1 //===-- Interpreter.h ------------------------------------------*- 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 header file defines the interpreter structure
12 //===----------------------------------------------------------------------===//
14 #ifndef LLI_INTERPRETER_H
15 #define LLI_INTERPRETER_H
17 #include "llvm/Function.h"
18 #include "llvm/ExecutionEngine/ExecutionEngine.h"
19 #include "llvm/ExecutionEngine/GenericValue.h"
20 #include "llvm/ADT/APInt.h"
21 #include "llvm/Support/InstVisitor.h"
22 #include "llvm/Support/CallSite.h"
23 #include "llvm/Target/TargetData.h"
24 #include "llvm/Support/DataTypes.h"
28 class IntrinsicLowering;
30 template<typename T> class generic_gep_type_iterator;
32 typedef generic_gep_type_iterator<User::const_op_iterator> gep_type_iterator;
35 // AllocaHolder - Object to track all of the blocks of memory allocated by
36 // alloca. When the function returns, this object is popped off the execution
37 // stack, which causes the dtor to be run, which frees all the alloca'd memory.
40 friend class AllocaHolderHandle;
41 std::vector<void*> Allocations;
44 AllocaHolder() : RefCnt(0) {}
45 void add(void *mem) { Allocations.push_back(mem); }
47 for (unsigned i = 0; i < Allocations.size(); ++i)
52 // AllocaHolderHandle gives AllocaHolder value semantics so we can stick it into
55 class AllocaHolderHandle {
58 AllocaHolderHandle() : H(new AllocaHolder()) { H->RefCnt++; }
59 AllocaHolderHandle(const AllocaHolderHandle &AH) : H(AH.H) { H->RefCnt++; }
60 ~AllocaHolderHandle() { if (--H->RefCnt == 0) delete H; }
62 void add(void *mem) { H->add(mem); }
65 typedef std::vector<GenericValue> ValuePlaneTy;
67 // ExecutionContext struct - This struct represents one stack frame currently
70 struct ExecutionContext {
71 Function *CurFunction;// The currently executing function
72 BasicBlock *CurBB; // The currently executing BB
73 BasicBlock::iterator CurInst; // The next instruction to execute
74 std::map<Value *, GenericValue> Values; // LLVM values used in this invocation
75 std::vector<GenericValue> VarArgs; // Values passed through an ellipsis
76 CallSite Caller; // Holds the call that called subframes.
77 // NULL if main func or debugger invoked fn
78 AllocaHolderHandle Allocas; // Track memory allocated by alloca
79 std::vector<APInt*> APInts; // Track memory allocated for APInts
80 APInt* getAPInt(uint32_t BitWidth) {
81 APInt* Result = new APInt(BitWidth, 0);
82 APInts.push_back(Result);
86 while (!APInts.empty()) {
93 // Interpreter - This class represents the entirety of the interpreter.
95 class Interpreter : public ExecutionEngine, public InstVisitor<Interpreter> {
96 GenericValue ExitValue; // The return value of the called function
98 IntrinsicLowering *IL;
100 // The runtime stack of executing code. The top of the stack is the current
102 std::vector<ExecutionContext> ECStack;
104 // AtExitHandlers - List of functions to call when the program exits,
105 // registered with the atexit() library function.
106 std::vector<Function*> AtExitHandlers;
109 Interpreter(Module *M);
112 /// runAtExitHandlers - Run any functions registered by the program's calls to
113 /// atexit(3), which we intercept and store in AtExitHandlers.
115 void runAtExitHandlers();
117 static void Register() {
121 /// create - Create an interpreter ExecutionEngine. This can never fail.
123 static ExecutionEngine *create(ModuleProvider *M);
125 /// run - Start execution with the specified function and arguments.
127 virtual GenericValue runFunction(Function *F,
128 const std::vector<GenericValue> &ArgValues);
130 /// recompileAndRelinkFunction - For the interpreter, functions are always
133 virtual void *recompileAndRelinkFunction(Function *F) {
134 return getPointerToFunction(F);
137 /// freeMachineCodeForFunction - The interpreter does not generate any code.
