesized compound expression by inserting a right
   4399     // curly brace before the end of the declaration.
   4400     // FIXME: This approach avoids rewriting the initializer expression. It
   4401     // also assumes there is only one declarator. For example, the following
   4402     // isn't currently supported by this routine (in general):
   4403     //
   4404     // double __block BYREFVAR = 1.34, BYREFVAR2 = 1.37;
   4405     //
   4406     const char *startInitializerBuf = SM->getCharacterData(startLoc);
   4407     const char *semiBuf = strchr(startInitializerBuf, ';');
   4408     assert((*semiBuf == ';') && "RewriteByRefVar: can't find ';'");
   4409     SourceLocation semiLoc =
   4410       startLoc.getLocWithOffset(semiBuf-startInitializerBuf);
   4411 
   4412     InsertText(semiLoc, "}");
   4413   }
   4414   return;
   4415 }
   4416 
   4417 void RewriteObjC::CollectBlockDeclRefInfo(BlockExpr *Exp) {
   4418   // Add initializers for any closure decl refs.
   4419   GetBlockDeclRefExprs(Exp->getBody());
   4420   if (BlockDeclRefs.size()) {
   4421     // Unique all "by copy" declarations.
   4422     for (unsigned i = 0; i < BlockDeclRefs.size(); i++)
   4423       if (!BlockDeclRefs[i]->getDecl()->hasAttr<BlocksAttr>()) {
   4424         if (!BlockByCopyDeclsPtrSet.count(BlockDeclRefs[i]->getDecl())) {
   4425           BlockByCopyDeclsPtrSet.insert(BlockDeclRefs[i]->getDecl());
   4426           BlockByCopyDecls.push_back(BlockDeclRefs[i]->getDecl());
   4427         }
   4428       }
   4429     // Unique all "by ref" declarations.
   4430     for (unsigned i = 0; i < BlockDeclRefs.size(); i++)
   4431       if (BlockDeclRefs[i]->getDecl()->hasAttr<BlocksAttr>()) {
   4432         if (!BlockByRefDeclsPtrSet.count(BlockDeclRefs[i]->getDecl())) {
   4433           BlockByRefDeclsPtrSet.insert(BlockDeclRefs[i]->getDecl());
   4434           BlockByRefDecls.push_back(BlockDeclRefs[i]->getDecl());
   4435         }
   4436       }
   4437     // Find any imported blocks...they will need special attention.
   4438     for (unsigned i = 0; i < BlockDeclRefs.size(); i++)
   4439       if (BlockDeclRefs[i]->getDecl()->hasAttr<BlocksAttr>() ||
   4440           BlockDeclRefs[i]->getType()->isObjCObjectPointerType() ||
   4441           BlockDeclRefs[i]->getType()->isBlockPointerType())
   4442         ImportedBlockDecls.insert(BlockDeclRefs[i]->getDecl());
   4443   }
   4444 }
   4445 
   4446 FunctionDecl *RewriteObjC::SynthBlockInitFunctionDecl(StringRef name) {
   4447   IdentifierInfo *ID = &Context->Idents.get(name);
   4448   QualType FType = Context->getFunctionNoProtoType(Context->VoidPtrTy);
   4449   return FunctionDecl::Create(*Context, TUDecl, SourceLocation(),
   4450                               SourceLocation(), ID, FType, 0, SC_Extern,
   4451                               false, false);
   4452 }
   4453 
   4454 Stmt *RewriteObjC::SynthBlockInitExpr(BlockExpr *Exp,
   4455                      const SmallVectorImpl<DeclRefExpr *> &InnerBlockDeclRefs) {
   4456   const BlockDecl *block = Exp->getBlockDecl();
   4457   Blocks.push_back(Exp);
   4458 
   4459   CollectBlockDeclRefInfo(Exp);
   4460 
   4461   // Add inner imported variables now used in current block.
   4462  int countOfInnerDecls = 0;
   4463   if (!InnerBlockDeclRefs.empty()) {
   4464     for (unsigned i = 0; i < InnerBlockDeclRefs.size(); i++) {
   4465       DeclRefExpr *Exp = InnerBlockDeclRefs[i];
   4466       ValueDecl *VD = Exp->getDecl();
   4467       if (!VD->hasAttr<BlocksAttr>() && !BlockByCopyDeclsPtrSet.count(VD)) {
   4468       // We need to save the copied-in variables in nested
   4469       // blocks because it is needed at the end for some of the API generations.
   4470       // See SynthesizeBlockLiterals routine.
   4471         InnerDeclRefs.push_back(Exp); countOfInnerDecls++;
   4472         BlockDeclRefs.push_back(Exp);
   4473         BlockByCopyDeclsPtrSet.insert(VD);
   4474         BlockByCopyDecls.push_back(VD);
   4475       }
   4476       if (VD->hasAttr<BlocksAttr>() && !BlockByRefDeclsPtrSet.count(VD)) {
   4477         InnerDeclRefs.push_back(Exp); countOfInnerDecls++;
   4478         BlockDeclRefs.push_back(Exp);
   4479         BlockByRefDeclsPtrSet.insert(VD);
   4480         BlockByRefDecls.push_back(VD);
   4481       }
   4482     }
   4483     // Find any imported blocks...they will need special attention.
   4484     for (unsigned i = 0; i < InnerBlockDeclRefs.size(); i++)
   4485       if (InnerBlockDeclRefs[i]->getDecl()->hasAttr<BlocksAttr>() ||
   4486           InnerBlockDeclRefs[i]->getType()->isObjCObjectPointerType() ||
   4487           InnerBlockDeclRefs[i]->getType()->isBlockPointerType())
   4488         ImportedBlockDecls.insert(InnerBlockDeclRefs[i]->getDecl());
   4489   }
   4490   InnerDeclRefsCount.push_back(countOfInnerDecls);
   4491 
   4492   std::string FuncName;
   4493 
   4494   if (CurFunctionDef)
   4495     FuncName = CurFunctionDef->getNameAsString();
   4496   else if (CurMethodDef)
   4497     BuildUniqueMethodName(FuncName, CurMethodDef);
   4498   else if (GlobalVarDecl)
   4499     FuncName = std::string(GlobalVarDecl->getNameAsString());
   4500 
   4501   std::string BlockNumber = utostr(Blocks.size()-1);
   4502 
   4503   std::string Tag = "__" + FuncName + "_block_impl_" + BlockNumber;
   4504   std::string Func = "__" + FuncName + "_block_func_" + BlockNumber;
   4505 
   4506   // Get a pointer to the function type so we can cast appropriately.
   4507   QualType BFT = convertFunctionTypeOfBlocks(Exp->getFunctionType());
   4508   QualType FType = Context->getPointerType(BFT);
   4509 
   4510   FunctionDecl *FD;
   4511   Expr *NewRep;
   4512 
   4513   // Simulate a contructor call...
   4514   FD = SynthBlockInitFunctionDecl(Tag);
   4515   DeclRefExpr *DRE = new (Context) DeclRefExpr(FD, false, FType, VK_RValue,
   4516                                                SourceLocation());
   4517 
   4518   SmallVector<Expr*, 4> InitExprs;
   4519 
   4520   // Initialize the block function.
   4521   FD = SynthBlockInitFunctionDecl(Func);
   4522   DeclRefExpr *Arg = new (Context) DeclRefExpr(FD, false, FD->getType(),
   4523                                                VK_LValue, SourceLocation());
   4524   CastExpr *castExpr = NoTypeInfoCStyleCastExpr(Context, Context->VoidPtrTy,
   4525                                                 CK_BitCast, Arg);
   4526   InitExprs.push_back(castExpr);
   4527 
   4528   // Initialize the block descriptor.
   4529   std::string DescData = "__" + FuncName + "_block_desc_" + BlockNumber + "_DATA";
   4530 
   4531   VarDecl *NewVD = VarDecl::Create(*Context, TUDecl,
   4532                                    SourceLocation(), SourceLocation(),
   4533                                    &Context->Idents.get(DescData.c_str()),
   4534                                    Context->VoidPtrTy, 0,
   4535                                    SC_Static);
   4536   UnaryOperator *DescRefExpr =
   4537     new (Context) UnaryOperator(new (Context) DeclRefExpr(NewVD, false,
   4538                                                           Context->VoidPtrTy,
   4539                                                           VK_LValue,
   4540                                                           SourceLocation()),
   4541                                 UO_AddrOf,
   4542                                 Context->getPointerType(Context->VoidPtrTy),
   4543                                 VK_RValue, OK_Ordinary,
   4544                                 SourceLocation());
   4545   InitExprs.push_back(DescRefExpr);
   4546 
   4547   // Add initializers for any closure decl refs.
   4548   if (BlockDeclRefs.size()) {
   4549     Expr *Exp;
   4550     // Output all "by copy" declarations.
   4551     for (SmallVectorImpl<ValueDecl *>::iterator I = BlockByCopyDecls.begin(),
   4552          E = BlockByCopyDecls.end(); I != E; ++I) {
   4553       if (isObjCType((*I)->getType())) {
   4554         // FIXME: Conform to ABI ([[obj retain] autorelease]).
   4555         FD = SynthBlockInitFunctionDecl((*I)->getName());
   4556         Exp = new (Context) DeclRefExpr(FD, false, FD->getType(), VK_LValue,
   4557                                         SourceLocation());
   4558         if (HasLocalVariableExternalStorage(*I)) {
   4559           QualType QT = (*I)->getType();
   4560           QT = Context->getPointerType(QT);
   4561           Exp = new (Context) UnaryOperator(Exp, UO_AddrOf, QT, VK_RValue,
   4562                                             OK_Ordinary, SourceLocation());
   4563         }
   4564       } else if (isTopLevelBlockPointerType((*I)->getType())) {
   4565         FD = SynthBlockInitFunctionDecl((*I)->getName());
   4566         Arg = new (Context) DeclRefExpr(FD, false, FD->getType(), VK_LValue,
   4567                                         SourceLocation());
   4568         Exp = NoTypeInfoCStyleCastExpr(Context, Context->VoidPtrTy,
   4569                                        CK_BitCast, Arg);
   4570       } else {
   4571         FD = SynthBlockInitFunctionDecl((*I)->getName());
   4572         Exp = new (Context) DeclRefExpr(FD, false, FD->getType(), VK_LValue,
   4573                                         SourceLocation());
   4574         if (HasLocalVariableExternalStorage(*I)) {
   4575           QualType QT = (*I)->getType();
   4576           QT = Context->getPointerType(QT);
   4577           Exp = new (Context) UnaryOperator(Exp, UO_AddrOf, QT, VK_RValue,
   4578                                             OK_Ordinary, SourceLocation());
   4579         }
   4580 
   4581       }
   4582       InitExprs.push_back(Exp);
   4583     }
   4584     // Output all "by ref" declarations.
