xref: /freebsd/contrib/llvm-project/clang/lib/Frontend/Rewrite/RewriteObjC.cpp (revision 77a1348b3c1cfe8547be49a121b56299a1e18b69)
1 //===--- RewriteObjC.cpp - Playground for the code rewriter ---------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // Hacks and fun related to the code rewriter.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "clang/Rewrite/Frontend/ASTConsumers.h"
14 #include "clang/AST/AST.h"
15 #include "clang/AST/ASTConsumer.h"
16 #include "clang/AST/Attr.h"
17 #include "clang/AST/ParentMap.h"
18 #include "clang/Basic/CharInfo.h"
19 #include "clang/Basic/Diagnostic.h"
20 #include "clang/Basic/IdentifierTable.h"
21 #include "clang/Basic/SourceManager.h"
22 #include "clang/Config/config.h"
23 #include "clang/Lex/Lexer.h"
24 #include "clang/Rewrite/Core/Rewriter.h"
25 #include "llvm/ADT/DenseSet.h"
26 #include "llvm/ADT/SmallPtrSet.h"
27 #include "llvm/ADT/StringExtras.h"
28 #include "llvm/Support/MemoryBuffer.h"
29 #include "llvm/Support/raw_ostream.h"
30 #include <memory>
31 
32 #if CLANG_ENABLE_OBJC_REWRITER
33 
34 using namespace clang;
35 using llvm::utostr;
36 
37 namespace {
38   class RewriteObjC : public ASTConsumer {
39   protected:
40     enum {
41       BLOCK_FIELD_IS_OBJECT   =  3,  /* id, NSObject, __attribute__((NSObject)),
42                                         block, ... */
43       BLOCK_FIELD_IS_BLOCK    =  7,  /* a block variable */
44       BLOCK_FIELD_IS_BYREF    =  8,  /* the on stack structure holding the
45                                         __block variable */
46       BLOCK_FIELD_IS_WEAK     = 16,  /* declared __weak, only used in byref copy
47                                         helpers */
48       BLOCK_BYREF_CALLER      = 128, /* called from __block (byref) copy/dispose
49                                         support routines */
50       BLOCK_BYREF_CURRENT_MAX = 256
51     };
52 
53     enum {
54       BLOCK_NEEDS_FREE =        (1 << 24),
55       BLOCK_HAS_COPY_DISPOSE =  (1 << 25),
56       BLOCK_HAS_CXX_OBJ =       (1 << 26),
57       BLOCK_IS_GC =             (1 << 27),
58       BLOCK_IS_GLOBAL =         (1 << 28),
59       BLOCK_HAS_DESCRIPTOR =    (1 << 29)
60     };
61     static const int OBJC_ABI_VERSION = 7;
62 
63     Rewriter Rewrite;
64     DiagnosticsEngine &Diags;
65     const LangOptions &LangOpts;
66     ASTContext *Context;
67     SourceManager *SM;
68     TranslationUnitDecl *TUDecl;
69     FileID MainFileID;
70     const char *MainFileStart, *MainFileEnd;
71     Stmt *CurrentBody;
72     ParentMap *PropParentMap; // created lazily.
73     std::string InFileName;
74     std::unique_ptr<raw_ostream> OutFile;
75     std::string Preamble;
76 
77     TypeDecl *ProtocolTypeDecl;
78     VarDecl *GlobalVarDecl;
79     unsigned RewriteFailedDiag;
80     // ObjC string constant support.
81     unsigned NumObjCStringLiterals;
82     VarDecl *ConstantStringClassReference;
83     RecordDecl *NSStringRecord;
84 
85     // ObjC foreach break/continue generation support.
86     int BcLabelCount;
87 
88     unsigned TryFinallyContainsReturnDiag;
89     // Needed for super.
90     ObjCMethodDecl *CurMethodDef;
91     RecordDecl *SuperStructDecl;
92     RecordDecl *ConstantStringDecl;
93 
94     FunctionDecl *MsgSendFunctionDecl;
95     FunctionDecl *MsgSendSuperFunctionDecl;
96     FunctionDecl *MsgSendStretFunctionDecl;
97     FunctionDecl *MsgSendSuperStretFunctionDecl;
98     FunctionDecl *MsgSendFpretFunctionDecl;
99     FunctionDecl *GetClassFunctionDecl;
100     FunctionDecl *GetMetaClassFunctionDecl;
101     FunctionDecl *GetSuperClassFunctionDecl;
102     FunctionDecl *SelGetUidFunctionDecl;
103     FunctionDecl *CFStringFunctionDecl;
104     FunctionDecl *SuperConstructorFunctionDecl;
105     FunctionDecl *CurFunctionDef;
106     FunctionDecl *CurFunctionDeclToDeclareForBlock;
107 
108     /* Misc. containers needed for meta-data rewrite. */
109     SmallVector<ObjCImplementationDecl *, 8> ClassImplementation;
110     SmallVector<ObjCCategoryImplDecl *, 8> CategoryImplementation;
111     llvm::SmallPtrSet<ObjCInterfaceDecl*, 8> ObjCSynthesizedStructs;
112     llvm::SmallPtrSet<ObjCProtocolDecl*, 8> ObjCSynthesizedProtocols;
113     llvm::SmallPtrSet<ObjCInterfaceDecl*, 8> ObjCForwardDecls;
114     llvm::DenseMap<ObjCMethodDecl*, std::string> MethodInternalNames;
115     SmallVector<Stmt *, 32> Stmts;
116     SmallVector<int, 8> ObjCBcLabelNo;
117     // Remember all the @protocol(<expr>) expressions.
118     llvm::SmallPtrSet<ObjCProtocolDecl *, 32> ProtocolExprDecls;
119 
120     llvm::DenseSet<uint64_t> CopyDestroyCache;
121 
122     // Block expressions.
123     SmallVector<BlockExpr *, 32> Blocks;
124     SmallVector<int, 32> InnerDeclRefsCount;
125     SmallVector<DeclRefExpr *, 32> InnerDeclRefs;
126 
127     SmallVector<DeclRefExpr *, 32> BlockDeclRefs;
128 
129     // Block related declarations.
130     SmallVector<ValueDecl *, 8> BlockByCopyDecls;
131     llvm::SmallPtrSet<ValueDecl *, 8> BlockByCopyDeclsPtrSet;
132     SmallVector<ValueDecl *, 8> BlockByRefDecls;
133     llvm::SmallPtrSet<ValueDecl *, 8> BlockByRefDeclsPtrSet;
134     llvm::DenseMap<ValueDecl *, unsigned> BlockByRefDeclNo;
135     llvm::SmallPtrSet<ValueDecl *, 8> ImportedBlockDecls;
136     llvm::SmallPtrSet<VarDecl *, 8> ImportedLocalExternalDecls;
137 
138     llvm::DenseMap<BlockExpr *, std::string> RewrittenBlockExprs;
139 
140     // This maps an original source AST to it's rewritten form. This allows
141     // us to avoid rewriting the same node twice (which is very uncommon).
142     // This is needed to support some of the exotic property rewriting.
143     llvm::DenseMap<Stmt *, Stmt *> ReplacedNodes;
144 
145     // Needed for header files being rewritten
146     bool IsHeader;
147     bool SilenceRewriteMacroWarning;
148     bool objc_impl_method;
149 
150     bool DisableReplaceStmt;
151     class DisableReplaceStmtScope {
152       RewriteObjC &R;
153       bool SavedValue;
154 
155     public:
156       DisableReplaceStmtScope(RewriteObjC &R)
157         : R(R), SavedValue(R.DisableReplaceStmt) {
158         R.DisableReplaceStmt = true;
159       }
160 
161       ~DisableReplaceStmtScope() {
162         R.DisableReplaceStmt = SavedValue;
163       }
164     };
165 
166     void InitializeCommon(ASTContext &context);
167 
168   public:
169     // Top Level Driver code.
170     bool HandleTopLevelDecl(DeclGroupRef D) override {
171       for (DeclGroupRef::iterator I = D.begin(), E = D.end(); I != E; ++I) {
172         if (ObjCInterfaceDecl *Class = dyn_cast<ObjCInterfaceDecl>(*I)) {
173           if (!Class->isThisDeclarationADefinition()) {
174             RewriteForwardClassDecl(D);
175             break;
176           }
177         }
178 
179         if (ObjCProtocolDecl *Proto = dyn_cast<ObjCProtocolDecl>(*I)) {
180           if (!Proto->isThisDeclarationADefinition()) {
181             RewriteForwardProtocolDecl(D);
182             break;
183           }
184         }
185 
186         HandleTopLevelSingleDecl(*I);
187       }
188       return true;
189     }
190 
191     void HandleTopLevelSingleDecl(Decl *D);
192     void HandleDeclInMainFile(Decl *D);
193     RewriteObjC(std::string inFile, std::unique_ptr<raw_ostream> OS,
194                 DiagnosticsEngine &D, const LangOptions &LOpts,
195                 bool silenceMacroWarn);
196 
197     ~RewriteObjC() override {}
198 
199     void HandleTranslationUnit(ASTContext &C) override;
200 
201     void ReplaceStmt(Stmt *Old, Stmt *New) {
202       ReplaceStmtWithRange(Old, New, Old->getSourceRange());
203     }
204 
205     void ReplaceStmtWithRange(Stmt *Old, Stmt *New, SourceRange SrcRange) {
206       assert(Old != nullptr && New != nullptr && "Expected non-null Stmt's");
207 
208       Stmt *ReplacingStmt = ReplacedNodes[Old];
209       if (ReplacingStmt)
210         return; // We can't rewrite the same node twice.
211 
212       if (DisableReplaceStmt)
213         return;
214 
215       // Measure the old text.
216       int Size = Rewrite.getRangeSize(SrcRange);
217       if (Size == -1) {
218         Diags.Report(Context->getFullLoc(Old->getBeginLoc()), RewriteFailedDiag)
219             << Old->getSourceRange();
220         return;
221       }
222       // Get the new text.
223       std::string SStr;
224       llvm::raw_string_ostream S(SStr);
225       New->printPretty(S, nullptr, PrintingPolicy(LangOpts));
226       const std::string &Str = S.str();
227 
228       // If replacement succeeded or warning disabled return with no warning.
229       if (!Rewrite.ReplaceText(SrcRange.getBegin(), Size, Str)) {
230         ReplacedNodes[Old] = New;
231         return;
232       }
233       if (SilenceRewriteMacroWarning)
234         return;
235       Diags.Report(Context->getFullLoc(Old->getBeginLoc()), RewriteFailedDiag)
236           << Old->getSourceRange();
237     }
238 
239     void InsertText(SourceLocation Loc, StringRef Str,
240                     bool InsertAfter = true) {
241       // If insertion succeeded or warning disabled return with no warning.
242       if (!Rewrite.InsertText(Loc, Str, InsertAfter) ||
243           SilenceRewriteMacroWarning)
244         return;
245 
246       Diags.Report(Context->getFullLoc(Loc), RewriteFailedDiag);
247     }
248 
249     void ReplaceText(SourceLocation Start, unsigned OrigLength,
250                      StringRef Str) {
251       // If removal succeeded or warning disabled return with no warning.
252       if (!Rewrite.ReplaceText(Start, OrigLength, Str) ||
253           SilenceRewriteMacroWarning)
254         return;
255 
256       Diags.Report(Context->getFullLoc(Start), RewriteFailedDiag);
257     }
258 
259     // Syntactic Rewriting.
260     void RewriteRecordBody(RecordDecl *RD);
261     void RewriteInclude();
262     void RewriteForwardClassDecl(DeclGroupRef D);
263     void RewriteForwardClassDecl(const SmallVectorImpl<Decl *> &DG);
264     void RewriteForwardClassEpilogue(ObjCInterfaceDecl *ClassDecl,
265                                      const std::string &typedefString);
266     void RewriteImplementations();
267     void RewritePropertyImplDecl(ObjCPropertyImplDecl *PID,
268                                  ObjCImplementationDecl *IMD,
269                                  ObjCCategoryImplDecl *CID);
270     void RewriteInterfaceDecl(ObjCInterfaceDecl *Dcl);
271     void RewriteImplementationDecl(Decl *Dcl);
272     void RewriteObjCMethodDecl(const ObjCInterfaceDecl *IDecl,
273                                ObjCMethodDecl *MDecl, std::string &ResultStr);
274     void RewriteTypeIntoString(QualType T, std::string &ResultStr,
275                                const FunctionType *&FPRetType);
276     void RewriteByRefString(std::string &ResultStr, const std::string &Name,
277                             ValueDecl *VD, bool def=false);
278     void RewriteCategoryDecl(ObjCCategoryDecl *Dcl);
279     void RewriteProtocolDecl(ObjCProtocolDecl *Dcl);
280     void RewriteForwardProtocolDecl(DeclGroupRef D);
281     void RewriteForwardProtocolDecl(const SmallVectorImpl<Decl *> &DG);
282     void RewriteMethodDeclaration(ObjCMethodDecl *Method);
283     void RewriteProperty(ObjCPropertyDecl *prop);
284     void RewriteFunctionDecl(FunctionDecl *FD);
285     void RewriteBlockPointerType(std::string& Str, QualType Type);
286     void RewriteBlockPointerTypeVariable(std::string& Str, ValueDecl *VD);
287     void RewriteBlockLiteralFunctionDecl(FunctionDecl *FD);
288     void RewriteObjCQualifiedInterfaceTypes(Decl *Dcl);
289     void RewriteTypeOfDecl(VarDecl *VD);
290     void RewriteObjCQualifiedInterfaceTypes(Expr *E);
291 
292     // Expression Rewriting.
293     Stmt *RewriteFunctionBodyOrGlobalInitializer(Stmt *S);
294     Stmt *RewriteAtEncode(ObjCEncodeExpr *Exp);
295     Stmt *RewritePropertyOrImplicitGetter(PseudoObjectExpr *Pseudo);
296     Stmt *RewritePropertyOrImplicitSetter(PseudoObjectExpr *Pseudo);
297     Stmt *RewriteAtSelector(ObjCSelectorExpr *Exp);
298     Stmt *RewriteMessageExpr(ObjCMessageExpr *Exp);
299     Stmt *RewriteObjCStringLiteral(ObjCStringLiteral *Exp);
300     Stmt *RewriteObjCProtocolExpr(ObjCProtocolExpr *Exp);
301     void RewriteTryReturnStmts(Stmt *S);
302     void RewriteSyncReturnStmts(Stmt *S, std::string buf);
303     Stmt *RewriteObjCTryStmt(ObjCAtTryStmt *S);
304     Stmt *RewriteObjCSynchronizedStmt(ObjCAtSynchronizedStmt *S);
305     Stmt *RewriteObjCThrowStmt(ObjCAtThrowStmt *S);
306     Stmt *RewriteObjCForCollectionStmt(ObjCForCollectionStmt *S,
307                                        SourceLocation OrigEnd);
308     Stmt *RewriteBreakStmt(BreakStmt *S);
309     Stmt *RewriteContinueStmt(ContinueStmt *S);
310     void RewriteCastExpr(CStyleCastExpr *CE);
311 
312     // Block rewriting.
313     void RewriteBlocksInFunctionProtoType(QualType funcType, NamedDecl *D);
314 
315     // Block specific rewrite rules.
316     void RewriteBlockPointerDecl(NamedDecl *VD);
317     void RewriteByRefVar(VarDecl *VD);
318     Stmt *RewriteBlockDeclRefExpr(DeclRefExpr *VD);
319     Stmt *RewriteLocalVariableExternalStorage(DeclRefExpr *DRE);
320     void RewriteBlockPointerFunctionArgs(FunctionDecl *FD);
321 
322     void RewriteObjCInternalStruct(ObjCInterfaceDecl *CDecl,
323                                       std::string &Result);
324 
325     void Initialize(ASTContext &context) override = 0;
326 
327     // Metadata Rewriting.
328     virtual void RewriteMetaDataIntoBuffer(std::string &Result) = 0;
329     virtual void RewriteObjCProtocolListMetaData(const ObjCList<ObjCProtocolDecl> &Prots,
330                                                  StringRef prefix,
331                                                  StringRef ClassName,
332                                                  std::string &Result) = 0;
333     virtual void RewriteObjCCategoryImplDecl(ObjCCategoryImplDecl *CDecl,
334                                              std::string &Result) = 0;
335     virtual void RewriteObjCProtocolMetaData(ObjCProtocolDecl *Protocol,
336                                      StringRef prefix,
337                                      StringRef ClassName,
338                                      std::string &Result) = 0;
339     virtual void RewriteObjCClassMetaData(ObjCImplementationDecl *IDecl,
340                                           std::string &Result) = 0;
341 
342     // Rewriting ivar access
343     virtual Stmt *RewriteObjCIvarRefExpr(ObjCIvarRefExpr *IV) = 0;
344     virtual void RewriteIvarOffsetComputation(ObjCIvarDecl *ivar,
345                                          std::string &Result) = 0;
346 
347     // Misc. AST transformation routines. Sometimes they end up calling
348     // rewriting routines on the new ASTs.
349     CallExpr *SynthesizeCallToFunctionDecl(FunctionDecl *FD,
350                                            ArrayRef<Expr *> Args,
351                                            SourceLocation StartLoc=SourceLocation(),
352                                            SourceLocation EndLoc=SourceLocation());
353     CallExpr *SynthMsgSendStretCallExpr(FunctionDecl *MsgSendStretFlavor,
354                                         QualType msgSendType,
355                                         QualType returnType,
356                                         SmallVectorImpl<QualType> &ArgTypes,
357                                         SmallVectorImpl<Expr*> &MsgExprs,
358                                         ObjCMethodDecl *Method);
359     Stmt *SynthMessageExpr(ObjCMessageExpr *Exp,
360                            SourceLocation StartLoc=SourceLocation(),
361                            SourceLocation EndLoc=SourceLocation());
362 
363     void SynthCountByEnumWithState(std::string &buf);
364     void SynthMsgSendFunctionDecl();
365     void SynthMsgSendSuperFunctionDecl();
366     void SynthMsgSendStretFunctionDecl();
367     void SynthMsgSendFpretFunctionDecl();
368     void SynthMsgSendSuperStretFunctionDecl();
369     void SynthGetClassFunctionDecl();
370     void SynthGetMetaClassFunctionDecl();
371     void SynthGetSuperClassFunctionDecl();
372     void SynthSelGetUidFunctionDecl();
373     void SynthSuperConstructorFunctionDecl();
374 
375     std::string SynthesizeByrefCopyDestroyHelper(VarDecl *VD, int flag);
376     std::string SynthesizeBlockHelperFuncs(BlockExpr *CE, int i,
377                                       StringRef funcName, std::string Tag);
378     std::string SynthesizeBlockFunc(BlockExpr *CE, int i,
379                                       StringRef funcName, std::string Tag);
380     std::string SynthesizeBlockImpl(BlockExpr *CE,
381                                     std::string Tag, std::string Desc);
382     std::string SynthesizeBlockDescriptor(std::string DescTag,
383                                           std::string ImplTag,
384                                           int i, StringRef funcName,
385                                           unsigned hasCopy);
386     Stmt *SynthesizeBlockCall(CallExpr *Exp, const Expr* BlockExp);
387     void SynthesizeBlockLiterals(SourceLocation FunLocStart,
388                                  StringRef FunName);
389     FunctionDecl *SynthBlockInitFunctionDecl(StringRef name);
390     Stmt *SynthBlockInitExpr(BlockExpr *Exp,
391             const SmallVectorImpl<DeclRefExpr *> &InnerBlockDeclRefs);
392 
393     // Misc. helper routines.
394     QualType getProtocolType();
395     void WarnAboutReturnGotoStmts(Stmt *S);
396     void HasReturnStmts(Stmt *S, bool &hasReturns);
397     void CheckFunctionPointerDecl(QualType dType, NamedDecl *ND);
398     void InsertBlockLiteralsWithinFunction(FunctionDecl *FD);
399     void InsertBlockLiteralsWithinMethod(ObjCMethodDecl *MD);
400 
401     bool IsDeclStmtInForeachHeader(DeclStmt *DS);
402     void CollectBlockDeclRefInfo(BlockExpr *Exp);
403     void GetBlockDeclRefExprs(Stmt *S);
404     void GetInnerBlockDeclRefExprs(Stmt *S,
405                 SmallVectorImpl<DeclRefExpr *> &InnerBlockDeclRefs,
406                 llvm::SmallPtrSetImpl<const DeclContext *> &InnerContexts);
407 
408     // We avoid calling Type::isBlockPointerType(), since it operates on the
409     // canonical type. We only care if the top-level type is a closure pointer.
410     bool isTopLevelBlockPointerType(QualType T) {
411       return isa<BlockPointerType>(T);
412     }
413 
414     /// convertBlockPointerToFunctionPointer - Converts a block-pointer type
415     /// to a function pointer type and upon success, returns true; false
416     /// otherwise.
417     bool convertBlockPointerToFunctionPointer(QualType &T) {
418       if (isTopLevelBlockPointerType(T)) {
419         const auto *BPT = T->castAs<BlockPointerType>();
420         T = Context->getPointerType(BPT->getPointeeType());
421         return true;
422       }
423       return false;
424     }
425 
426     bool needToScanForQualifiers(QualType T);
427     QualType getSuperStructType();
428     QualType getConstantStringStructType();
429     QualType convertFunctionTypeOfBlocks(const FunctionType *FT);
430     bool BufferContainsPPDirectives(const char *startBuf, const char *endBuf);
431 
432     void convertToUnqualifiedObjCType(QualType &T) {
433       if (T->isObjCQualifiedIdType())
434         T = Context->getObjCIdType();
435       else if (T->isObjCQualifiedClassType())
436         T = Context->getObjCClassType();
437       else if (T->isObjCObjectPointerType() &&
438                T->getPointeeType()->isObjCQualifiedInterfaceType()) {
439         if (const ObjCObjectPointerType * OBJPT =
440               T->getAsObjCInterfacePointerType()) {
441           const ObjCInterfaceType *IFaceT = OBJPT->getInterfaceType();
442           T = QualType(IFaceT, 0);
443           T = Context->getPointerType(T);
444         }
445      }
446     }
447 
448     // FIXME: This predicate seems like it would be useful to add to ASTContext.
449     bool isObjCType(QualType T) {
450       if (!LangOpts.ObjC)
451         return false;
452 
453       QualType OCT = Context->getCanonicalType(T).getUnqualifiedType();
454 
455       if (OCT == Context->getCanonicalType(Context->getObjCIdType()) ||
456           OCT == Context->getCanonicalType(Context->getObjCClassType()))
457         return true;
458 
459       if (const PointerType *PT = OCT->getAs<PointerType>()) {
460         if (isa<ObjCInterfaceType>(PT->getPointeeType()) ||
461             PT->getPointeeType()->isObjCQualifiedIdType())
462           return true;
463       }
464       return false;
465     }
466     bool PointerTypeTakesAnyBlockArguments(QualType QT);
467     bool PointerTypeTakesAnyObjCQualifiedType(QualType QT);
468     void GetExtentOfArgList(const char *Name, const char *&LParen,
469                             const char *&RParen);
470 
471     void QuoteDoublequotes(std::string &From, std::string &To) {
472       for (unsigned i = 0; i < From.length(); i++) {
473         if (From[i] == '"')
474           To += "\\\"";
475         else
476           To += From[i];
477       }
478     }
479 
480     QualType getSimpleFunctionType(QualType result,
481                                    ArrayRef<QualType> args,
482                                    bool variadic = false) {
483       if (result == Context->getObjCInstanceType())
484         result =  Context->getObjCIdType();
485       FunctionProtoType::ExtProtoInfo fpi;
486       fpi.Variadic = variadic;
487       return Context->getFunctionType(result, args, fpi);
488     }
489 
490     // Helper function: create a CStyleCastExpr with trivial type source info.
491     CStyleCastExpr* NoTypeInfoCStyleCastExpr(ASTContext *Ctx, QualType Ty,
492                                              CastKind Kind, Expr *E) {
493       TypeSourceInfo *TInfo = Ctx->getTrivialTypeSourceInfo(Ty, SourceLocation());
494       return CStyleCastExpr::Create(*Ctx, Ty, VK_RValue, Kind, E, nullptr,
495                                     TInfo, SourceLocation(), SourceLocation());
496     }
497 
498     StringLiteral *getStringLiteral(StringRef Str) {
499       QualType StrType = Context->getConstantArrayType(
500           Context->CharTy, llvm::APInt(32, Str.size() + 1), nullptr,
501           ArrayType::Normal, 0);
502       return StringLiteral::Create(*Context, Str, StringLiteral::Ascii,
503                                    /*Pascal=*/false, StrType, SourceLocation());
504     }
505   };
506 
507   class RewriteObjCFragileABI : public RewriteObjC {
508   public:
509     RewriteObjCFragileABI(std::string inFile, std::unique_ptr<raw_ostream> OS,
510                           DiagnosticsEngine &D, const LangOptions &LOpts,
511                           bool silenceMacroWarn)
512         : RewriteObjC(inFile, std::move(OS), D, LOpts, silenceMacroWarn) {}
513 
514     ~RewriteObjCFragileABI() override {}
515     void Initialize(ASTContext &context) override;
516 
517     // Rewriting metadata
518     template<typename MethodIterator>
519     void RewriteObjCMethodsMetaData(MethodIterator MethodBegin,
520                                     MethodIterator MethodEnd,
521                                     bool IsInstanceMethod,
522                                     StringRef prefix,
523                                     StringRef ClassName,
524                                     std::string &Result);
525     void RewriteObjCProtocolMetaData(ObjCProtocolDecl *Protocol,
526                                      StringRef prefix, StringRef ClassName,
527                                      std::string &Result) override;
528     void RewriteObjCProtocolListMetaData(
529           const ObjCList<ObjCProtocolDecl> &Prots,
530           StringRef prefix, StringRef ClassName, std::string &Result) override;
531     void RewriteObjCClassMetaData(ObjCImplementationDecl *IDecl,
532                                   std::string &Result) override;
533     void RewriteMetaDataIntoBuffer(std::string &Result) override;
534     void RewriteObjCCategoryImplDecl(ObjCCategoryImplDecl *CDecl,
535                                      std::string &Result) override;
536 
537     // Rewriting ivar
538     void RewriteIvarOffsetComputation(ObjCIvarDecl *ivar,
539                                       std::string &Result) override;
540     Stmt *RewriteObjCIvarRefExpr(ObjCIvarRefExpr *IV) override;
541   };
542 } // end anonymous namespace
543 
544 void RewriteObjC::RewriteBlocksInFunctionProtoType(QualType funcType,
545                                                    NamedDecl *D) {
546   if (const FunctionProtoType *fproto
547       = dyn_cast<FunctionProtoType>(funcType.IgnoreParens())) {
548     for (const auto &I : fproto->param_types())
549       if (isTopLevelBlockPointerType(I)) {
550         // All the args are checked/rewritten. Don't call twice!
551         RewriteBlockPointerDecl(D);
552         break;
553       }
554   }
555 }
556 
557 void RewriteObjC::CheckFunctionPointerDecl(QualType funcType, NamedDecl *ND) {
558   const PointerType *PT = funcType->getAs<PointerType>();
559   if (PT && PointerTypeTakesAnyBlockArguments(funcType))
560     RewriteBlocksInFunctionProtoType(PT->getPointeeType(), ND);
561 }
562 
563 static bool IsHeaderFile(const std::string &Filename) {
564   std::string::size_type DotPos = Filename.rfind('.');
565 
566   if (DotPos == std::string::npos) {
567     // no file extension
568     return false;
569   }
570 
571   std::string Ext = std::string(Filename.begin()+DotPos+1, Filename.end());
572   // C header: .h
573   // C++ header: .hh or .H;
574   return Ext == "h" || Ext == "hh" || Ext == "H";
575 }
576 
577 RewriteObjC::RewriteObjC(std::string inFile, std::unique_ptr<raw_ostream> OS,
578                          DiagnosticsEngine &D, const LangOptions &LOpts,
579                          bool silenceMacroWarn)
580     : Diags(D), LangOpts(LOpts), InFileName(inFile), OutFile(std::move(OS)),
581       SilenceRewriteMacroWarning(silenceMacroWarn) {
582   IsHeader = IsHeaderFile(inFile);
583   RewriteFailedDiag = Diags.getCustomDiagID(DiagnosticsEngine::Warning,
584                "rewriting sub-expression within a macro (may not be correct)");
585   TryFinallyContainsReturnDiag = Diags.getCustomDiagID(
586                DiagnosticsEngine::Warning,
587                "rewriter doesn't support user-specified control flow semantics "
588                "for @try/@finally (code may not execute properly)");
589 }
590 
591 std::unique_ptr<ASTConsumer>
592 clang::CreateObjCRewriter(const std::string &InFile,
593                           std::unique_ptr<raw_ostream> OS,
594                           DiagnosticsEngine &Diags, const LangOptions &LOpts,
595                           bool SilenceRewriteMacroWarning) {
596   return std::make_unique<RewriteObjCFragileABI>(
597       InFile, std::move(OS), Diags, LOpts, SilenceRewriteMacroWarning);
598 }
599 
600 void RewriteObjC::InitializeCommon(ASTContext &context) {
601   Context = &context;
602   SM = &Context->getSourceManager();
603   TUDecl = Context->getTranslationUnitDecl();
604   MsgSendFunctionDecl = nullptr;
605   MsgSendSuperFunctionDecl = nullptr;
606   MsgSendStretFunctionDecl = nullptr;
607   MsgSendSuperStretFunctionDecl = nullptr;
608   MsgSendFpretFunctionDecl = nullptr;
609   GetClassFunctionDecl = nullptr;
610   GetMetaClassFunctionDecl = nullptr;
611   GetSuperClassFunctionDecl = nullptr;
612   SelGetUidFunctionDecl = nullptr;
613   CFStringFunctionDecl = nullptr;
614   ConstantStringClassReference = nullptr;
615   NSStringRecord = nullptr;
616   CurMethodDef = nullptr;
617   CurFunctionDef = nullptr;
618   CurFunctionDeclToDeclareForBlock = nullptr;
619   GlobalVarDecl = nullptr;
620   SuperStructDecl = nullptr;
621   ProtocolTypeDecl = nullptr;
622   ConstantStringDecl = nullptr;
623   BcLabelCount = 0;
624   SuperConstructorFunctionDecl = nullptr;
625   NumObjCStringLiterals = 0;
626   PropParentMap = nullptr;
627   CurrentBody = nullptr;
628   DisableReplaceStmt = false;
629   objc_impl_method = false;
630 
631   // Get the ID and start/end of the main file.
632   MainFileID = SM->getMainFileID();
633   const llvm::MemoryBuffer *MainBuf = SM->getBuffer(MainFileID);
634   MainFileStart = MainBuf->getBufferStart();
635   MainFileEnd = MainBuf->getBufferEnd();
636 
637   Rewrite.setSourceMgr(Context->getSourceManager(), Context->getLangOpts());
638 }
639 
640 //===----------------------------------------------------------------------===//
641 // Top Level Driver Code
642 //===----------------------------------------------------------------------===//
643 
644 void RewriteObjC::HandleTopLevelSingleDecl(Decl *D) {
645   if (Diags.hasErrorOccurred())
646     return;
647 
648   // Two cases: either the decl could be in the main file, or it could be in a
649   // #included file.  If the former, rewrite it now.  If the later, check to see
650   // if we rewrote the #include/#import.
651   SourceLocation Loc = D->getLocation();
652   Loc = SM->getExpansionLoc(Loc);
653 
654   // If this is for a builtin, ignore it.
655   if (Loc.isInvalid()) return;
656 
657   // Look for built-in declarations that we need to refer during the rewrite.
658   if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
659     RewriteFunctionDecl(FD);
660   } else if (VarDecl *FVD = dyn_cast<VarDecl>(D)) {
661     // declared in <Foundation/NSString.h>
662     if (FVD->getName() == "_NSConstantStringClassReference") {
663       ConstantStringClassReference = FVD;
664       return;
665     }
666   } else if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(D)) {
667     if (ID->isThisDeclarationADefinition())
668       RewriteInterfaceDecl(ID);
669   } else if (ObjCCategoryDecl *CD = dyn_cast<ObjCCategoryDecl>(D)) {
670     RewriteCategoryDecl(CD);
671   } else if (ObjCProtocolDecl *PD = dyn_cast<ObjCProtocolDecl>(D)) {
672     if (PD->isThisDeclarationADefinition())
673       RewriteProtocolDecl(PD);
674   } else if (LinkageSpecDecl *LSD = dyn_cast<LinkageSpecDecl>(D)) {
675     // Recurse into linkage specifications
676     for (DeclContext::decl_iterator DI = LSD->decls_begin(),
677                                  DIEnd = LSD->decls_end();
678          DI != DIEnd; ) {
679       if (ObjCInterfaceDecl *IFace = dyn_cast<ObjCInterfaceDecl>((*DI))) {
680         if (!IFace->isThisDeclarationADefinition()) {
681           SmallVector<Decl *, 8> DG;
682           SourceLocation StartLoc = IFace->getBeginLoc();
683           do {
684             if (isa<ObjCInterfaceDecl>(*DI) &&
685                 !cast<ObjCInterfaceDecl>(*DI)->isThisDeclarationADefinition() &&
686                 StartLoc == (*DI)->getBeginLoc())
687               DG.push_back(*DI);
688             else
689               break;
690 
691             ++DI;
692           } while (DI != DIEnd);
693           RewriteForwardClassDecl(DG);
694           continue;
695         }
696       }
697 
698       if (ObjCProtocolDecl *Proto = dyn_cast<ObjCProtocolDecl>((*DI))) {
699         if (!Proto->isThisDeclarationADefinition()) {
700           SmallVector<Decl *, 8> DG;
701           SourceLocation StartLoc = Proto->getBeginLoc();
702           do {
703             if (isa<ObjCProtocolDecl>(*DI) &&
704                 !cast<ObjCProtocolDecl>(*DI)->isThisDeclarationADefinition() &&
705                 StartLoc == (*DI)->getBeginLoc())
706               DG.push_back(*DI);
707             else
708               break;
709 
710             ++DI;
711           } while (DI != DIEnd);
712           RewriteForwardProtocolDecl(DG);
713           continue;
714         }
715       }
716 
717       HandleTopLevelSingleDecl(*DI);
718       ++DI;
719     }
720   }
721   // If we have a decl in the main file, see if we should rewrite it.
722   if (SM->isWrittenInMainFile(Loc))
723     return HandleDeclInMainFile(D);
724 }
725 
726 //===----------------------------------------------------------------------===//
727 // Syntactic (non-AST) Rewriting Code
728 //===----------------------------------------------------------------------===//
729 
730 void RewriteObjC::RewriteInclude() {
731   SourceLocation LocStart = SM->getLocForStartOfFile(MainFileID);
732   StringRef MainBuf = SM->getBufferData(MainFileID);
733   const char *MainBufStart = MainBuf.begin();
734   const char *MainBufEnd = MainBuf.end();
735   size_t ImportLen = strlen("import");
736 
737   // Loop over the whole file, looking for includes.
