clang  3.7.0
CGObjCGNU.cpp
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1 //===------- CGObjCGNU.cpp - Emit LLVM Code from ASTs for a Module --------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This provides Objective-C code generation targeting the GNU runtime. The
11 // class in this file generates structures used by the GNU Objective-C runtime
12 // library. These structures are defined in objc/objc.h and objc/objc-api.h in
13 // the GNU runtime distribution.
14 //
15 //===----------------------------------------------------------------------===//
16 
17 #include "CGObjCRuntime.h"
18 #include "CGCleanup.h"
19 #include "CodeGenFunction.h"
20 #include "CodeGenModule.h"
21 #include "clang/AST/ASTContext.h"
22 #include "clang/AST/Decl.h"
23 #include "clang/AST/DeclObjC.h"
24 #include "clang/AST/RecordLayout.h"
25 #include "clang/AST/StmtObjC.h"
28 #include "llvm/ADT/SmallVector.h"
29 #include "llvm/ADT/StringMap.h"
30 #include "llvm/IR/CallSite.h"
31 #include "llvm/IR/DataLayout.h"
32 #include "llvm/IR/Intrinsics.h"
33 #include "llvm/IR/LLVMContext.h"
34 #include "llvm/IR/Module.h"
35 #include "llvm/Support/Compiler.h"
36 #include <cstdarg>
37 
38 
39 using namespace clang;
40 using namespace CodeGen;
41 
42 
43 namespace {
44 /// Class that lazily initialises the runtime function. Avoids inserting the
45 /// types and the function declaration into a module if they're not used, and
46 /// avoids constructing the type more than once if it's used more than once.
47 class LazyRuntimeFunction {
48  CodeGenModule *CGM;
49  llvm::FunctionType *FTy;
50  const char *FunctionName;
51  llvm::Constant *Function;
52 
53 public:
54  /// Constructor leaves this class uninitialized, because it is intended to
55  /// be used as a field in another class and not all of the types that are
56  /// used as arguments will necessarily be available at construction time.
57  LazyRuntimeFunction()
58  : CGM(nullptr), FunctionName(nullptr), Function(nullptr) {}
59 
60  /// Initialises the lazy function with the name, return type, and the types
61  /// of the arguments.
62  LLVM_END_WITH_NULL
63  void init(CodeGenModule *Mod, const char *name, llvm::Type *RetTy, ...) {
64  CGM = Mod;
65  FunctionName = name;
66  Function = nullptr;
67  std::vector<llvm::Type *> ArgTys;
68  va_list Args;
69  va_start(Args, RetTy);
70  while (llvm::Type *ArgTy = va_arg(Args, llvm::Type *))
71  ArgTys.push_back(ArgTy);
72  va_end(Args);
73  FTy = llvm::FunctionType::get(RetTy, ArgTys, false);
74  }
75 
76  llvm::FunctionType *getType() { return FTy; }
77 
78  /// Overloaded cast operator, allows the class to be implicitly cast to an
79  /// LLVM constant.
80  operator llvm::Constant *() {
81  if (!Function) {
82  if (!FunctionName)
83  return nullptr;
84  Function =
85  cast<llvm::Constant>(CGM->CreateRuntimeFunction(FTy, FunctionName));
86  }
87  return Function;
88  }
89  operator llvm::Function *() {
90  return cast<llvm::Function>((llvm::Constant *)*this);
91  }
92 };
93 
94 
95 /// GNU Objective-C runtime code generation. This class implements the parts of
96 /// Objective-C support that are specific to the GNU family of runtimes (GCC,
97 /// GNUstep and ObjFW).
98 class CGObjCGNU : public CGObjCRuntime {
99 protected:
100  /// The LLVM module into which output is inserted
101  llvm::Module &TheModule;
102  /// strut objc_super. Used for sending messages to super. This structure
103  /// contains the receiver (object) and the expected class.
104  llvm::StructType *ObjCSuperTy;
105  /// struct objc_super*. The type of the argument to the superclass message
106  /// lookup functions.
107  llvm::PointerType *PtrToObjCSuperTy;
108  /// LLVM type for selectors. Opaque pointer (i8*) unless a header declaring
109  /// SEL is included in a header somewhere, in which case it will be whatever
110  /// type is declared in that header, most likely {i8*, i8*}.
111  llvm::PointerType *SelectorTy;
112  /// LLVM i8 type. Cached here to avoid repeatedly getting it in all of the
113  /// places where it's used
114  llvm::IntegerType *Int8Ty;
115  /// Pointer to i8 - LLVM type of char*, for all of the places where the
116  /// runtime needs to deal with C strings.
117  llvm::PointerType *PtrToInt8Ty;
118  /// Instance Method Pointer type. This is a pointer to a function that takes,
119  /// at a minimum, an object and a selector, and is the generic type for
120  /// Objective-C methods. Due to differences between variadic / non-variadic
121  /// calling conventions, it must always be cast to the correct type before
122  /// actually being used.
123  llvm::PointerType *IMPTy;
124  /// Type of an untyped Objective-C object. Clang treats id as a built-in type
125  /// when compiling Objective-C code, so this may be an opaque pointer (i8*),
126  /// but if the runtime header declaring it is included then it may be a
127  /// pointer to a structure.
128  llvm::PointerType *IdTy;
129  /// Pointer to a pointer to an Objective-C object. Used in the new ABI
130  /// message lookup function and some GC-related functions.
131  llvm::PointerType *PtrToIdTy;
132  /// The clang type of id. Used when using the clang CGCall infrastructure to
133  /// call Objective-C methods.
134  CanQualType ASTIdTy;
135  /// LLVM type for C int type.
136  llvm::IntegerType *IntTy;
137  /// LLVM type for an opaque pointer. This is identical to PtrToInt8Ty, but is
138  /// used in the code to document the difference between i8* meaning a pointer
139  /// to a C string and i8* meaning a pointer to some opaque type.
140  llvm::PointerType *PtrTy;
141  /// LLVM type for C long type. The runtime uses this in a lot of places where
142  /// it should be using intptr_t, but we can't fix this without breaking
143  /// compatibility with GCC...
144  llvm::IntegerType *LongTy;
145  /// LLVM type for C size_t. Used in various runtime data structures.
146  llvm::IntegerType *SizeTy;
147  /// LLVM type for C intptr_t.
148  llvm::IntegerType *IntPtrTy;
149  /// LLVM type for C ptrdiff_t. Mainly used in property accessor functions.
150  llvm::IntegerType *PtrDiffTy;
151  /// LLVM type for C int*. Used for GCC-ABI-compatible non-fragile instance
152  /// variables.
153  llvm::PointerType *PtrToIntTy;
154  /// LLVM type for Objective-C BOOL type.
155  llvm::Type *BoolTy;
156  /// 32-bit integer type, to save us needing to look it up every time it's used.
157  llvm::IntegerType *Int32Ty;
158  /// 64-bit integer type, to save us needing to look it up every time it's used.
159  llvm::IntegerType *Int64Ty;
160  /// Metadata kind used to tie method lookups to message sends. The GNUstep
161  /// runtime provides some LLVM passes that can use this to do things like
162  /// automatic IMP caching and speculative inlining.
163  unsigned msgSendMDKind;
164  /// Helper function that generates a constant string and returns a pointer to
165  /// the start of the string. The result of this function can be used anywhere
166  /// where the C code specifies const char*.
167  llvm::Constant *MakeConstantString(const std::string &Str,
168  const std::string &Name="") {
169  auto *ConstStr = CGM.GetAddrOfConstantCString(Str, Name.c_str());
170  return llvm::ConstantExpr::getGetElementPtr(ConstStr->getValueType(),
171  ConstStr, Zeros);
172  }
173  /// Emits a linkonce_odr string, whose name is the prefix followed by the
174  /// string value. This allows the linker to combine the strings between
175  /// different modules. Used for EH typeinfo names, selector strings, and a
176  /// few other things.
177  llvm::Constant *ExportUniqueString(const std::string &Str,
178  const std::string prefix) {
179  std::string name = prefix + Str;
180  auto *ConstStr = TheModule.getGlobalVariable(name);
181  if (!ConstStr) {
182  llvm::Constant *value = llvm::ConstantDataArray::getString(VMContext,Str);
183  ConstStr = new llvm::GlobalVariable(TheModule, value->getType(), true,
184  llvm::GlobalValue::LinkOnceODRLinkage, value, prefix + Str);
185  }
186  return llvm::ConstantExpr::getGetElementPtr(ConstStr->getValueType(),
187  ConstStr, Zeros);
188  }
189  /// Generates a global structure, initialized by the elements in the vector.
190  /// The element types must match the types of the structure elements in the
191  /// first argument.
192  llvm::GlobalVariable *MakeGlobal(llvm::StructType *Ty,
194  StringRef Name="",
195  llvm::GlobalValue::LinkageTypes linkage
197  llvm::Constant *C = llvm::ConstantStruct::get(Ty, V);
198  return new llvm::GlobalVariable(TheModule, Ty, false,
199  linkage, C, Name);
200  }
201  /// Generates a global array. The vector must contain the same number of
202  /// elements that the array type declares, of the type specified as the array
203  /// element type.
204  llvm::GlobalVariable *MakeGlobal(llvm::ArrayType *Ty,
206  StringRef Name="",
207  llvm::GlobalValue::LinkageTypes linkage
209  llvm::Constant *C = llvm::ConstantArray::get(Ty, V);
210  return new llvm::GlobalVariable(TheModule, Ty, false,
211  linkage, C, Name);
212  }
213  /// Generates a global array, inferring the array type from the specified
214  /// element type and the size of the initialiser.
215  llvm::GlobalVariable *MakeGlobalArray(llvm::Type *Ty,
217  StringRef Name="",
218  llvm::GlobalValue::LinkageTypes linkage
220  llvm::ArrayType *ArrayTy = llvm::ArrayType::get(Ty, V.size());
221  return MakeGlobal(ArrayTy, V, Name, linkage);
222  }
223  /// Returns a property name and encoding string.
224  llvm::Constant *MakePropertyEncodingString(const ObjCPropertyDecl *PD,
225  const Decl *Container) {
226  const ObjCRuntime &R = CGM.getLangOpts().ObjCRuntime;
227  if ((R.getKind() == ObjCRuntime::GNUstep) &&
228  (R.getVersion() >= VersionTuple(1, 6))) {
229  std::string NameAndAttributes;
230  std::string TypeStr;
231  CGM.getContext().getObjCEncodingForPropertyDecl(PD, Container, TypeStr);
232  NameAndAttributes += '\0';
233  NameAndAttributes += TypeStr.length() + 3;
234  NameAndAttributes += TypeStr;
235  NameAndAttributes += '\0';
236  NameAndAttributes += PD->getNameAsString();
237  auto *ConstStr = CGM.GetAddrOfConstantCString(NameAndAttributes);
238  return llvm::ConstantExpr::getGetElementPtr(ConstStr->getValueType(),
239  ConstStr, Zeros);
240  }
241  return MakeConstantString(PD->getNameAsString());
242  }
243  /// Push the property attributes into two structure fields.
244  void PushPropertyAttributes(std::vector<llvm::Constant*> &Fields,
245  ObjCPropertyDecl *property, bool isSynthesized=true, bool
246  isDynamic=true) {
247  int attrs = property->getPropertyAttributes();
248  // For read-only properties, clear the copy and retain flags
250  attrs &= ~ObjCPropertyDecl::OBJC_PR_copy;
251  attrs &= ~ObjCPropertyDecl::OBJC_PR_retain;
252  attrs &= ~ObjCPropertyDecl::OBJC_PR_weak;
253  attrs &= ~ObjCPropertyDecl::OBJC_PR_strong;
254  }
255  // The first flags field has the same attribute values as clang uses internally
256  Fields.push_back(llvm::ConstantInt::get(Int8Ty, attrs & 0xff));
257  attrs >>= 8;
258  attrs <<= 2;
259  // For protocol properties, synthesized and dynamic have no meaning, so we
260  // reuse these flags to indicate that this is a protocol property (both set
261  // has no meaning, as a property can't be both synthesized and dynamic)
262  attrs |= isSynthesized ? (1<<0) : 0;
263  attrs |= isDynamic ? (1<<1) : 0;
264  // The second field is the next four fields left shifted by two, with the
265  // low bit set to indicate whether the field is synthesized or dynamic.
266  Fields.push_back(llvm::ConstantInt::get(Int8Ty, attrs & 0xff));
267  // Two padding fields
268  Fields.push_back(llvm::ConstantInt::get(Int8Ty, 0));
269  Fields.push_back(llvm::ConstantInt::get(Int8Ty, 0));
270  }
271  /// Ensures that the value has the required type, by inserting a bitcast if
272  /// required. This function lets us avoid inserting bitcasts that are
273  /// redundant.
274  llvm::Value* EnforceType(CGBuilderTy &B, llvm::Value *V, llvm::Type *Ty) {
275  if (V->getType() == Ty) return V;
276  return B.CreateBitCast(V, Ty);
277  }
278  // Some zeros used for GEPs in lots of places.
279  llvm::Constant *Zeros[2];
280  /// Null pointer value. Mainly used as a terminator in various arrays.
281  llvm::Constant *NULLPtr;
282  /// LLVM context.
283  llvm::LLVMContext &VMContext;
284 private:
285  /// Placeholder for the class. Lots of things refer to the class before we've
286  /// actually emitted it. We use this alias as a placeholder, and then replace
287  /// it with a pointer to the class structure before finally emitting the
288  /// module.
289  llvm::GlobalAlias *ClassPtrAlias;
290  /// Placeholder for the metaclass. Lots of things refer to the class before
291  /// we've / actually emitted it. We use this alias as a placeholder, and then
292  /// replace / it with a pointer to the metaclass structure before finally
293  /// emitting the / module.
294  llvm::GlobalAlias *MetaClassPtrAlias;
295  /// All of the classes that have been generated for this compilation units.
296  std::vector<llvm::Constant*> Classes;
297  /// All of the categories that have been generated for this compilation units.
298  std::vector<llvm::Constant*> Categories;
299  /// All of the Objective-C constant strings that have been generated for this
300  /// compilation units.
301  std::vector<llvm::Constant*> ConstantStrings;
302  /// Map from string values to Objective-C constant strings in the output.
303  /// Used to prevent emitting Objective-C strings more than once. This should
304  /// not be required at all - CodeGenModule should manage this list.
305  llvm::StringMap<llvm::Constant*> ObjCStrings;
306  /// All of the protocols that have been declared.
307  llvm::StringMap<llvm::Constant*> ExistingProtocols;
308  /// For each variant of a selector, we store the type encoding and a
309  /// placeholder value. For an untyped selector, the type will be the empty
310  /// string. Selector references are all done via the module's selector table,
311  /// so we create an alias as a placeholder and then replace it with the real
312  /// value later.
313  typedef std::pair<std::string, llvm::GlobalAlias*> TypedSelector;
314  /// Type of the selector map. This is roughly equivalent to the structure
315  /// used in the GNUstep runtime, which maintains a list of all of the valid
316  /// types for a selector in a table.
317  typedef llvm::DenseMap<Selector, SmallVector<TypedSelector, 2> >
318  SelectorMap;
319  /// A map from selectors to selector types. This allows us to emit all
320  /// selectors of the same name and type together.
321  SelectorMap SelectorTable;
322 
323  /// Selectors related to memory management. When compiling in GC mode, we
324  /// omit these.
325  Selector RetainSel, ReleaseSel, AutoreleaseSel;
326  /// Runtime functions used for memory management in GC mode. Note that clang
327  /// supports code generation for calling these functions, but neither GNU
328  /// runtime actually supports this API properly yet.
329  LazyRuntimeFunction IvarAssignFn, StrongCastAssignFn, MemMoveFn, WeakReadFn,
330  WeakAssignFn, GlobalAssignFn;
331 
332  typedef std::pair<std::string, std::string> ClassAliasPair;
333  /// All classes that have aliases set for them.
334  std::vector<ClassAliasPair> ClassAliases;
335 
336 protected:
337  /// Function used for throwing Objective-C exceptions.
338  LazyRuntimeFunction ExceptionThrowFn;
339  /// Function used for rethrowing exceptions, used at the end of \@finally or
340  /// \@synchronize blocks.
341  LazyRuntimeFunction ExceptionReThrowFn;
342  /// Function called when entering a catch function. This is required for
343  /// differentiating Objective-C exceptions and foreign exceptions.
344  LazyRuntimeFunction EnterCatchFn;
345  /// Function called when exiting from a catch block. Used to do exception
346  /// cleanup.
347  LazyRuntimeFunction ExitCatchFn;
348  /// Function called when entering an \@synchronize block. Acquires the lock.
349  LazyRuntimeFunction SyncEnterFn;
350  /// Function called when exiting an \@synchronize block. Releases the lock.
351  LazyRuntimeFunction SyncExitFn;
352 
353 private:
354 
355  /// Function called if fast enumeration detects that the collection is
356  /// modified during the update.
357  LazyRuntimeFunction EnumerationMutationFn;
358  /// Function for implementing synthesized property getters that return an
359  /// object.
360  LazyRuntimeFunction GetPropertyFn;
361  /// Function for implementing synthesized property setters that return an
362  /// object.
363  LazyRuntimeFunction SetPropertyFn;
364  /// Function used for non-object declared property getters.
365  LazyRuntimeFunction GetStructPropertyFn;
366  /// Function used for non-object declared property setters.
367  LazyRuntimeFunction SetStructPropertyFn;
368 
369  /// The version of the runtime that this class targets. Must match the
370  /// version in the runtime.
371  int RuntimeVersion;
372  /// The version of the protocol class. Used to differentiate between ObjC1
373  /// and ObjC2 protocols. Objective-C 1 protocols can not contain optional
374  /// components and can not contain declared properties. We always emit
375  /// Objective-C 2 property structures, but we have to pretend that they're
376  /// Objective-C 1 property structures when targeting the GCC runtime or it
377  /// will abort.
378  const int ProtocolVersion;
379 private:
380  /// Generates an instance variable list structure. This is a structure
381  /// containing a size and an array of structures containing instance variable
382  /// metadata. This is used purely for introspection in the fragile ABI. In
383  /// the non-fragile ABI, it's used for instance variable fixup.
384  llvm::Constant *GenerateIvarList(ArrayRef<llvm::Constant *> IvarNames,
385  ArrayRef<llvm::Constant *> IvarTypes,
386  ArrayRef<llvm::Constant *> IvarOffsets);
387  /// Generates a method list structure. This is a structure containing a size
388  /// and an array of structures containing method metadata.
389  ///
390  /// This structure is used by both classes and categories, and contains a next
391  /// pointer allowing them to be chained together in a linked list.
392  llvm::Constant *GenerateMethodList(StringRef ClassName,
393  StringRef CategoryName,
394  ArrayRef<Selector> MethodSels,
395  ArrayRef<llvm::Constant *> MethodTypes,
396  bool isClassMethodList);
397  /// Emits an empty protocol. This is used for \@protocol() where no protocol
398  /// is found. The runtime will (hopefully) fix up the pointer to refer to the
399  /// real protocol.
400  llvm::Constant *GenerateEmptyProtocol(const std::string &ProtocolName);
401  /// Generates a list of property metadata structures. This follows the same
402  /// pattern as method and instance variable metadata lists.
403  llvm::Constant *GeneratePropertyList(const ObjCImplementationDecl *OID,
404  SmallVectorImpl<Selector> &InstanceMethodSels,
405  SmallVectorImpl<llvm::Constant*> &InstanceMethodTypes);
406  /// Generates a list of referenced protocols. Classes, categories, and
407  /// protocols all use this structure.
408  llvm::Constant *GenerateProtocolList(ArrayRef<std::string> Protocols);
409  /// To ensure that all protocols are seen by the runtime, we add a category on
410  /// a class defined in the runtime, declaring no methods, but adopting the
411  /// protocols. This is a horribly ugly hack, but it allows us to collect all
412  /// of the protocols without changing the ABI.
413  void GenerateProtocolHolderCategory();
414  /// Generates a class structure.