139 void freeMachineCodeForFunction(Function *F) { }
141 // Methods used to execute code:
142 // Place a call on the stack
143 void callFunction(Function *F, const std::vector<GenericValue> &ArgVals);
144 void run(); // Execute instructions until nothing left to do
146 // Opcode Implementations
147 void visitReturnInst(ReturnInst &I);
148 void visitBranchInst(BranchInst &I);
149 void visitSwitchInst(SwitchInst &I);
151 void visitBinaryOperator(BinaryOperator &I);
152 void visitICmpInst(ICmpInst &I);
153 void visitFCmpInst(FCmpInst &I);
154 void visitAllocationInst(AllocationInst &I);
155 void visitFreeInst(FreeInst &I);
156 void visitLoadInst(LoadInst &I);
157 void visitStoreInst(StoreInst &I);
158 void visitGetElementPtrInst(GetElementPtrInst &I);
159 void visitPHINode(PHINode &PN) { assert(0 && "PHI nodes already handled!"); }
160 void visitTruncInst(TruncInst &I);
161 void visitZExtInst(ZExtInst &I);
162 void visitSExtInst(SExtInst &I);
163 void visitFPTruncInst(FPTruncInst &I);
164 void visitFPExtInst(FPExtInst &I);
165 void visitUIToFPInst(UIToFPInst &I);
166 void visitSIToFPInst(SIToFPInst &I);
167 void visitFPToUIInst(FPToUIInst &I);
168 void visitFPToSIInst(FPToSIInst &I);
169 void visitPtrToIntInst(PtrToIntInst &I);
170 void visitIntToPtrInst(IntToPtrInst &I);
171 void visitBitCastInst(BitCastInst &I);
172 void visitSelectInst(SelectInst &I);
175 void visitCallSite(CallSite CS);
176 void visitCallInst(CallInst &I) { visitCallSite (CallSite (&I)); }
177 void visitInvokeInst(InvokeInst &I) { visitCallSite (CallSite (&I)); }
178 void visitUnwindInst(UnwindInst &I);
179 void visitUnreachableInst(UnreachableInst &I);
181 void visitShl(BinaryOperator &I);
182 void visitLShr(BinaryOperator &I);
183 void visitAShr(BinaryOperator &I);
185 void visitVAArgInst(VAArgInst &I);
186 void visitInstruction(Instruction &I) {
188 assert(0 && "Instruction not interpretable yet!");
191 GenericValue callExternalFunction(Function *F,
192 const std::vector<GenericValue> &ArgVals);
193 void exitCalled(GenericValue GV);
195 void addAtExitHandler(Function *F) {
196 AtExitHandlers.push_back(F);
199 GenericValue *getFirstVarArg () {
200 return &(ECStack.back ().VarArgs[0]);
205 GenericValue executeGEPOperation(Value *Ptr, gep_type_iterator I,
206 gep_type_iterator E, ExecutionContext &SF);
208 private: // Helper functions
209 // SwitchToNewBasicBlock - Start execution in a new basic block and run any
210 // PHI nodes in the top of the block. This is used for intraprocedural
213 void SwitchToNewBasicBlock(BasicBlock *Dest, ExecutionContext &SF);
215 void *getPointerToFunction(Function *F) { return (void*)F; }
217 void initializeExecutionEngine();
218 void initializeExternalFunctions();
219 GenericValue getConstantExprValue(ConstantExpr *CE, ExecutionContext &SF);
220 GenericValue getOperandValue(Value *V, ExecutionContext &SF);
221 GenericValue executeTruncInst(Value *SrcVal, const Type *DstTy,
222 ExecutionContext &SF);
223 GenericValue executeSExtInst(Value *SrcVal, const Type *DstTy,
224 ExecutionContext &SF);
225 GenericValue executeZExtInst(Value *SrcVal, const Type *DstTy,
226 ExecutionContext &SF);
227 GenericValue executeFPTruncInst(Value *SrcVal, const Type *DstTy,
228 ExecutionContext &SF);
229 GenericValue executeFPExtInst(Value *SrcVal, const Type *DstTy,
230 ExecutionContext &SF);
231 GenericValue executeFPToUIInst(Value *SrcVal, const Type *DstTy,
232 ExecutionContext &SF);
233 GenericValue executeFPToSIInst(Value *SrcVal, const Type *DstTy,
234 ExecutionContext &SF);
235 GenericValue executeUIToFPInst(Value *SrcVal, const Type *DstTy,
236 ExecutionContext &SF);
237 GenericValue executeSIToFPInst(Value *SrcVal, const Type *DstTy,
238 ExecutionContext &SF);
239 GenericValue executePtrToIntInst(Value *SrcVal, const Type *DstTy,
240 ExecutionContext &SF);
241 GenericValue executeIntToPtrInst(Value *SrcVal, const Type *DstTy,
242 ExecutionContext &SF);
243 GenericValue executeBitCastInst(Value *SrcVal, const Type *DstTy,
244 ExecutionContext &SF);
245 GenericValue executeCastOperation(Instruction::CastOps opcode, Value *SrcVal,
246 const Type *Ty, ExecutionContext &SF);
247 void popStackAndReturnValueToCaller(const Type *RetTy, GenericValue Result);
251 } // End llvm namespace