   4585     for (SmallVectorImpl<ValueDecl *>::iterator I = BlockByRefDecls.begin(),
   4586          E = BlockByRefDecls.end(); I != E; ++I) {
   4587       ValueDecl *ND = (*I);
   4588       std::string Name(ND->getNameAsString());
   4589       std::string RecName;
   4590       RewriteByRefString(RecName, Name, ND, true);
   4591       IdentifierInfo *II = &Context->Idents.get(RecName.c_str()
   4592                                                 + sizeof("struct"));
   4593       RecordDecl *RD = RecordDecl::Create(*Context, TTK_Struct, TUDecl,
   4594                                           SourceLocation(), SourceLocation(),
   4595                                           II);
   4596       assert(RD && "SynthBlockInitExpr(): Can't find RecordDecl");
   4597       QualType castT = Context->getPointerType(Context->getTagDeclType(RD));
   4598 
   4599       FD = SynthBlockInitFunctionDecl((*I)->getName());
   4600       Exp = new (Context) DeclRefExpr(FD, false, FD->getType(), VK_LValue,
   4601                                       SourceLocation());
   4602       bool isNestedCapturedVar = false;
   4603       if (block)
   4604         for (BlockDecl::capture_const_iterator ci = block->capture_begin(),
   4605              ce = block->capture_end(); ci != ce; ++ci) {
   4606           const VarDecl *variable = ci->getVariable();
   4607           if (variable == ND && ci->isNested()) {
   4608             assert (ci->isByRef() &&
   4609                     "SynthBlockInitExpr - captured block variable is not byref");
   4610             isNestedCapturedVar = true;
   4611             break;
   4612           }
   4613         }
   4614       // captured nested byref variable has its address passed. Do not take
   4615       // its address again.
   4616       if (!isNestedCapturedVar)
   4617           Exp = new (Context) UnaryOperator(Exp, UO_AddrOf,
   4618                                      Context->getPointerType(Exp->getType()),
   4619                                      VK_RValue, OK_Ordinary, SourceLocation());
   4620       Exp = NoTypeInfoCStyleCastExpr(Context, castT, CK_BitCast, Exp);
   4621       InitExprs.push_back(Exp);
   4622     }
   4623   }
   4624   if (ImportedBlockDecls.size()) {
   4625     // generate BLOCK_HAS_COPY_DISPOSE(have helper funcs) | BLOCK_HAS_DESCRIPTOR
   4626     int flag = (BLOCK_HAS_COPY_DISPOSE | BLOCK_HAS_DESCRIPTOR);
   4627     unsigned IntSize =
   4628       static_cast<unsigned>(Context->getTypeSize(Context->IntTy));
   4629     Expr *FlagExp = IntegerLiteral::Create(*Context, llvm::APInt(IntSize, flag),
   4630                                            Context->IntTy, SourceLocation());
   4631     InitExprs.push_back(FlagExp);
   4632   }
   4633   NewRep = new (Context) CallExpr(*Context, DRE, InitExprs,
   4634                                   FType, VK_LValue, SourceLocation());
   4635   NewRep = new (Context) UnaryOperator(NewRep, UO_AddrOf,
   4636                              Context->getPointerType(NewRep->getType()),
   4637                              VK_RValue, OK_Ordinary, SourceLocation());
   4638   NewRep = NoTypeInfoCStyleCastExpr(Context, FType, CK_BitCast,
   4639                                     NewRep);
   4640   BlockDeclRefs.clear();
   4641   BlockByRefDecls.clear();
   4642   BlockByRefDeclsPtrSet.clear();
   4643   BlockByCopyDecls.clear();
   4644   BlockByCopyDeclsPtrSet.clear();
   4645   ImportedBlockDecls.clear();
   4646   return NewRep;
   4647 }
   4648 
   4649 bool RewriteObjC::IsDeclStmtInForeachHeader(DeclStmt *DS) {
   4650   if (const ObjCForCollectionStmt * CS =
   4651       dyn_cast<ObjCForCollectionStmt>(Stmts.back()))
   4652         return CS->getElement() == DS;
   4653   return false;
   4654 }
   4655 
   4656 //===----------------------------------------------------------------------===//
   4657 // Function Body / Expression rewriting
   4658 //===----------------------------------------------------------------------===//
   4659 
   4660 Stmt *RewriteObjC::RewriteFunctionBodyOrGlobalInitializer(Stmt *S) {
   4661   if (isa<SwitchStmt>(S) || isa<WhileStmt>(S) ||
   4662       isa<DoStmt>(S) || isa<ForStmt>(S))
   4663     Stmts.push_back(S);
   4664   else if (isa<ObjCForCollectionStmt>(S)) {
   4665     Stmts.push_back(S);
   4666     ObjCBcLabelNo.push_back(++BcLabelCount);
   4667   }
   4668 
   4669   // Pseudo-object operations and ivar references need special
   4670   // treatment because we're going to recursively rewrite them.
   4671   if (PseudoObjectExpr *PseudoOp = dyn_cast<PseudoObjectExpr>(S)) {
   4672     if (isa<BinaryOperator>(PseudoOp->getSyntacticForm())) {
   4673       return RewritePropertyOrImplicitSetter(PseudoOp);
   4674     } else {
   4675       return RewritePropertyOrImplicitGetter(PseudoOp);
   4676     }
   4677   } else if (ObjCIvarRefExpr *IvarRefExpr = dyn_cast<ObjCIvarRefExpr>(S)) {
   4678     return RewriteObjCIvarRefExpr(IvarRefExpr);
   4679   }
   4680 
   4681   SourceRange OrigStmtRange = S->getSourceRange();
   4682 
   4683   // Perform a bottom up rewrite of all children.
   4684   for (Stmt::child_range CI = S->children(); CI; ++CI)
   4685     if (*CI) {
   4686       Stmt *childStmt = (*CI);
   4687       Stmt *newStmt = RewriteFunctionBodyOrGlobalInitializer(childStmt);
   4688       if (newStmt) {
   4689         *CI = newStmt;
   4690       }
   4691     }
   4692 
   4693   if (BlockExpr *BE = dyn_cast<BlockExpr>(S)) {
   4694     SmallVector<DeclRefExpr *, 8> InnerBlockDeclRefs;
   4695     llvm::SmallPtrSet<const DeclContext *, 8> InnerContexts;
   4696     InnerContexts.insert(BE->getBlockDecl());
   4697     ImportedLocalExternalDecls.clear();
   4698     GetInnerBlockDeclRefExprs(BE->getBody(),
   4699                               InnerBlockDeclRefs, InnerContexts);
   4700     // Rewrite the block body in place.
   4701     Stmt *SaveCurrentBody = CurrentBody;
   4702     CurrentBody = BE->getBody();
   4703     PropParentMap = 0;
   4704     // block literal on rhs of a property-dot-sytax assignment
   4705     // must be replaced by its synthesize ast so getRewrittenText
   4706     // works as expected. In this case, what actually ends up on RHS
   4707     // is the blockTranscribed which is the helper function for the
   4708     // block literal; as in: self.c = ^() {[ace ARR];};
   4709     bool saveDisableReplaceStmt = DisableReplaceStmt;
   4710     DisableReplaceStmt = false;
   4711     RewriteFunctionBodyOrGlobalInitializer(BE->getBody());
   4712     DisableReplaceStmt = saveDisableReplaceStmt;
   4713     CurrentBody = SaveCurrentBody;
   4714     PropParentMap = 0;
   4715     ImportedLocalExternalDecls.clear();
   4716     // Now we snarf the rewritten text and stash it away for later use.
   4717     std::string Str = Rewrite.getRewrittenText(BE->getSourceRange());
   4718     RewrittenBlockExprs[BE] = Str;
   4719 
   4720     Stmt *blockTranscribed = SynthBlockInitExpr(BE, InnerBlockDeclRefs);
   4721 
   4722     //blockTranscribed->dump();
   4723     ReplaceStmt(S, blockTranscribed);
   4724     return blockTranscribed;
   4725   }
   4726   // Handle specific things.
   4727   if (ObjCEncodeExpr *AtEncode = dyn_cast<ObjCEncodeExpr>(S))
   4728     return RewriteAtEncode(AtEncode);
   4729 
   4730   if (ObjCSelectorExpr *AtSelector = dyn_cast<ObjCSelectorExpr>(S))
   4731     return RewriteAtSelector(AtSelector);
   4732 
   4733   if (ObjCStringLiteral *AtString = dyn_cast<ObjCStringLiteral>(S))
   4734     return RewriteObjCStringLiteral(AtString);
   4735 
   4736   if (ObjCMessageExpr *MessExpr = dyn_cast<ObjCMessageExpr>(S)) {
   4737 #if 0
   4738     // Before we rewrite it, put the original message expression in a comment.
   4739     SourceLocation startLoc = MessExpr->getLocStart();
   4740     SourceLocation endLoc = MessExpr->getLocEnd();
   4741 
   4742     const char *startBuf = SM->getCharacterData(startLoc);
   4743     const char *endBuf = SM->getCharacterData(endLoc);
   4744 
   4745     std::string messString;
   4746     messString += "// ";
   4747     messString.append(startBuf, endBuf-startBuf+1);
   4748     messString += "\n";
   4749 
   4750     // FIXME: Missing definition of
   4751     // InsertText(clang::SourceLocation, char const*, unsigned int).
   4752     // InsertText(startLoc, messString.c_str(), messString.size());
   4753     // Tried this, but it didn't work either...
