1 //===- ExecutionEngine.h - Abstract Execution Engine Interface --*- 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 abstract interface that implements execution support
13 //===----------------------------------------------------------------------===//
15 #ifndef EXECUTION_ENGINE_H
16 #define EXECUTION_ENGINE_H
34 class IntrinsicLowering;
36 class ExecutionEngine {
40 /// GlobalAddressMap - A mapping between LLVM global values and their
41 /// actualized version...
42 std::map<const GlobalValue*, void *> GlobalAddressMap;
44 /// GlobalAddressReverseMap - This is the reverse mapping of GlobalAddressMap,
45 /// used to convert raw addresses into the LLVM global value that is emitted
46 /// at the address. This map is not computed unless getGlobalValueAtAddress
47 /// is called at some point.
48 std::map<void *, const GlobalValue*> GlobalAddressReverseMap;
52 void setTargetData(const TargetData &td) {
57 ExecutionEngine(ModuleProvider *P);
58 ExecutionEngine(Module *M);
59 virtual ~ExecutionEngine();
61 Module &getModule() const { return CurMod; }
62 const TargetData &getTargetData() const { return *TD; }
64 /// create - This is the factory method for creating an execution engine which
65 /// is appropriate for the current machine. If specified, the
66 /// IntrinsicLowering implementation should be allocated on the heap.
67 static ExecutionEngine *create(ModuleProvider *MP, bool ForceInterpreter,
68 IntrinsicLowering *IL = 0);
70 /// runFunction - Execute the specified function with the specified arguments,
71 /// and return the result.
73 virtual GenericValue runFunction(Function *F,
74 const std::vector<GenericValue> &ArgValues) = 0;
76 /// runFunctionAsMain - This is a helper function which wraps runFunction to
77 /// handle the common task of starting up main with the specified argc, argv,
78 /// and envp parameters.
79 int runFunctionAsMain(Function *Fn, const std::vector<std::string> &argv,
80 const char * const * envp);
83 void addGlobalMapping(const GlobalValue *GV, void *Addr) {
84 void *&CurVal = GlobalAddressMap[GV];
85 assert((CurVal == 0 || Addr == 0) && "GlobalMapping already established!");
88 // If we are using the reverse mapping, add it too
89 if (!GlobalAddressReverseMap.empty()) {
90 const GlobalValue *&V = GlobalAddressReverseMap[Addr];
91 assert((V == 0 || GV == 0) && "GlobalMapping already established!");
96 /// getPointerToGlobalIfAvailable - This returns the address of the specified
97 /// global value if it is available, otherwise it returns null.
99 void *getPointerToGlobalIfAvailable(const GlobalValue *GV) {
100 std::map<const GlobalValue*, void*>::iterator I = GlobalAddressMap.find(GV);
101 return I != GlobalAddressMap.end() ? I->second : 0;
104 /// getPointerToGlobal - This returns the address of the specified global
105 /// value. This may involve code generation if it's a function.
107 void *getPointerToGlobal(const GlobalValue *GV);
109 /// getPointerToFunction - The different EE's represent function bodies in
110 /// different ways. They should each implement this to say what a function
111 /// pointer should look like.
113 virtual void *getPointerToFunction(Function *F) = 0;
115 /// getPointerToFunctionOrStub - If the specified function has been
116 /// code-gen'd, return a pointer to the function. If not, compile it, or use
117 /// a stub to implement lazy compilation if available.
119 virtual void *getPointerToFunctionOrStub(Function *F) {
120 // Default implementation, just codegen the function.
121 return getPointerToFunction(F);
124 /// getGlobalValueAtAddress - Return the LLVM global value object that starts
125 /// at the specified address.
127 const GlobalValue *getGlobalValueAtAddress(void *Addr);
130 void StoreValueToMemory(GenericValue Val, GenericValue *Ptr, const Type *Ty);
131 void InitializeMemory(const Constant *Init, void *Addr);
133 /// recompileAndRelinkFunction - This method is used to force a function
134 /// which has already been compiled to be compiled again, possibly
135 /// after it has been modified. Then the entry to the old copy is overwritten
136 /// with a branch to the new copy. If there was no old copy, this acts
137 /// just like VM::getPointerToFunction().
139 virtual void *recompileAndRelinkFunction(Function *F) = 0;
141 /// getOrEmitGlobalVariable - Return the address of the specified global
142 /// variable, possibly emitting it to memory if needed. This is used by the
144 virtual void *getOrEmitGlobalVariable(const GlobalVariable *GV) {
145 return getPointerToGlobal((GlobalValue*)GV);
151 // EmitGlobalVariable - This method emits the specified global variable to the
152 // address specified in GlobalAddresses, or allocates new memory if it's not
153 // already in the map.
154 void EmitGlobalVariable(const GlobalVariable *GV);
156 GenericValue getConstantValue(const Constant *C);
157 GenericValue LoadValueFromMemory(GenericValue *Ptr, const Type *Ty);
160 } // End llvm namespace