738   for (const char *BufPtr = MainBufStart; BufPtr < MainBufEnd; ++BufPtr) {
739     if (*BufPtr == '#') {
740       if (++BufPtr == MainBufEnd)
741         return;
742       while (*BufPtr == ' ' || *BufPtr == '\t')
743         if (++BufPtr == MainBufEnd)
744           return;
745       if (!strncmp(BufPtr, "import", ImportLen)) {
746         // replace import with include
747         SourceLocation ImportLoc =
748           LocStart.getLocWithOffset(BufPtr-MainBufStart);
749         ReplaceText(ImportLoc, ImportLen, "include");
750         BufPtr += ImportLen;
751       }
752     }
753   }
754 }
755 
756 static std::string getIvarAccessString(ObjCIvarDecl *OID) {
757   const ObjCInterfaceDecl *ClassDecl = OID->getContainingInterface();
758   std::string S;
759   S = "((struct ";
760   S += ClassDecl->getIdentifier()->getName();
761   S += "_IMPL *)self)->";
762   S += OID->getName();
763   return S;
764 }
765 
766 void RewriteObjC::RewritePropertyImplDecl(ObjCPropertyImplDecl *PID,
767                                           ObjCImplementationDecl *IMD,
768                                           ObjCCategoryImplDecl *CID) {
769   static bool objcGetPropertyDefined = false;
770   static bool objcSetPropertyDefined = false;
771   SourceLocation startLoc = PID->getBeginLoc();
772   InsertText(startLoc, "// ");
773   const char *startBuf = SM->getCharacterData(startLoc);
774   assert((*startBuf == '@') && "bogus @synthesize location");
775   const char *semiBuf = strchr(startBuf, ';');
776   assert((*semiBuf == ';') && "@synthesize: can't find ';'");
777   SourceLocation onePastSemiLoc =
778     startLoc.getLocWithOffset(semiBuf-startBuf+1);
779 
780   if (PID->getPropertyImplementation() == ObjCPropertyImplDecl::Dynamic)
781     return; // FIXME: is this correct?
782 
783   // Generate the 'getter' function.
784   ObjCPropertyDecl *PD = PID->getPropertyDecl();
785   ObjCIvarDecl *OID = PID->getPropertyIvarDecl();
786 
787   if (!OID)
788     return;
789 
790   unsigned Attributes = PD->getPropertyAttributes();
791   if (PID->getGetterMethodDecl() && !PID->getGetterMethodDecl()->isDefined()) {
792     bool GenGetProperty = !(Attributes & ObjCPropertyDecl::OBJC_PR_nonatomic) &&
793                           (Attributes & (ObjCPropertyDecl::OBJC_PR_retain |
794                                          ObjCPropertyDecl::OBJC_PR_copy));
795     std::string Getr;
796     if (GenGetProperty && !objcGetPropertyDefined) {
797       objcGetPropertyDefined = true;
798       // FIXME. Is this attribute correct in all cases?
799       Getr = "\nextern \"C\" __declspec(dllimport) "
800             "id objc_getProperty(id, SEL, long, bool);\n";
801     }
802     RewriteObjCMethodDecl(OID->getContainingInterface(),
803                           PID->getGetterMethodDecl(), Getr);
804     Getr += "{ ";
805     // Synthesize an explicit cast to gain access to the ivar.
806     // See objc-act.c:objc_synthesize_new_getter() for details.
807     if (GenGetProperty) {
808       // return objc_getProperty(self, _cmd, offsetof(ClassDecl, OID), 1)
809       Getr += "typedef ";
810       const FunctionType *FPRetType = nullptr;
811       RewriteTypeIntoString(PID->getGetterMethodDecl()->getReturnType(), Getr,
812                             FPRetType);
813       Getr += " _TYPE";
814       if (FPRetType) {
815         Getr += ")"; // close the precedence "scope" for "*".
816 
817         // Now, emit the argument types (if any).
818         if (const FunctionProtoType *FT = dyn_cast<FunctionProtoType>(FPRetType)){
819           Getr += "(";
820           for (unsigned i = 0, e = FT->getNumParams(); i != e; ++i) {
821             if (i) Getr += ", ";
822             std::string ParamStr =
823                 FT->getParamType(i).getAsString(Context->getPrintingPolicy());
824             Getr += ParamStr;
825           }
826           if (FT->isVariadic()) {
827             if (FT->getNumParams())
828               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() || !PID->getSetterMethodDecl() ||
848       PID->getSetterMethodDecl()->isDefined())
849     return;
850 
851   // Generate the 'setter' function.
852   std::string Setr;
853   bool GenSetProperty = Attributes & (ObjCPropertyDecl::OBJC_PR_retain |
854                                       ObjCPropertyDecl::OBJC_PR_copy);
855   if (GenSetProperty && !objcSetPropertyDefined) {
856     objcSetPropertyDefined = true;
857     // FIXME. Is this attribute correct in all cases?
858     Setr = "\nextern \"C\" __declspec(dllimport) "
859     "void objc_setProperty (id, SEL, long, id, bool, bool);\n";
860   }
861 
862   RewriteObjCMethodDecl(OID->getContainingInterface(),
863                         PID->getSetterMethodDecl(), Setr);
864   Setr += "{ ";
865   // Synthesize an explicit cast to initialize the ivar.
866   // See objc-act.c:objc_synthesize_new_setter() for details.
867   if (GenSetProperty) {
868     Setr += "objc_setProperty (self, _cmd, ";
869     RewriteIvarOffsetComputation(OID, Setr);
870     Setr += ", (id)";
871     Setr += PD->getName();
872     Setr += ", ";
873     if (Attributes & ObjCPropertyDecl::OBJC_PR_nonatomic)
874       Setr += "0, ";
875     else
876       Setr += "1, ";
877     if (Attributes & ObjCPropertyDecl::OBJC_PR_copy)
878       Setr += "1)";
879     else
880       Setr += "0)";
881   }
882   else {
883     Setr += getIvarAccessString(OID) + " = ";
884     Setr += PD->getName();
885   }
886   Setr += "; }";
887   InsertText(onePastSemiLoc, Setr);
888 }
889 
890 static void RewriteOneForwardClassDecl(ObjCInterfaceDecl *ForwardDecl,
891                                        std::string &typedefString) {
892   typedefString += "#ifndef _REWRITER_typedef_";
893   typedefString += ForwardDecl->getNameAsString();
894   typedefString += "\n";
895   typedefString += "#define _REWRITER_typedef_";
896   typedefString += ForwardDecl->getNameAsString();
897   typedefString += "\n";
898   typedefString += "typedef struct objc_object ";
899   typedefString += ForwardDecl->getNameAsString();
900   typedefString += ";\n#endif\n";
901 }
902 
903 void RewriteObjC::RewriteForwardClassEpilogue(ObjCInterfaceDecl *ClassDecl,
904                                               const std::string &typedefString) {
905   SourceLocation startLoc = ClassDecl->getBeginLoc();
906   const char *startBuf = SM->getCharacterData(startLoc);
907   const char *semiPtr = strchr(startBuf, ';');
908   // Replace the @class with typedefs corresponding to the classes.
909   ReplaceText(startLoc, semiPtr - startBuf + 1, typedefString);
910 }
911 
912 void RewriteObjC::RewriteForwardClassDecl(DeclGroupRef D) {
913   std::string typedefString;
914   for (DeclGroupRef::iterator I = D.begin(), E = D.end(); I != E; ++I) {
915     ObjCInterfaceDecl *ForwardDecl = cast<ObjCInterfaceDecl>(*I);
916     if (I == D.begin()) {
917       // Translate to typedef's that forward reference structs with the same name
918       // as the class. As a convenience, we include the original declaration
919       // as a comment.
920       typedefString += "// @class ";
921       typedefString += ForwardDecl->getNameAsString();
922       typedefString += ";\n";
923     }
924     RewriteOneForwardClassDecl(ForwardDecl, typedefString);
925   }
926   DeclGroupRef::iterator I = D.begin();
927   RewriteForwardClassEpilogue(cast<ObjCInterfaceDecl>(*I), typedefString);
928 }
929 
930 void RewriteObjC::RewriteForwardClassDecl(const SmallVectorImpl<Decl *> &D) {
931   std::string typedefString;
932   for (unsigned i = 0; i < D.size(); i++) {
933     ObjCInterfaceDecl *ForwardDecl = cast<ObjCInterfaceDecl>(D[i]);
934     if (i == 0) {
935       typedefString += "// @class ";
936       typedefString += ForwardDecl->getNameAsString();
937       typedefString += ";\n";
938     }
939     RewriteOneForwardClassDecl(ForwardDecl, typedefString);
940   }
941   RewriteForwardClassEpilogue(cast<ObjCInterfaceDecl>(D[0]), typedefString);
942 }
943 
944 void RewriteObjC::RewriteMethodDeclaration(ObjCMethodDecl *Method) {
945   // When method is a synthesized one, such as a getter/setter there is
946   // nothing to rewrite.
947   if (Method->isImplicit())
948     return;
949   SourceLocation LocStart = Method->getBeginLoc();
950   SourceLocation LocEnd = Method->getEndLoc();
951 
952   if (SM->getExpansionLineNumber(LocEnd) >
953       SM->getExpansionLineNumber(LocStart)) {
954     InsertText(LocStart, "#if 0\n");
955     ReplaceText(LocEnd, 1, ";\n#endif\n");
956   } else {
957     InsertText(LocStart, "// ");
958   }
959 }
960 
961 void RewriteObjC::RewriteProperty(ObjCPropertyDecl *prop) {
962   SourceLocation Loc = prop->getAtLoc();
963 
964   ReplaceText(Loc, 0, "// ");
965   // FIXME: handle properties that are declared across multiple lines.
966 }
967 
968 void RewriteObjC::RewriteCategoryDecl(ObjCCategoryDecl *CatDecl) {
969   SourceLocation LocStart = CatDecl->getBeginLoc();
970 
971   // FIXME: handle category headers that are declared across multiple lines.
972   ReplaceText(LocStart, 0, "// ");
973 
974   for (auto *I : CatDecl->instance_properties())
975     RewriteProperty(I);
976   for (auto *I : CatDecl->instance_methods())
977     RewriteMethodDeclaration(I);
978   for (auto *I : CatDecl->class_methods())
979     RewriteMethodDeclaration(I);
980 
981   // Lastly, comment out the @end.
982   ReplaceText(CatDecl->getAtEndRange().getBegin(),
983               strlen("@end"), "/* @end */");
984 }
985 
986 void RewriteObjC::RewriteProtocolDecl(ObjCProtocolDecl *PDecl) {
987   SourceLocation LocStart = PDecl->getBeginLoc();
988   assert(PDecl->isThisDeclarationADefinition());
989 
990   // FIXME: handle protocol headers that are declared across multiple lines.
991   ReplaceText(LocStart, 0, "// ");
992 
993   for (auto *I : PDecl->instance_methods())
994     RewriteMethodDeclaration(I);
995   for (auto *I : PDecl->class_methods())
996     RewriteMethodDeclaration(I);
997   for (auto *I : PDecl->instance_properties())
998     RewriteProperty(I);
999 
1000   // Lastly, comment out the @end.
1001   SourceLocation LocEnd = PDecl->getAtEndRange().getBegin();
1002   ReplaceText(LocEnd, strlen("@end"), "/* @end */");
1003 
1004   // Must comment out @optional/@required
1005   const char *startBuf = SM->getCharacterData(LocStart);
1006   const char *endBuf = SM->getCharacterData(LocEnd);
1007   for (const char *p = startBuf; p < endBuf; p++) {
1008     if (*p == '@' && !strncmp(p+1, "optional", strlen("optional"))) {
1009       SourceLocation OptionalLoc = LocStart.getLocWithOffset(p-startBuf);
1010       ReplaceText(OptionalLoc, strlen("@optional"), "/* @optional */");
1011 
1012     }
1013     else if (*p == '@' && !strncmp(p+1, "required", strlen("required"))) {
1014       SourceLocation OptionalLoc = LocStart.getLocWithOffset(p-startBuf);
1015       ReplaceText(OptionalLoc, strlen("@required"), "/* @required */");
1016 
1017     }
1018   }
1019 }
1020 
1021 void RewriteObjC::RewriteForwardProtocolDecl(DeclGroupRef D) {
1022   SourceLocation LocStart = (*D.begin())->getBeginLoc();
1023   if (LocStart.isInvalid())
1024     llvm_unreachable("Invalid SourceLocation");
1025   // FIXME: handle forward protocol that are declared across multiple lines.
1026   ReplaceText(LocStart, 0, "// ");
1027 }
1028 
1029 void
1030 RewriteObjC::RewriteForwardProtocolDecl(const SmallVectorImpl<Decl *> &DG) {
1031   SourceLocation LocStart = DG[0]->getBeginLoc();
1032   if (LocStart.isInvalid())
1033     llvm_unreachable("Invalid SourceLocation");
1034   // FIXME: handle forward protocol that are declared across multiple lines.
1035   ReplaceText(LocStart, 0, "// ");
1036 }
1037 
1038 void RewriteObjC::RewriteTypeIntoString(QualType T, std::string &ResultStr,
1039                                         const FunctionType *&FPRetType) {
1040   if (T->isObjCQualifiedIdType())
1041     ResultStr += "id";
1042   else if (T->isFunctionPointerType() ||
1043            T->isBlockPointerType()) {
1044     // needs special handling, since pointer-to-functions have special
1045     // syntax (where a decaration models use).
1046     QualType retType = T;
1047     QualType PointeeTy;
1048     if (const PointerType* PT = retType->getAs<PointerType>())
1049       PointeeTy = PT->getPointeeType();
1050     else if (const BlockPointerType *BPT = retType->getAs<BlockPointerType>())
1051       PointeeTy = BPT->getPointeeType();
1052     if ((FPRetType = PointeeTy->getAs<FunctionType>())) {
1053       ResultStr +=
1054           FPRetType->getReturnType().getAsString(Context->getPrintingPolicy());
1055       ResultStr += "(*";
1056     }
1057   } else
1058     ResultStr += T.getAsString(Context->getPrintingPolicy());
1059 }
1060 
1061 void RewriteObjC::RewriteObjCMethodDecl(const ObjCInterfaceDecl *IDecl,
1062                                         ObjCMethodDecl *OMD,
1063                                         std::string &ResultStr) {
1064   //fprintf(stderr,"In RewriteObjCMethodDecl\n");
1065   const FunctionType *FPRetType = nullptr;
1066   ResultStr += "\nstatic ";
1067   RewriteTypeIntoString(OMD->getReturnType(), ResultStr, FPRetType);
1068   ResultStr += " ";
1069 
1070   // Unique method name
1071   std::string NameStr;
1072 
1073   if (OMD->isInstanceMethod())
1074     NameStr += "_I_";
1075   else
1076     NameStr += "_C_";
1077 
1078   NameStr += IDecl->getNameAsString();
1079   NameStr += "_";
1080 
1081   if (ObjCCategoryImplDecl *CID =
1082       dyn_cast<ObjCCategoryImplDecl>(OMD->getDeclContext())) {
1083     NameStr += CID->getNameAsString();
1084     NameStr += "_";
1085   }
1086   // Append selector names, replacing ':' with '_'
1087   {
1088     std::string selString = OMD->getSelector().getAsString();
1089     int len = selString.size();
1090     for (int i = 0; i < len; i++)
1091       if (selString[i] == ':')
1092         selString[i] = '_';
1093     NameStr += selString;
1094   }
1095   // Remember this name for metadata emission
1096   MethodInternalNames[OMD] = NameStr;
1097   ResultStr += NameStr;
1098 
1099   // Rewrite arguments
1100   ResultStr += "(";
1101 
1102   // invisible arguments
1103   if (OMD->isInstanceMethod()) {
1104     QualType selfTy = Context->getObjCInterfaceType(IDecl);
1105     selfTy = Context->getPointerType(selfTy);
1106     if (!LangOpts.MicrosoftExt) {
1107       if (ObjCSynthesizedStructs.count(const_cast<ObjCInterfaceDecl*>(IDecl)))
1108         ResultStr += "struct ";
1109     }
1110     // When rewriting for Microsoft, explicitly omit the structure name.
1111     ResultStr += IDecl->getNameAsString();
1112     ResultStr += " *";
1113   }
1114   else
1115     ResultStr += Context->getObjCClassType().getAsString(
1116       Context->getPrintingPolicy());
1117 
1118   ResultStr += " self, ";
1119   ResultStr += Context->getObjCSelType().getAsString(Context->getPrintingPolicy());
1120   ResultStr += " _cmd";
1121 
1122   // Method arguments.
1123   for (const auto *PDecl : OMD->parameters()) {
1124     ResultStr += ", ";
1125     if (PDecl->getType()->isObjCQualifiedIdType()) {
1126       ResultStr += "id ";
1127       ResultStr += PDecl->getNameAsString();
1128     } else {
1129       std::string Name = PDecl->getNameAsString();
1130       QualType QT = PDecl->getType();
1131       // Make sure we convert "t (^)(...)" to "t (*)(...)".
1132       (void)convertBlockPointerToFunctionPointer(QT);
1133       QT.getAsStringInternal(Name, Context->getPrintingPolicy());
1134       ResultStr += Name;
1135     }
1136   }
1137   if (OMD->isVariadic())
1138     ResultStr += ", ...";
1139   ResultStr += ") ";
1140 
1141   if (FPRetType) {
1142     ResultStr += ")"; // close the precedence "scope" for "*".
1143 
1144     // Now, emit the argument types (if any).
1145     if (const FunctionProtoType *FT = dyn_cast<FunctionProtoType>(FPRetType)) {
1146       ResultStr += "(";
1147       for (unsigned i = 0, e = FT->getNumParams(); i != e; ++i) {
1148         if (i) ResultStr += ", ";
1149         std::string ParamStr =
1150             FT->getParamType(i).getAsString(Context->getPrintingPolicy());
1151         ResultStr += ParamStr;
1152       }
1153       if (FT->isVariadic()) {
1154         if (FT->getNumParams())
1155           ResultStr += ", ";
1156         ResultStr += "...";
1157       }
1158       ResultStr += ")";
1159     } else {
1160       ResultStr += "()";
1161     }
1162   }
1163 }
1164 
1165 void RewriteObjC::RewriteImplementationDecl(Decl *OID) {
1166   ObjCImplementationDecl *IMD = dyn_cast<ObjCImplementationDecl>(OID);
1167   ObjCCategoryImplDecl *CID = dyn_cast<ObjCCategoryImplDecl>(OID);
1168   assert((IMD || CID) && "Unknown ImplementationDecl");
1169 
1170   InsertText(IMD ? IMD->getBeginLoc() : CID->getBeginLoc(), "// ");
1171 
1172   for (auto *OMD : IMD ? IMD->instance_methods() : CID->instance_methods()) {
1173     if (!OMD->getBody())
1174       continue;
1175     std::string ResultStr;
1176     RewriteObjCMethodDecl(OMD->getClassInterface(), OMD, ResultStr);
1177     SourceLocation LocStart = OMD->getBeginLoc();
1178     SourceLocation LocEnd = OMD->getCompoundBody()->getBeginLoc();
1179 
1180     const char *startBuf = SM->getCharacterData(LocStart);
1181     const char *endBuf = SM->getCharacterData(LocEnd);
1182     ReplaceText(LocStart, endBuf-startBuf, ResultStr);
1183   }
1184 
1185   for (auto *OMD : IMD ? IMD->class_methods() : CID->class_methods()) {
1186     if (!OMD->getBody())
1187       continue;
1188     std::string ResultStr;
1189     RewriteObjCMethodDecl(OMD->getClassInterface(), OMD, ResultStr);
1190     SourceLocation LocStart = OMD->getBeginLoc();
1191     SourceLocation LocEnd = OMD->getCompoundBody()->getBeginLoc();
1192 
1193     const char *startBuf = SM->getCharacterData(LocStart);
1194     const char *endBuf = SM->getCharacterData(LocEnd);
1195     ReplaceText(LocStart, endBuf-startBuf, ResultStr);
1196   }
1197   for (auto *I : IMD ? IMD->property_impls() : CID->property_impls())
1198     RewritePropertyImplDecl(I, IMD, CID);
1199 
1200   InsertText(IMD ? IMD->getEndLoc() : CID->getEndLoc(), "// ");
1201 }
1202 
1203 void RewriteObjC::RewriteInterfaceDecl(ObjCInterfaceDecl *ClassDecl) {
1204   std::string ResultStr;
1205   if (!ObjCForwardDecls.count(ClassDecl->getCanonicalDecl())) {
1206     // we haven't seen a forward decl - generate a typedef.
1207     ResultStr = "#ifndef _REWRITER_typedef_";
1208     ResultStr += ClassDecl->getNameAsString();
1209     ResultStr += "\n";
1210     ResultStr += "#define _REWRITER_typedef_";
1211     ResultStr += ClassDecl->getNameAsString();
1212     ResultStr += "\n";
1213     ResultStr += "typedef struct objc_object ";
1214     ResultStr += ClassDecl->getNameAsString();
1215     ResultStr += ";\n#endif\n";
1216     // Mark this typedef as having been generated.
1217     ObjCForwardDecls.insert(ClassDecl->getCanonicalDecl());
1218   }
1219   RewriteObjCInternalStruct(ClassDecl, ResultStr);
1220 
1221   for (auto *I : ClassDecl->instance_properties())
1222     RewriteProperty(I);
1223   for (auto *I : ClassDecl->instance_methods())
1224     RewriteMethodDeclaration(I);
1225   for (auto *I : ClassDecl->class_methods())
1226     RewriteMethodDeclaration(I);
1227 
1228   // Lastly, comment out the @end.
1229   ReplaceText(ClassDecl->getAtEndRange().getBegin(), strlen("@end"),
1230               "/* @end */");
1231 }
1232 
1233 Stmt *RewriteObjC::RewritePropertyOrImplicitSetter(PseudoObjectExpr *PseudoOp) {
1234   SourceRange OldRange = PseudoOp->getSourceRange();
1235 
1236   // We just magically know some things about the structure of this
1237   // expression.
1238   ObjCMessageExpr *OldMsg =
1239     cast<ObjCMessageExpr>(PseudoOp->getSemanticExpr(
1240                             PseudoOp->getNumSemanticExprs() - 1));
1241 
1242   // Because the rewriter doesn't allow us to rewrite rewritten code,
1243   // we need to suppress rewriting the sub-statements.
1244   Expr *Base, *RHS;
1245   {
1246     DisableReplaceStmtScope S(*this);
1247 
1248     // Rebuild the base expression if we have one.
1249     Base = nullptr;
1250     if (OldMsg->getReceiverKind() == ObjCMessageExpr::Instance) {
1251       Base = OldMsg->getInstanceReceiver();
1252       Base = cast<OpaqueValueExpr>(Base)->getSourceExpr();
1253       Base = cast<Expr>(RewriteFunctionBodyOrGlobalInitializer(Base));
1254     }
1255 
1256     // Rebuild the RHS.
1257     RHS = cast<BinaryOperator>(PseudoOp->getSyntacticForm())->getRHS();
1258     RHS = cast<OpaqueValueExpr>(RHS)->getSourceExpr();
1259     RHS = cast<Expr>(RewriteFunctionBodyOrGlobalInitializer(RHS));
1260   }
1261 
1262   // TODO: avoid this copy.
1263   SmallVector<SourceLocation, 1> SelLocs;
1264   OldMsg->getSelectorLocs(SelLocs);
1265 
1266   ObjCMessageExpr *NewMsg = nullptr;
1267   switch (OldMsg->getReceiverKind()) {
1268   case ObjCMessageExpr::Class:
1269     NewMsg = ObjCMessageExpr::Create(*Context, OldMsg->getType(),
1270                                      OldMsg->getValueKind(),
1271                                      OldMsg->getLeftLoc(),
1272                                      OldMsg->getClassReceiverTypeInfo(),
1273                                      OldMsg->getSelector(),
1274                                      SelLocs,
1275                                      OldMsg->getMethodDecl(),
1276                                      RHS,
1277                                      OldMsg->getRightLoc(),
1278                                      OldMsg->isImplicit());
1279     break;
1280 
1281   case ObjCMessageExpr::Instance:
1282     NewMsg = ObjCMessageExpr::Create(*Context, OldMsg->getType(),
1283                                      OldMsg->getValueKind(),
1284                                      OldMsg->getLeftLoc(),
1285                                      Base,
1286                                      OldMsg->getSelector(),
1287                                      SelLocs,
1288                                      OldMsg->getMethodDecl(),
1289                                      RHS,
1290                                      OldMsg->getRightLoc(),
1291                                      OldMsg->isImplicit());
1292     break;
1293 
1294   case ObjCMessageExpr::SuperClass:
1295   case ObjCMessageExpr::SuperInstance:
1296     NewMsg = ObjCMessageExpr::Create(*Context, OldMsg->getType(),
1297                                      OldMsg->getValueKind(),
1298                                      OldMsg->getLeftLoc(),
1299                                      OldMsg->getSuperLoc(),
1300                  OldMsg->getReceiverKind() == ObjCMessageExpr::SuperInstance,
1301                                      OldMsg->getSuperType(),
1302                                      OldMsg->getSelector(),
1303                                      SelLocs,
1304                                      OldMsg->getMethodDecl(),
1305                                      RHS,
1306                                      OldMsg->getRightLoc(),
1307                                      OldMsg->isImplicit());
1308     break;
1309   }
1310 
1311   Stmt *Replacement = SynthMessageExpr(NewMsg);
1312   ReplaceStmtWithRange(PseudoOp, Replacement, OldRange);
1313   return Replacement;
1314 }
1315 
1316 Stmt *RewriteObjC::RewritePropertyOrImplicitGetter(PseudoObjectExpr *PseudoOp) {
1317   SourceRange OldRange = PseudoOp->getSourceRange();
1318 
1319   // We just magically know some things about the structure of this
1320   // expression.
1321   ObjCMessageExpr *OldMsg =
1322     cast<ObjCMessageExpr>(PseudoOp->getResultExpr()->IgnoreImplicit());
1323 
1324   // Because the rewriter doesn't allow us to rewrite rewritten code,
1325   // we need to suppress rewriting the sub-statements.
1326   Expr *Base = nullptr;
1327   {
1328     DisableReplaceStmtScope S(*this);
1329 
1330     // Rebuild the base expression if we have one.
1331     if (OldMsg->getReceiverKind() == ObjCMessageExpr::Instance) {
1332       Base = OldMsg->getInstanceReceiver();
1333       Base = cast<OpaqueValueExpr>(Base)->getSourceExpr();
1334       Base = cast<Expr>(RewriteFunctionBodyOrGlobalInitializer(Base));
1335     }
1336   }
1337 
1338   // Intentionally empty.
1339   SmallVector<SourceLocation, 1> SelLocs;
1340   SmallVector<Expr*, 1> Args;
1341 
1342   ObjCMessageExpr *NewMsg = nullptr;
1343   switch (OldMsg->getReceiverKind()) {
1344   case ObjCMessageExpr::Class:
1345     NewMsg = ObjCMessageExpr::Create(*Context, OldMsg->getType(),
1346                                      OldMsg->getValueKind(),
1347                                      OldMsg->getLeftLoc(),
1348                                      OldMsg->getClassReceiverTypeInfo(),
1349                                      OldMsg->getSelector(),
1350                                      SelLocs,
1351                                      OldMsg->getMethodDecl(),
1352                                      Args,
1353                                      OldMsg->getRightLoc(),
1354                                      OldMsg->isImplicit());
1355     break;
1356 
1357   case ObjCMessageExpr::Instance:
1358     NewMsg = ObjCMessageExpr::Create(*Context, OldMsg->getType(),
1359                                      OldMsg->getValueKind(),
1360                                      OldMsg->getLeftLoc(),
1361                                      Base,
1362                                      OldMsg->getSelector(),
1363                                      SelLocs,
1364                                      OldMsg->getMethodDecl(),
1365                                      Args,
1366                                      OldMsg->getRightLoc(),
1367                                      OldMsg->isImplicit());
1368     break;
1369 
1370   case ObjCMessageExpr::SuperClass:
1371   case ObjCMessageExpr::SuperInstance:
1372     NewMsg = ObjCMessageExpr::Create(*Context, OldMsg->getType(),
1373                                      OldMsg->getValueKind(),
1374                                      OldMsg->getLeftLoc(),
1375                                      OldMsg->getSuperLoc(),
1376                  OldMsg->getReceiverKind() == ObjCMessageExpr::SuperInstance,
1377                                      OldMsg->getSuperType(),
1378                                      OldMsg->getSelector(),
1379                                      SelLocs,
1380                                      OldMsg->getMethodDecl(),
1381                                      Args,
1382                                      OldMsg->getRightLoc(),
1383                                      OldMsg->isImplicit());
1384     break;
1385   }
1386 
1387   Stmt *Replacement = SynthMessageExpr(NewMsg);
1388   ReplaceStmtWithRange(PseudoOp, Replacement, OldRange);
1389   return Replacement;
1390 }
1391 
1392 /// SynthCountByEnumWithState - To print:
1393 /// ((unsigned int (*)
1394 ///  (id, SEL, struct __objcFastEnumerationState *, id *, unsigned int))
1395 ///  (void *)objc_msgSend)((id)l_collection,
1396 ///                        sel_registerName(
1397 ///                          "countByEnumeratingWithState:objects:count:"),
1398 ///                        &enumState,
1399 ///                        (id *)__rw_items, (unsigned int)16)
1400 ///
1401 void RewriteObjC::SynthCountByEnumWithState(std::string &buf) {
1402   buf += "((unsigned int (*) (id, SEL, struct __objcFastEnumerationState *, "
1403   "id *, unsigned int))(void *)objc_msgSend)";
1404   buf += "\n\t\t";
1405   buf += "((id)l_collection,\n\t\t";
1406   buf += "sel_registerName(\"countByEnumeratingWithState:objects:count:\"),";
1407   buf += "\n\t\t";
1408   buf += "&enumState, "
1409          "(id *)__rw_items, (unsigned int)16)";
1410 }
1411 
1412 /// RewriteBreakStmt - Rewrite for a break-stmt inside an ObjC2's foreach
1413 /// statement to exit to its outer synthesized loop.
1414 ///
1415 Stmt *RewriteObjC::RewriteBreakStmt(BreakStmt *S) {
1416   if (Stmts.empty() || !isa<ObjCForCollectionStmt>(Stmts.back()))
1417     return S;
1418   // replace break with goto __break_label
1419   std::string buf;
1420 
1421   SourceLocation startLoc = S->getBeginLoc();
1422   buf = "goto __break_label_";
1423   buf += utostr(ObjCBcLabelNo.back());
1424   ReplaceText(startLoc, strlen("break"), buf);
1425 
1426   return nullptr;
1427 }
1428 
1429 /// RewriteContinueStmt - Rewrite for a continue-stmt inside an ObjC2's foreach
1430 /// statement to continue with its inner synthesized loop.
1431 ///
1432 Stmt *RewriteObjC::RewriteContinueStmt(ContinueStmt *S) {
1433   if (Stmts.empty() || !isa<ObjCForCollectionStmt>(Stmts.back()))
1434     return S;
1435   // replace continue with goto __continue_label
1436   std::string buf;
1437 
1438   SourceLocation startLoc = S->getBeginLoc();
1439   buf = "goto __continue_label_";
1440   buf += utostr(ObjCBcLabelNo.back());
1441   ReplaceText(startLoc, strlen("continue"), buf);
1442 
1443   return nullptr;
1444 }
1445 
1446 /// RewriteObjCForCollectionStmt - Rewriter for ObjC2's foreach statement.
1447 ///  It rewrites:
1448 /// for ( type elem in collection) { stmts; }
1449 
1450 /// Into:
1451 /// {
1452 ///   type elem;
1453 ///   struct __objcFastEnumerationState enumState = { 0 };
1454 ///   id __rw_items[16];
1455 ///   id l_collection = (id)collection;
1456 ///   unsigned long limit = [l_collection countByEnumeratingWithState:&enumState
1457 ///                                       objects:__rw_items count:16];
1458 /// if (limit) {
1459 ///   unsigned long startMutations = *enumState.mutationsPtr;
1460 ///   do {
1461 ///        unsigned long counter = 0;
1462 ///        do {
1463 ///             if (startMutations != *enumState.mutationsPtr)
1464 ///               objc_enumerationMutation(l_collection);
1465 ///             elem = (type)enumState.itemsPtr[counter++];
1466 ///             stmts;
1467 ///             __continue_label: ;
1468 ///        } while (counter < limit);
1469 ///   } while (limit = [l_collection countByEnumeratingWithState:&enumState
1470 ///                                  objects:__rw_items count:16]);
1471 ///   elem = nil;
1472 ///   __break_label: ;
1473 ///  }
1474 ///  else
1475 ///       elem = nil;
1476 ///  }
1477 ///
1478 Stmt *RewriteObjC::RewriteObjCForCollectionStmt(ObjCForCollectionStmt *S,
1479                                                 SourceLocation OrigEnd) {
1480   assert(!Stmts.empty() && "ObjCForCollectionStmt - Statement stack empty");
1481   assert(isa<ObjCForCollectionStmt>(Stmts.back()) &&
1482          "ObjCForCollectionStmt Statement stack mismatch");
1483   assert(!ObjCBcLabelNo.empty() &&
1484          "ObjCForCollectionStmt - Label No stack empty");
1485 
1486   SourceLocation startLoc = S->getBeginLoc();
1487   const char *startBuf = SM->getCharacterData(startLoc);
1488   StringRef elementName;
1489   std::string elementTypeAsString;
1490   std::string buf;
1491   buf = "\n{\n\t";
1492   if (DeclStmt *DS = dyn_cast<DeclStmt>(S->getElement())) {
1493     // type elem;
1494     NamedDecl* D = cast<NamedDecl>(DS->getSingleDecl());
1495     QualType ElementType = cast<ValueDecl>(D)->getType();
1496     if (ElementType->isObjCQualifiedIdType() ||
1497         ElementType->isObjCQualifiedInterfaceType())
1498       // Simply use 'id' for all qualified types.
1499       elementTypeAsString = "id";
1500     else
1501       elementTypeAsString = ElementType.getAsString(Context->getPrintingPolicy());
1502     buf += elementTypeAsString;
1503     buf += " ";
1504     elementName = D->getName();
1505     buf += elementName;
1506     buf += ";\n\t";
1507   }
1508   else {
1509     DeclRefExpr *DR = cast<DeclRefExpr>(S->getElement());
1510     elementName = DR->getDecl()->getName();
1511     ValueDecl *VD = DR->getDecl();
1512     if (VD->getType()->isObjCQualifiedIdType() ||
1513         VD->getType()->isObjCQualifiedInterfaceType())
1514       // Simply use 'id' for all qualified types.
1515       elementTypeAsString = "id";
1516     else
1517       elementTypeAsString = VD->getType().getAsString(Context->getPrintingPolicy());
1518   }
1519 
1520   // struct __objcFastEnumerationState enumState = { 0 };
1521   buf += "struct __objcFastEnumerationState enumState = { 0 };\n\t";
1522   // id __rw_items[16];
1523   buf += "id __rw_items[16];\n\t";
1524   // id l_collection = (id)
1525   buf += "id l_collection = (id)";
1526   // Find start location of 'collection' the hard way!
1527   const char *startCollectionBuf = startBuf;
1528   startCollectionBuf += 3;  // skip 'for'
1529   startCollectionBuf = strchr(startCollectionBuf, '(');
1530   startCollectionBuf++; // skip '('
1531   // find 'in' and skip it.
1532   while (*startCollectionBuf != ' ' ||
1533          *(startCollectionBuf+1) != 'i' || *(startCollectionBuf+2) != 'n' ||
1534          (*(startCollectionBuf+3) != ' ' &&
1535           *(startCollectionBuf+3) != '[' && *(startCollectionBuf+3) != '('))
1536     startCollectionBuf++;
1537   startCollectionBuf += 3;
1538 
1539   // Replace: "for (type element in" with string constructed thus far.