   4754     // ReplaceText(startLoc, 0, messString.c_str(), messString.size());
   4755 #endif
   4756     return RewriteMessageExpr(MessExpr);
   4757   }
   4758 
   4759   if (ObjCAtTryStmt *StmtTry = dyn_cast<ObjCAtTryStmt>(S))
   4760     return RewriteObjCTryStmt(StmtTry);
   4761 
   4762   if (ObjCAtSynchronizedStmt *StmtTry = dyn_cast<ObjCAtSynchronizedStmt>(S))
   4763     return RewriteObjCSynchronizedStmt(StmtTry);
   4764 
   4765   if (ObjCAtThrowStmt *StmtThrow = dyn_cast<ObjCAtThrowStmt>(S))
   4766     return RewriteObjCThrowStmt(StmtThrow);
   4767 
   4768   if (ObjCProtocolExpr *ProtocolExp = dyn_cast<ObjCProtocolExpr>(S))
   4769     return RewriteObjCProtocolExpr(ProtocolExp);
   4770 
   4771   if (ObjCForCollectionStmt *StmtForCollection =
   4772         dyn_cast<ObjCForCollectionStmt>(S))
   4773     return RewriteObjCForCollectionStmt(StmtForCollection,
   4774                                         OrigStmtRange.getEnd());
   4775   if (BreakStmt *StmtBreakStmt =
   4776       dyn_cast<BreakStmt>(S))
   4777     return RewriteBreakStmt(StmtBreakStmt);
   4778   if (ContinueStmt *StmtContinueStmt =
   4779       dyn_cast<ContinueStmt>(S))
   4780     return RewriteContinueStmt(StmtContinueStmt);
   4781 
   4782   // Need to check for protocol refs (id <P>, Foo <P> *) in variable decls
   4783   // and cast exprs.
   4784   if (DeclStmt *DS = dyn_cast<DeclStmt>(S)) {
   4785     // FIXME: What we're doing here is modifying the type-specifier that
   4786     // precedes the first Decl.  In the future the DeclGroup should have
   4787     // a separate type-specifier that we can rewrite.
   4788     // NOTE: We need to avoid rewriting the DeclStmt if it is within
   4789     // the context of an ObjCForCollectionStmt. For example:
   4790     //   NSArray *someArray;
   4791     //   for (id <FooProtocol> index in someArray) ;
   4792     // This is because RewriteObjCForCollectionStmt() does textual rewriting
   4793     // and it depends on the original text locations/positions.
   4794     if (Stmts.empty() || !IsDeclStmtInForeachHeader(DS))
   4795       RewriteObjCQualifiedInterfaceTypes(*DS->decl_begin());
   4796 
   4797     // Blocks rewrite rules.
   4798     for (DeclStmt::decl_iterator DI = DS->decl_begin(), DE = DS->decl_end();
   4799          DI != DE; ++DI) {
   4800       Decl *SD = *DI;
   4801       if (ValueDecl *ND = dyn_cast<ValueDecl>(SD)) {
   4802         if (isTopLevelBlockPointerType(ND->getType()))
   4803           RewriteBlockPointerDecl(ND);
   4804         else if (ND->getType()->isFunctionPointerType())
   4805           CheckFunctionPointerDecl(ND->getType(), ND);
   4806         if (VarDecl *VD = dyn_cast<VarDecl>(SD)) {
   4807           if (VD->hasAttr<BlocksAttr>()) {
   4808             static unsigned uniqueByrefDeclCount = 0;
   4809             assert(!BlockByRefDeclNo.count(ND) &&
   4810               "RewriteFunctionBodyOrGlobalInitializer: Duplicate byref decl");
   4811             BlockByRefDeclNo[ND] = uniqueByrefDeclCount++;
   4812             RewriteByRefVar(VD);
   4813           }
   4814           else
   4815             RewriteTypeOfDecl(VD);
   4816         }
   4817       }
   4818       if (TypedefNameDecl *TD = dyn_cast<TypedefNameDecl>(SD)) {
   4819         if (isTopLevelBlockPointerType(TD->getUnderlyingType()))
   4820           RewriteBlockPointerDecl(TD);
   4821         else if (TD->getUnderlyingType()->isFunctionPointerType())
   4822           CheckFunctionPointerDecl(TD->getUnderlyingType(), TD);
   4823       }
   4824     }
   4825   }
   4826 
   4827   if (CStyleCastExpr *CE = dyn_cast<CStyleCastExpr>(S))
   4828     RewriteObjCQualifiedInterfaceTypes(CE);
   4829 
   4830   if (isa<SwitchStmt>(S) || isa<WhileStmt>(S) ||
   4831       isa<DoStmt>(S) || isa<ForStmt>(S)) {
   4832     assert(!Stmts.empty() && "Statement stack is empty");
   4833     assert ((isa<SwitchStmt>(Stmts.back()) || isa<WhileStmt>(Stmts.back()) ||
   4834              isa<DoStmt>(Stmts.back()) || isa<ForStmt>(Stmts.back()))
   4835             && "Statement stack mismatch");
   4836     Stmts.pop_back();
   4837   }
   4838   // Handle blocks rewriting.
   4839   if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(S)) {
   4840     ValueDecl *VD = DRE->getDecl();
   4841     if (VD->hasAttr<BlocksAttr>())
   4842       return RewriteBlockDeclRefExpr(DRE);
   4843     if (HasLocalVariableExternalStorage(VD))
   4844       return RewriteLocalVariableExternalStorage(DRE);
   4845   }
   4846 
   4847   if (CallExpr *CE = dyn_cast<CallExpr>(S)) {
   4848     if (CE->getCallee()->getType()->isBlockPointerType()) {
   4849       Stmt *BlockCall = SynthesizeBlockCall(CE, CE->getCallee());
   4850       ReplaceStmt(S, BlockCall);
   4851       return BlockCall;
   4852     }
   4853   }
   4854   if (CStyleCastExpr *CE = dyn_cast<CStyleCastExpr>(S)) {
   4855     RewriteCastExpr(CE);
   4856   }
   4857 #if 0
   4858   if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(S)) {
   4859     CastExpr *Replacement = new (Context) CastExpr(ICE->getType(),
   4860                                                    ICE->getSubExpr(),
   4861                                                    SourceLocation());
   4862     // Get the new text.
   4863     std::string SStr;
   4864     llvm::raw_string_ostream Buf(SStr);
   4865     Replacement->printPretty(Buf);
   4866     const std::string &Str = Buf.str();
   4867 
   4868     printf("CAST = %s\n", &Str[0]);
   4869     InsertText(ICE->getSubExpr()->getLocStart(), &Str[0], Str.size());
   4870     delete S;
   4871     return Replacement;
   4872   }
   4873 #endif
   4874   // Return this stmt unmodified.
   4875   return S;
   4876 }
   4877 
   4878 void RewriteObjC::RewriteRecordBody(RecordDecl *RD) {
   4879   for (RecordDecl::field_iterator i = RD->field_begin(),
   4880                                   e = RD->field_end(); i != e; ++i) {
   4881     FieldDecl *FD = *i;
   4882     if (isTopLevelBlockPointerType(FD->getType()))
   4883       RewriteBlockPointerDecl(FD);
   4884     if (FD->getType()->isObjCQualifiedIdType() ||
   4885         FD->getType()->isObjCQualifiedInterfaceType())
   4886       RewriteObjCQualifiedInterfaceTypes(FD);
   4887   }
   4888 }
   4889 
   4890 /// HandleDeclInMainFile - This is called for each top-level decl defined in the
   4891 /// main file of the input.
   4892 void RewriteObjC::HandleDeclInMainFile(Decl *D) {
   4893   switch (D->getKind()) {
   4894     case Decl::Function: {
   4895       FunctionDecl *FD = cast<FunctionDecl>(D);
   4896       if (FD->isOverloadedOperator())
   4897         return;
   4898 
   4899       // Since function prototypes don't have ParmDecl's, we check the function
   4900       // prototype. This enables us to rewrite function declarations and
   4901       // definitions using the same code.
   4902       RewriteBlocksInFunctionProtoType(FD->getType(), FD);
   4903 
   4904       if (!FD->isThisDeclarationADefinition())
   4905         break;
   4906 
   4907       // FIXME: If this should support Obj-C++, support CXXTryStmt
   4908       if (CompoundStmt *Body = dyn_cast_or_null<CompoundStmt>(FD->getBody())) {
   4909         CurFunctionDef = FD;
   4910         CurFunctionDeclToDeclareForBlock = FD;
   4911         CurrentBody = Body;
   4912         Body =
   4913         cast_or_null<CompoundStmt>(RewriteFunctionBodyOrGlobalInitializer(Body));
   4914         FD->setBody(Body);
   4915         CurrentBody = 0;
   4916         if (PropParentMap) {
   4917           delete PropParentMap;
   4918           PropParentMap = 0;
   4919         }
   4920         // This synthesizes and inserts the block "impl" struct, invoke function,
   4921         // and any copy/dispose helper functions.
   4922         InsertBlockLiteralsWithinFunction(FD);
   4923         CurFunctionDef = 0;
   4924         CurFunctionDeclToDeclareForBlock = 0;
   4925       }
   4926       break;
   4927     }
   4928     case Decl::ObjCMethod: {
   4929       ObjCMethodDecl *MD = cast<ObjCMethodDecl>(D);
   4930       if (CompoundStmt *Body = MD->getCompoundBody()) {
   4931         CurMethodDef = MD;
   4932         CurrentBody = Body;
   4933         Body =
   4934           cast_or_null<CompoundStmt>(RewriteFunctionBodyOrGlobalInitializer(Body));
   4935         MD->setBody(Body);
   4936         CurrentBody = 0;
   4937         if (PropParentMap) {
   4938           delete PropParentMap;
   4939           PropParentMap = 0;
   4940         }
   4941         InsertBlockLiteralsWithinMethod(MD);
   4942         CurMethodDef = 0;
   4943       }
   4944       break;
   4945     }
   4946     case Decl::ObjCImplementation: {
   4947       ObjCImplementationDecl *CI = cast<ObjCImplementationDecl>(D);
   4948       ClassImplementation.push_back(CI);
   4949       break;
   4950     }
   4951     case Decl::ObjCCategoryImpl: {
   4952       ObjCCategoryImplDecl *CI = cast<ObjCCategoryImplDecl>(D);
   4953       CategoryImplementation.push_back(CI);
   4954       break;
   4955     }
   4956     case Decl::Var: {
   4957       VarDecl *VD = cast<VarDecl>(D);
   4958       RewriteObjCQualifiedInterfaceTypes(VD);
   4959       if (isTopLevelBlockPointerType(VD->getType()))
   4960         RewriteBlockPointerDecl(VD);
   4961       else if (VD->getType()->isFunctionPointerType()) {
   4962         CheckFunctionPointerDecl(VD->getType(), VD);
   4963         if (VD->getInit()) {
   4964           if (CStyleCastExpr *CE = dyn_cast<CStyleCastExpr>(VD->getInit())) {
   4965             RewriteCastExpr(CE);
   4966           }
   4967         }
   4968       } else if (VD->getType()->isRecordType()) {
   4969         RecordDecl *RD = VD->getType()->getAs<RecordType>()->getDecl();
   4970         if (RD->isCompleteDefinition())
   4971           RewriteRecordBody(RD);
   4972       }
   4973       if (VD->getInit()) {
   4974         GlobalVarDecl = VD;
   4975         CurrentBody = VD->getInit();
   4976         RewriteFunctionBodyOrGlobalInitializer(VD->getInit());
   4977         CurrentBody = 0;
   4978         if (PropParentMap) {
   4979           delete PropParentMap;
   4980           PropParentMap = 0;
   4981         }
   4982         SynthesizeBlockLiterals(VD->getTypeSpecStartLoc(), VD->getName());
   4983         GlobalVarDecl = 0;
   4984 
   4985         // This is needed for blocks.
