JIT.h revision 3e29671cca14f8fce1ea6b602175880cb3df7199 
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#include "llvm/Support/ValueHandle.h"
20
21namespace llvm {
22
23class Function;
24struct JITEvent_EmittedFunctionDetails;
25class MachineCodeEmitter;
26class MachineCodeInfo;
27class TargetJITInfo;
28class TargetMachine;
29
30class JITState {
31private:
32  FunctionPassManager PM;  // Passes to compile a function
33  Module *M;               // Module used to create the PM
34
35  /// PendingFunctions - Functions which have not been code generated yet, but
36  /// were called from a function being code generated.
37  std::vector<AssertingVH<Function> > PendingFunctions;
38
39public:
40  explicit JITState(Module *M) : PM(M), M(M) {}
41
42  FunctionPassManager &getPM(const MutexGuard &L) {
43    return PM;
44  }
45
46  Module *getModule() const { return M; }
47  std::vector<AssertingVH<Function> > &getPendingFunctions(const MutexGuard &L){
48    return PendingFunctions;
49  }
50};
51
52
53class JIT : public ExecutionEngine {
54  /// types
55  typedef ValueMap<const BasicBlock *, void *>
56      BasicBlockAddressMapTy;
57  /// data
58  TargetMachine &TM;       // The current target we are compiling to
59  TargetJITInfo &TJI;      // The JITInfo for the target we are compiling to
60  JITCodeEmitter *JCE;     // JCE object
61  std::vector<JITEventListener*> EventListeners;
62
63  /// AllocateGVsWithCode - Some applications require that global variables and
64  /// code be allocated into the same region of memory, in which case this flag
65  /// should be set to true.  Doing so breaks freeMachineCodeForFunction.
66  bool AllocateGVsWithCode;
67
68  /// True while the JIT is generating code.  Used to assert against recursive
69  /// entry.
70  bool isAlreadyCodeGenerating;
71
72  JITState *jitstate;
73
74  /// BasicBlockAddressMap - A mapping between LLVM basic blocks and their
75  /// actualized version, only filled for basic blocks that have their address
76  /// taken.
77  BasicBlockAddressMapTy BasicBlockAddressMap;
78
79
80  JIT(Module *M, TargetMachine &tm, TargetJITInfo &tji,
81      JITMemoryManager *JMM, bool AllocateGVsWithCode);
82public:
83  ~JIT();
84
85  static void Register() {
86    JITCtor = createJIT;
87  }
88
89  /// getJITInfo - Return the target JIT information structure.
90  ///
91  TargetJITInfo &getJITInfo() const { return TJI; }
92
93  /// create - Create an return a new JIT compiler if there is one available
94  /// for the current target.  Otherwise, return null.
95  ///
96  static ExecutionEngine *create(Module *M,
97                                 std::string *Err,
98                                 JITMemoryManager *JMM,
99                                 CodeGenOpt::Level OptLevel =
100                                   CodeGenOpt::Default,
101                                 bool GVsWithCode = true,
102                                 Reloc::Model RM = Reloc::Default,
103                                 CodeModel::Model CMM = CodeModel::JITDefault) {
104    return ExecutionEngine::createJIT(M, Err, JMM, OptLevel, GVsWithCode,
105                                      RM, CMM);
106  }
107
108  virtual void addModule(Module *M);
109
110  /// removeModule - Remove a Module from the list of modules.  Returns true if
111  /// M is found.
112  virtual bool removeModule(Module *M);
113
114  /// runFunction - Start execution with the specified function and arguments.
115  ///
116  virtual GenericValue runFunction(Function *F,
117                                   const std::vector<GenericValue> &ArgValues);
118
119  /// getPointerToNamedFunction - This method returns the address of the
120  /// specified function by using the dlsym function call.  As such it is only
121  /// useful for resolving library symbols, not code generated symbols.
122  ///
123  /// If AbortOnFailure is false and no function with the given name is
124  /// found, this function silently returns a null pointer. Otherwise,
125  /// it prints a message to stderr and aborts.