415  llvm::Constant *GenerateClassStructure(
416  llvm::Constant *MetaClass,
417  llvm::Constant *SuperClass,
418  unsigned info,
419  const char *Name,
420  llvm::Constant *Version,
421  llvm::Constant *InstanceSize,
422  llvm::Constant *IVars,
423  llvm::Constant *Methods,
424  llvm::Constant *Protocols,
425  llvm::Constant *IvarOffsets,
426  llvm::Constant *Properties,
427  llvm::Constant *StrongIvarBitmap,
428  llvm::Constant *WeakIvarBitmap,
429  bool isMeta=false);
430  /// Generates a method list. This is used by protocols to define the required
431  /// and optional methods.
432  llvm::Constant *GenerateProtocolMethodList(
433  ArrayRef<llvm::Constant *> MethodNames,
434  ArrayRef<llvm::Constant *> MethodTypes);
435  /// Returns a selector with the specified type encoding. An empty string is
436  /// used to return an untyped selector (with the types field set to NULL).
437  llvm::Value *GetSelector(CodeGenFunction &CGF, Selector Sel,
438  const std::string &TypeEncoding, bool lval);
439  /// Returns the variable used to store the offset of an instance variable.
440  llvm::GlobalVariable *ObjCIvarOffsetVariable(const ObjCInterfaceDecl *ID,
441  const ObjCIvarDecl *Ivar);
442  /// Emits a reference to a class. This allows the linker to object if there
443  /// is no class of the matching name.
444 protected:
445  void EmitClassRef(const std::string &className);
446  /// Emits a pointer to the named class
447  virtual llvm::Value *GetClassNamed(CodeGenFunction &CGF,
448  const std::string &Name, bool isWeak);
449  /// Looks up the method for sending a message to the specified object. This
450  /// mechanism differs between the GCC and GNU runtimes, so this method must be
451  /// overridden in subclasses.
452  virtual llvm::Value *LookupIMP(CodeGenFunction &CGF,
453  llvm::Value *&Receiver,
454  llvm::Value *cmd,
455  llvm::MDNode *node,
456  MessageSendInfo &MSI) = 0;
457  /// Looks up the method for sending a message to a superclass. This
458  /// mechanism differs between the GCC and GNU runtimes, so this method must
459  /// be overridden in subclasses.
460  virtual llvm::Value *LookupIMPSuper(CodeGenFunction &CGF,
461  llvm::Value *ObjCSuper,
462  llvm::Value *cmd,
463  MessageSendInfo &MSI) = 0;
464  /// Libobjc2 uses a bitfield representation where small(ish) bitfields are
465  /// stored in a 64-bit value with the low bit set to 1 and the remaining 63
466  /// bits set to their values, LSB first, while larger ones are stored in a
467  /// structure of this / form:
468  ///
469  /// struct { int32_t length; int32_t values[length]; };
470  ///
471  /// The values in the array are stored in host-endian format, with the least
472  /// significant bit being assumed to come first in the bitfield. Therefore,
473  /// a bitfield with the 64th bit set will be (int64_t)&{ 2, [0, 1<<31] },
474  /// while a bitfield / with the 63rd bit set will be 1<<64.
475  llvm::Constant *MakeBitField(ArrayRef<bool> bits);
476 public:
477  CGObjCGNU(CodeGenModule &cgm, unsigned runtimeABIVersion,
478  unsigned protocolClassVersion);
479 
480  llvm::Constant *GenerateConstantString(const StringLiteral *) override;
481 
482  RValue
483  GenerateMessageSend(CodeGenFunction &CGF, ReturnValueSlot Return,
484  QualType ResultType, Selector Sel,
485  llvm::Value *Receiver, const CallArgList &CallArgs,
486  const ObjCInterfaceDecl *Class,
487  const ObjCMethodDecl *Method) override;
488  RValue
489  GenerateMessageSendSuper(CodeGenFunction &CGF, ReturnValueSlot Return,
490  QualType ResultType, Selector Sel,
491  const ObjCInterfaceDecl *Class,
492  bool isCategoryImpl, llvm::Value *Receiver,
493  bool IsClassMessage, const CallArgList &CallArgs,
494  const ObjCMethodDecl *Method) override;
495  llvm::Value *GetClass(CodeGenFunction &CGF,
496  const ObjCInterfaceDecl *OID) override;
497  llvm::Value *GetSelector(CodeGenFunction &CGF, Selector Sel,
498  bool lval = false) override;
499  llvm::Value *GetSelector(CodeGenFunction &CGF,
500  const ObjCMethodDecl *Method) override;
501  llvm::Constant *GetEHType(QualType T) override;
502 
503  llvm::Function *GenerateMethod(const ObjCMethodDecl *OMD,
504  const ObjCContainerDecl *CD) override;
505  void GenerateCategory(const ObjCCategoryImplDecl *CMD) override;
506  void GenerateClass(const ObjCImplementationDecl *ClassDecl) override;
507  void RegisterAlias(const ObjCCompatibleAliasDecl *OAD) override;
508  llvm::Value *GenerateProtocolRef(CodeGenFunction &CGF,
509  const ObjCProtocolDecl *PD) override;
510  void GenerateProtocol(const ObjCProtocolDecl *PD) override;
511  llvm::Function *ModuleInitFunction() override;
512  llvm::Constant *GetPropertyGetFunction() override;
513  llvm::Constant *GetPropertySetFunction() override;
514  llvm::Constant *GetOptimizedPropertySetFunction(bool atomic,
515  bool copy) override;
516  llvm::Constant *GetSetStructFunction() override;
517  llvm::Constant *GetGetStructFunction() override;
518  llvm::Constant *GetCppAtomicObjectGetFunction() override;
519  llvm::Constant *GetCppAtomicObjectSetFunction() override;
520  llvm::Constant *EnumerationMutationFunction() override;
521 
522  void EmitTryStmt(CodeGenFunction &CGF,
523  const ObjCAtTryStmt &S) override;
524  void EmitSynchronizedStmt(CodeGenFunction &CGF,
525  const ObjCAtSynchronizedStmt &S) override;
526  void EmitThrowStmt(CodeGenFunction &CGF,
527  const ObjCAtThrowStmt &S,
528  bool ClearInsertionPoint=true) override;
529  llvm::Value * EmitObjCWeakRead(CodeGenFunction &CGF,
530  llvm::Value *AddrWeakObj) override;
531  void EmitObjCWeakAssign(CodeGenFunction &CGF,
532  llvm::Value *src, llvm::Value *dst) override;
533  void EmitObjCGlobalAssign(CodeGenFunction &CGF,
534  llvm::Value *src, llvm::Value *dest,
535  bool threadlocal=false) override;
536  void EmitObjCIvarAssign(CodeGenFunction &CGF, llvm::Value *src,
537  llvm::Value *dest, llvm::Value *ivarOffset) override;
538  void EmitObjCStrongCastAssign(CodeGenFunction &CGF,
539  llvm::Value *src, llvm::Value *dest) override;
540  void EmitGCMemmoveCollectable(CodeGenFunction &CGF, llvm::Value *DestPtr,
541  llvm::Value *SrcPtr,
542  llvm::Value *Size) override;
543  LValue EmitObjCValueForIvar(CodeGenFunction &CGF, QualType ObjectTy,
544  llvm::Value *BaseValue, const ObjCIvarDecl *Ivar,
545  unsigned CVRQualifiers) override;
546  llvm::Value *EmitIvarOffset(CodeGenFunction &CGF,
547  const ObjCInterfaceDecl *Interface,
548  const ObjCIvarDecl *Ivar) override;
549  llvm::Value *EmitNSAutoreleasePoolClassRef(CodeGenFunction &CGF) override;
550  llvm::Constant *BuildGCBlockLayout(CodeGenModule &CGM,
551  const CGBlockInfo &blockInfo) override {
552  return NULLPtr;
553  }
554  llvm::Constant *BuildRCBlockLayout(CodeGenModule &CGM,
555  const CGBlockInfo &blockInfo) override {
556  return NULLPtr;
557  }
558 
559  llvm::Constant *BuildByrefLayout(CodeGenModule &CGM, QualType T) override {
560  return NULLPtr;
561  }
562 
563  llvm::GlobalVariable *GetClassGlobal(const std::string &Name,
564  bool Weak = false) override {
565  return nullptr;
566  }
567 };
568 /// Class representing the legacy GCC Objective-C ABI. This is the default when
569 /// -fobjc-nonfragile-abi is not specified.
570 ///
571 /// The GCC ABI target actually generates code that is approximately compatible
572 /// with the new GNUstep runtime ABI, but refrains from using any features that
573 /// would not work with the GCC runtime. For example, clang always generates
574 /// the extended form of the class structure, and the extra fields are simply
575 /// ignored by GCC libobjc.
576 class CGObjCGCC : public CGObjCGNU {
577  /// The GCC ABI message lookup function. Returns an IMP pointing to the
578  /// method implementation for this message.
579  LazyRuntimeFunction MsgLookupFn;
580  /// The GCC ABI superclass message lookup function. Takes a pointer to a
581  /// structure describing the receiver and the class, and a selector as
582  /// arguments. Returns the IMP for the corresponding method.
583  LazyRuntimeFunction MsgLookupSuperFn;
584 protected:
585  llvm::Value *LookupIMP(CodeGenFunction &CGF, llvm::Value *&Receiver,
586  llvm::Value *cmd, llvm::MDNode *node,
587  MessageSendInfo &MSI) override {
588  CGBuilderTy &Builder = CGF.Builder;
589  llvm::Value *args[] = {
590  EnforceType(Builder, Receiver, IdTy),
591  EnforceType(Builder, cmd, SelectorTy) };
592  llvm::CallSite imp = CGF.EmitRuntimeCallOrInvoke(MsgLookupFn, args);
593  imp->setMetadata(msgSendMDKind, node);
594  return imp.getInstruction();
595  }
596  llvm::Value *LookupIMPSuper(CodeGenFunction &CGF, llvm::Value *ObjCSuper,
597  llvm::Value *cmd, MessageSendInfo &MSI) override {
598  CGBuilderTy &Builder = CGF.Builder;
599  llvm::Value *lookupArgs[] = {EnforceType(Builder, ObjCSuper,
600  PtrToObjCSuperTy), cmd};
601  return CGF.EmitNounwindRuntimeCall(MsgLookupSuperFn, lookupArgs);
602  }
603  public:
604  CGObjCGCC(CodeGenModule &Mod) : CGObjCGNU(Mod, 8, 2) {
605  // IMP objc_msg_lookup(id, SEL);
606  MsgLookupFn.init(&CGM, "objc_msg_lookup", IMPTy, IdTy, SelectorTy,
607  nullptr);
608  // IMP objc_msg_lookup_super(struct objc_super*, SEL);
609  MsgLookupSuperFn.init(&CGM, "objc_msg_lookup_super", IMPTy,
610  PtrToObjCSuperTy, SelectorTy, nullptr);
611  }
612 };
613 /// Class used when targeting the new GNUstep runtime ABI.
614 class CGObjCGNUstep : public CGObjCGNU {
615  /// The slot lookup function. Returns a pointer to a cacheable structure
616  /// that contains (among other things) the IMP.
617  LazyRuntimeFunction SlotLookupFn;
618  /// The GNUstep ABI superclass message lookup function. Takes a pointer to
619  /// a structure describing the receiver and the class, and a selector as
620  /// arguments. Returns the slot for the corresponding method. Superclass
621  /// message lookup rarely changes, so this is a good caching opportunity.
622  LazyRuntimeFunction SlotLookupSuperFn;
623  /// Specialised function for setting atomic retain properties
624  LazyRuntimeFunction SetPropertyAtomic;
625  /// Specialised function for setting atomic copy properties
626  LazyRuntimeFunction SetPropertyAtomicCopy;
627  /// Specialised function for setting nonatomic retain properties
628  LazyRuntimeFunction SetPropertyNonAtomic;
629  /// Specialised function for setting nonatomic copy properties
630  LazyRuntimeFunction SetPropertyNonAtomicCopy;
631  /// Function to perform atomic copies of C++ objects with nontrivial copy
632  /// constructors from Objective-C ivars.
633  LazyRuntimeFunction CxxAtomicObjectGetFn;
634  /// Function to perform atomic copies of C++ objects with nontrivial copy
635  /// constructors to Objective-C ivars.
636  LazyRuntimeFunction CxxAtomicObjectSetFn;
637  /// Type of an slot structure pointer. This is returned by the various
638  /// lookup functions.
639  llvm::Type *SlotTy;
640  public:
641  llvm::Constant *GetEHType(QualType T) override;
642  protected:
643  llvm::Value *LookupIMP(CodeGenFunction &CGF, llvm::Value *&Receiver,
644  llvm::Value *cmd, llvm::MDNode *node,
645  MessageSendInfo &MSI) override {
646  CGBuilderTy &Builder = CGF.Builder;
647  llvm::Function *LookupFn = SlotLookupFn;
648 
649  // Store the receiver on the stack so that we can reload it later
650  llvm::Value *ReceiverPtr = CGF.CreateTempAlloca(Receiver->getType());
651  Builder.CreateStore(Receiver, ReceiverPtr);
652 
653  llvm::Value *self;
654 
655  if (isa<ObjCMethodDecl>(CGF.CurCodeDecl)) {
656  self = CGF.LoadObjCSelf();
657  } else {
658  self = llvm::ConstantPointerNull::get(IdTy);
659  }
660 
661  // The lookup function is guaranteed not to capture the receiver pointer.
662  LookupFn->setDoesNotCapture(1);
663 
664  llvm::Value *args[] = {
665  EnforceType(Builder, ReceiverPtr, PtrToIdTy),
666  EnforceType(Builder, cmd, SelectorTy),
667  EnforceType(Builder, self, IdTy) };
668  llvm::CallSite slot = CGF.EmitRuntimeCallOrInvoke(LookupFn, args);
669  slot.setOnlyReadsMemory();
670  slot->setMetadata(msgSendMDKind, node);
671 
672  // Load the imp from the slot
673  llvm::Value *imp = Builder.CreateLoad(
674  Builder.CreateStructGEP(nullptr, slot.getInstruction(), 4));
675 
676  // The lookup function may have changed the receiver, so make sure we use
677  // the new one.
678  Receiver = Builder.CreateLoad(ReceiverPtr, true);
679  return imp;
680  }
681  llvm::Value *LookupIMPSuper(CodeGenFunction &CGF, llvm::Value *ObjCSuper,
682  llvm::Value *cmd,
683  MessageSendInfo &MSI) override {
684  CGBuilderTy &Builder = CGF.Builder;
685  llvm::Value *lookupArgs[] = {ObjCSuper, cmd};
686 
687  llvm::CallInst *slot =
688  CGF.EmitNounwindRuntimeCall(SlotLookupSuperFn, lookupArgs);
689  slot->setOnlyReadsMemory();
690 
691  return Builder.CreateLoad(Builder.CreateStructGEP(nullptr, slot, 4));
692  }
693  public:
694  CGObjCGNUstep(CodeGenModule &Mod) : CGObjCGNU(Mod, 9, 3) {
695  const ObjCRuntime &R = CGM.getLangOpts().ObjCRuntime;
696 
697  llvm::StructType *SlotStructTy = llvm::StructType::get(PtrTy,
698  PtrTy, PtrTy, IntTy, IMPTy, nullptr);
699  SlotTy = llvm::PointerType::getUnqual(SlotStructTy);
700  // Slot_t objc_msg_lookup_sender(id *receiver, SEL selector, id sender);
701  SlotLookupFn.init(&CGM, "objc_msg_lookup_sender", SlotTy, PtrToIdTy,
702  SelectorTy, IdTy, nullptr);
703  // Slot_t objc_msg_lookup_super(struct objc_super*, SEL);
704  SlotLookupSuperFn.init(&CGM, "objc_slot_lookup_super", SlotTy,
705  PtrToObjCSuperTy, SelectorTy, nullptr);
706  // If we're in ObjC++ mode, then we want to make
707  if (CGM.getLangOpts().CPlusPlus) {
708  llvm::Type *VoidTy = llvm::Type::getVoidTy(VMContext);
709  // void *__cxa_begin_catch(void *e)
710  EnterCatchFn.init(&CGM, "__cxa_begin_catch", PtrTy, PtrTy, nullptr);
711  // void __cxa_end_catch(void)
712  ExitCatchFn.init(&CGM, "__cxa_end_catch", VoidTy, nullptr);
713  // void _Unwind_Resume_or_Rethrow(void*)
714  ExceptionReThrowFn.init(&CGM, "_Unwind_Resume_or_Rethrow", VoidTy,
715  PtrTy, nullptr);
716  } else if (R.getVersion() >= VersionTuple(1, 7)) {
717  llvm::Type *VoidTy = llvm::Type::getVoidTy(VMContext);
718  // id objc_begin_catch(void *e)
719  EnterCatchFn.init(&CGM, "objc_begin_catch", IdTy, PtrTy, nullptr);
720  // void objc_end_catch(void)
721  ExitCatchFn.init(&CGM, "objc_end_catch", VoidTy, nullptr);
722  // void _Unwind_Resume_or_Rethrow(void*)
723  ExceptionReThrowFn.init(&CGM, "objc_exception_rethrow", VoidTy,
724  PtrTy, nullptr);
725  }
726  llvm::Type *VoidTy = llvm::Type::getVoidTy(VMContext);
727  SetPropertyAtomic.init(&CGM, "objc_setProperty_atomic", VoidTy, IdTy,
728  SelectorTy, IdTy, PtrDiffTy, nullptr);
729  SetPropertyAtomicCopy.init(&CGM, "objc_setProperty_atomic_copy", VoidTy,
730  IdTy, SelectorTy, IdTy, PtrDiffTy, nullptr);
731  SetPropertyNonAtomic.init(&CGM, "objc_setProperty_nonatomic", VoidTy,
732  IdTy, SelectorTy, IdTy, PtrDiffTy, nullptr);
733  SetPropertyNonAtomicCopy.init(&CGM, "objc_setProperty_nonatomic_copy",
734  VoidTy, IdTy, SelectorTy, IdTy, PtrDiffTy, nullptr);
735  // void objc_setCppObjectAtomic(void *dest, const void *src, void
736  // *helper);
737  CxxAtomicObjectSetFn.init(&CGM, "objc_setCppObjectAtomic", VoidTy, PtrTy,
738  PtrTy, PtrTy, nullptr);
739  // void objc_getCppObjectAtomic(void *dest, const void *src, void
740  // *helper);
741  CxxAtomicObjectGetFn.init(&CGM, "objc_getCppObjectAtomic", VoidTy, PtrTy,
742  PtrTy, PtrTy, nullptr);
743  }
744  llvm::Constant *GetCppAtomicObjectGetFunction() override {
745  // The optimised functions were added in version 1.7 of the GNUstep
746  // runtime.
747  assert (CGM.getLangOpts().ObjCRuntime.getVersion() >=
748  VersionTuple(1, 7));
749  return CxxAtomicObjectGetFn;
750  }
751  llvm::Constant *GetCppAtomicObjectSetFunction() override {
752  // The optimised functions were added in version 1.7 of the GNUstep
753  // runtime.
754  assert (CGM.getLangOpts().ObjCRuntime.getVersion() >=
755  VersionTuple(1, 7));
756  return CxxAtomicObjectSetFn;
757  }
758  llvm::Constant *GetOptimizedPropertySetFunction(bool atomic,
759  bool copy) override {
760  // The optimised property functions omit the GC check, and so are not
761  // safe to use in GC mode. The standard functions are fast in GC mode,
762  // so there is less advantage in using them.
763  assert ((CGM.getLangOpts().getGC() == LangOptions::NonGC));
764  // The optimised functions were added in version 1.7 of the GNUstep
765  // runtime.
766  assert (CGM.getLangOpts().ObjCRuntime.getVersion() >=
767  VersionTuple(1, 7));
768 
769  if (atomic) {
770  if (copy) return SetPropertyAtomicCopy;
771  return SetPropertyAtomic;
772  }
773 
774  return copy ? SetPropertyNonAtomicCopy : SetPropertyNonAtomic;
775  }
776 };
777 
778 /// Support for the ObjFW runtime.