1540   ReplaceText(startLoc, startCollectionBuf - startBuf, buf);
1541   // Replace ')' in for '(' type elem in collection ')' with ';'
1542   SourceLocation rightParenLoc = S->getRParenLoc();
1543   const char *rparenBuf = SM->getCharacterData(rightParenLoc);
1544   SourceLocation lparenLoc = startLoc.getLocWithOffset(rparenBuf-startBuf);
1545   buf = ";\n\t";
1546 
1547   // unsigned long limit = [l_collection countByEnumeratingWithState:&enumState
1548   //                                   objects:__rw_items count:16];
1549   // which is synthesized into:
1550   // unsigned int limit =
1551   // ((unsigned int (*)
1552   //  (id, SEL, struct __objcFastEnumerationState *, id *, unsigned int))
1553   //  (void *)objc_msgSend)((id)l_collection,
1554   //                        sel_registerName(
1555   //                          "countByEnumeratingWithState:objects:count:"),
1556   //                        (struct __objcFastEnumerationState *)&state,
1557   //                        (id *)__rw_items, (unsigned int)16);
1558   buf += "unsigned long limit =\n\t\t";
1559   SynthCountByEnumWithState(buf);
1560   buf += ";\n\t";
1561   /// if (limit) {
1562   ///   unsigned long startMutations = *enumState.mutationsPtr;
1563   ///   do {
1564   ///        unsigned long counter = 0;
1565   ///        do {
1566   ///             if (startMutations != *enumState.mutationsPtr)
1567   ///               objc_enumerationMutation(l_collection);
1568   ///             elem = (type)enumState.itemsPtr[counter++];
1569   buf += "if (limit) {\n\t";
1570   buf += "unsigned long startMutations = *enumState.mutationsPtr;\n\t";
1571   buf += "do {\n\t\t";
1572   buf += "unsigned long counter = 0;\n\t\t";
1573   buf += "do {\n\t\t\t";
1574   buf += "if (startMutations != *enumState.mutationsPtr)\n\t\t\t\t";
1575   buf += "objc_enumerationMutation(l_collection);\n\t\t\t";
1576   buf += elementName;
1577   buf += " = (";
1578   buf += elementTypeAsString;
1579   buf += ")enumState.itemsPtr[counter++];";
1580   // Replace ')' in for '(' type elem in collection ')' with all of these.
1581   ReplaceText(lparenLoc, 1, buf);
1582 
1583   ///            __continue_label: ;
1584   ///        } while (counter < limit);
1585   ///   } while (limit = [l_collection countByEnumeratingWithState:&enumState
1586   ///                                  objects:__rw_items count:16]);
1587   ///   elem = nil;
1588   ///   __break_label: ;
1589   ///  }
1590   ///  else
1591   ///       elem = nil;
1592   ///  }
1593   ///
1594   buf = ";\n\t";
1595   buf += "__continue_label_";
1596   buf += utostr(ObjCBcLabelNo.back());
1597   buf += ": ;";
1598   buf += "\n\t\t";
1599   buf += "} while (counter < limit);\n\t";
1600   buf += "} while (limit = ";
1601   SynthCountByEnumWithState(buf);
1602   buf += ");\n\t";
1603   buf += elementName;
1604   buf += " = ((";
1605   buf += elementTypeAsString;
1606   buf += ")0);\n\t";
1607   buf += "__break_label_";
1608   buf += utostr(ObjCBcLabelNo.back());
1609   buf += ": ;\n\t";
1610   buf += "}\n\t";
1611   buf += "else\n\t\t";
1612   buf += elementName;
1613   buf += " = ((";
1614   buf += elementTypeAsString;
1615   buf += ")0);\n\t";
1616   buf += "}\n";
1617 
1618   // Insert all these *after* the statement body.
1619   // FIXME: If this should support Obj-C++, support CXXTryStmt
1620   if (isa<CompoundStmt>(S->getBody())) {
1621     SourceLocation endBodyLoc = OrigEnd.getLocWithOffset(1);
1622     InsertText(endBodyLoc, buf);
1623   } else {
1624     /* Need to treat single statements specially. For example:
1625      *
1626      *     for (A *a in b) if (stuff()) break;
1627      *     for (A *a in b) xxxyy;
1628      *
1629      * The following code simply scans ahead to the semi to find the actual end.
1630      */
1631     const char *stmtBuf = SM->getCharacterData(OrigEnd);
1632     const char *semiBuf = strchr(stmtBuf, ';');
1633     assert(semiBuf && "Can't find ';'");
1634     SourceLocation endBodyLoc = OrigEnd.getLocWithOffset(semiBuf-stmtBuf+1);
1635     InsertText(endBodyLoc, buf);
1636   }
1637   Stmts.pop_back();
1638   ObjCBcLabelNo.pop_back();
1639   return nullptr;
1640 }
1641 
1642 /// RewriteObjCSynchronizedStmt -
1643 /// This routine rewrites @synchronized(expr) stmt;
1644 /// into:
1645 /// objc_sync_enter(expr);
1646 /// @try stmt @finally { objc_sync_exit(expr); }
1647 ///
1648 Stmt *RewriteObjC::RewriteObjCSynchronizedStmt(ObjCAtSynchronizedStmt *S) {
1649   // Get the start location and compute the semi location.
1650   SourceLocation startLoc = S->getBeginLoc();
1651   const char *startBuf = SM->getCharacterData(startLoc);
1652 
1653   assert((*startBuf == '@') && "bogus @synchronized location");
1654 
1655   std::string buf;
1656   buf = "objc_sync_enter((id)";
1657   const char *lparenBuf = startBuf;
1658   while (*lparenBuf != '(') lparenBuf++;
1659   ReplaceText(startLoc, lparenBuf-startBuf+1, buf);
1660   // We can't use S->getSynchExpr()->getEndLoc() to find the end location, since
1661   // the sync expression is typically a message expression that's already
1662   // been rewritten! (which implies the SourceLocation's are invalid).
1663   SourceLocation endLoc = S->getSynchBody()->getBeginLoc();
1664   const char *endBuf = SM->getCharacterData(endLoc);
1665   while (*endBuf != ')') endBuf--;
1666   SourceLocation rparenLoc = startLoc.getLocWithOffset(endBuf-startBuf);
1667   buf = ");\n";
1668   // declare a new scope with two variables, _stack and _rethrow.
1669   buf += "/* @try scope begin */ \n{ struct _objc_exception_data {\n";
1670   buf += "int buf[18/*32-bit i386*/];\n";
1671   buf += "char *pointers[4];} _stack;\n";
1672   buf += "id volatile _rethrow = 0;\n";
1673   buf += "objc_exception_try_enter(&_stack);\n";
1674   buf += "if (!_setjmp(_stack.buf)) /* @try block continue */\n";
1675   ReplaceText(rparenLoc, 1, buf);
1676   startLoc = S->getSynchBody()->getEndLoc();
1677   startBuf = SM->getCharacterData(startLoc);
1678 
1679   assert((*startBuf == '}') && "bogus @synchronized block");
1680   SourceLocation lastCurlyLoc = startLoc;
1681   buf = "}\nelse {\n";
1682   buf += "  _rethrow = objc_exception_extract(&_stack);\n";
1683   buf += "}\n";
1684   buf += "{ /* implicit finally clause */\n";
1685   buf += "  if (!_rethrow) objc_exception_try_exit(&_stack);\n";
1686 
1687   std::string syncBuf;
1688   syncBuf += " objc_sync_exit(";
1689 
1690   Expr *syncExpr = S->getSynchExpr();
1691   CastKind CK = syncExpr->getType()->isObjCObjectPointerType()
1692                   ? CK_BitCast :
1693                 syncExpr->getType()->isBlockPointerType()
1694                   ? CK_BlockPointerToObjCPointerCast
1695                   : CK_CPointerToObjCPointerCast;
1696   syncExpr = NoTypeInfoCStyleCastExpr(Context, Context->getObjCIdType(),
1697                                       CK, syncExpr);
1698   std::string syncExprBufS;
1699   llvm::raw_string_ostream syncExprBuf(syncExprBufS);
1700   assert(syncExpr != nullptr && "Expected non-null Expr");
1701   syncExpr->printPretty(syncExprBuf, nullptr, PrintingPolicy(LangOpts));
1702   syncBuf += syncExprBuf.str();
1703   syncBuf += ");";
1704 
1705   buf += syncBuf;
1706   buf += "\n  if (_rethrow) objc_exception_throw(_rethrow);\n";
1707   buf += "}\n";
1708   buf += "}";
1709 
1710   ReplaceText(lastCurlyLoc, 1, buf);
1711 
1712   bool hasReturns = false;
1713   HasReturnStmts(S->getSynchBody(), hasReturns);
1714   if (hasReturns)
1715     RewriteSyncReturnStmts(S->getSynchBody(), syncBuf);
1716 
1717   return nullptr;
1718 }
1719 
1720 void RewriteObjC::WarnAboutReturnGotoStmts(Stmt *S)
1721 {
1722   // Perform a bottom up traversal of all children.
1723   for (Stmt *SubStmt : S->children())
1724     if (SubStmt)
1725       WarnAboutReturnGotoStmts(SubStmt);
1726 
1727   if (isa<ReturnStmt>(S) || isa<GotoStmt>(S)) {
1728     Diags.Report(Context->getFullLoc(S->getBeginLoc()),
1729                  TryFinallyContainsReturnDiag);
1730   }
1731 }
1732 
1733 void RewriteObjC::HasReturnStmts(Stmt *S, bool &hasReturns)
1734 {
1735   // Perform a bottom up traversal of all children.
1736   for (Stmt *SubStmt : S->children())
1737     if (SubStmt)
1738       HasReturnStmts(SubStmt, hasReturns);
1739 
1740   if (isa<ReturnStmt>(S))
1741     hasReturns = true;
1742 }
1743 
1744 void RewriteObjC::RewriteTryReturnStmts(Stmt *S) {
1745   // Perform a bottom up traversal of all children.
1746   for (Stmt *SubStmt : S->children())
1747     if (SubStmt) {
1748       RewriteTryReturnStmts(SubStmt);
1749     }
1750   if (isa<ReturnStmt>(S)) {
1751     SourceLocation startLoc = S->getBeginLoc();
1752     const char *startBuf = SM->getCharacterData(startLoc);
1753     const char *semiBuf = strchr(startBuf, ';');
1754     assert((*semiBuf == ';') && "RewriteTryReturnStmts: can't find ';'");
1755     SourceLocation onePastSemiLoc = startLoc.getLocWithOffset(semiBuf-startBuf+1);
1756 
1757     std::string buf;
1758     buf = "{ objc_exception_try_exit(&_stack); return";
1759 
1760     ReplaceText(startLoc, 6, buf);
1761     InsertText(onePastSemiLoc, "}");
1762   }
1763 }
1764 
1765 void RewriteObjC::RewriteSyncReturnStmts(Stmt *S, std::string syncExitBuf) {
1766   // Perform a bottom up traversal of all children.
1767   for (Stmt *SubStmt : S->children())
1768     if (SubStmt) {
1769       RewriteSyncReturnStmts(SubStmt, syncExitBuf);
1770     }
1771   if (isa<ReturnStmt>(S)) {
1772     SourceLocation startLoc = S->getBeginLoc();
1773     const char *startBuf = SM->getCharacterData(startLoc);
1774 
1775     const char *semiBuf = strchr(startBuf, ';');
1776     assert((*semiBuf == ';') && "RewriteSyncReturnStmts: can't find ';'");
1777     SourceLocation onePastSemiLoc = startLoc.getLocWithOffset(semiBuf-startBuf+1);
1778 
1779     std::string buf;
1780     buf = "{ objc_exception_try_exit(&_stack);";
1781     buf += syncExitBuf;
1782     buf += " return";
1783 
1784     ReplaceText(startLoc, 6, buf);
1785     InsertText(onePastSemiLoc, "}");
1786   }
1787 }
1788 
1789 Stmt *RewriteObjC::RewriteObjCTryStmt(ObjCAtTryStmt *S) {
1790   // Get the start location and compute the semi location.
1791   SourceLocation startLoc = S->getBeginLoc();
1792   const char *startBuf = SM->getCharacterData(startLoc);
1793 
1794   assert((*startBuf == '@') && "bogus @try location");
1795 
1796   std::string buf;
1797   // declare a new scope with two variables, _stack and _rethrow.
1798   buf = "/* @try scope begin */ { struct _objc_exception_data {\n";
1799   buf += "int buf[18/*32-bit i386*/];\n";
1800   buf += "char *pointers[4];} _stack;\n";
1801   buf += "id volatile _rethrow = 0;\n";
1802   buf += "objc_exception_try_enter(&_stack);\n";
1803   buf += "if (!_setjmp(_stack.buf)) /* @try block continue */\n";
1804 
1805   ReplaceText(startLoc, 4, buf);
1806 
1807   startLoc = S->getTryBody()->getEndLoc();
1808   startBuf = SM->getCharacterData(startLoc);
1809 
1810   assert((*startBuf == '}') && "bogus @try block");
1811 
1812   SourceLocation lastCurlyLoc = startLoc;
1813   if (S->getNumCatchStmts()) {
1814     startLoc = startLoc.getLocWithOffset(1);
1815     buf = " /* @catch begin */ else {\n";
1816     buf += " id _caught = objc_exception_extract(&_stack);\n";
1817     buf += " objc_exception_try_enter (&_stack);\n";
1818     buf += " if (_setjmp(_stack.buf))\n";
1819     buf += "   _rethrow = objc_exception_extract(&_stack);\n";
1820     buf += " else { /* @catch continue */";
1821 
1822     InsertText(startLoc, buf);
1823   } else { /* no catch list */
1824     buf = "}\nelse {\n";
1825     buf += "  _rethrow = objc_exception_extract(&_stack);\n";
1826     buf += "}";
1827     ReplaceText(lastCurlyLoc, 1, buf);
1828   }
1829   Stmt *lastCatchBody = nullptr;
1830   for (unsigned I = 0, N = S->getNumCatchStmts(); I != N; ++I) {
1831     ObjCAtCatchStmt *Catch = S->getCatchStmt(I);
1832     VarDecl *catchDecl = Catch->getCatchParamDecl();
1833 
1834     if (I == 0)
1835       buf = "if ("; // we are generating code for the first catch clause
1836     else
1837       buf = "else if (";
1838     startLoc = Catch->getBeginLoc();
1839     startBuf = SM->getCharacterData(startLoc);
1840 
1841     assert((*startBuf == '@') && "bogus @catch location");
1842 
1843     const char *lParenLoc = strchr(startBuf, '(');
1844 
1845     if (Catch->hasEllipsis()) {
1846       // Now rewrite the body...
1847       lastCatchBody = Catch->getCatchBody();
1848       SourceLocation bodyLoc = lastCatchBody->getBeginLoc();
1849       const char *bodyBuf = SM->getCharacterData(bodyLoc);
1850       assert(*SM->getCharacterData(Catch->getRParenLoc()) == ')' &&
1851              "bogus @catch paren location");
1852       assert((*bodyBuf == '{') && "bogus @catch body location");
1853 
1854       buf += "1) { id _tmp = _caught;";
1855       Rewrite.ReplaceText(startLoc, bodyBuf-startBuf+1, buf);
1856     } else if (catchDecl) {
1857       QualType t = catchDecl->getType();
1858       if (t == Context->getObjCIdType()) {
1859         buf += "1) { ";
1860         ReplaceText(startLoc, lParenLoc-startBuf+1, buf);
1861       } else if (const ObjCObjectPointerType *Ptr =
1862                    t->getAs<ObjCObjectPointerType>()) {
1863         // Should be a pointer to a class.
1864         ObjCInterfaceDecl *IDecl = Ptr->getObjectType()->getInterface();
1865         if (IDecl) {
1866           buf += "objc_exception_match((struct objc_class *)objc_getClass(\"";
1867           buf += IDecl->getNameAsString();
1868           buf += "\"), (struct objc_object *)_caught)) { ";
1869           ReplaceText(startLoc, lParenLoc-startBuf+1, buf);
1870         }
1871       }
1872       // Now rewrite the body...
1873       lastCatchBody = Catch->getCatchBody();
1874       SourceLocation rParenLoc = Catch->getRParenLoc();
1875       SourceLocation bodyLoc = lastCatchBody->getBeginLoc();
1876       const char *bodyBuf = SM->getCharacterData(bodyLoc);
1877       const char *rParenBuf = SM->getCharacterData(rParenLoc);
1878       assert((*rParenBuf == ')') && "bogus @catch paren location");
1879       assert((*bodyBuf == '{') && "bogus @catch body location");
1880 
1881       // Here we replace ") {" with "= _caught;" (which initializes and
1882       // declares the @catch parameter).
1883       ReplaceText(rParenLoc, bodyBuf-rParenBuf+1, " = _caught;");
1884     } else {
1885       llvm_unreachable("@catch rewrite bug");
1886     }
1887   }
1888   // Complete the catch list...
1889   if (lastCatchBody) {
1890     SourceLocation bodyLoc = lastCatchBody->getEndLoc();
1891     assert(*SM->getCharacterData(bodyLoc) == '}' &&
1892            "bogus @catch body location");
1893 
1894     // Insert the last (implicit) else clause *before* the right curly brace.
1895     bodyLoc = bodyLoc.getLocWithOffset(-1);
1896     buf = "} /* last catch end */\n";
1897     buf += "else {\n";
1898     buf += " _rethrow = _caught;\n";
1899     buf += " objc_exception_try_exit(&_stack);\n";
1900     buf += "} } /* @catch end */\n";
1901     if (!S->getFinallyStmt())
1902       buf += "}\n";
1903     InsertText(bodyLoc, buf);
1904 
1905     // Set lastCurlyLoc
1906     lastCurlyLoc = lastCatchBody->getEndLoc();
1907   }
1908   if (ObjCAtFinallyStmt *finalStmt = S->getFinallyStmt()) {
1909     startLoc = finalStmt->getBeginLoc();
1910     startBuf = SM->getCharacterData(startLoc);
1911     assert((*startBuf == '@') && "bogus @finally start");
1912 
1913     ReplaceText(startLoc, 8, "/* @finally */");
1914 
1915     Stmt *body = finalStmt->getFinallyBody();
1916     SourceLocation startLoc = body->getBeginLoc();
1917     SourceLocation endLoc = body->getEndLoc();
1918     assert(*SM->getCharacterData(startLoc) == '{' &&
1919            "bogus @finally body location");
1920     assert(*SM->getCharacterData(endLoc) == '}' &&
1921            "bogus @finally body location");
1922 
1923     startLoc = startLoc.getLocWithOffset(1);
1924     InsertText(startLoc, " if (!_rethrow) objc_exception_try_exit(&_stack);\n");
1925     endLoc = endLoc.getLocWithOffset(-1);
1926     InsertText(endLoc, " if (_rethrow) objc_exception_throw(_rethrow);\n");
1927 
1928     // Set lastCurlyLoc
1929     lastCurlyLoc = body->getEndLoc();
1930 
1931     // Now check for any return/continue/go statements within the @try.
1932     WarnAboutReturnGotoStmts(S->getTryBody());
1933   } else { /* no finally clause - make sure we synthesize an implicit one */
1934     buf = "{ /* implicit finally clause */\n";
1935     buf += " if (!_rethrow) objc_exception_try_exit(&_stack);\n";
1936     buf += " if (_rethrow) objc_exception_throw(_rethrow);\n";
1937     buf += "}";
1938     ReplaceText(lastCurlyLoc, 1, buf);
1939 
1940     // Now check for any return/continue/go statements within the @try.
1941     // The implicit finally clause won't called if the @try contains any
1942     // jump statements.
1943     bool hasReturns = false;
1944     HasReturnStmts(S->getTryBody(), hasReturns);
1945     if (hasReturns)
1946       RewriteTryReturnStmts(S->getTryBody());
1947   }
1948   // Now emit the final closing curly brace...
1949   lastCurlyLoc = lastCurlyLoc.getLocWithOffset(1);
1950   InsertText(lastCurlyLoc, " } /* @try scope end */\n");
1951   return nullptr;
1952 }
1953 
1954 // This can't be done with ReplaceStmt(S, ThrowExpr), since
1955 // the throw expression is typically a message expression that's already
1956 // been rewritten! (which implies the SourceLocation's are invalid).
1957 Stmt *RewriteObjC::RewriteObjCThrowStmt(ObjCAtThrowStmt *S) {
1958   // Get the start location and compute the semi location.
1959   SourceLocation startLoc = S->getBeginLoc();
1960   const char *startBuf = SM->getCharacterData(startLoc);
1961 
1962   assert((*startBuf == '@') && "bogus @throw location");
1963 
1964   std::string buf;
1965   /* void objc_exception_throw(id) __attribute__((noreturn)); */
1966   if (S->getThrowExpr())
1967     buf = "objc_exception_throw(";
1968   else // add an implicit argument
1969     buf = "objc_exception_throw(_caught";
1970 
1971   // handle "@  throw" correctly.
1972   const char *wBuf = strchr(startBuf, 'w');
1973   assert((*wBuf == 'w') && "@throw: can't find 'w'");
1974   ReplaceText(startLoc, wBuf-startBuf+1, buf);
1975 
1976   const char *semiBuf = strchr(startBuf, ';');
1977   assert((*semiBuf == ';') && "@throw: can't find ';'");
1978   SourceLocation semiLoc = startLoc.getLocWithOffset(semiBuf-startBuf);
1979   ReplaceText(semiLoc, 1, ");");
1980   return nullptr;
1981 }
1982 
1983 Stmt *RewriteObjC::RewriteAtEncode(ObjCEncodeExpr *Exp) {
1984   // Create a new string expression.
1985   std::string StrEncoding;
1986   Context->getObjCEncodingForType(Exp->getEncodedType(), StrEncoding);
1987   Expr *Replacement = getStringLiteral(StrEncoding);
1988   ReplaceStmt(Exp, Replacement);
1989 
1990   // Replace this subexpr in the parent.
1991   // delete Exp; leak for now, see RewritePropertyOrImplicitSetter() usage for more info.
1992   return Replacement;
1993 }
1994 
1995 Stmt *RewriteObjC::RewriteAtSelector(ObjCSelectorExpr *Exp) {
1996   if (!SelGetUidFunctionDecl)
1997     SynthSelGetUidFunctionDecl();
1998   assert(SelGetUidFunctionDecl && "Can't find sel_registerName() decl");
1999   // Create a call to sel_registerName("selName").
2000   SmallVector<Expr*, 8> SelExprs;
2001   SelExprs.push_back(getStringLiteral(Exp->getSelector().getAsString()));
2002   CallExpr *SelExp = SynthesizeCallToFunctionDecl(SelGetUidFunctionDecl,
2003                                                   SelExprs);
2004   ReplaceStmt(Exp, SelExp);
2005   // delete Exp; leak for now, see RewritePropertyOrImplicitSetter() usage for more info.
2006   return SelExp;
2007 }
2008 
2009 CallExpr *
2010 RewriteObjC::SynthesizeCallToFunctionDecl(FunctionDecl *FD,
2011                                           ArrayRef<Expr *> Args,
2012                                           SourceLocation StartLoc,
2013                                           SourceLocation EndLoc) {
2014   // Get the type, we will need to reference it in a couple spots.
2015   QualType msgSendType = FD->getType();
2016 
2017   // Create a reference to the objc_msgSend() declaration.
2018   DeclRefExpr *DRE = new (Context) DeclRefExpr(*Context, FD, false, msgSendType,
2019                                                VK_LValue, SourceLocation());
2020 
2021   // Now, we cast the reference to a pointer to the objc_msgSend type.
2022   QualType pToFunc = Context->getPointerType(msgSendType);
2023   ImplicitCastExpr *ICE =
2024     ImplicitCastExpr::Create(*Context, pToFunc, CK_FunctionToPointerDecay,
2025                              DRE, nullptr, VK_RValue);
2026 
2027   const auto *FT = msgSendType->castAs<FunctionType>();
2028 
2029   CallExpr *Exp = CallExpr::Create(
2030       *Context, ICE, Args, FT->getCallResultType(*Context), VK_RValue, EndLoc);
2031   return Exp;
2032 }
2033 
2034 static bool scanForProtocolRefs(const char *startBuf, const char *endBuf,
2035                                 const char *&startRef, const char *&endRef) {
2036   while (startBuf < endBuf) {
2037     if (*startBuf == '<')
2038       startRef = startBuf; // mark the start.
2039     if (*startBuf == '>') {
2040       if (startRef && *startRef == '<') {
2041         endRef = startBuf; // mark the end.
2042         return true;
2043       }
2044       return false;
2045     }
2046     startBuf++;
2047   }
2048   return false;
2049 }
2050 
2051 static void scanToNextArgument(const char *&argRef) {
2052   int angle = 0;
2053   while (*argRef != ')' && (*argRef != ',' || angle > 0)) {
2054     if (*argRef == '<')
2055       angle++;
2056     else if (*argRef == '>')
2057       angle--;
2058     argRef++;
2059   }
2060   assert(angle == 0 && "scanToNextArgument - bad protocol type syntax");
2061 }
2062 
2063 bool RewriteObjC::needToScanForQualifiers(QualType T) {
2064   if (T->isObjCQualifiedIdType())
2065     return true;
2066   if (const PointerType *PT = T->getAs<PointerType>()) {
2067     if (PT->getPointeeType()->isObjCQualifiedIdType())
2068       return true;
2069   }
2070   if (T->isObjCObjectPointerType()) {
2071     T = T->getPointeeType();
2072     return T->isObjCQualifiedInterfaceType();
2073   }
2074   if (T->isArrayType()) {
2075     QualType ElemTy = Context->getBaseElementType(T);
2076     return needToScanForQualifiers(ElemTy);
2077   }
2078   return false;
2079 }
2080 
2081 void RewriteObjC::RewriteObjCQualifiedInterfaceTypes(Expr *E) {
2082   QualType Type = E->getType();
2083   if (needToScanForQualifiers(Type)) {
2084     SourceLocation Loc, EndLoc;
2085 
2086     if (const CStyleCastExpr *ECE = dyn_cast<CStyleCastExpr>(E)) {
2087       Loc = ECE->getLParenLoc();
2088       EndLoc = ECE->getRParenLoc();
2089     } else {
2090       Loc = E->getBeginLoc();
2091       EndLoc = E->getEndLoc();
2092     }
2093     // This will defend against trying to rewrite synthesized expressions.
2094     if (Loc.isInvalid() || EndLoc.isInvalid())
2095       return;
2096 
2097     const char *startBuf = SM->getCharacterData(Loc);
2098     const char *endBuf = SM->getCharacterData(EndLoc);
2099     const char *startRef = nullptr, *endRef = nullptr;
2100     if (scanForProtocolRefs(startBuf, endBuf, startRef, endRef)) {
2101       // Get the locations of the startRef, endRef.
2102       SourceLocation LessLoc = Loc.getLocWithOffset(startRef-startBuf);
2103       SourceLocation GreaterLoc = Loc.getLocWithOffset(endRef-startBuf+1);
2104       // Comment out the protocol references.
2105       InsertText(LessLoc, "/*");
2106       InsertText(GreaterLoc, "*/");
2107     }
2108   }
2109 }
2110 
2111 void RewriteObjC::RewriteObjCQualifiedInterfaceTypes(Decl *Dcl) {
2112   SourceLocation Loc;
2113   QualType Type;
2114   const FunctionProtoType *proto = nullptr;
2115   if (VarDecl *VD = dyn_cast<VarDecl>(Dcl)) {
2116     Loc = VD->getLocation();
2117     Type = VD->getType();
2118   }
2119   else if (FunctionDecl *FD = dyn_cast<FunctionDecl>(Dcl)) {
2120     Loc = FD->getLocation();
2121     // Check for ObjC 'id' and class types that have been adorned with protocol
2122     // information (id<p>, C<p>*). The protocol references need to be rewritten!
2123     const FunctionType *funcType = FD->getType()->getAs<FunctionType>();
2124     assert(funcType && "missing function type");
2125     proto = dyn_cast<FunctionProtoType>(funcType);
2126     if (!proto)
2127       return;
2128     Type = proto->getReturnType();
2129   }
2130   else if (FieldDecl *FD = dyn_cast<FieldDecl>(Dcl)) {
2131     Loc = FD->getLocation();
2132     Type = FD->getType();
2133   }
2134   else
2135     return;
2136 
2137   if (needToScanForQualifiers(Type)) {
2138     // Since types are unique, we need to scan the buffer.
2139 
2140     const char *endBuf = SM->getCharacterData(Loc);
2141     const char *startBuf = endBuf;
2142     while (*startBuf != ';' && *startBuf != '<' && startBuf != MainFileStart)
2143       startBuf--; // scan backward (from the decl location) for return type.
2144     const char *startRef = nullptr, *endRef = nullptr;
2145     if (scanForProtocolRefs(startBuf, endBuf, startRef, endRef)) {
2146       // Get the locations of the startRef, endRef.
2147       SourceLocation LessLoc = Loc.getLocWithOffset(startRef-endBuf);
2148       SourceLocation GreaterLoc = Loc.getLocWithOffset(endRef-endBuf+1);
2149       // Comment out the protocol references.
2150       InsertText(LessLoc, "/*");
2151       InsertText(GreaterLoc, "*/");
2152     }
2153   }
2154   if (!proto)
2155       return; // most likely, was a variable
2156   // Now check arguments.
2157   const char *startBuf = SM->getCharacterData(Loc);
2158   const char *startFuncBuf = startBuf;
2159   for (unsigned i = 0; i < proto->getNumParams(); i++) {
2160     if (needToScanForQualifiers(proto->getParamType(i))) {
2161       // Since types are unique, we need to scan the buffer.
2162 
2163       const char *endBuf = startBuf;
2164       // scan forward (from the decl location) for argument types.
2165       scanToNextArgument(endBuf);
2166       const char *startRef = nullptr, *endRef = nullptr;
2167       if (scanForProtocolRefs(startBuf, endBuf, startRef, endRef)) {
2168         // Get the locations of the startRef, endRef.
2169         SourceLocation LessLoc =
2170           Loc.getLocWithOffset(startRef-startFuncBuf);
2171         SourceLocation GreaterLoc =
2172           Loc.getLocWithOffset(endRef-startFuncBuf+1);
2173         // Comment out the protocol references.
2174         InsertText(LessLoc, "/*");
2175         InsertText(GreaterLoc, "*/");
2176       }
2177       startBuf = ++endBuf;
2178     }
2179     else {
2180       // If the function name is derived from a macro expansion, then the
2181       // argument buffer will not follow the name. Need to speak with Chris.
2182       while (*startBuf && *startBuf != ')' && *startBuf != ',')
2183         startBuf++; // scan forward (from the decl location) for argument types.
2184       startBuf++;
2185     }
2186   }
2187 }
2188 
2189 void RewriteObjC::RewriteTypeOfDecl(VarDecl *ND) {
2190   QualType QT = ND->getType();
2191   const Type* TypePtr = QT->getAs<Type>();
2192   if (!isa<TypeOfExprType>(TypePtr))
2193     return;
2194   while (isa<TypeOfExprType>(TypePtr)) {
2195     const TypeOfExprType *TypeOfExprTypePtr = cast<TypeOfExprType>(TypePtr);
2196     QT = TypeOfExprTypePtr->getUnderlyingExpr()->getType();
2197     TypePtr = QT->getAs<Type>();
2198   }
2199   // FIXME. This will not work for multiple declarators; as in:
2200   // __typeof__(a) b,c,d;
2201   std::string TypeAsString(QT.getAsString(Context->getPrintingPolicy()));
2202   SourceLocation DeclLoc = ND->getTypeSpecStartLoc();
2203   const char *startBuf = SM->getCharacterData(DeclLoc);
2204   if (ND->getInit()) {
2205     std::string Name(ND->getNameAsString());
2206     TypeAsString += " " + Name + " = ";
2207     Expr *E = ND->getInit();
2208     SourceLocation startLoc;
2209     if (const CStyleCastExpr *ECE = dyn_cast<CStyleCastExpr>(E))
2210       startLoc = ECE->getLParenLoc();
2211     else
2212       startLoc = E->getBeginLoc();
2213     startLoc = SM->getExpansionLoc(startLoc);
2214     const char *endBuf = SM->getCharacterData(startLoc);
2215     ReplaceText(DeclLoc, endBuf-startBuf-1, TypeAsString);
2216   }
2217   else {
2218     SourceLocation X = ND->getEndLoc();
2219     X = SM->getExpansionLoc(X);
2220     const char *endBuf = SM->getCharacterData(X);
2221     ReplaceText(DeclLoc, endBuf-startBuf-1, TypeAsString);
2222   }
2223 }
2224 
2225 // SynthSelGetUidFunctionDecl - SEL sel_registerName(const char *str);
2226 void RewriteObjC::SynthSelGetUidFunctionDecl() {
2227   IdentifierInfo *SelGetUidIdent = &Context->Idents.get("sel_registerName");
2228   SmallVector<QualType, 16> ArgTys;
2229   ArgTys.push_back(Context->getPointerType(Context->CharTy.withConst()));
2230   QualType getFuncType =
2231     getSimpleFunctionType(Context->getObjCSelType(), ArgTys);
2232   SelGetUidFunctionDecl = FunctionDecl::Create(*Context, TUDecl,
2233                                                SourceLocation(),
2234                                                SourceLocation(),
2235                                                SelGetUidIdent, getFuncType,
2236                                                nullptr, SC_Extern);
2237 }
2238 
2239 void RewriteObjC::RewriteFunctionDecl(FunctionDecl *FD) {
2240   // declared in <objc/objc.h>
2241   if (FD->getIdentifier() &&
2242       FD->getName() == "sel_registerName") {
2243     SelGetUidFunctionDecl = FD;
2244     return;
2245   }
2246   RewriteObjCQualifiedInterfaceTypes(FD);
2247 }
2248 
2249 void RewriteObjC::RewriteBlockPointerType(std::string& Str, QualType Type) {
2250   std::string TypeString(Type.getAsString(Context->getPrintingPolicy()));
2251   const char *argPtr = TypeString.c_str();
2252   if (!strchr(argPtr, '^')) {
2253     Str += TypeString;
2254     return;
2255   }
2256   while (*argPtr) {
2257     Str += (*argPtr == '^' ? '*' : *argPtr);
2258     argPtr++;
2259   }
2260 }
2261 
2262 // FIXME. Consolidate this routine with RewriteBlockPointerType.
