1 //===------- CGObjCGNU.cpp - Emit LLVM Code from ASTs for a Module --------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This 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.
15 //===----------------------------------------------------------------------===//
17 #include "CGObjCRuntime.h"
18 #include "CodeGenModule.h"
19 #include "CodeGenFunction.h"
20 #include "CGCleanup.h"
22 #include "clang/AST/ASTContext.h"
23 #include "clang/AST/Decl.h"
24 #include "clang/AST/DeclObjC.h"
25 #include "clang/AST/RecordLayout.h"
26 #include "clang/AST/StmtObjC.h"
27 #include "clang/Basic/SourceManager.h"
28 #include "clang/Basic/FileManager.h"
30 #include "llvm/Intrinsics.h"
31 #include "llvm/Module.h"
32 #include "llvm/LLVMContext.h"
33 #include "llvm/ADT/SmallVector.h"
34 #include "llvm/ADT/StringMap.h"
35 #include "llvm/Support/CallSite.h"
36 #include "llvm/Support/Compiler.h"
37 #include "llvm/Target/TargetData.h"
42 using namespace clang;
43 using namespace CodeGen;
47 /// Class that lazily initialises the runtime function. Avoids inserting the
48 /// types and the function declaration into a module if they're not used, and
49 /// avoids constructing the type more than once if it's used more than once.
50 class LazyRuntimeFunction {
52 std::vector<llvm::Type*> ArgTys;
53 const char *FunctionName;
54 llvm::Constant *Function;
56 /// Constructor leaves this class uninitialized, because it is intended to
57 /// be used as a field in another class and not all of the types that are
58 /// used as arguments will necessarily be available at construction time.
59 LazyRuntimeFunction() : CGM(0), FunctionName(0), Function(0) {}
61 /// Initialises the lazy function with the name, return type, and the types
64 void init(CodeGenModule *Mod, const char *name,
65 llvm::Type *RetTy, ...) {
71 va_start(Args, RetTy);
72 while (llvm::Type *ArgTy = va_arg(Args, llvm::Type*))
73 ArgTys.push_back(ArgTy);
75 // Push the return type on at the end so we can pop it off easily
76 ArgTys.push_back(RetTy);
78 /// Overloaded cast operator, allows the class to be implicitly cast to an
80 operator llvm::Constant*() {
82 if (0 == FunctionName) return 0;
83 // We put the return type on the end of the vector, so pop it back off
84 llvm::Type *RetTy = ArgTys.back();
86 llvm::FunctionType *FTy = llvm::FunctionType::get(RetTy, ArgTys, false);
88 cast<llvm::Constant>(CGM->CreateRuntimeFunction(FTy, FunctionName));
89 // We won't need to use the types again, so we may as well clean up the
95 operator llvm::Function*() {
96 return cast<llvm::Function>((llvm::Constant*)*this);
102 /// GNU Objective-C runtime code generation. This class implements the parts of
103 /// Objective-C support that are specific to the GNU family of runtimes (GCC and
105 class CGObjCGNU : public CGObjCRuntime {
107 /// The module that is using this class
109 /// The LLVM module into which output is inserted
110 llvm::Module &TheModule;
111 /// strut objc_super. Used for sending messages to super. This structure
112 /// contains the receiver (object) and the expected class.
113 llvm::StructType *ObjCSuperTy;
114 /// struct objc_super*. The type of the argument to the superclass message
115 /// lookup functions.
116 llvm::PointerType *PtrToObjCSuperTy;
117 /// LLVM type for selectors. Opaque pointer (i8*) unless a header declaring
118 /// SEL is included in a header somewhere, in which case it will be whatever
119 /// type is declared in that header, most likely {i8*, i8*}.
120 llvm::PointerType *SelectorTy;
121 /// LLVM i8 type. Cached here to avoid repeatedly getting it in all of the
122 /// places where it's used
123 llvm::IntegerType *Int8Ty;
124 /// Pointer to i8 - LLVM type of char*, for all of the places where the
125 /// runtime needs to deal with C strings.
126 llvm::PointerType *PtrToInt8Ty;
127 /// Instance Method Pointer type. This is a pointer to a function that takes,
128 /// at a minimum, an object and a selector, and is the generic type for
129 /// Objective-C methods. Due to differences between variadic / non-variadic
130 /// calling conventions, it must always be cast to the correct type before
131 /// actually being used.
132 llvm::PointerType *IMPTy;
133 /// Type of an untyped Objective-C object. Clang treats id as a built-in type
134 /// when compiling Objective-C code, so this may be an opaque pointer (i8*),
135 /// but if the runtime header declaring it is included then it may be a
136 /// pointer to a structure.
137 llvm::PointerType *IdTy;
138 /// Pointer to a pointer to an Objective-C object. Used in the new ABI
139 /// message lookup function and some GC-related functions.
140 llvm::PointerType *PtrToIdTy;
141 /// The clang type of id. Used when using the clang CGCall infrastructure to
142 /// call Objective-C methods.
144 /// LLVM type for C int type.
145 llvm::IntegerType *IntTy;
146 /// LLVM type for an opaque pointer. This is identical to PtrToInt8Ty, but is
147 /// used in the code to document the difference between i8* meaning a pointer
148 /// to a C string and i8* meaning a pointer to some opaque type.
149 llvm::PointerType *PtrTy;
150 /// LLVM type for C long type. The runtime uses this in a lot of places where
151 /// it should be using intptr_t, but we can't fix this without breaking
152 /// compatibility with GCC...
153 llvm::IntegerType *LongTy;
154 /// LLVM type for C size_t. Used in various runtime data structures.
155 llvm::IntegerType *SizeTy;
156 /// LLVM type for C intptr_t.
157 llvm::IntegerType *IntPtrTy;
158 /// LLVM type for C ptrdiff_t. Mainly used in property accessor functions.
159 llvm::IntegerType *PtrDiffTy;
160 /// LLVM type for C int*. Used for GCC-ABI-compatible non-fragile instance
162 llvm::PointerType *PtrToIntTy;
163 /// LLVM type for Objective-C BOOL type.
165 /// 32-bit integer type, to save us needing to look it up every time it's used.
166 llvm::IntegerType *Int32Ty;
167 /// 64-bit integer type, to save us needing to look it up every time it's used.
168 llvm::IntegerType *Int64Ty;
169 /// Metadata kind used to tie method lookups to message sends. The GNUstep
170 /// runtime provides some LLVM passes that can use this to do things like
171 /// automatic IMP caching and speculative inlining.
172 unsigned msgSendMDKind;
173 /// Helper function that generates a constant string and returns a pointer to
174 /// the start of the string. The result of this function can be used anywhere
175 /// where the C code specifies const char*.
176 llvm::Constant *MakeConstantString(const std::string &Str,
177 const std::string &Name="") {
178 llvm::Constant *ConstStr = CGM.GetAddrOfConstantCString(Str, Name.c_str());
179 return llvm::ConstantExpr::getGetElementPtr(ConstStr, Zeros);
181 /// Emits a linkonce_odr string, whose name is the prefix followed by the
182 /// string value. This allows the linker to combine the strings between
183 /// different modules. Used for EH typeinfo names, selector strings, and a
184 /// few other things.
185 llvm::Constant *ExportUniqueString(const std::string &Str,
186 const std::string prefix) {
187 std::string name = prefix + Str;
188 llvm::Constant *ConstStr = TheModule.getGlobalVariable(name);
190 llvm::Constant *value = llvm::ConstantArray::get(VMContext, Str, true);
191 ConstStr = new llvm::GlobalVariable(TheModule, value->getType(), true,
192 llvm::GlobalValue::LinkOnceODRLinkage, value, prefix + Str);
194 return llvm::ConstantExpr::getGetElementPtr(ConstStr, Zeros);
196 /// Generates a global structure, initialized by the elements in the vector.
197 /// The element types must match the types of the structure elements in the
199 llvm::GlobalVariable *MakeGlobal(llvm::StructType *Ty,
200 llvm::ArrayRef<llvm::Constant*> V,
202 llvm::GlobalValue::LinkageTypes linkage
203 =llvm::GlobalValue::InternalLinkage) {
204 llvm::Constant *C = llvm::ConstantStruct::get(Ty, V);
205 return new llvm::GlobalVariable(TheModule, Ty, false,
208 /// Generates a global array. The vector must contain the same number of
209 /// elements that the array type declares, of the type specified as the array
211 llvm::GlobalVariable *MakeGlobal(llvm::ArrayType *Ty,
212 llvm::ArrayRef<llvm::Constant*> V,
214 llvm::GlobalValue::LinkageTypes linkage
215 =llvm::GlobalValue::InternalLinkage) {
216 llvm::Constant *C = llvm::ConstantArray::get(Ty, V);
217 return new llvm::GlobalVariable(TheModule, Ty, false,
220 /// Generates a global array, inferring the array type from the specified
221 /// element type and the size of the initialiser.
222 llvm::GlobalVariable *MakeGlobalArray(llvm::Type *Ty,
223 llvm::ArrayRef<llvm::Constant*> V,
225 llvm::GlobalValue::LinkageTypes linkage
226 =llvm::GlobalValue::InternalLinkage) {
227 llvm::ArrayType *ArrayTy = llvm::ArrayType::get(Ty, V.size());
228 return MakeGlobal(ArrayTy, V, Name, linkage);
230 /// Ensures that the value has the required type, by inserting a bitcast if
231 /// required. This function lets us avoid inserting bitcasts that are
233 llvm::Value* EnforceType(CGBuilderTy B, llvm::Value *V, llvm::Type *Ty){
234 if (V->getType() == Ty) return V;
235 return B.CreateBitCast(V, Ty);
237 // Some zeros used for GEPs in lots of places.
238 llvm::Constant *Zeros[2];
239 /// Null pointer value. Mainly used as a terminator in various arrays.
240 llvm::Constant *NULLPtr;
242 llvm::LLVMContext &VMContext;
244 /// Placeholder for the class. Lots of things refer to the class before we've
245 /// actually emitted it. We use this alias as a placeholder, and then replace
246 /// it with a pointer to the class structure before finally emitting the
248 llvm::GlobalAlias *ClassPtrAlias;
249 /// Placeholder for the metaclass. Lots of things refer to the class before
250 /// we've / actually emitted it. We use this alias as a placeholder, and then
251 /// replace / it with a pointer to the metaclass structure before finally
252 /// emitting the / module.
253 llvm::GlobalAlias *MetaClassPtrAlias;
254 /// All of the classes that have been generated for this compilation units.
255 std::vector<llvm::Constant*> Classes;
256 /// All of the categories that have been generated for this compilation units.
257 std::vector<llvm::Constant*> Categories;
258 /// All of the Objective-C constant strings that have been generated for this
259 /// compilation units.
260 std::vector<llvm::Constant*> ConstantStrings;
261 /// Map from string values to Objective-C constant strings in the output.
262 /// Used to prevent emitting Objective-C strings more than once. This should
263 /// not be required at all - CodeGenModule should manage this list.
264 llvm::StringMap<llvm::Constant*> ObjCStrings;
265 /// All of the protocols that have been declared.
266 llvm::StringMap<llvm::Constant*> ExistingProtocols;
267 /// For each variant of a selector, we store the type encoding and a
268 /// placeholder value. For an untyped selector, the type will be the empty
269 /// string. Selector references are all done via the module's selector table,
270 /// so we create an alias as a placeholder and then replace it with the real
272 typedef std::pair<std::string, llvm::GlobalAlias*> TypedSelector;
273 /// Type of the selector map. This is roughly equivalent to the structure
274 /// used in the GNUstep runtime, which maintains a list of all of the valid
275 /// types for a selector in a table.
276 typedef llvm::DenseMap<Selector, SmallVector<TypedSelector, 2> >
278 /// A map from selectors to selector types. This allows us to emit all
279 /// selectors of the same name and type together.
280 SelectorMap SelectorTable;
282 /// Selectors related to memory management. When compiling in GC mode, we
284 Selector RetainSel, ReleaseSel, AutoreleaseSel;
285 /// Runtime functions used for memory management in GC mode. Note that clang
286 /// supports code generation for calling these functions, but neither GNU
287 /// runtime actually supports this API properly yet.
288 LazyRuntimeFunction IvarAssignFn, StrongCastAssignFn, MemMoveFn, WeakReadFn,
289 WeakAssignFn, GlobalAssignFn;
292 /// Function used for throwing Objective-C exceptions.
293 LazyRuntimeFunction ExceptionThrowFn;
294 /// Function used for rethrowing exceptions, used at the end of @finally or
295 /// @synchronize blocks.
296 LazyRuntimeFunction ExceptionReThrowFn;
297 /// Function called when entering a catch function. This is required for
298 /// differentiating Objective-C exceptions and foreign exceptions.
299 LazyRuntimeFunction EnterCatchFn;
300 /// Function called when exiting from a catch block. Used to do exception
302 LazyRuntimeFunction ExitCatchFn;
303 /// Function called when entering an @synchronize block. Acquires the lock.
304 LazyRuntimeFunction SyncEnterFn;
305 /// Function called when exiting an @synchronize block. Releases the lock.
306 LazyRuntimeFunction SyncExitFn;
310 /// Function called if fast enumeration detects that the collection is
311 /// modified during the update.
312 LazyRuntimeFunction EnumerationMutationFn;
313 /// Function for implementing synthesized property getters that return an
315 LazyRuntimeFunction GetPropertyFn;
316 /// Function for implementing synthesized property setters that return an
318 LazyRuntimeFunction SetPropertyFn;
319 /// Function used for non-object declared property getters.
320 LazyRuntimeFunction GetStructPropertyFn;
321 /// Function used for non-object declared property setters.
322 LazyRuntimeFunction SetStructPropertyFn;
324 /// The version of the runtime that this class targets. Must match the
325 /// version in the runtime.
327 /// The version of the protocol class. Used to differentiate between ObjC1
328 /// and ObjC2 protocols. Objective-C 1 protocols can not contain optional
329 /// components and can not contain declared properties. We always emit
330 /// Objective-C 2 property structures, but we have to pretend that they're
331 /// Objective-C 1 property structures when targeting the GCC runtime or it
333 const int ProtocolVersion;
335 /// Generates an instance variable list structure. This is a structure
336 /// containing a size and an array of structures containing instance variable
337 /// metadata. This is used purely for introspection in the fragile ABI. In
338 /// the non-fragile ABI, it's used for instance variable fixup.
339 llvm::Constant *GenerateIvarList(
340 const SmallVectorImpl<llvm::Constant *> &IvarNames,
341 const SmallVectorImpl<llvm::Constant *> &IvarTypes,
342 const SmallVectorImpl<llvm::Constant *> &IvarOffsets);
343 /// Generates a method list structure. This is a structure containing a size
344 /// and an array of structures containing method metadata.
346 /// This structure is used by both classes and categories, and contains a next
347 /// pointer allowing them to be chained together in a linked list.
348 llvm::Constant *GenerateMethodList(const StringRef &ClassName,
349 const StringRef &CategoryName,
350 const SmallVectorImpl<Selector> &MethodSels,
351 const SmallVectorImpl<llvm::Constant *> &MethodTypes,
352 bool isClassMethodList);
353 /// Emits an empty protocol. This is used for @protocol() where no protocol
354 /// is found. The runtime will (hopefully) fix up the pointer to refer to the
356 llvm::Constant *GenerateEmptyProtocol(const std::string &ProtocolName);
357 /// Generates a list of property metadata structures. This follows the same
358 /// pattern as method and instance variable metadata lists.
