1 //===----- CGObjCRuntime.h - Interface to ObjC Runtimes ---------*- C++ -*-===//
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 an abstract class for Objective-C code generation. Concrete
11 // subclasses of this implement code generation for specific Objective-C
14 //===----------------------------------------------------------------------===//
16 #ifndef LLVM_CLANG_LIB_CODEGEN_CGOBJCRUNTIME_H
17 #define LLVM_CLANG_LIB_CODEGEN_CGOBJCRUNTIME_H
18 #include "CGBuilder.h"
21 #include "clang/AST/DeclObjC.h"
22 #include "clang/Basic/IdentifierTable.h" // Selector
36 class CodeGenFunction;
41 class ObjCAtThrowStmt;
42 class ObjCAtSynchronizedStmt;
43 class ObjCContainerDecl;
44 class ObjCCategoryImplDecl;
45 class ObjCImplementationDecl;
46 class ObjCInterfaceDecl;
47 class ObjCMessageExpr;
49 class ObjCProtocolDecl;
52 class ObjCStringLiteral;
53 class BlockDeclRefExpr;
59 // FIXME: Several methods should be pure virtual but aren't to avoid the
60 // partially-implemented subclass breaking.
62 /// Implements runtime-specific code generation functions.
65 CodeGen::CodeGenModule &CGM;
66 CGObjCRuntime(CodeGen::CodeGenModule &CGM) : CGM(CGM) {}
68 // Utility functions for unified ivar access. These need to
69 // eventually be folded into other places (the structure layout
72 /// Compute an offset to the given ivar, suitable for passing to
73 /// EmitValueForIvarAtOffset. Note that the correct handling of
74 /// bit-fields is carefully coordinated by these two, use caution!
76 /// The latter overload is suitable for computing the offset of a
78 uint64_t ComputeIvarBaseOffset(CodeGen::CodeGenModule &CGM,
79 const ObjCInterfaceDecl *OID,
80 const ObjCIvarDecl *Ivar);
81 uint64_t ComputeIvarBaseOffset(CodeGen::CodeGenModule &CGM,
82 const ObjCImplementationDecl *OID,
83 const ObjCIvarDecl *Ivar);
85 LValue EmitValueForIvarAtOffset(CodeGen::CodeGenFunction &CGF,
86 const ObjCInterfaceDecl *OID,
87 llvm::Value *BaseValue,
88 const ObjCIvarDecl *Ivar,
89 unsigned CVRQualifiers,
91 /// Emits a try / catch statement. This function is intended to be called by
92 /// subclasses, and provides a generic mechanism for generating these, which
93 /// should be usable by all runtimes. The caller must provide the functions
94 /// to call when entering and exiting a \@catch() block, and the function
95 /// used to rethrow exceptions. If the begin and end catch functions are
96 /// NULL, then the function assumes that the EH personality function provides
97 /// the thrown object directly.
98 void EmitTryCatchStmt(CodeGenFunction &CGF,
99 const ObjCAtTryStmt &S,
100 llvm::Constant *beginCatchFn,
101 llvm::Constant *endCatchFn,
102 llvm::Constant *exceptionRethrowFn);
104 void EmitInitOfCatchParam(CodeGenFunction &CGF, llvm::Value *exn,
105 const VarDecl *paramDecl);
107 /// Emits an \@synchronize() statement, using the \p syncEnterFn and
108 /// \p syncExitFn arguments as the functions called to lock and unlock
109 /// the object. This function can be called by subclasses that use
110 /// zero-cost exception handling.
111 void EmitAtSynchronizedStmt(CodeGenFunction &CGF,
112 const ObjCAtSynchronizedStmt &S,
113 llvm::Function *syncEnterFn,
114 llvm::Function *syncExitFn);
117 virtual ~CGObjCRuntime();
119 /// Generate the function required to register all Objective-C components in
120 /// this compilation unit with the runtime library.
121 virtual llvm::Function *ModuleInitFunction() = 0;
123 /// Get a selector for the specified name and type values.
124 /// The result should have the LLVM type for ASTContext::getObjCSelType().