779 class CGObjCObjFW: public CGObjCGNU {
780 protected:
781  /// The GCC ABI message lookup function. Returns an IMP pointing to the
782  /// method implementation for this message.
783  LazyRuntimeFunction MsgLookupFn;
784  /// stret lookup function. While this does not seem to make sense at the
785  /// first look, this is required to call the correct forwarding function.
786  LazyRuntimeFunction MsgLookupFnSRet;
787  /// The GCC ABI superclass message lookup function. Takes a pointer to a
788  /// structure describing the receiver and the class, and a selector as
789  /// arguments. Returns the IMP for the corresponding method.
790  LazyRuntimeFunction MsgLookupSuperFn, MsgLookupSuperFnSRet;
791 
792  llvm::Value *LookupIMP(CodeGenFunction &CGF, llvm::Value *&Receiver,
793  llvm::Value *cmd, llvm::MDNode *node,
794  MessageSendInfo &MSI) override {
795  CGBuilderTy &Builder = CGF.Builder;
796  llvm::Value *args[] = {
797  EnforceType(Builder, Receiver, IdTy),
798  EnforceType(Builder, cmd, SelectorTy) };
799 
800  llvm::CallSite imp;
801  if (CGM.ReturnTypeUsesSRet(MSI.CallInfo))
802  imp = CGF.EmitRuntimeCallOrInvoke(MsgLookupFnSRet, args);
803  else
804  imp = CGF.EmitRuntimeCallOrInvoke(MsgLookupFn, args);
805 
806  imp->setMetadata(msgSendMDKind, node);
807  return imp.getInstruction();
808  }
809 
810  llvm::Value *LookupIMPSuper(CodeGenFunction &CGF, llvm::Value *ObjCSuper,
811  llvm::Value *cmd, MessageSendInfo &MSI) override {
812  CGBuilderTy &Builder = CGF.Builder;
813  llvm::Value *lookupArgs[] = {EnforceType(Builder, ObjCSuper,
814  PtrToObjCSuperTy), cmd};
815 
816  if (CGM.ReturnTypeUsesSRet(MSI.CallInfo))
817  return CGF.EmitNounwindRuntimeCall(MsgLookupSuperFnSRet, lookupArgs);
818  else
819  return CGF.EmitNounwindRuntimeCall(MsgLookupSuperFn, lookupArgs);
820  }
821 
822  llvm::Value *GetClassNamed(CodeGenFunction &CGF,
823  const std::string &Name, bool isWeak) override {
824  if (isWeak)
825  return CGObjCGNU::GetClassNamed(CGF, Name, isWeak);
826 
827  EmitClassRef(Name);
828 
829  std::string SymbolName = "_OBJC_CLASS_" + Name;
830 
831  llvm::GlobalVariable *ClassSymbol = TheModule.getGlobalVariable(SymbolName);
832 
833  if (!ClassSymbol)
834  ClassSymbol = new llvm::GlobalVariable(TheModule, LongTy, false,
836  nullptr, SymbolName);
837 
838  return ClassSymbol;
839  }
840 
841 public:
842  CGObjCObjFW(CodeGenModule &Mod): CGObjCGNU(Mod, 9, 3) {
843  // IMP objc_msg_lookup(id, SEL);
844  MsgLookupFn.init(&CGM, "objc_msg_lookup", IMPTy, IdTy, SelectorTy, nullptr);
845  MsgLookupFnSRet.init(&CGM, "objc_msg_lookup_stret", IMPTy, IdTy,
846  SelectorTy, nullptr);
847  // IMP objc_msg_lookup_super(struct objc_super*, SEL);
848  MsgLookupSuperFn.init(&CGM, "objc_msg_lookup_super", IMPTy,
849  PtrToObjCSuperTy, SelectorTy, nullptr);
850  MsgLookupSuperFnSRet.init(&CGM, "objc_msg_lookup_super_stret", IMPTy,
851  PtrToObjCSuperTy, SelectorTy, nullptr);
852  }
853 };
854 } // end anonymous namespace
855 
856 
857 /// Emits a reference to a dummy variable which is emitted with each class.
858 /// This ensures that a linker error will be generated when trying to link
859 /// together modules where a referenced class is not defined.
860 void CGObjCGNU::EmitClassRef(const std::string &className) {
861  std::string symbolRef = "__objc_class_ref_" + className;
862  // Don't emit two copies of the same symbol
863  if (TheModule.getGlobalVariable(symbolRef))
864  return;
865  std::string symbolName = "__objc_class_name_" + className;
866  llvm::GlobalVariable *ClassSymbol = TheModule.getGlobalVariable(symbolName);
867  if (!ClassSymbol) {
868  ClassSymbol = new llvm::GlobalVariable(TheModule, LongTy, false,
870  nullptr, symbolName);
871  }
872  new llvm::GlobalVariable(TheModule, ClassSymbol->getType(), true,
873  llvm::GlobalValue::WeakAnyLinkage, ClassSymbol, symbolRef);
874 }
875 
876 static std::string SymbolNameForMethod( StringRef ClassName,
877  StringRef CategoryName, const Selector MethodName,
878  bool isClassMethod) {
879  std::string MethodNameColonStripped = MethodName.getAsString();
880  std::replace(MethodNameColonStripped.begin(), MethodNameColonStripped.end(),
881  ':', '_');
882  return (Twine(isClassMethod ? "_c_" : "_i_") + ClassName + "_" +
883  CategoryName + "_" + MethodNameColonStripped).str();
884 }
885 
886 CGObjCGNU::CGObjCGNU(CodeGenModule &cgm, unsigned runtimeABIVersion,
887  unsigned protocolClassVersion)
888  : CGObjCRuntime(cgm), TheModule(CGM.getModule()),
889  VMContext(cgm.getLLVMContext()), ClassPtrAlias(nullptr),
890  MetaClassPtrAlias(nullptr), RuntimeVersion(runtimeABIVersion),
891  ProtocolVersion(protocolClassVersion) {
892 
893  msgSendMDKind = VMContext.getMDKindID("GNUObjCMessageSend");
894 
895  CodeGenTypes &Types = CGM.getTypes();
896  IntTy = cast<llvm::IntegerType>(
897  Types.ConvertType(CGM.getContext().IntTy));
898  LongTy = cast<llvm::IntegerType>(
899  Types.ConvertType(CGM.getContext().LongTy));
900  SizeTy = cast<llvm::IntegerType>(
901  Types.ConvertType(CGM.getContext().getSizeType()));
902  PtrDiffTy = cast<llvm::IntegerType>(
903  Types.ConvertType(CGM.getContext().getPointerDiffType()));
904  BoolTy = CGM.getTypes().ConvertType(CGM.getContext().BoolTy);
905 
906  Int8Ty = llvm::Type::getInt8Ty(VMContext);
907  // C string type. Used in lots of places.
908  PtrToInt8Ty = llvm::PointerType::getUnqual(Int8Ty);
909 
910  Zeros[0] = llvm::ConstantInt::get(LongTy, 0);
911  Zeros[1] = Zeros[0];
912  NULLPtr = llvm::ConstantPointerNull::get(PtrToInt8Ty);
913  // Get the selector Type.
914  QualType selTy = CGM.getContext().getObjCSelType();
915  if (QualType() == selTy) {
916  SelectorTy = PtrToInt8Ty;
917  } else {
918  SelectorTy = cast<llvm::PointerType>(CGM.getTypes().ConvertType(selTy));
919  }
920 
921  PtrToIntTy = llvm::PointerType::getUnqual(IntTy);
922  PtrTy = PtrToInt8Ty;
923 
924  Int32Ty = llvm::Type::getInt32Ty(VMContext);
925  Int64Ty = llvm::Type::getInt64Ty(VMContext);
926 
927  IntPtrTy =
928  CGM.getDataLayout().getPointerSizeInBits() == 32 ? Int32Ty : Int64Ty;
929 
930  // Object type
931  QualType UnqualIdTy = CGM.getContext().getObjCIdType();
932  ASTIdTy = CanQualType();
933  if (UnqualIdTy != QualType()) {
934  ASTIdTy = CGM.getContext().getCanonicalType(UnqualIdTy);
935  IdTy = cast<llvm::PointerType>(CGM.getTypes().ConvertType(ASTIdTy));
936  } else {
937  IdTy = PtrToInt8Ty;
938  }
939  PtrToIdTy = llvm::PointerType::getUnqual(IdTy);
940 
941  ObjCSuperTy = llvm::StructType::get(IdTy, IdTy, nullptr);
942  PtrToObjCSuperTy = llvm::PointerType::getUnqual(ObjCSuperTy);
943 
944  llvm::Type *VoidTy = llvm::Type::getVoidTy(VMContext);
945 
946  // void objc_exception_throw(id);
947  ExceptionThrowFn.init(&CGM, "objc_exception_throw", VoidTy, IdTy, nullptr);
948  ExceptionReThrowFn.init(&CGM, "objc_exception_throw", VoidTy, IdTy, nullptr);
949  // int objc_sync_enter(id);
950  SyncEnterFn.init(&CGM, "objc_sync_enter", IntTy, IdTy, nullptr);
951  // int objc_sync_exit(id);
952  SyncExitFn.init(&CGM, "objc_sync_exit", IntTy, IdTy, nullptr);
953 
954  // void objc_enumerationMutation (id)
955  EnumerationMutationFn.init(&CGM, "objc_enumerationMutation", VoidTy,
956  IdTy, nullptr);
957 
958  // id objc_getProperty(id, SEL, ptrdiff_t, BOOL)
959  GetPropertyFn.init(&CGM, "objc_getProperty", IdTy, IdTy, SelectorTy,
960  PtrDiffTy, BoolTy, nullptr);
961  // void objc_setProperty(id, SEL, ptrdiff_t, id, BOOL, BOOL)
962  SetPropertyFn.init(&CGM, "objc_setProperty", VoidTy, IdTy, SelectorTy,
963  PtrDiffTy, IdTy, BoolTy, BoolTy, nullptr);
964  // void objc_setPropertyStruct(void*, void*, ptrdiff_t, BOOL, BOOL)
965  GetStructPropertyFn.init(&CGM, "objc_getPropertyStruct", VoidTy, PtrTy, PtrTy,
966  PtrDiffTy, BoolTy, BoolTy, nullptr);
967  // void objc_setPropertyStruct(void*, void*, ptrdiff_t, BOOL, BOOL)
968  SetStructPropertyFn.init(&CGM, "objc_setPropertyStruct", VoidTy, PtrTy, PtrTy,
969  PtrDiffTy, BoolTy, BoolTy, nullptr);
970 
971  // IMP type
972  llvm::Type *IMPArgs[] = { IdTy, SelectorTy };
973  IMPTy = llvm::PointerType::getUnqual(llvm::FunctionType::get(IdTy, IMPArgs,
974  true));
975 
976  const LangOptions &Opts = CGM.getLangOpts();
977  if ((Opts.getGC() != LangOptions::NonGC) || Opts.ObjCAutoRefCount)
978  RuntimeVersion = 10;
979 
980  // Don't bother initialising the GC stuff unless we're compiling in GC mode
981  if (Opts.getGC() != LangOptions::NonGC) {
982  // This is a bit of an hack. We should sort this out by having a proper
983  // CGObjCGNUstep subclass for GC, but we may want to really support the old
984  // ABI and GC added in ObjectiveC2.framework, so we fudge it a bit for now
985  // Get selectors needed in GC mode
986  RetainSel = GetNullarySelector("retain", CGM.getContext());
987  ReleaseSel = GetNullarySelector("release", CGM.getContext());
988  AutoreleaseSel = GetNullarySelector("autorelease", CGM.getContext());
989 
990  // Get functions needed in GC mode
991 
992  // id objc_assign_ivar(id, id, ptrdiff_t);
993  IvarAssignFn.init(&CGM, "objc_assign_ivar", IdTy, IdTy, IdTy, PtrDiffTy,
994  nullptr);
995  // id objc_assign_strongCast (id, id*)
996  StrongCastAssignFn.init(&CGM, "objc_assign_strongCast", IdTy, IdTy,
997  PtrToIdTy, nullptr);
998  // id objc_assign_global(id, id*);
999  GlobalAssignFn.init(&CGM, "objc_assign_global", IdTy, IdTy, PtrToIdTy,
1000  nullptr);
1001  // id objc_assign_weak(id, id*);
1002  WeakAssignFn.init(&CGM, "objc_assign_weak", IdTy, IdTy, PtrToIdTy, nullptr);
1003  // id objc_read_weak(id*);
1004  WeakReadFn.init(&CGM, "objc_read_weak", IdTy, PtrToIdTy, nullptr);
1005  // void *objc_memmove_collectable(void*, void *, size_t);
1006  MemMoveFn.init(&CGM, "objc_memmove_collectable", PtrTy, PtrTy, PtrTy,
1007  SizeTy, nullptr);
1008  }
1009 }
1010 
1011 llvm::Value *CGObjCGNU::GetClassNamed(CodeGenFunction &CGF,
1012  const std::string &Name,
1013  bool isWeak) {
1014  llvm::GlobalVariable *ClassNameGV = CGM.GetAddrOfConstantCString(Name);
1015  // With the incompatible ABI, this will need to be replaced with a direct
1016  // reference to the class symbol. For the compatible nonfragile ABI we are
1017  // still performing this lookup at run time but emitting the symbol for the
1018  // class externally so that we can make the switch later.
1019  //
1020  // Libobjc2 contains an LLVM pass that replaces calls to objc_lookup_class
1021  // with memoized versions or with static references if it's safe to do so.
1022  if (!isWeak)
1023  EmitClassRef(Name);
1024  llvm::Value *ClassName =
1025  CGF.Builder.CreateStructGEP(ClassNameGV->getValueType(), ClassNameGV, 0);
1026 
1027  llvm::Constant *ClassLookupFn =
1028  CGM.CreateRuntimeFunction(llvm::FunctionType::get(IdTy, PtrToInt8Ty, true),
1029  "objc_lookup_class");
1030  return CGF.EmitNounwindRuntimeCall(ClassLookupFn, ClassName);
1031 }
1032 
1033 // This has to perform the lookup every time, since posing and related
1034 // techniques can modify the name -> class mapping.
1035 llvm::Value *CGObjCGNU::GetClass(CodeGenFunction &CGF,
1036  const ObjCInterfaceDecl *OID) {
1037  return GetClassNamed(CGF, OID->getNameAsString(), OID->isWeakImported());
1038 }
1039 llvm::Value *CGObjCGNU::EmitNSAutoreleasePoolClassRef(CodeGenFunction &CGF) {
1040  return GetClassNamed(CGF, "NSAutoreleasePool", false);
1041 }
1042 
1043 llvm::Value *CGObjCGNU::GetSelector(CodeGenFunction &CGF, Selector Sel,
1044  const std::string &TypeEncoding, bool lval) {
1045 
1047  llvm::GlobalAlias *SelValue = nullptr;
1048 
1049  for (SmallVectorImpl<TypedSelector>::iterator i = Types.begin(),
1050  e = Types.end() ; i!=e ; i++) {
1051  if (i->first == TypeEncoding) {
1052  SelValue = i->second;
1053  break;
1054  }
1055  }
1056  if (!SelValue) {
1057  SelValue = llvm::GlobalAlias::create(
1058  SelectorTy, llvm::GlobalValue::PrivateLinkage,
1059  ".objc_selector_" + Sel.getAsString(), &TheModule);
1060  Types.emplace_back(TypeEncoding, SelValue);
1061  }
1062 
1063  if (lval) {
1064  llvm::Value *tmp = CGF.CreateTempAlloca(SelValue->getType());
1065  CGF.Builder.CreateStore(SelValue, tmp);
1066  return tmp;
1067  }
1068  return SelValue;
1069 }
1070 
1071 llvm::Value *CGObjCGNU::GetSelector(CodeGenFunction &CGF, Selector Sel,
1072  bool lval) {
1073  return GetSelector(CGF, Sel, std::string(), lval);
1074 }
1075 
1076 llvm::Value *CGObjCGNU::GetSelector(CodeGenFunction &CGF,
1077  const ObjCMethodDecl *Method) {
1078  std::string SelTypes;
1079  CGM.getContext().getObjCEncodingForMethodDecl(Method, SelTypes);
1080  return GetSelector(CGF, Method->getSelector(), SelTypes, false);
1081 }
1082 
1083 llvm::Constant *CGObjCGNU::GetEHType(QualType T) {
1084  if (T->isObjCIdType() || T->isObjCQualifiedIdType()) {
1085  // With the old ABI, there was only one kind of catchall, which broke
1086  // foreign exceptions. With the new ABI, we use __objc_id_typeinfo as
1087  // a pointer indicating object catchalls, and NULL to indicate real
1088  // catchalls
1089  if (CGM.getLangOpts().ObjCRuntime.isNonFragile()) {
1090  return MakeConstantString("@id");
1091  } else {
1092  return nullptr;
1093  }
1094  }
1095 
1096  // All other types should be Objective-C interface pointer types.
1098  assert(OPT && "Invalid @catch type.");
1099  const ObjCInterfaceDecl *IDecl = OPT->getObjectType()->getInterface();
1100  assert(IDecl && "Invalid @catch type.");
1101  return MakeConstantString(IDecl->getIdentifier()->getName());
1102 }
1103 
1104 llvm::Constant *CGObjCGNUstep::GetEHType(QualType T) {
1105  if (!CGM.getLangOpts().CPlusPlus)
1106  return CGObjCGNU::GetEHType(T);
1107 
1108  // For Objective-C++, we want to provide the ability to catch both C++ and
1109  // Objective-C objects in the same function.
1110 
1111  // There's a particular fixed type info for 'id'.
1112  if (T->isObjCIdType() ||
1113  T->isObjCQualifiedIdType()) {
1114  llvm::Constant *IDEHType =
1115  CGM.getModule().getGlobalVariable("__objc_id_type_info");
1116  if (!IDEHType)
1117  IDEHType =
1118  new llvm::GlobalVariable(CGM.getModule(), PtrToInt8Ty,
1119  false,
1121  nullptr, "__objc_id_type_info");
1122  return llvm::ConstantExpr::getBitCast(IDEHType, PtrToInt8Ty);
1123  }
1124 
1125  const ObjCObjectPointerType *PT =
1127  assert(PT && "Invalid @catch type.");
1128  const ObjCInterfaceType *IT = PT->getInterfaceType();
1129  assert(IT && "Invalid @catch type.");
1130  std::string className = IT->getDecl()->getIdentifier()->getName();
1131 
1132  std::string typeinfoName = "__objc_eh_typeinfo_" + className;
1133 
1134  // Return the existing typeinfo if it exists
1135  llvm::Constant *typeinfo = TheModule.getGlobalVariable(typeinfoName);
1136  if (typeinfo)
1137  return llvm::ConstantExpr::getBitCast(typeinfo, PtrToInt8Ty);
1138 
1139  // Otherwise create it.
1140 
1141  // vtable for gnustep::libobjc::__objc_class_type_info
1142  // It's quite ugly hard-coding this. Ideally we'd generate it using the host
1143  // platform's name mangling.
1144  const char *vtableName = "_ZTVN7gnustep7libobjc22__objc_class_type_infoE";
1145  auto *Vtable = TheModule.getGlobalVariable(vtableName);
1146  if (!Vtable) {
1147  Vtable = new llvm::GlobalVariable(TheModule, PtrToInt8Ty, true,
1149  nullptr, vtableName);
1150  }
1151  llvm::Constant *Two = llvm::ConstantInt::get(IntTy, 2);
1152  auto *BVtable = llvm::ConstantExpr::getBitCast(
1153  llvm::ConstantExpr::getGetElementPtr(Vtable->getValueType(), Vtable, Two),
1154  PtrToInt8Ty);
1155 
1156  llvm::Constant *typeName =
1157  ExportUniqueString(className, "__objc_eh_typename_");
1158 
1159  std::vector<llvm::Constant*> fields;
1160  fields.push_back(BVtable);
1161  fields.push_back(typeName);
1162  llvm::Constant *TI =
1163  MakeGlobal(llvm::StructType::get(PtrToInt8Ty, PtrToInt8Ty,
1164  nullptr), fields, "__objc_eh_typeinfo_" + className,
1165  llvm::GlobalValue::LinkOnceODRLinkage);
1166  return llvm::ConstantExpr::getBitCast(TI, PtrToInt8Ty);
1167 }
1168 
1169 /// Generate an NSConstantString object.
