CGObjCRuntime.h revision 33fdb738a6c125f4c788733897021b7c1a062b0c 
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 Type;
29  class Value;
30  class Module;
31  class Function;
32}
33
34namespace clang {
35namespace CodeGen {
36  class CodeGenFunction;
37}
38
39  class ObjCAtTryStmt;
40  class ObjCAtThrowStmt;
41  class ObjCAtSynchronizedStmt;
42  class ObjCContainerDecl;
43  class ObjCCategoryImplDecl;
44  class ObjCImplementationDecl;
45  class ObjCInterfaceDecl;
46  class ObjCMessageExpr;
47  class ObjCMethodDecl;
48  class ObjCProtocolDecl;
49  class Selector;
50  class ObjCIvarDecl;
51  class ObjCStringLiteral;
52
53namespace CodeGen {
54  class CodeGenModule;
55
56//FIXME Several methods should be pure virtual but aren't to avoid the
57//partially-implemented subclass breaking.
58
59/// Implements runtime-specific code generation functions.
60class CGObjCRuntime {
61
62public:
63  virtual ~CGObjCRuntime();
64
65  /// Generate the function required to register all Objective-C components in
66  /// this compilation unit with the runtime library.
67  virtual llvm::Function *ModuleInitFunction() = 0;
68
69  /// Get a selector for the specified name and type values. The
70  /// return value should have the LLVM type for pointer-to
71  /// ASTContext::getObjCSelType().
72  virtual llvm::Value *GetSelector(CGBuilderTy &Builder,
73                                   Selector Sel) = 0;
74
75  /// Generate a constant string object.
76  virtual llvm::Constant *GenerateConstantString(const ObjCStringLiteral *) = 0;
77
78  /// Generate a category.  A category contains a list of methods (and
79  /// accompanying metadata) and a list of protocols.
80  virtual void GenerateCategory(const ObjCCategoryImplDecl *OCD) = 0;
81
82  /// Generate a class stucture for this class.
83  virtual void GenerateClass(const ObjCImplementationDecl *OID) = 0;
84
85  /// Generate an Objective-C message send operation.
86  virtual CodeGen::RValue
87  GenerateMessageSend(CodeGen::CodeGenFunction &CGF,
88                      QualType ResultType,
89                      Selector Sel,
90                      llvm::Value *Receiver,
91                      bool IsClassMessage,
92                      const CallArgList &CallArgs) = 0;
93
94  /// Generate an Objective-C message send operation to the super
95  /// class initiated in a method for Class and with the given Self
96  /// object.
97  virtual CodeGen::RValue
98  GenerateMessageSendSuper(CodeGen::CodeGenFunction &CGF,
99                           QualType ResultType,
100                           Selector Sel,
101                           const ObjCInterfaceDecl *Class,
102                           bool isCategoryImpl,
103                           llvm::Value *Self,
104                           bool IsClassMessage,
105                           const CallArgList &CallArgs) = 0;
106
107  /// Emit the code to return the named protocol as an object, as in a
108  /// @protocol expression.
109  virtual llvm::Value *GenerateProtocolRef(CGBuilderTy &Builder,
110                                           const ObjCProtocolDecl *OPD) = 0;
111
112  /// Generate the named protocol.  Protocols contain method metadata but no
113  /// implementations.
114  virtual void GenerateProtocol(const ObjCProtocolDecl *OPD) = 0;
115
116  /// Generate a function preamble for a method with the specified
117  /// types.
118
119  // FIXME: Current this just generates the Function definition, but
120  // really this should also be generating the loads of the
121  // parameters, as the runtime should have full control over how
122  // parameters are passed.
123  virtual llvm::Function *GenerateMethod(const ObjCMethodDecl *OMD,
124                                         const ObjCContainerDecl *CD) = 0;
125
126  /// Return the runtime function for getting properties.
127  virtual llvm::Constant *GetPropertyGetFunction() = 0;
128
129  /// Return the runtime function for setting properties.
130  virtual llvm::Constant *GetPropertySetFunction() = 0;
131
132  /// GetClass - Return a reference to the class for the given
133  /// interface decl.
134  virtual llvm::Value *GetClass(CGBuilderTy &Builder,
135                                const ObjCInterfaceDecl *OID) = 0;
136
137  /// EnumerationMutationFunction - Return the function that's called by the
138  /// compiler when a mutation is detected during foreach iteration.
139  virtual llvm::Constant *EnumerationMutationFunction() = 0;
140
141  /// If instance variable addresses are determined at runtime then this should
142  /// return true, otherwise instance variables will be accessed directly from
143  /// the structure.  If this returns true then @defs is invalid for this
144  /// runtime and a warning should be generated.
145  virtual bool LateBoundIVars() const { return false; }
146
147  virtual void EmitTryOrSynchronizedStmt(CodeGen::CodeGenFunction &CGF,
148                                         const Stmt &S) = 0;
149  virtual void EmitThrowStmt(CodeGen::CodeGenFunction &CGF,
150                             const ObjCAtThrowStmt &S) = 0;
151  virtual llvm::Value * EmitObjCWeakRead(CodeGen::CodeGenFunction &CGF,
152                                         llvm::Value *AddrWeakObj) = 0;
153  virtual void EmitObjCWeakAssign(CodeGen::CodeGenFunction &CGF,
154                                  llvm::Value *src, llvm::Value *dest) = 0;
155  virtual void EmitObjCGlobalAssign(CodeGen::CodeGenFunction &CGF,
156                                    llvm::Value *src, llvm::Value *dest) = 0;
157  virtual void EmitObjCIvarAssign(CodeGen::CodeGenFunction &CGF,
158                                  llvm::Value *src, llvm::Value *dest) = 0;
159  virtual void EmitObjCStrongCastAssign(CodeGen::CodeGenFunction &CGF,
160                                        llvm::Value *src, llvm::Value *dest) = 0;
161
162  virtual LValue EmitObjCValueForIvar(CodeGen::CodeGenFunction &CGF,
163                                      QualType ObjectTy,
164                                      llvm::Value *BaseValue,
165                                      const ObjCIvarDecl *Ivar,
166                                      const FieldDecl *Field,
167                                      unsigned CVRQualifiers) = 0;
168  virtual llvm::Value *EmitIvarOffset(CodeGen::CodeGenFunction &CGF,
169                                      ObjCInterfaceDecl *Interface,
170                                      const ObjCIvarDecl *Ivar) = 0;
171};
172
173/// Creates an instance of an Objective-C runtime class.
174//TODO: This should include some way of selecting which runtime to target.
175CGObjCRuntime *CreateGNUObjCRuntime(CodeGenModule &CGM);
176CGObjCRuntime *CreateMacObjCRuntime(CodeGenModule &CGM);
177CGObjCRuntime *CreateMacNonFragileABIObjCRuntime(CodeGenModule &CGM);
178}
179}
180#endif
181