359 llvm::Constant *GeneratePropertyList(const ObjCImplementationDecl *OID,
360 SmallVectorImpl<Selector> &InstanceMethodSels,
361 SmallVectorImpl<llvm::Constant*> &InstanceMethodTypes);
362 /// Generates a list of referenced protocols. Classes, categories, and
363 /// protocols all use this structure.
364 llvm::Constant *GenerateProtocolList(
365 const SmallVectorImpl<std::string> &Protocols);
366 /// To ensure that all protocols are seen by the runtime, we add a category on
367 /// a class defined in the runtime, declaring no methods, but adopting the
368 /// protocols. This is a horribly ugly hack, but it allows us to collect all
369 /// of the protocols without changing the ABI.
370 void GenerateProtocolHolderCategory(void);
371 /// Generates a class structure.
372 llvm::Constant *GenerateClassStructure(
373 llvm::Constant *MetaClass,
374 llvm::Constant *SuperClass,
377 llvm::Constant *Version,
378 llvm::Constant *InstanceSize,
379 llvm::Constant *IVars,
380 llvm::Constant *Methods,
381 llvm::Constant *Protocols,
382 llvm::Constant *IvarOffsets,
383 llvm::Constant *Properties,
384 llvm::Constant *StrongIvarBitmap,
385 llvm::Constant *WeakIvarBitmap,
387 /// Generates a method list. This is used by protocols to define the required
388 /// and optional methods.
389 llvm::Constant *GenerateProtocolMethodList(
390 const SmallVectorImpl<llvm::Constant *> &MethodNames,
391 const SmallVectorImpl<llvm::Constant *> &MethodTypes);
392 /// Returns a selector with the specified type encoding. An empty string is
393 /// used to return an untyped selector (with the types field set to NULL).
394 llvm::Value *GetSelector(CGBuilderTy &Builder, Selector Sel,
395 const std::string &TypeEncoding, bool lval);
396 /// Returns the variable used to store the offset of an instance variable.
397 llvm::GlobalVariable *ObjCIvarOffsetVariable(const ObjCInterfaceDecl *ID,
398 const ObjCIvarDecl *Ivar);
399 /// Emits a reference to a class. This allows the linker to object if there
400 /// is no class of the matching name.
401 void EmitClassRef(const std::string &className);
402 /// Emits a pointer to the named class
403 llvm::Value *GetClassNamed(CGBuilderTy &Builder, const std::string &Name,
406 /// Looks up the method for sending a message to the specified object. This
407 /// mechanism differs between the GCC and GNU runtimes, so this method must be
408 /// overridden in subclasses.
409 virtual llvm::Value *LookupIMP(CodeGenFunction &CGF,
410 llvm::Value *&Receiver,
412 llvm::MDNode *node) = 0;
413 /// Looks up the method for sending a message to a superclass. This
414 /// mechanism differs between the GCC and GNU runtimes, so this method must
415 /// be overridden in subclasses.
416 virtual llvm::Value *LookupIMPSuper(CodeGenFunction &CGF,
417 llvm::Value *ObjCSuper,
418 llvm::Value *cmd) = 0;
419 /// Libobjc2 uses a bitfield representation where small(ish) bitfields are
420 /// stored in a 64-bit value with the low bit set to 1 and the remaining 63
421 /// bits set to their values, LSB first, while larger ones are stored in a
422 /// structure of this / form:
424 /// struct { int32_t length; int32_t values[length]; };
426 /// The values in the array are stored in host-endian format, with the least
427 /// significant bit being assumed to come first in the bitfield. Therefore,
428 /// a bitfield with the 64th bit set will be (int64_t)&{ 2, [0, 1<<31] },
429 /// while a bitfield / with the 63rd bit set will be 1<<64.
430 llvm::Constant *MakeBitField(llvm::SmallVectorImpl<bool> &bits);
432 CGObjCGNU(CodeGenModule &cgm, unsigned runtimeABIVersion,
433 unsigned protocolClassVersion);
435 virtual llvm::Constant *GenerateConstantString(const StringLiteral *);
438 GenerateMessageSend(CodeGenFunction &CGF,
439 ReturnValueSlot Return,
442 llvm::Value *Receiver,
443 const CallArgList &CallArgs,
444 const ObjCInterfaceDecl *Class,
445 const ObjCMethodDecl *Method);
447 GenerateMessageSendSuper(CodeGenFunction &CGF,
448 ReturnValueSlot Return,
451 const ObjCInterfaceDecl *Class,
453 llvm::Value *Receiver,
455 const CallArgList &CallArgs,
456 const ObjCMethodDecl *Method);
457 virtual llvm::Value *GetClass(CGBuilderTy &Builder,
458 const ObjCInterfaceDecl *OID);
459 virtual llvm::Value *GetSelector(CGBuilderTy &Builder, Selector Sel,
461 virtual llvm::Value *GetSelector(CGBuilderTy &Builder, const ObjCMethodDecl
463 virtual llvm::Constant *GetEHType(QualType T);
465 virtual llvm::Function *GenerateMethod(const ObjCMethodDecl *OMD,
466 const ObjCContainerDecl *CD);
467 virtual void GenerateCategory(const ObjCCategoryImplDecl *CMD);
468 virtual void GenerateClass(const ObjCImplementationDecl *ClassDecl);
469 virtual llvm::Value *GenerateProtocolRef(CGBuilderTy &Builder,
470 const ObjCProtocolDecl *PD);
471 virtual void GenerateProtocol(const ObjCProtocolDecl *PD);
472 virtual llvm::Function *ModuleInitFunction();
473 virtual llvm::Constant *GetPropertyGetFunction();
474 virtual llvm::Constant *GetPropertySetFunction();
475 virtual llvm::Constant *GetSetStructFunction();
476 virtual llvm::Constant *GetGetStructFunction();
477 virtual llvm::Constant *EnumerationMutationFunction();
479 virtual void EmitTryStmt(CodeGenFunction &CGF,
480 const ObjCAtTryStmt &S);
481 virtual void EmitSynchronizedStmt(CodeGenFunction &CGF,
482 const ObjCAtSynchronizedStmt &S);
483 virtual void EmitThrowStmt(CodeGenFunction &CGF,
484 const ObjCAtThrowStmt &S);
485 virtual llvm::Value * EmitObjCWeakRead(CodeGenFunction &CGF,
486 llvm::Value *AddrWeakObj);
487 virtual void EmitObjCWeakAssign(CodeGenFunction &CGF,
488 llvm::Value *src, llvm::Value *dst);
489 virtual void EmitObjCGlobalAssign(CodeGenFunction &CGF,
490 llvm::Value *src, llvm::Value *dest,
491 bool threadlocal=false);
492 virtual void EmitObjCIvarAssign(CodeGenFunction &CGF,
493 llvm::Value *src, llvm::Value *dest,
494 llvm::Value *ivarOffset);
495 virtual void EmitObjCStrongCastAssign(CodeGenFunction &CGF,
496 llvm::Value *src, llvm::Value *dest);
497 virtual void EmitGCMemmoveCollectable(CodeGenFunction &CGF,
498 llvm::Value *DestPtr,
501 virtual LValue EmitObjCValueForIvar(CodeGenFunction &CGF,
503 llvm::Value *BaseValue,
504 const ObjCIvarDecl *Ivar,
505 unsigned CVRQualifiers);
506 virtual llvm::Value *EmitIvarOffset(CodeGenFunction &CGF,
507 const ObjCInterfaceDecl *Interface,
508 const ObjCIvarDecl *Ivar);
509 virtual llvm::Value *EmitNSAutoreleasePoolClassRef(CGBuilderTy &Builder);
510 virtual llvm::Constant *BuildGCBlockLayout(CodeGenModule &CGM,
511 const CGBlockInfo &blockInfo) {
515 virtual llvm::GlobalVariable *GetClassGlobal(const std::string &Name) {
519 /// Class representing the legacy GCC Objective-C ABI. This is the default when
520 /// -fobjc-nonfragile-abi is not specified.
522 /// The GCC ABI target actually generates code that is approximately compatible
523 /// with the new GNUstep runtime ABI, but refrains from using any features that
524 /// would not work with the GCC runtime. For example, clang always generates
525 /// the extended form of the class structure, and the extra fields are simply
526 /// ignored by GCC libobjc.
527 class CGObjCGCC : public CGObjCGNU {
528 /// The GCC ABI message lookup function. Returns an IMP pointing to the
529 /// method implementation for this message.
530 LazyRuntimeFunction MsgLookupFn;
531 /// The GCC ABI superclass message lookup function. Takes a pointer to a
532 /// structure describing the receiver and the class, and a selector as
533 /// arguments. Returns the IMP for the corresponding method.
534 LazyRuntimeFunction MsgLookupSuperFn;
536 virtual llvm::Value *LookupIMP(CodeGenFunction &CGF,
537 llvm::Value *&Receiver,
539 llvm::MDNode *node) {
540 CGBuilderTy &Builder = CGF.Builder;
541 llvm::Value *imp = Builder.CreateCall2(MsgLookupFn,
542 EnforceType(Builder, Receiver, IdTy),
543 EnforceType(Builder, cmd, SelectorTy));
544 cast<llvm::CallInst>(imp)->setMetadata(msgSendMDKind, node);
547 virtual llvm::Value *LookupIMPSuper(CodeGenFunction &CGF,
548 llvm::Value *ObjCSuper,
550 CGBuilderTy &Builder = CGF.Builder;
551 llvm::Value *lookupArgs[] = {EnforceType(Builder, ObjCSuper,
552 PtrToObjCSuperTy), cmd};
553 return Builder.CreateCall(MsgLookupSuperFn, lookupArgs);
556 CGObjCGCC(CodeGenModule &Mod) : CGObjCGNU(Mod, 8, 2) {
557 // IMP objc_msg_lookup(id, SEL);
558 MsgLookupFn.init(&CGM, "objc_msg_lookup", IMPTy, IdTy, SelectorTy, NULL);
559 // IMP objc_msg_lookup_super(struct objc_super*, SEL);
560 MsgLookupSuperFn.init(&CGM, "objc_msg_lookup_super", IMPTy,
561 PtrToObjCSuperTy, SelectorTy, NULL);
564 /// Class used when targeting the new GNUstep runtime ABI.
565 class CGObjCGNUstep : public CGObjCGNU {
566 /// The slot lookup function. Returns a pointer to a cacheable structure
567 /// that contains (among other things) the IMP.
568 LazyRuntimeFunction SlotLookupFn;
569 /// The GNUstep ABI superclass message lookup function. Takes a pointer to
570 /// a structure describing the receiver and the class, and a selector as
571 /// arguments. Returns the slot for the corresponding method. Superclass
572 /// message lookup rarely changes, so this is a good caching opportunity.
573 LazyRuntimeFunction SlotLookupSuperFn;
574 /// Type of an slot structure pointer. This is returned by the various
575 /// lookup functions.
578 virtual llvm::Value *LookupIMP(CodeGenFunction &CGF,
579 llvm::Value *&Receiver,
581 llvm::MDNode *node) {
582 CGBuilderTy &Builder = CGF.Builder;
583 llvm::Function *LookupFn = SlotLookupFn;
585 // Store the receiver on the stack so that we can reload it later
586 llvm::Value *ReceiverPtr = CGF.CreateTempAlloca(Receiver->getType());
587 Builder.CreateStore(Receiver, ReceiverPtr);
591 if (isa<ObjCMethodDecl>(CGF.CurCodeDecl)) {
592 self = CGF.LoadObjCSelf();
594 self = llvm::ConstantPointerNull::get(IdTy);
597 // The lookup function is guaranteed not to capture the receiver pointer.
598 LookupFn->setDoesNotCapture(1);
600 llvm::CallInst *slot =
601 Builder.CreateCall3(LookupFn,
602 EnforceType(Builder, ReceiverPtr, PtrToIdTy),
603 EnforceType(Builder, cmd, SelectorTy),
604 EnforceType(Builder, self, IdTy));
605 slot->setOnlyReadsMemory();
606 slot->setMetadata(msgSendMDKind, node);
608 // Load the imp from the slot
609 llvm::Value *imp = Builder.CreateLoad(Builder.CreateStructGEP(slot, 4));
611 // The lookup function may have changed the receiver, so make sure we use
613 Receiver = Builder.CreateLoad(ReceiverPtr, true);
616 virtual llvm::Value *LookupIMPSuper(CodeGenFunction &CGF,
617 llvm::Value *ObjCSuper,
619 CGBuilderTy &Builder = CGF.Builder;
620 llvm::Value *lookupArgs[] = {ObjCSuper, cmd};
622 llvm::CallInst *slot = Builder.CreateCall(SlotLookupSuperFn, lookupArgs);
623 slot->setOnlyReadsMemory();
625 return Builder.CreateLoad(Builder.CreateStructGEP(slot, 4));
628 CGObjCGNUstep(CodeGenModule &Mod) : CGObjCGNU(Mod, 9, 3) {
629 llvm::StructType *SlotStructTy = llvm::StructType::get(PtrTy,
630 PtrTy, PtrTy, IntTy, IMPTy, NULL);
631 SlotTy = llvm::PointerType::getUnqual(SlotStructTy);
632 // Slot_t objc_msg_lookup_sender(id *receiver, SEL selector, id sender);
633 SlotLookupFn.init(&CGM, "objc_msg_lookup_sender", SlotTy, PtrToIdTy,
634 SelectorTy, IdTy, NULL);
635 // Slot_t objc_msg_lookup_super(struct objc_super*, SEL);
636 SlotLookupSuperFn.init(&CGM, "objc_slot_lookup_super", SlotTy,
637 PtrToObjCSuperTy, SelectorTy, NULL);
638 // If we're in ObjC++ mode, then we want to make
639 if (CGM.getLangOptions().CPlusPlus) {
640 llvm::Type *VoidTy = llvm::Type::getVoidTy(VMContext);
641 // void *__cxa_begin_catch(void *e)
642 EnterCatchFn.init(&CGM, "__cxa_begin_catch", PtrTy, PtrTy, NULL);
643 // void __cxa_end_catch(void)
644 ExitCatchFn.init(&CGM, "__cxa_end_catch", VoidTy, NULL);
645 // void _Unwind_Resume_or_Rethrow(void*)
646 ExceptionReThrowFn.init(&CGM, "_Unwind_Resume_or_Rethrow", VoidTy, PtrTy, NULL);
651 } // end anonymous namespace
654 /// Emits a reference to a dummy variable which is emitted with each class.
655 /// This ensures that a linker error will be generated when trying to link
656 /// together modules where a referenced class is not defined.