2263 void RewriteObjC::RewriteBlockPointerTypeVariable(std::string& Str,
2264                                                   ValueDecl *VD) {
2265   QualType Type = VD->getType();
2266   std::string TypeString(Type.getAsString(Context->getPrintingPolicy()));
2267   const char *argPtr = TypeString.c_str();
2268   int paren = 0;
2269   while (*argPtr) {
2270     switch (*argPtr) {
2271       case '(':
2272         Str += *argPtr;
2273         paren++;
2274         break;
2275       case ')':
2276         Str += *argPtr;
2277         paren--;
2278         break;
2279       case '^':
2280         Str += '*';
2281         if (paren == 1)
2282           Str += VD->getNameAsString();
2283         break;
2284       default:
2285         Str += *argPtr;
2286         break;
2287     }
2288     argPtr++;
2289   }
2290 }
2291 
2292 void RewriteObjC::RewriteBlockLiteralFunctionDecl(FunctionDecl *FD) {
2293   SourceLocation FunLocStart = FD->getTypeSpecStartLoc();
2294   const FunctionType *funcType = FD->getType()->getAs<FunctionType>();
2295   const FunctionProtoType *proto = dyn_cast_or_null<FunctionProtoType>(funcType);
2296   if (!proto)
2297     return;
2298   QualType Type = proto->getReturnType();
2299   std::string FdStr = Type.getAsString(Context->getPrintingPolicy());
2300   FdStr += " ";
2301   FdStr += FD->getName();
2302   FdStr +=  "(";
2303   unsigned numArgs = proto->getNumParams();
2304   for (unsigned i = 0; i < numArgs; i++) {
2305     QualType ArgType = proto->getParamType(i);
2306     RewriteBlockPointerType(FdStr, ArgType);
2307     if (i+1 < numArgs)
2308       FdStr += ", ";
2309   }
2310   FdStr +=  ");\n";
2311   InsertText(FunLocStart, FdStr);
2312   CurFunctionDeclToDeclareForBlock = nullptr;
2313 }
2314 
2315 // SynthSuperConstructorFunctionDecl - id objc_super(id obj, id super);
2316 void RewriteObjC::SynthSuperConstructorFunctionDecl() {
2317   if (SuperConstructorFunctionDecl)
2318     return;
2319   IdentifierInfo *msgSendIdent = &Context->Idents.get("__rw_objc_super");
2320   SmallVector<QualType, 16> ArgTys;
2321   QualType argT = Context->getObjCIdType();
2322   assert(!argT.isNull() && "Can't find 'id' type");
2323   ArgTys.push_back(argT);
2324   ArgTys.push_back(argT);
2325   QualType msgSendType = getSimpleFunctionType(Context->getObjCIdType(),
2326                                                ArgTys);
2327   SuperConstructorFunctionDecl = FunctionDecl::Create(*Context, TUDecl,
2328                                                      SourceLocation(),
2329                                                      SourceLocation(),
2330                                                      msgSendIdent, msgSendType,
2331                                                      nullptr, SC_Extern);
2332 }
2333 
2334 // SynthMsgSendFunctionDecl - id objc_msgSend(id self, SEL op, ...);
2335 void RewriteObjC::SynthMsgSendFunctionDecl() {
2336   IdentifierInfo *msgSendIdent = &Context->Idents.get("objc_msgSend");
2337   SmallVector<QualType, 16> ArgTys;
2338   QualType argT = Context->getObjCIdType();
2339   assert(!argT.isNull() && "Can't find 'id' type");
2340   ArgTys.push_back(argT);
2341   argT = Context->getObjCSelType();
2342   assert(!argT.isNull() && "Can't find 'SEL' type");
2343   ArgTys.push_back(argT);
2344   QualType msgSendType = getSimpleFunctionType(Context->getObjCIdType(),
2345                                                ArgTys, /*variadic=*/true);
2346   MsgSendFunctionDecl = FunctionDecl::Create(*Context, TUDecl,
2347                                              SourceLocation(),
2348                                              SourceLocation(),
2349                                              msgSendIdent, msgSendType,
2350                                              nullptr, SC_Extern);
2351 }
2352 
2353 // SynthMsgSendSuperFunctionDecl - id objc_msgSendSuper(struct objc_super *, SEL op, ...);
2354 void RewriteObjC::SynthMsgSendSuperFunctionDecl() {
2355   IdentifierInfo *msgSendIdent = &Context->Idents.get("objc_msgSendSuper");
2356   SmallVector<QualType, 16> ArgTys;
2357   RecordDecl *RD = RecordDecl::Create(*Context, TTK_Struct, TUDecl,
2358                                       SourceLocation(), SourceLocation(),
2359                                       &Context->Idents.get("objc_super"));
2360   QualType argT = Context->getPointerType(Context->getTagDeclType(RD));
2361   assert(!argT.isNull() && "Can't build 'struct objc_super *' type");
2362   ArgTys.push_back(argT);
2363   argT = Context->getObjCSelType();
2364   assert(!argT.isNull() && "Can't find 'SEL' type");
2365   ArgTys.push_back(argT);
2366   QualType msgSendType = getSimpleFunctionType(Context->getObjCIdType(),
2367                                                ArgTys, /*variadic=*/true);
2368   MsgSendSuperFunctionDecl = FunctionDecl::Create(*Context, TUDecl,
2369                                                   SourceLocation(),
2370                                                   SourceLocation(),
2371                                                   msgSendIdent, msgSendType,
2372                                                   nullptr, SC_Extern);
2373 }
2374 
2375 // SynthMsgSendStretFunctionDecl - id objc_msgSend_stret(id self, SEL op, ...);
2376 void RewriteObjC::SynthMsgSendStretFunctionDecl() {
2377   IdentifierInfo *msgSendIdent = &Context->Idents.get("objc_msgSend_stret");
2378   SmallVector<QualType, 16> ArgTys;
2379   QualType argT = Context->getObjCIdType();
2380   assert(!argT.isNull() && "Can't find 'id' type");
2381   ArgTys.push_back(argT);
2382   argT = Context->getObjCSelType();
2383   assert(!argT.isNull() && "Can't find 'SEL' type");
2384   ArgTys.push_back(argT);
2385   QualType msgSendType = getSimpleFunctionType(Context->getObjCIdType(),
2386                                                ArgTys, /*variadic=*/true);
2387   MsgSendStretFunctionDecl = FunctionDecl::Create(*Context, TUDecl,
2388                                                   SourceLocation(),
2389                                                   SourceLocation(),
2390                                                   msgSendIdent, msgSendType,
2391                                                   nullptr, SC_Extern);
2392 }
2393 
2394 // SynthMsgSendSuperStretFunctionDecl -
2395 // id objc_msgSendSuper_stret(struct objc_super *, SEL op, ...);
2396 void RewriteObjC::SynthMsgSendSuperStretFunctionDecl() {
2397   IdentifierInfo *msgSendIdent =
2398     &Context->Idents.get("objc_msgSendSuper_stret");
2399   SmallVector<QualType, 16> ArgTys;
2400   RecordDecl *RD = RecordDecl::Create(*Context, TTK_Struct, TUDecl,
2401                                       SourceLocation(), SourceLocation(),
2402                                       &Context->Idents.get("objc_super"));
2403   QualType argT = Context->getPointerType(Context->getTagDeclType(RD));
2404   assert(!argT.isNull() && "Can't build 'struct objc_super *' type");
2405   ArgTys.push_back(argT);
2406   argT = Context->getObjCSelType();
2407   assert(!argT.isNull() && "Can't find 'SEL' type");
2408   ArgTys.push_back(argT);
2409   QualType msgSendType = getSimpleFunctionType(Context->getObjCIdType(),
2410                                                ArgTys, /*variadic=*/true);
2411   MsgSendSuperStretFunctionDecl = FunctionDecl::Create(*Context, TUDecl,
2412                                                        SourceLocation(),
2413                                                        SourceLocation(),
2414                                                        msgSendIdent,
2415                                                        msgSendType, nullptr,
2416                                                        SC_Extern);
2417 }
2418 
2419 // SynthMsgSendFpretFunctionDecl - double objc_msgSend_fpret(id self, SEL op, ...);
2420 void RewriteObjC::SynthMsgSendFpretFunctionDecl() {
2421   IdentifierInfo *msgSendIdent = &Context->Idents.get("objc_msgSend_fpret");
2422   SmallVector<QualType, 16> ArgTys;
2423   QualType argT = Context->getObjCIdType();
2424   assert(!argT.isNull() && "Can't find 'id' type");
2425   ArgTys.push_back(argT);
2426   argT = Context->getObjCSelType();
2427   assert(!argT.isNull() && "Can't find 'SEL' type");
2428   ArgTys.push_back(argT);
2429   QualType msgSendType = getSimpleFunctionType(Context->DoubleTy,
2430                                                ArgTys, /*variadic=*/true);
2431   MsgSendFpretFunctionDecl = FunctionDecl::Create(*Context, TUDecl,
2432                                                   SourceLocation(),
2433                                                   SourceLocation(),
2434                                                   msgSendIdent, msgSendType,
2435                                                   nullptr, SC_Extern);
2436 }
2437 
2438 // SynthGetClassFunctionDecl - id objc_getClass(const char *name);
2439 void RewriteObjC::SynthGetClassFunctionDecl() {
2440   IdentifierInfo *getClassIdent = &Context->Idents.get("objc_getClass");
2441   SmallVector<QualType, 16> ArgTys;
2442   ArgTys.push_back(Context->getPointerType(Context->CharTy.withConst()));
2443   QualType getClassType = getSimpleFunctionType(Context->getObjCIdType(),
2444                                                 ArgTys);
2445   GetClassFunctionDecl = FunctionDecl::Create(*Context, TUDecl,
2446                                               SourceLocation(),
2447                                               SourceLocation(),
2448                                               getClassIdent, getClassType,
2449                                               nullptr, SC_Extern);
2450 }
2451 
2452 // SynthGetSuperClassFunctionDecl - Class class_getSuperclass(Class cls);
2453 void RewriteObjC::SynthGetSuperClassFunctionDecl() {
2454   IdentifierInfo *getSuperClassIdent =
2455     &Context->Idents.get("class_getSuperclass");
2456   SmallVector<QualType, 16> ArgTys;
2457   ArgTys.push_back(Context->getObjCClassType());
2458   QualType getClassType = getSimpleFunctionType(Context->getObjCClassType(),
2459                                                 ArgTys);
2460   GetSuperClassFunctionDecl = FunctionDecl::Create(*Context, TUDecl,
2461                                                    SourceLocation(),
2462                                                    SourceLocation(),
2463                                                    getSuperClassIdent,
2464                                                    getClassType, nullptr,
2465                                                    SC_Extern);
2466 }
2467 
2468 // SynthGetMetaClassFunctionDecl - id objc_getMetaClass(const char *name);
2469 void RewriteObjC::SynthGetMetaClassFunctionDecl() {
2470   IdentifierInfo *getClassIdent = &Context->Idents.get("objc_getMetaClass");
2471   SmallVector<QualType, 16> ArgTys;
2472   ArgTys.push_back(Context->getPointerType(Context->CharTy.withConst()));
2473   QualType getClassType = getSimpleFunctionType(Context->getObjCIdType(),
2474                                                 ArgTys);
2475   GetMetaClassFunctionDecl = FunctionDecl::Create(*Context, TUDecl,
2476                                                   SourceLocation(),
2477                                                   SourceLocation(),
2478                                                   getClassIdent, getClassType,
2479                                                   nullptr, SC_Extern);
2480 }
2481 
2482 Stmt *RewriteObjC::RewriteObjCStringLiteral(ObjCStringLiteral *Exp) {
2483   assert(Exp != nullptr && "Expected non-null ObjCStringLiteral");
2484   QualType strType = getConstantStringStructType();
2485 
2486   std::string S = "__NSConstantStringImpl_";
2487 
2488   std::string tmpName = InFileName;
2489   unsigned i;
2490   for (i=0; i < tmpName.length(); i++) {
2491     char c = tmpName.at(i);
2492     // replace any non-alphanumeric characters with '_'.
2493     if (!isAlphanumeric(c))
2494       tmpName[i] = '_';
2495   }
2496   S += tmpName;
2497   S += "_";
2498   S += utostr(NumObjCStringLiterals++);
2499 
2500   Preamble += "static __NSConstantStringImpl " + S;
2501   Preamble += " __attribute__ ((section (\"__DATA, __cfstring\"))) = {__CFConstantStringClassReference,";
2502   Preamble += "0x000007c8,"; // utf8_str
2503   // The pretty printer for StringLiteral handles escape characters properly.
2504   std::string prettyBufS;
2505   llvm::raw_string_ostream prettyBuf(prettyBufS);
2506   Exp->getString()->printPretty(prettyBuf, nullptr, PrintingPolicy(LangOpts));
2507   Preamble += prettyBuf.str();
2508   Preamble += ",";
2509   Preamble += utostr(Exp->getString()->getByteLength()) + "};\n";
2510 
2511   VarDecl *NewVD = VarDecl::Create(*Context, TUDecl, SourceLocation(),
2512                                    SourceLocation(), &Context->Idents.get(S),
2513                                    strType, nullptr, SC_Static);
2514   DeclRefExpr *DRE = new (Context)
2515       DeclRefExpr(*Context, NewVD, false, strType, VK_LValue, SourceLocation());
2516   Expr *Unop = new (Context)
2517       UnaryOperator(DRE, UO_AddrOf, Context->getPointerType(DRE->getType()),
2518                     VK_RValue, OK_Ordinary, SourceLocation(), false);
2519   // cast to NSConstantString *
2520   CastExpr *cast = NoTypeInfoCStyleCastExpr(Context, Exp->getType(),
2521                                             CK_CPointerToObjCPointerCast, Unop);
2522   ReplaceStmt(Exp, cast);
2523   // delete Exp; leak for now, see RewritePropertyOrImplicitSetter() usage for more info.
2524   return cast;
2525 }
2526 
2527 // struct objc_super { struct objc_object *receiver; struct objc_class *super; };
2528 QualType RewriteObjC::getSuperStructType() {
2529   if (!SuperStructDecl) {
2530     SuperStructDecl = RecordDecl::Create(*Context, TTK_Struct, TUDecl,
2531                                          SourceLocation(), SourceLocation(),
2532                                          &Context->Idents.get("objc_super"));
2533     QualType FieldTypes[2];
2534 
2535     // struct objc_object *receiver;
2536     FieldTypes[0] = Context->getObjCIdType();
2537     // struct objc_class *super;
2538     FieldTypes[1] = Context->getObjCClassType();
2539 
2540     // Create fields
2541     for (unsigned i = 0; i < 2; ++i) {
2542       SuperStructDecl->addDecl(FieldDecl::Create(*Context, SuperStructDecl,
2543                                                  SourceLocation(),
2544                                                  SourceLocation(), nullptr,
2545                                                  FieldTypes[i], nullptr,
2546                                                  /*BitWidth=*/nullptr,
2547                                                  /*Mutable=*/false,
2548                                                  ICIS_NoInit));
2549     }
2550 
2551     SuperStructDecl->completeDefinition();
2552   }
2553   return Context->getTagDeclType(SuperStructDecl);
2554 }
2555 
2556 QualType RewriteObjC::getConstantStringStructType() {
2557   if (!ConstantStringDecl) {
2558     ConstantStringDecl = RecordDecl::Create(*Context, TTK_Struct, TUDecl,
2559                                             SourceLocation(), SourceLocation(),
2560                          &Context->Idents.get("__NSConstantStringImpl"));
2561     QualType FieldTypes[4];
2562 
2563     // struct objc_object *receiver;
2564     FieldTypes[0] = Context->getObjCIdType();
2565     // int flags;
2566     FieldTypes[1] = Context->IntTy;
2567     // char *str;
2568     FieldTypes[2] = Context->getPointerType(Context->CharTy);
2569     // long length;
2570     FieldTypes[3] = Context->LongTy;
2571 
2572     // Create fields
2573     for (unsigned i = 0; i < 4; ++i) {
2574       ConstantStringDecl->addDecl(FieldDecl::Create(*Context,
2575                                                     ConstantStringDecl,
2576                                                     SourceLocation(),
2577                                                     SourceLocation(), nullptr,
2578                                                     FieldTypes[i], nullptr,
2579                                                     /*BitWidth=*/nullptr,
2580                                                     /*Mutable=*/true,
2581                                                     ICIS_NoInit));
2582     }
2583 
2584     ConstantStringDecl->completeDefinition();
2585   }
2586   return Context->getTagDeclType(ConstantStringDecl);
2587 }
2588 
2589 CallExpr *RewriteObjC::SynthMsgSendStretCallExpr(FunctionDecl *MsgSendStretFlavor,
2590                                                 QualType msgSendType,
2591                                                 QualType returnType,
2592                                                 SmallVectorImpl<QualType> &ArgTypes,
2593                                                 SmallVectorImpl<Expr*> &MsgExprs,
2594                                                 ObjCMethodDecl *Method) {
2595   // Create a reference to the objc_msgSend_stret() declaration.
2596   DeclRefExpr *STDRE =
2597       new (Context) DeclRefExpr(*Context, MsgSendStretFlavor, false,
2598                                 msgSendType, VK_LValue, SourceLocation());
2599   // Need to cast objc_msgSend_stret to "void *" (see above comment).
2600   CastExpr *cast = NoTypeInfoCStyleCastExpr(Context,
2601                                   Context->getPointerType(Context->VoidTy),
2602                                   CK_BitCast, STDRE);
2603   // Now do the "normal" pointer to function cast.
2604   QualType castType = getSimpleFunctionType(returnType, ArgTypes,
2605                                             Method ? Method->isVariadic()
2606                                                    : false);
2607   castType = Context->getPointerType(castType);
2608   cast = NoTypeInfoCStyleCastExpr(Context, castType, CK_BitCast,
2609                                             cast);
2610 
2611   // Don't forget the parens to enforce the proper binding.
2612   ParenExpr *PE = new (Context) ParenExpr(SourceLocation(), SourceLocation(), cast);
2613 
2614   const auto *FT = msgSendType->castAs<FunctionType>();
2615   CallExpr *STCE = CallExpr::Create(*Context, PE, MsgExprs, FT->getReturnType(),
2616                                     VK_RValue, SourceLocation());
2617   return STCE;
2618 }
2619 
2620 Stmt *RewriteObjC::SynthMessageExpr(ObjCMessageExpr *Exp,
2621                                     SourceLocation StartLoc,
2622                                     SourceLocation EndLoc) {
2623   if (!SelGetUidFunctionDecl)
2624     SynthSelGetUidFunctionDecl();
2625   if (!MsgSendFunctionDecl)
2626     SynthMsgSendFunctionDecl();
2627   if (!MsgSendSuperFunctionDecl)
2628     SynthMsgSendSuperFunctionDecl();
2629   if (!MsgSendStretFunctionDecl)
2630     SynthMsgSendStretFunctionDecl();
2631   if (!MsgSendSuperStretFunctionDecl)
2632     SynthMsgSendSuperStretFunctionDecl();
2633   if (!MsgSendFpretFunctionDecl)
2634     SynthMsgSendFpretFunctionDecl();
2635   if (!GetClassFunctionDecl)
2636     SynthGetClassFunctionDecl();
2637   if (!GetSuperClassFunctionDecl)
2638     SynthGetSuperClassFunctionDecl();
2639   if (!GetMetaClassFunctionDecl)
2640     SynthGetMetaClassFunctionDecl();
2641 
2642   // default to objc_msgSend().
2643   FunctionDecl *MsgSendFlavor = MsgSendFunctionDecl;
2644   // May need to use objc_msgSend_stret() as well.
2645   FunctionDecl *MsgSendStretFlavor = nullptr;
2646   if (ObjCMethodDecl *mDecl = Exp->getMethodDecl()) {
2647     QualType resultType = mDecl->getReturnType();
2648     if (resultType->isRecordType())
2649       MsgSendStretFlavor = MsgSendStretFunctionDecl;
2650     else if (resultType->isRealFloatingType())
2651       MsgSendFlavor = MsgSendFpretFunctionDecl;
2652   }
2653 
2654   // Synthesize a call to objc_msgSend().
2655   SmallVector<Expr*, 8> MsgExprs;
2656   switch (Exp->getReceiverKind()) {
2657   case ObjCMessageExpr::SuperClass: {
2658     MsgSendFlavor = MsgSendSuperFunctionDecl;
2659     if (MsgSendStretFlavor)
2660       MsgSendStretFlavor = MsgSendSuperStretFunctionDecl;
2661     assert(MsgSendFlavor && "MsgSendFlavor is NULL!");
2662 
2663     ObjCInterfaceDecl *ClassDecl = CurMethodDef->getClassInterface();
2664 
2665     SmallVector<Expr*, 4> InitExprs;
2666 
2667     // set the receiver to self, the first argument to all methods.
2668     InitExprs.push_back(
2669       NoTypeInfoCStyleCastExpr(Context, Context->getObjCIdType(),
2670                                CK_BitCast,
2671                    new (Context) DeclRefExpr(*Context,
2672                                              CurMethodDef->getSelfDecl(),
2673                                              false,
2674                                              Context->getObjCIdType(),
2675                                              VK_RValue,
2676                                              SourceLocation()))
2677                         ); // set the 'receiver'.
2678 
2679     // (id)class_getSuperclass((Class)objc_getClass("CurrentClass"))
2680     SmallVector<Expr*, 8> ClsExprs;
2681     ClsExprs.push_back(getStringLiteral(ClassDecl->getIdentifier()->getName()));
2682     CallExpr *Cls = SynthesizeCallToFunctionDecl(GetMetaClassFunctionDecl,
2683                                                  ClsExprs, StartLoc, EndLoc);
2684     // (Class)objc_getClass("CurrentClass")
2685     CastExpr *ArgExpr = NoTypeInfoCStyleCastExpr(Context,
2686                                              Context->getObjCClassType(),
2687                                              CK_BitCast, Cls);
2688     ClsExprs.clear();
2689     ClsExprs.push_back(ArgExpr);
2690     Cls = SynthesizeCallToFunctionDecl(GetSuperClassFunctionDecl, ClsExprs,
2691                                        StartLoc, EndLoc);
2692     // (id)class_getSuperclass((Class)objc_getClass("CurrentClass"))
2693     // To turn off a warning, type-cast to 'id'
2694     InitExprs.push_back( // set 'super class', using class_getSuperclass().
2695                         NoTypeInfoCStyleCastExpr(Context,
2696                                                  Context->getObjCIdType(),
2697                                                  CK_BitCast, Cls));
2698     // struct objc_super
2699     QualType superType = getSuperStructType();
2700     Expr *SuperRep;
2701 
2702     if (LangOpts.MicrosoftExt) {
2703       SynthSuperConstructorFunctionDecl();
2704       // Simulate a constructor call...
2705       DeclRefExpr *DRE = new (Context)
2706           DeclRefExpr(*Context, SuperConstructorFunctionDecl, false, superType,
2707                       VK_LValue, SourceLocation());
2708       SuperRep = CallExpr::Create(*Context, DRE, InitExprs, superType,
2709                                   VK_LValue, SourceLocation());
2710       // The code for super is a little tricky to prevent collision with
2711       // the structure definition in the header. The rewriter has it's own
2712       // internal definition (__rw_objc_super) that is uses. This is why
2713       // we need the cast below. For example:
2714       // (struct objc_super *)&__rw_objc_super((id)self, (id)objc_getClass("SUPER"))
2715       //
2716       SuperRep = new (Context) UnaryOperator(SuperRep, UO_AddrOf,
2717                                Context->getPointerType(SuperRep->getType()),
2718                                              VK_RValue, OK_Ordinary,
2719                                              SourceLocation(), false);
2720       SuperRep = NoTypeInfoCStyleCastExpr(Context,
2721                                           Context->getPointerType(superType),
2722                                           CK_BitCast, SuperRep);
2723     } else {
2724       // (struct objc_super) { <exprs from above> }
2725       InitListExpr *ILE =
2726         new (Context) InitListExpr(*Context, SourceLocation(), InitExprs,
2727                                    SourceLocation());
2728       TypeSourceInfo *superTInfo
2729         = Context->getTrivialTypeSourceInfo(superType);
2730       SuperRep = new (Context) CompoundLiteralExpr(SourceLocation(), superTInfo,
2731                                                    superType, VK_LValue,
2732                                                    ILE, false);
2733       // struct objc_super *
2734       SuperRep = new (Context) UnaryOperator(SuperRep, UO_AddrOf,
2735                                Context->getPointerType(SuperRep->getType()),
2736                                              VK_RValue, OK_Ordinary,
2737                                              SourceLocation(), false);
2738     }
2739     MsgExprs.push_back(SuperRep);
2740     break;
2741   }
2742 
2743   case ObjCMessageExpr::Class: {
2744     SmallVector<Expr*, 8> ClsExprs;
2745     auto *Class =
2746         Exp->getClassReceiver()->castAs<ObjCObjectType>()->getInterface();
2747     IdentifierInfo *clsName = Class->getIdentifier();
2748     ClsExprs.push_back(getStringLiteral(clsName->getName()));
2749     CallExpr *Cls = SynthesizeCallToFunctionDecl(GetClassFunctionDecl, ClsExprs,
2750                                                  StartLoc, EndLoc);
2751     MsgExprs.push_back(Cls);
2752     break;
2753   }
2754 
2755   case ObjCMessageExpr::SuperInstance:{
2756     MsgSendFlavor = MsgSendSuperFunctionDecl;
2757     if (MsgSendStretFlavor)
2758       MsgSendStretFlavor = MsgSendSuperStretFunctionDecl;
2759     assert(MsgSendFlavor && "MsgSendFlavor is NULL!");
2760     ObjCInterfaceDecl *ClassDecl = CurMethodDef->getClassInterface();
2761     SmallVector<Expr*, 4> InitExprs;
2762 
2763     InitExprs.push_back(
2764       NoTypeInfoCStyleCastExpr(Context, Context->getObjCIdType(),
2765                                CK_BitCast,
2766                    new (Context) DeclRefExpr(*Context,
2767                                              CurMethodDef->getSelfDecl(),
2768                                              false,
2769                                              Context->getObjCIdType(),
2770                                              VK_RValue, SourceLocation()))
2771                         ); // set the 'receiver'.
2772 
2773     // (id)class_getSuperclass((Class)objc_getClass("CurrentClass"))
2774     SmallVector<Expr*, 8> ClsExprs;
2775     ClsExprs.push_back(getStringLiteral(ClassDecl->getIdentifier()->getName()));
2776     CallExpr *Cls = SynthesizeCallToFunctionDecl(GetClassFunctionDecl, ClsExprs,
2777                                                  StartLoc, EndLoc);
2778     // (Class)objc_getClass("CurrentClass")
2779     CastExpr *ArgExpr = NoTypeInfoCStyleCastExpr(Context,
2780                                                  Context->getObjCClassType(),
2781                                                  CK_BitCast, Cls);
2782     ClsExprs.clear();
2783     ClsExprs.push_back(ArgExpr);
2784     Cls = SynthesizeCallToFunctionDecl(GetSuperClassFunctionDecl, ClsExprs,
2785                                        StartLoc, EndLoc);
2786 
2787     // (id)class_getSuperclass((Class)objc_getClass("CurrentClass"))
2788     // To turn off a warning, type-cast to 'id'
2789     InitExprs.push_back(
2790       // set 'super class', using class_getSuperclass().
2791       NoTypeInfoCStyleCastExpr(Context, Context->getObjCIdType(),
2792                                CK_BitCast, Cls));
2793     // struct objc_super
2794     QualType superType = getSuperStructType();
2795     Expr *SuperRep;
2796 
2797     if (LangOpts.MicrosoftExt) {
2798       SynthSuperConstructorFunctionDecl();
2799       // Simulate a constructor call...
2800       DeclRefExpr *DRE = new (Context)
2801           DeclRefExpr(*Context, SuperConstructorFunctionDecl, false, superType,
2802                       VK_LValue, SourceLocation());
2803       SuperRep = CallExpr::Create(*Context, DRE, InitExprs, superType,
2804                                   VK_LValue, SourceLocation());
2805       // The code for super is a little tricky to prevent collision with
2806       // the structure definition in the header. The rewriter has it's own
2807       // internal definition (__rw_objc_super) that is uses. This is why
2808       // we need the cast below. For example:
2809       // (struct objc_super *)&__rw_objc_super((id)self, (id)objc_getClass("SUPER"))
2810       //
2811       SuperRep = new (Context) UnaryOperator(SuperRep, UO_AddrOf,
2812                                Context->getPointerType(SuperRep->getType()),
2813                                VK_RValue, OK_Ordinary,
2814                                SourceLocation(), false);
2815       SuperRep = NoTypeInfoCStyleCastExpr(Context,
2816                                Context->getPointerType(superType),
2817                                CK_BitCast, SuperRep);
2818     } else {
2819       // (struct objc_super) { <exprs from above> }
2820       InitListExpr *ILE =
2821         new (Context) InitListExpr(*Context, SourceLocation(), InitExprs,
2822                                    SourceLocation());
2823       TypeSourceInfo *superTInfo
2824         = Context->getTrivialTypeSourceInfo(superType);
2825       SuperRep = new (Context) CompoundLiteralExpr(SourceLocation(), superTInfo,
2826                                                    superType, VK_RValue, ILE,
2827                                                    false);
2828     }
2829     MsgExprs.push_back(SuperRep);
2830     break;
2831   }
2832 
2833   case ObjCMessageExpr::Instance: {
2834     // Remove all type-casts because it may contain objc-style types; e.g.
2835     // Foo<Proto> *.
2836     Expr *recExpr = Exp->getInstanceReceiver();
2837     while (CStyleCastExpr *CE = dyn_cast<CStyleCastExpr>(recExpr))
2838       recExpr = CE->getSubExpr();
2839     CastKind CK = recExpr->getType()->isObjCObjectPointerType()
2840                     ? CK_BitCast : recExpr->getType()->isBlockPointerType()
2841                                      ? CK_BlockPointerToObjCPointerCast
2842                                      : CK_CPointerToObjCPointerCast;
2843 
2844     recExpr = NoTypeInfoCStyleCastExpr(Context, Context->getObjCIdType(),
2845                                        CK, recExpr);
2846     MsgExprs.push_back(recExpr);
2847     break;
2848   }
2849   }
2850 
2851   // Create a call to sel_registerName("selName"), it will be the 2nd argument.
2852   SmallVector<Expr*, 8> SelExprs;
2853   SelExprs.push_back(getStringLiteral(Exp->getSelector().getAsString()));
2854   CallExpr *SelExp = SynthesizeCallToFunctionDecl(SelGetUidFunctionDecl,
2855                                                   SelExprs, StartLoc, EndLoc);
2856   MsgExprs.push_back(SelExp);
2857 
2858   // Now push any user supplied arguments.
2859   for (unsigned i = 0; i < Exp->getNumArgs(); i++) {
2860     Expr *userExpr = Exp->getArg(i);
2861     // Make all implicit casts explicit...ICE comes in handy:-)
2862     if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(userExpr)) {
2863       // Reuse the ICE type, it is exactly what the doctor ordered.
2864       QualType type = ICE->getType();
2865       if (needToScanForQualifiers(type))
2866         type = Context->getObjCIdType();
2867       // Make sure we convert "type (^)(...)" to "type (*)(...)".
2868       (void)convertBlockPointerToFunctionPointer(type);
2869       const Expr *SubExpr = ICE->IgnoreParenImpCasts();
2870       CastKind CK;
2871       if (SubExpr->getType()->isIntegralType(*Context) &&
2872           type->isBooleanType()) {
2873         CK = CK_IntegralToBoolean;
2874       } else if (type->isObjCObjectPointerType()) {
2875         if (SubExpr->getType()->isBlockPointerType()) {
2876           CK = CK_BlockPointerToObjCPointerCast;
2877         } else if (SubExpr->getType()->isPointerType()) {
2878           CK = CK_CPointerToObjCPointerCast;
2879         } else {
2880           CK = CK_BitCast;
2881         }
2882       } else {
2883         CK = CK_BitCast;
2884       }
2885 
2886       userExpr = NoTypeInfoCStyleCastExpr(Context, type, CK, userExpr);
2887     }
2888     // Make id<P...> cast into an 'id' cast.
2889     else if (CStyleCastExpr *CE = dyn_cast<CStyleCastExpr>(userExpr)) {
2890       if (CE->getType()->isObjCQualifiedIdType()) {
2891         while ((CE = dyn_cast<CStyleCastExpr>(userExpr)))
2892           userExpr = CE->getSubExpr();
2893         CastKind CK;
2894         if (userExpr->getType()->isIntegralType(*Context)) {
2895           CK = CK_IntegralToPointer;
2896         } else if (userExpr->getType()->isBlockPointerType()) {
2897           CK = CK_BlockPointerToObjCPointerCast;
2898         } else if (userExpr->getType()->isPointerType()) {
2899           CK = CK_CPointerToObjCPointerCast;
2900         } else {
2901           CK = CK_BitCast;
2902         }
2903         userExpr = NoTypeInfoCStyleCastExpr(Context, Context->getObjCIdType(),
2904                                             CK, userExpr);
2905       }
2906     }
2907     MsgExprs.push_back(userExpr);
2908     // We've transferred the ownership to MsgExprs. For now, we *don't* null
2909     // out the argument in the original expression (since we aren't deleting
2910     // the ObjCMessageExpr). See RewritePropertyOrImplicitSetter() usage for more info.
2911     //Exp->setArg(i, 0);
2912   }
2913   // Generate the funky cast.
2914   CastExpr *cast;
2915   SmallVector<QualType, 8> ArgTypes;
2916   QualType returnType;
2917 
2918   // Push 'id' and 'SEL', the 2 implicit arguments.
2919   if (MsgSendFlavor == MsgSendSuperFunctionDecl)
2920     ArgTypes.push_back(Context->getPointerType(getSuperStructType()));
2921   else
2922     ArgTypes.push_back(Context->getObjCIdType());
2923   ArgTypes.push_back(Context->getObjCSelType());
2924   if (ObjCMethodDecl *OMD = Exp->getMethodDecl()) {
2925     // Push any user argument types.
2926     for (const auto *PI : OMD->parameters()) {
2927       QualType t = PI->getType()->isObjCQualifiedIdType()
2928                      ? Context->getObjCIdType()
2929                      : PI->getType();
2930       // Make sure we convert "t (^)(...)" to "t (*)(...)".
2931       (void)convertBlockPointerToFunctionPointer(t);
2932       ArgTypes.push_back(t);
2933     }
2934     returnType = Exp->getType();
2935     convertToUnqualifiedObjCType(returnType);
2936     (void)convertBlockPointerToFunctionPointer(returnType);
2937   } else {
2938     returnType = Context->getObjCIdType();
2939   }
2940   // Get the type, we will need to reference it in a couple spots.
2941   QualType msgSendType = MsgSendFlavor->getType();
2942 
2943   // Create a reference to the objc_msgSend() declaration.
2944   DeclRefExpr *DRE = new (Context) DeclRefExpr(
2945       *Context, MsgSendFlavor, false, msgSendType, VK_LValue, SourceLocation());
2946 
2947   // Need to cast objc_msgSend to "void *" (to workaround a GCC bandaid).
2948   // If we don't do this cast, we get the following bizarre warning/note:
2949   // xx.m:13: warning: function called through a non-compatible type
2950   // xx.m:13: note: if this code is reached, the program will abort
2951   cast = NoTypeInfoCStyleCastExpr(Context,
2952                                   Context->getPointerType(Context->VoidTy),
2953                                   CK_BitCast, DRE);
2954 
2955   // Now do the "normal" pointer to function cast.
2956   // If we don't have a method decl, force a variadic cast.
2957   const ObjCMethodDecl *MD = Exp->getMethodDecl();
2958   QualType castType =
2959     getSimpleFunctionType(returnType, ArgTypes, MD ? MD->isVariadic() : true);
2960   castType = Context->getPointerType(castType);
2961   cast = NoTypeInfoCStyleCastExpr(Context, castType, CK_BitCast,
2962                                   cast);
2963 
2964   // Don't forget the parens to enforce the proper binding.