   4986         if (CStyleCastExpr *CE = dyn_cast<CStyleCastExpr>(VD->getInit())) {
   4987             RewriteCastExpr(CE);
   4988         }
   4989       }
   4990       break;
   4991     }
   4992     case Decl::TypeAlias:
   4993     case Decl::Typedef: {
   4994       if (TypedefNameDecl *TD = dyn_cast<TypedefNameDecl>(D)) {
   4995         if (isTopLevelBlockPointerType(TD->getUnderlyingType()))
   4996           RewriteBlockPointerDecl(TD);
   4997         else if (TD->getUnderlyingType()->isFunctionPointerType())
   4998           CheckFunctionPointerDecl(TD->getUnderlyingType(), TD);
   4999       }
   5000       break;
   5001     }
   5002     case Decl::CXXRecord:
   5003     case Decl::Record: {
   5004       RecordDecl *RD = cast<RecordDecl>(D);
   5005       if (RD->isCompleteDefinition())
   5006         RewriteRecordBody(RD);
   5007       break;
   5008     }
   5009     default:
   5010       break;
   5011   }
   5012   // Nothing yet.
   5013 }
   5014 
   5015 void RewriteObjC::HandleTranslationUnit(ASTContext &C) {
   5016   if (Diags.hasErrorOccurred())
   5017     return;
   5018 
   5019   RewriteInclude();
   5020 
   5021   // Here's a great place to add any extra declarations that may be needed.
   5022   // Write out meta data for each @protocol(<expr>).
   5023   for (llvm::SmallPtrSet<ObjCProtocolDecl *,8>::iterator I = ProtocolExprDecls.begin(),
   5024        E = ProtocolExprDecls.end(); I != E; ++I)
   5025     RewriteObjCProtocolMetaData(*I, "", "", Preamble);
   5026 
   5027   InsertText(SM->getLocForStartOfFile(MainFileID), Preamble, false);
   5028   if (ClassImplementation.size() || CategoryImplementation.size())
   5029     RewriteImplementations();
   5030 
   5031   // Get the buffer corresponding to MainFileID.  If we haven't changed it, then
   5032   // we are done.
   5033   if (const RewriteBuffer *RewriteBuf =
   5034       Rewrite.getRewriteBufferFor(MainFileID)) {
   5035     //printf("Changed:\n");
   5036     *OutFile << std::string(RewriteBuf->begin(), RewriteBuf->end());
   5037   } else {
   5038     llvm::errs() << "No changes\n";
   5039   }
   5040 
   5041   if (ClassImplementation.size() || CategoryImplementation.size() ||
   5042       ProtocolExprDecls.size()) {
   5043     // Rewrite Objective-c meta data*
   5044     std::string ResultStr;
   5045     RewriteMetaDataIntoBuffer(ResultStr);
   5046     // Emit metadata.
   5047     *OutFile << ResultStr;
   5048   }
   5049   OutFile->flush();
   5050 }
   5051 
   5052 void RewriteObjCFragileABI::Initialize(ASTContext &context) {
   5053   InitializeCommon(context);
   5054 
   5055   // declaring objc_selector outside the parameter list removes a silly
   5056   // scope related warning...
   5057   if (IsHeader)
   5058     Preamble = "#pragma once\n";
   5059   Preamble += "struct objc_selector; struct objc_class;\n";
   5060   Preamble += "struct __rw_objc_super { struct objc_object *object; ";
   5061   Preamble += "struct objc_object *superClass; ";
   5062   if (LangOpts.MicrosoftExt) {
   5063     // Add a constructor for creating temporary objects.
   5064     Preamble += "__rw_objc_super(struct objc_object *o, struct objc_object *s) "
   5065     ": ";
   5066     Preamble += "object(o), superClass(s) {} ";
   5067   }
   5068   Preamble += "};\n";
   5069   Preamble += "#ifndef _REWRITER_typedef_Protocol\n";
   5070   Preamble += "typedef struct objc_object Protocol;\n";
   5071   Preamble += "#define _REWRITER_typedef_Protocol\n";
   5072   Preamble += "#endif\n";
   5073   if (LangOpts.MicrosoftExt) {
   5074     Preamble += "#define __OBJC_RW_DLLIMPORT extern \"C\" __declspec(dllimport)\n";
   5075     Preamble += "#define __OBJC_RW_STATICIMPORT extern \"C\"\n";
   5076   } else
   5077     Preamble += "#define __OBJC_RW_DLLIMPORT extern\n";
   5078   Preamble += "__OBJC_RW_DLLIMPORT struct objc_object *objc_msgSend";
   5079   Preamble += "(struct objc_object *, struct objc_selector *, ...);\n";
   5080   Preamble += "__OBJC_RW_DLLIMPORT struct objc_object *objc_msgSendSuper";
   5081   Preamble += "(struct objc_super *, struct objc_selector *, ...);\n";
   5082   Preamble += "__OBJC_RW_DLLIMPORT struct objc_object* objc_msgSend_stret";
   5083   Preamble += "(struct objc_object *, struct objc_selector *, ...);\n";
   5084   Preamble += "__OBJC_RW_DLLIMPORT struct objc_object* objc_msgSendSuper_stret";
   5085   Preamble += "(struct objc_super *, struct objc_selector *, ...);\n";
   5086   Preamble += "__OBJC_RW_DLLIMPORT double objc_msgSend_fpret";
   5087   Preamble += "(struct objc_object *, struct objc_selector *, ...);\n";
   5088   Preamble += "__OBJC_RW_DLLIMPORT struct objc_object *objc_getClass";
   5089   Preamble += "(const char *);\n";
   5090   Preamble += "__OBJC_RW_DLLIMPORT struct objc_class *class_getSuperclass";
   5091   Preamble += "(struct objc_class *);\n";
   5092   Preamble += "__OBJC_RW_DLLIMPORT struct objc_object *objc_getMetaClass";
   5093   Preamble += "(const char *);\n";
   5094   Preamble += "__OBJC_RW_DLLIMPORT void objc_exception_throw(struct objc_object *);\n";
   5095   Preamble += "__OBJC_RW_DLLIMPORT void objc_exception_try_enter(void *);\n";
   5096   Preamble += "__OBJC_RW_DLLIMPORT void objc_exception_try_exit(void *);\n";
   5097   Preamble += "__OBJC_RW_DLLIMPORT struct objc_object *objc_exception_extract(void *);\n";
   5098   Preamble += "__OBJC_RW_DLLIMPORT int objc_exception_match";
   5099   Preamble += "(struct objc_class *, struct objc_object *);\n";
   5100   // @synchronized hooks.
   5101   Preamble += "__OBJC_RW_DLLIMPORT int objc_sync_enter(struct objc_object *);\n";
   5102   Preamble += "__OBJC_RW_DLLIMPORT int objc_sync_exit(struct objc_object *);\n";
   5103   Preamble += "__OBJC_RW_DLLIMPORT Protocol *objc_getProtocol(const char *);\n";
   5104   Preamble += "#ifndef __FASTENUMERATIONSTATE\n";
   5105   Preamble += "struct __objcFastEnumerationState {\n\t";
   5106   Preamble += "unsigned long state;\n\t";
   5107   Preamble += "void **itemsPtr;\n\t";
   5108   Preamble += "unsigned long *mutationsPtr;\n\t";
   5109   Preamble += "unsigned long extra[5];\n};\n";
   5110   Preamble += "__OBJC_RW_DLLIMPORT void objc_enumerationMutation(struct objc_object *);\n";
   5111   Preamble += "#define __FASTENUMERATIONSTATE\n";
   5112   Preamble += "#endif\n";
   5113   Preamble += "#ifndef __NSCONSTANTSTRINGIMPL\n";
   5114   Preamble += "struct __NSConstantStringImpl {\n";
   5115   Preamble += "  int *isa;\n";
   5116   Preamble += "  int flags;\n";
   5117   Preamble += "  char *str;\n";
   5118   Preamble += "  long length;\n";
   5119   Preamble += "};\n";
   5120   Preamble += "#ifdef CF_EXPORT_CONSTANT_STRING\n";
   5121   Preamble += "extern \"C\" __declspec(dllexport) int __CFConstantStringClassReference[];\n";
   5122   Preamble += "#else\n";
   5123   Preamble += "__OBJC_RW_DLLIMPORT int __CFConstantStringClassReference[];\n";
   5124   Preamble += "#endif\n";
   5125   Preamble += "#define __NSCONSTANTSTRINGIMPL\n";
   5126   Preamble += "#endif\n";
   5127   // Blocks preamble.
   5128   Preamble += "#ifndef BLOCK_IMPL\n";
   5129   Preamble += "#define BLOCK_IMPL\n";
   5130   Preamble += "struct __block_impl {\n";
   5131   Preamble += "  void *isa;\n";
   5132   Preamble += "  int Flags;\n";
   5133   Preamble += "  int Reserved;\n";
   5134   Preamble += "  void *FuncPtr;\n";
   5135   Preamble += "};\n";
   5136   Preamble += "// Runtime copy/destroy helper functions (from Block_private.h)\n";
   5137   Preamble += "#ifdef __OBJC_EXPORT_BLOCKS\n";
   5138   Preamble += "extern \"C\" __declspec(dllexport) "
   5139   "void _Block_object_assign(void *, const void *, const int);\n";
   5140   Preamble += "extern \"C\" __declspec(dllexport) void _Block_object_dispose(const void *, const int);\n";
   5141   Preamble += "extern \"C\" __declspec(dllexport) void *_NSConcreteGlobalBlock[32];\n";
   5142   Preamble += "extern \"C\" __declspec(dllexport) void *_NSConcreteStackBlock[32];\n";
   5143   Preamble += "#else\n";
   5144   Preamble += "__OBJC_RW_DLLIMPORT void _Block_object_assign(void *, const void *, const int);\n";
   5145   Preamble += "__OBJC_RW_DLLIMPORT void _Block_object_dispose(const void *, const int);\n";
   5146   Preamble += "__OBJC_RW_DLLIMPORT void *_NSConcreteGlobalBlock[32];\n";
   5147   Preamble += "__OBJC_RW_DLLIMPORT void *_NSConcreteStackBlock[32];\n";
   5148   Preamble += "#endif\n";
   5149   Preamble += "#endif\n";
   5150   if (LangOpts.MicrosoftExt) {
   5151     Preamble += "#undef __OBJC_RW_DLLIMPORT\n";
   5152     Preamble += "#undef __OBJC_RW_STATICIMPORT\n";
   5153     Preamble += "#ifndef KEEP_ATTRIBUTES\n";  // We use this for clang tests.
   5154     Preamble += "#define __attribute__(X)\n";
   5155     Preamble += "#endif\n";
   5156     Preamble += "#define __weak\n";
   5157   }
   5158   else {
   5159     Preamble += "#define __block\n";
   5160     Preamble += "#define __weak\n";
   5161   }
   5162   // NOTE! Windows uses LLP64 for 64bit mode. So, cast pointer to long long
   5163   // as this avoids warning in any 64bit/32bit compilation model.