657 void CGObjCGNU::EmitClassRef(const std::string &className) {
658 std::string symbolRef = "__objc_class_ref_" + className;
659 // Don't emit two copies of the same symbol
660 if (TheModule.getGlobalVariable(symbolRef))
662 std::string symbolName = "__objc_class_name_" + className;
663 llvm::GlobalVariable *ClassSymbol = TheModule.getGlobalVariable(symbolName);
665 ClassSymbol = new llvm::GlobalVariable(TheModule, LongTy, false,
666 llvm::GlobalValue::ExternalLinkage, 0, symbolName);
668 new llvm::GlobalVariable(TheModule, ClassSymbol->getType(), true,
669 llvm::GlobalValue::WeakAnyLinkage, ClassSymbol, symbolRef);
672 static std::string SymbolNameForMethod(const StringRef &ClassName,
673 const StringRef &CategoryName, const Selector MethodName,
674 bool isClassMethod) {
675 std::string MethodNameColonStripped = MethodName.getAsString();
676 std::replace(MethodNameColonStripped.begin(), MethodNameColonStripped.end(),
678 return (Twine(isClassMethod ? "_c_" : "_i_") + ClassName + "_" +
679 CategoryName + "_" + MethodNameColonStripped).str();
682 CGObjCGNU::CGObjCGNU(CodeGenModule &cgm, unsigned runtimeABIVersion,
683 unsigned protocolClassVersion)
684 : CGM(cgm), TheModule(CGM.getModule()), VMContext(cgm.getLLVMContext()),
685 ClassPtrAlias(0), MetaClassPtrAlias(0), RuntimeVersion(runtimeABIVersion),
686 ProtocolVersion(protocolClassVersion) {
688 msgSendMDKind = VMContext.getMDKindID("GNUObjCMessageSend");
690 CodeGenTypes &Types = CGM.getTypes();
691 IntTy = cast<llvm::IntegerType>(
692 Types.ConvertType(CGM.getContext().IntTy));
693 LongTy = cast<llvm::IntegerType>(
694 Types.ConvertType(CGM.getContext().LongTy));
695 SizeTy = cast<llvm::IntegerType>(
696 Types.ConvertType(CGM.getContext().getSizeType()));
697 PtrDiffTy = cast<llvm::IntegerType>(
698 Types.ConvertType(CGM.getContext().getPointerDiffType()));
699 BoolTy = CGM.getTypes().ConvertType(CGM.getContext().BoolTy);
701 Int8Ty = llvm::Type::getInt8Ty(VMContext);
702 // C string type. Used in lots of places.
703 PtrToInt8Ty = llvm::PointerType::getUnqual(Int8Ty);
705 Zeros[0] = llvm::ConstantInt::get(LongTy, 0);
707 NULLPtr = llvm::ConstantPointerNull::get(PtrToInt8Ty);
708 // Get the selector Type.
709 QualType selTy = CGM.getContext().getObjCSelType();
710 if (QualType() == selTy) {
711 SelectorTy = PtrToInt8Ty;
713 SelectorTy = cast<llvm::PointerType>(CGM.getTypes().ConvertType(selTy));
716 PtrToIntTy = llvm::PointerType::getUnqual(IntTy);
719 Int32Ty = llvm::Type::getInt32Ty(VMContext);
720 Int64Ty = llvm::Type::getInt64Ty(VMContext);
723 TheModule.getPointerSize() == llvm::Module::Pointer32 ? Int32Ty : Int64Ty;
726 QualType UnqualIdTy = CGM.getContext().getObjCIdType();
727 ASTIdTy = CanQualType();
728 if (UnqualIdTy != QualType()) {
729 ASTIdTy = CGM.getContext().getCanonicalType(UnqualIdTy);
730 IdTy = cast<llvm::PointerType>(CGM.getTypes().ConvertType(ASTIdTy));
734 PtrToIdTy = llvm::PointerType::getUnqual(IdTy);
736 ObjCSuperTy = llvm::StructType::get(IdTy, IdTy, NULL);
737 PtrToObjCSuperTy = llvm::PointerType::getUnqual(ObjCSuperTy);
739 llvm::Type *VoidTy = llvm::Type::getVoidTy(VMContext);
741 // void objc_exception_throw(id);
742 ExceptionThrowFn.init(&CGM, "objc_exception_throw", VoidTy, IdTy, NULL);
743 ExceptionReThrowFn.init(&CGM, "objc_exception_throw", VoidTy, IdTy, NULL);
744 // int objc_sync_enter(id);
745 SyncEnterFn.init(&CGM, "objc_sync_enter", IntTy, IdTy, NULL);
746 // int objc_sync_exit(id);
747 SyncExitFn.init(&CGM, "objc_sync_exit", IntTy, IdTy, NULL);
749 // void objc_enumerationMutation (id)
750 EnumerationMutationFn.init(&CGM, "objc_enumerationMutation", VoidTy,
753 // id objc_getProperty(id, SEL, ptrdiff_t, BOOL)
754 GetPropertyFn.init(&CGM, "objc_getProperty", IdTy, IdTy, SelectorTy,
755 PtrDiffTy, BoolTy, NULL);
756 // void objc_setProperty(id, SEL, ptrdiff_t, id, BOOL, BOOL)
757 SetPropertyFn.init(&CGM, "objc_setProperty", VoidTy, IdTy, SelectorTy,
758 PtrDiffTy, IdTy, BoolTy, BoolTy, NULL);
759 // void objc_setPropertyStruct(void*, void*, ptrdiff_t, BOOL, BOOL)
760 GetStructPropertyFn.init(&CGM, "objc_getPropertyStruct", VoidTy, PtrTy, PtrTy,
761 PtrDiffTy, BoolTy, BoolTy, NULL);
762 // void objc_setPropertyStruct(void*, void*, ptrdiff_t, BOOL, BOOL)
763 SetStructPropertyFn.init(&CGM, "objc_setPropertyStruct", VoidTy, PtrTy, PtrTy,
764 PtrDiffTy, BoolTy, BoolTy, NULL);
767 llvm::Type *IMPArgs[] = { IdTy, SelectorTy };
768 IMPTy = llvm::PointerType::getUnqual(llvm::FunctionType::get(IdTy, IMPArgs,
771 const LangOptions &Opts = CGM.getLangOptions();
772 if ((Opts.getGC() != LangOptions::NonGC) || Opts.ObjCAutoRefCount)
775 // Don't bother initialising the GC stuff unless we're compiling in GC mode
776 if (Opts.getGC() != LangOptions::NonGC) {
777 // This is a bit of an hack. We should sort this out by having a proper
778 // CGObjCGNUstep subclass for GC, but we may want to really support the old
779 // ABI and GC added in ObjectiveC2.framework, so we fudge it a bit for now
780 // Get selectors needed in GC mode
781 RetainSel = GetNullarySelector("retain", CGM.getContext());
782 ReleaseSel = GetNullarySelector("release", CGM.getContext());
783 AutoreleaseSel = GetNullarySelector("autorelease", CGM.getContext());
785 // Get functions needed in GC mode
787 // id objc_assign_ivar(id, id, ptrdiff_t);
788 IvarAssignFn.init(&CGM, "objc_assign_ivar", IdTy, IdTy, IdTy, PtrDiffTy,
790 // id objc_assign_strongCast (id, id*)
791 StrongCastAssignFn.init(&CGM, "objc_assign_strongCast", IdTy, IdTy,
793 // id objc_assign_global(id, id*);
794 GlobalAssignFn.init(&CGM, "objc_assign_global", IdTy, IdTy, PtrToIdTy,
796 // id objc_assign_weak(id, id*);
797 WeakAssignFn.init(&CGM, "objc_assign_weak", IdTy, IdTy, PtrToIdTy, NULL);
798 // id objc_read_weak(id*);
799 WeakReadFn.init(&CGM, "objc_read_weak", IdTy, PtrToIdTy, NULL);
800 // void *objc_memmove_collectable(void*, void *, size_t);
801 MemMoveFn.init(&CGM, "objc_memmove_collectable", PtrTy, PtrTy, PtrTy,
806 llvm::Value *CGObjCGNU::GetClassNamed(CGBuilderTy &Builder,
807 const std::string &Name,
809 llvm::Value *ClassName = CGM.GetAddrOfConstantCString(Name);
810 // With the incompatible ABI, this will need to be replaced with a direct
811 // reference to the class symbol. For the compatible nonfragile ABI we are
812 // still performing this lookup at run time but emitting the symbol for the
813 // class externally so that we can make the switch later.
815 // Libobjc2 contains an LLVM pass that replaces calls to objc_lookup_class
816 // with memoized versions or with static references if it's safe to do so.
819 ClassName = Builder.CreateStructGEP(ClassName, 0);
821 llvm::Constant *ClassLookupFn =
822 CGM.CreateRuntimeFunction(llvm::FunctionType::get(IdTy, PtrToInt8Ty, true),
823 "objc_lookup_class");
824 return Builder.CreateCall(ClassLookupFn, ClassName);
827 // This has to perform the lookup every time, since posing and related
828 // techniques can modify the name -> class mapping.
829 llvm::Value *CGObjCGNU::GetClass(CGBuilderTy &Builder,
830 const ObjCInterfaceDecl *OID) {
831 return GetClassNamed(Builder, OID->getNameAsString(), OID->isWeakImported());
833 llvm::Value *CGObjCGNU::EmitNSAutoreleasePoolClassRef(CGBuilderTy &Builder) {
834 return GetClassNamed(Builder, "NSAutoreleasePool", false);
837 llvm::Value *CGObjCGNU::GetSelector(CGBuilderTy &Builder, Selector Sel,
838 const std::string &TypeEncoding, bool lval) {
840 SmallVector<TypedSelector, 2> &Types = SelectorTable[Sel];
841 llvm::GlobalAlias *SelValue = 0;
844 for (SmallVectorImpl<TypedSelector>::iterator i = Types.begin(),
845 e = Types.end() ; i!=e ; i++) {
846 if (i->first == TypeEncoding) {
847 SelValue = i->second;
852 SelValue = new llvm::GlobalAlias(SelectorTy,
853 llvm::GlobalValue::PrivateLinkage,
854 ".objc_selector_"+Sel.getAsString(), NULL,
856 Types.push_back(TypedSelector(TypeEncoding, SelValue));
860 llvm::Value *tmp = Builder.CreateAlloca(SelValue->getType());
861 Builder.CreateStore(SelValue, tmp);
867 llvm::Value *CGObjCGNU::GetSelector(CGBuilderTy &Builder, Selector Sel,
869 return GetSelector(Builder, Sel, std::string(), lval);
872 llvm::Value *CGObjCGNU::GetSelector(CGBuilderTy &Builder, const ObjCMethodDecl
874 std::string SelTypes;
875 CGM.getContext().getObjCEncodingForMethodDecl(Method, SelTypes);
876 return GetSelector(Builder, Method->getSelector(), SelTypes, false);
879 llvm::Constant *CGObjCGNU::GetEHType(QualType T) {
880 if (!CGM.getLangOptions().CPlusPlus) {
881 if (T->isObjCIdType()
882 || T->isObjCQualifiedIdType()) {
883 // With the old ABI, there was only one kind of catchall, which broke
884 // foreign exceptions. With the new ABI, we use __objc_id_typeinfo as
885 // a pointer indicating object catchalls, and NULL to indicate real
887 if (CGM.getLangOptions().ObjCNonFragileABI) {
888 return MakeConstantString("@id");
894 // All other types should be Objective-C interface pointer types.
895 const ObjCObjectPointerType *OPT =
896 T->getAs<ObjCObjectPointerType>();
897 assert(OPT && "Invalid @catch type.");
898 const ObjCInterfaceDecl *IDecl =
899 OPT->getObjectType()->getInterface();
900 assert(IDecl && "Invalid @catch type.");
901 return MakeConstantString(IDecl->getIdentifier()->getName());
903 // For Objective-C++, we want to provide the ability to catch both C++ and
904 // Objective-C objects in the same function.
906 // There's a particular fixed type info for 'id'.
907 if (T->isObjCIdType() ||
908 T->isObjCQualifiedIdType()) {
909 llvm::Constant *IDEHType =
910 CGM.getModule().getGlobalVariable("__objc_id_type_info");
913 new llvm::GlobalVariable(CGM.getModule(), PtrToInt8Ty,
915 llvm::GlobalValue::ExternalLinkage,
916 0, "__objc_id_type_info");
917 return llvm::ConstantExpr::getBitCast(IDEHType, PtrToInt8Ty);
920 const ObjCObjectPointerType *PT =
921 T->getAs<ObjCObjectPointerType>();
922 assert(PT && "Invalid @catch type.");
923 const ObjCInterfaceType *IT = PT->getInterfaceType();
924 assert(IT && "Invalid @catch type.");
925 std::string className = IT->getDecl()->getIdentifier()->getName();
927 std::string typeinfoName = "__objc_eh_typeinfo_" + className;
929 // Return the existing typeinfo if it exists
930 llvm::Constant *typeinfo = TheModule.getGlobalVariable(typeinfoName);
931 if (typeinfo) return typeinfo;
933 // Otherwise create it.
935 // vtable for gnustep::libobjc::__objc_class_type_info
936 // It's quite ugly hard-coding this. Ideally we'd generate it using the host
937 // platform's name mangling.
938 const char *vtableName = "_ZTVN7gnustep7libobjc22__objc_class_type_infoE";
939 llvm::Constant *Vtable = TheModule.getGlobalVariable(vtableName);
941 Vtable = new llvm::GlobalVariable(TheModule, PtrToInt8Ty, true,
942 llvm::GlobalValue::ExternalLinkage, 0, vtableName);
944 llvm::Constant *Two = llvm::ConstantInt::get(IntTy, 2);
945 Vtable = llvm::ConstantExpr::getGetElementPtr(Vtable, Two);
946 Vtable = llvm::ConstantExpr::getBitCast(Vtable, PtrToInt8Ty);
948 llvm::Constant *typeName =
949 ExportUniqueString(className, "__objc_eh_typename_");
951 std::vector<llvm::Constant*> fields;
952 fields.push_back(Vtable);
953 fields.push_back(typeName);
955 MakeGlobal(llvm::StructType::get(PtrToInt8Ty, PtrToInt8Ty,
956 NULL), fields, "__objc_eh_typeinfo_" + className,
957 llvm::GlobalValue::LinkOnceODRLinkage);
958 return llvm::ConstantExpr::getBitCast(TI, PtrToInt8Ty);
961 /// Generate an NSConstantString object.
