1 //===-- Interpreter.h ------------------------------------------*- C++ -*--===//
3 // This header file defines the interpreter structure
5 //===----------------------------------------------------------------------===//
7 #ifndef LLI_INTERPRETER_H
8 #define LLI_INTERPRETER_H
10 #include "../ExecutionEngine.h"
11 #include "../GenericValue.h"
12 #include "Support/DataTypes.h"
13 #include "llvm/Assembly/CachedWriter.h"
14 #include "llvm/Target/TargetData.h"
15 #include "llvm/BasicBlock.h"
16 #include "llvm/Support/InstVisitor.h"
18 extern CachedWriter CW; // Object to accelerate printing of LLVM
20 struct FunctionInfo; // Defined in ExecutionAnnotations.h
22 // AllocaHolder - Object to track all of the blocks of memory allocated by
23 // alloca. When the function returns, this object is poped off the execution
24 // stack, which causes the dtor to be run, which frees all the alloca'd memory.
27 friend class AllocaHolderHandle;
28 std::vector<void*> Allocations;
31 AllocaHolder() : RefCnt(0) {}
32 void add(void *mem) { Allocations.push_back(mem); }
34 for (unsigned i = 0; i < Allocations.size(); ++i)
39 // AllocaHolderHandle gives AllocaHolder value semantics so we can stick it into
42 class AllocaHolderHandle {
45 AllocaHolderHandle() : H(new AllocaHolder()) { H->RefCnt++; }
46 AllocaHolderHandle(const AllocaHolderHandle &AH) : H(AH.H) { H->RefCnt++; }
47 ~AllocaHolderHandle() { if (--H->RefCnt == 0) delete H; }
49 void add(void *mem) { H->add(mem); }
52 typedef std::vector<GenericValue> ValuePlaneTy;
54 // ExecutionContext struct - This struct represents one stack frame currently
57 struct ExecutionContext {
58 Function *CurFunction;// The currently executing function
59 BasicBlock *CurBB; // The currently executing BB
60 BasicBlock::iterator CurInst; // The next instruction to execute
61 FunctionInfo *FuncInfo; // The FuncInfo annotation for the function
62 std::vector<ValuePlaneTy> Values;// ValuePlanes for each type
63 std::vector<GenericValue> VarArgs; // Values passed through an ellipsis
65 CallInst *Caller; // Holds the call that called subframes.
66 // NULL if main func or debugger invoked fn
67 AllocaHolderHandle Allocas; // Track memory allocated by alloca
70 // Interpreter - This class represents the entirety of the interpreter.
72 class Interpreter : public ExecutionEngine, public InstVisitor<Interpreter> {
73 int ExitCode; // The exit code to be returned by the lli util
74 bool Trace; // Tracing enabled?
75 int CurFrame; // The current stack frame being inspected
78 // The runtime stack of executing code. The top of the stack is the current
80 std::vector<ExecutionContext> ECStack;
82 // AtExitHandlers - List of functions to call when the program exits,
83 // registered with the atexit() library function.
84 std::vector<Function*> AtExitHandlers;
86 Interpreter(Module *M, bool isLittleEndian, bool isLongPointer,
88 inline ~Interpreter() { CW.setModule(0); }
90 /// runAtExitHandlers - Run any functions registered by the
91 /// program's calls to atexit(3), which we intercept and store in
94 void runAtExitHandlers ();
96 /// create - Create an interpreter ExecutionEngine. This can never fail.
98 static ExecutionEngine *create(Module *M, bool TraceMode);
100 /// run - Start execution with the specified function and arguments.
102 virtual GenericValue run(Function *F,
103 const std::vector<GenericValue> &ArgValues);
105 // Methods used for debug printouts:
106 static void print(const Type *Ty, GenericValue V);
107 static void printValue(const Type *Ty, GenericValue V);
109 // Methods used to execute code:
110 // Place a call on the stack
111 void callFunction(Function *F, const std::vector<GenericValue> &ArgVals);
112 void executeInstruction(); // Execute one instruction
113 void run(); // Execute instructions until nothing left to do
115 // Opcode Implementations
116 void visitReturnInst(ReturnInst &I);
117 void visitBranchInst(BranchInst &I);
118 void visitSwitchInst(SwitchInst &I);
120 void visitBinaryOperator(BinaryOperator &I);
121 void visitAllocationInst(AllocationInst &I);
122 void visitFreeInst(FreeInst &I);
123 void visitLoadInst(LoadInst &I);
124 void visitStoreInst(StoreInst &I);
125 void visitGetElementPtrInst(GetElementPtrInst &I);
127 void visitPHINode(PHINode &PN) { assert(0 && "PHI nodes already handled!"); }
128 void visitCastInst(CastInst &I);
129 void visitCallInst(CallInst &I);
130 void visitShl(ShiftInst &I);
131 void visitShr(ShiftInst &I);
132 void visitVarArgInst(VarArgInst &I);
133 void visitInstruction(Instruction &I) {
135 assert(0 && "Instruction not interpretable yet!");
138 GenericValue callExternalFunction(Function *F,
139 const std::vector<GenericValue> &ArgVals);
140 void exitCalled(GenericValue GV);
142 void addAtExitHandler(Function *F) {
143 AtExitHandlers.push_back(F);
148 GenericValue executeGEPOperation(Value *Ptr, User::op_iterator I,
149 User::op_iterator E, ExecutionContext &SF);
151 private: // Helper functions
152 // SwitchToNewBasicBlock - Start execution in a new basic block and run any
153 // PHI nodes in the top of the block. This is used for intraprocedural
156 void SwitchToNewBasicBlock(BasicBlock *Dest, ExecutionContext &SF);
158 void *getPointerToFunction(Function *F) { return (void*)F; }
160 void initializeExecutionEngine();
161 void initializeExternalFunctions();
162 GenericValue getOperandValue(Value *V, ExecutionContext &SF);
163 GenericValue executeCastOperation(Value *SrcVal, const Type *Ty,
164 ExecutionContext &SF);