CGObjCRuntime.h revision 2bebbf0acee55404de4b8846713b64429e744e8f 
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 "llvm/ADT/SmallVector.h"
20#include <string>
21
22#include "CGBuilder.h"
23#include "CGCall.h"
24#include "CGValue.h"
25
26namespace llvm {
27  class Constant;
28  class Function;
29  class Module;
30  class StructLayout;
31  class StructType;
32  class Type;
33  class Value;
34}
35
36namespace clang {
37namespace 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
56namespace CodeGen {
57  class CodeGenModule;
58
59//FIXME Several methods should be pure virtual but aren't to avoid the
60//partially-implemented subclass breaking.
61
62/// Implements runtime-specific code generation functions.
63class CGObjCRuntime {
64public:
65  // Utility functions for unified ivar access. These need to
66  // eventually be folded into other places (the structure layout
67  // code).
68
69protected:
70  /// Compute an offset to the given ivar, suitable for passing to
71  /// EmitValueForIvarAtOffset.  Note that the correct handling of
72  /// bit-fields is carefully coordinated by these two, use caution!
73  uint64_t ComputeIvarBaseOffset(CodeGen::CodeGenModule &CGM,
74                                 const ObjCInterfaceDecl *OID,
75                                 const ObjCIvarDecl *Ivar);
76
77  LValue EmitValueForIvarAtOffset(CodeGen::CodeGenFunction &CGF,
78                                  const ObjCInterfaceDecl *OID,
79                                  llvm::Value *BaseValue,
80                                  const ObjCIvarDecl *Ivar,
81                                  unsigned CVRQualifiers,
82                                  llvm::Value *Offset);
83
84public:
85  virtual ~CGObjCRuntime();
86
87  /// Generate the function required to register all Objective-C components in
88  /// this compilation unit with the runtime library.
89  virtual llvm::Function *ModuleInitFunction() = 0;
90
91  /// Get a selector for the specified name and type values. The
92  /// return value should have the LLVM type for pointer-to
93  /// ASTContext::getObjCSelType().
94  virtual llvm::Value *GetSelector(CGBuilderTy &Builder,
95                                   Selector Sel) = 0;
96
97  /// Generate a constant string object.
98  virtual llvm::Constant *GenerateConstantString(const ObjCStringLiteral *) = 0;
99
100  /// Generate a category.  A category contains a list of methods (and
101  /// accompanying metadata) and a list of protocols.
102  virtual void GenerateCategory(const ObjCCategoryImplDecl *OCD) = 0;
103
104  /// Generate a class stucture for this class.
105  virtual void GenerateClass(const ObjCImplementationDecl *OID) = 0;
106
107  /// Generate an Objective-C message send operation.
108  virtual CodeGen::RValue
109  GenerateMessageSend(CodeGen::CodeGenFunction &CGF,
110                      QualType ResultType,
111                      Selector Sel,
112                      llvm::Value *Receiver,
113                      bool IsClassMessage,
114                      const CallArgList &CallArgs) = 0;
115
116  /// Generate an Objective-C message send operation to the super
117  /// class initiated in a method for Class and with the given Self
118  /// object.
119  virtual CodeGen::RValue
120  GenerateMessageSendSuper(CodeGen::CodeGenFunction &CGF,
121                           QualType ResultType,
122                           Selector Sel,
123                           const ObjCInterfaceDecl *Class,
124                           bool isCategoryImpl,
125                           llvm::Value *Self,
126                           bool IsClassMessage,
127                           const CallArgList &CallArgs) = 0;
128
129  /// Emit the code to return the named protocol as an object, as in a
130  /// @protocol expression.
131  virtual llvm::Value *GenerateProtocolRef(CGBuilderTy &Builder,
132                                           const ObjCProtocolDecl *OPD) = 0;
133
134  /// Generate the named protocol.  Protocols contain method metadata but no
135  /// implementations.
136  virtual void GenerateProtocol(const ObjCProtocolDecl *OPD) = 0;
137
138  /// Generate a function preamble for a method with the specified
139  /// types.
140
141  // FIXME: Current this just generates the Function definition, but
142  // really this should also be generating the loads of the
143  // parameters, as the runtime should have full control over how
144  // parameters are passed.
145  virtual llvm::Function *GenerateMethod(const ObjCMethodDecl *OMD,
146                                         const ObjCContainerDecl *CD) = 0;
147
148  /// Return the runtime function for getting properties.
149  virtual llvm::Constant *GetPropertyGetFunction() = 0;
150
151  /// Return the runtime function for setting properties.
152  virtual llvm::Constant *GetPropertySetFunction() = 0;
153
154  /// GetClass - Return a reference to the class for the given
155  /// interface decl.
156  virtual llvm::Value *GetClass(CGBuilderTy &Builder,
157                                const ObjCInterfaceDecl *OID) = 0;
158
159  /// EnumerationMutationFunction - Return the function that's called by the
160  /// compiler when a mutation is detected during foreach iteration.
161  virtual llvm::Constant *EnumerationMutationFunction() = 0;
162
163  virtual void EmitTryOrSynchronizedStmt(CodeGen::CodeGenFunction &CGF,
164                                         const Stmt &S) = 0;
165  virtual void EmitThrowStmt(CodeGen::CodeGenFunction &CGF,
166                             const ObjCAtThrowStmt &S) = 0;
167  virtual llvm::Value *EmitObjCWeakRead(CodeGen::CodeGenFunction &CGF,
168                                        llvm::Value *AddrWeakObj) = 0;
169  virtual void EmitObjCWeakAssign(CodeGen::CodeGenFunction &CGF,
170                                  llvm::Value *src, llvm::Value *dest) = 0;
171  virtual void EmitObjCGlobalAssign(CodeGen::CodeGenFunction &CGF,
172                                    llvm::Value *src, llvm::Value *dest) = 0;
173  virtual void EmitObjCIvarAssign(CodeGen::CodeGenFunction &CGF,
174                                  llvm::Value *src, llvm::Value *dest) = 0;
175  virtual void EmitObjCStrongCastAssign(CodeGen::CodeGenFunction &CGF,
176                                        llvm::Value *src, llvm::Value *dest) = 0;
177
178  virtual LValue EmitObjCValueForIvar(CodeGen::CodeGenFunction &CGF,
179                                      QualType ObjectTy,
180                                      llvm::Value *BaseValue,
181                                      const ObjCIvarDecl *Ivar,
182                                      unsigned CVRQualifiers) = 0;
183  virtual llvm::Value *EmitIvarOffset(CodeGen::CodeGenFunction &CGF,
184                                      const ObjCInterfaceDecl *Interface,
185                                      const ObjCIvarDecl *Ivar) = 0;
186};
187
188/// Creates an instance of an Objective-C runtime class.
189//TODO: This should include some way of selecting which runtime to target.
190CGObjCRuntime *CreateGNUObjCRuntime(CodeGenModule &CGM);
191CGObjCRuntime *CreateMacObjCRuntime(CodeGenModule &CGM);
192CGObjCRuntime *CreateMacNonFragileABIObjCRuntime(CodeGenModule &CGM);
193}
194}
195#endif
196