962 llvm::Constant *CGObjCGNU::GenerateConstantString(const StringLiteral *SL) {
964 std::string Str = SL->getString().str();
966 // Look for an existing one
967 llvm::StringMap<llvm::Constant*>::iterator old = ObjCStrings.find(Str);
968 if (old != ObjCStrings.end())
969 return old->getValue();
971 std::vector<llvm::Constant*> Ivars;
972 Ivars.push_back(NULLPtr);
973 Ivars.push_back(MakeConstantString(Str));
974 Ivars.push_back(llvm::ConstantInt::get(IntTy, Str.size()));
975 llvm::Constant *ObjCStr = MakeGlobal(
976 llvm::StructType::get(PtrToInt8Ty, PtrToInt8Ty, IntTy, NULL),
978 ObjCStr = llvm::ConstantExpr::getBitCast(ObjCStr, PtrToInt8Ty);
979 ObjCStrings[Str] = ObjCStr;
980 ConstantStrings.push_back(ObjCStr);
984 ///Generates a message send where the super is the receiver. This is a message
985 ///send to self with special delivery semantics indicating which class's method
988 CGObjCGNU::GenerateMessageSendSuper(CodeGenFunction &CGF,
989 ReturnValueSlot Return,
992 const ObjCInterfaceDecl *Class,
994 llvm::Value *Receiver,
996 const CallArgList &CallArgs,
997 const ObjCMethodDecl *Method) {
998 CGBuilderTy &Builder = CGF.Builder;
999 if (CGM.getLangOptions().getGC() == LangOptions::GCOnly) {
1000 if (Sel == RetainSel || Sel == AutoreleaseSel) {
1001 return RValue::get(EnforceType(Builder, Receiver,
1002 CGM.getTypes().ConvertType(ResultType)));
1004 if (Sel == ReleaseSel) {
1005 return RValue::get(0);
1009 llvm::Value *cmd = GetSelector(Builder, Sel);
1012 CallArgList ActualArgs;
1014 ActualArgs.add(RValue::get(EnforceType(Builder, Receiver, IdTy)), ASTIdTy);
1015 ActualArgs.add(RValue::get(cmd), CGF.getContext().getObjCSelType());
1016 ActualArgs.addFrom(CallArgs);
1018 CodeGenTypes &Types = CGM.getTypes();
1019 const CGFunctionInfo &FnInfo = Types.getFunctionInfo(ResultType, ActualArgs,
1020 FunctionType::ExtInfo());
1022 llvm::Value *ReceiverClass = 0;
1023 if (isCategoryImpl) {
1024 llvm::Constant *classLookupFunction = 0;
1025 if (IsClassMessage) {
1026 classLookupFunction = CGM.CreateRuntimeFunction(llvm::FunctionType::get(
1027 IdTy, PtrTy, true), "objc_get_meta_class");
1029 classLookupFunction = CGM.CreateRuntimeFunction(llvm::FunctionType::get(
1030 IdTy, PtrTy, true), "objc_get_class");
1032 ReceiverClass = Builder.CreateCall(classLookupFunction,
1033 MakeConstantString(Class->getNameAsString()));
1035 // Set up global aliases for the metaclass or class pointer if they do not
1036 // already exist. These will are forward-references which will be set to
1037 // pointers to the class and metaclass structure created for the runtime
1038 // load function. To send a message to super, we look up the value of the
1039 // super_class pointer from either the class or metaclass structure.
1040 if (IsClassMessage) {
1041 if (!MetaClassPtrAlias) {
1042 MetaClassPtrAlias = new llvm::GlobalAlias(IdTy,
1043 llvm::GlobalValue::InternalLinkage, ".objc_metaclass_ref" +
1044 Class->getNameAsString(), NULL, &TheModule);
1046 ReceiverClass = MetaClassPtrAlias;
1048 if (!ClassPtrAlias) {
1049 ClassPtrAlias = new llvm::GlobalAlias(IdTy,
1050 llvm::GlobalValue::InternalLinkage, ".objc_class_ref" +
1051 Class->getNameAsString(), NULL, &TheModule);
1053 ReceiverClass = ClassPtrAlias;
1056 // Cast the pointer to a simplified version of the class structure
1057 ReceiverClass = Builder.CreateBitCast(ReceiverClass,
1058 llvm::PointerType::getUnqual(
1059 llvm::StructType::get(IdTy, IdTy, NULL)));
1060 // Get the superclass pointer
1061 ReceiverClass = Builder.CreateStructGEP(ReceiverClass, 1);
1062 // Load the superclass pointer
1063 ReceiverClass = Builder.CreateLoad(ReceiverClass);
1064 // Construct the structure used to look up the IMP
1065 llvm::StructType *ObjCSuperTy = llvm::StructType::get(
1066 Receiver->getType(), IdTy, NULL);
1067 llvm::Value *ObjCSuper = Builder.CreateAlloca(ObjCSuperTy);
1069 Builder.CreateStore(Receiver, Builder.CreateStructGEP(ObjCSuper, 0));
1070 Builder.CreateStore(ReceiverClass, Builder.CreateStructGEP(ObjCSuper, 1));
1072 ObjCSuper = EnforceType(Builder, ObjCSuper, PtrToObjCSuperTy);
1073 llvm::FunctionType *impType =
1074 Types.GetFunctionType(FnInfo, Method ? Method->isVariadic() : false);
1077 llvm::Value *imp = LookupIMPSuper(CGF, ObjCSuper, cmd);
1078 imp = EnforceType(Builder, imp, llvm::PointerType::getUnqual(impType));
1080 llvm::Value *impMD[] = {
1081 llvm::MDString::get(VMContext, Sel.getAsString()),
1082 llvm::MDString::get(VMContext, Class->getSuperClass()->getNameAsString()),
1083 llvm::ConstantInt::get(llvm::Type::getInt1Ty(VMContext), IsClassMessage)
1085 llvm::MDNode *node = llvm::MDNode::get(VMContext, impMD);
1087 llvm::Instruction *call;
1088 RValue msgRet = CGF.EmitCall(FnInfo, imp, Return, ActualArgs,
1090 call->setMetadata(msgSendMDKind, node);
1094 /// Generate code for a message send expression.
1096 CGObjCGNU::GenerateMessageSend(CodeGenFunction &CGF,
1097 ReturnValueSlot Return,
1098 QualType ResultType,
1100 llvm::Value *Receiver,
1101 const CallArgList &CallArgs,
1102 const ObjCInterfaceDecl *Class,
1103 const ObjCMethodDecl *Method) {
1104 CGBuilderTy &Builder = CGF.Builder;
1106 // Strip out message sends to retain / release in GC mode
1107 if (CGM.getLangOptions().getGC() == LangOptions::GCOnly) {
1108 if (Sel == RetainSel || Sel == AutoreleaseSel) {
1109 return RValue::get(EnforceType(Builder, Receiver,
1110 CGM.getTypes().ConvertType(ResultType)));
1112 if (Sel == ReleaseSel) {
1113 return RValue::get(0);
1117 // If the return type is something that goes in an integer register, the
1118 // runtime will handle 0 returns. For other cases, we fill in the 0 value
1121 // The language spec says the result of this kind of message send is
1122 // undefined, but lots of people seem to have forgotten to read that
1123 // paragraph and insist on sending messages to nil that have structure
1124 // returns. With GCC, this generates a random return value (whatever happens
1125 // to be on the stack / in those registers at the time) on most platforms,
1126 // and generates an illegal instruction trap on SPARC. With LLVM it corrupts
1128 bool isPointerSizedReturn = (ResultType->isAnyPointerType() ||
1129 ResultType->isIntegralOrEnumerationType() || ResultType->isVoidType());
1131 llvm::BasicBlock *startBB = 0;
1132 llvm::BasicBlock *messageBB = 0;
1133 llvm::BasicBlock *continueBB = 0;
1135 if (!isPointerSizedReturn) {
1136 startBB = Builder.GetInsertBlock();
1137 messageBB = CGF.createBasicBlock("msgSend");
1138 continueBB = CGF.createBasicBlock("continue");
1140 llvm::Value *isNil = Builder.CreateICmpEQ(Receiver,
1141 llvm::Constant::getNullValue(Receiver->getType()));
1142 Builder.CreateCondBr(isNil, continueBB, messageBB);
1143 CGF.EmitBlock(messageBB);
1146 IdTy = cast<llvm::PointerType>(CGM.getTypes().ConvertType(ASTIdTy));
1149 cmd = GetSelector(Builder, Method);
1151 cmd = GetSelector(Builder, Sel);
1152 cmd = EnforceType(Builder, cmd, SelectorTy);
1153 Receiver = EnforceType(Builder, Receiver, IdTy);
1155 llvm::Value *impMD[] = {
1156 llvm::MDString::get(VMContext, Sel.getAsString()),
1157 llvm::MDString::get(VMContext, Class ? Class->getNameAsString() :""),
1158 llvm::ConstantInt::get(llvm::Type::getInt1Ty(VMContext), Class!=0)
1160 llvm::MDNode *node = llvm::MDNode::get(VMContext, impMD);
1162 // Get the IMP to call
1163 llvm::Value *imp = LookupIMP(CGF, Receiver, cmd, node);
1165 CallArgList ActualArgs;
1166 ActualArgs.add(RValue::get(Receiver), ASTIdTy);
1167 ActualArgs.add(RValue::get(cmd), CGF.getContext().getObjCSelType());
1168 ActualArgs.addFrom(CallArgs);
1170 CodeGenTypes &Types = CGM.getTypes();
1171 const CGFunctionInfo &FnInfo = Types.getFunctionInfo(ResultType, ActualArgs,
1172 FunctionType::ExtInfo());
1173 llvm::FunctionType *impType =
1174 Types.GetFunctionType(FnInfo, Method ? Method->isVariadic() : false);
1175 imp = EnforceType(Builder, imp, llvm::PointerType::getUnqual(impType));
1178 // For sender-aware dispatch, we pass the sender as the third argument to a
1179 // lookup function. When sending messages from C code, the sender is nil.
1180 // objc_msg_lookup_sender(id *receiver, SEL selector, id sender);
1181 llvm::Instruction *call;
1182 RValue msgRet = CGF.EmitCall(FnInfo, imp, Return, ActualArgs,
1184 call->setMetadata(msgSendMDKind, node);
1187 if (!isPointerSizedReturn) {
1188 messageBB = CGF.Builder.GetInsertBlock();
1189 CGF.Builder.CreateBr(continueBB);
1190 CGF.EmitBlock(continueBB);
1191 if (msgRet.isScalar()) {
1192 llvm::Value *v = msgRet.getScalarVal();
1193 llvm::PHINode *phi = Builder.CreatePHI(v->getType(), 2);
1194 phi->addIncoming(v, messageBB);
1195 phi->addIncoming(llvm::Constant::getNullValue(v->getType()), startBB);
1196 msgRet = RValue::get(phi);
1197 } else if (msgRet.isAggregate()) {
1198 llvm::Value *v = msgRet.getAggregateAddr();
1199 llvm::PHINode *phi = Builder.CreatePHI(v->getType(), 2);
1200 llvm::PointerType *RetTy = cast<llvm::PointerType>(v->getType());
1201 llvm::AllocaInst *NullVal =
1202 CGF.CreateTempAlloca(RetTy->getElementType(), "null");
1203 CGF.InitTempAlloca(NullVal,
1204 llvm::Constant::getNullValue(RetTy->getElementType()));
1205 phi->addIncoming(v, messageBB);
1206 phi->addIncoming(NullVal, startBB);
1207 msgRet = RValue::getAggregate(phi);
1208 } else /* isComplex() */ {
1209 std::pair<llvm::Value*,llvm::Value*> v = msgRet.getComplexVal();
1210 llvm::PHINode *phi = Builder.CreatePHI(v.first->getType(), 2);
1211 phi->addIncoming(v.first, messageBB);
1212 phi->addIncoming(llvm::Constant::getNullValue(v.first->getType()),
1214 llvm::PHINode *phi2 = Builder.CreatePHI(v.second->getType(), 2);
1215 phi2->addIncoming(v.second, messageBB);
1216 phi2->addIncoming(llvm::Constant::getNullValue(v.second->getType()),
1218 msgRet = RValue::getComplex(phi, phi2);
1224 /// Generates a MethodList. Used in construction of a objc_class and
1225 /// objc_category structures.
1226 llvm::Constant *CGObjCGNU::GenerateMethodList(const StringRef &ClassName,
1227 const StringRef &CategoryName,
1228 const SmallVectorImpl<Selector> &MethodSels,
1229 const SmallVectorImpl<llvm::Constant *> &MethodTypes,
1230 bool isClassMethodList) {
1231 if (MethodSels.empty())
1233 // Get the method structure type.
1234 llvm::StructType *ObjCMethodTy = llvm::StructType::get(
1235 PtrToInt8Ty, // Really a selector, but the runtime creates it us.
1236 PtrToInt8Ty, // Method types
1237 IMPTy, //Method pointer
1239 std::vector<llvm::Constant*> Methods;
1240 std::vector<llvm::Constant*> Elements;
1241 for (unsigned int i = 0, e = MethodTypes.size(); i < e; ++i) {
1243 llvm::Constant *Method =
1244 TheModule.getFunction(SymbolNameForMethod(ClassName, CategoryName,
1246 isClassMethodList));
1247 assert(Method && "Can't generate metadata for method that doesn't exist");
1248 llvm::Constant *C = MakeConstantString(MethodSels[i].getAsString());
1249 Elements.push_back(C);
1250 Elements.push_back(MethodTypes[i]);
1251 Method = llvm::ConstantExpr::getBitCast(Method,
1253 Elements.push_back(Method);
1254 Methods.push_back(llvm::ConstantStruct::get(ObjCMethodTy, Elements));
1257 // Array of method structures
1258 llvm::ArrayType *ObjCMethodArrayTy = llvm::ArrayType::get(ObjCMethodTy,
1260 llvm::Constant *MethodArray = llvm::ConstantArray::get(ObjCMethodArrayTy,
1263 // Structure containing list pointer, array and array count
1264 llvm::StructType *ObjCMethodListTy = llvm::StructType::create(VMContext);
1265 llvm::Type *NextPtrTy = llvm::PointerType::getUnqual(ObjCMethodListTy);
1266 ObjCMethodListTy->setBody(
1273 Methods.push_back(llvm::ConstantPointerNull::get(
1274 llvm::PointerType::getUnqual(ObjCMethodListTy)));
1275 Methods.push_back(llvm::ConstantInt::get(Int32Ty, MethodTypes.size()));
1276 Methods.push_back(MethodArray);
1278 // Create an instance of the structure
1279 return MakeGlobal(ObjCMethodListTy, Methods, ".objc_method_list");
1282 /// Generates an IvarList. Used in construction of a objc_class.
1283 llvm::Constant *CGObjCGNU::GenerateIvarList(
1284 const SmallVectorImpl<llvm::Constant *> &IvarNames,
1285 const SmallVectorImpl<llvm::Constant *> &IvarTypes,
1286 const SmallVectorImpl<llvm::Constant *> &IvarOffsets) {
1287 if (IvarNames.size() == 0)
1289 // Get the method structure type.
1290 llvm::StructType *ObjCIvarTy = llvm::StructType::get(
1295 std::vector<llvm::Constant*> Ivars;
1296 std::vector<llvm::Constant*> Elements;
1297 for (unsigned int i = 0, e = IvarNames.size() ; i < e ; i++) {
1299 Elements.push_back(IvarNames[i]);
1300 Elements.push_back(IvarTypes[i]);
1301 Elements.push_back(IvarOffsets[i]);
1302 Ivars.push_back(llvm::ConstantStruct::get(ObjCIvarTy, Elements));
1305 // Array of method structures
1306 llvm::ArrayType *ObjCIvarArrayTy = llvm::ArrayType::get(ObjCIvarTy,
1311 Elements.push_back(llvm::ConstantInt::get(IntTy, (int)IvarNames.size()));
1312 Elements.push_back(llvm::ConstantArray::get(ObjCIvarArrayTy, Ivars));
1313 // Structure containing array and array count
1314 llvm::StructType *ObjCIvarListTy = llvm::StructType::get(IntTy,
1318 // Create an instance of the structure
1319 return MakeGlobal(ObjCIvarListTy, Elements, ".objc_ivar_list");
1322 /// Generate a class structure
1323 llvm::Constant *CGObjCGNU::GenerateClassStructure(
1324 llvm::Constant *MetaClass,
1325 llvm::Constant *SuperClass,
1328 llvm::Constant *Version,
1329 llvm::Constant *InstanceSize,
1330 llvm::Constant *IVars,
1331 llvm::Constant *Methods,
1332 llvm::Constant *Protocols,
1333 llvm::Constant *IvarOffsets,
1334 llvm::Constant *Properties,
1335 llvm::Constant *StrongIvarBitmap,
1336 llvm::Constant *WeakIvarBitmap,
1338 // Set up the class structure
1339 // Note: Several of these are char*s when they should be ids. This is
1340 // because the runtime performs this translation on load.