2965   ParenExpr *PE = new (Context) ParenExpr(StartLoc, EndLoc, cast);
2966 
2967   const auto *FT = msgSendType->castAs<FunctionType>();
2968   CallExpr *CE = CallExpr::Create(*Context, PE, MsgExprs, FT->getReturnType(),
2969                                   VK_RValue, EndLoc);
2970   Stmt *ReplacingStmt = CE;
2971   if (MsgSendStretFlavor) {
2972     // We have the method which returns a struct/union. Must also generate
2973     // call to objc_msgSend_stret and hang both varieties on a conditional
2974     // expression which dictate which one to envoke depending on size of
2975     // method's return type.
2976 
2977     CallExpr *STCE = SynthMsgSendStretCallExpr(MsgSendStretFlavor,
2978                                                msgSendType, returnType,
2979                                                ArgTypes, MsgExprs,
2980                                                Exp->getMethodDecl());
2981 
2982     // Build sizeof(returnType)
2983     UnaryExprOrTypeTraitExpr *sizeofExpr =
2984        new (Context) UnaryExprOrTypeTraitExpr(UETT_SizeOf,
2985                                  Context->getTrivialTypeSourceInfo(returnType),
2986                                  Context->getSizeType(), SourceLocation(),
2987                                  SourceLocation());
2988     // (sizeof(returnType) <= 8 ? objc_msgSend(...) : objc_msgSend_stret(...))
2989     // FIXME: Value of 8 is base on ppc32/x86 ABI for the most common cases.
2990     // For X86 it is more complicated and some kind of target specific routine
2991     // is needed to decide what to do.
2992     unsigned IntSize =
2993       static_cast<unsigned>(Context->getTypeSize(Context->IntTy));
2994     IntegerLiteral *limit = IntegerLiteral::Create(*Context,
2995                                                    llvm::APInt(IntSize, 8),
2996                                                    Context->IntTy,
2997                                                    SourceLocation());
2998     BinaryOperator *lessThanExpr =
2999       new (Context) BinaryOperator(sizeofExpr, limit, BO_LE, Context->IntTy,
3000                                    VK_RValue, OK_Ordinary, SourceLocation(),
3001                                    FPOptions());
3002     // (sizeof(returnType) <= 8 ? objc_msgSend(...) : objc_msgSend_stret(...))
3003     ConditionalOperator *CondExpr =
3004       new (Context) ConditionalOperator(lessThanExpr,
3005                                         SourceLocation(), CE,
3006                                         SourceLocation(), STCE,
3007                                         returnType, VK_RValue, OK_Ordinary);
3008     ReplacingStmt = new (Context) ParenExpr(SourceLocation(), SourceLocation(),
3009                                             CondExpr);
3010   }
3011   // delete Exp; leak for now, see RewritePropertyOrImplicitSetter() usage for more info.
3012   return ReplacingStmt;
3013 }
3014 
3015 Stmt *RewriteObjC::RewriteMessageExpr(ObjCMessageExpr *Exp) {
3016   Stmt *ReplacingStmt =
3017       SynthMessageExpr(Exp, Exp->getBeginLoc(), Exp->getEndLoc());
3018 
3019   // Now do the actual rewrite.
3020   ReplaceStmt(Exp, ReplacingStmt);
3021 
3022   // delete Exp; leak for now, see RewritePropertyOrImplicitSetter() usage for more info.
3023   return ReplacingStmt;
3024 }
3025 
3026 // typedef struct objc_object Protocol;
3027 QualType RewriteObjC::getProtocolType() {
3028   if (!ProtocolTypeDecl) {
3029     TypeSourceInfo *TInfo
3030       = Context->getTrivialTypeSourceInfo(Context->getObjCIdType());
3031     ProtocolTypeDecl = TypedefDecl::Create(*Context, TUDecl,
3032                                            SourceLocation(), SourceLocation(),
3033                                            &Context->Idents.get("Protocol"),
3034                                            TInfo);
3035   }
3036   return Context->getTypeDeclType(ProtocolTypeDecl);
3037 }
3038 
3039 /// RewriteObjCProtocolExpr - Rewrite a protocol expression into
3040 /// a synthesized/forward data reference (to the protocol's metadata).
3041 /// The forward references (and metadata) are generated in
3042 /// RewriteObjC::HandleTranslationUnit().
3043 Stmt *RewriteObjC::RewriteObjCProtocolExpr(ObjCProtocolExpr *Exp) {
3044   std::string Name = "_OBJC_PROTOCOL_" + Exp->getProtocol()->getNameAsString();
3045   IdentifierInfo *ID = &Context->Idents.get(Name);
3046   VarDecl *VD = VarDecl::Create(*Context, TUDecl, SourceLocation(),
3047                                 SourceLocation(), ID, getProtocolType(),
3048                                 nullptr, SC_Extern);
3049   DeclRefExpr *DRE = new (Context) DeclRefExpr(
3050       *Context, VD, false, getProtocolType(), VK_LValue, SourceLocation());
3051   Expr *DerefExpr = new (Context) UnaryOperator(DRE, UO_AddrOf,
3052                              Context->getPointerType(DRE->getType()),
3053                              VK_RValue, OK_Ordinary, SourceLocation(), false);
3054   CastExpr *castExpr = NoTypeInfoCStyleCastExpr(Context, DerefExpr->getType(),
3055                                                 CK_BitCast,
3056                                                 DerefExpr);
3057   ReplaceStmt(Exp, castExpr);
3058   ProtocolExprDecls.insert(Exp->getProtocol()->getCanonicalDecl());
3059   // delete Exp; leak for now, see RewritePropertyOrImplicitSetter() usage for more info.
3060   return castExpr;
3061 }
3062 
3063 bool RewriteObjC::BufferContainsPPDirectives(const char *startBuf,
3064                                              const char *endBuf) {
3065   while (startBuf < endBuf) {
3066     if (*startBuf == '#') {
3067       // Skip whitespace.
3068       for (++startBuf; startBuf[0] == ' ' || startBuf[0] == '\t'; ++startBuf)
3069         ;
3070       if (!strncmp(startBuf, "if", strlen("if")) ||
3071           !strncmp(startBuf, "ifdef", strlen("ifdef")) ||
3072           !strncmp(startBuf, "ifndef", strlen("ifndef")) ||
3073           !strncmp(startBuf, "define", strlen("define")) ||
3074           !strncmp(startBuf, "undef", strlen("undef")) ||
3075           !strncmp(startBuf, "else", strlen("else")) ||
3076           !strncmp(startBuf, "elif", strlen("elif")) ||
3077           !strncmp(startBuf, "endif", strlen("endif")) ||
3078           !strncmp(startBuf, "pragma", strlen("pragma")) ||
3079           !strncmp(startBuf, "include", strlen("include")) ||
3080           !strncmp(startBuf, "import", strlen("import")) ||
3081           !strncmp(startBuf, "include_next", strlen("include_next")))
3082         return true;
3083     }
3084     startBuf++;
3085   }
3086   return false;
3087 }
3088 
3089 /// RewriteObjCInternalStruct - Rewrite one internal struct corresponding to
3090 /// an objective-c class with ivars.
3091 void RewriteObjC::RewriteObjCInternalStruct(ObjCInterfaceDecl *CDecl,
3092                                                std::string &Result) {
3093   assert(CDecl && "Class missing in SynthesizeObjCInternalStruct");
3094   assert(CDecl->getName() != "" &&
3095          "Name missing in SynthesizeObjCInternalStruct");
3096   // Do not synthesize more than once.
3097   if (ObjCSynthesizedStructs.count(CDecl))
3098     return;
3099   ObjCInterfaceDecl *RCDecl = CDecl->getSuperClass();
3100   int NumIvars = CDecl->ivar_size();
3101   SourceLocation LocStart = CDecl->getBeginLoc();
3102   SourceLocation LocEnd = CDecl->getEndOfDefinitionLoc();
3103 
3104   const char *startBuf = SM->getCharacterData(LocStart);
3105   const char *endBuf = SM->getCharacterData(LocEnd);
3106 
3107   // If no ivars and no root or if its root, directly or indirectly,
3108   // have no ivars (thus not synthesized) then no need to synthesize this class.
3109   if ((!CDecl->isThisDeclarationADefinition() || NumIvars == 0) &&
3110       (!RCDecl || !ObjCSynthesizedStructs.count(RCDecl))) {
3111     endBuf += Lexer::MeasureTokenLength(LocEnd, *SM, LangOpts);
3112     ReplaceText(LocStart, endBuf-startBuf, Result);
3113     return;
3114   }
3115 
3116   // FIXME: This has potential of causing problem. If
3117   // SynthesizeObjCInternalStruct is ever called recursively.
3118   Result += "\nstruct ";
3119   Result += CDecl->getNameAsString();
3120   if (LangOpts.MicrosoftExt)
3121     Result += "_IMPL";
3122 
3123   if (NumIvars > 0) {
3124     const char *cursor = strchr(startBuf, '{');
3125     assert((cursor && endBuf)
3126            && "SynthesizeObjCInternalStruct - malformed @interface");
3127     // If the buffer contains preprocessor directives, we do more fine-grained
3128     // rewrites. This is intended to fix code that looks like (which occurs in
3129     // NSURL.h, for example):
3130     //
3131     // #ifdef XYZ
3132     // @interface Foo : NSObject
3133     // #else
3134     // @interface FooBar : NSObject
3135     // #endif
3136     // {
3137     //    int i;
3138     // }
3139     // @end
3140     //
3141     // This clause is segregated to avoid breaking the common case.
3142     if (BufferContainsPPDirectives(startBuf, cursor)) {
3143       SourceLocation L = RCDecl ? CDecl->getSuperClassLoc() :
3144                                   CDecl->getAtStartLoc();
3145       const char *endHeader = SM->getCharacterData(L);
3146       endHeader += Lexer::MeasureTokenLength(L, *SM, LangOpts);
3147 
3148       if (CDecl->protocol_begin() != CDecl->protocol_end()) {
3149         // advance to the end of the referenced protocols.
3150         while (endHeader < cursor && *endHeader != '>') endHeader++;
3151         endHeader++;
3152       }
3153       // rewrite the original header
3154       ReplaceText(LocStart, endHeader-startBuf, Result);
3155     } else {
3156       // rewrite the original header *without* disturbing the '{'
3157       ReplaceText(LocStart, cursor-startBuf, Result);
3158     }
3159     if (RCDecl && ObjCSynthesizedStructs.count(RCDecl)) {
3160       Result = "\n    struct ";
3161       Result += RCDecl->getNameAsString();
3162       Result += "_IMPL ";
3163       Result += RCDecl->getNameAsString();
3164       Result += "_IVARS;\n";
3165 
3166       // insert the super class structure definition.
3167       SourceLocation OnePastCurly =
3168         LocStart.getLocWithOffset(cursor-startBuf+1);
3169       InsertText(OnePastCurly, Result);
3170     }
3171     cursor++; // past '{'
3172 
3173     // Now comment out any visibility specifiers.
3174     while (cursor < endBuf) {
3175       if (*cursor == '@') {
3176         SourceLocation atLoc = LocStart.getLocWithOffset(cursor-startBuf);
3177         // Skip whitespace.
3178         for (++cursor; cursor[0] == ' ' || cursor[0] == '\t'; ++cursor)
3179           /*scan*/;
3180 
3181         // FIXME: presence of @public, etc. inside comment results in
3182         // this transformation as well, which is still correct c-code.
3183         if (!strncmp(cursor, "public", strlen("public")) ||
3184             !strncmp(cursor, "private", strlen("private")) ||
3185             !strncmp(cursor, "package", strlen("package")) ||
3186             !strncmp(cursor, "protected", strlen("protected")))
3187           InsertText(atLoc, "// ");
3188       }
3189       // FIXME: If there are cases where '<' is used in ivar declaration part
3190       // of user code, then scan the ivar list and use needToScanForQualifiers
3191       // for type checking.
3192       else if (*cursor == '<') {
3193         SourceLocation atLoc = LocStart.getLocWithOffset(cursor-startBuf);
3194         InsertText(atLoc, "/* ");
3195         cursor = strchr(cursor, '>');
3196         cursor++;
3197         atLoc = LocStart.getLocWithOffset(cursor-startBuf);
3198         InsertText(atLoc, " */");
3199       } else if (*cursor == '^') { // rewrite block specifier.
3200         SourceLocation caretLoc = LocStart.getLocWithOffset(cursor-startBuf);
3201         ReplaceText(caretLoc, 1, "*");
3202       }
3203       cursor++;
3204     }
3205     // Don't forget to add a ';'!!
3206     InsertText(LocEnd.getLocWithOffset(1), ";");
3207   } else { // we don't have any instance variables - insert super struct.
3208     endBuf += Lexer::MeasureTokenLength(LocEnd, *SM, LangOpts);
3209     Result += " {\n    struct ";
3210     Result += RCDecl->getNameAsString();
3211     Result += "_IMPL ";
3212     Result += RCDecl->getNameAsString();
3213     Result += "_IVARS;\n};\n";
3214     ReplaceText(LocStart, endBuf-startBuf, Result);
3215   }
3216   // Mark this struct as having been generated.
3217   if (!ObjCSynthesizedStructs.insert(CDecl).second)
3218     llvm_unreachable("struct already synthesize- SynthesizeObjCInternalStruct");
3219 }
3220 
3221 //===----------------------------------------------------------------------===//
3222 // Meta Data Emission
3223 //===----------------------------------------------------------------------===//
3224 
3225 /// RewriteImplementations - This routine rewrites all method implementations
3226 /// and emits meta-data.
3227 
3228 void RewriteObjC::RewriteImplementations() {
3229   int ClsDefCount = ClassImplementation.size();
3230   int CatDefCount = CategoryImplementation.size();
3231 
3232   // Rewrite implemented methods
3233   for (int i = 0; i < ClsDefCount; i++)
3234     RewriteImplementationDecl(ClassImplementation[i]);
3235 
3236   for (int i = 0; i < CatDefCount; i++)
3237     RewriteImplementationDecl(CategoryImplementation[i]);
3238 }
3239 
3240 void RewriteObjC::RewriteByRefString(std::string &ResultStr,
3241                                      const std::string &Name,
3242                                      ValueDecl *VD, bool def) {
3243   assert(BlockByRefDeclNo.count(VD) &&
3244          "RewriteByRefString: ByRef decl missing");
3245   if (def)
3246     ResultStr += "struct ";
3247   ResultStr += "__Block_byref_" + Name +
3248     "_" + utostr(BlockByRefDeclNo[VD]) ;
3249 }
3250 
3251 static bool HasLocalVariableExternalStorage(ValueDecl *VD) {
3252   if (VarDecl *Var = dyn_cast<VarDecl>(VD))
3253     return (Var->isFunctionOrMethodVarDecl() && !Var->hasLocalStorage());
3254   return false;
3255 }
3256 
3257 std::string RewriteObjC::SynthesizeBlockFunc(BlockExpr *CE, int i,
3258                                                    StringRef funcName,
3259                                                    std::string Tag) {
3260   const FunctionType *AFT = CE->getFunctionType();
3261   QualType RT = AFT->getReturnType();
3262   std::string StructRef = "struct " + Tag;
3263   std::string S = "static " + RT.getAsString(Context->getPrintingPolicy()) + " __" +
3264                   funcName.str() + "_" + "block_func_" + utostr(i);
3265 
3266   BlockDecl *BD = CE->getBlockDecl();
3267 
3268   if (isa<FunctionNoProtoType>(AFT)) {
3269     // No user-supplied arguments. Still need to pass in a pointer to the
3270     // block (to reference imported block decl refs).
3271     S += "(" + StructRef + " *__cself)";
3272   } else if (BD->param_empty()) {
3273     S += "(" + StructRef + " *__cself)";
3274   } else {
3275     const FunctionProtoType *FT = cast<FunctionProtoType>(AFT);
3276     assert(FT && "SynthesizeBlockFunc: No function proto");
3277     S += '(';
3278     // first add the implicit argument.
3279     S += StructRef + " *__cself, ";
3280     std::string ParamStr;
3281     for (BlockDecl::param_iterator AI = BD->param_begin(),
3282          E = BD->param_end(); AI != E; ++AI) {
3283       if (AI != BD->param_begin()) S += ", ";
3284       ParamStr = (*AI)->getNameAsString();
3285       QualType QT = (*AI)->getType();
3286       (void)convertBlockPointerToFunctionPointer(QT);
3287       QT.getAsStringInternal(ParamStr, Context->getPrintingPolicy());
3288       S += ParamStr;
3289     }
3290     if (FT->isVariadic()) {
3291       if (!BD->param_empty()) S += ", ";
3292       S += "...";
3293     }
3294     S += ')';
3295   }
3296   S += " {\n";
3297 
3298   // Create local declarations to avoid rewriting all closure decl ref exprs.
3299   // First, emit a declaration for all "by ref" decls.
3300   for (SmallVectorImpl<ValueDecl *>::iterator I = BlockByRefDecls.begin(),
3301        E = BlockByRefDecls.end(); I != E; ++I) {
3302     S += "  ";
3303     std::string Name = (*I)->getNameAsString();
3304     std::string TypeString;
3305     RewriteByRefString(TypeString, Name, (*I));
3306     TypeString += " *";
3307     Name = TypeString + Name;
3308     S += Name + " = __cself->" + (*I)->getNameAsString() + "; // bound by ref\n";
3309   }
3310   // Next, emit a declaration for all "by copy" declarations.
3311   for (SmallVectorImpl<ValueDecl *>::iterator I = BlockByCopyDecls.begin(),
3312        E = BlockByCopyDecls.end(); I != E; ++I) {
3313     S += "  ";
3314     // Handle nested closure invocation. For example:
3315     //
3316     //   void (^myImportedClosure)(void);
3317     //   myImportedClosure  = ^(void) { setGlobalInt(x + y); };
3318     //
3319     //   void (^anotherClosure)(void);
3320     //   anotherClosure = ^(void) {
3321     //     myImportedClosure(); // import and invoke the closure
3322     //   };
3323     //
3324     if (isTopLevelBlockPointerType((*I)->getType())) {
3325       RewriteBlockPointerTypeVariable(S, (*I));
3326       S += " = (";
3327       RewriteBlockPointerType(S, (*I)->getType());
3328       S += ")";
3329       S += "__cself->" + (*I)->getNameAsString() + "; // bound by copy\n";
3330     }
3331     else {
3332       std::string Name = (*I)->getNameAsString();
3333       QualType QT = (*I)->getType();
3334       if (HasLocalVariableExternalStorage(*I))
3335         QT = Context->getPointerType(QT);
3336       QT.getAsStringInternal(Name, Context->getPrintingPolicy());
3337       S += Name + " = __cself->" +
3338                               (*I)->getNameAsString() + "; // bound by copy\n";
3339     }
3340   }
3341   std::string RewrittenStr = RewrittenBlockExprs[CE];
3342   const char *cstr = RewrittenStr.c_str();
3343   while (*cstr++ != '{') ;
3344   S += cstr;
3345   S += "\n";
3346   return S;
3347 }
3348 
3349 std::string RewriteObjC::SynthesizeBlockHelperFuncs(BlockExpr *CE, int i,
3350                                                    StringRef funcName,
3351                                                    std::string Tag) {
3352   std::string StructRef = "struct " + Tag;
3353   std::string S = "static void __";
3354 
3355   S += funcName;
3356   S += "_block_copy_" + utostr(i);
3357   S += "(" + StructRef;
3358   S += "*dst, " + StructRef;
3359   S += "*src) {";
3360   for (ValueDecl *VD : ImportedBlockDecls) {
3361     S += "_Block_object_assign((void*)&dst->";
3362     S += VD->getNameAsString();
3363     S += ", (void*)src->";
3364     S += VD->getNameAsString();
3365     if (BlockByRefDeclsPtrSet.count(VD))
3366       S += ", " + utostr(BLOCK_FIELD_IS_BYREF) + "/*BLOCK_FIELD_IS_BYREF*/);";
3367     else if (VD->getType()->isBlockPointerType())
3368       S += ", " + utostr(BLOCK_FIELD_IS_BLOCK) + "/*BLOCK_FIELD_IS_BLOCK*/);";
3369     else
3370       S += ", " + utostr(BLOCK_FIELD_IS_OBJECT) + "/*BLOCK_FIELD_IS_OBJECT*/);";
3371   }
3372   S += "}\n";
3373 
3374   S += "\nstatic void __";
3375   S += funcName;
3376   S += "_block_dispose_" + utostr(i);
3377   S += "(" + StructRef;
3378   S += "*src) {";
3379   for (ValueDecl *VD : ImportedBlockDecls) {
3380     S += "_Block_object_dispose((void*)src->";
3381     S += VD->getNameAsString();
3382     if (BlockByRefDeclsPtrSet.count(VD))
3383       S += ", " + utostr(BLOCK_FIELD_IS_BYREF) + "/*BLOCK_FIELD_IS_BYREF*/);";
3384     else if (VD->getType()->isBlockPointerType())
3385       S += ", " + utostr(BLOCK_FIELD_IS_BLOCK) + "/*BLOCK_FIELD_IS_BLOCK*/);";
3386     else
3387       S += ", " + utostr(BLOCK_FIELD_IS_OBJECT) + "/*BLOCK_FIELD_IS_OBJECT*/);";
3388   }
3389   S += "}\n";
3390   return S;
3391 }
3392 
3393 std::string RewriteObjC::SynthesizeBlockImpl(BlockExpr *CE, std::string Tag,
3394                                              std::string Desc) {
3395   std::string S = "\nstruct " + Tag;
3396   std::string Constructor = "  " + Tag;
3397 
3398   S += " {\n  struct __block_impl impl;\n";
3399   S += "  struct " + Desc;
3400   S += "* Desc;\n";
3401 
3402   Constructor += "(void *fp, "; // Invoke function pointer.
3403   Constructor += "struct " + Desc; // Descriptor pointer.
3404   Constructor += " *desc";
3405 
3406   if (BlockDeclRefs.size()) {
3407     // Output all "by copy" declarations.
3408     for (SmallVectorImpl<ValueDecl *>::iterator I = BlockByCopyDecls.begin(),
3409          E = BlockByCopyDecls.end(); I != E; ++I) {
3410       S += "  ";
3411       std::string FieldName = (*I)->getNameAsString();
3412       std::string ArgName = "_" + FieldName;
3413       // Handle nested closure invocation. For example:
3414       //
3415       //   void (^myImportedBlock)(void);
3416       //   myImportedBlock  = ^(void) { setGlobalInt(x + y); };
3417       //
3418       //   void (^anotherBlock)(void);
3419       //   anotherBlock = ^(void) {
3420       //     myImportedBlock(); // import and invoke the closure
3421       //   };
3422       //
3423       if (isTopLevelBlockPointerType((*I)->getType())) {
3424         S += "struct __block_impl *";
3425         Constructor += ", void *" + ArgName;
3426       } else {
3427         QualType QT = (*I)->getType();
3428         if (HasLocalVariableExternalStorage(*I))
3429           QT = Context->getPointerType(QT);
3430         QT.getAsStringInternal(FieldName, Context->getPrintingPolicy());
3431         QT.getAsStringInternal(ArgName, Context->getPrintingPolicy());
3432         Constructor += ", " + ArgName;
3433       }
3434       S += FieldName + ";\n";
3435     }
3436     // Output all "by ref" declarations.
3437     for (SmallVectorImpl<ValueDecl *>::iterator I = BlockByRefDecls.begin(),
3438          E = BlockByRefDecls.end(); I != E; ++I) {
3439       S += "  ";
3440       std::string FieldName = (*I)->getNameAsString();
3441       std::string ArgName = "_" + FieldName;
3442       {
3443         std::string TypeString;
3444         RewriteByRefString(TypeString, FieldName, (*I));
3445         TypeString += " *";
3446         FieldName = TypeString + FieldName;
3447         ArgName = TypeString + ArgName;
3448         Constructor += ", " + ArgName;
3449       }
3450       S += FieldName + "; // by ref\n";
3451     }
3452     // Finish writing the constructor.
3453     Constructor += ", int flags=0)";
3454     // Initialize all "by copy" arguments.
3455     bool firsTime = true;
3456     for (SmallVectorImpl<ValueDecl *>::iterator I = BlockByCopyDecls.begin(),
3457          E = BlockByCopyDecls.end(); I != E; ++I) {
3458       std::string Name = (*I)->getNameAsString();
3459         if (firsTime) {
3460           Constructor += " : ";
3461           firsTime = false;
3462         }
3463         else
3464           Constructor += ", ";
3465         if (isTopLevelBlockPointerType((*I)->getType()))
3466           Constructor += Name + "((struct __block_impl *)_" + Name + ")";
3467         else
3468           Constructor += Name + "(_" + Name + ")";
3469     }
3470     // Initialize all "by ref" arguments.
3471     for (SmallVectorImpl<ValueDecl *>::iterator I = BlockByRefDecls.begin(),
3472          E = BlockByRefDecls.end(); I != E; ++I) {
3473       std::string Name = (*I)->getNameAsString();
3474       if (firsTime) {
3475         Constructor += " : ";
3476         firsTime = false;
3477       }
3478       else
3479         Constructor += ", ";
3480       Constructor += Name + "(_" + Name + "->__forwarding)";
3481     }
3482 
3483     Constructor += " {\n";
3484     if (GlobalVarDecl)
3485       Constructor += "    impl.isa = &_NSConcreteGlobalBlock;\n";
3486     else
3487       Constructor += "    impl.isa = &_NSConcreteStackBlock;\n";
3488     Constructor += "    impl.Flags = flags;\n    impl.FuncPtr = fp;\n";
3489 
3490     Constructor += "    Desc = desc;\n";
3491   } else {
3492     // Finish writing the constructor.
3493     Constructor += ", int flags=0) {\n";
3494     if (GlobalVarDecl)
3495       Constructor += "    impl.isa = &_NSConcreteGlobalBlock;\n";
3496     else
3497       Constructor += "    impl.isa = &_NSConcreteStackBlock;\n";
3498     Constructor += "    impl.Flags = flags;\n    impl.FuncPtr = fp;\n";
3499     Constructor += "    Desc = desc;\n";
3500   }
3501   Constructor += "  ";
3502   Constructor += "}\n";
3503   S += Constructor;
3504   S += "};\n";
3505   return S;
3506 }
3507 
3508 std::string RewriteObjC::SynthesizeBlockDescriptor(std::string DescTag,
3509                                                    std::string ImplTag, int i,
3510                                                    StringRef FunName,
3511                                                    unsigned hasCopy) {
3512   std::string S = "\nstatic struct " + DescTag;
3513 
3514   S += " {\n  unsigned long reserved;\n";
3515   S += "  unsigned long Block_size;\n";
3516   if (hasCopy) {
3517     S += "  void (*copy)(struct ";
3518     S += ImplTag; S += "*, struct ";
3519     S += ImplTag; S += "*);\n";
3520 
3521     S += "  void (*dispose)(struct ";
3522     S += ImplTag; S += "*);\n";
3523   }
3524   S += "} ";
3525 
3526   S += DescTag + "_DATA = { 0, sizeof(struct ";
3527   S += ImplTag + ")";
3528   if (hasCopy) {
3529     S += ", __" + FunName.str() + "_block_copy_" + utostr(i);
3530     S += ", __" + FunName.str() + "_block_dispose_" + utostr(i);
3531   }
3532   S += "};\n";
3533   return S;
3534 }
3535 
3536 void RewriteObjC::SynthesizeBlockLiterals(SourceLocation FunLocStart,
3537                                           StringRef FunName) {
3538   // Insert declaration for the function in which block literal is used.
3539   if (CurFunctionDeclToDeclareForBlock && !Blocks.empty())
3540     RewriteBlockLiteralFunctionDecl(CurFunctionDeclToDeclareForBlock);
3541   bool RewriteSC = (GlobalVarDecl &&
3542                     !Blocks.empty() &&
3543                     GlobalVarDecl->getStorageClass() == SC_Static &&
3544                     GlobalVarDecl->getType().getCVRQualifiers());
3545   if (RewriteSC) {
3546     std::string SC(" void __");
3547     SC += GlobalVarDecl->getNameAsString();
3548     SC += "() {}";
3549     InsertText(FunLocStart, SC);
3550   }
3551 
3552   // Insert closures that were part of the function.
3553   for (unsigned i = 0, count=0; i < Blocks.size(); i++) {
3554     CollectBlockDeclRefInfo(Blocks[i]);
3555     // Need to copy-in the inner copied-in variables not actually used in this
3556     // block.
3557     for (int j = 0; j < InnerDeclRefsCount[i]; j++) {
3558       DeclRefExpr *Exp = InnerDeclRefs[count++];
3559       ValueDecl *VD = Exp->getDecl();
3560       BlockDeclRefs.push_back(Exp);
3561       if (!VD->hasAttr<BlocksAttr>() && !BlockByCopyDeclsPtrSet.count(VD)) {
3562         BlockByCopyDeclsPtrSet.insert(VD);
3563         BlockByCopyDecls.push_back(VD);
3564       }
3565       if (VD->hasAttr<BlocksAttr>() && !BlockByRefDeclsPtrSet.count(VD)) {
3566         BlockByRefDeclsPtrSet.insert(VD);
3567         BlockByRefDecls.push_back(VD);
3568       }
3569       // imported objects in the inner blocks not used in the outer
3570       // blocks must be copied/disposed in the outer block as well.
3571       if (VD->hasAttr<BlocksAttr>() ||
3572           VD->getType()->isObjCObjectPointerType() ||
3573           VD->getType()->isBlockPointerType())
3574         ImportedBlockDecls.insert(VD);
3575     }
3576 
3577     std::string ImplTag = "__" + FunName.str() + "_block_impl_" + utostr(i);
3578     std::string DescTag = "__" + FunName.str() + "_block_desc_" + utostr(i);
3579 
3580     std::string CI = SynthesizeBlockImpl(Blocks[i], ImplTag, DescTag);
3581 
3582     InsertText(FunLocStart, CI);
3583 
3584     std::string CF = SynthesizeBlockFunc(Blocks[i], i, FunName, ImplTag);
3585 
3586     InsertText(FunLocStart, CF);
3587 
3588     if (ImportedBlockDecls.size()) {
3589       std::string HF = SynthesizeBlockHelperFuncs(Blocks[i], i, FunName, ImplTag);
3590       InsertText(FunLocStart, HF);
3591     }
3592     std::string BD = SynthesizeBlockDescriptor(DescTag, ImplTag, i, FunName,
3593                                                ImportedBlockDecls.size() > 0);
3594     InsertText(FunLocStart, BD);
3595 
3596     BlockDeclRefs.clear();
3597     BlockByRefDecls.clear();
3598     BlockByRefDeclsPtrSet.clear();
3599     BlockByCopyDecls.clear();
3600     BlockByCopyDeclsPtrSet.clear();
3601     ImportedBlockDecls.clear();
3602   }
3603   if (RewriteSC) {
3604     // Must insert any 'const/volatile/static here. Since it has been
3605     // removed as result of rewriting of block literals.
3606     std::string SC;
3607     if (GlobalVarDecl->getStorageClass() == SC_Static)
3608       SC = "static ";
3609     if (GlobalVarDecl->getType().isConstQualified())
3610       SC += "const ";
3611     if (GlobalVarDecl->getType().isVolatileQualified())
3612       SC += "volatile ";
3613     if (GlobalVarDecl->getType().isRestrictQualified())
3614       SC += "restrict ";
3615     InsertText(FunLocStart, SC);
3616   }
3617 
3618   Blocks.clear();
3619   InnerDeclRefsCount.clear();
3620   InnerDeclRefs.clear();
3621   RewrittenBlockExprs.clear();
3622 }
3623 
3624 void RewriteObjC::InsertBlockLiteralsWithinFunction(FunctionDecl *FD) {
3625   SourceLocation FunLocStart = FD->getTypeSpecStartLoc();
3626   StringRef FuncName = FD->getName();
3627 
3628   SynthesizeBlockLiterals(FunLocStart, FuncName);
3629 }
3630 
3631 static void BuildUniqueMethodName(std::string &Name,
3632                                   ObjCMethodDecl *MD) {
3633   ObjCInterfaceDecl *IFace = MD->getClassInterface();
3634   Name = IFace->getName();
3635   Name += "__" + MD->getSelector().getAsString();
3636   // Convert colons to underscores.
3637   std::string::size_type loc = 0;
3638   while ((loc = Name.find(':', loc)) != std::string::npos)
3639     Name.replace(loc, 1, "_");
3640 }
3641 
3642 void RewriteObjC::InsertBlockLiteralsWithinMethod(ObjCMethodDecl *MD) {
3643   // fprintf(stderr,"In InsertBlockLiteralsWitinMethod\n");
3644   // SourceLocation FunLocStart = MD->getBeginLoc();
3645   SourceLocation FunLocStart = MD->getBeginLoc();
3646   std::string FuncName;
3647   BuildUniqueMethodName(FuncName, MD);
3648   SynthesizeBlockLiterals(FunLocStart, FuncName);
3649 }
3650 
3651 void RewriteObjC::GetBlockDeclRefExprs(Stmt *S) {
3652   for (Stmt *SubStmt : S->children())
3653     if (SubStmt) {
3654       if (BlockExpr *CBE = dyn_cast<BlockExpr>(SubStmt))
3655         GetBlockDeclRefExprs(CBE->getBody());
3656       else
3657         GetBlockDeclRefExprs(SubStmt);
3658     }
3659   // Handle specific things.
3660   if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(S))
3661     if (DRE->refersToEnclosingVariableOrCapture() ||
3662         HasLocalVariableExternalStorage(DRE->getDecl()))
3663       // FIXME: Handle enums.
3664       BlockDeclRefs.push_back(DRE);
3665 }
3666 
3667 void RewriteObjC::GetInnerBlockDeclRefExprs(Stmt *S,
3668                 SmallVectorImpl<DeclRefExpr *> &InnerBlockDeclRefs,
3669                 llvm::SmallPtrSetImpl<const DeclContext *> &InnerContexts) {
3670   for (Stmt *SubStmt : S->children())
3671     if (SubStmt) {
3672       if (BlockExpr *CBE = dyn_cast<BlockExpr>(SubStmt)) {
3673         InnerContexts.insert(cast<DeclContext>(CBE->getBlockDecl()));
3674         GetInnerBlockDeclRefExprs(CBE->getBody(),
3675                                   InnerBlockDeclRefs,
3676                                   InnerContexts);
3677       }
3678       else
3679         GetInnerBlockDeclRefExprs(SubStmt, InnerBlockDeclRefs, InnerContexts);
3680     }
3681   // Handle specific things.
3682   if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(S)) {
3683     if (DRE->refersToEnclosingVariableOrCapture() ||
3684         HasLocalVariableExternalStorage(DRE->getDecl())) {
3685       if (!InnerContexts.count(DRE->getDecl()->getDeclContext()))
3686         InnerBlockDeclRefs.push_back(DRE);
3687       if (VarDecl *Var = cast<VarDecl>(DRE->getDecl()))
3688         if (Var->isFunctionOrMethodVarDecl())
3689           ImportedLocalExternalDecls.insert(Var);
3690     }
3691   }
3692 }
3693 
3694 /// convertFunctionTypeOfBlocks - This routine converts a function type
3695 /// whose result type may be a block pointer or whose argument type(s)
3696 /// might be block pointers to an equivalent function type replacing
3697 /// all block pointers to function pointers.
3698 QualType RewriteObjC::convertFunctionTypeOfBlocks(const FunctionType *FT) {
3699   const FunctionProtoType *FTP = dyn_cast<FunctionProtoType>(FT);
3700   // FTP will be null for closures that don't take arguments.
