lib/CodeGen/CGObjCRuntime.h

   1 //===----- CGObjCRuntime.h - Interface to ObjC Runtimes ---------*- C++ -*-===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9 //
  10 // This provides an abstract class for Objective-C code generation.  Concrete
  11 // subclasses of this implement code generation for specific Objective-C
  12 // runtime libraries.
  13 //
  14 //===----------------------------------------------------------------------===//
  15
  16 #ifndef CLANG_CODEGEN_OBCJRUNTIME_H
  17 #define CLANG_CODEGEN_OBCJRUNTIME_H
  18 #include "clang/Basic/IdentifierTable.h" // Selector
  19 #include "clang/AST/DeclObjC.h"
  20 #include <string>
  21
  22 #include "CGBuilder.h"
  23 #include "CGCall.h"
  24 #include "CGValue.h"
  25
  26 namespace llvm {
  27   class Constant;
  28   class Function;
  29   class Module;
  30   class StructLayout;
  31   class StructType;
  32   class Type;
  33   class Value;
  34 }
  35
  36 namespace clang {
  37 namespace CodeGen {
  38   class CodeGenFunction;
  39 }
  40
  41   class FieldDecl;
  42   class ObjCAtTryStmt;
  43   class ObjCAtThrowStmt;
  44   class ObjCAtSynchronizedStmt;
  45   class ObjCContainerDecl;
  46   class ObjCCategoryImplDecl;
  47   class ObjCImplementationDecl;
  48   class ObjCInterfaceDecl;
  49   class ObjCMessageExpr;
  50   class ObjCMethodDecl;
  51   class ObjCProtocolDecl;
  52   class Selector;
  53   class ObjCIvarDecl;
  54   class ObjCStringLiteral;
  55   class BlockDeclRefExpr;
  56
  57 namespace CodeGen {
  58   class CodeGenModule;
  59   class CGBlockInfo;
  60
  61 // FIXME: Several methods should be pure virtual but aren't to avoid the
  62 // partially-implemented subclass breaking.
  63
  64 /// Implements runtime-specific code generation functions.
  65 class CGObjCRuntime {
  66 protected:
  67   // Utility functions for unified ivar access. These need to
  68   // eventually be folded into other places (the structure layout
  69   // code).
  70
  71   /// Compute an offset to the given ivar, suitable for passing to
  72   /// EmitValueForIvarAtOffset.  Note that the correct handling of
  73   /// bit-fields is carefully coordinated by these two, use caution!
  74   ///
  75   /// The latter overload is suitable for computing the offset of a
  76   /// sythesized ivar.
  77   uint64_t ComputeIvarBaseOffset(CodeGen::CodeGenModule &CGM,
  78                                  const ObjCInterfaceDecl *OID,
  79                                  const ObjCIvarDecl *Ivar);
  80   uint64_t ComputeIvarBaseOffset(CodeGen::CodeGenModule &CGM,
  81                                  const ObjCImplementationDecl *OID,
  82                                  const ObjCIvarDecl *Ivar);
  83
  84   LValue EmitValueForIvarAtOffset(CodeGen::CodeGenFunction &CGF,
  85                                   const ObjCInterfaceDecl *OID,
  86                                   llvm::Value *BaseValue,
  87                                   const ObjCIvarDecl *Ivar,
  88                                   unsigned CVRQualifiers,
  89                                   llvm::Value *Offset);
  90
  91 public:
  92   virtual ~CGObjCRuntime();
  93
  94   /// Generate the function required to register all Objective-C components in
  95   /// this compilation unit with the runtime library.
  96   virtual llvm::Function *ModuleInitFunction() = 0;
  97
  98   /// Get a selector for the specified name and type values. The
  99   /// return value should have the LLVM type for pointer-to
 100   /// ASTContext::getObjCSelType().
 101   virtual llvm::Value *GetSelector(CGBuilderTy &Builder,
 102                                    Selector Sel, bool lval=false) = 0;
 103
 104   /// Get a typed selector.
 105   virtual llvm::Value *GetSelector(CGBuilderTy &Builder,
 106                                    const ObjCMethodDecl *Method) = 0;
 107
 108   /// Get the type constant to catch for the given ObjC pointer type.
 109   /// This is used externally to implement catching ObjC types in C++.
 110   /// Runtimes which don't support this should add the appropriate
 111   /// error to Sema.
 112   virtual llvm::Constant *GetEHType(QualType T) = 0;
 113
 114   /// Generate a constant string object.
 115   virtual llvm::Constant *GenerateConstantString(const StringLiteral *) = 0;
 116
 117   /// Generate a category.  A category contains a list of methods (and
 118   /// accompanying metadata) and a list of protocols.
 119   virtual void GenerateCategory(const ObjCCategoryImplDecl *OCD) = 0;
 120
 121   /// Generate a class stucture for this class.
 122   virtual void GenerateClass(const ObjCImplementationDecl *OID) = 0;
 123
 124   /// Generate an Objective-C message send operation.
 125   ///
 126   /// \param Method - The method being called, this may be null if synthesizing
 127   /// a property setter or getter.
 128   virtual CodeGen::RValue
 129   GenerateMessageSend(CodeGen::CodeGenFunction &CGF,
 130                       ReturnValueSlot ReturnSlot,
 131                       QualType ResultType,
 132                       Selector Sel,
 133                       llvm::Value *Receiver,
 134                       const CallArgList &CallArgs,
 135                       const ObjCInterfaceDecl *Class = 0,
 136                       const ObjCMethodDecl *Method = 0) = 0;
 137
 138   /// Generate an Objective-C message send operation to the super
 139   /// class initiated in a method for Class and with the given Self
 140   /// object.