1342 // Fields marked New ABI are part of the GNUstep runtime. We emit them
1343 // anyway; the classes will still work with the GNU runtime, they will just
1345 llvm::StructType *ClassTy = llvm::StructType::get(
1346 PtrToInt8Ty, // class_pointer
1347 PtrToInt8Ty, // super_class
1348 PtrToInt8Ty, // name
1351 LongTy, // instance_size
1352 IVars->getType(), // ivars
1353 Methods->getType(), // methods
1354 // These are all filled in by the runtime, so we pretend
1356 PtrTy, // subclass_list
1357 PtrTy, // sibling_class
1359 PtrTy, // gc_object_type
1361 LongTy, // abi_version
1362 IvarOffsets->getType(), // ivar_offsets
1363 Properties->getType(), // properties
1364 Int64Ty, // strong_pointers
1365 Int64Ty, // weak_pointers
1367 llvm::Constant *Zero = llvm::ConstantInt::get(LongTy, 0);
1368 // Fill in the structure
1369 std::vector<llvm::Constant*> Elements;
1370 Elements.push_back(llvm::ConstantExpr::getBitCast(MetaClass, PtrToInt8Ty));
1371 Elements.push_back(SuperClass);
1372 Elements.push_back(MakeConstantString(Name, ".class_name"));
1373 Elements.push_back(Zero);
1374 Elements.push_back(llvm::ConstantInt::get(LongTy, info));
1376 llvm::TargetData td(&TheModule);
1378 llvm::ConstantInt::get(LongTy,
1379 td.getTypeSizeInBits(ClassTy) /
1380 CGM.getContext().getCharWidth()));
1382 Elements.push_back(InstanceSize);
1383 Elements.push_back(IVars);
1384 Elements.push_back(Methods);
1385 Elements.push_back(NULLPtr);
1386 Elements.push_back(NULLPtr);
1387 Elements.push_back(NULLPtr);
1388 Elements.push_back(llvm::ConstantExpr::getBitCast(Protocols, PtrTy));
1389 Elements.push_back(NULLPtr);
1390 Elements.push_back(llvm::ConstantInt::get(LongTy, 1));
1391 Elements.push_back(IvarOffsets);
1392 Elements.push_back(Properties);
1393 Elements.push_back(StrongIvarBitmap);
1394 Elements.push_back(WeakIvarBitmap);
1395 // Create an instance of the structure
1396 // This is now an externally visible symbol, so that we can speed up class
1397 // messages in the next ABI.
1398 return MakeGlobal(ClassTy, Elements, (isMeta ? "_OBJC_METACLASS_":
1399 "_OBJC_CLASS_") + std::string(Name), llvm::GlobalValue::ExternalLinkage);
1402 llvm::Constant *CGObjCGNU::GenerateProtocolMethodList(
1403 const SmallVectorImpl<llvm::Constant *> &MethodNames,
1404 const SmallVectorImpl<llvm::Constant *> &MethodTypes) {
1405 // Get the method structure type.
1406 llvm::StructType *ObjCMethodDescTy = llvm::StructType::get(
1407 PtrToInt8Ty, // Really a selector, but the runtime does the casting for us.
1410 std::vector<llvm::Constant*> Methods;
1411 std::vector<llvm::Constant*> Elements;
1412 for (unsigned int i = 0, e = MethodTypes.size() ; i < e ; i++) {
1414 Elements.push_back(MethodNames[i]);
1415 Elements.push_back(MethodTypes[i]);
1416 Methods.push_back(llvm::ConstantStruct::get(ObjCMethodDescTy, Elements));
1418 llvm::ArrayType *ObjCMethodArrayTy = llvm::ArrayType::get(ObjCMethodDescTy,
1419 MethodNames.size());
1420 llvm::Constant *Array = llvm::ConstantArray::get(ObjCMethodArrayTy,
1422 llvm::StructType *ObjCMethodDescListTy = llvm::StructType::get(
1423 IntTy, ObjCMethodArrayTy, NULL);
1425 Methods.push_back(llvm::ConstantInt::get(IntTy, MethodNames.size()));
1426 Methods.push_back(Array);
1427 return MakeGlobal(ObjCMethodDescListTy, Methods, ".objc_method_list");
1430 // Create the protocol list structure used in classes, categories and so on
1431 llvm::Constant *CGObjCGNU::GenerateProtocolList(
1432 const SmallVectorImpl<std::string> &Protocols) {
1433 llvm::ArrayType *ProtocolArrayTy = llvm::ArrayType::get(PtrToInt8Ty,
1435 llvm::StructType *ProtocolListTy = llvm::StructType::get(
1436 PtrTy, //Should be a recurisve pointer, but it's always NULL here.
1440 std::vector<llvm::Constant*> Elements;
1441 for (const std::string *iter = Protocols.begin(), *endIter = Protocols.end();
1442 iter != endIter ; iter++) {
1443 llvm::Constant *protocol = 0;
1444 llvm::StringMap<llvm::Constant*>::iterator value =
1445 ExistingProtocols.find(*iter);
1446 if (value == ExistingProtocols.end()) {
1447 protocol = GenerateEmptyProtocol(*iter);
1449 protocol = value->getValue();
1451 llvm::Constant *Ptr = llvm::ConstantExpr::getBitCast(protocol,
1453 Elements.push_back(Ptr);
1455 llvm::Constant * ProtocolArray = llvm::ConstantArray::get(ProtocolArrayTy,
1458 Elements.push_back(NULLPtr);
1459 Elements.push_back(llvm::ConstantInt::get(LongTy, Protocols.size()));
1460 Elements.push_back(ProtocolArray);
1461 return MakeGlobal(ProtocolListTy, Elements, ".objc_protocol_list");
1464 llvm::Value *CGObjCGNU::GenerateProtocolRef(CGBuilderTy &Builder,
1465 const ObjCProtocolDecl *PD) {
1466 llvm::Value *protocol = ExistingProtocols[PD->getNameAsString()];
1468 CGM.getTypes().ConvertType(CGM.getContext().getObjCProtoType());
1469 return Builder.CreateBitCast(protocol, llvm::PointerType::getUnqual(T));
1472 llvm::Constant *CGObjCGNU::GenerateEmptyProtocol(
1473 const std::string &ProtocolName) {
1474 SmallVector<std::string, 0> EmptyStringVector;
1475 SmallVector<llvm::Constant*, 0> EmptyConstantVector;
1477 llvm::Constant *ProtocolList = GenerateProtocolList(EmptyStringVector);
1478 llvm::Constant *MethodList =
1479 GenerateProtocolMethodList(EmptyConstantVector, EmptyConstantVector);
1480 // Protocols are objects containing lists of the methods implemented and
1481 // protocols adopted.
1482 llvm::StructType *ProtocolTy = llvm::StructType::get(IdTy,
1484 ProtocolList->getType(),
1485 MethodList->getType(),
1486 MethodList->getType(),
1487 MethodList->getType(),
1488 MethodList->getType(),
1490 std::vector<llvm::Constant*> Elements;
1491 // The isa pointer must be set to a magic number so the runtime knows it's
1492 // the correct layout.
1493 Elements.push_back(llvm::ConstantExpr::getIntToPtr(
1494 llvm::ConstantInt::get(Int32Ty, ProtocolVersion), IdTy));
1495 Elements.push_back(MakeConstantString(ProtocolName, ".objc_protocol_name"));
1496 Elements.push_back(ProtocolList);
1497 Elements.push_back(MethodList);
1498 Elements.push_back(MethodList);
1499 Elements.push_back(MethodList);
1500 Elements.push_back(MethodList);
1501 return MakeGlobal(ProtocolTy, Elements, ".objc_protocol");
1504 void CGObjCGNU::GenerateProtocol(const ObjCProtocolDecl *PD) {
1505 ASTContext &Context = CGM.getContext();
1506 std::string ProtocolName = PD->getNameAsString();
1507 SmallVector<std::string, 16> Protocols;
1508 for (ObjCProtocolDecl::protocol_iterator PI = PD->protocol_begin(),
1509 E = PD->protocol_end(); PI != E; ++PI)
1510 Protocols.push_back((*PI)->getNameAsString());
1511 SmallVector<llvm::Constant*, 16> InstanceMethodNames;
1512 SmallVector<llvm::Constant*, 16> InstanceMethodTypes;
1513 SmallVector<llvm::Constant*, 16> OptionalInstanceMethodNames;
1514 SmallVector<llvm::Constant*, 16> OptionalInstanceMethodTypes;
1515 for (ObjCProtocolDecl::instmeth_iterator iter = PD->instmeth_begin(),
1516 E = PD->instmeth_end(); iter != E; iter++) {
1517 std::string TypeStr;
1518 Context.getObjCEncodingForMethodDecl(*iter, TypeStr);
1519 if ((*iter)->getImplementationControl() == ObjCMethodDecl::Optional) {
1520 InstanceMethodNames.push_back(
1521 MakeConstantString((*iter)->getSelector().getAsString()));
1522 InstanceMethodTypes.push_back(MakeConstantString(TypeStr));
1524 OptionalInstanceMethodNames.push_back(
1525 MakeConstantString((*iter)->getSelector().getAsString()));
1526 OptionalInstanceMethodTypes.push_back(MakeConstantString(TypeStr));
1529 // Collect information about class methods:
1530 SmallVector<llvm::Constant*, 16> ClassMethodNames;
1531 SmallVector<llvm::Constant*, 16> ClassMethodTypes;
1532 SmallVector<llvm::Constant*, 16> OptionalClassMethodNames;
1533 SmallVector<llvm::Constant*, 16> OptionalClassMethodTypes;
1534 for (ObjCProtocolDecl::classmeth_iterator
1535 iter = PD->classmeth_begin(), endIter = PD->classmeth_end();
1536 iter != endIter ; iter++) {
1537 std::string TypeStr;
1538 Context.getObjCEncodingForMethodDecl((*iter),TypeStr);
1539 if ((*iter)->getImplementationControl() == ObjCMethodDecl::Optional) {
1540 ClassMethodNames.push_back(
1541 MakeConstantString((*iter)->getSelector().getAsString()));
1542 ClassMethodTypes.push_back(MakeConstantString(TypeStr));
1544 OptionalClassMethodNames.push_back(
1545 MakeConstantString((*iter)->getSelector().getAsString()));
1546 OptionalClassMethodTypes.push_back(MakeConstantString(TypeStr));
1550 llvm::Constant *ProtocolList = GenerateProtocolList(Protocols);
1551 llvm::Constant *InstanceMethodList =
1552 GenerateProtocolMethodList(InstanceMethodNames, InstanceMethodTypes);
1553 llvm::Constant *ClassMethodList =
1554 GenerateProtocolMethodList(ClassMethodNames, ClassMethodTypes);
1555 llvm::Constant *OptionalInstanceMethodList =
1556 GenerateProtocolMethodList(OptionalInstanceMethodNames,
1557 OptionalInstanceMethodTypes);
1558 llvm::Constant *OptionalClassMethodList =
1559 GenerateProtocolMethodList(OptionalClassMethodNames,
1560 OptionalClassMethodTypes);
1562 // Property metadata: name, attributes, isSynthesized, setter name, setter
1563 // types, getter name, getter types.
1564 // The isSynthesized value is always set to 0 in a protocol. It exists to
1565 // simplify the runtime library by allowing it to use the same data
1566 // structures for protocol metadata everywhere.
1567 llvm::StructType *PropertyMetadataTy = llvm::StructType::get(
1568 PtrToInt8Ty, Int8Ty, Int8Ty, PtrToInt8Ty, PtrToInt8Ty, PtrToInt8Ty,
1570 std::vector<llvm::Constant*> Properties;
1571 std::vector<llvm::Constant*> OptionalProperties;
1573 // Add all of the property methods need adding to the method list and to the
1574 // property metadata list.
1575 for (ObjCContainerDecl::prop_iterator
1576 iter = PD->prop_begin(), endIter = PD->prop_end();
1577 iter != endIter ; iter++) {
1578 std::vector<llvm::Constant*> Fields;
1579 ObjCPropertyDecl *property = (*iter);
1581 Fields.push_back(MakeConstantString(property->getNameAsString()));
1582 Fields.push_back(llvm::ConstantInt::get(Int8Ty,
1583 property->getPropertyAttributes()));
1584 Fields.push_back(llvm::ConstantInt::get(Int8Ty, 0));
1585 if (ObjCMethodDecl *getter = property->getGetterMethodDecl()) {
1586 std::string TypeStr;
1587 Context.getObjCEncodingForMethodDecl(getter,TypeStr);
1588 llvm::Constant *TypeEncoding = MakeConstantString(TypeStr);
1589 InstanceMethodTypes.push_back(TypeEncoding);
1590 Fields.push_back(MakeConstantString(getter->getSelector().getAsString()));
1591 Fields.push_back(TypeEncoding);
1593 Fields.push_back(NULLPtr);
1594 Fields.push_back(NULLPtr);
1596 if (ObjCMethodDecl *setter = property->getSetterMethodDecl()) {
1597 std::string TypeStr;
1598 Context.getObjCEncodingForMethodDecl(setter,TypeStr);
1599 llvm::Constant *TypeEncoding = MakeConstantString(TypeStr);
1600 InstanceMethodTypes.push_back(TypeEncoding);
1601 Fields.push_back(MakeConstantString(setter->getSelector().getAsString()));
1602 Fields.push_back(TypeEncoding);
1604 Fields.push_back(NULLPtr);
1605 Fields.push_back(NULLPtr);
1607 if (property->getPropertyImplementation() == ObjCPropertyDecl::Optional) {
1608 OptionalProperties.push_back(llvm::ConstantStruct::get(PropertyMetadataTy, Fields));
1610 Properties.push_back(llvm::ConstantStruct::get(PropertyMetadataTy, Fields));
1613 llvm::Constant *PropertyArray = llvm::ConstantArray::get(
1614 llvm::ArrayType::get(PropertyMetadataTy, Properties.size()), Properties);
1615 llvm::Constant* PropertyListInitFields[] =
1616 {llvm::ConstantInt::get(IntTy, Properties.size()), NULLPtr, PropertyArray};
1618 llvm::Constant *PropertyListInit =
1619 llvm::ConstantStruct::getAnon(PropertyListInitFields);
1620 llvm::Constant *PropertyList = new llvm::GlobalVariable(TheModule,
1621 PropertyListInit->getType(), false, llvm::GlobalValue::InternalLinkage,
1622 PropertyListInit, ".objc_property_list");
1624 llvm::Constant *OptionalPropertyArray =
1625 llvm::ConstantArray::get(llvm::ArrayType::get(PropertyMetadataTy,
1626 OptionalProperties.size()) , OptionalProperties);
1627 llvm::Constant* OptionalPropertyListInitFields[] = {
1628 llvm::ConstantInt::get(IntTy, OptionalProperties.size()), NULLPtr,
1629 OptionalPropertyArray };
1631 llvm::Constant *OptionalPropertyListInit =
1632 llvm::ConstantStruct::getAnon(OptionalPropertyListInitFields);
1633 llvm::Constant *OptionalPropertyList = new llvm::GlobalVariable(TheModule,
1634 OptionalPropertyListInit->getType(), false,
1635 llvm::GlobalValue::InternalLinkage, OptionalPropertyListInit,
1636 ".objc_property_list");
1638 // Protocols are objects containing lists of the methods implemented and
1639 // protocols adopted.
