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/Support/InstVisitor.h"
21 #include "llvm/Support/CallSite.h"
22 #include "llvm/Target/TargetData.h"
23 #include "Support/DataTypes.h"
27 struct FunctionInfo; // Defined in ExecutionAnnotations.h
28 class gep_type_iterator;
31 // AllocaHolder - Object to track all of the blocks of memory allocated by
32 // alloca. When the function returns, this object is popped off the execution
33 // stack, which causes the dtor to be run, which frees all the alloca'd memory.
36 friend class AllocaHolderHandle;
37 std::vector<void*> Allocations;
40 AllocaHolder() : RefCnt(0) {}
41 void add(void *mem) { Allocations.push_back(mem); }
43 for (unsigned i = 0; i < Allocations.size(); ++i)
48 // AllocaHolderHandle gives AllocaHolder value semantics so we can stick it into
51 class AllocaHolderHandle {
54 AllocaHolderHandle() : H(new AllocaHolder()) { H->RefCnt++; }
55 AllocaHolderHandle(const AllocaHolderHandle &AH) : H(AH.H) { H->RefCnt++; }
56 ~AllocaHolderHandle() { if (--H->RefCnt == 0) delete H; }
58 void add(void *mem) { H->add(mem); }
61 typedef std::vector<GenericValue> ValuePlaneTy;
63 // ExecutionContext struct - This struct represents one stack frame currently
66 struct ExecutionContext {
67 Function *CurFunction;// The currently executing function
68 BasicBlock *CurBB; // The currently executing BB
69 BasicBlock::iterator CurInst; // The next instruction to execute
70 std::map<Value *, GenericValue> Values; // LLVM values used in this invocation
71 std::vector<GenericValue> VarArgs; // Values passed through an ellipsis
72 CallSite Caller; // Holds the call that called subframes.
73 // NULL if main func or debugger invoked fn
74 AllocaHolderHandle Allocas; // Track memory allocated by alloca
77 // Interpreter - This class represents the entirety of the interpreter.
79 class Interpreter : public ExecutionEngine, public InstVisitor<Interpreter> {
80 int ExitCode; // The exit code to be returned by the lli util
82 IntrinsicLowering *IL;
84 // The runtime stack of executing code. The top of the stack is the current
86 std::vector<ExecutionContext> ECStack;
88 // AtExitHandlers - List of functions to call when the program exits,
89 // registered with the atexit() library function.
90 std::vector<Function*> AtExitHandlers;
93 Interpreter(Module *M, bool isLittleEndian, bool isLongPointer,
94 IntrinsicLowering *IL);
97 /// runAtExitHandlers - Run any functions registered by the program's calls to
98 /// atexit(3), which we intercept and store in AtExitHandlers.
100 void runAtExitHandlers();
102 /// create - Create an interpreter ExecutionEngine. This can never fail. The
103 /// specified IntrinsicLowering implementation will be deleted when the
104 /// Interpreter execution engine is destroyed.
106 static ExecutionEngine *create(Module *M, IntrinsicLowering *IL);
108 /// run - Start execution with the specified function and arguments.
110 virtual GenericValue runFunction(Function *F,
111 const std::vector<GenericValue> &ArgValues);
113 /// recompileAndRelinkFunction - For the interpreter, functions are always
116 virtual void *recompileAndRelinkFunction(Function *F) {
117 return getPointerToFunction(F);
120 // Methods used to execute code:
121 // Place a call on the stack
122 void callFunction(Function *F, const std::vector<GenericValue> &ArgVals);
123 void run(); // Execute instructions until nothing left to do
125 // Opcode Implementations
126 void visitReturnInst(ReturnInst &I);
127 void visitBranchInst(BranchInst &I);
128 void visitSwitchInst(SwitchInst &I);
130 void visitBinaryOperator(BinaryOperator &I);
131 void visitAllocationInst(AllocationInst &I);
132 void visitFreeInst(FreeInst &I);
133 void visitLoadInst(LoadInst &I);
134 void visitStoreInst(StoreInst &I);
135 void visitGetElementPtrInst(GetElementPtrInst &I);
136 void visitPHINode(PHINode &PN) { assert(0 && "PHI nodes already handled!"); }
137 void visitCastInst(CastInst &I);
139 void visitCallSite(CallSite CS);
140 void visitCallInst(CallInst &I) { visitCallSite (CallSite (&I)); }
141 void visitInvokeInst(InvokeInst &I) { visitCallSite (CallSite (&I)); }
142 void visitUnwindInst(UnwindInst &I);
144 void visitShl(ShiftInst &I);
145 void visitShr(ShiftInst &I);
146 void visitVANextInst(VANextInst &I);
147 void visitVAArgInst(VAArgInst &I);
148 void visitInstruction(Instruction &I) {
150 assert(0 && "Instruction not interpretable yet!");
153 GenericValue callExternalFunction(Function *F,
154 const std::vector<GenericValue> &ArgVals);
155 void exitCalled(GenericValue GV);
157 void addAtExitHandler(Function *F) {
158 AtExitHandlers.push_back(F);
161 GenericValue *getFirstVarArg () {
162 return &(ECStack[ECStack.size () - 2].VarArgs[0]);
167 GenericValue executeGEPOperation(Value *Ptr, gep_type_iterator I,
168 gep_type_iterator E, ExecutionContext &SF);
170 private: // Helper functions
171 // SwitchToNewBasicBlock - Start execution in a new basic block and run any
172 // PHI nodes in the top of the block. This is used for intraprocedural
175 void SwitchToNewBasicBlock(BasicBlock *Dest, ExecutionContext &SF);
177 void *getPointerToFunction(Function *F) { return (void*)F; }
179 void initializeExecutionEngine();
180 void initializeExternalFunctions();
181 GenericValue getConstantExprValue(ConstantExpr *CE, ExecutionContext &SF);
182 GenericValue getOperandValue(Value *V, ExecutionContext &SF);
183 GenericValue executeCastOperation(Value *SrcVal, const Type *Ty,
184 ExecutionContext &SF);
185 void popStackAndReturnValueToCaller(const Type *RetTy, GenericValue Result);
188 } // End llvm namespace