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;
30 // AllocaHolder - Object to track all of the blocks of memory allocated by
31 // alloca. When the function returns, this object is poped off the execution
32 // stack, which causes the dtor to be run, which frees all the alloca'd memory.
35 friend class AllocaHolderHandle;
36 std::vector<void*> Allocations;
39 AllocaHolder() : RefCnt(0) {}
40 void add(void *mem) { Allocations.push_back(mem); }
42 for (unsigned i = 0; i < Allocations.size(); ++i)
47 // AllocaHolderHandle gives AllocaHolder value semantics so we can stick it into
50 class AllocaHolderHandle {
53 AllocaHolderHandle() : H(new AllocaHolder()) { H->RefCnt++; }
54 AllocaHolderHandle(const AllocaHolderHandle &AH) : H(AH.H) { H->RefCnt++; }
55 ~AllocaHolderHandle() { if (--H->RefCnt == 0) delete H; }
57 void add(void *mem) { H->add(mem); }
60 typedef std::vector<GenericValue> ValuePlaneTy;
62 // ExecutionContext struct - This struct represents one stack frame currently
65 struct ExecutionContext {
66 Function *CurFunction;// The currently executing function
67 BasicBlock *CurBB; // The currently executing BB
68 BasicBlock::iterator CurInst; // The next instruction to execute
69 std::map<Value *, GenericValue> Values; // LLVM values used in this invocation
70 std::vector<GenericValue> VarArgs; // Values passed through an ellipsis
71 CallSite Caller; // Holds the call that called subframes.
72 // NULL if main func or debugger invoked fn
73 AllocaHolderHandle Allocas; // Track memory allocated by alloca
76 // Interpreter - This class represents the entirety of the interpreter.
78 class Interpreter : public ExecutionEngine, public InstVisitor<Interpreter> {
79 int ExitCode; // The exit code to be returned by the lli util
82 // The runtime stack of executing code. The top of the stack is the current
84 std::vector<ExecutionContext> ECStack;
86 // AtExitHandlers - List of functions to call when the program exits,
87 // registered with the atexit() library function.
88 std::vector<Function*> AtExitHandlers;
91 Interpreter(Module *M, bool isLittleEndian, bool isLongPointer);
92 inline ~Interpreter() { }
94 /// runAtExitHandlers - Run any functions registered by the
95 /// program's calls to atexit(3), which we intercept and store in
98 void runAtExitHandlers ();
100 /// create - Create an interpreter ExecutionEngine. This can never fail.
102 static ExecutionEngine *create(Module *M);
104 /// run - Start execution with the specified function and arguments.
106 virtual GenericValue run(Function *F,
107 const std::vector<GenericValue> &ArgValues);
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 run(); // Execute instructions until nothing left to do
114 // Opcode Implementations
115 void visitReturnInst(ReturnInst &I);
116 void visitBranchInst(BranchInst &I);
117 void visitSwitchInst(SwitchInst &I);
119 void visitBinaryOperator(BinaryOperator &I);
120 void visitAllocationInst(AllocationInst &I);
121 void visitFreeInst(FreeInst &I);
122 void visitLoadInst(LoadInst &I);
123 void visitStoreInst(StoreInst &I);
124 void visitGetElementPtrInst(GetElementPtrInst &I);
125 void visitPHINode(PHINode &PN) { assert(0 && "PHI nodes already handled!"); }
126 void visitCastInst(CastInst &I);
128 void visitCallSite(CallSite CS);
129 void visitCallInst(CallInst &I) { visitCallSite (CallSite (&I)); }
130 void visitInvokeInst(InvokeInst &I) { visitCallSite (CallSite (&I)); }
131 void visitUnwindInst(UnwindInst &I);
133 void visitShl(ShiftInst &I);
134 void visitShr(ShiftInst &I);
135 void visitVANextInst(VANextInst &I);
136 void visitVAArgInst(VAArgInst &I);
137 void visitInstruction(Instruction &I) {
139 assert(0 && "Instruction not interpretable yet!");
142 GenericValue callExternalFunction(Function *F,
143 const std::vector<GenericValue> &ArgVals);
144 void exitCalled(GenericValue GV);
146 void addAtExitHandler(Function *F) {
147 AtExitHandlers.push_back(F);
150 GenericValue *getFirstVarArg () {
151 return &(ECStack[ECStack.size () - 2].VarArgs[0]);
156 GenericValue executeGEPOperation(Value *Ptr, gep_type_iterator I,
157 gep_type_iterator E, ExecutionContext &SF);
159 private: // Helper functions
160 // SwitchToNewBasicBlock - Start execution in a new basic block and run any
161 // PHI nodes in the top of the block. This is used for intraprocedural
164 void SwitchToNewBasicBlock(BasicBlock *Dest, ExecutionContext &SF);
166 void *getPointerToFunction(Function *F) { return (void*)F; }
168 void initializeExecutionEngine();
169 void initializeExternalFunctions();
170 GenericValue getOperandValue(Value *V, ExecutionContext &SF);
171 GenericValue executeCastOperation(Value *SrcVal, const Type *Ty,
172 ExecutionContext &SF);
173 void popStackAndReturnValueToCaller(const Type *RetTy, GenericValue Result);
176 } // End llvm namespace