   5164   Preamble += "\n#define __OFFSETOFIVAR__(TYPE, MEMBER) ((long long) &((TYPE *)0)->MEMBER)\n";
   5165 }
   5166 
   5167 /// RewriteIvarOffsetComputation - This rutine synthesizes computation of
   5168 /// ivar offset.
   5169 void RewriteObjCFragileABI::RewriteIvarOffsetComputation(ObjCIvarDecl *ivar,
   5170                                                          std::string &Result) {
   5171   if (ivar->isBitField()) {
   5172     // FIXME: The hack below doesn't work for bitfields. For now, we simply
   5173     // place all bitfields at offset 0.
   5174     Result += "0";
   5175   } else {
   5176     Result += "__OFFSETOFIVAR__(struct ";
   5177     Result += ivar->getContainingInterface()->getNameAsString();
   5178     if (LangOpts.MicrosoftExt)
   5179       Result += "_IMPL";
   5180     Result += ", ";
   5181     Result += ivar->getNameAsString();
   5182     Result += ")";
   5183   }
   5184 }
   5185 
   5186 /// RewriteObjCProtocolMetaData - Rewrite protocols meta-data.
   5187 void RewriteObjCFragileABI::RewriteObjCProtocolMetaData(
   5188                             ObjCProtocolDecl *PDecl, StringRef prefix,
   5189                             StringRef ClassName, std::string &Result) {
   5190   static bool objc_protocol_methods = false;
   5191 
   5192   // Output struct protocol_methods holder of method selector and type.
   5193   if (!objc_protocol_methods && PDecl->hasDefinition()) {
   5194     /* struct protocol_methods {
   5195      SEL _cmd;
   5196      char *method_types;
   5197      }
   5198      */
   5199     Result += "\nstruct _protocol_methods {\n";
   5200     Result += "\tstruct objc_selector *_cmd;\n";
   5201     Result += "\tchar *method_types;\n";
   5202     Result += "};\n";
   5203 
   5204     objc_protocol_methods = true;
   5205   }
   5206   // Do not synthesize the protocol more than once.
   5207   if (ObjCSynthesizedProtocols.count(PDecl->getCanonicalDecl()))
   5208     return;
   5209 
   5210   if (ObjCProtocolDecl *Def = PDecl->getDefinition())
   5211     PDecl = Def;
   5212 
   5213   if (PDecl->instmeth_begin() != PDecl->instmeth_end()) {
   5214     unsigned NumMethods = std::distance(PDecl->instmeth_begin(),
   5215                                         PDecl->instmeth_end());
   5216     /* struct _objc_protocol_method_list {
   5217      int protocol_method_count;
   5218      struct protocol_methods protocols[];
   5219      }
   5220      */
   5221     Result += "\nstatic struct {\n";
   5222     Result += "\tint protocol_method_count;\n";
   5223     Result += "\tstruct _protocol_methods protocol_methods[";
   5224     Result += utostr(NumMethods);
   5225     Result += "];\n} _OBJC_PROTOCOL_INSTANCE_METHODS_";
   5226     Result += PDecl->getNameAsString();
   5227     Result += " __attribute__ ((used, section (\"__OBJC, __cat_inst_meth\")))= "
   5228     "{\n\t" + utostr(NumMethods) + "\n";
   5229 
   5230     // Output instance methods declared in this protocol.
   5231     for (ObjCProtocolDecl::instmeth_iterator
   5232          I = PDecl->instmeth_begin(), E = PDecl->instmeth_end();
   5233          I != E; ++I) {
   5234       if (I == PDecl->instmeth_begin())
   5235         Result += "\t  ,{{(struct objc_selector *)\"";
   5236       else
   5237         Result += "\t  ,{(struct objc_selector *)\"";
   5238       Result += (*I)->getSelector().getAsString();
   5239       std::string MethodTypeString;
   5240       Context->getObjCEncodingForMethodDecl((*I), MethodTypeString);
   5241       Result += "\", \"";
   5242       Result += MethodTypeString;
   5243       Result += "\"}\n";
   5244     }
   5245     Result += "\t }\n};\n";
   5246   }
   5247 
   5248   // Output class methods declared in this protocol.
   5249   unsigned NumMethods = std::distance(PDecl->classmeth_begin(),
   5250                                       PDecl->classmeth_end());
   5251   if (NumMethods > 0) {
   5252     /* struct _objc_protocol_method_list {
   5253      int protocol_method_count;
   5254      struct protocol_methods protocols[];
   5255      }
   5256      */
   5257     Result += "\nstatic struct {\n";
   5258     Result += "\tint protocol_method_count;\n";
   5259     Result += "\tstruct _protocol_methods protocol_methods[";
   5260     Result += utostr(NumMethods);
   5261     Result += "];\n} _OBJC_PROTOCOL_CLASS_METHODS_";
   5262     Result += PDecl->getNameAsString();
   5263     Result += " __attribute__ ((used, section (\"__OBJC, __cat_cls_meth\")))= "
   5264     "{\n\t";
   5265     Result += utostr(NumMethods);
   5266     Result += "\n";
   5267 
   5268     // Output instance methods declared in this protocol.
   5269     for (ObjCProtocolDecl::classmeth_iterator
   5270          I = PDecl->classmeth_begin(), E = PDecl->classmeth_end();
   5271          I != E; ++I) {
   5272       if (I == PDecl->classmeth_begin())
   5273         Result += "\t  ,{{(struct objc_selector *)\"";
   5274       else
   5275         Result += "\t  ,{(struct objc_selector *)\"";
   5276       Result += (*I)->getSelector().getAsString();
   5277       std::string MethodTypeString;
   5278       Context->getObjCEncodingForMethodDecl((*I), MethodTypeString);
   5279       Result += "\", \"";
   5280       Result += MethodTypeString;
   5281       Result += "\"}\n";
   5282     }
   5283     Result += "\t }\n};\n";
   5284   }
   5285 
   5286   // Output:
   5287   /* struct _objc_protocol {
   5288    // Objective-C 1.0 extensions
   5289    struct _objc_protocol_extension *isa;
   5290    char *protocol_name;
   5291    struct _objc_protocol **protocol_list;
   5292    struct _objc_protocol_method_list *instance_methods;
   5293    struct _objc_protocol_method_list *class_methods;
   5294    };
   5295    */
   5296   static bool objc_protocol = false;
   5297   if (!objc_protocol) {
   5298     Result += "\nstruct _objc_protocol {\n";
   5299     Result += "\tstruct _objc_protocol_extension *isa;\n";
   5300     Result += "\tchar *protocol_name;\n";
   5301     Result += "\tstruct _objc_protocol **protocol_list;\n";
   5302     Result += "\tstruct _objc_protocol_method_list *instance_methods;\n";
   5303     Result += "\tstruct _objc_protocol_method_list *class_methods;\n";
   5304     Result += "};\n";
   5305 
   5306     objc_protocol = true;
   5307   }
   5308 
   5309   Result += "\nstatic struct _objc_protocol _OBJC_PROTOCOL_";
   5310   Result += PDecl->getNameAsString();
   5311   Result += " __attribute__ ((used, section (\"__OBJC, __protocol\")))= "
   5312   "{\n\t0, \"";
   5313   Result += PDecl->getNameAsString();
   5314   Result += "\", 0, ";
   5315   if (PDecl->instmeth_begin() != PDecl->instmeth_end()) {
   5316     Result += "(struct _objc_protocol_method_list *)&_OBJC_PROTOCOL_INSTANCE_METHODS_";
   5317     Result += PDecl->getNameAsString();
   5318     Result += ", ";
   5319   }
   5320   else
   5321     Result += "0, ";
   5322   if (PDecl->classmeth_begin() != PDecl->classmeth_end()) {
   5323     Result += "(struct _objc_protocol_method_list *)&_OBJC_PROTOCOL_CLASS_METHODS_";
   5324     Result += PDecl->getNameAsString();
   5325     Result += "\n";
   5326   }
   5327   else
   5328     Result += "0\n";
   5329   Result += "};\n";
   5330 
   5331   // Mark this protocol as having been generated.
   5332   if (!ObjCSynthesizedProtocols.insert(PDecl->getCanonicalDecl()))
   5333     llvm_unreachable("protocol already synthesized");
   5334 
   5335 }
   5336 
   5337 void RewriteObjCFragileABI::RewriteObjCProtocolListMetaData(
   5338                                 const ObjCList<ObjCProtocolDecl> &Protocols,
   5339                                 StringRef prefix, StringRef ClassName,
   5340                                 std::string &Result) {
   5341   if (Protocols.empty()) return;
   5342 
   5343   for (unsigned i = 0; i != Protocols.size(); i++)
   5344     RewriteObjCProtocolMetaData(Protocols[i], prefix, ClassName, Result);
   5345 
   5346   // Output the top lovel protocol meta-data for the class.
