1 //===-- JIT.h - Class definition for the JIT --------------------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file was developed by the LLVM research group and is distributed under
6 // the University of Illinois Open Source License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file defines the top-level JIT data structure.
12 //===----------------------------------------------------------------------===//
17 #include "llvm/ExecutionEngine/ExecutionEngine.h"
18 #include "llvm/PassManager.h"
28 class MachineCodeEmitter;
30 class JIT : public ExecutionEngine {
31 TargetMachine &TM; // The current target we are compiling to
32 TargetJITInfo &TJI; // The JITInfo for the target we are compiling to
34 FunctionPassManager PM; // Passes to compile a function
35 MachineCodeEmitter *MCE; // MCE object
37 /// PendingGlobals - Global variables which have had memory allocated for them
38 /// while a function was code generated, but which have not been initialized
40 std::vector<const GlobalVariable*> PendingGlobals;
42 JIT(ModuleProvider *MP, TargetMachine &tm, TargetJITInfo &tji);
46 /// create - Create an return a new JIT compiler if there is one available
47 /// for the current target. Otherwise, return null.
49 static ExecutionEngine *create(ModuleProvider *MP);
51 /// run - Start execution with the specified function and arguments.
53 virtual GenericValue run(Function *F,
54 const std::vector<GenericValue> &ArgValues);
56 /// getPointerToNamedFunction - This method returns the address of the
57 /// specified function by using the dlsym function call. As such it is only
58 /// useful for resolving library symbols, not code generated symbols.
60 void *getPointerToNamedFunction(const std::string &Name);
62 // CompilationCallback - Invoked the first time that a call site is found,
63 // which causes lazy compilation of the target function.
65 static void CompilationCallback();
67 /// runAtExitHandlers - Before exiting the program, at_exit functions must be
68 /// called. This method calls them.
70 static void runAtExitHandlers();
72 /// getPointerToFunction - This returns the address of the specified function,
73 /// compiling it if necessary.
75 void *getPointerToFunction(Function *F);
77 /// getOrEmitGlobalVariable - Return the address of the specified global
78 /// variable, possibly emitting it to memory if needed. This is used by the
80 void *getOrEmitGlobalVariable(const GlobalVariable *GV);
82 /// getPointerToFunctionOrStub - If the specified function has been
83 /// code-gen'd, return a pointer to the function. If not, compile it, or use
84 /// a stub to implement lazy compilation if available.
86 void *getPointerToFunctionOrStub(Function *F);
88 /// recompileAndRelinkFunction - This method is used to force a function
89 /// which has already been compiled, to be compiled again, possibly
90 /// after it has been modified. Then the entry to the old copy is overwritten
91 /// with a branch to the new copy. If there was no old copy, this acts
92 /// just like JIT::getPointerToFunction().
94 void *recompileAndRelinkFunction(Function *F);
97 static MachineCodeEmitter *createEmitter(JIT &J);
98 void runJITOnFunction (Function *F);
101 } // End llvm namespace