1640 llvm::StructType *ProtocolTy = llvm::StructType::get(IdTy,
1642 ProtocolList->getType(),
1643 InstanceMethodList->getType(),
1644 ClassMethodList->getType(),
1645 OptionalInstanceMethodList->getType(),
1646 OptionalClassMethodList->getType(),
1647 PropertyList->getType(),
1648 OptionalPropertyList->getType(),
1650 std::vector<llvm::Constant*> Elements;
1651 // The isa pointer must be set to a magic number so the runtime knows it's
1652 // the correct layout.
1653 Elements.push_back(llvm::ConstantExpr::getIntToPtr(
1654 llvm::ConstantInt::get(Int32Ty, ProtocolVersion), IdTy));
1655 Elements.push_back(MakeConstantString(ProtocolName, ".objc_protocol_name"));
1656 Elements.push_back(ProtocolList);
1657 Elements.push_back(InstanceMethodList);
1658 Elements.push_back(ClassMethodList);
1659 Elements.push_back(OptionalInstanceMethodList);
1660 Elements.push_back(OptionalClassMethodList);
1661 Elements.push_back(PropertyList);
1662 Elements.push_back(OptionalPropertyList);
1663 ExistingProtocols[ProtocolName] =
1664 llvm::ConstantExpr::getBitCast(MakeGlobal(ProtocolTy, Elements,
1665 ".objc_protocol"), IdTy);
1667 void CGObjCGNU::GenerateProtocolHolderCategory(void) {
1668 // Collect information about instance methods
1669 SmallVector<Selector, 1> MethodSels;
1670 SmallVector<llvm::Constant*, 1> MethodTypes;
1672 std::vector<llvm::Constant*> Elements;
1673 const std::string ClassName = "__ObjC_Protocol_Holder_Ugly_Hack";
1674 const std::string CategoryName = "AnotherHack";
1675 Elements.push_back(MakeConstantString(CategoryName));
1676 Elements.push_back(MakeConstantString(ClassName));
1677 // Instance method list
1678 Elements.push_back(llvm::ConstantExpr::getBitCast(GenerateMethodList(
1679 ClassName, CategoryName, MethodSels, MethodTypes, false), PtrTy));
1680 // Class method list
1681 Elements.push_back(llvm::ConstantExpr::getBitCast(GenerateMethodList(
1682 ClassName, CategoryName, MethodSels, MethodTypes, true), PtrTy));
1684 llvm::ArrayType *ProtocolArrayTy = llvm::ArrayType::get(PtrTy,
1685 ExistingProtocols.size());
1686 llvm::StructType *ProtocolListTy = llvm::StructType::get(
1687 PtrTy, //Should be a recurisve pointer, but it's always NULL here.
1691 std::vector<llvm::Constant*> ProtocolElements;
1692 for (llvm::StringMapIterator<llvm::Constant*> iter =
1693 ExistingProtocols.begin(), endIter = ExistingProtocols.end();
1694 iter != endIter ; iter++) {
1695 llvm::Constant *Ptr = llvm::ConstantExpr::getBitCast(iter->getValue(),
1697 ProtocolElements.push_back(Ptr);
1699 llvm::Constant * ProtocolArray = llvm::ConstantArray::get(ProtocolArrayTy,
1701 ProtocolElements.clear();
1702 ProtocolElements.push_back(NULLPtr);
1703 ProtocolElements.push_back(llvm::ConstantInt::get(LongTy,
1704 ExistingProtocols.size()));
1705 ProtocolElements.push_back(ProtocolArray);
1706 Elements.push_back(llvm::ConstantExpr::getBitCast(MakeGlobal(ProtocolListTy,
1707 ProtocolElements, ".objc_protocol_list"), PtrTy));
1708 Categories.push_back(llvm::ConstantExpr::getBitCast(
1709 MakeGlobal(llvm::StructType::get(PtrToInt8Ty, PtrToInt8Ty,
1710 PtrTy, PtrTy, PtrTy, NULL), Elements), PtrTy));
1713 /// Libobjc2 uses a bitfield representation where small(ish) bitfields are
1714 /// stored in a 64-bit value with the low bit set to 1 and the remaining 63
1715 /// bits set to their values, LSB first, while larger ones are stored in a
1716 /// structure of this / form:
1718 /// struct { int32_t length; int32_t values[length]; };
1720 /// The values in the array are stored in host-endian format, with the least
1721 /// significant bit being assumed to come first in the bitfield. Therefore, a
1722 /// bitfield with the 64th bit set will be (int64_t)&{ 2, [0, 1<<31] }, while a
1723 /// bitfield / with the 63rd bit set will be 1<<64.
1724 llvm::Constant *CGObjCGNU::MakeBitField(llvm::SmallVectorImpl<bool> &bits) {
1725 int bitCount = bits.size();
1726 if (bitCount < 64) {
1728 for (int i=0 ; i<bitCount ; ++i) {
1729 if (bits[i]) val |= 1ULL<<(i+1);
1731 return llvm::ConstantInt::get(Int64Ty, val);
1733 llvm::SmallVector<llvm::Constant*, 8> values;
1735 while (v < bitCount) {
1737 for (int i=0 ; (i<32) && (v<bitCount) ; ++i) {
1738 if (bits[v]) word |= 1<<i;
1741 values.push_back(llvm::ConstantInt::get(Int32Ty, word));
1743 llvm::ArrayType *arrayTy = llvm::ArrayType::get(Int32Ty, values.size());
1744 llvm::Constant *array = llvm::ConstantArray::get(arrayTy, values);
1745 llvm::Constant *fields[2] = {
1746 llvm::ConstantInt::get(Int32Ty, values.size()),
1748 llvm::Constant *GS = MakeGlobal(llvm::StructType::get(Int32Ty, arrayTy,
1750 llvm::Constant *ptr = llvm::ConstantExpr::getPtrToInt(GS, IntPtrTy);
1751 if (IntPtrTy != Int64Ty)
1752 ptr = llvm::ConstantExpr::getZExt(ptr, Int64Ty);
1756 void CGObjCGNU::GenerateCategory(const ObjCCategoryImplDecl *OCD) {
1757 std::string ClassName = OCD->getClassInterface()->getNameAsString();
1758 std::string CategoryName = OCD->getNameAsString();
1759 // Collect information about instance methods
1760 SmallVector<Selector, 16> InstanceMethodSels;
1761 SmallVector<llvm::Constant*, 16> InstanceMethodTypes;
1762 for (ObjCCategoryImplDecl::instmeth_iterator
1763 iter = OCD->instmeth_begin(), endIter = OCD->instmeth_end();
1764 iter != endIter ; iter++) {
1765 InstanceMethodSels.push_back((*iter)->getSelector());
1766 std::string TypeStr;
1767 CGM.getContext().getObjCEncodingForMethodDecl(*iter,TypeStr);
1768 InstanceMethodTypes.push_back(MakeConstantString(TypeStr));
1771 // Collect information about class methods
1772 SmallVector<Selector, 16> ClassMethodSels;
1773 SmallVector<llvm::Constant*, 16> ClassMethodTypes;
1774 for (ObjCCategoryImplDecl::classmeth_iterator
1775 iter = OCD->classmeth_begin(), endIter = OCD->classmeth_end();
1776 iter != endIter ; iter++) {
1777 ClassMethodSels.push_back((*iter)->getSelector());
1778 std::string TypeStr;
1779 CGM.getContext().getObjCEncodingForMethodDecl(*iter,TypeStr);
1780 ClassMethodTypes.push_back(MakeConstantString(TypeStr));
1783 // Collect the names of referenced protocols
1784 SmallVector<std::string, 16> Protocols;
1785 const ObjCCategoryDecl *CatDecl = OCD->getCategoryDecl();
1786 const ObjCList<ObjCProtocolDecl> &Protos = CatDecl->getReferencedProtocols();
1787 for (ObjCList<ObjCProtocolDecl>::iterator I = Protos.begin(),
1788 E = Protos.end(); I != E; ++I)
1789 Protocols.push_back((*I)->getNameAsString());
1791 std::vector<llvm::Constant*> Elements;
1792 Elements.push_back(MakeConstantString(CategoryName));
1793 Elements.push_back(MakeConstantString(ClassName));
1794 // Instance method list
1795 Elements.push_back(llvm::ConstantExpr::getBitCast(GenerateMethodList(
1796 ClassName, CategoryName, InstanceMethodSels, InstanceMethodTypes,
1798 // Class method list
1799 Elements.push_back(llvm::ConstantExpr::getBitCast(GenerateMethodList(
1800 ClassName, CategoryName, ClassMethodSels, ClassMethodTypes, true),
1803 Elements.push_back(llvm::ConstantExpr::getBitCast(
1804 GenerateProtocolList(Protocols), PtrTy));
1805 Categories.push_back(llvm::ConstantExpr::getBitCast(
1806 MakeGlobal(llvm::StructType::get(PtrToInt8Ty, PtrToInt8Ty,
1807 PtrTy, PtrTy, PtrTy, NULL), Elements), PtrTy));
1810 llvm::Constant *CGObjCGNU::GeneratePropertyList(const ObjCImplementationDecl *OID,
1811 SmallVectorImpl<Selector> &InstanceMethodSels,
1812 SmallVectorImpl<llvm::Constant*> &InstanceMethodTypes) {
1813 ASTContext &Context = CGM.getContext();
1815 // Property metadata: name, attributes, isSynthesized, setter name, setter
1816 // types, getter name, getter types.
1817 llvm::StructType *PropertyMetadataTy = llvm::StructType::get(
1818 PtrToInt8Ty, Int8Ty, Int8Ty, PtrToInt8Ty, PtrToInt8Ty, PtrToInt8Ty,
1820 std::vector<llvm::Constant*> Properties;
1823 // Add all of the property methods need adding to the method list and to the
1824 // property metadata list.
1825 for (ObjCImplDecl::propimpl_iterator
1826 iter = OID->propimpl_begin(), endIter = OID->propimpl_end();
1827 iter != endIter ; iter++) {
1828 std::vector<llvm::Constant*> Fields;
1829 ObjCPropertyDecl *property = (*iter)->getPropertyDecl();
1830 ObjCPropertyImplDecl *propertyImpl = *iter;
1831 bool isSynthesized = (propertyImpl->getPropertyImplementation() ==
1832 ObjCPropertyImplDecl::Synthesize);
1834 Fields.push_back(MakeConstantString(property->getNameAsString()));
1835 Fields.push_back(llvm::ConstantInt::get(Int8Ty,
1836 property->getPropertyAttributes()));
1837 Fields.push_back(llvm::ConstantInt::get(Int8Ty, isSynthesized));
1838 if (ObjCMethodDecl *getter = property->getGetterMethodDecl()) {
1839 std::string TypeStr;
1840 Context.getObjCEncodingForMethodDecl(getter,TypeStr);
1841 llvm::Constant *TypeEncoding = MakeConstantString(TypeStr);
1842 if (isSynthesized) {
1843 InstanceMethodTypes.push_back(TypeEncoding);
1844 InstanceMethodSels.push_back(getter->getSelector());
1846 Fields.push_back(MakeConstantString(getter->getSelector().getAsString()));
1847 Fields.push_back(TypeEncoding);
1849 Fields.push_back(NULLPtr);
1850 Fields.push_back(NULLPtr);
1852 if (ObjCMethodDecl *setter = property->getSetterMethodDecl()) {
1853 std::string TypeStr;
1854 Context.getObjCEncodingForMethodDecl(setter,TypeStr);
1855 llvm::Constant *TypeEncoding = MakeConstantString(TypeStr);
1856 if (isSynthesized) {
1857 InstanceMethodTypes.push_back(TypeEncoding);
1858 InstanceMethodSels.push_back(setter->getSelector());
1860 Fields.push_back(MakeConstantString(setter->getSelector().getAsString()));
1861 Fields.push_back(TypeEncoding);
1863 Fields.push_back(NULLPtr);
1864 Fields.push_back(NULLPtr);
1866 Properties.push_back(llvm::ConstantStruct::get(PropertyMetadataTy, Fields));
1868 llvm::ArrayType *PropertyArrayTy =
1869 llvm::ArrayType::get(PropertyMetadataTy, Properties.size());
1870 llvm::Constant *PropertyArray = llvm::ConstantArray::get(PropertyArrayTy,
1872 llvm::Constant* PropertyListInitFields[] =
1873 {llvm::ConstantInt::get(IntTy, Properties.size()), NULLPtr, PropertyArray};
1875 llvm::Constant *PropertyListInit =
1876 llvm::ConstantStruct::getAnon(PropertyListInitFields);
1877 return new llvm::GlobalVariable(TheModule, PropertyListInit->getType(), false,
1878 llvm::GlobalValue::InternalLinkage, PropertyListInit,
1879 ".objc_property_list");
1882 void CGObjCGNU::GenerateClass(const ObjCImplementationDecl *OID) {
1883 ASTContext &Context = CGM.getContext();
1885 // Get the superclass name.
1886 const ObjCInterfaceDecl * SuperClassDecl =
1887 OID->getClassInterface()->getSuperClass();
1888 std::string SuperClassName;
1889 if (SuperClassDecl) {
1890 SuperClassName = SuperClassDecl->getNameAsString();
1891 EmitClassRef(SuperClassName);
1894 // Get the class name
1895 ObjCInterfaceDecl *ClassDecl =
1896 const_cast<ObjCInterfaceDecl *>(OID->getClassInterface());
1897 std::string ClassName = ClassDecl->getNameAsString();
1898 // Emit the symbol that is used to generate linker errors if this class is
1899 // referenced in other modules but not declared.
1900 std::string classSymbolName = "__objc_class_name_" + ClassName;
1901 if (llvm::GlobalVariable *symbol =
1902 TheModule.getGlobalVariable(classSymbolName)) {
1903 symbol->setInitializer(llvm::ConstantInt::get(LongTy, 0));
1905 new llvm::GlobalVariable(TheModule, LongTy, false,
1906 llvm::GlobalValue::ExternalLinkage, llvm::ConstantInt::get(LongTy, 0),
1910 // Get the size of instances.
1912 Context.getASTObjCImplementationLayout(OID).getSize().getQuantity();
1914 // Collect information about instance variables.
1915 SmallVector<llvm::Constant*, 16> IvarNames;
1916 SmallVector<llvm::Constant*, 16> IvarTypes;
1917 SmallVector<llvm::Constant*, 16> IvarOffsets;
1919 std::vector<llvm::Constant*> IvarOffsetValues;
1920 SmallVector<bool, 16> WeakIvars;
1921 SmallVector<bool, 16> StrongIvars;
1923 int superInstanceSize = !SuperClassDecl ? 0 :
1924 Context.getASTObjCInterfaceLayout(SuperClassDecl).getSize().getQuantity();
1925 // For non-fragile ivars, set the instance size to 0 - {the size of just this
1926 // class}. The runtime will then set this to the correct value on load.