126  ///
127  virtual void *getPointerToNamedFunction(const std::string &Name,
128                                          bool AbortOnFailure = true);
129
130  // CompilationCallback - Invoked the first time that a call site is found,
131  // which causes lazy compilation of the target function.
132  //
133  static void CompilationCallback();
134
135  /// getPointerToFunction - This returns the address of the specified function,
136  /// compiling it if necessary.
137  ///
138  void *getPointerToFunction(Function *F);
139
140  /// addPointerToBasicBlock - Adds address of the specific basic block.
141  void addPointerToBasicBlock(const BasicBlock *BB, void *Addr);
142
143  /// clearPointerToBasicBlock - Removes address of specific basic block.
144  void clearPointerToBasicBlock(const BasicBlock *BB);
145
146  /// getPointerToBasicBlock - This returns the address of the specified basic
147  /// block, assuming function is compiled.
148  void *getPointerToBasicBlock(BasicBlock *BB);
149
150  /// getOrEmitGlobalVariable - Return the address of the specified global
151  /// variable, possibly emitting it to memory if needed.  This is used by the
152  /// Emitter.
153  void *getOrEmitGlobalVariable(const GlobalVariable *GV);
154
155  /// getPointerToFunctionOrStub - If the specified function has been
156  /// code-gen'd, return a pointer to the function.  If not, compile it, or use
157  /// a stub to implement lazy compilation if available.
158  ///
159  void *getPointerToFunctionOrStub(Function *F);
160
161  /// recompileAndRelinkFunction - This method is used to force a function
162  /// which has already been compiled, to be compiled again, possibly
163  /// after it has been modified. Then the entry to the old copy is overwritten
164  /// with a branch to the new copy. If there was no old copy, this acts
165  /// just like JIT::getPointerToFunction().
166  ///
167  void *recompileAndRelinkFunction(Function *F);
168
169  /// freeMachineCodeForFunction - deallocate memory used to code-generate this
170  /// Function.
171  ///
172  void freeMachineCodeForFunction(Function *F);
173
174  /// addPendingFunction - while jitting non-lazily, a called but non-codegen'd
175  /// function was encountered.  Add it to a pending list to be processed after
176  /// the current function.
177  ///
178  void addPendingFunction(Function *F);
179
180  /// getCodeEmitter - Return the code emitter this JIT is emitting into.
181  ///
182  JITCodeEmitter *getCodeEmitter() const { return JCE; }
183
184  static ExecutionEngine *createJIT(Module *M,
185                                    std::string *ErrorStr,
186                                    JITMemoryManager *JMM,
187                                    bool GVsWithCode,
188                                    TargetMachine *TM);
189
190  // Run the JIT on F and return information about the generated code
191  void runJITOnFunction(Function *F, MachineCodeInfo *MCI = 0);
192
193  virtual void RegisterJITEventListener(JITEventListener *L);
194  virtual void UnregisterJITEventListener(JITEventListener *L);
195  /// These functions correspond to the methods on JITEventListener.  They
196  /// iterate over the registered listeners and call the corresponding method on
197  /// each.
198  void NotifyFunctionEmitted(
199      const Function &F, void *Code, size_t Size,
200      const JITEvent_EmittedFunctionDetails &Details);
201  void NotifyFreeingMachineCode(void *OldPtr);
202
203  BasicBlockAddressMapTy &
204  getBasicBlockAddressMap(const MutexGuard &) {
205    return BasicBlockAddressMap;
206  }
207
208
209private:
210  static JITCodeEmitter *createEmitter(JIT &J, JITMemoryManager *JMM,
211                                       TargetMachine &tm);
212  void runJITOnFunctionUnlocked(Function *F, const MutexGuard &locked);
213  void updateFunctionStub(Function *F);
214  void jitTheFunction(Function *F, const MutexGuard &locked);
215
216protected:
217
218  /// getMemoryforGV - Allocate memory for a global variable.
219  virtual char* getMemoryForGV(const GlobalVariable* GV);
220
221};
222
223} // End llvm namespace
224
225#endif
226