3701   // Generate a funky cast.
3702   SmallVector<QualType, 8> ArgTypes;
3703   QualType Res = FT->getReturnType();
3704   bool HasBlockType = convertBlockPointerToFunctionPointer(Res);
3705 
3706   if (FTP) {
3707     for (auto &I : FTP->param_types()) {
3708       QualType t = I;
3709       // Make sure we convert "t (^)(...)" to "t (*)(...)".
3710       if (convertBlockPointerToFunctionPointer(t))
3711         HasBlockType = true;
3712       ArgTypes.push_back(t);
3713     }
3714   }
3715   QualType FuncType;
3716   // FIXME. Does this work if block takes no argument but has a return type
3717   // which is of block type?
3718   if (HasBlockType)
3719     FuncType = getSimpleFunctionType(Res, ArgTypes);
3720   else FuncType = QualType(FT, 0);
3721   return FuncType;
3722 }
3723 
3724 Stmt *RewriteObjC::SynthesizeBlockCall(CallExpr *Exp, const Expr *BlockExp) {
3725   // Navigate to relevant type information.
3726   const BlockPointerType *CPT = nullptr;
3727 
3728   if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(BlockExp)) {
3729     CPT = DRE->getType()->getAs<BlockPointerType>();
3730   } else if (const MemberExpr *MExpr = dyn_cast<MemberExpr>(BlockExp)) {
3731     CPT = MExpr->getType()->getAs<BlockPointerType>();
3732   }
3733   else if (const ParenExpr *PRE = dyn_cast<ParenExpr>(BlockExp)) {
3734     return SynthesizeBlockCall(Exp, PRE->getSubExpr());
3735   }
3736   else if (const ImplicitCastExpr *IEXPR = dyn_cast<ImplicitCastExpr>(BlockExp))
3737     CPT = IEXPR->getType()->getAs<BlockPointerType>();
3738   else if (const ConditionalOperator *CEXPR =
3739             dyn_cast<ConditionalOperator>(BlockExp)) {
3740     Expr *LHSExp = CEXPR->getLHS();
3741     Stmt *LHSStmt = SynthesizeBlockCall(Exp, LHSExp);
3742     Expr *RHSExp = CEXPR->getRHS();
3743     Stmt *RHSStmt = SynthesizeBlockCall(Exp, RHSExp);
3744     Expr *CONDExp = CEXPR->getCond();
3745     ConditionalOperator *CondExpr =
3746       new (Context) ConditionalOperator(CONDExp,
3747                                       SourceLocation(), cast<Expr>(LHSStmt),
3748                                       SourceLocation(), cast<Expr>(RHSStmt),
3749                                       Exp->getType(), VK_RValue, OK_Ordinary);
3750     return CondExpr;
3751   } else if (const ObjCIvarRefExpr *IRE = dyn_cast<ObjCIvarRefExpr>(BlockExp)) {
3752     CPT = IRE->getType()->getAs<BlockPointerType>();
3753   } else if (const PseudoObjectExpr *POE
3754                = dyn_cast<PseudoObjectExpr>(BlockExp)) {
3755     CPT = POE->getType()->castAs<BlockPointerType>();
3756   } else {
3757     assert(false && "RewriteBlockClass: Bad type");
3758   }
3759   assert(CPT && "RewriteBlockClass: Bad type");
3760   const FunctionType *FT = CPT->getPointeeType()->getAs<FunctionType>();
3761   assert(FT && "RewriteBlockClass: Bad type");
3762   const FunctionProtoType *FTP = dyn_cast<FunctionProtoType>(FT);
3763   // FTP will be null for closures that don't take arguments.
3764 
3765   RecordDecl *RD = RecordDecl::Create(*Context, TTK_Struct, TUDecl,
3766                                       SourceLocation(), SourceLocation(),
3767                                       &Context->Idents.get("__block_impl"));
3768   QualType PtrBlock = Context->getPointerType(Context->getTagDeclType(RD));
3769 
3770   // Generate a funky cast.
3771   SmallVector<QualType, 8> ArgTypes;
3772 
3773   // Push the block argument type.
3774   ArgTypes.push_back(PtrBlock);
3775   if (FTP) {
3776     for (auto &I : FTP->param_types()) {
3777       QualType t = I;
3778       // Make sure we convert "t (^)(...)" to "t (*)(...)".
3779       if (!convertBlockPointerToFunctionPointer(t))
3780         convertToUnqualifiedObjCType(t);
3781       ArgTypes.push_back(t);
3782     }
3783   }
3784   // Now do the pointer to function cast.
3785   QualType PtrToFuncCastType = getSimpleFunctionType(Exp->getType(), ArgTypes);
3786 
3787   PtrToFuncCastType = Context->getPointerType(PtrToFuncCastType);
3788 
3789   CastExpr *BlkCast = NoTypeInfoCStyleCastExpr(Context, PtrBlock,
3790                                                CK_BitCast,
3791                                                const_cast<Expr*>(BlockExp));
3792   // Don't forget the parens to enforce the proper binding.
3793   ParenExpr *PE = new (Context) ParenExpr(SourceLocation(), SourceLocation(),
3794                                           BlkCast);
3795   //PE->dump();
3796 
3797   FieldDecl *FD = FieldDecl::Create(*Context, nullptr, SourceLocation(),
3798                                     SourceLocation(),
3799                                     &Context->Idents.get("FuncPtr"),
3800                                     Context->VoidPtrTy, nullptr,
3801                                     /*BitWidth=*/nullptr, /*Mutable=*/true,
3802                                     ICIS_NoInit);
3803   MemberExpr *ME = MemberExpr::CreateImplicit(
3804       *Context, PE, true, FD, FD->getType(), VK_LValue, OK_Ordinary);
3805 
3806   CastExpr *FunkCast = NoTypeInfoCStyleCastExpr(Context, PtrToFuncCastType,
3807                                                 CK_BitCast, ME);
3808   PE = new (Context) ParenExpr(SourceLocation(), SourceLocation(), FunkCast);
3809 
3810   SmallVector<Expr*, 8> BlkExprs;
3811   // Add the implicit argument.
3812   BlkExprs.push_back(BlkCast);
3813   // Add the user arguments.
3814   for (CallExpr::arg_iterator I = Exp->arg_begin(),
3815        E = Exp->arg_end(); I != E; ++I) {
3816     BlkExprs.push_back(*I);
3817   }
3818   CallExpr *CE = CallExpr::Create(*Context, PE, BlkExprs, Exp->getType(),
3819                                   VK_RValue, SourceLocation());
3820   return CE;
3821 }
3822 
3823 // We need to return the rewritten expression to handle cases where the
3824 // BlockDeclRefExpr is embedded in another expression being rewritten.
3825 // For example:
3826 //
3827 // int main() {
3828 //    __block Foo *f;
3829 //    __block int i;
3830 //
3831 //    void (^myblock)() = ^() {
3832 //        [f test]; // f is a BlockDeclRefExpr embedded in a message (which is being rewritten).
3833 //        i = 77;
3834 //    };
3835 //}
3836 Stmt *RewriteObjC::RewriteBlockDeclRefExpr(DeclRefExpr *DeclRefExp) {
3837   // Rewrite the byref variable into BYREFVAR->__forwarding->BYREFVAR
3838   // for each DeclRefExp where BYREFVAR is name of the variable.
3839   ValueDecl *VD = DeclRefExp->getDecl();
3840   bool isArrow = DeclRefExp->refersToEnclosingVariableOrCapture() ||
3841                  HasLocalVariableExternalStorage(DeclRefExp->getDecl());
3842 
3843   FieldDecl *FD = FieldDecl::Create(*Context, nullptr, SourceLocation(),
3844                                     SourceLocation(),
3845                                     &Context->Idents.get("__forwarding"),
3846                                     Context->VoidPtrTy, nullptr,
3847                                     /*BitWidth=*/nullptr, /*Mutable=*/true,
3848                                     ICIS_NoInit);
3849   MemberExpr *ME =
3850       MemberExpr::CreateImplicit(*Context, DeclRefExp, isArrow, FD,
3851                                  FD->getType(), VK_LValue, OK_Ordinary);
3852 
3853   StringRef Name = VD->getName();
3854   FD = FieldDecl::Create(*Context, nullptr, SourceLocation(), SourceLocation(),
3855                          &Context->Idents.get(Name),
3856                          Context->VoidPtrTy, nullptr,
3857                          /*BitWidth=*/nullptr, /*Mutable=*/true,
3858                          ICIS_NoInit);
3859   ME = MemberExpr::CreateImplicit(*Context, ME, true, FD, DeclRefExp->getType(),
3860                                   VK_LValue, OK_Ordinary);
3861 
3862   // Need parens to enforce precedence.
3863   ParenExpr *PE = new (Context) ParenExpr(DeclRefExp->getExprLoc(),
3864                                           DeclRefExp->getExprLoc(),
3865                                           ME);
3866   ReplaceStmt(DeclRefExp, PE);
3867   return PE;
3868 }
3869 
3870 // Rewrites the imported local variable V with external storage
3871 // (static, extern, etc.) as *V
3872 //
3873 Stmt *RewriteObjC::RewriteLocalVariableExternalStorage(DeclRefExpr *DRE) {
3874   ValueDecl *VD = DRE->getDecl();
3875   if (VarDecl *Var = dyn_cast<VarDecl>(VD))
3876     if (!ImportedLocalExternalDecls.count(Var))
3877       return DRE;
3878   Expr *Exp = new (Context) UnaryOperator(DRE, UO_Deref, DRE->getType(),
3879                                           VK_LValue, OK_Ordinary,
3880                                           DRE->getLocation(), false);
3881   // Need parens to enforce precedence.
3882   ParenExpr *PE = new (Context) ParenExpr(SourceLocation(), SourceLocation(),
3883                                           Exp);
3884   ReplaceStmt(DRE, PE);
3885   return PE;
3886 }
3887 
3888 void RewriteObjC::RewriteCastExpr(CStyleCastExpr *CE) {
3889   SourceLocation LocStart = CE->getLParenLoc();
3890   SourceLocation LocEnd = CE->getRParenLoc();
3891 
3892   // Need to avoid trying to rewrite synthesized casts.
3893   if (LocStart.isInvalid())
3894     return;
3895   // Need to avoid trying to rewrite casts contained in macros.
3896   if (!Rewriter::isRewritable(LocStart) || !Rewriter::isRewritable(LocEnd))
3897     return;
3898 
3899   const char *startBuf = SM->getCharacterData(LocStart);
3900   const char *endBuf = SM->getCharacterData(LocEnd);
3901   QualType QT = CE->getType();
3902   const Type* TypePtr = QT->getAs<Type>();
3903   if (isa<TypeOfExprType>(TypePtr)) {
3904     const TypeOfExprType *TypeOfExprTypePtr = cast<TypeOfExprType>(TypePtr);
3905     QT = TypeOfExprTypePtr->getUnderlyingExpr()->getType();
3906     std::string TypeAsString = "(";
3907     RewriteBlockPointerType(TypeAsString, QT);
3908     TypeAsString += ")";
3909     ReplaceText(LocStart, endBuf-startBuf+1, TypeAsString);
3910     return;
3911   }
3912   // advance the location to startArgList.
3913   const char *argPtr = startBuf;
3914 
3915   while (*argPtr++ && (argPtr < endBuf)) {
3916     switch (*argPtr) {
3917     case '^':
3918       // Replace the '^' with '*'.
3919       LocStart = LocStart.getLocWithOffset(argPtr-startBuf);
3920       ReplaceText(LocStart, 1, "*");
3921       break;
3922     }
3923   }
3924 }
3925 
3926 void RewriteObjC::RewriteBlockPointerFunctionArgs(FunctionDecl *FD) {
3927   SourceLocation DeclLoc = FD->getLocation();
3928   unsigned parenCount = 0;
3929 
3930   // We have 1 or more arguments that have closure pointers.
3931   const char *startBuf = SM->getCharacterData(DeclLoc);
3932   const char *startArgList = strchr(startBuf, '(');
3933 
3934   assert((*startArgList == '(') && "Rewriter fuzzy parser confused");
3935 
3936   parenCount++;
3937   // advance the location to startArgList.
3938   DeclLoc = DeclLoc.getLocWithOffset(startArgList-startBuf);
3939   assert((DeclLoc.isValid()) && "Invalid DeclLoc");
3940 
3941   const char *argPtr = startArgList;
3942 
3943   while (*argPtr++ && parenCount) {
3944     switch (*argPtr) {
3945     case '^':
3946       // Replace the '^' with '*'.
3947       DeclLoc = DeclLoc.getLocWithOffset(argPtr-startArgList);
3948       ReplaceText(DeclLoc, 1, "*");
3949       break;
3950     case '(':
3951       parenCount++;
3952       break;
3953     case ')':
3954       parenCount--;
3955       break;
3956     }
3957   }
3958 }
3959 
3960 bool RewriteObjC::PointerTypeTakesAnyBlockArguments(QualType QT) {
3961   const FunctionProtoType *FTP;
3962   const PointerType *PT = QT->getAs<PointerType>();
3963   if (PT) {
3964     FTP = PT->getPointeeType()->getAs<FunctionProtoType>();
3965   } else {
3966     const BlockPointerType *BPT = QT->getAs<BlockPointerType>();
3967     assert(BPT && "BlockPointerTypeTakeAnyBlockArguments(): not a block pointer type");
3968     FTP = BPT->getPointeeType()->getAs<FunctionProtoType>();
3969   }
3970   if (FTP) {
3971     for (const auto &I : FTP->param_types())
3972       if (isTopLevelBlockPointerType(I))
3973         return true;
3974   }
3975   return false;
3976 }
3977 
3978 bool RewriteObjC::PointerTypeTakesAnyObjCQualifiedType(QualType QT) {
3979   const FunctionProtoType *FTP;
3980   const PointerType *PT = QT->getAs<PointerType>();
3981   if (PT) {
3982     FTP = PT->getPointeeType()->getAs<FunctionProtoType>();
3983   } else {
3984     const BlockPointerType *BPT = QT->getAs<BlockPointerType>();
3985     assert(BPT && "BlockPointerTypeTakeAnyBlockArguments(): not a block pointer type");
3986     FTP = BPT->getPointeeType()->getAs<FunctionProtoType>();
3987   }
3988   if (FTP) {
3989     for (const auto &I : FTP->param_types()) {
3990       if (I->isObjCQualifiedIdType())
3991         return true;
3992       if (I->isObjCObjectPointerType() &&
3993           I->getPointeeType()->isObjCQualifiedInterfaceType())
3994         return true;
3995     }
3996 
3997   }
3998   return false;
3999 }
4000 
4001 void RewriteObjC::GetExtentOfArgList(const char *Name, const char *&LParen,
4002                                      const char *&RParen) {
4003   const char *argPtr = strchr(Name, '(');
4004   assert((*argPtr == '(') && "Rewriter fuzzy parser confused");
4005 
4006   LParen = argPtr; // output the start.
4007   argPtr++; // skip past the left paren.
4008   unsigned parenCount = 1;
4009 
4010   while (*argPtr && parenCount) {
4011     switch (*argPtr) {
4012     case '(': parenCount++; break;
4013     case ')': parenCount--; break;
4014     default: break;
4015     }
4016     if (parenCount) argPtr++;
4017   }
4018   assert((*argPtr == ')') && "Rewriter fuzzy parser confused");
4019   RParen = argPtr; // output the end
4020 }
4021 
4022 void RewriteObjC::RewriteBlockPointerDecl(NamedDecl *ND) {
4023   if (FunctionDecl *FD = dyn_cast<FunctionDecl>(ND)) {
4024     RewriteBlockPointerFunctionArgs(FD);
4025     return;
4026   }
4027   // Handle Variables and Typedefs.
4028   SourceLocation DeclLoc = ND->getLocation();
4029   QualType DeclT;
4030   if (VarDecl *VD = dyn_cast<VarDecl>(ND))
4031     DeclT = VD->getType();
4032   else if (TypedefNameDecl *TDD = dyn_cast<TypedefNameDecl>(ND))
4033     DeclT = TDD->getUnderlyingType();
4034   else if (FieldDecl *FD = dyn_cast<FieldDecl>(ND))
4035     DeclT = FD->getType();
4036   else
4037     llvm_unreachable("RewriteBlockPointerDecl(): Decl type not yet handled");
4038 
4039   const char *startBuf = SM->getCharacterData(DeclLoc);
4040   const char *endBuf = startBuf;
4041   // scan backward (from the decl location) for the end of the previous decl.
4042   while (*startBuf != '^' && *startBuf != ';' && startBuf != MainFileStart)
4043     startBuf--;
4044   SourceLocation Start = DeclLoc.getLocWithOffset(startBuf-endBuf);
4045   std::string buf;
4046   unsigned OrigLength=0;
4047   // *startBuf != '^' if we are dealing with a pointer to function that
4048   // may take block argument types (which will be handled below).
4049   if (*startBuf == '^') {
4050     // Replace the '^' with '*', computing a negative offset.
4051     buf = '*';
4052     startBuf++;
4053     OrigLength++;
4054   }
4055   while (*startBuf != ')') {
4056     buf += *startBuf;
4057     startBuf++;
4058     OrigLength++;
4059   }
4060   buf += ')';
4061   OrigLength++;
4062 
4063   if (PointerTypeTakesAnyBlockArguments(DeclT) ||
4064       PointerTypeTakesAnyObjCQualifiedType(DeclT)) {
4065     // Replace the '^' with '*' for arguments.
4066     // Replace id<P> with id/*<>*/
4067     DeclLoc = ND->getLocation();
4068     startBuf = SM->getCharacterData(DeclLoc);
4069     const char *argListBegin, *argListEnd;
4070     GetExtentOfArgList(startBuf, argListBegin, argListEnd);
4071     while (argListBegin < argListEnd) {
4072       if (*argListBegin == '^')
4073         buf += '*';
4074       else if (*argListBegin ==  '<') {
4075         buf += "/*";
4076         buf += *argListBegin++;
4077         OrigLength++;
4078         while (*argListBegin != '>') {
4079           buf += *argListBegin++;
4080           OrigLength++;
4081         }
4082         buf += *argListBegin;
4083         buf += "*/";
4084       }
4085       else
4086         buf += *argListBegin;
4087       argListBegin++;
4088       OrigLength++;
4089     }
4090     buf += ')';
4091     OrigLength++;
4092   }
4093   ReplaceText(Start, OrigLength, buf);
4094 }
4095 
4096 /// SynthesizeByrefCopyDestroyHelper - This routine synthesizes:
4097 /// void __Block_byref_id_object_copy(struct Block_byref_id_object *dst,
4098 ///                    struct Block_byref_id_object *src) {
4099 ///  _Block_object_assign (&_dest->object, _src->object,
4100 ///                        BLOCK_BYREF_CALLER | BLOCK_FIELD_IS_OBJECT
4101 ///                        [|BLOCK_FIELD_IS_WEAK]) // object
4102 ///  _Block_object_assign(&_dest->object, _src->object,
4103 ///                       BLOCK_BYREF_CALLER | BLOCK_FIELD_IS_BLOCK
4104 ///                       [|BLOCK_FIELD_IS_WEAK]) // block
4105 /// }
4106 /// And:
4107 /// void __Block_byref_id_object_dispose(struct Block_byref_id_object *_src) {
4108 ///  _Block_object_dispose(_src->object,
4109 ///                        BLOCK_BYREF_CALLER | BLOCK_FIELD_IS_OBJECT
4110 ///                        [|BLOCK_FIELD_IS_WEAK]) // object
4111 ///  _Block_object_dispose(_src->object,
4112 ///                         BLOCK_BYREF_CALLER | BLOCK_FIELD_IS_BLOCK
4113 ///                         [|BLOCK_FIELD_IS_WEAK]) // block
4114 /// }
4115 
4116 std::string RewriteObjC::SynthesizeByrefCopyDestroyHelper(VarDecl *VD,
4117                                                           int flag) {
4118   std::string S;
4119   if (CopyDestroyCache.count(flag))
4120     return S;
4121   CopyDestroyCache.insert(flag);
4122   S = "static void __Block_byref_id_object_copy_";
4123   S += utostr(flag);
4124   S += "(void *dst, void *src) {\n";
4125 
4126   // offset into the object pointer is computed as:
4127   // void * + void* + int + int + void* + void *
4128   unsigned IntSize =
4129   static_cast<unsigned>(Context->getTypeSize(Context->IntTy));
4130   unsigned VoidPtrSize =
4131   static_cast<unsigned>(Context->getTypeSize(Context->VoidPtrTy));
4132 
4133   unsigned offset = (VoidPtrSize*4 + IntSize + IntSize)/Context->getCharWidth();
4134   S += " _Block_object_assign((char*)dst + ";
4135   S += utostr(offset);
4136   S += ", *(void * *) ((char*)src + ";
4137   S += utostr(offset);
4138   S += "), ";
4139   S += utostr(flag);
4140   S += ");\n}\n";
4141 
4142   S += "static void __Block_byref_id_object_dispose_";
4143   S += utostr(flag);
4144   S += "(void *src) {\n";
4145   S += " _Block_object_dispose(*(void * *) ((char*)src + ";
4146   S += utostr(offset);
4147   S += "), ";
4148   S += utostr(flag);
4149   S += ");\n}\n";
4150   return S;
4151 }
4152 
4153 /// RewriteByRefVar - For each __block typex ND variable this routine transforms
4154 /// the declaration into:
4155 /// struct __Block_byref_ND {
4156 /// void *__isa;                  // NULL for everything except __weak pointers
4157 /// struct __Block_byref_ND *__forwarding;
4158 /// int32_t __flags;
4159 /// int32_t __size;
4160 /// void *__Block_byref_id_object_copy; // If variable is __block ObjC object
4161 /// void *__Block_byref_id_object_dispose; // If variable is __block ObjC object
4162 /// typex ND;
4163 /// };
4164 ///
4165 /// It then replaces declaration of ND variable with:
4166 /// struct __Block_byref_ND ND = {__isa=0B, __forwarding=&ND, __flags=some_flag,
4167 ///                               __size=sizeof(struct __Block_byref_ND),
4168 ///                               ND=initializer-if-any};
4169 ///
4170 ///
4171 void RewriteObjC::RewriteByRefVar(VarDecl *ND) {
4172   // Insert declaration for the function in which block literal is
4173   // used.
4174   if (CurFunctionDeclToDeclareForBlock)
4175     RewriteBlockLiteralFunctionDecl(CurFunctionDeclToDeclareForBlock);
4176   int flag = 0;
4177   int isa = 0;
4178   SourceLocation DeclLoc = ND->getTypeSpecStartLoc();
4179   if (DeclLoc.isInvalid())
4180     // If type location is missing, it is because of missing type (a warning).
4181     // Use variable's location which is good for this case.
4182     DeclLoc = ND->getLocation();
4183   const char *startBuf = SM->getCharacterData(DeclLoc);
4184   SourceLocation X = ND->getEndLoc();
4185   X = SM->getExpansionLoc(X);
4186   const char *endBuf = SM->getCharacterData(X);
4187   std::string Name(ND->getNameAsString());
4188   std::string ByrefType;
4189   RewriteByRefString(ByrefType, Name, ND, true);
4190   ByrefType += " {\n";
4191   ByrefType += "  void *__isa;\n";
4192   RewriteByRefString(ByrefType, Name, ND);
4193   ByrefType += " *__forwarding;\n";
4194   ByrefType += " int __flags;\n";
4195   ByrefType += " int __size;\n";
4196   // Add void *__Block_byref_id_object_copy;
4197   // void *__Block_byref_id_object_dispose; if needed.
4198   QualType Ty = ND->getType();
4199   bool HasCopyAndDispose = Context->BlockRequiresCopying(Ty, ND);
4200   if (HasCopyAndDispose) {
4201     ByrefType += " void (*__Block_byref_id_object_copy)(void*, void*);\n";
4202     ByrefType += " void (*__Block_byref_id_object_dispose)(void*);\n";
4203   }
4204 
4205   QualType T = Ty;
4206   (void)convertBlockPointerToFunctionPointer(T);
4207   T.getAsStringInternal(Name, Context->getPrintingPolicy());
4208 
4209   ByrefType += " " + Name + ";\n";
4210   ByrefType += "};\n";
4211   // Insert this type in global scope. It is needed by helper function.
4212   SourceLocation FunLocStart;
4213   if (CurFunctionDef)
4214      FunLocStart = CurFunctionDef->getTypeSpecStartLoc();
4215   else {
4216     assert(CurMethodDef && "RewriteByRefVar - CurMethodDef is null");
4217     FunLocStart = CurMethodDef->getBeginLoc();
4218   }
4219   InsertText(FunLocStart, ByrefType);
4220   if (Ty.isObjCGCWeak()) {
4221     flag |= BLOCK_FIELD_IS_WEAK;
4222     isa = 1;
4223   }
4224 
4225   if (HasCopyAndDispose) {
4226     flag = BLOCK_BYREF_CALLER;
4227     QualType Ty = ND->getType();
4228     // FIXME. Handle __weak variable (BLOCK_FIELD_IS_WEAK) as well.
4229     if (Ty->isBlockPointerType())
4230       flag |= BLOCK_FIELD_IS_BLOCK;
4231     else
4232       flag |= BLOCK_FIELD_IS_OBJECT;
4233     std::string HF = SynthesizeByrefCopyDestroyHelper(ND, flag);
4234     if (!HF.empty())
4235       InsertText(FunLocStart, HF);
4236   }
4237 
4238   // struct __Block_byref_ND ND =
4239   // {0, &ND, some_flag, __size=sizeof(struct __Block_byref_ND),
4240   //  initializer-if-any};
4241   bool hasInit = (ND->getInit() != nullptr);
4242   unsigned flags = 0;
4243   if (HasCopyAndDispose)
4244     flags |= BLOCK_HAS_COPY_DISPOSE;
4245   Name = ND->getNameAsString();
4246   ByrefType.clear();
4247   RewriteByRefString(ByrefType, Name, ND);
4248   std::string ForwardingCastType("(");
4249   ForwardingCastType += ByrefType + " *)";
4250   if (!hasInit) {
4251     ByrefType += " " + Name + " = {(void*)";
4252     ByrefType += utostr(isa);
4253     ByrefType += "," +  ForwardingCastType + "&" + Name + ", ";
4254     ByrefType += utostr(flags);
4255     ByrefType += ", ";
4256     ByrefType += "sizeof(";
4257     RewriteByRefString(ByrefType, Name, ND);
4258     ByrefType += ")";
4259     if (HasCopyAndDispose) {
4260       ByrefType += ", __Block_byref_id_object_copy_";
4261       ByrefType += utostr(flag);
4262       ByrefType += ", __Block_byref_id_object_dispose_";
4263       ByrefType += utostr(flag);
4264     }
4265     ByrefType += "};\n";
4266     unsigned nameSize = Name.size();
4267     // for block or function pointer declaration. Name is already
4268     // part of the declaration.
4269     if (Ty->isBlockPointerType() || Ty->isFunctionPointerType())
4270       nameSize = 1;
4271     ReplaceText(DeclLoc, endBuf-startBuf+nameSize, ByrefType);
4272   }
4273   else {
4274     SourceLocation startLoc;
4275     Expr *E = ND->getInit();
4276     if (const CStyleCastExpr *ECE = dyn_cast<CStyleCastExpr>(E))
4277       startLoc = ECE->getLParenLoc();
4278     else
4279       startLoc = E->getBeginLoc();
4280     startLoc = SM->getExpansionLoc(startLoc);
4281     endBuf = SM->getCharacterData(startLoc);
4282     ByrefType += " " + Name;
4283     ByrefType += " = {(void*)";
4284     ByrefType += utostr(isa);
4285     ByrefType += "," +  ForwardingCastType + "&" + Name + ", ";
4286     ByrefType += utostr(flags);
4287     ByrefType += ", ";
4288     ByrefType += "sizeof(";
4289     RewriteByRefString(ByrefType, Name, ND);
4290     ByrefType += "), ";
4291     if (HasCopyAndDispose) {
4292       ByrefType += "__Block_byref_id_object_copy_";
4293       ByrefType += utostr(flag);
4294       ByrefType += ", __Block_byref_id_object_dispose_";
4295       ByrefType += utostr(flag);
4296       ByrefType += ", ";
4297     }
4298     ReplaceText(DeclLoc, endBuf-startBuf, ByrefType);
4299 
4300     // Complete the newly synthesized compound expression by inserting a right
4301     // curly brace before the end of the declaration.
4302     // FIXME: This approach avoids rewriting the initializer expression. It
4303     // also assumes there is only one declarator. For example, the following
4304     // isn't currently supported by this routine (in general):
4305     //
4306     // double __block BYREFVAR = 1.34, BYREFVAR2 = 1.37;
4307     //
4308     const char *startInitializerBuf = SM->getCharacterData(startLoc);
4309     const char *semiBuf = strchr(startInitializerBuf, ';');
4310     assert((*semiBuf == ';') && "RewriteByRefVar: can't find ';'");
4311     SourceLocation semiLoc =
4312       startLoc.getLocWithOffset(semiBuf-startInitializerBuf);
4313 
4314     InsertText(semiLoc, "}");
4315   }
4316 }
4317 
4318 void RewriteObjC::CollectBlockDeclRefInfo(BlockExpr *Exp) {
4319   // Add initializers for any closure decl refs.
4320   GetBlockDeclRefExprs(Exp->getBody());
4321   if (BlockDeclRefs.size()) {
4322     // Unique all "by copy" declarations.
4323     for (unsigned i = 0; i < BlockDeclRefs.size(); i++)
4324       if (!BlockDeclRefs[i]->getDecl()->hasAttr<BlocksAttr>()) {
4325         if (!BlockByCopyDeclsPtrSet.count(BlockDeclRefs[i]->getDecl())) {
4326           BlockByCopyDeclsPtrSet.insert(BlockDeclRefs[i]->getDecl());
4327           BlockByCopyDecls.push_back(BlockDeclRefs[i]->getDecl());
4328         }
4329       }
4330     // Unique all "by ref" declarations.
4331     for (unsigned i = 0; i < BlockDeclRefs.size(); i++)
4332       if (BlockDeclRefs[i]->getDecl()->hasAttr<BlocksAttr>()) {
4333         if (!BlockByRefDeclsPtrSet.count(BlockDeclRefs[i]->getDecl())) {
4334           BlockByRefDeclsPtrSet.insert(BlockDeclRefs[i]->getDecl());
4335           BlockByRefDecls.push_back(BlockDeclRefs[i]->getDecl());
4336         }
4337       }
4338     // Find any imported blocks...they will need special attention.
4339     for (unsigned i = 0; i < BlockDeclRefs.size(); i++)
4340       if (BlockDeclRefs[i]->getDecl()->hasAttr<BlocksAttr>() ||
4341           BlockDeclRefs[i]->getType()->isObjCObjectPointerType() ||
4342           BlockDeclRefs[i]->getType()->isBlockPointerType())
4343         ImportedBlockDecls.insert(BlockDeclRefs[i]->getDecl());
4344   }
4345 }
4346 
4347 FunctionDecl *RewriteObjC::SynthBlockInitFunctionDecl(StringRef name) {
4348   IdentifierInfo *ID = &Context->Idents.get(name);
4349   QualType FType = Context->getFunctionNoProtoType(Context->VoidPtrTy);
4350   return FunctionDecl::Create(*Context, TUDecl, SourceLocation(),
4351                               SourceLocation(), ID, FType, nullptr, SC_Extern,
4352                               false, false);
4353 }
4354 
4355 Stmt *RewriteObjC::SynthBlockInitExpr(BlockExpr *Exp,
4356                      const SmallVectorImpl<DeclRefExpr *> &InnerBlockDeclRefs) {
4357   const BlockDecl *block = Exp->getBlockDecl();
4358   Blocks.push_back(Exp);
4359 
4360   CollectBlockDeclRefInfo(Exp);
4361 
4362   // Add inner imported variables now used in current block.
4363  int countOfInnerDecls = 0;
4364   if (!InnerBlockDeclRefs.empty()) {
4365     for (unsigned i = 0; i < InnerBlockDeclRefs.size(); i++) {
4366       DeclRefExpr *Exp = InnerBlockDeclRefs[i];
4367       ValueDecl *VD = Exp->getDecl();
4368       if (!VD->hasAttr<BlocksAttr>() && !BlockByCopyDeclsPtrSet.count(VD)) {
4369       // We need to save the copied-in variables in nested
4370       // blocks because it is needed at the end for some of the API generations.
4371       // See SynthesizeBlockLiterals routine.
4372         InnerDeclRefs.push_back(Exp); countOfInnerDecls++;
4373         BlockDeclRefs.push_back(Exp);
4374         BlockByCopyDeclsPtrSet.insert(VD);
4375         BlockByCopyDecls.push_back(VD);
4376       }
4377       if (VD->hasAttr<BlocksAttr>() && !BlockByRefDeclsPtrSet.count(VD)) {
4378         InnerDeclRefs.push_back(Exp); countOfInnerDecls++;
4379         BlockDeclRefs.push_back(Exp);
4380         BlockByRefDeclsPtrSet.insert(VD);
4381         BlockByRefDecls.push_back(VD);
4382       }
4383     }
4384     // Find any imported blocks...they will need special attention.
4385     for (unsigned i = 0; i < InnerBlockDeclRefs.size(); i++)
4386       if (InnerBlockDeclRefs[i]->getDecl()->hasAttr<BlocksAttr>() ||
4387           InnerBlockDeclRefs[i]->getType()->isObjCObjectPointerType() ||
4388           InnerBlockDeclRefs[i]->getType()->isBlockPointerType())
4389         ImportedBlockDecls.insert(InnerBlockDeclRefs[i]->getDecl());
4390   }
4391   InnerDeclRefsCount.push_back(countOfInnerDecls);
4392 
4393   std::string FuncName;
4394 
4395   if (CurFunctionDef)
4396     FuncName = CurFunctionDef->getNameAsString();
4397   else if (CurMethodDef)
4398     BuildUniqueMethodName(FuncName, CurMethodDef);
4399   else if (GlobalVarDecl)
4400     FuncName = std::string(GlobalVarDecl->getNameAsString());
4401 
4402   std::string BlockNumber = utostr(Blocks.size()-1);
4403 
4404   std::string Tag = "__" + FuncName + "_block_impl_" + BlockNumber;
4405   std::string Func = "__" + FuncName + "_block_func_" + BlockNumber;
4406 
4407   // Get a pointer to the function type so we can cast appropriately.
4408   QualType BFT = convertFunctionTypeOfBlocks(Exp->getFunctionType());
4409   QualType FType = Context->getPointerType(BFT);
4410 
4411   FunctionDecl *FD;
4412   Expr *NewRep;
4413 
4414   // Simulate a constructor call...
4415   FD = SynthBlockInitFunctionDecl(Tag);
4416   DeclRefExpr *DRE = new (Context)
4417       DeclRefExpr(*Context, FD, false, FType, VK_RValue, SourceLocation());
4418 
4419   SmallVector<Expr*, 4> InitExprs;
4420 
4421   // Initialize the block function.
4422   FD = SynthBlockInitFunctionDecl(Func);
4423   DeclRefExpr *Arg = new (Context) DeclRefExpr(
4424       *Context, FD, false, FD->getType(), VK_LValue, SourceLocation());
4425   CastExpr *castExpr =
4426       NoTypeInfoCStyleCastExpr(Context, Context->VoidPtrTy, CK_BitCast, Arg);
4427   InitExprs.push_back(castExpr);
4428 
4429   // Initialize the block descriptor.