1927 if (CGM.getContext().getLangOptions().ObjCNonFragileABI) {
1928 instanceSize = 0 - (instanceSize - superInstanceSize);
1931 for (const ObjCIvarDecl *IVD = ClassDecl->all_declared_ivar_begin(); IVD;
1932 IVD = IVD->getNextIvar()) {
1934 IvarNames.push_back(MakeConstantString(IVD->getNameAsString()));
1935 // Get the type encoding for this ivar
1936 std::string TypeStr;
1937 Context.getObjCEncodingForType(IVD->getType(), TypeStr);
1938 IvarTypes.push_back(MakeConstantString(TypeStr));
1940 uint64_t BaseOffset = ComputeIvarBaseOffset(CGM, OID, IVD);
1941 uint64_t Offset = BaseOffset;
1942 if (CGM.getContext().getLangOptions().ObjCNonFragileABI) {
1943 Offset = BaseOffset - superInstanceSize;
1945 llvm::Constant *OffsetValue = llvm::ConstantInt::get(IntTy, Offset);
1946 // Create the direct offset value
1947 std::string OffsetName = "__objc_ivar_offset_value_" + ClassName +"." +
1948 IVD->getNameAsString();
1949 llvm::GlobalVariable *OffsetVar = TheModule.getGlobalVariable(OffsetName);
1951 OffsetVar->setInitializer(OffsetValue);
1952 // If this is the real definition, change its linkage type so that
1953 // different modules will use this one, rather than their private
1955 OffsetVar->setLinkage(llvm::GlobalValue::ExternalLinkage);
1957 OffsetVar = new llvm::GlobalVariable(TheModule, IntTy,
1958 false, llvm::GlobalValue::ExternalLinkage,
1960 "__objc_ivar_offset_value_" + ClassName +"." +
1961 IVD->getNameAsString());
1962 IvarOffsets.push_back(OffsetValue);
1963 IvarOffsetValues.push_back(OffsetVar);
1964 Qualifiers::ObjCLifetime lt = IVD->getType().getQualifiers().getObjCLifetime();
1966 case Qualifiers::OCL_Strong:
1967 StrongIvars.push_back(true);
1968 WeakIvars.push_back(false);
1970 case Qualifiers::OCL_Weak:
1971 StrongIvars.push_back(false);
1972 WeakIvars.push_back(true);
1975 StrongIvars.push_back(false);
1976 WeakIvars.push_back(false);
1979 llvm::Constant *StrongIvarBitmap = MakeBitField(StrongIvars);
1980 llvm::Constant *WeakIvarBitmap = MakeBitField(WeakIvars);
1981 llvm::GlobalVariable *IvarOffsetArray =
1982 MakeGlobalArray(PtrToIntTy, IvarOffsetValues, ".ivar.offsets");
1985 // Collect information about instance methods
1986 SmallVector<Selector, 16> InstanceMethodSels;
1987 SmallVector<llvm::Constant*, 16> InstanceMethodTypes;
1988 for (ObjCImplementationDecl::instmeth_iterator
1989 iter = OID->instmeth_begin(), endIter = OID->instmeth_end();
1990 iter != endIter ; iter++) {
1991 InstanceMethodSels.push_back((*iter)->getSelector());
1992 std::string TypeStr;
1993 Context.getObjCEncodingForMethodDecl((*iter),TypeStr);
1994 InstanceMethodTypes.push_back(MakeConstantString(TypeStr));
1997 llvm::Constant *Properties = GeneratePropertyList(OID, InstanceMethodSels,
1998 InstanceMethodTypes);
2001 // Collect information about class methods
2002 SmallVector<Selector, 16> ClassMethodSels;
2003 SmallVector<llvm::Constant*, 16> ClassMethodTypes;
2004 for (ObjCImplementationDecl::classmeth_iterator
2005 iter = OID->classmeth_begin(), endIter = OID->classmeth_end();
2006 iter != endIter ; iter++) {
2007 ClassMethodSels.push_back((*iter)->getSelector());
2008 std::string TypeStr;
2009 Context.getObjCEncodingForMethodDecl((*iter),TypeStr);
2010 ClassMethodTypes.push_back(MakeConstantString(TypeStr));
2012 // Collect the names of referenced protocols
2013 SmallVector<std::string, 16> Protocols;
2014 const ObjCList<ObjCProtocolDecl> &Protos =ClassDecl->getReferencedProtocols();
2015 for (ObjCList<ObjCProtocolDecl>::iterator I = Protos.begin(),
2016 E = Protos.end(); I != E; ++I)
2017 Protocols.push_back((*I)->getNameAsString());
2021 // Get the superclass pointer.
2022 llvm::Constant *SuperClass;
2023 if (!SuperClassName.empty()) {
2024 SuperClass = MakeConstantString(SuperClassName, ".super_class_name");
2026 SuperClass = llvm::ConstantPointerNull::get(PtrToInt8Ty);
2028 // Empty vector used to construct empty method lists
2029 SmallVector<llvm::Constant*, 1> empty;
2030 // Generate the method and instance variable lists
2031 llvm::Constant *MethodList = GenerateMethodList(ClassName, "",
2032 InstanceMethodSels, InstanceMethodTypes, false);
2033 llvm::Constant *ClassMethodList = GenerateMethodList(ClassName, "",
2034 ClassMethodSels, ClassMethodTypes, true);
2035 llvm::Constant *IvarList = GenerateIvarList(IvarNames, IvarTypes,
2037 // Irrespective of whether we are compiling for a fragile or non-fragile ABI,
2038 // we emit a symbol containing the offset for each ivar in the class. This
2039 // allows code compiled for the non-Fragile ABI to inherit from code compiled
2040 // for the legacy ABI, without causing problems. The converse is also
2041 // possible, but causes all ivar accesses to be fragile.
2043 // Offset pointer for getting at the correct field in the ivar list when
2044 // setting up the alias. These are: The base address for the global, the
2045 // ivar array (second field), the ivar in this list (set for each ivar), and
2046 // the offset (third field in ivar structure)
2047 llvm::Type *IndexTy = Int32Ty;
2048 llvm::Constant *offsetPointerIndexes[] = {Zeros[0],
2049 llvm::ConstantInt::get(IndexTy, 1), 0,
2050 llvm::ConstantInt::get(IndexTy, 2) };
2052 unsigned ivarIndex = 0;
2053 for (const ObjCIvarDecl *IVD = ClassDecl->all_declared_ivar_begin(); IVD;
2054 IVD = IVD->getNextIvar()) {
2055 const std::string Name = "__objc_ivar_offset_" + ClassName + '.'
2056 + IVD->getNameAsString();
2057 offsetPointerIndexes[2] = llvm::ConstantInt::get(IndexTy, ivarIndex);
2058 // Get the correct ivar field
2059 llvm::Constant *offsetValue = llvm::ConstantExpr::getGetElementPtr(
2060 IvarList, offsetPointerIndexes);
2061 // Get the existing variable, if one exists.
2062 llvm::GlobalVariable *offset = TheModule.getNamedGlobal(Name);
2064 offset->setInitializer(offsetValue);
2065 // If this is the real definition, change its linkage type so that
2066 // different modules will use this one, rather than their private
2068 offset->setLinkage(llvm::GlobalValue::ExternalLinkage);
2070 // Add a new alias if there isn't one already.
2071 offset = new llvm::GlobalVariable(TheModule, offsetValue->getType(),
2072 false, llvm::GlobalValue::ExternalLinkage, offsetValue, Name);
2076 llvm::Constant *Zero64 = llvm::ConstantInt::get(Int64Ty, 0);
2077 //Generate metaclass for class methods
2078 llvm::Constant *MetaClassStruct = GenerateClassStructure(NULLPtr,
2079 NULLPtr, 0x12L, ClassName.c_str(), 0, Zeros[0], GenerateIvarList(
2080 empty, empty, empty), ClassMethodList, NULLPtr,
2081 NULLPtr, NULLPtr, Zero64, Zero64, true);
2083 // Generate the class structure
2084 llvm::Constant *ClassStruct =
2085 GenerateClassStructure(MetaClassStruct, SuperClass, 0x11L,
2086 ClassName.c_str(), 0,
2087 llvm::ConstantInt::get(LongTy, instanceSize), IvarList,
2088 MethodList, GenerateProtocolList(Protocols), IvarOffsetArray,
2089 Properties, StrongIvarBitmap, WeakIvarBitmap);
2091 // Resolve the class aliases, if they exist.
2092 if (ClassPtrAlias) {
2093 ClassPtrAlias->replaceAllUsesWith(
2094 llvm::ConstantExpr::getBitCast(ClassStruct, IdTy));
2095 ClassPtrAlias->eraseFromParent();
2098 if (MetaClassPtrAlias) {
2099 MetaClassPtrAlias->replaceAllUsesWith(
2100 llvm::ConstantExpr::getBitCast(MetaClassStruct, IdTy));
2101 MetaClassPtrAlias->eraseFromParent();
2102 MetaClassPtrAlias = 0;
2105 // Add class structure to list to be added to the symtab later
2106 ClassStruct = llvm::ConstantExpr::getBitCast(ClassStruct, PtrToInt8Ty);
2107 Classes.push_back(ClassStruct);
2111 llvm::Function *CGObjCGNU::ModuleInitFunction() {
2112 // Only emit an ObjC load function if no Objective-C stuff has been called
2113 if (Classes.empty() && Categories.empty() && ConstantStrings.empty() &&
2114 ExistingProtocols.empty() && SelectorTable.empty())
2117 // Add all referenced protocols to a category.
2118 GenerateProtocolHolderCategory();
2120 llvm::StructType *SelStructTy = dyn_cast<llvm::StructType>(
2121 SelectorTy->getElementType());
2122 llvm::Type *SelStructPtrTy = SelectorTy;
2123 if (SelStructTy == 0) {
2124 SelStructTy = llvm::StructType::get(PtrToInt8Ty, PtrToInt8Ty, NULL);
2125 SelStructPtrTy = llvm::PointerType::getUnqual(SelStructTy);
2128 std::vector<llvm::Constant*> Elements;
2129 llvm::Constant *Statics = NULLPtr;
2130 // Generate statics list:
2131 if (ConstantStrings.size()) {
2132 llvm::ArrayType *StaticsArrayTy = llvm::ArrayType::get(PtrToInt8Ty,
2133 ConstantStrings.size() + 1);
2134 ConstantStrings.push_back(NULLPtr);
2136 StringRef StringClass = CGM.getLangOptions().ObjCConstantStringClass;
2138 if (StringClass.empty()) StringClass = "NXConstantString";
2140 Elements.push_back(MakeConstantString(StringClass,
2141 ".objc_static_class_name"));
2142 Elements.push_back(llvm::ConstantArray::get(StaticsArrayTy,
2144 llvm::StructType *StaticsListTy =
2145 llvm::StructType::get(PtrToInt8Ty, StaticsArrayTy, NULL);
2146 llvm::Type *StaticsListPtrTy =
2147 llvm::PointerType::getUnqual(StaticsListTy);
2148 Statics = MakeGlobal(StaticsListTy, Elements, ".objc_statics");
2149 llvm::ArrayType *StaticsListArrayTy =
2150 llvm::ArrayType::get(StaticsListPtrTy, 2);
2152 Elements.push_back(Statics);
2153 Elements.push_back(llvm::Constant::getNullValue(StaticsListPtrTy));
2154 Statics = MakeGlobal(StaticsListArrayTy, Elements, ".objc_statics_ptr");
2155 Statics = llvm::ConstantExpr::getBitCast(Statics, PtrTy);
2157 // Array of classes, categories, and constant objects
2158 llvm::ArrayType *ClassListTy = llvm::ArrayType::get(PtrToInt8Ty,
2159 Classes.size() + Categories.size() + 2);
2160 llvm::StructType *SymTabTy = llvm::StructType::get(LongTy, SelStructPtrTy,
2161 llvm::Type::getInt16Ty(VMContext),
2162 llvm::Type::getInt16Ty(VMContext),
2166 // Pointer to an array of selectors used in this module.
2167 std::vector<llvm::Constant*> Selectors;
2168 std::vector<llvm::GlobalAlias*> SelectorAliases;
2169 for (SelectorMap::iterator iter = SelectorTable.begin(),
2170 iterEnd = SelectorTable.end(); iter != iterEnd ; ++iter) {
2172 std::string SelNameStr = iter->first.getAsString();
2173 llvm::Constant *SelName = ExportUniqueString(SelNameStr, ".objc_sel_name");
2175 SmallVectorImpl<TypedSelector> &Types = iter->second;
2176 for (SmallVectorImpl<TypedSelector>::iterator i = Types.begin(),
2177 e = Types.end() ; i!=e ; i++) {
2179 llvm::Constant *SelectorTypeEncoding = NULLPtr;
2180 if (!i->first.empty())
2181 SelectorTypeEncoding = MakeConstantString(i->first, ".objc_sel_types");
2183 Elements.push_back(SelName);
2184 Elements.push_back(SelectorTypeEncoding);
2185 Selectors.push_back(llvm::ConstantStruct::get(SelStructTy, Elements));
2188 // Store the selector alias for later replacement
2189 SelectorAliases.push_back(i->second);
2192 unsigned SelectorCount = Selectors.size();
2193 // NULL-terminate the selector list. This should not actually be required,
2194 // because the selector list has a length field. Unfortunately, the GCC
2195 // runtime decides to ignore the length field and expects a NULL terminator,
2196 // and GCC cooperates with this by always setting the length to 0.
2197 Elements.push_back(NULLPtr);
2198 Elements.push_back(NULLPtr);
2199 Selectors.push_back(llvm::ConstantStruct::get(SelStructTy, Elements));
2202 // Number of static selectors
2203 Elements.push_back(llvm::ConstantInt::get(LongTy, SelectorCount));
2204 llvm::Constant *SelectorList = MakeGlobalArray(SelStructTy, Selectors,
2205 ".objc_selector_list");
2206 Elements.push_back(llvm::ConstantExpr::getBitCast(SelectorList,
2209 // Now that all of the static selectors exist, create pointers to them.
2210 for (unsigned int i=0 ; i<SelectorCount ; i++) {
2212 llvm::Constant *Idxs[] = {Zeros[0],
2213 llvm::ConstantInt::get(Int32Ty, i), Zeros[0]};
2214 // FIXME: We're generating redundant loads and stores here!
2215 llvm::Constant *SelPtr = llvm::ConstantExpr::getGetElementPtr(SelectorList,
2216 makeArrayRef(Idxs, 2));
2217 // If selectors are defined as an opaque type, cast the pointer to this
2219 SelPtr = llvm::ConstantExpr::getBitCast(SelPtr, SelectorTy);
2220 SelectorAliases[i]->replaceAllUsesWith(SelPtr);
2221 SelectorAliases[i]->eraseFromParent();
2224 // Number of classes defined.
