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//===-- Interpreter.h ------------------------------------------*- C++ -*--===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by the LLVM research group and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This header file defines the interpreter structure
//
//===----------------------------------------------------------------------===//
#ifndef LLI_INTERPRETER_H
#define LLI_INTERPRETER_H
#include "llvm/BasicBlock.h"
#include "llvm/Assembly/CachedWriter.h"
#include "llvm/ExecutionEngine/ExecutionEngine.h"
#include "llvm/ExecutionEngine/GenericValue.h"
#include "llvm/Support/InstVisitor.h"
#include "llvm/Target/TargetData.h"
#include "Support/DataTypes.h"
extern CachedWriter CW; // Object to accelerate printing of LLVM
struct FunctionInfo; // Defined in ExecutionAnnotations.h
// AllocaHolder - Object to track all of the blocks of memory allocated by
// alloca. When the function returns, this object is poped off the execution
// stack, which causes the dtor to be run, which frees all the alloca'd memory.
//
class AllocaHolder {
friend class AllocaHolderHandle;
std::vector<void*> Allocations;
unsigned RefCnt;
public:
AllocaHolder() : RefCnt(0) {}
void add(void *mem) { Allocations.push_back(mem); }
~AllocaHolder() {
for (unsigned i = 0; i < Allocations.size(); ++i)
free(Allocations[i]);
}
};
// AllocaHolderHandle gives AllocaHolder value semantics so we can stick it into
// a vector...
//
class AllocaHolderHandle {
AllocaHolder *H;
public:
AllocaHolderHandle() : H(new AllocaHolder()) { H->RefCnt++; }
AllocaHolderHandle(const AllocaHolderHandle &AH) : H(AH.H) { H->RefCnt++; }
~AllocaHolderHandle() { if (--H->RefCnt == 0) delete H; }
void add(void *mem) { H->add(mem); }
};
typedef std::vector<GenericValue> ValuePlaneTy;
// ExecutionContext struct - This struct represents one stack frame currently
// executing.
//
struct ExecutionContext {
Function *CurFunction;// The currently executing function
BasicBlock *CurBB; // The currently executing BB
BasicBlock::iterator CurInst; // The next instruction to execute
FunctionInfo *FuncInfo; // The FuncInfo annotation for the function
std::vector<ValuePlaneTy> Values;// ValuePlanes for each type
std::vector<GenericValue> VarArgs; // Values passed through an ellipsis
CallInst *Caller; // Holds the call that called subframes.
// NULL if main func or debugger invoked fn
AllocaHolderHandle Allocas; // Track memory allocated by alloca
};
// Interpreter - This class represents the entirety of the interpreter.
//
class Interpreter : public ExecutionEngine, public InstVisitor<Interpreter> {
int ExitCode; // The exit code to be returned by the lli util
bool Trace; // Tracing enabled?
int CurFrame; // The current stack frame being inspected
TargetData TD;
// The runtime stack of executing code. The top of the stack is the current
// function record.
std::vector<ExecutionContext> ECStack;
// AtExitHandlers - List of functions to call when the program exits,
// registered with the atexit() library function.
std::vector<Function*> AtExitHandlers;
std::map<Function*, FunctionInfo*> FunctionInfoMap;
public:
Interpreter(Module *M, bool isLittleEndian, bool isLongPointer,
bool TraceMode);
inline ~Interpreter() { CW.setModule(0); }
/// runAtExitHandlers - Run any functions registered by the
/// program's calls to atexit(3), which we intercept and store in
/// AtExitHandlers.
///
void runAtExitHandlers ();
/// create - Create an interpreter ExecutionEngine. This can never fail.
///
static ExecutionEngine *create(Module *M, bool TraceMode);
/// run - Start execution with the specified function and arguments.
///
virtual GenericValue run(Function *F,
const std::vector<GenericValue> &ArgValues);
// Methods used for debug printouts:
static void print(const Type *Ty, GenericValue V);
static void printValue(const Type *Ty, GenericValue V);
// Methods used to execute code:
// Place a call on the stack
void callFunction(Function *F, const std::vector<GenericValue> &ArgVals);
void executeInstruction(); // Execute one instruction
void run(); // Execute instructions until nothing left to do
// Opcode Implementations
void visitReturnInst(ReturnInst &I);
void visitBranchInst(BranchInst &I);
void visitSwitchInst(SwitchInst &I);
void visitBinaryOperator(BinaryOperator &I);
void visitAllocationInst(AllocationInst &I);
void visitFreeInst(FreeInst &I);
void visitLoadInst(LoadInst &I);
void visitStoreInst(StoreInst &I);
void visitGetElementPtrInst(GetElementPtrInst &I);
void visitPHINode(PHINode &PN) { assert(0 && "PHI nodes already handled!"); }
void visitCastInst(CastInst &I);
void visitCallInst(CallInst &I);
void visitShl(ShiftInst &I);
void visitShr(ShiftInst &I);
void visitVANextInst(VANextInst &I);
void visitInstruction(Instruction &I) {
std::cerr << I;
assert(0 && "Instruction not interpretable yet!");
}
GenericValue callExternalFunction(Function *F,
const std::vector<GenericValue> &ArgVals);
void exitCalled(GenericValue GV);
void addAtExitHandler(Function *F) {
AtExitHandlers.push_back(F);
}
//FIXME: private:
public:
GenericValue executeGEPOperation(Value *Ptr, User::op_iterator I,
User::op_iterator E, ExecutionContext &SF);
private: // Helper functions
// SwitchToNewBasicBlock - Start execution in a new basic block and run any
// PHI nodes in the top of the block. This is used for intraprocedural
// control flow.
//
void SwitchToNewBasicBlock(BasicBlock *Dest, ExecutionContext &SF);
void *getPointerToFunction(Function *F) { return (void*)F; }
void initializeExecutionEngine();
void initializeExternalFunctions();
GenericValue getOperandValue(Value *V, ExecutionContext &SF);
GenericValue executeCastOperation(Value *SrcVal, const Type *Ty,
ExecutionContext &SF);
};
#endif
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