4430   std::string DescData = "__" + FuncName + "_block_desc_" + BlockNumber + "_DATA";
4431 
4432   VarDecl *NewVD = VarDecl::Create(
4433       *Context, TUDecl, SourceLocation(), SourceLocation(),
4434       &Context->Idents.get(DescData), Context->VoidPtrTy, nullptr, SC_Static);
4435   UnaryOperator *DescRefExpr = new (Context) UnaryOperator(
4436       new (Context) DeclRefExpr(*Context, NewVD, false, Context->VoidPtrTy,
4437                                 VK_LValue, SourceLocation()),
4438       UO_AddrOf, Context->getPointerType(Context->VoidPtrTy), VK_RValue,
4439       OK_Ordinary, SourceLocation(), false);
4440   InitExprs.push_back(DescRefExpr);
4441 
4442   // Add initializers for any closure decl refs.
4443   if (BlockDeclRefs.size()) {
4444     Expr *Exp;
4445     // Output all "by copy" declarations.
4446     for (SmallVectorImpl<ValueDecl *>::iterator I = BlockByCopyDecls.begin(),
4447          E = BlockByCopyDecls.end(); I != E; ++I) {
4448       if (isObjCType((*I)->getType())) {
4449         // FIXME: Conform to ABI ([[obj retain] autorelease]).
4450         FD = SynthBlockInitFunctionDecl((*I)->getName());
4451         Exp = new (Context) DeclRefExpr(*Context, FD, false, FD->getType(),
4452                                         VK_LValue, SourceLocation());
4453         if (HasLocalVariableExternalStorage(*I)) {
4454           QualType QT = (*I)->getType();
4455           QT = Context->getPointerType(QT);
4456           Exp = new (Context) UnaryOperator(Exp, UO_AddrOf, QT, VK_RValue,
4457                                             OK_Ordinary, SourceLocation(),
4458                                             false);
4459         }
4460       } else if (isTopLevelBlockPointerType((*I)->getType())) {
4461         FD = SynthBlockInitFunctionDecl((*I)->getName());
4462         Arg = new (Context) DeclRefExpr(*Context, FD, false, FD->getType(),
4463                                         VK_LValue, SourceLocation());
4464         Exp = NoTypeInfoCStyleCastExpr(Context, Context->VoidPtrTy, CK_BitCast,
4465                                        Arg);
4466       } else {
4467         FD = SynthBlockInitFunctionDecl((*I)->getName());
4468         Exp = new (Context) DeclRefExpr(*Context, FD, false, FD->getType(),
4469                                         VK_LValue, SourceLocation());
4470         if (HasLocalVariableExternalStorage(*I)) {
4471           QualType QT = (*I)->getType();
4472           QT = Context->getPointerType(QT);
4473           Exp = new (Context) UnaryOperator(Exp, UO_AddrOf, QT, VK_RValue,
4474                                             OK_Ordinary, SourceLocation(),
4475                                             false);
4476         }
4477       }
4478       InitExprs.push_back(Exp);
4479     }
4480     // Output all "by ref" declarations.
4481     for (SmallVectorImpl<ValueDecl *>::iterator I = BlockByRefDecls.begin(),
4482          E = BlockByRefDecls.end(); I != E; ++I) {
4483       ValueDecl *ND = (*I);
4484       std::string Name(ND->getNameAsString());
4485       std::string RecName;
4486       RewriteByRefString(RecName, Name, ND, true);
4487       IdentifierInfo *II = &Context->Idents.get(RecName.c_str()
4488                                                 + sizeof("struct"));
4489       RecordDecl *RD = RecordDecl::Create(*Context, TTK_Struct, TUDecl,
4490                                           SourceLocation(), SourceLocation(),
4491                                           II);
4492       assert(RD && "SynthBlockInitExpr(): Can't find RecordDecl");
4493       QualType castT = Context->getPointerType(Context->getTagDeclType(RD));
4494 
4495       FD = SynthBlockInitFunctionDecl((*I)->getName());
4496       Exp = new (Context) DeclRefExpr(*Context, FD, false, FD->getType(),
4497                                       VK_LValue, SourceLocation());
4498       bool isNestedCapturedVar = false;
4499       if (block)
4500         for (const auto &CI : block->captures()) {
4501           const VarDecl *variable = CI.getVariable();
4502           if (variable == ND && CI.isNested()) {
4503             assert (CI.isByRef() &&
4504                     "SynthBlockInitExpr - captured block variable is not byref");
4505             isNestedCapturedVar = true;
4506             break;
4507           }
4508         }
4509       // captured nested byref variable has its address passed. Do not take
4510       // its address again.
4511       if (!isNestedCapturedVar)
4512         Exp = new (Context) UnaryOperator(
4513             Exp, UO_AddrOf, Context->getPointerType(Exp->getType()), VK_RValue,
4514             OK_Ordinary, SourceLocation(), false);
4515       Exp = NoTypeInfoCStyleCastExpr(Context, castT, CK_BitCast, Exp);
4516       InitExprs.push_back(Exp);
4517     }
4518   }
4519   if (ImportedBlockDecls.size()) {
4520     // generate BLOCK_HAS_COPY_DISPOSE(have helper funcs) | BLOCK_HAS_DESCRIPTOR
4521     int flag = (BLOCK_HAS_COPY_DISPOSE | BLOCK_HAS_DESCRIPTOR);
4522     unsigned IntSize =
4523       static_cast<unsigned>(Context->getTypeSize(Context->IntTy));
4524     Expr *FlagExp = IntegerLiteral::Create(*Context, llvm::APInt(IntSize, flag),
4525                                            Context->IntTy, SourceLocation());
4526     InitExprs.push_back(FlagExp);
4527   }
4528   NewRep = CallExpr::Create(*Context, DRE, InitExprs, FType, VK_LValue,
4529                             SourceLocation());
4530   NewRep = new (Context) UnaryOperator(
4531       NewRep, UO_AddrOf, Context->getPointerType(NewRep->getType()), VK_RValue,
4532       OK_Ordinary, SourceLocation(), false);
4533   NewRep = NoTypeInfoCStyleCastExpr(Context, FType, CK_BitCast,
4534                                     NewRep);
4535   BlockDeclRefs.clear();
4536   BlockByRefDecls.clear();
4537   BlockByRefDeclsPtrSet.clear();
4538   BlockByCopyDecls.clear();
4539   BlockByCopyDeclsPtrSet.clear();
4540   ImportedBlockDecls.clear();
4541   return NewRep;
4542 }
4543 
4544 bool RewriteObjC::IsDeclStmtInForeachHeader(DeclStmt *DS) {
4545   if (const ObjCForCollectionStmt * CS =
4546       dyn_cast<ObjCForCollectionStmt>(Stmts.back()))
4547         return CS->getElement() == DS;
4548   return false;
4549 }
4550 
4551 //===----------------------------------------------------------------------===//
4552 // Function Body / Expression rewriting
4553 //===----------------------------------------------------------------------===//
4554 
4555 Stmt *RewriteObjC::RewriteFunctionBodyOrGlobalInitializer(Stmt *S) {
4556   if (isa<SwitchStmt>(S) || isa<WhileStmt>(S) ||
4557       isa<DoStmt>(S) || isa<ForStmt>(S))
4558     Stmts.push_back(S);
4559   else if (isa<ObjCForCollectionStmt>(S)) {
4560     Stmts.push_back(S);
4561     ObjCBcLabelNo.push_back(++BcLabelCount);
4562   }
4563 
4564   // Pseudo-object operations and ivar references need special
4565   // treatment because we're going to recursively rewrite them.
4566   if (PseudoObjectExpr *PseudoOp = dyn_cast<PseudoObjectExpr>(S)) {
4567     if (isa<BinaryOperator>(PseudoOp->getSyntacticForm())) {
4568       return RewritePropertyOrImplicitSetter(PseudoOp);
4569     } else {
4570       return RewritePropertyOrImplicitGetter(PseudoOp);
4571     }
4572   } else if (ObjCIvarRefExpr *IvarRefExpr = dyn_cast<ObjCIvarRefExpr>(S)) {
4573     return RewriteObjCIvarRefExpr(IvarRefExpr);
4574   }
4575 
4576   SourceRange OrigStmtRange = S->getSourceRange();
4577 
4578   // Perform a bottom up rewrite of all children.
4579   for (Stmt *&childStmt : S->children())
4580     if (childStmt) {
4581       Stmt *newStmt = RewriteFunctionBodyOrGlobalInitializer(childStmt);
4582       if (newStmt) {
4583         childStmt = newStmt;
4584       }
4585     }
4586 
4587   if (BlockExpr *BE = dyn_cast<BlockExpr>(S)) {
4588     SmallVector<DeclRefExpr *, 8> InnerBlockDeclRefs;
4589     llvm::SmallPtrSet<const DeclContext *, 8> InnerContexts;
4590     InnerContexts.insert(BE->getBlockDecl());
4591     ImportedLocalExternalDecls.clear();
4592     GetInnerBlockDeclRefExprs(BE->getBody(),
4593                               InnerBlockDeclRefs, InnerContexts);
4594     // Rewrite the block body in place.
4595     Stmt *SaveCurrentBody = CurrentBody;
4596     CurrentBody = BE->getBody();
4597     PropParentMap = nullptr;
4598     // block literal on rhs of a property-dot-sytax assignment
4599     // must be replaced by its synthesize ast so getRewrittenText
4600     // works as expected. In this case, what actually ends up on RHS
4601     // is the blockTranscribed which is the helper function for the
4602     // block literal; as in: self.c = ^() {[ace ARR];};
4603     bool saveDisableReplaceStmt = DisableReplaceStmt;
4604     DisableReplaceStmt = false;
4605     RewriteFunctionBodyOrGlobalInitializer(BE->getBody());
4606     DisableReplaceStmt = saveDisableReplaceStmt;
4607     CurrentBody = SaveCurrentBody;
4608     PropParentMap = nullptr;
4609     ImportedLocalExternalDecls.clear();
4610     // Now we snarf the rewritten text and stash it away for later use.
4611     std::string Str = Rewrite.getRewrittenText(BE->getSourceRange());
4612     RewrittenBlockExprs[BE] = Str;
4613 
4614     Stmt *blockTranscribed = SynthBlockInitExpr(BE, InnerBlockDeclRefs);
4615 
4616     //blockTranscribed->dump();
4617     ReplaceStmt(S, blockTranscribed);
4618     return blockTranscribed;
4619   }
4620   // Handle specific things.
4621   if (ObjCEncodeExpr *AtEncode = dyn_cast<ObjCEncodeExpr>(S))
4622     return RewriteAtEncode(AtEncode);
4623 
4624   if (ObjCSelectorExpr *AtSelector = dyn_cast<ObjCSelectorExpr>(S))
4625     return RewriteAtSelector(AtSelector);
4626 
4627   if (ObjCStringLiteral *AtString = dyn_cast<ObjCStringLiteral>(S))
4628     return RewriteObjCStringLiteral(AtString);
4629 
4630   if (ObjCMessageExpr *MessExpr = dyn_cast<ObjCMessageExpr>(S)) {
4631 #if 0
4632     // Before we rewrite it, put the original message expression in a comment.
4633     SourceLocation startLoc = MessExpr->getBeginLoc();
4634     SourceLocation endLoc = MessExpr->getEndLoc();
4635 
4636     const char *startBuf = SM->getCharacterData(startLoc);
4637     const char *endBuf = SM->getCharacterData(endLoc);
4638 
4639     std::string messString;
4640     messString += "// ";
4641     messString.append(startBuf, endBuf-startBuf+1);
4642     messString += "\n";
4643 
4644     // FIXME: Missing definition of
4645     // InsertText(clang::SourceLocation, char const*, unsigned int).
4646     // InsertText(startLoc, messString);
4647     // Tried this, but it didn't work either...
4648     // ReplaceText(startLoc, 0, messString.c_str(), messString.size());
4649 #endif
4650     return RewriteMessageExpr(MessExpr);
4651   }
4652 
4653   if (ObjCAtTryStmt *StmtTry = dyn_cast<ObjCAtTryStmt>(S))
4654     return RewriteObjCTryStmt(StmtTry);
4655 
4656   if (ObjCAtSynchronizedStmt *StmtTry = dyn_cast<ObjCAtSynchronizedStmt>(S))
4657     return RewriteObjCSynchronizedStmt(StmtTry);
4658 
4659   if (ObjCAtThrowStmt *StmtThrow = dyn_cast<ObjCAtThrowStmt>(S))
4660     return RewriteObjCThrowStmt(StmtThrow);
4661 
4662   if (ObjCProtocolExpr *ProtocolExp = dyn_cast<ObjCProtocolExpr>(S))
4663     return RewriteObjCProtocolExpr(ProtocolExp);
4664 
4665   if (ObjCForCollectionStmt *StmtForCollection =
4666         dyn_cast<ObjCForCollectionStmt>(S))
4667     return RewriteObjCForCollectionStmt(StmtForCollection,
4668                                         OrigStmtRange.getEnd());
4669   if (BreakStmt *StmtBreakStmt =
4670       dyn_cast<BreakStmt>(S))
4671     return RewriteBreakStmt(StmtBreakStmt);
4672   if (ContinueStmt *StmtContinueStmt =
4673       dyn_cast<ContinueStmt>(S))
4674     return RewriteContinueStmt(StmtContinueStmt);
4675 
4676   // Need to check for protocol refs (id <P>, Foo <P> *) in variable decls
4677   // and cast exprs.
4678   if (DeclStmt *DS = dyn_cast<DeclStmt>(S)) {
4679     // FIXME: What we're doing here is modifying the type-specifier that
4680     // precedes the first Decl.  In the future the DeclGroup should have
4681     // a separate type-specifier that we can rewrite.
4682     // NOTE: We need to avoid rewriting the DeclStmt if it is within
4683     // the context of an ObjCForCollectionStmt. For example:
4684     //   NSArray *someArray;
4685     //   for (id <FooProtocol> index in someArray) ;
4686     // This is because RewriteObjCForCollectionStmt() does textual rewriting
4687     // and it depends on the original text locations/positions.
4688     if (Stmts.empty() || !IsDeclStmtInForeachHeader(DS))
4689       RewriteObjCQualifiedInterfaceTypes(*DS->decl_begin());
4690 
4691     // Blocks rewrite rules.
4692     for (auto *SD : DS->decls()) {
4693       if (ValueDecl *ND = dyn_cast<ValueDecl>(SD)) {
4694         if (isTopLevelBlockPointerType(ND->getType()))
4695           RewriteBlockPointerDecl(ND);
4696         else if (ND->getType()->isFunctionPointerType())
4697           CheckFunctionPointerDecl(ND->getType(), ND);
4698         if (VarDecl *VD = dyn_cast<VarDecl>(SD)) {
4699           if (VD->hasAttr<BlocksAttr>()) {
4700             static unsigned uniqueByrefDeclCount = 0;
4701             assert(!BlockByRefDeclNo.count(ND) &&
4702               "RewriteFunctionBodyOrGlobalInitializer: Duplicate byref decl");
4703             BlockByRefDeclNo[ND] = uniqueByrefDeclCount++;
4704             RewriteByRefVar(VD);
4705           }
4706           else
4707             RewriteTypeOfDecl(VD);
4708         }
4709       }
4710       if (TypedefNameDecl *TD = dyn_cast<TypedefNameDecl>(SD)) {
4711         if (isTopLevelBlockPointerType(TD->getUnderlyingType()))
4712           RewriteBlockPointerDecl(TD);
4713         else if (TD->getUnderlyingType()->isFunctionPointerType())
4714           CheckFunctionPointerDecl(TD->getUnderlyingType(), TD);
4715       }
4716     }
4717   }
4718 
4719   if (CStyleCastExpr *CE = dyn_cast<CStyleCastExpr>(S))
4720     RewriteObjCQualifiedInterfaceTypes(CE);
4721 
4722   if (isa<SwitchStmt>(S) || isa<WhileStmt>(S) ||
4723       isa<DoStmt>(S) || isa<ForStmt>(S)) {
4724     assert(!Stmts.empty() && "Statement stack is empty");
4725     assert ((isa<SwitchStmt>(Stmts.back()) || isa<WhileStmt>(Stmts.back()) ||
4726              isa<DoStmt>(Stmts.back()) || isa<ForStmt>(Stmts.back()))
4727             && "Statement stack mismatch");
4728     Stmts.pop_back();
4729   }
4730   // Handle blocks rewriting.
4731   if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(S)) {
4732     ValueDecl *VD = DRE->getDecl();
4733     if (VD->hasAttr<BlocksAttr>())
4734       return RewriteBlockDeclRefExpr(DRE);
4735     if (HasLocalVariableExternalStorage(VD))
4736       return RewriteLocalVariableExternalStorage(DRE);
4737   }
4738 
4739   if (CallExpr *CE = dyn_cast<CallExpr>(S)) {
4740     if (CE->getCallee()->getType()->isBlockPointerType()) {
4741       Stmt *BlockCall = SynthesizeBlockCall(CE, CE->getCallee());
4742       ReplaceStmt(S, BlockCall);
4743       return BlockCall;
4744     }
4745   }
4746   if (CStyleCastExpr *CE = dyn_cast<CStyleCastExpr>(S)) {
4747     RewriteCastExpr(CE);
4748   }
4749 #if 0
4750   if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(S)) {
4751     CastExpr *Replacement = new (Context) CastExpr(ICE->getType(),
4752                                                    ICE->getSubExpr(),
4753                                                    SourceLocation());
4754     // Get the new text.
4755     std::string SStr;
4756     llvm::raw_string_ostream Buf(SStr);
4757     Replacement->printPretty(Buf);
4758     const std::string &Str = Buf.str();
4759 
4760     printf("CAST = %s\n", &Str[0]);
4761     InsertText(ICE->getSubExpr()->getBeginLoc(), Str);
4762     delete S;
4763     return Replacement;
4764   }
4765 #endif
4766   // Return this stmt unmodified.
4767   return S;
4768 }
4769 
4770 void RewriteObjC::RewriteRecordBody(RecordDecl *RD) {
4771   for (auto *FD : RD->fields()) {
4772     if (isTopLevelBlockPointerType(FD->getType()))
4773       RewriteBlockPointerDecl(FD);
4774     if (FD->getType()->isObjCQualifiedIdType() ||
4775         FD->getType()->isObjCQualifiedInterfaceType())
4776       RewriteObjCQualifiedInterfaceTypes(FD);
4777   }
4778 }
4779 
4780 /// HandleDeclInMainFile - This is called for each top-level decl defined in the
4781 /// main file of the input.
4782 void RewriteObjC::HandleDeclInMainFile(Decl *D) {
4783   switch (D->getKind()) {
4784     case Decl::Function: {
4785       FunctionDecl *FD = cast<FunctionDecl>(D);
4786       if (FD->isOverloadedOperator())
4787         return;
4788 
4789       // Since function prototypes don't have ParmDecl's, we check the function
4790       // prototype. This enables us to rewrite function declarations and
4791       // definitions using the same code.
4792       RewriteBlocksInFunctionProtoType(FD->getType(), FD);
4793 
4794       if (!FD->isThisDeclarationADefinition())
4795         break;
4796 
4797       // FIXME: If this should support Obj-C++, support CXXTryStmt
4798       if (CompoundStmt *Body = dyn_cast_or_null<CompoundStmt>(FD->getBody())) {
4799         CurFunctionDef = FD;
4800         CurFunctionDeclToDeclareForBlock = FD;
4801         CurrentBody = Body;
4802         Body =
4803         cast_or_null<CompoundStmt>(RewriteFunctionBodyOrGlobalInitializer(Body));
4804         FD->setBody(Body);
4805         CurrentBody = nullptr;
4806         if (PropParentMap) {
4807           delete PropParentMap;
4808           PropParentMap = nullptr;
4809         }
4810         // This synthesizes and inserts the block "impl" struct, invoke function,
4811         // and any copy/dispose helper functions.
4812         InsertBlockLiteralsWithinFunction(FD);
4813         CurFunctionDef = nullptr;
4814         CurFunctionDeclToDeclareForBlock = nullptr;
4815       }
4816       break;
4817     }
4818     case Decl::ObjCMethod: {
4819       ObjCMethodDecl *MD = cast<ObjCMethodDecl>(D);
4820       if (CompoundStmt *Body = MD->getCompoundBody()) {
4821         CurMethodDef = MD;
4822         CurrentBody = Body;
4823         Body =
4824           cast_or_null<CompoundStmt>(RewriteFunctionBodyOrGlobalInitializer(Body));
4825         MD->setBody(Body);
4826         CurrentBody = nullptr;
4827         if (PropParentMap) {
4828           delete PropParentMap;
4829           PropParentMap = nullptr;
4830         }
4831         InsertBlockLiteralsWithinMethod(MD);
4832         CurMethodDef = nullptr;
4833       }
4834       break;
4835     }
4836     case Decl::ObjCImplementation: {
4837       ObjCImplementationDecl *CI = cast<ObjCImplementationDecl>(D);
4838       ClassImplementation.push_back(CI);
4839       break;
4840     }
4841     case Decl::ObjCCategoryImpl: {
4842       ObjCCategoryImplDecl *CI = cast<ObjCCategoryImplDecl>(D);
4843       CategoryImplementation.push_back(CI);
4844       break;
4845     }
4846     case Decl::Var: {
4847       VarDecl *VD = cast<VarDecl>(D);
4848       RewriteObjCQualifiedInterfaceTypes(VD);
4849       if (isTopLevelBlockPointerType(VD->getType()))
4850         RewriteBlockPointerDecl(VD);
4851       else if (VD->getType()->isFunctionPointerType()) {
4852         CheckFunctionPointerDecl(VD->getType(), VD);
4853         if (VD->getInit()) {
4854           if (CStyleCastExpr *CE = dyn_cast<CStyleCastExpr>(VD->getInit())) {
4855             RewriteCastExpr(CE);
4856           }
4857         }
4858       } else if (VD->getType()->isRecordType()) {
4859         RecordDecl *RD = VD->getType()->castAs<RecordType>()->getDecl();
4860         if (RD->isCompleteDefinition())
4861           RewriteRecordBody(RD);
4862       }
4863       if (VD->getInit()) {
4864         GlobalVarDecl = VD;
4865         CurrentBody = VD->getInit();
4866         RewriteFunctionBodyOrGlobalInitializer(VD->getInit());
4867         CurrentBody = nullptr;
4868         if (PropParentMap) {
4869           delete PropParentMap;
4870           PropParentMap = nullptr;
4871         }
4872         SynthesizeBlockLiterals(VD->getTypeSpecStartLoc(), VD->getName());
4873         GlobalVarDecl = nullptr;
4874 
4875         // This is needed for blocks.
4876         if (CStyleCastExpr *CE = dyn_cast<CStyleCastExpr>(VD->getInit())) {
4877             RewriteCastExpr(CE);
4878         }
4879       }
4880       break;
4881     }
4882     case Decl::TypeAlias:
4883     case Decl::Typedef: {
4884       if (TypedefNameDecl *TD = dyn_cast<TypedefNameDecl>(D)) {
4885         if (isTopLevelBlockPointerType(TD->getUnderlyingType()))
4886           RewriteBlockPointerDecl(TD);
4887         else if (TD->getUnderlyingType()->isFunctionPointerType())
4888           CheckFunctionPointerDecl(TD->getUnderlyingType(), TD);
4889       }
4890       break;
4891     }
4892     case Decl::CXXRecord:
4893     case Decl::Record: {
4894       RecordDecl *RD = cast<RecordDecl>(D);
4895       if (RD->isCompleteDefinition())
4896         RewriteRecordBody(RD);
4897       break;
4898     }
4899     default:
4900       break;
4901   }
4902   // Nothing yet.
4903 }
4904 
4905 void RewriteObjC::HandleTranslationUnit(ASTContext &C) {
4906   if (Diags.hasErrorOccurred())
4907     return;
4908 
4909   RewriteInclude();
4910 
4911   // Here's a great place to add any extra declarations that may be needed.
4912   // Write out meta data for each @protocol(<expr>).
4913   for (ObjCProtocolDecl *ProtDecl : ProtocolExprDecls)
4914     RewriteObjCProtocolMetaData(ProtDecl, "", "", Preamble);
4915 
4916   InsertText(SM->getLocForStartOfFile(MainFileID), Preamble, false);
4917   if (ClassImplementation.size() || CategoryImplementation.size())
4918     RewriteImplementations();
4919 
4920   // Get the buffer corresponding to MainFileID.  If we haven't changed it, then
4921   // we are done.
4922   if (const RewriteBuffer *RewriteBuf =
4923       Rewrite.getRewriteBufferFor(MainFileID)) {
4924     //printf("Changed:\n");
4925     *OutFile << std::string(RewriteBuf->begin(), RewriteBuf->end());
4926   } else {
4927     llvm::errs() << "No changes\n";
4928   }
4929 
4930   if (ClassImplementation.size() || CategoryImplementation.size() ||
4931       ProtocolExprDecls.size()) {
4932     // Rewrite Objective-c meta data*
4933     std::string ResultStr;
4934     RewriteMetaDataIntoBuffer(ResultStr);
4935     // Emit metadata.
4936     *OutFile << ResultStr;
4937   }
4938   OutFile->flush();
4939 }
4940 
4941 void RewriteObjCFragileABI::Initialize(ASTContext &context) {
4942   InitializeCommon(context);
4943 
4944   // declaring objc_selector outside the parameter list removes a silly
4945   // scope related warning...
4946   if (IsHeader)
4947     Preamble = "#pragma once\n";
4948   Preamble += "struct objc_selector; struct objc_class;\n";
4949   Preamble += "struct __rw_objc_super { struct objc_object *object; ";
4950   Preamble += "struct objc_object *superClass; ";
4951   if (LangOpts.MicrosoftExt) {
4952     // Add a constructor for creating temporary objects.
4953     Preamble += "__rw_objc_super(struct objc_object *o, struct objc_object *s) "
4954     ": ";
4955     Preamble += "object(o), superClass(s) {} ";
4956   }
4957   Preamble += "};\n";
4958   Preamble += "#ifndef _REWRITER_typedef_Protocol\n";
4959   Preamble += "typedef struct objc_object Protocol;\n";
4960   Preamble += "#define _REWRITER_typedef_Protocol\n";
4961   Preamble += "#endif\n";
4962   if (LangOpts.MicrosoftExt) {
4963     Preamble += "#define __OBJC_RW_DLLIMPORT extern \"C\" __declspec(dllimport)\n";
4964     Preamble += "#define __OBJC_RW_STATICIMPORT extern \"C\"\n";
4965   } else
4966     Preamble += "#define __OBJC_RW_DLLIMPORT extern\n";
4967   Preamble += "__OBJC_RW_DLLIMPORT struct objc_object *objc_msgSend";
4968   Preamble += "(struct objc_object *, struct objc_selector *, ...);\n";
4969   Preamble += "__OBJC_RW_DLLIMPORT struct objc_object *objc_msgSendSuper";
4970   Preamble += "(struct objc_super *, struct objc_selector *, ...);\n";
4971   Preamble += "__OBJC_RW_DLLIMPORT struct objc_object* objc_msgSend_stret";
4972   Preamble += "(struct objc_object *, struct objc_selector *, ...);\n";
4973   Preamble += "__OBJC_RW_DLLIMPORT struct objc_object* objc_msgSendSuper_stret";
4974   Preamble += "(struct objc_super *, struct objc_selector *, ...);\n";
4975   Preamble += "__OBJC_RW_DLLIMPORT double objc_msgSend_fpret";
4976   Preamble += "(struct objc_object *, struct objc_selector *, ...);\n";
4977   Preamble += "__OBJC_RW_DLLIMPORT struct objc_object *objc_getClass";
4978   Preamble += "(const char *);\n";
4979   Preamble += "__OBJC_RW_DLLIMPORT struct objc_class *class_getSuperclass";
4980   Preamble += "(struct objc_class *);\n";
4981   Preamble += "__OBJC_RW_DLLIMPORT struct objc_object *objc_getMetaClass";
4982   Preamble += "(const char *);\n";
4983   Preamble += "__OBJC_RW_DLLIMPORT void objc_exception_throw(struct objc_object *);\n";
4984   Preamble += "__OBJC_RW_DLLIMPORT void objc_exception_try_enter(void *);\n";
4985   Preamble += "__OBJC_RW_DLLIMPORT void objc_exception_try_exit(void *);\n";
4986   Preamble += "__OBJC_RW_DLLIMPORT struct objc_object *objc_exception_extract(void *);\n";
4987   Preamble += "__OBJC_RW_DLLIMPORT int objc_exception_match";
4988   Preamble += "(struct objc_class *, struct objc_object *);\n";
4989   // @synchronized hooks.
4990   Preamble += "__OBJC_RW_DLLIMPORT int objc_sync_enter(struct objc_object *);\n";
4991   Preamble += "__OBJC_RW_DLLIMPORT int objc_sync_exit(struct objc_object *);\n";
4992   Preamble += "__OBJC_RW_DLLIMPORT Protocol *objc_getProtocol(const char *);\n";
4993   Preamble += "#ifndef __FASTENUMERATIONSTATE\n";
4994   Preamble += "struct __objcFastEnumerationState {\n\t";
4995   Preamble += "unsigned long state;\n\t";
4996   Preamble += "void **itemsPtr;\n\t";
4997   Preamble += "unsigned long *mutationsPtr;\n\t";
4998   Preamble += "unsigned long extra[5];\n};\n";
4999   Preamble += "__OBJC_RW_DLLIMPORT void objc_enumerationMutation(struct objc_object *);\n";
5000   Preamble += "#define __FASTENUMERATIONSTATE\n";
5001   Preamble += "#endif\n";
5002   Preamble += "#ifndef __NSCONSTANTSTRINGIMPL\n";
5003   Preamble += "struct __NSConstantStringImpl {\n";
5004   Preamble += "  int *isa;\n";
5005   Preamble += "  int flags;\n";
5006   Preamble += "  char *str;\n";
5007   Preamble += "  long length;\n";
5008   Preamble += "};\n";
5009   Preamble += "#ifdef CF_EXPORT_CONSTANT_STRING\n";
5010   Preamble += "extern \"C\" __declspec(dllexport) int __CFConstantStringClassReference[];\n";
5011   Preamble += "#else\n";
5012   Preamble += "__OBJC_RW_DLLIMPORT int __CFConstantStringClassReference[];\n";
5013   Preamble += "#endif\n";
5014   Preamble += "#define __NSCONSTANTSTRINGIMPL\n";
5015   Preamble += "#endif\n";
5016   // Blocks preamble.
5017   Preamble += "#ifndef BLOCK_IMPL\n";
5018   Preamble += "#define BLOCK_IMPL\n";
5019   Preamble += "struct __block_impl {\n";
5020   Preamble += "  void *isa;\n";
5021   Preamble += "  int Flags;\n";
5022   Preamble += "  int Reserved;\n";
5023   Preamble += "  void *FuncPtr;\n";
5024   Preamble += "};\n";
5025   Preamble += "// Runtime copy/destroy helper functions (from Block_private.h)\n";
5026   Preamble += "#ifdef __OBJC_EXPORT_BLOCKS\n";
5027   Preamble += "extern \"C\" __declspec(dllexport) "
5028   "void _Block_object_assign(void *, const void *, const int);\n";
5029   Preamble += "extern \"C\" __declspec(dllexport) void _Block_object_dispose(const void *, const int);\n";
5030   Preamble += "extern \"C\" __declspec(dllexport) void *_NSConcreteGlobalBlock[32];\n";
5031   Preamble += "extern \"C\" __declspec(dllexport) void *_NSConcreteStackBlock[32];\n";
5032   Preamble += "#else\n";
5033   Preamble += "__OBJC_RW_DLLIMPORT void _Block_object_assign(void *, const void *, const int);\n";
5034   Preamble += "__OBJC_RW_DLLIMPORT void _Block_object_dispose(const void *, const int);\n";
5035   Preamble += "__OBJC_RW_DLLIMPORT void *_NSConcreteGlobalBlock[32];\n";
5036   Preamble += "__OBJC_RW_DLLIMPORT void *_NSConcreteStackBlock[32];\n";
5037   Preamble += "#endif\n";
5038   Preamble += "#endif\n";
5039   if (LangOpts.MicrosoftExt) {
5040     Preamble += "#undef __OBJC_RW_DLLIMPORT\n";
5041     Preamble += "#undef __OBJC_RW_STATICIMPORT\n";
5042     Preamble += "#ifndef KEEP_ATTRIBUTES\n";  // We use this for clang tests.
5043     Preamble += "#define __attribute__(X)\n";
5044     Preamble += "#endif\n";
5045     Preamble += "#define __weak\n";
5046   }
5047   else {
5048     Preamble += "#define __block\n";
5049     Preamble += "#define __weak\n";
5050   }
5051   // NOTE! Windows uses LLP64 for 64bit mode. So, cast pointer to long long
5052   // as this avoids warning in any 64bit/32bit compilation model.
5053   Preamble += "\n#define __OFFSETOFIVAR__(TYPE, MEMBER) ((long long) &((TYPE *)0)->MEMBER)\n";
5054 }
5055 
5056 /// RewriteIvarOffsetComputation - This routine synthesizes computation of
5057 /// ivar offset.
5058 void RewriteObjCFragileABI::RewriteIvarOffsetComputation(ObjCIvarDecl *ivar,
5059                                                          std::string &Result) {
5060   if (ivar->isBitField()) {
5061     // FIXME: The hack below doesn't work for bitfields. For now, we simply
5062     // place all bitfields at offset 0.
5063     Result += "0";
5064   } else {
5065     Result += "__OFFSETOFIVAR__(struct ";
5066     Result += ivar->getContainingInterface()->getNameAsString();
5067     if (LangOpts.MicrosoftExt)
5068       Result += "_IMPL";
5069     Result += ", ";
5070     Result += ivar->getNameAsString();
5071     Result += ")";
5072   }
5073 }
5074 
5075 /// RewriteObjCProtocolMetaData - Rewrite protocols meta-data.
5076 void RewriteObjCFragileABI::RewriteObjCProtocolMetaData(
5077                             ObjCProtocolDecl *PDecl, StringRef prefix,
5078                             StringRef ClassName, std::string &Result) {
5079   static bool objc_protocol_methods = false;
5080 
5081   // Output struct protocol_methods holder of method selector and type.
5082   if (!objc_protocol_methods && PDecl->hasDefinition()) {
5083     /* struct protocol_methods {
5084      SEL _cmd;
5085      char *method_types;
5086      }
5087      */
5088     Result += "\nstruct _protocol_methods {\n";
5089     Result += "\tstruct objc_selector *_cmd;\n";
5090     Result += "\tchar *method_types;\n";
5091     Result += "};\n";
5092 
5093     objc_protocol_methods = true;
5094   }
5095   // Do not synthesize the protocol more than once.