2225 Elements.push_back(llvm::ConstantInt::get(llvm::Type::getInt16Ty(VMContext),
2227 // Number of categories defined
2228 Elements.push_back(llvm::ConstantInt::get(llvm::Type::getInt16Ty(VMContext),
2229 Categories.size()));
2230 // Create an array of classes, then categories, then static object instances
2231 Classes.insert(Classes.end(), Categories.begin(), Categories.end());
2232 // NULL-terminated list of static object instances (mainly constant strings)
2233 Classes.push_back(Statics);
2234 Classes.push_back(NULLPtr);
2235 llvm::Constant *ClassList = llvm::ConstantArray::get(ClassListTy, Classes);
2236 Elements.push_back(ClassList);
2237 // Construct the symbol table
2238 llvm::Constant *SymTab= MakeGlobal(SymTabTy, Elements);
2240 // The symbol table is contained in a module which has some version-checking
2242 llvm::StructType * ModuleTy = llvm::StructType::get(LongTy, LongTy,
2243 PtrToInt8Ty, llvm::PointerType::getUnqual(SymTabTy),
2244 (RuntimeVersion >= 10) ? IntTy : NULL, NULL);
2246 // Runtime version, used for ABI compatibility checking.
2247 Elements.push_back(llvm::ConstantInt::get(LongTy, RuntimeVersion));
2249 llvm::TargetData td(&TheModule);
2251 llvm::ConstantInt::get(LongTy,
2252 td.getTypeSizeInBits(ModuleTy) /
2253 CGM.getContext().getCharWidth()));
2255 // The path to the source file where this module was declared
2256 SourceManager &SM = CGM.getContext().getSourceManager();
2257 const FileEntry *mainFile = SM.getFileEntryForID(SM.getMainFileID());
2259 std::string(mainFile->getDir()->getName()) + '/' + mainFile->getName();
2260 Elements.push_back(MakeConstantString(path, ".objc_source_file_name"));
2261 Elements.push_back(SymTab);
2263 if (RuntimeVersion >= 10)
2264 switch (CGM.getLangOptions().getGC()) {
2265 case LangOptions::GCOnly:
2266 Elements.push_back(llvm::ConstantInt::get(IntTy, 2));
2268 case LangOptions::NonGC:
2269 if (CGM.getLangOptions().ObjCAutoRefCount)
2270 Elements.push_back(llvm::ConstantInt::get(IntTy, 1));
2272 Elements.push_back(llvm::ConstantInt::get(IntTy, 0));
2274 case LangOptions::HybridGC:
2275 Elements.push_back(llvm::ConstantInt::get(IntTy, 1));
2279 llvm::Value *Module = MakeGlobal(ModuleTy, Elements);
2281 // Create the load function calling the runtime entry point with the module
2283 llvm::Function * LoadFunction = llvm::Function::Create(
2284 llvm::FunctionType::get(llvm::Type::getVoidTy(VMContext), false),
2285 llvm::GlobalValue::InternalLinkage, ".objc_load_function",
2287 llvm::BasicBlock *EntryBB =
2288 llvm::BasicBlock::Create(VMContext, "entry", LoadFunction);
2289 CGBuilderTy Builder(VMContext);
2290 Builder.SetInsertPoint(EntryBB);
2292 llvm::FunctionType *FT =
2293 llvm::FunctionType::get(Builder.getVoidTy(),
2294 llvm::PointerType::getUnqual(ModuleTy), true);
2295 llvm::Value *Register = CGM.CreateRuntimeFunction(FT, "__objc_exec_class");
2296 Builder.CreateCall(Register, Module);
2297 Builder.CreateRetVoid();
2299 return LoadFunction;
2302 llvm::Function *CGObjCGNU::GenerateMethod(const ObjCMethodDecl *OMD,
2303 const ObjCContainerDecl *CD) {
2304 const ObjCCategoryImplDecl *OCD =
2305 dyn_cast<ObjCCategoryImplDecl>(OMD->getDeclContext());
2306 StringRef CategoryName = OCD ? OCD->getName() : "";
2307 StringRef ClassName = CD->getName();
2308 Selector MethodName = OMD->getSelector();
2309 bool isClassMethod = !OMD->isInstanceMethod();
2311 CodeGenTypes &Types = CGM.getTypes();
2312 llvm::FunctionType *MethodTy =
2313 Types.GetFunctionType(Types.getFunctionInfo(OMD), OMD->isVariadic());
2314 std::string FunctionName = SymbolNameForMethod(ClassName, CategoryName,
2315 MethodName, isClassMethod);
2317 llvm::Function *Method
2318 = llvm::Function::Create(MethodTy,
2319 llvm::GlobalValue::InternalLinkage,
2325 llvm::Constant *CGObjCGNU::GetPropertyGetFunction() {
2326 return GetPropertyFn;
2329 llvm::Constant *CGObjCGNU::GetPropertySetFunction() {
2330 return SetPropertyFn;
2333 llvm::Constant *CGObjCGNU::GetGetStructFunction() {
2334 return GetStructPropertyFn;
2336 llvm::Constant *CGObjCGNU::GetSetStructFunction() {
2337 return SetStructPropertyFn;
2340 llvm::Constant *CGObjCGNU::EnumerationMutationFunction() {
2341 return EnumerationMutationFn;
2344 void CGObjCGNU::EmitSynchronizedStmt(CodeGenFunction &CGF,
2345 const ObjCAtSynchronizedStmt &S) {
2346 EmitAtSynchronizedStmt(CGF, S, SyncEnterFn, SyncExitFn);
2350 void CGObjCGNU::EmitTryStmt(CodeGenFunction &CGF,
2351 const ObjCAtTryStmt &S) {
2352 // Unlike the Apple non-fragile runtimes, which also uses
2353 // unwind-based zero cost exceptions, the GNU Objective C runtime's
2354 // EH support isn't a veneer over C++ EH. Instead, exception
2355 // objects are created by __objc_exception_throw and destroyed by
2356 // the personality function; this avoids the need for bracketing
2357 // catch handlers with calls to __blah_begin_catch/__blah_end_catch
2358 // (or even _Unwind_DeleteException), but probably doesn't
2359 // interoperate very well with foreign exceptions.
2361 // In Objective-C++ mode, we actually emit something equivalent to the C++
2362 // exception handler.
2363 EmitTryCatchStmt(CGF, S, EnterCatchFn, ExitCatchFn, ExceptionReThrowFn);
2367 void CGObjCGNU::EmitThrowStmt(CodeGenFunction &CGF,
2368 const ObjCAtThrowStmt &S) {
2369 llvm::Value *ExceptionAsObject;
2371 if (const Expr *ThrowExpr = S.getThrowExpr()) {
2372 llvm::Value *Exception = CGF.EmitObjCThrowOperand(ThrowExpr);
2373 ExceptionAsObject = Exception;
2375 assert((!CGF.ObjCEHValueStack.empty() && CGF.ObjCEHValueStack.back()) &&
2376 "Unexpected rethrow outside @catch block.");
2377 ExceptionAsObject = CGF.ObjCEHValueStack.back();
2379 ExceptionAsObject = CGF.Builder.CreateBitCast(ExceptionAsObject, IdTy);
2381 // Note: This may have to be an invoke, if we want to support constructs like:
2387 // This is effectively turning @throw into an incredibly-expensive goto, but
2388 // it may happen as a result of inlining followed by missed optimizations, or
2389 // as a result of stupidity.
2390 llvm::BasicBlock *UnwindBB = CGF.getInvokeDest();
2392 CGF.Builder.CreateCall(ExceptionThrowFn, ExceptionAsObject);
2393 CGF.Builder.CreateUnreachable();
2395 CGF.Builder.CreateInvoke(ExceptionThrowFn, UnwindBB, UnwindBB,
2398 // Clear the insertion point to indicate we are in unreachable code.
2399 CGF.Builder.ClearInsertionPoint();
2402 llvm::Value * CGObjCGNU::EmitObjCWeakRead(CodeGenFunction &CGF,
2403 llvm::Value *AddrWeakObj) {
2404 CGBuilderTy B = CGF.Builder;
2405 AddrWeakObj = EnforceType(B, AddrWeakObj, PtrToIdTy);
2406 return B.CreateCall(WeakReadFn, AddrWeakObj);
2409 void CGObjCGNU::EmitObjCWeakAssign(CodeGenFunction &CGF,
2410 llvm::Value *src, llvm::Value *dst) {
2411 CGBuilderTy B = CGF.Builder;
2412 src = EnforceType(B, src, IdTy);
2413 dst = EnforceType(B, dst, PtrToIdTy);
2414 B.CreateCall2(WeakAssignFn, src, dst);
2417 void CGObjCGNU::EmitObjCGlobalAssign(CodeGenFunction &CGF,
2418 llvm::Value *src, llvm::Value *dst,
2420 CGBuilderTy B = CGF.Builder;
2421 src = EnforceType(B, src, IdTy);
2422 dst = EnforceType(B, dst, PtrToIdTy);
2424 B.CreateCall2(GlobalAssignFn, src, dst);
2426 // FIXME. Add threadloca assign API
2427 llvm_unreachable("EmitObjCGlobalAssign - Threal Local API NYI");
2430 void CGObjCGNU::EmitObjCIvarAssign(CodeGenFunction &CGF,
2431 llvm::Value *src, llvm::Value *dst,
2432 llvm::Value *ivarOffset) {
2433 CGBuilderTy B = CGF.Builder;
2434 src = EnforceType(B, src, IdTy);
2435 dst = EnforceType(B, dst, IdTy);
2436 B.CreateCall3(IvarAssignFn, src, dst, ivarOffset);
2439 void CGObjCGNU::EmitObjCStrongCastAssign(CodeGenFunction &CGF,
2440 llvm::Value *src, llvm::Value *dst) {
2441 CGBuilderTy B = CGF.Builder;
2442 src = EnforceType(B, src, IdTy);
2443 dst = EnforceType(B, dst, PtrToIdTy);
2444 B.CreateCall2(StrongCastAssignFn, src, dst);
2447 void CGObjCGNU::EmitGCMemmoveCollectable(CodeGenFunction &CGF,
2448 llvm::Value *DestPtr,
2449 llvm::Value *SrcPtr,
2450 llvm::Value *Size) {
2451 CGBuilderTy B = CGF.Builder;
2452 DestPtr = EnforceType(B, DestPtr, PtrTy);
2453 SrcPtr = EnforceType(B, SrcPtr, PtrTy);
2455 B.CreateCall3(MemMoveFn, DestPtr, SrcPtr, Size);
2458 llvm::GlobalVariable *CGObjCGNU::ObjCIvarOffsetVariable(
2459 const ObjCInterfaceDecl *ID,
2460 const ObjCIvarDecl *Ivar) {
2461 const std::string Name = "__objc_ivar_offset_" + ID->getNameAsString()
2462 + '.' + Ivar->getNameAsString();
2463 // Emit the variable and initialize it with what we think the correct value
2464 // is. This allows code compiled with non-fragile ivars to work correctly
2465 // when linked against code which isn't (most of the time).
2466 llvm::GlobalVariable *IvarOffsetPointer = TheModule.getNamedGlobal(Name);
2467 if (!IvarOffsetPointer) {
2468 // This will cause a run-time crash if we accidentally use it. A value of
2469 // 0 would seem more sensible, but will silently overwrite the isa pointer
2470 // causing a great deal of confusion.
2471 uint64_t Offset = -1;
2472 // We can't call ComputeIvarBaseOffset() here if we have the
2473 // implementation, because it will create an invalid ASTRecordLayout object
2474 // that we are then stuck with forever, so we only initialize the ivar
2475 // offset variable with a guess if we only have the interface. The
2476 // initializer will be reset later anyway, when we are generating the class
2478 if (!CGM.getContext().getObjCImplementation(
2479 const_cast<ObjCInterfaceDecl *>(ID)))
2480 Offset = ComputeIvarBaseOffset(CGM, ID, Ivar);
2482 llvm::ConstantInt *OffsetGuess = llvm::ConstantInt::get(Int32Ty, Offset,
2484 // Don't emit the guess in non-PIC code because the linker will not be able
2485 // to replace it with the real version for a library. In non-PIC code you
2486 // must compile with the fragile ABI if you want to use ivars from a
2487 // GCC-compiled class.
2488 if (CGM.getLangOptions().PICLevel) {
2489 llvm::GlobalVariable *IvarOffsetGV = new llvm::GlobalVariable(TheModule,
2491 llvm::GlobalValue::PrivateLinkage, OffsetGuess, Name+".guess");
2492 IvarOffsetPointer = new llvm::GlobalVariable(TheModule,
2493 IvarOffsetGV->getType(), false, llvm::GlobalValue::LinkOnceAnyLinkage,
2494 IvarOffsetGV, Name);
2496 IvarOffsetPointer = new llvm::GlobalVariable(TheModule,
2497 llvm::Type::getInt32PtrTy(VMContext), false,
2498 llvm::GlobalValue::ExternalLinkage, 0, Name);
2501 return IvarOffsetPointer;
2504 LValue CGObjCGNU::EmitObjCValueForIvar(CodeGenFunction &CGF,
2506 llvm::Value *BaseValue,
2507 const ObjCIvarDecl *Ivar,
2508 unsigned CVRQualifiers) {
2509 const ObjCInterfaceDecl *ID =
2510 ObjectTy->getAs<ObjCObjectType>()->getInterface();
2511 return EmitValueForIvarAtOffset(CGF, ID, BaseValue, Ivar, CVRQualifiers,
2512 EmitIvarOffset(CGF, ID, Ivar));
2515 static const ObjCInterfaceDecl *FindIvarInterface(ASTContext &Context,
2516 const ObjCInterfaceDecl *OID,
2517 const ObjCIvarDecl *OIVD) {
2518 for (const ObjCIvarDecl *next = OID->all_declared_ivar_begin(); next;
2519 next = next->getNextIvar()) {
2524 // Otherwise check in the super class.
2525 if (const ObjCInterfaceDecl *Super = OID->getSuperClass())
2526 return FindIvarInterface(Context, Super, OIVD);
2531 llvm::Value *CGObjCGNU::EmitIvarOffset(CodeGenFunction &CGF,
2532 const ObjCInterfaceDecl *Interface,
2533 const ObjCIvarDecl *Ivar) {
2534 if (CGM.getLangOptions().ObjCNonFragileABI) {
2535 Interface = FindIvarInterface(CGM.getContext(), Interface, Ivar);
2536 if (RuntimeVersion < 10)
2537 return CGF.Builder.CreateZExtOrBitCast(
2538 CGF.Builder.CreateLoad(CGF.Builder.CreateLoad(
2539 ObjCIvarOffsetVariable(Interface, Ivar), false, "ivar")),
2541 std::string name = "__objc_ivar_offset_value_" +
2542 Interface->getNameAsString() +"." + Ivar->getNameAsString();
2543 llvm::Value *Offset = TheModule.getGlobalVariable(name);
2545 Offset = new llvm::GlobalVariable(TheModule, IntTy,
2546 false, llvm::GlobalValue::LinkOnceAnyLinkage,
2547 llvm::Constant::getNullValue(IntTy), name);
2548 return CGF.Builder.CreateLoad(Offset);
2550 uint64_t Offset = ComputeIvarBaseOffset(CGF.CGM, Interface, Ivar);
2551 return llvm::ConstantInt::get(PtrDiffTy, Offset, /*isSigned*/true);
2555 clang::CodeGen::CreateGNUObjCRuntime(CodeGenModule &CGM) {
2556 if (CGM.getLangOptions().ObjCNonFragileABI)
2557 return new CGObjCGNUstep(CGM);
2558 return new CGObjCGCC(CGM);