JIT.h revision 98a366d547772010e94609e4584489b3e5ce0043 
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 TargetMachine;
24class TargetJITInfo;
25class MachineCodeEmitter;
26
27class JITState {
28private:
29  FunctionPassManager PM;  // Passes to compile a function
30  ModuleProvider *MP;      // ModuleProvider used to create the PM
31
32  /// PendingFunctions - Functions which have not been code generated yet, but
33  /// were called from a function being code generated.
34  std::vector<Function*> PendingFunctions;
35
36public:
37  explicit JITState(ModuleProvider *MP) : PM(MP), MP(MP) {}
38
39  FunctionPassManager &getPM(const MutexGuard &L) {
40    return PM;
41  }
42
43  ModuleProvider *getMP() const { return MP; }
44  std::vector<Function*> &getPendingFunctions(const MutexGuard &L) {
45    return PendingFunctions;
46  }
47};
48
49
50class JIT : public ExecutionEngine {
51  TargetMachine &TM;       // The current target we are compiling to
52  TargetJITInfo &TJI;      // The JITInfo for the target we are compiling to
53  MachineCodeEmitter *MCE; // MCE object
54
55  JITState *jitstate;
56
57  JIT(ModuleProvider *MP, TargetMachine &tm, TargetJITInfo &tji,
58      JITMemoryManager *JMM, CodeGenOpt::Level OptLevel);
59public:
60  ~JIT();
61
62  static void Register() {
63    JITCtor = create;
64  }
65
66  /// getJITInfo - Return the target JIT information structure.
67  ///
68  TargetJITInfo &getJITInfo() const { return TJI; }
69
70  /// create - Create an return a new JIT compiler if there is one available
71  /// for the current target.  Otherwise, return null.
72  ///
73  static ExecutionEngine *create(ModuleProvider *MP, std::string *Err,
74                                 CodeGenOpt::Level OptLevel =
75                                   CodeGenOpt::Default) {
76    return createJIT(MP, Err, 0, OptLevel);
77  }
78
79  virtual void addModuleProvider(ModuleProvider *MP);
80
81  /// removeModuleProvider - Remove a ModuleProvider from the list of modules.
82  /// Relases the Module from the ModuleProvider, materializing it in the
83  /// process, and returns the materialized Module.
84  virtual Module *removeModuleProvider(ModuleProvider *MP,
85                                       std::string *ErrInfo = 0);
86
87  /// deleteModuleProvider - Remove a ModuleProvider from the list of modules,
88  /// and deletes the ModuleProvider and owned Module.  Avoids materializing
89  /// the underlying module.
90  virtual void deleteModuleProvider(ModuleProvider *P,std::string *ErrInfo = 0);
91
92  /// runFunction - Start execution with the specified function and arguments.
93  ///
94  virtual GenericValue runFunction(Function *F,
95                                   const std::vector<GenericValue> &ArgValues);
96
97  /// getPointerToNamedFunction - This method returns the address of the
98  /// specified function by using the dlsym function call.  As such it is only
99  /// useful for resolving library symbols, not code generated symbols.
100  ///
101  /// If AbortOnFailure is false and no function with the given name is
102  /// found, this function silently returns a null pointer. Otherwise,
103  /// it prints a message to stderr and aborts.
104  ///
105  void *getPointerToNamedFunction(const std::string &Name,
106                                  bool AbortOnFailure = true);
107
108  // CompilationCallback - Invoked the first time that a call site is found,
109  // which causes lazy compilation of the target function.
110  //
111  static void CompilationCallback();
112
113  /// getPointerToFunction - This returns the address of the specified function,
114  /// compiling it if necessary.
115  ///
116  void *getPointerToFunction(Function *F);
117
118  /// getOrEmitGlobalVariable - Return the address of the specified global
119  /// variable, possibly emitting it to memory if needed.  This is used by the
120  /// Emitter.
121  void *getOrEmitGlobalVariable(const GlobalVariable *GV);
122
123  /// getPointerToFunctionOrStub - If the specified function has been
124  /// code-gen'd, return a pointer to the function.  If not, compile it, or use
125  /// a stub to implement lazy compilation if available.
126  ///
127  void *getPointerToFunctionOrStub(Function *F);
128
129  /// recompileAndRelinkFunction - This method is used to force a function
130  /// which has already been compiled, to be compiled again, possibly
131  /// after it has been modified. Then the entry to the old copy is overwritten
132  /// with a branch to the new copy. If there was no old copy, this acts
133  /// just like JIT::getPointerToFunction().
134  ///
135  void *recompileAndRelinkFunction(Function *F);
136
137  /// freeMachineCodeForFunction - deallocate memory used to code-generate this
138  /// Function.
139  ///
140  void freeMachineCodeForFunction(Function *F);
141
142  /// addPendingFunction - while jitting non-lazily, a called but non-codegen'd
143  /// function was encountered.  Add it to a pending list to be processed after
144  /// the current function.
145  ///
146  void addPendingFunction(Function *F);
147
148  /// getCodeEmitter - Return the code emitter this JIT is emitting into.
149  MachineCodeEmitter *getCodeEmitter() const { return MCE; }
150
151  static ExecutionEngine *createJIT(ModuleProvider *MP, std::string *Err,
152                                    JITMemoryManager *JMM,
153                                    CodeGenOpt::Level OptLevel);
154
155private:
156  static MachineCodeEmitter *createEmitter(JIT &J, JITMemoryManager *JMM);
157  void runJITOnFunction(Function *F);
158  void runJITOnFunctionUnlocked(Function *F, const MutexGuard &locked);
159  void updateFunctionStub(Function *F);
160  void updateDlsymStubTable();
161
162protected:
163
164  /// getMemoryforGV - Allocate memory for a global variable.
165  virtual char* getMemoryForGV(const GlobalVariable* GV);
166
167};
168
169} // End llvm namespace
170
171#endif
172