125 virtual llvm::Value *GetSelector(CodeGenFunction &CGF, Selector Sel) = 0;
127 /// Get the address of a selector for the specified name and type values.
128 /// This is a rarely-used language extension, but sadly it exists.
130 /// The result should have the LLVM type for a pointer to
131 /// ASTContext::getObjCSelType().
132 virtual Address GetAddrOfSelector(CodeGenFunction &CGF, Selector Sel) = 0;
134 /// Get a typed selector.
135 virtual llvm::Value *GetSelector(CodeGenFunction &CGF,
136 const ObjCMethodDecl *Method) = 0;
138 /// Get the type constant to catch for the given ObjC pointer type.
139 /// This is used externally to implement catching ObjC types in C++.
140 /// Runtimes which don't support this should add the appropriate
142 virtual llvm::Constant *GetEHType(QualType T) = 0;
144 /// Generate a constant string object.
145 virtual ConstantAddress GenerateConstantString(const StringLiteral *) = 0;
147 /// Generate a category. A category contains a list of methods (and
148 /// accompanying metadata) and a list of protocols.
149 virtual void GenerateCategory(const ObjCCategoryImplDecl *OCD) = 0;
151 /// Generate a class structure for this class.
152 virtual void GenerateClass(const ObjCImplementationDecl *OID) = 0;
154 /// Register an class alias.
155 virtual void RegisterAlias(const ObjCCompatibleAliasDecl *OAD) = 0;
157 /// Generate an Objective-C message send operation.
159 /// \param Method - The method being called, this may be null if synthesizing
160 /// a property setter or getter.
161 virtual CodeGen::RValue
162 GenerateMessageSend(CodeGen::CodeGenFunction &CGF,
163 ReturnValueSlot ReturnSlot,
166 llvm::Value *Receiver,
167 const CallArgList &CallArgs,
168 const ObjCInterfaceDecl *Class = nullptr,
169 const ObjCMethodDecl *Method = nullptr) = 0;
171 /// Generate an Objective-C message send operation to the super
172 /// class initiated in a method for Class and with the given Self
175 /// \param Method - The method being called, this may be null if synthesizing
176 /// a property setter or getter.
177 virtual CodeGen::RValue
178 GenerateMessageSendSuper(CodeGen::CodeGenFunction &CGF,
179 ReturnValueSlot ReturnSlot,
182 const ObjCInterfaceDecl *Class,
186 const CallArgList &CallArgs,
187 const ObjCMethodDecl *Method = nullptr) = 0;
189 /// Emit the code to return the named protocol as an object, as in a
190 /// \@protocol expression.
191 virtual llvm::Value *GenerateProtocolRef(CodeGenFunction &CGF,
192 const ObjCProtocolDecl *OPD) = 0;
194 /// Generate the named protocol. Protocols contain method metadata but no
196 virtual void GenerateProtocol(const ObjCProtocolDecl *OPD) = 0;
198 /// Generate a function preamble for a method with the specified
201 // FIXME: Current this just generates the Function definition, but really this
202 // should also be generating the loads of the parameters, as the runtime
203 // should have full control over how parameters are passed.
204 virtual llvm::Function *GenerateMethod(const ObjCMethodDecl *OMD,
205 const ObjCContainerDecl *CD) = 0;
207 /// Return the runtime function for getting properties.
208 virtual llvm::Constant *GetPropertyGetFunction() = 0;
210 /// Return the runtime function for setting properties.
211 virtual llvm::Constant *GetPropertySetFunction() = 0;
213 /// Return the runtime function for optimized setting properties.
214 virtual llvm::Constant *GetOptimizedPropertySetFunction(bool atomic,
217 // API for atomic copying of qualified aggregates in getter.
218 virtual llvm::Constant *GetGetStructFunction() = 0;
219 // API for atomic copying of qualified aggregates in setter.
220 virtual llvm::Constant *GetSetStructFunction() = 0;
221 /// API for atomic copying of qualified aggregates with non-trivial copy
222 /// assignment (c++) in setter.
223 virtual llvm::Constant *GetCppAtomicObjectSetFunction() = 0;
224 /// API for atomic copying of qualified aggregates with non-trivial copy
225 /// assignment (c++) in getter.