1170 llvm::Constant *CGObjCGNU::GenerateConstantString(const StringLiteral *SL) {
1171 
1172  std::string Str = SL->getString().str();
1173 
1174  // Look for an existing one
1175  llvm::StringMap<llvm::Constant*>::iterator old = ObjCStrings.find(Str);
1176  if (old != ObjCStrings.end())
1177  return old->getValue();
1178 
1179  StringRef StringClass = CGM.getLangOpts().ObjCConstantStringClass;
1180 
1181  if (StringClass.empty()) StringClass = "NXConstantString";
1182 
1183  std::string Sym = "_OBJC_CLASS_";
1184  Sym += StringClass;
1185 
1186  llvm::Constant *isa = TheModule.getNamedGlobal(Sym);
1187 
1188  if (!isa)
1189  isa = new llvm::GlobalVariable(TheModule, IdTy, /* isConstant */false,
1190  llvm::GlobalValue::ExternalWeakLinkage, nullptr, Sym);
1191  else if (isa->getType() != PtrToIdTy)
1192  isa = llvm::ConstantExpr::getBitCast(isa, PtrToIdTy);
1193 
1194  std::vector<llvm::Constant*> Ivars;
1195  Ivars.push_back(isa);
1196  Ivars.push_back(MakeConstantString(Str));
1197  Ivars.push_back(llvm::ConstantInt::get(IntTy, Str.size()));
1198  llvm::Constant *ObjCStr = MakeGlobal(
1199  llvm::StructType::get(PtrToIdTy, PtrToInt8Ty, IntTy, nullptr),
1200  Ivars, ".objc_str");
1201  ObjCStr = llvm::ConstantExpr::getBitCast(ObjCStr, PtrToInt8Ty);
1202  ObjCStrings[Str] = ObjCStr;
1203  ConstantStrings.push_back(ObjCStr);
1204  return ObjCStr;
1205 }
1206 
1207 ///Generates a message send where the super is the receiver. This is a message
1208 ///send to self with special delivery semantics indicating which class's method
1209 ///should be called.
1210 RValue
1211 CGObjCGNU::GenerateMessageSendSuper(CodeGenFunction &CGF,
1212  ReturnValueSlot Return,
1213  QualType ResultType,
1214  Selector Sel,
1215  const ObjCInterfaceDecl *Class,
1216  bool isCategoryImpl,
1217  llvm::Value *Receiver,
1218  bool IsClassMessage,
1219  const CallArgList &CallArgs,
1220  const ObjCMethodDecl *Method) {
1221  CGBuilderTy &Builder = CGF.Builder;
1222  if (CGM.getLangOpts().getGC() == LangOptions::GCOnly) {
1223  if (Sel == RetainSel || Sel == AutoreleaseSel) {
1224  return RValue::get(EnforceType(Builder, Receiver,
1225  CGM.getTypes().ConvertType(ResultType)));
1226  }
1227  if (Sel == ReleaseSel) {
1228  return RValue::get(nullptr);
1229  }
1230  }
1231 
1232  llvm::Value *cmd = GetSelector(CGF, Sel);
1233 
1234 
1235  CallArgList ActualArgs;
1236 
1237  ActualArgs.add(RValue::get(EnforceType(Builder, Receiver, IdTy)), ASTIdTy);
1238  ActualArgs.add(RValue::get(cmd), CGF.getContext().getObjCSelType());
1239  ActualArgs.addFrom(CallArgs);
1240 
1241  MessageSendInfo MSI = getMessageSendInfo(Method, ResultType, ActualArgs);
1242 
1243  llvm::Value *ReceiverClass = nullptr;
1244  if (isCategoryImpl) {
1245  llvm::Constant *classLookupFunction = nullptr;
1246  if (IsClassMessage) {
1247  classLookupFunction = CGM.CreateRuntimeFunction(llvm::FunctionType::get(
1248  IdTy, PtrTy, true), "objc_get_meta_class");
1249  } else {
1250  classLookupFunction = CGM.CreateRuntimeFunction(llvm::FunctionType::get(
1251  IdTy, PtrTy, true), "objc_get_class");
1252  }
1253  ReceiverClass = Builder.CreateCall(classLookupFunction,
1254  MakeConstantString(Class->getNameAsString()));
1255  } else {
1256  // Set up global aliases for the metaclass or class pointer if they do not
1257  // already exist. These will are forward-references which will be set to
1258  // pointers to the class and metaclass structure created for the runtime
1259  // load function. To send a message to super, we look up the value of the
1260  // super_class pointer from either the class or metaclass structure.
1261  if (IsClassMessage) {
1262  if (!MetaClassPtrAlias) {
1263  MetaClassPtrAlias = llvm::GlobalAlias::create(
1265  ".objc_metaclass_ref" + Class->getNameAsString(), &TheModule);
1266  }
1267  ReceiverClass = MetaClassPtrAlias;
1268  } else {
1269  if (!ClassPtrAlias) {
1270  ClassPtrAlias = llvm::GlobalAlias::create(
1272  ".objc_class_ref" + Class->getNameAsString(), &TheModule);
1273  }
1274  ReceiverClass = ClassPtrAlias;
1275  }
1276  }
1277  // Cast the pointer to a simplified version of the class structure
1278  llvm::Type *CastTy = llvm::StructType::get(IdTy, IdTy, nullptr);
1279  ReceiverClass = Builder.CreateBitCast(ReceiverClass,
1280  llvm::PointerType::getUnqual(CastTy));
1281  // Get the superclass pointer
1282  ReceiverClass = Builder.CreateStructGEP(CastTy, ReceiverClass, 1);
1283  // Load the superclass pointer
1284  ReceiverClass = Builder.CreateLoad(ReceiverClass);
1285  // Construct the structure used to look up the IMP
1286  llvm::StructType *ObjCSuperTy = llvm::StructType::get(
1287  Receiver->getType(), IdTy, nullptr);
1288  llvm::Value *ObjCSuper = Builder.CreateAlloca(ObjCSuperTy);
1289 
1290  Builder.CreateStore(Receiver,
1291  Builder.CreateStructGEP(ObjCSuperTy, ObjCSuper, 0));
1292  Builder.CreateStore(ReceiverClass,
1293  Builder.CreateStructGEP(ObjCSuperTy, ObjCSuper, 1));
1294 
1295  ObjCSuper = EnforceType(Builder, ObjCSuper, PtrToObjCSuperTy);
1296 
1297  // Get the IMP
1298  llvm::Value *imp = LookupIMPSuper(CGF, ObjCSuper, cmd, MSI);
1299  imp = EnforceType(Builder, imp, MSI.MessengerType);
1300 
1301  llvm::Metadata *impMD[] = {
1302  llvm::MDString::get(VMContext, Sel.getAsString()),
1303  llvm::MDString::get(VMContext, Class->getSuperClass()->getNameAsString()),
1304  llvm::ConstantAsMetadata::get(llvm::ConstantInt::get(
1305  llvm::Type::getInt1Ty(VMContext), IsClassMessage))};
1306  llvm::MDNode *node = llvm::MDNode::get(VMContext, impMD);
1307 
1308  llvm::Instruction *call;
1309  RValue msgRet = CGF.EmitCall(MSI.CallInfo, imp, Return, ActualArgs, nullptr,
1310  &call);
1311  call->setMetadata(msgSendMDKind, node);
1312  return msgRet;
1313 }
1314 
1315 /// Generate code for a message send expression.
1316 RValue
1317 CGObjCGNU::GenerateMessageSend(CodeGenFunction &CGF,
1318  ReturnValueSlot Return,
1319  QualType ResultType,
1320  Selector Sel,
1321  llvm::Value *Receiver,
1322  const CallArgList &CallArgs,
1323  const ObjCInterfaceDecl *Class,
1324  const ObjCMethodDecl *Method) {
1325  CGBuilderTy &Builder = CGF.Builder;
1326 
1327  // Strip out message sends to retain / release in GC mode
1328  if (CGM.getLangOpts().getGC() == LangOptions::GCOnly) {
1329  if (Sel == RetainSel || Sel == AutoreleaseSel) {
1330  return RValue::get(EnforceType(Builder, Receiver,
1331  CGM.getTypes().ConvertType(ResultType)));
1332  }
1333  if (Sel == ReleaseSel) {
1334  return RValue::get(nullptr);
1335  }
1336  }
1337 
1338  // If the return type is something that goes in an integer register, the
1339  // runtime will handle 0 returns. For other cases, we fill in the 0 value
1340  // ourselves.
1341  //
1342  // The language spec says the result of this kind of message send is
1343  // undefined, but lots of people seem to have forgotten to read that
1344  // paragraph and insist on sending messages to nil that have structure
1345  // returns. With GCC, this generates a random return value (whatever happens
1346  // to be on the stack / in those registers at the time) on most platforms,
1347  // and generates an illegal instruction trap on SPARC. With LLVM it corrupts
1348  // the stack.
1349  bool isPointerSizedReturn = (ResultType->isAnyPointerType() ||
1350  ResultType->isIntegralOrEnumerationType() || ResultType->isVoidType());
1351 
1352  llvm::BasicBlock *startBB = nullptr;
1353  llvm::BasicBlock *messageBB = nullptr;
1354  llvm::BasicBlock *continueBB = nullptr;
1355 
1356  if (!isPointerSizedReturn) {
1357  startBB = Builder.GetInsertBlock();
1358  messageBB = CGF.createBasicBlock("msgSend");
1359  continueBB = CGF.createBasicBlock("continue");
1360 
1361  llvm::Value *isNil = Builder.CreateICmpEQ(Receiver,
1362  llvm::Constant::getNullValue(Receiver->getType()));
1363  Builder.CreateCondBr(isNil, continueBB, messageBB);
1364  CGF.EmitBlock(messageBB);
1365  }
1366 
1367  IdTy = cast<llvm::PointerType>(CGM.getTypes().ConvertType(ASTIdTy));
1368  llvm::Value *cmd;
1369  if (Method)
1370  cmd = GetSelector(CGF, Method);
1371  else
1372  cmd = GetSelector(CGF, Sel);
1373  cmd = EnforceType(Builder, cmd, SelectorTy);
1374  Receiver = EnforceType(Builder, Receiver, IdTy);
1375 
1376  llvm::Metadata *impMD[] = {
1377  llvm::MDString::get(VMContext, Sel.getAsString()),
1378  llvm::MDString::get(VMContext, Class ? Class->getNameAsString() : ""),
1379  llvm::ConstantAsMetadata::get(llvm::ConstantInt::get(
1380  llvm::Type::getInt1Ty(VMContext), Class != nullptr))};
1381  llvm::MDNode *node = llvm::MDNode::get(VMContext, impMD);
1382 
1383  CallArgList ActualArgs;
1384  ActualArgs.add(RValue::get(Receiver), ASTIdTy);
1385  ActualArgs.add(RValue::get(cmd), CGF.getContext().getObjCSelType());
1386  ActualArgs.addFrom(CallArgs);
1387 
1388  MessageSendInfo MSI = getMessageSendInfo(Method, ResultType, ActualArgs);
1389 
1390  // Get the IMP to call
1391  llvm::Value *imp;
1392 
1393  // If we have non-legacy dispatch specified, we try using the objc_msgSend()
1394  // functions. These are not supported on all platforms (or all runtimes on a
1395  // given platform), so we
1396  switch (CGM.getCodeGenOpts().getObjCDispatchMethod()) {
1397  case CodeGenOptions::Legacy:
1398  imp = LookupIMP(CGF, Receiver, cmd, node, MSI);
1399  break;
1400  case CodeGenOptions::Mixed:
1401  case CodeGenOptions::NonLegacy:
1402  if (CGM.ReturnTypeUsesFPRet(ResultType)) {
1403  imp = CGM.CreateRuntimeFunction(llvm::FunctionType::get(IdTy, IdTy, true),
1404  "objc_msgSend_fpret");
1405  } else if (CGM.ReturnTypeUsesSRet(MSI.CallInfo)) {
1406  // The actual types here don't matter - we're going to bitcast the
1407  // function anyway
1408  imp = CGM.CreateRuntimeFunction(llvm::FunctionType::get(IdTy, IdTy, true),
1409  "objc_msgSend_stret");
1410  } else {
1411  imp = CGM.CreateRuntimeFunction(llvm::FunctionType::get(IdTy, IdTy, true),
1412  "objc_msgSend");
1413  }
1414  }
1415 
1416  // Reset the receiver in case the lookup modified it
1417  ActualArgs[0] = CallArg(RValue::get(Receiver), ASTIdTy, false);
1418 
1419  imp = EnforceType(Builder, imp, MSI.MessengerType);
1420 
1421  llvm::Instruction *call;
1422  RValue msgRet = CGF.EmitCall(MSI.CallInfo, imp, Return, ActualArgs, nullptr,
1423  &call);
1424  call->setMetadata(msgSendMDKind, node);
1425 
1426 
1427  if (!isPointerSizedReturn) {
1428  messageBB = CGF.Builder.GetInsertBlock();
1429  CGF.Builder.CreateBr(continueBB);
1430  CGF.EmitBlock(continueBB);
1431  if (msgRet.isScalar()) {
1432  llvm::Value *v = msgRet.getScalarVal();
1433  llvm::PHINode *phi = Builder.CreatePHI(v->getType(), 2);
1434  phi->addIncoming(v, messageBB);
1435  phi->addIncoming(llvm::Constant::getNullValue(v->getType()), startBB);
1436  msgRet = RValue::get(phi);
1437  } else if (msgRet.isAggregate()) {
1438  llvm::Value *v = msgRet.getAggregateAddr();
1439  llvm::PHINode *phi = Builder.CreatePHI(v->getType(), 2);
1440  llvm::PointerType *RetTy = cast<llvm::PointerType>(v->getType());
1441  llvm::AllocaInst *NullVal =
1442  CGF.CreateTempAlloca(RetTy->getElementType(), "null");
1443  CGF.InitTempAlloca(NullVal,
1444  llvm::Constant::getNullValue(RetTy->getElementType()));
1445  phi->addIncoming(v, messageBB);
1446  phi->addIncoming(NullVal, startBB);
1447  msgRet = RValue::getAggregate(phi);
1448  } else /* isComplex() */ {
1449  std::pair<llvm::Value*,llvm::Value*> v = msgRet.getComplexVal();
1450  llvm::PHINode *phi = Builder.CreatePHI(v.first->getType(), 2);
1451  phi->addIncoming(v.first, messageBB);
1452  phi->addIncoming(llvm::Constant::getNullValue(v.first->getType()),
1453  startBB);
1454  llvm::PHINode *phi2 = Builder.CreatePHI(v.second->getType(), 2);
1455  phi2->addIncoming(v.second, messageBB);
1456  phi2->addIncoming(llvm::Constant::getNullValue(v.second->getType()),
1457  startBB);
1458  msgRet = RValue::getComplex(phi, phi2);
1459  }
1460  }
1461  return msgRet;
1462 }
1463 
1464 /// Generates a MethodList. Used in construction of a objc_class and
1465 /// objc_category structures.
1466 llvm::Constant *CGObjCGNU::
1467 GenerateMethodList(StringRef ClassName,
1468  StringRef CategoryName,
1469  ArrayRef<Selector> MethodSels,
1470  ArrayRef<llvm::Constant *> MethodTypes,
1471  bool isClassMethodList) {
1472  if (MethodSels.empty())
1473  return NULLPtr;
1474  // Get the method structure type.
1475  llvm::StructType *ObjCMethodTy = llvm::StructType::get(
1476  PtrToInt8Ty, // Really a selector, but the runtime creates it us.
1477  PtrToInt8Ty, // Method types
1478  IMPTy, //Method pointer
1479  nullptr);
1480  std::vector<llvm::Constant*> Methods;
1481  std::vector<llvm::Constant*> Elements;
1482  for (unsigned int i = 0, e = MethodTypes.size(); i < e; ++i) {
1483  Elements.clear();
1484  llvm::Constant *Method =
1485  TheModule.getFunction(SymbolNameForMethod(ClassName, CategoryName,
1486  MethodSels[i],
1487  isClassMethodList));
1488  assert(Method && "Can't generate metadata for method that doesn't exist");
1489  llvm::Constant *C = MakeConstantString(MethodSels[i].getAsString());
1490  Elements.push_back(C);
1491  Elements.push_back(MethodTypes[i]);
1492  Method = llvm::ConstantExpr::getBitCast(Method,
1493  IMPTy);
1494  Elements.push_back(Method);
1495  Methods.push_back(llvm::ConstantStruct::get(ObjCMethodTy, Elements));
1496  }
1497 
1498  // Array of method structures
1499  llvm::ArrayType *ObjCMethodArrayTy = llvm::ArrayType::get(ObjCMethodTy,
1500  Methods.size());
1501  llvm::Constant *MethodArray = llvm::ConstantArray::get(ObjCMethodArrayTy,
1502  Methods);
1503 
1504  // Structure containing list pointer, array and array count
1505  llvm::StructType *ObjCMethodListTy = llvm::StructType::create(VMContext);
1506  llvm::Type *NextPtrTy = llvm::PointerType::getUnqual(ObjCMethodListTy);
1507  ObjCMethodListTy->setBody(
1508  NextPtrTy,
1509  IntTy,
1510  ObjCMethodArrayTy,
1511  nullptr);
1512 
1513  Methods.clear();
1514  Methods.push_back(llvm::ConstantPointerNull::get(
1515  llvm::PointerType::getUnqual(ObjCMethodListTy)));
1516  Methods.push_back(llvm::ConstantInt::get(Int32Ty, MethodTypes.size()));
1517  Methods.push_back(MethodArray);
1518 
1519  // Create an instance of the structure
1520  return MakeGlobal(ObjCMethodListTy, Methods, ".objc_method_list");
1521 }
1522 
1523 /// Generates an IvarList. Used in construction of a objc_class.
1524 llvm::Constant *CGObjCGNU::
1525 GenerateIvarList(ArrayRef<llvm::Constant *> IvarNames,
1526  ArrayRef<llvm::Constant *> IvarTypes,
1527  ArrayRef<llvm::Constant *> IvarOffsets) {
1528  if (IvarNames.size() == 0)
1529  return NULLPtr;
1530  // Get the method structure type.
1531  llvm::StructType *ObjCIvarTy = llvm::StructType::get(
1532  PtrToInt8Ty,
1533  PtrToInt8Ty,
1534  IntTy,
1535  nullptr);
1536  std::vector<llvm::Constant*> Ivars;
1537  std::vector<llvm::Constant*> Elements;
1538  for (unsigned int i = 0, e = IvarNames.size() ; i < e ; i++) {
1539  Elements.clear();
1540  Elements.push_back(IvarNames[i]);
1541  Elements.push_back(IvarTypes[i]);
1542  Elements.push_back(IvarOffsets[i]);
1543  Ivars.push_back(llvm::ConstantStruct::get(ObjCIvarTy, Elements));
1544  }
1545 
1546  // Array of method structures
1547  llvm::ArrayType *ObjCIvarArrayTy = llvm::ArrayType::get(ObjCIvarTy,
1548  IvarNames.size());
1549 
1550 
1551  Elements.clear();
1552  Elements.push_back(llvm::ConstantInt::get(IntTy, (int)IvarNames.size()));
1553  Elements.push_back(llvm::ConstantArray::get(ObjCIvarArrayTy, Ivars));
1554  // Structure containing array and array count
1555  llvm::StructType *ObjCIvarListTy = llvm::StructType::get(IntTy,
1556  ObjCIvarArrayTy,
1557  nullptr);
1558 
1559  // Create an instance of the structure
1560  return MakeGlobal(ObjCIvarListTy, Elements, ".objc_ivar_list");
1561 }
1562 
1563 /// Generate a class structure
1564 llvm::Constant *CGObjCGNU::GenerateClassStructure(
1565  llvm::Constant *MetaClass,
1566  llvm::Constant *SuperClass,
1567  unsigned info,
1568  const char *Name,
1569  llvm::Constant *Version,
1570  llvm::Constant *InstanceSize,
1571  llvm::Constant *IVars,
1572  llvm::Constant *Methods,
1573  llvm::Constant *Protocols,
1574  llvm::Constant *IvarOffsets,
1575  llvm::Constant *Properties,
1576  llvm::Constant *StrongIvarBitmap,
1577  llvm::Constant *WeakIvarBitmap,
1578  bool isMeta) {
1579  // Set up the class structure
1580  // Note: Several of these are char*s when they should be ids. This is
1581  // because the runtime performs this translation on load.