   5347   /* struct _objc_protocol_list {
   5348    struct _objc_protocol_list *next;
   5349    int    protocol_count;
   5350    struct _objc_protocol *class_protocols[];
   5351    }
   5352    */
   5353   Result += "\nstatic struct {\n";
   5354   Result += "\tstruct _objc_protocol_list *next;\n";
   5355   Result += "\tint    protocol_count;\n";
   5356   Result += "\tstruct _objc_protocol *class_protocols[";
   5357   Result += utostr(Protocols.size());
   5358   Result += "];\n} _OBJC_";
   5359   Result += prefix;
   5360   Result += "_PROTOCOLS_";
   5361   Result += ClassName;
   5362   Result += " __attribute__ ((used, section (\"__OBJC, __cat_cls_meth\")))= "
   5363   "{\n\t0, ";
   5364   Result += utostr(Protocols.size());
   5365   Result += "\n";
   5366 
   5367   Result += "\t,{&_OBJC_PROTOCOL_";
   5368   Result += Protocols[0]->getNameAsString();
   5369   Result += " \n";
   5370 
   5371   for (unsigned i = 1; i != Protocols.size(); i++) {
   5372     Result += "\t ,&_OBJC_PROTOCOL_";
   5373     Result += Protocols[i]->getNameAsString();
   5374     Result += "\n";
   5375   }
   5376   Result += "\t }\n};\n";
   5377 }
   5378 
   5379 void RewriteObjCFragileABI::RewriteObjCClassMetaData(ObjCImplementationDecl *IDecl,
   5380                                            std::string &Result) {
   5381   ObjCInterfaceDecl *CDecl = IDecl->getClassInterface();
   5382 
   5383   // Explicitly declared @interface's are already synthesized.
   5384   if (CDecl->isImplicitInterfaceDecl()) {
   5385     // FIXME: Implementation of a class with no @interface (legacy) does not
   5386     // produce correct synthesis as yet.
   5387     RewriteObjCInternalStruct(CDecl, Result);
   5388   }
   5389 
   5390   // Build _objc_ivar_list metadata for classes ivars if needed
   5391   unsigned NumIvars = !IDecl->ivar_empty()
   5392   ? IDecl->ivar_size()
   5393   : (CDecl ? CDecl->ivar_size() : 0);
   5394   if (NumIvars > 0) {
   5395     static bool objc_ivar = false;
   5396     if (!objc_ivar) {
   5397       /* struct _objc_ivar {
   5398        char *ivar_name;
   5399        char *ivar_type;
   5400        int ivar_offset;
   5401        };
   5402        */
   5403       Result += "\nstruct _objc_ivar {\n";
   5404       Result += "\tchar *ivar_name;\n";
   5405       Result += "\tchar *ivar_type;\n";
   5406       Result += "\tint ivar_offset;\n";
   5407       Result += "};\n";
   5408 
   5409       objc_ivar = true;
   5410     }
   5411 
   5412     /* struct {
   5413      int ivar_count;
   5414      struct _objc_ivar ivar_list[nIvars];
   5415      };
   5416      */
   5417     Result += "\nstatic struct {\n";
   5418     Result += "\tint ivar_count;\n";
   5419     Result += "\tstruct _objc_ivar ivar_list[";
   5420     Result += utostr(NumIvars);
   5421     Result += "];\n} _OBJC_INSTANCE_VARIABLES_";
   5422     Result += IDecl->getNameAsString();
   5423     Result += " __attribute__ ((used, section (\"__OBJC, __instance_vars\")))= "
   5424     "{\n\t";
   5425     Result += utostr(NumIvars);
   5426     Result += "\n";
   5427 
   5428     ObjCInterfaceDecl::ivar_iterator IVI, IVE;
   5429     SmallVector<ObjCIvarDecl *, 8> IVars;
   5430     if (!IDecl->ivar_empty()) {
   5431       for (ObjCInterfaceDecl::ivar_iterator
   5432            IV = IDecl->ivar_begin(), IVEnd = IDecl->ivar_end();
   5433            IV != IVEnd; ++IV)
   5434         IVars.push_back(*IV);
   5435       IVI = IDecl->ivar_begin();
   5436       IVE = IDecl->ivar_end();
   5437     } else {
   5438       IVI = CDecl->ivar_begin();
   5439       IVE = CDecl->ivar_end();
   5440     }
   5441     Result += "\t,{{\"";
   5442     Result += IVI->getNameAsString();
   5443     Result += "\", \"";
   5444     std::string TmpString, StrEncoding;
   5445     Context->getObjCEncodingForType(IVI->getType(), TmpString, *IVI);
   5446     QuoteDoublequotes(TmpString, StrEncoding);
   5447     Result += StrEncoding;
   5448     Result += "\", ";
   5449     RewriteIvarOffsetComputation(*IVI, Result);
   5450     Result += "}\n";
   5451     for (++IVI; IVI != IVE; ++IVI) {
   5452       Result += "\t  ,{\"";
   5453       Result += IVI->getNameAsString();
   5454       Result += "\", \"";
   5455       std::string TmpString, StrEncoding;
   5456       Context->getObjCEncodingForType(IVI->getType(), TmpString, *IVI);
   5457       QuoteDoublequotes(TmpString, StrEncoding);
   5458       Result += StrEncoding;
   5459       Result += "\", ";
   5460       RewriteIvarOffsetComputation(*IVI, Result);
   5461       Result += "}\n";
   5462     }
   5463 
   5464     Result += "\t }\n};\n";
   5465   }
   5466 
   5467   // Build _objc_method_list for class's instance methods if needed
   5468   SmallVector<ObjCMethodDecl *, 32>
   5469   InstanceMethods(IDecl->instmeth_begin(), IDecl->instmeth_end());
   5470 
   5471   // If any of our property implementations have associated getters or
   5472   // setters, produce metadata for them as well.
   5473   for (ObjCImplDecl::propimpl_iterator Prop = IDecl->propimpl_begin(),
   5474        PropEnd = IDecl->propimpl_end();
   5475        Prop != PropEnd; ++Prop) {
   5476     if (Prop->getPropertyImplementation() == ObjCPropertyImplDecl::Dynamic)
   5477       continue;
   5478     if (!Prop->getPropertyIvarDecl())
   5479       continue;
   5480     ObjCPropertyDecl *PD = Prop->getPropertyDecl();
   5481     if (!PD)
   5482       continue;
   5483     if (ObjCMethodDecl *Getter = PD->getGetterMethodDecl())
   5484       if (!Getter->isDefined())
   5485         InstanceMethods.push_back(Getter);
   5486     if (PD->isReadOnly())
   5487       continue;
   5488     if (ObjCMethodDecl *Setter = PD->getSetterMethodDecl())
   5489       if (!Setter->isDefined())
   5490         InstanceMethods.push_back(Setter);
   5491   }
   5492   RewriteObjCMethodsMetaData(InstanceMethods.begin(), InstanceMethods.end(),
   5493                              true, "", IDecl->getName(), Result);
   5494 
   5495   // Build _objc_method_list for class's class methods if needed
   5496   RewriteObjCMethodsMetaData(IDecl->classmeth_begin(), IDecl->classmeth_end(),
   5497                              false, "", IDecl->getName(), Result);
   5498 
   5499   // Protocols referenced in class declaration?
   5500   RewriteObjCProtocolListMetaData(CDecl->getReferencedProtocols(),
   5501                                   "CLASS", CDecl->getName(), Result);
   5502 
   5503   // Declaration of class/meta-class metadata
   5504   /* struct _objc_class {
   5505    struct _objc_class *isa; // or const char *root_class_name when metadata
   5506    const char *super_class_name;
   5507    char *name;
   5508    long version;
   5509    long info;
   5510    long instance_size;
   5511    struct _objc_ivar_list *ivars;
   5512    struct _objc_method_list *methods;
   5513    struct objc_cache *cache;
   5514    struct objc_protocol_list *protocols;
   5515    const char *ivar_layout;
   5516    struct _objc_class_ext  *ext;
   5517    };
   5518    */
   5519   static bool objc_class = false;
   5520   if (!objc_class) {
   5521     Result += "\nstruct _objc_class {\n";
   5522     Result += "\tstruct _objc_class *isa;\n";
   5523     Result += "\tconst char *super_class_name;\n";
   5524     Result += "\tchar *name;\n";
   5525     Result += "\tlong version;\n";
   5526     Result += "\tlong info;\n";
   5527     Result += "\tlong instance_size;\n";
   5528     Result += "\tstruct _objc_ivar_list *ivars;\n";
   5529     Result += "\tstruct _objc_method_list *methods;\n";
   5530     Result += "\tstruct objc_cache *cache;\n";
   5531     Result += "\tstruct _objc_protocol_list *protocols;\n";
   5532     Result += "\tconst char *ivar_layout;\n";
   5533     Result += "\tstruct _objc_class_ext  *ext;\n";
   5534     Result += "};\n";
   5535     objc_class = true;
   5536   }
   5537 
   5538   // Meta-class metadata generation.
   5539   ObjCInterfaceDecl *RootClass = 0;
   5540   ObjCInterfaceDecl *SuperClass = CDecl->getSuperClass();
   5541   while (SuperClass) {
   5542     RootClass = SuperClass;
   5543     SuperClass = SuperClass->getSuperClass();
   5544   }
   5545   SuperClass = CDecl->getSuperClass();
   5546 
   5547   Result += "\nstatic struct _objc_class _OBJC_METACLASS_";
   5548   Result += CDecl->getNameAsString();
   5549   Result += " __attribute__ ((used, section (\"__OBJC, __meta_class\")))= "
   5550   "{\n\t(struct _objc_class *)\"";
   5551   Result += (RootClass ? RootClass->getNameAsString() : CDecl->getNameAsString());
   5552   Result += "\"";
   5553 
   5554   if (SuperClass) {
   5555     Result += ", \"";
   5556     Result += SuperClass->getNameAsString();
   5557     Result += "\", \"";
   5558     Result += CDecl->getNameAsString();
   5559     Result += "\"";
   5560   }
   5561   else {
   5562     Result += ", 0, \"";
   5563     Result += CDecl->getNameAsString();
   5564     Result += "\"";
   5565   }
   5566   // Set 'ivars' field for root class to 0. ObjC1 runtime does not use it.
   5567   // 'info' field is initialized to CLS_META(2) for metaclass
   5568   Result += ", 0,2, sizeof(struct _objc_class), 0";
   5569   if (IDecl->classmeth_begin() != IDecl->classmeth_end()) {
   5570     Result += "\n\t, (struct _objc_method_list *)&_OBJC_CLASS_METHODS_";
   5571     Result += IDecl->getNameAsString();
   5572     Result += "\n";
   5573   }
   5574   else
   5575     Result += ", 0\n";
   5576   if (CDecl->protocol_begin() != CDecl->protocol_end()) {
   5577     Result += "\t,0, (struct _objc_protocol_list *)&_OBJC_CLASS_PROTOCOLS_";
   5578     Result += CDecl->getNameAsString();
   5579     Result += ",0,0\n";
   5580   }
   5581   else
   5582     Result += "\t,0,0,0,0\n";
   5583   Result += "};\n";
   5584 
   5585   // class metadata generation.