226 virtual llvm::Constant *GetCppAtomicObjectGetFunction() = 0;
228 /// GetClass - Return a reference to the class for the given
230 virtual llvm::Value *GetClass(CodeGenFunction &CGF,
231 const ObjCInterfaceDecl *OID) = 0;
234 virtual llvm::Value *EmitNSAutoreleasePoolClassRef(CodeGenFunction &CGF) {
235 llvm_unreachable("autoreleasepool unsupported in this ABI");
238 /// EnumerationMutationFunction - Return the function that's called by the
239 /// compiler when a mutation is detected during foreach iteration.
240 virtual llvm::Constant *EnumerationMutationFunction() = 0;
242 virtual void EmitSynchronizedStmt(CodeGen::CodeGenFunction &CGF,
243 const ObjCAtSynchronizedStmt &S) = 0;
244 virtual void EmitTryStmt(CodeGen::CodeGenFunction &CGF,
245 const ObjCAtTryStmt &S) = 0;
246 virtual void EmitThrowStmt(CodeGen::CodeGenFunction &CGF,
247 const ObjCAtThrowStmt &S,
248 bool ClearInsertionPoint=true) = 0;
249 virtual llvm::Value *EmitObjCWeakRead(CodeGen::CodeGenFunction &CGF,
250 Address AddrWeakObj) = 0;
251 virtual void EmitObjCWeakAssign(CodeGen::CodeGenFunction &CGF,
252 llvm::Value *src, Address dest) = 0;
253 virtual void EmitObjCGlobalAssign(CodeGen::CodeGenFunction &CGF,
254 llvm::Value *src, Address dest,
255 bool threadlocal=false) = 0;
256 virtual void EmitObjCIvarAssign(CodeGen::CodeGenFunction &CGF,
257 llvm::Value *src, Address dest,
258 llvm::Value *ivarOffset) = 0;
259 virtual void EmitObjCStrongCastAssign(CodeGen::CodeGenFunction &CGF,
260 llvm::Value *src, Address dest) = 0;
262 virtual LValue EmitObjCValueForIvar(CodeGen::CodeGenFunction &CGF,
264 llvm::Value *BaseValue,
265 const ObjCIvarDecl *Ivar,
266 unsigned CVRQualifiers) = 0;
267 virtual llvm::Value *EmitIvarOffset(CodeGen::CodeGenFunction &CGF,
268 const ObjCInterfaceDecl *Interface,
269 const ObjCIvarDecl *Ivar) = 0;
270 virtual void EmitGCMemmoveCollectable(CodeGen::CodeGenFunction &CGF,
273 llvm::Value *Size) = 0;
274 virtual llvm::Constant *BuildGCBlockLayout(CodeGen::CodeGenModule &CGM,
275 const CodeGen::CGBlockInfo &blockInfo) = 0;
276 virtual llvm::Constant *BuildRCBlockLayout(CodeGen::CodeGenModule &CGM,
277 const CodeGen::CGBlockInfo &blockInfo) = 0;
279 /// Returns an i8* which points to the byref layout information.
280 virtual llvm::Constant *BuildByrefLayout(CodeGen::CodeGenModule &CGM,
283 struct MessageSendInfo {
284 const CGFunctionInfo &CallInfo;
285 llvm::PointerType *MessengerType;
287 MessageSendInfo(const CGFunctionInfo &callInfo,
288 llvm::PointerType *messengerType)
289 : CallInfo(callInfo), MessengerType(messengerType) {}
292 MessageSendInfo getMessageSendInfo(const ObjCMethodDecl *method,
294 CallArgList &callArgs);
296 // FIXME: This probably shouldn't be here, but the code to compute
298 unsigned ComputeBitfieldBitOffset(CodeGen::CodeGenModule &CGM,
299 const ObjCInterfaceDecl *ID,
300 const ObjCIvarDecl *Ivar);
303 /// Creates an instance of an Objective-C runtime class.
304 //TODO: This should include some way of selecting which runtime to target.
305 CGObjCRuntime *CreateGNUObjCRuntime(CodeGenModule &CGM);
306 CGObjCRuntime *CreateMacObjCRuntime(CodeGenModule &CGM);