1582  //
1583  // Fields marked New ABI are part of the GNUstep runtime. We emit them
1584  // anyway; the classes will still work with the GNU runtime, they will just
1585  // be ignored.
1586  llvm::StructType *ClassTy = llvm::StructType::get(
1587  PtrToInt8Ty, // isa
1588  PtrToInt8Ty, // super_class
1589  PtrToInt8Ty, // name
1590  LongTy, // version
1591  LongTy, // info
1592  LongTy, // instance_size
1593  IVars->getType(), // ivars
1594  Methods->getType(), // methods
1595  // These are all filled in by the runtime, so we pretend
1596  PtrTy, // dtable
1597  PtrTy, // subclass_list
1598  PtrTy, // sibling_class
1599  PtrTy, // protocols
1600  PtrTy, // gc_object_type
1601  // New ABI:
1602  LongTy, // abi_version
1603  IvarOffsets->getType(), // ivar_offsets
1604  Properties->getType(), // properties
1605  IntPtrTy, // strong_pointers
1606  IntPtrTy, // weak_pointers
1607  nullptr);
1608  llvm::Constant *Zero = llvm::ConstantInt::get(LongTy, 0);
1609  // Fill in the structure
1610  std::vector<llvm::Constant*> Elements;
1611  Elements.push_back(llvm::ConstantExpr::getBitCast(MetaClass, PtrToInt8Ty));
1612  Elements.push_back(SuperClass);
1613  Elements.push_back(MakeConstantString(Name, ".class_name"));
1614  Elements.push_back(Zero);
1615  Elements.push_back(llvm::ConstantInt::get(LongTy, info));
1616  if (isMeta) {
1617  llvm::DataLayout td(&TheModule);
1618  Elements.push_back(
1619  llvm::ConstantInt::get(LongTy,
1620  td.getTypeSizeInBits(ClassTy) /
1621  CGM.getContext().getCharWidth()));
1622  } else
1623  Elements.push_back(InstanceSize);
1624  Elements.push_back(IVars);
1625  Elements.push_back(Methods);
1626  Elements.push_back(NULLPtr);
1627  Elements.push_back(NULLPtr);
1628  Elements.push_back(NULLPtr);
1629  Elements.push_back(llvm::ConstantExpr::getBitCast(Protocols, PtrTy));
1630  Elements.push_back(NULLPtr);
1631  Elements.push_back(llvm::ConstantInt::get(LongTy, 1));
1632  Elements.push_back(IvarOffsets);
1633  Elements.push_back(Properties);
1634  Elements.push_back(StrongIvarBitmap);
1635  Elements.push_back(WeakIvarBitmap);
1636  // Create an instance of the structure
1637  // This is now an externally visible symbol, so that we can speed up class
1638  // messages in the next ABI. We may already have some weak references to
1639  // this, so check and fix them properly.
1640  std::string ClassSym((isMeta ? "_OBJC_METACLASS_": "_OBJC_CLASS_") +
1641  std::string(Name));
1642  llvm::GlobalVariable *ClassRef = TheModule.getNamedGlobal(ClassSym);
1643  llvm::Constant *Class = MakeGlobal(ClassTy, Elements, ClassSym,
1645  if (ClassRef) {
1646  ClassRef->replaceAllUsesWith(llvm::ConstantExpr::getBitCast(Class,
1647  ClassRef->getType()));
1648  ClassRef->removeFromParent();
1649  Class->setName(ClassSym);
1650  }
1651  return Class;
1652 }
1653 
1654 llvm::Constant *CGObjCGNU::
1655 GenerateProtocolMethodList(ArrayRef<llvm::Constant *> MethodNames,
1656  ArrayRef<llvm::Constant *> MethodTypes) {
1657  // Get the method structure type.
1658  llvm::StructType *ObjCMethodDescTy = llvm::StructType::get(
1659  PtrToInt8Ty, // Really a selector, but the runtime does the casting for us.
1660  PtrToInt8Ty,
1661  nullptr);
1662  std::vector<llvm::Constant*> Methods;
1663  std::vector<llvm::Constant*> Elements;
1664  for (unsigned int i = 0, e = MethodTypes.size() ; i < e ; i++) {
1665  Elements.clear();
1666  Elements.push_back(MethodNames[i]);
1667  Elements.push_back(MethodTypes[i]);
1668  Methods.push_back(llvm::ConstantStruct::get(ObjCMethodDescTy, Elements));
1669  }
1670  llvm::ArrayType *ObjCMethodArrayTy = llvm::ArrayType::get(ObjCMethodDescTy,
1671  MethodNames.size());
1672  llvm::Constant *Array = llvm::ConstantArray::get(ObjCMethodArrayTy,
1673  Methods);
1674  llvm::StructType *ObjCMethodDescListTy = llvm::StructType::get(
1675  IntTy, ObjCMethodArrayTy, nullptr);
1676  Methods.clear();
1677  Methods.push_back(llvm::ConstantInt::get(IntTy, MethodNames.size()));
1678  Methods.push_back(Array);
1679  return MakeGlobal(ObjCMethodDescListTy, Methods, ".objc_method_list");
1680 }
1681 
1682 // Create the protocol list structure used in classes, categories and so on
1683 llvm::Constant *CGObjCGNU::GenerateProtocolList(ArrayRef<std::string>Protocols){
1684  llvm::ArrayType *ProtocolArrayTy = llvm::ArrayType::get(PtrToInt8Ty,
1685  Protocols.size());
1686  llvm::StructType *ProtocolListTy = llvm::StructType::get(
1687  PtrTy, //Should be a recurisve pointer, but it's always NULL here.
1688  SizeTy,
1689  ProtocolArrayTy,
1690  nullptr);
1691  std::vector<llvm::Constant*> Elements;
1692  for (const std::string *iter = Protocols.begin(), *endIter = Protocols.end();
1693  iter != endIter ; iter++) {
1694  llvm::Constant *protocol = nullptr;
1695  llvm::StringMap<llvm::Constant*>::iterator value =
1696  ExistingProtocols.find(*iter);
1697  if (value == ExistingProtocols.end()) {
1698  protocol = GenerateEmptyProtocol(*iter);
1699  } else {
1700  protocol = value->getValue();
1701  }
1702  llvm::Constant *Ptr = llvm::ConstantExpr::getBitCast(protocol,
1703  PtrToInt8Ty);
1704  Elements.push_back(Ptr);
1705  }
1706  llvm::Constant * ProtocolArray = llvm::ConstantArray::get(ProtocolArrayTy,
1707  Elements);
1708  Elements.clear();
1709  Elements.push_back(NULLPtr);
1710  Elements.push_back(llvm::ConstantInt::get(LongTy, Protocols.size()));
1711  Elements.push_back(ProtocolArray);
1712  return MakeGlobal(ProtocolListTy, Elements, ".objc_protocol_list");
1713 }
1714 
1715 llvm::Value *CGObjCGNU::GenerateProtocolRef(CodeGenFunction &CGF,
1716  const ObjCProtocolDecl *PD) {
1717  llvm::Value *protocol = ExistingProtocols[PD->getNameAsString()];
1718  llvm::Type *T =
1719  CGM.getTypes().ConvertType(CGM.getContext().getObjCProtoType());
1720  return CGF.Builder.CreateBitCast(protocol, llvm::PointerType::getUnqual(T));
1721 }
1722 
1723 llvm::Constant *CGObjCGNU::GenerateEmptyProtocol(
1724  const std::string &ProtocolName) {
1725  SmallVector<std::string, 0> EmptyStringVector;
1726  SmallVector<llvm::Constant*, 0> EmptyConstantVector;
1727 
1728  llvm::Constant *ProtocolList = GenerateProtocolList(EmptyStringVector);
1729  llvm::Constant *MethodList =
1730  GenerateProtocolMethodList(EmptyConstantVector, EmptyConstantVector);
1731  // Protocols are objects containing lists of the methods implemented and
1732  // protocols adopted.
1733  llvm::StructType *ProtocolTy = llvm::StructType::get(IdTy,
1734  PtrToInt8Ty,
1735  ProtocolList->getType(),
1736  MethodList->getType(),
1737  MethodList->getType(),
1738  MethodList->getType(),
1739  MethodList->getType(),
1740  nullptr);
1741  std::vector<llvm::Constant*> Elements;
1742  // The isa pointer must be set to a magic number so the runtime knows it's
1743  // the correct layout.
1744  Elements.push_back(llvm::ConstantExpr::getIntToPtr(
1745  llvm::ConstantInt::get(Int32Ty, ProtocolVersion), IdTy));
1746  Elements.push_back(MakeConstantString(ProtocolName, ".objc_protocol_name"));
1747  Elements.push_back(ProtocolList);
1748  Elements.push_back(MethodList);
1749  Elements.push_back(MethodList);
1750  Elements.push_back(MethodList);
1751  Elements.push_back(MethodList);
1752  return MakeGlobal(ProtocolTy, Elements, ".objc_protocol");
1753 }
1754 
1755 void CGObjCGNU::GenerateProtocol(const ObjCProtocolDecl *PD) {
1756  ASTContext &Context = CGM.getContext();
1757  std::string ProtocolName = PD->getNameAsString();
1758 
1759  // Use the protocol definition, if there is one.
1760  if (const ObjCProtocolDecl *Def = PD->getDefinition())
1761  PD = Def;
1762 
1763  SmallVector<std::string, 16> Protocols;
1764  for (const auto *PI : PD->protocols())
1765  Protocols.push_back(PI->getNameAsString());
1766  SmallVector<llvm::Constant*, 16> InstanceMethodNames;
1767  SmallVector<llvm::Constant*, 16> InstanceMethodTypes;
1768  SmallVector<llvm::Constant*, 16> OptionalInstanceMethodNames;
1769  SmallVector<llvm::Constant*, 16> OptionalInstanceMethodTypes;
1770  for (const auto *I : PD->instance_methods()) {
1771  std::string TypeStr;
1772  Context.getObjCEncodingForMethodDecl(I, TypeStr);
1773  if (I->getImplementationControl() == ObjCMethodDecl::Optional) {
1774  OptionalInstanceMethodNames.push_back(
1775  MakeConstantString(I->getSelector().getAsString()));
1776  OptionalInstanceMethodTypes.push_back(MakeConstantString(TypeStr));
1777  } else {
1778  InstanceMethodNames.push_back(
1779  MakeConstantString(I->getSelector().getAsString()));
1780  InstanceMethodTypes.push_back(MakeConstantString(TypeStr));
1781  }
1782  }
1783  // Collect information about class methods:
1784  SmallVector<llvm::Constant*, 16> ClassMethodNames;
1785  SmallVector<llvm::Constant*, 16> ClassMethodTypes;
1786  SmallVector<llvm::Constant*, 16> OptionalClassMethodNames;
1787  SmallVector<llvm::Constant*, 16> OptionalClassMethodTypes;
1788  for (const auto *I : PD->class_methods()) {
1789  std::string TypeStr;
1790  Context.getObjCEncodingForMethodDecl(I,TypeStr);
1791  if (I->getImplementationControl() == ObjCMethodDecl::Optional) {
1792  OptionalClassMethodNames.push_back(
1793  MakeConstantString(I->getSelector().getAsString()));
1794  OptionalClassMethodTypes.push_back(MakeConstantString(TypeStr));
1795  } else {
1796  ClassMethodNames.push_back(
1797  MakeConstantString(I->getSelector().getAsString()));
1798  ClassMethodTypes.push_back(MakeConstantString(TypeStr));
1799  }
1800  }
1801 
1802  llvm::Constant *ProtocolList = GenerateProtocolList(Protocols);
1803  llvm::Constant *InstanceMethodList =
1804  GenerateProtocolMethodList(InstanceMethodNames, InstanceMethodTypes);
1805  llvm::Constant *ClassMethodList =
1806  GenerateProtocolMethodList(ClassMethodNames, ClassMethodTypes);
1807  llvm::Constant *OptionalInstanceMethodList =
1808  GenerateProtocolMethodList(OptionalInstanceMethodNames,
1809  OptionalInstanceMethodTypes);
1810  llvm::Constant *OptionalClassMethodList =
1811  GenerateProtocolMethodList(OptionalClassMethodNames,
1812  OptionalClassMethodTypes);
1813 
1814  // Property metadata: name, attributes, isSynthesized, setter name, setter
1815  // types, getter name, getter types.
1816  // The isSynthesized value is always set to 0 in a protocol. It exists to
1817  // simplify the runtime library by allowing it to use the same data
1818  // structures for protocol metadata everywhere.
1819  llvm::StructType *PropertyMetadataTy = llvm::StructType::get(
1820  PtrToInt8Ty, Int8Ty, Int8Ty, Int8Ty, Int8Ty, PtrToInt8Ty,
1821  PtrToInt8Ty, PtrToInt8Ty, PtrToInt8Ty, nullptr);
1822  std::vector<llvm::Constant*> Properties;
1823  std::vector<llvm::Constant*> OptionalProperties;
1824 
1825  // Add all of the property methods need adding to the method list and to the
1826  // property metadata list.
1827  for (auto *property : PD->properties()) {
1828  std::vector<llvm::Constant*> Fields;
1829 
1830  Fields.push_back(MakePropertyEncodingString(property, nullptr));
1831  PushPropertyAttributes(Fields, property);
1832 
1833  if (ObjCMethodDecl *getter = property->getGetterMethodDecl()) {
1834  std::string TypeStr;
1835  Context.getObjCEncodingForMethodDecl(getter,TypeStr);
1836  llvm::Constant *TypeEncoding = MakeConstantString(TypeStr);
1837  InstanceMethodTypes.push_back(TypeEncoding);
1838  Fields.push_back(MakeConstantString(getter->getSelector().getAsString()));
1839  Fields.push_back(TypeEncoding);
1840  } else {
1841  Fields.push_back(NULLPtr);
1842  Fields.push_back(NULLPtr);
1843  }
1844  if (ObjCMethodDecl *setter = property->getSetterMethodDecl()) {
1845  std::string TypeStr;
1846  Context.getObjCEncodingForMethodDecl(setter,TypeStr);
1847  llvm::Constant *TypeEncoding = MakeConstantString(TypeStr);
1848  InstanceMethodTypes.push_back(TypeEncoding);
1849  Fields.push_back(MakeConstantString(setter->getSelector().getAsString()));
1850  Fields.push_back(TypeEncoding);
1851  } else {
1852  Fields.push_back(NULLPtr);
1853  Fields.push_back(NULLPtr);
1854  }
1855  if (property->getPropertyImplementation() == ObjCPropertyDecl::Optional) {
1856  OptionalProperties.push_back(llvm::ConstantStruct::get(PropertyMetadataTy, Fields));
1857  } else {
1858  Properties.push_back(llvm::ConstantStruct::get(PropertyMetadataTy, Fields));
1859  }
1860  }
1861  llvm::Constant *PropertyArray = llvm::ConstantArray::get(
1862  llvm::ArrayType::get(PropertyMetadataTy, Properties.size()), Properties);
1863  llvm::Constant* PropertyListInitFields[] =
1864  {llvm::ConstantInt::get(IntTy, Properties.size()), NULLPtr, PropertyArray};
1865 
1866  llvm::Constant *PropertyListInit =
1867  llvm::ConstantStruct::getAnon(PropertyListInitFields);
1868  llvm::Constant *PropertyList = new llvm::GlobalVariable(TheModule,
1869  PropertyListInit->getType(), false, llvm::GlobalValue::InternalLinkage,
1870  PropertyListInit, ".objc_property_list");
1871 
1872  llvm::Constant *OptionalPropertyArray =
1873  llvm::ConstantArray::get(llvm::ArrayType::get(PropertyMetadataTy,
1874  OptionalProperties.size()) , OptionalProperties);
1875  llvm::Constant* OptionalPropertyListInitFields[] = {
1876  llvm::ConstantInt::get(IntTy, OptionalProperties.size()), NULLPtr,
1877  OptionalPropertyArray };
1878 
1879  llvm::Constant *OptionalPropertyListInit =
1880  llvm::ConstantStruct::getAnon(OptionalPropertyListInitFields);
1881  llvm::Constant *OptionalPropertyList = new llvm::GlobalVariable(TheModule,
1882  OptionalPropertyListInit->getType(), false,
1883  llvm::GlobalValue::InternalLinkage, OptionalPropertyListInit,
1884  ".objc_property_list");
1885 
1886  // Protocols are objects containing lists of the methods implemented and
1887  // protocols adopted.
1888  llvm::StructType *ProtocolTy = llvm::StructType::get(IdTy,
1889  PtrToInt8Ty,
1890  ProtocolList->getType(),
1891  InstanceMethodList->getType(),
1892  ClassMethodList->getType(),
1893  OptionalInstanceMethodList->getType(),
1894  OptionalClassMethodList->getType(),
1895  PropertyList->getType(),
1896  OptionalPropertyList->getType(),
1897  nullptr);
1898  std::vector<llvm::Constant*> Elements;
1899  // The isa pointer must be set to a magic number so the runtime knows it's
1900  // the correct layout.