   5586   Result += "\nstatic struct _objc_class _OBJC_CLASS_";
   5587   Result += CDecl->getNameAsString();
   5588   Result += " __attribute__ ((used, section (\"__OBJC, __class\")))= "
   5589   "{\n\t&_OBJC_METACLASS_";
   5590   Result += CDecl->getNameAsString();
   5591   if (SuperClass) {
   5592     Result += ", \"";
   5593     Result += SuperClass->getNameAsString();
   5594     Result += "\", \"";
   5595     Result += CDecl->getNameAsString();
   5596     Result += "\"";
   5597   }
   5598   else {
   5599     Result += ", 0, \"";
   5600     Result += CDecl->getNameAsString();
   5601     Result += "\"";
   5602   }
   5603   // 'info' field is initialized to CLS_CLASS(1) for class
   5604   Result += ", 0,1";
   5605   if (!ObjCSynthesizedStructs.count(CDecl))
   5606     Result += ",0";
   5607   else {
   5608     // class has size. Must synthesize its size.
   5609     Result += ",sizeof(struct ";
   5610     Result += CDecl->getNameAsString();
   5611     if (LangOpts.MicrosoftExt)
   5612       Result += "_IMPL";
   5613     Result += ")";
   5614   }
   5615   if (NumIvars > 0) {
   5616     Result += ", (struct _objc_ivar_list *)&_OBJC_INSTANCE_VARIABLES_";
   5617     Result += CDecl->getNameAsString();
   5618     Result += "\n\t";
   5619   }
   5620   else
   5621     Result += ",0";
   5622   if (IDecl->instmeth_begin() != IDecl->instmeth_end()) {
   5623     Result += ", (struct _objc_method_list *)&_OBJC_INSTANCE_METHODS_";
   5624     Result += CDecl->getNameAsString();
   5625     Result += ", 0\n\t";
   5626   }
   5627   else
   5628     Result += ",0,0";
   5629   if (CDecl->protocol_begin() != CDecl->protocol_end()) {
   5630     Result += ", (struct _objc_protocol_list*)&_OBJC_CLASS_PROTOCOLS_";
   5631     Result += CDecl->getNameAsString();
   5632     Result += ", 0,0\n";
   5633   }
   5634   else
   5635     Result += ",0,0,0\n";
   5636   Result += "};\n";
   5637 }
   5638 
   5639 void RewriteObjCFragileABI::RewriteMetaDataIntoBuffer(std::string &Result) {
   5640   int ClsDefCount = ClassImplementation.size();
   5641   int CatDefCount = CategoryImplementation.size();
   5642 
   5643   // For each implemented class, write out all its meta data.
   5644   for (int i = 0; i < ClsDefCount; i++)
   5645     RewriteObjCClassMetaData(ClassImplementation[i], Result);
   5646 
   5647   // For each implemented category, write out all its meta data.
   5648   for (int i = 0; i < CatDefCount; i++)
   5649     RewriteObjCCategoryImplDecl(CategoryImplementation[i], Result);
   5650 
   5651   // Write objc_symtab metadata
   5652   /*
   5653    struct _objc_symtab
   5654    {
   5655    long sel_ref_cnt;
   5656    SEL *refs;
   5657    short cls_def_cnt;
   5658    short cat_def_cnt;
   5659    void *defs[cls_def_cnt + cat_def_cnt];
   5660    };
   5661    */
   5662 
   5663   Result += "\nstruct _objc_symtab {\n";
   5664   Result += "\tlong sel_ref_cnt;\n";
   5665   Result += "\tSEL *refs;\n";
   5666   Result += "\tshort cls_def_cnt;\n";
   5667   Result += "\tshort cat_def_cnt;\n";
   5668   Result += "\tvoid *defs[" + utostr(ClsDefCount + CatDefCount)+ "];\n";
   5669   Result += "};\n\n";
   5670 
   5671   Result += "static struct _objc_symtab "
   5672   "_OBJC_SYMBOLS __attribute__((used, section (\"__OBJC, __symbols\")))= {\n";
   5673   Result += "\t0, 0, " + utostr(ClsDefCount)
   5674   + ", " + utostr(CatDefCount) + "\n";
   5675   for (int i = 0; i < ClsDefCount; i++) {
   5676     Result += "\t,&_OBJC_CLASS_";
   5677     Result += ClassImplementation[i]->getNameAsString();
   5678     Result += "\n";
   5679   }
   5680 
   5681   for (int i = 0; i < CatDefCount; i++) {
   5682     Result += "\t,&_OBJC_CATEGORY_";
   5683     Result += CategoryImplementation[i]->getClassInterface()->getNameAsString();
   5684     Result += "_";
   5685     Result += CategoryImplementation[i]->getNameAsString();
   5686     Result += "\n";
   5687   }
   5688 
   5689   Result += "};\n\n";
   5690 
   5691   // Write objc_module metadata
   5692 
   5693   /*
   5694    struct _objc_module {
   5695    long version;
   5696    long size;
   5697    const char *name;
   5698    struct _objc_symtab *symtab;
   5699    }
   5700    */
   5701 
   5702   Result += "\nstruct _objc_module {\n";
   5703   Result += "\tlong version;\n";
   5704   Result += "\tlong size;\n";
   5705   Result += "\tconst char *name;\n";
   5706   Result += "\tstruct _objc_symtab *symtab;\n";
   5707   Result += "};\n\n";
   5708   Result += "static struct _objc_module "
   5709   "_OBJC_MODULES __attribute__ ((used, section (\"__OBJC, __module_info\")))= {\n";
   5710   Result += "\t" + utostr(OBJC_ABI_VERSION) +
   5711   ", sizeof(struct _objc_module), \"\", &_OBJC_SYMBOLS\n";
   5712   Result += "};\n\n";
   5713 
   5714   if (LangOpts.MicrosoftExt) {
   5715     if (ProtocolExprDecls.size()) {
   5716       Result += "#pragma section(\".objc_protocol$B\",long,read,write)\n";
   5717       Result += "#pragma data_seg(push, \".objc_protocol$B\")\n";
   5718       for (llvm::SmallPtrSet<ObjCProtocolDecl *,8>::iterator I = ProtocolExprDecls.begin(),
   5719            E = ProtocolExprDecls.end(); I != E; ++I) {
   5720         Result += "static struct _objc_protocol *_POINTER_OBJC_PROTOCOL_";
   5721         Result += (*I)->getNameAsString();
   5722         Result += " = &_OBJC_PROTOCOL_";
   5723         Result += (*I)->getNameAsString();
   5724         Result += ";\n";
   5725       }
   5726       Result += "#pragma data_seg(pop)\n\n";
   5727     }
   5728     Result += "#pragma section(\".objc_module_info$B\",long,read,write)\n";
   5729     Result += "#pragma data_seg(push, \".objc_module_info$B\")\n";
   5730     Result += "static struct _objc_module *_POINTER_OBJC_MODULES = ";
   5731     Result += "&_OBJC_MODULES;\n";
   5732     Result += "#pragma data_seg(pop)\n\n";
   5733   }
   5734 }
   5735 
   5736 /// RewriteObjCCategoryImplDecl - Rewrite metadata for each category
   5737 /// implementation.
   5738 void RewriteObjCFragileABI::RewriteObjCCategoryImplDecl(ObjCCategoryImplDecl *IDecl,
   5739                                               std::string &Result) {
   5740   ObjCInterfaceDecl *ClassDecl = IDecl->getClassInterface();
   5741   // Find category declaration for this implementation.
   5742   ObjCCategoryDecl *CDecl
   5743     = ClassDecl->FindCategoryDeclaration(IDecl->getIdentifier());
   5744 
   5745   std::string FullCategoryName = ClassDecl->getNameAsString();
   5746   FullCategoryName += '_';
   5747   FullCategoryName += IDecl->getNameAsString();
   5748 
   5749   // Build _objc_method_list for class's instance methods if needed
   5750   SmallVector<ObjCMethodDecl *, 32>
   5751   InstanceMethods(IDecl->instmeth_begin(), IDecl->instmeth_end());
   5752 
   5753   // If any of our property implementations have associated getters or
   5754   // setters, produce metadata for them as well.
   5755   for (ObjCImplDecl::propimpl_iterator Prop = IDecl->propimpl_begin(),
   5756        PropEnd = IDecl->propimpl_end();
   5757        Prop != PropEnd; ++Prop) {
   5758     if (Prop->getPropertyImplementation() == ObjCPropertyImplDecl::Dynamic)
   5759       continue;
   5760     if (!Prop->getPropertyIvarDecl())
   5761       continue;
   5762     ObjCPropertyDecl *PD = Prop->getPropertyDecl();
   5763     if (!PD)
   5764       continue;
   5765     if (ObjCMethodDecl *Getter = PD->getGetterMethodDecl())
   5766       InstanceMethods.push_back(Getter);
   5767     if (PD->isReadOnly())
   5768       continue;
   5769     if (ObjCMethodDecl *Setter = PD->getSetterMethodDecl())
   5770       InstanceMethods.push_back(Setter);
   5771   }
   5772   RewriteObjCMethodsMetaData(InstanceMethods.begin(), InstanceMethods.end(),
   5773                              true, "CATEGORY_", FullCategoryName.c_str(),
   5774                              Result);
   5775 
   5776   // Build _objc_method_list for class's class methods if needed
   5777   RewriteObjCMethodsMetaData(IDecl->classmeth_begin(), IDecl->classmeth_end(),
   5778                              false, "CATEGORY_", FullCategoryName.c_str(),
   5779                              Result);
   5780 
   5781   // Protocols referenced in class declaration?
   5782   // Null CDecl is case of a category implementation with no category interface
   5783   if (CDecl)
   5784     RewriteObjCProtocolListMetaData(CDecl->getReferencedProtocols(), "CATEGORY",
   5785                                     FullCategoryName, Result);
   5786   /* struct _objc_category {
   5787    char *category_name;
   5788    char *class_name;
   5789    struct _objc_method_list *instance_methods;
   5790    struct _objc_method_list *class_methods;
   5791    struct _objc_protocol_list *protocols;
   5792    // Objective-C 1.0 extensions
   5793    uint32_t size;     // sizeof (struct _objc_category)
   5794    struct _objc_property_list *instance_properties;  // category's own
   5795    // @property decl.
