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  JITMemoryManager *JMM;
62  std::vector<JITEventListener*> EventListeners;
63
64  /// AllocateGVsWithCode - Some applications require that global variables and
65  /// code be allocated into the same region of memory, in which case this flag
66  /// should be set to true.  Doing so breaks freeMachineCodeForFunction.
67  bool AllocateGVsWithCode;
68
69  /// True while the JIT is generating code.  Used to assert against recursive
70  /// entry.
71  bool isAlreadyCodeGenerating;
72
73  JITState *jitstate;
74
75  /// BasicBlockAddressMap - A mapping between LLVM basic blocks and their
76  /// actualized version, only filled for basic blocks that have their address
77  /// taken.
78  BasicBlockAddressMapTy BasicBlockAddressMap;
79
80
81  JIT(Module *M, TargetMachine &tm, TargetJITInfo &tji,
82      JITMemoryManager *JMM, bool AllocateGVsWithCode);
83public:
84  ~JIT();
85
86  static void Register() {
87    JITCtor = createJIT;
88  }
89
90  /// getJITInfo - Return the target JIT information structure.
91  ///
92  TargetJITInfo &getJITInfo() const { return TJI; }
93
94  /// create - Create an return a new JIT compiler if there is one available
95  /// for the current target.  Otherwise, return null.
96  ///
97  static ExecutionEngine *create(Module *M,
98                                 std::string *Err,
99                                 JITMemoryManager *JMM,
100                                 CodeGenOpt::Level OptLevel =
101                                   CodeGenOpt::Default,
102                                 bool GVsWithCode = true,
103                                 Reloc::Model RM = Reloc::Default,
104                                 CodeModel::Model CMM = CodeModel::JITDefault) {
105    return ExecutionEngine::createJIT(M, Err, JMM, OptLevel, GVsWithCode,
106                                      RM, CMM);
107  }
108
109  virtual void addModule(Module *M);
110
111  /// removeModule - Remove a Module from the list of modules.  Returns true if
112  /// M is found.
113  virtual bool removeModule(Module *M);
114
115  /// runFunction - Start execution with the specified function and arguments.
116  ///
117  virtual GenericValue runFunction(Function *F,
118                                   const std::vector<GenericValue> &ArgValues);
119
120  /// getPointerToNamedFunction - This method returns the address of the
121  /// specified function by using the MemoryManager. As such it is only
122  /// useful for resolving library symbols, not code generated symbols.
123  ///
124  /// If AbortOnFailure is false and no function with the given name is
125  /// found, this function silently returns a null pointer. Otherwise,
126  /// it prints a message to stderr and aborts.
127  ///
128  virtual void *getPointerToNamedFunction(const std::string &Name,
129                                          bool AbortOnFailure = true);
130
131  // CompilationCallback - Invoked the first time that a call site is found,
132  // which causes lazy compilation of the target function.
133  //
134  static void CompilationCallback();
135
136  /// getPointerToFunction - This returns the address of the specified function,
137  /// compiling it if necessary.
138  ///
139  void *getPointerToFunction(Function *F);
140
141  /// addPointerToBasicBlock - Adds address of the specific basic block.
142  void addPointerToBasicBlock(const BasicBlock *BB, void *Addr);
143
144  /// clearPointerToBasicBlock - Removes address of specific basic block.
145  void clearPointerToBasicBlock(const BasicBlock *BB);
146
147  /// getPointerToBasicBlock - This returns the address of the specified basic
148  /// block, assuming function is compiled.
149  void *getPointerToBasicBlock(BasicBlock *BB);
150
151  /// getOrEmitGlobalVariable - Return the address of the specified global
152  /// variable, possibly emitting it to memory if needed.  This is used by the
153  /// Emitter.
154  void *getOrEmitGlobalVariable(const GlobalVariable *GV);
155
156  /// getPointerToFunctionOrStub - If the specified function has been
157  /// code-gen'd, return a pointer to the function.  If not, compile it, or use
158  /// a stub to implement lazy compilation if available.
159  ///
160  void *getPointerToFunctionOrStub(Function *F);
161
162  /// recompileAndRelinkFunction - This method is used to force a function
163  /// which has already been compiled, to be compiled again, possibly
164  /// after it has been modified. Then the entry to the old copy is overwritten
165  /// with a branch to the new copy. If there was no old copy, this acts
166  /// just like JIT::getPointerToFunction().
167  ///
168  void *recompileAndRelinkFunction(Function *F);
169
170  /// freeMachineCodeForFunction - deallocate memory used to code-generate this
171  /// Function.
172  ///
173  void freeMachineCodeForFunction(Function *F);
174
175  /// addPendingFunction - while jitting non-lazily, a called but non-codegen'd
176  /// function was encountered.  Add it to a pending list to be processed after
177  /// the current function.
178  ///
179  void addPendingFunction(Function *F);
180
181  /// getCodeEmitter - Return the code emitter this JIT is emitting into.
182  ///
183  JITCodeEmitter *getCodeEmitter() const { return JCE; }
184
185  static ExecutionEngine *createJIT(Module *M,
186                                    std::string *ErrorStr,
187                                    JITMemoryManager *JMM,
188                                    bool GVsWithCode,
189                                    TargetMachine *TM);
190
191  // Run the JIT on F and return information about the generated code
192  void runJITOnFunction(Function *F, MachineCodeInfo *MCI = 0);
193
194  virtual void RegisterJITEventListener(JITEventListener *L);
195  virtual void UnregisterJITEventListener(JITEventListener *L);
196  /// These functions correspond to the methods on JITEventListener.  They
197  /// iterate over the registered listeners and call the corresponding method on
198  /// each.
199  void NotifyFunctionEmitted(
200      const Function &F, void *Code, size_t Size,
201      const JITEvent_EmittedFunctionDetails &Details);
202  void NotifyFreeingMachineCode(void *OldPtr);
203
204  BasicBlockAddressMapTy &
205  getBasicBlockAddressMap(const MutexGuard &) {
206    return BasicBlockAddressMap;
207  }
208
209
210private:
211  static JITCodeEmitter *createEmitter(JIT &J, JITMemoryManager *JMM,
212                                       TargetMachine &tm);
213  void runJITOnFunctionUnlocked(Function *F, const MutexGuard &locked);
214  void updateFunctionStub(Function *F);
215  void jitTheFunction(Function *F, const MutexGuard &locked);
216
217protected:
218
219  /// getMemoryforGV - Allocate memory for a global variable.
220  virtual char* getMemoryForGV(const GlobalVariable* GV);
221
222};
223
224} // End llvm namespace
225
226#endif
227