5096   if (ObjCSynthesizedProtocols.count(PDecl->getCanonicalDecl()))
5097     return;
5098 
5099   if (ObjCProtocolDecl *Def = PDecl->getDefinition())
5100     PDecl = Def;
5101 
5102   if (PDecl->instmeth_begin() != PDecl->instmeth_end()) {
5103     unsigned NumMethods = std::distance(PDecl->instmeth_begin(),
5104                                         PDecl->instmeth_end());
5105     /* struct _objc_protocol_method_list {
5106      int protocol_method_count;
5107      struct protocol_methods protocols[];
5108      }
5109      */
5110     Result += "\nstatic struct {\n";
5111     Result += "\tint protocol_method_count;\n";
5112     Result += "\tstruct _protocol_methods protocol_methods[";
5113     Result += utostr(NumMethods);
5114     Result += "];\n} _OBJC_PROTOCOL_INSTANCE_METHODS_";
5115     Result += PDecl->getNameAsString();
5116     Result += " __attribute__ ((used, section (\"__OBJC, __cat_inst_meth\")))= "
5117     "{\n\t" + utostr(NumMethods) + "\n";
5118 
5119     // Output instance methods declared in this protocol.
5120     for (ObjCProtocolDecl::instmeth_iterator
5121          I = PDecl->instmeth_begin(), E = PDecl->instmeth_end();
5122          I != E; ++I) {
5123       if (I == PDecl->instmeth_begin())
5124         Result += "\t  ,{{(struct objc_selector *)\"";
5125       else
5126         Result += "\t  ,{(struct objc_selector *)\"";
5127       Result += (*I)->getSelector().getAsString();
5128       std::string MethodTypeString = Context->getObjCEncodingForMethodDecl(*I);
5129       Result += "\", \"";
5130       Result += MethodTypeString;
5131       Result += "\"}\n";
5132     }
5133     Result += "\t }\n};\n";
5134   }
5135 
5136   // Output class methods declared in this protocol.
5137   unsigned NumMethods = std::distance(PDecl->classmeth_begin(),
5138                                       PDecl->classmeth_end());
5139   if (NumMethods > 0) {
5140     /* struct _objc_protocol_method_list {
5141      int protocol_method_count;
5142      struct protocol_methods protocols[];
5143      }
5144      */
5145     Result += "\nstatic struct {\n";
5146     Result += "\tint protocol_method_count;\n";
5147     Result += "\tstruct _protocol_methods protocol_methods[";
5148     Result += utostr(NumMethods);
5149     Result += "];\n} _OBJC_PROTOCOL_CLASS_METHODS_";
5150     Result += PDecl->getNameAsString();
5151     Result += " __attribute__ ((used, section (\"__OBJC, __cat_cls_meth\")))= "
5152     "{\n\t";
5153     Result += utostr(NumMethods);
5154     Result += "\n";
5155 
5156     // Output instance methods declared in this protocol.
5157     for (ObjCProtocolDecl::classmeth_iterator
5158          I = PDecl->classmeth_begin(), E = PDecl->classmeth_end();
5159          I != E; ++I) {
5160       if (I == PDecl->classmeth_begin())
5161         Result += "\t  ,{{(struct objc_selector *)\"";
5162       else
5163         Result += "\t  ,{(struct objc_selector *)\"";
5164       Result += (*I)->getSelector().getAsString();
5165       std::string MethodTypeString = Context->getObjCEncodingForMethodDecl(*I);
5166       Result += "\", \"";
5167       Result += MethodTypeString;
5168       Result += "\"}\n";
5169     }
5170     Result += "\t }\n};\n";
5171   }
5172 
5173   // Output:
5174   /* struct _objc_protocol {
5175    // Objective-C 1.0 extensions
5176    struct _objc_protocol_extension *isa;
5177    char *protocol_name;
5178    struct _objc_protocol **protocol_list;
5179    struct _objc_protocol_method_list *instance_methods;
5180    struct _objc_protocol_method_list *class_methods;
5181    };
5182    */
5183   static bool objc_protocol = false;
5184   if (!objc_protocol) {
5185     Result += "\nstruct _objc_protocol {\n";
5186     Result += "\tstruct _objc_protocol_extension *isa;\n";
5187     Result += "\tchar *protocol_name;\n";
5188     Result += "\tstruct _objc_protocol **protocol_list;\n";
5189     Result += "\tstruct _objc_protocol_method_list *instance_methods;\n";
5190     Result += "\tstruct _objc_protocol_method_list *class_methods;\n";
5191     Result += "};\n";
5192 
5193     objc_protocol = true;
5194   }
5195 
5196   Result += "\nstatic struct _objc_protocol _OBJC_PROTOCOL_";
5197   Result += PDecl->getNameAsString();
5198   Result += " __attribute__ ((used, section (\"__OBJC, __protocol\")))= "
5199   "{\n\t0, \"";
5200   Result += PDecl->getNameAsString();
5201   Result += "\", 0, ";
5202   if (PDecl->instmeth_begin() != PDecl->instmeth_end()) {
5203     Result += "(struct _objc_protocol_method_list *)&_OBJC_PROTOCOL_INSTANCE_METHODS_";
5204     Result += PDecl->getNameAsString();
5205     Result += ", ";
5206   }
5207   else
5208     Result += "0, ";
5209   if (PDecl->classmeth_begin() != PDecl->classmeth_end()) {
5210     Result += "(struct _objc_protocol_method_list *)&_OBJC_PROTOCOL_CLASS_METHODS_";
5211     Result += PDecl->getNameAsString();
5212     Result += "\n";
5213   }
5214   else
5215     Result += "0\n";
5216   Result += "};\n";
5217 
5218   // Mark this protocol as having been generated.
5219   if (!ObjCSynthesizedProtocols.insert(PDecl->getCanonicalDecl()).second)
5220     llvm_unreachable("protocol already synthesized");
5221 }
5222 
5223 void RewriteObjCFragileABI::RewriteObjCProtocolListMetaData(
5224                                 const ObjCList<ObjCProtocolDecl> &Protocols,
5225                                 StringRef prefix, StringRef ClassName,
5226                                 std::string &Result) {
5227   if (Protocols.empty()) return;
5228 
5229   for (unsigned i = 0; i != Protocols.size(); i++)
5230     RewriteObjCProtocolMetaData(Protocols[i], prefix, ClassName, Result);
5231 
5232   // Output the top lovel protocol meta-data for the class.
5233   /* struct _objc_protocol_list {
5234    struct _objc_protocol_list *next;
5235    int    protocol_count;
5236    struct _objc_protocol *class_protocols[];
5237    }
5238    */
5239   Result += "\nstatic struct {\n";
5240   Result += "\tstruct _objc_protocol_list *next;\n";
5241   Result += "\tint    protocol_count;\n";
5242   Result += "\tstruct _objc_protocol *class_protocols[";
5243   Result += utostr(Protocols.size());
5244   Result += "];\n} _OBJC_";
5245   Result += prefix;
5246   Result += "_PROTOCOLS_";
5247   Result += ClassName;
5248   Result += " __attribute__ ((used, section (\"__OBJC, __cat_cls_meth\")))= "
5249   "{\n\t0, ";
5250   Result += utostr(Protocols.size());
5251   Result += "\n";
5252 
5253   Result += "\t,{&_OBJC_PROTOCOL_";
5254   Result += Protocols[0]->getNameAsString();
5255   Result += " \n";
5256 
5257   for (unsigned i = 1; i != Protocols.size(); i++) {
5258     Result += "\t ,&_OBJC_PROTOCOL_";
5259     Result += Protocols[i]->getNameAsString();
5260     Result += "\n";
5261   }
5262   Result += "\t }\n};\n";
5263 }
5264 
5265 void RewriteObjCFragileABI::RewriteObjCClassMetaData(ObjCImplementationDecl *IDecl,
5266                                            std::string &Result) {
5267   ObjCInterfaceDecl *CDecl = IDecl->getClassInterface();
5268 
5269   // Explicitly declared @interface's are already synthesized.
5270   if (CDecl->isImplicitInterfaceDecl()) {
5271     // FIXME: Implementation of a class with no @interface (legacy) does not
5272     // produce correct synthesis as yet.
5273     RewriteObjCInternalStruct(CDecl, Result);
5274   }
5275 
5276   // Build _objc_ivar_list metadata for classes ivars if needed
5277   unsigned NumIvars = !IDecl->ivar_empty()
5278   ? IDecl->ivar_size()
5279   : (CDecl ? CDecl->ivar_size() : 0);
5280   if (NumIvars > 0) {
5281     static bool objc_ivar = false;
5282     if (!objc_ivar) {
5283       /* struct _objc_ivar {
5284        char *ivar_name;
5285        char *ivar_type;
5286        int ivar_offset;
5287        };
5288        */
5289       Result += "\nstruct _objc_ivar {\n";
5290       Result += "\tchar *ivar_name;\n";
5291       Result += "\tchar *ivar_type;\n";
5292       Result += "\tint ivar_offset;\n";
5293       Result += "};\n";
5294 
5295       objc_ivar = true;
5296     }
5297 
5298     /* struct {
5299      int ivar_count;
5300      struct _objc_ivar ivar_list[nIvars];
5301      };
5302      */
5303     Result += "\nstatic struct {\n";
5304     Result += "\tint ivar_count;\n";
5305     Result += "\tstruct _objc_ivar ivar_list[";
5306     Result += utostr(NumIvars);
5307     Result += "];\n} _OBJC_INSTANCE_VARIABLES_";
5308     Result += IDecl->getNameAsString();
5309     Result += " __attribute__ ((used, section (\"__OBJC, __instance_vars\")))= "
5310     "{\n\t";
5311     Result += utostr(NumIvars);
5312     Result += "\n";
5313 
5314     ObjCInterfaceDecl::ivar_iterator IVI, IVE;
5315     SmallVector<ObjCIvarDecl *, 8> IVars;
5316     if (!IDecl->ivar_empty()) {
5317       for (auto *IV : IDecl->ivars())
5318         IVars.push_back(IV);
5319       IVI = IDecl->ivar_begin();
5320       IVE = IDecl->ivar_end();
5321     } else {
5322       IVI = CDecl->ivar_begin();
5323       IVE = CDecl->ivar_end();
5324     }
5325     Result += "\t,{{\"";
5326     Result += IVI->getNameAsString();
5327     Result += "\", \"";
5328     std::string TmpString, StrEncoding;
5329     Context->getObjCEncodingForType(IVI->getType(), TmpString, *IVI);
5330     QuoteDoublequotes(TmpString, StrEncoding);
5331     Result += StrEncoding;
5332     Result += "\", ";
5333     RewriteIvarOffsetComputation(*IVI, Result);
5334     Result += "}\n";
5335     for (++IVI; IVI != IVE; ++IVI) {
5336       Result += "\t  ,{\"";
5337       Result += IVI->getNameAsString();
5338       Result += "\", \"";
5339       std::string TmpString, StrEncoding;
5340       Context->getObjCEncodingForType(IVI->getType(), TmpString, *IVI);
5341       QuoteDoublequotes(TmpString, StrEncoding);
5342       Result += StrEncoding;
5343       Result += "\", ";
5344       RewriteIvarOffsetComputation(*IVI, Result);
5345       Result += "}\n";
5346     }
5347 
5348     Result += "\t }\n};\n";
5349   }
5350 
5351   // Build _objc_method_list for class's instance methods if needed
5352   SmallVector<ObjCMethodDecl *, 32> InstanceMethods(IDecl->instance_methods());
5353 
5354   // If any of our property implementations have associated getters or
5355   // setters, produce metadata for them as well.
5356   for (const auto *Prop : IDecl->property_impls()) {
5357     if (Prop->getPropertyImplementation() == ObjCPropertyImplDecl::Dynamic)
5358       continue;
5359     if (!Prop->getPropertyIvarDecl())
5360       continue;
5361     ObjCPropertyDecl *PD = Prop->getPropertyDecl();
5362     if (!PD)
5363       continue;
5364     if (ObjCMethodDecl *Getter = Prop->getGetterMethodDecl())
5365       if (!Getter->isDefined())
5366         InstanceMethods.push_back(Getter);
5367     if (PD->isReadOnly())
5368       continue;
5369     if (ObjCMethodDecl *Setter = Prop->getSetterMethodDecl())
5370       if (!Setter->isDefined())
5371         InstanceMethods.push_back(Setter);
5372   }
5373   RewriteObjCMethodsMetaData(InstanceMethods.begin(), InstanceMethods.end(),
5374                              true, "", IDecl->getName(), Result);
5375 
5376   // Build _objc_method_list for class's class methods if needed
5377   RewriteObjCMethodsMetaData(IDecl->classmeth_begin(), IDecl->classmeth_end(),
5378                              false, "", IDecl->getName(), Result);
5379 
5380   // Protocols referenced in class declaration?
5381   RewriteObjCProtocolListMetaData(CDecl->getReferencedProtocols(),
5382                                   "CLASS", CDecl->getName(), Result);
5383 
5384   // Declaration of class/meta-class metadata
5385   /* struct _objc_class {
5386    struct _objc_class *isa; // or const char *root_class_name when metadata
5387    const char *super_class_name;
5388    char *name;
5389    long version;
5390    long info;
5391    long instance_size;
5392    struct _objc_ivar_list *ivars;
5393    struct _objc_method_list *methods;
5394    struct objc_cache *cache;
5395    struct objc_protocol_list *protocols;
5396    const char *ivar_layout;
5397    struct _objc_class_ext  *ext;
5398    };
5399    */
5400   static bool objc_class = false;
5401   if (!objc_class) {
5402     Result += "\nstruct _objc_class {\n";
5403     Result += "\tstruct _objc_class *isa;\n";
5404     Result += "\tconst char *super_class_name;\n";
5405     Result += "\tchar *name;\n";
5406     Result += "\tlong version;\n";
5407     Result += "\tlong info;\n";
5408     Result += "\tlong instance_size;\n";
5409     Result += "\tstruct _objc_ivar_list *ivars;\n";
5410     Result += "\tstruct _objc_method_list *methods;\n";
5411     Result += "\tstruct objc_cache *cache;\n";
5412     Result += "\tstruct _objc_protocol_list *protocols;\n";
5413     Result += "\tconst char *ivar_layout;\n";
5414     Result += "\tstruct _objc_class_ext  *ext;\n";
5415     Result += "};\n";
5416     objc_class = true;
5417   }
5418 
5419   // Meta-class metadata generation.
5420   ObjCInterfaceDecl *RootClass = nullptr;
5421   ObjCInterfaceDecl *SuperClass = CDecl->getSuperClass();
5422   while (SuperClass) {
5423     RootClass = SuperClass;
5424     SuperClass = SuperClass->getSuperClass();
5425   }
5426   SuperClass = CDecl->getSuperClass();
5427 
5428   Result += "\nstatic struct _objc_class _OBJC_METACLASS_";
5429   Result += CDecl->getNameAsString();
5430   Result += " __attribute__ ((used, section (\"__OBJC, __meta_class\")))= "
5431   "{\n\t(struct _objc_class *)\"";
5432   Result += (RootClass ? RootClass->getNameAsString() : CDecl->getNameAsString());
5433   Result += "\"";
5434 
5435   if (SuperClass) {
5436     Result += ", \"";
5437     Result += SuperClass->getNameAsString();
5438     Result += "\", \"";
5439     Result += CDecl->getNameAsString();
5440     Result += "\"";
5441   }
5442   else {
5443     Result += ", 0, \"";
5444     Result += CDecl->getNameAsString();
5445     Result += "\"";
5446   }
5447   // Set 'ivars' field for root class to 0. ObjC1 runtime does not use it.
5448   // 'info' field is initialized to CLS_META(2) for metaclass
5449   Result += ", 0,2, sizeof(struct _objc_class), 0";
5450   if (IDecl->classmeth_begin() != IDecl->classmeth_end()) {
5451     Result += "\n\t, (struct _objc_method_list *)&_OBJC_CLASS_METHODS_";
5452     Result += IDecl->getNameAsString();
5453     Result += "\n";
5454   }
5455   else
5456     Result += ", 0\n";
5457   if (CDecl->protocol_begin() != CDecl->protocol_end()) {
5458     Result += "\t,0, (struct _objc_protocol_list *)&_OBJC_CLASS_PROTOCOLS_";
5459     Result += CDecl->getNameAsString();
5460     Result += ",0,0\n";
5461   }
5462   else
5463     Result += "\t,0,0,0,0\n";
5464   Result += "};\n";
5465 
5466   // class metadata generation.
5467   Result += "\nstatic struct _objc_class _OBJC_CLASS_";
5468   Result += CDecl->getNameAsString();
5469   Result += " __attribute__ ((used, section (\"__OBJC, __class\")))= "
5470   "{\n\t&_OBJC_METACLASS_";
5471   Result += CDecl->getNameAsString();
5472   if (SuperClass) {
5473     Result += ", \"";
5474     Result += SuperClass->getNameAsString();
5475     Result += "\", \"";
5476     Result += CDecl->getNameAsString();
5477     Result += "\"";
5478   }
5479   else {
5480     Result += ", 0, \"";
5481     Result += CDecl->getNameAsString();
5482     Result += "\"";
5483   }
5484   // 'info' field is initialized to CLS_CLASS(1) for class
5485   Result += ", 0,1";
5486   if (!ObjCSynthesizedStructs.count(CDecl))
5487     Result += ",0";
5488   else {
5489     // class has size. Must synthesize its size.
5490     Result += ",sizeof(struct ";
5491     Result += CDecl->getNameAsString();
5492     if (LangOpts.MicrosoftExt)
5493       Result += "_IMPL";
5494     Result += ")";
5495   }
5496   if (NumIvars > 0) {
5497     Result += ", (struct _objc_ivar_list *)&_OBJC_INSTANCE_VARIABLES_";
5498     Result += CDecl->getNameAsString();
5499     Result += "\n\t";
5500   }
5501   else
5502     Result += ",0";
5503   if (IDecl->instmeth_begin() != IDecl->instmeth_end()) {
5504     Result += ", (struct _objc_method_list *)&_OBJC_INSTANCE_METHODS_";
5505     Result += CDecl->getNameAsString();
5506     Result += ", 0\n\t";
5507   }
5508   else
5509     Result += ",0,0";
5510   if (CDecl->protocol_begin() != CDecl->protocol_end()) {
5511     Result += ", (struct _objc_protocol_list*)&_OBJC_CLASS_PROTOCOLS_";
5512     Result += CDecl->getNameAsString();
5513     Result += ", 0,0\n";
5514   }
5515   else
5516     Result += ",0,0,0\n";
5517   Result += "};\n";
5518 }
5519 
5520 void RewriteObjCFragileABI::RewriteMetaDataIntoBuffer(std::string &Result) {
5521   int ClsDefCount = ClassImplementation.size();
5522   int CatDefCount = CategoryImplementation.size();
5523 
5524   // For each implemented class, write out all its meta data.
5525   for (int i = 0; i < ClsDefCount; i++)
5526     RewriteObjCClassMetaData(ClassImplementation[i], Result);
5527 
5528   // For each implemented category, write out all its meta data.
5529   for (int i = 0; i < CatDefCount; i++)
5530     RewriteObjCCategoryImplDecl(CategoryImplementation[i], Result);
5531 
5532   // Write objc_symtab metadata
5533   /*
5534    struct _objc_symtab
5535    {
5536    long sel_ref_cnt;
5537    SEL *refs;
5538    short cls_def_cnt;
5539    short cat_def_cnt;
5540    void *defs[cls_def_cnt + cat_def_cnt];
5541    };
5542    */
5543 
5544   Result += "\nstruct _objc_symtab {\n";
5545   Result += "\tlong sel_ref_cnt;\n";
5546   Result += "\tSEL *refs;\n";
5547   Result += "\tshort cls_def_cnt;\n";
5548   Result += "\tshort cat_def_cnt;\n";
5549   Result += "\tvoid *defs[" + utostr(ClsDefCount + CatDefCount)+ "];\n";
5550   Result += "};\n\n";
5551 
5552   Result += "static struct _objc_symtab "
5553   "_OBJC_SYMBOLS __attribute__((used, section (\"__OBJC, __symbols\")))= {\n";
5554   Result += "\t0, 0, " + utostr(ClsDefCount)
5555   + ", " + utostr(CatDefCount) + "\n";
5556   for (int i = 0; i < ClsDefCount; i++) {
5557     Result += "\t,&_OBJC_CLASS_";
5558     Result += ClassImplementation[i]->getNameAsString();
5559     Result += "\n";
5560   }
5561 
5562   for (int i = 0; i < CatDefCount; i++) {
5563     Result += "\t,&_OBJC_CATEGORY_";
5564     Result += CategoryImplementation[i]->getClassInterface()->getNameAsString();
5565     Result += "_";
5566     Result += CategoryImplementation[i]->getNameAsString();
5567     Result += "\n";
5568   }
5569 
5570   Result += "};\n\n";
5571 
5572   // Write objc_module metadata
5573 
5574   /*
5575    struct _objc_module {
5576    long version;
5577    long size;
5578    const char *name;
5579    struct _objc_symtab *symtab;
5580    }
5581    */
5582 
5583   Result += "\nstruct _objc_module {\n";
5584   Result += "\tlong version;\n";
5585   Result += "\tlong size;\n";
5586   Result += "\tconst char *name;\n";
5587   Result += "\tstruct _objc_symtab *symtab;\n";
5588   Result += "};\n\n";
5589   Result += "static struct _objc_module "
5590   "_OBJC_MODULES __attribute__ ((used, section (\"__OBJC, __module_info\")))= {\n";
5591   Result += "\t" + utostr(OBJC_ABI_VERSION) +
5592   ", sizeof(struct _objc_module), \"\", &_OBJC_SYMBOLS\n";
5593   Result += "};\n\n";
5594 
5595   if (LangOpts.MicrosoftExt) {
5596     if (ProtocolExprDecls.size()) {
5597       Result += "#pragma section(\".objc_protocol$B\",long,read,write)\n";
5598       Result += "#pragma data_seg(push, \".objc_protocol$B\")\n";
5599       for (ObjCProtocolDecl *ProtDecl : ProtocolExprDecls) {
5600         Result += "static struct _objc_protocol *_POINTER_OBJC_PROTOCOL_";
5601         Result += ProtDecl->getNameAsString();
5602         Result += " = &_OBJC_PROTOCOL_";
5603         Result += ProtDecl->getNameAsString();
5604         Result += ";\n";
5605       }
5606       Result += "#pragma data_seg(pop)\n\n";
5607     }
5608     Result += "#pragma section(\".objc_module_info$B\",long,read,write)\n";
5609     Result += "#pragma data_seg(push, \".objc_module_info$B\")\n";
5610     Result += "static struct _objc_module *_POINTER_OBJC_MODULES = ";
5611     Result += "&_OBJC_MODULES;\n";
5612     Result += "#pragma data_seg(pop)\n\n";
5613   }
5614 }
5615 
5616 /// RewriteObjCCategoryImplDecl - Rewrite metadata for each category
5617 /// implementation.
5618 void RewriteObjCFragileABI::RewriteObjCCategoryImplDecl(ObjCCategoryImplDecl *IDecl,
5619                                               std::string &Result) {
5620   ObjCInterfaceDecl *ClassDecl = IDecl->getClassInterface();
5621   // Find category declaration for this implementation.
5622   ObjCCategoryDecl *CDecl
5623     = ClassDecl->FindCategoryDeclaration(IDecl->getIdentifier());
5624 
5625   std::string FullCategoryName = ClassDecl->getNameAsString();
5626   FullCategoryName += '_';
5627   FullCategoryName += IDecl->getNameAsString();
5628 
5629   // Build _objc_method_list for class's instance methods if needed
5630   SmallVector<ObjCMethodDecl *, 32> InstanceMethods(IDecl->instance_methods());
5631 
5632   // If any of our property implementations have associated getters or
5633   // setters, produce metadata for them as well.
5634   for (const auto *Prop : IDecl->property_impls()) {
5635     if (Prop->getPropertyImplementation() == ObjCPropertyImplDecl::Dynamic)
5636       continue;
5637     if (!Prop->getPropertyIvarDecl())
5638       continue;
5639     ObjCPropertyDecl *PD = Prop->getPropertyDecl();
5640     if (!PD)
5641       continue;
5642     if (ObjCMethodDecl *Getter = Prop->getGetterMethodDecl())
5643       InstanceMethods.push_back(Getter);
5644     if (PD->isReadOnly())
5645       continue;
5646     if (ObjCMethodDecl *Setter = Prop->getSetterMethodDecl())
5647       InstanceMethods.push_back(Setter);
5648   }
5649   RewriteObjCMethodsMetaData(InstanceMethods.begin(), InstanceMethods.end(),
5650                              true, "CATEGORY_", FullCategoryName, Result);
5651 
5652   // Build _objc_method_list for class's class methods if needed
5653   RewriteObjCMethodsMetaData(IDecl->classmeth_begin(), IDecl->classmeth_end(),
5654                              false, "CATEGORY_", FullCategoryName, Result);
5655 
5656   // Protocols referenced in class declaration?
5657   // Null CDecl is case of a category implementation with no category interface
5658   if (CDecl)
5659     RewriteObjCProtocolListMetaData(CDecl->getReferencedProtocols(), "CATEGORY",
5660                                     FullCategoryName, Result);
5661   /* struct _objc_category {
5662    char *category_name;
5663    char *class_name;
5664    struct _objc_method_list *instance_methods;
5665    struct _objc_method_list *class_methods;
5666    struct _objc_protocol_list *protocols;
5667    // Objective-C 1.0 extensions
5668    uint32_t size;     // sizeof (struct _objc_category)
5669    struct _objc_property_list *instance_properties;  // category's own
5670    // @property decl.
5671    };
5672    */
5673 
5674   static bool objc_category = false;
5675   if (!objc_category) {
5676     Result += "\nstruct _objc_category {\n";
5677     Result += "\tchar *category_name;\n";
5678     Result += "\tchar *class_name;\n";
5679     Result += "\tstruct _objc_method_list *instance_methods;\n";
5680     Result += "\tstruct _objc_method_list *class_methods;\n";
5681     Result += "\tstruct _objc_protocol_list *protocols;\n";
5682     Result += "\tunsigned int size;\n";
5683     Result += "\tstruct _objc_property_list *instance_properties;\n";
5684     Result += "};\n";
5685     objc_category = true;
5686   }
5687   Result += "\nstatic struct _objc_category _OBJC_CATEGORY_";
5688   Result += FullCategoryName;
5689   Result += " __attribute__ ((used, section (\"__OBJC, __category\")))= {\n\t\"";
5690   Result += IDecl->getNameAsString();
5691   Result += "\"\n\t, \"";
5692   Result += ClassDecl->getNameAsString();
5693   Result += "\"\n";
5694 
5695   if (IDecl->instmeth_begin() != IDecl->instmeth_end()) {
5696     Result += "\t, (struct _objc_method_list *)"
5697     "&_OBJC_CATEGORY_INSTANCE_METHODS_";
5698     Result += FullCategoryName;
5699     Result += "\n";
5700   }
5701   else
5702     Result += "\t, 0\n";
5703   if (IDecl->classmeth_begin() != IDecl->classmeth_end()) {
5704     Result += "\t, (struct _objc_method_list *)"
5705     "&_OBJC_CATEGORY_CLASS_METHODS_";
5706     Result += FullCategoryName;
5707     Result += "\n";
5708   }
5709   else
5710     Result += "\t, 0\n";
5711 
5712   if (CDecl && CDecl->protocol_begin() != CDecl->protocol_end()) {
5713     Result += "\t, (struct _objc_protocol_list *)&_OBJC_CATEGORY_PROTOCOLS_";
5714     Result += FullCategoryName;
5715     Result += "\n";
5716   }
5717   else
5718     Result += "\t, 0\n";
5719   Result += "\t, sizeof(struct _objc_category), 0\n};\n";
5720 }
5721 
5722 // RewriteObjCMethodsMetaData - Rewrite methods metadata for instance or
5723 /// class methods.
5724 template<typename MethodIterator>
5725 void RewriteObjCFragileABI::RewriteObjCMethodsMetaData(MethodIterator MethodBegin,
5726                                              MethodIterator MethodEnd,
5727                                              bool IsInstanceMethod,
5728                                              StringRef prefix,
5729                                              StringRef ClassName,
5730                                              std::string &Result) {
5731   if (MethodBegin == MethodEnd) return;
5732 
5733   if (!objc_impl_method) {
5734     /* struct _objc_method {
5735      SEL _cmd;
5736      char *method_types;
5737      void *_imp;
5738      }
5739      */
5740     Result += "\nstruct _objc_method {\n";
5741     Result += "\tSEL _cmd;\n";
5742     Result += "\tchar *method_types;\n";
5743     Result += "\tvoid *_imp;\n";
5744     Result += "};\n";
5745 
5746     objc_impl_method = true;
5747   }
5748 
5749   // Build _objc_method_list for class's methods if needed
5750 
5751   /* struct  {
5752    struct _objc_method_list *next_method;
5753    int method_count;
5754    struct _objc_method method_list[];
5755    }
5756    */
5757   unsigned NumMethods = std::distance(MethodBegin, MethodEnd);
5758   Result += "\nstatic struct {\n";
5759   Result += "\tstruct _objc_method_list *next_method;\n";
5760   Result += "\tint method_count;\n";
5761   Result += "\tstruct _objc_method method_list[";
5762   Result += utostr(NumMethods);
5763   Result += "];\n} _OBJC_";
5764   Result += prefix;
5765   Result += IsInstanceMethod ? "INSTANCE" : "CLASS";
5766   Result += "_METHODS_";
5767   Result += ClassName;
5768   Result += " __attribute__ ((used, section (\"__OBJC, __";
5769   Result += IsInstanceMethod ? "inst" : "cls";
5770   Result += "_meth\")))= ";
5771   Result += "{\n\t0, " + utostr(NumMethods) + "\n";
5772 
5773   Result += "\t,{{(SEL)\"";
5774   Result += (*MethodBegin)->getSelector().getAsString();
5775   std::string MethodTypeString =
5776     Context->getObjCEncodingForMethodDecl(*MethodBegin);
5777   Result += "\", \"";
5778   Result += MethodTypeString;
5779   Result += "\", (void *)";
5780   Result += MethodInternalNames[*MethodBegin];
5781   Result += "}\n";
5782   for (++MethodBegin; MethodBegin != MethodEnd; ++MethodBegin) {
5783     Result += "\t  ,{(SEL)\"";
5784     Result += (*MethodBegin)->getSelector().getAsString();
5785     std::string MethodTypeString =
5786       Context->getObjCEncodingForMethodDecl(*MethodBegin);
5787     Result += "\", \"";
5788     Result += MethodTypeString;
5789     Result += "\", (void *)";
5790     Result += MethodInternalNames[*MethodBegin];
5791     Result += "}\n";
5792   }
5793   Result += "\t }\n};\n";
5794 }
5795 
5796 Stmt *RewriteObjCFragileABI::RewriteObjCIvarRefExpr(ObjCIvarRefExpr *IV) {
5797   SourceRange OldRange = IV->getSourceRange();
5798   Expr *BaseExpr = IV->getBase();
5799 
5800   // Rewrite the base, but without actually doing replaces.
5801   {
5802     DisableReplaceStmtScope S(*this);
5803     BaseExpr = cast<Expr>(RewriteFunctionBodyOrGlobalInitializer(BaseExpr));
5804     IV->setBase(BaseExpr);
5805   }
5806 
5807   ObjCIvarDecl *D = IV->getDecl();
5808 
5809   Expr *Replacement = IV;
5810   if (CurMethodDef) {
5811     if (BaseExpr->getType()->isObjCObjectPointerType()) {
5812       const ObjCInterfaceType *iFaceDecl =
5813       dyn_cast<ObjCInterfaceType>(BaseExpr->getType()->getPointeeType());
5814       assert(iFaceDecl && "RewriteObjCIvarRefExpr - iFaceDecl is null");
5815       // lookup which class implements the instance variable.
5816       ObjCInterfaceDecl *clsDeclared = nullptr;
5817       iFaceDecl->getDecl()->lookupInstanceVariable(D->getIdentifier(),
5818                                                    clsDeclared);
5819       assert(clsDeclared && "RewriteObjCIvarRefExpr(): Can't find class");
5820 
5821       // Synthesize an explicit cast to gain access to the ivar.
5822       std::string RecName = clsDeclared->getIdentifier()->getName();
5823       RecName += "_IMPL";
5824       IdentifierInfo *II = &Context->Idents.get(RecName);
5825       RecordDecl *RD = RecordDecl::Create(*Context, TTK_Struct, TUDecl,
5826                                           SourceLocation(), SourceLocation(),
5827                                           II);
5828       assert(RD && "RewriteObjCIvarRefExpr(): Can't find RecordDecl");
5829       QualType castT = Context->getPointerType(Context->getTagDeclType(RD));
5830       CastExpr *castExpr = NoTypeInfoCStyleCastExpr(Context, castT,
5831                                                     CK_BitCast,
5832                                                     IV->getBase());
5833       // Don't forget the parens to enforce the proper binding.
5834       ParenExpr *PE = new (Context) ParenExpr(OldRange.getBegin(),
5835                                               OldRange.getEnd(),
5836                                               castExpr);
5837       if (IV->isFreeIvar() &&
5838           declaresSameEntity(CurMethodDef->getClassInterface(),
5839                              iFaceDecl->getDecl())) {
5840         MemberExpr *ME = MemberExpr::CreateImplicit(
5841             *Context, PE, true, D, D->getType(), VK_LValue, OK_Ordinary);
5842         Replacement = ME;
5843       } else {
5844         IV->setBase(PE);
5845       }
5846     }
5847   } else { // we are outside a method.
5848     assert(!IV->isFreeIvar() && "Cannot have a free standing ivar outside a method");
5849 
5850     // Explicit ivar refs need to have a cast inserted.
5851     // FIXME: consider sharing some of this code with the code above.
5852     if (BaseExpr->getType()->isObjCObjectPointerType()) {
5853       const ObjCInterfaceType *iFaceDecl =
5854       dyn_cast<ObjCInterfaceType>(BaseExpr->getType()->getPointeeType());
5855       // lookup which class implements the instance variable.
5856       ObjCInterfaceDecl *clsDeclared = nullptr;
5857       iFaceDecl->getDecl()->lookupInstanceVariable(D->getIdentifier(),
5858                                                    clsDeclared);
5859       assert(clsDeclared && "RewriteObjCIvarRefExpr(): Can't find class");
5860 
5861       // Synthesize an explicit cast to gain access to the ivar.
5862       std::string RecName = clsDeclared->getIdentifier()->getName();
5863       RecName += "_IMPL";
5864       IdentifierInfo *II = &Context->Idents.get(RecName);
5865       RecordDecl *RD = RecordDecl::Create(*Context, TTK_Struct, TUDecl,
5866                                           SourceLocation(), SourceLocation(),
5867                                           II);
5868       assert(RD && "RewriteObjCIvarRefExpr(): Can't find RecordDecl");
5869       QualType castT = Context->getPointerType(Context->getTagDeclType(RD));
5870       CastExpr *castExpr = NoTypeInfoCStyleCastExpr(Context, castT,
5871                                                     CK_BitCast,
5872                                                     IV->getBase());
5873       // Don't forget the parens to enforce the proper binding.
5874       ParenExpr *PE = new (Context) ParenExpr(
5875           IV->getBase()->getBeginLoc(), IV->getBase()->getEndLoc(), castExpr);
5876       // Cannot delete IV->getBase(), since PE points to it.
5877       // Replace the old base with the cast. This is important when doing
5878       // embedded rewrites. For example, [newInv->_container addObject:0].
5879       IV->setBase(PE);
5880     }
5881   }
5882 
5883   ReplaceStmtWithRange(IV, Replacement, OldRange);
5884   return Replacement;
5885 }
5886 
5887 #endif // CLANG_ENABLE_OBJC_REWRITER
5888