JIT.h revision 8f613f30a78aa9d93d08a209b6c159c2000d8d6c 
1//===-- JIT.h - Class definition for the JIT --------------------*- 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 file defines the top-level JIT data structure.
11//
12//===----------------------------------------------------------------------===//
13
14#ifndef JIT_H
15#define JIT_H
16
17#include "llvm/ExecutionEngine/ExecutionEngine.h"
18#include "llvm/PassManager.h"
19
20namespace llvm {
21
22class Function;
23class GlobalValue;
24class Constant;
25class TargetMachine;
26class TargetJITInfo;
27class MachineCodeEmitter;
28
29class JITState {
30private:
31  FunctionPassManager PM;  // Passes to compile a function
32
33  /// PendingGlobals - Global variables which have had memory allocated for them
34  /// while a function was code generated, but which have not been initialized
35  /// yet.
36  std::vector<const GlobalVariable*> PendingGlobals;
37
38public:
39  explicit JITState(ModuleProvider *MP) : PM(MP) {}
40
41  FunctionPassManager &getPM(const MutexGuard &L) {
42    return PM;
43  }
44
45  std::vector<const GlobalVariable*> &getPendingGlobals(const MutexGuard &L) {
46    return PendingGlobals;
47  }
48};
49
50
51class JIT : public ExecutionEngine {
52  TargetMachine &TM;       // The current target we are compiling to
53  TargetJITInfo &TJI;      // The JITInfo for the target we are compiling to
54  MachineCodeEmitter *MCE; // MCE object
55
56  JITState *jitstate;
57
58  JIT(ModuleProvider *MP, TargetMachine &tm, TargetJITInfo &tji,
59      JITMemoryManager *JMM);
60public:
61  ~JIT();
62
63  static void Register() {
64    JITCtor = create;
65  }
66
67  /// getJITInfo - Return the target JIT information structure.
68  ///
69  TargetJITInfo &getJITInfo() const { return TJI; }
70
71  /// create - Create an return a new JIT compiler if there is one available
72  /// for the current target.  Otherwise, return null.
73  ///
74  static ExecutionEngine *create(ModuleProvider *MP, std::string *Err) {
75    return createJIT(MP, Err, 0);
76  }
77
78  virtual void addModuleProvider(ModuleProvider *MP);
79  virtual Module *removeModuleProvider(ModuleProvider *MP,
80                                       std::string *ErrInfo = 0);
81
82  /// runFunction - Start execution with the specified function and arguments.
83  ///
84  virtual GenericValue runFunction(Function *F,
85                                   const std::vector<GenericValue> &ArgValues);
86
87  /// getPointerToNamedFunction - This method returns the address of the
88  /// specified function by using the dlsym function call.  As such it is only
89  /// useful for resolving library symbols, not code generated symbols.
90  ///
91  void *getPointerToNamedFunction(const std::string &Name);
92
93  // CompilationCallback - Invoked the first time that a call site is found,
94  // which causes lazy compilation of the target function.
95  //
96  static void CompilationCallback();
97
98  /// getPointerToFunction - This returns the address of the specified function,
99  /// compiling it if necessary.
100  ///
101  void *getPointerToFunction(Function *F);
102
103  /// getOrEmitGlobalVariable - Return the address of the specified global
104  /// variable, possibly emitting it to memory if needed.  This is used by the
105  /// Emitter.
106  void *getOrEmitGlobalVariable(const GlobalVariable *GV);
107
108  /// getPointerToFunctionOrStub - If the specified function has been
109  /// code-gen'd, return a pointer to the function.  If not, compile it, or use
110  /// a stub to implement lazy compilation if available.
111  ///
112  void *getPointerToFunctionOrStub(Function *F);
113
114  /// recompileAndRelinkFunction - This method is used to force a function
115  /// which has already been compiled, to be compiled again, possibly
116  /// after it has been modified. Then the entry to the old copy is overwritten
117  /// with a branch to the new copy. If there was no old copy, this acts
118  /// just like JIT::getPointerToFunction().
119  ///
120  void *recompileAndRelinkFunction(Function *F);
121
122  /// freeMachineCodeForFunction - deallocate memory used to code-generate this
123  /// Function.
124  ///
125  void freeMachineCodeForFunction(Function *F);
126
127  /// getCodeEmitter - Return the code emitter this JIT is emitting into.
128  MachineCodeEmitter *getCodeEmitter() const { return MCE; }
129
130  static ExecutionEngine *createJIT(ModuleProvider *MP, std::string *Err,
131                                    JITMemoryManager *JMM);
132
133private:
134  static MachineCodeEmitter *createEmitter(JIT &J, JITMemoryManager *JMM);
135  void runJITOnFunction (Function *F);
136};
137
138} // End llvm namespace
139
140#endif
141