 141   ///
 142   /// \param Method - The method being called, this may be null if synthesizing
 143   /// a property setter or getter.
 144   virtual CodeGen::RValue
 145   GenerateMessageSendSuper(CodeGen::CodeGenFunction &CGF,
 146                            ReturnValueSlot ReturnSlot,
 147                            QualType ResultType,
 148                            Selector Sel,
 149                            const ObjCInterfaceDecl *Class,
 150                            bool isCategoryImpl,
 151                            llvm::Value *Self,
 152                            bool IsClassMessage,
 153                            const CallArgList &CallArgs,
 154                            const ObjCMethodDecl *Method = 0) = 0;
 155
 156   /// Emit the code to return the named protocol as an object, as in a
 157   /// @protocol expression.
 158   virtual llvm::Value *GenerateProtocolRef(CGBuilderTy &Builder,
 159                                            const ObjCProtocolDecl *OPD) = 0;
 160
 161   /// Generate the named protocol.  Protocols contain method metadata but no
 162   /// implementations.
 163   virtual void GenerateProtocol(const ObjCProtocolDecl *OPD) = 0;
 164
 165   /// Generate a function preamble for a method with the specified
 166   /// types.
 167
 168   // FIXME: Current this just generates the Function definition, but really this
 169   // should also be generating the loads of the parameters, as the runtime
 170   // should have full control over how parameters are passed.
 171   virtual llvm::Function *GenerateMethod(const ObjCMethodDecl *OMD,
 172                                          const ObjCContainerDecl *CD) = 0;
 173
 174   /// Return the runtime function for getting properties.
 175   virtual llvm::Constant *GetPropertyGetFunction() = 0;
 176
 177   /// Return the runtime function for setting properties.
 178   virtual llvm::Constant *GetPropertySetFunction() = 0;
 179
 180   // API for atomic copying of qualified aggregates in getter.
 181   virtual llvm::Constant *GetGetStructFunction() = 0;
 182   // API for atomic copying of qualified aggregates in setter.
 183   virtual llvm::Constant *GetSetStructFunction() = 0;
 184
 185   /// GetClass - Return a reference to the class for the given
 186   /// interface decl.
 187   virtual llvm::Value *GetClass(CGBuilderTy &Builder,
 188                                 const ObjCInterfaceDecl *OID) = 0;
 189
 190   /// EnumerationMutationFunction - Return the function that's called by the
 191   /// compiler when a mutation is detected during foreach iteration.
 192   virtual llvm::Constant *EnumerationMutationFunction() = 0;
 193
 194   virtual void EmitSynchronizedStmt(CodeGen::CodeGenFunction &CGF,
 195                                     const ObjCAtSynchronizedStmt &S) = 0;
 196   virtual void EmitTryStmt(CodeGen::CodeGenFunction &CGF,
 197                            const ObjCAtTryStmt &S) = 0;
 198   virtual void EmitThrowStmt(CodeGen::CodeGenFunction &CGF,
 199                              const ObjCAtThrowStmt &S) = 0;
 200   virtual llvm::Value *EmitObjCWeakRead(CodeGen::CodeGenFunction &CGF,
 201                                         llvm::Value *AddrWeakObj) = 0;
 202   virtual void EmitObjCWeakAssign(CodeGen::CodeGenFunction &CGF,
 203                                   llvm::Value *src, llvm::Value *dest) = 0;
 204   virtual void EmitObjCGlobalAssign(CodeGen::CodeGenFunction &CGF,
 205                                     llvm::Value *src, llvm::Value *dest,
 206                                     bool threadlocal=false) = 0;
 207   virtual void EmitObjCIvarAssign(CodeGen::CodeGenFunction &CGF,
 208                                   llvm::Value *src, llvm::Value *dest,
 209                                   llvm::Value *ivarOffset) = 0;
 210   virtual void EmitObjCStrongCastAssign(CodeGen::CodeGenFunction &CGF,
 211                                         llvm::Value *src, llvm::Value *dest) = 0;
 212
 213   virtual LValue EmitObjCValueForIvar(CodeGen::CodeGenFunction &CGF,
 214                                       QualType ObjectTy,
 215                                       llvm::Value *BaseValue,
 216                                       const ObjCIvarDecl *Ivar,
 217                                       unsigned CVRQualifiers) = 0;
 218   virtual llvm::Value *EmitIvarOffset(CodeGen::CodeGenFunction &CGF,
 219                                       const ObjCInterfaceDecl *Interface,
 220                                       const ObjCIvarDecl *Ivar) = 0;
 221   virtual void EmitGCMemmoveCollectable(CodeGen::CodeGenFunction &CGF,
 222                                         llvm::Value *DestPtr,
 223                                         llvm::Value *SrcPtr,
 224                                         llvm::Value *Size) = 0;
 225   virtual llvm::Constant *BuildGCBlockLayout(CodeGen::CodeGenModule &CGM,
 226                                   const CodeGen::CGBlockInfo &blockInfo) = 0;
 227 };
 228
 229 /// Creates an instance of an Objective-C runtime class.
 230 //TODO: This should include some way of selecting which runtime to target.
 231 CGObjCRuntime *CreateGNUObjCRuntime(CodeGenModule &CGM);
 232 CGObjCRuntime *CreateMacObjCRuntime(CodeGenModule &CGM);
 233 CGObjCRuntime *CreateMacNonFragileABIObjCRuntime(CodeGenModule &CGM);
 234 }
 235 }
 236 #endif