   5796    };
   5797    */
   5798 
   5799   static bool objc_category = false;
   5800   if (!objc_category) {
   5801     Result += "\nstruct _objc_category {\n";
   5802     Result += "\tchar *category_name;\n";
   5803     Result += "\tchar *class_name;\n";
   5804     Result += "\tstruct _objc_method_list *instance_methods;\n";
   5805     Result += "\tstruct _objc_method_list *class_methods;\n";
   5806     Result += "\tstruct _objc_protocol_list *protocols;\n";
   5807     Result += "\tunsigned int size;\n";
   5808     Result += "\tstruct _objc_property_list *instance_properties;\n";
   5809     Result += "};\n";
   5810     objc_category = true;
   5811   }
   5812   Result += "\nstatic struct _objc_category _OBJC_CATEGORY_";
   5813   Result += FullCategoryName;
   5814   Result += " __attribute__ ((used, section (\"__OBJC, __category\")))= {\n\t\"";
   5815   Result += IDecl->getNameAsString();
   5816   Result += "\"\n\t, \"";
   5817   Result += ClassDecl->getNameAsString();
   5818   Result += "\"\n";
   5819 
   5820   if (IDecl->instmeth_begin() != IDecl->instmeth_end()) {
   5821     Result += "\t, (struct _objc_method_list *)"
   5822     "&_OBJC_CATEGORY_INSTANCE_METHODS_";
   5823     Result += FullCategoryName;
   5824     Result += "\n";
   5825   }
   5826   else
   5827     Result += "\t, 0\n";
   5828   if (IDecl->classmeth_begin() != IDecl->classmeth_end()) {
   5829     Result += "\t, (struct _objc_method_list *)"
   5830     "&_OBJC_CATEGORY_CLASS_METHODS_";
   5831     Result += FullCategoryName;
   5832     Result += "\n";
   5833   }
   5834   else
   5835     Result += "\t, 0\n";
   5836 
   5837   if (CDecl && CDecl->protocol_begin() != CDecl->protocol_end()) {
   5838     Result += "\t, (struct _objc_protocol_list *)&_OBJC_CATEGORY_PROTOCOLS_";
   5839     Result += FullCategoryName;
   5840     Result += "\n";
   5841   }
   5842   else
   5843     Result += "\t, 0\n";
   5844   Result += "\t, sizeof(struct _objc_category), 0\n};\n";
   5845 }
   5846 
   5847 // RewriteObjCMethodsMetaData - Rewrite methods metadata for instance or
   5848 /// class methods.
   5849 template<typename MethodIterator>
   5850 void RewriteObjCFragileABI::RewriteObjCMethodsMetaData(MethodIterator MethodBegin,
   5851                                              MethodIterator MethodEnd,
   5852                                              bool IsInstanceMethod,
   5853                                              StringRef prefix,
   5854                                              StringRef ClassName,
   5855                                              std::string &Result) {
   5856   if (MethodBegin == MethodEnd) return;
   5857 
   5858   if (!objc_impl_method) {
   5859     /* struct _objc_method {
   5860      SEL _cmd;
   5861      char *method_types;
   5862      void *_imp;
   5863      }
   5864      */
   5865     Result += "\nstruct _objc_method {\n";
   5866     Result += "\tSEL _cmd;\n";
   5867     Result += "\tchar *method_types;\n";
   5868     Result += "\tvoid *_imp;\n";
   5869     Result += "};\n";
   5870 
   5871     objc_impl_method = true;
   5872   }
   5873 
   5874   // Build _objc_method_list for class's methods if needed
   5875 
   5876   /* struct  {
   5877    struct _objc_method_list *next_method;
   5878    int method_count;
   5879    struct _objc_method method_list[];
   5880    }
   5881    */
   5882   unsigned NumMethods = std::distance(MethodBegin, MethodEnd);
   5883   Result += "\nstatic struct {\n";
   5884   Result += "\tstruct _objc_method_list *next_method;\n";
   5885   Result += "\tint method_count;\n";
   5886   Result += "\tstruct _objc_method method_list[";
   5887   Result += utostr(NumMethods);
   5888   Result += "];\n} _OBJC_";
   5889   Result += prefix;
   5890   Result += IsInstanceMethod ? "INSTANCE" : "CLASS";
   5891   Result += "_METHODS_";
   5892   Result += ClassName;
   5893   Result += " __attribute__ ((used, section (\"__OBJC, __";
   5894   Result += IsInstanceMethod ? "inst" : "cls";
   5895   Result += "_meth\")))= ";
   5896   Result += "{\n\t0, " + utostr(NumMethods) + "\n";
   5897 
   5898   Result += "\t,{{(SEL)\"";
   5899   Result += (*MethodBegin)->getSelector().getAsString().c_str();
   5900   std::string MethodTypeString;
   5901   Context->getObjCEncodingForMethodDecl(*MethodBegin, MethodTypeString);
   5902   Result += "\", \"";
   5903   Result += MethodTypeString;
   5904   Result += "\", (void *)";
   5905   Result += MethodInternalNames[*MethodBegin];
   5906   Result += "}\n";
   5907   for (++MethodBegin; MethodBegin != MethodEnd; ++MethodBegin) {
   5908     Result += "\t  ,{(SEL)\"";
   5909     Result += (*MethodBegin)->getSelector().getAsString().c_str();
   5910     std::string MethodTypeString;
   5911     Context->getObjCEncodingForMethodDecl(*MethodBegin, MethodTypeString);
   5912     Result += "\", \"";
   5913     Result += MethodTypeString;
   5914     Result += "\", (void *)";
   5915     Result += MethodInternalNames[*MethodBegin];
   5916     Result += "}\n";
   5917   }
   5918   Result += "\t }\n};\n";
   5919 }
   5920 
   5921 Stmt *RewriteObjCFragileABI::RewriteObjCIvarRefExpr(ObjCIvarRefExpr *IV) {
   5922   SourceRange OldRange = IV->getSourceRange();
   5923   Expr *BaseExpr = IV->getBase();
   5924 
   5925   // Rewrite the base, but without actually doing replaces.
   5926   {
   5927     DisableReplaceStmtScope S(*this);
   5928     BaseExpr = cast<Expr>(RewriteFunctionBodyOrGlobalInitializer(BaseExpr));
   5929     IV->setBase(BaseExpr);
   5930   }
   5931 
   5932   ObjCIvarDecl *D = IV->getDecl();
   5933 
   5934   Expr *Replacement = IV;
   5935   if (CurMethodDef) {
   5936     if (BaseExpr->getType()->isObjCObjectPointerType()) {
   5937       const ObjCInterfaceType *iFaceDecl =
   5938       dyn_cast<ObjCInterfaceType>(BaseExpr->getType()->getPointeeType());
   5939       assert(iFaceDecl && "RewriteObjCIvarRefExpr - iFaceDecl is null");
   5940       // lookup which class implements the instance variable.
   5941       ObjCInterfaceDecl *clsDeclared = 0;
   5942       iFaceDecl->getDecl()->lookupInstanceVariable(D->getIdentifier(),
   5943                                                    clsDeclared);
   5944       assert(clsDeclared && "RewriteObjCIvarRefExpr(): Can't find class");
   5945 
   5946       // Synthesize an explicit cast to gain access to the ivar.
   5947       std::string RecName = clsDeclared->getIdentifier()->getName();
   5948       RecName += "_IMPL";
   5949       IdentifierInfo *II = &Context->Idents.get(RecName);
   5950       RecordDecl *RD = RecordDecl::Create(*Context, TTK_Struct, TUDecl,
   5951                                           SourceLocation(), SourceLocation(),
   5952                                           II);
   5953       assert(RD && "RewriteObjCIvarRefExpr(): Can't find RecordDecl");
   5954       QualType castT = Context->getPointerType(Context->getTagDeclType(RD));
   5955       CastExpr *castExpr = NoTypeInfoCStyleCastExpr(Context, castT,
   5956                                                     CK_BitCast,
   5957                                                     IV->getBase());
   5958       // Don't forget the parens to enforce the proper binding.
   5959       ParenExpr *PE = new (Context) ParenExpr(OldRange.getBegin(),
   5960                                               OldRange.getEnd(),
   5961                                               castExpr);
   5962       if (IV->isFreeIvar() &&
   5963           declaresSameEntity(CurMethodDef->getClassInterface(), iFaceDecl->getDecl())) {
   5964         MemberExpr *ME = new (Context) MemberExpr(PE, true, D,
   5965                                                   IV->getLocation(),
   5966                                                   D->getType(),
   5967                                                   VK_LValue, OK_Ordinary);
   5968         Replacement = ME;
   5969       } else {
   5970         IV->setBase(PE);
   5971       }
   5972     }
   5973   } else { // we are outside a method.
   5974     assert(!IV->isFreeIvar() && "Cannot have a free standing ivar outside a method");
   5975 
   5976     // Explicit ivar refs need to have a cast inserted.
   5977     // FIXME: consider sharing some of this code with the code above.
   5978     if (BaseExpr->getType()->isObjCObjectPointerType()) {
   5979       const ObjCInterfaceType *iFaceDecl =
   5980       dyn_cast<ObjCInterfaceType>(BaseExpr->getType()->getPointeeType());
   5981       // lookup which class implements the instance variable.
   5982       ObjCInterfaceDecl *clsDeclared = 0;
   5983       iFaceDecl->getDecl()->lookupInstanceVariable(D->getIdentifier(),
   5984                                                    clsDeclared);
   5985       assert(clsDeclared && "RewriteObjCIvarRefExpr(): Can't find class");
   5986 
   5987       // Synthesize an explicit cast to gain access to the ivar.
   5988       std::string RecName = clsDeclared->getIdentifier()->getName();
   5989       RecName += "_IMPL";
   5990       IdentifierInfo *II = &Context->Idents.get(RecName);
   5991       RecordDecl *RD = RecordDecl::Create(*Context, TTK_Struct, TUDecl,
   5992                                           SourceLocation(), SourceLocation(),
   5993                                           II);
   5994       assert(RD && "RewriteObjCIvarRefExpr(): Can't find RecordDecl");
   5995       QualType castT = Context->getPointerType(Context->getTagDeclType(RD));
   5996       CastExpr *castExpr = NoTypeInfoCStyleCastExpr(Context, castT,
   5997                                                     CK_BitCast,
   5998                                                     IV->getBase());
   5999       // Don't forget the parens to enforce the proper binding.
   6000       ParenExpr *PE = new (Context) ParenExpr(IV->getBase()->getLocStart(),
   6001                                               IV->getBase()->getLocEnd(), castExpr);
   6002       // Cannot delete IV->getBase(), since PE points to it.
   6003       // Replace the old base with the cast. This is important when doing
   6004       // embedded rewrites. For example, [newInv->_container addObject:0].
   6005       IV->setBase(PE);
   6006     }
   6007   }
   6008 
   6009   ReplaceStmtWithRange(IV, Replacement, OldRange);
   6010   return Replacement;
   6011 }
   6012