1901  Elements.push_back(llvm::ConstantExpr::getIntToPtr(
1902  llvm::ConstantInt::get(Int32Ty, ProtocolVersion), IdTy));
1903  Elements.push_back(MakeConstantString(ProtocolName, ".objc_protocol_name"));
1904  Elements.push_back(ProtocolList);
1905  Elements.push_back(InstanceMethodList);
1906  Elements.push_back(ClassMethodList);
1907  Elements.push_back(OptionalInstanceMethodList);
1908  Elements.push_back(OptionalClassMethodList);
1909  Elements.push_back(PropertyList);
1910  Elements.push_back(OptionalPropertyList);
1911  ExistingProtocols[ProtocolName] =
1912  llvm::ConstantExpr::getBitCast(MakeGlobal(ProtocolTy, Elements,
1913  ".objc_protocol"), IdTy);
1914 }
1915 void CGObjCGNU::GenerateProtocolHolderCategory() {
1916  // Collect information about instance methods
1917  SmallVector<Selector, 1> MethodSels;
1918  SmallVector<llvm::Constant*, 1> MethodTypes;
1919 
1920  std::vector<llvm::Constant*> Elements;
1921  const std::string ClassName = "__ObjC_Protocol_Holder_Ugly_Hack";
1922  const std::string CategoryName = "AnotherHack";
1923  Elements.push_back(MakeConstantString(CategoryName));
1924  Elements.push_back(MakeConstantString(ClassName));
1925  // Instance method list
1926  Elements.push_back(llvm::ConstantExpr::getBitCast(GenerateMethodList(
1927  ClassName, CategoryName, MethodSels, MethodTypes, false), PtrTy));
1928  // Class method list
1929  Elements.push_back(llvm::ConstantExpr::getBitCast(GenerateMethodList(
1930  ClassName, CategoryName, MethodSels, MethodTypes, true), PtrTy));
1931  // Protocol list
1932  llvm::ArrayType *ProtocolArrayTy = llvm::ArrayType::get(PtrTy,
1933  ExistingProtocols.size());
1934  llvm::StructType *ProtocolListTy = llvm::StructType::get(
1935  PtrTy, //Should be a recurisve pointer, but it's always NULL here.
1936  SizeTy,
1937  ProtocolArrayTy,
1938  nullptr);
1939  std::vector<llvm::Constant*> ProtocolElements;
1940  for (llvm::StringMapIterator<llvm::Constant*> iter =
1941  ExistingProtocols.begin(), endIter = ExistingProtocols.end();
1942  iter != endIter ; iter++) {
1943  llvm::Constant *Ptr = llvm::ConstantExpr::getBitCast(iter->getValue(),
1944  PtrTy);
1945  ProtocolElements.push_back(Ptr);
1946  }
1947  llvm::Constant * ProtocolArray = llvm::ConstantArray::get(ProtocolArrayTy,
1948  ProtocolElements);
1949  ProtocolElements.clear();
1950  ProtocolElements.push_back(NULLPtr);
1951  ProtocolElements.push_back(llvm::ConstantInt::get(LongTy,
1952  ExistingProtocols.size()));
1953  ProtocolElements.push_back(ProtocolArray);
1954  Elements.push_back(llvm::ConstantExpr::getBitCast(MakeGlobal(ProtocolListTy,
1955  ProtocolElements, ".objc_protocol_list"), PtrTy));
1956  Categories.push_back(llvm::ConstantExpr::getBitCast(
1957  MakeGlobal(llvm::StructType::get(PtrToInt8Ty, PtrToInt8Ty,
1958  PtrTy, PtrTy, PtrTy, nullptr), Elements), PtrTy));
1959 }
1960 
1961 /// Libobjc2 uses a bitfield representation where small(ish) bitfields are
1962 /// stored in a 64-bit value with the low bit set to 1 and the remaining 63
1963 /// bits set to their values, LSB first, while larger ones are stored in a
1964 /// structure of this / form:
1965 ///
1966 /// struct { int32_t length; int32_t values[length]; };
1967 ///
1968 /// The values in the array are stored in host-endian format, with the least
1969 /// significant bit being assumed to come first in the bitfield. Therefore, a
1970 /// bitfield with the 64th bit set will be (int64_t)&{ 2, [0, 1<<31] }, while a
1971 /// bitfield / with the 63rd bit set will be 1<<64.
1972 llvm::Constant *CGObjCGNU::MakeBitField(ArrayRef<bool> bits) {
1973  int bitCount = bits.size();
1974  int ptrBits = CGM.getDataLayout().getPointerSizeInBits();
1975  if (bitCount < ptrBits) {
1976  uint64_t val = 1;
1977  for (int i=0 ; i<bitCount ; ++i) {
1978  if (bits[i]) val |= 1ULL<<(i+1);
1979  }
1980  return llvm::ConstantInt::get(IntPtrTy, val);
1981  }
1983  int v=0;
1984  while (v < bitCount) {
1985  int32_t word = 0;
1986  for (int i=0 ; (i<32) && (v<bitCount) ; ++i) {
1987  if (bits[v]) word |= 1<<i;
1988  v++;
1989  }
1990  values.push_back(llvm::ConstantInt::get(Int32Ty, word));
1991  }
1992  llvm::ArrayType *arrayTy = llvm::ArrayType::get(Int32Ty, values.size());
1993  llvm::Constant *array = llvm::ConstantArray::get(arrayTy, values);
1994  llvm::Constant *fields[2] = {
1995  llvm::ConstantInt::get(Int32Ty, values.size()),
1996  array };
1997  llvm::Constant *GS = MakeGlobal(llvm::StructType::get(Int32Ty, arrayTy,
1998  nullptr), fields);
1999  llvm::Constant *ptr = llvm::ConstantExpr::getPtrToInt(GS, IntPtrTy);
2000  return ptr;
2001 }
2002 
2003 void CGObjCGNU::GenerateCategory(const ObjCCategoryImplDecl *OCD) {
2004  std::string ClassName = OCD->getClassInterface()->getNameAsString();
2005  std::string CategoryName = OCD->getNameAsString();
2006  // Collect information about instance methods
2007  SmallVector<Selector, 16> InstanceMethodSels;
2008  SmallVector<llvm::Constant*, 16> InstanceMethodTypes;
2009  for (const auto *I : OCD->instance_methods()) {
2010  InstanceMethodSels.push_back(I->getSelector());
2011  std::string TypeStr;
2012  CGM.getContext().getObjCEncodingForMethodDecl(I,TypeStr);
2013  InstanceMethodTypes.push_back(MakeConstantString(TypeStr));
2014  }
2015 
2016  // Collect information about class methods
2017  SmallVector<Selector, 16> ClassMethodSels;
2018  SmallVector<llvm::Constant*, 16> ClassMethodTypes;
2019  for (const auto *I : OCD->class_methods()) {
2020  ClassMethodSels.push_back(I->getSelector());
2021  std::string TypeStr;
2022  CGM.getContext().getObjCEncodingForMethodDecl(I,TypeStr);
2023  ClassMethodTypes.push_back(MakeConstantString(TypeStr));
2024  }
2025 
2026  // Collect the names of referenced protocols
2027  SmallVector<std::string, 16> Protocols;
2028  const ObjCCategoryDecl *CatDecl = OCD->getCategoryDecl();
2029  const ObjCList<ObjCProtocolDecl> &Protos = CatDecl->getReferencedProtocols();
2030  for (ObjCList<ObjCProtocolDecl>::iterator I = Protos.begin(),
2031  E = Protos.end(); I != E; ++I)
2032  Protocols.push_back((*I)->getNameAsString());
2033 
2034  std::vector<llvm::Constant*> Elements;
2035  Elements.push_back(MakeConstantString(CategoryName));
2036  Elements.push_back(MakeConstantString(ClassName));
2037  // Instance method list
2038  Elements.push_back(llvm::ConstantExpr::getBitCast(GenerateMethodList(
2039  ClassName, CategoryName, InstanceMethodSels, InstanceMethodTypes,
2040  false), PtrTy));
2041  // Class method list
2042  Elements.push_back(llvm::ConstantExpr::getBitCast(GenerateMethodList(
2043  ClassName, CategoryName, ClassMethodSels, ClassMethodTypes, true),
2044  PtrTy));
2045  // Protocol list
2046  Elements.push_back(llvm::ConstantExpr::getBitCast(
2047  GenerateProtocolList(Protocols), PtrTy));
2048  Categories.push_back(llvm::ConstantExpr::getBitCast(
2049  MakeGlobal(llvm::StructType::get(PtrToInt8Ty, PtrToInt8Ty,
2050  PtrTy, PtrTy, PtrTy, nullptr), Elements), PtrTy));
2051 }
2052 
2053 llvm::Constant *CGObjCGNU::GeneratePropertyList(const ObjCImplementationDecl *OID,
2054  SmallVectorImpl<Selector> &InstanceMethodSels,
2055  SmallVectorImpl<llvm::Constant*> &InstanceMethodTypes) {
2056  ASTContext &Context = CGM.getContext();
2057  // Property metadata: name, attributes, attributes2, padding1, padding2,
2058  // setter name, setter types, getter name, getter types.
2059  llvm::StructType *PropertyMetadataTy = llvm::StructType::get(
2060  PtrToInt8Ty, Int8Ty, Int8Ty, Int8Ty, Int8Ty, PtrToInt8Ty,
2061  PtrToInt8Ty, PtrToInt8Ty, PtrToInt8Ty, nullptr);
2062  std::vector<llvm::Constant*> Properties;
2063 
2064  // Add all of the property methods need adding to the method list and to the
2065  // property metadata list.
2066  for (auto *propertyImpl : OID->property_impls()) {
2067  std::vector<llvm::Constant*> Fields;
2068  ObjCPropertyDecl *property = propertyImpl->getPropertyDecl();
2069  bool isSynthesized = (propertyImpl->getPropertyImplementation() ==
2070  ObjCPropertyImplDecl::Synthesize);
2071  bool isDynamic = (propertyImpl->getPropertyImplementation() ==
2072  ObjCPropertyImplDecl::Dynamic);
2073 
2074  Fields.push_back(MakePropertyEncodingString(property, OID));
2075  PushPropertyAttributes(Fields, property, isSynthesized, isDynamic);
2076  if (ObjCMethodDecl *getter = property->getGetterMethodDecl()) {
2077  std::string TypeStr;
2078  Context.getObjCEncodingForMethodDecl(getter,TypeStr);
2079  llvm::Constant *TypeEncoding = MakeConstantString(TypeStr);
2080  if (isSynthesized) {
2081  InstanceMethodTypes.push_back(TypeEncoding);
2082  InstanceMethodSels.push_back(getter->getSelector());
2083  }
2084  Fields.push_back(MakeConstantString(getter->getSelector().getAsString()));
2085  Fields.push_back(TypeEncoding);
2086  } else {
2087  Fields.push_back(NULLPtr);
2088  Fields.push_back(NULLPtr);
2089  }
2090  if (ObjCMethodDecl *setter = property->getSetterMethodDecl()) {
2091  std::string TypeStr;
2092  Context.getObjCEncodingForMethodDecl(setter,TypeStr);
2093  llvm::Constant *TypeEncoding = MakeConstantString(TypeStr);
2094  if (isSynthesized) {
2095  InstanceMethodTypes.push_back(TypeEncoding);
2096  InstanceMethodSels.push_back(setter->getSelector());
2097  }
2098  Fields.push_back(MakeConstantString(setter->getSelector().getAsString()));
2099  Fields.push_back(TypeEncoding);
2100  } else {
2101  Fields.push_back(NULLPtr);
2102  Fields.push_back(NULLPtr);
2103  }
2104  Properties.push_back(llvm::ConstantStruct::get(PropertyMetadataTy, Fields));
2105  }
2106  llvm::ArrayType *PropertyArrayTy =
2107  llvm::ArrayType::get(PropertyMetadataTy, Properties.size());
2108  llvm::Constant *PropertyArray = llvm::ConstantArray::get(PropertyArrayTy,
2109  Properties);
2110  llvm::Constant* PropertyListInitFields[] =
2111  {llvm::ConstantInt::get(IntTy, Properties.size()), NULLPtr, PropertyArray};
2112 
2113  llvm::Constant *PropertyListInit =
2114  llvm::ConstantStruct::getAnon(PropertyListInitFields);
2115  return new llvm::GlobalVariable(TheModule, PropertyListInit->getType(), false,
2116  llvm::GlobalValue::InternalLinkage, PropertyListInit,
2117  ".objc_property_list");
2118 }
2119 
2120 void CGObjCGNU::RegisterAlias(const ObjCCompatibleAliasDecl *OAD) {
2121  // Get the class declaration for which the alias is specified.
2122  ObjCInterfaceDecl *ClassDecl =
2123  const_cast<ObjCInterfaceDecl *>(OAD->getClassInterface());
2124  ClassAliases.emplace_back(ClassDecl->getNameAsString(),
2125  OAD->getNameAsString());
2126 }
2127 
2128 void CGObjCGNU::GenerateClass(const ObjCImplementationDecl *OID) {
2129  ASTContext &Context = CGM.getContext();
2130 
2131  // Get the superclass name.
2132  const ObjCInterfaceDecl * SuperClassDecl =
2133  OID->getClassInterface()->getSuperClass();
2134  std::string SuperClassName;
2135  if (SuperClassDecl) {
2136  SuperClassName = SuperClassDecl->getNameAsString();
2137  EmitClassRef(SuperClassName);
2138  }
2139 
2140  // Get the class name
2141  ObjCInterfaceDecl *ClassDecl =
2142  const_cast<ObjCInterfaceDecl *>(OID->getClassInterface());
2143  std::string ClassName = ClassDecl->getNameAsString();
2144  // Emit the symbol that is used to generate linker errors if this class is
2145  // referenced in other modules but not declared.
2146  std::string classSymbolName = "__objc_class_name_" + ClassName;
2147  if (llvm::GlobalVariable *symbol =
2148  TheModule.getGlobalVariable(classSymbolName)) {
2149  symbol->setInitializer(llvm::ConstantInt::get(LongTy, 0));
2150  } else {
2151  new llvm::GlobalVariable(TheModule, LongTy, false,
2152  llvm::GlobalValue::ExternalLinkage, llvm::ConstantInt::get(LongTy, 0),
2153  classSymbolName);
2154  }
2155 
2156  // Get the size of instances.
2157  int instanceSize =
2159 
2160  // Collect information about instance variables.
2164 
2165  std::vector<llvm::Constant*> IvarOffsetValues;
2166  SmallVector<bool, 16> WeakIvars;
2167  SmallVector<bool, 16> StrongIvars;
2168 
2169  int superInstanceSize = !SuperClassDecl ? 0 :
2170  Context.getASTObjCInterfaceLayout(SuperClassDecl).getSize().getQuantity();
2171  // For non-fragile ivars, set the instance size to 0 - {the size of just this
2172  // class}. The runtime will then set this to the correct value on load.
2173  if (CGM.getLangOpts().ObjCRuntime.isNonFragile()) {
2174  instanceSize = 0 - (instanceSize - superInstanceSize);
2175  }
2176 
2177  for (const ObjCIvarDecl *IVD = ClassDecl->all_declared_ivar_begin(); IVD;
2178  IVD = IVD->getNextIvar()) {
2179  // Store the name
2180  IvarNames.push_back(MakeConstantString(IVD->getNameAsString()));
2181  // Get the type encoding for this ivar
2182  std::string TypeStr;
2183  Context.getObjCEncodingForType(IVD->getType(), TypeStr);
2184  IvarTypes.push_back(MakeConstantString(TypeStr));
2185  // Get the offset
2186  uint64_t BaseOffset = ComputeIvarBaseOffset(CGM, OID, IVD);
2187  uint64_t Offset = BaseOffset;
2188  if (CGM.getLangOpts().ObjCRuntime.isNonFragile()) {
2189  Offset = BaseOffset - superInstanceSize;
2190  }
2191  llvm::Constant *OffsetValue = llvm::ConstantInt::get(IntTy, Offset);
2192  // Create the direct offset value
2193  std::string OffsetName = "__objc_ivar_offset_value_" + ClassName +"." +
2194  IVD->getNameAsString();
2195  llvm::GlobalVariable *OffsetVar = TheModule.getGlobalVariable(OffsetName);
2196  if (OffsetVar) {
2197  OffsetVar->setInitializer(OffsetValue);
2198  // If this is the real definition, change its linkage type so that
2199  // different modules will use this one, rather than their private
2200  // copy.
2201  OffsetVar->setLinkage(llvm::GlobalValue::ExternalLinkage);
2202  } else
2203  OffsetVar = new llvm::GlobalVariable(TheModule, IntTy,
2205  OffsetValue,
2206  "__objc_ivar_offset_value_" + ClassName +"." +
2207  IVD->getNameAsString());
2208  IvarOffsets.push_back(OffsetValue);
2209  IvarOffsetValues.push_back(OffsetVar);
2210  Qualifiers::ObjCLifetime lt = IVD->getType().getQualifiers().getObjCLifetime();
2211  switch (lt) {
2212  case Qualifiers::OCL_Strong:
2213  StrongIvars.push_back(true);
2214  WeakIvars.push_back(false);
2215  break;
2216  case Qualifiers::OCL_Weak:
2217  StrongIvars.push_back(false);
2218  WeakIvars.push_back(true);
2219  break;
2220  default:
2221  StrongIvars.push_back(false);
2222  WeakIvars.push_back(false);
2223  }
2224  }
2225  llvm::Constant *StrongIvarBitmap = MakeBitField(StrongIvars);
2226  llvm::Constant *WeakIvarBitmap = MakeBitField(WeakIvars);
2227  llvm::GlobalVariable *IvarOffsetArray =
2228  MakeGlobalArray(PtrToIntTy, IvarOffsetValues, ".ivar.offsets");
2229 
2230 
2231  // Collect information about instance methods
2232  SmallVector<Selector, 16> InstanceMethodSels;
2233  SmallVector<llvm::Constant*, 16> InstanceMethodTypes;
2234  for (const auto *I : OID->instance_methods()) {
2235  InstanceMethodSels.push_back(I->getSelector());
2236  std::string TypeStr;
2237  Context.getObjCEncodingForMethodDecl(I,TypeStr);
2238  InstanceMethodTypes.push_back(MakeConstantString(TypeStr));
2239  }
2240 
2241  llvm::Constant *Properties = GeneratePropertyList(OID, InstanceMethodSels,
2242  InstanceMethodTypes);
2243 
2244 
2245  // Collect information about class methods
2246  SmallVector<Selector, 16> ClassMethodSels;
2247  SmallVector<llvm::Constant*, 16> ClassMethodTypes;
2248  for (const auto *I : OID->class_methods()) {
2249  ClassMethodSels.push_back(I->getSelector());
2250  std::string TypeStr;
2251  Context.getObjCEncodingForMethodDecl(I,TypeStr);
2252  ClassMethodTypes.push_back(MakeConstantString(TypeStr));
2253  }
2254  // Collect the names of referenced protocols
2255  SmallVector<std::string, 16> Protocols;
2256  for (const auto *I : ClassDecl->protocols())
2257  Protocols.push_back(I->getNameAsString());
2258 
2259  // Get the superclass pointer.
2260  llvm::Constant *SuperClass;
2261  if (!SuperClassName.empty()) {
2262  SuperClass = MakeConstantString(SuperClassName, ".super_class_name");
2263  } else {
2264  SuperClass = llvm::ConstantPointerNull::get(PtrToInt8Ty);
2265  }
2266  // Empty vector used to construct empty method lists
2268  // Generate the method and instance variable lists
2269  llvm::Constant *MethodList = GenerateMethodList(ClassName, "",
2270  InstanceMethodSels, InstanceMethodTypes, false);
2271  llvm::Constant *ClassMethodList = GenerateMethodList(ClassName, "",
2272  ClassMethodSels, ClassMethodTypes, true);
2273  llvm::Constant *IvarList = GenerateIvarList(IvarNames, IvarTypes,
2274  IvarOffsets);
2275  // Irrespective of whether we are compiling for a fragile or non-fragile ABI,
2276  // we emit a symbol containing the offset for each ivar in the class. This
2277  // allows code compiled for the non-Fragile ABI to inherit from code compiled
2278  // for the legacy ABI, without causing problems. The converse is also
2279  // possible, but causes all ivar accesses to be fragile.
2280 
2281  // Offset pointer for getting at the correct field in the ivar list when
2282  // setting up the alias. These are: The base address for the global, the
2283  // ivar array (second field), the ivar in this list (set for each ivar), and
2284  // the offset (third field in ivar structure)
2285  llvm::Type *IndexTy = Int32Ty;
2286  llvm::Constant *offsetPointerIndexes[] = {Zeros[0],
2287  llvm::ConstantInt::get(IndexTy, 1), nullptr,
2288  llvm::ConstantInt::get(IndexTy, 2) };
2289 
2290  unsigned ivarIndex = 0;
2291  for (const ObjCIvarDecl *IVD = ClassDecl->all_declared_ivar_begin(); IVD;
2292  IVD = IVD->getNextIvar()) {
2293  const std::string Name = "__objc_ivar_offset_" + ClassName + '.'
2294  + IVD->getNameAsString();
2295  offsetPointerIndexes[2] = llvm::ConstantInt::get(IndexTy, ivarIndex);
2296  // Get the correct ivar field
2297  llvm::Constant *offsetValue = llvm::ConstantExpr::getGetElementPtr(
2298  cast<llvm::GlobalVariable>(IvarList)->getValueType(), IvarList,
2299  offsetPointerIndexes);
2300  // Get the existing variable, if one exists.
2301  llvm::GlobalVariable *offset = TheModule.getNamedGlobal(Name);
2302  if (offset) {
2303  offset->setInitializer(offsetValue);
2304  // If this is the real definition, change its linkage type so that
2305  // different modules will use this one, rather than their private
2306  // copy.
2307  offset->setLinkage(llvm::GlobalValue::ExternalLinkage);
2308  } else {
2309  // Add a new alias if there isn't one already.
2310  offset = new llvm::GlobalVariable(TheModule, offsetValue->getType(),
2311  false, llvm::GlobalValue::ExternalLinkage, offsetValue, Name);
2312  (void) offset; // Silence dead store warning.
2313  }
2314  ++ivarIndex;
2315  }
2316  llvm::Constant *ZeroPtr = llvm::ConstantInt::get(IntPtrTy, 0);
2317  //Generate metaclass for class methods
2318  llvm::Constant *MetaClassStruct = GenerateClassStructure(NULLPtr,
2319  NULLPtr, 0x12L, ClassName.c_str(), nullptr, Zeros[0], GenerateIvarList(
2320  empty, empty, empty), ClassMethodList, NULLPtr,
2321  NULLPtr, NULLPtr, ZeroPtr, ZeroPtr, true);
2322 
2323  // Generate the class structure
2324  llvm::Constant *ClassStruct =
2325  GenerateClassStructure(MetaClassStruct, SuperClass, 0x11L,
2326  ClassName.c_str(), nullptr,
2327  llvm::ConstantInt::get(LongTy, instanceSize), IvarList,
2328  MethodList, GenerateProtocolList(Protocols), IvarOffsetArray,
2329  Properties, StrongIvarBitmap, WeakIvarBitmap);
2330 
2331  // Resolve the class aliases, if they exist.
2332  if (ClassPtrAlias) {
2333  ClassPtrAlias->replaceAllUsesWith(
2334  llvm::ConstantExpr::getBitCast(ClassStruct, IdTy));
2335  ClassPtrAlias->eraseFromParent();
2336  ClassPtrAlias = nullptr;
2337  }
2338  if (MetaClassPtrAlias) {
2339  MetaClassPtrAlias->replaceAllUsesWith(
2340  llvm::ConstantExpr::getBitCast(MetaClassStruct, IdTy));
2341  MetaClassPtrAlias->eraseFromParent();
2342  MetaClassPtrAlias = nullptr;
2343  }
2344 
2345  // Add class structure to list to be added to the symtab later
2346  ClassStruct = llvm::ConstantExpr::getBitCast(ClassStruct, PtrToInt8Ty);
2347  Classes.push_back(ClassStruct);
2348 }
2349 
2350 
2351 llvm::Function *CGObjCGNU::ModuleInitFunction() {
2352  // Only emit an ObjC load function if no Objective-C stuff has been called
2353  if (Classes.empty() && Categories.empty() && ConstantStrings.empty() &&
2354  ExistingProtocols.empty() && SelectorTable.empty())
2355  return nullptr;
2356 
2357  // Add all referenced protocols to a category.
2358  GenerateProtocolHolderCategory();
2359 
2360  llvm::StructType *SelStructTy = dyn_cast<llvm::StructType>(
2361  SelectorTy->getElementType());
2362  llvm::Type *SelStructPtrTy = SelectorTy;
2363  if (!SelStructTy) {
2364  SelStructTy = llvm::StructType::get(PtrToInt8Ty, PtrToInt8Ty, nullptr);
2365  SelStructPtrTy = llvm::PointerType::getUnqual(SelStructTy);
2366  }
2367 
2368  std::vector<llvm::Constant*> Elements;
2369  llvm::Constant *Statics = NULLPtr;
2370  // Generate statics list:
2371  if (!ConstantStrings.empty()) {
2372  llvm::ArrayType *StaticsArrayTy = llvm::ArrayType::get(PtrToInt8Ty,
2373  ConstantStrings.size() + 1);
2374  ConstantStrings.push_back(NULLPtr);
2375 
2376  StringRef StringClass = CGM.getLangOpts().ObjCConstantStringClass;
2377 
2378  if (StringClass.empty()) StringClass = "NXConstantString";
2379 
2380  Elements.push_back(MakeConstantString(StringClass,
2381  ".objc_static_class_name"));
2382  Elements.push_back(llvm::ConstantArray::get(StaticsArrayTy,
2383  ConstantStrings));
2384  llvm::StructType *StaticsListTy =
2385  llvm::StructType::get(PtrToInt8Ty, StaticsArrayTy, nullptr);
2386  llvm::Type *StaticsListPtrTy =
2387  llvm::PointerType::getUnqual(StaticsListTy);
2388  Statics = MakeGlobal(StaticsListTy, Elements, ".objc_statics");
2389  llvm::ArrayType *StaticsListArrayTy =
2390  llvm::ArrayType::get(StaticsListPtrTy, 2);
2391  Elements.clear();
2392  Elements.push_back(Statics);
2393  Elements.push_back(llvm::Constant::getNullValue(StaticsListPtrTy));
2394  Statics = MakeGlobal(StaticsListArrayTy, Elements, ".objc_statics_ptr");
2395  Statics = llvm::ConstantExpr::getBitCast(Statics, PtrTy);
2396  }
2397  // Array of classes, categories, and constant objects
2398  llvm::ArrayType *ClassListTy = llvm::ArrayType::get(PtrToInt8Ty,
2399  Classes.size() + Categories.size() + 2);
2400  llvm::StructType *SymTabTy = llvm::StructType::get(LongTy, SelStructPtrTy,
2401  llvm::Type::getInt16Ty(VMContext),
2402  llvm::Type::getInt16Ty(VMContext),
2403  ClassListTy, nullptr);
2404 
2405  Elements.clear();
2406  // Pointer to an array of selectors used in this module.
2407  std::vector<llvm::Constant*> Selectors;
2408  std::vector<llvm::GlobalAlias*> SelectorAliases;
2409  for (SelectorMap::iterator iter = SelectorTable.begin(),
2410  iterEnd = SelectorTable.end(); iter != iterEnd ; ++iter) {
2411 
2412  std::string SelNameStr = iter->first.getAsString();
2413  llvm::Constant *SelName = ExportUniqueString(SelNameStr, ".objc_sel_name");
2414 
2415  SmallVectorImpl<TypedSelector> &Types = iter->second;
2416  for (SmallVectorImpl<TypedSelector>::iterator i = Types.begin(),
2417  e = Types.end() ; i!=e ; i++) {
2418 
2419  llvm::Constant *SelectorTypeEncoding = NULLPtr;
2420  if (!i->first.empty())
2421  SelectorTypeEncoding = MakeConstantString(i->first, ".objc_sel_types");
2422 
2423  Elements.push_back(SelName);
2424  Elements.push_back(SelectorTypeEncoding);
2425  Selectors.push_back(llvm::ConstantStruct::get(SelStructTy, Elements));
2426  Elements.clear();
2427 
2428  // Store the selector alias for later replacement
2429  SelectorAliases.push_back(i->second);
2430  }
2431  }
2432  unsigned SelectorCount = Selectors.size();
2433  // NULL-terminate the selector list. This should not actually be required,
2434  // because the selector list has a length field. Unfortunately, the GCC
2435  // runtime decides to ignore the length field and expects a NULL terminator,
2436  // and GCC cooperates with this by always setting the length to 0.
2437  Elements.push_back(NULLPtr);
2438  Elements.push_back(NULLPtr);
2439  Selectors.push_back(llvm::ConstantStruct::get(SelStructTy, Elements));
2440  Elements.clear();
2441 
2442  // Number of static selectors
2443  Elements.push_back(llvm::ConstantInt::get(LongTy, SelectorCount));
2444  llvm::GlobalVariable *SelectorList =
2445  MakeGlobalArray(SelStructTy, Selectors, ".objc_selector_list");
2446  Elements.push_back(llvm::ConstantExpr::getBitCast(SelectorList,
2447  SelStructPtrTy));
2448 
2449  // Now that all of the static selectors exist, create pointers to them.
2450  for (unsigned int i=0 ; i<SelectorCount ; i++) {
2451 
2452  llvm::Constant *Idxs[] = {Zeros[0],
2453  llvm::ConstantInt::get(Int32Ty, i), Zeros[0]};
2454  // FIXME: We're generating redundant loads and stores here!
2455  llvm::Constant *SelPtr = llvm::ConstantExpr::getGetElementPtr(
2456  SelectorList->getValueType(), SelectorList, makeArrayRef(Idxs, 2));
2457  // If selectors are defined as an opaque type, cast the pointer to this
2458  // type.
2459  SelPtr = llvm::ConstantExpr::getBitCast(SelPtr, SelectorTy);
2460  SelectorAliases[i]->replaceAllUsesWith(SelPtr);
2461  SelectorAliases[i]->eraseFromParent();
2462  }
2463 
2464  // Number of classes defined.
2465  Elements.push_back(llvm::ConstantInt::get(llvm::Type::getInt16Ty(VMContext),
2466  Classes.size()));
2467  // Number of categories defined
2468  Elements.push_back(llvm::ConstantInt::get(llvm::Type::getInt16Ty(VMContext),
2469  Categories.size()));
2470  // Create an array of classes, then categories, then static object instances
2471  Classes.insert(Classes.end(), Categories.begin(), Categories.end());
2472  // NULL-terminated list of static object instances (mainly constant strings)
2473  Classes.push_back(Statics);
2474  Classes.push_back(NULLPtr);
2475  llvm::Constant *ClassList = llvm::ConstantArray::get(ClassListTy, Classes);
2476  Elements.push_back(ClassList);
2477  // Construct the symbol table
2478  llvm::Constant *SymTab= MakeGlobal(SymTabTy, Elements);
2479 
2480  // The symbol table is contained in a module which has some version-checking
2481  // constants
2482  llvm::StructType * ModuleTy = llvm::StructType::get(LongTy, LongTy,
2483  PtrToInt8Ty, llvm::PointerType::getUnqual(SymTabTy),
2484  (RuntimeVersion >= 10) ? IntTy : nullptr, nullptr);
2485  Elements.clear();
2486  // Runtime version, used for ABI compatibility checking.
2487  Elements.push_back(llvm::ConstantInt::get(LongTy, RuntimeVersion));
2488  // sizeof(ModuleTy)
2489  llvm::DataLayout td(&TheModule);
2490  Elements.push_back(
2491  llvm::ConstantInt::get(LongTy,
2492  td.getTypeSizeInBits(ModuleTy) /
2493  CGM.getContext().getCharWidth()));
2494 
2495  // The path to the source file where this module was declared
2496  SourceManager &SM = CGM.getContext().getSourceManager();
2497  const FileEntry *mainFile = SM.getFileEntryForID(SM.getMainFileID());
2498  std::string path =
2499  std::string(mainFile->getDir()->getName()) + '/' + mainFile->getName();
2500  Elements.push_back(MakeConstantString(path, ".objc_source_file_name"));
2501  Elements.push_back(SymTab);
2502 
2503  if (RuntimeVersion >= 10)
2504  switch (CGM.getLangOpts().getGC()) {
2505  case LangOptions::GCOnly:
2506  Elements.push_back(llvm::ConstantInt::get(IntTy, 2));
2507  break;
2508  case LangOptions::NonGC:
2509  if (CGM.getLangOpts().ObjCAutoRefCount)
2510  Elements.push_back(llvm::ConstantInt::get(IntTy, 1));
2511  else
2512  Elements.push_back(llvm::ConstantInt::get(IntTy, 0));
2513  break;
2514  case LangOptions::HybridGC:
2515  Elements.push_back(llvm::ConstantInt::get(IntTy, 1));
2516  break;
2517  }
2518 
2519  llvm::Value *Module = MakeGlobal(ModuleTy, Elements);
2520 
2521  // Create the load function calling the runtime entry point with the module
2522  // structure
2523  llvm::Function * LoadFunction = llvm::Function::Create(
2524  llvm::FunctionType::get(llvm::Type::getVoidTy(VMContext), false),
2525  llvm::GlobalValue::InternalLinkage, ".objc_load_function",
2526  &TheModule);
2527  llvm::BasicBlock *EntryBB =
2528  llvm::BasicBlock::Create(VMContext, "entry", LoadFunction);
2529  CGBuilderTy Builder(VMContext);
2530  Builder.SetInsertPoint(EntryBB);
2531 
2532  llvm::FunctionType *FT =
2533  llvm::FunctionType::get(Builder.getVoidTy(),
2534  llvm::PointerType::getUnqual(ModuleTy), true);
2535  llvm::Value *Register = CGM.CreateRuntimeFunction(FT, "__objc_exec_class");
2536  Builder.CreateCall(Register, Module);
2537 
2538  if (!ClassAliases.empty()) {
2539  llvm::Type *ArgTypes[2] = {PtrTy, PtrToInt8Ty};
2540  llvm::FunctionType *RegisterAliasTy =
2541  llvm::FunctionType::get(Builder.getVoidTy(),
2542  ArgTypes, false);
2543  llvm::Function *RegisterAlias = llvm::Function::Create(
2544  RegisterAliasTy,
2545  llvm::GlobalValue::ExternalWeakLinkage, "class_registerAlias_np",
2546  &TheModule);
2547  llvm::BasicBlock *AliasBB =
2548  llvm::BasicBlock::Create(VMContext, "alias", LoadFunction);
2549  llvm::BasicBlock *NoAliasBB =
2550  llvm::BasicBlock::Create(VMContext, "no_alias", LoadFunction);
2551 
2552  // Branch based on whether the runtime provided class_registerAlias_np()
2553  llvm::Value *HasRegisterAlias = Builder.CreateICmpNE(RegisterAlias,
2554  llvm::Constant::getNullValue(RegisterAlias->getType()));
2555  Builder.CreateCondBr(HasRegisterAlias, AliasBB, NoAliasBB);
2556 
2557  // The true branch (has alias registration function):
2558  Builder.SetInsertPoint(AliasBB);
2559  // Emit alias registration calls:
2560  for (std::vector<ClassAliasPair>::iterator iter = ClassAliases.begin();
2561  iter != ClassAliases.end(); ++iter) {
2562  llvm::Constant *TheClass =
2563  TheModule.getGlobalVariable(("_OBJC_CLASS_" + iter->first).c_str(),
2564  true);
2565  if (TheClass) {
2566  TheClass = llvm::ConstantExpr::getBitCast(TheClass, PtrTy);
2567  Builder.CreateCall(RegisterAlias,
2568  {TheClass, MakeConstantString(iter->second)});
2569  }
2570  }
2571  // Jump to end:
2572  Builder.CreateBr(NoAliasBB);
2573 
2574  // Missing alias registration function, just return from the function:
2575  Builder.SetInsertPoint(NoAliasBB);
2576  }
2577  Builder.CreateRetVoid();
2578 
2579  return LoadFunction;
2580 }
2581 
2582 llvm::Function *CGObjCGNU::GenerateMethod(const ObjCMethodDecl *OMD,
2583  const ObjCContainerDecl *CD) {
2584  const ObjCCategoryImplDecl *OCD =
2585  dyn_cast<ObjCCategoryImplDecl>(OMD->getDeclContext());
2586  StringRef CategoryName = OCD ? OCD->getName() : "";
2587  StringRef ClassName = CD->getName();
2588  Selector MethodName = OMD->getSelector();
2589  bool isClassMethod = !OMD->isInstanceMethod();
2590 
2591  CodeGenTypes &Types = CGM.getTypes();
2592  llvm::FunctionType *MethodTy =
2594  std::string FunctionName = SymbolNameForMethod(ClassName, CategoryName,
2595  MethodName, isClassMethod);
2596 
2597  llvm::Function *Method
2598  = llvm::Function::Create(MethodTy,
2600  FunctionName,
2601  &TheModule);
2602  return Method;
2603 }
2604 
2605 llvm::Constant *CGObjCGNU::GetPropertyGetFunction() {
2606  return GetPropertyFn;
2607 }
2608 
2609 llvm::Constant *CGObjCGNU::GetPropertySetFunction() {
2610  return SetPropertyFn;
2611 }
2612 
2613 llvm::Constant *CGObjCGNU::GetOptimizedPropertySetFunction(bool atomic,
2614  bool copy) {
2615  return nullptr;
2616 }
2617 
2618 llvm::Constant *CGObjCGNU::GetGetStructFunction() {
2619  return GetStructPropertyFn;
2620 }
2621 llvm::Constant *CGObjCGNU::GetSetStructFunction() {
2622  return SetStructPropertyFn;
2623 }
2624 llvm::Constant *CGObjCGNU::GetCppAtomicObjectGetFunction() {
2625  return nullptr;
2626 }
2627 llvm::Constant *CGObjCGNU::GetCppAtomicObjectSetFunction() {
2628  return nullptr;
2629 }
2630 
2631 llvm::Constant *CGObjCGNU::EnumerationMutationFunction() {
2632  return EnumerationMutationFn;
2633 }
2634 
2635 void CGObjCGNU::EmitSynchronizedStmt(CodeGenFunction &CGF,
2636  const ObjCAtSynchronizedStmt &S) {
2637  EmitAtSynchronizedStmt(CGF, S, SyncEnterFn, SyncExitFn);
2638 }
2639 
2640 
2641 void CGObjCGNU::EmitTryStmt(CodeGenFunction &CGF,
2642  const ObjCAtTryStmt &S) {
2643  // Unlike the Apple non-fragile runtimes, which also uses
2644  // unwind-based zero cost exceptions, the GNU Objective C runtime's
2645  // EH support isn't a veneer over C++ EH. Instead, exception
2646  // objects are created by objc_exception_throw and destroyed by
2647  // the personality function; this avoids the need for bracketing
2648  // catch handlers with calls to __blah_begin_catch/__blah_end_catch
2649  // (or even _Unwind_DeleteException), but probably doesn't
2650  // interoperate very well with foreign exceptions.
2651  //
2652  // In Objective-C++ mode, we actually emit something equivalent to the C++
2653  // exception handler.
2654  EmitTryCatchStmt(CGF, S, EnterCatchFn, ExitCatchFn, ExceptionReThrowFn);
2655  return ;
2656 }
2657 
2658 void CGObjCGNU::EmitThrowStmt(CodeGenFunction &CGF,
2659  const ObjCAtThrowStmt &S,
2660  bool ClearInsertionPoint) {
2661  llvm::Value *ExceptionAsObject;
2662 
2663  if (const Expr *ThrowExpr = S.getThrowExpr()) {
2664  llvm::Value *Exception = CGF.EmitObjCThrowOperand(ThrowExpr);
2665  ExceptionAsObject = Exception;
2666  } else {
2667  assert((!CGF.ObjCEHValueStack.empty() && CGF.ObjCEHValueStack.back()) &&
2668  "Unexpected rethrow outside @catch block.");
2669  ExceptionAsObject = CGF.ObjCEHValueStack.back();
2670  }
2671  ExceptionAsObject = CGF.Builder.CreateBitCast(ExceptionAsObject, IdTy);
2672  llvm::CallSite Throw =
2673  CGF.EmitRuntimeCallOrInvoke(ExceptionThrowFn, ExceptionAsObject);
2674  Throw.setDoesNotReturn();
2675  CGF.Builder.CreateUnreachable();
2676  if (ClearInsertionPoint)
2677  CGF.Builder.ClearInsertionPoint();
2678 }
2679 
2680 llvm::Value * CGObjCGNU::EmitObjCWeakRead(CodeGenFunction &CGF,
2681  llvm::Value *AddrWeakObj) {
2682  CGBuilderTy &B = CGF.Builder;
2683  AddrWeakObj = EnforceType(B, AddrWeakObj, PtrToIdTy);
2684  return B.CreateCall(WeakReadFn.getType(), WeakReadFn, AddrWeakObj);
2685 }
2686 
2687 void CGObjCGNU::EmitObjCWeakAssign(CodeGenFunction &CGF,
2688  llvm::Value *src, llvm::Value *dst) {
2689  CGBuilderTy &B = CGF.Builder;
2690  src = EnforceType(B, src, IdTy);
2691  dst = EnforceType(B, dst, PtrToIdTy);
2692  B.CreateCall(WeakAssignFn.getType(), WeakAssignFn, {src, dst});
2693 }
2694 
2695 void CGObjCGNU::EmitObjCGlobalAssign(CodeGenFunction &CGF,
2696  llvm::Value *src, llvm::Value *dst,
2697  bool threadlocal) {
2698  CGBuilderTy &B = CGF.Builder;
2699  src = EnforceType(B, src, IdTy);
2700  dst = EnforceType(B, dst, PtrToIdTy);
2701  // FIXME. Add threadloca assign API
2702  assert(!threadlocal && "EmitObjCGlobalAssign - Threal Local API NYI");
2703  B.CreateCall(GlobalAssignFn.getType(), GlobalAssignFn, {src, dst});
2704 }
2705 
2706 void CGObjCGNU::EmitObjCIvarAssign(CodeGenFunction &CGF,
2707  llvm::Value *src, llvm::Value *dst,
2708  llvm::Value *ivarOffset) {
2709  CGBuilderTy &B = CGF.Builder;
2710  src = EnforceType(B, src, IdTy);
2711  dst = EnforceType(B, dst, IdTy);
2712  B.CreateCall(IvarAssignFn.getType(), IvarAssignFn, {src, dst, ivarOffset});
2713 }
2714 
2715 void CGObjCGNU::EmitObjCStrongCastAssign(CodeGenFunction &CGF,
2716  llvm::Value *src, llvm::Value *dst) {
2717  CGBuilderTy &B = CGF.Builder;
2718  src = EnforceType(B, src, IdTy);
2719  dst = EnforceType(B, dst, PtrToIdTy);
2720  B.CreateCall(StrongCastAssignFn.getType(), StrongCastAssignFn, {src, dst});
2721 }
2722 
2723 void CGObjCGNU::EmitGCMemmoveCollectable(CodeGenFunction &CGF,
2724  llvm::Value *DestPtr,
2725  llvm::Value *SrcPtr,
2726  llvm::Value *Size) {
2727  CGBuilderTy &B = CGF.Builder;
2728  DestPtr = EnforceType(B, DestPtr, PtrTy);
2729  SrcPtr = EnforceType(B, SrcPtr, PtrTy);
2730 
2731  B.CreateCall(MemMoveFn.getType(), MemMoveFn, {DestPtr, SrcPtr, Size});
2732 }
2733 
2734 llvm::GlobalVariable *CGObjCGNU::ObjCIvarOffsetVariable(
2735  const ObjCInterfaceDecl *ID,
2736  const ObjCIvarDecl *Ivar) {
2737  const std::string Name = "__objc_ivar_offset_" + ID->getNameAsString()
2738  + '.' + Ivar->getNameAsString();
2739  // Emit the variable and initialize it with what we think the correct value
2740  // is. This allows code compiled with non-fragile ivars to work correctly
2741  // when linked against code which isn't (most of the time).
2742  llvm::GlobalVariable *IvarOffsetPointer = TheModule.getNamedGlobal(Name);
2743  if (!IvarOffsetPointer) {
2744  // This will cause a run-time crash if we accidentally use it. A value of
2745  // 0 would seem more sensible, but will silently overwrite the isa pointer
2746  // causing a great deal of confusion.
2747  uint64_t Offset = -1;
2748  // We can't call ComputeIvarBaseOffset() here if we have the
2749  // implementation, because it will create an invalid ASTRecordLayout object
2750  // that we are then stuck with forever, so we only initialize the ivar
2751  // offset variable with a guess if we only have the interface. The
2752  // initializer will be reset later anyway, when we are generating the class
2753  // description.
2754  if (!CGM.getContext().getObjCImplementation(
2755  const_cast<ObjCInterfaceDecl *>(ID)))
2756  Offset = ComputeIvarBaseOffset(CGM, ID, Ivar);
2757 
2758  llvm::ConstantInt *OffsetGuess = llvm::ConstantInt::get(Int32Ty, Offset,
2759  /*isSigned*/true);
2760  // Don't emit the guess in non-PIC code because the linker will not be able
2761  // to replace it with the real version for a library. In non-PIC code you
2762  // must compile with the fragile ABI if you want to use ivars from a
2763  // GCC-compiled class.
2764  if (CGM.getLangOpts().PICLevel || CGM.getLangOpts().PIELevel) {
2765  llvm::GlobalVariable *IvarOffsetGV = new llvm::GlobalVariable(TheModule,
2766  Int32Ty, false,
2767  llvm::GlobalValue::PrivateLinkage, OffsetGuess, Name+".guess");
2768  IvarOffsetPointer = new llvm::GlobalVariable(TheModule,
2769  IvarOffsetGV->getType(), false, llvm::GlobalValue::LinkOnceAnyLinkage,
2770  IvarOffsetGV, Name);
2771  } else {
2772  IvarOffsetPointer = new llvm::GlobalVariable(TheModule,
2773  llvm::Type::getInt32PtrTy(VMContext), false,
2774  llvm::GlobalValue::ExternalLinkage, nullptr, Name);
2775  }
2776  }
2777  return IvarOffsetPointer;
2778 }
2779 
2780 LValue CGObjCGNU::EmitObjCValueForIvar(CodeGenFunction &CGF,
2781  QualType ObjectTy,
2782  llvm::Value *BaseValue,
2783  const ObjCIvarDecl *Ivar,
2784  unsigned CVRQualifiers) {
2785  const ObjCInterfaceDecl *ID =
2786  ObjectTy->getAs<ObjCObjectType>()->getInterface();
2787  return EmitValueForIvarAtOffset(CGF, ID, BaseValue, Ivar, CVRQualifiers,
2788  EmitIvarOffset(CGF, ID, Ivar));
2789 }
2790 
2792  const ObjCInterfaceDecl *OID,
2793  const ObjCIvarDecl *OIVD) {
2794  for (const ObjCIvarDecl *next = OID->all_declared_ivar_begin(); next;
2795  next = next->getNextIvar()) {
2796  if (OIVD == next)
2797  return OID;
2798  }
2799 
2800  // Otherwise check in the super class.
2801  if (const ObjCInterfaceDecl *Super = OID->getSuperClass())
2802  return FindIvarInterface(Context, Super, OIVD);
2803 
2804  return nullptr;
2805 }
2806 
2807 llvm::Value *CGObjCGNU::EmitIvarOffset(CodeGenFunction &CGF,
2808  const ObjCInterfaceDecl *Interface,
2809  const ObjCIvarDecl *Ivar) {
2810  if (CGM.getLangOpts().ObjCRuntime.isNonFragile()) {
2811  Interface = FindIvarInterface(CGM.getContext(), Interface, Ivar);
2812  if (RuntimeVersion < 10)
2813  return CGF.Builder.CreateZExtOrBitCast(
2814  CGF.Builder.CreateLoad(CGF.Builder.CreateLoad(
2815  ObjCIvarOffsetVariable(Interface, Ivar), false, "ivar")),
2816  PtrDiffTy);
2817  std::string name = "__objc_ivar_offset_value_" +
2818  Interface->getNameAsString() +"." + Ivar->getNameAsString();
2819  llvm::Value *Offset = TheModule.getGlobalVariable(name);
2820  if (!Offset)
2821  Offset = new llvm::GlobalVariable(TheModule, IntTy,
2822  false, llvm::GlobalValue::LinkOnceAnyLinkage,
2823  llvm::Constant::getNullValue(IntTy), name);
2824  Offset = CGF.Builder.CreateLoad(Offset);
2825  if (Offset->getType() != PtrDiffTy)
2826  Offset = CGF.Builder.CreateZExtOrBitCast(Offset, PtrDiffTy);
2827  return Offset;
2828  }
2829  uint64_t Offset = ComputeIvarBaseOffset(CGF.CGM, Interface, Ivar);
2830  return llvm::ConstantInt::get(PtrDiffTy, Offset, /*isSigned*/true);
2831 }
2832 
2833 CGObjCRuntime *
2835  switch (CGM.getLangOpts().ObjCRuntime.getKind()) {
2836  case ObjCRuntime::GNUstep:
2837  return new CGObjCGNUstep(CGM);
2838 
2839  case ObjCRuntime::GCC:
2840  return new CGObjCGCC(CGM);
2841 
2842  case ObjCRuntime::ObjFW:
2843  return new CGObjCObjFW(CGM);
2844 
2845  case ObjCRuntime::FragileMacOSX:
2846  case ObjCRuntime::MacOSX:
2847  case ObjCRuntime::iOS:
2848  llvm_unreachable("these runtimes are not GNU runtimes");
2849  }
2850  llvm_unreachable("bad runtime");
2851 }
Defines the clang::ASTContext interface.
static std::string SymbolNameForMethod(StringRef ClassName, StringRef CategoryName, const Selector MethodName, bool isClassMethod)
Definition: CGObjCGNU.cpp:876
ObjCInterfaceDecl * getDecl() const
getDecl - Get the declaration of this interface.
Definition: Type.h:4736
static Selector GetNullarySelector(StringRef name, ASTContext &Ctx)
Utility function for constructing a nullary selector.
Definition: ASTContext.h:2477
External linkage, which indicates that the entity can be referred to from other translation units...
Definition: Linkage.h:50
StringRef getName() const
Definition: Decl.h:168
protocol_range protocols() const
Definition: DeclObjC.h:1788
Smart pointer class that efficiently represents Objective-C method names.
Represents a version number in the form major[.minor[.subminor[.build]]].
Definition: VersionTuple.h:26
#define va_end(ap)
Definition: stdarg.h:34
Defines the clang::FileManager interface and associated types.
IdentifierInfo * getIdentifier() const
Definition: Decl.h:163
PropertyControl getPropertyImplementation() const
Definition: DeclObjC.h:2591
std::pair< llvm::Value *, llvm::Value * > getComplexVal() const
Definition: CGValue.h:61
llvm::AllocaInst * CreateTempAlloca(llvm::Type *Ty, const Twine &Name="tmp")
Definition: CGExpr.cpp:57
Implements runtime-specific code generation functions.
Definition: CGObjCRuntime.h:63
Defines the SourceManager interface.
QuantityType getQuantity() const
getQuantity - Get the raw integer representation of this quantity.
Definition: CharUnits.h:163
const Decl * CurCodeDecl
CurCodeDecl - This is the inner-most code context, which includes blocks.
Represents Objective-C's @throw statement.
Definition: StmtObjC.h:313
const ObjCObjectType * getObjectType() const
Definition: Type.h:4820
bool isWeakImported() const
Determine whether this is a weak-imported symbol.
Definition: DeclBase.cpp:515
const ASTRecordLayout & getASTObjCImplementationLayout(const ObjCImplementationDecl *D) const
Get or compute information about the layout of the specified Objective-C implementation.
Defines the Objective-C statement AST node classes.
bool isVoidType() const
Definition: Type.h:5426
llvm::Value * EmitObjCThrowOperand(const Expr *expr)
Definition: CGObjC.cpp:2782
This table allows us to fully hide how we implement multi-keyword caching.
llvm::Type * ConvertType(QualType T)
ConvertType - Convert type T into a llvm::Type.
Holds long-lived AST nodes (such as types and decls) that can be referred to throughout the semantic ...
Definition: ASTContext.h:89
bool isAnyPointerType() const
Definition: Type.h:5235
static const ObjCInterfaceDecl * FindIvarInterface(ASTContext &Context, const ObjCInterfaceDecl *OID, const ObjCIvarDecl *OIVD)
Definition: CGObjCGNU.cpp:2791
Keeps track of the various options that can be enabled, which controls the dialect of C or C++ that i...
Definition: LangOptions.h:48
Describes a module or submodule.
Definition: Basic/Module.h:49
RValue EmitCall(const CGFunctionInfo &FnInfo, llvm::Value *Callee, ReturnValueSlot ReturnValue, const CallArgList &Args, const Decl *TargetDecl=nullptr, llvm::Instruction **callOrInvoke=nullptr)
Definition: CGCall.cpp:3106
uint32_t Offset
Definition: CacheTokens.cpp:43
llvm::Value * getAggregateAddr() const
getAggregateAddr() - Return the Value* of the address of the aggregate.
Definition: CGValue.h:66
ObjCInterfaceDecl * getInterface() const
Definition: Type.h:4758
static OMPLinearClause * Create(const ASTContext &C, SourceLocation StartLoc, SourceLocation LParenLoc, SourceLocation ColonLoc, SourceLocation EndLoc, ArrayRef< Expr * > VL, ArrayRef< Expr * > IL, Expr *Step, Expr *CalcStep)
Creates clause with a list of variables VL and a linear step Step.
ObjCRuntime()
A bogus initialization of the runtime.
Definition: ObjCRuntime.h:61
std::string getNameAsString() const
Definition: Decl.h:183
ObjCProtocolDecl * getDefinition()
Retrieve the definition of this protocol, if any.
Definition: DeclObjC.h:1866
llvm::BasicBlock * createBasicBlock(const Twine &name="", llvm::Function *parent=nullptr, llvm::BasicBlock *before=nullptr)
createBasicBlock - Create an LLVM basic block.
Represents an Objective-C protocol declaration.
Definition: DeclObjC.h:1731
Represents an ObjC class declaration.
Definition: DeclObjC.h:851
propimpl_range property_impls() const
Definition: DeclObjC.h:2118
#define va_arg(ap, type)
Definition: stdarg.h:35
llvm::CallSite EmitRuntimeCallOrInvoke(llvm::Value *callee, ArrayRef< llvm::Value * > args, const Twine &name="")
Emits a call or invoke instruction to the given runtime function.
Definition: CGCall.cpp:3052
void addFrom(const CallArgList &other)
Definition: CGCall.h:85
const FileEntry * getFileEntryForID(FileID FID) const
Returns the FileEntry record for the provided FileID.
llvm::CallInst * EmitNounwindRuntimeCall(llvm::Value *callee, const Twine &name="")
CGBlockInfo - Information to generate a block literal.
Definition: CGBlocks.h:144
void getObjCEncodingForType(QualType T, std::string &S, const FieldDecl *Field=nullptr, QualType *NotEncodedT=nullptr) const
Emit the Objective-CC type encoding for the given type T into S.
ASTContext * Context
ID
Defines the set of possible language-specific address spaces.
Definition: AddressSpaces.h:27
SourceManager & SM
void InitTempAlloca(llvm::AllocaInst *Alloca, llvm::Value *Value)
InitTempAlloca - Provide an initial value for the given alloca.
Definition: CGExpr.cpp:64
StringRef getName() const
Return the actual identifier string.
bool isAggregate() const
Definition: CGValue.h:49
DeclContext * getDeclContext()
Definition: DeclBase.h:381
Represents Objective-C's @synchronized statement.
Definition: StmtObjC.h:262
void add(RValue rvalue, QualType type, bool needscopy=false)
Definition: CGCall.h:81
bool isObjCIdType() const
Definition: Type.h:5328
bool isInstanceMethod() const
Definition: DeclObjC.h:419
clang::ObjCRuntime ObjCRuntime
Definition: LangOptions.h:85
'gnustep' is the modern non-fragile GNUstep runtime.
Definition: ObjCRuntime.h:49
llvm::IRBuilder< PreserveNames, llvm::ConstantFolder, CGBuilderInserterTy > CGBuilderTy
Definition: CGBuilder.h:49
do v
Definition: arm_acle.h:77
ObjCCategoryDecl * getCategoryDecl() const
Definition: DeclObjC.cpp:1909
bool isIntegralOrEnumerationType() const
Determine whether this type is an integral or enumeration type.
Definition: Type.h:5476
const char * getName() const
Definition: FileManager.h:84
ASTContext & getContext() const
CharUnits getSize() const
getSize - Get the record size in characters.
Definition: RecordLayout.h:174
const ObjCInterfaceDecl * getClassInterface() const
Definition: DeclObjC.h:2409
SmallVector< llvm::Value *, 8 > ObjCEHValueStack
Cached information about one file (either on disk or in the virtual file system). ...
Definition: FileManager.h:53
const CGFunctionInfo & arrangeObjCMethodDeclaration(const ObjCMethodDecl *MD)
Definition: CGCall.cpp:282
const ObjCInterfaceDecl * getClassInterface() const
Definition: DeclObjC.h:2093
CanQual< Type > CanQualType
Represents a canonical, potentially-qualified type.
#define va_start(ap, param)
Definition: stdarg.h:33
const LangOptions & getLangOpts() const
std::string getAsString() const
Derive the full selector name (e.g. "foo:bar:") and return it as an std::string.
Represents one property declaration in an Objective-C interface.
Definition: DeclObjC.h:2424
const VersionTuple & getVersion() const
Definition: ObjCRuntime.h:72
FileID getMainFileID() const
Returns the FileID of the main source file.
const char * getName() const
Definition: FileManager.h:45
QualType getObjCSelType() const
Retrieve the type that corresponds to the predefined Objective-C 'SEL' type.
Definition: ASTContext.h:1520
ObjCIvarDecl * getNextIvar()
Definition: DeclObjC.h:1645
instmeth_range instance_methods() const
Definition: DeclObjC.h:742
bool isScalar() const
Definition: CGValue.h:47
prop_range properties() const
Definition: DeclObjC.h:714
return(x >> y)|(x<< (32-y))
std::string getNameAsString() const
Get the name of the class associated with this interface.
Definition: DeclObjC.h:2198
The basic abstraction for the target Objective-C runtime.
Definition: ObjCRuntime.h:25
llvm::Value * getScalarVal() const
getScalarVal() - Return the Value* of this scalar value.
Definition: CGValue.h:54
__builtin_va_list va_list
Definition: stdarg.h:30
const ObjCInterfaceType * getInterfaceType() const
Definition: Type.cpp:1423
std::unique_ptr< DiagnosticConsumer > create(StringRef OutputFile, DiagnosticOptions *Diags, bool MergeChildRecords=false)
Returns a DiagnosticConsumer that serializes diagnostics to a bitcode file.
StringRef getString() const
Definition: Expr.h:1521
Selector getSelector() const
Definition: DeclObjC.h:328
iterator begin() const
Definition: DeclObjC.h:65
ObjCMethodDecl * getGetterMethodDecl() const
Definition: DeclObjC.h:2581
const T * getAs() const
Definition: Type.h:5555
ObjCMethodDecl * getSetterMethodDecl() const
Definition: DeclObjC.h:2584
bool isObjCQualifiedIdType() const
Definition: Type.h:5318
Internal linkage, which indicates that the entity can be referred to from within the translation unit...
Definition: Linkage.h:33
protocol_range protocols() const
Definition: DeclObjC.h:1038
void EmitBlock(llvm::BasicBlock *BB, bool IsFinished=false)
Definition: CGStmt.cpp:348
bool getObjCEncodingForMethodDecl(const ObjCMethodDecl *Decl, std::string &S, bool Extended=false) const
Emit the encoded type for the method declaration Decl into S.
Kind getKind() const
Definition: ObjCRuntime.h:71
classmeth_range class_methods() const
Definition: DeclObjC.h:757
BoundNodesTreeBuilder *const Builder
StringRef getName() const
Definition: DeclObjC.h:2193
Represents Objective-C's @try ... @catch ... @finally statement.
Definition: StmtObjC.h:154
const Expr * getThrowExpr() const
Definition: StmtObjC.h:325
ObjCInterfaceDecl * getSuperClass() const
Definition: DeclObjC.cpp:271
llvm::Value * LoadObjCSelf()
Definition: CGObjC.cpp:1424
virtual bool isDynamic(OpenMPScheduleClauseKind ScheduleKind) const
Check if the specified ScheduleKind is dynamic. This kind of worksharing directive is emitted without...
ObjCIvarDecl * all_declared_ivar_begin()
Definition: DeclObjC.cpp:1433
const ASTRecordLayout & getASTObjCInterfaceLayout(const ObjCInterfaceDecl *D) const
Get or compute information about the layout of the specified Objective-C interface.
const DirectoryEntry * getDir() const
Return the directory the file lives in.
Definition: FileManager.h:93
This class handles loading and caching of source files into memory.
iterator end() const
Definition: DeclObjC.h:66
const ObjCProtocolList & getReferencedProtocols() const
Definition: DeclObjC.h:2006
CGObjCRuntime * CreateGNUObjCRuntime(CodeGenModule &CGM)
Creates an instance of an Objective-C runtime class.
Definition: CGObjCGNU.cpp:2834
llvm::FunctionType * GetFunctionType(const CGFunctionInfo &Info)
GetFunctionType - Get the LLVM function type for.
Definition: CGCall.cpp:1253